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from sympy import (Add, Abs, Catalan, cos, Derivative, E, EulerGamma, exp, factorial, factorial2, Function, GoldenRatio, TribonacciConstant, I, Integer, Integral, Interval, Lambda, Limit, Matrix, nan, O, oo, pi, Pow, Rational, Float, Rel, S, sin, SparseMatrix, sqrt, summation, Sum, Symbol, symbols, Wild, WildFunction, zeta, zoo, Dummy, Dict, Tuple, FiniteSet, factor, subfactorial, true, false, Equivalent, Xor, Complement, SymmetricDifference, AccumBounds, UnevaluatedExpr, Eq, Ne, Quaternion, Subs, MatrixSymbol, MatrixSlice, Q) from sympy.core import Expr, Mul from sympy.core.parameters import _exp_is_pow from sympy.external import import_module from sympy.physics.control.lti import TransferFunction, Series, Parallel, Feedback from sympy.physics.units import second, joule from sympy.polys import (Poly, rootof, RootSum, groebner, ring, field, ZZ, QQ, ZZ_I, QQ_I, lex, grlex) from sympy.geometry import Point, Circle, Polygon, Ellipse, Triangle from sympy.tensor import NDimArray from sympy.tensor.array.expressions.array_expressions import ArraySymbol, ArrayElement from sympy.testing.pytest import raises from sympy.printing import sstr, sstrrepr, StrPrinter from sympy.core.trace import Tr x, y, z, w, t = symbols('x,y,z,w,t') d = Dummy('d') def test_printmethod(): class R(Abs): def _sympystr(self, printer): return "foo(%s)" % printer._print(self.args[0]) assert sstr(R(x)) == "foo(x)" class R(Abs): def _sympystr(self, printer): return "foo" assert sstr(R(x)) == "foo" def test_Abs(): assert str(Abs(x)) == "Abs(x)" assert str(Abs(Rational(1, 6))) == "1/6" assert str(Abs(Rational(-1, 6))) == "1/6" def test_Add(): assert str(x + y) == "x + y" assert str(x + 1) == "x + 1" assert str(x + x**2) == "x**2 + x" assert str(Add(0, 1, evaluate=False)) == "0 + 1" assert str(Add(0, 0, 1, evaluate=False)) == "0 + 0 + 1" assert str(1.0*x) == "1.0*x" assert str(5 + x + y + x*y + x**2 + y**2) == "x**2 + x*y + x + y**2 + y + 5" assert str(1 + x + x**2/2 + x**3/3) == "x**3/3 + x**2/2 + x + 1" assert str(2*x - 7*x**2 + 2 + 3*y) == "-7*x**2 + 2*x + 3*y + 2" assert str(x - y) == "x - y" assert str(2 - x) == "2 - x" assert str(x - 2) == "x - 2" assert str(x - y - z - w) == "-w + x - y - z" assert str(x - z*y**2*z*w) == "-w*y**2*z**2 + x" assert str(x - 1*y*x*y) == "-x*y**2 + x" assert str(sin(x).series(x, 0, 15)) == "x - x**3/6 + x**5/120 - x**7/5040 + x**9/362880 - x**11/39916800 + x**13/6227020800 + O(x**15)" def test_Catalan(): assert str(Catalan) == "Catalan" def test_ComplexInfinity(): assert str(zoo) == "zoo" def test_Derivative(): assert str(Derivative(x, y)) == "Derivative(x, y)" assert str(Derivative(x**2, x, evaluate=False)) == "Derivative(x**2, x)" assert str(Derivative( x**2/y, x, y, evaluate=False)) == "Derivative(x**2/y, x, y)" def test_dict(): assert str({1: 1 + x}) == sstr({1: 1 + x}) == "{1: x + 1}" assert str({1: x**2, 2: y*x}) in ("{1: x**2, 2: x*y}", "{2: x*y, 1: x**2}") assert sstr({1: x**2, 2: y*x}) == "{1: x**2, 2: x*y}" def test_Dict(): assert str(Dict({1: 1 + x})) == sstr({1: 1 + x}) == "{1: x + 1}" assert str(Dict({1: x**2, 2: y*x})) in ( "{1: x**2, 2: x*y}", "{2: x*y, 1: x**2}") assert sstr(Dict({1: x**2, 2: y*x})) == "{1: x**2, 2: x*y}" def test_Dummy(): assert str(d) == "_d" assert str(d + x) == "_d + x" def test_EulerGamma(): assert str(EulerGamma) == "EulerGamma" def test_Exp(): assert str(E) == "E" with _exp_is_pow(True): assert str(exp(x)) == "E**x" def test_factorial(): n = Symbol('n', integer=True) assert str(factorial(-2)) == "zoo" assert str(factorial(0)) == "1" assert str(factorial(7)) == "5040" assert str(factorial(n)) == "factorial(n)" assert str(factorial(2*n)) == "factorial(2*n)" assert str(factorial(factorial(n))) == 'factorial(factorial(n))' assert str(factorial(factorial2(n))) == 'factorial(factorial2(n))' assert str(factorial2(factorial(n))) == 'factorial2(factorial(n))' assert str(factorial2(factorial2(n))) == 'factorial2(factorial2(n))' assert str(subfactorial(3)) == "2" assert str(subfactorial(n)) == "subfactorial(n)" assert str(subfactorial(2*n)) == "subfactorial(2*n)" def test_Function(): f = Function('f') fx = f(x) w = WildFunction('w') assert str(f) == "f" assert str(fx) == "f(x)" assert str(w) == "w_" def test_Geometry(): assert sstr(Point(0, 0)) == 'Point2D(0, 0)' assert sstr(Circle(Point(0, 0), 3)) == 'Circle(Point2D(0, 0), 3)' assert sstr(Ellipse(Point(1, 2), 3, 4)) == 'Ellipse(Point2D(1, 2), 3, 4)' assert sstr(Triangle(Point(1, 1), Point(7, 8), Point(0, -1))) == \ 'Triangle(Point2D(1, 1), Point2D(7, 8), Point2D(0, -1))' assert sstr(Polygon(Point(5, 6), Point(-2, -3), Point(0, 0), Point(4, 7))) == \ 'Polygon(Point2D(5, 6), Point2D(-2, -3), Point2D(0, 0), Point2D(4, 7))' assert sstr(Triangle(Point(0, 0), Point(1, 0), Point(0, 1)), sympy_integers=True) == \ 'Triangle(Point2D(S(0), S(0)), Point2D(S(1), S(0)), Point2D(S(0), S(1)))' assert sstr(Ellipse(Point(1, 2), 3, 4), sympy_integers=True) == \ 'Ellipse(Point2D(S(1), S(2)), S(3), S(4))' def test_GoldenRatio(): assert str(GoldenRatio) == "GoldenRatio" def test_TribonacciConstant(): assert str(TribonacciConstant) == "TribonacciConstant" def test_ImaginaryUnit(): assert str(I) == "I" def test_Infinity(): assert str(oo) == "oo" assert str(oo*I) == "oo*I" def test_Integer(): assert str(Integer(-1)) == "-1" assert str(Integer(1)) == "1" assert str(Integer(-3)) == "-3" assert str(Integer(0)) == "0" assert str(Integer(25)) == "25" def test_Integral(): assert str(Integral(sin(x), y)) == "Integral(sin(x), y)" assert str(Integral(sin(x), (y, 0, 1))) == "Integral(sin(x), (y, 0, 1))" def test_Interval(): n = (S.NegativeInfinity, 1, 2, S.Infinity) for i in range(len(n)): for j in range(i + 1, len(n)): for l in (True, False): for r in (True, False): ival = Interval(n[i], n[j], l, r) assert S(str(ival)) == ival def test_AccumBounds(): a = Symbol('a', real=True) assert str(AccumBounds(0, a)) == "AccumBounds(0, a)" assert str(AccumBounds(0, 1)) == "AccumBounds(0, 1)" def test_Lambda(): assert str(Lambda(d, d**2)) == "Lambda(_d, _d**2)" # issue 2908 assert str(Lambda((), 1)) == "Lambda((), 1)" assert str(Lambda((), x)) == "Lambda((), x)" assert str(Lambda((x, y), x+y)) == "Lambda((x, y), x + y)" assert str(Lambda(((x, y),), x+y)) == "Lambda(((x, y),), x + y)" def test_Limit(): assert str(Limit(sin(x)/x, x, y)) == "Limit(sin(x)/x, x, y)" assert str(Limit(1/x, x, 0)) == "Limit(1/x, x, 0)" assert str( Limit(sin(x)/x, x, y, dir="-")) == "Limit(sin(x)/x, x, y, dir='-')" def test_list(): assert str([x]) == sstr([x]) == "[x]" assert str([x**2, x*y + 1]) == sstr([x**2, x*y + 1]) == "[x**2, x*y + 1]" assert str([x**2, [y + x]]) == sstr([x**2, [y + x]]) == "[x**2, [x + y]]" def test_Matrix_str(): M = Matrix([[x**+1, 1], [y, x + y]]) assert str(M) == "Matrix([[x, 1], [y, x + y]])" assert sstr(M) == "Matrix([\n[x, 1],\n[y, x + y]])" M = Matrix([[1]]) assert str(M) == sstr(M) == "Matrix([[1]])" M = Matrix([[1, 2]]) assert str(M) == sstr(M) == "Matrix([[1, 2]])" M = Matrix() assert str(M) == sstr(M) == "Matrix(0, 0, [])" M = Matrix(0, 1, lambda i, j: 0) assert str(M) == sstr(M) == "Matrix(0, 1, [])" def test_Mul(): assert str(x/y) == "x/y" assert str(y/x) == "y/x" assert str(x/y/z) == "x/(y*z)" assert str((x + 1)/(y + 2)) == "(x + 1)/(y + 2)" assert str(2*x/3) == '2*x/3' assert str(-2*x/3) == '-2*x/3' assert str(-1.0*x) == '-1.0*x' assert str(1.0*x) == '1.0*x' assert str(Mul(0, 1, evaluate=False)) == '0*1' assert str(Mul(1, 0, evaluate=False)) == '1*0' assert str(Mul(1, 1, evaluate=False)) == '1*1' assert str(Mul(1, 1, 1, evaluate=False)) == '1*1*1' assert str(Mul(1, 2, evaluate=False)) == '1*2' assert str(Mul(1, S.Half, evaluate=False)) == '1*(1/2)' assert str(Mul(1, 1, S.Half, evaluate=False)) == '1*1*(1/2)' assert str(Mul(1, 1, 2, 3, x, evaluate=False)) == '1*1*2*3*x' assert str(Mul(1, -1, evaluate=False)) == '1*(-1)' assert str(Mul(-1, 1, evaluate=False)) == '-1*1' assert str(Mul(4, 3, 2, 1, 0, y, x, evaluate=False)) == '4*3*2*1*0*y*x' assert str(Mul(4, 3, 2, 1+z, 0, y, x, evaluate=False)) == '4*3*2*(z + 1)*0*y*x' assert str(Mul(Rational(2, 3), Rational(5, 7), evaluate=False)) == '(2/3)*(5/7)' # For issue 14160 assert str(Mul(-2, x, Pow(Mul(y,y,evaluate=False), -1, evaluate=False), evaluate=False)) == '-2*x/(y*y)' class CustomClass1(Expr): is_commutative = True class CustomClass2(Expr): is_commutative = True cc1 = CustomClass1() cc2 = CustomClass2() assert str(Rational(2)*cc1) == '2*CustomClass1()' assert str(cc1*Rational(2)) == '2*CustomClass1()' assert str(cc1*Float("1.5")) == '1.5*CustomClass1()' assert str(cc2*Rational(2)) == '2*CustomClass2()' assert str(cc2*Rational(2)*cc1) == '2*CustomClass1()*CustomClass2()' assert str(cc1*Rational(2)*cc2) == '2*CustomClass1()*CustomClass2()' def test_NaN(): assert str(nan) == "nan" def test_NegativeInfinity(): assert str(-oo) == "-oo" def test_Order(): assert str(O(x)) == "O(x)" assert str(O(x**2)) == "O(x**2)" assert str(O(x*y)) == "O(x*y, x, y)" assert str(O(x, x)) == "O(x)" assert str(O(x, (x, 0))) == "O(x)" assert str(O(x, (x, oo))) == "O(x, (x, oo))" assert str(O(x, x, y)) == "O(x, x, y)" assert str(O(x, x, y)) == "O(x, x, y)" assert str(O(x, (x, oo), (y, oo))) == "O(x, (x, oo), (y, oo))" def test_Permutation_Cycle(): from sympy.combinatorics import Permutation, Cycle # general principle: economically, canonically show all moved elements # and the size of the permutation. for p, s in [ (Cycle(), '()'), (Cycle(2), '(2)'), (Cycle(2, 1), '(1 2)'), (Cycle(1, 2)(5)(6, 7)(10), '(1 2)(6 7)(10)'), (Cycle(3, 4)(1, 2)(3, 4), '(1 2)(4)'), ]: assert sstr(p) == s for p, s in [ (Permutation([]), 'Permutation([])'), (Permutation([], size=1), 'Permutation([0])'), (Permutation([], size=2), 'Permutation([0, 1])'), (Permutation([], size=10), 'Permutation([], size=10)'), (Permutation([1, 0, 2]), 'Permutation([1, 0, 2])'), (Permutation([1, 0, 2, 3, 4, 5]), 'Permutation([1, 0], size=6)'), (Permutation([1, 0, 2, 3, 4, 5], size=10), 'Permutation([1, 0], size=10)'), ]: assert sstr(p, perm_cyclic=False) == s for p, s in [ (Permutation([]), '()'), (Permutation([], size=1), '(0)'), (Permutation([], size=2), '(1)'), (Permutation([], size=10), '(9)'), (Permutation([1, 0, 2]), '(2)(0 1)'), (Permutation([1, 0, 2, 3, 4, 5]), '(5)(0 1)'), (Permutation([1, 0, 2, 3, 4, 5], size=10), '(9)(0 1)'), (Permutation([0, 1, 3, 2, 4, 5], size=10), '(9)(2 3)'), ]: assert sstr(p) == s def test_Pi(): assert str(pi) == "pi" def test_Poly(): assert str(Poly(0, x)) == "Poly(0, x, domain='ZZ')" assert str(Poly(1, x)) == "Poly(1, x, domain='ZZ')" assert str(Poly(x, x)) == "Poly(x, x, domain='ZZ')" assert str(Poly(2*x + 1, x)) == "Poly(2*x + 1, x, domain='ZZ')" assert str(Poly(2*x - 1, x)) == "Poly(2*x - 1, x, domain='ZZ')" assert str(Poly(-1, x)) == "Poly(-1, x, domain='ZZ')" assert str(Poly(-x, x)) == "Poly(-x, x, domain='ZZ')" assert str(Poly(-2*x + 1, x)) == "Poly(-2*x + 1, x, domain='ZZ')" assert str(Poly(-2*x - 1, x)) == "Poly(-2*x - 1, x, domain='ZZ')" assert str(Poly(x - 1, x)) == "Poly(x - 1, x, domain='ZZ')" assert str(Poly(2*x + x**5, x)) == "Poly(x**5 + 2*x, x, domain='ZZ')" assert str(Poly(3**(2*x), 3**x)) == "Poly((3**x)**2, 3**x, domain='ZZ')" assert str(Poly((x**2)**x)) == "Poly(((x**2)**x), (x**2)**x, domain='ZZ')" assert str(Poly((x + y)**3, (x + y), expand=False) ) == "Poly((x + y)**3, x + y, domain='ZZ')" assert str(Poly((x - 1)**2, (x - 1), expand=False) ) == "Poly((x - 1)**2, x - 1, domain='ZZ')" assert str( Poly(x**2 + 1 + y, x)) == "Poly(x**2 + y + 1, x, domain='ZZ[y]')" assert str( Poly(x**2 - 1 + y, x)) == "Poly(x**2 + y - 1, x, domain='ZZ[y]')" assert str(Poly(x**2 + I*x, x)) == "Poly(x**2 + I*x, x, domain='ZZ_I')" assert str(Poly(x**2 - I*x, x)) == "Poly(x**2 - I*x, x, domain='ZZ_I')" assert str(Poly(-x*y*z + x*y - 1, x, y, z) ) == "Poly(-x*y*z + x*y - 1, x, y, z, domain='ZZ')" assert str(Poly(-w*x**21*y**7*z + (1 + w)*z**3 - 2*x*z + 1, x, y, z)) == \ "Poly(-w*x**21*y**7*z - 2*x*z + (w + 1)*z**3 + 1, x, y, z, domain='ZZ[w]')" assert str(Poly(x**2 + 1, x, modulus=2)) == "Poly(x**2 + 1, x, modulus=2)" assert str(Poly(2*x**2 + 3*x + 4, x, modulus=17)) == "Poly(2*x**2 + 3*x + 4, x, modulus=17)" def test_PolyRing(): assert str(ring("x", ZZ, lex)[0]) == "Polynomial ring in x over ZZ with lex order" assert str(ring("x,y", QQ, grlex)[0]) == "Polynomial ring in x, y over QQ with grlex order" assert str(ring("x,y,z", ZZ["t"], lex)[0]) == "Polynomial ring in x, y, z over ZZ[t] with lex order" def test_FracField(): assert str(field("x", ZZ, lex)[0]) == "Rational function field in x over ZZ with lex order" assert str(field("x,y", QQ, grlex)[0]) == "Rational function field in x, y over QQ with grlex order" assert str(field("x,y,z", ZZ["t"], lex)[0]) == "Rational function field in x, y, z over ZZ[t] with lex order" def test_PolyElement(): Ruv, u,v = ring("u,v", ZZ) Rxyz, x,y,z = ring("x,y,z", Ruv) Rx_zzi, xz = ring("x", ZZ_I) assert str(x - x) == "0" assert str(x - 1) == "x - 1" assert str(x + 1) == "x + 1" assert str(x**2) == "x**2" assert str(x**(-2)) == "x**(-2)" assert str(x**QQ(1, 2)) == "x**(1/2)" assert str((u**2 + 3*u*v + 1)*x**2*y + u + 1) == "(u**2 + 3*u*v + 1)*x**2*y + u + 1" assert str((u**2 + 3*u*v + 1)*x**2*y + (u + 1)*x) == "(u**2 + 3*u*v + 1)*x**2*y + (u + 1)*x" assert str((u**2 + 3*u*v + 1)*x**2*y + (u + 1)*x + 1) == "(u**2 + 3*u*v + 1)*x**2*y + (u + 1)*x + 1" assert str((-u**2 + 3*u*v - 1)*x**2*y - (u + 1)*x - 1) == "-(u**2 - 3*u*v + 1)*x**2*y - (u + 1)*x - 1" assert str(-(v**2 + v + 1)*x + 3*u*v + 1) == "-(v**2 + v + 1)*x + 3*u*v + 1" assert str(-(v**2 + v + 1)*x - 3*u*v + 1) == "-(v**2 + v + 1)*x - 3*u*v + 1" assert str((1+I)*xz + 2) == "(1 + 1*I)*x + (2 + 0*I)" def test_FracElement(): Fuv, u,v = field("u,v", ZZ) Fxyzt, x,y,z,t = field("x,y,z,t", Fuv) Rx_zzi, xz = field("x", QQ_I) i = QQ_I(0, 1) assert str(x - x) == "0" assert str(x - 1) == "x - 1" assert str(x + 1) == "x + 1" assert str(x/3) == "x/3" assert str(x/z) == "x/z" assert str(x*y/z) == "x*y/z" assert str(x/(z*t)) == "x/(z*t)" assert str(x*y/(z*t)) == "x*y/(z*t)" assert str((x - 1)/y) == "(x - 1)/y" assert str((x + 1)/y) == "(x + 1)/y" assert str((-x - 1)/y) == "(-x - 1)/y" assert str((x + 1)/(y*z)) == "(x + 1)/(y*z)" assert str(-y/(x + 1)) == "-y/(x + 1)" assert str(y*z/(x + 1)) == "y*z/(x + 1)" assert str(((u + 1)*x*y + 1)/((v - 1)*z - 1)) == "((u + 1)*x*y + 1)/((v - 1)*z - 1)" assert str(((u + 1)*x*y + 1)/((v - 1)*z - t*u*v - 1)) == "((u + 1)*x*y + 1)/((v - 1)*z - u*v*t - 1)" assert str((1+i)/xz) == "(1 + 1*I)/x" assert str(((1+i)*xz - i)/xz) == "((1 + 1*I)*x + (0 + -1*I))/x" def test_GaussianInteger(): assert str(ZZ_I(1, 0)) == "1" assert str(ZZ_I(-1, 0)) == "-1" assert str(ZZ_I(0, 1)) == "I" assert str(ZZ_I(0, -1)) == "-I" assert str(ZZ_I(0, 2)) == "2*I" assert str(ZZ_I(0, -2)) == "-2*I" assert str(ZZ_I(1, 1)) == "1 + I" assert str(ZZ_I(-1, -1)) == "-1 - I" assert str(ZZ_I(-1, -2)) == "-1 - 2*I" def test_GaussianRational(): assert str(QQ_I(1, 0)) == "1" assert str(QQ_I(QQ(2, 3), 0)) == "2/3" assert str(QQ_I(0, QQ(2, 3))) == "2*I/3" assert str(QQ_I(QQ(1, 2), QQ(-2, 3))) == "1/2 - 2*I/3" def test_Pow(): assert str(x**-1) == "1/x" assert str(x**-2) == "x**(-2)" assert str(x**2) == "x**2" assert str((x + y)**-1) == "1/(x + y)" assert str((x + y)**-2) == "(x + y)**(-2)" assert str((x + y)**2) == "(x + y)**2" assert str((x + y)**(1 + x)) == "(x + y)**(x + 1)" assert str(x**Rational(1, 3)) == "x**(1/3)" assert str(1/x**Rational(1, 3)) == "x**(-1/3)" assert str(sqrt(sqrt(x))) == "x**(1/4)" # not the same as x**-1 assert str(x**-1.0) == 'x**(-1.0)' # see issue #2860 assert str(Pow(S(2), -1.0, evaluate=False)) == '2**(-1.0)' def test_sqrt(): assert str(sqrt(x)) == "sqrt(x)" assert str(sqrt(x**2)) == "sqrt(x**2)" assert str(1/sqrt(x)) == "1/sqrt(x)" assert str(1/sqrt(x**2)) == "1/sqrt(x**2)" assert str(y/sqrt(x)) == "y/sqrt(x)" assert str(x**0.5) == "x**0.5" assert str(1/x**0.5) == "x**(-0.5)" def test_Rational(): n1 = Rational(1, 4) n2 = Rational(1, 3) n3 = Rational(2, 4) n4 = Rational(2, -4) n5 = Rational(0) n7 = Rational(3) n8 = Rational(-3) assert str(n1*n2) == "1/12" assert str(n1*n2) == "1/12" assert str(n3) == "1/2" assert str(n1*n3) == "1/8" assert str(n1 + n3) == "3/4" assert str(n1 + n2) == "7/12" assert str(n1 + n4) == "-1/4" assert str(n4*n4) == "1/4" assert str(n4 + n2) == "-1/6" assert str(n4 + n5) == "-1/2" assert str(n4*n5) == "0" assert str(n3 + n4) == "0" assert str(n1**n7) == "1/64" assert str(n2**n7) == "1/27" assert str(n2**n8) == "27" assert str(n7**n8) == "1/27" assert str(Rational("-25")) == "-25" assert str(Rational("1.25")) == "5/4" assert str(Rational("-2.6e-2")) == "-13/500" assert str(S("25/7")) == "25/7" assert str(S("-123/569")) == "-123/569" assert str(S("0.1[23]", rational=1)) == "61/495" assert str(S("5.1[666]", rational=1)) == "31/6" assert str(S("-5.1[666]", rational=1)) == "-31/6" assert str(S("0.[9]", rational=1)) == "1" assert str(S("-0.[9]", rational=1)) == "-1" assert str(sqrt(Rational(1, 4))) == "1/2" assert str(sqrt(Rational(1, 36))) == "1/6" assert str((123**25) ** Rational(1, 25)) == "123" assert str((123**25 + 1)**Rational(1, 25)) != "123" assert str((123**25 - 1)**Rational(1, 25)) != "123" assert str((123**25 - 1)**Rational(1, 25)) != "122" assert str(sqrt(Rational(81, 36))**3) == "27/8" assert str(1/sqrt(Rational(81, 36))**3) == "8/27" assert str(sqrt(-4)) == str(2*I) assert str(2**Rational(1, 10**10)) == "2**(1/10000000000)" assert sstr(Rational(2, 3), sympy_integers=True) == "S(2)/3" x = Symbol("x") assert sstr(x**Rational(2, 3), sympy_integers=True) == "x**(S(2)/3)" assert sstr(Eq(x, Rational(2, 3)), sympy_integers=True) == "Eq(x, S(2)/3)" assert sstr(Limit(x, x, Rational(7, 2)), sympy_integers=True) == \ "Limit(x, x, S(7)/2)" def test_Float(): # NOTE dps is the whole number of decimal digits assert str(Float('1.23', dps=1 + 2)) == '1.23' assert str(Float('1.23456789', dps=1 + 8)) == '1.23456789' assert str( Float('1.234567890123456789', dps=1 + 18)) == '1.234567890123456789' assert str(pi.evalf(1 + 2)) == '3.14' assert str(pi.evalf(1 + 14)) == '3.14159265358979' assert str(pi.evalf(1 + 64)) == ('3.141592653589793238462643383279' '5028841971693993751058209749445923') assert str(pi.round(-1)) == '0.0' assert str((pi**400 - (pi**400).round(1)).n(2)) == '-0.e+88' assert sstr(Float("100"), full_prec=False, min=-2, max=2) == '1.0e+2' assert sstr(Float("100"), full_prec=False, min=-2, max=3) == '100.0' assert sstr(Float("0.1"), full_prec=False, min=-2, max=3) == '0.1' assert sstr(Float("0.099"), min=-2, max=3) == '9.90000000000000e-2' def test_Relational(): assert str(Rel(x, y, "<")) == "x < y" assert str(Rel(x + y, y, "==")) == "Eq(x + y, y)" assert str(Rel(x, y, "!=")) == "Ne(x, y)" assert str(Eq(x, 1) | Eq(x, 2)) == "Eq(x, 1) | Eq(x, 2)" assert str(Ne(x, 1) & Ne(x, 2)) == "Ne(x, 1) & Ne(x, 2)" def test_AppliedBinaryRelation(): assert str(Q.eq(x, y)) == "Q.eq(x, y)" assert str(Q.ne(x, y)) == "Q.ne(x, y)" def test_CRootOf(): assert str(rootof(x**5 + 2*x - 1, 0)) == "CRootOf(x**5 + 2*x - 1, 0)" def test_RootSum(): f = x**5 + 2*x - 1 assert str( RootSum(f, Lambda(z, z), auto=False)) == "RootSum(x**5 + 2*x - 1)" assert str(RootSum(f, Lambda( z, z**2), auto=False)) == "RootSum(x**5 + 2*x - 1, Lambda(z, z**2))" def test_GroebnerBasis(): assert str(groebner( [], x, y)) == "GroebnerBasis([], x, y, domain='ZZ', order='lex')" F = [x**2 - 3*y - x + 1, y**2 - 2*x + y - 1] assert str(groebner(F, order='grlex')) == \ "GroebnerBasis([x**2 - x - 3*y + 1, y**2 - 2*x + y - 1], x, y, domain='ZZ', order='grlex')" assert str(groebner(F, order='lex')) == \ "GroebnerBasis([2*x - y**2 - y + 1, y**4 + 2*y**3 - 3*y**2 - 16*y + 7], x, y, domain='ZZ', order='lex')" def test_set(): assert sstr(set()) == 'set()' assert sstr(frozenset()) == 'frozenset()' assert sstr({1}) == '{1}' assert sstr(frozenset([1])) == 'frozenset({1})' assert sstr({1, 2, 3}) == '{1, 2, 3}' assert sstr(frozenset([1, 2, 3])) == 'frozenset({1, 2, 3})' assert sstr( {1, x, x**2, x**3, x**4}) == '{1, x, x**2, x**3, x**4}' assert sstr( frozenset([1, x, x**2, x**3, x**4])) == 'frozenset({1, x, x**2, x**3, x**4})' def test_SparseMatrix(): M = SparseMatrix([[x**+1, 1], [y, x + y]]) assert str(M) == "Matrix([[x, 1], [y, x + y]])" assert sstr(M) == "Matrix([\n[x, 1],\n[y, x + y]])" def test_Sum(): assert str(summation(cos(3*z), (z, x, y))) == "Sum(cos(3*z), (z, x, y))" assert str(Sum(x*y**2, (x, -2, 2), (y, -5, 5))) == \ "Sum(x*y**2, (x, -2, 2), (y, -5, 5))" def test_Symbol(): assert str(y) == "y" assert str(x) == "x" e = x assert str(e) == "x" def test_tuple(): assert str((x,)) == sstr((x,)) == "(x,)" assert str((x + y, 1 + x)) == sstr((x + y, 1 + x)) == "(x + y, x + 1)" assert str((x + y, ( 1 + x, x**2))) == sstr((x + y, (1 + x, x**2))) == "(x + y, (x + 1, x**2))" def test_Series_str(): tf1 = TransferFunction(x*y**2 - z, y**3 - t**3, y) tf2 = TransferFunction(x - y, x + y, y) tf3 = TransferFunction(t*x**2 - t**w*x + w, t - y, y) assert str(Series(tf1, tf2)) == \ "Series(TransferFunction(x*y**2 - z, -t**3 + y**3, y), TransferFunction(x - y, x + y, y))" assert str(Series(tf1, tf2, tf3)) == \ "Series(TransferFunction(x*y**2 - z, -t**3 + y**3, y), TransferFunction(x - y, x + y, y), TransferFunction(t*x**2 - t**w*x + w, t - y, y))" assert str(Series(-tf2, tf1)) == \ "Series(TransferFunction(-x + y, x + y, y), TransferFunction(x*y**2 - z, -t**3 + y**3, y))" def test_TransferFunction_str(): tf1 = TransferFunction(x - 1, x + 1, x) assert str(tf1) == "TransferFunction(x - 1, x + 1, x)" tf2 = TransferFunction(x + 1, 2 - y, x) assert str(tf2) == "TransferFunction(x + 1, 2 - y, x)" tf3 = TransferFunction(y, y**2 + 2*y + 3, y) assert str(tf3) == "TransferFunction(y, y**2 + 2*y + 3, y)" def test_Parallel_str(): tf1 = TransferFunction(x*y**2 - z, y**3 - t**3, y) tf2 = TransferFunction(x - y, x + y, y) tf3 = TransferFunction(t*x**2 - t**w*x + w, t - y, y) assert str(Parallel(tf1, tf2)) == \ "Parallel(TransferFunction(x*y**2 - z, -t**3 + y**3, y), TransferFunction(x - y, x + y, y))" assert str(Parallel(tf1, tf2, tf3)) == \ "Parallel(TransferFunction(x*y**2 - z, -t**3 + y**3, y), TransferFunction(x - y, x + y, y), TransferFunction(t*x**2 - t**w*x + w, t - y, y))" assert str(Parallel(-tf2, tf1)) == \ "Parallel(TransferFunction(-x + y, x + y, y), TransferFunction(x*y**2 - z, -t**3 + y**3, y))" def test_Feedback_str(): tf1 = TransferFunction(x*y**2 - z, y**3 - t**3, y) tf2 = TransferFunction(x - y, x + y, y) tf3 = TransferFunction(t*x**2 - t**w*x + w, t - y, y) assert str(Feedback(tf1*tf2, tf3)) == \ "Feedback(Series(TransferFunction(x*y**2 - z, -t**3 + y**3, y), TransferFunction(x - y, x + y, y)), TransferFunction(t*x**2 - t**w*x + w, t - y, y))" assert str(Feedback(tf1, TransferFunction(1, 1, y))) == \ "Feedback(TransferFunction(x*y**2 - z, -t**3 + y**3, y), TransferFunction(1, 1, y))" def test_Quaternion_str_printer(): q = Quaternion(x, y, z, t) assert str(q) == "x + y*i + z*j + t*k" q = Quaternion(x,y,z,x*t) assert str(q) == "x + y*i + z*j + t*x*k" q = Quaternion(x,y,z,x+t) assert str(q) == "x + y*i + z*j + (t + x)*k" def test_Quantity_str(): assert sstr(second, abbrev=True) == "s" assert sstr(joule, abbrev=True) == "J" assert str(second) == "second" assert str(joule) == "joule" def test_wild_str(): # Check expressions containing Wild not causing infinite recursion w = Wild('x') assert str(w + 1) == 'x_ + 1' assert str(exp(2**w) + 5) == 'exp(2**x_) + 5' assert str(3*w + 1) == '3*x_ + 1' assert str(1/w + 1) == '1 + 1/x_' assert str(w**2 + 1) == 'x_**2 + 1' assert str(1/(1 - w)) == '1/(1 - x_)' def test_wild_matchpy(): from sympy.utilities.matchpy_connector import WildDot, WildPlus, WildStar matchpy = import_module("matchpy") if matchpy is None: return wd = WildDot('w_') wp = WildPlus('w__') ws = WildStar('w___') assert str(wd) == 'w_' assert str(wp) == 'w__' assert str(ws) == 'w___' assert str(wp/ws + 2**wd) == '2**w_ + w__/w___' assert str(sin(wd)*cos(wp)*sqrt(ws)) == 'sqrt(w___)*sin(w_)*cos(w__)' def test_zeta(): assert str(zeta(3)) == "zeta(3)" def test_issue_3101(): e = x - y a = str(e) b = str(e) assert a == b def test_issue_3103(): e = -2*sqrt(x) - y/sqrt(x)/2 assert str(e) not in ["(-2)*x**1/2(-1/2)*x**(-1/2)*y", "-2*x**1/2(-1/2)*x**(-1/2)*y", "-2*x**1/2-1/2*x**-1/2*w"] assert str(e) == "-2*sqrt(x) - y/(2*sqrt(x))" def test_issue_4021(): e = Integral(x, x) + 1 assert str(e) == 'Integral(x, x) + 1' def test_sstrrepr(): assert sstr('abc') == 'abc' assert sstrrepr('abc') == "'abc'" e = ['a', 'b', 'c', x] assert sstr(e) == "[a, b, c, x]" assert sstrrepr(e) == "['a', 'b', 'c', x]" def test_infinity(): assert sstr(oo*I) == "oo*I" def test_full_prec(): assert sstr(S("0.3"), full_prec=True) == "0.300000000000000" assert sstr(S("0.3"), full_prec="auto") == "0.300000000000000" assert sstr(S("0.3"), full_prec=False) == "0.3" assert sstr(S("0.3")*x, full_prec=True) in [ "0.300000000000000*x", "x*0.300000000000000" ] assert sstr(S("0.3")*x, full_prec="auto") in [ "0.3*x", "x*0.3" ] assert sstr(S("0.3")*x, full_prec=False) in [ "0.3*x", "x*0.3" ] def test_noncommutative(): A, B, C = symbols('A,B,C', commutative=False) assert sstr(A*B*C**-1) == "A*B*C**(-1)" assert sstr(C**-1*A*B) == "C**(-1)*A*B" assert sstr(A*C**-1*B) == "A*C**(-1)*B" assert sstr(sqrt(A)) == "sqrt(A)" assert sstr(1/sqrt(A)) == "A**(-1/2)" def test_empty_printer(): str_printer = StrPrinter() assert str_printer.emptyPrinter("foo") == "foo" assert str_printer.emptyPrinter(x*y) == "x*y" assert str_printer.emptyPrinter(32) == "32" def test_settings(): raises(TypeError, lambda: sstr(S(4), method="garbage")) def test_RandomDomain(): from sympy.stats import Normal, Die, Exponential, pspace, where X = Normal('x1', 0, 1) assert str(where(X > 0)) == "Domain: (0 < x1) & (x1 < oo)" D = Die('d1', 6) assert str(where(D > 4)) == "Domain: Eq(d1, 5) | Eq(d1, 6)" A = Exponential('a', 1) B = Exponential('b', 1) assert str(pspace(Tuple(A, B)).domain) == "Domain: (0 <= a) & (0 <= b) & (a < oo) & (b < oo)" def test_FiniteSet(): assert str(FiniteSet(*range(1, 51))) == ( 'FiniteSet(1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17,' ' 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34,' ' 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50)' ) assert str(FiniteSet(*range(1, 6))) == 'FiniteSet(1, 2, 3, 4, 5)' def test_UniversalSet(): assert str(S.UniversalSet) == 'UniversalSet' def test_PrettyPoly(): from sympy.polys.domains import QQ F = QQ.frac_field(x, y) R = QQ[x, y] assert sstr(F.convert(x/(x + y))) == sstr(x/(x + y)) assert sstr(R.convert(x + y)) == sstr(x + y) def test_categories(): from sympy.categories import (Object, NamedMorphism, IdentityMorphism, Category) A = Object("A") B = Object("B") f = NamedMorphism(A, B, "f") id_A = IdentityMorphism(A) K = Category("K") assert str(A) == 'Object("A")' assert str(f) == 'NamedMorphism(Object("A"), Object("B"), "f")' assert str(id_A) == 'IdentityMorphism(Object("A"))' assert str(K) == 'Category("K")' def test_Tr(): A, B = symbols('A B', commutative=False) t = Tr(A*B) assert str(t) == 'Tr(A*B)' def test_issue_6387(): assert str(factor(-3.0*z + 3)) == '-3.0*(1.0*z - 1.0)' def test_MatMul_MatAdd(): from sympy import MatrixSymbol X, Y = MatrixSymbol("X", 2, 2), MatrixSymbol("Y", 2, 2) assert str(2*(X + Y)) == "2*X + 2*Y" assert str(I*X) == "I*X" assert str(-I*X) == "-I*X" assert str((1 + I)*X) == '(1 + I)*X' assert str(-(1 + I)*X) == '(-1 - I)*X' def test_MatrixSlice(): n = Symbol('n', integer=True) X = MatrixSymbol('X', n, n) Y = MatrixSymbol('Y', 10, 10) Z = MatrixSymbol('Z', 10, 10) assert str(MatrixSlice(X, (None, None, None), (None, None, None))) == 'X[:, :]' assert str(X[x:x + 1, y:y + 1]) == 'X[x:x + 1, y:y + 1]' assert str(X[x:x + 1:2, y:y + 1:2]) == 'X[x:x + 1:2, y:y + 1:2]' assert str(X[:x, y:]) == 'X[:x, y:]' assert str(X[:x, y:]) == 'X[:x, y:]' assert str(X[x:, :y]) == 'X[x:, :y]' assert str(X[x:y, z:w]) == 'X[x:y, z:w]' assert str(X[x:y:t, w:t:x]) == 'X[x:y:t, w:t:x]' assert str(X[x::y, t::w]) == 'X[x::y, t::w]' assert str(X[:x:y, :t:w]) == 'X[:x:y, :t:w]' assert str(X[::x, ::y]) == 'X[::x, ::y]' assert str(MatrixSlice(X, (0, None, None), (0, None, None))) == 'X[:, :]' assert str(MatrixSlice(X, (None, n, None), (None, n, None))) == 'X[:, :]' assert str(MatrixSlice(X, (0, n, None), (0, n, None))) == 'X[:, :]' assert str(MatrixSlice(X, (0, n, 2), (0, n, 2))) == 'X[::2, ::2]' assert str(X[1:2:3, 4:5:6]) == 'X[1:2:3, 4:5:6]' assert str(X[1:3:5, 4:6:8]) == 'X[1:3:5, 4:6:8]' assert str(X[1:10:2]) == 'X[1:10:2, :]' assert str(Y[:5, 1:9:2]) == 'Y[:5, 1:9:2]' assert str(Y[:5, 1:10:2]) == 'Y[:5, 1::2]' assert str(Y[5, :5:2]) == 'Y[5:6, :5:2]' assert str(X[0:1, 0:1]) == 'X[:1, :1]' assert str(X[0:1:2, 0:1:2]) == 'X[:1:2, :1:2]' assert str((Y + Z)[2:, 2:]) == '(Y + Z)[2:, 2:]' def test_true_false(): assert str(true) == repr(true) == sstr(true) == "True" assert str(false) == repr(false) == sstr(false) == "False" def test_Equivalent(): assert str(Equivalent(y, x)) == "Equivalent(x, y)" def test_Xor(): assert str(Xor(y, x, evaluate=False)) == "x ^ y" def test_Complement(): assert str(Complement(S.Reals, S.Naturals)) == 'Complement(Reals, Naturals)' def test_SymmetricDifference(): assert str(SymmetricDifference(Interval(2, 3), Interval(3, 4),evaluate=False)) == \ 'SymmetricDifference(Interval(2, 3), Interval(3, 4))' def test_UnevaluatedExpr(): a, b = symbols("a b") expr1 = 2*UnevaluatedExpr(a+b) assert str(expr1) == "2*(a + b)" def test_MatrixElement_printing(): # test cases for issue #11821 A = MatrixSymbol("A", 1, 3) B = MatrixSymbol("B", 1, 3) C = MatrixSymbol("C", 1, 3) assert(str(A[0, 0]) == "A[0, 0]") assert(str(3 * A[0, 0]) == "3*A[0, 0]") F = C[0, 0].subs(C, A - B) assert str(F) == "(A - B)[0, 0]" def test_MatrixSymbol_printing(): A = MatrixSymbol("A", 3, 3) B = MatrixSymbol("B", 3, 3) assert str(A - A*B - B) == "A - A*B - B" assert str(A*B - (A+B)) == "-A + A*B - B" assert str(A**(-1)) == "A**(-1)" assert str(A**3) == "A**3" def test_MatrixExpressions(): n = Symbol('n', integer=True) X = MatrixSymbol('X', n, n) assert str(X) == "X" # Apply function elementwise (`ElementwiseApplyFunc`): expr = (X.T*X).applyfunc(sin) assert str(expr) == 'Lambda(_d, sin(_d)).(X.T*X)' lamda = Lambda(x, 1/x) expr = (n*X).applyfunc(lamda) assert str(expr) == 'Lambda(x, 1/x).(n*X)' def test_Subs_printing(): assert str(Subs(x, (x,), (1,))) == 'Subs(x, x, 1)' assert str(Subs(x + y, (x, y), (1, 2))) == 'Subs(x + y, (x, y), (1, 2))' def test_issue_15716(): e = Integral(factorial(x), (x, -oo, oo)) assert e.as_terms() == ([(e, ((1.0, 0.0), (1,), ()))], [e]) def test_str_special_matrices(): from sympy.matrices import Identity, ZeroMatrix, OneMatrix assert str(Identity(4)) == 'I' assert str(ZeroMatrix(2, 2)) == '0' assert str(OneMatrix(2, 2)) == '1' def test_issue_14567(): assert factorial(Sum(-1, (x, 0, 0))) + y # doesn't raise an error def test_issue_21119_21460(): ss = lambda x: str(S(x, evaluate=False)) assert ss('4/2') == '4/2' assert ss('4/-2') == '4/(-2)' assert ss('-4/2') == '-4/2' assert ss('-4/-2') == '-4/(-2)' assert ss('-2*3/-1') == '-2*3/(-1)' assert ss('-2*3/-1/2') == '-2*3/(-1*2)' assert ss('4/2/1') == '4/(2*1)' assert ss('-2/-1/2') == '-2/(-1*2)' assert ss('2*3*4**(-2*3)') == '2*3/4**(2*3)' assert ss('2*3*1*4**(-2*3)') == '2*3*1/4**(2*3)' def test_Str(): from sympy.core.symbol import Str assert str(Str('x')) == 'x' assert sstrrepr(Str('x')) == "Str('x')" def test_diffgeom(): from sympy.diffgeom import Manifold, Patch, CoordSystem, BaseScalarField x,y = symbols('x y', real=True) m = Manifold('M', 2) assert str(m) == "M" p = Patch('P', m) assert str(p) == "P" rect = CoordSystem('rect', p, [x, y]) assert str(rect) == "rect" b = BaseScalarField(rect, 0) assert str(b) == "x" def test_NDimArray(): assert sstr(NDimArray(1.0), full_prec=True) == '1.00000000000000' assert sstr(NDimArray(1.0), full_prec=False) == '1.0' assert sstr(NDimArray([1.0, 2.0]), full_prec=True) == '[1.00000000000000, 2.00000000000000]' assert sstr(NDimArray([1.0, 2.0]), full_prec=False) == '[1.0, 2.0]' def test_Predicate(): assert sstr(Q.even) == 'Q.even' def test_AppliedPredicate(): assert sstr(Q.even(x)) == 'Q.even(x)' def test_printing_str_array_expressions(): assert sstr(ArraySymbol("A", 2, 3, 4)) == "A" assert sstr(ArrayElement("A", (2, 1/(1-x), 0))) == "A[2, 1/(1 - x), 0]"
47010335bfc8ac34dfeca1123244917955624f68973deff3244951c50c4ded01
from sympy import symbols, sin, Matrix, Interval, Piecewise, Sum, lambdify, \ Expr, sqrt from sympy.testing.pytest import raises from sympy.printing.tensorflow import TensorflowPrinter from sympy.printing.lambdarepr import lambdarepr, LambdaPrinter, NumExprPrinter x, y, z = symbols("x,y,z") i, a, b = symbols("i,a,b") j, c, d = symbols("j,c,d") def test_basic(): assert lambdarepr(x*y) == "x*y" assert lambdarepr(x + y) in ["y + x", "x + y"] assert lambdarepr(x**y) == "x**y" def test_matrix(): A = Matrix([[x, y], [y*x, z**2]]) # assert lambdarepr(A) == "ImmutableDenseMatrix([[x, y], [x*y, z**2]])" # Test printing a Matrix that has an element that is printed differently # with the LambdaPrinter than in the StrPrinter. p = Piecewise((x, True), evaluate=False) A = Matrix([p]) assert lambdarepr(A) == "ImmutableDenseMatrix([[((x))]])" def test_piecewise(): # In each case, test eval() the lambdarepr() to make sure there are a # correct number of parentheses. It will give a SyntaxError if there aren't. h = "lambda x: " p = Piecewise((x, True), evaluate=False) l = lambdarepr(p) eval(h + l) assert l == "((x))" p = Piecewise((x, x < 0)) l = lambdarepr(p) eval(h + l) assert l == "((x) if (x < 0) else None)" p = Piecewise( (1, x < 1), (2, x < 2), (0, True) ) l = lambdarepr(p) eval(h + l) assert l == "((1) if (x < 1) else (2) if (x < 2) else (0))" p = Piecewise( (1, x < 1), (2, x < 2), ) l = lambdarepr(p) eval(h + l) assert l == "((1) if (x < 1) else (2) if (x < 2) else None)" p = Piecewise( (x, x < 1), (x**2, Interval(3, 4, True, False).contains(x)), (0, True), ) l = lambdarepr(p) eval(h + l) assert l == "((x) if (x < 1) else (x**2) if (((x <= 4)) and ((x > 3))) else (0))" p = Piecewise( (x**2, x < 0), (x, x < 1), (2 - x, x >= 1), (0, True), evaluate=False ) l = lambdarepr(p) eval(h + l) assert l == "((x**2) if (x < 0) else (x) if (x < 1)"\ " else (2 - x) if (x >= 1) else (0))" p = Piecewise( (x**2, x < 0), (x, x < 1), (2 - x, x >= 1), evaluate=False ) l = lambdarepr(p) eval(h + l) assert l == "((x**2) if (x < 0) else (x) if (x < 1)"\ " else (2 - x) if (x >= 1) else None)" p = Piecewise( (1, x >= 1), (2, x >= 2), (3, x >= 3), (4, x >= 4), (5, x >= 5), (6, True) ) l = lambdarepr(p) eval(h + l) assert l == "((1) if (x >= 1) else (2) if (x >= 2) else (3) if (x >= 3)"\ " else (4) if (x >= 4) else (5) if (x >= 5) else (6))" p = Piecewise( (1, x <= 1), (2, x <= 2), (3, x <= 3), (4, x <= 4), (5, x <= 5), (6, True) ) l = lambdarepr(p) eval(h + l) assert l == "((1) if (x <= 1) else (2) if (x <= 2) else (3) if (x <= 3)"\ " else (4) if (x <= 4) else (5) if (x <= 5) else (6))" p = Piecewise( (1, x > 1), (2, x > 2), (3, x > 3), (4, x > 4), (5, x > 5), (6, True) ) l = lambdarepr(p) eval(h + l) assert l =="((1) if (x > 1) else (2) if (x > 2) else (3) if (x > 3)"\ " else (4) if (x > 4) else (5) if (x > 5) else (6))" p = Piecewise( (1, x < 1), (2, x < 2), (3, x < 3), (4, x < 4), (5, x < 5), (6, True) ) l = lambdarepr(p) eval(h + l) assert l == "((1) if (x < 1) else (2) if (x < 2) else (3) if (x < 3)"\ " else (4) if (x < 4) else (5) if (x < 5) else (6))" p = Piecewise( (Piecewise( (1, x > 0), (2, True) ), y > 0), (3, True) ) l = lambdarepr(p) eval(h + l) assert l == "((((1) if (x > 0) else (2))) if (y > 0) else (3))" def test_sum__1(): # In each case, test eval() the lambdarepr() to make sure that # it evaluates to the same results as the symbolic expression s = Sum(x ** i, (i, a, b)) l = lambdarepr(s) assert l == "(builtins.sum(x**i for i in range(a, b+1)))" args = x, a, b f = lambdify(args, s) v = 2, 3, 8 assert f(*v) == s.subs(zip(args, v)).doit() def test_sum__2(): s = Sum(i * x, (i, a, b)) l = lambdarepr(s) assert l == "(builtins.sum(i*x for i in range(a, b+1)))" args = x, a, b f = lambdify(args, s) v = 2, 3, 8 assert f(*v) == s.subs(zip(args, v)).doit() def test_multiple_sums(): s = Sum(i * x + j, (i, a, b), (j, c, d)) l = lambdarepr(s) assert l == "(builtins.sum(i*x + j for i in range(a, b+1) for j in range(c, d+1)))" args = x, a, b, c, d f = lambdify(args, s) vals = 2, 3, 4, 5, 6 f_ref = s.subs(zip(args, vals)).doit() f_res = f(*vals) assert f_res == f_ref def test_sqrt(): prntr = LambdaPrinter({'standard' : 'python2'}) assert prntr._print_Pow(sqrt(x), rational=False) == 'sqrt(x)' assert prntr._print_Pow(sqrt(x), rational=True) == 'x**(1./2.)' prntr = LambdaPrinter({'standard' : 'python3'}) assert prntr._print_Pow(sqrt(x), rational=True) == 'x**(1/2)' def test_settings(): raises(TypeError, lambda: lambdarepr(sin(x), method="garbage")) def test_numexpr(): # test ITE rewrite as Piecewise from sympy.logic.boolalg import ITE expr = ITE(x > 0, True, False, evaluate=False) assert NumExprPrinter().doprint(expr) == \ "evaluate('where((x > 0), True, False)', truediv=True)" class CustomPrintedObject(Expr): def _lambdacode(self, printer): return 'lambda' def _tensorflowcode(self, printer): return 'tensorflow' def _numpycode(self, printer): return 'numpy' def _numexprcode(self, printer): return 'numexpr' def _mpmathcode(self, printer): return 'mpmath' def test_printmethod(): # In each case, printmethod is called to test # its working obj = CustomPrintedObject() assert LambdaPrinter().doprint(obj) == 'lambda' assert TensorflowPrinter().doprint(obj) == 'tensorflow' assert NumExprPrinter().doprint(obj) == "evaluate('numexpr', truediv=True)" assert NumExprPrinter().doprint(Piecewise((y, x >= 0), (z, x < 0))) == \ "evaluate('where((x >= 0), y, z)', truediv=True)"
5a840740247935d1d23b909e129d6194ab70a7ec91dda7fc1590578789ead7e5
from sympy import diff, Integral, Limit, sin, Symbol, Integer, Rational, cos, \ tan, asin, acos, atan, sinh, cosh, tanh, asinh, acosh, atanh, E, I, oo, \ pi, GoldenRatio, EulerGamma, Sum, Eq, Ne, Ge, Lt, Float, Matrix, Basic, \ S, MatrixSymbol, Function, Derivative, log, true, false, Range, Min, Max, \ Lambda, IndexedBase, symbols, zoo, elliptic_f, elliptic_e, elliptic_pi, Ei, \ expint, jacobi, gegenbauer, chebyshevt, chebyshevu, legendre, assoc_legendre, \ laguerre, assoc_laguerre, hermite, euler, stieltjes, mathieuc, mathieus, \ mathieucprime, mathieusprime, TribonacciConstant, Contains, LambertW, \ cot, coth, acot, acoth, csc, acsc, csch, acsch, sec, asec, sech, asech from sympy import elliptic_k, totient, reduced_totient, primenu, primeomega, \ fresnelc, fresnels, Heaviside from sympy.calculus.util import AccumBounds from sympy.core.containers import Tuple from sympy.functions.combinatorial.factorials import factorial, factorial2, \ binomial from sympy.functions.combinatorial.numbers import bernoulli, bell, lucas, \ fibonacci, tribonacci, catalan from sympy.functions.elementary.complexes import re, im, Abs, conjugate from sympy.functions.elementary.exponential import exp from sympy.functions.elementary.integers import floor, ceiling from sympy.functions.special.gamma_functions import gamma, lowergamma, uppergamma from sympy.functions.special.singularity_functions import SingularityFunction from sympy.functions.special.zeta_functions import polylog, lerchphi, zeta, dirichlet_eta from sympy.logic.boolalg import And, Or, Implies, Equivalent, Xor, Not from sympy.matrices.expressions.determinant import Determinant from sympy.physics.quantum import ComplexSpace, HilbertSpace, FockSpace, hbar, Dagger from sympy.printing.mathml import mathml, MathMLContentPrinter, \ MathMLPresentationPrinter, MathMLPrinter from sympy.sets.sets import FiniteSet, Union, Intersection, Complement, \ SymmetricDifference, Interval, EmptySet, ProductSet from sympy.stats.rv import RandomSymbol from sympy.testing.pytest import raises from sympy.vector import CoordSys3D, Cross, Curl, Dot, Divergence, Gradient, Laplacian from sympy import sympify x, y, z, a, b, c, d, e, n = symbols('x:z a:e n') mp = MathMLContentPrinter() mpp = MathMLPresentationPrinter() def test_mathml_printer(): m = MathMLPrinter() assert m.doprint(1+x) == mp.doprint(1+x) def test_content_printmethod(): assert mp.doprint(1 + x) == '<apply><plus/><ci>x</ci><cn>1</cn></apply>' def test_content_mathml_core(): mml_1 = mp._print(1 + x) assert mml_1.nodeName == 'apply' nodes = mml_1.childNodes assert len(nodes) == 3 assert nodes[0].nodeName == 'plus' assert nodes[0].hasChildNodes() is False assert nodes[0].nodeValue is None assert nodes[1].nodeName in ['cn', 'ci'] if nodes[1].nodeName == 'cn': assert nodes[1].childNodes[0].nodeValue == '1' assert nodes[2].childNodes[0].nodeValue == 'x' else: assert nodes[1].childNodes[0].nodeValue == 'x' assert nodes[2].childNodes[0].nodeValue == '1' mml_2 = mp._print(x**2) assert mml_2.nodeName == 'apply' nodes = mml_2.childNodes assert nodes[1].childNodes[0].nodeValue == 'x' assert nodes[2].childNodes[0].nodeValue == '2' mml_3 = mp._print(2*x) assert mml_3.nodeName == 'apply' nodes = mml_3.childNodes assert nodes[0].nodeName == 'times' assert nodes[1].childNodes[0].nodeValue == '2' assert nodes[2].childNodes[0].nodeValue == 'x' mml = mp._print(Float(1.0, 2)*x) assert mml.nodeName == 'apply' nodes = mml.childNodes assert nodes[0].nodeName == 'times' assert nodes[1].childNodes[0].nodeValue == '1.0' assert nodes[2].childNodes[0].nodeValue == 'x' def test_content_mathml_functions(): mml_1 = mp._print(sin(x)) assert mml_1.nodeName == 'apply' assert mml_1.childNodes[0].nodeName == 'sin' assert mml_1.childNodes[1].nodeName == 'ci' mml_2 = mp._print(diff(sin(x), x, evaluate=False)) assert mml_2.nodeName == 'apply' assert mml_2.childNodes[0].nodeName == 'diff' assert mml_2.childNodes[1].nodeName == 'bvar' assert mml_2.childNodes[1].childNodes[ 0].nodeName == 'ci' # below bvar there's <ci>x/ci> mml_3 = mp._print(diff(cos(x*y), x, evaluate=False)) assert mml_3.nodeName == 'apply' assert mml_3.childNodes[0].nodeName == 'partialdiff' assert mml_3.childNodes[1].nodeName == 'bvar' assert mml_3.childNodes[1].childNodes[ 0].nodeName == 'ci' # below bvar there's <ci>x/ci> def test_content_mathml_limits(): # XXX No unevaluated limits lim_fun = sin(x)/x mml_1 = mp._print(Limit(lim_fun, x, 0)) assert mml_1.childNodes[0].nodeName == 'limit' assert mml_1.childNodes[1].nodeName == 'bvar' assert mml_1.childNodes[2].nodeName == 'lowlimit' assert mml_1.childNodes[3].toxml() == mp._print(lim_fun).toxml() def test_content_mathml_integrals(): integrand = x mml_1 = mp._print(Integral(integrand, (x, 0, 1))) assert mml_1.childNodes[0].nodeName == 'int' assert mml_1.childNodes[1].nodeName == 'bvar' assert mml_1.childNodes[2].nodeName == 'lowlimit' assert mml_1.childNodes[3].nodeName == 'uplimit' assert mml_1.childNodes[4].toxml() == mp._print(integrand).toxml() def test_content_mathml_matrices(): A = Matrix([1, 2, 3]) B = Matrix([[0, 5, 4], [2, 3, 1], [9, 7, 9]]) mll_1 = mp._print(A) assert mll_1.childNodes[0].nodeName == 'matrixrow' assert mll_1.childNodes[0].childNodes[0].nodeName == 'cn' assert mll_1.childNodes[0].childNodes[0].childNodes[0].nodeValue == '1' assert mll_1.childNodes[1].nodeName == 'matrixrow' assert mll_1.childNodes[1].childNodes[0].nodeName == 'cn' assert mll_1.childNodes[1].childNodes[0].childNodes[0].nodeValue == '2' assert mll_1.childNodes[2].nodeName == 'matrixrow' assert mll_1.childNodes[2].childNodes[0].nodeName == 'cn' assert mll_1.childNodes[2].childNodes[0].childNodes[0].nodeValue == '3' mll_2 = mp._print(B) assert mll_2.childNodes[0].nodeName == 'matrixrow' assert mll_2.childNodes[0].childNodes[0].nodeName == 'cn' assert mll_2.childNodes[0].childNodes[0].childNodes[0].nodeValue == '0' assert mll_2.childNodes[0].childNodes[1].nodeName == 'cn' assert mll_2.childNodes[0].childNodes[1].childNodes[0].nodeValue == '5' assert mll_2.childNodes[0].childNodes[2].nodeName == 'cn' assert mll_2.childNodes[0].childNodes[2].childNodes[0].nodeValue == '4' assert mll_2.childNodes[1].nodeName == 'matrixrow' assert mll_2.childNodes[1].childNodes[0].nodeName == 'cn' assert mll_2.childNodes[1].childNodes[0].childNodes[0].nodeValue == '2' assert mll_2.childNodes[1].childNodes[1].nodeName == 'cn' assert mll_2.childNodes[1].childNodes[1].childNodes[0].nodeValue == '3' assert mll_2.childNodes[1].childNodes[2].nodeName == 'cn' assert mll_2.childNodes[1].childNodes[2].childNodes[0].nodeValue == '1' assert mll_2.childNodes[2].nodeName == 'matrixrow' assert mll_2.childNodes[2].childNodes[0].nodeName == 'cn' assert mll_2.childNodes[2].childNodes[0].childNodes[0].nodeValue == '9' assert mll_2.childNodes[2].childNodes[1].nodeName == 'cn' assert mll_2.childNodes[2].childNodes[1].childNodes[0].nodeValue == '7' assert mll_2.childNodes[2].childNodes[2].nodeName == 'cn' assert mll_2.childNodes[2].childNodes[2].childNodes[0].nodeValue == '9' def test_content_mathml_sums(): summand = x mml_1 = mp._print(Sum(summand, (x, 1, 10))) assert mml_1.childNodes[0].nodeName == 'sum' assert mml_1.childNodes[1].nodeName == 'bvar' assert mml_1.childNodes[2].nodeName == 'lowlimit' assert mml_1.childNodes[3].nodeName == 'uplimit' assert mml_1.childNodes[4].toxml() == mp._print(summand).toxml() def test_content_mathml_tuples(): mml_1 = mp._print([2]) assert mml_1.nodeName == 'list' assert mml_1.childNodes[0].nodeName == 'cn' assert len(mml_1.childNodes) == 1 mml_2 = mp._print([2, Integer(1)]) assert mml_2.nodeName == 'list' assert mml_2.childNodes[0].nodeName == 'cn' assert mml_2.childNodes[1].nodeName == 'cn' assert len(mml_2.childNodes) == 2 def test_content_mathml_add(): mml = mp._print(x**5 - x**4 + x) assert mml.childNodes[0].nodeName == 'plus' assert mml.childNodes[1].childNodes[0].nodeName == 'minus' assert mml.childNodes[1].childNodes[1].nodeName == 'apply' def test_content_mathml_Rational(): mml_1 = mp._print(Rational(1, 1)) """should just return a number""" assert mml_1.nodeName == 'cn' mml_2 = mp._print(Rational(2, 5)) assert mml_2.childNodes[0].nodeName == 'divide' def test_content_mathml_constants(): mml = mp._print(I) assert mml.nodeName == 'imaginaryi' mml = mp._print(E) assert mml.nodeName == 'exponentiale' mml = mp._print(oo) assert mml.nodeName == 'infinity' mml = mp._print(pi) assert mml.nodeName == 'pi' assert mathml(GoldenRatio) == '<cn>&#966;</cn>' mml = mathml(EulerGamma) assert mml == '<eulergamma/>' mml = mathml(EmptySet()) assert mml == '<emptyset/>' mml = mathml(S.true) assert mml == '<true/>' mml = mathml(S.false) assert mml == '<false/>' mml = mathml(S.NaN) assert mml == '<notanumber/>' def test_content_mathml_trig(): mml = mp._print(sin(x)) assert mml.childNodes[0].nodeName == 'sin' mml = mp._print(cos(x)) assert mml.childNodes[0].nodeName == 'cos' mml = mp._print(tan(x)) assert mml.childNodes[0].nodeName == 'tan' mml = mp._print(cot(x)) assert mml.childNodes[0].nodeName == 'cot' mml = mp._print(csc(x)) assert mml.childNodes[0].nodeName == 'csc' mml = mp._print(sec(x)) assert mml.childNodes[0].nodeName == 'sec' mml = mp._print(asin(x)) assert mml.childNodes[0].nodeName == 'arcsin' mml = mp._print(acos(x)) assert mml.childNodes[0].nodeName == 'arccos' mml = mp._print(atan(x)) assert mml.childNodes[0].nodeName == 'arctan' mml = mp._print(acot(x)) assert mml.childNodes[0].nodeName == 'arccot' mml = mp._print(acsc(x)) assert mml.childNodes[0].nodeName == 'arccsc' mml = mp._print(asec(x)) assert mml.childNodes[0].nodeName == 'arcsec' mml = mp._print(sinh(x)) assert mml.childNodes[0].nodeName == 'sinh' mml = mp._print(cosh(x)) assert mml.childNodes[0].nodeName == 'cosh' mml = mp._print(tanh(x)) assert mml.childNodes[0].nodeName == 'tanh' mml = mp._print(coth(x)) assert mml.childNodes[0].nodeName == 'coth' mml = mp._print(csch(x)) assert mml.childNodes[0].nodeName == 'csch' mml = mp._print(sech(x)) assert mml.childNodes[0].nodeName == 'sech' mml = mp._print(asinh(x)) assert mml.childNodes[0].nodeName == 'arcsinh' mml = mp._print(atanh(x)) assert mml.childNodes[0].nodeName == 'arctanh' mml = mp._print(acosh(x)) assert mml.childNodes[0].nodeName == 'arccosh' mml = mp._print(acoth(x)) assert mml.childNodes[0].nodeName == 'arccoth' mml = mp._print(acsch(x)) assert mml.childNodes[0].nodeName == 'arccsch' mml = mp._print(asech(x)) assert mml.childNodes[0].nodeName == 'arcsech' def test_content_mathml_relational(): mml_1 = mp._print(Eq(x, 1)) assert mml_1.nodeName == 'apply' assert mml_1.childNodes[0].nodeName == 'eq' assert mml_1.childNodes[1].nodeName == 'ci' assert mml_1.childNodes[1].childNodes[0].nodeValue == 'x' assert mml_1.childNodes[2].nodeName == 'cn' assert mml_1.childNodes[2].childNodes[0].nodeValue == '1' mml_2 = mp._print(Ne(1, x)) assert mml_2.nodeName == 'apply' assert mml_2.childNodes[0].nodeName == 'neq' assert mml_2.childNodes[1].nodeName == 'cn' assert mml_2.childNodes[1].childNodes[0].nodeValue == '1' assert mml_2.childNodes[2].nodeName == 'ci' assert mml_2.childNodes[2].childNodes[0].nodeValue == 'x' mml_3 = mp._print(Ge(1, x)) assert mml_3.nodeName == 'apply' assert mml_3.childNodes[0].nodeName == 'geq' assert mml_3.childNodes[1].nodeName == 'cn' assert mml_3.childNodes[1].childNodes[0].nodeValue == '1' assert mml_3.childNodes[2].nodeName == 'ci' assert mml_3.childNodes[2].childNodes[0].nodeValue == 'x' mml_4 = mp._print(Lt(1, x)) assert mml_4.nodeName == 'apply' assert mml_4.childNodes[0].nodeName == 'lt' assert mml_4.childNodes[1].nodeName == 'cn' assert mml_4.childNodes[1].childNodes[0].nodeValue == '1' assert mml_4.childNodes[2].nodeName == 'ci' assert mml_4.childNodes[2].childNodes[0].nodeValue == 'x' def test_content_symbol(): mml = mp._print(x) assert mml.nodeName == 'ci' assert mml.childNodes[0].nodeValue == 'x' del mml mml = mp._print(Symbol("x^2")) assert mml.nodeName == 'ci' assert mml.childNodes[0].nodeName == 'mml:msup' assert mml.childNodes[0].childNodes[0].nodeName == 'mml:mi' assert mml.childNodes[0].childNodes[0].childNodes[0].nodeValue == 'x' assert mml.childNodes[0].childNodes[1].nodeName == 'mml:mi' assert mml.childNodes[0].childNodes[1].childNodes[0].nodeValue == '2' del mml mml = mp._print(Symbol("x__2")) assert mml.nodeName == 'ci' assert mml.childNodes[0].nodeName == 'mml:msup' assert mml.childNodes[0].childNodes[0].nodeName == 'mml:mi' assert mml.childNodes[0].childNodes[0].childNodes[0].nodeValue == 'x' assert mml.childNodes[0].childNodes[1].nodeName == 'mml:mi' assert mml.childNodes[0].childNodes[1].childNodes[0].nodeValue == '2' del mml mml = mp._print(Symbol("x_2")) assert mml.nodeName == 'ci' assert mml.childNodes[0].nodeName == 'mml:msub' assert mml.childNodes[0].childNodes[0].nodeName == 'mml:mi' assert mml.childNodes[0].childNodes[0].childNodes[0].nodeValue == 'x' assert mml.childNodes[0].childNodes[1].nodeName == 'mml:mi' assert mml.childNodes[0].childNodes[1].childNodes[0].nodeValue == '2' del mml mml = mp._print(Symbol("x^3_2")) assert mml.nodeName == 'ci' assert mml.childNodes[0].nodeName == 'mml:msubsup' assert mml.childNodes[0].childNodes[0].nodeName == 'mml:mi' assert mml.childNodes[0].childNodes[0].childNodes[0].nodeValue == 'x' assert mml.childNodes[0].childNodes[1].nodeName == 'mml:mi' assert mml.childNodes[0].childNodes[1].childNodes[0].nodeValue == '2' assert mml.childNodes[0].childNodes[2].nodeName == 'mml:mi' assert mml.childNodes[0].childNodes[2].childNodes[0].nodeValue == '3' del mml mml = mp._print(Symbol("x__3_2")) assert mml.nodeName == 'ci' assert mml.childNodes[0].nodeName == 'mml:msubsup' assert mml.childNodes[0].childNodes[0].nodeName == 'mml:mi' assert mml.childNodes[0].childNodes[0].childNodes[0].nodeValue == 'x' assert mml.childNodes[0].childNodes[1].nodeName == 'mml:mi' assert mml.childNodes[0].childNodes[1].childNodes[0].nodeValue == '2' assert mml.childNodes[0].childNodes[2].nodeName == 'mml:mi' assert mml.childNodes[0].childNodes[2].childNodes[0].nodeValue == '3' del mml mml = mp._print(Symbol("x_2_a")) assert mml.nodeName == 'ci' assert mml.childNodes[0].nodeName == 'mml:msub' assert mml.childNodes[0].childNodes[0].nodeName == 'mml:mi' assert mml.childNodes[0].childNodes[0].childNodes[0].nodeValue == 'x' assert mml.childNodes[0].childNodes[1].nodeName == 'mml:mrow' assert mml.childNodes[0].childNodes[1].childNodes[0].nodeName == 'mml:mi' assert mml.childNodes[0].childNodes[1].childNodes[0].childNodes[ 0].nodeValue == '2' assert mml.childNodes[0].childNodes[1].childNodes[1].nodeName == 'mml:mo' assert mml.childNodes[0].childNodes[1].childNodes[1].childNodes[ 0].nodeValue == ' ' assert mml.childNodes[0].childNodes[1].childNodes[2].nodeName == 'mml:mi' assert mml.childNodes[0].childNodes[1].childNodes[2].childNodes[ 0].nodeValue == 'a' del mml mml = mp._print(Symbol("x^2^a")) assert mml.nodeName == 'ci' assert mml.childNodes[0].nodeName == 'mml:msup' assert mml.childNodes[0].childNodes[0].nodeName == 'mml:mi' assert mml.childNodes[0].childNodes[0].childNodes[0].nodeValue == 'x' assert mml.childNodes[0].childNodes[1].nodeName == 'mml:mrow' assert mml.childNodes[0].childNodes[1].childNodes[0].nodeName == 'mml:mi' assert mml.childNodes[0].childNodes[1].childNodes[0].childNodes[ 0].nodeValue == '2' assert mml.childNodes[0].childNodes[1].childNodes[1].nodeName == 'mml:mo' assert mml.childNodes[0].childNodes[1].childNodes[1].childNodes[ 0].nodeValue == ' ' assert mml.childNodes[0].childNodes[1].childNodes[2].nodeName == 'mml:mi' assert mml.childNodes[0].childNodes[1].childNodes[2].childNodes[ 0].nodeValue == 'a' del mml mml = mp._print(Symbol("x__2__a")) assert mml.nodeName == 'ci' assert mml.childNodes[0].nodeName == 'mml:msup' assert mml.childNodes[0].childNodes[0].nodeName == 'mml:mi' assert mml.childNodes[0].childNodes[0].childNodes[0].nodeValue == 'x' assert mml.childNodes[0].childNodes[1].nodeName == 'mml:mrow' assert mml.childNodes[0].childNodes[1].childNodes[0].nodeName == 'mml:mi' assert mml.childNodes[0].childNodes[1].childNodes[0].childNodes[ 0].nodeValue == '2' assert mml.childNodes[0].childNodes[1].childNodes[1].nodeName == 'mml:mo' assert mml.childNodes[0].childNodes[1].childNodes[1].childNodes[ 0].nodeValue == ' ' assert mml.childNodes[0].childNodes[1].childNodes[2].nodeName == 'mml:mi' assert mml.childNodes[0].childNodes[1].childNodes[2].childNodes[ 0].nodeValue == 'a' del mml def test_content_mathml_greek(): mml = mp._print(Symbol('alpha')) assert mml.nodeName == 'ci' assert mml.childNodes[0].nodeValue == '\N{GREEK SMALL LETTER ALPHA}' assert mp.doprint(Symbol('alpha')) == '<ci>&#945;</ci>' assert mp.doprint(Symbol('beta')) == '<ci>&#946;</ci>' assert mp.doprint(Symbol('gamma')) == '<ci>&#947;</ci>' assert mp.doprint(Symbol('delta')) == '<ci>&#948;</ci>' assert mp.doprint(Symbol('epsilon')) == '<ci>&#949;</ci>' assert mp.doprint(Symbol('zeta')) == '<ci>&#950;</ci>' assert mp.doprint(Symbol('eta')) == '<ci>&#951;</ci>' assert mp.doprint(Symbol('theta')) == '<ci>&#952;</ci>' assert mp.doprint(Symbol('iota')) == '<ci>&#953;</ci>' assert mp.doprint(Symbol('kappa')) == '<ci>&#954;</ci>' assert mp.doprint(Symbol('lambda')) == '<ci>&#955;</ci>' assert mp.doprint(Symbol('mu')) == '<ci>&#956;</ci>' assert mp.doprint(Symbol('nu')) == '<ci>&#957;</ci>' assert mp.doprint(Symbol('xi')) == '<ci>&#958;</ci>' assert mp.doprint(Symbol('omicron')) == '<ci>&#959;</ci>' assert mp.doprint(Symbol('pi')) == '<ci>&#960;</ci>' assert mp.doprint(Symbol('rho')) == '<ci>&#961;</ci>' assert mp.doprint(Symbol('varsigma')) == '<ci>&#962;</ci>' assert mp.doprint(Symbol('sigma')) == '<ci>&#963;</ci>' assert mp.doprint(Symbol('tau')) == '<ci>&#964;</ci>' assert mp.doprint(Symbol('upsilon')) == '<ci>&#965;</ci>' assert mp.doprint(Symbol('phi')) == '<ci>&#966;</ci>' assert mp.doprint(Symbol('chi')) == '<ci>&#967;</ci>' assert mp.doprint(Symbol('psi')) == '<ci>&#968;</ci>' assert mp.doprint(Symbol('omega')) == '<ci>&#969;</ci>' assert mp.doprint(Symbol('Alpha')) == '<ci>&#913;</ci>' assert mp.doprint(Symbol('Beta')) == '<ci>&#914;</ci>' assert mp.doprint(Symbol('Gamma')) == '<ci>&#915;</ci>' assert mp.doprint(Symbol('Delta')) == '<ci>&#916;</ci>' assert mp.doprint(Symbol('Epsilon')) == '<ci>&#917;</ci>' assert mp.doprint(Symbol('Zeta')) == '<ci>&#918;</ci>' assert mp.doprint(Symbol('Eta')) == '<ci>&#919;</ci>' assert mp.doprint(Symbol('Theta')) == '<ci>&#920;</ci>' assert mp.doprint(Symbol('Iota')) == '<ci>&#921;</ci>' assert mp.doprint(Symbol('Kappa')) == '<ci>&#922;</ci>' assert mp.doprint(Symbol('Lambda')) == '<ci>&#923;</ci>' assert mp.doprint(Symbol('Mu')) == '<ci>&#924;</ci>' assert mp.doprint(Symbol('Nu')) == '<ci>&#925;</ci>' assert mp.doprint(Symbol('Xi')) == '<ci>&#926;</ci>' assert mp.doprint(Symbol('Omicron')) == '<ci>&#927;</ci>' assert mp.doprint(Symbol('Pi')) == '<ci>&#928;</ci>' assert mp.doprint(Symbol('Rho')) == '<ci>&#929;</ci>' assert mp.doprint(Symbol('Sigma')) == '<ci>&#931;</ci>' assert mp.doprint(Symbol('Tau')) == '<ci>&#932;</ci>' assert mp.doprint(Symbol('Upsilon')) == '<ci>&#933;</ci>' assert mp.doprint(Symbol('Phi')) == '<ci>&#934;</ci>' assert mp.doprint(Symbol('Chi')) == '<ci>&#935;</ci>' assert mp.doprint(Symbol('Psi')) == '<ci>&#936;</ci>' assert mp.doprint(Symbol('Omega')) == '<ci>&#937;</ci>' def test_content_mathml_order(): expr = x**3 + x**2*y + 3*x*y**3 + y**4 mp = MathMLContentPrinter({'order': 'lex'}) mml = mp._print(expr) assert mml.childNodes[1].childNodes[0].nodeName == 'power' assert mml.childNodes[1].childNodes[1].childNodes[0].data == 'x' assert mml.childNodes[1].childNodes[2].childNodes[0].data == '3' assert mml.childNodes[4].childNodes[0].nodeName == 'power' assert mml.childNodes[4].childNodes[1].childNodes[0].data == 'y' assert mml.childNodes[4].childNodes[2].childNodes[0].data == '4' mp = MathMLContentPrinter({'order': 'rev-lex'}) mml = mp._print(expr) assert mml.childNodes[1].childNodes[0].nodeName == 'power' assert mml.childNodes[1].childNodes[1].childNodes[0].data == 'y' assert mml.childNodes[1].childNodes[2].childNodes[0].data == '4' assert mml.childNodes[4].childNodes[0].nodeName == 'power' assert mml.childNodes[4].childNodes[1].childNodes[0].data == 'x' assert mml.childNodes[4].childNodes[2].childNodes[0].data == '3' def test_content_settings(): raises(TypeError, lambda: mathml(x, method="garbage")) def test_content_mathml_logic(): assert mathml(And(x, y)) == '<apply><and/><ci>x</ci><ci>y</ci></apply>' assert mathml(Or(x, y)) == '<apply><or/><ci>x</ci><ci>y</ci></apply>' assert mathml(Xor(x, y)) == '<apply><xor/><ci>x</ci><ci>y</ci></apply>' assert mathml(Implies(x, y)) == '<apply><implies/><ci>x</ci><ci>y</ci></apply>' assert mathml(Not(x)) == '<apply><not/><ci>x</ci></apply>' def test_content_finite_sets(): assert mathml(FiniteSet(a)) == '<set><ci>a</ci></set>' assert mathml(FiniteSet(a, b)) == '<set><ci>a</ci><ci>b</ci></set>' assert mathml(FiniteSet(FiniteSet(a, b), c)) == \ '<set><ci>c</ci><set><ci>a</ci><ci>b</ci></set></set>' A = FiniteSet(a) B = FiniteSet(b) C = FiniteSet(c) D = FiniteSet(d) U1 = Union(A, B, evaluate=False) U2 = Union(C, D, evaluate=False) I1 = Intersection(A, B, evaluate=False) I2 = Intersection(C, D, evaluate=False) C1 = Complement(A, B, evaluate=False) C2 = Complement(C, D, evaluate=False) # XXX ProductSet does not support evaluate keyword P1 = ProductSet(A, B) P2 = ProductSet(C, D) assert mathml(U1) == \ '<apply><union/><set><ci>a</ci></set><set><ci>b</ci></set></apply>' assert mathml(I1) == \ '<apply><intersect/><set><ci>a</ci></set><set><ci>b</ci></set>' \ '</apply>' assert mathml(C1) == \ '<apply><setdiff/><set><ci>a</ci></set><set><ci>b</ci></set></apply>' assert mathml(P1) == \ '<apply><cartesianproduct/><set><ci>a</ci></set><set><ci>b</ci>' \ '</set></apply>' assert mathml(Intersection(A, U2, evaluate=False)) == \ '<apply><intersect/><set><ci>a</ci></set><apply><union/><set>' \ '<ci>c</ci></set><set><ci>d</ci></set></apply></apply>' assert mathml(Intersection(U1, U2, evaluate=False)) == \ '<apply><intersect/><apply><union/><set><ci>a</ci></set><set>' \ '<ci>b</ci></set></apply><apply><union/><set><ci>c</ci></set>' \ '<set><ci>d</ci></set></apply></apply>' # XXX Does the parenthesis appear correctly for these examples in mathjax? assert mathml(Intersection(C1, C2, evaluate=False)) == \ '<apply><intersect/><apply><setdiff/><set><ci>a</ci></set><set>' \ '<ci>b</ci></set></apply><apply><setdiff/><set><ci>c</ci></set>' \ '<set><ci>d</ci></set></apply></apply>' assert mathml(Intersection(P1, P2, evaluate=False)) == \ '<apply><intersect/><apply><cartesianproduct/><set><ci>a</ci></set>' \ '<set><ci>b</ci></set></apply><apply><cartesianproduct/><set>' \ '<ci>c</ci></set><set><ci>d</ci></set></apply></apply>' assert mathml(Union(A, I2, evaluate=False)) == \ '<apply><union/><set><ci>a</ci></set><apply><intersect/><set>' \ '<ci>c</ci></set><set><ci>d</ci></set></apply></apply>' assert mathml(Union(I1, I2, evaluate=False)) == \ '<apply><union/><apply><intersect/><set><ci>a</ci></set><set>' \ '<ci>b</ci></set></apply><apply><intersect/><set><ci>c</ci></set>' \ '<set><ci>d</ci></set></apply></apply>' assert mathml(Union(C1, C2, evaluate=False)) == \ '<apply><union/><apply><setdiff/><set><ci>a</ci></set><set>' \ '<ci>b</ci></set></apply><apply><setdiff/><set><ci>c</ci></set>' \ '<set><ci>d</ci></set></apply></apply>' assert mathml(Union(P1, P2, evaluate=False)) == \ '<apply><union/><apply><cartesianproduct/><set><ci>a</ci></set>' \ '<set><ci>b</ci></set></apply><apply><cartesianproduct/><set>' \ '<ci>c</ci></set><set><ci>d</ci></set></apply></apply>' assert mathml(Complement(A, C2, evaluate=False)) == \ '<apply><setdiff/><set><ci>a</ci></set><apply><setdiff/><set>' \ '<ci>c</ci></set><set><ci>d</ci></set></apply></apply>' assert mathml(Complement(U1, U2, evaluate=False)) == \ '<apply><setdiff/><apply><union/><set><ci>a</ci></set><set>' \ '<ci>b</ci></set></apply><apply><union/><set><ci>c</ci></set>' \ '<set><ci>d</ci></set></apply></apply>' assert mathml(Complement(I1, I2, evaluate=False)) == \ '<apply><setdiff/><apply><intersect/><set><ci>a</ci></set><set>' \ '<ci>b</ci></set></apply><apply><intersect/><set><ci>c</ci></set>' \ '<set><ci>d</ci></set></apply></apply>' assert mathml(Complement(P1, P2, evaluate=False)) == \ '<apply><setdiff/><apply><cartesianproduct/><set><ci>a</ci></set>' \ '<set><ci>b</ci></set></apply><apply><cartesianproduct/><set>' \ '<ci>c</ci></set><set><ci>d</ci></set></apply></apply>' assert mathml(ProductSet(A, P2)) == \ '<apply><cartesianproduct/><set><ci>a</ci></set>' \ '<apply><cartesianproduct/><set><ci>c</ci></set>' \ '<set><ci>d</ci></set></apply></apply>' assert mathml(ProductSet(U1, U2)) == \ '<apply><cartesianproduct/><apply><union/><set><ci>a</ci></set>' \ '<set><ci>b</ci></set></apply><apply><union/><set><ci>c</ci></set>' \ '<set><ci>d</ci></set></apply></apply>' assert mathml(ProductSet(I1, I2)) == \ '<apply><cartesianproduct/><apply><intersect/><set><ci>a</ci></set>' \ '<set><ci>b</ci></set></apply><apply><intersect/><set>' \ '<ci>c</ci></set><set><ci>d</ci></set></apply></apply>' assert mathml(ProductSet(C1, C2)) == \ '<apply><cartesianproduct/><apply><setdiff/><set><ci>a</ci></set>' \ '<set><ci>b</ci></set></apply><apply><setdiff/><set>' \ '<ci>c</ci></set><set><ci>d</ci></set></apply></apply>' def test_presentation_printmethod(): assert mpp.doprint(1 + x) == '<mrow><mi>x</mi><mo>+</mo><mn>1</mn></mrow>' assert mpp.doprint(x**2) == '<msup><mi>x</mi><mn>2</mn></msup>' assert mpp.doprint(x**-1) == '<mfrac><mn>1</mn><mi>x</mi></mfrac>' assert mpp.doprint(x**-2) == \ '<mfrac><mn>1</mn><msup><mi>x</mi><mn>2</mn></msup></mfrac>' assert mpp.doprint(2*x) == \ '<mrow><mn>2</mn><mo>&InvisibleTimes;</mo><mi>x</mi></mrow>' def test_presentation_mathml_core(): mml_1 = mpp._print(1 + x) assert mml_1.nodeName == 'mrow' nodes = mml_1.childNodes assert len(nodes) == 3 assert nodes[0].nodeName in ['mi', 'mn'] assert nodes[1].nodeName == 'mo' if nodes[0].nodeName == 'mn': assert nodes[0].childNodes[0].nodeValue == '1' assert nodes[2].childNodes[0].nodeValue == 'x' else: assert nodes[0].childNodes[0].nodeValue == 'x' assert nodes[2].childNodes[0].nodeValue == '1' mml_2 = mpp._print(x**2) assert mml_2.nodeName == 'msup' nodes = mml_2.childNodes assert nodes[0].childNodes[0].nodeValue == 'x' assert nodes[1].childNodes[0].nodeValue == '2' mml_3 = mpp._print(2*x) assert mml_3.nodeName == 'mrow' nodes = mml_3.childNodes assert nodes[0].childNodes[0].nodeValue == '2' assert nodes[1].childNodes[0].nodeValue == '&InvisibleTimes;' assert nodes[2].childNodes[0].nodeValue == 'x' mml = mpp._print(Float(1.0, 2)*x) assert mml.nodeName == 'mrow' nodes = mml.childNodes assert nodes[0].childNodes[0].nodeValue == '1.0' assert nodes[1].childNodes[0].nodeValue == '&InvisibleTimes;' assert nodes[2].childNodes[0].nodeValue == 'x' def test_presentation_mathml_functions(): mml_1 = mpp._print(sin(x)) assert mml_1.childNodes[0].childNodes[0 ].nodeValue == 'sin' assert mml_1.childNodes[1].childNodes[0 ].childNodes[0].nodeValue == 'x' mml_2 = mpp._print(diff(sin(x), x, evaluate=False)) assert mml_2.nodeName == 'mrow' assert mml_2.childNodes[0].childNodes[0 ].childNodes[0].childNodes[0].nodeValue == '&dd;' assert mml_2.childNodes[1].childNodes[1 ].nodeName == 'mfenced' assert mml_2.childNodes[0].childNodes[1 ].childNodes[0].childNodes[0].nodeValue == '&dd;' mml_3 = mpp._print(diff(cos(x*y), x, evaluate=False)) assert mml_3.childNodes[0].nodeName == 'mfrac' assert mml_3.childNodes[0].childNodes[0 ].childNodes[0].childNodes[0].nodeValue == '&#x2202;' assert mml_3.childNodes[1].childNodes[0 ].childNodes[0].nodeValue == 'cos' def test_print_derivative(): f = Function('f') d = Derivative(f(x, y, z), x, z, x, z, z, y) assert mathml(d) == \ '<apply><partialdiff/><bvar><ci>y</ci><ci>z</ci><degree><cn>2</cn></degree><ci>x</ci><ci>z</ci><ci>x</ci></bvar><apply><f/><ci>x</ci><ci>y</ci><ci>z</ci></apply></apply>' assert mathml(d, printer='presentation') == \ '<mrow><mfrac><mrow><msup><mo>&#x2202;</mo><mn>6</mn></msup></mrow><mrow><mo>&#x2202;</mo><mi>y</mi><msup><mo>&#x2202;</mo><mn>2</mn></msup><mi>z</mi><mo>&#x2202;</mo><mi>x</mi><mo>&#x2202;</mo><mi>z</mi><mo>&#x2202;</mo><mi>x</mi></mrow></mfrac><mrow><mi>f</mi><mfenced><mi>x</mi><mi>y</mi><mi>z</mi></mfenced></mrow></mrow>' def test_presentation_mathml_limits(): lim_fun = sin(x)/x mml_1 = mpp._print(Limit(lim_fun, x, 0)) assert mml_1.childNodes[0].nodeName == 'munder' assert mml_1.childNodes[0].childNodes[0 ].childNodes[0].nodeValue == 'lim' assert mml_1.childNodes[0].childNodes[1 ].childNodes[0].childNodes[0 ].nodeValue == 'x' assert mml_1.childNodes[0].childNodes[1 ].childNodes[1].childNodes[0 ].nodeValue == '&#x2192;' assert mml_1.childNodes[0].childNodes[1 ].childNodes[2].childNodes[0 ].nodeValue == '0' def test_presentation_mathml_integrals(): assert mpp.doprint(Integral(x, (x, 0, 1))) == \ '<mrow><msubsup><mo>&#x222B;</mo><mn>0</mn><mn>1</mn></msubsup>'\ '<mi>x</mi><mo>&dd;</mo><mi>x</mi></mrow>' assert mpp.doprint(Integral(log(x), x)) == \ '<mrow><mo>&#x222B;</mo><mrow><mi>log</mi><mfenced><mi>x</mi>'\ '</mfenced></mrow><mo>&dd;</mo><mi>x</mi></mrow>' assert mpp.doprint(Integral(x*y, x, y)) == \ '<mrow><mo>&#x222C;</mo><mrow><mi>x</mi><mo>&InvisibleTimes;</mo>'\ '<mi>y</mi></mrow><mo>&dd;</mo><mi>y</mi><mo>&dd;</mo><mi>x</mi></mrow>' z, w = symbols('z w') assert mpp.doprint(Integral(x*y*z, x, y, z)) == \ '<mrow><mo>&#x222D;</mo><mrow><mi>x</mi><mo>&InvisibleTimes;</mo>'\ '<mi>y</mi><mo>&InvisibleTimes;</mo><mi>z</mi></mrow><mo>&dd;</mo>'\ '<mi>z</mi><mo>&dd;</mo><mi>y</mi><mo>&dd;</mo><mi>x</mi></mrow>' assert mpp.doprint(Integral(x*y*z*w, x, y, z, w)) == \ '<mrow><mo>&#x222B;</mo><mo>&#x222B;</mo><mo>&#x222B;</mo>'\ '<mo>&#x222B;</mo><mrow><mi>w</mi><mo>&InvisibleTimes;</mo>'\ '<mi>x</mi><mo>&InvisibleTimes;</mo><mi>y</mi>'\ '<mo>&InvisibleTimes;</mo><mi>z</mi></mrow><mo>&dd;</mo><mi>w</mi>'\ '<mo>&dd;</mo><mi>z</mi><mo>&dd;</mo><mi>y</mi><mo>&dd;</mo><mi>x</mi></mrow>' assert mpp.doprint(Integral(x, x, y, (z, 0, 1))) == \ '<mrow><msubsup><mo>&#x222B;</mo><mn>0</mn><mn>1</mn></msubsup>'\ '<mo>&#x222B;</mo><mo>&#x222B;</mo><mi>x</mi><mo>&dd;</mo><mi>z</mi>'\ '<mo>&dd;</mo><mi>y</mi><mo>&dd;</mo><mi>x</mi></mrow>' assert mpp.doprint(Integral(x, (x, 0))) == \ '<mrow><msup><mo>&#x222B;</mo><mn>0</mn></msup><mi>x</mi><mo>&dd;</mo>'\ '<mi>x</mi></mrow>' def test_presentation_mathml_matrices(): A = Matrix([1, 2, 3]) B = Matrix([[0, 5, 4], [2, 3, 1], [9, 7, 9]]) mll_1 = mpp._print(A) assert mll_1.childNodes[0].nodeName == 'mtable' assert mll_1.childNodes[0].childNodes[0].nodeName == 'mtr' assert len(mll_1.childNodes[0].childNodes) == 3 assert mll_1.childNodes[0].childNodes[0].childNodes[0].nodeName == 'mtd' assert len(mll_1.childNodes[0].childNodes[0].childNodes) == 1 assert mll_1.childNodes[0].childNodes[0].childNodes[0 ].childNodes[0].childNodes[0].nodeValue == '1' assert mll_1.childNodes[0].childNodes[1].childNodes[0 ].childNodes[0].childNodes[0].nodeValue == '2' assert mll_1.childNodes[0].childNodes[2].childNodes[0 ].childNodes[0].childNodes[0].nodeValue == '3' mll_2 = mpp._print(B) assert mll_2.childNodes[0].nodeName == 'mtable' assert mll_2.childNodes[0].childNodes[0].nodeName == 'mtr' assert len(mll_2.childNodes[0].childNodes) == 3 assert mll_2.childNodes[0].childNodes[0].childNodes[0].nodeName == 'mtd' assert len(mll_2.childNodes[0].childNodes[0].childNodes) == 3 assert mll_2.childNodes[0].childNodes[0].childNodes[0 ].childNodes[0].childNodes[0].nodeValue == '0' assert mll_2.childNodes[0].childNodes[0].childNodes[1 ].childNodes[0].childNodes[0].nodeValue == '5' assert mll_2.childNodes[0].childNodes[0].childNodes[2 ].childNodes[0].childNodes[0].nodeValue == '4' assert mll_2.childNodes[0].childNodes[1].childNodes[0 ].childNodes[0].childNodes[0].nodeValue == '2' assert mll_2.childNodes[0].childNodes[1].childNodes[1 ].childNodes[0].childNodes[0].nodeValue == '3' assert mll_2.childNodes[0].childNodes[1].childNodes[2 ].childNodes[0].childNodes[0].nodeValue == '1' assert mll_2.childNodes[0].childNodes[2].childNodes[0 ].childNodes[0].childNodes[0].nodeValue == '9' assert mll_2.childNodes[0].childNodes[2].childNodes[1 ].childNodes[0].childNodes[0].nodeValue == '7' assert mll_2.childNodes[0].childNodes[2].childNodes[2 ].childNodes[0].childNodes[0].nodeValue == '9' def test_presentation_mathml_sums(): summand = x mml_1 = mpp._print(Sum(summand, (x, 1, 10))) assert mml_1.childNodes[0].nodeName == 'munderover' assert len(mml_1.childNodes[0].childNodes) == 3 assert mml_1.childNodes[0].childNodes[0].childNodes[0 ].nodeValue == '&#x2211;' assert len(mml_1.childNodes[0].childNodes[1].childNodes) == 3 assert mml_1.childNodes[0].childNodes[2].childNodes[0 ].nodeValue == '10' assert mml_1.childNodes[1].childNodes[0].nodeValue == 'x' def test_presentation_mathml_add(): mml = mpp._print(x**5 - x**4 + x) assert len(mml.childNodes) == 5 assert mml.childNodes[0].childNodes[0].childNodes[0 ].nodeValue == 'x' assert mml.childNodes[0].childNodes[1].childNodes[0 ].nodeValue == '5' assert mml.childNodes[1].childNodes[0].nodeValue == '-' assert mml.childNodes[2].childNodes[0].childNodes[0 ].nodeValue == 'x' assert mml.childNodes[2].childNodes[1].childNodes[0 ].nodeValue == '4' assert mml.childNodes[3].childNodes[0].nodeValue == '+' assert mml.childNodes[4].childNodes[0].nodeValue == 'x' def test_presentation_mathml_Rational(): mml_1 = mpp._print(Rational(1, 1)) assert mml_1.nodeName == 'mn' mml_2 = mpp._print(Rational(2, 5)) assert mml_2.nodeName == 'mfrac' assert mml_2.childNodes[0].childNodes[0].nodeValue == '2' assert mml_2.childNodes[1].childNodes[0].nodeValue == '5' def test_presentation_mathml_constants(): mml = mpp._print(I) assert mml.childNodes[0].nodeValue == '&ImaginaryI;' mml = mpp._print(E) assert mml.childNodes[0].nodeValue == '&ExponentialE;' mml = mpp._print(oo) assert mml.childNodes[0].nodeValue == '&#x221E;' mml = mpp._print(pi) assert mml.childNodes[0].nodeValue == '&pi;' assert mathml(GoldenRatio, printer='presentation') == '<mi>&#x3A6;</mi>' assert mathml(zoo, printer='presentation') == \ '<mover><mo>&#x221E;</mo><mo>~</mo></mover>' assert mathml(S.NaN, printer='presentation') == '<mi>NaN</mi>' def test_presentation_mathml_trig(): mml = mpp._print(sin(x)) assert mml.childNodes[0].childNodes[0].nodeValue == 'sin' mml = mpp._print(cos(x)) assert mml.childNodes[0].childNodes[0].nodeValue == 'cos' mml = mpp._print(tan(x)) assert mml.childNodes[0].childNodes[0].nodeValue == 'tan' mml = mpp._print(asin(x)) assert mml.childNodes[0].childNodes[0].nodeValue == 'arcsin' mml = mpp._print(acos(x)) assert mml.childNodes[0].childNodes[0].nodeValue == 'arccos' mml = mpp._print(atan(x)) assert mml.childNodes[0].childNodes[0].nodeValue == 'arctan' mml = mpp._print(sinh(x)) assert mml.childNodes[0].childNodes[0].nodeValue == 'sinh' mml = mpp._print(cosh(x)) assert mml.childNodes[0].childNodes[0].nodeValue == 'cosh' mml = mpp._print(tanh(x)) assert mml.childNodes[0].childNodes[0].nodeValue == 'tanh' mml = mpp._print(asinh(x)) assert mml.childNodes[0].childNodes[0].nodeValue == 'arcsinh' mml = mpp._print(atanh(x)) assert mml.childNodes[0].childNodes[0].nodeValue == 'arctanh' mml = mpp._print(acosh(x)) assert mml.childNodes[0].childNodes[0].nodeValue == 'arccosh' def test_presentation_mathml_relational(): mml_1 = mpp._print(Eq(x, 1)) assert len(mml_1.childNodes) == 3 assert mml_1.childNodes[0].nodeName == 'mi' assert mml_1.childNodes[0].childNodes[0].nodeValue == 'x' assert mml_1.childNodes[1].nodeName == 'mo' assert mml_1.childNodes[1].childNodes[0].nodeValue == '=' assert mml_1.childNodes[2].nodeName == 'mn' assert mml_1.childNodes[2].childNodes[0].nodeValue == '1' mml_2 = mpp._print(Ne(1, x)) assert len(mml_2.childNodes) == 3 assert mml_2.childNodes[0].nodeName == 'mn' assert mml_2.childNodes[0].childNodes[0].nodeValue == '1' assert mml_2.childNodes[1].nodeName == 'mo' assert mml_2.childNodes[1].childNodes[0].nodeValue == '&#x2260;' assert mml_2.childNodes[2].nodeName == 'mi' assert mml_2.childNodes[2].childNodes[0].nodeValue == 'x' mml_3 = mpp._print(Ge(1, x)) assert len(mml_3.childNodes) == 3 assert mml_3.childNodes[0].nodeName == 'mn' assert mml_3.childNodes[0].childNodes[0].nodeValue == '1' assert mml_3.childNodes[1].nodeName == 'mo' assert mml_3.childNodes[1].childNodes[0].nodeValue == '&#x2265;' assert mml_3.childNodes[2].nodeName == 'mi' assert mml_3.childNodes[2].childNodes[0].nodeValue == 'x' mml_4 = mpp._print(Lt(1, x)) assert len(mml_4.childNodes) == 3 assert mml_4.childNodes[0].nodeName == 'mn' assert mml_4.childNodes[0].childNodes[0].nodeValue == '1' assert mml_4.childNodes[1].nodeName == 'mo' assert mml_4.childNodes[1].childNodes[0].nodeValue == '<' assert mml_4.childNodes[2].nodeName == 'mi' assert mml_4.childNodes[2].childNodes[0].nodeValue == 'x' def test_presentation_symbol(): mml = mpp._print(x) assert mml.nodeName == 'mi' assert mml.childNodes[0].nodeValue == 'x' del mml mml = mpp._print(Symbol("x^2")) assert mml.nodeName == 'msup' assert mml.childNodes[0].nodeName == 'mi' assert mml.childNodes[0].childNodes[0].nodeValue == 'x' assert mml.childNodes[1].nodeName == 'mi' assert mml.childNodes[1].childNodes[0].nodeValue == '2' del mml mml = mpp._print(Symbol("x__2")) assert mml.nodeName == 'msup' assert mml.childNodes[0].nodeName == 'mi' assert mml.childNodes[0].childNodes[0].nodeValue == 'x' assert mml.childNodes[1].nodeName == 'mi' assert mml.childNodes[1].childNodes[0].nodeValue == '2' del mml mml = mpp._print(Symbol("x_2")) assert mml.nodeName == 'msub' assert mml.childNodes[0].nodeName == 'mi' assert mml.childNodes[0].childNodes[0].nodeValue == 'x' assert mml.childNodes[1].nodeName == 'mi' assert mml.childNodes[1].childNodes[0].nodeValue == '2' del mml mml = mpp._print(Symbol("x^3_2")) assert mml.nodeName == 'msubsup' assert mml.childNodes[0].nodeName == 'mi' assert mml.childNodes[0].childNodes[0].nodeValue == 'x' assert mml.childNodes[1].nodeName == 'mi' assert mml.childNodes[1].childNodes[0].nodeValue == '2' assert mml.childNodes[2].nodeName == 'mi' assert mml.childNodes[2].childNodes[0].nodeValue == '3' del mml mml = mpp._print(Symbol("x__3_2")) assert mml.nodeName == 'msubsup' assert mml.childNodes[0].nodeName == 'mi' assert mml.childNodes[0].childNodes[0].nodeValue == 'x' assert mml.childNodes[1].nodeName == 'mi' assert mml.childNodes[1].childNodes[0].nodeValue == '2' assert mml.childNodes[2].nodeName == 'mi' assert mml.childNodes[2].childNodes[0].nodeValue == '3' del mml mml = mpp._print(Symbol("x_2_a")) assert mml.nodeName == 'msub' assert mml.childNodes[0].nodeName == 'mi' assert mml.childNodes[0].childNodes[0].nodeValue == 'x' assert mml.childNodes[1].nodeName == 'mrow' assert mml.childNodes[1].childNodes[0].nodeName == 'mi' assert mml.childNodes[1].childNodes[0].childNodes[0].nodeValue == '2' assert mml.childNodes[1].childNodes[1].nodeName == 'mo' assert mml.childNodes[1].childNodes[1].childNodes[0].nodeValue == ' ' assert mml.childNodes[1].childNodes[2].nodeName == 'mi' assert mml.childNodes[1].childNodes[2].childNodes[0].nodeValue == 'a' del mml mml = mpp._print(Symbol("x^2^a")) assert mml.nodeName == 'msup' assert mml.childNodes[0].nodeName == 'mi' assert mml.childNodes[0].childNodes[0].nodeValue == 'x' assert mml.childNodes[1].nodeName == 'mrow' assert mml.childNodes[1].childNodes[0].nodeName == 'mi' assert mml.childNodes[1].childNodes[0].childNodes[0].nodeValue == '2' assert mml.childNodes[1].childNodes[1].nodeName == 'mo' assert mml.childNodes[1].childNodes[1].childNodes[0].nodeValue == ' ' assert mml.childNodes[1].childNodes[2].nodeName == 'mi' assert mml.childNodes[1].childNodes[2].childNodes[0].nodeValue == 'a' del mml mml = mpp._print(Symbol("x__2__a")) assert mml.nodeName == 'msup' assert mml.childNodes[0].nodeName == 'mi' assert mml.childNodes[0].childNodes[0].nodeValue == 'x' assert mml.childNodes[1].nodeName == 'mrow' assert mml.childNodes[1].childNodes[0].nodeName == 'mi' assert mml.childNodes[1].childNodes[0].childNodes[0].nodeValue == '2' assert mml.childNodes[1].childNodes[1].nodeName == 'mo' assert mml.childNodes[1].childNodes[1].childNodes[0].nodeValue == ' ' assert mml.childNodes[1].childNodes[2].nodeName == 'mi' assert mml.childNodes[1].childNodes[2].childNodes[0].nodeValue == 'a' del mml def test_presentation_mathml_greek(): mml = mpp._print(Symbol('alpha')) assert mml.nodeName == 'mi' assert mml.childNodes[0].nodeValue == '\N{GREEK SMALL LETTER ALPHA}' assert mpp.doprint(Symbol('alpha')) == '<mi>&#945;</mi>' assert mpp.doprint(Symbol('beta')) == '<mi>&#946;</mi>' assert mpp.doprint(Symbol('gamma')) == '<mi>&#947;</mi>' assert mpp.doprint(Symbol('delta')) == '<mi>&#948;</mi>' assert mpp.doprint(Symbol('epsilon')) == '<mi>&#949;</mi>' assert mpp.doprint(Symbol('zeta')) == '<mi>&#950;</mi>' assert mpp.doprint(Symbol('eta')) == '<mi>&#951;</mi>' assert mpp.doprint(Symbol('theta')) == '<mi>&#952;</mi>' assert mpp.doprint(Symbol('iota')) == '<mi>&#953;</mi>' assert mpp.doprint(Symbol('kappa')) == '<mi>&#954;</mi>' assert mpp.doprint(Symbol('lambda')) == '<mi>&#955;</mi>' assert mpp.doprint(Symbol('mu')) == '<mi>&#956;</mi>' assert mpp.doprint(Symbol('nu')) == '<mi>&#957;</mi>' assert mpp.doprint(Symbol('xi')) == '<mi>&#958;</mi>' assert mpp.doprint(Symbol('omicron')) == '<mi>&#959;</mi>' assert mpp.doprint(Symbol('pi')) == '<mi>&#960;</mi>' assert mpp.doprint(Symbol('rho')) == '<mi>&#961;</mi>' assert mpp.doprint(Symbol('varsigma')) == '<mi>&#962;</mi>' assert mpp.doprint(Symbol('sigma')) == '<mi>&#963;</mi>' assert mpp.doprint(Symbol('tau')) == '<mi>&#964;</mi>' assert mpp.doprint(Symbol('upsilon')) == '<mi>&#965;</mi>' assert mpp.doprint(Symbol('phi')) == '<mi>&#966;</mi>' assert mpp.doprint(Symbol('chi')) == '<mi>&#967;</mi>' assert mpp.doprint(Symbol('psi')) == '<mi>&#968;</mi>' assert mpp.doprint(Symbol('omega')) == '<mi>&#969;</mi>' assert mpp.doprint(Symbol('Alpha')) == '<mi>&#913;</mi>' assert mpp.doprint(Symbol('Beta')) == '<mi>&#914;</mi>' assert mpp.doprint(Symbol('Gamma')) == '<mi>&#915;</mi>' assert mpp.doprint(Symbol('Delta')) == '<mi>&#916;</mi>' assert mpp.doprint(Symbol('Epsilon')) == '<mi>&#917;</mi>' assert mpp.doprint(Symbol('Zeta')) == '<mi>&#918;</mi>' assert mpp.doprint(Symbol('Eta')) == '<mi>&#919;</mi>' assert mpp.doprint(Symbol('Theta')) == '<mi>&#920;</mi>' assert mpp.doprint(Symbol('Iota')) == '<mi>&#921;</mi>' assert mpp.doprint(Symbol('Kappa')) == '<mi>&#922;</mi>' assert mpp.doprint(Symbol('Lambda')) == '<mi>&#923;</mi>' assert mpp.doprint(Symbol('Mu')) == '<mi>&#924;</mi>' assert mpp.doprint(Symbol('Nu')) == '<mi>&#925;</mi>' assert mpp.doprint(Symbol('Xi')) == '<mi>&#926;</mi>' assert mpp.doprint(Symbol('Omicron')) == '<mi>&#927;</mi>' assert mpp.doprint(Symbol('Pi')) == '<mi>&#928;</mi>' assert mpp.doprint(Symbol('Rho')) == '<mi>&#929;</mi>' assert mpp.doprint(Symbol('Sigma')) == '<mi>&#931;</mi>' assert mpp.doprint(Symbol('Tau')) == '<mi>&#932;</mi>' assert mpp.doprint(Symbol('Upsilon')) == '<mi>&#933;</mi>' assert mpp.doprint(Symbol('Phi')) == '<mi>&#934;</mi>' assert mpp.doprint(Symbol('Chi')) == '<mi>&#935;</mi>' assert mpp.doprint(Symbol('Psi')) == '<mi>&#936;</mi>' assert mpp.doprint(Symbol('Omega')) == '<mi>&#937;</mi>' def test_presentation_mathml_order(): expr = x**3 + x**2*y + 3*x*y**3 + y**4 mp = MathMLPresentationPrinter({'order': 'lex'}) mml = mp._print(expr) assert mml.childNodes[0].nodeName == 'msup' assert mml.childNodes[0].childNodes[0].childNodes[0].nodeValue == 'x' assert mml.childNodes[0].childNodes[1].childNodes[0].nodeValue == '3' assert mml.childNodes[6].nodeName == 'msup' assert mml.childNodes[6].childNodes[0].childNodes[0].nodeValue == 'y' assert mml.childNodes[6].childNodes[1].childNodes[0].nodeValue == '4' mp = MathMLPresentationPrinter({'order': 'rev-lex'}) mml = mp._print(expr) assert mml.childNodes[0].nodeName == 'msup' assert mml.childNodes[0].childNodes[0].childNodes[0].nodeValue == 'y' assert mml.childNodes[0].childNodes[1].childNodes[0].nodeValue == '4' assert mml.childNodes[6].nodeName == 'msup' assert mml.childNodes[6].childNodes[0].childNodes[0].nodeValue == 'x' assert mml.childNodes[6].childNodes[1].childNodes[0].nodeValue == '3' def test_print_intervals(): a = Symbol('a', real=True) assert mpp.doprint(Interval(0, a)) == \ '<mrow><mfenced close="]" open="["><mn>0</mn><mi>a</mi></mfenced></mrow>' assert mpp.doprint(Interval(0, a, False, False)) == \ '<mrow><mfenced close="]" open="["><mn>0</mn><mi>a</mi></mfenced></mrow>' assert mpp.doprint(Interval(0, a, True, False)) == \ '<mrow><mfenced close="]" open="("><mn>0</mn><mi>a</mi></mfenced></mrow>' assert mpp.doprint(Interval(0, a, False, True)) == \ '<mrow><mfenced close=")" open="["><mn>0</mn><mi>a</mi></mfenced></mrow>' assert mpp.doprint(Interval(0, a, True, True)) == \ '<mrow><mfenced close=")" open="("><mn>0</mn><mi>a</mi></mfenced></mrow>' def test_print_tuples(): assert mpp.doprint(Tuple(0,)) == \ '<mrow><mfenced><mn>0</mn></mfenced></mrow>' assert mpp.doprint(Tuple(0, a)) == \ '<mrow><mfenced><mn>0</mn><mi>a</mi></mfenced></mrow>' assert mpp.doprint(Tuple(0, a, a)) == \ '<mrow><mfenced><mn>0</mn><mi>a</mi><mi>a</mi></mfenced></mrow>' assert mpp.doprint(Tuple(0, 1, 2, 3, 4)) == \ '<mrow><mfenced><mn>0</mn><mn>1</mn><mn>2</mn><mn>3</mn><mn>4</mn></mfenced></mrow>' assert mpp.doprint(Tuple(0, 1, Tuple(2, 3, 4))) == \ '<mrow><mfenced><mn>0</mn><mn>1</mn><mrow><mfenced><mn>2</mn><mn>3'\ '</mn><mn>4</mn></mfenced></mrow></mfenced></mrow>' def test_print_re_im(): assert mpp.doprint(re(x)) == \ '<mrow><mi mathvariant="fraktur">R</mi><mfenced><mi>x</mi></mfenced></mrow>' assert mpp.doprint(im(x)) == \ '<mrow><mi mathvariant="fraktur">I</mi><mfenced><mi>x</mi></mfenced></mrow>' assert mpp.doprint(re(x + 1)) == \ '<mrow><mrow><mi mathvariant="fraktur">R</mi><mfenced><mi>x</mi>'\ '</mfenced></mrow><mo>+</mo><mn>1</mn></mrow>' assert mpp.doprint(im(x + 1)) == \ '<mrow><mi mathvariant="fraktur">I</mi><mfenced><mi>x</mi></mfenced></mrow>' def test_print_Abs(): assert mpp.doprint(Abs(x)) == \ '<mrow><mfenced close="|" open="|"><mi>x</mi></mfenced></mrow>' assert mpp.doprint(Abs(x + 1)) == \ '<mrow><mfenced close="|" open="|"><mrow><mi>x</mi><mo>+</mo><mn>1</mn></mrow></mfenced></mrow>' def test_print_Determinant(): assert mpp.doprint(Determinant(Matrix([[1, 2], [3, 4]]))) == \ '<mrow><mfenced close="|" open="|"><mfenced close="]" open="["><mtable><mtr><mtd><mn>1</mn></mtd><mtd><mn>2</mn></mtd></mtr><mtr><mtd><mn>3</mn></mtd><mtd><mn>4</mn></mtd></mtr></mtable></mfenced></mfenced></mrow>' def test_presentation_settings(): raises(TypeError, lambda: mathml(x, printer='presentation', method="garbage")) def test_toprettyxml_hooking(): # test that the patch doesn't influence the behavior of the standard # library import xml.dom.minidom doc1 = xml.dom.minidom.parseString( "<apply><plus/><ci>x</ci><cn>1</cn></apply>") doc2 = xml.dom.minidom.parseString( "<mrow><mi>x</mi><mo>+</mo><mn>1</mn></mrow>") prettyxml_old1 = doc1.toprettyxml() prettyxml_old2 = doc2.toprettyxml() mp.apply_patch() mp.restore_patch() assert prettyxml_old1 == doc1.toprettyxml() assert prettyxml_old2 == doc2.toprettyxml() def test_print_domains(): from sympy import Complexes, Integers, Naturals, Naturals0, Reals assert mpp.doprint(Complexes) == '<mi mathvariant="normal">&#x2102;</mi>' assert mpp.doprint(Integers) == '<mi mathvariant="normal">&#x2124;</mi>' assert mpp.doprint(Naturals) == '<mi mathvariant="normal">&#x2115;</mi>' assert mpp.doprint(Naturals0) == \ '<msub><mi mathvariant="normal">&#x2115;</mi><mn>0</mn></msub>' assert mpp.doprint(Reals) == '<mi mathvariant="normal">&#x211D;</mi>' def test_print_expression_with_minus(): assert mpp.doprint(-x) == '<mrow><mo>-</mo><mi>x</mi></mrow>' assert mpp.doprint(-x/y) == \ '<mrow><mo>-</mo><mfrac><mi>x</mi><mi>y</mi></mfrac></mrow>' assert mpp.doprint(-Rational(1, 2)) == \ '<mrow><mo>-</mo><mfrac><mn>1</mn><mn>2</mn></mfrac></mrow>' def test_print_AssocOp(): from sympy.core.operations import AssocOp class TestAssocOp(AssocOp): identity = 0 expr = TestAssocOp(1, 2) mpp.doprint(expr) == \ '<mrow><mi>testassocop</mi><mn>2</mn><mn>1</mn></mrow>' def test_print_basic(): expr = Basic(1, 2) assert mpp.doprint(expr) == \ '<mrow><mi>basic</mi><mfenced><mn>1</mn><mn>2</mn></mfenced></mrow>' assert mp.doprint(expr) == '<basic><cn>1</cn><cn>2</cn></basic>' def test_mat_delim_print(): expr = Matrix([[1, 2], [3, 4]]) assert mathml(expr, printer='presentation', mat_delim='[') == \ '<mfenced close="]" open="["><mtable><mtr><mtd><mn>1</mn></mtd><mtd>'\ '<mn>2</mn></mtd></mtr><mtr><mtd><mn>3</mn></mtd><mtd><mn>4</mn>'\ '</mtd></mtr></mtable></mfenced>' assert mathml(expr, printer='presentation', mat_delim='(') == \ '<mfenced><mtable><mtr><mtd><mn>1</mn></mtd><mtd><mn>2</mn></mtd>'\ '</mtr><mtr><mtd><mn>3</mn></mtd><mtd><mn>4</mn></mtd></mtr></mtable></mfenced>' assert mathml(expr, printer='presentation', mat_delim='') == \ '<mtable><mtr><mtd><mn>1</mn></mtd><mtd><mn>2</mn></mtd></mtr><mtr>'\ '<mtd><mn>3</mn></mtd><mtd><mn>4</mn></mtd></mtr></mtable>' def test_ln_notation_print(): expr = log(x) assert mathml(expr, printer='presentation') == \ '<mrow><mi>log</mi><mfenced><mi>x</mi></mfenced></mrow>' assert mathml(expr, printer='presentation', ln_notation=False) == \ '<mrow><mi>log</mi><mfenced><mi>x</mi></mfenced></mrow>' assert mathml(expr, printer='presentation', ln_notation=True) == \ '<mrow><mi>ln</mi><mfenced><mi>x</mi></mfenced></mrow>' def test_mul_symbol_print(): expr = x * y assert mathml(expr, printer='presentation') == \ '<mrow><mi>x</mi><mo>&InvisibleTimes;</mo><mi>y</mi></mrow>' assert mathml(expr, printer='presentation', mul_symbol=None) == \ '<mrow><mi>x</mi><mo>&InvisibleTimes;</mo><mi>y</mi></mrow>' assert mathml(expr, printer='presentation', mul_symbol='dot') == \ '<mrow><mi>x</mi><mo>&#xB7;</mo><mi>y</mi></mrow>' assert mathml(expr, printer='presentation', mul_symbol='ldot') == \ '<mrow><mi>x</mi><mo>&#x2024;</mo><mi>y</mi></mrow>' assert mathml(expr, printer='presentation', mul_symbol='times') == \ '<mrow><mi>x</mi><mo>&#xD7;</mo><mi>y</mi></mrow>' def test_print_lerchphi(): assert mpp.doprint(lerchphi(1, 2, 3)) == \ '<mrow><mi>&#x3A6;</mi><mfenced><mn>1</mn><mn>2</mn><mn>3</mn></mfenced></mrow>' def test_print_polylog(): assert mp.doprint(polylog(x, y)) == \ '<apply><polylog/><ci>x</ci><ci>y</ci></apply>' assert mpp.doprint(polylog(x, y)) == \ '<mrow><msub><mi>Li</mi><mi>x</mi></msub><mfenced><mi>y</mi></mfenced></mrow>' def test_print_set_frozenset(): f = frozenset({1, 5, 3}) assert mpp.doprint(f) == \ '<mfenced close="}" open="{"><mn>1</mn><mn>3</mn><mn>5</mn></mfenced>' s = set({1, 2, 3}) assert mpp.doprint(s) == \ '<mfenced close="}" open="{"><mn>1</mn><mn>2</mn><mn>3</mn></mfenced>' def test_print_FiniteSet(): f1 = FiniteSet(x, 1, 3) assert mpp.doprint(f1) == \ '<mfenced close="}" open="{"><mn>1</mn><mn>3</mn><mi>x</mi></mfenced>' def test_print_LambertW(): assert mpp.doprint(LambertW(x)) == '<mrow><mi>W</mi><mfenced><mi>x</mi></mfenced></mrow>' assert mpp.doprint(LambertW(x, y)) == '<mrow><mi>W</mi><mfenced><mi>x</mi><mi>y</mi></mfenced></mrow>' def test_print_EmptySet(): assert mpp.doprint(EmptySet()) == '<mo>&#x2205;</mo>' def test_print_UniversalSet(): assert mpp.doprint(S.UniversalSet) == '<mo>&#x1D54C;</mo>' def test_print_spaces(): assert mpp.doprint(HilbertSpace()) == '<mi>&#x210B;</mi>' assert mpp.doprint(ComplexSpace(2)) == '<msup>&#x1D49E;<mn>2</mn></msup>' assert mpp.doprint(FockSpace()) == '<mi>&#x2131;</mi>' def test_print_constants(): assert mpp.doprint(hbar) == '<mi>&#x210F;</mi>' assert mpp.doprint(TribonacciConstant) == '<mi>TribonacciConstant</mi>' assert mpp.doprint(EulerGamma) == '<mi>&#x3B3;</mi>' def test_print_Contains(): assert mpp.doprint(Contains(x, S.Naturals)) == \ '<mrow><mi>x</mi><mo>&#x2208;</mo><mi mathvariant="normal">&#x2115;</mi></mrow>' def test_print_Dagger(): assert mpp.doprint(Dagger(x)) == '<msup><mi>x</mi>&#x2020;</msup>' def test_print_SetOp(): f1 = FiniteSet(x, 1, 3) f2 = FiniteSet(y, 2, 4) prntr = lambda x: mathml(x, printer='presentation') assert prntr(Union(f1, f2, evaluate=False)) == \ '<mrow><mfenced close="}" open="{"><mn>1</mn><mn>3</mn><mi>x</mi>'\ '</mfenced><mo>&#x222A;</mo><mfenced close="}" open="{"><mn>2</mn>'\ '<mn>4</mn><mi>y</mi></mfenced></mrow>' assert prntr(Intersection(f1, f2, evaluate=False)) == \ '<mrow><mfenced close="}" open="{"><mn>1</mn><mn>3</mn><mi>x</mi>'\ '</mfenced><mo>&#x2229;</mo><mfenced close="}" open="{"><mn>2</mn>'\ '<mn>4</mn><mi>y</mi></mfenced></mrow>' assert prntr(Complement(f1, f2, evaluate=False)) == \ '<mrow><mfenced close="}" open="{"><mn>1</mn><mn>3</mn><mi>x</mi>'\ '</mfenced><mo>&#x2216;</mo><mfenced close="}" open="{"><mn>2</mn>'\ '<mn>4</mn><mi>y</mi></mfenced></mrow>' assert prntr(SymmetricDifference(f1, f2, evaluate=False)) == \ '<mrow><mfenced close="}" open="{"><mn>1</mn><mn>3</mn><mi>x</mi>'\ '</mfenced><mo>&#x2206;</mo><mfenced close="}" open="{"><mn>2</mn>'\ '<mn>4</mn><mi>y</mi></mfenced></mrow>' A = FiniteSet(a) C = FiniteSet(c) D = FiniteSet(d) U1 = Union(C, D, evaluate=False) I1 = Intersection(C, D, evaluate=False) C1 = Complement(C, D, evaluate=False) D1 = SymmetricDifference(C, D, evaluate=False) # XXX ProductSet does not support evaluate keyword P1 = ProductSet(C, D) assert prntr(Union(A, I1, evaluate=False)) == \ '<mrow><mfenced close="}" open="{"><mi>a</mi></mfenced>' \ '<mo>&#x222A;</mo><mfenced><mrow><mfenced close="}" open="{">' \ '<mi>c</mi></mfenced><mo>&#x2229;</mo><mfenced close="}" open="{">' \ '<mi>d</mi></mfenced></mrow></mfenced></mrow>' assert prntr(Intersection(A, C1, evaluate=False)) == \ '<mrow><mfenced close="}" open="{"><mi>a</mi></mfenced>' \ '<mo>&#x2229;</mo><mfenced><mrow><mfenced close="}" open="{">' \ '<mi>c</mi></mfenced><mo>&#x2216;</mo><mfenced close="}" open="{">' \ '<mi>d</mi></mfenced></mrow></mfenced></mrow>' assert prntr(Complement(A, D1, evaluate=False)) == \ '<mrow><mfenced close="}" open="{"><mi>a</mi></mfenced>' \ '<mo>&#x2216;</mo><mfenced><mrow><mfenced close="}" open="{">' \ '<mi>c</mi></mfenced><mo>&#x2206;</mo><mfenced close="}" open="{">' \ '<mi>d</mi></mfenced></mrow></mfenced></mrow>' assert prntr(SymmetricDifference(A, P1, evaluate=False)) == \ '<mrow><mfenced close="}" open="{"><mi>a</mi></mfenced>' \ '<mo>&#x2206;</mo><mfenced><mrow><mfenced close="}" open="{">' \ '<mi>c</mi></mfenced><mo>&#x00d7;</mo><mfenced close="}" open="{">' \ '<mi>d</mi></mfenced></mrow></mfenced></mrow>' assert prntr(ProductSet(A, U1)) == \ '<mrow><mfenced close="}" open="{"><mi>a</mi></mfenced>' \ '<mo>&#x00d7;</mo><mfenced><mrow><mfenced close="}" open="{">' \ '<mi>c</mi></mfenced><mo>&#x222A;</mo><mfenced close="}" open="{">' \ '<mi>d</mi></mfenced></mrow></mfenced></mrow>' def test_print_logic(): assert mpp.doprint(And(x, y)) == \ '<mrow><mi>x</mi><mo>&#x2227;</mo><mi>y</mi></mrow>' assert mpp.doprint(Or(x, y)) == \ '<mrow><mi>x</mi><mo>&#x2228;</mo><mi>y</mi></mrow>' assert mpp.doprint(Xor(x, y)) == \ '<mrow><mi>x</mi><mo>&#x22BB;</mo><mi>y</mi></mrow>' assert mpp.doprint(Implies(x, y)) == \ '<mrow><mi>x</mi><mo>&#x21D2;</mo><mi>y</mi></mrow>' assert mpp.doprint(Equivalent(x, y)) == \ '<mrow><mi>x</mi><mo>&#x21D4;</mo><mi>y</mi></mrow>' assert mpp.doprint(And(Eq(x, y), x > 4)) == \ '<mrow><mrow><mi>x</mi><mo>=</mo><mi>y</mi></mrow><mo>&#x2227;</mo>'\ '<mrow><mi>x</mi><mo>></mo><mn>4</mn></mrow></mrow>' assert mpp.doprint(And(Eq(x, 3), y < 3, x > y + 1)) == \ '<mrow><mrow><mi>x</mi><mo>=</mo><mn>3</mn></mrow><mo>&#x2227;</mo>'\ '<mrow><mi>x</mi><mo>></mo><mrow><mi>y</mi><mo>+</mo><mn>1</mn></mrow>'\ '</mrow><mo>&#x2227;</mo><mrow><mi>y</mi><mo><</mo><mn>3</mn></mrow></mrow>' assert mpp.doprint(Or(Eq(x, y), x > 4)) == \ '<mrow><mrow><mi>x</mi><mo>=</mo><mi>y</mi></mrow><mo>&#x2228;</mo>'\ '<mrow><mi>x</mi><mo>></mo><mn>4</mn></mrow></mrow>' assert mpp.doprint(And(Eq(x, 3), Or(y < 3, x > y + 1))) == \ '<mrow><mrow><mi>x</mi><mo>=</mo><mn>3</mn></mrow><mo>&#x2227;</mo>'\ '<mfenced><mrow><mrow><mi>x</mi><mo>></mo><mrow><mi>y</mi><mo>+</mo>'\ '<mn>1</mn></mrow></mrow><mo>&#x2228;</mo><mrow><mi>y</mi><mo><</mo>'\ '<mn>3</mn></mrow></mrow></mfenced></mrow>' assert mpp.doprint(Not(x)) == '<mrow><mo>&#xAC;</mo><mi>x</mi></mrow>' assert mpp.doprint(Not(And(x, y))) == \ '<mrow><mo>&#xAC;</mo><mfenced><mrow><mi>x</mi><mo>&#x2227;</mo>'\ '<mi>y</mi></mrow></mfenced></mrow>' def test_root_notation_print(): assert mathml(x**(S.One/3), printer='presentation') == \ '<mroot><mi>x</mi><mn>3</mn></mroot>' assert mathml(x**(S.One/3), printer='presentation', root_notation=False) ==\ '<msup><mi>x</mi><mfrac><mn>1</mn><mn>3</mn></mfrac></msup>' assert mathml(x**(S.One/3), printer='content') == \ '<apply><root/><degree><cn>3</cn></degree><ci>x</ci></apply>' assert mathml(x**(S.One/3), printer='content', root_notation=False) == \ '<apply><power/><ci>x</ci><apply><divide/><cn>1</cn><cn>3</cn></apply></apply>' assert mathml(x**(Rational(-1, 3)), printer='presentation') == \ '<mfrac><mn>1</mn><mroot><mi>x</mi><mn>3</mn></mroot></mfrac>' assert mathml(x**(Rational(-1, 3)), printer='presentation', root_notation=False) \ == '<mfrac><mn>1</mn><msup><mi>x</mi><mfrac><mn>1</mn><mn>3</mn></mfrac></msup></mfrac>' def test_fold_frac_powers_print(): expr = x ** Rational(5, 2) assert mathml(expr, printer='presentation') == \ '<msup><mi>x</mi><mfrac><mn>5</mn><mn>2</mn></mfrac></msup>' assert mathml(expr, printer='presentation', fold_frac_powers=True) == \ '<msup><mi>x</mi><mfrac bevelled="true"><mn>5</mn><mn>2</mn></mfrac></msup>' assert mathml(expr, printer='presentation', fold_frac_powers=False) == \ '<msup><mi>x</mi><mfrac><mn>5</mn><mn>2</mn></mfrac></msup>' def test_fold_short_frac_print(): expr = Rational(2, 5) assert mathml(expr, printer='presentation') == \ '<mfrac><mn>2</mn><mn>5</mn></mfrac>' assert mathml(expr, printer='presentation', fold_short_frac=True) == \ '<mfrac bevelled="true"><mn>2</mn><mn>5</mn></mfrac>' assert mathml(expr, printer='presentation', fold_short_frac=False) == \ '<mfrac><mn>2</mn><mn>5</mn></mfrac>' def test_print_factorials(): assert mpp.doprint(factorial(x)) == '<mrow><mi>x</mi><mo>!</mo></mrow>' assert mpp.doprint(factorial(x + 1)) == \ '<mrow><mfenced><mrow><mi>x</mi><mo>+</mo><mn>1</mn></mrow></mfenced><mo>!</mo></mrow>' assert mpp.doprint(factorial2(x)) == '<mrow><mi>x</mi><mo>!!</mo></mrow>' assert mpp.doprint(factorial2(x + 1)) == \ '<mrow><mfenced><mrow><mi>x</mi><mo>+</mo><mn>1</mn></mrow></mfenced><mo>!!</mo></mrow>' assert mpp.doprint(binomial(x, y)) == \ '<mfenced><mfrac linethickness="0"><mi>x</mi><mi>y</mi></mfrac></mfenced>' assert mpp.doprint(binomial(4, x + y)) == \ '<mfenced><mfrac linethickness="0"><mn>4</mn><mrow><mi>x</mi>'\ '<mo>+</mo><mi>y</mi></mrow></mfrac></mfenced>' def test_print_floor(): expr = floor(x) assert mathml(expr, printer='presentation') == \ '<mrow><mfenced close="&#8971;" open="&#8970;"><mi>x</mi></mfenced></mrow>' def test_print_ceiling(): expr = ceiling(x) assert mathml(expr, printer='presentation') == \ '<mrow><mfenced close="&#8969;" open="&#8968;"><mi>x</mi></mfenced></mrow>' def test_print_Lambda(): expr = Lambda(x, x+1) assert mathml(expr, printer='presentation') == \ '<mfenced><mrow><mi>x</mi><mo>&#x21A6;</mo><mrow><mi>x</mi><mo>+</mo>'\ '<mn>1</mn></mrow></mrow></mfenced>' expr = Lambda((x, y), x + y) assert mathml(expr, printer='presentation') == \ '<mfenced><mrow><mrow><mfenced><mi>x</mi><mi>y</mi></mfenced></mrow>'\ '<mo>&#x21A6;</mo><mrow><mi>x</mi><mo>+</mo><mi>y</mi></mrow></mrow></mfenced>' def test_print_conjugate(): assert mpp.doprint(conjugate(x)) == \ '<menclose notation="top"><mi>x</mi></menclose>' assert mpp.doprint(conjugate(x + 1)) == \ '<mrow><menclose notation="top"><mi>x</mi></menclose><mo>+</mo><mn>1</mn></mrow>' def test_print_AccumBounds(): a = Symbol('a', real=True) assert mpp.doprint(AccumBounds(0, 1)) == '<mfenced close="&#10217;" open="&#10216;"><mn>0</mn><mn>1</mn></mfenced>' assert mpp.doprint(AccumBounds(0, a)) == '<mfenced close="&#10217;" open="&#10216;"><mn>0</mn><mi>a</mi></mfenced>' assert mpp.doprint(AccumBounds(a + 1, a + 2)) == '<mfenced close="&#10217;" open="&#10216;"><mrow><mi>a</mi><mo>+</mo><mn>1</mn></mrow><mrow><mi>a</mi><mo>+</mo><mn>2</mn></mrow></mfenced>' def test_print_Float(): assert mpp.doprint(Float(1e100)) == '<mrow><mn>1.0</mn><mo>&#xB7;</mo><msup><mn>10</mn><mn>100</mn></msup></mrow>' assert mpp.doprint(Float(1e-100)) == '<mrow><mn>1.0</mn><mo>&#xB7;</mo><msup><mn>10</mn><mn>-100</mn></msup></mrow>' assert mpp.doprint(Float(-1e100)) == '<mrow><mn>-1.0</mn><mo>&#xB7;</mo><msup><mn>10</mn><mn>100</mn></msup></mrow>' assert mpp.doprint(Float(1.0*oo)) == '<mi>&#x221E;</mi>' assert mpp.doprint(Float(-1.0*oo)) == '<mrow><mo>-</mo><mi>&#x221E;</mi></mrow>' def test_print_different_functions(): assert mpp.doprint(gamma(x)) == '<mrow><mi>&#x393;</mi><mfenced><mi>x</mi></mfenced></mrow>' assert mpp.doprint(lowergamma(x, y)) == '<mrow><mi>&#x3B3;</mi><mfenced><mi>x</mi><mi>y</mi></mfenced></mrow>' assert mpp.doprint(uppergamma(x, y)) == '<mrow><mi>&#x393;</mi><mfenced><mi>x</mi><mi>y</mi></mfenced></mrow>' assert mpp.doprint(zeta(x)) == '<mrow><mi>&#x3B6;</mi><mfenced><mi>x</mi></mfenced></mrow>' assert mpp.doprint(zeta(x, y)) == '<mrow><mi>&#x3B6;</mi><mfenced><mi>x</mi><mi>y</mi></mfenced></mrow>' assert mpp.doprint(dirichlet_eta(x)) == '<mrow><mi>&#x3B7;</mi><mfenced><mi>x</mi></mfenced></mrow>' assert mpp.doprint(elliptic_k(x)) == '<mrow><mi>&#x39A;</mi><mfenced><mi>x</mi></mfenced></mrow>' assert mpp.doprint(totient(x)) == '<mrow><mi>&#x3D5;</mi><mfenced><mi>x</mi></mfenced></mrow>' assert mpp.doprint(reduced_totient(x)) == '<mrow><mi>&#x3BB;</mi><mfenced><mi>x</mi></mfenced></mrow>' assert mpp.doprint(primenu(x)) == '<mrow><mi>&#x3BD;</mi><mfenced><mi>x</mi></mfenced></mrow>' assert mpp.doprint(primeomega(x)) == '<mrow><mi>&#x3A9;</mi><mfenced><mi>x</mi></mfenced></mrow>' assert mpp.doprint(fresnels(x)) == '<mrow><mi>S</mi><mfenced><mi>x</mi></mfenced></mrow>' assert mpp.doprint(fresnelc(x)) == '<mrow><mi>C</mi><mfenced><mi>x</mi></mfenced></mrow>' assert mpp.doprint(Heaviside(x)) == '<mrow><mi>&#x398;</mi><mfenced><mi>x</mi><mfrac><mn>1</mn><mn>2</mn></mfrac></mfenced></mrow>' def test_mathml_builtins(): assert mpp.doprint(None) == '<mi>None</mi>' assert mpp.doprint(true) == '<mi>True</mi>' assert mpp.doprint(false) == '<mi>False</mi>' def test_mathml_Range(): assert mpp.doprint(Range(1, 51)) == \ '<mfenced close="}" open="{"><mn>1</mn><mn>2</mn><mi>&#8230;</mi><mn>50</mn></mfenced>' assert mpp.doprint(Range(1, 4)) == \ '<mfenced close="}" open="{"><mn>1</mn><mn>2</mn><mn>3</mn></mfenced>' assert mpp.doprint(Range(0, 3, 1)) == \ '<mfenced close="}" open="{"><mn>0</mn><mn>1</mn><mn>2</mn></mfenced>' assert mpp.doprint(Range(0, 30, 1)) == \ '<mfenced close="}" open="{"><mn>0</mn><mn>1</mn><mi>&#8230;</mi><mn>29</mn></mfenced>' assert mpp.doprint(Range(30, 1, -1)) == \ '<mfenced close="}" open="{"><mn>30</mn><mn>29</mn><mi>&#8230;</mi>'\ '<mn>2</mn></mfenced>' assert mpp.doprint(Range(0, oo, 2)) == \ '<mfenced close="}" open="{"><mn>0</mn><mn>2</mn><mi>&#8230;</mi></mfenced>' assert mpp.doprint(Range(oo, -2, -2)) == \ '<mfenced close="}" open="{"><mi>&#8230;</mi><mn>2</mn><mn>0</mn></mfenced>' assert mpp.doprint(Range(-2, -oo, -1)) == \ '<mfenced close="}" open="{"><mn>-2</mn><mn>-3</mn><mi>&#8230;</mi></mfenced>' def test_print_exp(): assert mpp.doprint(exp(x)) == \ '<msup><mi>&ExponentialE;</mi><mi>x</mi></msup>' assert mpp.doprint(exp(1) + exp(2)) == \ '<mrow><mi>&ExponentialE;</mi><mo>+</mo><msup><mi>&ExponentialE;</mi><mn>2</mn></msup></mrow>' def test_print_MinMax(): assert mpp.doprint(Min(x, y)) == \ '<mrow><mo>min</mo><mfenced><mi>x</mi><mi>y</mi></mfenced></mrow>' assert mpp.doprint(Min(x, 2, x**3)) == \ '<mrow><mo>min</mo><mfenced><mn>2</mn><mi>x</mi><msup><mi>x</mi>'\ '<mn>3</mn></msup></mfenced></mrow>' assert mpp.doprint(Max(x, y)) == \ '<mrow><mo>max</mo><mfenced><mi>x</mi><mi>y</mi></mfenced></mrow>' assert mpp.doprint(Max(x, 2, x**3)) == \ '<mrow><mo>max</mo><mfenced><mn>2</mn><mi>x</mi><msup><mi>x</mi>'\ '<mn>3</mn></msup></mfenced></mrow>' def test_mathml_presentation_numbers(): n = Symbol('n') assert mathml(catalan(n), printer='presentation') == \ '<msub><mi>C</mi><mi>n</mi></msub>' assert mathml(bernoulli(n), printer='presentation') == \ '<msub><mi>B</mi><mi>n</mi></msub>' assert mathml(bell(n), printer='presentation') == \ '<msub><mi>B</mi><mi>n</mi></msub>' assert mathml(euler(n), printer='presentation') == \ '<msub><mi>E</mi><mi>n</mi></msub>' assert mathml(fibonacci(n), printer='presentation') == \ '<msub><mi>F</mi><mi>n</mi></msub>' assert mathml(lucas(n), printer='presentation') == \ '<msub><mi>L</mi><mi>n</mi></msub>' assert mathml(tribonacci(n), printer='presentation') == \ '<msub><mi>T</mi><mi>n</mi></msub>' assert mathml(bernoulli(n, x), printer='presentation') == \ '<mrow><msub><mi>B</mi><mi>n</mi></msub><mfenced><mi>x</mi></mfenced></mrow>' assert mathml(bell(n, x), printer='presentation') == \ '<mrow><msub><mi>B</mi><mi>n</mi></msub><mfenced><mi>x</mi></mfenced></mrow>' assert mathml(euler(n, x), printer='presentation') == \ '<mrow><msub><mi>E</mi><mi>n</mi></msub><mfenced><mi>x</mi></mfenced></mrow>' assert mathml(fibonacci(n, x), printer='presentation') == \ '<mrow><msub><mi>F</mi><mi>n</mi></msub><mfenced><mi>x</mi></mfenced></mrow>' assert mathml(tribonacci(n, x), printer='presentation') == \ '<mrow><msub><mi>T</mi><mi>n</mi></msub><mfenced><mi>x</mi></mfenced></mrow>' def test_mathml_presentation_mathieu(): assert mathml(mathieuc(x, y, z), printer='presentation') == \ '<mrow><mi>C</mi><mfenced><mi>x</mi><mi>y</mi><mi>z</mi></mfenced></mrow>' assert mathml(mathieus(x, y, z), printer='presentation') == \ '<mrow><mi>S</mi><mfenced><mi>x</mi><mi>y</mi><mi>z</mi></mfenced></mrow>' assert mathml(mathieucprime(x, y, z), printer='presentation') == \ '<mrow><mi>C&#x2032;</mi><mfenced><mi>x</mi><mi>y</mi><mi>z</mi></mfenced></mrow>' assert mathml(mathieusprime(x, y, z), printer='presentation') == \ '<mrow><mi>S&#x2032;</mi><mfenced><mi>x</mi><mi>y</mi><mi>z</mi></mfenced></mrow>' def test_mathml_presentation_stieltjes(): assert mathml(stieltjes(n), printer='presentation') == \ '<msub><mi>&#x03B3;</mi><mi>n</mi></msub>' assert mathml(stieltjes(n, x), printer='presentation') == \ '<mrow><msub><mi>&#x03B3;</mi><mi>n</mi></msub><mfenced><mi>x</mi></mfenced></mrow>' def test_print_matrix_symbol(): A = MatrixSymbol('A', 1, 2) assert mpp.doprint(A) == '<mi>A</mi>' assert mp.doprint(A) == '<ci>A</ci>' assert mathml(A, printer='presentation', mat_symbol_style="bold") == \ '<mi mathvariant="bold">A</mi>' # No effect in content printer assert mathml(A, mat_symbol_style="bold") == '<ci>A</ci>' def test_print_hadamard(): from sympy.matrices.expressions import HadamardProduct from sympy.matrices.expressions import Transpose X = MatrixSymbol('X', 2, 2) Y = MatrixSymbol('Y', 2, 2) assert mathml(HadamardProduct(X, Y*Y), printer="presentation") == \ '<mrow>' \ '<mi>X</mi>' \ '<mo>&#x2218;</mo>' \ '<msup><mi>Y</mi><mn>2</mn></msup>' \ '</mrow>' assert mathml(HadamardProduct(X, Y)*Y, printer="presentation") == \ '<mrow>' \ '<mfenced>' \ '<mrow><mi>X</mi><mo>&#x2218;</mo><mi>Y</mi></mrow>' \ '</mfenced>' \ '<mo>&InvisibleTimes;</mo><mi>Y</mi>' \ '</mrow>' assert mathml(HadamardProduct(X, Y, Y), printer="presentation") == \ '<mrow>' \ '<mi>X</mi><mo>&#x2218;</mo>' \ '<mi>Y</mi><mo>&#x2218;</mo>' \ '<mi>Y</mi>' \ '</mrow>' assert mathml( Transpose(HadamardProduct(X, Y)), printer="presentation") == \ '<msup>' \ '<mfenced>' \ '<mrow><mi>X</mi><mo>&#x2218;</mo><mi>Y</mi></mrow>' \ '</mfenced>' \ '<mo>T</mo>' \ '</msup>' def test_print_random_symbol(): R = RandomSymbol(Symbol('R')) assert mpp.doprint(R) == '<mi>R</mi>' assert mp.doprint(R) == '<ci>R</ci>' def test_print_IndexedBase(): assert mathml(IndexedBase(a)[b], printer='presentation') == \ '<msub><mi>a</mi><mi>b</mi></msub>' assert mathml(IndexedBase(a)[b, c, d], printer='presentation') == \ '<msub><mi>a</mi><mfenced><mi>b</mi><mi>c</mi><mi>d</mi></mfenced></msub>' assert mathml(IndexedBase(a)[b]*IndexedBase(c)[d]*IndexedBase(e), printer='presentation') == \ '<mrow><msub><mi>a</mi><mi>b</mi></msub><mo>&InvisibleTimes;'\ '</mo><msub><mi>c</mi><mi>d</mi></msub><mo>&InvisibleTimes;</mo><mi>e</mi></mrow>' def test_print_Indexed(): assert mathml(IndexedBase(a), printer='presentation') == '<mi>a</mi>' assert mathml(IndexedBase(a/b), printer='presentation') == \ '<mrow><mfrac><mi>a</mi><mi>b</mi></mfrac></mrow>' assert mathml(IndexedBase((a, b)), printer='presentation') == \ '<mrow><mfenced><mi>a</mi><mi>b</mi></mfenced></mrow>' def test_print_MatrixElement(): i, j = symbols('i j') A = MatrixSymbol('A', i, j) assert mathml(A[0,0],printer = 'presentation') == \ '<msub><mi>A</mi><mfenced close="" open=""><mn>0</mn><mn>0</mn></mfenced></msub>' assert mathml(A[i,j], printer = 'presentation') == \ '<msub><mi>A</mi><mfenced close="" open=""><mi>i</mi><mi>j</mi></mfenced></msub>' assert mathml(A[i*j,0], printer = 'presentation') == \ '<msub><mi>A</mi><mfenced close="" open=""><mrow><mi>i</mi><mo>&InvisibleTimes;</mo><mi>j</mi></mrow><mn>0</mn></mfenced></msub>' def test_print_Vector(): ACS = CoordSys3D('A') assert mathml(Cross(ACS.i, ACS.j*ACS.x*3 + ACS.k), printer='presentation') == \ '<mrow><msub><mover><mi mathvariant="bold">i</mi><mo>^</mo></mover>'\ '<mi mathvariant="bold">A</mi></msub><mo>&#xD7;</mo><mfenced><mrow>'\ '<mfenced><mrow><mn>3</mn><mo>&InvisibleTimes;</mo><msub>'\ '<mi mathvariant="bold">x</mi><mi mathvariant="bold">A</mi></msub>'\ '</mrow></mfenced><mo>&InvisibleTimes;</mo><msub><mover>'\ '<mi mathvariant="bold">j</mi><mo>^</mo></mover>'\ '<mi mathvariant="bold">A</mi></msub><mo>+</mo><msub><mover>'\ '<mi mathvariant="bold">k</mi><mo>^</mo></mover><mi mathvariant="bold">'\ 'A</mi></msub></mrow></mfenced></mrow>' assert mathml(Cross(ACS.i, ACS.j), printer='presentation') == \ '<mrow><msub><mover><mi mathvariant="bold">i</mi><mo>^</mo></mover>'\ '<mi mathvariant="bold">A</mi></msub><mo>&#xD7;</mo><msub><mover>'\ '<mi mathvariant="bold">j</mi><mo>^</mo></mover>'\ '<mi mathvariant="bold">A</mi></msub></mrow>' assert mathml(x*Cross(ACS.i, ACS.j), printer='presentation') == \ '<mrow><mi>x</mi><mo>&InvisibleTimes;</mo><mfenced><mrow><msub><mover>'\ '<mi mathvariant="bold">i</mi><mo>^</mo></mover>'\ '<mi mathvariant="bold">A</mi></msub><mo>&#xD7;</mo><msub><mover>'\ '<mi mathvariant="bold">j</mi><mo>^</mo></mover>'\ '<mi mathvariant="bold">A</mi></msub></mrow></mfenced></mrow>' assert mathml(Cross(x*ACS.i, ACS.j), printer='presentation') == \ '<mrow><mo>-</mo><mrow><msub><mover><mi mathvariant="bold">j</mi>'\ '<mo>^</mo></mover><mi mathvariant="bold">A</mi></msub>'\ '<mo>&#xD7;</mo><mfenced><mrow><mfenced><mi>x</mi></mfenced>'\ '<mo>&InvisibleTimes;</mo><msub><mover><mi mathvariant="bold">i</mi>'\ '<mo>^</mo></mover><mi mathvariant="bold">A</mi></msub></mrow>'\ '</mfenced></mrow></mrow>' assert mathml(Curl(3*ACS.x*ACS.j), printer='presentation') == \ '<mrow><mo>&#x2207;</mo><mo>&#xD7;</mo><mfenced><mrow><mfenced><mrow>'\ '<mn>3</mn><mo>&InvisibleTimes;</mo><msub>'\ '<mi mathvariant="bold">x</mi><mi mathvariant="bold">A</mi></msub>'\ '</mrow></mfenced><mo>&InvisibleTimes;</mo><msub><mover>'\ '<mi mathvariant="bold">j</mi><mo>^</mo></mover>'\ '<mi mathvariant="bold">A</mi></msub></mrow></mfenced></mrow>' assert mathml(Curl(3*x*ACS.x*ACS.j), printer='presentation') == \ '<mrow><mo>&#x2207;</mo><mo>&#xD7;</mo><mfenced><mrow><mfenced><mrow>'\ '<mn>3</mn><mo>&InvisibleTimes;</mo><msub><mi mathvariant="bold">x'\ '</mi><mi mathvariant="bold">A</mi></msub><mo>&InvisibleTimes;</mo>'\ '<mi>x</mi></mrow></mfenced><mo>&InvisibleTimes;</mo><msub><mover>'\ '<mi mathvariant="bold">j</mi><mo>^</mo></mover>'\ '<mi mathvariant="bold">A</mi></msub></mrow></mfenced></mrow>' assert mathml(x*Curl(3*ACS.x*ACS.j), printer='presentation') == \ '<mrow><mi>x</mi><mo>&InvisibleTimes;</mo><mfenced><mrow><mo>&#x2207;</mo>'\ '<mo>&#xD7;</mo><mfenced><mrow><mfenced><mrow><mn>3</mn>'\ '<mo>&InvisibleTimes;</mo><msub><mi mathvariant="bold">x</mi>'\ '<mi mathvariant="bold">A</mi></msub></mrow></mfenced>'\ '<mo>&InvisibleTimes;</mo><msub><mover><mi mathvariant="bold">j</mi>'\ '<mo>^</mo></mover><mi mathvariant="bold">A</mi></msub></mrow>'\ '</mfenced></mrow></mfenced></mrow>' assert mathml(Curl(3*x*ACS.x*ACS.j + ACS.i), printer='presentation') == \ '<mrow><mo>&#x2207;</mo><mo>&#xD7;</mo><mfenced><mrow><msub><mover>'\ '<mi mathvariant="bold">i</mi><mo>^</mo></mover>'\ '<mi mathvariant="bold">A</mi></msub><mo>+</mo><mfenced><mrow>'\ '<mn>3</mn><mo>&InvisibleTimes;</mo><msub><mi mathvariant="bold">x'\ '</mi><mi mathvariant="bold">A</mi></msub><mo>&InvisibleTimes;</mo>'\ '<mi>x</mi></mrow></mfenced><mo>&InvisibleTimes;</mo><msub><mover>'\ '<mi mathvariant="bold">j</mi><mo>^</mo></mover>'\ '<mi mathvariant="bold">A</mi></msub></mrow></mfenced></mrow>' assert mathml(Divergence(3*ACS.x*ACS.j), printer='presentation') == \ '<mrow><mo>&#x2207;</mo><mo>&#xB7;</mo><mfenced><mrow><mfenced><mrow>'\ '<mn>3</mn><mo>&InvisibleTimes;</mo><msub><mi mathvariant="bold">x'\ '</mi><mi mathvariant="bold">A</mi></msub></mrow></mfenced>'\ '<mo>&InvisibleTimes;</mo><msub><mover><mi mathvariant="bold">j</mi>'\ '<mo>^</mo></mover><mi mathvariant="bold">A</mi></msub></mrow></mfenced></mrow>' assert mathml(x*Divergence(3*ACS.x*ACS.j), printer='presentation') == \ '<mrow><mi>x</mi><mo>&InvisibleTimes;</mo><mfenced><mrow><mo>&#x2207;</mo>'\ '<mo>&#xB7;</mo><mfenced><mrow><mfenced><mrow><mn>3</mn>'\ '<mo>&InvisibleTimes;</mo><msub><mi mathvariant="bold">x</mi>'\ '<mi mathvariant="bold">A</mi></msub></mrow></mfenced>'\ '<mo>&InvisibleTimes;</mo><msub><mover><mi mathvariant="bold">j</mi>'\ '<mo>^</mo></mover><mi mathvariant="bold">A</mi></msub></mrow>'\ '</mfenced></mrow></mfenced></mrow>' assert mathml(Divergence(3*x*ACS.x*ACS.j + ACS.i), printer='presentation') == \ '<mrow><mo>&#x2207;</mo><mo>&#xB7;</mo><mfenced><mrow><msub><mover>'\ '<mi mathvariant="bold">i</mi><mo>^</mo></mover>'\ '<mi mathvariant="bold">A</mi></msub><mo>+</mo><mfenced><mrow>'\ '<mn>3</mn><mo>&InvisibleTimes;</mo><msub>'\ '<mi mathvariant="bold">x</mi><mi mathvariant="bold">A</mi></msub>'\ '<mo>&InvisibleTimes;</mo><mi>x</mi></mrow></mfenced>'\ '<mo>&InvisibleTimes;</mo><msub><mover><mi mathvariant="bold">j</mi>'\ '<mo>^</mo></mover><mi mathvariant="bold">A</mi></msub></mrow></mfenced></mrow>' assert mathml(Dot(ACS.i, ACS.j*ACS.x*3+ACS.k), printer='presentation') == \ '<mrow><msub><mover><mi mathvariant="bold">i</mi><mo>^</mo></mover>'\ '<mi mathvariant="bold">A</mi></msub><mo>&#xB7;</mo><mfenced><mrow>'\ '<mfenced><mrow><mn>3</mn><mo>&InvisibleTimes;</mo><msub>'\ '<mi mathvariant="bold">x</mi><mi mathvariant="bold">A</mi></msub>'\ '</mrow></mfenced><mo>&InvisibleTimes;</mo><msub><mover>'\ '<mi mathvariant="bold">j</mi><mo>^</mo></mover>'\ '<mi mathvariant="bold">A</mi></msub><mo>+</mo><msub><mover>'\ '<mi mathvariant="bold">k</mi><mo>^</mo></mover>'\ '<mi mathvariant="bold">A</mi></msub></mrow></mfenced></mrow>' assert mathml(Dot(ACS.i, ACS.j), printer='presentation') == \ '<mrow><msub><mover><mi mathvariant="bold">i</mi><mo>^</mo></mover>'\ '<mi mathvariant="bold">A</mi></msub><mo>&#xB7;</mo><msub><mover>'\ '<mi mathvariant="bold">j</mi><mo>^</mo></mover>'\ '<mi mathvariant="bold">A</mi></msub></mrow>' assert mathml(Dot(x*ACS.i, ACS.j), printer='presentation') == \ '<mrow><msub><mover><mi mathvariant="bold">j</mi><mo>^</mo></mover>'\ '<mi mathvariant="bold">A</mi></msub><mo>&#xB7;</mo><mfenced><mrow>'\ '<mfenced><mi>x</mi></mfenced><mo>&InvisibleTimes;</mo><msub><mover>'\ '<mi mathvariant="bold">i</mi><mo>^</mo></mover>'\ '<mi mathvariant="bold">A</mi></msub></mrow></mfenced></mrow>' assert mathml(x*Dot(ACS.i, ACS.j), printer='presentation') == \ '<mrow><mi>x</mi><mo>&InvisibleTimes;</mo><mfenced><mrow><msub><mover>'\ '<mi mathvariant="bold">i</mi><mo>^</mo></mover>'\ '<mi mathvariant="bold">A</mi></msub><mo>&#xB7;</mo><msub><mover>'\ '<mi mathvariant="bold">j</mi><mo>^</mo></mover>'\ '<mi mathvariant="bold">A</mi></msub></mrow></mfenced></mrow>' assert mathml(Gradient(ACS.x), printer='presentation') == \ '<mrow><mo>&#x2207;</mo><msub><mi mathvariant="bold">x</mi>'\ '<mi mathvariant="bold">A</mi></msub></mrow>' assert mathml(Gradient(ACS.x + 3*ACS.y), printer='presentation') == \ '<mrow><mo>&#x2207;</mo><mfenced><mrow><msub><mi mathvariant="bold">'\ 'x</mi><mi mathvariant="bold">A</mi></msub><mo>+</mo><mrow><mn>3</mn>'\ '<mo>&InvisibleTimes;</mo><msub><mi mathvariant="bold">y</mi>'\ '<mi mathvariant="bold">A</mi></msub></mrow></mrow></mfenced></mrow>' assert mathml(x*Gradient(ACS.x), printer='presentation') == \ '<mrow><mi>x</mi><mo>&InvisibleTimes;</mo><mfenced><mrow><mo>&#x2207;</mo>'\ '<msub><mi mathvariant="bold">x</mi><mi mathvariant="bold">A</mi>'\ '</msub></mrow></mfenced></mrow>' assert mathml(Gradient(x*ACS.x), printer='presentation') == \ '<mrow><mo>&#x2207;</mo><mfenced><mrow><msub><mi mathvariant="bold">'\ 'x</mi><mi mathvariant="bold">A</mi></msub><mo>&InvisibleTimes;</mo>'\ '<mi>x</mi></mrow></mfenced></mrow>' assert mathml(Cross(ACS.x, ACS.z) + Cross(ACS.z, ACS.x), printer='presentation') == \ '<mover><mi mathvariant="bold">0</mi><mo>^</mo></mover>' assert mathml(Cross(ACS.z, ACS.x), printer='presentation') == \ '<mrow><mo>-</mo><mrow><msub><mi mathvariant="bold">x</mi>'\ '<mi mathvariant="bold">A</mi></msub><mo>&#xD7;</mo><msub>'\ '<mi mathvariant="bold">z</mi><mi mathvariant="bold">A</mi></msub></mrow></mrow>' assert mathml(Laplacian(ACS.x), printer='presentation') == \ '<mrow><mo>&#x2206;</mo><msub><mi mathvariant="bold">x</mi>'\ '<mi mathvariant="bold">A</mi></msub></mrow>' assert mathml(Laplacian(ACS.x + 3*ACS.y), printer='presentation') == \ '<mrow><mo>&#x2206;</mo><mfenced><mrow><msub><mi mathvariant="bold">'\ 'x</mi><mi mathvariant="bold">A</mi></msub><mo>+</mo><mrow><mn>3</mn>'\ '<mo>&InvisibleTimes;</mo><msub><mi mathvariant="bold">y</mi>'\ '<mi mathvariant="bold">A</mi></msub></mrow></mrow></mfenced></mrow>' assert mathml(x*Laplacian(ACS.x), printer='presentation') == \ '<mrow><mi>x</mi><mo>&InvisibleTimes;</mo><mfenced><mrow><mo>&#x2206;</mo>'\ '<msub><mi mathvariant="bold">x</mi><mi mathvariant="bold">A</mi>'\ '</msub></mrow></mfenced></mrow>' assert mathml(Laplacian(x*ACS.x), printer='presentation') == \ '<mrow><mo>&#x2206;</mo><mfenced><mrow><msub><mi mathvariant="bold">'\ 'x</mi><mi mathvariant="bold">A</mi></msub><mo>&InvisibleTimes;</mo>'\ '<mi>x</mi></mrow></mfenced></mrow>' def test_print_elliptic_f(): assert mathml(elliptic_f(x, y), printer = 'presentation') == \ '<mrow><mi>&#x1d5a5;</mi><mfenced separators="|"><mi>x</mi><mi>y</mi></mfenced></mrow>' assert mathml(elliptic_f(x/y, y), printer = 'presentation') == \ '<mrow><mi>&#x1d5a5;</mi><mfenced separators="|"><mrow><mfrac><mi>x</mi><mi>y</mi></mfrac></mrow><mi>y</mi></mfenced></mrow>' def test_print_elliptic_e(): assert mathml(elliptic_e(x), printer = 'presentation') == \ '<mrow><mi>&#x1d5a4;</mi><mfenced separators="|"><mi>x</mi></mfenced></mrow>' assert mathml(elliptic_e(x, y), printer = 'presentation') == \ '<mrow><mi>&#x1d5a4;</mi><mfenced separators="|"><mi>x</mi><mi>y</mi></mfenced></mrow>' def test_print_elliptic_pi(): assert mathml(elliptic_pi(x, y), printer = 'presentation') == \ '<mrow><mi>&#x1d6f1;</mi><mfenced separators="|"><mi>x</mi><mi>y</mi></mfenced></mrow>' assert mathml(elliptic_pi(x, y, z), printer = 'presentation') == \ '<mrow><mi>&#x1d6f1;</mi><mfenced separators=";|"><mi>x</mi><mi>y</mi><mi>z</mi></mfenced></mrow>' def test_print_Ei(): assert mathml(Ei(x), printer = 'presentation') == \ '<mrow><mi>Ei</mi><mfenced><mi>x</mi></mfenced></mrow>' assert mathml(Ei(x**y), printer = 'presentation') == \ '<mrow><mi>Ei</mi><mfenced><msup><mi>x</mi><mi>y</mi></msup></mfenced></mrow>' def test_print_expint(): assert mathml(expint(x, y), printer = 'presentation') == \ '<mrow><msub><mo>E</mo><mi>x</mi></msub><mfenced><mi>y</mi></mfenced></mrow>' assert mathml(expint(IndexedBase(x)[1], IndexedBase(x)[2]), printer = 'presentation') == \ '<mrow><msub><mo>E</mo><msub><mi>x</mi><mn>1</mn></msub></msub><mfenced><msub><mi>x</mi><mn>2</mn></msub></mfenced></mrow>' def test_print_jacobi(): assert mathml(jacobi(n, a, b, x), printer = 'presentation') == \ '<mrow><msubsup><mo>P</mo><mi>n</mi><mfenced><mi>a</mi><mi>b</mi></mfenced></msubsup><mfenced><mi>x</mi></mfenced></mrow>' def test_print_gegenbauer(): assert mathml(gegenbauer(n, a, x), printer = 'presentation') == \ '<mrow><msubsup><mo>C</mo><mi>n</mi><mfenced><mi>a</mi></mfenced></msubsup><mfenced><mi>x</mi></mfenced></mrow>' def test_print_chebyshevt(): assert mathml(chebyshevt(n, x), printer = 'presentation') == \ '<mrow><msub><mo>T</mo><mi>n</mi></msub><mfenced><mi>x</mi></mfenced></mrow>' def test_print_chebyshevu(): assert mathml(chebyshevu(n, x), printer = 'presentation') == \ '<mrow><msub><mo>U</mo><mi>n</mi></msub><mfenced><mi>x</mi></mfenced></mrow>' def test_print_legendre(): assert mathml(legendre(n, x), printer = 'presentation') == \ '<mrow><msub><mo>P</mo><mi>n</mi></msub><mfenced><mi>x</mi></mfenced></mrow>' def test_print_assoc_legendre(): assert mathml(assoc_legendre(n, a, x), printer = 'presentation') == \ '<mrow><msubsup><mo>P</mo><mi>n</mi><mfenced><mi>a</mi></mfenced></msubsup><mfenced><mi>x</mi></mfenced></mrow>' def test_print_laguerre(): assert mathml(laguerre(n, x), printer = 'presentation') == \ '<mrow><msub><mo>L</mo><mi>n</mi></msub><mfenced><mi>x</mi></mfenced></mrow>' def test_print_assoc_laguerre(): assert mathml(assoc_laguerre(n, a, x), printer = 'presentation') == \ '<mrow><msubsup><mo>L</mo><mi>n</mi><mfenced><mi>a</mi></mfenced></msubsup><mfenced><mi>x</mi></mfenced></mrow>' def test_print_hermite(): assert mathml(hermite(n, x), printer = 'presentation') == \ '<mrow><msub><mo>H</mo><mi>n</mi></msub><mfenced><mi>x</mi></mfenced></mrow>' def test_mathml_SingularityFunction(): assert mathml(SingularityFunction(x, 4, 5), printer='presentation') == \ '<msup><mfenced close="&#10217;" open="&#10216;"><mrow><mi>x</mi>' \ '<mo>-</mo><mn>4</mn></mrow></mfenced><mn>5</mn></msup>' assert mathml(SingularityFunction(x, -3, 4), printer='presentation') == \ '<msup><mfenced close="&#10217;" open="&#10216;"><mrow><mi>x</mi>' \ '<mo>+</mo><mn>3</mn></mrow></mfenced><mn>4</mn></msup>' assert mathml(SingularityFunction(x, 0, 4), printer='presentation') == \ '<msup><mfenced close="&#10217;" open="&#10216;"><mi>x</mi></mfenced>' \ '<mn>4</mn></msup>' assert mathml(SingularityFunction(x, a, n), printer='presentation') == \ '<msup><mfenced close="&#10217;" open="&#10216;"><mrow><mrow>' \ '<mo>-</mo><mi>a</mi></mrow><mo>+</mo><mi>x</mi></mrow></mfenced>' \ '<mi>n</mi></msup>' assert mathml(SingularityFunction(x, 4, -2), printer='presentation') == \ '<msup><mfenced close="&#10217;" open="&#10216;"><mrow><mi>x</mi>' \ '<mo>-</mo><mn>4</mn></mrow></mfenced><mn>-2</mn></msup>' assert mathml(SingularityFunction(x, 4, -1), printer='presentation') == \ '<msup><mfenced close="&#10217;" open="&#10216;"><mrow><mi>x</mi>' \ '<mo>-</mo><mn>4</mn></mrow></mfenced><mn>-1</mn></msup>' def test_mathml_matrix_functions(): from sympy.matrices import MatrixSymbol, Adjoint, Inverse, Transpose X = MatrixSymbol('X', 2, 2) Y = MatrixSymbol('Y', 2, 2) assert mathml(Adjoint(X), printer='presentation') == \ '<msup><mi>X</mi><mo>&#x2020;</mo></msup>' assert mathml(Adjoint(X + Y), printer='presentation') == \ '<msup><mfenced><mrow><mi>X</mi><mo>+</mo><mi>Y</mi></mrow></mfenced><mo>&#x2020;</mo></msup>' assert mathml(Adjoint(X) + Adjoint(Y), printer='presentation') == \ '<mrow><msup><mi>X</mi><mo>&#x2020;</mo></msup><mo>+</mo><msup>' \ '<mi>Y</mi><mo>&#x2020;</mo></msup></mrow>' assert mathml(Adjoint(X*Y), printer='presentation') == \ '<msup><mfenced><mrow><mi>X</mi><mo>&InvisibleTimes;</mo>' \ '<mi>Y</mi></mrow></mfenced><mo>&#x2020;</mo></msup>' assert mathml(Adjoint(Y)*Adjoint(X), printer='presentation') == \ '<mrow><msup><mi>Y</mi><mo>&#x2020;</mo></msup><mo>&InvisibleTimes;' \ '</mo><msup><mi>X</mi><mo>&#x2020;</mo></msup></mrow>' assert mathml(Adjoint(X**2), printer='presentation') == \ '<msup><mfenced><msup><mi>X</mi><mn>2</mn></msup></mfenced><mo>&#x2020;</mo></msup>' assert mathml(Adjoint(X)**2, printer='presentation') == \ '<msup><mfenced><msup><mi>X</mi><mo>&#x2020;</mo></msup></mfenced><mn>2</mn></msup>' assert mathml(Adjoint(Inverse(X)), printer='presentation') == \ '<msup><mfenced><msup><mi>X</mi><mn>-1</mn></msup></mfenced><mo>&#x2020;</mo></msup>' assert mathml(Inverse(Adjoint(X)), printer='presentation') == \ '<msup><mfenced><msup><mi>X</mi><mo>&#x2020;</mo></msup></mfenced><mn>-1</mn></msup>' assert mathml(Adjoint(Transpose(X)), printer='presentation') == \ '<msup><mfenced><msup><mi>X</mi><mo>T</mo></msup></mfenced><mo>&#x2020;</mo></msup>' assert mathml(Transpose(Adjoint(X)), printer='presentation') == \ '<msup><mfenced><msup><mi>X</mi><mo>&#x2020;</mo></msup></mfenced><mo>T</mo></msup>' assert mathml(Transpose(Adjoint(X) + Y), printer='presentation') == \ '<msup><mfenced><mrow><msup><mi>X</mi><mo>&#x2020;</mo></msup>' \ '<mo>+</mo><mi>Y</mi></mrow></mfenced><mo>T</mo></msup>' assert mathml(Transpose(X), printer='presentation') == \ '<msup><mi>X</mi><mo>T</mo></msup>' assert mathml(Transpose(X + Y), printer='presentation') == \ '<msup><mfenced><mrow><mi>X</mi><mo>+</mo><mi>Y</mi></mrow></mfenced><mo>T</mo></msup>' def test_mathml_special_matrices(): from sympy.matrices import Identity, ZeroMatrix, OneMatrix assert mathml(Identity(4), printer='presentation') == '<mi>&#x1D540;</mi>' assert mathml(ZeroMatrix(2, 2), printer='presentation') == '<mn>&#x1D7D8</mn>' assert mathml(OneMatrix(2, 2), printer='presentation') == '<mn>&#x1D7D9</mn>' def test_mathml_piecewise(): from sympy import Piecewise # Content MathML assert mathml(Piecewise((x, x <= 1), (x**2, True))) == \ '<piecewise><piece><ci>x</ci><apply><leq/><ci>x</ci><cn>1</cn></apply></piece><otherwise><apply><power/><ci>x</ci><cn>2</cn></apply></otherwise></piecewise>' raises(ValueError, lambda: mathml(Piecewise((x, x <= 1)))) def test_issue_17857(): assert mathml(Range(-oo, oo), printer='presentation') == \ '<mfenced close="}" open="{"><mi>&#8230;</mi><mn>-1</mn><mn>0</mn><mn>1</mn><mi>&#8230;</mi></mfenced>' assert mathml(Range(oo, -oo, -1), printer='presentation') == \ '<mfenced close="}" open="{"><mi>&#8230;</mi><mn>1</mn><mn>0</mn><mn>-1</mn><mi>&#8230;</mi></mfenced>' def test_float_roundtrip(): x = sympify(0.8975979010256552) y = float(mp.doprint(x).strip('</cn>')) assert x == y
800a83128b0d1468bbcea4ba1886c5f711a1d5bdd6ebd91be1c03d9325433674
""" Important note on tests in this module - the Theano printing functions use a global cache by default, which means that tests using it will modify global state and thus not be independent from each other. Instead of using the "cache" keyword argument each time, this module uses the theano_code_ and theano_function_ functions defined below which default to using a new, empty cache instead. """ import logging from sympy.external import import_module from sympy.testing.pytest import raises, SKIP, warns_deprecated_sympy theanologger = logging.getLogger('theano.configdefaults') theanologger.setLevel(logging.CRITICAL) theano = import_module('theano') theanologger.setLevel(logging.WARNING) if theano: import numpy as np ts = theano.scalar tt = theano.tensor xt, yt, zt = [tt.scalar(name, 'floatX') for name in 'xyz'] Xt, Yt, Zt = [tt.tensor('floatX', (False, False), name=n) for n in 'XYZ'] else: #bin/test will not execute any tests now disabled = True import sympy as sy from sympy import S from sympy.abc import x, y, z, t from sympy.printing.theanocode import (theano_code, dim_handling, theano_function) # Default set of matrix symbols for testing - make square so we can both # multiply and perform elementwise operations between them. X, Y, Z = [sy.MatrixSymbol(n, 4, 4) for n in 'XYZ'] # For testing AppliedUndef f_t = sy.Function('f')(t) def theano_code_(expr, **kwargs): """ Wrapper for theano_code that uses a new, empty cache by default. """ kwargs.setdefault('cache', {}) with warns_deprecated_sympy(): return theano_code(expr, **kwargs) def theano_function_(inputs, outputs, **kwargs): """ Wrapper for theano_function that uses a new, empty cache by default. """ kwargs.setdefault('cache', {}) with warns_deprecated_sympy(): return theano_function(inputs, outputs, **kwargs) def fgraph_of(*exprs): """ Transform SymPy expressions into Theano Computation. Parameters ========== exprs Sympy expressions Returns ======= theano.gof.FunctionGraph """ outs = list(map(theano_code_, exprs)) ins = theano.gof.graph.inputs(outs) ins, outs = theano.gof.graph.clone(ins, outs) return theano.gof.FunctionGraph(ins, outs) def theano_simplify(fgraph): """ Simplify a Theano Computation. Parameters ========== fgraph : theano.gof.FunctionGraph Returns ======= theano.gof.FunctionGraph """ mode = theano.compile.get_default_mode().excluding("fusion") fgraph = fgraph.clone() mode.optimizer.optimize(fgraph) return fgraph def theq(a, b): """ Test two Theano objects for equality. Also accepts numeric types and lists/tuples of supported types. Note - debugprint() has a bug where it will accept numeric types but does not respect the "file" argument and in this case and instead prints the number to stdout and returns an empty string. This can lead to tests passing where they should fail because any two numbers will always compare as equal. To prevent this we treat numbers as a separate case. """ numeric_types = (int, float, np.number) a_is_num = isinstance(a, numeric_types) b_is_num = isinstance(b, numeric_types) # Compare numeric types using regular equality if a_is_num or b_is_num: if not (a_is_num and b_is_num): return False return a == b # Compare sequences element-wise a_is_seq = isinstance(a, (tuple, list)) b_is_seq = isinstance(b, (tuple, list)) if a_is_seq or b_is_seq: if not (a_is_seq and b_is_seq) or type(a) != type(b): return False return list(map(theq, a)) == list(map(theq, b)) # Otherwise, assume debugprint() can handle it astr = theano.printing.debugprint(a, file='str') bstr = theano.printing.debugprint(b, file='str') # Check for bug mentioned above for argname, argval, argstr in [('a', a, astr), ('b', b, bstr)]: if argstr == '': raise TypeError( 'theano.printing.debugprint(%s) returned empty string ' '(%s is instance of %r)' % (argname, argname, type(argval)) ) return astr == bstr def test_example_symbols(): """ Check that the example symbols in this module print to their Theano equivalents, as many of the other tests depend on this. """ assert theq(xt, theano_code_(x)) assert theq(yt, theano_code_(y)) assert theq(zt, theano_code_(z)) assert theq(Xt, theano_code_(X)) assert theq(Yt, theano_code_(Y)) assert theq(Zt, theano_code_(Z)) def test_Symbol(): """ Test printing a Symbol to a theano variable. """ xx = theano_code_(x) assert isinstance(xx, (tt.TensorVariable, ts.ScalarVariable)) assert xx.broadcastable == () assert xx.name == x.name xx2 = theano_code_(x, broadcastables={x: (False,)}) assert xx2.broadcastable == (False,) assert xx2.name == x.name def test_MatrixSymbol(): """ Test printing a MatrixSymbol to a theano variable. """ XX = theano_code_(X) assert isinstance(XX, tt.TensorVariable) assert XX.broadcastable == (False, False) @SKIP # TODO - this is currently not checked but should be implemented def test_MatrixSymbol_wrong_dims(): """ Test MatrixSymbol with invalid broadcastable. """ bcs = [(), (False,), (True,), (True, False), (False, True,), (True, True)] for bc in bcs: with raises(ValueError): theano_code_(X, broadcastables={X: bc}) def test_AppliedUndef(): """ Test printing AppliedUndef instance, which works similarly to Symbol. """ ftt = theano_code_(f_t) assert isinstance(ftt, tt.TensorVariable) assert ftt.broadcastable == () assert ftt.name == 'f_t' def test_add(): expr = x + y comp = theano_code_(expr) assert comp.owner.op == theano.tensor.add def test_trig(): assert theq(theano_code_(sy.sin(x)), tt.sin(xt)) assert theq(theano_code_(sy.tan(x)), tt.tan(xt)) def test_many(): """ Test printing a complex expression with multiple symbols. """ expr = sy.exp(x**2 + sy.cos(y)) * sy.log(2*z) comp = theano_code_(expr) expected = tt.exp(xt**2 + tt.cos(yt)) * tt.log(2*zt) assert theq(comp, expected) def test_dtype(): """ Test specifying specific data types through the dtype argument. """ for dtype in ['float32', 'float64', 'int8', 'int16', 'int32', 'int64']: assert theano_code_(x, dtypes={x: dtype}).type.dtype == dtype # "floatX" type assert theano_code_(x, dtypes={x: 'floatX'}).type.dtype in ('float32', 'float64') # Type promotion assert theano_code_(x + 1, dtypes={x: 'float32'}).type.dtype == 'float32' assert theano_code_(x + y, dtypes={x: 'float64', y: 'float32'}).type.dtype == 'float64' def test_broadcastables(): """ Test the "broadcastables" argument when printing symbol-like objects. """ # No restrictions on shape for s in [x, f_t]: for bc in [(), (False,), (True,), (False, False), (True, False)]: assert theano_code_(s, broadcastables={s: bc}).broadcastable == bc # TODO - matrix broadcasting? def test_broadcasting(): """ Test "broadcastable" attribute after applying element-wise binary op. """ expr = x + y cases = [ [(), (), ()], [(False,), (False,), (False,)], [(True,), (False,), (False,)], [(False, True), (False, False), (False, False)], [(True, False), (False, False), (False, False)], ] for bc1, bc2, bc3 in cases: comp = theano_code_(expr, broadcastables={x: bc1, y: bc2}) assert comp.broadcastable == bc3 def test_MatMul(): expr = X*Y*Z expr_t = theano_code_(expr) assert isinstance(expr_t.owner.op, tt.Dot) assert theq(expr_t, Xt.dot(Yt).dot(Zt)) def test_Transpose(): assert isinstance(theano_code_(X.T).owner.op, tt.DimShuffle) def test_MatAdd(): expr = X+Y+Z assert isinstance(theano_code_(expr).owner.op, tt.Elemwise) def test_Rationals(): assert theq(theano_code_(sy.Integer(2) / 3), tt.true_div(2, 3)) assert theq(theano_code_(S.Half), tt.true_div(1, 2)) def test_Integers(): assert theano_code_(sy.Integer(3)) == 3 def test_factorial(): n = sy.Symbol('n') assert theano_code_(sy.factorial(n)) def test_Derivative(): simp = lambda expr: theano_simplify(fgraph_of(expr)) assert theq(simp(theano_code_(sy.Derivative(sy.sin(x), x, evaluate=False))), simp(theano.grad(tt.sin(xt), xt))) def test_theano_function_simple(): """ Test theano_function() with single output. """ f = theano_function_([x, y], [x+y]) assert f(2, 3) == 5 def test_theano_function_multi(): """ Test theano_function() with multiple outputs. """ f = theano_function_([x, y], [x+y, x-y]) o1, o2 = f(2, 3) assert o1 == 5 assert o2 == -1 def test_theano_function_numpy(): """ Test theano_function() vs Numpy implementation. """ f = theano_function_([x, y], [x+y], dim=1, dtypes={x: 'float64', y: 'float64'}) assert np.linalg.norm(f([1, 2], [3, 4]) - np.asarray([4, 6])) < 1e-9 f = theano_function_([x, y], [x+y], dtypes={x: 'float64', y: 'float64'}, dim=1) xx = np.arange(3).astype('float64') yy = 2*np.arange(3).astype('float64') assert np.linalg.norm(f(xx, yy) - 3*np.arange(3)) < 1e-9 def test_theano_function_matrix(): m = sy.Matrix([[x, y], [z, x + y + z]]) expected = np.array([[1.0, 2.0], [3.0, 1.0 + 2.0 + 3.0]]) f = theano_function_([x, y, z], [m]) np.testing.assert_allclose(f(1.0, 2.0, 3.0), expected) f = theano_function_([x, y, z], [m], scalar=True) np.testing.assert_allclose(f(1.0, 2.0, 3.0), expected) f = theano_function_([x, y, z], [m, m]) assert isinstance(f(1.0, 2.0, 3.0), type([])) np.testing.assert_allclose(f(1.0, 2.0, 3.0)[0], expected) np.testing.assert_allclose(f(1.0, 2.0, 3.0)[1], expected) def test_dim_handling(): assert dim_handling([x], dim=2) == {x: (False, False)} assert dim_handling([x, y], dims={x: 1, y: 2}) == {x: (False, True), y: (False, False)} assert dim_handling([x], broadcastables={x: (False,)}) == {x: (False,)} def test_theano_function_kwargs(): """ Test passing additional kwargs from theano_function() to theano.function(). """ import numpy as np f = theano_function_([x, y, z], [x+y], dim=1, on_unused_input='ignore', dtypes={x: 'float64', y: 'float64', z: 'float64'}) assert np.linalg.norm(f([1, 2], [3, 4], [0, 0]) - np.asarray([4, 6])) < 1e-9 f = theano_function_([x, y, z], [x+y], dtypes={x: 'float64', y: 'float64', z: 'float64'}, dim=1, on_unused_input='ignore') xx = np.arange(3).astype('float64') yy = 2*np.arange(3).astype('float64') zz = 2*np.arange(3).astype('float64') assert np.linalg.norm(f(xx, yy, zz) - 3*np.arange(3)) < 1e-9 def test_theano_function_scalar(): """ Test the "scalar" argument to theano_function(). """ args = [ ([x, y], [x + y], None, [0]), # Single 0d output ([X, Y], [X + Y], None, [2]), # Single 2d output ([x, y], [x + y], {x: 0, y: 1}, [1]), # Single 1d output ([x, y], [x + y, x - y], None, [0, 0]), # Two 0d outputs ([x, y, X, Y], [x + y, X + Y], None, [0, 2]), # One 0d output, one 2d ] # Create and test functions with and without the scalar setting for inputs, outputs, in_dims, out_dims in args: for scalar in [False, True]: f = theano_function_(inputs, outputs, dims=in_dims, scalar=scalar) # Check the theano_function attribute is set whether wrapped or not assert isinstance(f.theano_function, theano.compile.function_module.Function) # Feed in inputs of the appropriate size and get outputs in_values = [ np.ones([1 if bc else 5 for bc in i.type.broadcastable]) for i in f.theano_function.input_storage ] out_values = f(*in_values) if not isinstance(out_values, list): out_values = [out_values] # Check output types and shapes assert len(out_dims) == len(out_values) for d, value in zip(out_dims, out_values): if scalar and d == 0: # Should have been converted to a scalar value assert isinstance(value, np.number) else: # Otherwise should be an array assert isinstance(value, np.ndarray) assert value.ndim == d def test_theano_function_bad_kwarg(): """ Passing an unknown keyword argument to theano_function() should raise an exception. """ raises(Exception, lambda : theano_function_([x], [x+1], foobar=3)) def test_slice(): assert theano_code_(slice(1, 2, 3)) == slice(1, 2, 3) def theq_slice(s1, s2): for attr in ['start', 'stop', 'step']: a1 = getattr(s1, attr) a2 = getattr(s2, attr) if a1 is None or a2 is None: if not (a1 is None or a2 is None): return False elif not theq(a1, a2): return False return True dtypes = {x: 'int32', y: 'int32'} assert theq_slice(theano_code_(slice(x, y), dtypes=dtypes), slice(xt, yt)) assert theq_slice(theano_code_(slice(1, x, 3), dtypes=dtypes), slice(1, xt, 3)) def test_MatrixSlice(): from theano import Constant cache = {} n = sy.Symbol('n', integer=True) X = sy.MatrixSymbol('X', n, n) Y = X[1:2:3, 4:5:6] Yt = theano_code_(Y, cache=cache) s = ts.Scalar('int64') assert tuple(Yt.owner.op.idx_list) == (slice(s, s, s), slice(s, s, s)) assert Yt.owner.inputs[0] == theano_code_(X, cache=cache) # == doesn't work in theano like it does in SymPy. You have to use # equals. assert all(Yt.owner.inputs[i].equals(Constant(s, i)) for i in range(1, 7)) k = sy.Symbol('k') theano_code_(k, dtypes={k: 'int32'}) start, stop, step = 4, k, 2 Y = X[start:stop:step] Yt = theano_code_(Y, dtypes={n: 'int32', k: 'int32'}) # assert Yt.owner.op.idx_list[0].stop == kt def test_BlockMatrix(): n = sy.Symbol('n', integer=True) A, B, C, D = [sy.MatrixSymbol(name, n, n) for name in 'ABCD'] At, Bt, Ct, Dt = map(theano_code_, (A, B, C, D)) Block = sy.BlockMatrix([[A, B], [C, D]]) Blockt = theano_code_(Block) solutions = [tt.join(0, tt.join(1, At, Bt), tt.join(1, Ct, Dt)), tt.join(1, tt.join(0, At, Ct), tt.join(0, Bt, Dt))] assert any(theq(Blockt, solution) for solution in solutions) @SKIP def test_BlockMatrix_Inverse_execution(): k, n = 2, 4 dtype = 'float32' A = sy.MatrixSymbol('A', n, k) B = sy.MatrixSymbol('B', n, n) inputs = A, B output = B.I*A cutsizes = {A: [(n//2, n//2), (k//2, k//2)], B: [(n//2, n//2), (n//2, n//2)]} cutinputs = [sy.blockcut(i, *cutsizes[i]) for i in inputs] cutoutput = output.subs(dict(zip(inputs, cutinputs))) dtypes = dict(zip(inputs, [dtype]*len(inputs))) f = theano_function_(inputs, [output], dtypes=dtypes, cache={}) fblocked = theano_function_(inputs, [sy.block_collapse(cutoutput)], dtypes=dtypes, cache={}) ninputs = [np.random.rand(*x.shape).astype(dtype) for x in inputs] ninputs = [np.arange(n*k).reshape(A.shape).astype(dtype), np.eye(n).astype(dtype)] ninputs[1] += np.ones(B.shape)*1e-5 assert np.allclose(f(*ninputs), fblocked(*ninputs), rtol=1e-5) def test_DenseMatrix(): t = sy.Symbol('theta') for MatrixType in [sy.Matrix, sy.ImmutableMatrix]: X = MatrixType([[sy.cos(t), -sy.sin(t)], [sy.sin(t), sy.cos(t)]]) tX = theano_code_(X) assert isinstance(tX, tt.TensorVariable) assert tX.owner.op == tt.join_ def test_cache_basic(): """ Test single symbol-like objects are cached when printed by themselves. """ # Pairs of objects which should be considered equivalent with respect to caching pairs = [ (x, sy.Symbol('x')), (X, sy.MatrixSymbol('X', *X.shape)), (f_t, sy.Function('f')(sy.Symbol('t'))), ] for s1, s2 in pairs: cache = {} st = theano_code_(s1, cache=cache) # Test hit with same instance assert theano_code_(s1, cache=cache) is st # Test miss with same instance but new cache assert theano_code_(s1, cache={}) is not st # Test hit with different but equivalent instance assert theano_code_(s2, cache=cache) is st def test_global_cache(): """ Test use of the global cache. """ from sympy.printing.theanocode import global_cache backup = dict(global_cache) try: # Temporarily empty global cache global_cache.clear() for s in [x, X, f_t]: with warns_deprecated_sympy(): st = theano_code(s) assert theano_code(s) is st finally: # Restore global cache global_cache.update(backup) def test_cache_types_distinct(): """ Test that symbol-like objects of different types (Symbol, MatrixSymbol, AppliedUndef) are distinguished by the cache even if they have the same name. """ symbols = [sy.Symbol('f_t'), sy.MatrixSymbol('f_t', 4, 4), f_t] cache = {} # Single shared cache printed = {} for s in symbols: st = theano_code_(s, cache=cache) assert st not in printed.values() printed[s] = st # Check all printed objects are distinct assert len(set(map(id, printed.values()))) == len(symbols) # Check retrieving for s, st in printed.items(): with warns_deprecated_sympy(): assert theano_code(s, cache=cache) is st def test_symbols_are_created_once(): """ Test that a symbol is cached and reused when it appears in an expression more than once. """ expr = sy.Add(x, x, evaluate=False) comp = theano_code_(expr) assert theq(comp, xt + xt) assert not theq(comp, xt + theano_code_(x)) def test_cache_complex(): """ Test caching on a complicated expression with multiple symbols appearing multiple times. """ expr = x ** 2 + (y - sy.exp(x)) * sy.sin(z - x * y) symbol_names = {s.name for s in expr.free_symbols} expr_t = theano_code_(expr) # Iterate through variables in the Theano computational graph that the # printed expression depends on seen = set() for v in theano.gof.graph.ancestors([expr_t]): # Owner-less, non-constant variables should be our symbols if v.owner is None and not isinstance(v, theano.gof.graph.Constant): # Check it corresponds to a symbol and appears only once assert v.name in symbol_names assert v.name not in seen seen.add(v.name) # Check all were present assert seen == symbol_names def test_Piecewise(): # A piecewise linear expr = sy.Piecewise((0, x<0), (x, x<2), (1, True)) # ___/III result = theano_code_(expr) assert result.owner.op == tt.switch expected = tt.switch(xt<0, 0, tt.switch(xt<2, xt, 1)) assert theq(result, expected) expr = sy.Piecewise((x, x < 0)) result = theano_code_(expr) expected = tt.switch(xt < 0, xt, np.nan) assert theq(result, expected) expr = sy.Piecewise((0, sy.And(x>0, x<2)), \ (x, sy.Or(x>2, x<0))) result = theano_code_(expr) expected = tt.switch(tt.and_(xt>0,xt<2), 0, \ tt.switch(tt.or_(xt>2, xt<0), xt, np.nan)) assert theq(result, expected) def test_Relationals(): assert theq(theano_code_(sy.Eq(x, y)), tt.eq(xt, yt)) # assert theq(theano_code_(sy.Ne(x, y)), tt.neq(xt, yt)) # TODO - implement assert theq(theano_code_(x > y), xt > yt) assert theq(theano_code_(x < y), xt < yt) assert theq(theano_code_(x >= y), xt >= yt) assert theq(theano_code_(x <= y), xt <= yt) def test_complexfunctions(): with warns_deprecated_sympy(): xt, yt = theano_code_(x, dtypes={x:'complex128'}), theano_code_(y, dtypes={y: 'complex128'}) from sympy import conjugate from theano.tensor import as_tensor_variable as atv from theano.tensor import complex as cplx with warns_deprecated_sympy(): assert theq(theano_code_(y*conjugate(x)), yt*(xt.conj())) assert theq(theano_code_((1+2j)*x), xt*(atv(1.0)+atv(2.0)*cplx(0,1))) def test_constantfunctions(): with warns_deprecated_sympy(): tf = theano_function_([],[1+1j]) assert(tf()==1+1j)
5ced500f3a711cc0e691266e7b2dea06b0a3714880eeef9650046c1098cf8382
from sympy.core import (S, pi, oo, symbols, Function, Rational, Integer, Tuple, Symbol, EulerGamma, GoldenRatio, Catalan, Lambda, Mul, Pow, Mod, Eq, Ne, Le, Lt, Gt, Ge) from sympy.codegen.matrix_nodes import MatrixSolve from sympy.functions import (arg, atan2, bernoulli, beta, ceiling, chebyshevu, chebyshevt, conjugate, DiracDelta, exp, expint, factorial, floor, harmonic, Heaviside, im, laguerre, LambertW, log, Max, Min, Piecewise, polylog, re, RisingFactorial, sign, sinc, sqrt, zeta, binomial, legendre) from sympy.functions import (sin, cos, tan, cot, sec, csc, asin, acos, acot, atan, asec, acsc, sinh, cosh, tanh, coth, csch, sech, asinh, acosh, atanh, acoth, asech, acsch) from sympy.testing.pytest import raises, XFAIL from sympy.utilities.lambdify import implemented_function from sympy.matrices import (eye, Matrix, MatrixSymbol, Identity, HadamardProduct, SparseMatrix, HadamardPower) from sympy.functions.special.bessel import (jn, yn, besselj, bessely, besseli, besselk, hankel1, hankel2, airyai, airybi, airyaiprime, airybiprime) from sympy.functions.special.gamma_functions import (gamma, lowergamma, uppergamma, loggamma, polygamma) from sympy.functions.special.error_functions import (Chi, Ci, erf, erfc, erfi, erfcinv, erfinv, fresnelc, fresnels, li, Shi, Si, Li, erf2) from sympy import octave_code from sympy import octave_code as mcode x, y, z = symbols('x,y,z') def test_Integer(): assert mcode(Integer(67)) == "67" assert mcode(Integer(-1)) == "-1" def test_Rational(): assert mcode(Rational(3, 7)) == "3/7" assert mcode(Rational(18, 9)) == "2" assert mcode(Rational(3, -7)) == "-3/7" assert mcode(Rational(-3, -7)) == "3/7" assert mcode(x + Rational(3, 7)) == "x + 3/7" assert mcode(Rational(3, 7)*x) == "3*x/7" def test_Relational(): assert mcode(Eq(x, y)) == "x == y" assert mcode(Ne(x, y)) == "x != y" assert mcode(Le(x, y)) == "x <= y" assert mcode(Lt(x, y)) == "x < y" assert mcode(Gt(x, y)) == "x > y" assert mcode(Ge(x, y)) == "x >= y" def test_Function(): assert mcode(sin(x) ** cos(x)) == "sin(x).^cos(x)" assert mcode(sign(x)) == "sign(x)" assert mcode(exp(x)) == "exp(x)" assert mcode(log(x)) == "log(x)" assert mcode(factorial(x)) == "factorial(x)" assert mcode(floor(x)) == "floor(x)" assert mcode(atan2(y, x)) == "atan2(y, x)" assert mcode(beta(x, y)) == 'beta(x, y)' assert mcode(polylog(x, y)) == 'polylog(x, y)' assert mcode(harmonic(x)) == 'harmonic(x)' assert mcode(bernoulli(x)) == "bernoulli(x)" assert mcode(bernoulli(x, y)) == "bernoulli(x, y)" assert mcode(legendre(x, y)) == "legendre(x, y)" def test_Function_change_name(): assert mcode(abs(x)) == "abs(x)" assert mcode(ceiling(x)) == "ceil(x)" assert mcode(arg(x)) == "angle(x)" assert mcode(im(x)) == "imag(x)" assert mcode(re(x)) == "real(x)" assert mcode(conjugate(x)) == "conj(x)" assert mcode(chebyshevt(y, x)) == "chebyshevT(y, x)" assert mcode(chebyshevu(y, x)) == "chebyshevU(y, x)" assert mcode(laguerre(x, y)) == "laguerreL(x, y)" assert mcode(Chi(x)) == "coshint(x)" assert mcode(Shi(x)) == "sinhint(x)" assert mcode(Ci(x)) == "cosint(x)" assert mcode(Si(x)) == "sinint(x)" assert mcode(li(x)) == "logint(x)" assert mcode(loggamma(x)) == "gammaln(x)" assert mcode(polygamma(x, y)) == "psi(x, y)" assert mcode(RisingFactorial(x, y)) == "pochhammer(x, y)" assert mcode(DiracDelta(x)) == "dirac(x)" assert mcode(DiracDelta(x, 3)) == "dirac(3, x)" assert mcode(Heaviside(x)) == "heaviside(x, 1/2)" assert mcode(Heaviside(x, y)) == "heaviside(x, y)" assert mcode(binomial(x, y)) == "bincoeff(x, y)" assert mcode(Mod(x, y)) == "mod(x, y)" def test_minmax(): assert mcode(Max(x, y) + Min(x, y)) == "max(x, y) + min(x, y)" assert mcode(Max(x, y, z)) == "max(x, max(y, z))" assert mcode(Min(x, y, z)) == "min(x, min(y, z))" def test_Pow(): assert mcode(x**3) == "x.^3" assert mcode(x**(y**3)) == "x.^(y.^3)" assert mcode(x**Rational(2, 3)) == 'x.^(2/3)' g = implemented_function('g', Lambda(x, 2*x)) assert mcode(1/(g(x)*3.5)**(x - y**x)/(x**2 + y)) == \ "(3.5*2*x).^(-x + y.^x)./(x.^2 + y)" # For issue 14160 assert mcode(Mul(-2, x, Pow(Mul(y,y,evaluate=False), -1, evaluate=False), evaluate=False)) == '-2*x./(y.*y)' def test_basic_ops(): assert mcode(x*y) == "x.*y" assert mcode(x + y) == "x + y" assert mcode(x - y) == "x - y" assert mcode(-x) == "-x" def test_1_over_x_and_sqrt(): # 1.0 and 0.5 would do something different in regular StrPrinter, # but these are exact in IEEE floating point so no different here. assert mcode(1/x) == '1./x' assert mcode(x**-1) == mcode(x**-1.0) == '1./x' assert mcode(1/sqrt(x)) == '1./sqrt(x)' assert mcode(x**-S.Half) == mcode(x**-0.5) == '1./sqrt(x)' assert mcode(sqrt(x)) == 'sqrt(x)' assert mcode(x**S.Half) == mcode(x**0.5) == 'sqrt(x)' assert mcode(1/pi) == '1/pi' assert mcode(pi**-1) == mcode(pi**-1.0) == '1/pi' assert mcode(pi**-0.5) == '1/sqrt(pi)' def test_mix_number_mult_symbols(): assert mcode(3*x) == "3*x" assert mcode(pi*x) == "pi*x" assert mcode(3/x) == "3./x" assert mcode(pi/x) == "pi./x" assert mcode(x/3) == "x/3" assert mcode(x/pi) == "x/pi" assert mcode(x*y) == "x.*y" assert mcode(3*x*y) == "3*x.*y" assert mcode(3*pi*x*y) == "3*pi*x.*y" assert mcode(x/y) == "x./y" assert mcode(3*x/y) == "3*x./y" assert mcode(x*y/z) == "x.*y./z" assert mcode(x/y*z) == "x.*z./y" assert mcode(1/x/y) == "1./(x.*y)" assert mcode(2*pi*x/y/z) == "2*pi*x./(y.*z)" assert mcode(3*pi/x) == "3*pi./x" assert mcode(S(3)/5) == "3/5" assert mcode(S(3)/5*x) == "3*x/5" assert mcode(x/y/z) == "x./(y.*z)" assert mcode((x+y)/z) == "(x + y)./z" assert mcode((x+y)/(z+x)) == "(x + y)./(x + z)" assert mcode((x+y)/EulerGamma) == "(x + y)/%s" % EulerGamma.evalf(17) assert mcode(x/3/pi) == "x/(3*pi)" assert mcode(S(3)/5*x*y/pi) == "3*x.*y/(5*pi)" def test_mix_number_pow_symbols(): assert mcode(pi**3) == 'pi^3' assert mcode(x**2) == 'x.^2' assert mcode(x**(pi**3)) == 'x.^(pi^3)' assert mcode(x**y) == 'x.^y' assert mcode(x**(y**z)) == 'x.^(y.^z)' assert mcode((x**y)**z) == '(x.^y).^z' def test_imag(): I = S('I') assert mcode(I) == "1i" assert mcode(5*I) == "5i" assert mcode((S(3)/2)*I) == "3*1i/2" assert mcode(3+4*I) == "3 + 4i" assert mcode(sqrt(3)*I) == "sqrt(3)*1i" def test_constants(): assert mcode(pi) == "pi" assert mcode(oo) == "inf" assert mcode(-oo) == "-inf" assert mcode(S.NegativeInfinity) == "-inf" assert mcode(S.NaN) == "NaN" assert mcode(S.Exp1) == "exp(1)" assert mcode(exp(1)) == "exp(1)" def test_constants_other(): assert mcode(2*GoldenRatio) == "2*(1+sqrt(5))/2" assert mcode(2*Catalan) == "2*%s" % Catalan.evalf(17) assert mcode(2*EulerGamma) == "2*%s" % EulerGamma.evalf(17) def test_boolean(): assert mcode(x & y) == "x & y" assert mcode(x | y) == "x | y" assert mcode(~x) == "~x" assert mcode(x & y & z) == "x & y & z" assert mcode(x | y | z) == "x | y | z" assert mcode((x & y) | z) == "z | x & y" assert mcode((x | y) & z) == "z & (x | y)" def test_KroneckerDelta(): from sympy.functions import KroneckerDelta assert mcode(KroneckerDelta(x, y)) == "double(x == y)" assert mcode(KroneckerDelta(x, y + 1)) == "double(x == (y + 1))" assert mcode(KroneckerDelta(2**x, y)) == "double((2.^x) == y)" def test_Matrices(): assert mcode(Matrix(1, 1, [10])) == "10" A = Matrix([[1, sin(x/2), abs(x)], [0, 1, pi], [0, exp(1), ceiling(x)]]); expected = "[1 sin(x/2) abs(x); 0 1 pi; 0 exp(1) ceil(x)]" assert mcode(A) == expected # row and columns assert mcode(A[:,0]) == "[1; 0; 0]" assert mcode(A[0,:]) == "[1 sin(x/2) abs(x)]" # empty matrices assert mcode(Matrix(0, 0, [])) == '[]' assert mcode(Matrix(0, 3, [])) == 'zeros(0, 3)' # annoying to read but correct assert mcode(Matrix([[x, x - y, -y]])) == "[x x - y -y]" def test_vector_entries_hadamard(): # For a row or column, user might to use the other dimension A = Matrix([[1, sin(2/x), 3*pi/x/5]]) assert mcode(A) == "[1 sin(2./x) 3*pi./(5*x)]" assert mcode(A.T) == "[1; sin(2./x); 3*pi./(5*x)]" @XFAIL def test_Matrices_entries_not_hadamard(): # For Matrix with col >= 2, row >= 2, they need to be scalars # FIXME: is it worth worrying about this? Its not wrong, just # leave it user's responsibility to put scalar data for x. A = Matrix([[1, sin(2/x), 3*pi/x/5], [1, 2, x*y]]) expected = ("[1 sin(2/x) 3*pi/(5*x);\n" "1 2 x*y]") # <- we give x.*y assert mcode(A) == expected def test_MatrixSymbol(): n = Symbol('n', integer=True) A = MatrixSymbol('A', n, n) B = MatrixSymbol('B', n, n) assert mcode(A*B) == "A*B" assert mcode(B*A) == "B*A" assert mcode(2*A*B) == "2*A*B" assert mcode(B*2*A) == "2*B*A" assert mcode(A*(B + 3*Identity(n))) == "A*(3*eye(n) + B)" assert mcode(A**(x**2)) == "A^(x.^2)" assert mcode(A**3) == "A^3" assert mcode(A**S.Half) == "A^(1/2)" def test_MatrixSolve(): n = Symbol('n', integer=True) A = MatrixSymbol('A', n, n) x = MatrixSymbol('x', n, 1) assert mcode(MatrixSolve(A, x)) == "A \\ x" def test_special_matrices(): assert mcode(6*Identity(3)) == "6*eye(3)" def test_containers(): assert mcode([1, 2, 3, [4, 5, [6, 7]], 8, [9, 10], 11]) == \ "{1, 2, 3, {4, 5, {6, 7}}, 8, {9, 10}, 11}" assert mcode((1, 2, (3, 4))) == "{1, 2, {3, 4}}" assert mcode([1]) == "{1}" assert mcode((1,)) == "{1}" assert mcode(Tuple(*[1, 2, 3])) == "{1, 2, 3}" assert mcode((1, x*y, (3, x**2))) == "{1, x.*y, {3, x.^2}}" # scalar, matrix, empty matrix and empty list assert mcode((1, eye(3), Matrix(0, 0, []), [])) == "{1, [1 0 0; 0 1 0; 0 0 1], [], {}}" def test_octave_noninline(): source = mcode((x+y)/Catalan, assign_to='me', inline=False) expected = ( "Catalan = %s;\n" "me = (x + y)/Catalan;" ) % Catalan.evalf(17) assert source == expected def test_octave_piecewise(): expr = Piecewise((x, x < 1), (x**2, True)) assert mcode(expr) == "((x < 1).*(x) + (~(x < 1)).*(x.^2))" assert mcode(expr, assign_to="r") == ( "r = ((x < 1).*(x) + (~(x < 1)).*(x.^2));") assert mcode(expr, assign_to="r", inline=False) == ( "if (x < 1)\n" " r = x;\n" "else\n" " r = x.^2;\n" "end") expr = Piecewise((x**2, x < 1), (x**3, x < 2), (x**4, x < 3), (x**5, True)) expected = ("((x < 1).*(x.^2) + (~(x < 1)).*( ...\n" "(x < 2).*(x.^3) + (~(x < 2)).*( ...\n" "(x < 3).*(x.^4) + (~(x < 3)).*(x.^5))))") assert mcode(expr) == expected assert mcode(expr, assign_to="r") == "r = " + expected + ";" assert mcode(expr, assign_to="r", inline=False) == ( "if (x < 1)\n" " r = x.^2;\n" "elseif (x < 2)\n" " r = x.^3;\n" "elseif (x < 3)\n" " r = x.^4;\n" "else\n" " r = x.^5;\n" "end") # Check that Piecewise without a True (default) condition error expr = Piecewise((x, x < 1), (x**2, x > 1), (sin(x), x > 0)) raises(ValueError, lambda: mcode(expr)) def test_octave_piecewise_times_const(): pw = Piecewise((x, x < 1), (x**2, True)) assert mcode(2*pw) == "2*((x < 1).*(x) + (~(x < 1)).*(x.^2))" assert mcode(pw/x) == "((x < 1).*(x) + (~(x < 1)).*(x.^2))./x" assert mcode(pw/(x*y)) == "((x < 1).*(x) + (~(x < 1)).*(x.^2))./(x.*y)" assert mcode(pw/3) == "((x < 1).*(x) + (~(x < 1)).*(x.^2))/3" def test_octave_matrix_assign_to(): A = Matrix([[1, 2, 3]]) assert mcode(A, assign_to='a') == "a = [1 2 3];" A = Matrix([[1, 2], [3, 4]]) assert mcode(A, assign_to='A') == "A = [1 2; 3 4];" def test_octave_matrix_assign_to_more(): # assigning to Symbol or MatrixSymbol requires lhs/rhs match A = Matrix([[1, 2, 3]]) B = MatrixSymbol('B', 1, 3) C = MatrixSymbol('C', 2, 3) assert mcode(A, assign_to=B) == "B = [1 2 3];" raises(ValueError, lambda: mcode(A, assign_to=x)) raises(ValueError, lambda: mcode(A, assign_to=C)) def test_octave_matrix_1x1(): A = Matrix([[3]]) B = MatrixSymbol('B', 1, 1) C = MatrixSymbol('C', 1, 2) assert mcode(A, assign_to=B) == "B = 3;" # FIXME? #assert mcode(A, assign_to=x) == "x = 3;" raises(ValueError, lambda: mcode(A, assign_to=C)) def test_octave_matrix_elements(): A = Matrix([[x, 2, x*y]]) assert mcode(A[0, 0]**2 + A[0, 1] + A[0, 2]) == "x.^2 + x.*y + 2" A = MatrixSymbol('AA', 1, 3) assert mcode(A) == "AA" assert mcode(A[0, 0]**2 + sin(A[0,1]) + A[0,2]) == \ "sin(AA(1, 2)) + AA(1, 1).^2 + AA(1, 3)" assert mcode(sum(A)) == "AA(1, 1) + AA(1, 2) + AA(1, 3)" def test_octave_boolean(): assert mcode(True) == "true" assert mcode(S.true) == "true" assert mcode(False) == "false" assert mcode(S.false) == "false" def test_octave_not_supported(): assert mcode(S.ComplexInfinity) == ( "% Not supported in Octave:\n" "% ComplexInfinity\n" "zoo" ) f = Function('f') assert mcode(f(x).diff(x)) == ( "% Not supported in Octave:\n" "% Derivative\n" "Derivative(f(x), x)" ) def test_octave_not_supported_not_on_whitelist(): from sympy import assoc_laguerre assert mcode(assoc_laguerre(x, y, z)) == ( "% Not supported in Octave:\n" "% assoc_laguerre\n" "assoc_laguerre(x, y, z)" ) def test_octave_expint(): assert mcode(expint(1, x)) == "expint(x)" assert mcode(expint(2, x)) == ( "% Not supported in Octave:\n" "% expint\n" "expint(2, x)" ) assert mcode(expint(y, x)) == ( "% Not supported in Octave:\n" "% expint\n" "expint(y, x)" ) def test_trick_indent_with_end_else_words(): # words starting with "end" or "else" do not confuse the indenter t1 = S('endless'); t2 = S('elsewhere'); pw = Piecewise((t1, x < 0), (t2, x <= 1), (1, True)) assert mcode(pw, inline=False) == ( "if (x < 0)\n" " endless\n" "elseif (x <= 1)\n" " elsewhere\n" "else\n" " 1\n" "end") def test_hadamard(): A = MatrixSymbol('A', 3, 3) B = MatrixSymbol('B', 3, 3) v = MatrixSymbol('v', 3, 1) h = MatrixSymbol('h', 1, 3) C = HadamardProduct(A, B) n = Symbol('n') assert mcode(C) == "A.*B" assert mcode(C*v) == "(A.*B)*v" assert mcode(h*C*v) == "h*(A.*B)*v" assert mcode(C*A) == "(A.*B)*A" # mixing Hadamard and scalar strange b/c we vectorize scalars assert mcode(C*x*y) == "(x.*y)*(A.*B)" # Testing HadamardPower: assert mcode(HadamardPower(A, n)) == "A.**n" assert mcode(HadamardPower(A, 1+n)) == "A.**(n + 1)" assert mcode(HadamardPower(A*B.T, 1+n)) == "(A*B.T).**(n + 1)" def test_sparse(): M = SparseMatrix(5, 6, {}) M[2, 2] = 10; M[1, 2] = 20; M[1, 3] = 22; M[0, 3] = 30; M[3, 0] = x*y; assert mcode(M) == ( "sparse([4 2 3 1 2], [1 3 3 4 4], [x.*y 20 10 30 22], 5, 6)" ) def test_sinc(): assert mcode(sinc(x)) == 'sinc(x/pi)' assert mcode(sinc(x + 3)) == 'sinc((x + 3)/pi)' assert mcode(sinc(pi*(x + 3))) == 'sinc(x + 3)' def test_trigfun(): for f in (sin, cos, tan, cot, sec, csc, asin, acos, acot, atan, asec, acsc, sinh, cosh, tanh, coth, csch, sech, asinh, acosh, atanh, acoth, asech, acsch): assert octave_code(f(x) == f.__name__ + '(x)') def test_specfun(): n = Symbol('n') for f in [besselj, bessely, besseli, besselk]: assert octave_code(f(n, x)) == f.__name__ + '(n, x)' for f in (erfc, erfi, erf, erfinv, erfcinv, fresnelc, fresnels, gamma): assert octave_code(f(x)) == f.__name__ + '(x)' assert octave_code(hankel1(n, x)) == 'besselh(n, 1, x)' assert octave_code(hankel2(n, x)) == 'besselh(n, 2, x)' assert octave_code(airyai(x)) == 'airy(0, x)' assert octave_code(airyaiprime(x)) == 'airy(1, x)' assert octave_code(airybi(x)) == 'airy(2, x)' assert octave_code(airybiprime(x)) == 'airy(3, x)' assert octave_code(uppergamma(n, x)) == '(gammainc(x, n, \'upper\').*gamma(n))' assert octave_code(lowergamma(n, x)) == '(gammainc(x, n).*gamma(n))' assert octave_code(z**lowergamma(n, x)) == 'z.^(gammainc(x, n).*gamma(n))' assert octave_code(jn(n, x)) == 'sqrt(2)*sqrt(pi)*sqrt(1./x).*besselj(n + 1/2, x)/2' assert octave_code(yn(n, x)) == 'sqrt(2)*sqrt(pi)*sqrt(1./x).*bessely(n + 1/2, x)/2' assert octave_code(LambertW(x)) == 'lambertw(x)' assert octave_code(LambertW(x, n)) == 'lambertw(n, x)' def test_MatrixElement_printing(): # test cases for issue #11821 A = MatrixSymbol("A", 1, 3) B = MatrixSymbol("B", 1, 3) C = MatrixSymbol("C", 1, 3) assert mcode(A[0, 0]) == "A(1, 1)" assert mcode(3 * A[0, 0]) == "3*A(1, 1)" F = C[0, 0].subs(C, A - B) assert mcode(F) == "(A - B)(1, 1)" def test_zeta_printing_issue_14820(): assert octave_code(zeta(x)) == 'zeta(x)' assert octave_code(zeta(x, y)) == '% Not supported in Octave:\n% zeta\nzeta(x, y)' def test_automatic_rewrite(): assert octave_code(Li(x)) == 'logint(x) - logint(2)' assert octave_code(erf2(x, y)) == '-erf(x) + erf(y)'
9b0be096895974c34309a1b19a666bbbe735fa8a3f5d68ad8cf1662062d67ed6
from sympy.core import (pi, symbols, Rational, Integer, GoldenRatio, EulerGamma, Catalan, Lambda, Dummy, Eq, Ne, Le, Lt, Gt, Ge) from sympy.functions import Piecewise, sin, cos, Abs, exp, ceiling, sqrt from sympy.testing.pytest import raises, warns_deprecated_sympy from sympy.printing.glsl import GLSLPrinter from sympy.printing.str import StrPrinter from sympy.utilities.lambdify import implemented_function from sympy.tensor import IndexedBase, Idx from sympy.matrices import Matrix, MatrixSymbol from sympy.core import Tuple from sympy import glsl_code import textwrap x, y, z = symbols('x,y,z') def test_printmethod(): assert glsl_code(Abs(x)) == "abs(x)" def test_print_without_operators(): assert glsl_code(x*y,use_operators = False) == 'mul(x, y)' assert glsl_code(x**y+z,use_operators = False) == 'add(pow(x, y), z)' assert glsl_code(x*(y+z),use_operators = False) == 'mul(x, add(y, z))' assert glsl_code(x*(y+z),use_operators = False) == 'mul(x, add(y, z))' assert glsl_code(x*(y+z**y**0.5),use_operators = False) == 'mul(x, add(y, pow(z, sqrt(y))))' assert glsl_code(-x-y, use_operators=False, zero='zero()') == 'sub(zero(), add(x, y))' assert glsl_code(-x-y, use_operators=False) == 'sub(0.0, add(x, y))' def test_glsl_code_sqrt(): assert glsl_code(sqrt(x)) == "sqrt(x)" assert glsl_code(x**0.5) == "sqrt(x)" assert glsl_code(sqrt(x)) == "sqrt(x)" def test_glsl_code_Pow(): g = implemented_function('g', Lambda(x, 2*x)) assert glsl_code(x**3) == "pow(x, 3.0)" assert glsl_code(x**(y**3)) == "pow(x, pow(y, 3.0))" assert glsl_code(1/(g(x)*3.5)**(x - y**x)/(x**2 + y)) == \ "pow(3.5*2*x, -x + pow(y, x))/(pow(x, 2.0) + y)" assert glsl_code(x**-1.0) == '1.0/x' def test_glsl_code_Relational(): assert glsl_code(Eq(x, y)) == "x == y" assert glsl_code(Ne(x, y)) == "x != y" assert glsl_code(Le(x, y)) == "x <= y" assert glsl_code(Lt(x, y)) == "x < y" assert glsl_code(Gt(x, y)) == "x > y" assert glsl_code(Ge(x, y)) == "x >= y" def test_glsl_code_constants_mathh(): assert glsl_code(exp(1)) == "float E = 2.71828183;\nE" assert glsl_code(pi) == "float pi = 3.14159265;\npi" # assert glsl_code(oo) == "Number.POSITIVE_INFINITY" # assert glsl_code(-oo) == "Number.NEGATIVE_INFINITY" def test_glsl_code_constants_other(): assert glsl_code(2*GoldenRatio) == "float GoldenRatio = 1.61803399;\n2*GoldenRatio" assert glsl_code(2*Catalan) == "float Catalan = 0.915965594;\n2*Catalan" assert glsl_code(2*EulerGamma) == "float EulerGamma = 0.577215665;\n2*EulerGamma" def test_glsl_code_Rational(): assert glsl_code(Rational(3, 7)) == "3.0/7.0" assert glsl_code(Rational(18, 9)) == "2" assert glsl_code(Rational(3, -7)) == "-3.0/7.0" assert glsl_code(Rational(-3, -7)) == "3.0/7.0" def test_glsl_code_Integer(): assert glsl_code(Integer(67)) == "67" assert glsl_code(Integer(-1)) == "-1" def test_glsl_code_functions(): assert glsl_code(sin(x) ** cos(x)) == "pow(sin(x), cos(x))" def test_glsl_code_inline_function(): x = symbols('x') g = implemented_function('g', Lambda(x, 2*x)) assert glsl_code(g(x)) == "2*x" g = implemented_function('g', Lambda(x, 2*x/Catalan)) assert glsl_code(g(x)) == "float Catalan = 0.915965594;\n2*x/Catalan" A = IndexedBase('A') i = Idx('i', symbols('n', integer=True)) g = implemented_function('g', Lambda(x, x*(1 + x)*(2 + x))) assert glsl_code(g(A[i]), assign_to=A[i]) == ( "for (int i=0; i<n; i++){\n" " A[i] = (A[i] + 1)*(A[i] + 2)*A[i];\n" "}" ) def test_glsl_code_exceptions(): assert glsl_code(ceiling(x)) == "ceil(x)" assert glsl_code(Abs(x)) == "abs(x)" def test_glsl_code_boolean(): assert glsl_code(x & y) == "x && y" assert glsl_code(x | y) == "x || y" assert glsl_code(~x) == "!x" assert glsl_code(x & y & z) == "x && y && z" assert glsl_code(x | y | z) == "x || y || z" assert glsl_code((x & y) | z) == "z || x && y" assert glsl_code((x | y) & z) == "z && (x || y)" def test_glsl_code_Piecewise(): expr = Piecewise((x, x < 1), (x**2, True)) p = glsl_code(expr) s = \ """\ ((x < 1) ? ( x ) : ( pow(x, 2.0) ))\ """ assert p == s assert glsl_code(expr, assign_to="c") == ( "if (x < 1) {\n" " c = x;\n" "}\n" "else {\n" " c = pow(x, 2.0);\n" "}") # Check that Piecewise without a True (default) condition error expr = Piecewise((x, x < 1), (x**2, x > 1), (sin(x), x > 0)) raises(ValueError, lambda: glsl_code(expr)) def test_glsl_code_Piecewise_deep(): p = glsl_code(2*Piecewise((x, x < 1), (x**2, True))) s = \ """\ 2*((x < 1) ? ( x ) : ( pow(x, 2.0) ))\ """ assert p == s def test_glsl_code_settings(): raises(TypeError, lambda: glsl_code(sin(x), method="garbage")) def test_glsl_code_Indexed(): from sympy.tensor import IndexedBase, Idx from sympy import symbols n, m, o = symbols('n m o', integer=True) i, j, k = Idx('i', n), Idx('j', m), Idx('k', o) p = GLSLPrinter() p._not_c = set() x = IndexedBase('x')[j] assert p._print_Indexed(x) == 'x[j]' A = IndexedBase('A')[i, j] assert p._print_Indexed(A) == 'A[%s]' % (m*i+j) B = IndexedBase('B')[i, j, k] assert p._print_Indexed(B) == 'B[%s]' % (i*o*m+j*o+k) assert p._not_c == set() def test_glsl_code_list_tuple_Tuple(): assert glsl_code([1,2,3,4]) == 'vec4(1, 2, 3, 4)' assert glsl_code([1,2,3],glsl_types=False) == 'float[3](1, 2, 3)' assert glsl_code([1,2,3]) == glsl_code((1,2,3)) assert glsl_code([1,2,3]) == glsl_code(Tuple(1,2,3)) m = MatrixSymbol('A',3,4) assert glsl_code([m[0],m[1]]) def test_glsl_code_loops_matrix_vector(): n, m = symbols('n m', integer=True) A = IndexedBase('A') x = IndexedBase('x') y = IndexedBase('y') i = Idx('i', m) j = Idx('j', n) s = ( 'for (int i=0; i<m; i++){\n' ' y[i] = 0.0;\n' '}\n' 'for (int i=0; i<m; i++){\n' ' for (int j=0; j<n; j++){\n' ' y[i] = A[n*i + j]*x[j] + y[i];\n' ' }\n' '}' ) c = glsl_code(A[i, j]*x[j], assign_to=y[i]) assert c == s def test_dummy_loops(): i, m = symbols('i m', integer=True, cls=Dummy) x = IndexedBase('x') y = IndexedBase('y') i = Idx(i, m) expected = ( 'for (int i_%(icount)i=0; i_%(icount)i<m_%(mcount)i; i_%(icount)i++){\n' ' y[i_%(icount)i] = x[i_%(icount)i];\n' '}' ) % {'icount': i.label.dummy_index, 'mcount': m.dummy_index} code = glsl_code(x[i], assign_to=y[i]) assert code == expected def test_glsl_code_loops_add(): from sympy.tensor import IndexedBase, Idx from sympy import symbols n, m = symbols('n m', integer=True) A = IndexedBase('A') x = IndexedBase('x') y = IndexedBase('y') z = IndexedBase('z') i = Idx('i', m) j = Idx('j', n) s = ( 'for (int i=0; i<m; i++){\n' ' y[i] = x[i] + z[i];\n' '}\n' 'for (int i=0; i<m; i++){\n' ' for (int j=0; j<n; j++){\n' ' y[i] = A[n*i + j]*x[j] + y[i];\n' ' }\n' '}' ) c = glsl_code(A[i, j]*x[j] + x[i] + z[i], assign_to=y[i]) assert c == s def test_glsl_code_loops_multiple_contractions(): from sympy.tensor import IndexedBase, Idx from sympy import symbols n, m, o, p = symbols('n m o p', integer=True) a = IndexedBase('a') b = IndexedBase('b') y = IndexedBase('y') i = Idx('i', m) j = Idx('j', n) k = Idx('k', o) l = Idx('l', p) s = ( 'for (int i=0; i<m; i++){\n' ' y[i] = 0.0;\n' '}\n' 'for (int i=0; i<m; i++){\n' ' for (int j=0; j<n; j++){\n' ' for (int k=0; k<o; k++){\n' ' for (int l=0; l<p; l++){\n' ' y[i] = a[%s]*b[%s] + y[i];\n' % (i*n*o*p + j*o*p + k*p + l, j*o*p + k*p + l) +\ ' }\n' ' }\n' ' }\n' '}' ) c = glsl_code(b[j, k, l]*a[i, j, k, l], assign_to=y[i]) assert c == s def test_glsl_code_loops_addfactor(): from sympy.tensor import IndexedBase, Idx from sympy import symbols n, m, o, p = symbols('n m o p', integer=True) a = IndexedBase('a') b = IndexedBase('b') c = IndexedBase('c') y = IndexedBase('y') i = Idx('i', m) j = Idx('j', n) k = Idx('k', o) l = Idx('l', p) s = ( 'for (int i=0; i<m; i++){\n' ' y[i] = 0.0;\n' '}\n' 'for (int i=0; i<m; i++){\n' ' for (int j=0; j<n; j++){\n' ' for (int k=0; k<o; k++){\n' ' for (int l=0; l<p; l++){\n' ' y[i] = (a[%s] + b[%s])*c[%s] + y[i];\n' % (i*n*o*p + j*o*p + k*p + l, i*n*o*p + j*o*p + k*p + l, j*o*p + k*p + l) +\ ' }\n' ' }\n' ' }\n' '}' ) c = glsl_code((a[i, j, k, l] + b[i, j, k, l])*c[j, k, l], assign_to=y[i]) assert c == s def test_glsl_code_loops_multiple_terms(): from sympy.tensor import IndexedBase, Idx from sympy import symbols n, m, o, p = symbols('n m o p', integer=True) a = IndexedBase('a') b = IndexedBase('b') c = IndexedBase('c') y = IndexedBase('y') i = Idx('i', m) j = Idx('j', n) k = Idx('k', o) s0 = ( 'for (int i=0; i<m; i++){\n' ' y[i] = 0.0;\n' '}\n' ) s1 = ( 'for (int i=0; i<m; i++){\n' ' for (int j=0; j<n; j++){\n' ' for (int k=0; k<o; k++){\n' ' y[i] = b[j]*b[k]*c[%s] + y[i];\n' % (i*n*o + j*o + k) +\ ' }\n' ' }\n' '}\n' ) s2 = ( 'for (int i=0; i<m; i++){\n' ' for (int k=0; k<o; k++){\n' ' y[i] = a[%s]*b[k] + y[i];\n' % (i*o + k) +\ ' }\n' '}\n' ) s3 = ( 'for (int i=0; i<m; i++){\n' ' for (int j=0; j<n; j++){\n' ' y[i] = a[%s]*b[j] + y[i];\n' % (i*n + j) +\ ' }\n' '}\n' ) c = glsl_code( b[j]*a[i, j] + b[k]*a[i, k] + b[j]*b[k]*c[i, j, k], assign_to=y[i]) assert (c == s0 + s1 + s2 + s3[:-1] or c == s0 + s1 + s3 + s2[:-1] or c == s0 + s2 + s1 + s3[:-1] or c == s0 + s2 + s3 + s1[:-1] or c == s0 + s3 + s1 + s2[:-1] or c == s0 + s3 + s2 + s1[:-1]) def test_Matrix_printing(): # Test returning a Matrix mat = Matrix([x*y, Piecewise((2 + x, y>0), (y, True)), sin(z)]) A = MatrixSymbol('A', 3, 1) assert glsl_code(mat, assign_to=A) == ( '''A[0][0] = x*y; if (y > 0) { A[1][0] = x + 2; } else { A[1][0] = y; } A[2][0] = sin(z);''' ) assert glsl_code(Matrix([A[0],A[1]])) # Test using MatrixElements in expressions expr = Piecewise((2*A[2, 0], x > 0), (A[2, 0], True)) + sin(A[1, 0]) + A[0, 0] assert glsl_code(expr) == ( '''((x > 0) ? ( 2*A[2][0] ) : ( A[2][0] )) + sin(A[1][0]) + A[0][0]''' ) # Test using MatrixElements in a Matrix q = MatrixSymbol('q', 5, 1) M = MatrixSymbol('M', 3, 3) m = Matrix([[sin(q[1,0]), 0, cos(q[2,0])], [q[1,0] + q[2,0], q[3, 0], 5], [2*q[4, 0]/q[1,0], sqrt(q[0,0]) + 4, 0]]) assert glsl_code(m,M) == ( '''M[0][0] = sin(q[1]); M[0][1] = 0; M[0][2] = cos(q[2]); M[1][0] = q[1] + q[2]; M[1][1] = q[3]; M[1][2] = 5; M[2][0] = 2*q[4]/q[1]; M[2][1] = sqrt(q[0]) + 4; M[2][2] = 0;''' ) def test_Matrices_1x7(): gl = glsl_code A = Matrix([1,2,3,4,5,6,7]) assert gl(A) == 'float[7](1, 2, 3, 4, 5, 6, 7)' assert gl(A.transpose()) == 'float[7](1, 2, 3, 4, 5, 6, 7)' def test_Matrices_1x7_array_type_int(): gl = glsl_code A = Matrix([1,2,3,4,5,6,7]) assert gl(A, array_type='int') == 'int[7](1, 2, 3, 4, 5, 6, 7)' def test_Tuple_array_type_custom(): gl = glsl_code A = symbols('a b c') assert gl(A, array_type='AbcType', glsl_types=False) == 'AbcType[3](a, b, c)' def test_Matrices_1x7_spread_assign_to_symbols(): gl = glsl_code A = Matrix([1,2,3,4,5,6,7]) assign_to = symbols('x.a x.b x.c x.d x.e x.f x.g') assert gl(A, assign_to=assign_to) == textwrap.dedent('''\ x.a = 1; x.b = 2; x.c = 3; x.d = 4; x.e = 5; x.f = 6; x.g = 7;''' ) def test_spread_assign_to_nested_symbols(): gl = glsl_code expr = ((1,2,3), (1,2,3)) assign_to = (symbols('a b c'), symbols('x y z')) assert gl(expr, assign_to=assign_to) == textwrap.dedent('''\ a = 1; b = 2; c = 3; x = 1; y = 2; z = 3;''' ) def test_spread_assign_to_deeply_nested_symbols(): gl = glsl_code a, b, c, x, y, z = symbols('a b c x y z') expr = (((1,2),3), ((1,2),3)) assign_to = (((a, b), c), ((x, y), z)) assert gl(expr, assign_to=assign_to) == textwrap.dedent('''\ a = 1; b = 2; c = 3; x = 1; y = 2; z = 3;''' ) def test_matrix_of_tuples_spread_assign_to_symbols(): gl = glsl_code with warns_deprecated_sympy(): expr = Matrix([[(1,2),(3,4)],[(5,6),(7,8)]]) assign_to = (symbols('a b'), symbols('c d'), symbols('e f'), symbols('g h')) assert gl(expr, assign_to) == textwrap.dedent('''\ a = 1; b = 2; c = 3; d = 4; e = 5; f = 6; g = 7; h = 8;''' ) def test_cannot_assign_to_cause_mismatched_length(): expr = (1, 2) assign_to = symbols('x y z') raises(ValueError, lambda: glsl_code(expr, assign_to)) def test_matrix_4x4_assign(): gl = glsl_code expr = MatrixSymbol('A',4,4) * MatrixSymbol('B',4,4) + MatrixSymbol('C',4,4) assign_to = MatrixSymbol('X',4,4) assert gl(expr, assign_to=assign_to) == textwrap.dedent('''\ X[0][0] = A[0][0]*B[0][0] + A[0][1]*B[1][0] + A[0][2]*B[2][0] + A[0][3]*B[3][0] + C[0][0]; X[0][1] = A[0][0]*B[0][1] + A[0][1]*B[1][1] + A[0][2]*B[2][1] + A[0][3]*B[3][1] + C[0][1]; X[0][2] = A[0][0]*B[0][2] + A[0][1]*B[1][2] + A[0][2]*B[2][2] + A[0][3]*B[3][2] + C[0][2]; X[0][3] = A[0][0]*B[0][3] + A[0][1]*B[1][3] + A[0][2]*B[2][3] + A[0][3]*B[3][3] + C[0][3]; X[1][0] = A[1][0]*B[0][0] + A[1][1]*B[1][0] + A[1][2]*B[2][0] + A[1][3]*B[3][0] + C[1][0]; X[1][1] = A[1][0]*B[0][1] + A[1][1]*B[1][1] + A[1][2]*B[2][1] + A[1][3]*B[3][1] + C[1][1]; X[1][2] = A[1][0]*B[0][2] + A[1][1]*B[1][2] + A[1][2]*B[2][2] + A[1][3]*B[3][2] + C[1][2]; X[1][3] = A[1][0]*B[0][3] + A[1][1]*B[1][3] + A[1][2]*B[2][3] + A[1][3]*B[3][3] + C[1][3]; X[2][0] = A[2][0]*B[0][0] + A[2][1]*B[1][0] + A[2][2]*B[2][0] + A[2][3]*B[3][0] + C[2][0]; X[2][1] = A[2][0]*B[0][1] + A[2][1]*B[1][1] + A[2][2]*B[2][1] + A[2][3]*B[3][1] + C[2][1]; X[2][2] = A[2][0]*B[0][2] + A[2][1]*B[1][2] + A[2][2]*B[2][2] + A[2][3]*B[3][2] + C[2][2]; X[2][3] = A[2][0]*B[0][3] + A[2][1]*B[1][3] + A[2][2]*B[2][3] + A[2][3]*B[3][3] + C[2][3]; X[3][0] = A[3][0]*B[0][0] + A[3][1]*B[1][0] + A[3][2]*B[2][0] + A[3][3]*B[3][0] + C[3][0]; X[3][1] = A[3][0]*B[0][1] + A[3][1]*B[1][1] + A[3][2]*B[2][1] + A[3][3]*B[3][1] + C[3][1]; X[3][2] = A[3][0]*B[0][2] + A[3][1]*B[1][2] + A[3][2]*B[2][2] + A[3][3]*B[3][2] + C[3][2]; X[3][3] = A[3][0]*B[0][3] + A[3][1]*B[1][3] + A[3][2]*B[2][3] + A[3][3]*B[3][3] + C[3][3];''' ) def test_1xN_vecs(): gl = glsl_code for i in range(1,10): A = Matrix(range(i)) assert gl(A.transpose()) == gl(A) assert gl(A,mat_transpose=True) == gl(A) if i > 1: if i <= 4: assert gl(A) == 'vec%s(%s)' % (i,', '.join(str(s) for s in range(i))) else: assert gl(A) == 'float[%s](%s)' % (i,', '.join(str(s) for s in range(i))) def test_MxN_mats(): generatedAssertions='def test_misc_mats():\n' for i in range(1,6): for j in range(1,6): A = Matrix([[x + y*j for x in range(j)] for y in range(i)]) gl = glsl_code(A) glTransposed = glsl_code(A,mat_transpose=True) generatedAssertions+=' mat = '+StrPrinter()._print(A)+'\n\n' generatedAssertions+=' gl = \'\'\''+gl+'\'\'\'\n' generatedAssertions+=' glTransposed = \'\'\''+glTransposed+'\'\'\'\n\n' generatedAssertions+=' assert glsl_code(mat) == gl\n' generatedAssertions+=' assert glsl_code(mat,mat_transpose=True) == glTransposed\n' if i == 1 and j == 1: assert gl == '0' elif i <= 4 and j <= 4 and i>1 and j>1: assert gl.startswith('mat%s' % j) assert glTransposed.startswith('mat%s' % i) elif i == 1 and j <= 4: assert gl.startswith('vec') elif j == 1 and i <= 4: assert gl.startswith('vec') elif i == 1: assert gl.startswith('float[%s]('% j*i) assert glTransposed.startswith('float[%s]('% j*i) elif j == 1: assert gl.startswith('float[%s]('% i*j) assert glTransposed.startswith('float[%s]('% i*j) else: assert gl.startswith('float[%s](' % (i*j)) assert glTransposed.startswith('float[%s](' % (i*j)) glNested = glsl_code(A,mat_nested=True) glNestedTransposed = glsl_code(A,mat_transpose=True,mat_nested=True) assert glNested.startswith('float[%s][%s]' % (i,j)) assert glNestedTransposed.startswith('float[%s][%s]' % (j,i)) generatedAssertions+=' glNested = \'\'\''+glNested+'\'\'\'\n' generatedAssertions+=' glNestedTransposed = \'\'\''+glNestedTransposed+'\'\'\'\n\n' generatedAssertions+=' assert glsl_code(mat,mat_nested=True) == glNested\n' generatedAssertions+=' assert glsl_code(mat,mat_nested=True,mat_transpose=True) == glNestedTransposed\n\n' generateAssertions = False # set this to true to write bake these generated tests to a file if generateAssertions: gen = open('test_glsl_generated_matrices.py','w') gen.write(generatedAssertions) gen.close() # these assertions were generated from the previous function # glsl has complicated rules and this makes it easier to look over all the cases def test_misc_mats(): mat = Matrix([[0]]) gl = '''0''' glTransposed = '''0''' assert glsl_code(mat) == gl assert glsl_code(mat,mat_transpose=True) == glTransposed mat = Matrix([[0, 1]]) gl = '''vec2(0, 1)''' glTransposed = '''vec2(0, 1)''' assert glsl_code(mat) == gl assert glsl_code(mat,mat_transpose=True) == glTransposed mat = Matrix([[0, 1, 2]]) gl = '''vec3(0, 1, 2)''' glTransposed = '''vec3(0, 1, 2)''' assert glsl_code(mat) == gl assert glsl_code(mat,mat_transpose=True) == glTransposed mat = Matrix([[0, 1, 2, 3]]) gl = '''vec4(0, 1, 2, 3)''' glTransposed = '''vec4(0, 1, 2, 3)''' assert glsl_code(mat) == gl assert glsl_code(mat,mat_transpose=True) == glTransposed mat = Matrix([[0, 1, 2, 3, 4]]) gl = '''float[5](0, 1, 2, 3, 4)''' glTransposed = '''float[5](0, 1, 2, 3, 4)''' assert glsl_code(mat) == gl assert glsl_code(mat,mat_transpose=True) == glTransposed mat = Matrix([ [0], [1]]) gl = '''vec2(0, 1)''' glTransposed = '''vec2(0, 1)''' assert glsl_code(mat) == gl assert glsl_code(mat,mat_transpose=True) == glTransposed mat = Matrix([ [0, 1], [2, 3]]) gl = '''mat2(0, 1, 2, 3)''' glTransposed = '''mat2(0, 2, 1, 3)''' assert glsl_code(mat) == gl assert glsl_code(mat,mat_transpose=True) == glTransposed mat = Matrix([ [0, 1, 2], [3, 4, 5]]) gl = '''mat3x2(0, 1, 2, 3, 4, 5)''' glTransposed = '''mat2x3(0, 3, 1, 4, 2, 5)''' assert glsl_code(mat) == gl assert glsl_code(mat,mat_transpose=True) == glTransposed mat = Matrix([ [0, 1, 2, 3], [4, 5, 6, 7]]) gl = '''mat4x2(0, 1, 2, 3, 4, 5, 6, 7)''' glTransposed = '''mat2x4(0, 4, 1, 5, 2, 6, 3, 7)''' assert glsl_code(mat) == gl assert glsl_code(mat,mat_transpose=True) == glTransposed mat = Matrix([ [0, 1, 2, 3, 4], [5, 6, 7, 8, 9]]) gl = '''float[10]( 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 ) /* a 2x5 matrix */''' glTransposed = '''float[10]( 0, 5, 1, 6, 2, 7, 3, 8, 4, 9 ) /* a 5x2 matrix */''' assert glsl_code(mat) == gl assert glsl_code(mat,mat_transpose=True) == glTransposed glNested = '''float[2][5]( float[](0, 1, 2, 3, 4), float[](5, 6, 7, 8, 9) )''' glNestedTransposed = '''float[5][2]( float[](0, 5), float[](1, 6), float[](2, 7), float[](3, 8), float[](4, 9) )''' assert glsl_code(mat,mat_nested=True) == glNested assert glsl_code(mat,mat_nested=True,mat_transpose=True) == glNestedTransposed mat = Matrix([ [0], [1], [2]]) gl = '''vec3(0, 1, 2)''' glTransposed = '''vec3(0, 1, 2)''' assert glsl_code(mat) == gl assert glsl_code(mat,mat_transpose=True) == glTransposed mat = Matrix([ [0, 1], [2, 3], [4, 5]]) gl = '''mat2x3(0, 1, 2, 3, 4, 5)''' glTransposed = '''mat3x2(0, 2, 4, 1, 3, 5)''' assert glsl_code(mat) == gl assert glsl_code(mat,mat_transpose=True) == glTransposed mat = Matrix([ [0, 1, 2], [3, 4, 5], [6, 7, 8]]) gl = '''mat3(0, 1, 2, 3, 4, 5, 6, 7, 8)''' glTransposed = '''mat3(0, 3, 6, 1, 4, 7, 2, 5, 8)''' assert glsl_code(mat) == gl assert glsl_code(mat,mat_transpose=True) == glTransposed mat = Matrix([ [0, 1, 2, 3], [4, 5, 6, 7], [8, 9, 10, 11]]) gl = '''mat4x3(0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11)''' glTransposed = '''mat3x4(0, 4, 8, 1, 5, 9, 2, 6, 10, 3, 7, 11)''' assert glsl_code(mat) == gl assert glsl_code(mat,mat_transpose=True) == glTransposed mat = Matrix([ [ 0, 1, 2, 3, 4], [ 5, 6, 7, 8, 9], [10, 11, 12, 13, 14]]) gl = '''float[15]( 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14 ) /* a 3x5 matrix */''' glTransposed = '''float[15]( 0, 5, 10, 1, 6, 11, 2, 7, 12, 3, 8, 13, 4, 9, 14 ) /* a 5x3 matrix */''' assert glsl_code(mat) == gl assert glsl_code(mat,mat_transpose=True) == glTransposed glNested = '''float[3][5]( float[]( 0, 1, 2, 3, 4), float[]( 5, 6, 7, 8, 9), float[](10, 11, 12, 13, 14) )''' glNestedTransposed = '''float[5][3]( float[](0, 5, 10), float[](1, 6, 11), float[](2, 7, 12), float[](3, 8, 13), float[](4, 9, 14) )''' assert glsl_code(mat,mat_nested=True) == glNested assert glsl_code(mat,mat_nested=True,mat_transpose=True) == glNestedTransposed mat = Matrix([ [0], [1], [2], [3]]) gl = '''vec4(0, 1, 2, 3)''' glTransposed = '''vec4(0, 1, 2, 3)''' assert glsl_code(mat) == gl assert glsl_code(mat,mat_transpose=True) == glTransposed mat = Matrix([ [0, 1], [2, 3], [4, 5], [6, 7]]) gl = '''mat2x4(0, 1, 2, 3, 4, 5, 6, 7)''' glTransposed = '''mat4x2(0, 2, 4, 6, 1, 3, 5, 7)''' assert glsl_code(mat) == gl assert glsl_code(mat,mat_transpose=True) == glTransposed mat = Matrix([ [0, 1, 2], [3, 4, 5], [6, 7, 8], [9, 10, 11]]) gl = '''mat3x4(0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11)''' glTransposed = '''mat4x3(0, 3, 6, 9, 1, 4, 7, 10, 2, 5, 8, 11)''' assert glsl_code(mat) == gl assert glsl_code(mat,mat_transpose=True) == glTransposed mat = Matrix([ [ 0, 1, 2, 3], [ 4, 5, 6, 7], [ 8, 9, 10, 11], [12, 13, 14, 15]]) gl = '''mat4( 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15)''' glTransposed = '''mat4(0, 4, 8, 12, 1, 5, 9, 13, 2, 6, 10, 14, 3, 7, 11, 15)''' assert glsl_code(mat) == gl assert glsl_code(mat,mat_transpose=True) == glTransposed mat = Matrix([ [ 0, 1, 2, 3, 4], [ 5, 6, 7, 8, 9], [10, 11, 12, 13, 14], [15, 16, 17, 18, 19]]) gl = '''float[20]( 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 ) /* a 4x5 matrix */''' glTransposed = '''float[20]( 0, 5, 10, 15, 1, 6, 11, 16, 2, 7, 12, 17, 3, 8, 13, 18, 4, 9, 14, 19 ) /* a 5x4 matrix */''' assert glsl_code(mat) == gl assert glsl_code(mat,mat_transpose=True) == glTransposed glNested = '''float[4][5]( float[]( 0, 1, 2, 3, 4), float[]( 5, 6, 7, 8, 9), float[](10, 11, 12, 13, 14), float[](15, 16, 17, 18, 19) )''' glNestedTransposed = '''float[5][4]( float[](0, 5, 10, 15), float[](1, 6, 11, 16), float[](2, 7, 12, 17), float[](3, 8, 13, 18), float[](4, 9, 14, 19) )''' assert glsl_code(mat,mat_nested=True) == glNested assert glsl_code(mat,mat_nested=True,mat_transpose=True) == glNestedTransposed mat = Matrix([ [0], [1], [2], [3], [4]]) gl = '''float[5](0, 1, 2, 3, 4)''' glTransposed = '''float[5](0, 1, 2, 3, 4)''' assert glsl_code(mat) == gl assert glsl_code(mat,mat_transpose=True) == glTransposed mat = Matrix([ [0, 1], [2, 3], [4, 5], [6, 7], [8, 9]]) gl = '''float[10]( 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 ) /* a 5x2 matrix */''' glTransposed = '''float[10]( 0, 2, 4, 6, 8, 1, 3, 5, 7, 9 ) /* a 2x5 matrix */''' assert glsl_code(mat) == gl assert glsl_code(mat,mat_transpose=True) == glTransposed glNested = '''float[5][2]( float[](0, 1), float[](2, 3), float[](4, 5), float[](6, 7), float[](8, 9) )''' glNestedTransposed = '''float[2][5]( float[](0, 2, 4, 6, 8), float[](1, 3, 5, 7, 9) )''' assert glsl_code(mat,mat_nested=True) == glNested assert glsl_code(mat,mat_nested=True,mat_transpose=True) == glNestedTransposed mat = Matrix([ [ 0, 1, 2], [ 3, 4, 5], [ 6, 7, 8], [ 9, 10, 11], [12, 13, 14]]) gl = '''float[15]( 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14 ) /* a 5x3 matrix */''' glTransposed = '''float[15]( 0, 3, 6, 9, 12, 1, 4, 7, 10, 13, 2, 5, 8, 11, 14 ) /* a 3x5 matrix */''' assert glsl_code(mat) == gl assert glsl_code(mat,mat_transpose=True) == glTransposed glNested = '''float[5][3]( float[]( 0, 1, 2), float[]( 3, 4, 5), float[]( 6, 7, 8), float[]( 9, 10, 11), float[](12, 13, 14) )''' glNestedTransposed = '''float[3][5]( float[](0, 3, 6, 9, 12), float[](1, 4, 7, 10, 13), float[](2, 5, 8, 11, 14) )''' assert glsl_code(mat,mat_nested=True) == glNested assert glsl_code(mat,mat_nested=True,mat_transpose=True) == glNestedTransposed mat = Matrix([ [ 0, 1, 2, 3], [ 4, 5, 6, 7], [ 8, 9, 10, 11], [12, 13, 14, 15], [16, 17, 18, 19]]) gl = '''float[20]( 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 ) /* a 5x4 matrix */''' glTransposed = '''float[20]( 0, 4, 8, 12, 16, 1, 5, 9, 13, 17, 2, 6, 10, 14, 18, 3, 7, 11, 15, 19 ) /* a 4x5 matrix */''' assert glsl_code(mat) == gl assert glsl_code(mat,mat_transpose=True) == glTransposed glNested = '''float[5][4]( float[]( 0, 1, 2, 3), float[]( 4, 5, 6, 7), float[]( 8, 9, 10, 11), float[](12, 13, 14, 15), float[](16, 17, 18, 19) )''' glNestedTransposed = '''float[4][5]( float[](0, 4, 8, 12, 16), float[](1, 5, 9, 13, 17), float[](2, 6, 10, 14, 18), float[](3, 7, 11, 15, 19) )''' assert glsl_code(mat,mat_nested=True) == glNested assert glsl_code(mat,mat_nested=True,mat_transpose=True) == glNestedTransposed mat = Matrix([ [ 0, 1, 2, 3, 4], [ 5, 6, 7, 8, 9], [10, 11, 12, 13, 14], [15, 16, 17, 18, 19], [20, 21, 22, 23, 24]]) gl = '''float[25]( 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24 ) /* a 5x5 matrix */''' glTransposed = '''float[25]( 0, 5, 10, 15, 20, 1, 6, 11, 16, 21, 2, 7, 12, 17, 22, 3, 8, 13, 18, 23, 4, 9, 14, 19, 24 ) /* a 5x5 matrix */''' assert glsl_code(mat) == gl assert glsl_code(mat,mat_transpose=True) == glTransposed glNested = '''float[5][5]( float[]( 0, 1, 2, 3, 4), float[]( 5, 6, 7, 8, 9), float[](10, 11, 12, 13, 14), float[](15, 16, 17, 18, 19), float[](20, 21, 22, 23, 24) )''' glNestedTransposed = '''float[5][5]( float[](0, 5, 10, 15, 20), float[](1, 6, 11, 16, 21), float[](2, 7, 12, 17, 22), float[](3, 8, 13, 18, 23), float[](4, 9, 14, 19, 24) )''' assert glsl_code(mat,mat_nested=True) == glNested assert glsl_code(mat,mat_nested=True,mat_transpose=True) == glNestedTransposed
d839e6a297d7cf9ba3fe1083dcb4e615e41d2d70cf1d927789f8074d6ea103e2
from sympy import Rational, sqrt, symbols, sin, exp, log, sinh, cosh, cos, pi, \ I, erf, tan, asin, asinh, acos, atan, Function, Derivative, diff, simplify, \ LambertW, Ne, Piecewise, Symbol, Add, ratsimp, Integral, Sum, \ besselj, besselk, bessely, jn, tanh from sympy.integrals.heurisch import components, heurisch, heurisch_wrapper from sympy.testing.pytest import XFAIL, skip, slow, ON_TRAVIS from sympy.integrals.integrals import integrate x, y, z, nu = symbols('x,y,z,nu') f = Function('f') def test_components(): assert components(x*y, x) == {x} assert components(1/(x + y), x) == {x} assert components(sin(x), x) == {sin(x), x} assert components(sin(x)*sqrt(log(x)), x) == \ {log(x), sin(x), sqrt(log(x)), x} assert components(x*sin(exp(x)*y), x) == \ {sin(y*exp(x)), x, exp(x)} assert components(x**Rational(17, 54)/sqrt(sin(x)), x) == \ {sin(x), x**Rational(1, 54), sqrt(sin(x)), x} assert components(f(x), x) == \ {x, f(x)} assert components(Derivative(f(x), x), x) == \ {x, f(x), Derivative(f(x), x)} assert components(f(x)*diff(f(x), x), x) == \ {x, f(x), Derivative(f(x), x), Derivative(f(x), x)} def test_issue_10680(): assert isinstance(integrate(x**log(x**log(x**log(x))),x), Integral) def test_issue_21166(): assert integrate(sin(x/sqrt(abs(x))), (x, -1, 1)) == 0 def test_heurisch_polynomials(): assert heurisch(1, x) == x assert heurisch(x, x) == x**2/2 assert heurisch(x**17, x) == x**18/18 # For coverage assert heurisch_wrapper(y, x) == y*x def test_heurisch_fractions(): assert heurisch(1/x, x) == log(x) assert heurisch(1/(2 + x), x) == log(x + 2) assert heurisch(1/(x + sin(y)), x) == log(x + sin(y)) # Up to a constant, where C = pi*I*Rational(5, 12), Mathematica gives identical # result in the first case. The difference is because sympy changes # signs of expressions without any care. # XXX ^ ^ ^ is this still correct? assert heurisch(5*x**5/( 2*x**6 - 5), x) in [5*log(2*x**6 - 5) / 12, 5*log(-2*x**6 + 5) / 12] assert heurisch(5*x**5/(2*x**6 + 5), x) == 5*log(2*x**6 + 5) / 12 assert heurisch(1/x**2, x) == -1/x assert heurisch(-1/x**5, x) == 1/(4*x**4) def test_heurisch_log(): assert heurisch(log(x), x) == x*log(x) - x assert heurisch(log(3*x), x) == -x + x*log(3) + x*log(x) assert heurisch(log(x**2), x) in [x*log(x**2) - 2*x, 2*x*log(x) - 2*x] def test_heurisch_exp(): assert heurisch(exp(x), x) == exp(x) assert heurisch(exp(-x), x) == -exp(-x) assert heurisch(exp(17*x), x) == exp(17*x) / 17 assert heurisch(x*exp(x), x) == x*exp(x) - exp(x) assert heurisch(x*exp(x**2), x) == exp(x**2) / 2 assert heurisch(exp(-x**2), x) is None assert heurisch(2**x, x) == 2**x/log(2) assert heurisch(x*2**x, x) == x*2**x/log(2) - 2**x*log(2)**(-2) assert heurisch(Integral(x**z*y, (y, 1, 2), (z, 2, 3)).function, x) == (x*x**z*y)/(z+1) assert heurisch(Sum(x**z, (z, 1, 2)).function, z) == x**z/log(x) def test_heurisch_trigonometric(): assert heurisch(sin(x), x) == -cos(x) assert heurisch(pi*sin(x) + 1, x) == x - pi*cos(x) assert heurisch(cos(x), x) == sin(x) assert heurisch(tan(x), x) in [ log(1 + tan(x)**2)/2, log(tan(x) + I) + I*x, log(tan(x) - I) - I*x, ] assert heurisch(sin(x)*sin(y), x) == -cos(x)*sin(y) assert heurisch(sin(x)*sin(y), y) == -cos(y)*sin(x) # gives sin(x) in answer when run via setup.py and cos(x) when run via py.test assert heurisch(sin(x)*cos(x), x) in [sin(x)**2 / 2, -cos(x)**2 / 2] assert heurisch(cos(x)/sin(x), x) == log(sin(x)) assert heurisch(x*sin(7*x), x) == sin(7*x) / 49 - x*cos(7*x) / 7 assert heurisch(1/pi/4 * x**2*cos(x), x) == 1/pi/4*(x**2*sin(x) - 2*sin(x) + 2*x*cos(x)) assert heurisch(acos(x/4) * asin(x/4), x) == 2*x - (sqrt(16 - x**2))*asin(x/4) \ + (sqrt(16 - x**2))*acos(x/4) + x*asin(x/4)*acos(x/4) assert heurisch(sin(x)/(cos(x)**2+1), x) == -atan(cos(x)) #fixes issue 13723 assert heurisch(1/(cos(x)+2), x) == 2*sqrt(3)*atan(sqrt(3)*tan(x/2)/3)/3 assert heurisch(2*sin(x)*cos(x)/(sin(x)**4 + 1), x) == atan(sqrt(2)*sin(x) - 1) - atan(sqrt(2)*sin(x) + 1) assert heurisch(1/cosh(x), x) == 2*atan(tanh(x/2)) def test_heurisch_hyperbolic(): assert heurisch(sinh(x), x) == cosh(x) assert heurisch(cosh(x), x) == sinh(x) assert heurisch(x*sinh(x), x) == x*cosh(x) - sinh(x) assert heurisch(x*cosh(x), x) == x*sinh(x) - cosh(x) assert heurisch( x*asinh(x/2), x) == x**2*asinh(x/2)/2 + asinh(x/2) - x*sqrt(4 + x**2)/4 def test_heurisch_mixed(): assert heurisch(sin(x)*exp(x), x) == exp(x)*sin(x)/2 - exp(x)*cos(x)/2 assert heurisch(sin(x/sqrt(-x)), x) == 2*x*cos(x/sqrt(-x))/sqrt(-x) - 2*sin(x/sqrt(-x)) def test_heurisch_radicals(): assert heurisch(1/sqrt(x), x) == 2*sqrt(x) assert heurisch(1/sqrt(x)**3, x) == -2/sqrt(x) assert heurisch(sqrt(x)**3, x) == 2*sqrt(x)**5/5 assert heurisch(sin(x)*sqrt(cos(x)), x) == -2*sqrt(cos(x))**3/3 y = Symbol('y') assert heurisch(sin(y*sqrt(x)), x) == 2/y**2*sin(y*sqrt(x)) - \ 2*sqrt(x)*cos(y*sqrt(x))/y assert heurisch_wrapper(sin(y*sqrt(x)), x) == Piecewise( (-2*sqrt(x)*cos(sqrt(x)*y)/y + 2*sin(sqrt(x)*y)/y**2, Ne(y, 0)), (0, True)) y = Symbol('y', positive=True) assert heurisch_wrapper(sin(y*sqrt(x)), x) == 2/y**2*sin(y*sqrt(x)) - \ 2*sqrt(x)*cos(y*sqrt(x))/y def test_heurisch_special(): assert heurisch(erf(x), x) == x*erf(x) + exp(-x**2)/sqrt(pi) assert heurisch(exp(-x**2)*erf(x), x) == sqrt(pi)*erf(x)**2 / 4 def test_heurisch_symbolic_coeffs(): assert heurisch(1/(x + y), x) == log(x + y) assert heurisch(1/(x + sqrt(2)), x) == log(x + sqrt(2)) assert simplify(diff(heurisch(log(x + y + z), y), y)) == log(x + y + z) def test_heurisch_symbolic_coeffs_1130(): y = Symbol('y') assert heurisch_wrapper(1/(x**2 + y), x) == Piecewise( (log(x - sqrt(-y))/(2*sqrt(-y)) - log(x + sqrt(-y))/(2*sqrt(-y)), Ne(y, 0)), (-1/x, True)) y = Symbol('y', positive=True) assert heurisch_wrapper(1/(x**2 + y), x) == (atan(x/sqrt(y))/sqrt(y)) def test_heurisch_hacking(): assert heurisch(sqrt(1 + 7*x**2), x, hints=[]) == \ x*sqrt(1 + 7*x**2)/2 + sqrt(7)*asinh(sqrt(7)*x)/14 assert heurisch(sqrt(1 - 7*x**2), x, hints=[]) == \ x*sqrt(1 - 7*x**2)/2 + sqrt(7)*asin(sqrt(7)*x)/14 assert heurisch(1/sqrt(1 + 7*x**2), x, hints=[]) == \ sqrt(7)*asinh(sqrt(7)*x)/7 assert heurisch(1/sqrt(1 - 7*x**2), x, hints=[]) == \ sqrt(7)*asin(sqrt(7)*x)/7 assert heurisch(exp(-7*x**2), x, hints=[]) == \ sqrt(7*pi)*erf(sqrt(7)*x)/14 assert heurisch(1/sqrt(9 - 4*x**2), x, hints=[]) == \ asin(x*Rational(2, 3))/2 assert heurisch(1/sqrt(9 + 4*x**2), x, hints=[]) == \ asinh(x*Rational(2, 3))/2 def test_heurisch_function(): assert heurisch(f(x), x) is None @XFAIL def test_heurisch_function_derivative(): # TODO: it looks like this used to work just by coincindence and # thanks to sloppy implementation. Investigate why this used to # work at all and if support for this can be restored. df = diff(f(x), x) assert heurisch(f(x)*df, x) == f(x)**2/2 assert heurisch(f(x)**2*df, x) == f(x)**3/3 assert heurisch(df/f(x), x) == log(f(x)) def test_heurisch_wrapper(): f = 1/(y + x) assert heurisch_wrapper(f, x) == log(x + y) f = 1/(y - x) assert heurisch_wrapper(f, x) == -log(x - y) f = 1/((y - x)*(y + x)) assert heurisch_wrapper(f, x) == Piecewise( (-log(x - y)/(2*y) + log(x + y)/(2*y), Ne(y, 0)), (1/x, True)) # issue 6926 f = sqrt(x**2/((y - x)*(y + x))) assert heurisch_wrapper(f, x) == x*sqrt(x**2/(-x**2 + y**2)) \ - y**2*sqrt(x**2/(-x**2 + y**2))/x def test_issue_3609(): assert heurisch(1/(x * (1 + log(x)**2)), x) == atan(log(x)) ### These are examples from the Poor Man's Integrator ### http://www-sop.inria.fr/cafe/Manuel.Bronstein/pmint/examples/ def test_pmint_rat(): # TODO: heurisch() is off by a constant: -3/4. Possibly different permutation # would give the optimal result? def drop_const(expr, x): if expr.is_Add: return Add(*[ arg for arg in expr.args if arg.has(x) ]) else: return expr f = (x**7 - 24*x**4 - 4*x**2 + 8*x - 8)/(x**8 + 6*x**6 + 12*x**4 + 8*x**2) g = (4 + 8*x**2 + 6*x + 3*x**3)/(x**5 + 4*x**3 + 4*x) + log(x) assert drop_const(ratsimp(heurisch(f, x)), x) == g def test_pmint_trig(): f = (x - tan(x)) / tan(x)**2 + tan(x) g = -x**2/2 - x/tan(x) + log(tan(x)**2 + 1)/2 assert heurisch(f, x) == g @slow # 8 seconds on 3.4 GHz def test_pmint_logexp(): if ON_TRAVIS: # See https://github.com/sympy/sympy/pull/12795 skip("Too slow for travis.") f = (1 + x + x*exp(x))*(x + log(x) + exp(x) - 1)/(x + log(x) + exp(x))**2/x g = log(x + exp(x) + log(x)) + 1/(x + exp(x) + log(x)) assert ratsimp(heurisch(f, x)) == g def test_pmint_erf(): f = exp(-x**2)*erf(x)/(erf(x)**3 - erf(x)**2 - erf(x) + 1) g = sqrt(pi)*log(erf(x) - 1)/8 - sqrt(pi)*log(erf(x) + 1)/8 - sqrt(pi)/(4*erf(x) - 4) assert ratsimp(heurisch(f, x)) == g def test_pmint_LambertW(): f = LambertW(x) g = x*LambertW(x) - x + x/LambertW(x) assert heurisch(f, x) == g def test_pmint_besselj(): f = besselj(nu + 1, x)/besselj(nu, x) g = nu*log(x) - log(besselj(nu, x)) assert heurisch(f, x) == g f = (nu*besselj(nu, x) - x*besselj(nu + 1, x))/x g = besselj(nu, x) assert heurisch(f, x) == g f = jn(nu + 1, x)/jn(nu, x) g = nu*log(x) - log(jn(nu, x)) assert heurisch(f, x) == g @slow def test_pmint_bessel_products(): # Note: Derivatives of Bessel functions have many forms. # Recurrence relations are needed for comparisons. if ON_TRAVIS: skip("Too slow for travis.") f = x*besselj(nu, x)*bessely(nu, 2*x) g = -2*x*besselj(nu, x)*bessely(nu - 1, 2*x)/3 + x*besselj(nu - 1, x)*bessely(nu, 2*x)/3 assert heurisch(f, x) == g f = x*besselj(nu, x)*besselk(nu, 2*x) g = -2*x*besselj(nu, x)*besselk(nu - 1, 2*x)/5 - x*besselj(nu - 1, x)*besselk(nu, 2*x)/5 assert heurisch(f, x) == g @slow # 110 seconds on 3.4 GHz def test_pmint_WrightOmega(): if ON_TRAVIS: skip("Too slow for travis.") def omega(x): return LambertW(exp(x)) f = (1 + omega(x) * (2 + cos(omega(x)) * (x + omega(x))))/(1 + omega(x))/(x + omega(x)) g = log(x + LambertW(exp(x))) + sin(LambertW(exp(x))) assert heurisch(f, x) == g def test_RR(): # Make sure the algorithm does the right thing if the ring is RR. See # issue 8685. assert heurisch(sqrt(1 + 0.25*x**2), x, hints=[]) == \ 0.5*x*sqrt(0.25*x**2 + 1) + 1.0*asinh(0.5*x) # TODO: convert the rest of PMINT tests: # Airy functions # f = (x - AiryAi(x)*AiryAi(1, x)) / (x**2 - AiryAi(x)**2) # g = Rational(1,2)*ln(x + AiryAi(x)) + Rational(1,2)*ln(x - AiryAi(x)) # f = x**2 * AiryAi(x) # g = -AiryAi(x) + AiryAi(1, x)*x # Whittaker functions # f = WhittakerW(mu + 1, nu, x) / (WhittakerW(mu, nu, x) * x) # g = x/2 - mu*ln(x) - ln(WhittakerW(mu, nu, x))
f4762d3811798439ebdc4cabdaa8042e18af25e6ce53304cd1a05672d928e7b4
from sympy import ( Abs, acos, acosh, Add, And, asin, asinh, atan, Ci, cos, sinh, cosh, tanh, Derivative, diff, DiracDelta, E, Ei, Eq, exp, erf, erfc, erfi, EulerGamma, Expr, factor, Function, gamma, gammasimp, I, Idx, im, IndexedBase, integrate, Interval, Lambda, LambertW, log, Matrix, Max, meijerg, Min, nan, Ne, O, oo, pi, Piecewise, polar_lift, Poly, polygamma, Rational, re, S, Si, sign, simplify, sin, sinc, SingularityFunction, sqrt, sstr, Sum, Symbol, summation, symbols, sympify, tan, trigsimp, Tuple, lerchphi, exp_polar, li, hyper ) from sympy.core.expr import unchanged from sympy.functions.elementary.complexes import periodic_argument from sympy.functions.elementary.integers import floor from sympy.integrals.integrals import Integral from sympy.integrals.risch import NonElementaryIntegral from sympy.physics import units from sympy.testing.pytest import (raises, slow, skip, ON_TRAVIS, warns_deprecated_sympy) from sympy.testing.randtest import verify_numerically x, y, a, t, x_1, x_2, z, s, b = symbols('x y a t x_1 x_2 z s b') n = Symbol('n', integer=True) f = Function('f') def NS(e, n=15, **options): return sstr(sympify(e).evalf(n, **options), full_prec=True) def test_poly_deprecated(): p = Poly(2*x, x) assert p.integrate(x) == Poly(x**2, x, domain='QQ') with warns_deprecated_sympy(): integrate(p, x) with warns_deprecated_sympy(): Integral(p, (x,)) def test_principal_value(): g = 1 / x assert Integral(g, (x, -oo, oo)).principal_value() == 0 assert Integral(g, (y, -oo, oo)).principal_value() == oo * sign(1 / x) raises(ValueError, lambda: Integral(g, (x)).principal_value()) raises(ValueError, lambda: Integral(g).principal_value()) l = 1 / ((x ** 3) - 1) assert Integral(l, (x, -oo, oo)).principal_value() == -sqrt(3)*pi/3 raises(ValueError, lambda: Integral(l, (x, -oo, 1)).principal_value()) d = 1 / (x ** 2 - 1) assert Integral(d, (x, -oo, oo)).principal_value() == 0 assert Integral(d, (x, -2, 2)).principal_value() == -log(3) v = x / (x ** 2 - 1) assert Integral(v, (x, -oo, oo)).principal_value() == 0 assert Integral(v, (x, -2, 2)).principal_value() == 0 s = x ** 2 / (x ** 2 - 1) assert Integral(s, (x, -oo, oo)).principal_value() is oo assert Integral(s, (x, -2, 2)).principal_value() == -log(3) + 4 f = 1 / ((x ** 2 - 1) * (1 + x ** 2)) assert Integral(f, (x, -oo, oo)).principal_value() == -pi / 2 assert Integral(f, (x, -2, 2)).principal_value() == -atan(2) - log(3) / 2 def diff_test(i): """Return the set of symbols, s, which were used in testing that i.diff(s) agrees with i.doit().diff(s). If there is an error then the assertion will fail, causing the test to fail.""" syms = i.free_symbols for s in syms: assert (i.diff(s).doit() - i.doit().diff(s)).expand() == 0 return syms def test_improper_integral(): assert integrate(log(x), (x, 0, 1)) == -1 assert integrate(x**(-2), (x, 1, oo)) == 1 assert integrate(1/(1 + exp(x)), (x, 0, oo)) == log(2) def test_constructor(): # this is shared by Sum, so testing Integral's constructor # is equivalent to testing Sum's s1 = Integral(n, n) assert s1.limits == (Tuple(n),) s2 = Integral(n, (n,)) assert s2.limits == (Tuple(n),) s3 = Integral(Sum(x, (x, 1, y))) assert s3.limits == (Tuple(y),) s4 = Integral(n, Tuple(n,)) assert s4.limits == (Tuple(n),) s5 = Integral(n, (n, Interval(1, 2))) assert s5.limits == (Tuple(n, 1, 2),) # Testing constructor with inequalities: s6 = Integral(n, n > 10) assert s6.limits == (Tuple(n, 10, oo),) s7 = Integral(n, (n > 2) & (n < 5)) assert s7.limits == (Tuple(n, 2, 5),) def test_basics(): assert Integral(0, x) != 0 assert Integral(x, (x, 1, 1)) != 0 assert Integral(oo, x) != oo assert Integral(S.NaN, x) is S.NaN assert diff(Integral(y, y), x) == 0 assert diff(Integral(x, (x, 0, 1)), x) == 0 assert diff(Integral(x, x), x) == x assert diff(Integral(t, (t, 0, x)), x) == x e = (t + 1)**2 assert diff(integrate(e, (t, 0, x)), x) == \ diff(Integral(e, (t, 0, x)), x).doit().expand() == \ ((1 + x)**2).expand() assert diff(integrate(e, (t, 0, x)), t) == \ diff(Integral(e, (t, 0, x)), t) == 0 assert diff(integrate(e, (t, 0, x)), a) == \ diff(Integral(e, (t, 0, x)), a) == 0 assert diff(integrate(e, t), a) == diff(Integral(e, t), a) == 0 assert integrate(e, (t, a, x)).diff(x) == \ Integral(e, (t, a, x)).diff(x).doit().expand() assert Integral(e, (t, a, x)).diff(x).doit() == ((1 + x)**2) assert integrate(e, (t, x, a)).diff(x).doit() == (-(1 + x)**2).expand() assert integrate(t**2, (t, x, 2*x)).diff(x) == 7*x**2 assert Integral(x, x).atoms() == {x} assert Integral(f(x), (x, 0, 1)).atoms() == {S.Zero, S.One, x} assert diff_test(Integral(x, (x, 3*y))) == {y} assert diff_test(Integral(x, (a, 3*y))) == {x, y} assert integrate(x, (x, oo, oo)) == 0 #issue 8171 assert integrate(x, (x, -oo, -oo)) == 0 # sum integral of terms assert integrate(y + x + exp(x), x) == x*y + x**2/2 + exp(x) assert Integral(x).is_commutative n = Symbol('n', commutative=False) assert Integral(n + x, x).is_commutative is False def test_diff_wrt(): class Test(Expr): _diff_wrt = True is_commutative = True t = Test() assert integrate(t + 1, t) == t**2/2 + t assert integrate(t + 1, (t, 0, 1)) == Rational(3, 2) raises(ValueError, lambda: integrate(x + 1, x + 1)) raises(ValueError, lambda: integrate(x + 1, (x + 1, 0, 1))) def test_basics_multiple(): assert diff_test(Integral(x, (x, 3*x, 5*y), (y, x, 2*x))) == {x} assert diff_test(Integral(x, (x, 5*y), (y, x, 2*x))) == {x} assert diff_test(Integral(x, (x, 5*y), (y, y, 2*x))) == {x, y} assert diff_test(Integral(y, y, x)) == {x, y} assert diff_test(Integral(y*x, x, y)) == {x, y} assert diff_test(Integral(x + y, y, (y, 1, x))) == {x} assert diff_test(Integral(x + y, (x, x, y), (y, y, x))) == {x, y} def test_conjugate_transpose(): A, B = symbols("A B", commutative=False) x = Symbol("x", complex=True) p = Integral(A*B, (x,)) assert p.adjoint().doit() == p.doit().adjoint() assert p.conjugate().doit() == p.doit().conjugate() assert p.transpose().doit() == p.doit().transpose() x = Symbol("x", real=True) p = Integral(A*B, (x,)) assert p.adjoint().doit() == p.doit().adjoint() assert p.conjugate().doit() == p.doit().conjugate() assert p.transpose().doit() == p.doit().transpose() def test_integration(): assert integrate(0, (t, 0, x)) == 0 assert integrate(3, (t, 0, x)) == 3*x assert integrate(t, (t, 0, x)) == x**2/2 assert integrate(3*t, (t, 0, x)) == 3*x**2/2 assert integrate(3*t**2, (t, 0, x)) == x**3 assert integrate(1/t, (t, 1, x)) == log(x) assert integrate(-1/t**2, (t, 1, x)) == 1/x - 1 assert integrate(t**2 + 5*t - 8, (t, 0, x)) == x**3/3 + 5*x**2/2 - 8*x assert integrate(x**2, x) == x**3/3 assert integrate((3*t*x)**5, x) == (3*t)**5 * x**6 / 6 b = Symbol("b") c = Symbol("c") assert integrate(a*t, (t, 0, x)) == a*x**2/2 assert integrate(a*t**4, (t, 0, x)) == a*x**5/5 assert integrate(a*t**2 + b*t + c, (t, 0, x)) == a*x**3/3 + b*x**2/2 + c*x def test_multiple_integration(): assert integrate((x**2)*(y**2), (x, 0, 1), (y, -1, 2)) == Rational(1) assert integrate((y**2)*(x**2), x, y) == Rational(1, 9)*(x**3)*(y**3) assert integrate(1/(x + 3)/(1 + x)**3, x) == \ log(3 + x)*Rational(-1, 8) + log(1 + x)*Rational(1, 8) + x/(4 + 8*x + 4*x**2) assert integrate(sin(x*y)*y, (x, 0, 1), (y, 0, 1)) == -sin(1) + 1 def test_issue_3532(): assert integrate(exp(-x), (x, 0, oo)) == 1 def test_issue_3560(): assert integrate(sqrt(x)**3, x) == 2*sqrt(x)**5/5 assert integrate(sqrt(x), x) == 2*sqrt(x)**3/3 assert integrate(1/sqrt(x)**3, x) == -2/sqrt(x) def test_issue_18038(): raises(AttributeError, lambda: integrate((x, x))) def test_integrate_poly(): p = Poly(x + x**2*y + y**3, x, y) with warns_deprecated_sympy(): qx = integrate(p, x) with warns_deprecated_sympy(): qy = integrate(p, y) assert isinstance(qx, Poly) is True assert isinstance(qy, Poly) is True assert qx.gens == (x, y) assert qy.gens == (x, y) assert qx.as_expr() == x**2/2 + x**3*y/3 + x*y**3 assert qy.as_expr() == x*y + x**2*y**2/2 + y**4/4 def test_integrate_poly_defined(): p = Poly(x + x**2*y + y**3, x, y) with warns_deprecated_sympy(): Qx = integrate(p, (x, 0, 1)) with warns_deprecated_sympy(): Qy = integrate(p, (y, 0, pi)) assert isinstance(Qx, Poly) is True assert isinstance(Qy, Poly) is True assert Qx.gens == (y,) assert Qy.gens == (x,) assert Qx.as_expr() == S.Half + y/3 + y**3 assert Qy.as_expr() == pi**4/4 + pi*x + pi**2*x**2/2 def test_integrate_omit_var(): y = Symbol('y') assert integrate(x) == x**2/2 raises(ValueError, lambda: integrate(2)) raises(ValueError, lambda: integrate(x*y)) def test_integrate_poly_accurately(): y = Symbol('y') assert integrate(x*sin(y), x) == x**2*sin(y)/2 # when passed to risch_norman, this will be a CPU hog, so this really # checks, that integrated function is recognized as polynomial assert integrate(x**1000*sin(y), x) == x**1001*sin(y)/1001 def test_issue_3635(): y = Symbol('y') assert integrate(x**2, y) == x**2*y assert integrate(x**2, (y, -1, 1)) == 2*x**2 # works in sympy and py.test but hangs in `setup.py test` def test_integrate_linearterm_pow(): # check integrate((a*x+b)^c, x) -- issue 3499 y = Symbol('y', positive=True) # TODO: Remove conds='none' below, let the assumption take care of it. assert integrate(x**y, x, conds='none') == x**(y + 1)/(y + 1) assert integrate((exp(y)*x + 1/y)**(1 + sin(y)), x, conds='none') == \ exp(-y)*(exp(y)*x + 1/y)**(2 + sin(y)) / (2 + sin(y)) def test_issue_3618(): assert integrate(pi*sqrt(x), x) == 2*pi*sqrt(x)**3/3 assert integrate(pi*sqrt(x) + E*sqrt(x)**3, x) == \ 2*pi*sqrt(x)**3/3 + 2*E *sqrt(x)**5/5 def test_issue_3623(): assert integrate(cos((n + 1)*x), x) == Piecewise( (sin(x*(n + 1))/(n + 1), Ne(n + 1, 0)), (x, True)) assert integrate(cos((n - 1)*x), x) == Piecewise( (sin(x*(n - 1))/(n - 1), Ne(n - 1, 0)), (x, True)) assert integrate(cos((n + 1)*x) + cos((n - 1)*x), x) == \ Piecewise((sin(x*(n - 1))/(n - 1), Ne(n - 1, 0)), (x, True)) + \ Piecewise((sin(x*(n + 1))/(n + 1), Ne(n + 1, 0)), (x, True)) def test_issue_3664(): n = Symbol('n', integer=True, nonzero=True) assert integrate(-1./2 * x * sin(n * pi * x/2), [x, -2, 0]) == \ 2.0*cos(pi*n)/(pi*n) assert integrate(x * sin(n * pi * x/2) * Rational(-1, 2), [x, -2, 0]) == \ 2*cos(pi*n)/(pi*n) def test_issue_3679(): # definite integration of rational functions gives wrong answers assert NS(Integral(1/(x**2 - 8*x + 17), (x, 2, 4))) == '1.10714871779409' def test_issue_3686(): # remove this when fresnel itegrals are implemented from sympy import expand_func, fresnels assert expand_func(integrate(sin(x**2), x)) == \ sqrt(2)*sqrt(pi)*fresnels(sqrt(2)*x/sqrt(pi))/2 def test_integrate_units(): m = units.m s = units.s assert integrate(x * m/s, (x, 1*s, 5*s)) == 12*m*s def test_transcendental_functions(): assert integrate(LambertW(2*x), x) == \ -x + x*LambertW(2*x) + x/LambertW(2*x) def test_log_polylog(): assert integrate(log(1 - x)/x, (x, 0, 1)) == -pi**2/6 assert integrate(log(x)*(1 - x)**(-1), (x, 0, 1)) == -pi**2/6 def test_issue_3740(): f = 4*log(x) - 2*log(x)**2 fid = diff(integrate(f, x), x) assert abs(f.subs(x, 42).evalf() - fid.subs(x, 42).evalf()) < 1e-10 def test_issue_3788(): assert integrate(1/(1 + x**2), x) == atan(x) def test_issue_3952(): f = sin(x) assert integrate(f, x) == -cos(x) raises(ValueError, lambda: integrate(f, 2*x)) def test_issue_4516(): assert integrate(2**x - 2*x, x) == 2**x/log(2) - x**2 def test_issue_7450(): ans = integrate(exp(-(1 + I)*x), (x, 0, oo)) assert re(ans) == S.Half and im(ans) == Rational(-1, 2) def test_issue_8623(): assert integrate((1 + cos(2*x)) / (3 - 2*cos(2*x)), (x, 0, pi)) == -pi/2 + sqrt(5)*pi/2 assert integrate((1 + cos(2*x))/(3 - 2*cos(2*x))) == -x/2 + sqrt(5)*(atan(sqrt(5)*tan(x)) + \ pi*floor((x - pi/2)/pi))/2 def test_issue_9569(): assert integrate(1 / (2 - cos(x)), (x, 0, pi)) == pi/sqrt(3) assert integrate(1/(2 - cos(x))) == 2*sqrt(3)*(atan(sqrt(3)*tan(x/2)) + pi*floor((x/2 - pi/2)/pi))/3 def test_issue_13733(): s = Symbol('s', positive=True) pz = exp(-(z - y)**2/(2*s*s))/sqrt(2*pi*s*s) pzgx = integrate(pz, (z, x, oo)) assert integrate(pzgx, (x, 0, oo)) == sqrt(2)*s*exp(-y**2/(2*s**2))/(2*sqrt(pi)) + \ y*erf(sqrt(2)*y/(2*s))/2 + y/2 def test_issue_13749(): assert integrate(1 / (2 + cos(x)), (x, 0, pi)) == pi/sqrt(3) assert integrate(1/(2 + cos(x))) == 2*sqrt(3)*(atan(sqrt(3)*tan(x/2)/3) + pi*floor((x/2 - pi/2)/pi))/3 def test_issue_18133(): assert integrate(exp(x)/(1 + x)**2, x) == NonElementaryIntegral(exp(x)/(x + 1)**2, x) def test_matrices(): M = Matrix(2, 2, lambda i, j: (i + j + 1)*sin((i + j + 1)*x)) assert integrate(M, x) == Matrix([ [-cos(x), -cos(2*x)], [-cos(2*x), -cos(3*x)], ]) def test_integrate_functions(): # issue 4111 assert integrate(f(x), x) == Integral(f(x), x) assert integrate(f(x), (x, 0, 1)) == Integral(f(x), (x, 0, 1)) assert integrate(f(x)*diff(f(x), x), x) == f(x)**2/2 assert integrate(diff(f(x), x) / f(x), x) == log(f(x)) def test_integrate_derivatives(): assert integrate(Derivative(f(x), x), x) == f(x) assert integrate(Derivative(f(y), y), x) == x*Derivative(f(y), y) assert integrate(Derivative(f(x), x)**2, x) == \ Integral(Derivative(f(x), x)**2, x) def test_transform(): a = Integral(x**2 + 1, (x, -1, 2)) fx = x fy = 3*y + 1 assert a.doit() == a.transform(fx, fy).doit() assert a.transform(fx, fy).transform(fy, fx) == a fx = 3*x + 1 fy = y assert a.transform(fx, fy).transform(fy, fx) == a a = Integral(sin(1/x), (x, 0, 1)) assert a.transform(x, 1/y) == Integral(sin(y)/y**2, (y, 1, oo)) assert a.transform(x, 1/y).transform(y, 1/x) == a a = Integral(exp(-x**2), (x, -oo, oo)) assert a.transform(x, 2*y) == Integral(2*exp(-4*y**2), (y, -oo, oo)) # < 3 arg limit handled properly assert Integral(x, x).transform(x, a*y).doit() == \ Integral(y*a**2, y).doit() _3 = S(3) assert Integral(x, (x, 0, -_3)).transform(x, 1/y).doit() == \ Integral(-1/x**3, (x, -oo, -1/_3)).doit() assert Integral(x, (x, 0, _3)).transform(x, 1/y) == \ Integral(y**(-3), (y, 1/_3, oo)) # issue 8400 i = Integral(x + y, (x, 1, 2), (y, 1, 2)) assert i.transform(x, (x + 2*y, x)).doit() == \ i.transform(x, (x + 2*z, x)).doit() == 3 i = Integral(x, (x, a, b)) assert i.transform(x, 2*s) == Integral(4*s, (s, a/2, b/2)) raises(ValueError, lambda: i.transform(x, 1)) raises(ValueError, lambda: i.transform(x, s*t)) raises(ValueError, lambda: i.transform(x, -s)) raises(ValueError, lambda: i.transform(x, (s, t))) raises(ValueError, lambda: i.transform(2*x, 2*s)) i = Integral(x**2, (x, 1, 2)) raises(ValueError, lambda: i.transform(x**2, s)) am = Symbol('a', negative=True) bp = Symbol('b', positive=True) i = Integral(x, (x, bp, am)) i.transform(x, 2*s) assert i.transform(x, 2*s) == Integral(-4*s, (s, am/2, bp/2)) i = Integral(x, (x, a)) assert i.transform(x, 2*s) == Integral(4*s, (s, a/2)) def test_issue_4052(): f = S.Half*asin(x) + x*sqrt(1 - x**2)/2 assert integrate(cos(asin(x)), x) == f assert integrate(sin(acos(x)), x) == f @slow def test_evalf_integrals(): assert NS(Integral(x, (x, 2, 5)), 15) == '10.5000000000000' gauss = Integral(exp(-x**2), (x, -oo, oo)) assert NS(gauss, 15) == '1.77245385090552' assert NS(gauss**2 - pi + E*Rational( 1, 10**20), 15) in ('2.71828182845904e-20', '2.71828182845905e-20') # A monster of an integral from http://mathworld.wolfram.com/DefiniteIntegral.html t = Symbol('t') a = 8*sqrt(3)/(1 + 3*t**2) b = 16*sqrt(2)*(3*t + 1)*sqrt(4*t**2 + t + 1)**3 c = (3*t**2 + 1)*(11*t**2 + 2*t + 3)**2 d = sqrt(2)*(249*t**2 + 54*t + 65)/(11*t**2 + 2*t + 3)**2 f = a - b/c - d assert NS(Integral(f, (t, 0, 1)), 50) == \ NS((3*sqrt(2) - 49*pi + 162*atan(sqrt(2)))/12, 50) # http://mathworld.wolfram.com/VardisIntegral.html assert NS(Integral(log(log(1/x))/(1 + x + x**2), (x, 0, 1)), 15) == \ NS('pi/sqrt(3) * log(2*pi**(5/6) / gamma(1/6))', 15) # http://mathworld.wolfram.com/AhmedsIntegral.html assert NS(Integral(atan(sqrt(x**2 + 2))/(sqrt(x**2 + 2)*(x**2 + 1)), (x, 0, 1)), 15) == NS(5*pi**2/96, 15) # http://mathworld.wolfram.com/AbelsIntegral.html assert NS(Integral(x/((exp(pi*x) - exp( -pi*x))*(x**2 + 1)), (x, 0, oo)), 15) == NS('log(2)/2-1/4', 15) # Complex part trimming # http://mathworld.wolfram.com/VardisIntegral.html assert NS(Integral(log(log(sin(x)/cos(x))), (x, pi/4, pi/2)), 15, chop=True) == \ NS('pi/4*log(4*pi**3/gamma(1/4)**4)', 15) # # Endpoints causing trouble (rounding error in integration points -> complex log) assert NS( 2 + Integral(log(2*cos(x/2)), (x, -pi, pi)), 17, chop=True) == NS(2, 17) assert NS( 2 + Integral(log(2*cos(x/2)), (x, -pi, pi)), 20, chop=True) == NS(2, 20) assert NS( 2 + Integral(log(2*cos(x/2)), (x, -pi, pi)), 22, chop=True) == NS(2, 22) # Needs zero handling assert NS(pi - 4*Integral( 'sqrt(1-x**2)', (x, 0, 1)), 15, maxn=30, chop=True) in ('0.0', '0') # Oscillatory quadrature a = Integral(sin(x)/x**2, (x, 1, oo)).evalf(maxn=15) assert 0.49 < a < 0.51 assert NS( Integral(sin(x)/x**2, (x, 1, oo)), quad='osc') == '0.504067061906928' assert NS(Integral( cos(pi*x + 1)/x, (x, -oo, -1)), quad='osc') == '0.276374705640365' # indefinite integrals aren't evaluated assert NS(Integral(x, x)) == 'Integral(x, x)' assert NS(Integral(x, (x, y))) == 'Integral(x, (x, y))' def test_evalf_issue_939(): # https://github.com/sympy/sympy/issues/4038 # The output form of an integral may differ by a step function between # revisions, making this test a bit useless. This can't be said about # other two tests. For now, all values of this evaluation are used here, # but in future this should be reconsidered. assert NS(integrate(1/(x**5 + 1), x).subs(x, 4), chop=True) in \ ['-0.000976138910649103', '0.965906660135753', '1.93278945918216'] assert NS(Integral(1/(x**5 + 1), (x, 2, 4))) == '0.0144361088886740' assert NS( integrate(1/(x**5 + 1), (x, 2, 4)), chop=True) == '0.0144361088886740' def test_double_previously_failing_integrals(): # Double integrals not implemented <- Sure it is! res = integrate(sqrt(x) + x*y, (x, 1, 2), (y, -1, 1)) # Old numerical test assert NS(res, 15) == '2.43790283299492' # Symbolic test assert res == Rational(-4, 3) + 8*sqrt(2)/3 # double integral + zero detection assert integrate(sin(x + x*y), (x, -1, 1), (y, -1, 1)) is S.Zero def test_integrate_SingularityFunction(): in_1 = SingularityFunction(x, a, 3) + SingularityFunction(x, 5, -1) out_1 = SingularityFunction(x, a, 4)/4 + SingularityFunction(x, 5, 0) assert integrate(in_1, x) == out_1 in_2 = 10*SingularityFunction(x, 4, 0) - 5*SingularityFunction(x, -6, -2) out_2 = 10*SingularityFunction(x, 4, 1) - 5*SingularityFunction(x, -6, -1) assert integrate(in_2, x) == out_2 in_3 = 2*x**2*y -10*SingularityFunction(x, -4, 7) - 2*SingularityFunction(y, 10, -2) out_3_1 = 2*x**3*y/3 - 2*x*SingularityFunction(y, 10, -2) - 5*SingularityFunction(x, -4, 8)/4 out_3_2 = x**2*y**2 - 10*y*SingularityFunction(x, -4, 7) - 2*SingularityFunction(y, 10, -1) assert integrate(in_3, x) == out_3_1 assert integrate(in_3, y) == out_3_2 assert unchanged(Integral, in_3, (x,)) assert Integral(in_3, x) == Integral(in_3, (x,)) assert Integral(in_3, x).doit() == out_3_1 in_4 = 10*SingularityFunction(x, -4, 7) - 2*SingularityFunction(x, 10, -2) out_4 = 5*SingularityFunction(x, -4, 8)/4 - 2*SingularityFunction(x, 10, -1) assert integrate(in_4, (x, -oo, x)) == out_4 assert integrate(SingularityFunction(x, 5, -1), x) == SingularityFunction(x, 5, 0) assert integrate(SingularityFunction(x, 0, -1), (x, -oo, oo)) == 1 assert integrate(5*SingularityFunction(x, 5, -1), (x, -oo, oo)) == 5 assert integrate(SingularityFunction(x, 5, -1) * f(x), (x, -oo, oo)) == f(5) def test_integrate_DiracDelta(): # This is here to check that deltaintegrate is being called, but also # to test definite integrals. More tests are in test_deltafunctions.py assert integrate(DiracDelta(x) * f(x), (x, -oo, oo)) == f(0) assert integrate(DiracDelta(x)**2, (x, -oo, oo)) == DiracDelta(0) # issue 4522 assert integrate(integrate((4 - 4*x + x*y - 4*y) * \ DiracDelta(x)*DiracDelta(y - 1), (x, 0, 1)), (y, 0, 1)) == 0 # issue 5729 p = exp(-(x**2 + y**2))/pi assert integrate(p*DiracDelta(x - 10*y), (x, -oo, oo), (y, -oo, oo)) == \ integrate(p*DiracDelta(x - 10*y), (y, -oo, oo), (x, -oo, oo)) == \ integrate(p*DiracDelta(10*x - y), (x, -oo, oo), (y, -oo, oo)) == \ integrate(p*DiracDelta(10*x - y), (y, -oo, oo), (x, -oo, oo)) == \ 1/sqrt(101*pi) def test_integrate_returns_piecewise(): assert integrate(x**y, x) == Piecewise( (x**(y + 1)/(y + 1), Ne(y, -1)), (log(x), True)) assert integrate(x**y, y) == Piecewise( (x**y/log(x), Ne(log(x), 0)), (y, True)) assert integrate(exp(n*x), x) == Piecewise( (exp(n*x)/n, Ne(n, 0)), (x, True)) assert integrate(x*exp(n*x), x) == Piecewise( ((n*x - 1)*exp(n*x)/n**2, Ne(n**2, 0)), (x**2/2, True)) assert integrate(x**(n*y), x) == Piecewise( (x**(n*y + 1)/(n*y + 1), Ne(n*y, -1)), (log(x), True)) assert integrate(x**(n*y), y) == Piecewise( (x**(n*y)/(n*log(x)), Ne(n*log(x), 0)), (y, True)) assert integrate(cos(n*x), x) == Piecewise( (sin(n*x)/n, Ne(n, 0)), (x, True)) assert integrate(cos(n*x)**2, x) == Piecewise( ((n*x/2 + sin(n*x)*cos(n*x)/2)/n, Ne(n, 0)), (x, True)) assert integrate(x*cos(n*x), x) == Piecewise( (x*sin(n*x)/n + cos(n*x)/n**2, Ne(n, 0)), (x**2/2, True)) assert integrate(sin(n*x), x) == Piecewise( (-cos(n*x)/n, Ne(n, 0)), (0, True)) assert integrate(sin(n*x)**2, x) == Piecewise( ((n*x/2 - sin(n*x)*cos(n*x)/2)/n, Ne(n, 0)), (0, True)) assert integrate(x*sin(n*x), x) == Piecewise( (-x*cos(n*x)/n + sin(n*x)/n**2, Ne(n, 0)), (0, True)) assert integrate(exp(x*y), (x, 0, z)) == Piecewise( (exp(y*z)/y - 1/y, (y > -oo) & (y < oo) & Ne(y, 0)), (z, True)) def test_integrate_max_min(): x = symbols('x', real=True) assert integrate(Min(x, 2), (x, 0, 3)) == 4 assert integrate(Max(x**2, x**3), (x, 0, 2)) == Rational(49, 12) assert integrate(Min(exp(x), exp(-x))**2, x) == Piecewise( \ (exp(2*x)/2, x <= 0), (1 - exp(-2*x)/2, True)) # issue 7907 c = symbols('c', extended_real=True) int1 = integrate(Max(c, x)*exp(-x**2), (x, -oo, oo)) int2 = integrate(c*exp(-x**2), (x, -oo, c)) int3 = integrate(x*exp(-x**2), (x, c, oo)) assert int1 == int2 + int3 == sqrt(pi)*c*erf(c)/2 + \ sqrt(pi)*c/2 + exp(-c**2)/2 def test_integrate_Abs_sign(): assert integrate(Abs(x), (x, -2, 1)) == Rational(5, 2) assert integrate(Abs(x), (x, 0, 1)) == S.Half assert integrate(Abs(x + 1), (x, 0, 1)) == Rational(3, 2) assert integrate(Abs(x**2 - 1), (x, -2, 2)) == 4 assert integrate(Abs(x**2 - 3*x), (x, -15, 15)) == 2259 assert integrate(sign(x), (x, -1, 2)) == 1 assert integrate(sign(x)*sin(x), (x, -pi, pi)) == 4 assert integrate(sign(x - 2) * x**2, (x, 0, 3)) == Rational(11, 3) t, s = symbols('t s', real=True) assert integrate(Abs(t), t) == Piecewise( (-t**2/2, t <= 0), (t**2/2, True)) assert integrate(Abs(2*t - 6), t) == Piecewise( (-t**2 + 6*t, t <= 3), (t**2 - 6*t + 18, True)) assert (integrate(abs(t - s**2), (t, 0, 2)) == 2*s**2*Min(2, s**2) - 2*s**2 - Min(2, s**2)**2 + 2) assert integrate(exp(-Abs(t)), t) == Piecewise( (exp(t), t <= 0), (2 - exp(-t), True)) assert integrate(sign(2*t - 6), t) == Piecewise( (-t, t < 3), (t - 6, True)) assert integrate(2*t*sign(t**2 - 1), t) == Piecewise( (t**2, t < -1), (-t**2 + 2, t < 1), (t**2, True)) assert integrate(sign(t), (t, s + 1)) == Piecewise( (s + 1, s + 1 > 0), (-s - 1, s + 1 < 0), (0, True)) def test_subs1(): e = Integral(exp(x - y), x) assert e.subs(y, 3) == Integral(exp(x - 3), x) e = Integral(exp(x - y), (x, 0, 1)) assert e.subs(y, 3) == Integral(exp(x - 3), (x, 0, 1)) f = Lambda(x, exp(-x**2)) conv = Integral(f(x - y)*f(y), (y, -oo, oo)) assert conv.subs({x: 0}) == Integral(exp(-2*y**2), (y, -oo, oo)) def test_subs2(): e = Integral(exp(x - y), x, t) assert e.subs(y, 3) == Integral(exp(x - 3), x, t) e = Integral(exp(x - y), (x, 0, 1), (t, 0, 1)) assert e.subs(y, 3) == Integral(exp(x - 3), (x, 0, 1), (t, 0, 1)) f = Lambda(x, exp(-x**2)) conv = Integral(f(x - y)*f(y), (y, -oo, oo), (t, 0, 1)) assert conv.subs({x: 0}) == Integral(exp(-2*y**2), (y, -oo, oo), (t, 0, 1)) def test_subs3(): e = Integral(exp(x - y), (x, 0, y), (t, y, 1)) assert e.subs(y, 3) == Integral(exp(x - 3), (x, 0, 3), (t, 3, 1)) f = Lambda(x, exp(-x**2)) conv = Integral(f(x - y)*f(y), (y, -oo, oo), (t, x, 1)) assert conv.subs({x: 0}) == Integral(exp(-2*y**2), (y, -oo, oo), (t, 0, 1)) def test_subs4(): e = Integral(exp(x), (x, 0, y), (t, y, 1)) assert e.subs(y, 3) == Integral(exp(x), (x, 0, 3), (t, 3, 1)) f = Lambda(x, exp(-x**2)) conv = Integral(f(y)*f(y), (y, -oo, oo), (t, x, 1)) assert conv.subs({x: 0}) == Integral(exp(-2*y**2), (y, -oo, oo), (t, 0, 1)) def test_subs5(): e = Integral(exp(-x**2), (x, -oo, oo)) assert e.subs(x, 5) == e e = Integral(exp(-x**2 + y), x) assert e.subs(y, 5) == Integral(exp(-x**2 + 5), x) e = Integral(exp(-x**2 + y), (x, x)) assert e.subs(x, 5) == Integral(exp(y - x**2), (x, 5)) assert e.subs(y, 5) == Integral(exp(-x**2 + 5), x) e = Integral(exp(-x**2 + y), (y, -oo, oo), (x, -oo, oo)) assert e.subs(x, 5) == e assert e.subs(y, 5) == e # Test evaluation of antiderivatives e = Integral(exp(-x**2), (x, x)) assert e.subs(x, 5) == Integral(exp(-x**2), (x, 5)) e = Integral(exp(x), x) assert (e.subs(x,1) - e.subs(x,0) - Integral(exp(x), (x, 0, 1)) ).doit().is_zero def test_subs6(): a, b = symbols('a b') e = Integral(x*y, (x, f(x), f(y))) assert e.subs(x, 1) == Integral(x*y, (x, f(1), f(y))) assert e.subs(y, 1) == Integral(x, (x, f(x), f(1))) e = Integral(x*y, (x, f(x), f(y)), (y, f(x), f(y))) assert e.subs(x, 1) == Integral(x*y, (x, f(1), f(y)), (y, f(1), f(y))) assert e.subs(y, 1) == Integral(x*y, (x, f(x), f(y)), (y, f(x), f(1))) e = Integral(x*y, (x, f(x), f(a)), (y, f(x), f(a))) assert e.subs(a, 1) == Integral(x*y, (x, f(x), f(1)), (y, f(x), f(1))) def test_subs7(): e = Integral(x, (x, 1, y), (y, 1, 2)) assert e.subs({x: 1, y: 2}) == e e = Integral(sin(x) + sin(y), (x, sin(x), sin(y)), (y, 1, 2)) assert e.subs(sin(y), 1) == e assert e.subs(sin(x), 1) == Integral(sin(x) + sin(y), (x, 1, sin(y)), (y, 1, 2)) def test_expand(): e = Integral(f(x)+f(x**2), (x, 1, y)) assert e.expand() == Integral(f(x), (x, 1, y)) + Integral(f(x**2), (x, 1, y)) def test_integration_variable(): raises(ValueError, lambda: Integral(exp(-x**2), 3)) raises(ValueError, lambda: Integral(exp(-x**2), (3, -oo, oo))) def test_expand_integral(): assert Integral(cos(x**2)*(sin(x**2) + 1), (x, 0, 1)).expand() == \ Integral(cos(x**2)*sin(x**2), (x, 0, 1)) + \ Integral(cos(x**2), (x, 0, 1)) assert Integral(cos(x**2)*(sin(x**2) + 1), x).expand() == \ Integral(cos(x**2)*sin(x**2), x) + \ Integral(cos(x**2), x) def test_as_sum_midpoint1(): e = Integral(sqrt(x**3 + 1), (x, 2, 10)) assert e.as_sum(1, method="midpoint") == 8*sqrt(217) assert e.as_sum(2, method="midpoint") == 4*sqrt(65) + 12*sqrt(57) assert e.as_sum(3, method="midpoint") == 8*sqrt(217)/3 + \ 8*sqrt(3081)/27 + 8*sqrt(52809)/27 assert e.as_sum(4, method="midpoint") == 2*sqrt(730) + \ 4*sqrt(7) + 4*sqrt(86) + 6*sqrt(14) assert abs(e.as_sum(4, method="midpoint").n() - e.n()) < 0.5 e = Integral(sqrt(x**3 + y**3), (x, 2, 10), (y, 0, 10)) raises(NotImplementedError, lambda: e.as_sum(4)) def test_as_sum_midpoint2(): e = Integral((x + y)**2, (x, 0, 1)) n = Symbol('n', positive=True, integer=True) assert e.as_sum(1, method="midpoint").expand() == Rational(1, 4) + y + y**2 assert e.as_sum(2, method="midpoint").expand() == Rational(5, 16) + y + y**2 assert e.as_sum(3, method="midpoint").expand() == Rational(35, 108) + y + y**2 assert e.as_sum(4, method="midpoint").expand() == Rational(21, 64) + y + y**2 assert e.as_sum(n, method="midpoint").expand() == \ y**2 + y + Rational(1, 3) - 1/(12*n**2) def test_as_sum_left(): e = Integral((x + y)**2, (x, 0, 1)) assert e.as_sum(1, method="left").expand() == y**2 assert e.as_sum(2, method="left").expand() == Rational(1, 8) + y/2 + y**2 assert e.as_sum(3, method="left").expand() == Rational(5, 27) + y*Rational(2, 3) + y**2 assert e.as_sum(4, method="left").expand() == Rational(7, 32) + y*Rational(3, 4) + y**2 assert e.as_sum(n, method="left").expand() == \ y**2 + y + Rational(1, 3) - y/n - 1/(2*n) + 1/(6*n**2) assert e.as_sum(10, method="left", evaluate=False).has(Sum) def test_as_sum_right(): e = Integral((x + y)**2, (x, 0, 1)) assert e.as_sum(1, method="right").expand() == 1 + 2*y + y**2 assert e.as_sum(2, method="right").expand() == Rational(5, 8) + y*Rational(3, 2) + y**2 assert e.as_sum(3, method="right").expand() == Rational(14, 27) + y*Rational(4, 3) + y**2 assert e.as_sum(4, method="right").expand() == Rational(15, 32) + y*Rational(5, 4) + y**2 assert e.as_sum(n, method="right").expand() == \ y**2 + y + Rational(1, 3) + y/n + 1/(2*n) + 1/(6*n**2) def test_as_sum_trapezoid(): e = Integral((x + y)**2, (x, 0, 1)) assert e.as_sum(1, method="trapezoid").expand() == y**2 + y + S.Half assert e.as_sum(2, method="trapezoid").expand() == y**2 + y + Rational(3, 8) assert e.as_sum(3, method="trapezoid").expand() == y**2 + y + Rational(19, 54) assert e.as_sum(4, method="trapezoid").expand() == y**2 + y + Rational(11, 32) assert e.as_sum(n, method="trapezoid").expand() == \ y**2 + y + Rational(1, 3) + 1/(6*n**2) assert Integral(sign(x), (x, 0, 1)).as_sum(1, 'trapezoid') == S.Half def test_as_sum_raises(): e = Integral((x + y)**2, (x, 0, 1)) raises(ValueError, lambda: e.as_sum(-1)) raises(ValueError, lambda: e.as_sum(0)) raises(ValueError, lambda: Integral(x).as_sum(3)) raises(ValueError, lambda: e.as_sum(oo)) raises(ValueError, lambda: e.as_sum(3, method='xxxx2')) def test_nested_doit(): e = Integral(Integral(x, x), x) f = Integral(x, x, x) assert e.doit() == f.doit() def test_issue_4665(): # Allow only upper or lower limit evaluation e = Integral(x**2, (x, None, 1)) f = Integral(x**2, (x, 1, None)) assert e.doit() == Rational(1, 3) assert f.doit() == Rational(-1, 3) assert Integral(x*y, (x, None, y)).subs(y, t) == Integral(x*t, (x, None, t)) assert Integral(x*y, (x, y, None)).subs(y, t) == Integral(x*t, (x, t, None)) assert integrate(x**2, (x, None, 1)) == Rational(1, 3) assert integrate(x**2, (x, 1, None)) == Rational(-1, 3) assert integrate("x**2", ("x", "1", None)) == Rational(-1, 3) def test_integral_reconstruct(): e = Integral(x**2, (x, -1, 1)) assert e == Integral(*e.args) def test_doit_integrals(): e = Integral(Integral(2*x), (x, 0, 1)) assert e.doit() == Rational(1, 3) assert e.doit(deep=False) == Rational(1, 3) f = Function('f') # doesn't matter if the integral can't be performed assert Integral(f(x), (x, 1, 1)).doit() == 0 # doesn't matter if the limits can't be evaluated assert Integral(0, (x, 1, Integral(f(x), x))).doit() == 0 assert Integral(x, (a, 0)).doit() == 0 limits = ((a, 1, exp(x)), (x, 0)) assert Integral(a, *limits).doit() == Rational(1, 4) assert Integral(a, *list(reversed(limits))).doit() == 0 def test_issue_4884(): assert integrate(sqrt(x)*(1 + x)) == \ Piecewise( (2*sqrt(x)*(x + 1)**2/5 - 2*sqrt(x)*(x + 1)/15 - 4*sqrt(x)/15, Abs(x + 1) > 1), (2*I*sqrt(-x)*(x + 1)**2/5 - 2*I*sqrt(-x)*(x + 1)/15 - 4*I*sqrt(-x)/15, True)) assert integrate(x**x*(1 + log(x))) == x**x def test_issue_18153(): assert integrate(x**n*log(x),x) == \ Piecewise( (n*x*x**n*log(x)/(n**2 + 2*n + 1) + x*x**n*log(x)/(n**2 + 2*n + 1) - x*x**n/(n**2 + 2*n + 1) , Ne(n, -1)), (log(x)**2/2, True) ) def test_is_number(): from sympy.abc import x, y, z from sympy import cos, sin assert Integral(x).is_number is False assert Integral(1, x).is_number is False assert Integral(1, (x, 1)).is_number is True assert Integral(1, (x, 1, 2)).is_number is True assert Integral(1, (x, 1, y)).is_number is False assert Integral(1, (x, y)).is_number is False assert Integral(x, y).is_number is False assert Integral(x, (y, 1, x)).is_number is False assert Integral(x, (y, 1, 2)).is_number is False assert Integral(x, (x, 1, 2)).is_number is True # `foo.is_number` should always be equivalent to `not foo.free_symbols` # in each of these cases, there are pseudo-free symbols i = Integral(x, (y, 1, 1)) assert i.is_number is False and i.n() == 0 i = Integral(x, (y, z, z)) assert i.is_number is False and i.n() == 0 i = Integral(1, (y, z, z + 2)) assert i.is_number is False and i.n() == 2 assert Integral(x*y, (x, 1, 2), (y, 1, 3)).is_number is True assert Integral(x*y, (x, 1, 2), (y, 1, z)).is_number is False assert Integral(x, (x, 1)).is_number is True assert Integral(x, (x, 1, Integral(y, (y, 1, 2)))).is_number is True assert Integral(Sum(z, (z, 1, 2)), (x, 1, 2)).is_number is True # it is possible to get a false negative if the integrand is # actually an unsimplified zero, but this is true of is_number in general. assert Integral(sin(x)**2 + cos(x)**2 - 1, x).is_number is False assert Integral(f(x), (x, 0, 1)).is_number is True def test_symbols(): from sympy.abc import x, y, z assert Integral(0, x).free_symbols == {x} assert Integral(x).free_symbols == {x} assert Integral(x, (x, None, y)).free_symbols == {y} assert Integral(x, (x, y, None)).free_symbols == {y} assert Integral(x, (x, 1, y)).free_symbols == {y} assert Integral(x, (x, y, 1)).free_symbols == {y} assert Integral(x, (x, x, y)).free_symbols == {x, y} assert Integral(x, x, y).free_symbols == {x, y} assert Integral(x, (x, 1, 2)).free_symbols == set() assert Integral(x, (y, 1, 2)).free_symbols == {x} # pseudo-free in this case assert Integral(x, (y, z, z)).free_symbols == {x, z} assert Integral(x, (y, 1, 2), (y, None, None)).free_symbols == {x, y} assert Integral(x, (y, 1, 2), (x, 1, y)).free_symbols == {y} assert Integral(2, (y, 1, 2), (y, 1, x), (x, 1, 2)).free_symbols == set() assert Integral(2, (y, x, 2), (y, 1, x), (x, 1, 2)).free_symbols == set() assert Integral(2, (x, 1, 2), (y, x, 2), (y, 1, 2)).free_symbols == \ {x} def test_is_zero(): from sympy.abc import x, m assert Integral(0, (x, 1, x)).is_zero assert Integral(1, (x, 1, 1)).is_zero assert Integral(1, (x, 1, 2), (y, 2)).is_zero is False assert Integral(x, (m, 0)).is_zero assert Integral(x + m, (m, 0)).is_zero is None i = Integral(m, (m, 1, exp(x)), (x, 0)) assert i.is_zero is None assert Integral(m, (x, 0), (m, 1, exp(x))).is_zero is True assert Integral(x, (x, oo, oo)).is_zero # issue 8171 assert Integral(x, (x, -oo, -oo)).is_zero # this is zero but is beyond the scope of what is_zero # should be doing assert Integral(sin(x), (x, 0, 2*pi)).is_zero is None def test_series(): from sympy.abc import x i = Integral(cos(x), (x, x)) e = i.lseries(x) assert i.nseries(x, n=8).removeO() == Add(*[next(e) for j in range(4)]) def test_trig_nonelementary_integrals(): x = Symbol('x') assert integrate((1 + sin(x))/x, x) == log(x) + Si(x) # next one comes out as log(x) + log(x**2)/2 + Ci(x) # so not hardcoding this log ugliness assert integrate((cos(x) + 2)/x, x).has(Ci) def test_issue_4403(): x = Symbol('x') y = Symbol('y') z = Symbol('z', positive=True) assert integrate(sqrt(x**2 + z**2), x) == \ z**2*asinh(x/z)/2 + x*sqrt(x**2 + z**2)/2 assert integrate(sqrt(x**2 - z**2), x) == \ -z**2*acosh(x/z)/2 + x*sqrt(x**2 - z**2)/2 x = Symbol('x', real=True) y = Symbol('y', positive=True) assert integrate(1/(x**2 + y**2)**S('3/2'), x) == \ x/(y**2*sqrt(x**2 + y**2)) # If y is real and nonzero, we get x*Abs(y)/(y**3*sqrt(x**2 + y**2)), # which results from sqrt(1 + x**2/y**2) = sqrt(x**2 + y**2)/|y|. def test_issue_4403_2(): assert integrate(sqrt(-x**2 - 4), x) == \ -2*atan(x/sqrt(-4 - x**2)) + x*sqrt(-4 - x**2)/2 def test_issue_4100(): R = Symbol('R', positive=True) assert integrate(sqrt(R**2 - x**2), (x, 0, R)) == pi*R**2/4 def test_issue_5167(): from sympy.abc import w, x, y, z f = Function('f') assert Integral(Integral(f(x), x), x) == Integral(f(x), x, x) assert Integral(f(x)).args == (f(x), Tuple(x)) assert Integral(Integral(f(x))).args == (f(x), Tuple(x), Tuple(x)) assert Integral(Integral(f(x)), y).args == (f(x), Tuple(x), Tuple(y)) assert Integral(Integral(f(x), z), y).args == (f(x), Tuple(z), Tuple(y)) assert Integral(Integral(Integral(f(x), x), y), z).args == \ (f(x), Tuple(x), Tuple(y), Tuple(z)) assert integrate(Integral(f(x), x), x) == Integral(f(x), x, x) assert integrate(Integral(f(x), y), x) == y*Integral(f(x), x) assert integrate(Integral(f(x), x), y) in [Integral(y*f(x), x), y*Integral(f(x), x)] assert integrate(Integral(2, x), x) == x**2 assert integrate(Integral(2, x), y) == 2*x*y # don't re-order given limits assert Integral(1, x, y).args != Integral(1, y, x).args # do as many as possible assert Integral(f(x), y, x, y, x).doit() == y**2*Integral(f(x), x, x)/2 assert Integral(f(x), (x, 1, 2), (w, 1, x), (z, 1, y)).doit() == \ y*(x - 1)*Integral(f(x), (x, 1, 2)) - (x - 1)*Integral(f(x), (x, 1, 2)) def test_issue_4890(): z = Symbol('z', positive=True) assert integrate(exp(-log(x)**2), x) == \ sqrt(pi)*exp(Rational(1, 4))*erf(log(x) - S.Half)/2 assert integrate(exp(log(x)**2), x) == \ sqrt(pi)*exp(Rational(-1, 4))*erfi(log(x)+S.Half)/2 assert integrate(exp(-z*log(x)**2), x) == \ sqrt(pi)*exp(1/(4*z))*erf(sqrt(z)*log(x) - 1/(2*sqrt(z)))/(2*sqrt(z)) def test_issue_4551(): assert not integrate(1/(x*sqrt(1 - x**2)), x).has(Integral) def test_issue_4376(): n = Symbol('n', integer=True, positive=True) assert simplify(integrate(n*(x**(1/n) - 1), (x, 0, S.Half)) - (n**2 - 2**(1/n)*n**2 - n*2**(1/n))/(2**(1 + 1/n) + n*2**(1 + 1/n))) == 0 def test_issue_4517(): assert integrate((sqrt(x) - x**3)/x**Rational(1, 3), x) == \ 6*x**Rational(7, 6)/7 - 3*x**Rational(11, 3)/11 def test_issue_4527(): k, m = symbols('k m', integer=True) assert integrate(sin(k*x)*sin(m*x), (x, 0, pi)).simplify() == \ Piecewise((0, Eq(k, 0) | Eq(m, 0)), (-pi/2, Eq(k, -m) | (Eq(k, 0) & Eq(m, 0))), (pi/2, Eq(k, m) | (Eq(k, 0) & Eq(m, 0))), (0, True)) # Should be possible to further simplify to: # Piecewise( # (0, Eq(k, 0) | Eq(m, 0)), # (-pi/2, Eq(k, -m)), # (pi/2, Eq(k, m)), # (0, True)) assert integrate(sin(k*x)*sin(m*x), (x,)) == Piecewise( (0, And(Eq(k, 0), Eq(m, 0))), (-x*sin(m*x)**2/2 - x*cos(m*x)**2/2 + sin(m*x)*cos(m*x)/(2*m), Eq(k, -m)), (x*sin(m*x)**2/2 + x*cos(m*x)**2/2 - sin(m*x)*cos(m*x)/(2*m), Eq(k, m)), (m*sin(k*x)*cos(m*x)/(k**2 - m**2) - k*sin(m*x)*cos(k*x)/(k**2 - m**2), True)) def test_issue_4199(): ypos = Symbol('y', positive=True) # TODO: Remove conds='none' below, let the assumption take care of it. assert integrate(exp(-I*2*pi*ypos*x)*x, (x, -oo, oo), conds='none') == \ Integral(exp(-I*2*pi*ypos*x)*x, (x, -oo, oo)) @slow def test_issue_3940(): a, b, c, d = symbols('a:d', positive=True, finite=True) assert integrate(exp(-x**2 + I*c*x), x) == \ -sqrt(pi)*exp(-c**2/4)*erf(I*c/2 - x)/2 assert integrate(exp(a*x**2 + b*x + c), x) == \ sqrt(pi)*exp(c)*exp(-b**2/(4*a))*erfi(sqrt(a)*x + b/(2*sqrt(a)))/(2*sqrt(a)) from sympy import expand_mul from sympy.abc import k assert expand_mul(integrate(exp(-x**2)*exp(I*k*x), (x, -oo, oo))) == \ sqrt(pi)*exp(-k**2/4) a, d = symbols('a d', positive=True) assert expand_mul(integrate(exp(-a*x**2 + 2*d*x), (x, -oo, oo))) == \ sqrt(pi)*exp(d**2/a)/sqrt(a) def test_issue_5413(): # Note that this is not the same as testing ratint() because integrate() # pulls out the coefficient. assert integrate(-a/(a**2 + x**2), x) == I*log(-I*a + x)/2 - I*log(I*a + x)/2 def test_issue_4892a(): A, z = symbols('A z') c = Symbol('c', nonzero=True) P1 = -A*exp(-z) P2 = -A/(c*t)*(sin(x)**2 + cos(y)**2) h1 = -sin(x)**2 - cos(y)**2 h2 = -sin(x)**2 + sin(y)**2 - 1 # there is still some non-deterministic behavior in integrate # or trigsimp which permits one of the following assert integrate(c*(P2 - P1), t) in [ c*(-A*(-h1)*log(c*t)/c + A*t*exp(-z)), c*(-A*(-h2)*log(c*t)/c + A*t*exp(-z)), c*( A* h1 *log(c*t)/c + A*t*exp(-z)), c*( A* h2 *log(c*t)/c + A*t*exp(-z)), (A*c*t - A*(-h1)*log(t)*exp(z))*exp(-z), (A*c*t - A*(-h2)*log(t)*exp(z))*exp(-z), ] def test_issue_4892b(): # Issues relating to issue 4596 are making the actual result of this hard # to test. The answer should be something like # # (-sin(y) + sqrt(-72 + 48*cos(y) - 8*cos(y)**2)/2)*log(x + sqrt(-72 + # 48*cos(y) - 8*cos(y)**2)/(2*(3 - cos(y)))) + (-sin(y) - sqrt(-72 + # 48*cos(y) - 8*cos(y)**2)/2)*log(x - sqrt(-72 + 48*cos(y) - # 8*cos(y)**2)/(2*(3 - cos(y)))) + x**2*sin(y)/2 + 2*x*cos(y) expr = (sin(y)*x**3 + 2*cos(y)*x**2 + 12)/(x**2 + 2) assert trigsimp(factor(integrate(expr, x).diff(x) - expr)) == 0 def test_issue_5178(): assert integrate(sin(x)*f(y, z), (x, 0, pi), (y, 0, pi), (z, 0, pi)) == \ 2*Integral(f(y, z), (y, 0, pi), (z, 0, pi)) def test_integrate_series(): f = sin(x).series(x, 0, 10) g = x**2/2 - x**4/24 + x**6/720 - x**8/40320 + x**10/3628800 + O(x**11) assert integrate(f, x) == g assert diff(integrate(f, x), x) == f assert integrate(O(x**5), x) == O(x**6) def test_atom_bug(): from sympy import meijerg from sympy.integrals.heurisch import heurisch assert heurisch(meijerg([], [], [1], [], x), x) is None def test_limit_bug(): z = Symbol('z', zero=False) assert integrate(sin(x*y*z), (x, 0, pi), (y, 0, pi)).together() == \ (log(z) - Ci(pi**2*z) + EulerGamma + 2*log(pi))/z def test_issue_4703(): g = Function('g') assert integrate(exp(x)*g(x), x).has(Integral) def test_issue_1888(): f = Function('f') assert integrate(f(x).diff(x)**2, x).has(Integral) # The following tests work using meijerint. def test_issue_3558(): from sympy import Si assert integrate(cos(x*y), (x, -pi/2, pi/2), (y, 0, pi)) == 2*Si(pi**2/2) def test_issue_4422(): assert integrate(1/sqrt(16 + 4*x**2), x) == asinh(x/2) / 2 def test_issue_4493(): from sympy import simplify assert simplify(integrate(x*sqrt(1 + 2*x), x)) == \ sqrt(2*x + 1)*(6*x**2 + x - 1)/15 def test_issue_4737(): assert integrate(sin(x)/x, (x, -oo, oo)) == pi assert integrate(sin(x)/x, (x, 0, oo)) == pi/2 assert integrate(sin(x)/x, x) == Si(x) def test_issue_4992(): # Note: psi in _check_antecedents becomes NaN. from sympy import simplify, expand_func, polygamma, gamma a = Symbol('a', positive=True) assert simplify(expand_func(integrate(exp(-x)*log(x)*x**a, (x, 0, oo)))) == \ (a*polygamma(0, a) + 1)*gamma(a) def test_issue_4487(): from sympy import lowergamma, simplify assert simplify(integrate(exp(-x)*x**y, x)) == lowergamma(y + 1, x) def test_issue_4215(): x = Symbol("x") assert integrate(1/(x**2), (x, -1, 1)) is oo def test_issue_4400(): n = Symbol('n', integer=True, positive=True) assert integrate((x**n)*log(x), x) == \ n*x*x**n*log(x)/(n**2 + 2*n + 1) + x*x**n*log(x)/(n**2 + 2*n + 1) - \ x*x**n/(n**2 + 2*n + 1) def test_issue_6253(): # Note: this used to raise NotImplementedError # Note: psi in _check_antecedents becomes NaN. assert integrate((sqrt(1 - x) + sqrt(1 + x))**2/x, x, meijerg=True) == \ Integral((sqrt(-x + 1) + sqrt(x + 1))**2/x, x) def test_issue_4153(): assert integrate(1/(1 + x + y + z), (x, 0, 1), (y, 0, 1), (z, 0, 1)) in [ -12*log(3) - 3*log(6)/2 + 3*log(8)/2 + 5*log(2) + 7*log(4), 6*log(2) + 8*log(4) - 27*log(3)/2, 22*log(2) - 27*log(3)/2, -12*log(3) - 3*log(6)/2 + 47*log(2)/2] def test_issue_4326(): R, b, h = symbols('R b h') # It doesn't matter if we can do the integral. Just make sure the result # doesn't contain nan. This is really a test against _eval_interval. e = integrate(((h*(x - R + b))/b)*sqrt(R**2 - x**2), (x, R - b, R)) assert not e.has(nan) # See that it evaluates assert not e.has(Integral) def test_powers(): assert integrate(2**x + 3**x, x) == 2**x/log(2) + 3**x/log(3) def test_manual_option(): raises(ValueError, lambda: integrate(1/x, x, manual=True, meijerg=True)) # an example of a function that manual integration cannot handle assert integrate(log(1+x)/x, (x, 0, 1), manual=True).has(Integral) def test_meijerg_option(): raises(ValueError, lambda: integrate(1/x, x, meijerg=True, risch=True)) # an example of a function that meijerg integration cannot handle assert integrate(tan(x), x, meijerg=True) == Integral(tan(x), x) def test_risch_option(): # risch=True only allowed on indefinite integrals raises(ValueError, lambda: integrate(1/log(x), (x, 0, oo), risch=True)) assert integrate(exp(-x**2), x, risch=True) == NonElementaryIntegral(exp(-x**2), x) assert integrate(log(1/x)*y, x, y, risch=True) == y**2*(x*log(1/x)/2 + x/2) assert integrate(erf(x), x, risch=True) == Integral(erf(x), x) # TODO: How to test risch=False? def test_heurisch_option(): raises(ValueError, lambda: integrate(1/x, x, risch=True, heurisch=True)) # an integral that heurisch can handle assert integrate(exp(x**2), x, heurisch=True) == sqrt(pi)*erfi(x)/2 # an integral that heurisch currently cannot handle assert integrate(exp(x)/x, x, heurisch=True) == Integral(exp(x)/x, x) # an integral where heurisch currently hangs, issue 15471 assert integrate(log(x)*cos(log(x))/x**Rational(3, 4), x, heurisch=False) == ( -128*x**Rational(1, 4)*sin(log(x))/289 + 240*x**Rational(1, 4)*cos(log(x))/289 + (16*x**Rational(1, 4)*sin(log(x))/17 + 4*x**Rational(1, 4)*cos(log(x))/17)*log(x)) def test_issue_6828(): f = 1/(1.08*x**2 - 4.3) g = integrate(f, x).diff(x) assert verify_numerically(f, g, tol=1e-12) def test_issue_4803(): x_max = Symbol("x_max") assert integrate(y/pi*exp(-(x_max - x)/cos(a)), x) == \ y*exp((x - x_max)/cos(a))*cos(a)/pi def test_issue_4234(): assert integrate(1/sqrt(1 + tan(x)**2)) == tan(x)/sqrt(1 + tan(x)**2) def test_issue_4492(): assert simplify(integrate(x**2 * sqrt(5 - x**2), x)) == Piecewise( (I*(2*x**5 - 15*x**3 + 25*x - 25*sqrt(x**2 - 5)*acosh(sqrt(5)*x/5)) / (8*sqrt(x**2 - 5)), 1 < Abs(x**2)/5), ((-2*x**5 + 15*x**3 - 25*x + 25*sqrt(-x**2 + 5)*asin(sqrt(5)*x/5)) / (8*sqrt(-x**2 + 5)), True)) def test_issue_2708(): # This test needs to use an integration function that can # not be evaluated in closed form. Update as needed. f = 1/(a + z + log(z)) integral_f = NonElementaryIntegral(f, (z, 2, 3)) assert Integral(f, (z, 2, 3)).doit() == integral_f assert integrate(f + exp(z), (z, 2, 3)) == integral_f - exp(2) + exp(3) assert integrate(2*f + exp(z), (z, 2, 3)) == \ 2*integral_f - exp(2) + exp(3) assert integrate(exp(1.2*n*s*z*(-t + z)/t), (z, 0, x)) == \ NonElementaryIntegral(exp(-1.2*n*s*z)*exp(1.2*n*s*z**2/t), (z, 0, x)) def test_issue_2884(): f = (4.000002016020*x + 4.000002016020*y + 4.000006024032)*exp(10.0*x) e = integrate(f, (x, 0.1, 0.2)) assert str(e) == '1.86831064982608*y + 2.16387491480008' def test_issue_8368(): assert integrate(exp(-s*x)*cosh(x), (x, 0, oo)) == \ Piecewise( ( pi*Piecewise( ( -s/(pi*(-s**2 + 1)), Abs(s**2) < 1), ( 1/(pi*s*(1 - 1/s**2)), Abs(s**(-2)) < 1), ( meijerg( ((S.Half,), (0, 0)), ((0, S.Half), (0,)), polar_lift(s)**2), True) ), And( Abs(periodic_argument(polar_lift(s)**2, oo)) < pi, cos(Abs(periodic_argument(polar_lift(s)**2, oo))/2)*sqrt(Abs(s**2)) - 1 > 0, Ne(s**2, 1)) ), ( Integral(exp(-s*x)*cosh(x), (x, 0, oo)), True)) assert integrate(exp(-s*x)*sinh(x), (x, 0, oo)) == \ Piecewise( ( -1/(s + 1)/2 - 1/(-s + 1)/2, And( Ne(1/s, 1), Abs(periodic_argument(s, oo)) < pi/2, Abs(periodic_argument(s, oo)) <= pi/2, cos(Abs(periodic_argument(s, oo)))*Abs(s) - 1 > 0)), ( Integral(exp(-s*x)*sinh(x), (x, 0, oo)), True)) def test_issue_8901(): assert integrate(sinh(1.0*x)) == 1.0*cosh(1.0*x) assert integrate(tanh(1.0*x)) == 1.0*x - 1.0*log(tanh(1.0*x) + 1) assert integrate(tanh(x)) == x - log(tanh(x) + 1) @slow def test_issue_8945(): assert integrate(sin(x)**3/x, (x, 0, 1)) == -Si(3)/4 + 3*Si(1)/4 assert integrate(sin(x)**3/x, (x, 0, oo)) == pi/4 assert integrate(cos(x)**2/x**2, x) == -Si(2*x) - cos(2*x)/(2*x) - 1/(2*x) @slow def test_issue_7130(): if ON_TRAVIS: skip("Too slow for travis.") i, L, a, b = symbols('i L a b') integrand = (cos(pi*i*x/L)**2 / (a + b*x)).rewrite(exp) assert x not in integrate(integrand, (x, 0, L)).free_symbols def test_issue_10567(): a, b, c, t = symbols('a b c t') vt = Matrix([a*t, b, c]) assert integrate(vt, t) == Integral(vt, t).doit() assert integrate(vt, t) == Matrix([[a*t**2/2], [b*t], [c*t]]) def test_issue_11856(): t = symbols('t') assert integrate(sinc(pi*t), t) == Si(pi*t)/pi @slow def test_issue_11876(): assert integrate(sqrt(log(1/x)), (x, 0, 1)) == sqrt(pi)/2 def test_issue_4950(): assert integrate((-60*exp(x) - 19.2*exp(4*x))*exp(4*x), x) ==\ -2.4*exp(8*x) - 12.0*exp(5*x) def test_issue_4968(): assert integrate(sin(log(x**2))) == x*sin(log(x**2))/5 - 2*x*cos(log(x**2))/5 def test_singularities(): assert integrate(1/x**2, (x, -oo, oo)) is oo assert integrate(1/x**2, (x, -1, 1)) is oo assert integrate(1/(x - 1)**2, (x, -2, 2)) is oo assert integrate(1/x**2, (x, 1, -1)) is -oo assert integrate(1/(x - 1)**2, (x, 2, -2)) is -oo def test_issue_12645(): x, y = symbols('x y', real=True) assert (integrate(sin(x*x*x + y*y), (x, -sqrt(pi - y*y), sqrt(pi - y*y)), (y, -sqrt(pi), sqrt(pi))) == Integral(sin(x**3 + y**2), (x, -sqrt(-y**2 + pi), sqrt(-y**2 + pi)), (y, -sqrt(pi), sqrt(pi)))) def test_issue_12677(): assert integrate(sin(x) / (cos(x)**3) , (x, 0, pi/6)) == Rational(1,6) def test_issue_14078(): assert integrate((cos(3*x)-cos(x))/x, (x, 0, oo)) == -log(3) def test_issue_14064(): assert integrate(1/cosh(x), (x, 0, oo)) == pi/2 def test_issue_14027(): assert integrate(1/(1 + exp(x - S.Half)/(1 + exp(x))), x) == \ x - exp(S.Half)*log(exp(x) + exp(S.Half)/(1 + exp(S.Half)))/(exp(S.Half) + E) def test_issue_8170(): assert integrate(tan(x), (x, 0, pi/2)) is S.Infinity def test_issue_8440_14040(): assert integrate(1/x, (x, -1, 1)) is S.NaN assert integrate(1/(x + 1), (x, -2, 3)) is S.NaN def test_issue_14096(): assert integrate(1/(x + y)**2, (x, 0, 1)) == -1/(y + 1) + 1/y assert integrate(1/(1 + x + y + z)**2, (x, 0, 1), (y, 0, 1), (z, 0, 1)) == \ -4*log(4) - 6*log(2) + 9*log(3) def test_issue_14144(): assert Abs(integrate(1/sqrt(1 - x**3), (x, 0, 1)).n() - 1.402182) < 1e-6 assert Abs(integrate(sqrt(1 - x**3), (x, 0, 1)).n() - 0.841309) < 1e-6 def test_issue_14375(): # This raised a TypeError. The antiderivative has exp_polar, which # may be possible to unpolarify, so the exact output is not asserted here. assert integrate(exp(I*x)*log(x), x).has(Ei) def test_issue_14437(): f = Function('f')(x, y, z) assert integrate(f, (x, 0, 1), (y, 0, 2), (z, 0, 3)) == \ Integral(f, (x, 0, 1), (y, 0, 2), (z, 0, 3)) def test_issue_14470(): assert integrate(1/sqrt(exp(x) + 1), x) == \ log(-1 + 1/sqrt(exp(x) + 1)) - log(1 + 1/sqrt(exp(x) + 1)) def test_issue_14877(): f = exp(1 - exp(x**2)*x + 2*x**2)*(2*x**3 + x)/(1 - exp(x**2)*x)**2 assert integrate(f, x) == \ -exp(2*x**2 - x*exp(x**2) + 1)/(x*exp(3*x**2) - exp(2*x**2)) def test_issue_14782(): f = sqrt(-x**2 + 1)*(-x**2 + x) assert integrate(f, [x, -1, 1]) == - pi / 8 @slow def test_issue_14782_slow(): f = sqrt(-x**2 + 1)*(-x**2 + x) assert integrate(f, [x, 0, 1]) == S.One / 3 - pi / 16 def test_issue_12081(): f = x**(Rational(-3, 2))*exp(-x) assert integrate(f, [x, 0, oo]) is oo def test_issue_15285(): y = 1/x - 1 f = 4*y*exp(-2*y)/x**2 assert integrate(f, [x, 0, 1]) == 1 def test_issue_15432(): assert integrate(x**n * exp(-x) * log(x), (x, 0, oo)).gammasimp() == Piecewise( (gamma(n + 1)*polygamma(0, n) + gamma(n + 1)/n, re(n) + 1 > 0), (Integral(x**n*exp(-x)*log(x), (x, 0, oo)), True)) def test_issue_15124(): omega = IndexedBase('omega') m, p = symbols('m p', cls=Idx) assert integrate(exp(x*I*(omega[m] + omega[p])), x, conds='none') == \ -I*exp(I*x*omega[m])*exp(I*x*omega[p])/(omega[m] + omega[p]) def test_issue_15218(): with warns_deprecated_sympy(): Integral(Eq(x, y)) with warns_deprecated_sympy(): assert Integral(Eq(x, y), x) == Eq(Integral(x, x), Integral(y, x)) with warns_deprecated_sympy(): assert Integral(Eq(x, y), x).doit() == Eq(x**2/2, x*y) with warns_deprecated_sympy(): assert Eq(x, y).integrate(x) == Eq(x**2/2, x*y) # These are not deprecated because they are definite integrals assert integrate(Eq(x, y), (x, 0, 1)) == Eq(S.Half, y) assert Eq(x, y).integrate((x, 0, 1)) == Eq(S.Half, y) def test_issue_15292(): res = integrate(exp(-x**2*cos(2*t)) * cos(x**2*sin(2*t)), (x, 0, oo)) assert isinstance(res, Piecewise) assert gammasimp((res - sqrt(pi)/2 * cos(t)).subs(t, pi/6)) == 0 def test_issue_4514(): assert integrate(sin(2*x)/sin(x), x) == 2*sin(x) def test_issue_15457(): x, a, b = symbols('x a b', real=True) definite = integrate(exp(Abs(x-2)), (x, a, b)) indefinite = integrate(exp(Abs(x-2)), x) assert definite.subs({a: 1, b: 3}) == -2 + 2*E assert indefinite.subs(x, 3) - indefinite.subs(x, 1) == -2 + 2*E assert definite.subs({a: -3, b: -1}) == -exp(3) + exp(5) assert indefinite.subs(x, -1) - indefinite.subs(x, -3) == -exp(3) + exp(5) def test_issue_15431(): assert integrate(x*exp(x)*log(x), x) == \ (x*exp(x) - exp(x))*log(x) - exp(x) + Ei(x) def test_issue_15640_log_substitutions(): f = x/log(x) F = Ei(2*log(x)) assert integrate(f, x) == F and F.diff(x) == f f = x**3/log(x)**2 F = -x**4/log(x) + 4*Ei(4*log(x)) assert integrate(f, x) == F and F.diff(x) == f f = sqrt(log(x))/x**2 F = -sqrt(pi)*erfc(sqrt(log(x)))/2 - sqrt(log(x))/x assert integrate(f, x) == F and F.diff(x) == f def test_issue_15509(): from sympy.vector import CoordSys3D N = CoordSys3D('N') x = N.x assert integrate(cos(a*x + b), (x, x_1, x_2), heurisch=True) == Piecewise( (-sin(a*x_1 + b)/a + sin(a*x_2 + b)/a, (a > -oo) & (a < oo) & Ne(a, 0)), \ (-x_1*cos(b) + x_2*cos(b), True)) def test_issue_4311_fast(): x = symbols('x', real=True) assert integrate(x*abs(9-x**2), x) == Piecewise( (x**4/4 - 9*x**2/2, x <= -3), (-x**4/4 + 9*x**2/2 - Rational(81, 2), x <= 3), (x**4/4 - 9*x**2/2, True)) def test_integrate_with_complex_constants(): K = Symbol('K', real=True, positive=True) x = Symbol('x', real=True) m = Symbol('m', real=True) t = Symbol('t', real=True) assert integrate(exp(-I*K*x**2+m*x), x) == sqrt(I)*sqrt(pi)*exp(-I*m**2 /(4*K))*erfi((-2*I*K*x + m)/(2*sqrt(K)*sqrt(-I)))/(2*sqrt(K)) assert integrate(1/(1 + I*x**2), x) == (-I*(sqrt(-I)*log(x - I*sqrt(-I))/2 - sqrt(-I)*log(x + I*sqrt(-I))/2)) assert integrate(exp(-I*x**2), x) == sqrt(pi)*erf(sqrt(I)*x)/(2*sqrt(I)) assert integrate((1/(exp(I*t)-2)), t) == -t/2 - I*log(exp(I*t) - 2)/2 assert integrate((1/(exp(I*t)-2)), (t, 0, 2*pi)) == -pi def test_issue_14241(): x = Symbol('x') n = Symbol('n', positive=True, integer=True) assert integrate(n * x ** (n - 1) / (x + 1), x) == \ n**2*x**n*lerchphi(x*exp_polar(I*pi), 1, n)*gamma(n)/gamma(n + 1) def test_issue_13112(): assert integrate(sin(t)**2 / (5 - 4*cos(t)), [t, 0, 2*pi]) == pi / 4 def test_issue_14709b(): h = Symbol('h', positive=True) i = integrate(x*acos(1 - 2*x/h), (x, 0, h)) assert i == 5*h**2*pi/16 def test_issue_8614(): x = Symbol('x') t = Symbol('t') assert integrate(exp(t)/t, (t, -oo, x)) == Ei(x) assert integrate((exp(-x) - exp(-2*x))/x, (x, 0, oo)) == log(2) def test_issue_15494(): s = symbols('s', real=True, positive=True) integrand = (exp(s/2) - 2*exp(1.6*s) + exp(s))*exp(s) solution = integrate(integrand, s) assert solution != S.NaN # Not sure how to test this properly as it is a symbolic expression with floats # assert str(solution) == '0.666666666666667*exp(1.5*s) + 0.5*exp(2.0*s) - 0.769230769230769*exp(2.6*s)' # Maybe assert abs(solution.subs(s, 1) - (-3.67440080236188)) <= 1e-8 integrand = (exp(s/2) - 2*exp(S(8)/5*s) + exp(s))*exp(s) assert integrate(integrand, s) == -10*exp(13*s/5)/13 + 2*exp(3*s/2)/3 + exp(2*s)/2 def test_li_integral(): y = Symbol('y') assert Integral(li(y*x**2), x).doit() == Piecewise((x*li(x**2*y) - \ x*Ei(3*log(x**2*y)/2)/sqrt(x**2*y), Ne(y, 0)), (0, True)) def test_issue_17473(): x = Symbol('x') n = Symbol('n') assert integrate(sin(x**n), x) == \ x*x**n*gamma(S(1)/2 + 1/(2*n))*hyper((S(1)/2 + 1/(2*n),), (S(3)/2, S(3)/2 + 1/(2*n)), -x**(2*n)/4)/(2*n*gamma(S(3)/2 + 1/(2*n))) def test_issue_17671(): assert integrate(log(log(x)) / x**2, [x, 1, oo]) == -EulerGamma assert integrate(log(log(x)) / x**3, [x, 1, oo]) == -log(2)/2 - EulerGamma/2 assert integrate(log(log(x)) / x**10, [x, 1, oo]) == -2*log(3)/9 - EulerGamma/9 def test_issue_2975(): w = Symbol('w') C = Symbol('C') y = Symbol('y') assert integrate(1/(y**2+C)**(S(3)/2), (y, -w/2, w/2)) == w/(C**(S(3)/2)*sqrt(1 + w**2/(4*C))) def test_issue_7827(): x, n, M = symbols('x n M') N = Symbol('N', integer=True) assert integrate(summation(x*n, (n, 1, N)), x) == x**2*(N**2/4 + N/4) assert integrate(summation(x*sin(n), (n,1,N)), x) == \ Sum(x**2*sin(n)/2, (n, 1, N)) assert integrate(summation(sin(n*x), (n,1,N)), x) == \ Sum(Piecewise((-cos(n*x)/n, Ne(n, 0)), (0, True)), (n, 1, N)) assert integrate(integrate(summation(sin(n*x), (n,1,N)), x), x) == \ Piecewise((Sum(Piecewise((-sin(n*x)/n**2, Ne(n, 0)), (-x/n, True)), (n, 1, N)), (n > -oo) & (n < oo) & Ne(n, 0)), (0, True)) assert integrate(Sum(x, (n, 1, M)), x) == M*x**2/2 raises(ValueError, lambda: integrate(Sum(x, (x, y, n)), y)) raises(ValueError, lambda: integrate(Sum(x, (x, 1, n)), n)) raises(ValueError, lambda: integrate(Sum(x, (x, 1, y)), x)) def test_issue_4231(): f = (1 + 2*x + sqrt(x + log(x))*(1 + 3*x) + x**2)/(x*(x + sqrt(x + log(x)))*sqrt(x + log(x))) assert integrate(f, x) == 2*sqrt(x + log(x)) + 2*log(x + sqrt(x + log(x))) def test_issue_17841(): f = diff(1/(x**2+x+I), x) assert integrate(f, x) == 1/(x**2 + x + I) def test_issue_21034(): x = Symbol('x', real=True, nonzero=True) f1 = x*(-x**4/asin(5)**4 - x*sinh(x + log(asin(5))) + 5) f2 = (x + cosh(cos(4)))/(x*(x + 1/(12*x))) assert integrate(f1, x) == \ -x**6/(6*asin(5)**4) - x**2*cosh(x + log(asin(5))) + 5*x**2/2 + 2*x*sinh(x + log(asin(5))) - 2*cosh(x + log(asin(5))) assert integrate(f2, x) == \ log(x**2 + S(1)/12)/2 + 2*sqrt(3)*cosh(cos(4))*atan(2*sqrt(3)*x)
7abd87ae7e485b87667e51d551d9c35b6c930e45bc84dd00ac552880a914d5eb
from sympy.integrals.transforms import (mellin_transform, inverse_mellin_transform, laplace_transform, inverse_laplace_transform, fourier_transform, inverse_fourier_transform, sine_transform, inverse_sine_transform, cosine_transform, inverse_cosine_transform, hankel_transform, inverse_hankel_transform, LaplaceTransform, FourierTransform, SineTransform, CosineTransform, InverseLaplaceTransform, InverseFourierTransform, InverseSineTransform, InverseCosineTransform, IntegralTransformError) from sympy import ( gamma, exp, oo, Heaviside, symbols, Symbol, re, factorial, pi, arg, cos, S, Abs, And, sin, sqrt, I, log, tan, hyperexpand, meijerg, EulerGamma, erf, erfc, besselj, bessely, besseli, besselk, exp_polar, unpolarify, Function, expint, expand_mul, Rational, gammasimp, trigsimp, atan, sinh, cosh, Ne, periodic_argument, atan2) from sympy.testing.pytest import XFAIL, slow, skip, raises, warns_deprecated_sympy from sympy.matrices import Matrix, eye from sympy.abc import x, s, a, b, c, d nu, beta, rho = symbols('nu beta rho') def test_undefined_function(): from sympy import Function, MellinTransform f = Function('f') assert mellin_transform(f(x), x, s) == MellinTransform(f(x), x, s) assert mellin_transform(f(x) + exp(-x), x, s) == \ (MellinTransform(f(x), x, s) + gamma(s), (0, oo), True) assert laplace_transform(2*f(x), x, s) == 2*LaplaceTransform(f(x), x, s) # TODO test derivative and other rules when implemented def test_free_symbols(): from sympy import Function f = Function('f') assert mellin_transform(f(x), x, s).free_symbols == {s} assert mellin_transform(f(x)*a, x, s).free_symbols == {s, a} def test_as_integral(): from sympy import Function, Integral f = Function('f') assert mellin_transform(f(x), x, s).rewrite('Integral') == \ Integral(x**(s - 1)*f(x), (x, 0, oo)) assert fourier_transform(f(x), x, s).rewrite('Integral') == \ Integral(f(x)*exp(-2*I*pi*s*x), (x, -oo, oo)) assert laplace_transform(f(x), x, s).rewrite('Integral') == \ Integral(f(x)*exp(-s*x), (x, 0, oo)) assert str(2*pi*I*inverse_mellin_transform(f(s), s, x, (a, b)).rewrite('Integral')) \ == "Integral(f(s)/x**s, (s, _c - oo*I, _c + oo*I))" assert str(2*pi*I*inverse_laplace_transform(f(s), s, x).rewrite('Integral')) == \ "Integral(f(s)*exp(s*x), (s, _c - oo*I, _c + oo*I))" assert inverse_fourier_transform(f(s), s, x).rewrite('Integral') == \ Integral(f(s)*exp(2*I*pi*s*x), (s, -oo, oo)) # NOTE this is stuck in risch because meijerint cannot handle it @slow @XFAIL def test_mellin_transform_fail(): skip("Risch takes forever.") MT = mellin_transform bpos = symbols('b', positive=True) # bneg = symbols('b', negative=True) expr = (sqrt(x + b**2) + b)**a/sqrt(x + b**2) # TODO does not work with bneg, argument wrong. Needs changes to matching. assert MT(expr.subs(b, -bpos), x, s) == \ ((-1)**(a + 1)*2**(a + 2*s)*bpos**(a + 2*s - 1)*gamma(a + s) *gamma(1 - a - 2*s)/gamma(1 - s), (-re(a), -re(a)/2 + S.Half), True) expr = (sqrt(x + b**2) + b)**a assert MT(expr.subs(b, -bpos), x, s) == \ ( 2**(a + 2*s)*a*bpos**(a + 2*s)*gamma(-a - 2* s)*gamma(a + s)/gamma(-s + 1), (-re(a), -re(a)/2), True) # Test exponent 1: assert MT(expr.subs({b: -bpos, a: 1}), x, s) == \ (-bpos**(2*s + 1)*gamma(s)*gamma(-s - S.Half)/(2*sqrt(pi)), (-1, Rational(-1, 2)), True) def test_mellin_transform(): from sympy import Max, Min MT = mellin_transform bpos = symbols('b', positive=True) # 8.4.2 assert MT(x**nu*Heaviside(x - 1), x, s) == \ (-1/(nu + s), (-oo, -re(nu)), True) assert MT(x**nu*Heaviside(1 - x), x, s) == \ (1/(nu + s), (-re(nu), oo), True) assert MT((1 - x)**(beta - 1)*Heaviside(1 - x), x, s) == \ (gamma(beta)*gamma(s)/gamma(beta + s), (0, oo), re(beta) > 0) assert MT((x - 1)**(beta - 1)*Heaviside(x - 1), x, s) == \ (gamma(beta)*gamma(1 - beta - s)/gamma(1 - s), (-oo, -re(beta) + 1), re(beta) > 0) assert MT((1 + x)**(-rho), x, s) == \ (gamma(s)*gamma(rho - s)/gamma(rho), (0, re(rho)), True) # TODO also the conditions should be simplified, e.g. # And(re(rho) - 1 < 0, re(rho) < 1) should just be # re(rho) < 1 assert MT(abs(1 - x)**(-rho), x, s) == ( 2*sin(pi*rho/2)*gamma(1 - rho)* cos(pi*(rho/2 - s))*gamma(s)*gamma(rho-s)/pi, (0, re(rho)), And(re(rho) - 1 < 0, re(rho) < 1)) mt = MT((1 - x)**(beta - 1)*Heaviside(1 - x) + a*(x - 1)**(beta - 1)*Heaviside(x - 1), x, s) assert mt[1], mt[2] == ((0, -re(beta) + 1), re(beta) > 0) assert MT((x**a - b**a)/(x - b), x, s)[0] == \ pi*b**(a + s - 1)*sin(pi*a)/(sin(pi*s)*sin(pi*(a + s))) assert MT((x**a - bpos**a)/(x - bpos), x, s) == \ (pi*bpos**(a + s - 1)*sin(pi*a)/(sin(pi*s)*sin(pi*(a + s))), (Max(-re(a), 0), Min(1 - re(a), 1)), True) expr = (sqrt(x + b**2) + b)**a assert MT(expr.subs(b, bpos), x, s) == \ (-a*(2*bpos)**(a + 2*s)*gamma(s)*gamma(-a - 2*s)/gamma(-a - s + 1), (0, -re(a)/2), True) expr = (sqrt(x + b**2) + b)**a/sqrt(x + b**2) assert MT(expr.subs(b, bpos), x, s) == \ (2**(a + 2*s)*bpos**(a + 2*s - 1)*gamma(s) *gamma(1 - a - 2*s)/gamma(1 - a - s), (0, -re(a)/2 + S.Half), True) # 8.4.2 assert MT(exp(-x), x, s) == (gamma(s), (0, oo), True) assert MT(exp(-1/x), x, s) == (gamma(-s), (-oo, 0), True) # 8.4.5 assert MT(log(x)**4*Heaviside(1 - x), x, s) == (24/s**5, (0, oo), True) assert MT(log(x)**3*Heaviside(x - 1), x, s) == (6/s**4, (-oo, 0), True) assert MT(log(x + 1), x, s) == (pi/(s*sin(pi*s)), (-1, 0), True) assert MT(log(1/x + 1), x, s) == (pi/(s*sin(pi*s)), (0, 1), True) assert MT(log(abs(1 - x)), x, s) == (pi/(s*tan(pi*s)), (-1, 0), True) assert MT(log(abs(1 - 1/x)), x, s) == (pi/(s*tan(pi*s)), (0, 1), True) # 8.4.14 assert MT(erf(sqrt(x)), x, s) == \ (-gamma(s + S.Half)/(sqrt(pi)*s), (Rational(-1, 2), 0), True) @slow def test_mellin_transform2(): MT = mellin_transform # TODO we cannot currently do these (needs summation of 3F2(-1)) # this also implies that they cannot be written as a single g-function # (although this is possible) mt = MT(log(x)/(x + 1), x, s) assert mt[1:] == ((0, 1), True) assert not hyperexpand(mt[0], allow_hyper=True).has(meijerg) mt = MT(log(x)**2/(x + 1), x, s) assert mt[1:] == ((0, 1), True) assert not hyperexpand(mt[0], allow_hyper=True).has(meijerg) mt = MT(log(x)/(x + 1)**2, x, s) assert mt[1:] == ((0, 2), True) assert not hyperexpand(mt[0], allow_hyper=True).has(meijerg) @slow def test_mellin_transform_bessel(): from sympy import Max MT = mellin_transform # 8.4.19 assert MT(besselj(a, 2*sqrt(x)), x, s) == \ (gamma(a/2 + s)/gamma(a/2 - s + 1), (-re(a)/2, Rational(3, 4)), True) assert MT(sin(sqrt(x))*besselj(a, sqrt(x)), x, s) == \ (2**a*gamma(-2*s + S.Half)*gamma(a/2 + s + S.Half)/( gamma(-a/2 - s + 1)*gamma(a - 2*s + 1)), ( -re(a)/2 - S.Half, Rational(1, 4)), True) assert MT(cos(sqrt(x))*besselj(a, sqrt(x)), x, s) == \ (2**a*gamma(a/2 + s)*gamma(-2*s + S.Half)/( gamma(-a/2 - s + S.Half)*gamma(a - 2*s + 1)), ( -re(a)/2, Rational(1, 4)), True) assert MT(besselj(a, sqrt(x))**2, x, s) == \ (gamma(a + s)*gamma(S.Half - s) / (sqrt(pi)*gamma(1 - s)*gamma(1 + a - s)), (-re(a), S.Half), True) assert MT(besselj(a, sqrt(x))*besselj(-a, sqrt(x)), x, s) == \ (gamma(s)*gamma(S.Half - s) / (sqrt(pi)*gamma(1 - a - s)*gamma(1 + a - s)), (0, S.Half), True) # NOTE: prudnikov gives the strip below as (1/2 - re(a), 1). As far as # I can see this is wrong (since besselj(z) ~ 1/sqrt(z) for z large) assert MT(besselj(a - 1, sqrt(x))*besselj(a, sqrt(x)), x, s) == \ (gamma(1 - s)*gamma(a + s - S.Half) / (sqrt(pi)*gamma(Rational(3, 2) - s)*gamma(a - s + S.Half)), (S.Half - re(a), S.Half), True) assert MT(besselj(a, sqrt(x))*besselj(b, sqrt(x)), x, s) == \ (4**s*gamma(1 - 2*s)*gamma((a + b)/2 + s) / (gamma(1 - s + (b - a)/2)*gamma(1 - s + (a - b)/2) *gamma( 1 - s + (a + b)/2)), (-(re(a) + re(b))/2, S.Half), True) assert MT(besselj(a, sqrt(x))**2 + besselj(-a, sqrt(x))**2, x, s)[1:] == \ ((Max(re(a), -re(a)), S.Half), True) # Section 8.4.20 assert MT(bessely(a, 2*sqrt(x)), x, s) == \ (-cos(pi*(a/2 - s))*gamma(s - a/2)*gamma(s + a/2)/pi, (Max(-re(a)/2, re(a)/2), Rational(3, 4)), True) assert MT(sin(sqrt(x))*bessely(a, sqrt(x)), x, s) == \ (-4**s*sin(pi*(a/2 - s))*gamma(S.Half - 2*s) * gamma((1 - a)/2 + s)*gamma((1 + a)/2 + s) / (sqrt(pi)*gamma(1 - s - a/2)*gamma(1 - s + a/2)), (Max(-(re(a) + 1)/2, (re(a) - 1)/2), Rational(1, 4)), True) assert MT(cos(sqrt(x))*bessely(a, sqrt(x)), x, s) == \ (-4**s*cos(pi*(a/2 - s))*gamma(s - a/2)*gamma(s + a/2)*gamma(S.Half - 2*s) / (sqrt(pi)*gamma(S.Half - s - a/2)*gamma(S.Half - s + a/2)), (Max(-re(a)/2, re(a)/2), Rational(1, 4)), True) assert MT(besselj(a, sqrt(x))*bessely(a, sqrt(x)), x, s) == \ (-cos(pi*s)*gamma(s)*gamma(a + s)*gamma(S.Half - s) / (pi**S('3/2')*gamma(1 + a - s)), (Max(-re(a), 0), S.Half), True) assert MT(besselj(a, sqrt(x))*bessely(b, sqrt(x)), x, s) == \ (-4**s*cos(pi*(a/2 - b/2 + s))*gamma(1 - 2*s) * gamma(a/2 - b/2 + s)*gamma(a/2 + b/2 + s) / (pi*gamma(a/2 - b/2 - s + 1)*gamma(a/2 + b/2 - s + 1)), (Max((-re(a) + re(b))/2, (-re(a) - re(b))/2), S.Half), True) # NOTE bessely(a, sqrt(x))**2 and bessely(a, sqrt(x))*bessely(b, sqrt(x)) # are a mess (no matter what way you look at it ...) assert MT(bessely(a, sqrt(x))**2, x, s)[1:] == \ ((Max(-re(a), 0, re(a)), S.Half), True) # Section 8.4.22 # TODO we can't do any of these (delicate cancellation) # Section 8.4.23 assert MT(besselk(a, 2*sqrt(x)), x, s) == \ (gamma( s - a/2)*gamma(s + a/2)/2, (Max(-re(a)/2, re(a)/2), oo), True) assert MT(besselj(a, 2*sqrt(2*sqrt(x)))*besselk( a, 2*sqrt(2*sqrt(x))), x, s) == (4**(-s)*gamma(2*s)* gamma(a/2 + s)/(2*gamma(a/2 - s + 1)), (Max(0, -re(a)/2), oo), True) # TODO bessely(a, x)*besselk(a, x) is a mess assert MT(besseli(a, sqrt(x))*besselk(a, sqrt(x)), x, s) == \ (gamma(s)*gamma( a + s)*gamma(-s + S.Half)/(2*sqrt(pi)*gamma(a - s + 1)), (Max(-re(a), 0), S.Half), True) assert MT(besseli(b, sqrt(x))*besselk(a, sqrt(x)), x, s) == \ (2**(2*s - 1)*gamma(-2*s + 1)*gamma(-a/2 + b/2 + s)* \ gamma(a/2 + b/2 + s)/(gamma(-a/2 + b/2 - s + 1)* \ gamma(a/2 + b/2 - s + 1)), (Max(-re(a)/2 - re(b)/2, \ re(a)/2 - re(b)/2), S.Half), True) # TODO products of besselk are a mess mt = MT(exp(-x/2)*besselk(a, x/2), x, s) mt0 = gammasimp(trigsimp(gammasimp(mt[0].expand(func=True)))) assert mt0 == 2*pi**Rational(3, 2)*cos(pi*s)*gamma(-s + S.Half)/( (cos(2*pi*a) - cos(2*pi*s))*gamma(-a - s + 1)*gamma(a - s + 1)) assert mt[1:] == ((Max(-re(a), re(a)), oo), True) # TODO exp(x/2)*besselk(a, x/2) [etc] cannot currently be done # TODO various strange products of special orders @slow def test_expint(): from sympy import E1, expint, Max, re, lerchphi, Symbol, simplify, Si, Ci, Ei aneg = Symbol('a', negative=True) u = Symbol('u', polar=True) assert mellin_transform(E1(x), x, s) == (gamma(s)/s, (0, oo), True) assert inverse_mellin_transform(gamma(s)/s, s, x, (0, oo)).rewrite(expint).expand() == E1(x) assert mellin_transform(expint(a, x), x, s) == \ (gamma(s)/(a + s - 1), (Max(1 - re(a), 0), oo), True) # XXX IMT has hickups with complicated strips ... assert simplify(unpolarify( inverse_mellin_transform(gamma(s)/(aneg + s - 1), s, x, (1 - aneg, oo)).rewrite(expint).expand(func=True))) == \ expint(aneg, x) assert mellin_transform(Si(x), x, s) == \ (-2**s*sqrt(pi)*gamma(s/2 + S.Half)/( 2*s*gamma(-s/2 + 1)), (-1, 0), True) assert inverse_mellin_transform(-2**s*sqrt(pi)*gamma((s + 1)/2) /(2*s*gamma(-s/2 + 1)), s, x, (-1, 0)) \ == Si(x) assert mellin_transform(Ci(sqrt(x)), x, s) == \ (-2**(2*s - 1)*sqrt(pi)*gamma(s)/(s*gamma(-s + S.Half)), (0, 1), True) assert inverse_mellin_transform( -4**s*sqrt(pi)*gamma(s)/(2*s*gamma(-s + S.Half)), s, u, (0, 1)).expand() == Ci(sqrt(u)) # TODO LT of Si, Shi, Chi is a mess ... assert laplace_transform(Ci(x), x, s) == (-log(1 + s**2)/2/s, 0, True) assert laplace_transform(expint(a, x), x, s) == \ (lerchphi(s*exp_polar(I*pi), 1, a), 0, re(a) > S.Zero) assert laplace_transform(expint(1, x), x, s) == (log(s + 1)/s, 0, True) assert laplace_transform(expint(2, x), x, s) == \ ((s - log(s + 1))/s**2, 0, True) assert inverse_laplace_transform(-log(1 + s**2)/2/s, s, u).expand() == \ Heaviside(u)*Ci(u) assert inverse_laplace_transform(log(s + 1)/s, s, x).rewrite(expint) == \ Heaviside(x)*E1(x) assert inverse_laplace_transform((s - log(s + 1))/s**2, s, x).rewrite(expint).expand() == \ (expint(2, x)*Heaviside(x)).rewrite(Ei).rewrite(expint).expand() @slow def test_inverse_mellin_transform(): from sympy import (sin, simplify, Max, Min, expand, powsimp, exp_polar, cos, cot) IMT = inverse_mellin_transform assert IMT(gamma(s), s, x, (0, oo)) == exp(-x) assert IMT(gamma(-s), s, x, (-oo, 0)) == exp(-1/x) assert simplify(IMT(s/(2*s**2 - 2), s, x, (2, oo))) == \ (x**2 + 1)*Heaviside(1 - x)/(4*x) # test passing "None" assert IMT(1/(s**2 - 1), s, x, (-1, None)) == \ -x*Heaviside(-x + 1)/2 - Heaviside(x - 1)/(2*x) assert IMT(1/(s**2 - 1), s, x, (None, 1)) == \ -x*Heaviside(-x + 1)/2 - Heaviside(x - 1)/(2*x) # test expansion of sums assert IMT(gamma(s) + gamma(s - 1), s, x, (1, oo)) == (x + 1)*exp(-x)/x # test factorisation of polys r = symbols('r', real=True) assert IMT(1/(s**2 + 1), s, exp(-x), (None, oo) ).subs(x, r).rewrite(sin).simplify() \ == sin(r)*Heaviside(1 - exp(-r)) # test multiplicative substitution _a, _b = symbols('a b', positive=True) assert IMT(_b**(-s/_a)*factorial(s/_a)/s, s, x, (0, oo)) == exp(-_b*x**_a) assert IMT(factorial(_a/_b + s/_b)/(_a + s), s, x, (-_a, oo)) == x**_a*exp(-x**_b) def simp_pows(expr): return simplify(powsimp(expand_mul(expr, deep=False), force=True)).replace(exp_polar, exp) # Now test the inverses of all direct transforms tested above # Section 8.4.2 nu = symbols('nu', real=True) assert IMT(-1/(nu + s), s, x, (-oo, None)) == x**nu*Heaviside(x - 1) assert IMT(1/(nu + s), s, x, (None, oo)) == x**nu*Heaviside(1 - x) assert simp_pows(IMT(gamma(beta)*gamma(s)/gamma(s + beta), s, x, (0, oo))) \ == (1 - x)**(beta - 1)*Heaviside(1 - x) assert simp_pows(IMT(gamma(beta)*gamma(1 - beta - s)/gamma(1 - s), s, x, (-oo, None))) \ == (x - 1)**(beta - 1)*Heaviside(x - 1) assert simp_pows(IMT(gamma(s)*gamma(rho - s)/gamma(rho), s, x, (0, None))) \ == (1/(x + 1))**rho assert simp_pows(IMT(d**c*d**(s - 1)*sin(pi*c) *gamma(s)*gamma(s + c)*gamma(1 - s)*gamma(1 - s - c)/pi, s, x, (Max(-re(c), 0), Min(1 - re(c), 1)))) \ == (x**c - d**c)/(x - d) assert simplify(IMT(1/sqrt(pi)*(-c/2)*gamma(s)*gamma((1 - c)/2 - s) *gamma(-c/2 - s)/gamma(1 - c - s), s, x, (0, -re(c)/2))) == \ (1 + sqrt(x + 1))**c assert simplify(IMT(2**(a + 2*s)*b**(a + 2*s - 1)*gamma(s)*gamma(1 - a - 2*s) /gamma(1 - a - s), s, x, (0, (-re(a) + 1)/2))) == \ b**(a - 1)*(sqrt(1 + x/b**2) + 1)**(a - 1)*(b**2*sqrt(1 + x/b**2) + b**2 + x)/(b**2 + x) assert simplify(IMT(-2**(c + 2*s)*c*b**(c + 2*s)*gamma(s)*gamma(-c - 2*s) / gamma(-c - s + 1), s, x, (0, -re(c)/2))) == \ b**c*(sqrt(1 + x/b**2) + 1)**c # Section 8.4.5 assert IMT(24/s**5, s, x, (0, oo)) == log(x)**4*Heaviside(1 - x) assert expand(IMT(6/s**4, s, x, (-oo, 0)), force=True) == \ log(x)**3*Heaviside(x - 1) assert IMT(pi/(s*sin(pi*s)), s, x, (-1, 0)) == log(x + 1) assert IMT(pi/(s*sin(pi*s/2)), s, x, (-2, 0)) == log(x**2 + 1) assert IMT(pi/(s*sin(2*pi*s)), s, x, (Rational(-1, 2), 0)) == log(sqrt(x) + 1) assert IMT(pi/(s*sin(pi*s)), s, x, (0, 1)) == log(1 + 1/x) # TODO def mysimp(expr): from sympy import expand, logcombine, powsimp return expand( powsimp(logcombine(expr, force=True), force=True, deep=True), force=True).replace(exp_polar, exp) assert mysimp(mysimp(IMT(pi/(s*tan(pi*s)), s, x, (-1, 0)))) in [ log(1 - x)*Heaviside(1 - x) + log(x - 1)*Heaviside(x - 1), log(x)*Heaviside(x - 1) + log(1 - 1/x)*Heaviside(x - 1) + log(-x + 1)*Heaviside(-x + 1)] # test passing cot assert mysimp(IMT(pi*cot(pi*s)/s, s, x, (0, 1))) in [ log(1/x - 1)*Heaviside(1 - x) + log(1 - 1/x)*Heaviside(x - 1), -log(x)*Heaviside(-x + 1) + log(1 - 1/x)*Heaviside(x - 1) + log(-x + 1)*Heaviside(-x + 1), ] # 8.4.14 assert IMT(-gamma(s + S.Half)/(sqrt(pi)*s), s, x, (Rational(-1, 2), 0)) == \ erf(sqrt(x)) # 8.4.19 assert simplify(IMT(gamma(a/2 + s)/gamma(a/2 - s + 1), s, x, (-re(a)/2, Rational(3, 4)))) \ == besselj(a, 2*sqrt(x)) assert simplify(IMT(2**a*gamma(S.Half - 2*s)*gamma(s + (a + 1)/2) / (gamma(1 - s - a/2)*gamma(1 - 2*s + a)), s, x, (-(re(a) + 1)/2, Rational(1, 4)))) == \ sin(sqrt(x))*besselj(a, sqrt(x)) assert simplify(IMT(2**a*gamma(a/2 + s)*gamma(S.Half - 2*s) / (gamma(S.Half - s - a/2)*gamma(1 - 2*s + a)), s, x, (-re(a)/2, Rational(1, 4)))) == \ cos(sqrt(x))*besselj(a, sqrt(x)) # TODO this comes out as an amazing mess, but simplifies nicely assert simplify(IMT(gamma(a + s)*gamma(S.Half - s) / (sqrt(pi)*gamma(1 - s)*gamma(1 + a - s)), s, x, (-re(a), S.Half))) == \ besselj(a, sqrt(x))**2 assert simplify(IMT(gamma(s)*gamma(S.Half - s) / (sqrt(pi)*gamma(1 - s - a)*gamma(1 + a - s)), s, x, (0, S.Half))) == \ besselj(-a, sqrt(x))*besselj(a, sqrt(x)) assert simplify(IMT(4**s*gamma(-2*s + 1)*gamma(a/2 + b/2 + s) / (gamma(-a/2 + b/2 - s + 1)*gamma(a/2 - b/2 - s + 1) *gamma(a/2 + b/2 - s + 1)), s, x, (-(re(a) + re(b))/2, S.Half))) == \ besselj(a, sqrt(x))*besselj(b, sqrt(x)) # Section 8.4.20 # TODO this can be further simplified! assert simplify(IMT(-2**(2*s)*cos(pi*a/2 - pi*b/2 + pi*s)*gamma(-2*s + 1) * gamma(a/2 - b/2 + s)*gamma(a/2 + b/2 + s) / (pi*gamma(a/2 - b/2 - s + 1)*gamma(a/2 + b/2 - s + 1)), s, x, (Max(-re(a)/2 - re(b)/2, -re(a)/2 + re(b)/2), S.Half))) == \ besselj(a, sqrt(x))*-(besselj(-b, sqrt(x)) - besselj(b, sqrt(x))*cos(pi*b))/sin(pi*b) # TODO more # for coverage assert IMT(pi/cos(pi*s), s, x, (0, S.Half)) == sqrt(x)/(x + 1) @slow def test_laplace_transform(): from sympy import fresnels, fresnelc, DiracDelta LT = laplace_transform a, b, c, = symbols('a b c', positive=True) t = symbols('t') w = Symbol("w") f = Function("f") # Test unevaluated form assert laplace_transform(f(t), t, w) == LaplaceTransform(f(t), t, w) assert inverse_laplace_transform( f(w), w, t, plane=0) == InverseLaplaceTransform(f(w), w, t, 0) # test a bug spos = symbols('s', positive=True) assert LT(exp(t), t, spos)[:2] == (1/(spos - 1), 1) # basic tests from wikipedia assert LT((t - a)**b*exp(-c*(t - a))*Heaviside(t - a), t, s) == \ ((s + c)**(-b - 1)*exp(-a*s)*gamma(b + 1), -c, True) assert LT(t**a, t, s) == (s**(-a - 1)*gamma(a + 1), 0, True) assert LT(Heaviside(t), t, s) == (1/s, 0, True) assert LT(Heaviside(t - a), t, s) == (exp(-a*s)/s, 0, True) assert LT(1 - exp(-a*t), t, s) == (a/(s*(a + s)), 0, True) assert LT((exp(2*t) - 1)*exp(-b - t)*Heaviside(t)/2, t, s, noconds=True) \ == exp(-b)/(s**2 - 1) assert LT(exp(t), t, s)[:2] == (1/(s - 1), 1) assert LT(exp(2*t), t, s)[:2] == (1/(s - 2), 2) assert LT(exp(a*t), t, s)[:2] == (1/(s - a), a) assert LT(log(t/a), t, s) == ((log(a*s) + EulerGamma)/s/-1, 0, True) assert LT(erf(t), t, s) == (erfc(s/2)*exp(s**2/4)/s, 0, True) assert LT(sin(a*t), t, s) == (a/(a**2 + s**2), 0, True) assert LT(cos(a*t), t, s) == (s/(a**2 + s**2), 0, True) # TODO would be nice to have these come out better assert LT(exp(-a*t)*sin(b*t), t, s) == (b/(b**2 + (a + s)**2), -a, True) assert LT(exp(-a*t)*cos(b*t), t, s) == \ ((a + s)/(b**2 + (a + s)**2), -a, True) assert LT(besselj(0, t), t, s) == (1/sqrt(1 + s**2), 0, True) assert LT(besselj(1, t), t, s) == (1 - 1/sqrt(1 + 1/s**2), 0, True) # TODO general order works, but is a *mess* # TODO besseli also works, but is an even greater mess # test a bug in conditions processing # TODO the auxiliary condition should be recognised/simplified assert LT(exp(t)*cos(t), t, s)[:-1] in [ ((s - 1)/(s**2 - 2*s + 2), -oo), ((s - 1)/((s - 1)**2 + 1), -oo), ] # DiracDelta function: standard cases assert LT(DiracDelta(t), t, s) == (1, -oo, True) assert LT(DiracDelta(a*t), t, s) == (1/a, -oo, True) assert LT(DiracDelta(t/42), t, s) == (42, -oo, True) assert LT(DiracDelta(t+42), t, s) == (0, -oo, True) assert LT(DiracDelta(t)+DiracDelta(t-42), t, s) == \ (1 + exp(-42*s), -oo, True) assert LT(DiracDelta(t)-a*exp(-a*t), t, s) == (-a/(a + s) + 1, 0, True) assert LT(exp(-t)*(DiracDelta(t)+DiracDelta(t-42)), t, s) == \ (exp(-42*s - 42) + 1, -oo, True) # Collection of cases that cannot be fully evaluated and/or would catch # some common implementation errors assert LT(DiracDelta(t**2), t, s) == LaplaceTransform(DiracDelta(t**2), t, s) assert LT(DiracDelta(t**2 - 1), t, s) == (exp(-s)/2, -oo, True) assert LT(DiracDelta(t*(1 - t)), t, s) == \ LaplaceTransform(DiracDelta(-t**2 + t), t, s) assert LT((DiracDelta(t) + 1)*(DiracDelta(t - 1) + 1), t, s) == \ (LaplaceTransform(DiracDelta(t)*DiracDelta(t - 1), t, s) + \ 1 + exp(-s) + 1/s, 0, True) assert LT(DiracDelta(2*t - 2*exp(a)), t, s) == \ (exp(-s*exp(a))/2, -oo, True) # Fresnel functions assert laplace_transform(fresnels(t), t, s) == \ ((-sin(s**2/(2*pi))*fresnels(s/pi) + sin(s**2/(2*pi))/2 - cos(s**2/(2*pi))*fresnelc(s/pi) + cos(s**2/(2*pi))/2)/s, 0, True) assert laplace_transform(fresnelc(t), t, s) == ( ((2*sin(s**2/(2*pi))*fresnelc(s/pi) - 2*cos(s**2/(2*pi))*fresnels(s/pi) + sqrt(2)*cos(s**2/(2*pi) + pi/4))/(2*s), 0, True)) # What is this testing: Ne(1/s, 1) & (0 < cos(Abs(periodic_argument(s, oo)))*Abs(s) - 1) Mt = Matrix([[exp(t), t*exp(-t)], [t*exp(-t), exp(t)]]) Ms = Matrix([[ 1/(s - 1), (s + 1)**(-2)], [(s + 1)**(-2), 1/(s - 1)]]) # The default behaviour for Laplace tranform of a Matrix returns a Matrix # of Tuples and is deprecated: with warns_deprecated_sympy(): Ms_conds = Matrix([[(1/(s - 1), 1, s > 1), ((s + 1)**(-2), 0, True)], [((s + 1)**(-2), 0, True), (1/(s - 1), 1, s > 1)]]) with warns_deprecated_sympy(): assert LT(Mt, t, s) == Ms_conds # The new behavior is to return a tuple of a Matrix and the convergence # conditions for the matrix as a whole: assert LT(Mt, t, s, legacy_matrix=False) == (Ms, 1, s > 1) # With noconds=True the transformed matrix is returned without conditions # either way: assert LT(Mt, t, s, noconds=True) == Ms assert LT(Mt, t, s, legacy_matrix=False, noconds=True) == Ms def test_issue_8368_7173(): LT = laplace_transform # hyperbolic assert LT(sinh(x), x, s) == (1/(s**2 - 1), 1, s > 1) assert LT(cosh(x), x, s) == (s/(s**2 - 1), 1, s > 1) assert LT(sinh(x + 3), x, s) == ( (-s + (s + 1)*exp(6) + 1)*exp(-3)/(s - 1)/(s + 1)/2, 1, s > 1) assert LT(sinh(x)*cosh(x), x, s) == ( 1/(s**2 - 4), 2, s > 2) # trig (make sure they are not being rewritten in terms of exp) assert LT(cos(x + 3), x, s) == ((s*cos(3) - sin(3))/(s**2 + 1), 0, True) def test_inverse_laplace_transform(): from sympy import sinh, cosh, besselj, besseli, simplify, factor_terms,\ DiracDelta ILT = inverse_laplace_transform a, b, c, = symbols('a b c', positive=True) t = symbols('t') def simp_hyp(expr): return factor_terms(expand_mul(expr)).rewrite(sin) assert ILT(1, s, t) == DiracDelta(t) assert ILT(1/s, s, t) == Heaviside(t) assert ILT(a/(a + s), s, t) == a*exp(-a*t)*Heaviside(t) assert ILT(s/(a + s), s, t) == -a*exp(-a*t)*Heaviside(t) + DiracDelta(t) assert ILT((a + s)**(-2), s, t) == t*exp(-a*t)*Heaviside(t) assert ILT((a + s)**(-5), s, t) == t**4*exp(-a*t)*Heaviside(t)/24 assert ILT(a/(a**2 + s**2), s, t) == sin(a*t)*Heaviside(t) assert ILT(s/(s**2 + a**2), s, t) == cos(a*t)*Heaviside(t) assert ILT(b/(b**2 + (a + s)**2), s, t) == exp(-a*t)*sin(b*t)*Heaviside(t) assert ILT(b*s/(b**2 + (a + s)**2), s, t) +\ (a*sin(b*t) - b*cos(b*t))*exp(-a*t)*Heaviside(t) == 0 assert ILT(exp(-a*s)/s, s, t) == Heaviside(-a + t) assert ILT(exp(-a*s)/(b + s), s, t) == exp(b*(a - t))*Heaviside(-a + t) assert ILT((b + s)/(a**2 + (b + s)**2), s, t) == \ exp(-b*t)*cos(a*t)*Heaviside(t) assert ILT(exp(-a*s)/s**b, s, t) == \ (-a + t)**(b - 1)*Heaviside(-a + t)/gamma(b) assert ILT(exp(-a*s)/sqrt(s**2 + 1), s, t) == \ Heaviside(-a + t)*besselj(0, a - t) assert ILT(1/(s*sqrt(s + 1)), s, t) == Heaviside(t)*erf(sqrt(t)) assert ILT(1/(s**2*(s**2 + 1)), s, t) == (t - sin(t))*Heaviside(t) assert ILT(s**2/(s**2 + 1), s, t) == -sin(t)*Heaviside(t) + DiracDelta(t) assert ILT(1 - 1/(s**2 + 1), s, t) == -sin(t)*Heaviside(t) + DiracDelta(t) assert ILT(1/s**2, s, t) == t*Heaviside(t) assert ILT(1/s**5, s, t) == t**4*Heaviside(t)/24 assert simp_hyp(ILT(a/(s**2 - a**2), s, t)) == sinh(a*t)*Heaviside(t) assert simp_hyp(ILT(s/(s**2 - a**2), s, t)) == cosh(a*t)*Heaviside(t) # TODO sinh/cosh shifted come out a mess. also delayed trig is a mess # TODO should this simplify further? assert ILT(exp(-a*s)/s**b, s, t) == \ (t - a)**(b - 1)*Heaviside(t - a)/gamma(b) assert ILT(exp(-a*s)/sqrt(1 + s**2), s, t) == \ Heaviside(t - a)*besselj(0, a - t) # note: besselj(0, x) is even # XXX ILT turns these branch factor into trig functions ... assert simplify(ILT(a**b*(s + sqrt(s**2 - a**2))**(-b)/sqrt(s**2 - a**2), s, t).rewrite(exp)) == \ Heaviside(t)*besseli(b, a*t) assert ILT(a**b*(s + sqrt(s**2 + a**2))**(-b)/sqrt(s**2 + a**2), s, t).rewrite(exp) == \ Heaviside(t)*besselj(b, a*t) assert ILT(1/(s*sqrt(s + 1)), s, t) == Heaviside(t)*erf(sqrt(t)) # TODO can we make erf(t) work? assert ILT(1/(s**2*(s**2 + 1)),s,t) == (t - sin(t))*Heaviside(t) assert ILT( (s * eye(2) - Matrix([[1, 0], [0, 2]])).inv(), s, t) ==\ Matrix([[exp(t)*Heaviside(t), 0], [0, exp(2*t)*Heaviside(t)]]) def test_inverse_laplace_transform_delta(): from sympy import DiracDelta ILT = inverse_laplace_transform t = symbols('t') assert ILT(2, s, t) == 2*DiracDelta(t) assert ILT(2*exp(3*s) - 5*exp(-7*s), s, t) == \ 2*DiracDelta(t + 3) - 5*DiracDelta(t - 7) a = cos(sin(7)/2) assert ILT(a*exp(-3*s), s, t) == a*DiracDelta(t - 3) assert ILT(exp(2*s), s, t) == DiracDelta(t + 2) r = Symbol('r', real=True) assert ILT(exp(r*s), s, t) == DiracDelta(t + r) def test_inverse_laplace_transform_delta_cond(): from sympy import DiracDelta, Eq, im, Heaviside ILT = inverse_laplace_transform t = symbols('t') r = Symbol('r', real=True) assert ILT(exp(r*s), s, t, noconds=False) == (DiracDelta(t + r), True) z = Symbol('z') assert ILT(exp(z*s), s, t, noconds=False) == \ (DiracDelta(t + z), Eq(im(z), 0)) # inversion does not exist: verify it doesn't evaluate to DiracDelta for z in (Symbol('z', extended_real=False), Symbol('z', imaginary=True, zero=False)): f = ILT(exp(z*s), s, t, noconds=False) f = f[0] if isinstance(f, tuple) else f assert f.func != DiracDelta # issue 15043 assert ILT(1/s + exp(r*s)/s, s, t, noconds=False) == ( Heaviside(t) + Heaviside(r + t), True) def test_fourier_transform(): from sympy import simplify, expand, expand_complex, factor, expand_trig FT = fourier_transform IFT = inverse_fourier_transform def simp(x): return simplify(expand_trig(expand_complex(expand(x)))) def sinc(x): return sin(pi*x)/(pi*x) k = symbols('k', real=True) f = Function("f") # TODO for this to work with real a, need to expand abs(a*x) to abs(a)*abs(x) a = symbols('a', positive=True) b = symbols('b', positive=True) posk = symbols('posk', positive=True) # Test unevaluated form assert fourier_transform(f(x), x, k) == FourierTransform(f(x), x, k) assert inverse_fourier_transform( f(k), k, x) == InverseFourierTransform(f(k), k, x) # basic examples from wikipedia assert simp(FT(Heaviside(1 - abs(2*a*x)), x, k)) == sinc(k/a)/a # TODO IFT is a *mess* assert simp(FT(Heaviside(1 - abs(a*x))*(1 - abs(a*x)), x, k)) == sinc(k/a)**2/a # TODO IFT assert factor(FT(exp(-a*x)*Heaviside(x), x, k), extension=I) == \ 1/(a + 2*pi*I*k) # NOTE: the ift comes out in pieces assert IFT(1/(a + 2*pi*I*x), x, posk, noconds=False) == (exp(-a*posk), True) assert IFT(1/(a + 2*pi*I*x), x, -posk, noconds=False) == (0, True) assert IFT(1/(a + 2*pi*I*x), x, symbols('k', negative=True), noconds=False) == (0, True) # TODO IFT without factoring comes out as meijer g assert factor(FT(x*exp(-a*x)*Heaviside(x), x, k), extension=I) == \ 1/(a + 2*pi*I*k)**2 assert FT(exp(-a*x)*sin(b*x)*Heaviside(x), x, k) == \ b/(b**2 + (a + 2*I*pi*k)**2) assert FT(exp(-a*x**2), x, k) == sqrt(pi)*exp(-pi**2*k**2/a)/sqrt(a) assert IFT(sqrt(pi/a)*exp(-(pi*k)**2/a), k, x) == exp(-a*x**2) assert FT(exp(-a*abs(x)), x, k) == 2*a/(a**2 + 4*pi**2*k**2) # TODO IFT (comes out as meijer G) # TODO besselj(n, x), n an integer > 0 actually can be done... # TODO are there other common transforms (no distributions!)? def test_sine_transform(): from sympy import EulerGamma t = symbols("t") w = symbols("w") a = symbols("a") f = Function("f") # Test unevaluated form assert sine_transform(f(t), t, w) == SineTransform(f(t), t, w) assert inverse_sine_transform( f(w), w, t) == InverseSineTransform(f(w), w, t) assert sine_transform(1/sqrt(t), t, w) == 1/sqrt(w) assert inverse_sine_transform(1/sqrt(w), w, t) == 1/sqrt(t) assert sine_transform((1/sqrt(t))**3, t, w) == 2*sqrt(w) assert sine_transform(t**(-a), t, w) == 2**( -a + S.Half)*w**(a - 1)*gamma(-a/2 + 1)/gamma((a + 1)/2) assert inverse_sine_transform(2**(-a + S( 1)/2)*w**(a - 1)*gamma(-a/2 + 1)/gamma(a/2 + S.Half), w, t) == t**(-a) assert sine_transform( exp(-a*t), t, w) == sqrt(2)*w/(sqrt(pi)*(a**2 + w**2)) assert inverse_sine_transform( sqrt(2)*w/(sqrt(pi)*(a**2 + w**2)), w, t) == exp(-a*t) assert sine_transform( log(t)/t, t, w) == -sqrt(2)*sqrt(pi)*(log(w**2) + 2*EulerGamma)/4 assert sine_transform( t*exp(-a*t**2), t, w) == sqrt(2)*w*exp(-w**2/(4*a))/(4*a**Rational(3, 2)) assert inverse_sine_transform( sqrt(2)*w*exp(-w**2/(4*a))/(4*a**Rational(3, 2)), w, t) == t*exp(-a*t**2) def test_cosine_transform(): from sympy import Si, Ci t = symbols("t") w = symbols("w") a = symbols("a") f = Function("f") # Test unevaluated form assert cosine_transform(f(t), t, w) == CosineTransform(f(t), t, w) assert inverse_cosine_transform( f(w), w, t) == InverseCosineTransform(f(w), w, t) assert cosine_transform(1/sqrt(t), t, w) == 1/sqrt(w) assert inverse_cosine_transform(1/sqrt(w), w, t) == 1/sqrt(t) assert cosine_transform(1/( a**2 + t**2), t, w) == sqrt(2)*sqrt(pi)*exp(-a*w)/(2*a) assert cosine_transform(t**( -a), t, w) == 2**(-a + S.Half)*w**(a - 1)*gamma((-a + 1)/2)/gamma(a/2) assert inverse_cosine_transform(2**(-a + S( 1)/2)*w**(a - 1)*gamma(-a/2 + S.Half)/gamma(a/2), w, t) == t**(-a) assert cosine_transform( exp(-a*t), t, w) == sqrt(2)*a/(sqrt(pi)*(a**2 + w**2)) assert inverse_cosine_transform( sqrt(2)*a/(sqrt(pi)*(a**2 + w**2)), w, t) == exp(-a*t) assert cosine_transform(exp(-a*sqrt(t))*cos(a*sqrt( t)), t, w) == a*exp(-a**2/(2*w))/(2*w**Rational(3, 2)) assert cosine_transform(1/(a + t), t, w) == sqrt(2)*( (-2*Si(a*w) + pi)*sin(a*w)/2 - cos(a*w)*Ci(a*w))/sqrt(pi) assert inverse_cosine_transform(sqrt(2)*meijerg(((S.Half, 0), ()), ( (S.Half, 0, 0), (S.Half,)), a**2*w**2/4)/(2*pi), w, t) == 1/(a + t) assert cosine_transform(1/sqrt(a**2 + t**2), t, w) == sqrt(2)*meijerg( ((S.Half,), ()), ((0, 0), (S.Half,)), a**2*w**2/4)/(2*sqrt(pi)) assert inverse_cosine_transform(sqrt(2)*meijerg(((S.Half,), ()), ((0, 0), (S.Half,)), a**2*w**2/4)/(2*sqrt(pi)), w, t) == 1/(t*sqrt(a**2/t**2 + 1)) def test_hankel_transform(): from sympy import gamma, sqrt, exp r = Symbol("r") k = Symbol("k") nu = Symbol("nu") m = Symbol("m") a = symbols("a") assert hankel_transform(1/r, r, k, 0) == 1/k assert inverse_hankel_transform(1/k, k, r, 0) == 1/r assert hankel_transform( 1/r**m, r, k, 0) == 2**(-m + 1)*k**(m - 2)*gamma(-m/2 + 1)/gamma(m/2) assert inverse_hankel_transform( 2**(-m + 1)*k**(m - 2)*gamma(-m/2 + 1)/gamma(m/2), k, r, 0) == r**(-m) assert hankel_transform(1/r**m, r, k, nu) == ( 2*2**(-m)*k**(m - 2)*gamma(-m/2 + nu/2 + 1)/gamma(m/2 + nu/2)) assert inverse_hankel_transform(2**(-m + 1)*k**( m - 2)*gamma(-m/2 + nu/2 + 1)/gamma(m/2 + nu/2), k, r, nu) == r**(-m) assert hankel_transform(r**nu*exp(-a*r), r, k, nu) == \ 2**(nu + 1)*a*k**(-nu - 3)*(a**2/k**2 + 1)**(-nu - S( 3)/2)*gamma(nu + Rational(3, 2))/sqrt(pi) assert inverse_hankel_transform( 2**(nu + 1)*a*k**(-nu - 3)*(a**2/k**2 + 1)**(-nu - Rational(3, 2))*gamma( nu + Rational(3, 2))/sqrt(pi), k, r, nu) == r**nu*exp(-a*r) def test_issue_7181(): assert mellin_transform(1/(1 - x), x, s) != None def test_issue_8882(): # This is the original test. # from sympy import diff, Integral, integrate # r = Symbol('r') # psi = 1/r*sin(r)*exp(-(a0*r)) # h = -1/2*diff(psi, r, r) - 1/r*psi # f = 4*pi*psi*h*r**2 # assert integrate(f, (r, -oo, 3), meijerg=True).has(Integral) == True # To save time, only the critical part is included. F = -a**(-s + 1)*(4 + 1/a**2)**(-s/2)*sqrt(1/a**2)*exp(-s*I*pi)* \ sin(s*atan(sqrt(1/a**2)/2))*gamma(s) raises(IntegralTransformError, lambda: inverse_mellin_transform(F, s, x, (-1, oo), **{'as_meijerg': True, 'needeval': True})) def test_issue_7173(): from sympy import cse x0, x1, x2, x3 = symbols('x:4') ans = laplace_transform(sinh(a*x)*cosh(a*x), x, s) r, e = cse(ans) assert r == [ (x0, arg(a)), (x1, Abs(x0)), (x2, pi/2), (x3, Abs(x0 + pi))] assert e == [ a/(-4*a**2 + s**2), 0, ((x1 <= x2) | (x1 < x2)) & ((x3 <= x2) | (x3 < x2))] def test_issue_8514(): from sympy import simplify a, b, c, = symbols('a b c', positive=True) t = symbols('t', positive=True) ft = simplify(inverse_laplace_transform(1/(a*s**2+b*s+c),s, t)) assert ft == (I*exp(t*cos(atan2(0, -4*a*c + b**2)/2)*sqrt(Abs(4*a*c - b**2))/a)*sin(t*sin(atan2(0, -4*a*c + b**2)/2)*sqrt(Abs( 4*a*c - b**2))/(2*a)) + exp(t*cos(atan2(0, -4*a*c + b**2) /2)*sqrt(Abs(4*a*c - b**2))/a)*cos(t*sin(atan2(0, -4*a*c + b**2)/2)*sqrt(Abs(4*a*c - b**2))/(2*a)) + I*sin(t*sin( atan2(0, -4*a*c + b**2)/2)*sqrt(Abs(4*a*c - b**2))/(2*a)) - cos(t*sin(atan2(0, -4*a*c + b**2)/2)*sqrt(Abs(4*a*c - b**2))/(2*a)))*exp(-t*(b + cos(atan2(0, -4*a*c + b**2)/2) *sqrt(Abs(4*a*c - b**2)))/(2*a))/sqrt(-4*a*c + b**2) def test_issue_12591(): x, y = symbols("x y", real=True) assert fourier_transform(exp(x), x, y) == FourierTransform(exp(x), x, y) def test_issue_14692(): b = Symbol('b', negative=True) assert laplace_transform(1/(I*x - b), x, s) == \ (-I*exp(I*b*s)*expint(1, b*s*exp_polar(I*pi/2)), 0, True)
1a1099a2155d0dd458e83054a7fe6d0d2aa07a84ff8bccfdff5d149c02353bc6
"""Most of these tests come from the examples in Bronstein's book.""" from sympy.integrals.risch import DifferentialExtension, derivation from sympy.integrals.prde import (prde_normal_denom, prde_special_denom, prde_linear_constraints, constant_system, prde_spde, prde_no_cancel_b_large, prde_no_cancel_b_small, limited_integrate_reduce, limited_integrate, is_deriv_k, is_log_deriv_k_t_radical, parametric_log_deriv_heu, is_log_deriv_k_t_radical_in_field, param_poly_rischDE, param_rischDE, prde_cancel_liouvillian) from sympy.polys.polymatrix import PolyMatrix as Matrix from sympy import Poly, S, symbols, Rational, QQ from sympy.abc import x, t, n t0, t1, t2, t3, k = symbols('t:4 k') def test_prde_normal_denom(): DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(1 + t**2, t)]}) fa = Poly(1, t) fd = Poly(x, t) G = [(Poly(t, t), Poly(1 + t**2, t)), (Poly(1, t), Poly(x + x*t**2, t))] assert prde_normal_denom(fa, fd, G, DE) == \ (Poly(x, t, domain='ZZ(x)'), (Poly(1, t, domain='ZZ(x)'), Poly(1, t, domain='ZZ(x)')), [(Poly(x*t, t, domain='ZZ(x)'), Poly(t**2 + 1, t, domain='ZZ(x)')), (Poly(1, t, domain='ZZ(x)'), Poly(t**2 + 1, t, domain='ZZ(x)'))], Poly(1, t, domain='ZZ(x)')) G = [(Poly(t, t), Poly(t**2 + 2*t + 1, t)), (Poly(x*t, t), Poly(t**2 + 2*t + 1, t)), (Poly(x*t**2, t), Poly(t**2 + 2*t + 1, t))] DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(t, t)]}) assert prde_normal_denom(Poly(x, t), Poly(1, t), G, DE) == \ (Poly(t + 1, t), (Poly((-1 + x)*t + x, t), Poly(1, t, domain='ZZ[x]')), [(Poly(t, t), Poly(1, t)), (Poly(x*t, t), Poly(1, t, domain='ZZ[x]')), (Poly(x*t**2, t), Poly(1, t, domain='ZZ[x]'))], Poly(t + 1, t)) def test_prde_special_denom(): a = Poly(t + 1, t) ba = Poly(t**2, t) bd = Poly(1, t) G = [(Poly(t, t), Poly(1, t)), (Poly(t**2, t), Poly(1, t)), (Poly(t**3, t), Poly(1, t))] DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(t, t)]}) assert prde_special_denom(a, ba, bd, G, DE) == \ (Poly(t + 1, t), Poly(t**2, t), [(Poly(t, t), Poly(1, t)), (Poly(t**2, t), Poly(1, t)), (Poly(t**3, t), Poly(1, t))], Poly(1, t)) G = [(Poly(t, t), Poly(1, t)), (Poly(1, t), Poly(t, t))] assert prde_special_denom(Poly(1, t), Poly(t**2, t), Poly(1, t), G, DE) == \ (Poly(1, t), Poly(t**2 - 1, t), [(Poly(t**2, t), Poly(1, t)), (Poly(1, t), Poly(1, t))], Poly(t, t)) DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(-2*x*t0, t0)]}) DE.decrement_level() G = [(Poly(t, t), Poly(t**2, t)), (Poly(2*t, t), Poly(t, t))] assert prde_special_denom(Poly(5*x*t + 1, t), Poly(t**2 + 2*x**3*t, t), Poly(t**3 + 2, t), G, DE) == \ (Poly(5*x*t + 1, t), Poly(0, t, domain='ZZ[x]'), [(Poly(t, t), Poly(t**2, t)), (Poly(2*t, t), Poly(t, t))], Poly(1, x)) DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly((t**2 + 1)*2*x, t)]}) G = [(Poly(t + x, t), Poly(t*x, t)), (Poly(2*t, t), Poly(x**2, x))] assert prde_special_denom(Poly(5*x*t + 1, t), Poly(t**2 + 2*x**3*t, t), Poly(t**3, t), G, DE) == \ (Poly(5*x*t + 1, t), Poly(0, t, domain='ZZ[x]'), [(Poly(t + x, t), Poly(x*t, t)), (Poly(2*t, t, x), Poly(x**2, t, x))], Poly(1, t)) assert prde_special_denom(Poly(t + 1, t), Poly(t**2, t), Poly(t**3, t), G, DE) == \ (Poly(t + 1, t), Poly(0, t, domain='ZZ[x]'), [(Poly(t + x, t), Poly(x*t, t)), (Poly(2*t, t, x), Poly(x**2, t, x))], Poly(1, t)) def test_prde_linear_constraints(): DE = DifferentialExtension(extension={'D': [Poly(1, x)]}) G = [(Poly(2*x**3 + 3*x + 1, x), Poly(x**2 - 1, x)), (Poly(1, x), Poly(x - 1, x)), (Poly(1, x), Poly(x + 1, x))] assert prde_linear_constraints(Poly(1, x), Poly(0, x), G, DE) == \ ((Poly(2*x, x, domain='QQ'), Poly(0, x, domain='QQ'), Poly(0, x, domain='QQ')), Matrix([[1, 1, -1], [5, 1, 1]], x)) G = [(Poly(t, t), Poly(1, t)), (Poly(t**2, t), Poly(1, t)), (Poly(t**3, t), Poly(1, t))] DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(t, t)]}) assert prde_linear_constraints(Poly(t + 1, t), Poly(t**2, t), G, DE) == \ ((Poly(t, t, domain='QQ'), Poly(t**2, t, domain='QQ'), Poly(t**3, t, domain='QQ')), Matrix(0, 3, [], t)) G = [(Poly(2*x, t), Poly(t, t)), (Poly(-x, t), Poly(t, t))] DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(1/x, t)]}) assert prde_linear_constraints(Poly(1, t), Poly(0, t), G, DE) == \ ((Poly(0, t, domain='QQ[x]'), Poly(0, t, domain='QQ[x]')), Matrix([[2*x, -x]], t)) def test_constant_system(): A = Matrix([[-(x + 3)/(x - 1), (x + 1)/(x - 1), 1], [-x - 3, x + 1, x - 1], [2*(x + 3)/(x - 1), 0, 0]], t) u = Matrix([[(x + 1)/(x - 1)], [x + 1], [0]], t) DE = DifferentialExtension(extension={'D': [Poly(1, x)]}) R = QQ.frac_field(x)[t] assert constant_system(A, u, DE) == \ (Matrix([[1, 0, 0], [0, 1, 0], [0, 0, 0], [0, 0, 1]], ring=R), Matrix([0, 1, 0, 0], ring=R)) def test_prde_spde(): D = [Poly(x, t), Poly(-x*t, t)] DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(1/x, t)]}) # TODO: when bound_degree() can handle this, test degree bound from that too assert prde_spde(Poly(t, t), Poly(-1/x, t), D, n, DE) == \ (Poly(t, t), Poly(0, t, domain='ZZ(x)'), [Poly(2*x, t, domain='ZZ(x)'), Poly(-x, t, domain='ZZ(x)')], [Poly(-x**2, t, domain='ZZ(x)'), Poly(0, t, domain='ZZ(x)')], n - 1) def test_prde_no_cancel(): # b large DE = DifferentialExtension(extension={'D': [Poly(1, x)]}) assert prde_no_cancel_b_large(Poly(1, x), [Poly(x**2, x), Poly(1, x)], 2, DE) == \ ([Poly(x**2 - 2*x + 2, x), Poly(1, x)], Matrix([[1, 0, -1, 0], [0, 1, 0, -1]], x)) assert prde_no_cancel_b_large(Poly(1, x), [Poly(x**3, x), Poly(1, x)], 3, DE) == \ ([Poly(x**3 - 3*x**2 + 6*x - 6, x), Poly(1, x)], Matrix([[1, 0, -1, 0], [0, 1, 0, -1]], x)) assert prde_no_cancel_b_large(Poly(x, x), [Poly(x**2, x), Poly(1, x)], 1, DE) == \ ([Poly(x, x, domain='ZZ'), Poly(0, x, domain='ZZ')], Matrix([[1, -1, 0, 0], [1, 0, -1, 0], [0, 1, 0, -1]], x)) # b small # XXX: Is there a better example of a monomial with D.degree() > 2? DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(t**3 + 1, t)]}) # My original q was t**4 + t + 1, but this solution implies q == t**4 # (c1 = 4), with some of the ci for the original q equal to 0. G = [Poly(t**6, t), Poly(x*t**5, t), Poly(t**3, t), Poly(x*t**2, t), Poly(1 + x, t)] R = QQ.frac_field(x)[t] assert prde_no_cancel_b_small(Poly(x*t, t), G, 4, DE) == \ ([Poly(t**4/4 - x/12*t**3 + x**2/24*t**2 + (Rational(-11, 12) - x**3/24)*t + x/24, t), Poly(x/3*t**3 - x**2/6*t**2 + (Rational(-1, 3) + x**3/6)*t - x/6, t), Poly(t, t), Poly(0, t), Poly(0, t)], Matrix([[1, 0, -1, 0, 0, 0, 0, 0, 0, 0], [0, 1, Rational(-1, 4), 0, 0, 0, 0, 0, 0, 0], [0, 0, 0, 0, 0, 0, 0, 0, 0, 0], [0, 0, 0, 1, 0, 0, 0, 0, 0, 0], [0, 0, 0, 0, 1, 0, 0, 0, 0, 0], [1, 0, 0, 0, 0, -1, 0, 0, 0, 0], [0, 1, 0, 0, 0, 0, -1, 0, 0, 0], [0, 0, 1, 0, 0, 0, 0, -1, 0, 0], [0, 0, 0, 1, 0, 0, 0, 0, -1, 0], [0, 0, 0, 0, 1, 0, 0, 0, 0, -1]], ring=R)) # TODO: Add test for deg(b) <= 0 with b small DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(1 + t**2, t)]}) b = Poly(-1/x**2, t, field=True) # deg(b) == 0 q = [Poly(x**i*t**j, t, field=True) for i in range(2) for j in range(3)] h, A = prde_no_cancel_b_small(b, q, 3, DE) V = A.nullspace() R = QQ.frac_field(x)[t] assert len(V) == 1 assert V[0] == Matrix([Rational(-1, 2), 0, 0, 1, 0, 0]*3, ring=R) assert (Matrix([h])*V[0][6:, :])[0] == Poly(x**2/2, t, domain='QQ(x)') assert (Matrix([q])*V[0][:6, :])[0] == Poly(x - S.Half, t, domain='QQ(x)') def test_prde_cancel_liouvillian(): ### 1. case == 'primitive' # used when integrating f = log(x) - log(x - 1) # Not taken from 'the' book DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(1/x, t)]}) p0 = Poly(0, t, field=True) h, A = prde_cancel_liouvillian(Poly(-1/(x - 1), t), [Poly(-x + 1, t), Poly(1, t)], 1, DE) V = A.nullspace() h == [p0, p0, Poly((x - 1)*t, t), p0, p0, p0, p0, p0, p0, p0, Poly(x - 1, t), Poly(-x**2 + x, t), p0, p0, p0, p0] assert A.rank() == 16 assert (Matrix([h])*V[0][:16, :]) == Matrix([[Poly(0, t, domain='QQ(x)')]]) ### 2. case == 'exp' # used when integrating log(x/exp(x) + 1) # Not taken from book DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(-t, t)]}) assert prde_cancel_liouvillian(Poly(0, t, domain='QQ[x]'), [Poly(1, t, domain='QQ(x)')], 0, DE) == \ ([Poly(1, t, domain='QQ'), Poly(x, t, domain='ZZ(x)')], Matrix([[-1, 0, 1]], DE.t)) def test_param_poly_rischDE(): DE = DifferentialExtension(extension={'D': [Poly(1, x)]}) a = Poly(x**2 - x, x, field=True) b = Poly(1, x, field=True) q = [Poly(x, x, field=True), Poly(x**2, x, field=True)] h, A = param_poly_rischDE(a, b, q, 3, DE) assert A.nullspace() == [Matrix([0, 1, 1, 1], DE.t)] # c1, c2, d1, d2 # Solution of a*Dp + b*p = c1*q1 + c2*q2 = q2 = x**2 # is d1*h1 + d2*h2 = h1 + h2 = x. assert h[0] + h[1] == Poly(x, x, domain='QQ') # a*Dp + b*p = q1 = x has no solution. a = Poly(x**2 - x, x, field=True) b = Poly(x**2 - 5*x + 3, x, field=True) q = [Poly(1, x, field=True), Poly(x, x, field=True), Poly(x**2, x, field=True)] h, A = param_poly_rischDE(a, b, q, 3, DE) assert A.nullspace() == [Matrix([3, -5, 1, -5, 1, 1], DE.t)] p = -Poly(5, DE.t)*h[0] + h[1] + h[2] # Poly(1, x) assert a*derivation(p, DE) + b*p == Poly(x**2 - 5*x + 3, x, domain='QQ') def test_param_rischDE(): DE = DifferentialExtension(extension={'D': [Poly(1, x)]}) p1, px = Poly(1, x, field=True), Poly(x, x, field=True) G = [(p1, px), (p1, p1), (px, p1)] # [1/x, 1, x] h, A = param_rischDE(-p1, Poly(x**2, x, field=True), G, DE) assert len(h) == 3 p = [hi[0].as_expr()/hi[1].as_expr() for hi in h] V = A.nullspace() assert len(V) == 2 assert V[0] == Matrix([-1, 1, 0, -1, 1, 0], DE.t) y = -p[0] + p[1] + 0*p[2] # x assert y.diff(x) - y/x**2 == 1 - 1/x # Dy + f*y == -G0 + G1 + 0*G2 # the below test computation takes place while computing the integral # of 'f = log(log(x + exp(x)))' DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(t, t)]}) G = [(Poly(t + x, t, domain='ZZ(x)'), Poly(1, t, domain='QQ')), (Poly(0, t, domain='QQ'), Poly(1, t, domain='QQ'))] h, A = param_rischDE(Poly(-t - 1, t, field=True), Poly(t + x, t, field=True), G, DE) assert len(h) == 5 p = [hi[0].as_expr()/hi[1].as_expr() for hi in h] V = A.nullspace() assert len(V) == 3 assert V[0] == Matrix([0, 0, 0, 0, 1, 0, 0], DE.t) y = 0*p[0] + 0*p[1] + 1*p[2] + 0*p[3] + 0*p[4] assert y.diff(t) - y/(t + x) == 0 # Dy + f*y = 0*G0 + 0*G1 def test_limited_integrate_reduce(): DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(1/x, t)]}) assert limited_integrate_reduce(Poly(x, t), Poly(t**2, t), [(Poly(x, t), Poly(t, t))], DE) == \ (Poly(t, t), Poly(-1/x, t), Poly(t, t), 1, (Poly(x, t), Poly(1, t, domain='ZZ[x]')), [(Poly(-x*t, t), Poly(1, t, domain='ZZ[x]'))]) def test_limited_integrate(): DE = DifferentialExtension(extension={'D': [Poly(1, x)]}) G = [(Poly(x, x), Poly(x + 1, x))] assert limited_integrate(Poly(-(1 + x + 5*x**2 - 3*x**3), x), Poly(1 - x - x**2 + x**3, x), G, DE) == \ ((Poly(x**2 - x + 2, x), Poly(x - 1, x, domain='QQ')), [2]) G = [(Poly(1, x), Poly(x, x))] assert limited_integrate(Poly(5*x**2, x), Poly(3, x), G, DE) == \ ((Poly(5*x**3/9, x), Poly(1, x, domain='QQ')), [0]) def test_is_log_deriv_k_t_radical(): DE = DifferentialExtension(extension={'D': [Poly(1, x)], 'exts': [None], 'extargs': [None]}) assert is_log_deriv_k_t_radical(Poly(2*x, x), Poly(1, x), DE) is None DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(2*t1, t1), Poly(1/x, t2)], 'exts': [None, 'exp', 'log'], 'extargs': [None, 2*x, x]}) assert is_log_deriv_k_t_radical(Poly(x + t2/2, t2), Poly(1, t2), DE) == \ ([(t1, 1), (x, 1)], t1*x, 2, 0) # TODO: Add more tests DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(t0, t0), Poly(1/x, t)], 'exts': [None, 'exp', 'log'], 'extargs': [None, x, x]}) assert is_log_deriv_k_t_radical(Poly(x + t/2 + 3, t), Poly(1, t), DE) == \ ([(t0, 2), (x, 1)], x*t0**2, 2, 3) def test_is_deriv_k(): DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(1/x, t1), Poly(1/(x + 1), t2)], 'exts': [None, 'log', 'log'], 'extargs': [None, x, x + 1]}) assert is_deriv_k(Poly(2*x**2 + 2*x, t2), Poly(1, t2), DE) == \ ([(t1, 1), (t2, 1)], t1 + t2, 2) DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(1/x, t1), Poly(t2, t2)], 'exts': [None, 'log', 'exp'], 'extargs': [None, x, x]}) assert is_deriv_k(Poly(x**2*t2**3, t2), Poly(1, t2), DE) == \ ([(x, 3), (t1, 2)], 2*t1 + 3*x, 1) # TODO: Add more tests, including ones with exponentials DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(2/x, t1)], 'exts': [None, 'log'], 'extargs': [None, x**2]}) assert is_deriv_k(Poly(x, t1), Poly(1, t1), DE) == \ ([(t1, S.Half)], t1/2, 1) DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(2/(1 + x), t0)], 'exts': [None, 'log'], 'extargs': [None, x**2 + 2*x + 1]}) assert is_deriv_k(Poly(1 + x, t0), Poly(1, t0), DE) == \ ([(t0, S.Half)], t0/2, 1) # Issue 10798 # DE = DifferentialExtension(log(1/x), x) DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(-1/x, t)], 'exts': [None, 'log'], 'extargs': [None, 1/x]}) assert is_deriv_k(Poly(1, t), Poly(x, t), DE) == ([(t, 1)], t, 1) def test_is_log_deriv_k_t_radical_in_field(): # NOTE: any potential constant factor in the second element of the result # doesn't matter, because it cancels in Da/a. DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(1/x, t)]}) assert is_log_deriv_k_t_radical_in_field(Poly(5*t + 1, t), Poly(2*t*x, t), DE) == \ (2, t*x**5) assert is_log_deriv_k_t_radical_in_field(Poly(2 + 3*t, t), Poly(5*x*t, t), DE) == \ (5, x**3*t**2) DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(-t/x**2, t)]}) assert is_log_deriv_k_t_radical_in_field(Poly(-(1 + 2*t), t), Poly(2*x**2 + 2*x**2*t, t), DE) == \ (2, t + t**2) assert is_log_deriv_k_t_radical_in_field(Poly(-1, t), Poly(x**2, t), DE) == \ (1, t) assert is_log_deriv_k_t_radical_in_field(Poly(1, t), Poly(2*x**2, t), DE) == \ (2, 1/t) def test_parametric_log_deriv(): DE = DifferentialExtension(extension={'D': [Poly(1, x), Poly(1/x, t)]}) assert parametric_log_deriv_heu(Poly(5*t**2 + t - 6, t), Poly(2*x*t**2, t), Poly(-1, t), Poly(x*t**2, t), DE) == \ (2, 6, t*x**5)
0c0801bf2f88f9723dc3d16f15e5d3bca96c0ab350462f8edf64d4cfd0544501
from sympy import (Add, Basic, Expr, S, Symbol, Wild, Float, Integer, Rational, I, sin, cos, tan, exp, log, nan, oo, sqrt, symbols, Integral, sympify, WildFunction, Poly, Function, Derivative, Number, pi, NumberSymbol, zoo, Piecewise, Mul, Pow, nsimplify, ratsimp, trigsimp, radsimp, powsimp, simplify, together, collect, factorial, apart, combsimp, factor, refine, cancel, Tuple, default_sort_key, DiracDelta, gamma, Dummy, Sum, E, exp_polar, expand, diff, O, Heaviside, Si, Max, UnevaluatedExpr, integrate, gammasimp, Gt) from sympy.core.expr import ExprBuilder, unchanged from sympy.core.function import AppliedUndef from sympy.physics.secondquant import FockState from sympy.physics.units import meter from sympy.testing.pytest import raises, XFAIL from sympy.abc import a, b, c, n, t, u, x, y, z class DummyNumber: """ Minimal implementation of a number that works with SymPy. If one has a Number class (e.g. Sage Integer, or some other custom class) that one wants to work well with SymPy, one has to implement at least the methods of this class DummyNumber, resp. its subclasses I5 and F1_1. Basically, one just needs to implement either __int__() or __float__() and then one needs to make sure that the class works with Python integers and with itself. """ def __radd__(self, a): if isinstance(a, (int, float)): return a + self.number return NotImplemented def __add__(self, a): if isinstance(a, (int, float, DummyNumber)): return self.number + a return NotImplemented def __rsub__(self, a): if isinstance(a, (int, float)): return a - self.number return NotImplemented def __sub__(self, a): if isinstance(a, (int, float, DummyNumber)): return self.number - a return NotImplemented def __rmul__(self, a): if isinstance(a, (int, float)): return a * self.number return NotImplemented def __mul__(self, a): if isinstance(a, (int, float, DummyNumber)): return self.number * a return NotImplemented def __rtruediv__(self, a): if isinstance(a, (int, float)): return a / self.number return NotImplemented def __truediv__(self, a): if isinstance(a, (int, float, DummyNumber)): return self.number / a return NotImplemented def __rpow__(self, a): if isinstance(a, (int, float)): return a ** self.number return NotImplemented def __pow__(self, a): if isinstance(a, (int, float, DummyNumber)): return self.number ** a return NotImplemented def __pos__(self): return self.number def __neg__(self): return - self.number class I5(DummyNumber): number = 5 def __int__(self): return self.number class F1_1(DummyNumber): number = 1.1 def __float__(self): return self.number i5 = I5() f1_1 = F1_1() # basic sympy objects basic_objs = [ Rational(2), Float("1.3"), x, y, pow(x, y)*y, ] # all supported objects all_objs = basic_objs + [ 5, 5.5, i5, f1_1 ] def dotest(s): for xo in all_objs: for yo in all_objs: s(xo, yo) return True def test_basic(): def j(a, b): x = a x = +a x = -a x = a + b x = a - b x = a*b x = a/b x = a**b del x assert dotest(j) def test_ibasic(): def s(a, b): x = a x += b x = a x -= b x = a x *= b x = a x /= b assert dotest(s) class NonBasic: '''This class represents an object that knows how to implement binary operations like +, -, etc with Expr but is not a subclass of Basic itself. The NonExpr subclass below does subclass Basic but not Expr. For both NonBasic and NonExpr it should be possible for them to override Expr.__add__ etc because Expr.__add__ should be returning NotImplemented for non Expr classes. Otherwise Expr.__add__ would create meaningless objects like Add(Integer(1), FiniteSet(2)) and it wouldn't be possible for other classes to override these operations when interacting with Expr. ''' def __add__(self, other): return SpecialOp('+', self, other) def __radd__(self, other): return SpecialOp('+', other, self) def __sub__(self, other): return SpecialOp('-', self, other) def __rsub__(self, other): return SpecialOp('-', other, self) def __mul__(self, other): return SpecialOp('*', self, other) def __rmul__(self, other): return SpecialOp('*', other, self) def __truediv__(self, other): return SpecialOp('/', self, other) def __rtruediv__(self, other): return SpecialOp('/', other, self) def __floordiv__(self, other): return SpecialOp('//', self, other) def __rfloordiv__(self, other): return SpecialOp('//', other, self) def __mod__(self, other): return SpecialOp('%', self, other) def __rmod__(self, other): return SpecialOp('%', other, self) def __divmod__(self, other): return SpecialOp('divmod', self, other) def __rdivmod__(self, other): return SpecialOp('divmod', other, self) def __pow__(self, other): return SpecialOp('**', self, other) def __rpow__(self, other): return SpecialOp('**', other, self) def __lt__(self, other): return SpecialOp('<', self, other) def __gt__(self, other): return SpecialOp('>', self, other) def __le__(self, other): return SpecialOp('<=', self, other) def __ge__(self, other): return SpecialOp('>=', self, other) class NonExpr(Basic, NonBasic): '''Like NonBasic above except this is a subclass of Basic but not Expr''' pass class SpecialOp(Basic): '''Represents the results of operations with NonBasic and NonExpr''' def __new__(cls, op, arg1, arg2): return Basic.__new__(cls, op, arg1, arg2) class NonArithmetic(Basic): '''Represents a Basic subclass that does not support arithmetic operations''' pass def test_cooperative_operations(): '''Tests that Expr uses binary operations cooperatively. In particular it should be possible for non-Expr classes to override binary operators like +, - etc when used with Expr instances. This should work for non-Expr classes whether they are Basic subclasses or not. Also non-Expr classes that do not define binary operators with Expr should give TypeError. ''' # A bunch of instances of Expr subclasses exprs = [ Expr(), S.Zero, S.One, S.Infinity, S.NegativeInfinity, S.ComplexInfinity, S.Half, Float(0.5), Integer(2), Symbol('x'), Mul(2, Symbol('x')), Add(2, Symbol('x')), Pow(2, Symbol('x')), ] for e in exprs: # Test that these classes can override arithmetic operations in # combination with various Expr types. for ne in [NonBasic(), NonExpr()]: results = [ (ne + e, ('+', ne, e)), (e + ne, ('+', e, ne)), (ne - e, ('-', ne, e)), (e - ne, ('-', e, ne)), (ne * e, ('*', ne, e)), (e * ne, ('*', e, ne)), (ne / e, ('/', ne, e)), (e / ne, ('/', e, ne)), (ne // e, ('//', ne, e)), (e // ne, ('//', e, ne)), (ne % e, ('%', ne, e)), (e % ne, ('%', e, ne)), (divmod(ne, e), ('divmod', ne, e)), (divmod(e, ne), ('divmod', e, ne)), (ne ** e, ('**', ne, e)), (e ** ne, ('**', e, ne)), (e < ne, ('>', ne, e)), (ne < e, ('<', ne, e)), (e > ne, ('<', ne, e)), (ne > e, ('>', ne, e)), (e <= ne, ('>=', ne, e)), (ne <= e, ('<=', ne, e)), (e >= ne, ('<=', ne, e)), (ne >= e, ('>=', ne, e)), ] for res, args in results: assert type(res) is SpecialOp and res.args == args # These classes do not support binary operators with Expr. Every # operation should raise in combination with any of the Expr types. for na in [NonArithmetic(), object()]: raises(TypeError, lambda : e + na) raises(TypeError, lambda : na + e) raises(TypeError, lambda : e - na) raises(TypeError, lambda : na - e) raises(TypeError, lambda : e * na) raises(TypeError, lambda : na * e) raises(TypeError, lambda : e / na) raises(TypeError, lambda : na / e) raises(TypeError, lambda : e // na) raises(TypeError, lambda : na // e) raises(TypeError, lambda : e % na) raises(TypeError, lambda : na % e) raises(TypeError, lambda : divmod(e, na)) raises(TypeError, lambda : divmod(na, e)) raises(TypeError, lambda : e ** na) raises(TypeError, lambda : na ** e) raises(TypeError, lambda : e > na) raises(TypeError, lambda : na > e) raises(TypeError, lambda : e < na) raises(TypeError, lambda : na < e) raises(TypeError, lambda : e >= na) raises(TypeError, lambda : na >= e) raises(TypeError, lambda : e <= na) raises(TypeError, lambda : na <= e) def test_relational(): from sympy import Lt assert (pi < 3) is S.false assert (pi <= 3) is S.false assert (pi > 3) is S.true assert (pi >= 3) is S.true assert (-pi < 3) is S.true assert (-pi <= 3) is S.true assert (-pi > 3) is S.false assert (-pi >= 3) is S.false r = Symbol('r', real=True) assert (r - 2 < r - 3) is S.false assert Lt(x + I, x + I + 2).func == Lt # issue 8288 def test_relational_assumptions(): from sympy import Lt, Gt, Le, Ge m1 = Symbol("m1", nonnegative=False) m2 = Symbol("m2", positive=False) m3 = Symbol("m3", nonpositive=False) m4 = Symbol("m4", negative=False) assert (m1 < 0) == Lt(m1, 0) assert (m2 <= 0) == Le(m2, 0) assert (m3 > 0) == Gt(m3, 0) assert (m4 >= 0) == Ge(m4, 0) m1 = Symbol("m1", nonnegative=False, real=True) m2 = Symbol("m2", positive=False, real=True) m3 = Symbol("m3", nonpositive=False, real=True) m4 = Symbol("m4", negative=False, real=True) assert (m1 < 0) is S.true assert (m2 <= 0) is S.true assert (m3 > 0) is S.true assert (m4 >= 0) is S.true m1 = Symbol("m1", negative=True) m2 = Symbol("m2", nonpositive=True) m3 = Symbol("m3", positive=True) m4 = Symbol("m4", nonnegative=True) assert (m1 < 0) is S.true assert (m2 <= 0) is S.true assert (m3 > 0) is S.true assert (m4 >= 0) is S.true m1 = Symbol("m1", negative=False, real=True) m2 = Symbol("m2", nonpositive=False, real=True) m3 = Symbol("m3", positive=False, real=True) m4 = Symbol("m4", nonnegative=False, real=True) assert (m1 < 0) is S.false assert (m2 <= 0) is S.false assert (m3 > 0) is S.false assert (m4 >= 0) is S.false # See https://github.com/sympy/sympy/issues/17708 #def test_relational_noncommutative(): # from sympy import Lt, Gt, Le, Ge # A, B = symbols('A,B', commutative=False) # assert (A < B) == Lt(A, B) # assert (A <= B) == Le(A, B) # assert (A > B) == Gt(A, B) # assert (A >= B) == Ge(A, B) def test_basic_nostr(): for obj in basic_objs: raises(TypeError, lambda: obj + '1') raises(TypeError, lambda: obj - '1') if obj == 2: assert obj * '1' == '11' else: raises(TypeError, lambda: obj * '1') raises(TypeError, lambda: obj / '1') raises(TypeError, lambda: obj ** '1') def test_series_expansion_for_uniform_order(): assert (1/x + y + x).series(x, 0, 0) == 1/x + O(1, x) assert (1/x + y + x).series(x, 0, 1) == 1/x + y + O(x) assert (1/x + 1 + x).series(x, 0, 0) == 1/x + O(1, x) assert (1/x + 1 + x).series(x, 0, 1) == 1/x + 1 + O(x) assert (1/x + x).series(x, 0, 0) == 1/x + O(1, x) assert (1/x + y + y*x + x).series(x, 0, 0) == 1/x + O(1, x) assert (1/x + y + y*x + x).series(x, 0, 1) == 1/x + y + O(x) def test_leadterm(): assert (3 + 2*x**(log(3)/log(2) - 1)).leadterm(x) == (3, 0) assert (1/x**2 + 1 + x + x**2).leadterm(x)[1] == -2 assert (1/x + 1 + x + x**2).leadterm(x)[1] == -1 assert (x**2 + 1/x).leadterm(x)[1] == -1 assert (1 + x**2).leadterm(x)[1] == 0 assert (x + 1).leadterm(x)[1] == 0 assert (x + x**2).leadterm(x)[1] == 1 assert (x**2).leadterm(x)[1] == 2 def test_as_leading_term(): assert (3 + 2*x**(log(3)/log(2) - 1)).as_leading_term(x) == 3 assert (1/x**2 + 1 + x + x**2).as_leading_term(x) == 1/x**2 assert (1/x + 1 + x + x**2).as_leading_term(x) == 1/x assert (x**2 + 1/x).as_leading_term(x) == 1/x assert (1 + x**2).as_leading_term(x) == 1 assert (x + 1).as_leading_term(x) == 1 assert (x + x**2).as_leading_term(x) == x assert (x**2).as_leading_term(x) == x**2 assert (x + oo).as_leading_term(x) is oo raises(ValueError, lambda: (x + 1).as_leading_term(1)) # https://github.com/sympy/sympy/issues/21177 f = -3*x + (x + Rational(3, 2) - sqrt(3)*S.ImaginaryUnit/2)**2\ - Rational(3, 2) + 3*sqrt(3)*S.ImaginaryUnit/2 assert f.as_leading_term(x) == \ (3*sqrt(3)*x - 3*S.ImaginaryUnit*x)/(sqrt(3) + 3*S.ImaginaryUnit) # https://github.com/sympy/sympy/issues/21245 f = 1 - x - x**2 fi = (1 + sqrt(5))/2 assert f.subs(x, y + 1/fi).as_leading_term(y) == \ (-36*sqrt(5)*y - 80*y)/(16*sqrt(5) + 36) def test_leadterm2(): assert (x*cos(1)*cos(1 + sin(1)) + sin(1 + sin(1))).leadterm(x) == \ (sin(1 + sin(1)), 0) def test_leadterm3(): assert (y + z + x).leadterm(x) == (y + z, 0) def test_as_leading_term2(): assert (x*cos(1)*cos(1 + sin(1)) + sin(1 + sin(1))).as_leading_term(x) == \ sin(1 + sin(1)) def test_as_leading_term3(): assert (2 + pi + x).as_leading_term(x) == 2 + pi assert (2*x + pi*x + x**2).as_leading_term(x) == 2*x + pi*x def test_as_leading_term4(): # see issue 6843 n = Symbol('n', integer=True, positive=True) r = -n**3/(2*n**2 + 4*n + 2) - n**2/(n**2 + 2*n + 1) + \ n**2/(n + 1) - n/(2*n**2 + 4*n + 2) + n/(n*x + x) + 2*n/(n + 1) - \ 1 + 1/(n*x + x) + 1/(n + 1) - 1/x assert r.as_leading_term(x).cancel() == n/2 def test_as_leading_term_stub(): class foo(Function): pass assert foo(1/x).as_leading_term(x) == foo(1/x) assert foo(1).as_leading_term(x) == foo(1) raises(NotImplementedError, lambda: foo(x).as_leading_term(x)) def test_as_leading_term_deriv_integral(): # related to issue 11313 assert Derivative(x ** 3, x).as_leading_term(x) == 3*x**2 assert Derivative(x ** 3, y).as_leading_term(x) == 0 assert Integral(x ** 3, x).as_leading_term(x) == x**4/4 assert Integral(x ** 3, y).as_leading_term(x) == y*x**3 assert Derivative(exp(x), x).as_leading_term(x) == 1 assert Derivative(log(x), x).as_leading_term(x) == (1/x).as_leading_term(x) def test_atoms(): assert x.atoms() == {x} assert (1 + x).atoms() == {x, S.One} assert (1 + 2*cos(x)).atoms(Symbol) == {x} assert (1 + 2*cos(x)).atoms(Symbol, Number) == {S.One, S(2), x} assert (2*(x**(y**x))).atoms() == {S(2), x, y} assert S.Half.atoms() == {S.Half} assert S.Half.atoms(Symbol) == set() assert sin(oo).atoms(oo) == set() assert Poly(0, x).atoms() == {S.Zero, x} assert Poly(1, x).atoms() == {S.One, x} assert Poly(x, x).atoms() == {x} assert Poly(x, x, y).atoms() == {x, y} assert Poly(x + y, x, y).atoms() == {x, y} assert Poly(x + y, x, y, z).atoms() == {x, y, z} assert Poly(x + y*t, x, y, z).atoms() == {t, x, y, z} assert (I*pi).atoms(NumberSymbol) == {pi} assert (I*pi).atoms(NumberSymbol, I) == \ (I*pi).atoms(I, NumberSymbol) == {pi, I} assert exp(exp(x)).atoms(exp) == {exp(exp(x)), exp(x)} assert (1 + x*(2 + y) + exp(3 + z)).atoms(Add) == \ {1 + x*(2 + y) + exp(3 + z), 2 + y, 3 + z} # issue 6132 f = Function('f') e = (f(x) + sin(x) + 2) assert e.atoms(AppliedUndef) == \ {f(x)} assert e.atoms(AppliedUndef, Function) == \ {f(x), sin(x)} assert e.atoms(Function) == \ {f(x), sin(x)} assert e.atoms(AppliedUndef, Number) == \ {f(x), S(2)} assert e.atoms(Function, Number) == \ {S(2), sin(x), f(x)} def test_is_polynomial(): k = Symbol('k', nonnegative=True, integer=True) assert Rational(2).is_polynomial(x, y, z) is True assert (S.Pi).is_polynomial(x, y, z) is True assert x.is_polynomial(x) is True assert x.is_polynomial(y) is True assert (x**2).is_polynomial(x) is True assert (x**2).is_polynomial(y) is True assert (x**(-2)).is_polynomial(x) is False assert (x**(-2)).is_polynomial(y) is True assert (2**x).is_polynomial(x) is False assert (2**x).is_polynomial(y) is True assert (x**k).is_polynomial(x) is False assert (x**k).is_polynomial(k) is False assert (x**x).is_polynomial(x) is False assert (k**k).is_polynomial(k) is False assert (k**x).is_polynomial(k) is False assert (x**(-k)).is_polynomial(x) is False assert ((2*x)**k).is_polynomial(x) is False assert (x**2 + 3*x - 8).is_polynomial(x) is True assert (x**2 + 3*x - 8).is_polynomial(y) is True assert (x**2 + 3*x - 8).is_polynomial() is True assert sqrt(x).is_polynomial(x) is False assert (sqrt(x)**3).is_polynomial(x) is False assert (x**2 + 3*x*sqrt(y) - 8).is_polynomial(x) is True assert (x**2 + 3*x*sqrt(y) - 8).is_polynomial(y) is False assert ((x**2)*(y**2) + x*(y**2) + y*x + exp(2)).is_polynomial() is True assert ((x**2)*(y**2) + x*(y**2) + y*x + exp(x)).is_polynomial() is False assert ( (x**2)*(y**2) + x*(y**2) + y*x + exp(2)).is_polynomial(x, y) is True assert ( (x**2)*(y**2) + x*(y**2) + y*x + exp(x)).is_polynomial(x, y) is False def test_is_rational_function(): assert Integer(1).is_rational_function() is True assert Integer(1).is_rational_function(x) is True assert Rational(17, 54).is_rational_function() is True assert Rational(17, 54).is_rational_function(x) is True assert (12/x).is_rational_function() is True assert (12/x).is_rational_function(x) is True assert (x/y).is_rational_function() is True assert (x/y).is_rational_function(x) is True assert (x/y).is_rational_function(x, y) is True assert (x**2 + 1/x/y).is_rational_function() is True assert (x**2 + 1/x/y).is_rational_function(x) is True assert (x**2 + 1/x/y).is_rational_function(x, y) is True assert (sin(y)/x).is_rational_function() is False assert (sin(y)/x).is_rational_function(y) is False assert (sin(y)/x).is_rational_function(x) is True assert (sin(y)/x).is_rational_function(x, y) is False assert (S.NaN).is_rational_function() is False assert (S.Infinity).is_rational_function() is False assert (S.NegativeInfinity).is_rational_function() is False assert (S.ComplexInfinity).is_rational_function() is False def test_is_meromorphic(): f = a/x**2 + b + x + c*x**2 assert f.is_meromorphic(x, 0) is True assert f.is_meromorphic(x, 1) is True assert f.is_meromorphic(x, zoo) is True g = 3 + 2*x**(log(3)/log(2) - 1) assert g.is_meromorphic(x, 0) is False assert g.is_meromorphic(x, 1) is True assert g.is_meromorphic(x, zoo) is False n = Symbol('n', integer=True) h = sin(1/x)**n*x assert h.is_meromorphic(x, 0) is False assert h.is_meromorphic(x, 1) is True assert h.is_meromorphic(x, zoo) is False e = log(x)**pi assert e.is_meromorphic(x, 0) is False assert e.is_meromorphic(x, 1) is False assert e.is_meromorphic(x, 2) is True assert e.is_meromorphic(x, zoo) is False assert (log(x)**a).is_meromorphic(x, 0) is False assert (log(x)**a).is_meromorphic(x, 1) is False assert (a**log(x)).is_meromorphic(x, 0) is None assert (3**log(x)).is_meromorphic(x, 0) is False assert (3**log(x)).is_meromorphic(x, 1) is True def test_is_algebraic_expr(): assert sqrt(3).is_algebraic_expr(x) is True assert sqrt(3).is_algebraic_expr() is True eq = ((1 + x**2)/(1 - y**2))**(S.One/3) assert eq.is_algebraic_expr(x) is True assert eq.is_algebraic_expr(y) is True assert (sqrt(x) + y**(S(2)/3)).is_algebraic_expr(x) is True assert (sqrt(x) + y**(S(2)/3)).is_algebraic_expr(y) is True assert (sqrt(x) + y**(S(2)/3)).is_algebraic_expr() is True assert (cos(y)/sqrt(x)).is_algebraic_expr() is False assert (cos(y)/sqrt(x)).is_algebraic_expr(x) is True assert (cos(y)/sqrt(x)).is_algebraic_expr(y) is False assert (cos(y)/sqrt(x)).is_algebraic_expr(x, y) is False def test_SAGE1(): #see https://github.com/sympy/sympy/issues/3346 class MyInt: def _sympy_(self): return Integer(5) m = MyInt() e = Rational(2)*m assert e == 10 raises(TypeError, lambda: Rational(2)*MyInt) def test_SAGE2(): class MyInt: def __int__(self): return 5 assert sympify(MyInt()) == 5 e = Rational(2)*MyInt() assert e == 10 raises(TypeError, lambda: Rational(2)*MyInt) def test_SAGE3(): class MySymbol: def __rmul__(self, other): return ('mys', other, self) o = MySymbol() e = x*o assert e == ('mys', x, o) def test_len(): e = x*y assert len(e.args) == 2 e = x + y + z assert len(e.args) == 3 def test_doit(): a = Integral(x**2, x) assert isinstance(a.doit(), Integral) is False assert isinstance(a.doit(integrals=True), Integral) is False assert isinstance(a.doit(integrals=False), Integral) is True assert (2*Integral(x, x)).doit() == x**2 def test_attribute_error(): raises(AttributeError, lambda: x.cos()) raises(AttributeError, lambda: x.sin()) raises(AttributeError, lambda: x.exp()) def test_args(): assert (x*y).args in ((x, y), (y, x)) assert (x + y).args in ((x, y), (y, x)) assert (x*y + 1).args in ((x*y, 1), (1, x*y)) assert sin(x*y).args == (x*y,) assert sin(x*y).args[0] == x*y assert (x**y).args == (x, y) assert (x**y).args[0] == x assert (x**y).args[1] == y def test_noncommutative_expand_issue_3757(): A, B, C = symbols('A,B,C', commutative=False) assert A*B - B*A != 0 assert (A*(A + B)*B).expand() == A**2*B + A*B**2 assert (A*(A + B + C)*B).expand() == A**2*B + A*B**2 + A*C*B def test_as_numer_denom(): a, b, c = symbols('a, b, c') assert nan.as_numer_denom() == (nan, 1) assert oo.as_numer_denom() == (oo, 1) assert (-oo).as_numer_denom() == (-oo, 1) assert zoo.as_numer_denom() == (zoo, 1) assert (-zoo).as_numer_denom() == (zoo, 1) assert x.as_numer_denom() == (x, 1) assert (1/x).as_numer_denom() == (1, x) assert (x/y).as_numer_denom() == (x, y) assert (x/2).as_numer_denom() == (x, 2) assert (x*y/z).as_numer_denom() == (x*y, z) assert (x/(y*z)).as_numer_denom() == (x, y*z) assert S.Half.as_numer_denom() == (1, 2) assert (1/y**2).as_numer_denom() == (1, y**2) assert (x/y**2).as_numer_denom() == (x, y**2) assert ((x**2 + 1)/y).as_numer_denom() == (x**2 + 1, y) assert (x*(y + 1)/y**7).as_numer_denom() == (x*(y + 1), y**7) assert (x**-2).as_numer_denom() == (1, x**2) assert (a/x + b/2/x + c/3/x).as_numer_denom() == \ (6*a + 3*b + 2*c, 6*x) assert (a/x + b/2/x + c/3/y).as_numer_denom() == \ (2*c*x + y*(6*a + 3*b), 6*x*y) assert (a/x + b/2/x + c/.5/x).as_numer_denom() == \ (2*a + b + 4.0*c, 2*x) # this should take no more than a few seconds assert int(log(Add(*[Dummy()/i/x for i in range(1, 705)] ).as_numer_denom()[1]/x).n(4)) == 705 for i in [S.Infinity, S.NegativeInfinity, S.ComplexInfinity]: assert (i + x/3).as_numer_denom() == \ (x + i, 3) assert (S.Infinity + x/3 + y/4).as_numer_denom() == \ (4*x + 3*y + S.Infinity, 12) assert (oo*x + zoo*y).as_numer_denom() == \ (zoo*y + oo*x, 1) A, B, C = symbols('A,B,C', commutative=False) assert (A*B*C**-1).as_numer_denom() == (A*B*C**-1, 1) assert (A*B*C**-1/x).as_numer_denom() == (A*B*C**-1, x) assert (C**-1*A*B).as_numer_denom() == (C**-1*A*B, 1) assert (C**-1*A*B/x).as_numer_denom() == (C**-1*A*B, x) assert ((A*B*C)**-1).as_numer_denom() == ((A*B*C)**-1, 1) assert ((A*B*C)**-1/x).as_numer_denom() == ((A*B*C)**-1, x) def test_trunc(): import math x, y = symbols('x y') assert math.trunc(2) == 2 assert math.trunc(4.57) == 4 assert math.trunc(-5.79) == -5 assert math.trunc(pi) == 3 assert math.trunc(log(7)) == 1 assert math.trunc(exp(5)) == 148 assert math.trunc(cos(pi)) == -1 assert math.trunc(sin(5)) == 0 raises(TypeError, lambda: math.trunc(x)) raises(TypeError, lambda: math.trunc(x + y**2)) raises(TypeError, lambda: math.trunc(oo)) def test_as_independent(): assert S.Zero.as_independent(x, as_Add=True) == (0, 0) assert S.Zero.as_independent(x, as_Add=False) == (0, 0) assert (2*x*sin(x) + y + x).as_independent(x) == (y, x + 2*x*sin(x)) assert (2*x*sin(x) + y + x).as_independent(y) == (x + 2*x*sin(x), y) assert (2*x*sin(x) + y + x).as_independent(x, y) == (0, y + x + 2*x*sin(x)) assert (x*sin(x)*cos(y)).as_independent(x) == (cos(y), x*sin(x)) assert (x*sin(x)*cos(y)).as_independent(y) == (x*sin(x), cos(y)) assert (x*sin(x)*cos(y)).as_independent(x, y) == (1, x*sin(x)*cos(y)) assert (sin(x)).as_independent(x) == (1, sin(x)) assert (sin(x)).as_independent(y) == (sin(x), 1) assert (2*sin(x)).as_independent(x) == (2, sin(x)) assert (2*sin(x)).as_independent(y) == (2*sin(x), 1) # issue 4903 = 1766b n1, n2, n3 = symbols('n1 n2 n3', commutative=False) assert (n1 + n1*n2).as_independent(n2) == (n1, n1*n2) assert (n2*n1 + n1*n2).as_independent(n2) == (0, n1*n2 + n2*n1) assert (n1*n2*n1).as_independent(n2) == (n1, n2*n1) assert (n1*n2*n1).as_independent(n1) == (1, n1*n2*n1) assert (3*x).as_independent(x, as_Add=True) == (0, 3*x) assert (3*x).as_independent(x, as_Add=False) == (3, x) assert (3 + x).as_independent(x, as_Add=True) == (3, x) assert (3 + x).as_independent(x, as_Add=False) == (1, 3 + x) # issue 5479 assert (3*x).as_independent(Symbol) == (3, x) # issue 5648 assert (n1*x*y).as_independent(x) == (n1*y, x) assert ((x + n1)*(x - y)).as_independent(x) == (1, (x + n1)*(x - y)) assert ((x + n1)*(x - y)).as_independent(y) == (x + n1, x - y) assert (DiracDelta(x - n1)*DiracDelta(x - y)).as_independent(x) \ == (1, DiracDelta(x - n1)*DiracDelta(x - y)) assert (x*y*n1*n2*n3).as_independent(n2) == (x*y*n1, n2*n3) assert (x*y*n1*n2*n3).as_independent(n1) == (x*y, n1*n2*n3) assert (x*y*n1*n2*n3).as_independent(n3) == (x*y*n1*n2, n3) assert (DiracDelta(x - n1)*DiracDelta(y - n1)*DiracDelta(x - n2)).as_independent(y) == \ (DiracDelta(x - n1)*DiracDelta(x - n2), DiracDelta(y - n1)) # issue 5784 assert (x + Integral(x, (x, 1, 2))).as_independent(x, strict=True) == \ (Integral(x, (x, 1, 2)), x) eq = Add(x, -x, 2, -3, evaluate=False) assert eq.as_independent(x) == (-1, Add(x, -x, evaluate=False)) eq = Mul(x, 1/x, 2, -3, evaluate=False) eq.as_independent(x) == (-6, Mul(x, 1/x, evaluate=False)) assert (x*y).as_independent(z, as_Add=True) == (x*y, 0) @XFAIL def test_call_2(): # TODO UndefinedFunction does not subclass Expr f = Function('f') assert (2*f)(x) == 2*f(x) def test_replace(): f = log(sin(x)) + tan(sin(x**2)) assert f.replace(sin, cos) == log(cos(x)) + tan(cos(x**2)) assert f.replace( sin, lambda a: sin(2*a)) == log(sin(2*x)) + tan(sin(2*x**2)) a = Wild('a') b = Wild('b') assert f.replace(sin(a), cos(a)) == log(cos(x)) + tan(cos(x**2)) assert f.replace( sin(a), lambda a: sin(2*a)) == log(sin(2*x)) + tan(sin(2*x**2)) # test exact assert (2*x).replace(a*x + b, b - a, exact=True) == 2*x assert (2*x).replace(a*x + b, b - a) == 2*x assert (2*x).replace(a*x + b, b - a, exact=False) == 2/x assert (2*x).replace(a*x + b, lambda a, b: b - a, exact=True) == 2*x assert (2*x).replace(a*x + b, lambda a, b: b - a) == 2*x assert (2*x).replace(a*x + b, lambda a, b: b - a, exact=False) == 2/x g = 2*sin(x**3) assert g.replace( lambda expr: expr.is_Number, lambda expr: expr**2) == 4*sin(x**9) assert cos(x).replace(cos, sin, map=True) == (sin(x), {cos(x): sin(x)}) assert sin(x).replace(cos, sin) == sin(x) cond, func = lambda x: x.is_Mul, lambda x: 2*x assert (x*y).replace(cond, func, map=True) == (2*x*y, {x*y: 2*x*y}) assert (x*(1 + x*y)).replace(cond, func, map=True) == \ (2*x*(2*x*y + 1), {x*(2*x*y + 1): 2*x*(2*x*y + 1), x*y: 2*x*y}) assert (y*sin(x)).replace(sin, lambda expr: sin(expr)/y, map=True) == \ (sin(x), {sin(x): sin(x)/y}) # if not simultaneous then y*sin(x) -> y*sin(x)/y = sin(x) -> sin(x)/y assert (y*sin(x)).replace(sin, lambda expr: sin(expr)/y, simultaneous=False) == sin(x)/y assert (x**2 + O(x**3)).replace(Pow, lambda b, e: b**e/e ) == x**2/2 + O(x**3) assert (x**2 + O(x**3)).replace(Pow, lambda b, e: b**e/e, simultaneous=False) == x**2/2 + O(x**3) assert (x*(x*y + 3)).replace(lambda x: x.is_Mul, lambda x: 2 + x) == \ x*(x*y + 5) + 2 e = (x*y + 1)*(2*x*y + 1) + 1 assert e.replace(cond, func, map=True) == ( 2*((2*x*y + 1)*(4*x*y + 1)) + 1, {2*x*y: 4*x*y, x*y: 2*x*y, (2*x*y + 1)*(4*x*y + 1): 2*((2*x*y + 1)*(4*x*y + 1))}) assert x.replace(x, y) == y assert (x + 1).replace(1, 2) == x + 2 # https://groups.google.com/forum/#!topic/sympy/8wCgeC95tz0 n1, n2, n3 = symbols('n1:4', commutative=False) f = Function('f') assert (n1*f(n2)).replace(f, lambda x: x) == n1*n2 assert (n3*f(n2)).replace(f, lambda x: x) == n3*n2 # issue 16725 assert S.Zero.replace(Wild('x'), 1) == 1 # let the user override the default decision of False assert S.Zero.replace(Wild('x'), 1, exact=True) == 0 def test_find(): expr = (x + y + 2 + sin(3*x)) assert expr.find(lambda u: u.is_Integer) == {S(2), S(3)} assert expr.find(lambda u: u.is_Symbol) == {x, y} assert expr.find(lambda u: u.is_Integer, group=True) == {S(2): 1, S(3): 1} assert expr.find(lambda u: u.is_Symbol, group=True) == {x: 2, y: 1} assert expr.find(Integer) == {S(2), S(3)} assert expr.find(Symbol) == {x, y} assert expr.find(Integer, group=True) == {S(2): 1, S(3): 1} assert expr.find(Symbol, group=True) == {x: 2, y: 1} a = Wild('a') expr = sin(sin(x)) + sin(x) + cos(x) + x assert expr.find(lambda u: type(u) is sin) == {sin(x), sin(sin(x))} assert expr.find( lambda u: type(u) is sin, group=True) == {sin(x): 2, sin(sin(x)): 1} assert expr.find(sin(a)) == {sin(x), sin(sin(x))} assert expr.find(sin(a), group=True) == {sin(x): 2, sin(sin(x)): 1} assert expr.find(sin) == {sin(x), sin(sin(x))} assert expr.find(sin, group=True) == {sin(x): 2, sin(sin(x)): 1} def test_count(): expr = (x + y + 2 + sin(3*x)) assert expr.count(lambda u: u.is_Integer) == 2 assert expr.count(lambda u: u.is_Symbol) == 3 assert expr.count(Integer) == 2 assert expr.count(Symbol) == 3 assert expr.count(2) == 1 a = Wild('a') assert expr.count(sin) == 1 assert expr.count(sin(a)) == 1 assert expr.count(lambda u: type(u) is sin) == 1 f = Function('f') assert f(x).count(f(x)) == 1 assert f(x).diff(x).count(f(x)) == 1 assert f(x).diff(x).count(x) == 2 def test_has_basics(): f = Function('f') g = Function('g') p = Wild('p') assert sin(x).has(x) assert sin(x).has(sin) assert not sin(x).has(y) assert not sin(x).has(cos) assert f(x).has(x) assert f(x).has(f) assert not f(x).has(y) assert not f(x).has(g) assert f(x).diff(x).has(x) assert f(x).diff(x).has(f) assert f(x).diff(x).has(Derivative) assert not f(x).diff(x).has(y) assert not f(x).diff(x).has(g) assert not f(x).diff(x).has(sin) assert (x**2).has(Symbol) assert not (x**2).has(Wild) assert (2*p).has(Wild) assert not x.has() def test_has_multiple(): f = x**2*y + sin(2**t + log(z)) assert f.has(x) assert f.has(y) assert f.has(z) assert f.has(t) assert not f.has(u) assert f.has(x, y, z, t) assert f.has(x, y, z, t, u) i = Integer(4400) assert not i.has(x) assert (i*x**i).has(x) assert not (i*y**i).has(x) assert (i*y**i).has(x, y) assert not (i*y**i).has(x, z) def test_has_piecewise(): f = (x*y + 3/y)**(3 + 2) g = Function('g') h = Function('h') p = Piecewise((g(x), x < -1), (1, x <= 1), (f, True)) assert p.has(x) assert p.has(y) assert not p.has(z) assert p.has(1) assert p.has(3) assert not p.has(4) assert p.has(f) assert p.has(g) assert not p.has(h) def test_has_iterative(): A, B, C = symbols('A,B,C', commutative=False) f = x*gamma(x)*sin(x)*exp(x*y)*A*B*C*cos(x*A*B) assert f.has(x) assert f.has(x*y) assert f.has(x*sin(x)) assert not f.has(x*sin(y)) assert f.has(x*A) assert f.has(x*A*B) assert not f.has(x*A*C) assert f.has(x*A*B*C) assert not f.has(x*A*C*B) assert f.has(x*sin(x)*A*B*C) assert not f.has(x*sin(x)*A*C*B) assert not f.has(x*sin(y)*A*B*C) assert f.has(x*gamma(x)) assert not f.has(x + sin(x)) assert (x & y & z).has(x & z) def test_has_integrals(): f = Integral(x**2 + sin(x*y*z), (x, 0, x + y + z)) assert f.has(x + y) assert f.has(x + z) assert f.has(y + z) assert f.has(x*y) assert f.has(x*z) assert f.has(y*z) assert not f.has(2*x + y) assert not f.has(2*x*y) def test_has_tuple(): f = Function('f') g = Function('g') h = Function('h') assert Tuple(x, y).has(x) assert not Tuple(x, y).has(z) assert Tuple(f(x), g(x)).has(x) assert not Tuple(f(x), g(x)).has(y) assert Tuple(f(x), g(x)).has(f) assert Tuple(f(x), g(x)).has(f(x)) assert not Tuple(f, g).has(x) assert Tuple(f, g).has(f) assert not Tuple(f, g).has(h) assert Tuple(True).has(True) is True # .has(1) will also be True def test_has_units(): from sympy.physics.units import m, s assert (x*m/s).has(x) assert (x*m/s).has(y, z) is False def test_has_polys(): poly = Poly(x**2 + x*y*sin(z), x, y, t) assert poly.has(x) assert poly.has(x, y, z) assert poly.has(x, y, z, t) def test_has_physics(): assert FockState((x, y)).has(x) def test_as_poly_as_expr(): f = x**2 + 2*x*y assert f.as_poly().as_expr() == f assert f.as_poly(x, y).as_expr() == f assert (f + sin(x)).as_poly(x, y) is None p = Poly(f, x, y) assert p.as_poly() == p raises(AttributeError, lambda: Tuple(x, x).as_poly(x)) raises(AttributeError, lambda: Tuple(x ** 2, x, y).as_poly(x)) def test_nonzero(): assert bool(S.Zero) is False assert bool(S.One) is True assert bool(x) is True assert bool(x + y) is True assert bool(x - x) is False assert bool(x*y) is True assert bool(x*1) is True assert bool(x*0) is False def test_is_number(): assert Float(3.14).is_number is True assert Integer(737).is_number is True assert Rational(3, 2).is_number is True assert Rational(8).is_number is True assert x.is_number is False assert (2*x).is_number is False assert (x + y).is_number is False assert log(2).is_number is True assert log(x).is_number is False assert (2 + log(2)).is_number is True assert (8 + log(2)).is_number is True assert (2 + log(x)).is_number is False assert (8 + log(2) + x).is_number is False assert (1 + x**2/x - x).is_number is True assert Tuple(Integer(1)).is_number is False assert Add(2, x).is_number is False assert Mul(3, 4).is_number is True assert Pow(log(2), 2).is_number is True assert oo.is_number is True g = WildFunction('g') assert g.is_number is False assert (2*g).is_number is False assert (x**2).subs(x, 3).is_number is True # test extensibility of .is_number # on subinstances of Basic class A(Basic): pass a = A() assert a.is_number is False def test_as_coeff_add(): assert S(2).as_coeff_add() == (2, ()) assert S(3.0).as_coeff_add() == (0, (S(3.0),)) assert S(-3.0).as_coeff_add() == (0, (S(-3.0),)) assert x.as_coeff_add() == (0, (x,)) assert (x - 1).as_coeff_add() == (-1, (x,)) assert (x + 1).as_coeff_add() == (1, (x,)) assert (x + 2).as_coeff_add() == (2, (x,)) assert (x + y).as_coeff_add(y) == (x, (y,)) assert (3*x).as_coeff_add(y) == (3*x, ()) # don't do expansion e = (x + y)**2 assert e.as_coeff_add(y) == (0, (e,)) def test_as_coeff_mul(): assert S(2).as_coeff_mul() == (2, ()) assert S(3.0).as_coeff_mul() == (1, (S(3.0),)) assert S(-3.0).as_coeff_mul() == (-1, (S(3.0),)) assert S(-3.0).as_coeff_mul(rational=False) == (-S(3.0), ()) assert x.as_coeff_mul() == (1, (x,)) assert (-x).as_coeff_mul() == (-1, (x,)) assert (2*x).as_coeff_mul() == (2, (x,)) assert (x*y).as_coeff_mul(y) == (x, (y,)) assert (3 + x).as_coeff_mul() == (1, (3 + x,)) assert (3 + x).as_coeff_mul(y) == (3 + x, ()) # don't do expansion e = exp(x + y) assert e.as_coeff_mul(y) == (1, (e,)) e = 2**(x + y) assert e.as_coeff_mul(y) == (1, (e,)) assert (1.1*x).as_coeff_mul(rational=False) == (1.1, (x,)) assert (1.1*x).as_coeff_mul() == (1, (1.1, x)) assert (-oo*x).as_coeff_mul(rational=True) == (-1, (oo, x)) def test_as_coeff_exponent(): assert (3*x**4).as_coeff_exponent(x) == (3, 4) assert (2*x**3).as_coeff_exponent(x) == (2, 3) assert (4*x**2).as_coeff_exponent(x) == (4, 2) assert (6*x**1).as_coeff_exponent(x) == (6, 1) assert (3*x**0).as_coeff_exponent(x) == (3, 0) assert (2*x**0).as_coeff_exponent(x) == (2, 0) assert (1*x**0).as_coeff_exponent(x) == (1, 0) assert (0*x**0).as_coeff_exponent(x) == (0, 0) assert (-1*x**0).as_coeff_exponent(x) == (-1, 0) assert (-2*x**0).as_coeff_exponent(x) == (-2, 0) assert (2*x**3 + pi*x**3).as_coeff_exponent(x) == (2 + pi, 3) assert (x*log(2)/(2*x + pi*x)).as_coeff_exponent(x) == \ (log(2)/(2 + pi), 0) # issue 4784 D = Derivative f = Function('f') fx = D(f(x), x) assert fx.as_coeff_exponent(f(x)) == (fx, 0) def test_extractions(): assert ((x*y)**3).extract_multiplicatively(x**2 * y) == x*y**2 assert ((x*y)**3).extract_multiplicatively(x**4 * y) is None assert (2*x).extract_multiplicatively(2) == x assert (2*x).extract_multiplicatively(3) is None assert (2*x).extract_multiplicatively(-1) is None assert (S.Half*x).extract_multiplicatively(3) == x/6 assert (sqrt(x)).extract_multiplicatively(x) is None assert (sqrt(x)).extract_multiplicatively(1/x) is None assert x.extract_multiplicatively(-x) is None assert (-2 - 4*I).extract_multiplicatively(-2) == 1 + 2*I assert (-2 - 4*I).extract_multiplicatively(3) is None assert (-2*x - 4*y - 8).extract_multiplicatively(-2) == x + 2*y + 4 assert (-2*x*y - 4*x**2*y).extract_multiplicatively(-2*y) == 2*x**2 + x assert (2*x*y + 4*x**2*y).extract_multiplicatively(2*y) == 2*x**2 + x assert (-4*y**2*x).extract_multiplicatively(-3*y) is None assert (2*x).extract_multiplicatively(1) == 2*x assert (-oo).extract_multiplicatively(5) is -oo assert (oo).extract_multiplicatively(5) is oo assert ((x*y)**3).extract_additively(1) is None assert (x + 1).extract_additively(x) == 1 assert (x + 1).extract_additively(2*x) is None assert (x + 1).extract_additively(-x) is None assert (-x + 1).extract_additively(2*x) is None assert (2*x + 3).extract_additively(x) == x + 3 assert (2*x + 3).extract_additively(2) == 2*x + 1 assert (2*x + 3).extract_additively(3) == 2*x assert (2*x + 3).extract_additively(-2) is None assert (2*x + 3).extract_additively(3*x) is None assert (2*x + 3).extract_additively(2*x) == 3 assert x.extract_additively(0) == x assert S(2).extract_additively(x) is None assert S(2.).extract_additively(2) is S.Zero assert S(2*x + 3).extract_additively(x + 1) == x + 2 assert S(2*x + 3).extract_additively(y + 1) is None assert S(2*x - 3).extract_additively(x + 1) is None assert S(2*x - 3).extract_additively(y + z) is None assert ((a + 1)*x*4 + y).extract_additively(x).expand() == \ 4*a*x + 3*x + y assert ((a + 1)*x*4 + 3*y).extract_additively(x + 2*y).expand() == \ 4*a*x + 3*x + y assert (y*(x + 1)).extract_additively(x + 1) is None assert ((y + 1)*(x + 1) + 3).extract_additively(x + 1) == \ y*(x + 1) + 3 assert ((x + y)*(x + 1) + x + y + 3).extract_additively(x + y) == \ x*(x + y) + 3 assert (x + y + 2*((x + y)*(x + 1)) + 3).extract_additively((x + y)*(x + 1)) == \ x + y + (x + 1)*(x + y) + 3 assert ((y + 1)*(x + 2*y + 1) + 3).extract_additively(y + 1) == \ (x + 2*y)*(y + 1) + 3 n = Symbol("n", integer=True) assert (Integer(-3)).could_extract_minus_sign() is True assert (-n*x + x).could_extract_minus_sign() != \ (n*x - x).could_extract_minus_sign() assert (x - y).could_extract_minus_sign() != \ (-x + y).could_extract_minus_sign() assert (1 - x - y).could_extract_minus_sign() is True assert (1 - x + y).could_extract_minus_sign() is False assert ((-x - x*y)/y).could_extract_minus_sign() is True assert (-(x + x*y)/y).could_extract_minus_sign() is True assert ((x + x*y)/(-y)).could_extract_minus_sign() is True assert ((x + x*y)/y).could_extract_minus_sign() is False assert (x*(-x - x**3)).could_extract_minus_sign() is True assert ((-x - y)/(x + y)).could_extract_minus_sign() is True class sign_invariant(Function, Expr): nargs = 1 def __neg__(self): return self foo = sign_invariant(x) assert foo == -foo assert foo.could_extract_minus_sign() is False # The results of each of these will vary on different machines, e.g. # the first one might be False and the other (then) is true or vice versa, # so both are included. assert ((-x - y)/(x - y)).could_extract_minus_sign() is False or \ ((-x - y)/(y - x)).could_extract_minus_sign() is False assert (x - y).could_extract_minus_sign() is False assert (-x + y).could_extract_minus_sign() is True # check that result is canonical eq = (3*x + 15*y).extract_multiplicatively(3) assert eq.args == eq.func(*eq.args).args def test_nan_extractions(): for r in (1, 0, I, nan): assert nan.extract_additively(r) is None assert nan.extract_multiplicatively(r) is None def test_coeff(): assert (x + 1).coeff(x + 1) == 1 assert (3*x).coeff(0) == 0 assert (z*(1 + x)*x**2).coeff(1 + x) == z*x**2 assert (1 + 2*x*x**(1 + x)).coeff(x*x**(1 + x)) == 2 assert (1 + 2*x**(y + z)).coeff(x**(y + z)) == 2 assert (3 + 2*x + 4*x**2).coeff(1) == 0 assert (3 + 2*x + 4*x**2).coeff(-1) == 0 assert (3 + 2*x + 4*x**2).coeff(x) == 2 assert (3 + 2*x + 4*x**2).coeff(x**2) == 4 assert (3 + 2*x + 4*x**2).coeff(x**3) == 0 assert (-x/8 + x*y).coeff(x) == Rational(-1, 8) + y assert (-x/8 + x*y).coeff(-x) == S.One/8 assert (4*x).coeff(2*x) == 0 assert (2*x).coeff(2*x) == 1 assert (-oo*x).coeff(x*oo) == -1 assert (10*x).coeff(x, 0) == 0 assert (10*x).coeff(10*x, 0) == 0 n1, n2 = symbols('n1 n2', commutative=False) assert (n1*n2).coeff(n1) == 1 assert (n1*n2).coeff(n2) == n1 assert (n1*n2 + x*n1).coeff(n1) == 1 # 1*n1*(n2+x) assert (n2*n1 + x*n1).coeff(n1) == n2 + x assert (n2*n1 + x*n1**2).coeff(n1) == n2 assert (n1**x).coeff(n1) == 0 assert (n1*n2 + n2*n1).coeff(n1) == 0 assert (2*(n1 + n2)*n2).coeff(n1 + n2, right=1) == n2 assert (2*(n1 + n2)*n2).coeff(n1 + n2, right=0) == 2 f = Function('f') assert (2*f(x) + 3*f(x).diff(x)).coeff(f(x)) == 2 expr = z*(x + y)**2 expr2 = z*(x + y)**2 + z*(2*x + 2*y)**2 assert expr.coeff(z) == (x + y)**2 assert expr.coeff(x + y) == 0 assert expr2.coeff(z) == (x + y)**2 + (2*x + 2*y)**2 assert (x + y + 3*z).coeff(1) == x + y assert (-x + 2*y).coeff(-1) == x assert (x - 2*y).coeff(-1) == 2*y assert (3 + 2*x + 4*x**2).coeff(1) == 0 assert (-x - 2*y).coeff(2) == -y assert (x + sqrt(2)*x).coeff(sqrt(2)) == x assert (3 + 2*x + 4*x**2).coeff(x) == 2 assert (3 + 2*x + 4*x**2).coeff(x**2) == 4 assert (3 + 2*x + 4*x**2).coeff(x**3) == 0 assert (z*(x + y)**2).coeff((x + y)**2) == z assert (z*(x + y)**2).coeff(x + y) == 0 assert (2 + 2*x + (x + 1)*y).coeff(x + 1) == y assert (x + 2*y + 3).coeff(1) == x assert (x + 2*y + 3).coeff(x, 0) == 2*y + 3 assert (x**2 + 2*y + 3*x).coeff(x**2, 0) == 2*y + 3*x assert x.coeff(0, 0) == 0 assert x.coeff(x, 0) == 0 n, m, o, l = symbols('n m o l', commutative=False) assert n.coeff(n) == 1 assert y.coeff(n) == 0 assert (3*n).coeff(n) == 3 assert (2 + n).coeff(x*m) == 0 assert (2*x*n*m).coeff(x) == 2*n*m assert (2 + n).coeff(x*m*n + y) == 0 assert (2*x*n*m).coeff(3*n) == 0 assert (n*m + m*n*m).coeff(n) == 1 + m assert (n*m + m*n*m).coeff(n, right=True) == m # = (1 + m)*n*m assert (n*m + m*n).coeff(n) == 0 assert (n*m + o*m*n).coeff(m*n) == o assert (n*m + o*m*n).coeff(m*n, right=1) == 1 assert (n*m + n*m*n).coeff(n*m, right=1) == 1 + n # = n*m*(n + 1) assert (x*y).coeff(z, 0) == x*y def test_coeff2(): r, kappa = symbols('r, kappa') psi = Function("psi") g = 1/r**2 * (2*r*psi(r).diff(r, 1) + r**2 * psi(r).diff(r, 2)) g = g.expand() assert g.coeff(psi(r).diff(r)) == 2/r def test_coeff2_0(): r, kappa = symbols('r, kappa') psi = Function("psi") g = 1/r**2 * (2*r*psi(r).diff(r, 1) + r**2 * psi(r).diff(r, 2)) g = g.expand() assert g.coeff(psi(r).diff(r, 2)) == 1 def test_coeff_expand(): expr = z*(x + y)**2 expr2 = z*(x + y)**2 + z*(2*x + 2*y)**2 assert expr.coeff(z) == (x + y)**2 assert expr2.coeff(z) == (x + y)**2 + (2*x + 2*y)**2 def test_integrate(): assert x.integrate(x) == x**2/2 assert x.integrate((x, 0, 1)) == S.Half def test_as_base_exp(): assert x.as_base_exp() == (x, S.One) assert (x*y*z).as_base_exp() == (x*y*z, S.One) assert (x + y + z).as_base_exp() == (x + y + z, S.One) assert ((x + y)**z).as_base_exp() == (x + y, z) def test_issue_4963(): assert hasattr(Mul(x, y), "is_commutative") assert hasattr(Mul(x, y, evaluate=False), "is_commutative") assert hasattr(Pow(x, y), "is_commutative") assert hasattr(Pow(x, y, evaluate=False), "is_commutative") expr = Mul(Pow(2, 2, evaluate=False), 3, evaluate=False) + 1 assert hasattr(expr, "is_commutative") def test_action_verbs(): assert nsimplify(1/(exp(3*pi*x/5) + 1)) == \ (1/(exp(3*pi*x/5) + 1)).nsimplify() assert ratsimp(1/x + 1/y) == (1/x + 1/y).ratsimp() assert trigsimp(log(x), deep=True) == (log(x)).trigsimp(deep=True) assert radsimp(1/(2 + sqrt(2))) == (1/(2 + sqrt(2))).radsimp() assert radsimp(1/(a + b*sqrt(c)), symbolic=False) == \ (1/(a + b*sqrt(c))).radsimp(symbolic=False) assert powsimp(x**y*x**z*y**z, combine='all') == \ (x**y*x**z*y**z).powsimp(combine='all') assert (x**t*y**t).powsimp(force=True) == (x*y)**t assert simplify(x**y*x**z*y**z) == (x**y*x**z*y**z).simplify() assert together(1/x + 1/y) == (1/x + 1/y).together() assert collect(a*x**2 + b*x**2 + a*x - b*x + c, x) == \ (a*x**2 + b*x**2 + a*x - b*x + c).collect(x) assert apart(y/(y + 2)/(y + 1), y) == (y/(y + 2)/(y + 1)).apart(y) assert combsimp(y/(x + 2)/(x + 1)) == (y/(x + 2)/(x + 1)).combsimp() assert gammasimp(gamma(x)/gamma(x-5)) == (gamma(x)/gamma(x-5)).gammasimp() assert factor(x**2 + 5*x + 6) == (x**2 + 5*x + 6).factor() assert refine(sqrt(x**2)) == sqrt(x**2).refine() assert cancel((x**2 + 5*x + 6)/(x + 2)) == ((x**2 + 5*x + 6)/(x + 2)).cancel() def test_as_powers_dict(): assert x.as_powers_dict() == {x: 1} assert (x**y*z).as_powers_dict() == {x: y, z: 1} assert Mul(2, 2, evaluate=False).as_powers_dict() == {S(2): S(2)} assert (x*y).as_powers_dict()[z] == 0 assert (x + y).as_powers_dict()[z] == 0 def test_as_coefficients_dict(): check = [S.One, x, y, x*y, 1] assert [Add(3*x, 2*x, y, 3).as_coefficients_dict()[i] for i in check] == \ [3, 5, 1, 0, 3] assert [Add(3*x, 2*x, y, 3, evaluate=False).as_coefficients_dict()[i] for i in check] == [3, 5, 1, 0, 3] assert [(3*x*y).as_coefficients_dict()[i] for i in check] == \ [0, 0, 0, 3, 0] assert [(3.0*x*y).as_coefficients_dict()[i] for i in check] == \ [0, 0, 0, 3.0, 0] assert (3.0*x*y).as_coefficients_dict()[3.0*x*y] == 0 def test_args_cnc(): A = symbols('A', commutative=False) assert (x + A).args_cnc() == \ [[], [x + A]] assert (x + a).args_cnc() == \ [[a + x], []] assert (x*a).args_cnc() == \ [[a, x], []] assert (x*y*A*(A + 1)).args_cnc(cset=True) == \ [{x, y}, [A, 1 + A]] assert Mul(x, x, evaluate=False).args_cnc(cset=True, warn=False) == \ [{x}, []] assert Mul(x, x**2, evaluate=False).args_cnc(cset=True, warn=False) == \ [{x, x**2}, []] raises(ValueError, lambda: Mul(x, x, evaluate=False).args_cnc(cset=True)) assert Mul(x, y, x, evaluate=False).args_cnc() == \ [[x, y, x], []] # always split -1 from leading number assert (-1.*x).args_cnc() == [[-1, 1.0, x], []] def test_new_rawargs(): n = Symbol('n', commutative=False) a = x + n assert a.is_commutative is False assert a._new_rawargs(x).is_commutative assert a._new_rawargs(x, y).is_commutative assert a._new_rawargs(x, n).is_commutative is False assert a._new_rawargs(x, y, n).is_commutative is False m = x*n assert m.is_commutative is False assert m._new_rawargs(x).is_commutative assert m._new_rawargs(n).is_commutative is False assert m._new_rawargs(x, y).is_commutative assert m._new_rawargs(x, n).is_commutative is False assert m._new_rawargs(x, y, n).is_commutative is False assert m._new_rawargs(x, n, reeval=False).is_commutative is False assert m._new_rawargs(S.One) is S.One def test_issue_5226(): assert Add(evaluate=False) == 0 assert Mul(evaluate=False) == 1 assert Mul(x + y, evaluate=False).is_Add def test_free_symbols(): # free_symbols should return the free symbols of an object assert S.One.free_symbols == set() assert x.free_symbols == {x} assert Integral(x, (x, 1, y)).free_symbols == {y} assert (-Integral(x, (x, 1, y))).free_symbols == {y} assert meter.free_symbols == set() assert (meter**x).free_symbols == {x} def test_issue_5300(): x = Symbol('x', commutative=False) assert x*sqrt(2)/sqrt(6) == x*sqrt(3)/3 def test_floordiv(): from sympy.functions.elementary.integers import floor assert x // y == floor(x / y) def test_as_coeff_Mul(): assert S.Zero.as_coeff_Mul() == (S.One, S.Zero) assert Integer(3).as_coeff_Mul() == (Integer(3), Integer(1)) assert Rational(3, 4).as_coeff_Mul() == (Rational(3, 4), Integer(1)) assert Float(5.0).as_coeff_Mul() == (Float(5.0), Integer(1)) assert (Integer(3)*x).as_coeff_Mul() == (Integer(3), x) assert (Rational(3, 4)*x).as_coeff_Mul() == (Rational(3, 4), x) assert (Float(5.0)*x).as_coeff_Mul() == (Float(5.0), x) assert (Integer(3)*x*y).as_coeff_Mul() == (Integer(3), x*y) assert (Rational(3, 4)*x*y).as_coeff_Mul() == (Rational(3, 4), x*y) assert (Float(5.0)*x*y).as_coeff_Mul() == (Float(5.0), x*y) assert (x).as_coeff_Mul() == (S.One, x) assert (x*y).as_coeff_Mul() == (S.One, x*y) assert (-oo*x).as_coeff_Mul(rational=True) == (-1, oo*x) def test_as_coeff_Add(): assert Integer(3).as_coeff_Add() == (Integer(3), Integer(0)) assert Rational(3, 4).as_coeff_Add() == (Rational(3, 4), Integer(0)) assert Float(5.0).as_coeff_Add() == (Float(5.0), Integer(0)) assert (Integer(3) + x).as_coeff_Add() == (Integer(3), x) assert (Rational(3, 4) + x).as_coeff_Add() == (Rational(3, 4), x) assert (Float(5.0) + x).as_coeff_Add() == (Float(5.0), x) assert (Float(5.0) + x).as_coeff_Add(rational=True) == (0, Float(5.0) + x) assert (Integer(3) + x + y).as_coeff_Add() == (Integer(3), x + y) assert (Rational(3, 4) + x + y).as_coeff_Add() == (Rational(3, 4), x + y) assert (Float(5.0) + x + y).as_coeff_Add() == (Float(5.0), x + y) assert (x).as_coeff_Add() == (S.Zero, x) assert (x*y).as_coeff_Add() == (S.Zero, x*y) def test_expr_sorting(): f, g = symbols('f,g', cls=Function) exprs = [1/x**2, 1/x, sqrt(sqrt(x)), sqrt(x), x, sqrt(x)**3, x**2] assert sorted(exprs, key=default_sort_key) == exprs exprs = [x, 2*x, 2*x**2, 2*x**3, x**n, 2*x**n, sin(x), sin(x)**n, sin(x**2), cos(x), cos(x**2), tan(x)] assert sorted(exprs, key=default_sort_key) == exprs exprs = [x + 1, x**2 + x + 1, x**3 + x**2 + x + 1] assert sorted(exprs, key=default_sort_key) == exprs exprs = [S(4), x - 3*I/2, x + 3*I/2, x - 4*I + 1, x + 4*I + 1] assert sorted(exprs, key=default_sort_key) == exprs exprs = [f(1), f(2), f(3), f(1, 2, 3), g(1), g(2), g(3), g(1, 2, 3)] assert sorted(exprs, key=default_sort_key) == exprs exprs = [f(x), g(x), exp(x), sin(x), cos(x), factorial(x)] assert sorted(exprs, key=default_sort_key) == exprs exprs = [Tuple(x, y), Tuple(x, z), Tuple(x, y, z)] assert sorted(exprs, key=default_sort_key) == exprs exprs = [[3], [1, 2]] assert sorted(exprs, key=default_sort_key) == exprs exprs = [[1, 2], [2, 3]] assert sorted(exprs, key=default_sort_key) == exprs exprs = [[1, 2], [1, 2, 3]] assert sorted(exprs, key=default_sort_key) == exprs exprs = [{x: -y}, {x: y}] assert sorted(exprs, key=default_sort_key) == exprs exprs = [{1}, {1, 2}] assert sorted(exprs, key=default_sort_key) == exprs a, b = exprs = [Dummy('x'), Dummy('x')] assert sorted([b, a], key=default_sort_key) == exprs def test_as_ordered_factors(): f, g = symbols('f,g', cls=Function) assert x.as_ordered_factors() == [x] assert (2*x*x**n*sin(x)*cos(x)).as_ordered_factors() \ == [Integer(2), x, x**n, sin(x), cos(x)] args = [f(1), f(2), f(3), f(1, 2, 3), g(1), g(2), g(3), g(1, 2, 3)] expr = Mul(*args) assert expr.as_ordered_factors() == args A, B = symbols('A,B', commutative=False) assert (A*B).as_ordered_factors() == [A, B] assert (B*A).as_ordered_factors() == [B, A] def test_as_ordered_terms(): f, g = symbols('f,g', cls=Function) assert x.as_ordered_terms() == [x] assert (sin(x)**2*cos(x) + sin(x)*cos(x)**2 + 1).as_ordered_terms() \ == [sin(x)**2*cos(x), sin(x)*cos(x)**2, 1] args = [f(1), f(2), f(3), f(1, 2, 3), g(1), g(2), g(3), g(1, 2, 3)] expr = Add(*args) assert expr.as_ordered_terms() == args assert (1 + 4*sqrt(3)*pi*x).as_ordered_terms() == [4*pi*x*sqrt(3), 1] assert ( 2 + 3*I).as_ordered_terms() == [2, 3*I] assert (-2 + 3*I).as_ordered_terms() == [-2, 3*I] assert ( 2 - 3*I).as_ordered_terms() == [2, -3*I] assert (-2 - 3*I).as_ordered_terms() == [-2, -3*I] assert ( 4 + 3*I).as_ordered_terms() == [4, 3*I] assert (-4 + 3*I).as_ordered_terms() == [-4, 3*I] assert ( 4 - 3*I).as_ordered_terms() == [4, -3*I] assert (-4 - 3*I).as_ordered_terms() == [-4, -3*I] f = x**2*y**2 + x*y**4 + y + 2 assert f.as_ordered_terms(order="lex") == [x**2*y**2, x*y**4, y, 2] assert f.as_ordered_terms(order="grlex") == [x*y**4, x**2*y**2, y, 2] assert f.as_ordered_terms(order="rev-lex") == [2, y, x*y**4, x**2*y**2] assert f.as_ordered_terms(order="rev-grlex") == [2, y, x**2*y**2, x*y**4] k = symbols('k') assert k.as_ordered_terms(data=True) == ([(k, ((1.0, 0.0), (1,), ()))], [k]) def test_sort_key_atomic_expr(): from sympy.physics.units import m, s assert sorted([-m, s], key=lambda arg: arg.sort_key()) == [-m, s] def test_eval_interval(): assert exp(x)._eval_interval(*Tuple(x, 0, 1)) == exp(1) - exp(0) # issue 4199 # first subs and limit gives NaN a = x/y assert a._eval_interval(x, S.Zero, oo)._eval_interval(y, oo, S.Zero) is S.NaN # second subs and limit gives NaN assert a._eval_interval(x, S.Zero, oo)._eval_interval(y, S.Zero, oo) is S.NaN # difference gives S.NaN a = x - y assert a._eval_interval(x, S.One, oo)._eval_interval(y, oo, S.One) is S.NaN raises(ValueError, lambda: x._eval_interval(x, None, None)) a = -y*Heaviside(x - y) assert a._eval_interval(x, -oo, oo) == -y assert a._eval_interval(x, oo, -oo) == y def test_eval_interval_zoo(): # Test that limit is used when zoo is returned assert Si(1/x)._eval_interval(x, S.Zero, S.One) == -pi/2 + Si(1) def test_primitive(): assert (3*(x + 1)**2).primitive() == (3, (x + 1)**2) assert (6*x + 2).primitive() == (2, 3*x + 1) assert (x/2 + 3).primitive() == (S.Half, x + 6) eq = (6*x + 2)*(x/2 + 3) assert eq.primitive()[0] == 1 eq = (2 + 2*x)**2 assert eq.primitive()[0] == 1 assert (4.0*x).primitive() == (1, 4.0*x) assert (4.0*x + y/2).primitive() == (S.Half, 8.0*x + y) assert (-2*x).primitive() == (2, -x) assert Add(5*z/7, 0.5*x, 3*y/2, evaluate=False).primitive() == \ (S.One/14, 7.0*x + 21*y + 10*z) for i in [S.Infinity, S.NegativeInfinity, S.ComplexInfinity]: assert (i + x/3).primitive() == \ (S.One/3, i + x) assert (S.Infinity + 2*x/3 + 4*y/7).primitive() == \ (S.One/21, 14*x + 12*y + oo) assert S.Zero.primitive() == (S.One, S.Zero) def test_issue_5843(): a = 1 + x assert (2*a).extract_multiplicatively(a) == 2 assert (4*a).extract_multiplicatively(2*a) == 2 assert ((3*a)*(2*a)).extract_multiplicatively(a) == 6*a def test_is_constant(): from sympy.solvers.solvers import checksol Sum(x, (x, 1, 10)).is_constant() is True Sum(x, (x, 1, n)).is_constant() is False Sum(x, (x, 1, n)).is_constant(y) is True Sum(x, (x, 1, n)).is_constant(n) is False Sum(x, (x, 1, n)).is_constant(x) is True eq = a*cos(x)**2 + a*sin(x)**2 - a eq.is_constant() is True assert eq.subs({x: pi, a: 2}) == eq.subs({x: pi, a: 3}) == 0 assert x.is_constant() is False assert x.is_constant(y) is True assert checksol(x, x, Sum(x, (x, 1, n))) is False assert checksol(x, x, Sum(x, (x, 1, n))) is False f = Function('f') assert f(1).is_constant assert checksol(x, x, f(x)) is False assert Pow(x, S.Zero, evaluate=False).is_constant() is True # == 1 assert Pow(S.Zero, x, evaluate=False).is_constant() is False # == 0 or 1 assert (2**x).is_constant() is False assert Pow(S(2), S(3), evaluate=False).is_constant() is True z1, z2 = symbols('z1 z2', zero=True) assert (z1 + 2*z2).is_constant() is True assert meter.is_constant() is True assert (3*meter).is_constant() is True assert (x*meter).is_constant() is False def test_equals(): assert (-3 - sqrt(5) + (-sqrt(10)/2 - sqrt(2)/2)**2).equals(0) assert (x**2 - 1).equals((x + 1)*(x - 1)) assert (cos(x)**2 + sin(x)**2).equals(1) assert (a*cos(x)**2 + a*sin(x)**2).equals(a) r = sqrt(2) assert (-1/(r + r*x) + 1/r/(1 + x)).equals(0) assert factorial(x + 1).equals((x + 1)*factorial(x)) assert sqrt(3).equals(2*sqrt(3)) is False assert (sqrt(5)*sqrt(3)).equals(sqrt(3)) is False assert (sqrt(5) + sqrt(3)).equals(0) is False assert (sqrt(5) + pi).equals(0) is False assert meter.equals(0) is False assert (3*meter**2).equals(0) is False eq = -(-1)**(S(3)/4)*6**(S.One/4) + (-6)**(S.One/4)*I if eq != 0: # if canonicalization makes this zero, skip the test assert eq.equals(0) assert sqrt(x).equals(0) is False # from integrate(x*sqrt(1 + 2*x), x); # diff is zero only when assumptions allow i = 2*sqrt(2)*x**(S(5)/2)*(1 + 1/(2*x))**(S(5)/2)/5 + \ 2*sqrt(2)*x**(S(3)/2)*(1 + 1/(2*x))**(S(5)/2)/(-6 - 3/x) ans = sqrt(2*x + 1)*(6*x**2 + x - 1)/15 diff = i - ans assert diff.equals(0) is False assert diff.subs(x, Rational(-1, 2)/2) == 7*sqrt(2)/120 # there are regions for x for which the expression is True, for # example, when x < -1/2 or x > 0 the expression is zero p = Symbol('p', positive=True) assert diff.subs(x, p).equals(0) is True assert diff.subs(x, -1).equals(0) is True # prove via minimal_polynomial or self-consistency eq = sqrt(1 + sqrt(3)) + sqrt(3 + 3*sqrt(3)) - sqrt(10 + 6*sqrt(3)) assert eq.equals(0) q = 3**Rational(1, 3) + 3 p = expand(q**3)**Rational(1, 3) assert (p - q).equals(0) # issue 6829 # eq = q*x + q/4 + x**4 + x**3 + 2*x**2 - S.One/3 # z = eq.subs(x, solve(eq, x)[0]) q = symbols('q') z = (q*(-sqrt(-2*(-(q - S(7)/8)**S(2)/8 - S(2197)/13824)**(S.One/3) - S(13)/12)/2 - sqrt((2*q - S(7)/4)/sqrt(-2*(-(q - S(7)/8)**S(2)/8 - S(2197)/13824)**(S.One/3) - S(13)/12) + 2*(-(q - S(7)/8)**S(2)/8 - S(2197)/13824)**(S.One/3) - S(13)/6)/2 - S.One/4) + q/4 + (-sqrt(-2*(-(q - S(7)/8)**S(2)/8 - S(2197)/13824)**(S.One/3) - S(13)/12)/2 - sqrt((2*q - S(7)/4)/sqrt(-2*(-(q - S(7)/8)**S(2)/8 - S(2197)/13824)**(S.One/3) - S(13)/12) + 2*(-(q - S(7)/8)**S(2)/8 - S(2197)/13824)**(S.One/3) - S(13)/6)/2 - S.One/4)**4 + (-sqrt(-2*(-(q - S(7)/8)**S(2)/8 - S(2197)/13824)**(S.One/3) - S(13)/12)/2 - sqrt((2*q - S(7)/4)/sqrt(-2*(-(q - S(7)/8)**S(2)/8 - S(2197)/13824)**(S.One/3) - S(13)/12) + 2*(-(q - S(7)/8)**S(2)/8 - S(2197)/13824)**(S.One/3) - S(13)/6)/2 - S.One/4)**3 + 2*(-sqrt(-2*(-(q - S(7)/8)**S(2)/8 - S(2197)/13824)**(S.One/3) - S(13)/12)/2 - sqrt((2*q - S(7)/4)/sqrt(-2*(-(q - S(7)/8)**S(2)/8 - S(2197)/13824)**(S.One/3) - S(13)/12) + 2*(-(q - S(7)/8)**S(2)/8 - S(2197)/13824)**(S.One/3) - S(13)/6)/2 - S.One/4)**2 - Rational(1, 3)) assert z.equals(0) def test_random(): from sympy import posify, lucas assert posify(x)[0]._random() is not None assert lucas(n)._random(2, -2, 0, -1, 1) is None # issue 8662 assert Piecewise((Max(x, y), z))._random() is None def test_round(): from sympy.abc import x assert str(Float('0.1249999').round(2)) == '0.12' d20 = 12345678901234567890 ans = S(d20).round(2) assert ans.is_Integer and ans == d20 ans = S(d20).round(-2) assert ans.is_Integer and ans == 12345678901234567900 assert str(S('1/7').round(4)) == '0.1429' assert str(S('.[12345]').round(4)) == '0.1235' assert str(S('.1349').round(2)) == '0.13' n = S(12345) ans = n.round() assert ans.is_Integer assert ans == n ans = n.round(1) assert ans.is_Integer assert ans == n ans = n.round(4) assert ans.is_Integer assert ans == n assert n.round(-1) == 12340 r = Float(str(n)).round(-4) assert r == 10000 assert n.round(-5) == 0 assert str((pi + sqrt(2)).round(2)) == '4.56' assert (10*(pi + sqrt(2))).round(-1) == 50 raises(TypeError, lambda: round(x + 2, 2)) assert str(S(2.3).round(1)) == '2.3' # rounding in SymPy (as in Decimal) should be # exact for the given precision; we check here # that when a 5 follows the last digit that # the rounded digit will be even. for i in range(-99, 100): # construct a decimal that ends in 5, e.g. 123 -> 0.1235 s = str(abs(i)) p = len(s) # we are going to round to the last digit of i n = '0.%s5' % s # put a 5 after i's digits j = p + 2 # 2 for '0.' if i < 0: # 1 for '-' j += 1 n = '-' + n v = str(Float(n).round(p))[:j] # pertinent digits if v.endswith('.'): continue # it ends with 0 which is even L = int(v[-1]) # last digit assert L % 2 == 0, (n, '->', v) assert (Float(.3, 3) + 2*pi).round() == 7 assert (Float(.3, 3) + 2*pi*100).round() == 629 assert (pi + 2*E*I).round() == 3 + 5*I # don't let request for extra precision give more than # what is known (in this case, only 3 digits) assert str((Float(.03, 3) + 2*pi/100).round(5)) == '0.0928' assert str((Float(.03, 3) + 2*pi/100).round(4)) == '0.0928' assert S.Zero.round() == 0 a = (Add(1, Float('1.' + '9'*27, ''), evaluate=0)) assert a.round(10) == Float('3.0000000000', '') assert a.round(25) == Float('3.0000000000000000000000000', '') assert a.round(26) == Float('3.00000000000000000000000000', '') assert a.round(27) == Float('2.999999999999999999999999999', '') assert a.round(30) == Float('2.999999999999999999999999999', '') raises(TypeError, lambda: x.round()) f = Function('f') raises(TypeError, lambda: f(1).round()) # exact magnitude of 10 assert str(S.One.round()) == '1' assert str(S(100).round()) == '100' # applied to real and imaginary portions assert (2*pi + E*I).round() == 6 + 3*I assert (2*pi + I/10).round() == 6 assert (pi/10 + 2*I).round() == 2*I # the lhs re and im parts are Float with dps of 2 # and those on the right have dps of 15 so they won't compare # equal unless we use string or compare components (which will # then coerce the floats to the same precision) or re-create # the floats assert str((pi/10 + E*I).round(2)) == '0.31 + 2.72*I' assert str((pi/10 + E*I).round(2).as_real_imag()) == '(0.31, 2.72)' assert str((pi/10 + E*I).round(2)) == '0.31 + 2.72*I' # issue 6914 assert (I**(I + 3)).round(3) == Float('-0.208', '')*I # issue 8720 assert S(-123.6).round() == -124 assert S(-1.5).round() == -2 assert S(-100.5).round() == -100 assert S(-1.5 - 10.5*I).round() == -2 - 10*I # issue 7961 assert str(S(0.006).round(2)) == '0.01' assert str(S(0.00106).round(4)) == '0.0011' # issue 8147 assert S.NaN.round() is S.NaN assert S.Infinity.round() is S.Infinity assert S.NegativeInfinity.round() is S.NegativeInfinity assert S.ComplexInfinity.round() is S.ComplexInfinity # check that types match for i in range(2): f = float(i) # 2 args assert all(type(round(i, p)) is int for p in (-1, 0, 1)) assert all(S(i).round(p).is_Integer for p in (-1, 0, 1)) assert all(type(round(f, p)) is float for p in (-1, 0, 1)) assert all(S(f).round(p).is_Float for p in (-1, 0, 1)) # 1 arg (p is None) assert type(round(i)) is int assert S(i).round().is_Integer assert type(round(f)) is int assert S(f).round().is_Integer def test_held_expression_UnevaluatedExpr(): x = symbols("x") he = UnevaluatedExpr(1/x) e1 = x*he assert isinstance(e1, Mul) assert e1.args == (x, he) assert e1.doit() == 1 assert UnevaluatedExpr(Derivative(x, x)).doit(deep=False ) == Derivative(x, x) assert UnevaluatedExpr(Derivative(x, x)).doit() == 1 xx = Mul(x, x, evaluate=False) assert xx != x**2 ue2 = UnevaluatedExpr(xx) assert isinstance(ue2, UnevaluatedExpr) assert ue2.args == (xx,) assert ue2.doit() == x**2 assert ue2.doit(deep=False) == xx x2 = UnevaluatedExpr(2)*2 assert type(x2) is Mul assert x2.args == (2, UnevaluatedExpr(2)) def test_round_exception_nostr(): # Don't use the string form of the expression in the round exception, as # it's too slow s = Symbol('bad') try: s.round() except TypeError as e: assert 'bad' not in str(e) else: # Did not raise raise AssertionError("Did not raise") def test_extract_branch_factor(): assert exp_polar(2.0*I*pi).extract_branch_factor() == (1, 1) def test_identity_removal(): assert Add.make_args(x + 0) == (x,) assert Mul.make_args(x*1) == (x,) def test_float_0(): assert Float(0.0) + 1 == Float(1.0) @XFAIL def test_float_0_fail(): assert Float(0.0)*x == Float(0.0) assert (x + Float(0.0)).is_Add def test_issue_6325(): ans = (b**2 + z**2 - (b*(a + b*t) + z*(c + t*z))**2/( (a + b*t)**2 + (c + t*z)**2))/sqrt((a + b*t)**2 + (c + t*z)**2) e = sqrt((a + b*t)**2 + (c + z*t)**2) assert diff(e, t, 2) == ans e.diff(t, 2) == ans assert diff(e, t, 2, simplify=False) != ans def test_issue_7426(): f1 = a % c f2 = x % z assert f1.equals(f2) is None def test_issue_11122(): x = Symbol('x', extended_positive=False) assert unchanged(Gt, x, 0) # (x > 0) # (x > 0) should remain unevaluated after PR #16956 x = Symbol('x', positive=False, real=True) assert (x > 0) is S.false def test_issue_10651(): x = Symbol('x', real=True) e1 = (-1 + x)/(1 - x) e3 = (4*x**2 - 4)/((1 - x)*(1 + x)) e4 = 1/(cos(x)**2) - (tan(x))**2 x = Symbol('x', positive=True) e5 = (1 + x)/x assert e1.is_constant() is None assert e3.is_constant() is None assert e4.is_constant() is None assert e5.is_constant() is False def test_issue_10161(): x = symbols('x', real=True) assert x*abs(x)*abs(x) == x**3 def test_issue_10755(): x = symbols('x') raises(TypeError, lambda: int(log(x))) raises(TypeError, lambda: log(x).round(2)) def test_issue_11877(): x = symbols('x') assert integrate(log(S.Half - x), (x, 0, S.Half)) == Rational(-1, 2) -log(2)/2 def test_normal(): x = symbols('x') e = Mul(S.Half, 1 + x, evaluate=False) assert e.normal() == e def test_expr(): x = symbols('x') raises(TypeError, lambda: tan(x).series(x, 2, oo, "+")) def test_ExprBuilder(): eb = ExprBuilder(Mul) eb.args.extend([x, x]) assert eb.build() == x**2 def test_non_string_equality(): # Expressions should not compare equal to strings x = symbols('x') one = sympify(1) assert (x == 'x') is False assert (x != 'x') is True assert (one == '1') is False assert (one != '1') is True assert (x + 1 == 'x + 1') is False assert (x + 1 != 'x + 1') is True # Make sure == doesn't try to convert the resulting expression to a string # (e.g., by calling sympify() instead of _sympify()) class BadRepr: def __repr__(self): raise RuntimeError assert (x == BadRepr()) is False assert (x != BadRepr()) is True def test_21494(): from sympy.testing.pytest import warns_deprecated_sympy with warns_deprecated_sympy(): assert x.expr_free_symbols == {x}
b044515a9f12f6482546295debc8564974df982f638626219964253b64cee267
"""Test whether all elements of cls.args are instances of Basic. """ # NOTE: keep tests sorted by (module, class name) key. If a class can't # be instantiated, add it here anyway with @SKIP("abstract class) (see # e.g. Function). import os import re from sympy import (Basic, S, symbols, sqrt, sin, oo, Interval, exp, Lambda, pi, Eq, log, Function, Rational, Q) from sympy.testing.pytest import XFAIL, SKIP a, b, c, x, y, z = symbols('a,b,c,x,y,z') whitelist = [ "sympy.assumptions.predicates", # tested by test_predicates() "sympy.assumptions.relation.equality", # tested by test_predicates() ] def test_all_classes_are_tested(): this = os.path.split(__file__)[0] path = os.path.join(this, os.pardir, os.pardir) sympy_path = os.path.abspath(path) prefix = os.path.split(sympy_path)[0] + os.sep re_cls = re.compile(r"^class ([A-Za-z][A-Za-z0-9_]*)\s*\(", re.MULTILINE) modules = {} for root, dirs, files in os.walk(sympy_path): module = root.replace(prefix, "").replace(os.sep, ".") for file in files: if file.startswith(("_", "test_", "bench_")): continue if not file.endswith(".py"): continue with open(os.path.join(root, file), encoding='utf-8') as f: text = f.read() submodule = module + '.' + file[:-3] if any(submodule.startswith(wpath) for wpath in whitelist): continue names = re_cls.findall(text) if not names: continue try: mod = __import__(submodule, fromlist=names) except ImportError: continue def is_Basic(name): cls = getattr(mod, name) if hasattr(cls, '_sympy_deprecated_func'): cls = cls._sympy_deprecated_func if not isinstance(cls, type): # check instance of singleton class with same name cls = type(cls) return issubclass(cls, Basic) names = list(filter(is_Basic, names)) if names: modules[submodule] = names ns = globals() failed = [] for module, names in modules.items(): mod = module.replace('.', '__') for name in names: test = 'test_' + mod + '__' + name if test not in ns: failed.append(module + '.' + name) assert not failed, "Missing classes: %s. Please add tests for these to sympy/core/tests/test_args.py." % ", ".join(failed) def _test_args(obj): all_basic = all(isinstance(arg, Basic) for arg in obj.args) # Ideally obj.func(*obj.args) would always recreate the object, but for # now, we only require it for objects with non-empty .args recreatable = not obj.args or obj.func(*obj.args) == obj return all_basic and recreatable def test_sympy__assumptions__assume__AppliedPredicate(): from sympy.assumptions.assume import AppliedPredicate, Predicate assert _test_args(AppliedPredicate(Predicate("test"), 2)) assert _test_args(Q.is_true(True)) @SKIP("abstract class") def test_sympy__assumptions__assume__Predicate(): pass def test_predicates(): predicates = [ getattr(Q, attr) for attr in Q.__class__.__dict__ if not attr.startswith('__')] for p in predicates: assert _test_args(p) def test_sympy__assumptions__assume__UndefinedPredicate(): from sympy.assumptions.assume import Predicate assert _test_args(Predicate("test")) @SKIP('abstract class') def test_sympy__assumptions__relation__binrel__BinaryRelation(): pass def test_sympy__assumptions__relation__binrel__AppliedBinaryRelation(): assert _test_args(Q.eq(1, 2)) def test_sympy__assumptions__wrapper__AssumptionsWrapper(): from sympy.assumptions.wrapper import AssumptionsWrapper assert _test_args(AssumptionsWrapper(x, Q.positive(x))) @SKIP("abstract Class") def test_sympy__codegen__ast__AssignmentBase(): from sympy.codegen.ast import AssignmentBase assert _test_args(AssignmentBase(x, 1)) @SKIP("abstract Class") def test_sympy__codegen__ast__AugmentedAssignment(): from sympy.codegen.ast import AugmentedAssignment assert _test_args(AugmentedAssignment(x, 1)) def test_sympy__codegen__ast__AddAugmentedAssignment(): from sympy.codegen.ast import AddAugmentedAssignment assert _test_args(AddAugmentedAssignment(x, 1)) def test_sympy__codegen__ast__SubAugmentedAssignment(): from sympy.codegen.ast import SubAugmentedAssignment assert _test_args(SubAugmentedAssignment(x, 1)) def test_sympy__codegen__ast__MulAugmentedAssignment(): from sympy.codegen.ast import MulAugmentedAssignment assert _test_args(MulAugmentedAssignment(x, 1)) def test_sympy__codegen__ast__DivAugmentedAssignment(): from sympy.codegen.ast import DivAugmentedAssignment assert _test_args(DivAugmentedAssignment(x, 1)) def test_sympy__codegen__ast__ModAugmentedAssignment(): from sympy.codegen.ast import ModAugmentedAssignment assert _test_args(ModAugmentedAssignment(x, 1)) def test_sympy__codegen__ast__CodeBlock(): from sympy.codegen.ast import CodeBlock, Assignment assert _test_args(CodeBlock(Assignment(x, 1), Assignment(y, 2))) def test_sympy__codegen__ast__For(): from sympy.codegen.ast import For, CodeBlock, AddAugmentedAssignment from sympy import Range assert _test_args(For(x, Range(10), CodeBlock(AddAugmentedAssignment(y, 1)))) def test_sympy__codegen__ast__Token(): from sympy.codegen.ast import Token assert _test_args(Token()) def test_sympy__codegen__ast__ContinueToken(): from sympy.codegen.ast import ContinueToken assert _test_args(ContinueToken()) def test_sympy__codegen__ast__BreakToken(): from sympy.codegen.ast import BreakToken assert _test_args(BreakToken()) def test_sympy__codegen__ast__NoneToken(): from sympy.codegen.ast import NoneToken assert _test_args(NoneToken()) def test_sympy__codegen__ast__String(): from sympy.codegen.ast import String assert _test_args(String('foobar')) def test_sympy__codegen__ast__QuotedString(): from sympy.codegen.ast import QuotedString assert _test_args(QuotedString('foobar')) def test_sympy__codegen__ast__Comment(): from sympy.codegen.ast import Comment assert _test_args(Comment('this is a comment')) def test_sympy__codegen__ast__Node(): from sympy.codegen.ast import Node assert _test_args(Node()) assert _test_args(Node(attrs={1, 2, 3})) def test_sympy__codegen__ast__Type(): from sympy.codegen.ast import Type assert _test_args(Type('float128')) def test_sympy__codegen__ast__IntBaseType(): from sympy.codegen.ast import IntBaseType assert _test_args(IntBaseType('bigint')) def test_sympy__codegen__ast___SizedIntType(): from sympy.codegen.ast import _SizedIntType assert _test_args(_SizedIntType('int128', 128)) def test_sympy__codegen__ast__SignedIntType(): from sympy.codegen.ast import SignedIntType assert _test_args(SignedIntType('int128_with_sign', 128)) def test_sympy__codegen__ast__UnsignedIntType(): from sympy.codegen.ast import UnsignedIntType assert _test_args(UnsignedIntType('unt128', 128)) def test_sympy__codegen__ast__FloatBaseType(): from sympy.codegen.ast import FloatBaseType assert _test_args(FloatBaseType('positive_real')) def test_sympy__codegen__ast__FloatType(): from sympy.codegen.ast import FloatType assert _test_args(FloatType('float242', 242, nmant=142, nexp=99)) def test_sympy__codegen__ast__ComplexBaseType(): from sympy.codegen.ast import ComplexBaseType assert _test_args(ComplexBaseType('positive_cmplx')) def test_sympy__codegen__ast__ComplexType(): from sympy.codegen.ast import ComplexType assert _test_args(ComplexType('complex42', 42, nmant=15, nexp=5)) def test_sympy__codegen__ast__Attribute(): from sympy.codegen.ast import Attribute assert _test_args(Attribute('noexcept')) def test_sympy__codegen__ast__Variable(): from sympy.codegen.ast import Variable, Type, value_const assert _test_args(Variable(x)) assert _test_args(Variable(y, Type('float32'), {value_const})) assert _test_args(Variable(z, type=Type('float64'))) def test_sympy__codegen__ast__Pointer(): from sympy.codegen.ast import Pointer, Type, pointer_const assert _test_args(Pointer(x)) assert _test_args(Pointer(y, type=Type('float32'))) assert _test_args(Pointer(z, Type('float64'), {pointer_const})) def test_sympy__codegen__ast__Declaration(): from sympy.codegen.ast import Declaration, Variable, Type vx = Variable(x, type=Type('float')) assert _test_args(Declaration(vx)) def test_sympy__codegen__ast__While(): from sympy.codegen.ast import While, AddAugmentedAssignment assert _test_args(While(abs(x) < 1, [AddAugmentedAssignment(x, -1)])) def test_sympy__codegen__ast__Scope(): from sympy.codegen.ast import Scope, AddAugmentedAssignment assert _test_args(Scope([AddAugmentedAssignment(x, -1)])) def test_sympy__codegen__ast__Stream(): from sympy.codegen.ast import Stream assert _test_args(Stream('stdin')) def test_sympy__codegen__ast__Print(): from sympy.codegen.ast import Print assert _test_args(Print([x, y])) assert _test_args(Print([x, y], "%d %d")) def test_sympy__codegen__ast__FunctionPrototype(): from sympy.codegen.ast import FunctionPrototype, real, Declaration, Variable inp_x = Declaration(Variable(x, type=real)) assert _test_args(FunctionPrototype(real, 'pwer', [inp_x])) def test_sympy__codegen__ast__FunctionDefinition(): from sympy.codegen.ast import FunctionDefinition, real, Declaration, Variable, Assignment inp_x = Declaration(Variable(x, type=real)) assert _test_args(FunctionDefinition(real, 'pwer', [inp_x], [Assignment(x, x**2)])) def test_sympy__codegen__ast__Return(): from sympy.codegen.ast import Return assert _test_args(Return(x)) def test_sympy__codegen__ast__FunctionCall(): from sympy.codegen.ast import FunctionCall assert _test_args(FunctionCall('pwer', [x])) def test_sympy__codegen__ast__Element(): from sympy.codegen.ast import Element assert _test_args(Element('x', range(3))) def test_sympy__codegen__cnodes__CommaOperator(): from sympy.codegen.cnodes import CommaOperator assert _test_args(CommaOperator(1, 2)) def test_sympy__codegen__cnodes__goto(): from sympy.codegen.cnodes import goto assert _test_args(goto('early_exit')) def test_sympy__codegen__cnodes__Label(): from sympy.codegen.cnodes import Label assert _test_args(Label('early_exit')) def test_sympy__codegen__cnodes__PreDecrement(): from sympy.codegen.cnodes import PreDecrement assert _test_args(PreDecrement(x)) def test_sympy__codegen__cnodes__PostDecrement(): from sympy.codegen.cnodes import PostDecrement assert _test_args(PostDecrement(x)) def test_sympy__codegen__cnodes__PreIncrement(): from sympy.codegen.cnodes import PreIncrement assert _test_args(PreIncrement(x)) def test_sympy__codegen__cnodes__PostIncrement(): from sympy.codegen.cnodes import PostIncrement assert _test_args(PostIncrement(x)) def test_sympy__codegen__cnodes__struct(): from sympy.codegen.ast import real, Variable from sympy.codegen.cnodes import struct assert _test_args(struct(declarations=[ Variable(x, type=real), Variable(y, type=real) ])) def test_sympy__codegen__cnodes__union(): from sympy.codegen.ast import float32, int32, Variable from sympy.codegen.cnodes import union assert _test_args(union(declarations=[ Variable(x, type=float32), Variable(y, type=int32) ])) def test_sympy__codegen__cxxnodes__using(): from sympy.codegen.cxxnodes import using assert _test_args(using('std::vector')) assert _test_args(using('std::vector', 'vec')) def test_sympy__codegen__fnodes__Program(): from sympy.codegen.fnodes import Program assert _test_args(Program('foobar', [])) def test_sympy__codegen__fnodes__Module(): from sympy.codegen.fnodes import Module assert _test_args(Module('foobar', [], [])) def test_sympy__codegen__fnodes__Subroutine(): from sympy.codegen.fnodes import Subroutine x = symbols('x', real=True) assert _test_args(Subroutine('foo', [x], [])) def test_sympy__codegen__fnodes__GoTo(): from sympy.codegen.fnodes import GoTo assert _test_args(GoTo([10])) assert _test_args(GoTo([10, 20], x > 1)) def test_sympy__codegen__fnodes__FortranReturn(): from sympy.codegen.fnodes import FortranReturn assert _test_args(FortranReturn(10)) def test_sympy__codegen__fnodes__Extent(): from sympy.codegen.fnodes import Extent assert _test_args(Extent()) assert _test_args(Extent(None)) assert _test_args(Extent(':')) assert _test_args(Extent(-3, 4)) assert _test_args(Extent(x, y)) def test_sympy__codegen__fnodes__use_rename(): from sympy.codegen.fnodes import use_rename assert _test_args(use_rename('loc', 'glob')) def test_sympy__codegen__fnodes__use(): from sympy.codegen.fnodes import use assert _test_args(use('modfoo', only='bar')) def test_sympy__codegen__fnodes__SubroutineCall(): from sympy.codegen.fnodes import SubroutineCall assert _test_args(SubroutineCall('foo', ['bar', 'baz'])) def test_sympy__codegen__fnodes__Do(): from sympy.codegen.fnodes import Do assert _test_args(Do([], 'i', 1, 42)) def test_sympy__codegen__fnodes__ImpliedDoLoop(): from sympy.codegen.fnodes import ImpliedDoLoop assert _test_args(ImpliedDoLoop('i', 'i', 1, 42)) def test_sympy__codegen__fnodes__ArrayConstructor(): from sympy.codegen.fnodes import ArrayConstructor assert _test_args(ArrayConstructor([1, 2, 3])) from sympy.codegen.fnodes import ImpliedDoLoop idl = ImpliedDoLoop('i', 'i', 1, 42) assert _test_args(ArrayConstructor([1, idl, 3])) def test_sympy__codegen__fnodes__sum_(): from sympy.codegen.fnodes import sum_ assert _test_args(sum_('arr')) def test_sympy__codegen__fnodes__product_(): from sympy.codegen.fnodes import product_ assert _test_args(product_('arr')) def test_sympy__codegen__numpy_nodes__logaddexp(): from sympy.codegen.numpy_nodes import logaddexp assert _test_args(logaddexp(x, y)) def test_sympy__codegen__numpy_nodes__logaddexp2(): from sympy.codegen.numpy_nodes import logaddexp2 assert _test_args(logaddexp2(x, y)) def test_sympy__codegen__scipy_nodes__cosm1(): from sympy.codegen.scipy_nodes import cosm1 assert _test_args(cosm1(x)) @XFAIL def test_sympy__combinatorics__graycode__GrayCode(): from sympy.combinatorics.graycode import GrayCode # an integer is given and returned from GrayCode as the arg assert _test_args(GrayCode(3, start='100')) assert _test_args(GrayCode(3, rank=1)) def test_sympy__combinatorics__subsets__Subset(): from sympy.combinatorics.subsets import Subset assert _test_args(Subset([0, 1], [0, 1, 2, 3])) assert _test_args(Subset(['c', 'd'], ['a', 'b', 'c', 'd'])) def test_sympy__combinatorics__permutations__Permutation(): from sympy.combinatorics.permutations import Permutation assert _test_args(Permutation([0, 1, 2, 3])) def test_sympy__combinatorics__permutations__AppliedPermutation(): from sympy.combinatorics.permutations import Permutation from sympy.combinatorics.permutations import AppliedPermutation p = Permutation([0, 1, 2, 3]) assert _test_args(AppliedPermutation(p, 1)) def test_sympy__combinatorics__perm_groups__PermutationGroup(): from sympy.combinatorics.permutations import Permutation from sympy.combinatorics.perm_groups import PermutationGroup assert _test_args(PermutationGroup([Permutation([0, 1])])) def test_sympy__combinatorics__polyhedron__Polyhedron(): from sympy.combinatorics.permutations import Permutation from sympy.combinatorics.polyhedron import Polyhedron from sympy.abc import w, x, y, z pgroup = [Permutation([[0, 1, 2], [3]]), Permutation([[0, 1, 3], [2]]), Permutation([[0, 2, 3], [1]]), Permutation([[1, 2, 3], [0]]), Permutation([[0, 1], [2, 3]]), Permutation([[0, 2], [1, 3]]), Permutation([[0, 3], [1, 2]]), Permutation([[0, 1, 2, 3]])] corners = [w, x, y, z] faces = [(w, x, y), (w, y, z), (w, z, x), (x, y, z)] assert _test_args(Polyhedron(corners, faces, pgroup)) @XFAIL def test_sympy__combinatorics__prufer__Prufer(): from sympy.combinatorics.prufer import Prufer assert _test_args(Prufer([[0, 1], [0, 2], [0, 3]], 4)) def test_sympy__combinatorics__partitions__Partition(): from sympy.combinatorics.partitions import Partition assert _test_args(Partition([1])) @XFAIL def test_sympy__combinatorics__partitions__IntegerPartition(): from sympy.combinatorics.partitions import IntegerPartition assert _test_args(IntegerPartition([1])) def test_sympy__concrete__products__Product(): from sympy.concrete.products import Product assert _test_args(Product(x, (x, 0, 10))) assert _test_args(Product(x, (x, 0, y), (y, 0, 10))) @SKIP("abstract Class") def test_sympy__concrete__expr_with_limits__ExprWithLimits(): from sympy.concrete.expr_with_limits import ExprWithLimits assert _test_args(ExprWithLimits(x, (x, 0, 10))) assert _test_args(ExprWithLimits(x*y, (x, 0, 10.),(y,1.,3))) @SKIP("abstract Class") def test_sympy__concrete__expr_with_limits__AddWithLimits(): from sympy.concrete.expr_with_limits import AddWithLimits assert _test_args(AddWithLimits(x, (x, 0, 10))) assert _test_args(AddWithLimits(x*y, (x, 0, 10),(y,1,3))) @SKIP("abstract Class") def test_sympy__concrete__expr_with_intlimits__ExprWithIntLimits(): from sympy.concrete.expr_with_intlimits import ExprWithIntLimits assert _test_args(ExprWithIntLimits(x, (x, 0, 10))) assert _test_args(ExprWithIntLimits(x*y, (x, 0, 10),(y,1,3))) def test_sympy__concrete__summations__Sum(): from sympy.concrete.summations import Sum assert _test_args(Sum(x, (x, 0, 10))) assert _test_args(Sum(x, (x, 0, y), (y, 0, 10))) def test_sympy__core__add__Add(): from sympy.core.add import Add assert _test_args(Add(x, y, z, 2)) def test_sympy__core__basic__Atom(): from sympy.core.basic import Atom assert _test_args(Atom()) def test_sympy__core__basic__Basic(): from sympy.core.basic import Basic assert _test_args(Basic()) def test_sympy__core__containers__Dict(): from sympy.core.containers import Dict assert _test_args(Dict({x: y, y: z})) def test_sympy__core__containers__Tuple(): from sympy.core.containers import Tuple assert _test_args(Tuple(x, y, z, 2)) def test_sympy__core__expr__AtomicExpr(): from sympy.core.expr import AtomicExpr assert _test_args(AtomicExpr()) def test_sympy__core__expr__Expr(): from sympy.core.expr import Expr assert _test_args(Expr()) def test_sympy__core__expr__UnevaluatedExpr(): from sympy.core.expr import UnevaluatedExpr from sympy.abc import x assert _test_args(UnevaluatedExpr(x)) def test_sympy__core__function__Application(): from sympy.core.function import Application assert _test_args(Application(1, 2, 3)) def test_sympy__core__function__AppliedUndef(): from sympy.core.function import AppliedUndef assert _test_args(AppliedUndef(1, 2, 3)) def test_sympy__core__function__Derivative(): from sympy.core.function import Derivative assert _test_args(Derivative(2, x, y, 3)) @SKIP("abstract class") def test_sympy__core__function__Function(): pass def test_sympy__core__function__Lambda(): assert _test_args(Lambda((x, y), x + y + z)) def test_sympy__core__function__Subs(): from sympy.core.function import Subs assert _test_args(Subs(x + y, x, 2)) def test_sympy__core__function__WildFunction(): from sympy.core.function import WildFunction assert _test_args(WildFunction('f')) def test_sympy__core__mod__Mod(): from sympy.core.mod import Mod assert _test_args(Mod(x, 2)) def test_sympy__core__mul__Mul(): from sympy.core.mul import Mul assert _test_args(Mul(2, x, y, z)) def test_sympy__core__numbers__Catalan(): from sympy.core.numbers import Catalan assert _test_args(Catalan()) def test_sympy__core__numbers__ComplexInfinity(): from sympy.core.numbers import ComplexInfinity assert _test_args(ComplexInfinity()) def test_sympy__core__numbers__EulerGamma(): from sympy.core.numbers import EulerGamma assert _test_args(EulerGamma()) def test_sympy__core__numbers__Exp1(): from sympy.core.numbers import Exp1 assert _test_args(Exp1()) def test_sympy__core__numbers__Float(): from sympy.core.numbers import Float assert _test_args(Float(1.23)) def test_sympy__core__numbers__GoldenRatio(): from sympy.core.numbers import GoldenRatio assert _test_args(GoldenRatio()) def test_sympy__core__numbers__TribonacciConstant(): from sympy.core.numbers import TribonacciConstant assert _test_args(TribonacciConstant()) def test_sympy__core__numbers__Half(): from sympy.core.numbers import Half assert _test_args(Half()) def test_sympy__core__numbers__ImaginaryUnit(): from sympy.core.numbers import ImaginaryUnit assert _test_args(ImaginaryUnit()) def test_sympy__core__numbers__Infinity(): from sympy.core.numbers import Infinity assert _test_args(Infinity()) def test_sympy__core__numbers__Integer(): from sympy.core.numbers import Integer assert _test_args(Integer(7)) @SKIP("abstract class") def test_sympy__core__numbers__IntegerConstant(): pass def test_sympy__core__numbers__NaN(): from sympy.core.numbers import NaN assert _test_args(NaN()) def test_sympy__core__numbers__NegativeInfinity(): from sympy.core.numbers import NegativeInfinity assert _test_args(NegativeInfinity()) def test_sympy__core__numbers__NegativeOne(): from sympy.core.numbers import NegativeOne assert _test_args(NegativeOne()) def test_sympy__core__numbers__Number(): from sympy.core.numbers import Number assert _test_args(Number(1, 7)) def test_sympy__core__numbers__NumberSymbol(): from sympy.core.numbers import NumberSymbol assert _test_args(NumberSymbol()) def test_sympy__core__numbers__One(): from sympy.core.numbers import One assert _test_args(One()) def test_sympy__core__numbers__Pi(): from sympy.core.numbers import Pi assert _test_args(Pi()) def test_sympy__core__numbers__Rational(): from sympy.core.numbers import Rational assert _test_args(Rational(1, 7)) @SKIP("abstract class") def test_sympy__core__numbers__RationalConstant(): pass def test_sympy__core__numbers__Zero(): from sympy.core.numbers import Zero assert _test_args(Zero()) @SKIP("abstract class") def test_sympy__core__operations__AssocOp(): pass @SKIP("abstract class") def test_sympy__core__operations__LatticeOp(): pass def test_sympy__core__power__Pow(): from sympy.core.power import Pow assert _test_args(Pow(x, 2)) def test_sympy__algebras__quaternion__Quaternion(): from sympy.algebras.quaternion import Quaternion assert _test_args(Quaternion(x, 1, 2, 3)) def test_sympy__core__relational__Equality(): from sympy.core.relational import Equality assert _test_args(Equality(x, 2)) def test_sympy__core__relational__GreaterThan(): from sympy.core.relational import GreaterThan assert _test_args(GreaterThan(x, 2)) def test_sympy__core__relational__LessThan(): from sympy.core.relational import LessThan assert _test_args(LessThan(x, 2)) @SKIP("abstract class") def test_sympy__core__relational__Relational(): pass def test_sympy__core__relational__StrictGreaterThan(): from sympy.core.relational import StrictGreaterThan assert _test_args(StrictGreaterThan(x, 2)) def test_sympy__core__relational__StrictLessThan(): from sympy.core.relational import StrictLessThan assert _test_args(StrictLessThan(x, 2)) def test_sympy__core__relational__Unequality(): from sympy.core.relational import Unequality assert _test_args(Unequality(x, 2)) def test_sympy__sandbox__indexed_integrals__IndexedIntegral(): from sympy.tensor import IndexedBase, Idx from sympy.sandbox.indexed_integrals import IndexedIntegral A = IndexedBase('A') i, j = symbols('i j', integer=True) a1, a2 = symbols('a1:3', cls=Idx) assert _test_args(IndexedIntegral(A[a1], A[a2])) assert _test_args(IndexedIntegral(A[i], A[j])) def test_sympy__calculus__util__AccumulationBounds(): from sympy.calculus.util import AccumulationBounds assert _test_args(AccumulationBounds(0, 1)) def test_sympy__sets__ordinals__OmegaPower(): from sympy.sets.ordinals import OmegaPower assert _test_args(OmegaPower(1, 1)) def test_sympy__sets__ordinals__Ordinal(): from sympy.sets.ordinals import Ordinal, OmegaPower assert _test_args(Ordinal(OmegaPower(2, 1))) def test_sympy__sets__ordinals__OrdinalOmega(): from sympy.sets.ordinals import OrdinalOmega assert _test_args(OrdinalOmega()) def test_sympy__sets__ordinals__OrdinalZero(): from sympy.sets.ordinals import OrdinalZero assert _test_args(OrdinalZero()) def test_sympy__sets__powerset__PowerSet(): from sympy.sets.powerset import PowerSet from sympy.core.singleton import S assert _test_args(PowerSet(S.EmptySet)) def test_sympy__sets__sets__EmptySet(): from sympy.sets.sets import EmptySet assert _test_args(EmptySet()) def test_sympy__sets__sets__UniversalSet(): from sympy.sets.sets import UniversalSet assert _test_args(UniversalSet()) def test_sympy__sets__sets__FiniteSet(): from sympy.sets.sets import FiniteSet assert _test_args(FiniteSet(x, y, z)) def test_sympy__sets__sets__Interval(): from sympy.sets.sets import Interval assert _test_args(Interval(0, 1)) def test_sympy__sets__sets__ProductSet(): from sympy.sets.sets import ProductSet, Interval assert _test_args(ProductSet(Interval(0, 1), Interval(0, 1))) @SKIP("does it make sense to test this?") def test_sympy__sets__sets__Set(): from sympy.sets.sets import Set assert _test_args(Set()) def test_sympy__sets__sets__Intersection(): from sympy.sets.sets import Intersection, Interval from sympy.core.symbol import Symbol x = Symbol('x') y = Symbol('y') S = Intersection(Interval(0, x), Interval(y, 1)) assert isinstance(S, Intersection) assert _test_args(S) def test_sympy__sets__sets__Union(): from sympy.sets.sets import Union, Interval assert _test_args(Union(Interval(0, 1), Interval(2, 3))) def test_sympy__sets__sets__Complement(): from sympy.sets.sets import Complement assert _test_args(Complement(Interval(0, 2), Interval(0, 1))) def test_sympy__sets__sets__SymmetricDifference(): from sympy.sets.sets import FiniteSet, SymmetricDifference assert _test_args(SymmetricDifference(FiniteSet(1, 2, 3), \ FiniteSet(2, 3, 4))) def test_sympy__sets__sets__DisjointUnion(): from sympy.sets.sets import FiniteSet, DisjointUnion assert _test_args(DisjointUnion(FiniteSet(1, 2, 3), \ FiniteSet(2, 3, 4))) def test_sympy__core__trace__Tr(): from sympy.core.trace import Tr a, b = symbols('a b') assert _test_args(Tr(a + b)) def test_sympy__sets__setexpr__SetExpr(): from sympy.sets.setexpr import SetExpr assert _test_args(SetExpr(Interval(0, 1))) def test_sympy__sets__fancysets__Rationals(): from sympy.sets.fancysets import Rationals assert _test_args(Rationals()) def test_sympy__sets__fancysets__Naturals(): from sympy.sets.fancysets import Naturals assert _test_args(Naturals()) def test_sympy__sets__fancysets__Naturals0(): from sympy.sets.fancysets import Naturals0 assert _test_args(Naturals0()) def test_sympy__sets__fancysets__Integers(): from sympy.sets.fancysets import Integers assert _test_args(Integers()) def test_sympy__sets__fancysets__Reals(): from sympy.sets.fancysets import Reals assert _test_args(Reals()) def test_sympy__sets__fancysets__Complexes(): from sympy.sets.fancysets import Complexes assert _test_args(Complexes()) def test_sympy__sets__fancysets__ComplexRegion(): from sympy.sets.fancysets import ComplexRegion from sympy import S from sympy.sets import Interval a = Interval(0, 1) b = Interval(2, 3) theta = Interval(0, 2*S.Pi) assert _test_args(ComplexRegion(a*b)) assert _test_args(ComplexRegion(a*theta, polar=True)) def test_sympy__sets__fancysets__CartesianComplexRegion(): from sympy.sets.fancysets import CartesianComplexRegion from sympy.sets import Interval a = Interval(0, 1) b = Interval(2, 3) assert _test_args(CartesianComplexRegion(a*b)) def test_sympy__sets__fancysets__PolarComplexRegion(): from sympy.sets.fancysets import PolarComplexRegion from sympy import S from sympy.sets import Interval a = Interval(0, 1) theta = Interval(0, 2*S.Pi) assert _test_args(PolarComplexRegion(a*theta)) def test_sympy__sets__fancysets__ImageSet(): from sympy.sets.fancysets import ImageSet from sympy import S, Symbol x = Symbol('x') assert _test_args(ImageSet(Lambda(x, x**2), S.Naturals)) def test_sympy__sets__fancysets__Range(): from sympy.sets.fancysets import Range assert _test_args(Range(1, 5, 1)) def test_sympy__sets__conditionset__ConditionSet(): from sympy.sets.conditionset import ConditionSet from sympy import S, Symbol x = Symbol('x') assert _test_args(ConditionSet(x, Eq(x**2, 1), S.Reals)) def test_sympy__sets__contains__Contains(): from sympy.sets.fancysets import Range from sympy.sets.contains import Contains assert _test_args(Contains(x, Range(0, 10, 2))) # STATS from sympy.stats.crv_types import NormalDistribution nd = NormalDistribution(0, 1) from sympy.stats.frv_types import DieDistribution die = DieDistribution(6) def test_sympy__stats__crv__ContinuousDomain(): from sympy.stats.crv import ContinuousDomain assert _test_args(ContinuousDomain({x}, Interval(-oo, oo))) def test_sympy__stats__crv__SingleContinuousDomain(): from sympy.stats.crv import SingleContinuousDomain assert _test_args(SingleContinuousDomain(x, Interval(-oo, oo))) def test_sympy__stats__crv__ProductContinuousDomain(): from sympy.stats.crv import SingleContinuousDomain, ProductContinuousDomain D = SingleContinuousDomain(x, Interval(-oo, oo)) E = SingleContinuousDomain(y, Interval(0, oo)) assert _test_args(ProductContinuousDomain(D, E)) def test_sympy__stats__crv__ConditionalContinuousDomain(): from sympy.stats.crv import (SingleContinuousDomain, ConditionalContinuousDomain) D = SingleContinuousDomain(x, Interval(-oo, oo)) assert _test_args(ConditionalContinuousDomain(D, x > 0)) def test_sympy__stats__crv__ContinuousPSpace(): from sympy.stats.crv import ContinuousPSpace, SingleContinuousDomain D = SingleContinuousDomain(x, Interval(-oo, oo)) assert _test_args(ContinuousPSpace(D, nd)) def test_sympy__stats__crv__SingleContinuousPSpace(): from sympy.stats.crv import SingleContinuousPSpace assert _test_args(SingleContinuousPSpace(x, nd)) @SKIP("abstract class") def test_sympy__stats__rv__Distribution(): pass @SKIP("abstract class") def test_sympy__stats__crv__SingleContinuousDistribution(): pass def test_sympy__stats__drv__SingleDiscreteDomain(): from sympy.stats.drv import SingleDiscreteDomain assert _test_args(SingleDiscreteDomain(x, S.Naturals)) def test_sympy__stats__drv__ProductDiscreteDomain(): from sympy.stats.drv import SingleDiscreteDomain, ProductDiscreteDomain X = SingleDiscreteDomain(x, S.Naturals) Y = SingleDiscreteDomain(y, S.Integers) assert _test_args(ProductDiscreteDomain(X, Y)) def test_sympy__stats__drv__SingleDiscretePSpace(): from sympy.stats.drv import SingleDiscretePSpace from sympy.stats.drv_types import PoissonDistribution assert _test_args(SingleDiscretePSpace(x, PoissonDistribution(1))) def test_sympy__stats__drv__DiscretePSpace(): from sympy.stats.drv import DiscretePSpace, SingleDiscreteDomain density = Lambda(x, 2**(-x)) domain = SingleDiscreteDomain(x, S.Naturals) assert _test_args(DiscretePSpace(domain, density)) def test_sympy__stats__drv__ConditionalDiscreteDomain(): from sympy.stats.drv import ConditionalDiscreteDomain, SingleDiscreteDomain X = SingleDiscreteDomain(x, S.Naturals0) assert _test_args(ConditionalDiscreteDomain(X, x > 2)) def test_sympy__stats__joint_rv__JointPSpace(): from sympy.stats.joint_rv import JointPSpace, JointDistribution assert _test_args(JointPSpace('X', JointDistribution(1))) def test_sympy__stats__joint_rv__JointRandomSymbol(): from sympy.stats.joint_rv import JointRandomSymbol assert _test_args(JointRandomSymbol(x)) def test_sympy__stats__joint_rv_types__JointDistributionHandmade(): from sympy import Indexed from sympy.stats.joint_rv_types import JointDistributionHandmade x1, x2 = (Indexed('x', i) for i in (1, 2)) assert _test_args(JointDistributionHandmade(x1 + x2, S.Reals**2)) def test_sympy__stats__joint_rv__MarginalDistribution(): from sympy.stats.rv import RandomSymbol from sympy.stats.joint_rv import MarginalDistribution r = RandomSymbol(S('r')) assert _test_args(MarginalDistribution(r, (r,))) def test_sympy__stats__compound_rv__CompoundDistribution(): from sympy.stats.compound_rv import CompoundDistribution from sympy.stats.drv_types import PoissonDistribution, Poisson r = Poisson('r', 10) assert _test_args(CompoundDistribution(PoissonDistribution(r))) def test_sympy__stats__compound_rv__CompoundPSpace(): from sympy.stats.compound_rv import CompoundPSpace, CompoundDistribution from sympy.stats.drv_types import PoissonDistribution, Poisson r = Poisson('r', 5) C = CompoundDistribution(PoissonDistribution(r)) assert _test_args(CompoundPSpace('C', C)) @SKIP("abstract class") def test_sympy__stats__drv__SingleDiscreteDistribution(): pass @SKIP("abstract class") def test_sympy__stats__drv__DiscreteDistribution(): pass @SKIP("abstract class") def test_sympy__stats__drv__DiscreteDomain(): pass def test_sympy__stats__rv__RandomDomain(): from sympy.stats.rv import RandomDomain from sympy.sets.sets import FiniteSet assert _test_args(RandomDomain(FiniteSet(x), FiniteSet(1, 2, 3))) def test_sympy__stats__rv__SingleDomain(): from sympy.stats.rv import SingleDomain from sympy.sets.sets import FiniteSet assert _test_args(SingleDomain(x, FiniteSet(1, 2, 3))) def test_sympy__stats__rv__ConditionalDomain(): from sympy.stats.rv import ConditionalDomain, RandomDomain from sympy.sets.sets import FiniteSet D = RandomDomain(FiniteSet(x), FiniteSet(1, 2)) assert _test_args(ConditionalDomain(D, x > 1)) def test_sympy__stats__rv__MatrixDomain(): from sympy.stats.rv import MatrixDomain from sympy.matrices import MatrixSet from sympy import S assert _test_args(MatrixDomain(x, MatrixSet(2, 2, S.Reals))) def test_sympy__stats__rv__PSpace(): from sympy.stats.rv import PSpace, RandomDomain from sympy import FiniteSet D = RandomDomain(FiniteSet(x), FiniteSet(1, 2, 3, 4, 5, 6)) assert _test_args(PSpace(D, die)) @SKIP("abstract Class") def test_sympy__stats__rv__SinglePSpace(): pass def test_sympy__stats__rv__RandomSymbol(): from sympy.stats.rv import RandomSymbol from sympy.stats.crv import SingleContinuousPSpace A = SingleContinuousPSpace(x, nd) assert _test_args(RandomSymbol(x, A)) @SKIP("abstract Class") def test_sympy__stats__rv__ProductPSpace(): pass def test_sympy__stats__rv__IndependentProductPSpace(): from sympy.stats.rv import IndependentProductPSpace from sympy.stats.crv import SingleContinuousPSpace A = SingleContinuousPSpace(x, nd) B = SingleContinuousPSpace(y, nd) assert _test_args(IndependentProductPSpace(A, B)) def test_sympy__stats__rv__ProductDomain(): from sympy.stats.rv import ProductDomain, SingleDomain D = SingleDomain(x, Interval(-oo, oo)) E = SingleDomain(y, Interval(0, oo)) assert _test_args(ProductDomain(D, E)) def test_sympy__stats__symbolic_probability__Probability(): from sympy.stats.symbolic_probability import Probability from sympy.stats import Normal X = Normal('X', 0, 1) assert _test_args(Probability(X > 0)) def test_sympy__stats__symbolic_probability__Expectation(): from sympy.stats.symbolic_probability import Expectation from sympy.stats import Normal X = Normal('X', 0, 1) assert _test_args(Expectation(X > 0)) def test_sympy__stats__symbolic_probability__Covariance(): from sympy.stats.symbolic_probability import Covariance from sympy.stats import Normal X = Normal('X', 0, 1) Y = Normal('Y', 0, 3) assert _test_args(Covariance(X, Y)) def test_sympy__stats__symbolic_probability__Variance(): from sympy.stats.symbolic_probability import Variance from sympy.stats import Normal X = Normal('X', 0, 1) assert _test_args(Variance(X)) def test_sympy__stats__symbolic_probability__Moment(): from sympy.stats.symbolic_probability import Moment from sympy.stats import Normal X = Normal('X', 0, 1) assert _test_args(Moment(X, 3, 2, X > 3)) def test_sympy__stats__symbolic_probability__CentralMoment(): from sympy.stats.symbolic_probability import CentralMoment from sympy.stats import Normal X = Normal('X', 0, 1) assert _test_args(CentralMoment(X, 2, X > 1)) def test_sympy__stats__frv_types__DiscreteUniformDistribution(): from sympy.stats.frv_types import DiscreteUniformDistribution from sympy.core.containers import Tuple assert _test_args(DiscreteUniformDistribution(Tuple(*list(range(6))))) def test_sympy__stats__frv_types__DieDistribution(): assert _test_args(die) def test_sympy__stats__frv_types__BernoulliDistribution(): from sympy.stats.frv_types import BernoulliDistribution assert _test_args(BernoulliDistribution(S.Half, 0, 1)) def test_sympy__stats__frv_types__BinomialDistribution(): from sympy.stats.frv_types import BinomialDistribution assert _test_args(BinomialDistribution(5, S.Half, 1, 0)) def test_sympy__stats__frv_types__BetaBinomialDistribution(): from sympy.stats.frv_types import BetaBinomialDistribution assert _test_args(BetaBinomialDistribution(5, 1, 1)) def test_sympy__stats__frv_types__HypergeometricDistribution(): from sympy.stats.frv_types import HypergeometricDistribution assert _test_args(HypergeometricDistribution(10, 5, 3)) def test_sympy__stats__frv_types__RademacherDistribution(): from sympy.stats.frv_types import RademacherDistribution assert _test_args(RademacherDistribution()) def test_sympy__stats__frv_types__IdealSolitonDistribution(): from sympy.stats.frv_types import IdealSolitonDistribution assert _test_args(IdealSolitonDistribution(10)) def test_sympy__stats__frv_types__RobustSolitonDistribution(): from sympy.stats.frv_types import RobustSolitonDistribution assert _test_args(RobustSolitonDistribution(1000, 0.5, 0.1)) def test_sympy__stats__frv__FiniteDomain(): from sympy.stats.frv import FiniteDomain assert _test_args(FiniteDomain({(x, 1), (x, 2)})) # x can be 1 or 2 def test_sympy__stats__frv__SingleFiniteDomain(): from sympy.stats.frv import SingleFiniteDomain assert _test_args(SingleFiniteDomain(x, {1, 2})) # x can be 1 or 2 def test_sympy__stats__frv__ProductFiniteDomain(): from sympy.stats.frv import SingleFiniteDomain, ProductFiniteDomain xd = SingleFiniteDomain(x, {1, 2}) yd = SingleFiniteDomain(y, {1, 2}) assert _test_args(ProductFiniteDomain(xd, yd)) def test_sympy__stats__frv__ConditionalFiniteDomain(): from sympy.stats.frv import SingleFiniteDomain, ConditionalFiniteDomain xd = SingleFiniteDomain(x, {1, 2}) assert _test_args(ConditionalFiniteDomain(xd, x > 1)) def test_sympy__stats__frv__FinitePSpace(): from sympy.stats.frv import FinitePSpace, SingleFiniteDomain xd = SingleFiniteDomain(x, {1, 2, 3, 4, 5, 6}) assert _test_args(FinitePSpace(xd, {(x, 1): S.Half, (x, 2): S.Half})) xd = SingleFiniteDomain(x, {1, 2}) assert _test_args(FinitePSpace(xd, {(x, 1): S.Half, (x, 2): S.Half})) def test_sympy__stats__frv__SingleFinitePSpace(): from sympy.stats.frv import SingleFinitePSpace from sympy import Symbol assert _test_args(SingleFinitePSpace(Symbol('x'), die)) def test_sympy__stats__frv__ProductFinitePSpace(): from sympy.stats.frv import SingleFinitePSpace, ProductFinitePSpace from sympy import Symbol xp = SingleFinitePSpace(Symbol('x'), die) yp = SingleFinitePSpace(Symbol('y'), die) assert _test_args(ProductFinitePSpace(xp, yp)) @SKIP("abstract class") def test_sympy__stats__frv__SingleFiniteDistribution(): pass @SKIP("abstract class") def test_sympy__stats__crv__ContinuousDistribution(): pass def test_sympy__stats__frv_types__FiniteDistributionHandmade(): from sympy.stats.frv_types import FiniteDistributionHandmade from sympy import Dict assert _test_args(FiniteDistributionHandmade(Dict({1: 1}))) def test_sympy__stats__crv_types__ContinuousDistributionHandmade(): from sympy.stats.crv_types import ContinuousDistributionHandmade from sympy import Interval, Lambda from sympy.abc import x assert _test_args(ContinuousDistributionHandmade(Lambda(x, 2*x), Interval(0, 1))) def test_sympy__stats__drv_types__DiscreteDistributionHandmade(): from sympy.stats.drv_types import DiscreteDistributionHandmade from sympy import Lambda, FiniteSet from sympy.abc import x assert _test_args(DiscreteDistributionHandmade(Lambda(x, Rational(1, 10)), FiniteSet(*range(10)))) def test_sympy__stats__rv__Density(): from sympy.stats.rv import Density from sympy.stats.crv_types import Normal assert _test_args(Density(Normal('x', 0, 1))) def test_sympy__stats__crv_types__ArcsinDistribution(): from sympy.stats.crv_types import ArcsinDistribution assert _test_args(ArcsinDistribution(0, 1)) def test_sympy__stats__crv_types__BeniniDistribution(): from sympy.stats.crv_types import BeniniDistribution assert _test_args(BeniniDistribution(1, 1, 1)) def test_sympy__stats__crv_types__BetaDistribution(): from sympy.stats.crv_types import BetaDistribution assert _test_args(BetaDistribution(1, 1)) def test_sympy__stats__crv_types__BetaNoncentralDistribution(): from sympy.stats.crv_types import BetaNoncentralDistribution assert _test_args(BetaNoncentralDistribution(1, 1, 1)) def test_sympy__stats__crv_types__BetaPrimeDistribution(): from sympy.stats.crv_types import BetaPrimeDistribution assert _test_args(BetaPrimeDistribution(1, 1)) def test_sympy__stats__crv_types__BoundedParetoDistribution(): from sympy.stats.crv_types import BoundedParetoDistribution assert _test_args(BoundedParetoDistribution(1, 1, 2)) def test_sympy__stats__crv_types__CauchyDistribution(): from sympy.stats.crv_types import CauchyDistribution assert _test_args(CauchyDistribution(0, 1)) def test_sympy__stats__crv_types__ChiDistribution(): from sympy.stats.crv_types import ChiDistribution assert _test_args(ChiDistribution(1)) def test_sympy__stats__crv_types__ChiNoncentralDistribution(): from sympy.stats.crv_types import ChiNoncentralDistribution assert _test_args(ChiNoncentralDistribution(1,1)) def test_sympy__stats__crv_types__ChiSquaredDistribution(): from sympy.stats.crv_types import ChiSquaredDistribution assert _test_args(ChiSquaredDistribution(1)) def test_sympy__stats__crv_types__DagumDistribution(): from sympy.stats.crv_types import DagumDistribution assert _test_args(DagumDistribution(1, 1, 1)) def test_sympy__stats__crv_types__ExGaussianDistribution(): from sympy.stats.crv_types import ExGaussianDistribution assert _test_args(ExGaussianDistribution(1, 1, 1)) def test_sympy__stats__crv_types__ExponentialDistribution(): from sympy.stats.crv_types import ExponentialDistribution assert _test_args(ExponentialDistribution(1)) def test_sympy__stats__crv_types__ExponentialPowerDistribution(): from sympy.stats.crv_types import ExponentialPowerDistribution assert _test_args(ExponentialPowerDistribution(0, 1, 1)) def test_sympy__stats__crv_types__FDistributionDistribution(): from sympy.stats.crv_types import FDistributionDistribution assert _test_args(FDistributionDistribution(1, 1)) def test_sympy__stats__crv_types__FisherZDistribution(): from sympy.stats.crv_types import FisherZDistribution assert _test_args(FisherZDistribution(1, 1)) def test_sympy__stats__crv_types__FrechetDistribution(): from sympy.stats.crv_types import FrechetDistribution assert _test_args(FrechetDistribution(1, 1, 1)) def test_sympy__stats__crv_types__GammaInverseDistribution(): from sympy.stats.crv_types import GammaInverseDistribution assert _test_args(GammaInverseDistribution(1, 1)) def test_sympy__stats__crv_types__GammaDistribution(): from sympy.stats.crv_types import GammaDistribution assert _test_args(GammaDistribution(1, 1)) def test_sympy__stats__crv_types__GumbelDistribution(): from sympy.stats.crv_types import GumbelDistribution assert _test_args(GumbelDistribution(1, 1, False)) def test_sympy__stats__crv_types__GompertzDistribution(): from sympy.stats.crv_types import GompertzDistribution assert _test_args(GompertzDistribution(1, 1)) def test_sympy__stats__crv_types__KumaraswamyDistribution(): from sympy.stats.crv_types import KumaraswamyDistribution assert _test_args(KumaraswamyDistribution(1, 1)) def test_sympy__stats__crv_types__LaplaceDistribution(): from sympy.stats.crv_types import LaplaceDistribution assert _test_args(LaplaceDistribution(0, 1)) def test_sympy__stats__crv_types__LevyDistribution(): from sympy.stats.crv_types import LevyDistribution assert _test_args(LevyDistribution(0, 1)) def test_sympy__stats__crv_types__LogCauchyDistribution(): from sympy.stats.crv_types import LogCauchyDistribution assert _test_args(LogCauchyDistribution(0, 1)) def test_sympy__stats__crv_types__LogisticDistribution(): from sympy.stats.crv_types import LogisticDistribution assert _test_args(LogisticDistribution(0, 1)) def test_sympy__stats__crv_types__LogLogisticDistribution(): from sympy.stats.crv_types import LogLogisticDistribution assert _test_args(LogLogisticDistribution(1, 1)) def test_sympy__stats__crv_types__LogitNormalDistribution(): from sympy.stats.crv_types import LogitNormalDistribution assert _test_args(LogitNormalDistribution(0, 1)) def test_sympy__stats__crv_types__LogNormalDistribution(): from sympy.stats.crv_types import LogNormalDistribution assert _test_args(LogNormalDistribution(0, 1)) def test_sympy__stats__crv_types__LomaxDistribution(): from sympy.stats.crv_types import LomaxDistribution assert _test_args(LomaxDistribution(1, 2)) def test_sympy__stats__crv_types__MaxwellDistribution(): from sympy.stats.crv_types import MaxwellDistribution assert _test_args(MaxwellDistribution(1)) def test_sympy__stats__crv_types__MoyalDistribution(): from sympy.stats.crv_types import MoyalDistribution assert _test_args(MoyalDistribution(1,2)) def test_sympy__stats__crv_types__NakagamiDistribution(): from sympy.stats.crv_types import NakagamiDistribution assert _test_args(NakagamiDistribution(1, 1)) def test_sympy__stats__crv_types__NormalDistribution(): from sympy.stats.crv_types import NormalDistribution assert _test_args(NormalDistribution(0, 1)) def test_sympy__stats__crv_types__GaussianInverseDistribution(): from sympy.stats.crv_types import GaussianInverseDistribution assert _test_args(GaussianInverseDistribution(1, 1)) def test_sympy__stats__crv_types__ParetoDistribution(): from sympy.stats.crv_types import ParetoDistribution assert _test_args(ParetoDistribution(1, 1)) def test_sympy__stats__crv_types__PowerFunctionDistribution(): from sympy.stats.crv_types import PowerFunctionDistribution assert _test_args(PowerFunctionDistribution(2,0,1)) def test_sympy__stats__crv_types__QuadraticUDistribution(): from sympy.stats.crv_types import QuadraticUDistribution assert _test_args(QuadraticUDistribution(1, 2)) def test_sympy__stats__crv_types__RaisedCosineDistribution(): from sympy.stats.crv_types import RaisedCosineDistribution assert _test_args(RaisedCosineDistribution(1, 1)) def test_sympy__stats__crv_types__RayleighDistribution(): from sympy.stats.crv_types import RayleighDistribution assert _test_args(RayleighDistribution(1)) def test_sympy__stats__crv_types__ReciprocalDistribution(): from sympy.stats.crv_types import ReciprocalDistribution assert _test_args(ReciprocalDistribution(5, 30)) def test_sympy__stats__crv_types__ShiftedGompertzDistribution(): from sympy.stats.crv_types import ShiftedGompertzDistribution assert _test_args(ShiftedGompertzDistribution(1, 1)) def test_sympy__stats__crv_types__StudentTDistribution(): from sympy.stats.crv_types import StudentTDistribution assert _test_args(StudentTDistribution(1)) def test_sympy__stats__crv_types__TrapezoidalDistribution(): from sympy.stats.crv_types import TrapezoidalDistribution assert _test_args(TrapezoidalDistribution(1, 2, 3, 4)) def test_sympy__stats__crv_types__TriangularDistribution(): from sympy.stats.crv_types import TriangularDistribution assert _test_args(TriangularDistribution(-1, 0, 1)) def test_sympy__stats__crv_types__UniformDistribution(): from sympy.stats.crv_types import UniformDistribution assert _test_args(UniformDistribution(0, 1)) def test_sympy__stats__crv_types__UniformSumDistribution(): from sympy.stats.crv_types import UniformSumDistribution assert _test_args(UniformSumDistribution(1)) def test_sympy__stats__crv_types__VonMisesDistribution(): from sympy.stats.crv_types import VonMisesDistribution assert _test_args(VonMisesDistribution(1, 1)) def test_sympy__stats__crv_types__WeibullDistribution(): from sympy.stats.crv_types import WeibullDistribution assert _test_args(WeibullDistribution(1, 1)) def test_sympy__stats__crv_types__WignerSemicircleDistribution(): from sympy.stats.crv_types import WignerSemicircleDistribution assert _test_args(WignerSemicircleDistribution(1)) def test_sympy__stats__drv_types__GeometricDistribution(): from sympy.stats.drv_types import GeometricDistribution assert _test_args(GeometricDistribution(.5)) def test_sympy__stats__drv_types__HermiteDistribution(): from sympy.stats.drv_types import HermiteDistribution assert _test_args(HermiteDistribution(1, 2)) def test_sympy__stats__drv_types__LogarithmicDistribution(): from sympy.stats.drv_types import LogarithmicDistribution assert _test_args(LogarithmicDistribution(.5)) def test_sympy__stats__drv_types__NegativeBinomialDistribution(): from sympy.stats.drv_types import NegativeBinomialDistribution assert _test_args(NegativeBinomialDistribution(.5, .5)) def test_sympy__stats__drv_types__FlorySchulzDistribution(): from sympy.stats.drv_types import FlorySchulzDistribution assert _test_args(FlorySchulzDistribution(.5)) def test_sympy__stats__drv_types__PoissonDistribution(): from sympy.stats.drv_types import PoissonDistribution assert _test_args(PoissonDistribution(1)) def test_sympy__stats__drv_types__SkellamDistribution(): from sympy.stats.drv_types import SkellamDistribution assert _test_args(SkellamDistribution(1, 1)) def test_sympy__stats__drv_types__YuleSimonDistribution(): from sympy.stats.drv_types import YuleSimonDistribution assert _test_args(YuleSimonDistribution(.5)) def test_sympy__stats__drv_types__ZetaDistribution(): from sympy.stats.drv_types import ZetaDistribution assert _test_args(ZetaDistribution(1.5)) def test_sympy__stats__joint_rv__JointDistribution(): from sympy.stats.joint_rv import JointDistribution assert _test_args(JointDistribution(1, 2, 3, 4)) def test_sympy__stats__joint_rv_types__MultivariateNormalDistribution(): from sympy.stats.joint_rv_types import MultivariateNormalDistribution assert _test_args( MultivariateNormalDistribution([0, 1], [[1, 0],[0, 1]])) def test_sympy__stats__joint_rv_types__MultivariateLaplaceDistribution(): from sympy.stats.joint_rv_types import MultivariateLaplaceDistribution assert _test_args(MultivariateLaplaceDistribution([0, 1], [[1, 0],[0, 1]])) def test_sympy__stats__joint_rv_types__MultivariateTDistribution(): from sympy.stats.joint_rv_types import MultivariateTDistribution assert _test_args(MultivariateTDistribution([0, 1], [[1, 0],[0, 1]], 1)) def test_sympy__stats__joint_rv_types__NormalGammaDistribution(): from sympy.stats.joint_rv_types import NormalGammaDistribution assert _test_args(NormalGammaDistribution(1, 2, 3, 4)) def test_sympy__stats__joint_rv_types__GeneralizedMultivariateLogGammaDistribution(): from sympy.stats.joint_rv_types import GeneralizedMultivariateLogGammaDistribution v, l, mu = (4, [1, 2, 3, 4], [1, 2, 3, 4]) assert _test_args(GeneralizedMultivariateLogGammaDistribution(S.Half, v, l, mu)) def test_sympy__stats__joint_rv_types__MultivariateBetaDistribution(): from sympy.stats.joint_rv_types import MultivariateBetaDistribution assert _test_args(MultivariateBetaDistribution([1, 2, 3])) def test_sympy__stats__joint_rv_types__MultivariateEwensDistribution(): from sympy.stats.joint_rv_types import MultivariateEwensDistribution assert _test_args(MultivariateEwensDistribution(5, 1)) def test_sympy__stats__joint_rv_types__MultinomialDistribution(): from sympy.stats.joint_rv_types import MultinomialDistribution assert _test_args(MultinomialDistribution(5, [0.5, 0.1, 0.3])) def test_sympy__stats__joint_rv_types__NegativeMultinomialDistribution(): from sympy.stats.joint_rv_types import NegativeMultinomialDistribution assert _test_args(NegativeMultinomialDistribution(5, [0.5, 0.1, 0.3])) def test_sympy__stats__rv__RandomIndexedSymbol(): from sympy.stats.rv import RandomIndexedSymbol, pspace from sympy.stats.stochastic_process_types import DiscreteMarkovChain X = DiscreteMarkovChain("X") assert _test_args(RandomIndexedSymbol(X[0].symbol, pspace(X[0]))) def test_sympy__stats__rv__RandomMatrixSymbol(): from sympy.stats.rv import RandomMatrixSymbol from sympy.stats.random_matrix import RandomMatrixPSpace pspace = RandomMatrixPSpace('P') assert _test_args(RandomMatrixSymbol('M', 3, 3, pspace)) def test_sympy__stats__stochastic_process__StochasticPSpace(): from sympy.stats.stochastic_process import StochasticPSpace from sympy.stats.stochastic_process_types import StochasticProcess from sympy.stats.frv_types import BernoulliDistribution assert _test_args(StochasticPSpace("Y", StochasticProcess("Y", [1, 2, 3]), BernoulliDistribution(S.Half, 1, 0))) def test_sympy__stats__stochastic_process_types__StochasticProcess(): from sympy.stats.stochastic_process_types import StochasticProcess assert _test_args(StochasticProcess("Y", [1, 2, 3])) def test_sympy__stats__stochastic_process_types__MarkovProcess(): from sympy.stats.stochastic_process_types import MarkovProcess assert _test_args(MarkovProcess("Y", [1, 2, 3])) def test_sympy__stats__stochastic_process_types__DiscreteTimeStochasticProcess(): from sympy.stats.stochastic_process_types import DiscreteTimeStochasticProcess assert _test_args(DiscreteTimeStochasticProcess("Y", [1, 2, 3])) def test_sympy__stats__stochastic_process_types__ContinuousTimeStochasticProcess(): from sympy.stats.stochastic_process_types import ContinuousTimeStochasticProcess assert _test_args(ContinuousTimeStochasticProcess("Y", [1, 2, 3])) def test_sympy__stats__stochastic_process_types__TransitionMatrixOf(): from sympy.stats.stochastic_process_types import TransitionMatrixOf, DiscreteMarkovChain from sympy import MatrixSymbol DMC = DiscreteMarkovChain("Y") assert _test_args(TransitionMatrixOf(DMC, MatrixSymbol('T', 3, 3))) def test_sympy__stats__stochastic_process_types__GeneratorMatrixOf(): from sympy.stats.stochastic_process_types import GeneratorMatrixOf, ContinuousMarkovChain from sympy import MatrixSymbol DMC = ContinuousMarkovChain("Y") assert _test_args(GeneratorMatrixOf(DMC, MatrixSymbol('T', 3, 3))) def test_sympy__stats__stochastic_process_types__StochasticStateSpaceOf(): from sympy.stats.stochastic_process_types import StochasticStateSpaceOf, DiscreteMarkovChain DMC = DiscreteMarkovChain("Y") assert _test_args(StochasticStateSpaceOf(DMC, [0, 1, 2])) def test_sympy__stats__stochastic_process_types__DiscreteMarkovChain(): from sympy.stats.stochastic_process_types import DiscreteMarkovChain from sympy import MatrixSymbol assert _test_args(DiscreteMarkovChain("Y", [0, 1, 2], MatrixSymbol('T', 3, 3))) def test_sympy__stats__stochastic_process_types__ContinuousMarkovChain(): from sympy.stats.stochastic_process_types import ContinuousMarkovChain from sympy import MatrixSymbol assert _test_args(ContinuousMarkovChain("Y", [0, 1, 2], MatrixSymbol('T', 3, 3))) def test_sympy__stats__stochastic_process_types__BernoulliProcess(): from sympy.stats.stochastic_process_types import BernoulliProcess assert _test_args(BernoulliProcess("B", 0.5, 1, 0)) def test_sympy__stats__stochastic_process_types__CountingProcess(): from sympy.stats.stochastic_process_types import CountingProcess assert _test_args(CountingProcess("C")) def test_sympy__stats__stochastic_process_types__PoissonProcess(): from sympy.stats.stochastic_process_types import PoissonProcess assert _test_args(PoissonProcess("X", 2)) def test_sympy__stats__stochastic_process_types__WienerProcess(): from sympy.stats.stochastic_process_types import WienerProcess assert _test_args(WienerProcess("X")) def test_sympy__stats__stochastic_process_types__GammaProcess(): from sympy.stats.stochastic_process_types import GammaProcess assert _test_args(GammaProcess("X", 1, 2)) def test_sympy__stats__random_matrix__RandomMatrixPSpace(): from sympy.stats.random_matrix import RandomMatrixPSpace from sympy.stats.random_matrix_models import RandomMatrixEnsembleModel model = RandomMatrixEnsembleModel('R', 3) assert _test_args(RandomMatrixPSpace('P', model=model)) def test_sympy__stats__random_matrix_models__RandomMatrixEnsembleModel(): from sympy.stats.random_matrix_models import RandomMatrixEnsembleModel assert _test_args(RandomMatrixEnsembleModel('R', 3)) def test_sympy__stats__random_matrix_models__GaussianEnsembleModel(): from sympy.stats.random_matrix_models import GaussianEnsembleModel assert _test_args(GaussianEnsembleModel('G', 3)) def test_sympy__stats__random_matrix_models__GaussianUnitaryEnsembleModel(): from sympy.stats.random_matrix_models import GaussianUnitaryEnsembleModel assert _test_args(GaussianUnitaryEnsembleModel('U', 3)) def test_sympy__stats__random_matrix_models__GaussianOrthogonalEnsembleModel(): from sympy.stats.random_matrix_models import GaussianOrthogonalEnsembleModel assert _test_args(GaussianOrthogonalEnsembleModel('U', 3)) def test_sympy__stats__random_matrix_models__GaussianSymplecticEnsembleModel(): from sympy.stats.random_matrix_models import GaussianSymplecticEnsembleModel assert _test_args(GaussianSymplecticEnsembleModel('U', 3)) def test_sympy__stats__random_matrix_models__CircularEnsembleModel(): from sympy.stats.random_matrix_models import CircularEnsembleModel assert _test_args(CircularEnsembleModel('C', 3)) def test_sympy__stats__random_matrix_models__CircularUnitaryEnsembleModel(): from sympy.stats.random_matrix_models import CircularUnitaryEnsembleModel assert _test_args(CircularUnitaryEnsembleModel('U', 3)) def test_sympy__stats__random_matrix_models__CircularOrthogonalEnsembleModel(): from sympy.stats.random_matrix_models import CircularOrthogonalEnsembleModel assert _test_args(CircularOrthogonalEnsembleModel('O', 3)) def test_sympy__stats__random_matrix_models__CircularSymplecticEnsembleModel(): from sympy.stats.random_matrix_models import CircularSymplecticEnsembleModel assert _test_args(CircularSymplecticEnsembleModel('S', 3)) def test_sympy__stats__symbolic_multivariate_probability__ExpectationMatrix(): from sympy.stats import ExpectationMatrix from sympy.stats.rv import RandomMatrixSymbol assert _test_args(ExpectationMatrix(RandomMatrixSymbol('R', 2, 1))) def test_sympy__stats__symbolic_multivariate_probability__VarianceMatrix(): from sympy.stats import VarianceMatrix from sympy.stats.rv import RandomMatrixSymbol assert _test_args(VarianceMatrix(RandomMatrixSymbol('R', 3, 1))) def test_sympy__stats__symbolic_multivariate_probability__CrossCovarianceMatrix(): from sympy.stats import CrossCovarianceMatrix from sympy.stats.rv import RandomMatrixSymbol assert _test_args(CrossCovarianceMatrix(RandomMatrixSymbol('R', 3, 1), RandomMatrixSymbol('X', 3, 1))) def test_sympy__stats__matrix_distributions__MatrixPSpace(): from sympy.stats.matrix_distributions import MatrixDistribution, MatrixPSpace from sympy import Matrix M = MatrixDistribution(1, Matrix([[1, 0], [0, 1]])) assert _test_args(MatrixPSpace('M', M, 2, 2)) def test_sympy__stats__matrix_distributions__MatrixDistribution(): from sympy.stats.matrix_distributions import MatrixDistribution from sympy import Matrix assert _test_args(MatrixDistribution(1, Matrix([[1, 0], [0, 1]]))) def test_sympy__stats__matrix_distributions__MatrixGammaDistribution(): from sympy.stats.matrix_distributions import MatrixGammaDistribution from sympy import Matrix assert _test_args(MatrixGammaDistribution(3, 4, Matrix([[1, 0], [0, 1]]))) def test_sympy__stats__matrix_distributions__WishartDistribution(): from sympy.stats.matrix_distributions import WishartDistribution from sympy import Matrix assert _test_args(WishartDistribution(3, Matrix([[1, 0], [0, 1]]))) def test_sympy__stats__matrix_distributions__MatrixNormalDistribution(): from sympy.stats.matrix_distributions import MatrixNormalDistribution from sympy import MatrixSymbol L = MatrixSymbol('L', 1, 2) S1 = MatrixSymbol('S1', 1, 1) S2 = MatrixSymbol('S2', 2, 2) assert _test_args(MatrixNormalDistribution(L, S1, S2)) def test_sympy__stats__matrix_distributions__MatrixStudentTDistribution(): from sympy.stats.matrix_distributions import MatrixStudentTDistribution from sympy import MatrixSymbol v = symbols('v', positive=True) Omega = MatrixSymbol('Omega', 3, 3) Sigma = MatrixSymbol('Sigma', 1, 1) Location = MatrixSymbol('Location', 1, 3) assert _test_args(MatrixStudentTDistribution(v, Location, Omega, Sigma)) def test_sympy__utilities__matchpy_connector__WildDot(): from sympy.utilities.matchpy_connector import WildDot assert _test_args(WildDot("w_")) def test_sympy__utilities__matchpy_connector__WildPlus(): from sympy.utilities.matchpy_connector import WildPlus assert _test_args(WildPlus("w__")) def test_sympy__utilities__matchpy_connector__WildStar(): from sympy.utilities.matchpy_connector import WildStar assert _test_args(WildStar("w___")) def test_sympy__core__symbol__Str(): from sympy.core.symbol import Str assert _test_args(Str('t')) def test_sympy__core__symbol__Dummy(): from sympy.core.symbol import Dummy assert _test_args(Dummy('t')) def test_sympy__core__symbol__Symbol(): from sympy.core.symbol import Symbol assert _test_args(Symbol('t')) def test_sympy__core__symbol__Wild(): from sympy.core.symbol import Wild assert _test_args(Wild('x', exclude=[x])) @SKIP("abstract class") def test_sympy__functions__combinatorial__factorials__CombinatorialFunction(): pass def test_sympy__functions__combinatorial__factorials__FallingFactorial(): from sympy.functions.combinatorial.factorials import FallingFactorial assert _test_args(FallingFactorial(2, x)) def test_sympy__functions__combinatorial__factorials__MultiFactorial(): from sympy.functions.combinatorial.factorials import MultiFactorial assert _test_args(MultiFactorial(x)) def test_sympy__functions__combinatorial__factorials__RisingFactorial(): from sympy.functions.combinatorial.factorials import RisingFactorial assert _test_args(RisingFactorial(2, x)) def test_sympy__functions__combinatorial__factorials__binomial(): from sympy.functions.combinatorial.factorials import binomial assert _test_args(binomial(2, x)) def test_sympy__functions__combinatorial__factorials__subfactorial(): from sympy.functions.combinatorial.factorials import subfactorial assert _test_args(subfactorial(1)) def test_sympy__functions__combinatorial__factorials__factorial(): from sympy.functions.combinatorial.factorials import factorial assert _test_args(factorial(x)) def test_sympy__functions__combinatorial__factorials__factorial2(): from sympy.functions.combinatorial.factorials import factorial2 assert _test_args(factorial2(x)) def test_sympy__functions__combinatorial__numbers__bell(): from sympy.functions.combinatorial.numbers import bell assert _test_args(bell(x, y)) def test_sympy__functions__combinatorial__numbers__bernoulli(): from sympy.functions.combinatorial.numbers import bernoulli assert _test_args(bernoulli(x)) def test_sympy__functions__combinatorial__numbers__catalan(): from sympy.functions.combinatorial.numbers import catalan assert _test_args(catalan(x)) def test_sympy__functions__combinatorial__numbers__genocchi(): from sympy.functions.combinatorial.numbers import genocchi assert _test_args(genocchi(x)) def test_sympy__functions__combinatorial__numbers__euler(): from sympy.functions.combinatorial.numbers import euler assert _test_args(euler(x)) def test_sympy__functions__combinatorial__numbers__carmichael(): from sympy.functions.combinatorial.numbers import carmichael assert _test_args(carmichael(x)) def test_sympy__functions__combinatorial__numbers__motzkin(): from sympy.functions.combinatorial.numbers import motzkin assert _test_args(motzkin(5)) def test_sympy__functions__combinatorial__numbers__fibonacci(): from sympy.functions.combinatorial.numbers import fibonacci assert _test_args(fibonacci(x)) def test_sympy__functions__combinatorial__numbers__tribonacci(): from sympy.functions.combinatorial.numbers import tribonacci assert _test_args(tribonacci(x)) def test_sympy__functions__combinatorial__numbers__harmonic(): from sympy.functions.combinatorial.numbers import harmonic assert _test_args(harmonic(x, 2)) def test_sympy__functions__combinatorial__numbers__lucas(): from sympy.functions.combinatorial.numbers import lucas assert _test_args(lucas(x)) def test_sympy__functions__combinatorial__numbers__partition(): from sympy.core.symbol import Symbol from sympy.functions.combinatorial.numbers import partition assert _test_args(partition(Symbol('a', integer=True))) def test_sympy__functions__elementary__complexes__Abs(): from sympy.functions.elementary.complexes import Abs assert _test_args(Abs(x)) def test_sympy__functions__elementary__complexes__adjoint(): from sympy.functions.elementary.complexes import adjoint assert _test_args(adjoint(x)) def test_sympy__functions__elementary__complexes__arg(): from sympy.functions.elementary.complexes import arg assert _test_args(arg(x)) def test_sympy__functions__elementary__complexes__conjugate(): from sympy.functions.elementary.complexes import conjugate assert _test_args(conjugate(x)) def test_sympy__functions__elementary__complexes__im(): from sympy.functions.elementary.complexes import im assert _test_args(im(x)) def test_sympy__functions__elementary__complexes__re(): from sympy.functions.elementary.complexes import re assert _test_args(re(x)) def test_sympy__functions__elementary__complexes__sign(): from sympy.functions.elementary.complexes import sign assert _test_args(sign(x)) def test_sympy__functions__elementary__complexes__polar_lift(): from sympy.functions.elementary.complexes import polar_lift assert _test_args(polar_lift(x)) def test_sympy__functions__elementary__complexes__periodic_argument(): from sympy.functions.elementary.complexes import periodic_argument assert _test_args(periodic_argument(x, y)) def test_sympy__functions__elementary__complexes__principal_branch(): from sympy.functions.elementary.complexes import principal_branch assert _test_args(principal_branch(x, y)) def test_sympy__functions__elementary__complexes__transpose(): from sympy.functions.elementary.complexes import transpose assert _test_args(transpose(x)) def test_sympy__functions__elementary__exponential__LambertW(): from sympy.functions.elementary.exponential import LambertW assert _test_args(LambertW(2)) @SKIP("abstract class") def test_sympy__functions__elementary__exponential__ExpBase(): pass def test_sympy__functions__elementary__exponential__exp(): from sympy.functions.elementary.exponential import exp assert _test_args(exp(2)) def test_sympy__functions__elementary__exponential__exp_polar(): from sympy.functions.elementary.exponential import exp_polar assert _test_args(exp_polar(2)) def test_sympy__functions__elementary__exponential__log(): from sympy.functions.elementary.exponential import log assert _test_args(log(2)) @SKIP("abstract class") def test_sympy__functions__elementary__hyperbolic__HyperbolicFunction(): pass @SKIP("abstract class") def test_sympy__functions__elementary__hyperbolic__ReciprocalHyperbolicFunction(): pass @SKIP("abstract class") def test_sympy__functions__elementary__hyperbolic__InverseHyperbolicFunction(): pass def test_sympy__functions__elementary__hyperbolic__acosh(): from sympy.functions.elementary.hyperbolic import acosh assert _test_args(acosh(2)) def test_sympy__functions__elementary__hyperbolic__acoth(): from sympy.functions.elementary.hyperbolic import acoth assert _test_args(acoth(2)) def test_sympy__functions__elementary__hyperbolic__asinh(): from sympy.functions.elementary.hyperbolic import asinh assert _test_args(asinh(2)) def test_sympy__functions__elementary__hyperbolic__atanh(): from sympy.functions.elementary.hyperbolic import atanh assert _test_args(atanh(2)) def test_sympy__functions__elementary__hyperbolic__asech(): from sympy.functions.elementary.hyperbolic import asech assert _test_args(asech(2)) def test_sympy__functions__elementary__hyperbolic__acsch(): from sympy.functions.elementary.hyperbolic import acsch assert _test_args(acsch(2)) def test_sympy__functions__elementary__hyperbolic__cosh(): from sympy.functions.elementary.hyperbolic import cosh assert _test_args(cosh(2)) def test_sympy__functions__elementary__hyperbolic__coth(): from sympy.functions.elementary.hyperbolic import coth assert _test_args(coth(2)) def test_sympy__functions__elementary__hyperbolic__csch(): from sympy.functions.elementary.hyperbolic import csch assert _test_args(csch(2)) def test_sympy__functions__elementary__hyperbolic__sech(): from sympy.functions.elementary.hyperbolic import sech assert _test_args(sech(2)) def test_sympy__functions__elementary__hyperbolic__sinh(): from sympy.functions.elementary.hyperbolic import sinh assert _test_args(sinh(2)) def test_sympy__functions__elementary__hyperbolic__tanh(): from sympy.functions.elementary.hyperbolic import tanh assert _test_args(tanh(2)) @SKIP("does this work at all?") def test_sympy__functions__elementary__integers__RoundFunction(): from sympy.functions.elementary.integers import RoundFunction assert _test_args(RoundFunction()) def test_sympy__functions__elementary__integers__ceiling(): from sympy.functions.elementary.integers import ceiling assert _test_args(ceiling(x)) def test_sympy__functions__elementary__integers__floor(): from sympy.functions.elementary.integers import floor assert _test_args(floor(x)) def test_sympy__functions__elementary__integers__frac(): from sympy.functions.elementary.integers import frac assert _test_args(frac(x)) def test_sympy__functions__elementary__miscellaneous__IdentityFunction(): from sympy.functions.elementary.miscellaneous import IdentityFunction assert _test_args(IdentityFunction()) def test_sympy__functions__elementary__miscellaneous__Max(): from sympy.functions.elementary.miscellaneous import Max assert _test_args(Max(x, 2)) def test_sympy__functions__elementary__miscellaneous__Min(): from sympy.functions.elementary.miscellaneous import Min assert _test_args(Min(x, 2)) @SKIP("abstract class") def test_sympy__functions__elementary__miscellaneous__MinMaxBase(): pass def test_sympy__functions__elementary__piecewise__ExprCondPair(): from sympy.functions.elementary.piecewise import ExprCondPair assert _test_args(ExprCondPair(1, True)) def test_sympy__functions__elementary__piecewise__Piecewise(): from sympy.functions.elementary.piecewise import Piecewise assert _test_args(Piecewise((1, x >= 0), (0, True))) @SKIP("abstract class") def test_sympy__functions__elementary__trigonometric__TrigonometricFunction(): pass @SKIP("abstract class") def test_sympy__functions__elementary__trigonometric__ReciprocalTrigonometricFunction(): pass @SKIP("abstract class") def test_sympy__functions__elementary__trigonometric__InverseTrigonometricFunction(): pass def test_sympy__functions__elementary__trigonometric__acos(): from sympy.functions.elementary.trigonometric import acos assert _test_args(acos(2)) def test_sympy__functions__elementary__trigonometric__acot(): from sympy.functions.elementary.trigonometric import acot assert _test_args(acot(2)) def test_sympy__functions__elementary__trigonometric__asin(): from sympy.functions.elementary.trigonometric import asin assert _test_args(asin(2)) def test_sympy__functions__elementary__trigonometric__asec(): from sympy.functions.elementary.trigonometric import asec assert _test_args(asec(2)) def test_sympy__functions__elementary__trigonometric__acsc(): from sympy.functions.elementary.trigonometric import acsc assert _test_args(acsc(2)) def test_sympy__functions__elementary__trigonometric__atan(): from sympy.functions.elementary.trigonometric import atan assert _test_args(atan(2)) def test_sympy__functions__elementary__trigonometric__atan2(): from sympy.functions.elementary.trigonometric import atan2 assert _test_args(atan2(2, 3)) def test_sympy__functions__elementary__trigonometric__cos(): from sympy.functions.elementary.trigonometric import cos assert _test_args(cos(2)) def test_sympy__functions__elementary__trigonometric__csc(): from sympy.functions.elementary.trigonometric import csc assert _test_args(csc(2)) def test_sympy__functions__elementary__trigonometric__cot(): from sympy.functions.elementary.trigonometric import cot assert _test_args(cot(2)) def test_sympy__functions__elementary__trigonometric__sin(): assert _test_args(sin(2)) def test_sympy__functions__elementary__trigonometric__sinc(): from sympy.functions.elementary.trigonometric import sinc assert _test_args(sinc(2)) def test_sympy__functions__elementary__trigonometric__sec(): from sympy.functions.elementary.trigonometric import sec assert _test_args(sec(2)) def test_sympy__functions__elementary__trigonometric__tan(): from sympy.functions.elementary.trigonometric import tan assert _test_args(tan(2)) @SKIP("abstract class") def test_sympy__functions__special__bessel__BesselBase(): pass @SKIP("abstract class") def test_sympy__functions__special__bessel__SphericalBesselBase(): pass @SKIP("abstract class") def test_sympy__functions__special__bessel__SphericalHankelBase(): pass def test_sympy__functions__special__bessel__besseli(): from sympy.functions.special.bessel import besseli assert _test_args(besseli(x, 1)) def test_sympy__functions__special__bessel__besselj(): from sympy.functions.special.bessel import besselj assert _test_args(besselj(x, 1)) def test_sympy__functions__special__bessel__besselk(): from sympy.functions.special.bessel import besselk assert _test_args(besselk(x, 1)) def test_sympy__functions__special__bessel__bessely(): from sympy.functions.special.bessel import bessely assert _test_args(bessely(x, 1)) def test_sympy__functions__special__bessel__hankel1(): from sympy.functions.special.bessel import hankel1 assert _test_args(hankel1(x, 1)) def test_sympy__functions__special__bessel__hankel2(): from sympy.functions.special.bessel import hankel2 assert _test_args(hankel2(x, 1)) def test_sympy__functions__special__bessel__jn(): from sympy.functions.special.bessel import jn assert _test_args(jn(0, x)) def test_sympy__functions__special__bessel__yn(): from sympy.functions.special.bessel import yn assert _test_args(yn(0, x)) def test_sympy__functions__special__bessel__hn1(): from sympy.functions.special.bessel import hn1 assert _test_args(hn1(0, x)) def test_sympy__functions__special__bessel__hn2(): from sympy.functions.special.bessel import hn2 assert _test_args(hn2(0, x)) def test_sympy__functions__special__bessel__AiryBase(): pass def test_sympy__functions__special__bessel__airyai(): from sympy.functions.special.bessel import airyai assert _test_args(airyai(2)) def test_sympy__functions__special__bessel__airybi(): from sympy.functions.special.bessel import airybi assert _test_args(airybi(2)) def test_sympy__functions__special__bessel__airyaiprime(): from sympy.functions.special.bessel import airyaiprime assert _test_args(airyaiprime(2)) def test_sympy__functions__special__bessel__airybiprime(): from sympy.functions.special.bessel import airybiprime assert _test_args(airybiprime(2)) def test_sympy__functions__special__bessel__marcumq(): from sympy.functions.special.bessel import marcumq assert _test_args(marcumq(x, y, z)) def test_sympy__functions__special__elliptic_integrals__elliptic_k(): from sympy.functions.special.elliptic_integrals import elliptic_k as K assert _test_args(K(x)) def test_sympy__functions__special__elliptic_integrals__elliptic_f(): from sympy.functions.special.elliptic_integrals import elliptic_f as F assert _test_args(F(x, y)) def test_sympy__functions__special__elliptic_integrals__elliptic_e(): from sympy.functions.special.elliptic_integrals import elliptic_e as E assert _test_args(E(x)) assert _test_args(E(x, y)) def test_sympy__functions__special__elliptic_integrals__elliptic_pi(): from sympy.functions.special.elliptic_integrals import elliptic_pi as P assert _test_args(P(x, y)) assert _test_args(P(x, y, z)) def test_sympy__functions__special__delta_functions__DiracDelta(): from sympy.functions.special.delta_functions import DiracDelta assert _test_args(DiracDelta(x, 1)) def test_sympy__functions__special__singularity_functions__SingularityFunction(): from sympy.functions.special.singularity_functions import SingularityFunction assert _test_args(SingularityFunction(x, y, z)) def test_sympy__functions__special__delta_functions__Heaviside(): from sympy.functions.special.delta_functions import Heaviside assert _test_args(Heaviside(x)) def test_sympy__functions__special__error_functions__erf(): from sympy.functions.special.error_functions import erf assert _test_args(erf(2)) def test_sympy__functions__special__error_functions__erfc(): from sympy.functions.special.error_functions import erfc assert _test_args(erfc(2)) def test_sympy__functions__special__error_functions__erfi(): from sympy.functions.special.error_functions import erfi assert _test_args(erfi(2)) def test_sympy__functions__special__error_functions__erf2(): from sympy.functions.special.error_functions import erf2 assert _test_args(erf2(2, 3)) def test_sympy__functions__special__error_functions__erfinv(): from sympy.functions.special.error_functions import erfinv assert _test_args(erfinv(2)) def test_sympy__functions__special__error_functions__erfcinv(): from sympy.functions.special.error_functions import erfcinv assert _test_args(erfcinv(2)) def test_sympy__functions__special__error_functions__erf2inv(): from sympy.functions.special.error_functions import erf2inv assert _test_args(erf2inv(2, 3)) @SKIP("abstract class") def test_sympy__functions__special__error_functions__FresnelIntegral(): pass def test_sympy__functions__special__error_functions__fresnels(): from sympy.functions.special.error_functions import fresnels assert _test_args(fresnels(2)) def test_sympy__functions__special__error_functions__fresnelc(): from sympy.functions.special.error_functions import fresnelc assert _test_args(fresnelc(2)) def test_sympy__functions__special__error_functions__erfs(): from sympy.functions.special.error_functions import _erfs assert _test_args(_erfs(2)) def test_sympy__functions__special__error_functions__Ei(): from sympy.functions.special.error_functions import Ei assert _test_args(Ei(2)) def test_sympy__functions__special__error_functions__li(): from sympy.functions.special.error_functions import li assert _test_args(li(2)) def test_sympy__functions__special__error_functions__Li(): from sympy.functions.special.error_functions import Li assert _test_args(Li(2)) @SKIP("abstract class") def test_sympy__functions__special__error_functions__TrigonometricIntegral(): pass def test_sympy__functions__special__error_functions__Si(): from sympy.functions.special.error_functions import Si assert _test_args(Si(2)) def test_sympy__functions__special__error_functions__Ci(): from sympy.functions.special.error_functions import Ci assert _test_args(Ci(2)) def test_sympy__functions__special__error_functions__Shi(): from sympy.functions.special.error_functions import Shi assert _test_args(Shi(2)) def test_sympy__functions__special__error_functions__Chi(): from sympy.functions.special.error_functions import Chi assert _test_args(Chi(2)) def test_sympy__functions__special__error_functions__expint(): from sympy.functions.special.error_functions import expint assert _test_args(expint(y, x)) def test_sympy__functions__special__gamma_functions__gamma(): from sympy.functions.special.gamma_functions import gamma assert _test_args(gamma(x)) def test_sympy__functions__special__gamma_functions__loggamma(): from sympy.functions.special.gamma_functions import loggamma assert _test_args(loggamma(2)) def test_sympy__functions__special__gamma_functions__lowergamma(): from sympy.functions.special.gamma_functions import lowergamma assert _test_args(lowergamma(x, 2)) def test_sympy__functions__special__gamma_functions__polygamma(): from sympy.functions.special.gamma_functions import polygamma assert _test_args(polygamma(x, 2)) def test_sympy__functions__special__gamma_functions__digamma(): from sympy.functions.special.gamma_functions import digamma assert _test_args(digamma(x)) def test_sympy__functions__special__gamma_functions__trigamma(): from sympy.functions.special.gamma_functions import trigamma assert _test_args(trigamma(x)) def test_sympy__functions__special__gamma_functions__uppergamma(): from sympy.functions.special.gamma_functions import uppergamma assert _test_args(uppergamma(x, 2)) def test_sympy__functions__special__gamma_functions__multigamma(): from sympy.functions.special.gamma_functions import multigamma assert _test_args(multigamma(x, 1)) def test_sympy__functions__special__beta_functions__beta(): from sympy.functions.special.beta_functions import beta assert _test_args(beta(x)) assert _test_args(beta(x, x)) def test_sympy__functions__special__beta_functions__betainc(): from sympy.functions.special.beta_functions import betainc assert _test_args(betainc(a, b, x, y)) def test_sympy__functions__special__beta_functions__betainc_regularized(): from sympy.functions.special.beta_functions import betainc_regularized assert _test_args(betainc_regularized(a, b, x, y)) def test_sympy__functions__special__mathieu_functions__MathieuBase(): pass def test_sympy__functions__special__mathieu_functions__mathieus(): from sympy.functions.special.mathieu_functions import mathieus assert _test_args(mathieus(1, 1, 1)) def test_sympy__functions__special__mathieu_functions__mathieuc(): from sympy.functions.special.mathieu_functions import mathieuc assert _test_args(mathieuc(1, 1, 1)) def test_sympy__functions__special__mathieu_functions__mathieusprime(): from sympy.functions.special.mathieu_functions import mathieusprime assert _test_args(mathieusprime(1, 1, 1)) def test_sympy__functions__special__mathieu_functions__mathieucprime(): from sympy.functions.special.mathieu_functions import mathieucprime assert _test_args(mathieucprime(1, 1, 1)) @SKIP("abstract class") def test_sympy__functions__special__hyper__TupleParametersBase(): pass @SKIP("abstract class") def test_sympy__functions__special__hyper__TupleArg(): pass def test_sympy__functions__special__hyper__hyper(): from sympy.functions.special.hyper import hyper assert _test_args(hyper([1, 2, 3], [4, 5], x)) def test_sympy__functions__special__hyper__meijerg(): from sympy.functions.special.hyper import meijerg assert _test_args(meijerg([1, 2, 3], [4, 5], [6], [], x)) @SKIP("abstract class") def test_sympy__functions__special__hyper__HyperRep(): pass def test_sympy__functions__special__hyper__HyperRep_power1(): from sympy.functions.special.hyper import HyperRep_power1 assert _test_args(HyperRep_power1(x, y)) def test_sympy__functions__special__hyper__HyperRep_power2(): from sympy.functions.special.hyper import HyperRep_power2 assert _test_args(HyperRep_power2(x, y)) def test_sympy__functions__special__hyper__HyperRep_log1(): from sympy.functions.special.hyper import HyperRep_log1 assert _test_args(HyperRep_log1(x)) def test_sympy__functions__special__hyper__HyperRep_atanh(): from sympy.functions.special.hyper import HyperRep_atanh assert _test_args(HyperRep_atanh(x)) def test_sympy__functions__special__hyper__HyperRep_asin1(): from sympy.functions.special.hyper import HyperRep_asin1 assert _test_args(HyperRep_asin1(x)) def test_sympy__functions__special__hyper__HyperRep_asin2(): from sympy.functions.special.hyper import HyperRep_asin2 assert _test_args(HyperRep_asin2(x)) def test_sympy__functions__special__hyper__HyperRep_sqrts1(): from sympy.functions.special.hyper import HyperRep_sqrts1 assert _test_args(HyperRep_sqrts1(x, y)) def test_sympy__functions__special__hyper__HyperRep_sqrts2(): from sympy.functions.special.hyper import HyperRep_sqrts2 assert _test_args(HyperRep_sqrts2(x, y)) def test_sympy__functions__special__hyper__HyperRep_log2(): from sympy.functions.special.hyper import HyperRep_log2 assert _test_args(HyperRep_log2(x)) def test_sympy__functions__special__hyper__HyperRep_cosasin(): from sympy.functions.special.hyper import HyperRep_cosasin assert _test_args(HyperRep_cosasin(x, y)) def test_sympy__functions__special__hyper__HyperRep_sinasin(): from sympy.functions.special.hyper import HyperRep_sinasin assert _test_args(HyperRep_sinasin(x, y)) def test_sympy__functions__special__hyper__appellf1(): from sympy.functions.special.hyper import appellf1 a, b1, b2, c, x, y = symbols('a b1 b2 c x y') assert _test_args(appellf1(a, b1, b2, c, x, y)) @SKIP("abstract class") def test_sympy__functions__special__polynomials__OrthogonalPolynomial(): pass def test_sympy__functions__special__polynomials__jacobi(): from sympy.functions.special.polynomials import jacobi assert _test_args(jacobi(x, 2, 2, 2)) def test_sympy__functions__special__polynomials__gegenbauer(): from sympy.functions.special.polynomials import gegenbauer assert _test_args(gegenbauer(x, 2, 2)) def test_sympy__functions__special__polynomials__chebyshevt(): from sympy.functions.special.polynomials import chebyshevt assert _test_args(chebyshevt(x, 2)) def test_sympy__functions__special__polynomials__chebyshevt_root(): from sympy.functions.special.polynomials import chebyshevt_root assert _test_args(chebyshevt_root(3, 2)) def test_sympy__functions__special__polynomials__chebyshevu(): from sympy.functions.special.polynomials import chebyshevu assert _test_args(chebyshevu(x, 2)) def test_sympy__functions__special__polynomials__chebyshevu_root(): from sympy.functions.special.polynomials import chebyshevu_root assert _test_args(chebyshevu_root(3, 2)) def test_sympy__functions__special__polynomials__hermite(): from sympy.functions.special.polynomials import hermite assert _test_args(hermite(x, 2)) def test_sympy__functions__special__polynomials__legendre(): from sympy.functions.special.polynomials import legendre assert _test_args(legendre(x, 2)) def test_sympy__functions__special__polynomials__assoc_legendre(): from sympy.functions.special.polynomials import assoc_legendre assert _test_args(assoc_legendre(x, 0, y)) def test_sympy__functions__special__polynomials__laguerre(): from sympy.functions.special.polynomials import laguerre assert _test_args(laguerre(x, 2)) def test_sympy__functions__special__polynomials__assoc_laguerre(): from sympy.functions.special.polynomials import assoc_laguerre assert _test_args(assoc_laguerre(x, 0, y)) def test_sympy__functions__special__spherical_harmonics__Ynm(): from sympy.functions.special.spherical_harmonics import Ynm assert _test_args(Ynm(1, 1, x, y)) def test_sympy__functions__special__spherical_harmonics__Znm(): from sympy.functions.special.spherical_harmonics import Znm assert _test_args(Znm(1, 1, x, y)) def test_sympy__functions__special__tensor_functions__LeviCivita(): from sympy.functions.special.tensor_functions import LeviCivita assert _test_args(LeviCivita(x, y, 2)) def test_sympy__functions__special__tensor_functions__KroneckerDelta(): from sympy.functions.special.tensor_functions import KroneckerDelta assert _test_args(KroneckerDelta(x, y)) def test_sympy__functions__special__zeta_functions__dirichlet_eta(): from sympy.functions.special.zeta_functions import dirichlet_eta assert _test_args(dirichlet_eta(x)) def test_sympy__functions__special__zeta_functions__riemann_xi(): from sympy.functions.special.zeta_functions import riemann_xi assert _test_args(riemann_xi(x)) def test_sympy__functions__special__zeta_functions__zeta(): from sympy.functions.special.zeta_functions import zeta assert _test_args(zeta(101)) def test_sympy__functions__special__zeta_functions__lerchphi(): from sympy.functions.special.zeta_functions import lerchphi assert _test_args(lerchphi(x, y, z)) def test_sympy__functions__special__zeta_functions__polylog(): from sympy.functions.special.zeta_functions import polylog assert _test_args(polylog(x, y)) def test_sympy__functions__special__zeta_functions__stieltjes(): from sympy.functions.special.zeta_functions import stieltjes assert _test_args(stieltjes(x, y)) def test_sympy__integrals__integrals__Integral(): from sympy.integrals.integrals import Integral assert _test_args(Integral(2, (x, 0, 1))) def test_sympy__integrals__risch__NonElementaryIntegral(): from sympy.integrals.risch import NonElementaryIntegral assert _test_args(NonElementaryIntegral(exp(-x**2), x)) @SKIP("abstract class") def test_sympy__integrals__transforms__IntegralTransform(): pass def test_sympy__integrals__transforms__MellinTransform(): from sympy.integrals.transforms import MellinTransform assert _test_args(MellinTransform(2, x, y)) def test_sympy__integrals__transforms__InverseMellinTransform(): from sympy.integrals.transforms import InverseMellinTransform assert _test_args(InverseMellinTransform(2, x, y, 0, 1)) def test_sympy__integrals__transforms__LaplaceTransform(): from sympy.integrals.transforms import LaplaceTransform assert _test_args(LaplaceTransform(2, x, y)) def test_sympy__integrals__transforms__InverseLaplaceTransform(): from sympy.integrals.transforms import InverseLaplaceTransform assert _test_args(InverseLaplaceTransform(2, x, y, 0)) @SKIP("abstract class") def test_sympy__integrals__transforms__FourierTypeTransform(): pass def test_sympy__integrals__transforms__InverseFourierTransform(): from sympy.integrals.transforms import InverseFourierTransform assert _test_args(InverseFourierTransform(2, x, y)) def test_sympy__integrals__transforms__FourierTransform(): from sympy.integrals.transforms import FourierTransform assert _test_args(FourierTransform(2, x, y)) @SKIP("abstract class") def test_sympy__integrals__transforms__SineCosineTypeTransform(): pass def test_sympy__integrals__transforms__InverseSineTransform(): from sympy.integrals.transforms import InverseSineTransform assert _test_args(InverseSineTransform(2, x, y)) def test_sympy__integrals__transforms__SineTransform(): from sympy.integrals.transforms import SineTransform assert _test_args(SineTransform(2, x, y)) def test_sympy__integrals__transforms__InverseCosineTransform(): from sympy.integrals.transforms import InverseCosineTransform assert _test_args(InverseCosineTransform(2, x, y)) def test_sympy__integrals__transforms__CosineTransform(): from sympy.integrals.transforms import CosineTransform assert _test_args(CosineTransform(2, x, y)) @SKIP("abstract class") def test_sympy__integrals__transforms__HankelTypeTransform(): pass def test_sympy__integrals__transforms__InverseHankelTransform(): from sympy.integrals.transforms import InverseHankelTransform assert _test_args(InverseHankelTransform(2, x, y, 0)) def test_sympy__integrals__transforms__HankelTransform(): from sympy.integrals.transforms import HankelTransform assert _test_args(HankelTransform(2, x, y, 0)) @XFAIL def test_sympy__liealgebras__cartan_type__CartanType_generator(): from sympy.liealgebras.cartan_type import CartanType_generator assert _test_args(CartanType_generator("A2")) @XFAIL def test_sympy__liealgebras__cartan_type__Standard_Cartan(): from sympy.liealgebras.cartan_type import Standard_Cartan assert _test_args(Standard_Cartan("A", 2)) @XFAIL def test_sympy__liealgebras__weyl_group__WeylGroup(): from sympy.liealgebras.weyl_group import WeylGroup assert _test_args(WeylGroup("B4")) @XFAIL def test_sympy__liealgebras__root_system__RootSystem(): from sympy.liealgebras.root_system import RootSystem assert _test_args(RootSystem("A2")) @XFAIL def test_sympy__liealgebras__type_a__TypeA(): from sympy.liealgebras.type_a import TypeA assert _test_args(TypeA(2)) @XFAIL def test_sympy__liealgebras__type_b__TypeB(): from sympy.liealgebras.type_b import TypeB assert _test_args(TypeB(4)) @XFAIL def test_sympy__liealgebras__type_c__TypeC(): from sympy.liealgebras.type_c import TypeC assert _test_args(TypeC(4)) @XFAIL def test_sympy__liealgebras__type_d__TypeD(): from sympy.liealgebras.type_d import TypeD assert _test_args(TypeD(4)) @XFAIL def test_sympy__liealgebras__type_e__TypeE(): from sympy.liealgebras.type_e import TypeE assert _test_args(TypeE(6)) @XFAIL def test_sympy__liealgebras__type_f__TypeF(): from sympy.liealgebras.type_f import TypeF assert _test_args(TypeF(4)) @XFAIL def test_sympy__liealgebras__type_g__TypeG(): from sympy.liealgebras.type_g import TypeG assert _test_args(TypeG(2)) def test_sympy__logic__boolalg__And(): from sympy.logic.boolalg import And assert _test_args(And(x, y, 1)) @SKIP("abstract class") def test_sympy__logic__boolalg__Boolean(): pass def test_sympy__logic__boolalg__BooleanFunction(): from sympy.logic.boolalg import BooleanFunction assert _test_args(BooleanFunction(1, 2, 3)) @SKIP("abstract class") def test_sympy__logic__boolalg__BooleanAtom(): pass def test_sympy__logic__boolalg__BooleanTrue(): from sympy.logic.boolalg import true assert _test_args(true) def test_sympy__logic__boolalg__BooleanFalse(): from sympy.logic.boolalg import false assert _test_args(false) def test_sympy__logic__boolalg__Equivalent(): from sympy.logic.boolalg import Equivalent assert _test_args(Equivalent(x, 2)) def test_sympy__logic__boolalg__ITE(): from sympy.logic.boolalg import ITE assert _test_args(ITE(x, y, 1)) def test_sympy__logic__boolalg__Implies(): from sympy.logic.boolalg import Implies assert _test_args(Implies(x, y)) def test_sympy__logic__boolalg__Nand(): from sympy.logic.boolalg import Nand assert _test_args(Nand(x, y, 1)) def test_sympy__logic__boolalg__Nor(): from sympy.logic.boolalg import Nor assert _test_args(Nor(x, y)) def test_sympy__logic__boolalg__Not(): from sympy.logic.boolalg import Not assert _test_args(Not(x)) def test_sympy__logic__boolalg__Or(): from sympy.logic.boolalg import Or assert _test_args(Or(x, y)) def test_sympy__logic__boolalg__Xor(): from sympy.logic.boolalg import Xor assert _test_args(Xor(x, y, 2)) def test_sympy__logic__boolalg__Xnor(): from sympy.logic.boolalg import Xnor assert _test_args(Xnor(x, y, 2)) def test_sympy__logic__boolalg__Exclusive(): from sympy.logic.boolalg import Exclusive assert _test_args(Exclusive(x, y, z)) def test_sympy__matrices__matrices__DeferredVector(): from sympy.matrices.matrices import DeferredVector assert _test_args(DeferredVector("X")) @SKIP("abstract class") def test_sympy__matrices__expressions__matexpr__MatrixBase(): pass def test_sympy__matrices__immutable__ImmutableDenseMatrix(): from sympy.matrices.immutable import ImmutableDenseMatrix m = ImmutableDenseMatrix([[1, 2], [3, 4]]) assert _test_args(m) assert _test_args(Basic(*list(m))) m = ImmutableDenseMatrix(1, 1, [1]) assert _test_args(m) assert _test_args(Basic(*list(m))) m = ImmutableDenseMatrix(2, 2, lambda i, j: 1) assert m[0, 0] is S.One m = ImmutableDenseMatrix(2, 2, lambda i, j: 1/(1 + i) + 1/(1 + j)) assert m[1, 1] is S.One # true div. will give 1.0 if i,j not sympified assert _test_args(m) assert _test_args(Basic(*list(m))) def test_sympy__matrices__immutable__ImmutableSparseMatrix(): from sympy.matrices.immutable import ImmutableSparseMatrix m = ImmutableSparseMatrix([[1, 2], [3, 4]]) assert _test_args(m) assert _test_args(Basic(*list(m))) m = ImmutableSparseMatrix(1, 1, {(0, 0): 1}) assert _test_args(m) assert _test_args(Basic(*list(m))) m = ImmutableSparseMatrix(1, 1, [1]) assert _test_args(m) assert _test_args(Basic(*list(m))) m = ImmutableSparseMatrix(2, 2, lambda i, j: 1) assert m[0, 0] is S.One m = ImmutableSparseMatrix(2, 2, lambda i, j: 1/(1 + i) + 1/(1 + j)) assert m[1, 1] is S.One # true div. will give 1.0 if i,j not sympified assert _test_args(m) assert _test_args(Basic(*list(m))) def test_sympy__matrices__expressions__slice__MatrixSlice(): from sympy.matrices.expressions.slice import MatrixSlice from sympy.matrices.expressions import MatrixSymbol X = MatrixSymbol('X', 4, 4) assert _test_args(MatrixSlice(X, (0, 2), (0, 2))) def test_sympy__matrices__expressions__applyfunc__ElementwiseApplyFunction(): from sympy.matrices.expressions.applyfunc import ElementwiseApplyFunction from sympy.matrices.expressions import MatrixSymbol X = MatrixSymbol("X", x, x) func = Lambda(x, x**2) assert _test_args(ElementwiseApplyFunction(func, X)) def test_sympy__matrices__expressions__blockmatrix__BlockDiagMatrix(): from sympy.matrices.expressions.blockmatrix import BlockDiagMatrix from sympy.matrices.expressions import MatrixSymbol X = MatrixSymbol('X', x, x) Y = MatrixSymbol('Y', y, y) assert _test_args(BlockDiagMatrix(X, Y)) def test_sympy__matrices__expressions__blockmatrix__BlockMatrix(): from sympy.matrices.expressions.blockmatrix import BlockMatrix from sympy.matrices.expressions import MatrixSymbol, ZeroMatrix X = MatrixSymbol('X', x, x) Y = MatrixSymbol('Y', y, y) Z = MatrixSymbol('Z', x, y) O = ZeroMatrix(y, x) assert _test_args(BlockMatrix([[X, Z], [O, Y]])) def test_sympy__matrices__expressions__inverse__Inverse(): from sympy.matrices.expressions.inverse import Inverse from sympy.matrices.expressions import MatrixSymbol assert _test_args(Inverse(MatrixSymbol('A', 3, 3))) def test_sympy__matrices__expressions__matadd__MatAdd(): from sympy.matrices.expressions.matadd import MatAdd from sympy.matrices.expressions import MatrixSymbol X = MatrixSymbol('X', x, y) Y = MatrixSymbol('Y', x, y) assert _test_args(MatAdd(X, Y)) @SKIP("abstract class") def test_sympy__matrices__expressions__matexpr__MatrixExpr(): pass def test_sympy__matrices__expressions__matexpr__MatrixElement(): from sympy.matrices.expressions.matexpr import MatrixSymbol, MatrixElement from sympy import S assert _test_args(MatrixElement(MatrixSymbol('A', 3, 5), S(2), S(3))) def test_sympy__matrices__expressions__matexpr__MatrixSymbol(): from sympy.matrices.expressions.matexpr import MatrixSymbol assert _test_args(MatrixSymbol('A', 3, 5)) def test_sympy__matrices__expressions__special__OneMatrix(): from sympy.matrices.expressions.special import OneMatrix assert _test_args(OneMatrix(3, 5)) def test_sympy__matrices__expressions__special__ZeroMatrix(): from sympy.matrices.expressions.special import ZeroMatrix assert _test_args(ZeroMatrix(3, 5)) def test_sympy__matrices__expressions__special__GenericZeroMatrix(): from sympy.matrices.expressions.special import GenericZeroMatrix assert _test_args(GenericZeroMatrix()) def test_sympy__matrices__expressions__special__Identity(): from sympy.matrices.expressions.special import Identity assert _test_args(Identity(3)) def test_sympy__matrices__expressions__special__GenericIdentity(): from sympy.matrices.expressions.special import GenericIdentity assert _test_args(GenericIdentity()) def test_sympy__matrices__expressions__sets__MatrixSet(): from sympy.matrices.expressions.sets import MatrixSet from sympy import S assert _test_args(MatrixSet(2, 2, S.Reals)) def test_sympy__matrices__expressions__matmul__MatMul(): from sympy.matrices.expressions.matmul import MatMul from sympy.matrices.expressions import MatrixSymbol X = MatrixSymbol('X', x, y) Y = MatrixSymbol('Y', y, x) assert _test_args(MatMul(X, Y)) def test_sympy__matrices__expressions__dotproduct__DotProduct(): from sympy.matrices.expressions.dotproduct import DotProduct from sympy.matrices.expressions import MatrixSymbol X = MatrixSymbol('X', x, 1) Y = MatrixSymbol('Y', x, 1) assert _test_args(DotProduct(X, Y)) def test_sympy__matrices__expressions__diagonal__DiagonalMatrix(): from sympy.matrices.expressions.diagonal import DiagonalMatrix from sympy.matrices.expressions import MatrixSymbol x = MatrixSymbol('x', 10, 1) assert _test_args(DiagonalMatrix(x)) def test_sympy__matrices__expressions__diagonal__DiagonalOf(): from sympy.matrices.expressions.diagonal import DiagonalOf from sympy.matrices.expressions import MatrixSymbol X = MatrixSymbol('x', 10, 10) assert _test_args(DiagonalOf(X)) def test_sympy__matrices__expressions__diagonal__DiagMatrix(): from sympy.matrices.expressions.diagonal import DiagMatrix from sympy.matrices.expressions import MatrixSymbol x = MatrixSymbol('x', 10, 1) assert _test_args(DiagMatrix(x)) def test_sympy__matrices__expressions__hadamard__HadamardProduct(): from sympy.matrices.expressions.hadamard import HadamardProduct from sympy.matrices.expressions import MatrixSymbol X = MatrixSymbol('X', x, y) Y = MatrixSymbol('Y', x, y) assert _test_args(HadamardProduct(X, Y)) def test_sympy__matrices__expressions__hadamard__HadamardPower(): from sympy.matrices.expressions.hadamard import HadamardPower from sympy.matrices.expressions import MatrixSymbol from sympy import Symbol X = MatrixSymbol('X', x, y) n = Symbol("n") assert _test_args(HadamardPower(X, n)) def test_sympy__matrices__expressions__kronecker__KroneckerProduct(): from sympy.matrices.expressions.kronecker import KroneckerProduct from sympy.matrices.expressions import MatrixSymbol X = MatrixSymbol('X', x, y) Y = MatrixSymbol('Y', x, y) assert _test_args(KroneckerProduct(X, Y)) def test_sympy__matrices__expressions__matpow__MatPow(): from sympy.matrices.expressions.matpow import MatPow from sympy.matrices.expressions import MatrixSymbol X = MatrixSymbol('X', x, x) assert _test_args(MatPow(X, 2)) def test_sympy__matrices__expressions__transpose__Transpose(): from sympy.matrices.expressions.transpose import Transpose from sympy.matrices.expressions import MatrixSymbol assert _test_args(Transpose(MatrixSymbol('A', 3, 5))) def test_sympy__matrices__expressions__adjoint__Adjoint(): from sympy.matrices.expressions.adjoint import Adjoint from sympy.matrices.expressions import MatrixSymbol assert _test_args(Adjoint(MatrixSymbol('A', 3, 5))) def test_sympy__matrices__expressions__trace__Trace(): from sympy.matrices.expressions.trace import Trace from sympy.matrices.expressions import MatrixSymbol assert _test_args(Trace(MatrixSymbol('A', 3, 3))) def test_sympy__matrices__expressions__determinant__Determinant(): from sympy.matrices.expressions.determinant import Determinant from sympy.matrices.expressions import MatrixSymbol assert _test_args(Determinant(MatrixSymbol('A', 3, 3))) def test_sympy__matrices__expressions__determinant__Permanent(): from sympy.matrices.expressions.determinant import Permanent from sympy.matrices.expressions import MatrixSymbol assert _test_args(Permanent(MatrixSymbol('A', 3, 4))) def test_sympy__matrices__expressions__funcmatrix__FunctionMatrix(): from sympy.matrices.expressions.funcmatrix import FunctionMatrix from sympy import symbols i, j = symbols('i,j') assert _test_args(FunctionMatrix(3, 3, Lambda((i, j), i - j) )) def test_sympy__matrices__expressions__fourier__DFT(): from sympy.matrices.expressions.fourier import DFT from sympy import S assert _test_args(DFT(S(2))) def test_sympy__matrices__expressions__fourier__IDFT(): from sympy.matrices.expressions.fourier import IDFT from sympy import S assert _test_args(IDFT(S(2))) from sympy.matrices.expressions import MatrixSymbol X = MatrixSymbol('X', 10, 10) def test_sympy__matrices__expressions__factorizations__LofLU(): from sympy.matrices.expressions.factorizations import LofLU assert _test_args(LofLU(X)) def test_sympy__matrices__expressions__factorizations__UofLU(): from sympy.matrices.expressions.factorizations import UofLU assert _test_args(UofLU(X)) def test_sympy__matrices__expressions__factorizations__QofQR(): from sympy.matrices.expressions.factorizations import QofQR assert _test_args(QofQR(X)) def test_sympy__matrices__expressions__factorizations__RofQR(): from sympy.matrices.expressions.factorizations import RofQR assert _test_args(RofQR(X)) def test_sympy__matrices__expressions__factorizations__LofCholesky(): from sympy.matrices.expressions.factorizations import LofCholesky assert _test_args(LofCholesky(X)) def test_sympy__matrices__expressions__factorizations__UofCholesky(): from sympy.matrices.expressions.factorizations import UofCholesky assert _test_args(UofCholesky(X)) def test_sympy__matrices__expressions__factorizations__EigenVectors(): from sympy.matrices.expressions.factorizations import EigenVectors assert _test_args(EigenVectors(X)) def test_sympy__matrices__expressions__factorizations__EigenValues(): from sympy.matrices.expressions.factorizations import EigenValues assert _test_args(EigenValues(X)) def test_sympy__matrices__expressions__factorizations__UofSVD(): from sympy.matrices.expressions.factorizations import UofSVD assert _test_args(UofSVD(X)) def test_sympy__matrices__expressions__factorizations__VofSVD(): from sympy.matrices.expressions.factorizations import VofSVD assert _test_args(VofSVD(X)) def test_sympy__matrices__expressions__factorizations__SofSVD(): from sympy.matrices.expressions.factorizations import SofSVD assert _test_args(SofSVD(X)) @SKIP("abstract class") def test_sympy__matrices__expressions__factorizations__Factorization(): pass def test_sympy__matrices__expressions__permutation__PermutationMatrix(): from sympy.combinatorics import Permutation from sympy.matrices.expressions.permutation import PermutationMatrix assert _test_args(PermutationMatrix(Permutation([2, 0, 1]))) def test_sympy__matrices__expressions__permutation__MatrixPermute(): from sympy.combinatorics import Permutation from sympy.matrices.expressions.matexpr import MatrixSymbol from sympy.matrices.expressions.permutation import MatrixPermute A = MatrixSymbol('A', 3, 3) assert _test_args(MatrixPermute(A, Permutation([2, 0, 1]))) def test_sympy__matrices__expressions__companion__CompanionMatrix(): from sympy.core.symbol import Symbol from sympy.matrices.expressions.companion import CompanionMatrix from sympy.polys.polytools import Poly x = Symbol('x') p = Poly([1, 2, 3], x) assert _test_args(CompanionMatrix(p)) def test_sympy__physics__vector__frame__CoordinateSym(): from sympy.physics.vector import CoordinateSym from sympy.physics.vector import ReferenceFrame assert _test_args(CoordinateSym('R_x', ReferenceFrame('R'), 0)) def test_sympy__physics__paulialgebra__Pauli(): from sympy.physics.paulialgebra import Pauli assert _test_args(Pauli(1)) def test_sympy__physics__quantum__anticommutator__AntiCommutator(): from sympy.physics.quantum.anticommutator import AntiCommutator assert _test_args(AntiCommutator(x, y)) def test_sympy__physics__quantum__cartesian__PositionBra3D(): from sympy.physics.quantum.cartesian import PositionBra3D assert _test_args(PositionBra3D(x, y, z)) def test_sympy__physics__quantum__cartesian__PositionKet3D(): from sympy.physics.quantum.cartesian import PositionKet3D assert _test_args(PositionKet3D(x, y, z)) def test_sympy__physics__quantum__cartesian__PositionState3D(): from sympy.physics.quantum.cartesian import PositionState3D assert _test_args(PositionState3D(x, y, z)) def test_sympy__physics__quantum__cartesian__PxBra(): from sympy.physics.quantum.cartesian import PxBra assert _test_args(PxBra(x, y, z)) def test_sympy__physics__quantum__cartesian__PxKet(): from sympy.physics.quantum.cartesian import PxKet assert _test_args(PxKet(x, y, z)) def test_sympy__physics__quantum__cartesian__PxOp(): from sympy.physics.quantum.cartesian import PxOp assert _test_args(PxOp(x, y, z)) def test_sympy__physics__quantum__cartesian__XBra(): from sympy.physics.quantum.cartesian import XBra assert _test_args(XBra(x)) def test_sympy__physics__quantum__cartesian__XKet(): from sympy.physics.quantum.cartesian import XKet assert _test_args(XKet(x)) def test_sympy__physics__quantum__cartesian__XOp(): from sympy.physics.quantum.cartesian import XOp assert _test_args(XOp(x)) def test_sympy__physics__quantum__cartesian__YOp(): from sympy.physics.quantum.cartesian import YOp assert _test_args(YOp(x)) def test_sympy__physics__quantum__cartesian__ZOp(): from sympy.physics.quantum.cartesian import ZOp assert _test_args(ZOp(x)) def test_sympy__physics__quantum__cg__CG(): from sympy.physics.quantum.cg import CG from sympy import S assert _test_args(CG(Rational(3, 2), Rational(3, 2), S.Half, Rational(-1, 2), 1, 1)) def test_sympy__physics__quantum__cg__Wigner3j(): from sympy.physics.quantum.cg import Wigner3j assert _test_args(Wigner3j(6, 0, 4, 0, 2, 0)) def test_sympy__physics__quantum__cg__Wigner6j(): from sympy.physics.quantum.cg import Wigner6j assert _test_args(Wigner6j(1, 2, 3, 2, 1, 2)) def test_sympy__physics__quantum__cg__Wigner9j(): from sympy.physics.quantum.cg import Wigner9j assert _test_args(Wigner9j(2, 1, 1, Rational(3, 2), S.Half, 1, S.Half, S.Half, 0)) def test_sympy__physics__quantum__circuitplot__Mz(): from sympy.physics.quantum.circuitplot import Mz assert _test_args(Mz(0)) def test_sympy__physics__quantum__circuitplot__Mx(): from sympy.physics.quantum.circuitplot import Mx assert _test_args(Mx(0)) def test_sympy__physics__quantum__commutator__Commutator(): from sympy.physics.quantum.commutator import Commutator A, B = symbols('A,B', commutative=False) assert _test_args(Commutator(A, B)) def test_sympy__physics__quantum__constants__HBar(): from sympy.physics.quantum.constants import HBar assert _test_args(HBar()) def test_sympy__physics__quantum__dagger__Dagger(): from sympy.physics.quantum.dagger import Dagger from sympy.physics.quantum.state import Ket assert _test_args(Dagger(Dagger(Ket('psi')))) def test_sympy__physics__quantum__gate__CGate(): from sympy.physics.quantum.gate import CGate, Gate assert _test_args(CGate((0, 1), Gate(2))) def test_sympy__physics__quantum__gate__CGateS(): from sympy.physics.quantum.gate import CGateS, Gate assert _test_args(CGateS((0, 1), Gate(2))) def test_sympy__physics__quantum__gate__CNotGate(): from sympy.physics.quantum.gate import CNotGate assert _test_args(CNotGate(0, 1)) def test_sympy__physics__quantum__gate__Gate(): from sympy.physics.quantum.gate import Gate assert _test_args(Gate(0)) def test_sympy__physics__quantum__gate__HadamardGate(): from sympy.physics.quantum.gate import HadamardGate assert _test_args(HadamardGate(0)) def test_sympy__physics__quantum__gate__IdentityGate(): from sympy.physics.quantum.gate import IdentityGate assert _test_args(IdentityGate(0)) def test_sympy__physics__quantum__gate__OneQubitGate(): from sympy.physics.quantum.gate import OneQubitGate assert _test_args(OneQubitGate(0)) def test_sympy__physics__quantum__gate__PhaseGate(): from sympy.physics.quantum.gate import PhaseGate assert _test_args(PhaseGate(0)) def test_sympy__physics__quantum__gate__SwapGate(): from sympy.physics.quantum.gate import SwapGate assert _test_args(SwapGate(0, 1)) def test_sympy__physics__quantum__gate__TGate(): from sympy.physics.quantum.gate import TGate assert _test_args(TGate(0)) def test_sympy__physics__quantum__gate__TwoQubitGate(): from sympy.physics.quantum.gate import TwoQubitGate assert _test_args(TwoQubitGate(0)) def test_sympy__physics__quantum__gate__UGate(): from sympy.physics.quantum.gate import UGate from sympy.matrices.immutable import ImmutableDenseMatrix from sympy import Integer, Tuple assert _test_args( UGate(Tuple(Integer(1)), ImmutableDenseMatrix([[1, 0], [0, 2]]))) def test_sympy__physics__quantum__gate__XGate(): from sympy.physics.quantum.gate import XGate assert _test_args(XGate(0)) def test_sympy__physics__quantum__gate__YGate(): from sympy.physics.quantum.gate import YGate assert _test_args(YGate(0)) def test_sympy__physics__quantum__gate__ZGate(): from sympy.physics.quantum.gate import ZGate assert _test_args(ZGate(0)) @SKIP("TODO: sympy.physics") def test_sympy__physics__quantum__grover__OracleGate(): from sympy.physics.quantum.grover import OracleGate assert _test_args(OracleGate()) def test_sympy__physics__quantum__grover__WGate(): from sympy.physics.quantum.grover import WGate assert _test_args(WGate(1)) def test_sympy__physics__quantum__hilbert__ComplexSpace(): from sympy.physics.quantum.hilbert import ComplexSpace assert _test_args(ComplexSpace(x)) def test_sympy__physics__quantum__hilbert__DirectSumHilbertSpace(): from sympy.physics.quantum.hilbert import DirectSumHilbertSpace, ComplexSpace, FockSpace c = ComplexSpace(2) f = FockSpace() assert _test_args(DirectSumHilbertSpace(c, f)) def test_sympy__physics__quantum__hilbert__FockSpace(): from sympy.physics.quantum.hilbert import FockSpace assert _test_args(FockSpace()) def test_sympy__physics__quantum__hilbert__HilbertSpace(): from sympy.physics.quantum.hilbert import HilbertSpace assert _test_args(HilbertSpace()) def test_sympy__physics__quantum__hilbert__L2(): from sympy.physics.quantum.hilbert import L2 from sympy import oo, Interval assert _test_args(L2(Interval(0, oo))) def test_sympy__physics__quantum__hilbert__TensorPowerHilbertSpace(): from sympy.physics.quantum.hilbert import TensorPowerHilbertSpace, FockSpace f = FockSpace() assert _test_args(TensorPowerHilbertSpace(f, 2)) def test_sympy__physics__quantum__hilbert__TensorProductHilbertSpace(): from sympy.physics.quantum.hilbert import TensorProductHilbertSpace, FockSpace, ComplexSpace c = ComplexSpace(2) f = FockSpace() assert _test_args(TensorProductHilbertSpace(f, c)) def test_sympy__physics__quantum__innerproduct__InnerProduct(): from sympy.physics.quantum import Bra, Ket, InnerProduct b = Bra('b') k = Ket('k') assert _test_args(InnerProduct(b, k)) def test_sympy__physics__quantum__operator__DifferentialOperator(): from sympy.physics.quantum.operator import DifferentialOperator from sympy import Derivative, Function f = Function('f') assert _test_args(DifferentialOperator(1/x*Derivative(f(x), x), f(x))) def test_sympy__physics__quantum__operator__HermitianOperator(): from sympy.physics.quantum.operator import HermitianOperator assert _test_args(HermitianOperator('H')) def test_sympy__physics__quantum__operator__IdentityOperator(): from sympy.physics.quantum.operator import IdentityOperator assert _test_args(IdentityOperator(5)) def test_sympy__physics__quantum__operator__Operator(): from sympy.physics.quantum.operator import Operator assert _test_args(Operator('A')) def test_sympy__physics__quantum__operator__OuterProduct(): from sympy.physics.quantum.operator import OuterProduct from sympy.physics.quantum import Ket, Bra b = Bra('b') k = Ket('k') assert _test_args(OuterProduct(k, b)) def test_sympy__physics__quantum__operator__UnitaryOperator(): from sympy.physics.quantum.operator import UnitaryOperator assert _test_args(UnitaryOperator('U')) def test_sympy__physics__quantum__piab__PIABBra(): from sympy.physics.quantum.piab import PIABBra assert _test_args(PIABBra('B')) def test_sympy__physics__quantum__boson__BosonOp(): from sympy.physics.quantum.boson import BosonOp assert _test_args(BosonOp('a')) assert _test_args(BosonOp('a', False)) def test_sympy__physics__quantum__boson__BosonFockKet(): from sympy.physics.quantum.boson import BosonFockKet assert _test_args(BosonFockKet(1)) def test_sympy__physics__quantum__boson__BosonFockBra(): from sympy.physics.quantum.boson import BosonFockBra assert _test_args(BosonFockBra(1)) def test_sympy__physics__quantum__boson__BosonCoherentKet(): from sympy.physics.quantum.boson import BosonCoherentKet assert _test_args(BosonCoherentKet(1)) def test_sympy__physics__quantum__boson__BosonCoherentBra(): from sympy.physics.quantum.boson import BosonCoherentBra assert _test_args(BosonCoherentBra(1)) def test_sympy__physics__quantum__fermion__FermionOp(): from sympy.physics.quantum.fermion import FermionOp assert _test_args(FermionOp('c')) assert _test_args(FermionOp('c', False)) def test_sympy__physics__quantum__fermion__FermionFockKet(): from sympy.physics.quantum.fermion import FermionFockKet assert _test_args(FermionFockKet(1)) def test_sympy__physics__quantum__fermion__FermionFockBra(): from sympy.physics.quantum.fermion import FermionFockBra assert _test_args(FermionFockBra(1)) def test_sympy__physics__quantum__pauli__SigmaOpBase(): from sympy.physics.quantum.pauli import SigmaOpBase assert _test_args(SigmaOpBase()) def test_sympy__physics__quantum__pauli__SigmaX(): from sympy.physics.quantum.pauli import SigmaX assert _test_args(SigmaX()) def test_sympy__physics__quantum__pauli__SigmaY(): from sympy.physics.quantum.pauli import SigmaY assert _test_args(SigmaY()) def test_sympy__physics__quantum__pauli__SigmaZ(): from sympy.physics.quantum.pauli import SigmaZ assert _test_args(SigmaZ()) def test_sympy__physics__quantum__pauli__SigmaMinus(): from sympy.physics.quantum.pauli import SigmaMinus assert _test_args(SigmaMinus()) def test_sympy__physics__quantum__pauli__SigmaPlus(): from sympy.physics.quantum.pauli import SigmaPlus assert _test_args(SigmaPlus()) def test_sympy__physics__quantum__pauli__SigmaZKet(): from sympy.physics.quantum.pauli import SigmaZKet assert _test_args(SigmaZKet(0)) def test_sympy__physics__quantum__pauli__SigmaZBra(): from sympy.physics.quantum.pauli import SigmaZBra assert _test_args(SigmaZBra(0)) def test_sympy__physics__quantum__piab__PIABHamiltonian(): from sympy.physics.quantum.piab import PIABHamiltonian assert _test_args(PIABHamiltonian('P')) def test_sympy__physics__quantum__piab__PIABKet(): from sympy.physics.quantum.piab import PIABKet assert _test_args(PIABKet('K')) def test_sympy__physics__quantum__qexpr__QExpr(): from sympy.physics.quantum.qexpr import QExpr assert _test_args(QExpr(0)) def test_sympy__physics__quantum__qft__Fourier(): from sympy.physics.quantum.qft import Fourier assert _test_args(Fourier(0, 1)) def test_sympy__physics__quantum__qft__IQFT(): from sympy.physics.quantum.qft import IQFT assert _test_args(IQFT(0, 1)) def test_sympy__physics__quantum__qft__QFT(): from sympy.physics.quantum.qft import QFT assert _test_args(QFT(0, 1)) def test_sympy__physics__quantum__qft__RkGate(): from sympy.physics.quantum.qft import RkGate assert _test_args(RkGate(0, 1)) def test_sympy__physics__quantum__qubit__IntQubit(): from sympy.physics.quantum.qubit import IntQubit assert _test_args(IntQubit(0)) def test_sympy__physics__quantum__qubit__IntQubitBra(): from sympy.physics.quantum.qubit import IntQubitBra assert _test_args(IntQubitBra(0)) def test_sympy__physics__quantum__qubit__IntQubitState(): from sympy.physics.quantum.qubit import IntQubitState, QubitState assert _test_args(IntQubitState(QubitState(0, 1))) def test_sympy__physics__quantum__qubit__Qubit(): from sympy.physics.quantum.qubit import Qubit assert _test_args(Qubit(0, 0, 0)) def test_sympy__physics__quantum__qubit__QubitBra(): from sympy.physics.quantum.qubit import QubitBra assert _test_args(QubitBra('1', 0)) def test_sympy__physics__quantum__qubit__QubitState(): from sympy.physics.quantum.qubit import QubitState assert _test_args(QubitState(0, 1)) def test_sympy__physics__quantum__density__Density(): from sympy.physics.quantum.density import Density from sympy.physics.quantum.state import Ket assert _test_args(Density([Ket(0), 0.5], [Ket(1), 0.5])) @SKIP("TODO: sympy.physics.quantum.shor: Cmod Not Implemented") def test_sympy__physics__quantum__shor__CMod(): from sympy.physics.quantum.shor import CMod assert _test_args(CMod()) def test_sympy__physics__quantum__spin__CoupledSpinState(): from sympy.physics.quantum.spin import CoupledSpinState assert _test_args(CoupledSpinState(1, 0, (1, 1))) assert _test_args(CoupledSpinState(1, 0, (1, S.Half, S.Half))) assert _test_args(CoupledSpinState( 1, 0, (1, S.Half, S.Half), ((2, 3, S.Half), (1, 2, 1)) )) j, m, j1, j2, j3, j12, x = symbols('j m j1:4 j12 x') assert CoupledSpinState( j, m, (j1, j2, j3)).subs(j2, x) == CoupledSpinState(j, m, (j1, x, j3)) assert CoupledSpinState(j, m, (j1, j2, j3), ((1, 3, j12), (1, 2, j)) ).subs(j12, x) == \ CoupledSpinState(j, m, (j1, j2, j3), ((1, 3, x), (1, 2, j)) ) def test_sympy__physics__quantum__spin__J2Op(): from sympy.physics.quantum.spin import J2Op assert _test_args(J2Op('J')) def test_sympy__physics__quantum__spin__JminusOp(): from sympy.physics.quantum.spin import JminusOp assert _test_args(JminusOp('J')) def test_sympy__physics__quantum__spin__JplusOp(): from sympy.physics.quantum.spin import JplusOp assert _test_args(JplusOp('J')) def test_sympy__physics__quantum__spin__JxBra(): from sympy.physics.quantum.spin import JxBra assert _test_args(JxBra(1, 0)) def test_sympy__physics__quantum__spin__JxBraCoupled(): from sympy.physics.quantum.spin import JxBraCoupled assert _test_args(JxBraCoupled(1, 0, (1, 1))) def test_sympy__physics__quantum__spin__JxKet(): from sympy.physics.quantum.spin import JxKet assert _test_args(JxKet(1, 0)) def test_sympy__physics__quantum__spin__JxKetCoupled(): from sympy.physics.quantum.spin import JxKetCoupled assert _test_args(JxKetCoupled(1, 0, (1, 1))) def test_sympy__physics__quantum__spin__JxOp(): from sympy.physics.quantum.spin import JxOp assert _test_args(JxOp('J')) def test_sympy__physics__quantum__spin__JyBra(): from sympy.physics.quantum.spin import JyBra assert _test_args(JyBra(1, 0)) def test_sympy__physics__quantum__spin__JyBraCoupled(): from sympy.physics.quantum.spin import JyBraCoupled assert _test_args(JyBraCoupled(1, 0, (1, 1))) def test_sympy__physics__quantum__spin__JyKet(): from sympy.physics.quantum.spin import JyKet assert _test_args(JyKet(1, 0)) def test_sympy__physics__quantum__spin__JyKetCoupled(): from sympy.physics.quantum.spin import JyKetCoupled assert _test_args(JyKetCoupled(1, 0, (1, 1))) def test_sympy__physics__quantum__spin__JyOp(): from sympy.physics.quantum.spin import JyOp assert _test_args(JyOp('J')) def test_sympy__physics__quantum__spin__JzBra(): from sympy.physics.quantum.spin import JzBra assert _test_args(JzBra(1, 0)) def test_sympy__physics__quantum__spin__JzBraCoupled(): from sympy.physics.quantum.spin import JzBraCoupled assert _test_args(JzBraCoupled(1, 0, (1, 1))) def test_sympy__physics__quantum__spin__JzKet(): from sympy.physics.quantum.spin import JzKet assert _test_args(JzKet(1, 0)) def test_sympy__physics__quantum__spin__JzKetCoupled(): from sympy.physics.quantum.spin import JzKetCoupled assert _test_args(JzKetCoupled(1, 0, (1, 1))) def test_sympy__physics__quantum__spin__JzOp(): from sympy.physics.quantum.spin import JzOp assert _test_args(JzOp('J')) def test_sympy__physics__quantum__spin__Rotation(): from sympy.physics.quantum.spin import Rotation assert _test_args(Rotation(pi, 0, pi/2)) def test_sympy__physics__quantum__spin__SpinState(): from sympy.physics.quantum.spin import SpinState assert _test_args(SpinState(1, 0)) def test_sympy__physics__quantum__spin__WignerD(): from sympy.physics.quantum.spin import WignerD assert _test_args(WignerD(0, 1, 2, 3, 4, 5)) def test_sympy__physics__quantum__state__Bra(): from sympy.physics.quantum.state import Bra assert _test_args(Bra(0)) def test_sympy__physics__quantum__state__BraBase(): from sympy.physics.quantum.state import BraBase assert _test_args(BraBase(0)) def test_sympy__physics__quantum__state__Ket(): from sympy.physics.quantum.state import Ket assert _test_args(Ket(0)) def test_sympy__physics__quantum__state__KetBase(): from sympy.physics.quantum.state import KetBase assert _test_args(KetBase(0)) def test_sympy__physics__quantum__state__State(): from sympy.physics.quantum.state import State assert _test_args(State(0)) def test_sympy__physics__quantum__state__StateBase(): from sympy.physics.quantum.state import StateBase assert _test_args(StateBase(0)) def test_sympy__physics__quantum__state__OrthogonalBra(): from sympy.physics.quantum.state import OrthogonalBra assert _test_args(OrthogonalBra(0)) def test_sympy__physics__quantum__state__OrthogonalKet(): from sympy.physics.quantum.state import OrthogonalKet assert _test_args(OrthogonalKet(0)) def test_sympy__physics__quantum__state__OrthogonalState(): from sympy.physics.quantum.state import OrthogonalState assert _test_args(OrthogonalState(0)) def test_sympy__physics__quantum__state__TimeDepBra(): from sympy.physics.quantum.state import TimeDepBra assert _test_args(TimeDepBra('psi', 't')) def test_sympy__physics__quantum__state__TimeDepKet(): from sympy.physics.quantum.state import TimeDepKet assert _test_args(TimeDepKet('psi', 't')) def test_sympy__physics__quantum__state__TimeDepState(): from sympy.physics.quantum.state import TimeDepState assert _test_args(TimeDepState('psi', 't')) def test_sympy__physics__quantum__state__Wavefunction(): from sympy.physics.quantum.state import Wavefunction from sympy.functions import sin from sympy import Piecewise n = 1 L = 1 g = Piecewise((0, x < 0), (0, x > L), (sqrt(2//L)*sin(n*pi*x/L), True)) assert _test_args(Wavefunction(g, x)) def test_sympy__physics__quantum__tensorproduct__TensorProduct(): from sympy.physics.quantum.tensorproduct import TensorProduct assert _test_args(TensorProduct(x, y)) def test_sympy__physics__quantum__identitysearch__GateIdentity(): from sympy.physics.quantum.gate import X from sympy.physics.quantum.identitysearch import GateIdentity assert _test_args(GateIdentity(X(0), X(0))) def test_sympy__physics__quantum__sho1d__SHOOp(): from sympy.physics.quantum.sho1d import SHOOp assert _test_args(SHOOp('a')) def test_sympy__physics__quantum__sho1d__RaisingOp(): from sympy.physics.quantum.sho1d import RaisingOp assert _test_args(RaisingOp('a')) def test_sympy__physics__quantum__sho1d__LoweringOp(): from sympy.physics.quantum.sho1d import LoweringOp assert _test_args(LoweringOp('a')) def test_sympy__physics__quantum__sho1d__NumberOp(): from sympy.physics.quantum.sho1d import NumberOp assert _test_args(NumberOp('N')) def test_sympy__physics__quantum__sho1d__Hamiltonian(): from sympy.physics.quantum.sho1d import Hamiltonian assert _test_args(Hamiltonian('H')) def test_sympy__physics__quantum__sho1d__SHOState(): from sympy.physics.quantum.sho1d import SHOState assert _test_args(SHOState(0)) def test_sympy__physics__quantum__sho1d__SHOKet(): from sympy.physics.quantum.sho1d import SHOKet assert _test_args(SHOKet(0)) def test_sympy__physics__quantum__sho1d__SHOBra(): from sympy.physics.quantum.sho1d import SHOBra assert _test_args(SHOBra(0)) def test_sympy__physics__secondquant__AnnihilateBoson(): from sympy.physics.secondquant import AnnihilateBoson assert _test_args(AnnihilateBoson(0)) def test_sympy__physics__secondquant__AnnihilateFermion(): from sympy.physics.secondquant import AnnihilateFermion assert _test_args(AnnihilateFermion(0)) @SKIP("abstract class") def test_sympy__physics__secondquant__Annihilator(): pass def test_sympy__physics__secondquant__AntiSymmetricTensor(): from sympy.physics.secondquant import AntiSymmetricTensor i, j = symbols('i j', below_fermi=True) a, b = symbols('a b', above_fermi=True) assert _test_args(AntiSymmetricTensor('v', (a, i), (b, j))) def test_sympy__physics__secondquant__BosonState(): from sympy.physics.secondquant import BosonState assert _test_args(BosonState((0, 1))) @SKIP("abstract class") def test_sympy__physics__secondquant__BosonicOperator(): pass def test_sympy__physics__secondquant__Commutator(): from sympy.physics.secondquant import Commutator assert _test_args(Commutator(x, y)) def test_sympy__physics__secondquant__CreateBoson(): from sympy.physics.secondquant import CreateBoson assert _test_args(CreateBoson(0)) def test_sympy__physics__secondquant__CreateFermion(): from sympy.physics.secondquant import CreateFermion assert _test_args(CreateFermion(0)) @SKIP("abstract class") def test_sympy__physics__secondquant__Creator(): pass def test_sympy__physics__secondquant__Dagger(): from sympy.physics.secondquant import Dagger from sympy import I assert _test_args(Dagger(2*I)) def test_sympy__physics__secondquant__FermionState(): from sympy.physics.secondquant import FermionState assert _test_args(FermionState((0, 1))) def test_sympy__physics__secondquant__FermionicOperator(): from sympy.physics.secondquant import FermionicOperator assert _test_args(FermionicOperator(0)) def test_sympy__physics__secondquant__FockState(): from sympy.physics.secondquant import FockState assert _test_args(FockState((0, 1))) def test_sympy__physics__secondquant__FockStateBosonBra(): from sympy.physics.secondquant import FockStateBosonBra assert _test_args(FockStateBosonBra((0, 1))) def test_sympy__physics__secondquant__FockStateBosonKet(): from sympy.physics.secondquant import FockStateBosonKet assert _test_args(FockStateBosonKet((0, 1))) def test_sympy__physics__secondquant__FockStateBra(): from sympy.physics.secondquant import FockStateBra assert _test_args(FockStateBra((0, 1))) def test_sympy__physics__secondquant__FockStateFermionBra(): from sympy.physics.secondquant import FockStateFermionBra assert _test_args(FockStateFermionBra((0, 1))) def test_sympy__physics__secondquant__FockStateFermionKet(): from sympy.physics.secondquant import FockStateFermionKet assert _test_args(FockStateFermionKet((0, 1))) def test_sympy__physics__secondquant__FockStateKet(): from sympy.physics.secondquant import FockStateKet assert _test_args(FockStateKet((0, 1))) def test_sympy__physics__secondquant__InnerProduct(): from sympy.physics.secondquant import InnerProduct from sympy.physics.secondquant import FockStateKet, FockStateBra assert _test_args(InnerProduct(FockStateBra((0, 1)), FockStateKet((0, 1)))) def test_sympy__physics__secondquant__NO(): from sympy.physics.secondquant import NO, F, Fd assert _test_args(NO(Fd(x)*F(y))) def test_sympy__physics__secondquant__PermutationOperator(): from sympy.physics.secondquant import PermutationOperator assert _test_args(PermutationOperator(0, 1)) def test_sympy__physics__secondquant__SqOperator(): from sympy.physics.secondquant import SqOperator assert _test_args(SqOperator(0)) def test_sympy__physics__secondquant__TensorSymbol(): from sympy.physics.secondquant import TensorSymbol assert _test_args(TensorSymbol(x)) def test_sympy__physics__control__lti__TransferFunction(): from sympy.physics.control.lti import TransferFunction assert _test_args(TransferFunction(2, 3, x)) def test_sympy__physics__control__lti__Series(): from sympy.physics.control import Series, TransferFunction tf1 = TransferFunction(x**2 - y**3, y - z, x) tf2 = TransferFunction(y - x, z + y, x) assert _test_args(Series(tf1, tf2)) def test_sympy__physics__control__lti__Parallel(): from sympy.physics.control import Parallel, TransferFunction tf1 = TransferFunction(x**2 - y**3, y - z, x) tf2 = TransferFunction(y - x, z + y, x) assert _test_args(Parallel(tf1, tf2)) def test_sympy__physics__control__lti__Feedback(): from sympy.physics.control import TransferFunction, Feedback tf1 = TransferFunction(x**2 - y**3, y - z, x) tf2 = TransferFunction(y - x, z + y, x) assert _test_args(Feedback(tf1, tf2)) def test_sympy__physics__units__dimensions__Dimension(): from sympy.physics.units.dimensions import Dimension assert _test_args(Dimension("length", "L")) def test_sympy__physics__units__dimensions__DimensionSystem(): from sympy.physics.units.dimensions import DimensionSystem from sympy.physics.units.definitions.dimension_definitions import length, time, velocity assert _test_args(DimensionSystem((length, time), (velocity,))) def test_sympy__physics__units__quantities__Quantity(): from sympy.physics.units.quantities import Quantity assert _test_args(Quantity("dam")) def test_sympy__physics__units__prefixes__Prefix(): from sympy.physics.units.prefixes import Prefix assert _test_args(Prefix('kilo', 'k', 3)) def test_sympy__core__numbers__AlgebraicNumber(): from sympy.core.numbers import AlgebraicNumber assert _test_args(AlgebraicNumber(sqrt(2), [1, 2, 3])) def test_sympy__polys__polytools__GroebnerBasis(): from sympy.polys.polytools import GroebnerBasis assert _test_args(GroebnerBasis([x, y, z], x, y, z)) def test_sympy__polys__polytools__Poly(): from sympy.polys.polytools import Poly assert _test_args(Poly(2, x, y)) def test_sympy__polys__polytools__PurePoly(): from sympy.polys.polytools import PurePoly assert _test_args(PurePoly(2, x, y)) @SKIP('abstract class') def test_sympy__polys__rootoftools__RootOf(): pass def test_sympy__polys__rootoftools__ComplexRootOf(): from sympy.polys.rootoftools import ComplexRootOf assert _test_args(ComplexRootOf(x**3 + x + 1, 0)) def test_sympy__polys__rootoftools__RootSum(): from sympy.polys.rootoftools import RootSum assert _test_args(RootSum(x**3 + x + 1, sin)) def test_sympy__series__limits__Limit(): from sympy.series.limits import Limit assert _test_args(Limit(x, x, 0, dir='-')) def test_sympy__series__order__Order(): from sympy.series.order import Order assert _test_args(Order(1, x, y)) @SKIP('Abstract Class') def test_sympy__series__sequences__SeqBase(): pass def test_sympy__series__sequences__EmptySequence(): # Need to imort the instance from series not the class from # series.sequence from sympy.series import EmptySequence assert _test_args(EmptySequence) @SKIP('Abstract Class') def test_sympy__series__sequences__SeqExpr(): pass def test_sympy__series__sequences__SeqPer(): from sympy.series.sequences import SeqPer assert _test_args(SeqPer((1, 2, 3), (0, 10))) def test_sympy__series__sequences__SeqFormula(): from sympy.series.sequences import SeqFormula assert _test_args(SeqFormula(x**2, (0, 10))) def test_sympy__series__sequences__RecursiveSeq(): from sympy.series.sequences import RecursiveSeq y = Function("y") n = symbols("n") assert _test_args(RecursiveSeq(y(n - 1) + y(n - 2), y(n), n, (0, 1))) assert _test_args(RecursiveSeq(y(n - 1) + y(n - 2), y(n), n)) def test_sympy__series__sequences__SeqExprOp(): from sympy.series.sequences import SeqExprOp, sequence s1 = sequence((1, 2, 3)) s2 = sequence(x**2) assert _test_args(SeqExprOp(s1, s2)) def test_sympy__series__sequences__SeqAdd(): from sympy.series.sequences import SeqAdd, sequence s1 = sequence((1, 2, 3)) s2 = sequence(x**2) assert _test_args(SeqAdd(s1, s2)) def test_sympy__series__sequences__SeqMul(): from sympy.series.sequences import SeqMul, sequence s1 = sequence((1, 2, 3)) s2 = sequence(x**2) assert _test_args(SeqMul(s1, s2)) @SKIP('Abstract Class') def test_sympy__series__series_class__SeriesBase(): pass def test_sympy__series__fourier__FourierSeries(): from sympy.series.fourier import fourier_series assert _test_args(fourier_series(x, (x, -pi, pi))) def test_sympy__series__fourier__FiniteFourierSeries(): from sympy.series.fourier import fourier_series assert _test_args(fourier_series(sin(pi*x), (x, -1, 1))) def test_sympy__series__formal__FormalPowerSeries(): from sympy.series.formal import fps assert _test_args(fps(log(1 + x), x)) def test_sympy__series__formal__Coeff(): from sympy.series.formal import fps assert _test_args(fps(x**2 + x + 1, x)) @SKIP('Abstract Class') def test_sympy__series__formal__FiniteFormalPowerSeries(): pass def test_sympy__series__formal__FormalPowerSeriesProduct(): from sympy.series.formal import fps f1, f2 = fps(sin(x)), fps(exp(x)) assert _test_args(f1.product(f2, x)) def test_sympy__series__formal__FormalPowerSeriesCompose(): from sympy.series.formal import fps f1, f2 = fps(exp(x)), fps(sin(x)) assert _test_args(f1.compose(f2, x)) def test_sympy__series__formal__FormalPowerSeriesInverse(): from sympy.series.formal import fps f1 = fps(exp(x)) assert _test_args(f1.inverse(x)) def test_sympy__simplify__hyperexpand__Hyper_Function(): from sympy.simplify.hyperexpand import Hyper_Function assert _test_args(Hyper_Function([2], [1])) def test_sympy__simplify__hyperexpand__G_Function(): from sympy.simplify.hyperexpand import G_Function assert _test_args(G_Function([2], [1], [], [])) @SKIP("abstract class") def test_sympy__tensor__array__ndim_array__ImmutableNDimArray(): pass def test_sympy__tensor__array__dense_ndim_array__ImmutableDenseNDimArray(): from sympy.tensor.array.dense_ndim_array import ImmutableDenseNDimArray densarr = ImmutableDenseNDimArray(range(10, 34), (2, 3, 4)) assert _test_args(densarr) def test_sympy__tensor__array__sparse_ndim_array__ImmutableSparseNDimArray(): from sympy.tensor.array.sparse_ndim_array import ImmutableSparseNDimArray sparr = ImmutableSparseNDimArray(range(10, 34), (2, 3, 4)) assert _test_args(sparr) def test_sympy__tensor__array__array_comprehension__ArrayComprehension(): from sympy.tensor.array.array_comprehension import ArrayComprehension arrcom = ArrayComprehension(x, (x, 1, 5)) assert _test_args(arrcom) def test_sympy__tensor__array__array_comprehension__ArrayComprehensionMap(): from sympy.tensor.array.array_comprehension import ArrayComprehensionMap arrcomma = ArrayComprehensionMap(lambda: 0, (x, 1, 5)) assert _test_args(arrcomma) def test_sympy__tensor__array__arrayop__Flatten(): from sympy.tensor.array.arrayop import Flatten from sympy.tensor.array.dense_ndim_array import ImmutableDenseNDimArray fla = Flatten(ImmutableDenseNDimArray(range(24)).reshape(2, 3, 4)) assert _test_args(fla) def test_sympy__tensor__array__array_derivatives__ArrayDerivative(): from sympy.tensor.array.array_derivatives import ArrayDerivative A = MatrixSymbol("A", 2, 2) arrder = ArrayDerivative(A, A, evaluate=False) assert _test_args(arrder) def test_sympy__tensor__array__expressions__array_expressions__ArraySymbol(): from sympy.tensor.array.expressions.array_expressions import ArraySymbol m, n, k = symbols("m n k") array = ArraySymbol("A", m, n, k, 2) assert _test_args(array) def test_sympy__tensor__array__expressions__array_expressions__ArrayElement(): from sympy.tensor.array.expressions.array_expressions import ArrayElement m, n, k = symbols("m n k") ae = ArrayElement("A", (m, n, k, 2)) assert _test_args(ae) def test_sympy__tensor__array__expressions__array_expressions__ZeroArray(): from sympy.tensor.array.expressions.array_expressions import ZeroArray m, n, k = symbols("m n k") za = ZeroArray(m, n, k, 2) assert _test_args(za) def test_sympy__tensor__array__expressions__array_expressions__OneArray(): from sympy.tensor.array.expressions.array_expressions import OneArray m, n, k = symbols("m n k") za = OneArray(m, n, k, 2) assert _test_args(za) def test_sympy__tensor__functions__TensorProduct(): from sympy.tensor.functions import TensorProduct A = MatrixSymbol('A', 3, 3) B = MatrixSymbol('B', 3, 3) tp = TensorProduct(A, B) assert _test_args(tp) def test_sympy__tensor__indexed__Idx(): from sympy.tensor.indexed import Idx assert _test_args(Idx('test')) assert _test_args(Idx(1, (0, 10))) def test_sympy__tensor__indexed__Indexed(): from sympy.tensor.indexed import Indexed, Idx assert _test_args(Indexed('A', Idx('i'), Idx('j'))) def test_sympy__tensor__indexed__IndexedBase(): from sympy.tensor.indexed import IndexedBase assert _test_args(IndexedBase('A', shape=(x, y))) assert _test_args(IndexedBase('A', 1)) assert _test_args(IndexedBase('A')[0, 1]) def test_sympy__tensor__tensor__TensorIndexType(): from sympy.tensor.tensor import TensorIndexType assert _test_args(TensorIndexType('Lorentz')) @SKIP("deprecated class") def test_sympy__tensor__tensor__TensorType(): pass def test_sympy__tensor__tensor__TensorSymmetry(): from sympy.tensor.tensor import TensorSymmetry, get_symmetric_group_sgs assert _test_args(TensorSymmetry(get_symmetric_group_sgs(2))) def test_sympy__tensor__tensor__TensorHead(): from sympy.tensor.tensor import TensorIndexType, TensorSymmetry, get_symmetric_group_sgs, TensorHead Lorentz = TensorIndexType('Lorentz', dummy_name='L') sym = TensorSymmetry(get_symmetric_group_sgs(1)) assert _test_args(TensorHead('p', [Lorentz], sym, 0)) def test_sympy__tensor__tensor__TensorIndex(): from sympy.tensor.tensor import TensorIndexType, TensorIndex Lorentz = TensorIndexType('Lorentz', dummy_name='L') assert _test_args(TensorIndex('i', Lorentz)) @SKIP("abstract class") def test_sympy__tensor__tensor__TensExpr(): pass def test_sympy__tensor__tensor__TensAdd(): from sympy.tensor.tensor import TensorIndexType, TensorSymmetry, get_symmetric_group_sgs, tensor_indices, TensAdd, tensor_heads Lorentz = TensorIndexType('Lorentz', dummy_name='L') a, b = tensor_indices('a,b', Lorentz) sym = TensorSymmetry(get_symmetric_group_sgs(1)) p, q = tensor_heads('p,q', [Lorentz], sym) t1 = p(a) t2 = q(a) assert _test_args(TensAdd(t1, t2)) def test_sympy__tensor__tensor__Tensor(): from sympy.tensor.tensor import TensorIndexType, TensorSymmetry, get_symmetric_group_sgs, tensor_indices, TensorHead Lorentz = TensorIndexType('Lorentz', dummy_name='L') a, b = tensor_indices('a,b', Lorentz) sym = TensorSymmetry(get_symmetric_group_sgs(1)) p = TensorHead('p', [Lorentz], sym) assert _test_args(p(a)) def test_sympy__tensor__tensor__TensMul(): from sympy.tensor.tensor import TensorIndexType, TensorSymmetry, get_symmetric_group_sgs, tensor_indices, tensor_heads Lorentz = TensorIndexType('Lorentz', dummy_name='L') a, b = tensor_indices('a,b', Lorentz) sym = TensorSymmetry(get_symmetric_group_sgs(1)) p, q = tensor_heads('p, q', [Lorentz], sym) assert _test_args(3*p(a)*q(b)) def test_sympy__tensor__tensor__TensorElement(): from sympy.tensor.tensor import TensorIndexType, TensorHead, TensorElement L = TensorIndexType("L") A = TensorHead("A", [L, L]) telem = TensorElement(A(x, y), {x: 1}) assert _test_args(telem) def test_sympy__tensor__toperators__PartialDerivative(): from sympy.tensor.tensor import TensorIndexType, tensor_indices, TensorHead from sympy.tensor.toperators import PartialDerivative Lorentz = TensorIndexType('Lorentz', dummy_name='L') a, b = tensor_indices('a,b', Lorentz) A = TensorHead("A", [Lorentz]) assert _test_args(PartialDerivative(A(a), A(b))) def test_as_coeff_add(): assert (7, (3*x, 4*x**2)) == (7 + 3*x + 4*x**2).as_coeff_add() def test_sympy__geometry__curve__Curve(): from sympy.geometry.curve import Curve assert _test_args(Curve((x, 1), (x, 0, 1))) def test_sympy__geometry__point__Point(): from sympy.geometry.point import Point assert _test_args(Point(0, 1)) def test_sympy__geometry__point__Point2D(): from sympy.geometry.point import Point2D assert _test_args(Point2D(0, 1)) def test_sympy__geometry__point__Point3D(): from sympy.geometry.point import Point3D assert _test_args(Point3D(0, 1, 2)) def test_sympy__geometry__ellipse__Ellipse(): from sympy.geometry.ellipse import Ellipse assert _test_args(Ellipse((0, 1), 2, 3)) def test_sympy__geometry__ellipse__Circle(): from sympy.geometry.ellipse import Circle assert _test_args(Circle((0, 1), 2)) def test_sympy__geometry__parabola__Parabola(): from sympy.geometry.parabola import Parabola from sympy.geometry.line import Line assert _test_args(Parabola((0, 0), Line((2, 3), (4, 3)))) @SKIP("abstract class") def test_sympy__geometry__line__LinearEntity(): pass def test_sympy__geometry__line__Line(): from sympy.geometry.line import Line assert _test_args(Line((0, 1), (2, 3))) def test_sympy__geometry__line__Ray(): from sympy.geometry.line import Ray assert _test_args(Ray((0, 1), (2, 3))) def test_sympy__geometry__line__Segment(): from sympy.geometry.line import Segment assert _test_args(Segment((0, 1), (2, 3))) @SKIP("abstract class") def test_sympy__geometry__line__LinearEntity2D(): pass def test_sympy__geometry__line__Line2D(): from sympy.geometry.line import Line2D assert _test_args(Line2D((0, 1), (2, 3))) def test_sympy__geometry__line__Ray2D(): from sympy.geometry.line import Ray2D assert _test_args(Ray2D((0, 1), (2, 3))) def test_sympy__geometry__line__Segment2D(): from sympy.geometry.line import Segment2D assert _test_args(Segment2D((0, 1), (2, 3))) @SKIP("abstract class") def test_sympy__geometry__line__LinearEntity3D(): pass def test_sympy__geometry__line__Line3D(): from sympy.geometry.line import Line3D assert _test_args(Line3D((0, 1, 1), (2, 3, 4))) def test_sympy__geometry__line__Segment3D(): from sympy.geometry.line import Segment3D assert _test_args(Segment3D((0, 1, 1), (2, 3, 4))) def test_sympy__geometry__line__Ray3D(): from sympy.geometry.line import Ray3D assert _test_args(Ray3D((0, 1, 1), (2, 3, 4))) def test_sympy__geometry__plane__Plane(): from sympy.geometry.plane import Plane assert _test_args(Plane((1, 1, 1), (-3, 4, -2), (1, 2, 3))) def test_sympy__geometry__polygon__Polygon(): from sympy.geometry.polygon import Polygon assert _test_args(Polygon((0, 1), (2, 3), (4, 5), (6, 7))) def test_sympy__geometry__polygon__RegularPolygon(): from sympy.geometry.polygon import RegularPolygon assert _test_args(RegularPolygon((0, 1), 2, 3, 4)) def test_sympy__geometry__polygon__Triangle(): from sympy.geometry.polygon import Triangle assert _test_args(Triangle((0, 1), (2, 3), (4, 5))) def test_sympy__geometry__entity__GeometryEntity(): from sympy.geometry.entity import GeometryEntity from sympy.geometry.point import Point assert _test_args(GeometryEntity(Point(1, 0), 1, [1, 2])) @SKIP("abstract class") def test_sympy__geometry__entity__GeometrySet(): pass def test_sympy__diffgeom__diffgeom__Manifold(): from sympy.diffgeom import Manifold assert _test_args(Manifold('name', 3)) def test_sympy__diffgeom__diffgeom__Patch(): from sympy.diffgeom import Manifold, Patch assert _test_args(Patch('name', Manifold('name', 3))) def test_sympy__diffgeom__diffgeom__CoordSystem(): from sympy.diffgeom import Manifold, Patch, CoordSystem assert _test_args(CoordSystem('name', Patch('name', Manifold('name', 3)))) assert _test_args(CoordSystem('name', Patch('name', Manifold('name', 3)), [a, b, c])) def test_sympy__diffgeom__diffgeom__CoordinateSymbol(): from sympy.diffgeom import Manifold, Patch, CoordSystem, CoordinateSymbol assert _test_args(CoordinateSymbol(CoordSystem('name', Patch('name', Manifold('name', 3)), [a, b, c]), 0)) def test_sympy__diffgeom__diffgeom__Point(): from sympy.diffgeom import Manifold, Patch, CoordSystem, Point assert _test_args(Point( CoordSystem('name', Patch('name', Manifold('name', 3)), [a, b, c]), [x, y])) def test_sympy__diffgeom__diffgeom__BaseScalarField(): from sympy.diffgeom import Manifold, Patch, CoordSystem, BaseScalarField cs = CoordSystem('name', Patch('name', Manifold('name', 3)), [a, b, c]) assert _test_args(BaseScalarField(cs, 0)) def test_sympy__diffgeom__diffgeom__BaseVectorField(): from sympy.diffgeom import Manifold, Patch, CoordSystem, BaseVectorField cs = CoordSystem('name', Patch('name', Manifold('name', 3)), [a, b, c]) assert _test_args(BaseVectorField(cs, 0)) def test_sympy__diffgeom__diffgeom__Differential(): from sympy.diffgeom import Manifold, Patch, CoordSystem, BaseScalarField, Differential cs = CoordSystem('name', Patch('name', Manifold('name', 3)), [a, b, c]) assert _test_args(Differential(BaseScalarField(cs, 0))) def test_sympy__diffgeom__diffgeom__Commutator(): from sympy.diffgeom import Manifold, Patch, CoordSystem, BaseVectorField, Commutator cs = CoordSystem('name', Patch('name', Manifold('name', 3)), [a, b, c]) cs1 = CoordSystem('name1', Patch('name', Manifold('name', 3)), [a, b, c]) v = BaseVectorField(cs, 0) v1 = BaseVectorField(cs1, 0) assert _test_args(Commutator(v, v1)) def test_sympy__diffgeom__diffgeom__TensorProduct(): from sympy.diffgeom import Manifold, Patch, CoordSystem, BaseScalarField, Differential, TensorProduct cs = CoordSystem('name', Patch('name', Manifold('name', 3)), [a, b, c]) d = Differential(BaseScalarField(cs, 0)) assert _test_args(TensorProduct(d, d)) def test_sympy__diffgeom__diffgeom__WedgeProduct(): from sympy.diffgeom import Manifold, Patch, CoordSystem, BaseScalarField, Differential, WedgeProduct cs = CoordSystem('name', Patch('name', Manifold('name', 3)), [a, b, c]) d = Differential(BaseScalarField(cs, 0)) d1 = Differential(BaseScalarField(cs, 1)) assert _test_args(WedgeProduct(d, d1)) def test_sympy__diffgeom__diffgeom__LieDerivative(): from sympy.diffgeom import Manifold, Patch, CoordSystem, BaseScalarField, Differential, BaseVectorField, LieDerivative cs = CoordSystem('name', Patch('name', Manifold('name', 3)), [a, b, c]) d = Differential(BaseScalarField(cs, 0)) v = BaseVectorField(cs, 0) assert _test_args(LieDerivative(v, d)) @XFAIL def test_sympy__diffgeom__diffgeom__BaseCovarDerivativeOp(): from sympy.diffgeom import Manifold, Patch, CoordSystem, BaseCovarDerivativeOp cs = CoordSystem('name', Patch('name', Manifold('name', 3)), [a, b, c]) assert _test_args(BaseCovarDerivativeOp(cs, 0, [[[0, ]*3, ]*3, ]*3)) def test_sympy__diffgeom__diffgeom__CovarDerivativeOp(): from sympy.diffgeom import Manifold, Patch, CoordSystem, BaseVectorField, CovarDerivativeOp cs = CoordSystem('name', Patch('name', Manifold('name', 3)), [a, b, c]) v = BaseVectorField(cs, 0) _test_args(CovarDerivativeOp(v, [[[0, ]*3, ]*3, ]*3)) def test_sympy__categories__baseclasses__Class(): from sympy.categories.baseclasses import Class assert _test_args(Class()) def test_sympy__categories__baseclasses__Object(): from sympy.categories import Object assert _test_args(Object("A")) @XFAIL def test_sympy__categories__baseclasses__Morphism(): from sympy.categories import Object, Morphism assert _test_args(Morphism(Object("A"), Object("B"))) def test_sympy__categories__baseclasses__IdentityMorphism(): from sympy.categories import Object, IdentityMorphism assert _test_args(IdentityMorphism(Object("A"))) def test_sympy__categories__baseclasses__NamedMorphism(): from sympy.categories import Object, NamedMorphism assert _test_args(NamedMorphism(Object("A"), Object("B"), "f")) def test_sympy__categories__baseclasses__CompositeMorphism(): from sympy.categories import Object, NamedMorphism, CompositeMorphism A = Object("A") B = Object("B") C = Object("C") f = NamedMorphism(A, B, "f") g = NamedMorphism(B, C, "g") assert _test_args(CompositeMorphism(f, g)) def test_sympy__categories__baseclasses__Diagram(): from sympy.categories import Object, NamedMorphism, Diagram A = Object("A") B = Object("B") f = NamedMorphism(A, B, "f") d = Diagram([f]) assert _test_args(d) def test_sympy__categories__baseclasses__Category(): from sympy.categories import Object, NamedMorphism, Diagram, Category A = Object("A") B = Object("B") C = Object("C") f = NamedMorphism(A, B, "f") g = NamedMorphism(B, C, "g") d1 = Diagram([f, g]) d2 = Diagram([f]) K = Category("K", commutative_diagrams=[d1, d2]) assert _test_args(K) def test_sympy__ntheory__factor___totient(): from sympy.ntheory.factor_ import totient k = symbols('k', integer=True) t = totient(k) assert _test_args(t) def test_sympy__ntheory__factor___reduced_totient(): from sympy.ntheory.factor_ import reduced_totient k = symbols('k', integer=True) t = reduced_totient(k) assert _test_args(t) def test_sympy__ntheory__factor___divisor_sigma(): from sympy.ntheory.factor_ import divisor_sigma k = symbols('k', integer=True) n = symbols('n', integer=True) t = divisor_sigma(n, k) assert _test_args(t) def test_sympy__ntheory__factor___udivisor_sigma(): from sympy.ntheory.factor_ import udivisor_sigma k = symbols('k', integer=True) n = symbols('n', integer=True) t = udivisor_sigma(n, k) assert _test_args(t) def test_sympy__ntheory__factor___primenu(): from sympy.ntheory.factor_ import primenu n = symbols('n', integer=True) t = primenu(n) assert _test_args(t) def test_sympy__ntheory__factor___primeomega(): from sympy.ntheory.factor_ import primeomega n = symbols('n', integer=True) t = primeomega(n) assert _test_args(t) def test_sympy__ntheory__residue_ntheory__mobius(): from sympy.ntheory import mobius assert _test_args(mobius(2)) def test_sympy__ntheory__generate__primepi(): from sympy.ntheory import primepi n = symbols('n') t = primepi(n) assert _test_args(t) def test_sympy__physics__optics__waves__TWave(): from sympy.physics.optics import TWave A, f, phi = symbols('A, f, phi') assert _test_args(TWave(A, f, phi)) def test_sympy__physics__optics__gaussopt__BeamParameter(): from sympy.physics.optics import BeamParameter assert _test_args(BeamParameter(530e-9, 1, w=1e-3)) def test_sympy__physics__optics__medium__Medium(): from sympy.physics.optics import Medium assert _test_args(Medium('m')) def test_sympy__tensor__array__expressions__array_expressions__ArrayContraction(): from sympy.tensor.array.expressions.array_expressions import ArrayContraction from sympy import IndexedBase A = symbols("A", cls=IndexedBase) assert _test_args(ArrayContraction(A, (0, 1))) def test_sympy__tensor__array__expressions__array_expressions__ArrayDiagonal(): from sympy.tensor.array.expressions.array_expressions import ArrayDiagonal from sympy import IndexedBase A = symbols("A", cls=IndexedBase) assert _test_args(ArrayDiagonal(A, (0, 1))) def test_sympy__tensor__array__expressions__array_expressions__ArrayTensorProduct(): from sympy.tensor.array.expressions.array_expressions import ArrayTensorProduct from sympy import IndexedBase A, B = symbols("A B", cls=IndexedBase) assert _test_args(ArrayTensorProduct(A, B)) def test_sympy__tensor__array__expressions__array_expressions__ArrayAdd(): from sympy.tensor.array.expressions.array_expressions import ArrayAdd from sympy import IndexedBase A, B = symbols("A B", cls=IndexedBase) assert _test_args(ArrayAdd(A, B)) def test_sympy__tensor__array__expressions__array_expressions__PermuteDims(): from sympy.tensor.array.expressions.array_expressions import PermuteDims A = MatrixSymbol("A", 4, 4) assert _test_args(PermuteDims(A, (1, 0))) def test_sympy__tensor__array__expressions__array_expressions__ArrayElementwiseApplyFunc(): from sympy.tensor.array.expressions.array_expressions import ArraySymbol, ArrayElementwiseApplyFunc A = ArraySymbol("A", 4) assert _test_args(ArrayElementwiseApplyFunc(exp, A)) def test_sympy__codegen__ast__Assignment(): from sympy.codegen.ast import Assignment assert _test_args(Assignment(x, y)) def test_sympy__codegen__cfunctions__expm1(): from sympy.codegen.cfunctions import expm1 assert _test_args(expm1(x)) def test_sympy__codegen__cfunctions__log1p(): from sympy.codegen.cfunctions import log1p assert _test_args(log1p(x)) def test_sympy__codegen__cfunctions__exp2(): from sympy.codegen.cfunctions import exp2 assert _test_args(exp2(x)) def test_sympy__codegen__cfunctions__log2(): from sympy.codegen.cfunctions import log2 assert _test_args(log2(x)) def test_sympy__codegen__cfunctions__fma(): from sympy.codegen.cfunctions import fma assert _test_args(fma(x, y, z)) def test_sympy__codegen__cfunctions__log10(): from sympy.codegen.cfunctions import log10 assert _test_args(log10(x)) def test_sympy__codegen__cfunctions__Sqrt(): from sympy.codegen.cfunctions import Sqrt assert _test_args(Sqrt(x)) def test_sympy__codegen__cfunctions__Cbrt(): from sympy.codegen.cfunctions import Cbrt assert _test_args(Cbrt(x)) def test_sympy__codegen__cfunctions__hypot(): from sympy.codegen.cfunctions import hypot assert _test_args(hypot(x, y)) def test_sympy__codegen__fnodes__FFunction(): from sympy.codegen.fnodes import FFunction assert _test_args(FFunction('f')) def test_sympy__codegen__fnodes__F95Function(): from sympy.codegen.fnodes import F95Function assert _test_args(F95Function('f')) def test_sympy__codegen__fnodes__isign(): from sympy.codegen.fnodes import isign assert _test_args(isign(1, x)) def test_sympy__codegen__fnodes__dsign(): from sympy.codegen.fnodes import dsign assert _test_args(dsign(1, x)) def test_sympy__codegen__fnodes__cmplx(): from sympy.codegen.fnodes import cmplx assert _test_args(cmplx(x, y)) def test_sympy__codegen__fnodes__kind(): from sympy.codegen.fnodes import kind assert _test_args(kind(x)) def test_sympy__codegen__fnodes__merge(): from sympy.codegen.fnodes import merge assert _test_args(merge(1, 2, Eq(x, 0))) def test_sympy__codegen__fnodes___literal(): from sympy.codegen.fnodes import _literal assert _test_args(_literal(1)) def test_sympy__codegen__fnodes__literal_sp(): from sympy.codegen.fnodes import literal_sp assert _test_args(literal_sp(1)) def test_sympy__codegen__fnodes__literal_dp(): from sympy.codegen.fnodes import literal_dp assert _test_args(literal_dp(1)) def test_sympy__codegen__matrix_nodes__MatrixSolve(): from sympy.matrices import MatrixSymbol from sympy.codegen.matrix_nodes import MatrixSolve A = MatrixSymbol('A', 3, 3) v = MatrixSymbol('x', 3, 1) assert _test_args(MatrixSolve(A, v)) def test_sympy__vector__coordsysrect__CoordSys3D(): from sympy.vector.coordsysrect import CoordSys3D assert _test_args(CoordSys3D('C')) def test_sympy__vector__point__Point(): from sympy.vector.point import Point assert _test_args(Point('P')) def test_sympy__vector__basisdependent__BasisDependent(): #from sympy.vector.basisdependent import BasisDependent #These classes have been created to maintain an OOP hierarchy #for Vectors and Dyadics. Are NOT meant to be initialized pass def test_sympy__vector__basisdependent__BasisDependentMul(): #from sympy.vector.basisdependent import BasisDependentMul #These classes have been created to maintain an OOP hierarchy #for Vectors and Dyadics. Are NOT meant to be initialized pass def test_sympy__vector__basisdependent__BasisDependentAdd(): #from sympy.vector.basisdependent import BasisDependentAdd #These classes have been created to maintain an OOP hierarchy #for Vectors and Dyadics. Are NOT meant to be initialized pass def test_sympy__vector__basisdependent__BasisDependentZero(): #from sympy.vector.basisdependent import BasisDependentZero #These classes have been created to maintain an OOP hierarchy #for Vectors and Dyadics. Are NOT meant to be initialized pass def test_sympy__vector__vector__BaseVector(): from sympy.vector.vector import BaseVector from sympy.vector.coordsysrect import CoordSys3D C = CoordSys3D('C') assert _test_args(BaseVector(0, C, ' ', ' ')) def test_sympy__vector__vector__VectorAdd(): from sympy.vector.vector import VectorAdd, VectorMul from sympy.vector.coordsysrect import CoordSys3D C = CoordSys3D('C') from sympy.abc import a, b, c, x, y, z v1 = a*C.i + b*C.j + c*C.k v2 = x*C.i + y*C.j + z*C.k assert _test_args(VectorAdd(v1, v2)) assert _test_args(VectorMul(x, v1)) def test_sympy__vector__vector__VectorMul(): from sympy.vector.vector import VectorMul from sympy.vector.coordsysrect import CoordSys3D C = CoordSys3D('C') from sympy.abc import a assert _test_args(VectorMul(a, C.i)) def test_sympy__vector__vector__VectorZero(): from sympy.vector.vector import VectorZero assert _test_args(VectorZero()) def test_sympy__vector__vector__Vector(): #from sympy.vector.vector import Vector #Vector is never to be initialized using args pass def test_sympy__vector__vector__Cross(): from sympy.vector.vector import Cross from sympy.vector.coordsysrect import CoordSys3D C = CoordSys3D('C') _test_args(Cross(C.i, C.j)) def test_sympy__vector__vector__Dot(): from sympy.vector.vector import Dot from sympy.vector.coordsysrect import CoordSys3D C = CoordSys3D('C') _test_args(Dot(C.i, C.j)) def test_sympy__vector__dyadic__Dyadic(): #from sympy.vector.dyadic import Dyadic #Dyadic is never to be initialized using args pass def test_sympy__vector__dyadic__BaseDyadic(): from sympy.vector.dyadic import BaseDyadic from sympy.vector.coordsysrect import CoordSys3D C = CoordSys3D('C') assert _test_args(BaseDyadic(C.i, C.j)) def test_sympy__vector__dyadic__DyadicMul(): from sympy.vector.dyadic import BaseDyadic, DyadicMul from sympy.vector.coordsysrect import CoordSys3D C = CoordSys3D('C') assert _test_args(DyadicMul(3, BaseDyadic(C.i, C.j))) def test_sympy__vector__dyadic__DyadicAdd(): from sympy.vector.dyadic import BaseDyadic, DyadicAdd from sympy.vector.coordsysrect import CoordSys3D C = CoordSys3D('C') assert _test_args(2 * DyadicAdd(BaseDyadic(C.i, C.i), BaseDyadic(C.i, C.j))) def test_sympy__vector__dyadic__DyadicZero(): from sympy.vector.dyadic import DyadicZero assert _test_args(DyadicZero()) def test_sympy__vector__deloperator__Del(): from sympy.vector.deloperator import Del assert _test_args(Del()) def test_sympy__vector__implicitregion__ImplicitRegion(): from sympy.vector.implicitregion import ImplicitRegion from sympy.abc import x, y assert _test_args(ImplicitRegion((x, y), y**3 - 4*x)) def test_sympy__vector__integrals__ParametricIntegral(): from sympy.vector.integrals import ParametricIntegral from sympy.vector.parametricregion import ParametricRegion from sympy.vector.coordsysrect import CoordSys3D C = CoordSys3D('C') assert _test_args(ParametricIntegral(C.y*C.i - 10*C.j,\ ParametricRegion((x, y), (x, 1, 3), (y, -2, 2)))) def test_sympy__vector__operators__Curl(): from sympy.vector.operators import Curl from sympy.vector.coordsysrect import CoordSys3D C = CoordSys3D('C') assert _test_args(Curl(C.i)) def test_sympy__vector__operators__Laplacian(): from sympy.vector.operators import Laplacian from sympy.vector.coordsysrect import CoordSys3D C = CoordSys3D('C') assert _test_args(Laplacian(C.i)) def test_sympy__vector__operators__Divergence(): from sympy.vector.operators import Divergence from sympy.vector.coordsysrect import CoordSys3D C = CoordSys3D('C') assert _test_args(Divergence(C.i)) def test_sympy__vector__operators__Gradient(): from sympy.vector.operators import Gradient from sympy.vector.coordsysrect import CoordSys3D C = CoordSys3D('C') assert _test_args(Gradient(C.x)) def test_sympy__vector__orienters__Orienter(): #from sympy.vector.orienters import Orienter #Not to be initialized pass def test_sympy__vector__orienters__ThreeAngleOrienter(): #from sympy.vector.orienters import ThreeAngleOrienter #Not to be initialized pass def test_sympy__vector__orienters__AxisOrienter(): from sympy.vector.orienters import AxisOrienter from sympy.vector.coordsysrect import CoordSys3D C = CoordSys3D('C') assert _test_args(AxisOrienter(x, C.i)) def test_sympy__vector__orienters__BodyOrienter(): from sympy.vector.orienters import BodyOrienter assert _test_args(BodyOrienter(x, y, z, '123')) def test_sympy__vector__orienters__SpaceOrienter(): from sympy.vector.orienters import SpaceOrienter assert _test_args(SpaceOrienter(x, y, z, '123')) def test_sympy__vector__orienters__QuaternionOrienter(): from sympy.vector.orienters import QuaternionOrienter a, b, c, d = symbols('a b c d') assert _test_args(QuaternionOrienter(a, b, c, d)) def test_sympy__vector__parametricregion__ParametricRegion(): from sympy.abc import t from sympy.vector.parametricregion import ParametricRegion assert _test_args(ParametricRegion((t, t**3), (t, 0, 2))) def test_sympy__vector__scalar__BaseScalar(): from sympy.vector.scalar import BaseScalar from sympy.vector.coordsysrect import CoordSys3D C = CoordSys3D('C') assert _test_args(BaseScalar(0, C, ' ', ' ')) def test_sympy__physics__wigner__Wigner3j(): from sympy.physics.wigner import Wigner3j assert _test_args(Wigner3j(0, 0, 0, 0, 0, 0)) def test_sympy__integrals__rubi__symbol__matchpyWC(): from sympy.integrals.rubi.symbol import matchpyWC assert _test_args(matchpyWC(1, True, 'a')) def test_sympy__integrals__rubi__utility_function__rubi_unevaluated_expr(): from sympy.integrals.rubi.utility_function import rubi_unevaluated_expr a = symbols('a') assert _test_args(rubi_unevaluated_expr(a)) def test_sympy__integrals__rubi__utility_function__rubi_exp(): from sympy.integrals.rubi.utility_function import rubi_exp assert _test_args(rubi_exp(5)) def test_sympy__integrals__rubi__utility_function__rubi_log(): from sympy.integrals.rubi.utility_function import rubi_log assert _test_args(rubi_log(5)) def test_sympy__integrals__rubi__utility_function__Int(): from sympy.integrals.rubi.utility_function import Int assert _test_args(Int(5, x)) def test_sympy__integrals__rubi__utility_function__Util_Coefficient(): from sympy.integrals.rubi.utility_function import Util_Coefficient a, x = symbols('a x') assert _test_args(Util_Coefficient(a, x)) def test_sympy__integrals__rubi__utility_function__Gamma(): from sympy.integrals.rubi.utility_function import Gamma assert _test_args(Gamma(5)) def test_sympy__integrals__rubi__utility_function__Util_Part(): from sympy.integrals.rubi.utility_function import Util_Part a, b = symbols('a b') assert _test_args(Util_Part(a + b, 0)) def test_sympy__integrals__rubi__utility_function__PolyGamma(): from sympy.integrals.rubi.utility_function import PolyGamma assert _test_args(PolyGamma(1, 1)) def test_sympy__integrals__rubi__utility_function__ProductLog(): from sympy.integrals.rubi.utility_function import ProductLog assert _test_args(ProductLog(1)) def test_sympy__combinatorics__schur_number__SchurNumber(): from sympy.combinatorics.schur_number import SchurNumber assert _test_args(SchurNumber(1)) def test_sympy__combinatorics__perm_groups__SymmetricPermutationGroup(): from sympy.combinatorics.perm_groups import SymmetricPermutationGroup assert _test_args(SymmetricPermutationGroup(5)) def test_sympy__combinatorics__perm_groups__Coset(): from sympy.combinatorics.permutations import Permutation from sympy.combinatorics.perm_groups import PermutationGroup, Coset a = Permutation(1, 2) b = Permutation(0, 1) G = PermutationGroup([a, b]) assert _test_args(Coset(a, G))
2866e9f751222cf966f9d8f9eb2232323788022a70673e54d138fd19a0a8e762
"""Tests for tools for manipulating of large commutative expressions. """ from sympy import (S, Add, sin, Mul, Symbol, oo, Integral, sqrt, Tuple, I, Function, Interval, O, symbols, simplify, collect, Sum, Basic, Dict, root, exp, cos, Dummy, log, Rational) from sympy.core.exprtools import (decompose_power, Factors, Term, _gcd_terms, gcd_terms, factor_terms, factor_nc, _mask_nc, _monotonic_sign) from sympy.core.mul import _keep_coeff as _keep_coeff from sympy.simplify.cse_opts import sub_pre from sympy.testing.pytest import raises from sympy.abc import a, b, t, x, y, z def test_decompose_power(): assert decompose_power(x) == (x, 1) assert decompose_power(x**2) == (x, 2) assert decompose_power(x**(2*y)) == (x**y, 2) assert decompose_power(x**(2*y/3)) == (x**(y/3), 2) assert decompose_power(x**(y*Rational(2, 3))) == (x**(y/3), 2) def test_Factors(): assert Factors() == Factors({}) == Factors(S.One) assert Factors().as_expr() is S.One assert Factors({x: 2, y: 3, sin(x): 4}).as_expr() == x**2*y**3*sin(x)**4 assert Factors(S.Infinity) == Factors({oo: 1}) assert Factors(S.NegativeInfinity) == Factors({oo: 1, -1: 1}) # issue #18059: assert Factors((x**2)**S.Half).as_expr() == (x**2)**S.Half a = Factors({x: 5, y: 3, z: 7}) b = Factors({ y: 4, z: 3, t: 10}) assert a.mul(b) == a*b == Factors({x: 5, y: 7, z: 10, t: 10}) assert a.div(b) == divmod(a, b) == \ (Factors({x: 5, z: 4}), Factors({y: 1, t: 10})) assert a.quo(b) == a/b == Factors({x: 5, z: 4}) assert a.rem(b) == a % b == Factors({y: 1, t: 10}) assert a.pow(3) == a**3 == Factors({x: 15, y: 9, z: 21}) assert b.pow(3) == b**3 == Factors({y: 12, z: 9, t: 30}) assert a.gcd(b) == Factors({y: 3, z: 3}) assert a.lcm(b) == Factors({x: 5, y: 4, z: 7, t: 10}) a = Factors({x: 4, y: 7, t: 7}) b = Factors({z: 1, t: 3}) assert a.normal(b) == (Factors({x: 4, y: 7, t: 4}), Factors({z: 1})) assert Factors(sqrt(2)*x).as_expr() == sqrt(2)*x assert Factors(-I)*I == Factors() assert Factors({S.NegativeOne: S(3)})*Factors({S.NegativeOne: S.One, I: S(5)}) == \ Factors(I) assert Factors(sqrt(I)*I) == Factors(I**(S(3)/2)) == Factors({I: S(3)/2}) assert Factors({I: S(3)/2}).as_expr() == I**(S(3)/2) assert Factors(S(2)**x).div(S(3)**x) == \ (Factors({S(2): x}), Factors({S(3): x})) assert Factors(2**(2*x + 2)).div(S(8)) == \ (Factors({S(2): 2*x + 2}), Factors({S(8): S.One})) # coverage # /!\ things break if this is not True assert Factors({S.NegativeOne: Rational(3, 2)}) == Factors({I: S.One, S.NegativeOne: S.One}) assert Factors({I: S.One, S.NegativeOne: Rational(1, 3)}).as_expr() == I*(-1)**Rational(1, 3) assert Factors(-1.) == Factors({S.NegativeOne: S.One, S(1.): 1}) assert Factors(-2.) == Factors({S.NegativeOne: S.One, S(2.): 1}) assert Factors((-2.)**x) == Factors({S(-2.): x}) assert Factors(S(-2)) == Factors({S.NegativeOne: S.One, S(2): 1}) assert Factors(S.Half) == Factors({S(2): -S.One}) assert Factors(Rational(3, 2)) == Factors({S(3): S.One, S(2): S.NegativeOne}) assert Factors({I: S.One}) == Factors(I) assert Factors({-1.0: 2, I: 1}) == Factors({S(1.0): 1, I: 1}) assert Factors({S.NegativeOne: Rational(-3, 2)}).as_expr() == I A = symbols('A', commutative=False) assert Factors(2*A**2) == Factors({S(2): 1, A**2: 1}) assert Factors(I) == Factors({I: S.One}) assert Factors(x).normal(S(2)) == (Factors(x), Factors(S(2))) assert Factors(x).normal(S.Zero) == (Factors(), Factors(S.Zero)) raises(ZeroDivisionError, lambda: Factors(x).div(S.Zero)) assert Factors(x).mul(S(2)) == Factors(2*x) assert Factors(x).mul(S.Zero).is_zero assert Factors(x).mul(1/x).is_one assert Factors(x**sqrt(2)**3).as_expr() == x**(2*sqrt(2)) assert Factors(x)**Factors(S(2)) == Factors(x**2) assert Factors(x).gcd(S.Zero) == Factors(x) assert Factors(x).lcm(S.Zero).is_zero assert Factors(S.Zero).div(x) == (Factors(S.Zero), Factors()) assert Factors(x).div(x) == (Factors(), Factors()) assert Factors({x: .2})/Factors({x: .2}) == Factors() assert Factors(x) != Factors() assert Factors(S.Zero).normal(x) == (Factors(S.Zero), Factors()) n, d = x**(2 + y), x**2 f = Factors(n) assert f.div(d) == f.normal(d) == (Factors(x**y), Factors()) assert f.gcd(d) == Factors() d = x**y assert f.div(d) == f.normal(d) == (Factors(x**2), Factors()) assert f.gcd(d) == Factors(d) n = d = 2**x f = Factors(n) assert f.div(d) == f.normal(d) == (Factors(), Factors()) assert f.gcd(d) == Factors(d) n, d = 2**x, 2**y f = Factors(n) assert f.div(d) == f.normal(d) == (Factors({S(2): x}), Factors({S(2): y})) assert f.gcd(d) == Factors() # extraction of constant only n = x**(x + 3) assert Factors(n).normal(x**-3) == (Factors({x: x + 6}), Factors({})) assert Factors(n).normal(x**3) == (Factors({x: x}), Factors({})) assert Factors(n).normal(x**4) == (Factors({x: x}), Factors({x: 1})) assert Factors(n).normal(x**(y - 3)) == \ (Factors({x: x + 6}), Factors({x: y})) assert Factors(n).normal(x**(y + 3)) == (Factors({x: x}), Factors({x: y})) assert Factors(n).normal(x**(y + 4)) == \ (Factors({x: x}), Factors({x: y + 1})) assert Factors(n).div(x**-3) == (Factors({x: x + 6}), Factors({})) assert Factors(n).div(x**3) == (Factors({x: x}), Factors({})) assert Factors(n).div(x**4) == (Factors({x: x}), Factors({x: 1})) assert Factors(n).div(x**(y - 3)) == \ (Factors({x: x + 6}), Factors({x: y})) assert Factors(n).div(x**(y + 3)) == (Factors({x: x}), Factors({x: y})) assert Factors(n).div(x**(y + 4)) == \ (Factors({x: x}), Factors({x: y + 1})) assert Factors(3 * x / 2) == Factors({3: 1, 2: -1, x: 1}) assert Factors(x * x / y) == Factors({x: 2, y: -1}) assert Factors(27 * x / y**9) == Factors({27: 1, x: 1, y: -9}) def test_Term(): a = Term(4*x*y**2/z/t**3) b = Term(2*x**3*y**5/t**3) assert a == Term(4, Factors({x: 1, y: 2}), Factors({z: 1, t: 3})) assert b == Term(2, Factors({x: 3, y: 5}), Factors({t: 3})) assert a.as_expr() == 4*x*y**2/z/t**3 assert b.as_expr() == 2*x**3*y**5/t**3 assert a.inv() == \ Term(S.One/4, Factors({z: 1, t: 3}), Factors({x: 1, y: 2})) assert b.inv() == Term(S.Half, Factors({t: 3}), Factors({x: 3, y: 5})) assert a.mul(b) == a*b == \ Term(8, Factors({x: 4, y: 7}), Factors({z: 1, t: 6})) assert a.quo(b) == a/b == Term(2, Factors({}), Factors({x: 2, y: 3, z: 1})) assert a.pow(3) == a**3 == \ Term(64, Factors({x: 3, y: 6}), Factors({z: 3, t: 9})) assert b.pow(3) == b**3 == Term(8, Factors({x: 9, y: 15}), Factors({t: 9})) assert a.pow(-3) == a**(-3) == \ Term(S.One/64, Factors({z: 3, t: 9}), Factors({x: 3, y: 6})) assert b.pow(-3) == b**(-3) == \ Term(S.One/8, Factors({t: 9}), Factors({x: 9, y: 15})) assert a.gcd(b) == Term(2, Factors({x: 1, y: 2}), Factors({t: 3})) assert a.lcm(b) == Term(4, Factors({x: 3, y: 5}), Factors({z: 1, t: 3})) a = Term(4*x*y**2/z/t**3) b = Term(2*x**3*y**5*t**7) assert a.mul(b) == Term(8, Factors({x: 4, y: 7, t: 4}), Factors({z: 1})) assert Term((2*x + 2)**3) == Term(8, Factors({x + 1: 3}), Factors({})) assert Term((2*x + 2)*(3*x + 6)**2) == \ Term(18, Factors({x + 1: 1, x + 2: 2}), Factors({})) def test_gcd_terms(): f = 2*(x + 1)*(x + 4)/(5*x**2 + 5) + (2*x + 2)*(x + 5)/(x**2 + 1)/5 + \ (2*x + 2)*(x + 6)/(5*x**2 + 5) assert _gcd_terms(f) == ((Rational(6, 5))*((1 + x)/(1 + x**2)), 5 + x, 1) assert _gcd_terms(Add.make_args(f)) == \ ((Rational(6, 5))*((1 + x)/(1 + x**2)), 5 + x, 1) newf = (Rational(6, 5))*((1 + x)*(5 + x)/(1 + x**2)) assert gcd_terms(f) == newf args = Add.make_args(f) # non-Basic sequences of terms treated as terms of Add assert gcd_terms(list(args)) == newf assert gcd_terms(tuple(args)) == newf assert gcd_terms(set(args)) == newf # but a Basic sequence is treated as a container assert gcd_terms(Tuple(*args)) != newf assert gcd_terms(Basic(Tuple(1, 3*y + 3*x*y), Tuple(1, 3))) == \ Basic((1, 3*y*(x + 1)), (1, 3)) # but we shouldn't change keys of a dictionary or some may be lost assert gcd_terms(Dict((x*(1 + y), 2), (x + x*y, y + x*y))) == \ Dict({x*(y + 1): 2, x + x*y: y*(1 + x)}) assert gcd_terms((2*x + 2)**3 + (2*x + 2)**2) == 4*(x + 1)**2*(2*x + 3) assert gcd_terms(0) == 0 assert gcd_terms(1) == 1 assert gcd_terms(x) == x assert gcd_terms(2 + 2*x) == Mul(2, 1 + x, evaluate=False) arg = x*(2*x + 4*y) garg = 2*x*(x + 2*y) assert gcd_terms(arg) == garg assert gcd_terms(sin(arg)) == sin(garg) # issue 6139-like alpha, alpha1, alpha2, alpha3 = symbols('alpha:4') a = alpha**2 - alpha*x**2 + alpha + x**3 - x*(alpha + 1) rep = (alpha, (1 + sqrt(5))/2 + alpha1*x + alpha2*x**2 + alpha3*x**3) s = (a/(x - alpha)).subs(*rep).series(x, 0, 1) assert simplify(collect(s, x)) == -sqrt(5)/2 - Rational(3, 2) + O(x) # issue 5917 assert _gcd_terms([S.Zero, S.Zero]) == (0, 0, 1) assert _gcd_terms([2*x + 4]) == (2, x + 2, 1) eq = x/(x + 1/x) assert gcd_terms(eq, fraction=False) == eq eq = x/2/y + 1/x/y assert gcd_terms(eq, fraction=True, clear=True) == \ (x**2 + 2)/(2*x*y) assert gcd_terms(eq, fraction=True, clear=False) == \ (x**2/2 + 1)/(x*y) assert gcd_terms(eq, fraction=False, clear=True) == \ (x + 2/x)/(2*y) assert gcd_terms(eq, fraction=False, clear=False) == \ (x/2 + 1/x)/y def test_factor_terms(): A = Symbol('A', commutative=False) assert factor_terms(9*(x + x*y + 1) + (3*x + 3)**(2 + 2*x)) == \ 9*x*y + 9*x + _keep_coeff(S(3), x + 1)**_keep_coeff(S(2), x + 1) + 9 assert factor_terms(9*(x + x*y + 1) + (3)**(2 + 2*x)) == \ _keep_coeff(S(9), 3**(2*x) + x*y + x + 1) assert factor_terms(3**(2 + 2*x) + a*3**(2 + 2*x)) == \ 9*3**(2*x)*(a + 1) assert factor_terms(x + x*A) == \ x*(1 + A) assert factor_terms(sin(x + x*A)) == \ sin(x*(1 + A)) assert factor_terms((3*x + 3)**((2 + 2*x)/3)) == \ _keep_coeff(S(3), x + 1)**_keep_coeff(Rational(2, 3), x + 1) assert factor_terms(x + (x*y + x)**(3*x + 3)) == \ x + (x*(y + 1))**_keep_coeff(S(3), x + 1) assert factor_terms(a*(x + x*y) + b*(x*2 + y*x*2)) == \ x*(a + 2*b)*(y + 1) i = Integral(x, (x, 0, oo)) assert factor_terms(i) == i assert factor_terms(x/2 + y) == x/2 + y # fraction doesn't apply to integer denominators assert factor_terms(x/2 + y, fraction=True) == x/2 + y # clear *does* apply to the integer denominators assert factor_terms(x/2 + y, clear=True) == Mul(S.Half, x + 2*y, evaluate=False) # check radical extraction eq = sqrt(2) + sqrt(10) assert factor_terms(eq) == eq assert factor_terms(eq, radical=True) == sqrt(2)*(1 + sqrt(5)) eq = root(-6, 3) + root(6, 3) assert factor_terms(eq, radical=True) == 6**(S.One/3)*(1 + (-1)**(S.One/3)) eq = [x + x*y] ans = [x*(y + 1)] for c in [list, tuple, set]: assert factor_terms(c(eq)) == c(ans) assert factor_terms(Tuple(x + x*y)) == Tuple(x*(y + 1)) assert factor_terms(Interval(0, 1)) == Interval(0, 1) e = 1/sqrt(a/2 + 1) assert factor_terms(e, clear=False) == 1/sqrt(a/2 + 1) assert factor_terms(e, clear=True) == sqrt(2)/sqrt(a + 2) eq = x/(x + 1/x) + 1/(x**2 + 1) assert factor_terms(eq, fraction=False) == eq assert factor_terms(eq, fraction=True) == 1 assert factor_terms((1/(x**3 + x**2) + 2/x**2)*y) == \ y*(2 + 1/(x + 1))/x**2 # if not True, then processesing for this in factor_terms is not necessary assert gcd_terms(-x - y) == -x - y assert factor_terms(-x - y) == Mul(-1, x + y, evaluate=False) # if not True, then "special" processesing in factor_terms is not necessary assert gcd_terms(exp(Mul(-1, x + 1))) == exp(-x - 1) e = exp(-x - 2) + x assert factor_terms(e) == exp(Mul(-1, x + 2, evaluate=False)) + x assert factor_terms(e, sign=False) == e assert factor_terms(exp(-4*x - 2) - x) == -x + exp(Mul(-2, 2*x + 1, evaluate=False)) # sum/integral tests for F in (Sum, Integral): assert factor_terms(F(x, (y, 1, 10))) == x * F(1, (y, 1, 10)) assert factor_terms(F(x, (y, 1, 10)) + x) == x * (1 + F(1, (y, 1, 10))) assert factor_terms(F(x*y + x*y**2, (y, 1, 10))) == x*F(y*(y + 1), (y, 1, 10)) def test_xreplace(): e = Mul(2, 1 + x, evaluate=False) assert e.xreplace({}) == e assert e.xreplace({y: x}) == e def test_factor_nc(): x, y = symbols('x,y') k = symbols('k', integer=True) n, m, o = symbols('n,m,o', commutative=False) # mul and multinomial expansion is needed from sympy.core.function import _mexpand e = x*(1 + y)**2 assert _mexpand(e) == x + x*2*y + x*y**2 def factor_nc_test(e): ex = _mexpand(e) assert ex.is_Add f = factor_nc(ex) assert not f.is_Add and _mexpand(f) == ex factor_nc_test(x*(1 + y)) factor_nc_test(n*(x + 1)) factor_nc_test(n*(x + m)) factor_nc_test((x + m)*n) factor_nc_test(n*m*(x*o + n*o*m)*n) s = Sum(x, (x, 1, 2)) factor_nc_test(x*(1 + s)) factor_nc_test(x*(1 + s)*s) factor_nc_test(x*(1 + sin(s))) factor_nc_test((1 + n)**2) factor_nc_test((x + n)*(x + m)*(x + y)) factor_nc_test(x*(n*m + 1)) factor_nc_test(x*(n*m + x)) factor_nc_test(x*(x*n*m + 1)) factor_nc_test(x*n*(x*m + 1)) factor_nc_test(x*(m*n + x*n*m)) factor_nc_test(n*(1 - m)*n**2) factor_nc_test((n + m)**2) factor_nc_test((n - m)*(n + m)**2) factor_nc_test((n + m)**2*(n - m)) factor_nc_test((m - n)*(n + m)**2*(n - m)) assert factor_nc(n*(n + n*m)) == n**2*(1 + m) assert factor_nc(m*(m*n + n*m*n**2)) == m*(m + n*m*n)*n eq = m*sin(n) - sin(n)*m assert factor_nc(eq) == eq # for coverage: from sympy.physics.secondquant import Commutator from sympy import factor eq = 1 + x*Commutator(m, n) assert factor_nc(eq) == eq eq = x*Commutator(m, n) + x*Commutator(m, o)*Commutator(m, n) assert factor(eq) == x*(1 + Commutator(m, o))*Commutator(m, n) # issue 6534 assert (2*n + 2*m).factor() == 2*(n + m) # issue 6701 assert factor_nc(n**k + n**(k + 1)) == n**k*(1 + n) assert factor_nc((m*n)**k + (m*n)**(k + 1)) == (1 + m*n)*(m*n)**k # issue 6918 assert factor_nc(-n*(2*x**2 + 2*x)) == -2*n*x*(x + 1) def test_issue_6360(): a, b = symbols("a b") apb = a + b eq = apb + apb**2*(-2*a - 2*b) assert factor_terms(sub_pre(eq)) == a + b - 2*(a + b)**3 def test_issue_7903(): a = symbols(r'a', real=True) t = exp(I*cos(a)) + exp(-I*sin(a)) assert t.simplify() def test_issue_8263(): F, G = symbols('F, G', commutative=False, cls=Function) x, y = symbols('x, y') expr, dummies, _ = _mask_nc(F(x)*G(y) - G(y)*F(x)) for v in dummies.values(): assert not v.is_commutative assert not expr.is_zero def test_monotonic_sign(): F = _monotonic_sign x = symbols('x') assert F(x) is None assert F(-x) is None assert F(Dummy(prime=True)) == 2 assert F(Dummy(prime=True, odd=True)) == 3 assert F(Dummy(composite=True)) == 4 assert F(Dummy(composite=True, odd=True)) == 9 assert F(Dummy(positive=True, integer=True)) == 1 assert F(Dummy(positive=True, even=True)) == 2 assert F(Dummy(positive=True, even=True, prime=False)) == 4 assert F(Dummy(negative=True, integer=True)) == -1 assert F(Dummy(negative=True, even=True)) == -2 assert F(Dummy(zero=True)) == 0 assert F(Dummy(nonnegative=True)) == 0 assert F(Dummy(nonpositive=True)) == 0 assert F(Dummy(positive=True) + 1).is_positive assert F(Dummy(positive=True, integer=True) - 1).is_nonnegative assert F(Dummy(positive=True) - 1) is None assert F(Dummy(negative=True) + 1) is None assert F(Dummy(negative=True, integer=True) - 1).is_nonpositive assert F(Dummy(negative=True) - 1).is_negative assert F(-Dummy(positive=True) + 1) is None assert F(-Dummy(positive=True, integer=True) - 1).is_negative assert F(-Dummy(positive=True) - 1).is_negative assert F(-Dummy(negative=True) + 1).is_positive assert F(-Dummy(negative=True, integer=True) - 1).is_nonnegative assert F(-Dummy(negative=True) - 1) is None x = Dummy(negative=True) assert F(x**3).is_nonpositive assert F(x**3 + log(2)*x - 1).is_negative x = Dummy(positive=True) assert F(-x**3).is_nonpositive p = Dummy(positive=True) assert F(1/p).is_positive assert F(p/(p + 1)).is_positive p = Dummy(nonnegative=True) assert F(p/(p + 1)).is_nonnegative p = Dummy(positive=True) assert F(-1/p).is_negative p = Dummy(nonpositive=True) assert F(p/(-p + 1)).is_nonpositive p = Dummy(positive=True, integer=True) q = Dummy(positive=True, integer=True) assert F(-2/p/q).is_negative assert F(-2/(p - 1)/q) is None assert F((p - 1)*q + 1).is_positive assert F(-(p - 1)*q - 1).is_negative def test_issue_17256(): from sympy import Symbol, Range, Sum x = Symbol('x') s1 = Sum(x + 1, (x, 1, 9)) s2 = Sum(x + 1, (x, Range(1, 10))) a = Symbol('a') r1 = s1.xreplace({x:a}) r2 = s2.xreplace({x:a}) r1.doit() == r2.doit() s1 = Sum(x + 1, (x, 0, 9)) s2 = Sum(x + 1, (x, Range(10))) a = Symbol('a') r1 = s1.xreplace({x:a}) r2 = s2.xreplace({x:a}) assert r1 == r2
7828598c4db9c9be8ca0552083c2a5192bf4dba3536c57ad506a802d9f99ee08
from sympy.core import ( Basic, Rational, Symbol, S, Float, Integer, Mul, Number, Pow, Expr, I, nan, pi, symbols, oo, zoo, N) from sympy.core.parameters import global_parameters from sympy.core.tests.test_evalf import NS from sympy.core.function import expand_multinomial from sympy.functions.elementary.miscellaneous import sqrt, cbrt from sympy.functions.elementary.exponential import exp, log from sympy.functions.special.error_functions import erf from sympy.functions.elementary.trigonometric import ( sin, cos, tan, sec, csc, sinh, cosh, tanh, atan) from sympy.polys import Poly from sympy.series.order import O from sympy.sets import FiniteSet from sympy.core.expr import unchanged from sympy.core.power import power from sympy.testing.pytest import warns_deprecated_sympy, _both_exp_pow def test_rational(): a = Rational(1, 5) r = sqrt(5)/5 assert sqrt(a) == r assert 2*sqrt(a) == 2*r r = a*a**S.Half assert a**Rational(3, 2) == r assert 2*a**Rational(3, 2) == 2*r r = a**5*a**Rational(2, 3) assert a**Rational(17, 3) == r assert 2 * a**Rational(17, 3) == 2*r def test_large_rational(): e = (Rational(123712**12 - 1, 7) + Rational(1, 7))**Rational(1, 3) assert e == 234232585392159195136 * (Rational(1, 7)**Rational(1, 3)) def test_negative_real(): def feq(a, b): return abs(a - b) < 1E-10 assert feq(S.One / Float(-0.5), -Integer(2)) def test_expand(): x = Symbol('x') assert (2**(-1 - x)).expand() == S.Half*2**(-x) def test_issue_3449(): #test if powers are simplified correctly #see also issue 3995 x = Symbol('x') assert ((x**Rational(1, 3))**Rational(2)) == x**Rational(2, 3) assert ( (x**Rational(3))**Rational(2, 5)) == (x**Rational(3))**Rational(2, 5) a = Symbol('a', real=True) b = Symbol('b', real=True) assert (a**2)**b == (abs(a)**b)**2 assert sqrt(1/a) != 1/sqrt(a) # e.g. for a = -1 assert (a**3)**Rational(1, 3) != a assert (x**a)**b != x**(a*b) # e.g. x = -1, a=2, b=1/2 assert (x**.5)**b == x**(.5*b) assert (x**.5)**.5 == x**.25 assert (x**2.5)**.5 != x**1.25 # e.g. for x = 5*I k = Symbol('k', integer=True) m = Symbol('m', integer=True) assert (x**k)**m == x**(k*m) assert Number(5)**Rational(2, 3) == Number(25)**Rational(1, 3) assert (x**.5)**2 == x**1.0 assert (x**2)**k == (x**k)**2 == x**(2*k) a = Symbol('a', positive=True) assert (a**3)**Rational(2, 5) == a**Rational(6, 5) assert (a**2)**b == (a**b)**2 assert (a**Rational(2, 3))**x == a**(x*Rational(2, 3)) != (a**x)**Rational(2, 3) def test_issue_3866(): assert --sqrt(sqrt(5) - 1) == sqrt(sqrt(5) - 1) def test_negative_one(): x = Symbol('x', complex=True) y = Symbol('y', complex=True) assert 1/x**y == x**(-y) def test_issue_4362(): neg = Symbol('neg', negative=True) nonneg = Symbol('nonneg', nonnegative=True) any = Symbol('any') num, den = sqrt(1/neg).as_numer_denom() assert num == sqrt(-1) assert den == sqrt(-neg) num, den = sqrt(1/nonneg).as_numer_denom() assert num == 1 assert den == sqrt(nonneg) num, den = sqrt(1/any).as_numer_denom() assert num == sqrt(1/any) assert den == 1 def eqn(num, den, pow): return (num/den)**pow npos = 1 nneg = -1 dpos = 2 - sqrt(3) dneg = 1 - sqrt(3) assert dpos > 0 and dneg < 0 and npos > 0 and nneg < 0 # pos or neg integer eq = eqn(npos, dpos, 2) assert eq.is_Pow and eq.as_numer_denom() == (1, dpos**2) eq = eqn(npos, dneg, 2) assert eq.is_Pow and eq.as_numer_denom() == (1, dneg**2) eq = eqn(nneg, dpos, 2) assert eq.is_Pow and eq.as_numer_denom() == (1, dpos**2) eq = eqn(nneg, dneg, 2) assert eq.is_Pow and eq.as_numer_denom() == (1, dneg**2) eq = eqn(npos, dpos, -2) assert eq.is_Pow and eq.as_numer_denom() == (dpos**2, 1) eq = eqn(npos, dneg, -2) assert eq.is_Pow and eq.as_numer_denom() == (dneg**2, 1) eq = eqn(nneg, dpos, -2) assert eq.is_Pow and eq.as_numer_denom() == (dpos**2, 1) eq = eqn(nneg, dneg, -2) assert eq.is_Pow and eq.as_numer_denom() == (dneg**2, 1) # pos or neg rational pow = S.Half eq = eqn(npos, dpos, pow) assert eq.is_Pow and eq.as_numer_denom() == (npos**pow, dpos**pow) eq = eqn(npos, dneg, pow) assert eq.is_Pow is False and eq.as_numer_denom() == ((-npos)**pow, (-dneg)**pow) eq = eqn(nneg, dpos, pow) assert not eq.is_Pow or eq.as_numer_denom() == (nneg**pow, dpos**pow) eq = eqn(nneg, dneg, pow) assert eq.is_Pow and eq.as_numer_denom() == ((-nneg)**pow, (-dneg)**pow) eq = eqn(npos, dpos, -pow) assert eq.is_Pow and eq.as_numer_denom() == (dpos**pow, npos**pow) eq = eqn(npos, dneg, -pow) assert eq.is_Pow is False and eq.as_numer_denom() == (-(-npos)**pow*(-dneg)**pow, npos) eq = eqn(nneg, dpos, -pow) assert not eq.is_Pow or eq.as_numer_denom() == (dpos**pow, nneg**pow) eq = eqn(nneg, dneg, -pow) assert eq.is_Pow and eq.as_numer_denom() == ((-dneg)**pow, (-nneg)**pow) # unknown exponent pow = 2*any eq = eqn(npos, dpos, pow) assert eq.is_Pow and eq.as_numer_denom() == (npos**pow, dpos**pow) eq = eqn(npos, dneg, pow) assert eq.is_Pow and eq.as_numer_denom() == ((-npos)**pow, (-dneg)**pow) eq = eqn(nneg, dpos, pow) assert eq.is_Pow and eq.as_numer_denom() == (nneg**pow, dpos**pow) eq = eqn(nneg, dneg, pow) assert eq.is_Pow and eq.as_numer_denom() == ((-nneg)**pow, (-dneg)**pow) eq = eqn(npos, dpos, -pow) assert eq.as_numer_denom() == (dpos**pow, npos**pow) eq = eqn(npos, dneg, -pow) assert eq.is_Pow and eq.as_numer_denom() == ((-dneg)**pow, (-npos)**pow) eq = eqn(nneg, dpos, -pow) assert eq.is_Pow and eq.as_numer_denom() == (dpos**pow, nneg**pow) eq = eqn(nneg, dneg, -pow) assert eq.is_Pow and eq.as_numer_denom() == ((-dneg)**pow, (-nneg)**pow) x = Symbol('x') y = Symbol('y') assert ((1/(1 + x/3))**(-S.One)).as_numer_denom() == (3 + x, 3) notp = Symbol('notp', positive=False) # not positive does not imply real b = ((1 + x/notp)**-2) assert (b**(-y)).as_numer_denom() == (1, b**y) assert (b**(-S.One)).as_numer_denom() == ((notp + x)**2, notp**2) nonp = Symbol('nonp', nonpositive=True) assert (((1 + x/nonp)**-2)**(-S.One)).as_numer_denom() == ((-nonp - x)**2, nonp**2) n = Symbol('n', negative=True) assert (x**n).as_numer_denom() == (1, x**-n) assert sqrt(1/n).as_numer_denom() == (S.ImaginaryUnit, sqrt(-n)) n = Symbol('0 or neg', nonpositive=True) # if x and n are split up without negating each term and n is negative # then the answer might be wrong; if n is 0 it won't matter since # 1/oo and 1/zoo are both zero as is sqrt(0)/sqrt(-x) unless x is also # zero (in which case the negative sign doesn't matter): # 1/sqrt(1/-1) = -I but sqrt(-1)/sqrt(1) = I assert (1/sqrt(x/n)).as_numer_denom() == (sqrt(-n), sqrt(-x)) c = Symbol('c', complex=True) e = sqrt(1/c) assert e.as_numer_denom() == (e, 1) i = Symbol('i', integer=True) assert ((1 + x/y)**i).as_numer_denom() == ((x + y)**i, y**i) def test_Pow_Expr_args(): x = Symbol('x') bases = [Basic(), Poly(x, x), FiniteSet(x)] for base in bases: with warns_deprecated_sympy(): Pow(base, S.One) def test_Pow_signs(): """Cf. issues 4595 and 5250""" x = Symbol('x') y = Symbol('y') n = Symbol('n', even=True) assert (3 - y)**2 != (y - 3)**2 assert (3 - y)**n != (y - 3)**n assert (-3 + y - x)**2 != (3 - y + x)**2 assert (y - 3)**3 != -(3 - y)**3 def test_power_with_noncommutative_mul_as_base(): x = Symbol('x', commutative=False) y = Symbol('y', commutative=False) assert not (x*y)**3 == x**3*y**3 assert (2*x*y)**3 == 8*(x*y)**3 @_both_exp_pow def test_power_rewrite_exp(): assert (I**I).rewrite(exp) == exp(-pi/2) expr = (2 + 3*I)**(4 + 5*I) assert expr.rewrite(exp) == exp((4 + 5*I)*(log(sqrt(13)) + I*atan(Rational(3, 2)))) assert expr.rewrite(exp).expand() == \ 169*exp(5*I*log(13)/2)*exp(4*I*atan(Rational(3, 2)))*exp(-5*atan(Rational(3, 2))) assert ((6 + 7*I)**5).rewrite(exp) == 7225*sqrt(85)*exp(5*I*atan(Rational(7, 6))) expr = 5**(6 + 7*I) assert expr.rewrite(exp) == exp((6 + 7*I)*log(5)) assert expr.rewrite(exp).expand() == 15625*exp(7*I*log(5)) assert Pow(123, 789, evaluate=False).rewrite(exp) == 123**789 assert (1**I).rewrite(exp) == 1**I assert (0**I).rewrite(exp) == 0**I expr = (-2)**(2 + 5*I) assert expr.rewrite(exp) == exp((2 + 5*I)*(log(2) + I*pi)) assert expr.rewrite(exp).expand() == 4*exp(-5*pi)*exp(5*I*log(2)) assert ((-2)**S(-5)).rewrite(exp) == (-2)**S(-5) x, y = symbols('x y') assert (x**y).rewrite(exp) == exp(y*log(x)) if global_parameters.exp_is_pow: assert (7**x).rewrite(exp) == Pow(S.Exp1, x*log(7), evaluate=False) else: assert (7**x).rewrite(exp) == exp(x*log(7), evaluate=False) assert ((2 + 3*I)**x).rewrite(exp) == exp(x*(log(sqrt(13)) + I*atan(Rational(3, 2)))) assert (y**(5 + 6*I)).rewrite(exp) == exp(log(y)*(5 + 6*I)) assert all((1/func(x)).rewrite(exp) == 1/(func(x).rewrite(exp)) for func in (sin, cos, tan, sec, csc, sinh, cosh, tanh)) def test_zero(): x = Symbol('x') y = Symbol('y') assert 0**x != 0 assert 0**(2*x) == 0**x assert 0**(1.0*x) == 0**x assert 0**(2.0*x) == 0**x assert (0**(2 - x)).as_base_exp() == (0, 2 - x) assert 0**(x - 2) != S.Infinity**(2 - x) assert 0**(2*x*y) == 0**(x*y) assert 0**(-2*x*y) == S.ComplexInfinity**(x*y) #Test issue 19572 assert 0 ** -oo is zoo assert power(0, -oo) is zoo def test_pow_as_base_exp(): x = Symbol('x') assert (S.Infinity**(2 - x)).as_base_exp() == (S.Infinity, 2 - x) assert (S.Infinity**(x - 2)).as_base_exp() == (S.Infinity, x - 2) p = S.Half**x assert p.base, p.exp == p.as_base_exp() == (S(2), -x) # issue 8344: assert Pow(1, 2, evaluate=False).as_base_exp() == (S.One, S(2)) def test_nseries(): x = Symbol('x') assert sqrt(I*x - 1)._eval_nseries(x, 4, None, 1) == I + x/2 + I*x**2/8 - x**3/16 + O(x**4) assert sqrt(I*x - 1)._eval_nseries(x, 4, None, -1) == -I - x/2 - I*x**2/8 + x**3/16 + O(x**4) assert cbrt(I*x - 1)._eval_nseries(x, 4, None, 1) == (-1)**(S(1)/3) - (-1)**(S(5)/6)*x/3 + \ (-1)**(S(1)/3)*x**2/9 + 5*(-1)**(S(5)/6)*x**3/81 + O(x**4) assert cbrt(I*x - 1)._eval_nseries(x, 4, None, -1) == (-1)**(S(1)/3)*exp(-2*I*pi/3) - \ (-1)**(S(5)/6)*x*exp(-2*I*pi/3)/3 + (-1)**(S(1)/3)*x**2*exp(-2*I*pi/3)/9 + \ 5*(-1)**(S(5)/6)*x**3*exp(-2*I*pi/3)/81 + O(x**4) assert (1 / (exp(-1/x) + 1/x))._eval_nseries(x, 2, None) == -x**2*exp(-1/x) + x def test_issue_6100_12942_4473(): x = Symbol('x') y = Symbol('y') assert x**1.0 != x assert x != x**1.0 assert True != x**1.0 assert x**1.0 is not True assert x is not True assert x*y != (x*y)**1.0 # Pow != Symbol assert (x**1.0)**1.0 != x assert (x**1.0)**2.0 != x**2 b = Expr() assert Pow(b, 1.0, evaluate=False) != b # if the following gets distributed as a Mul (x**1.0*y**1.0 then # __eq__ methods could be added to Symbol and Pow to detect the # power-of-1.0 case. assert ((x*y)**1.0).func is Pow def test_issue_6208(): from sympy import root assert sqrt(33**(I*Rational(9, 10))) == -33**(I*Rational(9, 20)) assert root((6*I)**(2*I), 3).as_base_exp()[1] == Rational(1, 3) # != 2*I/3 assert root((6*I)**(I/3), 3).as_base_exp()[1] == I/9 assert sqrt(exp(3*I)) == exp(I*Rational(3, 2)) assert sqrt(-sqrt(3)*(1 + 2*I)) == sqrt(sqrt(3))*sqrt(-1 - 2*I) assert sqrt(exp(5*I)) == -exp(I*Rational(5, 2)) assert root(exp(5*I), 3).exp == Rational(1, 3) def test_issue_6990(): x = Symbol('x') a = Symbol('a') b = Symbol('b') assert (sqrt(a + b*x + x**2)).series(x, 0, 3).removeO() == \ sqrt(a) + x**2*(1/(2*sqrt(a)) - b**2/(8*a**(S(3)/2))) + b*x/(2*sqrt(a)) def test_issue_6068(): x = Symbol('x') assert sqrt(sin(x)).series(x, 0, 7) == \ sqrt(x) - x**Rational(5, 2)/12 + x**Rational(9, 2)/1440 - \ x**Rational(13, 2)/24192 + O(x**7) assert sqrt(sin(x)).series(x, 0, 9) == \ sqrt(x) - x**Rational(5, 2)/12 + x**Rational(9, 2)/1440 - \ x**Rational(13, 2)/24192 - 67*x**Rational(17, 2)/29030400 + O(x**9) assert sqrt(sin(x**3)).series(x, 0, 19) == \ x**Rational(3, 2) - x**Rational(15, 2)/12 + x**Rational(27, 2)/1440 + O(x**19) assert sqrt(sin(x**3)).series(x, 0, 20) == \ x**Rational(3, 2) - x**Rational(15, 2)/12 + x**Rational(27, 2)/1440 - \ x**Rational(39, 2)/24192 + O(x**20) def test_issue_6782(): x = Symbol('x') assert sqrt(sin(x**3)).series(x, 0, 7) == x**Rational(3, 2) + O(x**7) assert sqrt(sin(x**4)).series(x, 0, 3) == x**2 + O(x**3) def test_issue_6653(): x = Symbol('x') assert (1 / sqrt(1 + sin(x**2))).series(x, 0, 3) == 1 - x**2/2 + O(x**3) def test_issue_6429(): x = Symbol('x') c = Symbol('c') f = (c**2 + x)**(0.5) assert f.series(x, x0=0, n=1) == (c**2)**0.5 + O(x) assert f.taylor_term(0, x) == (c**2)**0.5 assert f.taylor_term(1, x) == 0.5*x*(c**2)**(-0.5) assert f.taylor_term(2, x) == -0.125*x**2*(c**2)**(-1.5) def test_issue_7638(): f = pi/log(sqrt(2)) assert ((1 + I)**(I*f/2))**0.3 == (1 + I)**(0.15*I*f) # if 1/3 -> 1.0/3 this should fail since it cannot be shown that the # sign will be +/-1; for the previous "small arg" case, it didn't matter # that this could not be proved assert (1 + I)**(4*I*f) == ((1 + I)**(12*I*f))**Rational(1, 3) assert (((1 + I)**(I*(1 + 7*f)))**Rational(1, 3)).exp == Rational(1, 3) r = symbols('r', real=True) assert sqrt(r**2) == abs(r) assert cbrt(r**3) != r assert sqrt(Pow(2*I, 5*S.Half)) != (2*I)**Rational(5, 4) p = symbols('p', positive=True) assert cbrt(p**2) == p**Rational(2, 3) assert NS(((0.2 + 0.7*I)**(0.7 + 1.0*I))**(0.5 - 0.1*I), 1) == '0.4 + 0.2*I' assert sqrt(1/(1 + I)) == sqrt(1 - I)/sqrt(2) # or 1/sqrt(1 + I) e = 1/(1 - sqrt(2)) assert sqrt(e) == I/sqrt(-1 + sqrt(2)) assert e**Rational(-1, 2) == -I*sqrt(-1 + sqrt(2)) assert sqrt((cos(1)**2 + sin(1)**2 - 1)**(3 + I)).exp in [S.Half, Rational(3, 2) + I/2] assert sqrt(r**Rational(4, 3)) != r**Rational(2, 3) assert sqrt((p + I)**Rational(4, 3)) == (p + I)**Rational(2, 3) assert sqrt((p - p**2*I)**2) == p - p**2*I assert sqrt((p + r*I)**2) != p + r*I e = (1 + I/5) assert sqrt(e**5) == e**(5*S.Half) assert sqrt(e**6) == e**3 assert sqrt((1 + I*r)**6) != (1 + I*r)**3 def test_issue_8582(): assert 1**oo is nan assert 1**(-oo) is nan assert 1**zoo is nan assert 1**(oo + I) is nan assert 1**(1 + I*oo) is nan assert 1**(oo + I*oo) is nan def test_issue_8650(): n = Symbol('n', integer=True, nonnegative=True) assert (n**n).is_positive is True x = 5*n + 5 assert (x**(5*(n + 1))).is_positive is True def test_issue_13914(): b = Symbol('b') assert (-1)**zoo is nan assert 2**zoo is nan assert (S.Half)**(1 + zoo) is nan assert I**(zoo + I) is nan assert b**(I + zoo) is nan def test_better_sqrt(): n = Symbol('n', integer=True, nonnegative=True) assert sqrt(3 + 4*I) == 2 + I assert sqrt(3 - 4*I) == 2 - I assert sqrt(-3 - 4*I) == 1 - 2*I assert sqrt(-3 + 4*I) == 1 + 2*I assert sqrt(32 + 24*I) == 6 + 2*I assert sqrt(32 - 24*I) == 6 - 2*I assert sqrt(-32 - 24*I) == 2 - 6*I assert sqrt(-32 + 24*I) == 2 + 6*I # triple (3, 4, 5): # parity of 3 matches parity of 5 and # den, 4, is a square assert sqrt((3 + 4*I)/4) == 1 + I/2 # triple (8, 15, 17) # parity of 8 doesn't match parity of 17 but # den/2, 8/2, is a square assert sqrt((8 + 15*I)/8) == (5 + 3*I)/4 # handle the denominator assert sqrt((3 - 4*I)/25) == (2 - I)/5 assert sqrt((3 - 4*I)/26) == (2 - I)/sqrt(26) # mul # issue #12739 assert sqrt((3 + 4*I)/(3 - 4*I)) == (3 + 4*I)/5 assert sqrt(2/(3 + 4*I)) == sqrt(2)/5*(2 - I) assert sqrt(n/(3 + 4*I)).subs(n, 2) == sqrt(2)/5*(2 - I) assert sqrt(-2/(3 + 4*I)) == sqrt(2)/5*(1 + 2*I) assert sqrt(-n/(3 + 4*I)).subs(n, 2) == sqrt(2)/5*(1 + 2*I) # power assert sqrt(1/(3 + I*4)) == (2 - I)/5 assert sqrt(1/(3 - I)) == sqrt(10)*sqrt(3 + I)/10 # symbolic i = symbols('i', imaginary=True) assert sqrt(3/i) == Mul(sqrt(3), 1/sqrt(i), evaluate=False) # multiples of 1/2; don't make this too automatic assert sqrt(3 + 4*I)**3 == (2 + I)**3 assert Pow(3 + 4*I, Rational(3, 2)) == 2 + 11*I assert Pow(6 + 8*I, Rational(3, 2)) == 2*sqrt(2)*(2 + 11*I) n, d = (3 + 4*I), (3 - 4*I)**3 a = n/d assert a.args == (1/d, n) eq = sqrt(a) assert eq.args == (a, S.Half) assert expand_multinomial(eq) == sqrt((-117 + 44*I)*(3 + 4*I))/125 assert eq.expand() == (7 - 24*I)/125 # issue 12775 # pos im part assert sqrt(2*I) == (1 + I) assert sqrt(2*9*I) == Mul(3, 1 + I, evaluate=False) assert Pow(2*I, 3*S.Half) == (1 + I)**3 # neg im part assert sqrt(-I/2) == Mul(S.Half, 1 - I, evaluate=False) # fractional im part assert Pow(Rational(-9, 2)*I, Rational(3, 2)) == 27*(1 - I)**3/8 def test_issue_2993(): x = Symbol('x') assert str((2.3*x - 4)**0.3) == '1.5157165665104*(0.575*x - 1)**0.3' assert str((2.3*x + 4)**0.3) == '1.5157165665104*(0.575*x + 1)**0.3' assert str((-2.3*x + 4)**0.3) == '1.5157165665104*(1 - 0.575*x)**0.3' assert str((-2.3*x - 4)**0.3) == '1.5157165665104*(-0.575*x - 1)**0.3' assert str((2.3*x - 2)**0.3) == '1.28386201800527*(x - 0.869565217391304)**0.3' assert str((-2.3*x - 2)**0.3) == '1.28386201800527*(-x - 0.869565217391304)**0.3' assert str((-2.3*x + 2)**0.3) == '1.28386201800527*(0.869565217391304 - x)**0.3' assert str((2.3*x + 2)**0.3) == '1.28386201800527*(x + 0.869565217391304)**0.3' assert str((2.3*x - 4)**Rational(1, 3)) == '2**(2/3)*(0.575*x - 1)**(1/3)' eq = (2.3*x + 4) assert eq**2 == 16*(0.575*x + 1)**2 assert (1/eq).args == (eq, -1) # don't change trivial power # issue 17735 q=.5*exp(x) - .5*exp(-x) + 0.1 assert int((q**2).subs(x, 1)) == 1 # issue 17756 y = Symbol('y') assert len(sqrt(x/(x + y)**2 + Float('0.008', 30)).subs(y, pi.n(25)).atoms(Float)) == 2 # issue 17756 a, b, c, d, e, f, g = symbols('a:g') expr = sqrt(1 + a*(c**4 + g*d - 2*g*e - f*(-g + d))**2/ (c**3*b**2*(d - 3*e + 2*f)**2))/2 r = [ (a, N('0.0170992456333788667034850458615', 30)), (b, N('0.0966594956075474769169134801223', 30)), (c, N('0.390911862903463913632151616184', 30)), (d, N('0.152812084558656566271750185933', 30)), (e, N('0.137562344465103337106561623432', 30)), (f, N('0.174259178881496659302933610355', 30)), (g, N('0.220745448491223779615401870086', 30))] tru = expr.n(30, subs=dict(r)) seq = expr.subs(r) # although `tru` is the right way to evaluate # expr with numerical values, `seq` will have # significant loss of precision if extraction of # the largest coefficient of a power's base's terms # is done improperly assert seq == tru def test_issue_17450(): assert (erf(cosh(1)**7)**I).is_real is None assert (erf(cosh(1)**7)**I).is_imaginary is False assert (Pow(exp(1+sqrt(2)), ((1-sqrt(2))*I*pi), evaluate=False)).is_real is None assert ((-10)**(10*I*pi/3)).is_real is False assert ((-5)**(4*I*pi)).is_real is False def test_issue_18190(): assert sqrt(1 / tan(1 + I)) == 1 / sqrt(tan(1 + I)) def test_issue_14815(): x = Symbol('x', real=True) assert sqrt(x).is_extended_negative is False x = Symbol('x', real=False) assert sqrt(x).is_extended_negative is None x = Symbol('x', complex=True) assert sqrt(x).is_extended_negative is False x = Symbol('x', extended_real=True) assert sqrt(x).is_extended_negative is False assert sqrt(zoo, evaluate=False).is_extended_negative is None assert sqrt(nan, evaluate=False).is_extended_negative is None def test_issue_18509(): assert unchanged(Mul, oo, 1/pi**oo) assert (1/pi**oo).is_extended_positive == False def test_issue_18762(): e, p = symbols('e p') g0 = sqrt(1 + e**2 - 2*e*cos(p)) assert len(g0.series(e, 1, 3).args) == 4 def test_power_dispatcher(): class NewBase(Expr): pass class NewPow(NewBase, Pow): pass a, b = Symbol('a'), NewBase() @power.register(Expr, NewBase) @power.register(NewBase, Expr) @power.register(NewBase, NewBase) def _(a, b): return NewPow(a, b) # Pow called as fallback assert power(2, 3) == 8*S.One assert power(a, 2) == Pow(a, 2) assert power(a, a) == Pow(a, a) # NewPow called by dispatch assert power(a, b) == NewPow(a, b) assert power(b, a) == NewPow(b, a) assert power(b, b) == NewPow(b, b) def test_powers_of_I(): assert [sqrt(I)**i for i in range(13)] == [ 1, sqrt(I), I, sqrt(I)**3, -1, -sqrt(I), -I, -sqrt(I)**3, 1, sqrt(I), I, sqrt(I)**3, -1] assert sqrt(I)**(S(9)/2) == -I**(S(1)/4)
c409fc88aa0c2ae8ab3327c8cdc7ace3127cd44d78075eefdfccd7f4eb3b6848
from sympy import I, sqrt, log, exp, sin, asin, factorial, Mod, pi, oo from sympy.core import Symbol, S, Rational, Integer, Dummy, Wild, Pow from sympy.core.assumptions import (assumptions, check_assumptions, failing_assumptions, common_assumptions) from sympy.core.facts import InconsistentAssumptions from sympy import simplify from sympy.testing.pytest import raises, XFAIL def test_symbol_unset(): x = Symbol('x', real=True, integer=True) assert x.is_real is True assert x.is_integer is True assert x.is_imaginary is False assert x.is_noninteger is False assert x.is_number is False def test_zero(): z = Integer(0) assert z.is_commutative is True assert z.is_integer is True assert z.is_rational is True assert z.is_algebraic is True assert z.is_transcendental is False assert z.is_real is True assert z.is_complex is True assert z.is_noninteger is False assert z.is_irrational is False assert z.is_imaginary is False assert z.is_positive is False assert z.is_negative is False assert z.is_nonpositive is True assert z.is_nonnegative is True assert z.is_even is True assert z.is_odd is False assert z.is_finite is True assert z.is_infinite is False assert z.is_comparable is True assert z.is_prime is False assert z.is_composite is False assert z.is_number is True def test_one(): z = Integer(1) assert z.is_commutative is True assert z.is_integer is True assert z.is_rational is True assert z.is_algebraic is True assert z.is_transcendental is False assert z.is_real is True assert z.is_complex is True assert z.is_noninteger is False assert z.is_irrational is False assert z.is_imaginary is False assert z.is_positive is True assert z.is_negative is False assert z.is_nonpositive is False assert z.is_nonnegative is True assert z.is_even is False assert z.is_odd is True assert z.is_finite is True assert z.is_infinite is False assert z.is_comparable is True assert z.is_prime is False assert z.is_number is True assert z.is_composite is False # issue 8807 def test_negativeone(): z = Integer(-1) assert z.is_commutative is True assert z.is_integer is True assert z.is_rational is True assert z.is_algebraic is True assert z.is_transcendental is False assert z.is_real is True assert z.is_complex is True assert z.is_noninteger is False assert z.is_irrational is False assert z.is_imaginary is False assert z.is_positive is False assert z.is_negative is True assert z.is_nonpositive is True assert z.is_nonnegative is False assert z.is_even is False assert z.is_odd is True assert z.is_finite is True assert z.is_infinite is False assert z.is_comparable is True assert z.is_prime is False assert z.is_composite is False assert z.is_number is True def test_infinity(): oo = S.Infinity assert oo.is_commutative is True assert oo.is_integer is False assert oo.is_rational is False assert oo.is_algebraic is False assert oo.is_transcendental is False assert oo.is_extended_real is True assert oo.is_real is False assert oo.is_complex is False assert oo.is_noninteger is True assert oo.is_irrational is False assert oo.is_imaginary is False assert oo.is_nonzero is False assert oo.is_positive is False assert oo.is_negative is False assert oo.is_nonpositive is False assert oo.is_nonnegative is False assert oo.is_extended_nonzero is True assert oo.is_extended_positive is True assert oo.is_extended_negative is False assert oo.is_extended_nonpositive is False assert oo.is_extended_nonnegative is True assert oo.is_even is False assert oo.is_odd is False assert oo.is_finite is False assert oo.is_infinite is True assert oo.is_comparable is True assert oo.is_prime is False assert oo.is_composite is False assert oo.is_number is True def test_neg_infinity(): mm = S.NegativeInfinity assert mm.is_commutative is True assert mm.is_integer is False assert mm.is_rational is False assert mm.is_algebraic is False assert mm.is_transcendental is False assert mm.is_extended_real is True assert mm.is_real is False assert mm.is_complex is False assert mm.is_noninteger is True assert mm.is_irrational is False assert mm.is_imaginary is False assert mm.is_nonzero is False assert mm.is_positive is False assert mm.is_negative is False assert mm.is_nonpositive is False assert mm.is_nonnegative is False assert mm.is_extended_nonzero is True assert mm.is_extended_positive is False assert mm.is_extended_negative is True assert mm.is_extended_nonpositive is True assert mm.is_extended_nonnegative is False assert mm.is_even is False assert mm.is_odd is False assert mm.is_finite is False assert mm.is_infinite is True assert mm.is_comparable is True assert mm.is_prime is False assert mm.is_composite is False assert mm.is_number is True def test_zoo(): zoo = S.ComplexInfinity assert zoo.is_complex is False assert zoo.is_real is False assert zoo.is_prime is False def test_nan(): nan = S.NaN assert nan.is_commutative is True assert nan.is_integer is None assert nan.is_rational is None assert nan.is_algebraic is None assert nan.is_transcendental is None assert nan.is_real is None assert nan.is_complex is None assert nan.is_noninteger is None assert nan.is_irrational is None assert nan.is_imaginary is None assert nan.is_positive is None assert nan.is_negative is None assert nan.is_nonpositive is None assert nan.is_nonnegative is None assert nan.is_even is None assert nan.is_odd is None assert nan.is_finite is None assert nan.is_infinite is None assert nan.is_comparable is False assert nan.is_prime is None assert nan.is_composite is None assert nan.is_number is True def test_pos_rational(): r = Rational(3, 4) assert r.is_commutative is True assert r.is_integer is False assert r.is_rational is True assert r.is_algebraic is True assert r.is_transcendental is False assert r.is_real is True assert r.is_complex is True assert r.is_noninteger is True assert r.is_irrational is False assert r.is_imaginary is False assert r.is_positive is True assert r.is_negative is False assert r.is_nonpositive is False assert r.is_nonnegative is True assert r.is_even is False assert r.is_odd is False assert r.is_finite is True assert r.is_infinite is False assert r.is_comparable is True assert r.is_prime is False assert r.is_composite is False r = Rational(1, 4) assert r.is_nonpositive is False assert r.is_positive is True assert r.is_negative is False assert r.is_nonnegative is True r = Rational(5, 4) assert r.is_negative is False assert r.is_positive is True assert r.is_nonpositive is False assert r.is_nonnegative is True r = Rational(5, 3) assert r.is_nonnegative is True assert r.is_positive is True assert r.is_negative is False assert r.is_nonpositive is False def test_neg_rational(): r = Rational(-3, 4) assert r.is_positive is False assert r.is_nonpositive is True assert r.is_negative is True assert r.is_nonnegative is False r = Rational(-1, 4) assert r.is_nonpositive is True assert r.is_positive is False assert r.is_negative is True assert r.is_nonnegative is False r = Rational(-5, 4) assert r.is_negative is True assert r.is_positive is False assert r.is_nonpositive is True assert r.is_nonnegative is False r = Rational(-5, 3) assert r.is_nonnegative is False assert r.is_positive is False assert r.is_negative is True assert r.is_nonpositive is True def test_pi(): z = S.Pi assert z.is_commutative is True assert z.is_integer is False assert z.is_rational is False assert z.is_algebraic is False assert z.is_transcendental is True assert z.is_real is True assert z.is_complex is True assert z.is_noninteger is True assert z.is_irrational is True assert z.is_imaginary is False assert z.is_positive is True assert z.is_negative is False assert z.is_nonpositive is False assert z.is_nonnegative is True assert z.is_even is False assert z.is_odd is False assert z.is_finite is True assert z.is_infinite is False assert z.is_comparable is True assert z.is_prime is False assert z.is_composite is False def test_E(): z = S.Exp1 assert z.is_commutative is True assert z.is_integer is False assert z.is_rational is False assert z.is_algebraic is False assert z.is_transcendental is True assert z.is_real is True assert z.is_complex is True assert z.is_noninteger is True assert z.is_irrational is True assert z.is_imaginary is False assert z.is_positive is True assert z.is_negative is False assert z.is_nonpositive is False assert z.is_nonnegative is True assert z.is_even is False assert z.is_odd is False assert z.is_finite is True assert z.is_infinite is False assert z.is_comparable is True assert z.is_prime is False assert z.is_composite is False def test_I(): z = S.ImaginaryUnit assert z.is_commutative is True assert z.is_integer is False assert z.is_rational is False assert z.is_algebraic is True assert z.is_transcendental is False assert z.is_real is False assert z.is_complex is True assert z.is_noninteger is False assert z.is_irrational is False assert z.is_imaginary is True assert z.is_positive is False assert z.is_negative is False assert z.is_nonpositive is False assert z.is_nonnegative is False assert z.is_even is False assert z.is_odd is False assert z.is_finite is True assert z.is_infinite is False assert z.is_comparable is False assert z.is_prime is False assert z.is_composite is False def test_symbol_real_false(): # issue 3848 a = Symbol('a', real=False) assert a.is_real is False assert a.is_integer is False assert a.is_zero is False assert a.is_negative is False assert a.is_positive is False assert a.is_nonnegative is False assert a.is_nonpositive is False assert a.is_nonzero is False assert a.is_extended_negative is None assert a.is_extended_positive is None assert a.is_extended_nonnegative is None assert a.is_extended_nonpositive is None assert a.is_extended_nonzero is None def test_symbol_extended_real_false(): # issue 3848 a = Symbol('a', extended_real=False) assert a.is_real is False assert a.is_integer is False assert a.is_zero is False assert a.is_negative is False assert a.is_positive is False assert a.is_nonnegative is False assert a.is_nonpositive is False assert a.is_nonzero is False assert a.is_extended_negative is False assert a.is_extended_positive is False assert a.is_extended_nonnegative is False assert a.is_extended_nonpositive is False assert a.is_extended_nonzero is False def test_symbol_imaginary(): a = Symbol('a', imaginary=True) assert a.is_real is False assert a.is_integer is False assert a.is_negative is False assert a.is_positive is False assert a.is_nonnegative is False assert a.is_nonpositive is False assert a.is_zero is False assert a.is_nonzero is False # since nonzero -> real def test_symbol_zero(): x = Symbol('x', zero=True) assert x.is_positive is False assert x.is_nonpositive assert x.is_negative is False assert x.is_nonnegative assert x.is_zero is True # TODO Change to x.is_nonzero is None # See https://github.com/sympy/sympy/pull/9583 assert x.is_nonzero is False assert x.is_finite is True def test_symbol_positive(): x = Symbol('x', positive=True) assert x.is_positive is True assert x.is_nonpositive is False assert x.is_negative is False assert x.is_nonnegative is True assert x.is_zero is False assert x.is_nonzero is True def test_neg_symbol_positive(): x = -Symbol('x', positive=True) assert x.is_positive is False assert x.is_nonpositive is True assert x.is_negative is True assert x.is_nonnegative is False assert x.is_zero is False assert x.is_nonzero is True def test_symbol_nonpositive(): x = Symbol('x', nonpositive=True) assert x.is_positive is False assert x.is_nonpositive is True assert x.is_negative is None assert x.is_nonnegative is None assert x.is_zero is None assert x.is_nonzero is None def test_neg_symbol_nonpositive(): x = -Symbol('x', nonpositive=True) assert x.is_positive is None assert x.is_nonpositive is None assert x.is_negative is False assert x.is_nonnegative is True assert x.is_zero is None assert x.is_nonzero is None def test_symbol_falsepositive(): x = Symbol('x', positive=False) assert x.is_positive is False assert x.is_nonpositive is None assert x.is_negative is None assert x.is_nonnegative is None assert x.is_zero is None assert x.is_nonzero is None def test_symbol_falsepositive_mul(): # To test pull request 9379 # Explicit handling of arg.is_positive=False was added to Mul._eval_is_positive x = 2*Symbol('x', positive=False) assert x.is_positive is False # This was None before assert x.is_nonpositive is None assert x.is_negative is None assert x.is_nonnegative is None assert x.is_zero is None assert x.is_nonzero is None @XFAIL def test_symbol_infinitereal_mul(): ix = Symbol('ix', infinite=True, extended_real=True) assert (-ix).is_extended_positive is None def test_neg_symbol_falsepositive(): x = -Symbol('x', positive=False) assert x.is_positive is None assert x.is_nonpositive is None assert x.is_negative is False assert x.is_nonnegative is None assert x.is_zero is None assert x.is_nonzero is None def test_neg_symbol_falsenegative(): # To test pull request 9379 # Explicit handling of arg.is_negative=False was added to Mul._eval_is_positive x = -Symbol('x', negative=False) assert x.is_positive is False # This was None before assert x.is_nonpositive is None assert x.is_negative is None assert x.is_nonnegative is None assert x.is_zero is None assert x.is_nonzero is None def test_symbol_falsepositive_real(): x = Symbol('x', positive=False, real=True) assert x.is_positive is False assert x.is_nonpositive is True assert x.is_negative is None assert x.is_nonnegative is None assert x.is_zero is None assert x.is_nonzero is None def test_neg_symbol_falsepositive_real(): x = -Symbol('x', positive=False, real=True) assert x.is_positive is None assert x.is_nonpositive is None assert x.is_negative is False assert x.is_nonnegative is True assert x.is_zero is None assert x.is_nonzero is None def test_symbol_falsenonnegative(): x = Symbol('x', nonnegative=False) assert x.is_positive is False assert x.is_nonpositive is None assert x.is_negative is None assert x.is_nonnegative is False assert x.is_zero is False assert x.is_nonzero is None @XFAIL def test_neg_symbol_falsenonnegative(): x = -Symbol('x', nonnegative=False) assert x.is_positive is None assert x.is_nonpositive is False # this currently returns None assert x.is_negative is False # this currently returns None assert x.is_nonnegative is None assert x.is_zero is False # this currently returns None assert x.is_nonzero is True # this currently returns None def test_symbol_falsenonnegative_real(): x = Symbol('x', nonnegative=False, real=True) assert x.is_positive is False assert x.is_nonpositive is True assert x.is_negative is True assert x.is_nonnegative is False assert x.is_zero is False assert x.is_nonzero is True def test_neg_symbol_falsenonnegative_real(): x = -Symbol('x', nonnegative=False, real=True) assert x.is_positive is True assert x.is_nonpositive is False assert x.is_negative is False assert x.is_nonnegative is True assert x.is_zero is False assert x.is_nonzero is True def test_prime(): assert S.NegativeOne.is_prime is False assert S(-2).is_prime is False assert S(-4).is_prime is False assert S.Zero.is_prime is False assert S.One.is_prime is False assert S(2).is_prime is True assert S(17).is_prime is True assert S(4).is_prime is False def test_composite(): assert S.NegativeOne.is_composite is False assert S(-2).is_composite is False assert S(-4).is_composite is False assert S.Zero.is_composite is False assert S(2).is_composite is False assert S(17).is_composite is False assert S(4).is_composite is True x = Dummy(integer=True, positive=True, prime=False) assert x.is_composite is None # x could be 1 assert (x + 1).is_composite is None x = Dummy(positive=True, even=True, prime=False) assert x.is_integer is True assert x.is_composite is True def test_prime_symbol(): x = Symbol('x', prime=True) assert x.is_prime is True assert x.is_integer is True assert x.is_positive is True assert x.is_negative is False assert x.is_nonpositive is False assert x.is_nonnegative is True x = Symbol('x', prime=False) assert x.is_prime is False assert x.is_integer is None assert x.is_positive is None assert x.is_negative is None assert x.is_nonpositive is None assert x.is_nonnegative is None def test_symbol_noncommutative(): x = Symbol('x', commutative=True) assert x.is_complex is None x = Symbol('x', commutative=False) assert x.is_integer is False assert x.is_rational is False assert x.is_algebraic is False assert x.is_irrational is False assert x.is_real is False assert x.is_complex is False def test_other_symbol(): x = Symbol('x', integer=True) assert x.is_integer is True assert x.is_real is True assert x.is_finite is True x = Symbol('x', integer=True, nonnegative=True) assert x.is_integer is True assert x.is_nonnegative is True assert x.is_negative is False assert x.is_positive is None assert x.is_finite is True x = Symbol('x', integer=True, nonpositive=True) assert x.is_integer is True assert x.is_nonpositive is True assert x.is_positive is False assert x.is_negative is None assert x.is_finite is True x = Symbol('x', odd=True) assert x.is_odd is True assert x.is_even is False assert x.is_integer is True assert x.is_finite is True x = Symbol('x', odd=False) assert x.is_odd is False assert x.is_even is None assert x.is_integer is None assert x.is_finite is None x = Symbol('x', even=True) assert x.is_even is True assert x.is_odd is False assert x.is_integer is True assert x.is_finite is True x = Symbol('x', even=False) assert x.is_even is False assert x.is_odd is None assert x.is_integer is None assert x.is_finite is None x = Symbol('x', integer=True, nonnegative=True) assert x.is_integer is True assert x.is_nonnegative is True assert x.is_finite is True x = Symbol('x', integer=True, nonpositive=True) assert x.is_integer is True assert x.is_nonpositive is True assert x.is_finite is True x = Symbol('x', rational=True) assert x.is_real is True assert x.is_finite is True x = Symbol('x', rational=False) assert x.is_real is None assert x.is_finite is None x = Symbol('x', irrational=True) assert x.is_real is True assert x.is_finite is True x = Symbol('x', irrational=False) assert x.is_real is None assert x.is_finite is None with raises(AttributeError): x.is_real = False x = Symbol('x', algebraic=True) assert x.is_transcendental is False x = Symbol('x', transcendental=True) assert x.is_algebraic is False assert x.is_rational is False assert x.is_integer is False def test_issue_3825(): """catch: hash instability""" x = Symbol("x") y = Symbol("y") a1 = x + y a2 = y + x a2.is_comparable h1 = hash(a1) h2 = hash(a2) assert h1 == h2 def test_issue_4822(): z = (-1)**Rational(1, 3)*(1 - I*sqrt(3)) assert z.is_real in [True, None] def test_hash_vs_typeinfo(): """seemingly different typeinfo, but in fact equal""" # the following two are semantically equal x1 = Symbol('x', even=True) x2 = Symbol('x', integer=True, odd=False) assert hash(x1) == hash(x2) assert x1 == x2 def test_hash_vs_typeinfo_2(): """different typeinfo should mean !eq""" # the following two are semantically different x = Symbol('x') x1 = Symbol('x', even=True) assert x != x1 assert hash(x) != hash(x1) # This might fail with very low probability def test_hash_vs_eq(): """catch: different hash for equal objects""" a = 1 + S.Pi # important: do not fold it into a Number instance ha = hash(a) # it should be Add/Mul/... to trigger the bug a.is_positive # this uses .evalf() and deduces it is positive assert a.is_positive is True # be sure that hash stayed the same assert ha == hash(a) # now b should be the same expression b = a.expand(trig=True) hb = hash(b) assert a == b assert ha == hb def test_Add_is_pos_neg(): # these cover lines not covered by the rest of tests in core n = Symbol('n', extended_negative=True, infinite=True) nn = Symbol('n', extended_nonnegative=True, infinite=True) np = Symbol('n', extended_nonpositive=True, infinite=True) p = Symbol('p', extended_positive=True, infinite=True) r = Dummy(extended_real=True, finite=False) x = Symbol('x') xf = Symbol('xf', finite=True) assert (n + p).is_extended_positive is None assert (n + x).is_extended_positive is None assert (p + x).is_extended_positive is None assert (n + p).is_extended_negative is None assert (n + x).is_extended_negative is None assert (p + x).is_extended_negative is None assert (n + xf).is_extended_positive is False assert (p + xf).is_extended_positive is True assert (n + xf).is_extended_negative is True assert (p + xf).is_extended_negative is False assert (x - S.Infinity).is_extended_negative is None # issue 7798 # issue 8046, 16.2 assert (p + nn).is_extended_positive assert (n + np).is_extended_negative assert (p + r).is_extended_positive is None def test_Add_is_imaginary(): nn = Dummy(nonnegative=True) assert (I*nn + I).is_imaginary # issue 8046, 17 def test_Add_is_algebraic(): a = Symbol('a', algebraic=True) b = Symbol('a', algebraic=True) na = Symbol('na', algebraic=False) nb = Symbol('nb', algebraic=False) x = Symbol('x') assert (a + b).is_algebraic assert (na + nb).is_algebraic is None assert (a + na).is_algebraic is False assert (a + x).is_algebraic is None assert (na + x).is_algebraic is None def test_Mul_is_algebraic(): a = Symbol('a', algebraic=True) b = Symbol('b', algebraic=True) na = Symbol('na', algebraic=False) an = Symbol('an', algebraic=True, nonzero=True) nb = Symbol('nb', algebraic=False) x = Symbol('x') assert (a*b).is_algebraic is True assert (na*nb).is_algebraic is None assert (a*na).is_algebraic is None assert (an*na).is_algebraic is False assert (a*x).is_algebraic is None assert (na*x).is_algebraic is None def test_Pow_is_algebraic(): e = Symbol('e', algebraic=True) assert Pow(1, e, evaluate=False).is_algebraic assert Pow(0, e, evaluate=False).is_algebraic a = Symbol('a', algebraic=True) azf = Symbol('azf', algebraic=True, zero=False) na = Symbol('na', algebraic=False) ia = Symbol('ia', algebraic=True, irrational=True) ib = Symbol('ib', algebraic=True, irrational=True) r = Symbol('r', rational=True) x = Symbol('x') assert (a**2).is_algebraic is True assert (a**r).is_algebraic is None assert (azf**r).is_algebraic is True assert (a**x).is_algebraic is None assert (na**r).is_algebraic is None assert (ia**r).is_algebraic is True assert (ia**ib).is_algebraic is False assert (a**e).is_algebraic is None # Gelfond-Schneider constant: assert Pow(2, sqrt(2), evaluate=False).is_algebraic is False assert Pow(S.GoldenRatio, sqrt(3), evaluate=False).is_algebraic is False # issue 8649 t = Symbol('t', real=True, transcendental=True) n = Symbol('n', integer=True) assert (t**n).is_algebraic is None assert (t**n).is_integer is None assert (pi**3).is_algebraic is False r = Symbol('r', zero=True) assert (pi**r).is_algebraic is True def test_Mul_is_prime_composite(): x = Symbol('x', positive=True, integer=True) y = Symbol('y', positive=True, integer=True) assert (x*y).is_prime is None assert ( (x+1)*(y+1) ).is_prime is False assert ( (x+1)*(y+1) ).is_composite is True x = Symbol('x', positive=True) assert ( (x+1)*(y+1) ).is_prime is None assert ( (x+1)*(y+1) ).is_composite is None def test_Pow_is_pos_neg(): z = Symbol('z', real=True) w = Symbol('w', nonpositive=True) assert (S.NegativeOne**S(2)).is_positive is True assert (S.One**z).is_positive is True assert (S.NegativeOne**S(3)).is_positive is False assert (S.Zero**S.Zero).is_positive is True # 0**0 is 1 assert (w**S(3)).is_positive is False assert (w**S(2)).is_positive is None assert (I**2).is_positive is False assert (I**4).is_positive is True # tests emerging from #16332 issue p = Symbol('p', zero=True) q = Symbol('q', zero=False, real=True) j = Symbol('j', zero=False, even=True) x = Symbol('x', zero=True) y = Symbol('y', zero=True) assert (p**q).is_positive is False assert (p**q).is_negative is False assert (p**j).is_positive is False assert (x**y).is_positive is True # 0**0 assert (x**y).is_negative is False def test_Pow_is_prime_composite(): x = Symbol('x', positive=True, integer=True) y = Symbol('y', positive=True, integer=True) assert (x**y).is_prime is None assert ( x**(y+1) ).is_prime is False assert ( x**(y+1) ).is_composite is None assert ( (x+1)**(y+1) ).is_composite is True assert ( (-x-1)**(2*y) ).is_composite is True x = Symbol('x', positive=True) assert (x**y).is_prime is None def test_Mul_is_infinite(): x = Symbol('x') f = Symbol('f', finite=True) i = Symbol('i', infinite=True) z = Dummy(zero=True) nzf = Dummy(finite=True, zero=False) from sympy import Mul assert (x*f).is_finite is None assert (x*i).is_finite is None assert (f*i).is_finite is None assert (x*f*i).is_finite is None assert (z*i).is_finite is None assert (nzf*i).is_finite is False assert (z*f).is_finite is True assert Mul(0, f, evaluate=False).is_finite is True assert Mul(0, i, evaluate=False).is_finite is None assert (x*f).is_infinite is None assert (x*i).is_infinite is None assert (f*i).is_infinite is None assert (x*f*i).is_infinite is None assert (z*i).is_infinite is S.NaN.is_infinite assert (nzf*i).is_infinite is True assert (z*f).is_infinite is False assert Mul(0, f, evaluate=False).is_infinite is False assert Mul(0, i, evaluate=False).is_infinite is S.NaN.is_infinite def test_Add_is_infinite(): x = Symbol('x') f = Symbol('f', finite=True) i = Symbol('i', infinite=True) i2 = Symbol('i2', infinite=True) z = Dummy(zero=True) nzf = Dummy(finite=True, zero=False) from sympy import Add assert (x+f).is_finite is None assert (x+i).is_finite is None assert (f+i).is_finite is False assert (x+f+i).is_finite is None assert (z+i).is_finite is False assert (nzf+i).is_finite is False assert (z+f).is_finite is True assert (i+i2).is_finite is None assert Add(0, f, evaluate=False).is_finite is True assert Add(0, i, evaluate=False).is_finite is False assert (x+f).is_infinite is None assert (x+i).is_infinite is None assert (f+i).is_infinite is True assert (x+f+i).is_infinite is None assert (z+i).is_infinite is True assert (nzf+i).is_infinite is True assert (z+f).is_infinite is False assert (i+i2).is_infinite is None assert Add(0, f, evaluate=False).is_infinite is False assert Add(0, i, evaluate=False).is_infinite is True def test_special_is_rational(): i = Symbol('i', integer=True) i2 = Symbol('i2', integer=True) ni = Symbol('ni', integer=True, nonzero=True) r = Symbol('r', rational=True) rn = Symbol('r', rational=True, nonzero=True) nr = Symbol('nr', irrational=True) x = Symbol('x') assert sqrt(3).is_rational is False assert (3 + sqrt(3)).is_rational is False assert (3*sqrt(3)).is_rational is False assert exp(3).is_rational is False assert exp(ni).is_rational is False assert exp(rn).is_rational is False assert exp(x).is_rational is None assert exp(log(3), evaluate=False).is_rational is True assert log(exp(3), evaluate=False).is_rational is True assert log(3).is_rational is False assert log(ni + 1).is_rational is False assert log(rn + 1).is_rational is False assert log(x).is_rational is None assert (sqrt(3) + sqrt(5)).is_rational is None assert (sqrt(3) + S.Pi).is_rational is False assert (x**i).is_rational is None assert (i**i).is_rational is True assert (i**i2).is_rational is None assert (r**i).is_rational is None assert (r**r).is_rational is None assert (r**x).is_rational is None assert (nr**i).is_rational is None # issue 8598 assert (nr**Symbol('z', zero=True)).is_rational assert sin(1).is_rational is False assert sin(ni).is_rational is False assert sin(rn).is_rational is False assert sin(x).is_rational is None assert asin(r).is_rational is False assert sin(asin(3), evaluate=False).is_rational is True @XFAIL def test_issue_6275(): x = Symbol('x') # both zero or both Muls...but neither "change would be very appreciated. # This is similar to x/x => 1 even though if x = 0, it is really nan. assert isinstance(x*0, type(0*S.Infinity)) if 0*S.Infinity is S.NaN: b = Symbol('b', finite=None) assert (b*0).is_zero is None def test_sanitize_assumptions(): # issue 6666 for cls in (Symbol, Dummy, Wild): x = cls('x', real=1, positive=0) assert x.is_real is True assert x.is_positive is False assert cls('', real=True, positive=None).is_positive is None raises(ValueError, lambda: cls('', commutative=None)) raises(ValueError, lambda: Symbol._sanitize(dict(commutative=None))) def test_special_assumptions(): e = -3 - sqrt(5) + (-sqrt(10)/2 - sqrt(2)/2)**2 assert simplify(e < 0) is S.false assert simplify(e > 0) is S.false assert (e == 0) is False # it's not a literal 0 assert e.equals(0) is True def test_inconsistent(): # cf. issues 5795 and 5545 raises(InconsistentAssumptions, lambda: Symbol('x', real=True, commutative=False)) def test_issue_6631(): assert ((-1)**(I)).is_real is True assert ((-1)**(I*2)).is_real is True assert ((-1)**(I/2)).is_real is True assert ((-1)**(I*S.Pi)).is_real is True assert (I**(I + 2)).is_real is True def test_issue_2730(): assert (1/(1 + I)).is_real is False def test_issue_4149(): assert (3 + I).is_complex assert (3 + I).is_imaginary is False assert (3*I + S.Pi*I).is_imaginary # as Zero.is_imaginary is False, see issue 7649 y = Symbol('y', real=True) assert (3*I + S.Pi*I + y*I).is_imaginary is None p = Symbol('p', positive=True) assert (3*I + S.Pi*I + p*I).is_imaginary n = Symbol('n', negative=True) assert (-3*I - S.Pi*I + n*I).is_imaginary i = Symbol('i', imaginary=True) assert ([(i**a).is_imaginary for a in range(4)] == [False, True, False, True]) # tests from the PR #7887: e = S("-sqrt(3)*I/2 + 0.866025403784439*I") assert e.is_real is False assert e.is_imaginary def test_issue_2920(): n = Symbol('n', negative=True) assert sqrt(n).is_imaginary def test_issue_7899(): x = Symbol('x', real=True) assert (I*x).is_real is None assert ((x - I)*(x - 1)).is_zero is None assert ((x - I)*(x - 1)).is_real is None @XFAIL def test_issue_7993(): x = Dummy(integer=True) y = Dummy(noninteger=True) assert (x - y).is_zero is False def test_issue_8075(): raises(InconsistentAssumptions, lambda: Dummy(zero=True, finite=False)) raises(InconsistentAssumptions, lambda: Dummy(zero=True, infinite=True)) def test_issue_8642(): x = Symbol('x', real=True, integer=False) assert (x*2).is_integer is None, (x*2).is_integer def test_issues_8632_8633_8638_8675_8992(): p = Dummy(integer=True, positive=True) nn = Dummy(integer=True, nonnegative=True) assert (p - S.Half).is_positive assert (p - 1).is_nonnegative assert (nn + 1).is_positive assert (-p + 1).is_nonpositive assert (-nn - 1).is_negative prime = Dummy(prime=True) assert (prime - 2).is_nonnegative assert (prime - 3).is_nonnegative is None even = Dummy(positive=True, even=True) assert (even - 2).is_nonnegative p = Dummy(positive=True) assert (p/(p + 1) - 1).is_negative assert ((p + 2)**3 - S.Half).is_positive n = Dummy(negative=True) assert (n - 3).is_nonpositive def test_issue_9115_9150(): n = Dummy('n', integer=True, nonnegative=True) assert (factorial(n) >= 1) == True assert (factorial(n) < 1) == False assert factorial(n + 1).is_even is None assert factorial(n + 2).is_even is True assert factorial(n + 2) >= 2 def test_issue_9165(): z = Symbol('z', zero=True) f = Symbol('f', finite=False) assert 0/z is S.NaN assert 0*(1/z) is S.NaN assert 0*f is S.NaN def test_issue_10024(): x = Dummy('x') assert Mod(x, 2*pi).is_zero is None def test_issue_10302(): x = Symbol('x') r = Symbol('r', real=True) u = -(3*2**pi)**(1/pi) + 2*3**(1/pi) i = u + u*I assert i.is_real is None # w/o simplification this should fail assert (u + i).is_zero is None assert (1 + i).is_zero is False a = Dummy('a', zero=True) assert (a + I).is_zero is False assert (a + r*I).is_zero is None assert (a + I).is_imaginary assert (a + x + I).is_imaginary is None assert (a + r*I + I).is_imaginary is None def test_complex_reciprocal_imaginary(): assert (1 / (4 + 3*I)).is_imaginary is False def test_issue_16313(): x = Symbol('x', extended_real=False) k = Symbol('k', real=True) l = Symbol('l', real=True, zero=False) assert (-x).is_real is False assert (k*x).is_real is None # k can be zero also assert (l*x).is_real is False assert (l*x*x).is_real is None # since x*x can be a real number assert (-x).is_positive is False def test_issue_16579(): # extended_real -> finite | infinite x = Symbol('x', extended_real=True, infinite=False) y = Symbol('y', extended_real=True, finite=False) assert x.is_finite is True assert y.is_infinite is True # With PR 16978, complex now implies finite c = Symbol('c', complex=True) assert c.is_finite is True raises(InconsistentAssumptions, lambda: Dummy(complex=True, finite=False)) # Now infinite == !finite nf = Symbol('nf', finite=False) assert nf.is_infinite is True def test_issue_17556(): z = I*oo assert z.is_imaginary is False assert z.is_finite is False def test_assumptions_copy(): assert assumptions(Symbol('x'), dict(commutative=True) ) == {'commutative': True} assert assumptions(Symbol('x'), ['integer']) == {} assert assumptions(Symbol('x'), ['commutative'] ) == {'commutative': True} assert assumptions(Symbol('x')) == {'commutative': True} assert assumptions(1)['positive'] assert assumptions(3 + I) == { 'algebraic': True, 'commutative': True, 'complex': True, 'composite': False, 'even': False, 'extended_negative': False, 'extended_nonnegative': False, 'extended_nonpositive': False, 'extended_nonzero': False, 'extended_positive': False, 'extended_real': False, 'finite': True, 'imaginary': False, 'infinite': False, 'integer': False, 'irrational': False, 'negative': False, 'noninteger': False, 'nonnegative': False, 'nonpositive': False, 'nonzero': False, 'odd': False, 'positive': False, 'prime': False, 'rational': False, 'real': False, 'transcendental': False, 'zero': False} def test_check_assumptions(): assert check_assumptions(1, 0) is False x = Symbol('x', positive=True) assert check_assumptions(1, x) is True assert check_assumptions(1, 1) is True assert check_assumptions(-1, 1) is False i = Symbol('i', integer=True) # don't know if i is positive (or prime, etc...) assert check_assumptions(i, 1) is None assert check_assumptions(Dummy(integer=None), integer=True) is None assert check_assumptions(Dummy(integer=None), integer=False) is None assert check_assumptions(Dummy(integer=False), integer=True) is False assert check_assumptions(Dummy(integer=True), integer=False) is False # no T/F assumptions to check assert check_assumptions(Dummy(integer=False), integer=None) is True raises(ValueError, lambda: check_assumptions(2*x, x, positive=True)) def test_failing_assumptions(): x = Symbol('x', real=True, positive=True) y = Symbol('y') assert failing_assumptions(6*x + y, **x.assumptions0) == \ {'real': None, 'imaginary': None, 'complex': None, 'hermitian': None, 'positive': None, 'nonpositive': None, 'nonnegative': None, 'nonzero': None, 'negative': None, 'zero': None, 'extended_real': None, 'finite': None, 'infinite': None, 'extended_negative': None, 'extended_nonnegative': None, 'extended_nonpositive': None, 'extended_nonzero': None, 'extended_positive': None } def test_common_assumptions(): assert common_assumptions([0, 1, 2] ) == {'algebraic': True, 'irrational': False, 'hermitian': True, 'extended_real': True, 'real': True, 'extended_negative': False, 'extended_nonnegative': True, 'integer': True, 'rational': True, 'imaginary': False, 'complex': True, 'commutative': True,'noninteger': False, 'composite': False, 'infinite': False, 'nonnegative': True, 'finite': True, 'transcendental': False,'negative': False} assert common_assumptions([0, 1, 2], 'positive integer'.split() ) == {'integer': True} assert common_assumptions([0, 1, 2], []) == {} assert common_assumptions([], ['integer']) == {} assert common_assumptions([0], ['integer']) == {'integer': True}
4d1e8e77444eb986eff82ff8f56c46b8eb5caa3560bb4008a4fad6854a8afd12
from sympy import (Symbol, exp, Integer, Float, sin, cos, log, Poly, Lambda, Function, I, S, sqrt, srepr, Rational, Tuple, Matrix, Interval, Add, Mul, Pow, Or, true, false, Abs, pi, Range, Xor) from sympy.abc import x, y from sympy.core.sympify import (sympify, _sympify, SympifyError, kernS, CantSympify) from sympy.core.decorators import _sympifyit from sympy.external import import_module from sympy.testing.pytest import raises, XFAIL, skip, warns_deprecated_sympy from sympy.utilities.decorator import conserve_mpmath_dps from sympy.geometry import Point, Line from sympy.functions.combinatorial.factorials import factorial, factorial2 from sympy.abc import _clash, _clash1, _clash2 from sympy.core.compatibility import HAS_GMPY from sympy.sets import FiniteSet, EmptySet from sympy.tensor.array.dense_ndim_array import ImmutableDenseNDimArray import mpmath from collections import defaultdict, OrderedDict from mpmath.rational import mpq numpy = import_module('numpy') def test_issue_3538(): v = sympify("exp(x)") assert v == exp(x) assert type(v) == type(exp(x)) assert str(type(v)) == str(type(exp(x))) def test_sympify1(): assert sympify("x") == Symbol("x") assert sympify(" x") == Symbol("x") assert sympify(" x ") == Symbol("x") # issue 4877 n1 = S.Half assert sympify('--.5') == n1 assert sympify('-1/2') == -n1 assert sympify('-+--.5') == -n1 assert sympify('-.[3]') == Rational(-1, 3) assert sympify('.[3]') == Rational(1, 3) assert sympify('+.[3]') == Rational(1, 3) assert sympify('+0.[3]*10**-2') == Rational(1, 300) assert sympify('.[052631578947368421]') == Rational(1, 19) assert sympify('.0[526315789473684210]') == Rational(1, 19) assert sympify('.034[56]') == Rational(1711, 49500) # options to make reals into rationals assert sympify('1.22[345]', rational=True) == \ 1 + Rational(22, 100) + Rational(345, 99900) assert sympify('2/2.6', rational=True) == Rational(10, 13) assert sympify('2.6/2', rational=True) == Rational(13, 10) assert sympify('2.6e2/17', rational=True) == Rational(260, 17) assert sympify('2.6e+2/17', rational=True) == Rational(260, 17) assert sympify('2.6e-2/17', rational=True) == Rational(26, 17000) assert sympify('2.1+3/4', rational=True) == \ Rational(21, 10) + Rational(3, 4) assert sympify('2.234456', rational=True) == Rational(279307, 125000) assert sympify('2.234456e23', rational=True) == 223445600000000000000000 assert sympify('2.234456e-23', rational=True) == \ Rational(279307, 12500000000000000000000000000) assert sympify('-2.234456e-23', rational=True) == \ Rational(-279307, 12500000000000000000000000000) assert sympify('12345678901/17', rational=True) == \ Rational(12345678901, 17) assert sympify('1/.3 + x', rational=True) == Rational(10, 3) + x # make sure longs in fractions work assert sympify('222222222222/11111111111') == \ Rational(222222222222, 11111111111) # ... even if they come from repetend notation assert sympify('1/.2[123456789012]') == Rational(333333333333, 70781892967) # ... or from high precision reals assert sympify('.1234567890123456', rational=True) == \ Rational(19290123283179, 156250000000000) def test_sympify_Fraction(): try: import fractions except ImportError: pass else: value = sympify(fractions.Fraction(101, 127)) assert value == Rational(101, 127) and type(value) is Rational def test_sympify_gmpy(): if HAS_GMPY: if HAS_GMPY == 2: import gmpy2 as gmpy elif HAS_GMPY == 1: import gmpy value = sympify(gmpy.mpz(1000001)) assert value == Integer(1000001) and type(value) is Integer value = sympify(gmpy.mpq(101, 127)) assert value == Rational(101, 127) and type(value) is Rational @conserve_mpmath_dps def test_sympify_mpmath(): value = sympify(mpmath.mpf(1.0)) assert value == Float(1.0) and type(value) is Float mpmath.mp.dps = 12 assert sympify( mpmath.pi).epsilon_eq(Float("3.14159265359"), Float("1e-12")) == True assert sympify( mpmath.pi).epsilon_eq(Float("3.14159265359"), Float("1e-13")) == False mpmath.mp.dps = 6 assert sympify( mpmath.pi).epsilon_eq(Float("3.14159"), Float("1e-5")) == True assert sympify( mpmath.pi).epsilon_eq(Float("3.14159"), Float("1e-6")) == False assert sympify(mpmath.mpc(1.0 + 2.0j)) == Float(1.0) + Float(2.0)*I assert sympify(mpq(1, 2)) == S.Half def test_sympify2(): class A: def _sympy_(self): return Symbol("x")**3 a = A() assert _sympify(a) == x**3 assert sympify(a) == x**3 assert a == x**3 def test_sympify3(): assert sympify("x**3") == x**3 assert sympify("x^3") == x**3 assert sympify("1/2") == Integer(1)/2 raises(SympifyError, lambda: _sympify('x**3')) raises(SympifyError, lambda: _sympify('1/2')) def test_sympify_keywords(): raises(SympifyError, lambda: sympify('if')) raises(SympifyError, lambda: sympify('for')) raises(SympifyError, lambda: sympify('while')) raises(SympifyError, lambda: sympify('lambda')) def test_sympify_float(): assert sympify("1e-64") != 0 assert sympify("1e-20000") != 0 def test_sympify_bool(): assert sympify(True) is true assert sympify(False) is false def test_sympyify_iterables(): ans = [Rational(3, 10), Rational(1, 5)] assert sympify(['.3', '.2'], rational=True) == ans assert sympify(dict(x=0, y=1)) == {x: 0, y: 1} assert sympify(['1', '2', ['3', '4']]) == [S(1), S(2), [S(3), S(4)]] @XFAIL def test_issue_16772(): # because there is a converter for tuple, the # args are only sympified without the flags being passed # along; list, on the other hand, is not converted # with a converter so its args are traversed later ans = [Rational(3, 10), Rational(1, 5)] assert sympify(tuple(['.3', '.2']), rational=True) == Tuple(*ans) def test_issue_16859(): class no(float, CantSympify): pass raises(SympifyError, lambda: sympify(no(1.2))) def test_sympify4(): class A: def _sympy_(self): return Symbol("x") a = A() assert _sympify(a)**3 == x**3 assert sympify(a)**3 == x**3 assert a == x def test_sympify_text(): assert sympify('some') == Symbol('some') assert sympify('core') == Symbol('core') assert sympify('True') is True assert sympify('False') is False assert sympify('Poly') == Poly assert sympify('sin') == sin def test_sympify_function(): assert sympify('factor(x**2-1, x)') == -(1 - x)*(x + 1) assert sympify('sin(pi/2)*cos(pi)') == -Integer(1) def test_sympify_poly(): p = Poly(x**2 + x + 1, x) assert _sympify(p) is p assert sympify(p) is p def test_sympify_factorial(): assert sympify('x!') == factorial(x) assert sympify('(x+1)!') == factorial(x + 1) assert sympify('(1 + y*(x + 1))!') == factorial(1 + y*(x + 1)) assert sympify('(1 + y*(x + 1)!)^2') == (1 + y*factorial(x + 1))**2 assert sympify('y*x!') == y*factorial(x) assert sympify('x!!') == factorial2(x) assert sympify('(x+1)!!') == factorial2(x + 1) assert sympify('(1 + y*(x + 1))!!') == factorial2(1 + y*(x + 1)) assert sympify('(1 + y*(x + 1)!!)^2') == (1 + y*factorial2(x + 1))**2 assert sympify('y*x!!') == y*factorial2(x) assert sympify('factorial2(x)!') == factorial(factorial2(x)) raises(SympifyError, lambda: sympify("+!!")) raises(SympifyError, lambda: sympify(")!!")) raises(SympifyError, lambda: sympify("!")) raises(SympifyError, lambda: sympify("(!)")) raises(SympifyError, lambda: sympify("x!!!")) def test_sage(): # how to effectivelly test for the _sage_() method without having SAGE # installed? assert hasattr(x, "_sage_") assert hasattr(Integer(3), "_sage_") assert hasattr(sin(x), "_sage_") assert hasattr(cos(x), "_sage_") assert hasattr(x**2, "_sage_") assert hasattr(x + y, "_sage_") assert hasattr(exp(x), "_sage_") assert hasattr(log(x), "_sage_") def test_issue_3595(): assert sympify("a_") == Symbol("a_") assert sympify("_a") == Symbol("_a") def test_lambda(): x = Symbol('x') assert sympify('lambda: 1') == Lambda((), 1) assert sympify('lambda x: x') == Lambda(x, x) assert sympify('lambda x: 2*x') == Lambda(x, 2*x) assert sympify('lambda x, y: 2*x+y') == Lambda((x, y), 2*x + y) def test_lambda_raises(): raises(SympifyError, lambda: sympify("lambda *args: args")) # args argument error raises(SympifyError, lambda: sympify("lambda **kwargs: kwargs[0]")) # kwargs argument error raises(SympifyError, lambda: sympify("lambda x = 1: x")) # Keyword argument error with raises(SympifyError): _sympify('lambda: 1') def test_sympify_raises(): raises(SympifyError, lambda: sympify("fx)")) class A: def __str__(self): return 'x' with warns_deprecated_sympy(): assert sympify(A()) == Symbol('x') def test__sympify(): x = Symbol('x') f = Function('f') # positive _sympify assert _sympify(x) is x assert _sympify(1) == Integer(1) assert _sympify(0.5) == Float("0.5") assert _sympify(1 + 1j) == 1.0 + I*1.0 # Function f is not Basic and can't sympify to Basic. We allow it to pass # with sympify but not with _sympify. # https://github.com/sympy/sympy/issues/20124 assert sympify(f) is f raises(SympifyError, lambda: _sympify(f)) class A: def _sympy_(self): return Integer(5) a = A() assert _sympify(a) == Integer(5) # negative _sympify raises(SympifyError, lambda: _sympify('1')) raises(SympifyError, lambda: _sympify([1, 2, 3])) def test_sympifyit(): x = Symbol('x') y = Symbol('y') @_sympifyit('b', NotImplemented) def add(a, b): return a + b assert add(x, 1) == x + 1 assert add(x, 0.5) == x + Float('0.5') assert add(x, y) == x + y assert add(x, '1') == NotImplemented @_sympifyit('b') def add_raises(a, b): return a + b assert add_raises(x, 1) == x + 1 assert add_raises(x, 0.5) == x + Float('0.5') assert add_raises(x, y) == x + y raises(SympifyError, lambda: add_raises(x, '1')) def test_int_float(): class F1_1: def __float__(self): return 1.1 class F1_1b: """ This class is still a float, even though it also implements __int__(). """ def __float__(self): return 1.1 def __int__(self): return 1 class F1_1c: """ This class is still a float, because it implements _sympy_() """ def __float__(self): return 1.1 def __int__(self): return 1 def _sympy_(self): return Float(1.1) class I5: def __int__(self): return 5 class I5b: """ This class implements both __int__() and __float__(), so it will be treated as Float in SymPy. One could change this behavior, by using float(a) == int(a), but deciding that integer-valued floats represent exact numbers is arbitrary and often not correct, so we do not do it. If, in the future, we decide to do it anyway, the tests for I5b need to be changed. """ def __float__(self): return 5.0 def __int__(self): return 5 class I5c: """ This class implements both __int__() and __float__(), but also a _sympy_() method, so it will be Integer. """ def __float__(self): return 5.0 def __int__(self): return 5 def _sympy_(self): return Integer(5) i5 = I5() i5b = I5b() i5c = I5c() f1_1 = F1_1() f1_1b = F1_1b() f1_1c = F1_1c() assert sympify(i5) == 5 assert isinstance(sympify(i5), Integer) assert sympify(i5b) == 5 assert isinstance(sympify(i5b), Float) assert sympify(i5c) == 5 assert isinstance(sympify(i5c), Integer) assert abs(sympify(f1_1) - 1.1) < 1e-5 assert abs(sympify(f1_1b) - 1.1) < 1e-5 assert abs(sympify(f1_1c) - 1.1) < 1e-5 assert _sympify(i5) == 5 assert isinstance(_sympify(i5), Integer) assert _sympify(i5b) == 5 assert isinstance(_sympify(i5b), Float) assert _sympify(i5c) == 5 assert isinstance(_sympify(i5c), Integer) assert abs(_sympify(f1_1) - 1.1) < 1e-5 assert abs(_sympify(f1_1b) - 1.1) < 1e-5 assert abs(_sympify(f1_1c) - 1.1) < 1e-5 def test_evaluate_false(): cases = { '2 + 3': Add(2, 3, evaluate=False), '2**2 / 3': Mul(Pow(2, 2, evaluate=False), Pow(3, -1, evaluate=False), evaluate=False), '2 + 3 * 5': Add(2, Mul(3, 5, evaluate=False), evaluate=False), '2 - 3 * 5': Add(2, Mul(-1, Mul(3, 5,evaluate=False), evaluate=False), evaluate=False), '1 / 3': Mul(1, Pow(3, -1, evaluate=False), evaluate=False), 'True | False': Or(True, False, evaluate=False), '1 + 2 + 3 + 5*3 + integrate(x)': Add(1, 2, 3, Mul(5, 3, evaluate=False), x**2/2, evaluate=False), '2 * 4 * 6 + 8': Add(Mul(2, 4, 6, evaluate=False), 8, evaluate=False), '2 - 8 / 4': Add(2, Mul(-1, Mul(8, Pow(4, -1, evaluate=False), evaluate=False), evaluate=False), evaluate=False), '2 - 2**2': Add(2, Mul(-1, Pow(2, 2, evaluate=False), evaluate=False), evaluate=False), } for case, result in cases.items(): assert sympify(case, evaluate=False) == result def test_issue_4133(): a = sympify('Integer(4)') assert a == Integer(4) assert a.is_Integer def test_issue_3982(): a = [3, 2.0] assert sympify(a) == [Integer(3), Float(2.0)] assert sympify(tuple(a)) == Tuple(Integer(3), Float(2.0)) assert sympify(set(a)) == FiniteSet(Integer(3), Float(2.0)) def test_S_sympify(): assert S(1)/2 == sympify(1)/2 assert (-2)**(S(1)/2) == sqrt(2)*I def test_issue_4788(): assert srepr(S(1.0 + 0J)) == srepr(S(1.0)) == srepr(Float(1.0)) def test_issue_4798_None(): assert S(None) is None def test_issue_3218(): assert sympify("x+\ny") == x + y def test_issue_4988_builtins(): C = Symbol('C') vars = {'C': C} exp1 = sympify('C') assert exp1 == C # Make sure it did not get mixed up with sympy.C exp2 = sympify('C', vars) assert exp2 == C # Make sure it did not get mixed up with sympy.C def test_geometry(): p = sympify(Point(0, 1)) assert p == Point(0, 1) and isinstance(p, Point) L = sympify(Line(p, (1, 0))) assert L == Line((0, 1), (1, 0)) and isinstance(L, Line) def test_kernS(): s = '-1 - 2*(-(-x + 1/x)/(x*(x - 1/x)**2) - 1/(x*(x - 1/x)))' # when 1497 is fixed, this no longer should pass: the expression # should be unchanged assert -1 - 2*(-(-x + 1/x)/(x*(x - 1/x)**2) - 1/(x*(x - 1/x))) == -1 # sympification should not allow the constant to enter a Mul # or else the structure can change dramatically ss = kernS(s) assert ss != -1 and ss.simplify() == -1 s = '-1 - 2*(-(-x + 1/x)/(x*(x - 1/x)**2) - 1/(x*(x - 1/x)))'.replace( 'x', '_kern') ss = kernS(s) assert ss != -1 and ss.simplify() == -1 # issue 6687 assert (kernS('Interval(-1,-2 - 4*(-3))') == Interval(-1, Add(-2, Mul(12, 1, evaluate=False), evaluate=False))) assert kernS('_kern') == Symbol('_kern') assert kernS('E**-(x)') == exp(-x) e = 2*(x + y)*y assert kernS(['2*(x + y)*y', ('2*(x + y)*y',)]) == [e, (e,)] assert kernS('-(2*sin(x)**2 + 2*sin(x)*cos(x))*y/2') == \ -y*(2*sin(x)**2 + 2*sin(x)*cos(x))/2 # issue 15132 assert kernS('(1 - x)/(1 - x*(1-y))') == kernS('(1-x)/(1-(1-y)*x)') assert kernS('(1-2**-(4+1)*(1-y)*x)') == (1 - x*(1 - y)/32) assert kernS('(1-2**(4+1)*(1-y)*x)') == (1 - 32*x*(1 - y)) assert kernS('(1-2.*(1-y)*x)') == 1 - 2.*x*(1 - y) one = kernS('x - (x - 1)') assert one != 1 and one.expand() == 1 assert kernS("(2*x)/(x-1)") == 2*x/(x-1) def test_issue_6540_6552(): assert S('[[1/3,2], (2/5,)]') == [[Rational(1, 3), 2], (Rational(2, 5),)] assert S('[[2/6,2], (2/4,)]') == [[Rational(1, 3), 2], (S.Half,)] assert S('[[[2*(1)]]]') == [[[2]]] assert S('Matrix([2*(1)])') == Matrix([2]) def test_issue_6046(): assert str(S("Q & C", locals=_clash1)) == 'C & Q' assert str(S('pi(x)', locals=_clash2)) == 'pi(x)' locals = {} exec("from sympy.abc import Q, C", locals) assert str(S('C&Q', locals)) == 'C & Q' # clash can act as Symbol or Function assert str(S('pi(C, Q)', locals=_clash)) == 'pi(C, Q)' assert len(S('pi + x', locals=_clash2).free_symbols) == 2 # but not both raises(TypeError, lambda: S('pi + pi(x)', locals=_clash2)) assert all(set(i.values()) == {None} for i in ( _clash, _clash1, _clash2)) def test_issue_8821_highprec_from_str(): s = str(pi.evalf(128)) p = sympify(s) assert Abs(sin(p)) < 1e-127 def test_issue_10295(): if not numpy: skip("numpy not installed.") A = numpy.array([[1, 3, -1], [0, 1, 7]]) sA = S(A) assert sA.shape == (2, 3) for (ri, ci), val in numpy.ndenumerate(A): assert sA[ri, ci] == val B = numpy.array([-7, x, 3*y**2]) sB = S(B) assert sB.shape == (3,) assert B[0] == sB[0] == -7 assert B[1] == sB[1] == x assert B[2] == sB[2] == 3*y**2 C = numpy.arange(0, 24) C.resize(2,3,4) sC = S(C) assert sC[0, 0, 0].is_integer assert sC[0, 0, 0] == 0 a1 = numpy.array([1, 2, 3]) a2 = numpy.array([i for i in range(24)]) a2.resize(2, 4, 3) assert sympify(a1) == ImmutableDenseNDimArray([1, 2, 3]) assert sympify(a2) == ImmutableDenseNDimArray([i for i in range(24)], (2, 4, 3)) def test_Range(): # Only works in Python 3 where range returns a range type assert sympify(range(10)) == Range(10) assert _sympify(range(10)) == Range(10) def test_sympify_set(): n = Symbol('n') assert sympify({n}) == FiniteSet(n) assert sympify(set()) == EmptySet def test_sympify_numpy(): if not numpy: skip('numpy not installed. Abort numpy tests.') np = numpy def equal(x, y): return x == y and type(x) == type(y) assert sympify(np.bool_(1)) is S(True) try: assert equal( sympify(np.int_(1234567891234567891)), S(1234567891234567891)) assert equal( sympify(np.intp(1234567891234567891)), S(1234567891234567891)) except OverflowError: # May fail on 32-bit systems: Python int too large to convert to C long pass assert equal(sympify(np.intc(1234567891)), S(1234567891)) assert equal(sympify(np.int8(-123)), S(-123)) assert equal(sympify(np.int16(-12345)), S(-12345)) assert equal(sympify(np.int32(-1234567891)), S(-1234567891)) assert equal( sympify(np.int64(-1234567891234567891)), S(-1234567891234567891)) assert equal(sympify(np.uint8(123)), S(123)) assert equal(sympify(np.uint16(12345)), S(12345)) assert equal(sympify(np.uint32(1234567891)), S(1234567891)) assert equal( sympify(np.uint64(1234567891234567891)), S(1234567891234567891)) assert equal(sympify(np.float32(1.123456)), Float(1.123456, precision=24)) assert equal(sympify(np.float64(1.1234567891234)), Float(1.1234567891234, precision=53)) assert equal(sympify(np.longdouble(1.123456789)), Float(1.123456789, precision=80)) assert equal(sympify(np.complex64(1 + 2j)), S(1.0 + 2.0*I)) assert equal(sympify(np.complex128(1 + 2j)), S(1.0 + 2.0*I)) assert equal(sympify(np.longcomplex(1 + 2j)), S(1.0 + 2.0*I)) #float96 does not exist on all platforms if hasattr(np, 'float96'): assert equal(sympify(np.float96(1.123456789)), Float(1.123456789, precision=80)) #float128 does not exist on all platforms if hasattr(np, 'float128'): assert equal(sympify(np.float128(1.123456789123)), Float(1.123456789123, precision=80)) @XFAIL def test_sympify_rational_numbers_set(): ans = [Rational(3, 10), Rational(1, 5)] assert sympify({'.3', '.2'}, rational=True) == FiniteSet(*ans) def test_issue_13924(): if not numpy: skip("numpy not installed.") a = sympify(numpy.array([1])) assert isinstance(a, ImmutableDenseNDimArray) assert a[0] == 1 def test_numpy_sympify_args(): # Issue 15098. Make sure sympify args work with numpy types (like numpy.str_) if not numpy: skip("numpy not installed.") a = sympify(numpy.str_('a')) assert type(a) is Symbol assert a == Symbol('a') class CustomSymbol(Symbol): pass a = sympify(numpy.str_('a'), {"Symbol": CustomSymbol}) assert isinstance(a, CustomSymbol) a = sympify(numpy.str_('x^y')) assert a == x**y a = sympify(numpy.str_('x^y'), convert_xor=False) assert a == Xor(x, y) raises(SympifyError, lambda: sympify(numpy.str_('x'), strict=True)) a = sympify(numpy.str_('1.1')) assert isinstance(a, Float) assert a == 1.1 a = sympify(numpy.str_('1.1'), rational=True) assert isinstance(a, Rational) assert a == Rational(11, 10) a = sympify(numpy.str_('x + x')) assert isinstance(a, Mul) assert a == 2*x a = sympify(numpy.str_('x + x'), evaluate=False) assert isinstance(a, Add) assert a == Add(x, x, evaluate=False) def test_issue_5939(): a = Symbol('a') b = Symbol('b') assert sympify('''a+\nb''') == a + b def test_issue_16759(): d = sympify({.5: 1}) assert S.Half not in d assert Float(.5) in d assert d[.5] is S.One d = sympify(OrderedDict({.5: 1})) assert S.Half not in d assert Float(.5) in d assert d[.5] is S.One d = sympify(defaultdict(int, {.5: 1})) assert S.Half not in d assert Float(.5) in d assert d[.5] is S.One def test_issue_17811(): a = Function('a') assert sympify('a(x)*5', evaluate=False) == Mul(a(x), 5, evaluate=False) def test_issue_14706(): if not numpy: skip("numpy not installed.") z1 = numpy.zeros((1, 1), dtype=numpy.float) z2 = numpy.zeros((2, 2), dtype=numpy.float) z3 = numpy.zeros((), dtype=numpy.float) y1 = numpy.ones((1, 1), dtype=numpy.float) y2 = numpy.ones((2, 2), dtype=numpy.float) y3 = numpy.ones((), dtype=numpy.float) assert numpy.all(x + z1 == numpy.full((1, 1), x)) assert numpy.all(x + z2 == numpy.full((2, 2), x)) assert numpy.all(z1 + x == numpy.full((1, 1), x)) assert numpy.all(z2 + x == numpy.full((2, 2), x)) for z in [z3, numpy.int(0), numpy.float(0), numpy.complex(0)]: assert x + z == x assert z + x == x assert isinstance(x + z, Symbol) assert isinstance(z + x, Symbol) # If these tests fail, then it means that numpy has finally # fixed the issue of scalar conversion for rank>0 arrays # which is mentioned in numpy/numpy#10404. In that case, # some changes have to be made in sympify.py. # Note: For future reference, for anyone who takes up this # issue when numpy has finally fixed their side of the problem, # the changes for this temporary fix were introduced in PR 18651 assert numpy.all(x + y1 == numpy.full((1, 1), x + 1.0)) assert numpy.all(x + y2 == numpy.full((2, 2), x + 1.0)) assert numpy.all(y1 + x == numpy.full((1, 1), x + 1.0)) assert numpy.all(y2 + x == numpy.full((2, 2), x + 1.0)) for y_ in [y3, numpy.int(1), numpy.float(1), numpy.complex(1)]: assert x + y_ == y_ + x assert isinstance(x + y_, Add) assert isinstance(y_ + x, Add) assert x + numpy.array(x) == 2 * x assert x + numpy.array([x]) == numpy.array([2*x], dtype=object) assert sympify(numpy.array([1])) == ImmutableDenseNDimArray([1], 1) assert sympify(numpy.array([[[1]]])) == ImmutableDenseNDimArray([1], (1, 1, 1)) assert sympify(z1) == ImmutableDenseNDimArray([0], (1, 1)) assert sympify(z2) == ImmutableDenseNDimArray([0, 0, 0, 0], (2, 2)) assert sympify(z3) == ImmutableDenseNDimArray([0], ()) assert sympify(z3, strict=True) == 0.0 raises(SympifyError, lambda: sympify(numpy.array([1]), strict=True)) raises(SympifyError, lambda: sympify(z1, strict=True)) raises(SympifyError, lambda: sympify(z2, strict=True)) def test_issue_21536(): #test to check evaluate=False in case of iterable input u = sympify("x+3*x+2", evaluate=False) v = sympify("2*x+4*x+2+4", evaluate=False) assert u.is_Add and set(u.args) == {x, 3*x, 2} assert v.is_Add and set(v.args) == {2*x, 4*x, 2, 4} assert sympify(["x+3*x+2", "2*x+4*x+2+4"], evaluate=False) == [u, v] #test to check evaluate=True in case of iterable input u = sympify("x+3*x+2", evaluate=True) v = sympify("2*x+4*x+2+4", evaluate=True) assert u.is_Add and set(u.args) == {4*x, 2} assert v.is_Add and set(v.args) == {6*x, 6} assert sympify(["x+3*x+2", "2*x+4*x+2+4"], evaluate=True) == [u, v] #test to check evaluate with no input in case of iterable input u = sympify("x+3*x+2") v = sympify("2*x+4*x+2+4") assert u.is_Add and set(u.args) == {4*x, 2} assert v.is_Add and set(v.args) == {6*x, 6} assert sympify(["x+3*x+2", "2*x+4*x+2+4"]) == [u, v]
5d2a714eda63b96b401919e42d35d870cb4b11dd741f75697060b157df6a282f
from sympy import (Basic, Symbol, sin, cos, atan, exp, sqrt, Rational, Float, re, pi, sympify, Add, Mul, Pow, Mod, I, log, S, Max, symbols, oo, zoo, Integer, sign, im, nan, Dummy, factorial, comp, floor, Poly, FiniteSet ) from sympy.core.parameters import distribute from sympy.core.expr import unchanged from sympy.utilities.iterables import cartes from sympy.testing.pytest import XFAIL, raises, warns_deprecated_sympy from sympy.testing.randtest import verify_numerically from sympy.functions.elementary.trigonometric import asin a, c, x, y, z = symbols('a,c,x,y,z') b = Symbol("b", positive=True) def same_and_same_prec(a, b): # stricter matching for Floats return a == b and a._prec == b._prec def test_bug1(): assert re(x) != x x.series(x, 0, 1) assert re(x) != x def test_Symbol(): e = a*b assert e == a*b assert a*b*b == a*b**2 assert a*b*b + c == c + a*b**2 assert a*b*b - c == -c + a*b**2 x = Symbol('x', complex=True, real=False) assert x.is_imaginary is None # could be I or 1 + I x = Symbol('x', complex=True, imaginary=False) assert x.is_real is None # could be 1 or 1 + I x = Symbol('x', real=True) assert x.is_complex x = Symbol('x', imaginary=True) assert x.is_complex x = Symbol('x', real=False, imaginary=False) assert x.is_complex is None # might be a non-number def test_arit0(): p = Rational(5) e = a*b assert e == a*b e = a*b + b*a assert e == 2*a*b e = a*b + b*a + a*b + p*b*a assert e == 8*a*b e = a*b + b*a + a*b + p*b*a + a assert e == a + 8*a*b e = a + a assert e == 2*a e = a + b + a assert e == b + 2*a e = a + b*b + a + b*b assert e == 2*a + 2*b**2 e = a + Rational(2) + b*b + a + b*b + p assert e == 7 + 2*a + 2*b**2 e = (a + b*b + a + b*b)*p assert e == 5*(2*a + 2*b**2) e = (a*b*c + c*b*a + b*a*c)*p assert e == 15*a*b*c e = (a*b*c + c*b*a + b*a*c)*p - Rational(15)*a*b*c assert e == Rational(0) e = Rational(50)*(a - a) assert e == Rational(0) e = b*a - b - a*b + b assert e == Rational(0) e = a*b + c**p assert e == a*b + c**5 e = a/b assert e == a*b**(-1) e = a*2*2 assert e == 4*a e = 2 + a*2/2 assert e == 2 + a e = 2 - a - 2 assert e == -a e = 2*a*2 assert e == 4*a e = 2/a/2 assert e == a**(-1) e = 2**a**2 assert e == 2**(a**2) e = -(1 + a) assert e == -1 - a e = S.Half*(1 + a) assert e == S.Half + a/2 def test_div(): e = a/b assert e == a*b**(-1) e = a/b + c/2 assert e == a*b**(-1) + Rational(1)/2*c e = (1 - b)/(b - 1) assert e == (1 + -b)*((-1) + b)**(-1) def test_pow(): n1 = Rational(1) n2 = Rational(2) n5 = Rational(5) e = a*a assert e == a**2 e = a*a*a assert e == a**3 e = a*a*a*a**Rational(6) assert e == a**9 e = a*a*a*a**Rational(6) - a**Rational(9) assert e == Rational(0) e = a**(b - b) assert e == Rational(1) e = (a + Rational(1) - a)**b assert e == Rational(1) e = (a + b + c)**n2 assert e == (a + b + c)**2 assert e.expand() == 2*b*c + 2*a*c + 2*a*b + a**2 + c**2 + b**2 e = (a + b)**n2 assert e == (a + b)**2 assert e.expand() == 2*a*b + a**2 + b**2 e = (a + b)**(n1/n2) assert e == sqrt(a + b) assert e.expand() == sqrt(a + b) n = n5**(n1/n2) assert n == sqrt(5) e = n*a*b - n*b*a assert e == Rational(0) e = n*a*b + n*b*a assert e == 2*a*b*sqrt(5) assert e.diff(a) == 2*b*sqrt(5) assert e.diff(a) == 2*b*sqrt(5) e = a/b**2 assert e == a*b**(-2) assert sqrt(2*(1 + sqrt(2))) == (2*(1 + 2**S.Half))**S.Half x = Symbol('x') y = Symbol('y') assert ((x*y)**3).expand() == y**3 * x**3 assert ((x*y)**-3).expand() == y**-3 * x**-3 assert (x**5*(3*x)**(3)).expand() == 27 * x**8 assert (x**5*(-3*x)**(3)).expand() == -27 * x**8 assert (x**5*(3*x)**(-3)).expand() == x**2 * Rational(1, 27) assert (x**5*(-3*x)**(-3)).expand() == x**2 * Rational(-1, 27) # expand_power_exp assert (x**(y**(x + exp(x + y)) + z)).expand(deep=False) == \ x**z*x**(y**(x + exp(x + y))) assert (x**(y**(x + exp(x + y)) + z)).expand() == \ x**z*x**(y**x*y**(exp(x)*exp(y))) n = Symbol('n', even=False) k = Symbol('k', even=True) o = Symbol('o', odd=True) assert unchanged(Pow, -1, x) assert unchanged(Pow, -1, n) assert (-2)**k == 2**k assert (-1)**k == 1 assert (-1)**o == -1 def test_pow2(): # x**(2*y) is always (x**y)**2 but is only (x**2)**y if # x.is_positive or y.is_integer # let x = 1 to see why the following are not true. assert (-x)**Rational(2, 3) != x**Rational(2, 3) assert (-x)**Rational(5, 7) != -x**Rational(5, 7) assert ((-x)**2)**Rational(1, 3) != ((-x)**Rational(1, 3))**2 assert sqrt(x**2) != x def test_pow3(): assert sqrt(2)**3 == 2 * sqrt(2) assert sqrt(2)**3 == sqrt(8) def test_mod_pow(): for s, t, u, v in [(4, 13, 497, 445), (4, -3, 497, 365), (3.2, 2.1, 1.9, 0.1031015682350942), (S(3)/2, 5, S(5)/6, S(3)/32)]: assert pow(S(s), t, u) == v assert pow(S(s), S(t), u) == v assert pow(S(s), t, S(u)) == v assert pow(S(s), S(t), S(u)) == v assert pow(S(2), S(10000000000), S(3)) == 1 assert pow(x, y, z) == x**y%z raises(TypeError, lambda: pow(S(4), "13", 497)) raises(TypeError, lambda: pow(S(4), 13, "497")) def test_pow_E(): assert 2**(y/log(2)) == S.Exp1**y assert 2**(y/log(2)/3) == S.Exp1**(y/3) assert 3**(1/log(-3)) != S.Exp1 assert (3 + 2*I)**(1/(log(-3 - 2*I) + I*pi)) == S.Exp1 assert (4 + 2*I)**(1/(log(-4 - 2*I) + I*pi)) == S.Exp1 assert (3 + 2*I)**(1/(log(-3 - 2*I, 3)/2 + I*pi/log(3)/2)) == 9 assert (3 + 2*I)**(1/(log(3 + 2*I, 3)/2)) == 9 # every time tests are run they will affirm with a different random # value that this identity holds while 1: b = x._random() r, i = b.as_real_imag() if i: break assert verify_numerically(b**(1/(log(-b) + sign(i)*I*pi).n()), S.Exp1) def test_pow_issue_3516(): assert 4**Rational(1, 4) == sqrt(2) def test_pow_im(): for m in (-2, -1, 2): for d in (3, 4, 5): b = m*I for i in range(1, 4*d + 1): e = Rational(i, d) assert (b**e - b.n()**e.n()).n(2, chop=1e-10) == 0 e = Rational(7, 3) assert (2*x*I)**e == 4*2**Rational(1, 3)*(I*x)**e # same as Wolfram Alpha im = symbols('im', imaginary=True) assert (2*im*I)**e == 4*2**Rational(1, 3)*(I*im)**e args = [I, I, I, I, 2] e = Rational(1, 3) ans = 2**e assert Mul(*args, evaluate=False)**e == ans assert Mul(*args)**e == ans args = [I, I, I, 2] e = Rational(1, 3) ans = 2**e*(-I)**e assert Mul(*args, evaluate=False)**e == ans assert Mul(*args)**e == ans args.append(-3) ans = (6*I)**e assert Mul(*args, evaluate=False)**e == ans assert Mul(*args)**e == ans args.append(-1) ans = (-6*I)**e assert Mul(*args, evaluate=False)**e == ans assert Mul(*args)**e == ans args = [I, I, 2] e = Rational(1, 3) ans = (-2)**e assert Mul(*args, evaluate=False)**e == ans assert Mul(*args)**e == ans args.append(-3) ans = (6)**e assert Mul(*args, evaluate=False)**e == ans assert Mul(*args)**e == ans args.append(-1) ans = (-6)**e assert Mul(*args, evaluate=False)**e == ans assert Mul(*args)**e == ans assert Mul(Pow(-1, Rational(3, 2), evaluate=False), I, I) == I assert Mul(I*Pow(I, S.Half, evaluate=False)) == sqrt(I)*I def test_real_mul(): assert Float(0) * pi * x == 0 assert set((Float(1) * pi * x).args) == {Float(1), pi, x} def test_ncmul(): A = Symbol("A", commutative=False) B = Symbol("B", commutative=False) C = Symbol("C", commutative=False) assert A*B != B*A assert A*B*C != C*B*A assert A*b*B*3*C == 3*b*A*B*C assert A*b*B*3*C != 3*b*B*A*C assert A*b*B*3*C == 3*A*B*C*b assert A + B == B + A assert (A + B)*C != C*(A + B) assert C*(A + B)*C != C*C*(A + B) assert A*A == A**2 assert (A + B)*(A + B) == (A + B)**2 assert A**-1 * A == 1 assert A/A == 1 assert A/(A**2) == 1/A assert A/(1 + A) == A/(1 + A) assert set((A + B + 2*(A + B)).args) == \ {A, B, 2*(A + B)} def test_mul_add_identity(): m = Mul(1, 2) assert isinstance(m, Rational) and m.p == 2 and m.q == 1 m = Mul(1, 2, evaluate=False) assert isinstance(m, Mul) and m.args == (1, 2) m = Mul(0, 1) assert m is S.Zero m = Mul(0, 1, evaluate=False) assert isinstance(m, Mul) and m.args == (0, 1) m = Add(0, 1) assert m is S.One m = Add(0, 1, evaluate=False) assert isinstance(m, Add) and m.args == (0, 1) def test_ncpow(): x = Symbol('x', commutative=False) y = Symbol('y', commutative=False) z = Symbol('z', commutative=False) a = Symbol('a') b = Symbol('b') c = Symbol('c') assert (x**2)*(y**2) != (y**2)*(x**2) assert (x**-2)*y != y*(x**2) assert 2**x*2**y != 2**(x + y) assert 2**x*2**y*2**z != 2**(x + y + z) assert 2**x*2**(2*x) == 2**(3*x) assert 2**x*2**(2*x)*2**x == 2**(4*x) assert exp(x)*exp(y) != exp(y)*exp(x) assert exp(x)*exp(y)*exp(z) != exp(y)*exp(x)*exp(z) assert exp(x)*exp(y)*exp(z) != exp(x + y + z) assert x**a*x**b != x**(a + b) assert x**a*x**b*x**c != x**(a + b + c) assert x**3*x**4 == x**7 assert x**3*x**4*x**2 == x**9 assert x**a*x**(4*a) == x**(5*a) assert x**a*x**(4*a)*x**a == x**(6*a) def test_powerbug(): x = Symbol("x") assert x**1 != (-x)**1 assert x**2 == (-x)**2 assert x**3 != (-x)**3 assert x**4 == (-x)**4 assert x**5 != (-x)**5 assert x**6 == (-x)**6 assert x**128 == (-x)**128 assert x**129 != (-x)**129 assert (2*x)**2 == (-2*x)**2 def test_Mul_doesnt_expand_exp(): x = Symbol('x') y = Symbol('y') assert unchanged(Mul, exp(x), exp(y)) assert unchanged(Mul, 2**x, 2**y) assert x**2*x**3 == x**5 assert 2**x*3**x == 6**x assert x**(y)*x**(2*y) == x**(3*y) assert sqrt(2)*sqrt(2) == 2 assert 2**x*2**(2*x) == 2**(3*x) assert sqrt(2)*2**Rational(1, 4)*5**Rational(3, 4) == 10**Rational(3, 4) assert (x**(-log(5)/log(3))*x)/(x*x**( - log(5)/log(3))) == sympify(1) def test_Mul_is_integer(): k = Symbol('k', integer=True) n = Symbol('n', integer=True) nr = Symbol('nr', rational=False) nz = Symbol('nz', integer=True, zero=False) e = Symbol('e', even=True) o = Symbol('o', odd=True) i2 = Symbol('2', prime=True, even=True) assert (k/3).is_integer is None assert (nz/3).is_integer is None assert (nr/3).is_integer is False assert (x*k*n).is_integer is None assert (e/2).is_integer is True assert (e**2/2).is_integer is True assert (2/k).is_integer is None assert (2/k**2).is_integer is None assert ((-1)**k*n).is_integer is True assert (3*k*e/2).is_integer is True assert (2*k*e/3).is_integer is None assert (e/o).is_integer is None assert (o/e).is_integer is False assert (o/i2).is_integer is False assert Mul(k, 1/k, evaluate=False).is_integer is None assert Mul(2., S.Half, evaluate=False).is_integer is None assert (2*sqrt(k)).is_integer is None assert (2*k**n).is_integer is None s = 2**2**2**Pow(2, 1000, evaluate=False) m = Mul(s, s, evaluate=False) assert m.is_integer # broken in 1.6 and before, see #20161 xq = Symbol('xq', rational=True) yq = Symbol('yq', rational=True) assert (xq*yq).is_integer is None e_20161 = Mul(-1,Mul(1,Pow(2,-1,evaluate=False),evaluate=False),evaluate=False) assert e_20161.is_integer is not True # expand(e_20161) -> -1/2, but no need to see that in the assumption without evaluation def test_Add_Mul_is_integer(): x = Symbol('x') k = Symbol('k', integer=True) n = Symbol('n', integer=True) nk = Symbol('nk', integer=False) nr = Symbol('nr', rational=False) nz = Symbol('nz', integer=True, zero=False) assert (-nk).is_integer is None assert (-nr).is_integer is False assert (2*k).is_integer is True assert (-k).is_integer is True assert (k + nk).is_integer is False assert (k + n).is_integer is True assert (k + x).is_integer is None assert (k + n*x).is_integer is None assert (k + n/3).is_integer is None assert (k + nz/3).is_integer is None assert (k + nr/3).is_integer is False assert ((1 + sqrt(3))*(-sqrt(3) + 1)).is_integer is not False assert (1 + (1 + sqrt(3))*(-sqrt(3) + 1)).is_integer is not False def test_Add_Mul_is_finite(): x = Symbol('x', extended_real=True, finite=False) assert sin(x).is_finite is True assert (x*sin(x)).is_finite is None assert (x*atan(x)).is_finite is False assert (1024*sin(x)).is_finite is True assert (sin(x)*exp(x)).is_finite is None assert (sin(x)*cos(x)).is_finite is True assert (x*sin(x)*exp(x)).is_finite is None assert (sin(x) - 67).is_finite is True assert (sin(x) + exp(x)).is_finite is not True assert (1 + x).is_finite is False assert (1 + x**2 + (1 + x)*(1 - x)).is_finite is None assert (sqrt(2)*(1 + x)).is_finite is False assert (sqrt(2)*(1 + x)*(1 - x)).is_finite is False def test_Mul_is_even_odd(): x = Symbol('x', integer=True) y = Symbol('y', integer=True) k = Symbol('k', odd=True) n = Symbol('n', odd=True) m = Symbol('m', even=True) assert (2*x).is_even is True assert (2*x).is_odd is False assert (3*x).is_even is None assert (3*x).is_odd is None assert (k/3).is_integer is None assert (k/3).is_even is None assert (k/3).is_odd is None assert (2*n).is_even is True assert (2*n).is_odd is False assert (2*m).is_even is True assert (2*m).is_odd is False assert (-n).is_even is False assert (-n).is_odd is True assert (k*n).is_even is False assert (k*n).is_odd is True assert (k*m).is_even is True assert (k*m).is_odd is False assert (k*n*m).is_even is True assert (k*n*m).is_odd is False assert (k*m*x).is_even is True assert (k*m*x).is_odd is False # issue 6791: assert (x/2).is_integer is None assert (k/2).is_integer is False assert (m/2).is_integer is True assert (x*y).is_even is None assert (x*x).is_even is None assert (x*(x + k)).is_even is True assert (x*(x + m)).is_even is None assert (x*y).is_odd is None assert (x*x).is_odd is None assert (x*(x + k)).is_odd is False assert (x*(x + m)).is_odd is None @XFAIL def test_evenness_in_ternary_integer_product_with_odd(): # Tests that oddness inference is independent of term ordering. # Term ordering at the point of testing depends on SymPy's symbol order, so # we try to force a different order by modifying symbol names. x = Symbol('x', integer=True) y = Symbol('y', integer=True) k = Symbol('k', odd=True) assert (x*y*(y + k)).is_even is True assert (y*x*(x + k)).is_even is True def test_evenness_in_ternary_integer_product_with_even(): x = Symbol('x', integer=True) y = Symbol('y', integer=True) m = Symbol('m', even=True) assert (x*y*(y + m)).is_even is None @XFAIL def test_oddness_in_ternary_integer_product_with_odd(): # Tests that oddness inference is independent of term ordering. # Term ordering at the point of testing depends on SymPy's symbol order, so # we try to force a different order by modifying symbol names. x = Symbol('x', integer=True) y = Symbol('y', integer=True) k = Symbol('k', odd=True) assert (x*y*(y + k)).is_odd is False assert (y*x*(x + k)).is_odd is False def test_oddness_in_ternary_integer_product_with_even(): x = Symbol('x', integer=True) y = Symbol('y', integer=True) m = Symbol('m', even=True) assert (x*y*(y + m)).is_odd is None def test_Mul_is_rational(): x = Symbol('x') n = Symbol('n', integer=True) m = Symbol('m', integer=True, nonzero=True) assert (n/m).is_rational is True assert (x/pi).is_rational is None assert (x/n).is_rational is None assert (m/pi).is_rational is False r = Symbol('r', rational=True) assert (pi*r).is_rational is None # issue 8008 z = Symbol('z', zero=True) i = Symbol('i', imaginary=True) assert (z*i).is_rational is True bi = Symbol('i', imaginary=True, finite=True) assert (z*bi).is_zero is True def test_Add_is_rational(): x = Symbol('x') n = Symbol('n', rational=True) m = Symbol('m', rational=True) assert (n + m).is_rational is True assert (x + pi).is_rational is None assert (x + n).is_rational is None assert (n + pi).is_rational is False def test_Add_is_even_odd(): x = Symbol('x', integer=True) k = Symbol('k', odd=True) n = Symbol('n', odd=True) m = Symbol('m', even=True) assert (k + 7).is_even is True assert (k + 7).is_odd is False assert (-k + 7).is_even is True assert (-k + 7).is_odd is False assert (k - 12).is_even is False assert (k - 12).is_odd is True assert (-k - 12).is_even is False assert (-k - 12).is_odd is True assert (k + n).is_even is True assert (k + n).is_odd is False assert (k + m).is_even is False assert (k + m).is_odd is True assert (k + n + m).is_even is True assert (k + n + m).is_odd is False assert (k + n + x + m).is_even is None assert (k + n + x + m).is_odd is None def test_Mul_is_negative_positive(): x = Symbol('x', real=True) y = Symbol('y', extended_real=False, complex=True) z = Symbol('z', zero=True) e = 2*z assert e.is_Mul and e.is_positive is False and e.is_negative is False neg = Symbol('neg', negative=True) pos = Symbol('pos', positive=True) nneg = Symbol('nneg', nonnegative=True) npos = Symbol('npos', nonpositive=True) assert neg.is_negative is True assert (-neg).is_negative is False assert (2*neg).is_negative is True assert (2*pos)._eval_is_extended_negative() is False assert (2*pos).is_negative is False assert pos.is_negative is False assert (-pos).is_negative is True assert (2*pos).is_negative is False assert (pos*neg).is_negative is True assert (2*pos*neg).is_negative is True assert (-pos*neg).is_negative is False assert (pos*neg*y).is_negative is False # y.is_real=F; !real -> !neg assert nneg.is_negative is False assert (-nneg).is_negative is None assert (2*nneg).is_negative is False assert npos.is_negative is None assert (-npos).is_negative is False assert (2*npos).is_negative is None assert (nneg*npos).is_negative is None assert (neg*nneg).is_negative is None assert (neg*npos).is_negative is False assert (pos*nneg).is_negative is False assert (pos*npos).is_negative is None assert (npos*neg*nneg).is_negative is False assert (npos*pos*nneg).is_negative is None assert (-npos*neg*nneg).is_negative is None assert (-npos*pos*nneg).is_negative is False assert (17*npos*neg*nneg).is_negative is False assert (17*npos*pos*nneg).is_negative is None assert (neg*npos*pos*nneg).is_negative is False assert (x*neg).is_negative is None assert (nneg*npos*pos*x*neg).is_negative is None assert neg.is_positive is False assert (-neg).is_positive is True assert (2*neg).is_positive is False assert pos.is_positive is True assert (-pos).is_positive is False assert (2*pos).is_positive is True assert (pos*neg).is_positive is False assert (2*pos*neg).is_positive is False assert (-pos*neg).is_positive is True assert (-pos*neg*y).is_positive is False # y.is_real=F; !real -> !neg assert nneg.is_positive is None assert (-nneg).is_positive is False assert (2*nneg).is_positive is None assert npos.is_positive is False assert (-npos).is_positive is None assert (2*npos).is_positive is False assert (nneg*npos).is_positive is False assert (neg*nneg).is_positive is False assert (neg*npos).is_positive is None assert (pos*nneg).is_positive is None assert (pos*npos).is_positive is False assert (npos*neg*nneg).is_positive is None assert (npos*pos*nneg).is_positive is False assert (-npos*neg*nneg).is_positive is False assert (-npos*pos*nneg).is_positive is None assert (17*npos*neg*nneg).is_positive is None assert (17*npos*pos*nneg).is_positive is False assert (neg*npos*pos*nneg).is_positive is None assert (x*neg).is_positive is None assert (nneg*npos*pos*x*neg).is_positive is None def test_Mul_is_negative_positive_2(): a = Symbol('a', nonnegative=True) b = Symbol('b', nonnegative=True) c = Symbol('c', nonpositive=True) d = Symbol('d', nonpositive=True) assert (a*b).is_nonnegative is True assert (a*b).is_negative is False assert (a*b).is_zero is None assert (a*b).is_positive is None assert (c*d).is_nonnegative is True assert (c*d).is_negative is False assert (c*d).is_zero is None assert (c*d).is_positive is None assert (a*c).is_nonpositive is True assert (a*c).is_positive is False assert (a*c).is_zero is None assert (a*c).is_negative is None def test_Mul_is_nonpositive_nonnegative(): x = Symbol('x', real=True) k = Symbol('k', negative=True) n = Symbol('n', positive=True) u = Symbol('u', nonnegative=True) v = Symbol('v', nonpositive=True) assert k.is_nonpositive is True assert (-k).is_nonpositive is False assert (2*k).is_nonpositive is True assert n.is_nonpositive is False assert (-n).is_nonpositive is True assert (2*n).is_nonpositive is False assert (n*k).is_nonpositive is True assert (2*n*k).is_nonpositive is True assert (-n*k).is_nonpositive is False assert u.is_nonpositive is None assert (-u).is_nonpositive is True assert (2*u).is_nonpositive is None assert v.is_nonpositive is True assert (-v).is_nonpositive is None assert (2*v).is_nonpositive is True assert (u*v).is_nonpositive is True assert (k*u).is_nonpositive is True assert (k*v).is_nonpositive is None assert (n*u).is_nonpositive is None assert (n*v).is_nonpositive is True assert (v*k*u).is_nonpositive is None assert (v*n*u).is_nonpositive is True assert (-v*k*u).is_nonpositive is True assert (-v*n*u).is_nonpositive is None assert (17*v*k*u).is_nonpositive is None assert (17*v*n*u).is_nonpositive is True assert (k*v*n*u).is_nonpositive is None assert (x*k).is_nonpositive is None assert (u*v*n*x*k).is_nonpositive is None assert k.is_nonnegative is False assert (-k).is_nonnegative is True assert (2*k).is_nonnegative is False assert n.is_nonnegative is True assert (-n).is_nonnegative is False assert (2*n).is_nonnegative is True assert (n*k).is_nonnegative is False assert (2*n*k).is_nonnegative is False assert (-n*k).is_nonnegative is True assert u.is_nonnegative is True assert (-u).is_nonnegative is None assert (2*u).is_nonnegative is True assert v.is_nonnegative is None assert (-v).is_nonnegative is True assert (2*v).is_nonnegative is None assert (u*v).is_nonnegative is None assert (k*u).is_nonnegative is None assert (k*v).is_nonnegative is True assert (n*u).is_nonnegative is True assert (n*v).is_nonnegative is None assert (v*k*u).is_nonnegative is True assert (v*n*u).is_nonnegative is None assert (-v*k*u).is_nonnegative is None assert (-v*n*u).is_nonnegative is True assert (17*v*k*u).is_nonnegative is True assert (17*v*n*u).is_nonnegative is None assert (k*v*n*u).is_nonnegative is True assert (x*k).is_nonnegative is None assert (u*v*n*x*k).is_nonnegative is None def test_Add_is_negative_positive(): x = Symbol('x', real=True) k = Symbol('k', negative=True) n = Symbol('n', positive=True) u = Symbol('u', nonnegative=True) v = Symbol('v', nonpositive=True) assert (k - 2).is_negative is True assert (k + 17).is_negative is None assert (-k - 5).is_negative is None assert (-k + 123).is_negative is False assert (k - n).is_negative is True assert (k + n).is_negative is None assert (-k - n).is_negative is None assert (-k + n).is_negative is False assert (k - n - 2).is_negative is True assert (k + n + 17).is_negative is None assert (-k - n - 5).is_negative is None assert (-k + n + 123).is_negative is False assert (-2*k + 123*n + 17).is_negative is False assert (k + u).is_negative is None assert (k + v).is_negative is True assert (n + u).is_negative is False assert (n + v).is_negative is None assert (u - v).is_negative is False assert (u + v).is_negative is None assert (-u - v).is_negative is None assert (-u + v).is_negative is None assert (u - v + n + 2).is_negative is False assert (u + v + n + 2).is_negative is None assert (-u - v + n + 2).is_negative is None assert (-u + v + n + 2).is_negative is None assert (k + x).is_negative is None assert (k + x - n).is_negative is None assert (k - 2).is_positive is False assert (k + 17).is_positive is None assert (-k - 5).is_positive is None assert (-k + 123).is_positive is True assert (k - n).is_positive is False assert (k + n).is_positive is None assert (-k - n).is_positive is None assert (-k + n).is_positive is True assert (k - n - 2).is_positive is False assert (k + n + 17).is_positive is None assert (-k - n - 5).is_positive is None assert (-k + n + 123).is_positive is True assert (-2*k + 123*n + 17).is_positive is True assert (k + u).is_positive is None assert (k + v).is_positive is False assert (n + u).is_positive is True assert (n + v).is_positive is None assert (u - v).is_positive is None assert (u + v).is_positive is None assert (-u - v).is_positive is None assert (-u + v).is_positive is False assert (u - v - n - 2).is_positive is None assert (u + v - n - 2).is_positive is None assert (-u - v - n - 2).is_positive is None assert (-u + v - n - 2).is_positive is False assert (n + x).is_positive is None assert (n + x - k).is_positive is None z = (-3 - sqrt(5) + (-sqrt(10)/2 - sqrt(2)/2)**2) assert z.is_zero z = sqrt(1 + sqrt(3)) + sqrt(3 + 3*sqrt(3)) - sqrt(10 + 6*sqrt(3)) assert z.is_zero def test_Add_is_nonpositive_nonnegative(): x = Symbol('x', real=True) k = Symbol('k', negative=True) n = Symbol('n', positive=True) u = Symbol('u', nonnegative=True) v = Symbol('v', nonpositive=True) assert (u - 2).is_nonpositive is None assert (u + 17).is_nonpositive is False assert (-u - 5).is_nonpositive is True assert (-u + 123).is_nonpositive is None assert (u - v).is_nonpositive is None assert (u + v).is_nonpositive is None assert (-u - v).is_nonpositive is None assert (-u + v).is_nonpositive is True assert (u - v - 2).is_nonpositive is None assert (u + v + 17).is_nonpositive is None assert (-u - v - 5).is_nonpositive is None assert (-u + v - 123).is_nonpositive is True assert (-2*u + 123*v - 17).is_nonpositive is True assert (k + u).is_nonpositive is None assert (k + v).is_nonpositive is True assert (n + u).is_nonpositive is False assert (n + v).is_nonpositive is None assert (k - n).is_nonpositive is True assert (k + n).is_nonpositive is None assert (-k - n).is_nonpositive is None assert (-k + n).is_nonpositive is False assert (k - n + u + 2).is_nonpositive is None assert (k + n + u + 2).is_nonpositive is None assert (-k - n + u + 2).is_nonpositive is None assert (-k + n + u + 2).is_nonpositive is False assert (u + x).is_nonpositive is None assert (v - x - n).is_nonpositive is None assert (u - 2).is_nonnegative is None assert (u + 17).is_nonnegative is True assert (-u - 5).is_nonnegative is False assert (-u + 123).is_nonnegative is None assert (u - v).is_nonnegative is True assert (u + v).is_nonnegative is None assert (-u - v).is_nonnegative is None assert (-u + v).is_nonnegative is None assert (u - v + 2).is_nonnegative is True assert (u + v + 17).is_nonnegative is None assert (-u - v - 5).is_nonnegative is None assert (-u + v - 123).is_nonnegative is False assert (2*u - 123*v + 17).is_nonnegative is True assert (k + u).is_nonnegative is None assert (k + v).is_nonnegative is False assert (n + u).is_nonnegative is True assert (n + v).is_nonnegative is None assert (k - n).is_nonnegative is False assert (k + n).is_nonnegative is None assert (-k - n).is_nonnegative is None assert (-k + n).is_nonnegative is True assert (k - n - u - 2).is_nonnegative is False assert (k + n - u - 2).is_nonnegative is None assert (-k - n - u - 2).is_nonnegative is None assert (-k + n - u - 2).is_nonnegative is None assert (u - x).is_nonnegative is None assert (v + x + n).is_nonnegative is None def test_Pow_is_integer(): x = Symbol('x') k = Symbol('k', integer=True) n = Symbol('n', integer=True, nonnegative=True) m = Symbol('m', integer=True, positive=True) assert (k**2).is_integer is True assert (k**(-2)).is_integer is None assert ((m + 1)**(-2)).is_integer is False assert (m**(-1)).is_integer is None # issue 8580 assert (2**k).is_integer is None assert (2**(-k)).is_integer is None assert (2**n).is_integer is True assert (2**(-n)).is_integer is None assert (2**m).is_integer is True assert (2**(-m)).is_integer is False assert (x**2).is_integer is None assert (2**x).is_integer is None assert (k**n).is_integer is True assert (k**(-n)).is_integer is None assert (k**x).is_integer is None assert (x**k).is_integer is None assert (k**(n*m)).is_integer is True assert (k**(-n*m)).is_integer is None assert sqrt(3).is_integer is False assert sqrt(.3).is_integer is False assert Pow(3, 2, evaluate=False).is_integer is True assert Pow(3, 0, evaluate=False).is_integer is True assert Pow(3, -2, evaluate=False).is_integer is False assert Pow(S.Half, 3, evaluate=False).is_integer is False # decided by re-evaluating assert Pow(3, S.Half, evaluate=False).is_integer is False assert Pow(3, S.Half, evaluate=False).is_integer is False assert Pow(4, S.Half, evaluate=False).is_integer is True assert Pow(S.Half, -2, evaluate=False).is_integer is True assert ((-1)**k).is_integer # issue 8641 x = Symbol('x', real=True, integer=False) assert (x**2).is_integer is None # issue 10458 x = Symbol('x', positive=True) assert (1/(x + 1)).is_integer is False assert (1/(-x - 1)).is_integer is False def test_Pow_is_real(): x = Symbol('x', real=True) y = Symbol('y', real=True, positive=True) assert (x**2).is_real is True assert (x**3).is_real is True assert (x**x).is_real is None assert (y**x).is_real is True assert (x**Rational(1, 3)).is_real is None assert (y**Rational(1, 3)).is_real is True assert sqrt(-1 - sqrt(2)).is_real is False i = Symbol('i', imaginary=True) assert (i**i).is_real is None assert (I**i).is_extended_real is True assert ((-I)**i).is_extended_real is True assert (2**i).is_real is None # (2**(pi/log(2) * I)) is real, 2**I is not assert (2**I).is_real is False assert (2**-I).is_real is False assert (i**2).is_extended_real is True assert (i**3).is_extended_real is False assert (i**x).is_real is None # could be (-I)**(2/3) e = Symbol('e', even=True) o = Symbol('o', odd=True) k = Symbol('k', integer=True) assert (i**e).is_extended_real is True assert (i**o).is_extended_real is False assert (i**k).is_real is None assert (i**(4*k)).is_extended_real is True x = Symbol("x", nonnegative=True) y = Symbol("y", nonnegative=True) assert im(x**y).expand(complex=True) is S.Zero assert (x**y).is_real is True i = Symbol('i', imaginary=True) assert (exp(i)**I).is_extended_real is True assert log(exp(i)).is_imaginary is None # i could be 2*pi*I c = Symbol('c', complex=True) assert log(c).is_real is None # c could be 0 or 2, too assert log(exp(c)).is_real is None # log(0), log(E), ... n = Symbol('n', negative=False) assert log(n).is_real is None n = Symbol('n', nonnegative=True) assert log(n).is_real is None assert sqrt(-I).is_real is False # issue 7843 i = Symbol('i', integer=True) assert (1/(i-1)).is_real is None assert (1/(i-1)).is_extended_real is None # test issue 20715 from sympy.core.parameters import evaluate x = S(-1) with evaluate(False): assert x.is_negative is True f = Pow(x, -1) with evaluate(False): assert f.is_imaginary is False def test_real_Pow(): k = Symbol('k', integer=True, nonzero=True) assert (k**(I*pi/log(k))).is_real def test_Pow_is_finite(): xe = Symbol('xe', extended_real=True) xr = Symbol('xr', real=True) p = Symbol('p', positive=True) n = Symbol('n', negative=True) i = Symbol('i', integer=True) assert (xe**2).is_finite is None # xe could be oo assert (xr**2).is_finite is True assert (xe**xe).is_finite is None assert (xr**xe).is_finite is None assert (xe**xr).is_finite is None # FIXME: The line below should be True rather than None # assert (xr**xr).is_finite is True assert (xr**xr).is_finite is None assert (p**xe).is_finite is None assert (p**xr).is_finite is True assert (n**xe).is_finite is None assert (n**xr).is_finite is True assert (sin(xe)**2).is_finite is True assert (sin(xr)**2).is_finite is True assert (sin(xe)**xe).is_finite is None # xe, xr could be -pi assert (sin(xr)**xr).is_finite is None # FIXME: Should the line below be True rather than None? assert (sin(xe)**exp(xe)).is_finite is None assert (sin(xr)**exp(xr)).is_finite is True assert (1/sin(xe)).is_finite is None # if zero, no, otherwise yes assert (1/sin(xr)).is_finite is None assert (1/exp(xe)).is_finite is None # xe could be -oo assert (1/exp(xr)).is_finite is True assert (1/S.Pi).is_finite is True assert (1/(i-1)).is_finite is None def test_Pow_is_even_odd(): x = Symbol('x') k = Symbol('k', even=True) n = Symbol('n', odd=True) m = Symbol('m', integer=True, nonnegative=True) p = Symbol('p', integer=True, positive=True) assert ((-1)**n).is_odd assert ((-1)**k).is_odd assert ((-1)**(m - p)).is_odd assert (k**2).is_even is True assert (n**2).is_even is False assert (2**k).is_even is None assert (x**2).is_even is None assert (k**m).is_even is None assert (n**m).is_even is False assert (k**p).is_even is True assert (n**p).is_even is False assert (m**k).is_even is None assert (p**k).is_even is None assert (m**n).is_even is None assert (p**n).is_even is None assert (k**x).is_even is None assert (n**x).is_even is None assert (k**2).is_odd is False assert (n**2).is_odd is True assert (3**k).is_odd is None assert (k**m).is_odd is None assert (n**m).is_odd is True assert (k**p).is_odd is False assert (n**p).is_odd is True assert (m**k).is_odd is None assert (p**k).is_odd is None assert (m**n).is_odd is None assert (p**n).is_odd is None assert (k**x).is_odd is None assert (n**x).is_odd is None def test_Pow_is_negative_positive(): r = Symbol('r', real=True) k = Symbol('k', integer=True, positive=True) n = Symbol('n', even=True) m = Symbol('m', odd=True) x = Symbol('x') assert (2**r).is_positive is True assert ((-2)**r).is_positive is None assert ((-2)**n).is_positive is True assert ((-2)**m).is_positive is False assert (k**2).is_positive is True assert (k**(-2)).is_positive is True assert (k**r).is_positive is True assert ((-k)**r).is_positive is None assert ((-k)**n).is_positive is True assert ((-k)**m).is_positive is False assert (2**r).is_negative is False assert ((-2)**r).is_negative is None assert ((-2)**n).is_negative is False assert ((-2)**m).is_negative is True assert (k**2).is_negative is False assert (k**(-2)).is_negative is False assert (k**r).is_negative is False assert ((-k)**r).is_negative is None assert ((-k)**n).is_negative is False assert ((-k)**m).is_negative is True assert (2**x).is_positive is None assert (2**x).is_negative is None def test_Pow_is_zero(): z = Symbol('z', zero=True) e = z**2 assert e.is_zero assert e.is_positive is False assert e.is_negative is False assert Pow(0, 0, evaluate=False).is_zero is False assert Pow(0, 3, evaluate=False).is_zero assert Pow(0, oo, evaluate=False).is_zero assert Pow(0, -3, evaluate=False).is_zero is False assert Pow(0, -oo, evaluate=False).is_zero is False assert Pow(2, 2, evaluate=False).is_zero is False a = Symbol('a', zero=False) assert Pow(a, 3).is_zero is False # issue 7965 assert Pow(2, oo, evaluate=False).is_zero is False assert Pow(2, -oo, evaluate=False).is_zero assert Pow(S.Half, oo, evaluate=False).is_zero assert Pow(S.Half, -oo, evaluate=False).is_zero is False # All combinations of real/complex base/exponent h = S.Half T = True F = False N = None pow_iszero = [ ['**', 0, h, 1, 2, -h, -1,-2,-2*I,-I/2,I/2,1+I,oo,-oo,zoo], [ 0, F, T, T, T, F, F, F, F, F, F, N, T, F, N], [ h, F, F, F, F, F, F, F, F, F, F, F, T, F, N], [ 1, F, F, F, F, F, F, F, F, F, F, F, F, F, N], [ 2, F, F, F, F, F, F, F, F, F, F, F, F, T, N], [ -h, F, F, F, F, F, F, F, F, F, F, F, T, F, N], [ -1, F, F, F, F, F, F, F, F, F, F, F, F, F, N], [ -2, F, F, F, F, F, F, F, F, F, F, F, F, T, N], [-2*I, F, F, F, F, F, F, F, F, F, F, F, F, T, N], [-I/2, F, F, F, F, F, F, F, F, F, F, F, T, F, N], [ I/2, F, F, F, F, F, F, F, F, F, F, F, T, F, N], [ 1+I, F, F, F, F, F, F, F, F, F, F, F, F, T, N], [ oo, F, F, F, F, T, T, T, F, F, F, F, F, T, N], [ -oo, F, F, F, F, T, T, T, F, F, F, F, F, T, N], [ zoo, F, F, F, F, T, T, T, N, N, N, N, F, T, N] ] def test_table(table): n = len(table[0]) for row in range(1, n): base = table[row][0] for col in range(1, n): exp = table[0][col] is_zero = table[row][col] # The actual test here: assert Pow(base, exp, evaluate=False).is_zero is is_zero test_table(pow_iszero) # A zero symbol... zo, zo2 = symbols('zo, zo2', zero=True) # All combinations of finite symbols zf, zf2 = symbols('zf, zf2', finite=True) wf, wf2 = symbols('wf, wf2', nonzero=True) xf, xf2 = symbols('xf, xf2', real=True) yf, yf2 = symbols('yf, yf2', nonzero=True) af, af2 = symbols('af, af2', positive=True) bf, bf2 = symbols('bf, bf2', nonnegative=True) cf, cf2 = symbols('cf, cf2', negative=True) df, df2 = symbols('df, df2', nonpositive=True) # Without finiteness: zi, zi2 = symbols('zi, zi2') wi, wi2 = symbols('wi, wi2', zero=False) xi, xi2 = symbols('xi, xi2', extended_real=True) yi, yi2 = symbols('yi, yi2', zero=False, extended_real=True) ai, ai2 = symbols('ai, ai2', extended_positive=True) bi, bi2 = symbols('bi, bi2', extended_nonnegative=True) ci, ci2 = symbols('ci, ci2', extended_negative=True) di, di2 = symbols('di, di2', extended_nonpositive=True) pow_iszero_sym = [ ['**',zo,wf,yf,af,cf,zf,xf,bf,df,zi,wi,xi,yi,ai,bi,ci,di], [ zo2, F, N, N, T, F, N, N, N, F, N, N, N, N, T, N, F, F], [ wf2, F, F, F, F, F, F, F, F, F, N, N, N, N, N, N, N, N], [ yf2, F, F, F, F, F, F, F, F, F, N, N, N, N, N, N, N, N], [ af2, F, F, F, F, F, F, F, F, F, N, N, N, N, N, N, N, N], [ cf2, F, F, F, F, F, F, F, F, F, N, N, N, N, N, N, N, N], [ zf2, N, N, N, N, F, N, N, N, N, N, N, N, N, N, N, N, N], [ xf2, N, N, N, N, F, N, N, N, N, N, N, N, N, N, N, N, N], [ bf2, N, N, N, N, F, N, N, N, N, N, N, N, N, N, N, N, N], [ df2, N, N, N, N, F, N, N, N, N, N, N, N, N, N, N, N, N], [ zi2, N, N, N, N, N, N, N, N, N, N, N, N, N, N, N, N, N], [ wi2, F, N, N, F, N, N, N, F, N, N, N, N, N, N, N, N, N], [ xi2, N, N, N, N, N, N, N, N, N, N, N, N, N, N, N, N, N], [ yi2, F, N, N, F, N, N, N, F, N, N, N, N, N, N, N, N, N], [ ai2, F, N, N, F, N, N, N, F, N, N, N, N, N, N, N, N, N], [ bi2, N, N, N, N, N, N, N, N, N, N, N, N, N, N, N, N, N], [ ci2, F, N, N, F, N, N, N, F, N, N, N, N, N, N, N, N, N], [ di2, N, N, N, N, N, N, N, N, N, N, N, N, N, N, N, N, N] ] test_table(pow_iszero_sym) # In some cases (x**x).is_zero is different from (x**y).is_zero even if y # has the same assumptions as x. assert (zo ** zo).is_zero is False assert (wf ** wf).is_zero is False assert (yf ** yf).is_zero is False assert (af ** af).is_zero is False assert (cf ** cf).is_zero is False assert (zf ** zf).is_zero is None assert (xf ** xf).is_zero is None assert (bf ** bf).is_zero is False # None in table assert (df ** df).is_zero is None assert (zi ** zi).is_zero is None assert (wi ** wi).is_zero is None assert (xi ** xi).is_zero is None assert (yi ** yi).is_zero is None assert (ai ** ai).is_zero is False # None in table assert (bi ** bi).is_zero is False # None in table assert (ci ** ci).is_zero is None assert (di ** di).is_zero is None def test_Pow_is_nonpositive_nonnegative(): x = Symbol('x', real=True) k = Symbol('k', integer=True, nonnegative=True) l = Symbol('l', integer=True, positive=True) n = Symbol('n', even=True) m = Symbol('m', odd=True) assert (x**(4*k)).is_nonnegative is True assert (2**x).is_nonnegative is True assert ((-2)**x).is_nonnegative is None assert ((-2)**n).is_nonnegative is True assert ((-2)**m).is_nonnegative is False assert (k**2).is_nonnegative is True assert (k**(-2)).is_nonnegative is None assert (k**k).is_nonnegative is True assert (k**x).is_nonnegative is None # NOTE (0**x).is_real = U assert (l**x).is_nonnegative is True assert (l**x).is_positive is True assert ((-k)**x).is_nonnegative is None assert ((-k)**m).is_nonnegative is None assert (2**x).is_nonpositive is False assert ((-2)**x).is_nonpositive is None assert ((-2)**n).is_nonpositive is False assert ((-2)**m).is_nonpositive is True assert (k**2).is_nonpositive is None assert (k**(-2)).is_nonpositive is None assert (k**x).is_nonpositive is None assert ((-k)**x).is_nonpositive is None assert ((-k)**n).is_nonpositive is None assert (x**2).is_nonnegative is True i = symbols('i', imaginary=True) assert (i**2).is_nonpositive is True assert (i**4).is_nonpositive is False assert (i**3).is_nonpositive is False assert (I**i).is_nonnegative is True assert (exp(I)**i).is_nonnegative is True assert ((-l)**n).is_nonnegative is True assert ((-l)**m).is_nonpositive is True assert ((-k)**n).is_nonnegative is None assert ((-k)**m).is_nonpositive is None def test_Mul_is_imaginary_real(): r = Symbol('r', real=True) p = Symbol('p', positive=True) i1 = Symbol('i1', imaginary=True) i2 = Symbol('i2', imaginary=True) x = Symbol('x') assert I.is_imaginary is True assert I.is_real is False assert (-I).is_imaginary is True assert (-I).is_real is False assert (3*I).is_imaginary is True assert (3*I).is_real is False assert (I*I).is_imaginary is False assert (I*I).is_real is True e = (p + p*I) j = Symbol('j', integer=True, zero=False) assert (e**j).is_real is None assert (e**(2*j)).is_real is None assert (e**j).is_imaginary is None assert (e**(2*j)).is_imaginary is None assert (e**-1).is_imaginary is False assert (e**2).is_imaginary assert (e**3).is_imaginary is False assert (e**4).is_imaginary is False assert (e**5).is_imaginary is False assert (e**-1).is_real is False assert (e**2).is_real is False assert (e**3).is_real is False assert (e**4).is_real is True assert (e**5).is_real is False assert (e**3).is_complex assert (r*i1).is_imaginary is None assert (r*i1).is_real is None assert (x*i1).is_imaginary is None assert (x*i1).is_real is None assert (i1*i2).is_imaginary is False assert (i1*i2).is_real is True assert (r*i1*i2).is_imaginary is False assert (r*i1*i2).is_real is True # Github's issue 5874: nr = Symbol('nr', real=False, complex=True) # e.g. I or 1 + I a = Symbol('a', real=True, nonzero=True) b = Symbol('b', real=True) assert (i1*nr).is_real is None assert (a*nr).is_real is False assert (b*nr).is_real is None ni = Symbol('ni', imaginary=False, complex=True) # e.g. 2 or 1 + I a = Symbol('a', real=True, nonzero=True) b = Symbol('b', real=True) assert (i1*ni).is_real is False assert (a*ni).is_real is None assert (b*ni).is_real is None def test_Mul_hermitian_antihermitian(): a = Symbol('a', hermitian=True, zero=False) b = Symbol('b', hermitian=True) c = Symbol('c', hermitian=False) d = Symbol('d', antihermitian=True) e1 = Mul(a, b, c, evaluate=False) e2 = Mul(b, a, c, evaluate=False) e3 = Mul(a, b, c, d, evaluate=False) e4 = Mul(b, a, c, d, evaluate=False) e5 = Mul(a, c, evaluate=False) e6 = Mul(a, c, d, evaluate=False) assert e1.is_hermitian is None assert e2.is_hermitian is None assert e1.is_antihermitian is None assert e2.is_antihermitian is None assert e3.is_antihermitian is None assert e4.is_antihermitian is None assert e5.is_antihermitian is None assert e6.is_antihermitian is None def test_Add_is_comparable(): assert (x + y).is_comparable is False assert (x + 1).is_comparable is False assert (Rational(1, 3) - sqrt(8)).is_comparable is True def test_Mul_is_comparable(): assert (x*y).is_comparable is False assert (x*2).is_comparable is False assert (sqrt(2)*Rational(1, 3)).is_comparable is True def test_Pow_is_comparable(): assert (x**y).is_comparable is False assert (x**2).is_comparable is False assert (sqrt(Rational(1, 3))).is_comparable is True def test_Add_is_positive_2(): e = Rational(1, 3) - sqrt(8) assert e.is_positive is False assert e.is_negative is True e = pi - 1 assert e.is_positive is True assert e.is_negative is False def test_Add_is_irrational(): i = Symbol('i', irrational=True) assert i.is_irrational is True assert i.is_rational is False assert (i + 1).is_irrational is True assert (i + 1).is_rational is False def test_Mul_is_irrational(): expr = Mul(1, 2, 3, evaluate=False) assert expr.is_irrational is False expr = Mul(1, I, I, evaluate=False) assert expr.is_rational is None # I * I = -1 but *no evaluation allowed* # sqrt(2) * I * I = -sqrt(2) is irrational but # this can't be determined without evaluating the # expression and the eval_is routines shouldn't do that expr = Mul(sqrt(2), I, I, evaluate=False) assert expr.is_irrational is None def test_issue_3531(): # https://github.com/sympy/sympy/issues/3531 # https://github.com/sympy/sympy/pull/18116 class MightyNumeric(tuple): def __rtruediv__(self, other): return "something" assert sympify(1)/MightyNumeric((1, 2)) == "something" def test_issue_3531b(): class Foo: def __init__(self): self.field = 1.0 def __mul__(self, other): self.field = self.field * other def __rmul__(self, other): self.field = other * self.field f = Foo() x = Symbol("x") assert f*x == x*f def test_bug3(): a = Symbol("a") b = Symbol("b", positive=True) e = 2*a + b f = b + 2*a assert e == f def test_suppressed_evaluation(): a = Add(0, 3, 2, evaluate=False) b = Mul(1, 3, 2, evaluate=False) c = Pow(3, 2, evaluate=False) assert a != 6 assert a.func is Add assert a.args == (0, 3, 2) assert b != 6 assert b.func is Mul assert b.args == (1, 3, 2) assert c != 9 assert c.func is Pow assert c.args == (3, 2) def test_AssocOp_doit(): a = Add(x,x, evaluate=False) b = Mul(y,y, evaluate=False) c = Add(b,b, evaluate=False) d = Mul(a,a, evaluate=False) assert c.doit(deep=False).func == Mul assert c.doit(deep=False).args == (2,y,y) assert c.doit().func == Mul assert c.doit().args == (2, Pow(y,2)) assert d.doit(deep=False).func == Pow assert d.doit(deep=False).args == (a, 2*S.One) assert d.doit().func == Mul assert d.doit().args == (4*S.One, Pow(x,2)) def test_Add_Mul_Expr_args(): nonexpr = [Basic(), Poly(x, x), FiniteSet(x)] for typ in [Add, Mul]: for obj in nonexpr: with warns_deprecated_sympy(): typ(obj, 1) def test_Add_as_coeff_mul(): # issue 5524. These should all be (1, self) assert (x + 1).as_coeff_mul() == (1, (x + 1,)) assert (x + 2).as_coeff_mul() == (1, (x + 2,)) assert (x + 3).as_coeff_mul() == (1, (x + 3,)) assert (x - 1).as_coeff_mul() == (1, (x - 1,)) assert (x - 2).as_coeff_mul() == (1, (x - 2,)) assert (x - 3).as_coeff_mul() == (1, (x - 3,)) n = Symbol('n', integer=True) assert (n + 1).as_coeff_mul() == (1, (n + 1,)) assert (n + 2).as_coeff_mul() == (1, (n + 2,)) assert (n + 3).as_coeff_mul() == (1, (n + 3,)) assert (n - 1).as_coeff_mul() == (1, (n - 1,)) assert (n - 2).as_coeff_mul() == (1, (n - 2,)) assert (n - 3).as_coeff_mul() == (1, (n - 3,)) def test_Pow_as_coeff_mul_doesnt_expand(): assert exp(x + y).as_coeff_mul() == (1, (exp(x + y),)) assert exp(x + exp(x + y)) != exp(x + exp(x)*exp(y)) def test_issue_3514_18626(): assert sqrt(S.Half) * sqrt(6) == 2 * sqrt(3)/2 assert S.Half*sqrt(6)*sqrt(2) == sqrt(3) assert sqrt(6)/2*sqrt(2) == sqrt(3) assert sqrt(6)*sqrt(2)/2 == sqrt(3) assert sqrt(8)**Rational(2, 3) == 2 def test_make_args(): assert Add.make_args(x) == (x,) assert Mul.make_args(x) == (x,) assert Add.make_args(x*y*z) == (x*y*z,) assert Mul.make_args(x*y*z) == (x*y*z).args assert Add.make_args(x + y + z) == (x + y + z).args assert Mul.make_args(x + y + z) == (x + y + z,) assert Add.make_args((x + y)**z) == ((x + y)**z,) assert Mul.make_args((x + y)**z) == ((x + y)**z,) def test_issue_5126(): assert (-2)**x*(-3)**x != 6**x i = Symbol('i', integer=1) assert (-2)**i*(-3)**i == 6**i def test_Rational_as_content_primitive(): c, p = S.One, S.Zero assert (c*p).as_content_primitive() == (c, p) c, p = S.Half, S.One assert (c*p).as_content_primitive() == (c, p) def test_Add_as_content_primitive(): assert (x + 2).as_content_primitive() == (1, x + 2) assert (3*x + 2).as_content_primitive() == (1, 3*x + 2) assert (3*x + 3).as_content_primitive() == (3, x + 1) assert (3*x + 6).as_content_primitive() == (3, x + 2) assert (3*x + 2*y).as_content_primitive() == (1, 3*x + 2*y) assert (3*x + 3*y).as_content_primitive() == (3, x + y) assert (3*x + 6*y).as_content_primitive() == (3, x + 2*y) assert (3/x + 2*x*y*z**2).as_content_primitive() == (1, 3/x + 2*x*y*z**2) assert (3/x + 3*x*y*z**2).as_content_primitive() == (3, 1/x + x*y*z**2) assert (3/x + 6*x*y*z**2).as_content_primitive() == (3, 1/x + 2*x*y*z**2) assert (2*x/3 + 4*y/9).as_content_primitive() == \ (Rational(2, 9), 3*x + 2*y) assert (2*x/3 + 2.5*y).as_content_primitive() == \ (Rational(1, 3), 2*x + 7.5*y) # the coefficient may sort to a position other than 0 p = 3 + x + y assert (2*p).expand().as_content_primitive() == (2, p) assert (2.0*p).expand().as_content_primitive() == (1, 2.*p) p *= -1 assert (2*p).expand().as_content_primitive() == (2, p) def test_Mul_as_content_primitive(): assert (2*x).as_content_primitive() == (2, x) assert (x*(2 + 2*x)).as_content_primitive() == (2, x*(1 + x)) assert (x*(2 + 2*y)*(3*x + 3)**2).as_content_primitive() == \ (18, x*(1 + y)*(x + 1)**2) assert ((2 + 2*x)**2*(3 + 6*x) + S.Half).as_content_primitive() == \ (S.Half, 24*(x + 1)**2*(2*x + 1) + 1) def test_Pow_as_content_primitive(): assert (x**y).as_content_primitive() == (1, x**y) assert ((2*x + 2)**y).as_content_primitive() == \ (1, (Mul(2, (x + 1), evaluate=False))**y) assert ((2*x + 2)**3).as_content_primitive() == (8, (x + 1)**3) def test_issue_5460(): u = Mul(2, (1 + x), evaluate=False) assert (2 + u).args == (2, u) def test_product_irrational(): assert (I*pi).is_irrational is False # The following used to be deduced from the above bug: assert (I*pi).is_positive is False def test_issue_5919(): assert (x/(y*(1 + y))).expand() == x/(y**2 + y) def test_Mod(): assert Mod(x, 1).func is Mod assert pi % pi is S.Zero assert Mod(5, 3) == 2 assert Mod(-5, 3) == 1 assert Mod(5, -3) == -1 assert Mod(-5, -3) == -2 assert type(Mod(3.2, 2, evaluate=False)) == Mod assert 5 % x == Mod(5, x) assert x % 5 == Mod(x, 5) assert x % y == Mod(x, y) assert (x % y).subs({x: 5, y: 3}) == 2 assert Mod(nan, 1) is nan assert Mod(1, nan) is nan assert Mod(nan, nan) is nan Mod(0, x) == 0 with raises(ZeroDivisionError): Mod(x, 0) k = Symbol('k', integer=True) m = Symbol('m', integer=True, positive=True) assert (x**m % x).func is Mod assert (k**(-m) % k).func is Mod assert k**m % k == 0 assert (-2*k)**m % k == 0 # Float handling point3 = Float(3.3) % 1 assert (x - 3.3) % 1 == Mod(1.*x + 1 - point3, 1) assert Mod(-3.3, 1) == 1 - point3 assert Mod(0.7, 1) == Float(0.7) e = Mod(1.3, 1) assert comp(e, .3) and e.is_Float e = Mod(1.3, .7) assert comp(e, .6) and e.is_Float e = Mod(1.3, Rational(7, 10)) assert comp(e, .6) and e.is_Float e = Mod(Rational(13, 10), 0.7) assert comp(e, .6) and e.is_Float e = Mod(Rational(13, 10), Rational(7, 10)) assert comp(e, .6) and e.is_Rational # check that sign is right r2 = sqrt(2) r3 = sqrt(3) for i in [-r3, -r2, r2, r3]: for j in [-r3, -r2, r2, r3]: assert verify_numerically(i % j, i.n() % j.n()) for _x in range(4): for _y in range(9): reps = [(x, _x), (y, _y)] assert Mod(3*x + y, 9).subs(reps) == (3*_x + _y) % 9 # denesting t = Symbol('t', real=True) assert Mod(Mod(x, t), t) == Mod(x, t) assert Mod(-Mod(x, t), t) == Mod(-x, t) assert Mod(Mod(x, 2*t), t) == Mod(x, t) assert Mod(-Mod(x, 2*t), t) == Mod(-x, t) assert Mod(Mod(x, t), 2*t) == Mod(x, t) assert Mod(-Mod(x, t), -2*t) == -Mod(x, t) for i in [-4, -2, 2, 4]: for j in [-4, -2, 2, 4]: for k in range(4): assert Mod(Mod(x, i), j).subs({x: k}) == (k % i) % j assert Mod(-Mod(x, i), j).subs({x: k}) == -(k % i) % j # known difference assert Mod(5*sqrt(2), sqrt(5)) == 5*sqrt(2) - 3*sqrt(5) p = symbols('p', positive=True) assert Mod(2, p + 3) == 2 assert Mod(-2, p + 3) == p + 1 assert Mod(2, -p - 3) == -p - 1 assert Mod(-2, -p - 3) == -2 assert Mod(p + 5, p + 3) == 2 assert Mod(-p - 5, p + 3) == p + 1 assert Mod(p + 5, -p - 3) == -p - 1 assert Mod(-p - 5, -p - 3) == -2 assert Mod(p + 1, p - 1).func is Mod # handling sums assert (x + 3) % 1 == Mod(x, 1) assert (x + 3.0) % 1 == Mod(1.*x, 1) assert (x - S(33)/10) % 1 == Mod(x + S(7)/10, 1) a = Mod(.6*x + y, .3*y) b = Mod(0.1*y + 0.6*x, 0.3*y) # Test that a, b are equal, with 1e-14 accuracy in coefficients eps = 1e-14 assert abs((a.args[0] - b.args[0]).subs({x: 1, y: 1})) < eps assert abs((a.args[1] - b.args[1]).subs({x: 1, y: 1})) < eps assert (x + 1) % x == 1 % x assert (x + y) % x == y % x assert (x + y + 2) % x == (y + 2) % x assert (a + 3*x + 1) % (2*x) == Mod(a + x + 1, 2*x) assert (12*x + 18*y) % (3*x) == 3*Mod(6*y, x) # gcd extraction assert (-3*x) % (-2*y) == -Mod(3*x, 2*y) assert (.6*pi) % (.3*x*pi) == 0.3*pi*Mod(2, x) assert (.6*pi) % (.31*x*pi) == pi*Mod(0.6, 0.31*x) assert (6*pi) % (.3*x*pi) == 0.3*pi*Mod(20, x) assert (6*pi) % (.31*x*pi) == pi*Mod(6, 0.31*x) assert (6*pi) % (.42*x*pi) == pi*Mod(6, 0.42*x) assert (12*x) % (2*y) == 2*Mod(6*x, y) assert (12*x) % (3*5*y) == 3*Mod(4*x, 5*y) assert (12*x) % (15*x*y) == 3*x*Mod(4, 5*y) assert (-2*pi) % (3*pi) == pi assert (2*x + 2) % (x + 1) == 0 assert (x*(x + 1)) % (x + 1) == (x + 1)*Mod(x, 1) assert Mod(5.0*x, 0.1*y) == 0.1*Mod(50*x, y) i = Symbol('i', integer=True) assert (3*i*x) % (2*i*y) == i*Mod(3*x, 2*y) assert Mod(4*i, 4) == 0 # issue 8677 n = Symbol('n', integer=True, positive=True) assert factorial(n) % n == 0 assert factorial(n + 2) % n == 0 assert (factorial(n + 4) % (n + 5)).func is Mod # Wilson's theorem factorial(18042, evaluate=False) % 18043 == 18042 p = Symbol('n', prime=True) factorial(p - 1) % p == p - 1 factorial(p - 1) % -p == -1 (factorial(3, evaluate=False) % 4).doit() == 2 n = Symbol('n', composite=True, odd=True) factorial(n - 1) % n == 0 # symbolic with known parity n = Symbol('n', even=True) assert Mod(n, 2) == 0 n = Symbol('n', odd=True) assert Mod(n, 2) == 1 # issue 10963 assert (x**6000%400).args[1] == 400 #issue 13543 assert Mod(Mod(x + 1, 2) + 1 , 2) == Mod(x,2) assert Mod(Mod(x + 2, 4)*(x + 4), 4) == Mod(x*(x + 2), 4) assert Mod(Mod(x + 2, 4)*4, 4) == 0 # issue 15493 i, j = symbols('i j', integer=True, positive=True) assert Mod(3*i, 2) == Mod(i, 2) assert Mod(8*i/j, 4) == 4*Mod(2*i/j, 1) assert Mod(8*i, 4) == 0 # rewrite assert Mod(x, y).rewrite(floor) == x - y*floor(x/y) assert ((x - Mod(x, y))/y).rewrite(floor) == floor(x/y) # issue 21373 from sympy.functions.elementary.trigonometric import sinh from sympy.functions.elementary.piecewise import Piecewise x_r, y_r = symbols('x_r y_r', real=True) (Piecewise((x_r, y_r > x_r), (y_r, True)) / z) % 1 expr = exp(sinh(Piecewise((x_r, y_r > x_r), (y_r, True)) / z)) expr.subs({1: 1.0}) sinh(Piecewise((x_r, y_r > x_r), (y_r, True)) * z ** -1.0).is_zero def test_Mod_Pow(): # modular exponentiation assert isinstance(Mod(Pow(2, 2, evaluate=False), 3), Integer) assert Mod(Pow(4, 13, evaluate=False), 497) == Mod(Pow(4, 13), 497) assert Mod(Pow(2, 10000000000, evaluate=False), 3) == 1 assert Mod(Pow(32131231232, 9**10**6, evaluate=False),10**12) == \ pow(32131231232,9**10**6,10**12) assert Mod(Pow(33284959323, 123**999, evaluate=False),11**13) == \ pow(33284959323,123**999,11**13) assert Mod(Pow(78789849597, 333**555, evaluate=False),12**9) == \ pow(78789849597,333**555,12**9) # modular nested exponentiation expr = Pow(2, 2, evaluate=False) expr = Pow(2, expr, evaluate=False) assert Mod(expr, 3**10) == 16 expr = Pow(2, expr, evaluate=False) assert Mod(expr, 3**10) == 6487 expr = Pow(2, expr, evaluate=False) assert Mod(expr, 3**10) == 32191 expr = Pow(2, expr, evaluate=False) assert Mod(expr, 3**10) == 18016 expr = Pow(2, expr, evaluate=False) assert Mod(expr, 3**10) == 5137 expr = Pow(2, 2, evaluate=False) expr = Pow(expr, 2, evaluate=False) assert Mod(expr, 3**10) == 16 expr = Pow(expr, 2, evaluate=False) assert Mod(expr, 3**10) == 256 expr = Pow(expr, 2, evaluate=False) assert Mod(expr, 3**10) == 6487 expr = Pow(expr, 2, evaluate=False) assert Mod(expr, 3**10) == 38281 expr = Pow(expr, 2, evaluate=False) assert Mod(expr, 3**10) == 15928 expr = Pow(2, 2, evaluate=False) expr = Pow(expr, expr, evaluate=False) assert Mod(expr, 3**10) == 256 expr = Pow(expr, expr, evaluate=False) assert Mod(expr, 3**10) == 9229 expr = Pow(expr, expr, evaluate=False) assert Mod(expr, 3**10) == 25708 expr = Pow(expr, expr, evaluate=False) assert Mod(expr, 3**10) == 26608 expr = Pow(expr, expr, evaluate=False) # XXX This used to fail in a nondeterministic way because of overflow # error. assert Mod(expr, 3**10) == 1966 def test_Mod_is_integer(): p = Symbol('p', integer=True) q1 = Symbol('q1', integer=True) q2 = Symbol('q2', integer=True, nonzero=True) assert Mod(x, y).is_integer is None assert Mod(p, q1).is_integer is None assert Mod(x, q2).is_integer is None assert Mod(p, q2).is_integer def test_Mod_is_nonposneg(): n = Symbol('n', integer=True) k = Symbol('k', integer=True, positive=True) assert (n%3).is_nonnegative assert Mod(n, -3).is_nonpositive assert Mod(n, k).is_nonnegative assert Mod(n, -k).is_nonpositive assert Mod(k, n).is_nonnegative is None def test_issue_6001(): A = Symbol("A", commutative=False) eq = A + A**2 # it doesn't matter whether it's True or False; they should # just all be the same assert ( eq.is_commutative == (eq + 1).is_commutative == (A + 1).is_commutative) B = Symbol("B", commutative=False) # Although commutative terms could cancel we return True # meaning "there are non-commutative symbols; aftersubstitution # that definition can change, e.g. (A*B).subs(B,A**-1) -> 1 assert (sqrt(2)*A).is_commutative is False assert (sqrt(2)*A*B).is_commutative is False def test_polar(): from sympy import polar_lift p = Symbol('p', polar=True) x = Symbol('x') assert p.is_polar assert x.is_polar is None assert S.One.is_polar is None assert (p**x).is_polar is True assert (x**p).is_polar is None assert ((2*p)**x).is_polar is True assert (2*p).is_polar is True assert (-2*p).is_polar is not True assert (polar_lift(-2)*p).is_polar is True q = Symbol('q', polar=True) assert (p*q)**2 == p**2 * q**2 assert (2*q)**2 == 4 * q**2 assert ((p*q)**x).expand() == p**x * q**x def test_issue_6040(): a, b = Pow(1, 2, evaluate=False), S.One assert a != b assert b != a assert not (a == b) assert not (b == a) def test_issue_6082(): # Comparison is symmetric assert Basic.compare(Max(x, 1), Max(x, 2)) == \ - Basic.compare(Max(x, 2), Max(x, 1)) # Equal expressions compare equal assert Basic.compare(Max(x, 1), Max(x, 1)) == 0 # Basic subtypes (such as Max) compare different than standard types assert Basic.compare(Max(1, x), frozenset((1, x))) != 0 def test_issue_6077(): assert x**2.0/x == x**1.0 assert x/x**2.0 == x**-1.0 assert x*x**2.0 == x**3.0 assert x**1.5*x**2.5 == x**4.0 assert 2**(2.0*x)/2**x == 2**(1.0*x) assert 2**x/2**(2.0*x) == 2**(-1.0*x) assert 2**x*2**(2.0*x) == 2**(3.0*x) assert 2**(1.5*x)*2**(2.5*x) == 2**(4.0*x) def test_mul_flatten_oo(): p = symbols('p', positive=True) n, m = symbols('n,m', negative=True) x_im = symbols('x_im', imaginary=True) assert n*oo is -oo assert n*m*oo is oo assert p*oo is oo assert x_im*oo != I*oo # i could be +/- 3*I -> +/-oo def test_add_flatten(): # see https://github.com/sympy/sympy/issues/2633#issuecomment-29545524 a = oo + I*oo b = oo - I*oo assert a + b is nan assert a - b is nan # FIXME: This evaluates as: # >>> 1/a # 0*(oo + oo*I) # which should not simplify to 0. Should be fixed in Pow.eval #assert (1/a).simplify() == (1/b).simplify() == 0 a = Pow(2, 3, evaluate=False) assert a + a == 16 def test_issue_5160_6087_6089_6090(): # issue 6087 assert ((-2*x*y**y)**3.2).n(2) == (2**3.2*(-x*y**y)**3.2).n(2) # issue 6089 A, B, C = symbols('A,B,C', commutative=False) assert (2.*B*C)**3 == 8.0*(B*C)**3 assert (-2.*B*C)**3 == -8.0*(B*C)**3 assert (-2*B*C)**2 == 4*(B*C)**2 # issue 5160 assert sqrt(-1.0*x) == 1.0*sqrt(-x) assert sqrt(1.0*x) == 1.0*sqrt(x) # issue 6090 assert (-2*x*y*A*B)**2 == 4*x**2*y**2*(A*B)**2 def test_float_int_round(): assert int(float(sqrt(10))) == int(sqrt(10)) assert int(pi**1000) % 10 == 2 assert int(Float('1.123456789012345678901234567890e20', '')) == \ int(112345678901234567890) assert int(Float('1.123456789012345678901234567890e25', '')) == \ int(11234567890123456789012345) # decimal forces float so it's not an exact integer ending in 000000 assert int(Float('1.123456789012345678901234567890e35', '')) == \ 112345678901234567890123456789000192 assert int(Float('123456789012345678901234567890e5', '')) == \ 12345678901234567890123456789000000 assert Integer(Float('1.123456789012345678901234567890e20', '')) == \ 112345678901234567890 assert Integer(Float('1.123456789012345678901234567890e25', '')) == \ 11234567890123456789012345 # decimal forces float so it's not an exact integer ending in 000000 assert Integer(Float('1.123456789012345678901234567890e35', '')) == \ 112345678901234567890123456789000192 assert Integer(Float('123456789012345678901234567890e5', '')) == \ 12345678901234567890123456789000000 assert same_and_same_prec(Float('123000e-2',''), Float('1230.00', '')) assert same_and_same_prec(Float('123000e2',''), Float('12300000', '')) assert int(1 + Rational('.9999999999999999999999999')) == 1 assert int(pi/1e20) == 0 assert int(1 + pi/1e20) == 1 assert int(Add(1.2, -2, evaluate=False)) == int(1.2 - 2) assert int(Add(1.2, +2, evaluate=False)) == int(1.2 + 2) assert int(Add(1 + Float('.99999999999999999', ''), evaluate=False)) == 1 raises(TypeError, lambda: float(x)) raises(TypeError, lambda: float(sqrt(-1))) assert int(12345678901234567890 + cos(1)**2 + sin(1)**2) == \ 12345678901234567891 def test_issue_6611a(): assert Mul.flatten([3**Rational(1, 3), Pow(-Rational(1, 9), Rational(2, 3), evaluate=False)]) == \ ([Rational(1, 3), (-1)**Rational(2, 3)], [], None) def test_denest_add_mul(): # when working with evaluated expressions make sure they denest eq = x + 1 eq = Add(eq, 2, evaluate=False) eq = Add(eq, 2, evaluate=False) assert Add(*eq.args) == x + 5 eq = x*2 eq = Mul(eq, 2, evaluate=False) eq = Mul(eq, 2, evaluate=False) assert Mul(*eq.args) == 8*x # but don't let them denest unecessarily eq = Mul(-2, x - 2, evaluate=False) assert 2*eq == Mul(-4, x - 2, evaluate=False) assert -eq == Mul(2, x - 2, evaluate=False) def test_mul_coeff(): # It is important that all Numbers be removed from the seq; # This can be tricky when powers combine to produce those numbers p = exp(I*pi/3) assert p**2*x*p*y*p*x*p**2 == x**2*y def test_mul_zero_detection(): nz = Dummy(real=True, zero=False) r = Dummy(extended_real=True) c = Dummy(real=False, complex=True) c2 = Dummy(real=False, complex=True) i = Dummy(imaginary=True) e = nz*r*c assert e.is_imaginary is None assert e.is_extended_real is None e = nz*c assert e.is_imaginary is None assert e.is_extended_real is False e = nz*i*c assert e.is_imaginary is False assert e.is_extended_real is None # check for more than one complex; it is important to use # uniquely named Symbols to ensure that two factors appear # e.g. if the symbols have the same name they just become # a single factor, a power. e = nz*i*c*c2 assert e.is_imaginary is None assert e.is_extended_real is None # _eval_is_extended_real and _eval_is_zero both employ trapping of the # zero value so args should be tested in both directions and # TO AVOID GETTING THE CACHED RESULT, Dummy MUST BE USED # real is unknown def test(z, b, e): if z.is_zero and b.is_finite: assert e.is_extended_real and e.is_zero else: assert e.is_extended_real is None if b.is_finite: if z.is_zero: assert e.is_zero else: assert e.is_zero is None elif b.is_finite is False: if z.is_zero is None: assert e.is_zero is None else: assert e.is_zero is False for iz, ib in cartes(*[[True, False, None]]*2): z = Dummy('z', nonzero=iz) b = Dummy('f', finite=ib) e = Mul(z, b, evaluate=False) test(z, b, e) z = Dummy('nz', nonzero=iz) b = Dummy('f', finite=ib) e = Mul(b, z, evaluate=False) test(z, b, e) # real is True def test(z, b, e): if z.is_zero and not b.is_finite: assert e.is_extended_real is None else: assert e.is_extended_real is True for iz, ib in cartes(*[[True, False, None]]*2): z = Dummy('z', nonzero=iz, extended_real=True) b = Dummy('b', finite=ib, extended_real=True) e = Mul(z, b, evaluate=False) test(z, b, e) z = Dummy('z', nonzero=iz, extended_real=True) b = Dummy('b', finite=ib, extended_real=True) e = Mul(b, z, evaluate=False) test(z, b, e) def test_Mul_with_zero_infinite(): zer = Dummy(zero=True) inf = Dummy(finite=False) e = Mul(zer, inf, evaluate=False) assert e.is_extended_positive is None assert e.is_hermitian is None e = Mul(inf, zer, evaluate=False) assert e.is_extended_positive is None assert e.is_hermitian is None def test_Mul_does_not_cancel_infinities(): a, b = symbols('a b') assert ((zoo + 3*a)/(3*a + zoo)) is nan assert ((b - oo)/(b - oo)) is nan # issue 13904 expr = (1/(a+b) + 1/(a-b))/(1/(a+b) - 1/(a-b)) assert expr.subs(b, a) is nan def test_Mul_does_not_distribute_infinity(): a, b = symbols('a b') assert ((1 + I)*oo).is_Mul assert ((a + b)*(-oo)).is_Mul assert ((a + 1)*zoo).is_Mul assert ((1 + I)*oo).is_finite is False z = (1 + I)*oo assert ((1 - I)*z).expand() is oo def test_issue_8247_8354(): from sympy import tan z = sqrt(1 + sqrt(3)) + sqrt(3 + 3*sqrt(3)) - sqrt(10 + 6*sqrt(3)) assert z.is_positive is False # it's 0 z = S('''-2**(1/3)*(3*sqrt(93) + 29)**2 - 4*(3*sqrt(93) + 29)**(4/3) + 12*sqrt(93)*(3*sqrt(93) + 29)**(1/3) + 116*(3*sqrt(93) + 29)**(1/3) + 174*2**(1/3)*sqrt(93) + 1678*2**(1/3)''') assert z.is_positive is False # it's 0 z = 2*(-3*tan(19*pi/90) + sqrt(3))*cos(11*pi/90)*cos(19*pi/90) - \ sqrt(3)*(-3 + 4*cos(19*pi/90)**2) assert z.is_positive is not True # it's zero and it shouldn't hang z = S('''9*(3*sqrt(93) + 29)**(2/3)*((3*sqrt(93) + 29)**(1/3)*(-2**(2/3)*(3*sqrt(93) + 29)**(1/3) - 2) - 2*2**(1/3))**3 + 72*(3*sqrt(93) + 29)**(2/3)*(81*sqrt(93) + 783) + (162*sqrt(93) + 1566)*((3*sqrt(93) + 29)**(1/3)*(-2**(2/3)*(3*sqrt(93) + 29)**(1/3) - 2) - 2*2**(1/3))**2''') assert z.is_positive is False # it's 0 (and a single _mexpand isn't enough) def test_Add_is_zero(): x, y = symbols('x y', zero=True) assert (x + y).is_zero # Issue 15873 e = -2*I + (1 + I)**2 assert e.is_zero is None def test_issue_14392(): assert (sin(zoo)**2).as_real_imag() == (nan, nan) def test_divmod(): assert divmod(x, y) == (x//y, x % y) assert divmod(x, 3) == (x//3, x % 3) assert divmod(3, x) == (3//x, 3 % x) def test__neg__(): assert -(x*y) == -x*y assert -(-x*y) == x*y assert -(1.*x) == -1.*x assert -(-1.*x) == 1.*x assert -(2.*x) == -2.*x assert -(-2.*x) == 2.*x with distribute(False): eq = -(x + y) assert eq.is_Mul and eq.args == (-1, x + y) def test_issue_18507(): assert Mul(zoo, zoo, 0) is nan def test_issue_17130(): e = Add(b, -b, I, -I, evaluate=False) assert e.is_zero is None # ideally this would be True def test_issue_21034(): e = -I*log((re(asin(5)) + I*im(asin(5)))/sqrt(re(asin(5))**2 + im(asin(5))**2))/pi assert e.round(2)
912b57480b6ad5be53937beb1337bbfc4f14327f1b17dd46a21ee157386d6b1d
"""Implementation of :class:`PolynomialRing` class. """ from sympy.polys.domains.ring import Ring from sympy.polys.domains.compositedomain import CompositeDomain from sympy.polys.polyerrors import CoercionFailed, GeneratorsError from sympy.utilities import public @public class PolynomialRing(Ring, CompositeDomain): """A class for representing multivariate polynomial rings. """ is_PolynomialRing = is_Poly = True has_assoc_Ring = True has_assoc_Field = True def __init__(self, domain_or_ring, symbols=None, order=None): from sympy.polys.rings import PolyRing if isinstance(domain_or_ring, PolyRing) and symbols is None and order is None: ring = domain_or_ring else: ring = PolyRing(symbols, domain_or_ring, order) self.ring = ring self.dtype = ring.dtype self.gens = ring.gens self.ngens = ring.ngens self.symbols = ring.symbols self.domain = ring.domain if symbols: if ring.domain.is_Field and ring.domain.is_Exact and len(symbols)==1: self.is_PID = True # TODO: remove this self.dom = self.domain def new(self, element): return self.ring.ring_new(element) @property def zero(self): return self.ring.zero @property def one(self): return self.ring.one @property def order(self): return self.ring.order def __str__(self): return str(self.domain) + '[' + ','.join(map(str, self.symbols)) + ']' def __hash__(self): return hash((self.__class__.__name__, self.dtype.ring, self.domain, self.symbols)) def __eq__(self, other): """Returns `True` if two domains are equivalent. """ return isinstance(other, PolynomialRing) and \ (self.dtype.ring, self.domain, self.symbols) == \ (other.dtype.ring, other.domain, other.symbols) def is_unit(self, a): """Returns ``True`` if ``a`` is a unit of ``self``""" if not a.is_ground: return False K = self.domain return K.is_unit(K.convert_from(a, self)) def canonical_unit(self, a): u = self.domain.canonical_unit(a.LC) return self.ring.ground_new(u) def to_sympy(self, a): """Convert `a` to a SymPy object. """ return a.as_expr() def from_sympy(self, a): """Convert SymPy's expression to `dtype`. """ return self.ring.from_expr(a) def from_ZZ(K1, a, K0): """Convert a Python `int` object to `dtype`. """ return K1(K1.domain.convert(a, K0)) def from_ZZ_python(K1, a, K0): """Convert a Python `int` object to `dtype`. """ return K1(K1.domain.convert(a, K0)) def from_QQ(K1, a, K0): """Convert a Python `Fraction` object to `dtype`. """ return K1(K1.domain.convert(a, K0)) def from_QQ_python(K1, a, K0): """Convert a Python `Fraction` object to `dtype`. """ return K1(K1.domain.convert(a, K0)) def from_ZZ_gmpy(K1, a, K0): """Convert a GMPY `mpz` object to `dtype`. """ return K1(K1.domain.convert(a, K0)) def from_QQ_gmpy(K1, a, K0): """Convert a GMPY `mpq` object to `dtype`. """ return K1(K1.domain.convert(a, K0)) def from_GaussianIntegerRing(K1, a, K0): """Convert a `GaussianInteger` object to `dtype`. """ return K1(K1.domain.convert(a, K0)) def from_GaussianRationalField(K1, a, K0): """Convert a `GaussianRational` object to `dtype`. """ return K1(K1.domain.convert(a, K0)) def from_RealField(K1, a, K0): """Convert a mpmath `mpf` object to `dtype`. """ return K1(K1.domain.convert(a, K0)) def from_ComplexField(K1, a, K0): """Convert a mpmath `mpf` object to `dtype`. """ return K1(K1.domain.convert(a, K0)) def from_AlgebraicField(K1, a, K0): """Convert an algebraic number to ``dtype``. """ if K1.domain != K0: a = K1.domain.convert_from(a, K0) if a is not None: return K1.new(a) def from_PolynomialRing(K1, a, K0): """Convert a polynomial to ``dtype``. """ try: return a.set_ring(K1.ring) except (CoercionFailed, GeneratorsError): return None def from_FractionField(K1, a, K0): """Convert a rational function to ``dtype``. """ if K1.domain == K0: return K1.ring.from_list([a]) q, r = K0.numer(a).div(K0.denom(a)) if r.is_zero: return K1.from_PolynomialRing(q, K0.field.ring.to_domain()) else: return None def from_GlobalPolynomialRing(K1, a, K0): """Convert from old poly ring to ``dtype``. """ if K1.symbols == K0.gens: ad = a.to_dict() if K1.domain != K0.domain: ad = {m: K1.domain.convert(c) for m, c in ad.items()} return K1(ad) elif a.is_ground and K0.domain == K1: return K1.convert_from(a.to_list()[0], K0.domain) def get_field(self): """Returns a field associated with `self`. """ return self.ring.to_field().to_domain() def is_positive(self, a): """Returns True if `LC(a)` is positive. """ return self.domain.is_positive(a.LC) def is_negative(self, a): """Returns True if `LC(a)` is negative. """ return self.domain.is_negative(a.LC) def is_nonpositive(self, a): """Returns True if `LC(a)` is non-positive. """ return self.domain.is_nonpositive(a.LC) def is_nonnegative(self, a): """Returns True if `LC(a)` is non-negative. """ return self.domain.is_nonnegative(a.LC) def gcdex(self, a, b): """Extended GCD of `a` and `b`. """ return a.gcdex(b) def gcd(self, a, b): """Returns GCD of `a` and `b`. """ return a.gcd(b) def lcm(self, a, b): """Returns LCM of `a` and `b`. """ return a.lcm(b) def factorial(self, a): """Returns factorial of `a`. """ return self.dtype(self.domain.factorial(a))
a4a47775f38e5ea048c1fde3bd19daaa003eb7561859db9b0aecf7c8d9f17a95
"""Implementation of :class:`FractionField` class. """ from sympy.polys.domains.compositedomain import CompositeDomain from sympy.polys.domains.field import Field from sympy.polys.polyerrors import CoercionFailed, GeneratorsError from sympy.utilities import public @public class FractionField(Field, CompositeDomain): """A class for representing multivariate rational function fields. """ is_FractionField = is_Frac = True has_assoc_Ring = True has_assoc_Field = True def __init__(self, domain_or_field, symbols=None, order=None): from sympy.polys.fields import FracField if isinstance(domain_or_field, FracField) and symbols is None and order is None: field = domain_or_field else: field = FracField(symbols, domain_or_field, order) self.field = field self.dtype = field.dtype self.gens = field.gens self.ngens = field.ngens self.symbols = field.symbols self.domain = field.domain # TODO: remove this self.dom = self.domain def new(self, element): return self.field.field_new(element) @property def zero(self): return self.field.zero @property def one(self): return self.field.one @property def order(self): return self.field.order @property def is_Exact(self): return self.domain.is_Exact def get_exact(self): return FractionField(self.domain.get_exact(), self.symbols) def __str__(self): return str(self.domain) + '(' + ','.join(map(str, self.symbols)) + ')' def __hash__(self): return hash((self.__class__.__name__, self.dtype.field, self.domain, self.symbols)) def __eq__(self, other): """Returns ``True`` if two domains are equivalent. """ return isinstance(other, FractionField) and \ (self.dtype.field, self.domain, self.symbols) ==\ (other.dtype.field, other.domain, other.symbols) def to_sympy(self, a): """Convert ``a`` to a SymPy object. """ return a.as_expr() def from_sympy(self, a): """Convert SymPy's expression to ``dtype``. """ return self.field.from_expr(a) def from_ZZ(K1, a, K0): """Convert a Python ``int`` object to ``dtype``. """ return K1(K1.domain.convert(a, K0)) def from_ZZ_python(K1, a, K0): """Convert a Python ``int`` object to ``dtype``. """ return K1(K1.domain.convert(a, K0)) def from_QQ(K1, a, K0): """Convert a Python ``Fraction`` object to ``dtype``. """ dom = K1.domain conv = dom.convert_from if dom.is_ZZ: return K1(conv(K0.numer(a), K0)) / K1(conv(K0.denom(a), K0)) else: return K1(conv(a, K0)) def from_QQ_python(K1, a, K0): """Convert a Python ``Fraction`` object to ``dtype``. """ return K1(K1.domain.convert(a, K0)) def from_ZZ_gmpy(K1, a, K0): """Convert a GMPY ``mpz`` object to ``dtype``. """ return K1(K1.domain.convert(a, K0)) def from_QQ_gmpy(K1, a, K0): """Convert a GMPY ``mpq`` object to ``dtype``. """ return K1(K1.domain.convert(a, K0)) def from_GaussianRationalField(K1, a, K0): """Convert a ``GaussianRational`` object to ``dtype``. """ return K1(K1.domain.convert(a, K0)) def from_GaussianIntegerRing(K1, a, K0): """Convert a ``GaussianInteger`` object to ``dtype``. """ return K1(K1.domain.convert(a, K0)) def from_RealField(K1, a, K0): """Convert a mpmath ``mpf`` object to ``dtype``. """ return K1(K1.domain.convert(a, K0)) def from_ComplexField(K1, a, K0): """Convert a mpmath ``mpf`` object to ``dtype``. """ return K1(K1.domain.convert(a, K0)) def from_AlgebraicField(K1, a, K0): """Convert an algebraic number to ``dtype``. """ if K1.domain != K0: a = K1.domain.convert_from(a, K0) if a is not None: return K1.new(a) def from_PolynomialRing(K1, a, K0): """Convert a polynomial to ``dtype``. """ if a.is_ground: return K1.convert_from(a.coeff(1), K0.domain) try: return K1.new(a.set_ring(K1.field.ring)) except (CoercionFailed, GeneratorsError): # XXX: We get here if K1=ZZ(x,y) and K0=QQ[x,y] # and the poly a in K0 has non-integer coefficients. # It seems that K1.new can handle this but K1.new doesn't work # when K0.domain is an algebraic field... try: return K1.new(a) except (CoercionFailed, GeneratorsError): return None def from_FractionField(K1, a, K0): """Convert a rational function to ``dtype``. """ try: return a.set_field(K1.field) except (CoercionFailed, GeneratorsError): return None def get_ring(self): """Returns a field associated with ``self``. """ return self.field.to_ring().to_domain() def is_positive(self, a): """Returns True if ``LC(a)`` is positive. """ return self.domain.is_positive(a.numer.LC) def is_negative(self, a): """Returns True if ``LC(a)`` is negative. """ return self.domain.is_negative(a.numer.LC) def is_nonpositive(self, a): """Returns True if ``LC(a)`` is non-positive. """ return self.domain.is_nonpositive(a.numer.LC) def is_nonnegative(self, a): """Returns True if ``LC(a)`` is non-negative. """ return self.domain.is_nonnegative(a.numer.LC) def numer(self, a): """Returns numerator of ``a``. """ return a.numer def denom(self, a): """Returns denominator of ``a``. """ return a.denom def factorial(self, a): """Returns factorial of ``a``. """ return self.dtype(self.domain.factorial(a))
3636566700dec1a8f86776a046380fca2b7a0a5a23cf72de4d439edf690053f2
"""Implementation of :class:`ExpressionDomain` class. """ from sympy.core import sympify, SympifyError from sympy.polys.domains.characteristiczero import CharacteristicZero from sympy.polys.domains.field import Field from sympy.polys.domains.simpledomain import SimpleDomain from sympy.polys.polyutils import PicklableWithSlots from sympy.utilities import public eflags = dict(deep=False, mul=True, power_exp=False, power_base=False, basic=False, multinomial=False, log=False) @public class ExpressionDomain(Field, CharacteristicZero, SimpleDomain): """A class for arbitrary expressions. """ is_SymbolicDomain = is_EX = True class Expression(PicklableWithSlots): """An arbitrary expression. """ __slots__ = ('ex',) def __init__(self, ex): if not isinstance(ex, self.__class__): self.ex = sympify(ex) else: self.ex = ex.ex def __repr__(f): return 'EX(%s)' % repr(f.ex) def __str__(f): return 'EX(%s)' % str(f.ex) def __hash__(self): return hash((self.__class__.__name__, self.ex)) def as_expr(f): return f.ex def numer(f): return f.__class__(f.ex.as_numer_denom()[0]) def denom(f): return f.__class__(f.ex.as_numer_denom()[1]) def simplify(f, ex): return f.__class__(ex.cancel().expand(**eflags)) def __abs__(f): return f.__class__(abs(f.ex)) def __neg__(f): return f.__class__(-f.ex) def _to_ex(f, g): try: return f.__class__(g) except SympifyError: return None def __add__(f, g): g = f._to_ex(g) if g is None: return NotImplemented elif g == EX.zero: return f elif f == EX.zero: return g else: return f.simplify(f.ex + g.ex) def __radd__(f, g): return f.simplify(f.__class__(g).ex + f.ex) def __sub__(f, g): g = f._to_ex(g) if g is None: return NotImplemented elif g == EX.zero: return f elif f == EX.zero: return -g else: return f.simplify(f.ex - g.ex) def __rsub__(f, g): return f.simplify(f.__class__(g).ex - f.ex) def __mul__(f, g): g = f._to_ex(g) if g is None: return NotImplemented if EX.zero in (f, g): return EX.zero elif f.ex.is_Number and g.ex.is_Number: return f.__class__(f.ex*g.ex) return f.simplify(f.ex*g.ex) def __rmul__(f, g): return f.simplify(f.__class__(g).ex*f.ex) def __pow__(f, n): n = f._to_ex(n) if n is not None: return f.simplify(f.ex**n.ex) else: return NotImplemented def __truediv__(f, g): g = f._to_ex(g) if g is not None: return f.simplify(f.ex/g.ex) else: return NotImplemented def __rtruediv__(f, g): return f.simplify(f.__class__(g).ex/f.ex) def __eq__(f, g): return f.ex == f.__class__(g).ex def __ne__(f, g): return not f == g def __bool__(f): return not f.ex.is_zero def gcd(f, g): from sympy.polys import gcd return f.__class__(gcd(f.ex, f.__class__(g).ex)) def lcm(f, g): from sympy.polys import lcm return f.__class__(lcm(f.ex, f.__class__(g).ex)) dtype = Expression zero = Expression(0) one = Expression(1) rep = 'EX' has_assoc_Ring = False has_assoc_Field = True def __init__(self): pass def to_sympy(self, a): """Convert ``a`` to a SymPy object. """ return a.as_expr() def from_sympy(self, a): """Convert SymPy's expression to ``dtype``. """ return self.dtype(a) def from_ZZ(K1, a, K0): """Convert a Python ``int`` object to ``dtype``. """ return K1(K0.to_sympy(a)) def from_ZZ_python(K1, a, K0): """Convert a Python ``int`` object to ``dtype``. """ return K1(K0.to_sympy(a)) def from_QQ(K1, a, K0): """Convert a Python ``Fraction`` object to ``dtype``. """ return K1(K0.to_sympy(a)) def from_QQ_python(K1, a, K0): """Convert a Python ``Fraction`` object to ``dtype``. """ return K1(K0.to_sympy(a)) def from_ZZ_gmpy(K1, a, K0): """Convert a GMPY ``mpz`` object to ``dtype``. """ return K1(K0.to_sympy(a)) def from_QQ_gmpy(K1, a, K0): """Convert a GMPY ``mpq`` object to ``dtype``. """ return K1(K0.to_sympy(a)) def from_GaussianIntegerRing(K1, a, K0): """Convert a ``GaussianRational`` object to ``dtype``. """ return K1(K0.to_sympy(a)) def from_GaussianRationalField(K1, a, K0): """Convert a ``GaussianRational`` object to ``dtype``. """ return K1(K0.to_sympy(a)) def from_RealField(K1, a, K0): """Convert a mpmath ``mpf`` object to ``dtype``. """ return K1(K0.to_sympy(a)) def from_PolynomialRing(K1, a, K0): """Convert a ``DMP`` object to ``dtype``. """ return K1(K0.to_sympy(a)) def from_FractionField(K1, a, K0): """Convert a ``DMF`` object to ``dtype``. """ return K1(K0.to_sympy(a)) def from_ExpressionDomain(K1, a, K0): """Convert a ``EX`` object to ``dtype``. """ return a def get_ring(self): """Returns a ring associated with ``self``. """ return self # XXX: EX is not a ring but we don't have much choice here. def get_field(self): """Returns a field associated with ``self``. """ return self def is_positive(self, a): """Returns True if ``a`` is positive. """ return a.ex.as_coeff_mul()[0].is_positive def is_negative(self, a): """Returns True if ``a`` is negative. """ return a.ex.could_extract_minus_sign() def is_nonpositive(self, a): """Returns True if ``a`` is non-positive. """ return a.ex.as_coeff_mul()[0].is_nonpositive def is_nonnegative(self, a): """Returns True if ``a`` is non-negative. """ return a.ex.as_coeff_mul()[0].is_nonnegative def numer(self, a): """Returns numerator of ``a``. """ return a.numer() def denom(self, a): """Returns denominator of ``a``. """ return a.denom() def gcd(self, a, b): return self(1) def lcm(self, a, b): return a.lcm(b) EX = ExpressionDomain()
eaa55be19cdfabc02bc43ca0857c16e55bf0e126adb5d22dd07531e167270fc5
"""Implementation of :class:`FractionField` class. """ from sympy.polys.domains.field import Field from sympy.polys.domains.compositedomain import CompositeDomain from sympy.polys.domains.characteristiczero import CharacteristicZero from sympy.polys.polyclasses import DMF from sympy.polys.polyerrors import GeneratorsNeeded from sympy.polys.polyutils import dict_from_basic, basic_from_dict, _dict_reorder from sympy.utilities import public @public class FractionField(Field, CharacteristicZero, CompositeDomain): """A class for representing rational function fields. """ dtype = DMF is_FractionField = is_Frac = True has_assoc_Ring = True has_assoc_Field = True def __init__(self, dom, *gens): if not gens: raise GeneratorsNeeded("generators not specified") lev = len(gens) - 1 self.ngens = len(gens) self.zero = self.dtype.zero(lev, dom, ring=self) self.one = self.dtype.one(lev, dom, ring=self) self.domain = self.dom = dom self.symbols = self.gens = gens def new(self, element): return self.dtype(element, self.dom, len(self.gens) - 1, ring=self) def __str__(self): return str(self.dom) + '(' + ','.join(map(str, self.gens)) + ')' def __hash__(self): return hash((self.__class__.__name__, self.dtype, self.dom, self.gens)) def __eq__(self, other): """Returns ``True`` if two domains are equivalent. """ return isinstance(other, FractionField) and \ self.dtype == other.dtype and self.dom == other.dom and self.gens == other.gens def to_sympy(self, a): """Convert ``a`` to a SymPy object. """ return (basic_from_dict(a.numer().to_sympy_dict(), *self.gens) / basic_from_dict(a.denom().to_sympy_dict(), *self.gens)) def from_sympy(self, a): """Convert SymPy's expression to ``dtype``. """ p, q = a.as_numer_denom() num, _ = dict_from_basic(p, gens=self.gens) den, _ = dict_from_basic(q, gens=self.gens) for k, v in num.items(): num[k] = self.dom.from_sympy(v) for k, v in den.items(): den[k] = self.dom.from_sympy(v) return self((num, den)).cancel() def from_ZZ(K1, a, K0): """Convert a Python ``int`` object to ``dtype``. """ return K1(K1.dom.convert(a, K0)) def from_ZZ_python(K1, a, K0): """Convert a Python ``int`` object to ``dtype``. """ return K1(K1.dom.convert(a, K0)) def from_QQ_python(K1, a, K0): """Convert a Python ``Fraction`` object to ``dtype``. """ return K1(K1.dom.convert(a, K0)) def from_ZZ_gmpy(K1, a, K0): """Convert a GMPY ``mpz`` object to ``dtype``. """ return K1(K1.dom.convert(a, K0)) def from_QQ_gmpy(K1, a, K0): """Convert a GMPY ``mpq`` object to ``dtype``. """ return K1(K1.dom.convert(a, K0)) def from_RealField(K1, a, K0): """Convert a mpmath ``mpf`` object to ``dtype``. """ return K1(K1.dom.convert(a, K0)) def from_GlobalPolynomialRing(K1, a, K0): """Convert a ``DMF`` object to ``dtype``. """ if K1.gens == K0.gens: if K1.dom == K0.dom: return K1(a.rep) else: return K1(a.convert(K1.dom).rep) else: monoms, coeffs = _dict_reorder(a.to_dict(), K0.gens, K1.gens) if K1.dom != K0.dom: coeffs = [ K1.dom.convert(c, K0.dom) for c in coeffs ] return K1(dict(zip(monoms, coeffs))) def from_FractionField(K1, a, K0): """ Convert a fraction field element to another fraction field. Examples ======== >>> from sympy.polys.polyclasses import DMF >>> from sympy.polys.domains import ZZ, QQ >>> from sympy.abc import x >>> f = DMF(([ZZ(1), ZZ(2)], [ZZ(1), ZZ(1)]), ZZ) >>> QQx = QQ.old_frac_field(x) >>> ZZx = ZZ.old_frac_field(x) >>> QQx.from_FractionField(f, ZZx) (x + 2)/(x + 1) """ if K1.gens == K0.gens: if K1.dom == K0.dom: return a else: return K1((a.numer().convert(K1.dom).rep, a.denom().convert(K1.dom).rep)) elif set(K0.gens).issubset(K1.gens): nmonoms, ncoeffs = _dict_reorder( a.numer().to_dict(), K0.gens, K1.gens) dmonoms, dcoeffs = _dict_reorder( a.denom().to_dict(), K0.gens, K1.gens) if K1.dom != K0.dom: ncoeffs = [ K1.dom.convert(c, K0.dom) for c in ncoeffs ] dcoeffs = [ K1.dom.convert(c, K0.dom) for c in dcoeffs ] return K1((dict(zip(nmonoms, ncoeffs)), dict(zip(dmonoms, dcoeffs)))) def get_ring(self): """Returns a ring associated with ``self``. """ from sympy.polys.domains import PolynomialRing return PolynomialRing(self.dom, *self.gens) def poly_ring(self, *gens): """Returns a polynomial ring, i.e. `K[X]`. """ raise NotImplementedError('nested domains not allowed') def frac_field(self, *gens): """Returns a fraction field, i.e. `K(X)`. """ raise NotImplementedError('nested domains not allowed') def is_positive(self, a): """Returns True if ``a`` is positive. """ return self.dom.is_positive(a.numer().LC()) def is_negative(self, a): """Returns True if ``a`` is negative. """ return self.dom.is_negative(a.numer().LC()) def is_nonpositive(self, a): """Returns True if ``a`` is non-positive. """ return self.dom.is_nonpositive(a.numer().LC()) def is_nonnegative(self, a): """Returns True if ``a`` is non-negative. """ return self.dom.is_nonnegative(a.numer().LC()) def numer(self, a): """Returns numerator of ``a``. """ return a.numer() def denom(self, a): """Returns denominator of ``a``. """ return a.denom() def factorial(self, a): """Returns factorial of ``a``. """ return self.dtype(self.dom.factorial(a))
ec7a3ab7821c4384ab51e752b0947e07879b0d7237f01a7ce9b66a9d115d4f7b
"""Domains of Gaussian type.""" from sympy.core.numbers import I from sympy.polys.polyerrors import CoercionFailed from sympy.polys.domains.integerring import ZZ from sympy.polys.domains.rationalfield import QQ from sympy.polys.domains.algebraicfield import AlgebraicField from sympy.polys.domains.domain import Domain from sympy.polys.domains.domainelement import DomainElement from sympy.polys.domains.field import Field from sympy.polys.domains.ring import Ring class GaussianElement(DomainElement): """Base class for elements of Gaussian type domains.""" base = None # type: Domain _parent = None # type: Domain __slots__ = ('x', 'y') def __new__(cls, x, y=0): conv = cls.base.convert return cls.new(conv(x), conv(y)) @classmethod def new(cls, x, y): """Create a new GaussianElement of the same domain.""" obj = super().__new__(cls) obj.x = x obj.y = y return obj def parent(self): """The domain that this is an element of (ZZ_I or QQ_I)""" return self._parent def __hash__(self): return hash((self.x, self.y)) def __eq__(self, other): if isinstance(other, self.__class__): return self.x == other.x and self.y == other.y else: return NotImplemented def __lt__(self, other): if not isinstance(other, GaussianElement): return NotImplemented return [self.y, self.x] < [other.y, other.x] def __pos__(self): return self def __neg__(self): return self.new(-self.x, -self.y) def __repr__(self): return "%s(%s, %s)" % (self._parent.rep, self.x, self.y) def __str__(self): return str(self._parent.to_sympy(self)) @classmethod def _get_xy(cls, other): if not isinstance(other, cls): try: other = cls._parent.convert(other) except CoercionFailed: return None, None return other.x, other.y def __add__(self, other): x, y = self._get_xy(other) if x is not None: return self.new(self.x + x, self.y + y) else: return NotImplemented __radd__ = __add__ def __sub__(self, other): x, y = self._get_xy(other) if x is not None: return self.new(self.x - x, self.y - y) else: return NotImplemented def __rsub__(self, other): x, y = self._get_xy(other) if x is not None: return self.new(x - self.x, y - self.y) else: return NotImplemented def __mul__(self, other): x, y = self._get_xy(other) if x is not None: return self.new(self.x*x - self.y*y, self.x*y + self.y*x) else: return NotImplemented __rmul__ = __mul__ def __pow__(self, exp): if exp == 0: return self.new(1, 0) if exp < 0: self, exp = 1/self, -exp if exp == 1: return self pow2 = self prod = self if exp % 2 else self._parent.one exp //= 2 while exp: pow2 *= pow2 if exp % 2: prod *= pow2 exp //= 2 return prod def __bool__(self): return bool(self.x) or bool(self.y) def quadrant(self): """Return quadrant index 0-3. 0 is included in quadrant 0. """ if self.y > 0: return 0 if self.x > 0 else 1 elif self.y < 0: return 2 if self.x < 0 else 3 else: return 0 if self.x >= 0 else 2 def __rdivmod__(self, other): try: other = self._parent.convert(other) except CoercionFailed: return NotImplemented else: return other.__divmod__(self) def __rtruediv__(self, other): try: other = QQ_I.convert(other) except CoercionFailed: return NotImplemented else: return other.__truediv__(self) def __floordiv__(self, other): qr = self.__divmod__(other) return qr if qr is NotImplemented else qr[0] def __rfloordiv__(self, other): qr = self.__rdivmod__(other) return qr if qr is NotImplemented else qr[0] def __mod__(self, other): qr = self.__divmod__(other) return qr if qr is NotImplemented else qr[1] def __rmod__(self, other): qr = self.__rdivmod__(other) return qr if qr is NotImplemented else qr[1] class GaussianInteger(GaussianElement): """Gaussian integer: domain element for :ref:`ZZ_I` >>> from sympy import ZZ_I >>> z = ZZ_I(2, 3) >>> z (2 + 3*I) >>> type(z) <class 'sympy.polys.domains.gaussiandomains.GaussianInteger'> """ base = ZZ def __truediv__(self, other): """Return a Gaussian rational.""" return QQ_I.convert(self)/other def __divmod__(self, other): if not other: raise ZeroDivisionError('divmod({}, 0)'.format(self)) x, y = self._get_xy(other) if x is None: return NotImplemented # multiply self and other by x - I*y # self/other == (a + I*b)/c a, b = self.x*x + self.y*y, -self.x*y + self.y*x c = x*x + y*y # find integers qx and qy such that # |a - qx*c| <= c/2 and |b - qy*c| <= c/2 qx = (2*a + c) // (2*c) # -c <= 2*a - qx*2*c < c qy = (2*b + c) // (2*c) q = GaussianInteger(qx, qy) # |self/other - q| < 1 since # |a/c - qx|**2 + |b/c - qy|**2 <= 1/4 + 1/4 < 1 return q, self - q*other # |r| < |other| class GaussianRational(GaussianElement): """Gaussian rational: domain element for :ref:`QQ_I` >>> from sympy import QQ_I, QQ >>> z = QQ_I(QQ(2, 3), QQ(4, 5)) >>> z (2/3 + 4/5*I) >>> type(z) <class 'sympy.polys.domains.gaussiandomains.GaussianRational'> """ base = QQ def __truediv__(self, other): """Return a Gaussian rational.""" if not other: raise ZeroDivisionError('{} / 0'.format(self)) x, y = self._get_xy(other) if x is None: return NotImplemented c = x*x + y*y return GaussianRational((self.x*x + self.y*y)/c, (-self.x*y + self.y*x)/c) def __divmod__(self, other): try: other = self._parent.convert(other) except CoercionFailed: return NotImplemented if not other: raise ZeroDivisionError('{} % 0'.format(self)) else: return self/other, QQ_I.zero class GaussianDomain(): """Base class for Gaussian domains.""" dom = None # type: Domain is_Numerical = True is_Exact = True has_assoc_Ring = True has_assoc_Field = True def to_sympy(self, a): """Convert ``a`` to a SymPy object. """ conv = self.dom.to_sympy return conv(a.x) + I*conv(a.y) def from_sympy(self, a): """Convert a SymPy object to ``self.dtype``.""" r, b = a.as_coeff_Add() x = self.dom.from_sympy(r) # may raise CoercionFailed if not b: return self.new(x, 0) r, b = b.as_coeff_Mul() y = self.dom.from_sympy(r) if b is I: return self.new(x, y) else: raise CoercionFailed("{} is not Gaussian".format(a)) def inject(self, *gens): """Inject generators into this domain. """ return self.poly_ring(*gens) def canonical_unit(self, d): unit = self.units[-d.quadrant()] # - for inverse power return unit def is_negative(self, element): """Returns ``False`` for any ``GaussianElement``. """ return False def is_positive(self, element): """Returns ``False`` for any ``GaussianElement``. """ return False def is_nonnegative(self, element): """Returns ``False`` for any ``GaussianElement``. """ return False def is_nonpositive(self, element): """Returns ``False`` for any ``GaussianElement``. """ return False def from_ZZ_gmpy(K1, a, K0): """Convert a GMPY mpz to ``self.dtype``.""" return K1(a) def from_ZZ(K1, a, K0): """Convert a ZZ_python element to ``self.dtype``.""" return K1(a) def from_ZZ_python(K1, a, K0): """Convert a ZZ_python element to ``self.dtype``.""" return K1(a) def from_QQ(K1, a, K0): """Convert a GMPY mpq to ``self.dtype``.""" return K1(a) def from_QQ_gmpy(K1, a, K0): """Convert a GMPY mpq to ``self.dtype``.""" return K1(a) def from_QQ_python(K1, a, K0): """Convert a QQ_python element to ``self.dtype``.""" return K1(a) def from_AlgebraicField(K1, a, K0): """Convert an element from ZZ<I> or QQ<I> to ``self.dtype``.""" if K0.ext.args[0] == I: return K1.from_sympy(K0.to_sympy(a)) class GaussianIntegerRing(GaussianDomain, Ring): r"""Ring of Gaussian integers ``ZZ_I`` The :ref:`ZZ_I` domain represents the `Gaussian integers`_ `\mathbb{Z}[i]` as a :py:class:`~.Domain` in the domain system (see :ref:`polys-domainsintro`). By default a :py:class:`~.Poly` created from an expression with coefficients that are combinations of integers and ``I`` (`\sqrt{-1}`) will have the domain :ref:`ZZ_I`. >>> from sympy import Poly, Symbol, I >>> x = Symbol('x') >>> p = Poly(x**2 + I) >>> p Poly(x**2 + I, x, domain='ZZ_I') >>> p.domain ZZ_I The :ref:`ZZ_I` domain can be used to factorise polynomials that are reducible over the Gaussian integers. >>> from sympy import factor >>> factor(x**2 + 1) x**2 + 1 >>> factor(x**2 + 1, domain='ZZ_I') (x - I)*(x + I) The corresponding `field of fractions`_ is the domain of the Gaussian rationals :ref:`QQ_I`. Conversely :ref:`ZZ_I` is the `ring of integers`_ of :ref:`QQ_I`. >>> from sympy import ZZ_I, QQ_I >>> ZZ_I.get_field() QQ_I >>> QQ_I.get_ring() ZZ_I When using the domain directly :ref:`ZZ_I` can be used as a constructor. >>> ZZ_I(3, 4) (3 + 4*I) >>> ZZ_I(5) (5 + 0*I) The domain elements of :ref:`ZZ_I` are instances of :py:class:`~.GaussianInteger` which support the rings operations ``+,-,*,**``. >>> z1 = ZZ_I(5, 1) >>> z2 = ZZ_I(2, 3) >>> z1 (5 + 1*I) >>> z2 (2 + 3*I) >>> z1 + z2 (7 + 4*I) >>> z1 * z2 (7 + 17*I) >>> z1 ** 2 (24 + 10*I) Both floor (``//``) and modulo (``%``) division work with :py:class:`~.GaussianInteger` (see the :py:meth:`~.Domain.div` method). >>> z3, z4 = ZZ_I(5), ZZ_I(1, 3) >>> z3 // z4 # floor division (1 + -1*I) >>> z3 % z4 # modulo division (remainder) (1 + -2*I) >>> (z3//z4)*z4 + z3%z4 == z3 True True division (``/``) in :ref:`ZZ_I` gives an element of :ref:`QQ_I`. The :py:meth:`~.Domain.exquo` method can be used to divide in :ref:`ZZ_I` when exact division is possible. >>> z1 / z2 (1 + -1*I) >>> ZZ_I.exquo(z1, z2) (1 + -1*I) >>> z3 / z4 (1/2 + -3/2*I) >>> ZZ_I.exquo(z3, z4) Traceback (most recent call last): ... ExactQuotientFailed: (1 + 3*I) does not divide (5 + 0*I) in ZZ_I The :py:meth:`~.Domain.gcd` method can be used to compute the `gcd`_ of any two elements. >>> ZZ_I.gcd(ZZ_I(10), ZZ_I(2)) (2 + 0*I) >>> ZZ_I.gcd(ZZ_I(5), ZZ_I(2, 1)) (2 + 1*I) .. _Gaussian integers: https://en.wikipedia.org/wiki/Gaussian_integer .. _gcd: https://en.wikipedia.org/wiki/Greatest_common_divisor """ dom = ZZ dtype = GaussianInteger zero = dtype(ZZ(0), ZZ(0)) one = dtype(ZZ(1), ZZ(0)) imag_unit = dtype(ZZ(0), ZZ(1)) units = (one, imag_unit, -one, -imag_unit) # powers of i rep = 'ZZ_I' is_GaussianRing = True is_ZZ_I = True def __init__(self): # override Domain.__init__ """For constructing ZZ_I.""" def get_ring(self): """Returns a ring associated with ``self``. """ return self def get_field(self): """Returns a field associated with ``self``. """ return QQ_I def normalize(self, d, *args): """Return first quadrant element associated with ``d``. Also multiply the other arguments by the same power of i. """ unit = self.canonical_unit(d) d *= unit args = tuple(a*unit for a in args) return (d,) + args if args else d def gcd(self, a, b): """Greatest common divisor of a and b over ZZ_I.""" while b: a, b = b, a % b return self.normalize(a) def lcm(self, a, b): """Least common multiple of a and b over ZZ_I.""" return (a * b) // self.gcd(a, b) def from_GaussianIntegerRing(K1, a, K0): """Convert a ZZ_I element to ZZ_I.""" return a def from_GaussianRationalField(K1, a, K0): """Convert a QQ_I element to ZZ_I.""" return K1.new(ZZ.convert(a.x), ZZ.convert(a.y)) ZZ_I = GaussianInteger._parent = GaussianIntegerRing() class GaussianRationalField(GaussianDomain, Field): r"""Field of Gaussian rationals ``QQ_I`` The :ref:`QQ_I` domain represents the `Gaussian rationals`_ `\mathbb{Q}(i)` as a :py:class:`~.Domain` in the domain system (see :ref:`polys-domainsintro`). By default a :py:class:`~.Poly` created from an expression with coefficients that are combinations of rationals and ``I`` (`\sqrt{-1}`) will have the domain :ref:`QQ_I`. >>> from sympy import Poly, Symbol, I >>> x = Symbol('x') >>> p = Poly(x**2 + I/2) >>> p Poly(x**2 + I/2, x, domain='QQ_I') >>> p.domain QQ_I The polys option ``gaussian=True`` can be used to specify that the domain should be :ref:`QQ_I` even if the coefficients do not contain ``I`` or are all integers. >>> Poly(x**2) Poly(x**2, x, domain='ZZ') >>> Poly(x**2 + I) Poly(x**2 + I, x, domain='ZZ_I') >>> Poly(x**2/2) Poly(1/2*x**2, x, domain='QQ') >>> Poly(x**2, gaussian=True) Poly(x**2, x, domain='QQ_I') >>> Poly(x**2 + I, gaussian=True) Poly(x**2 + I, x, domain='QQ_I') >>> Poly(x**2/2, gaussian=True) Poly(1/2*x**2, x, domain='QQ_I') The :ref:`QQ_I` domain can be used to factorise polynomials that are reducible over the Gaussian rationals. >>> from sympy import factor, QQ_I >>> factor(x**2/4 + 1) (x**2 + 4)/4 >>> factor(x**2/4 + 1, domain='QQ_I') (x - 2*I)*(x + 2*I)/4 >>> factor(x**2/4 + 1, domain=QQ_I) (x - 2*I)*(x + 2*I)/4 It is also possible to specify the :ref:`QQ_I` domain explicitly with polys functions like :py:func:`~.apart`. >>> from sympy import apart >>> apart(1/(1 + x**2)) 1/(x**2 + 1) >>> apart(1/(1 + x**2), domain=QQ_I) I/(2*(x + I)) - I/(2*(x - I)) The corresponding `ring of integers`_ is the domain of the Gaussian integers :ref:`ZZ_I`. Conversely :ref:`QQ_I` is the `field of fractions`_ of :ref:`ZZ_I`. >>> from sympy import ZZ_I, QQ_I, QQ >>> ZZ_I.get_field() QQ_I >>> QQ_I.get_ring() ZZ_I When using the domain directly :ref:`QQ_I` can be used as a constructor. >>> QQ_I(3, 4) (3 + 4*I) >>> QQ_I(5) (5 + 0*I) >>> QQ_I(QQ(2, 3), QQ(4, 5)) (2/3 + 4/5*I) The domain elements of :ref:`QQ_I` are instances of :py:class:`~.GaussianRational` which support the field operations ``+,-,*,**,/``. >>> z1 = QQ_I(5, 1) >>> z2 = QQ_I(2, QQ(1, 2)) >>> z1 (5 + 1*I) >>> z2 (2 + 1/2*I) >>> z1 + z2 (7 + 3/2*I) >>> z1 * z2 (19/2 + 9/2*I) >>> z2 ** 2 (15/4 + 2*I) True division (``/``) in :ref:`QQ_I` gives an element of :ref:`QQ_I` and is always exact. >>> z1 / z2 (42/17 + -2/17*I) >>> QQ_I.exquo(z1, z2) (42/17 + -2/17*I) >>> z1 == (z1/z2)*z2 True Both floor (``//``) and modulo (``%``) division can be used with :py:class:`~.GaussianRational` (see :py:meth:`~.Domain.div`) but division is always exact so there is no remainder. >>> z1 // z2 (42/17 + -2/17*I) >>> z1 % z2 (0 + 0*I) >>> QQ_I.div(z1, z2) ((42/17 + -2/17*I), (0 + 0*I)) >>> (z1//z2)*z2 + z1%z2 == z1 True .. _Gaussian rationals: https://en.wikipedia.org/wiki/Gaussian_rational """ dom = QQ dtype = GaussianRational zero = dtype(QQ(0), QQ(0)) one = dtype(QQ(1), QQ(0)) imag_unit = dtype(QQ(0), QQ(1)) units = (one, imag_unit, -one, -imag_unit) # powers of i rep = 'QQ_I' is_GaussianField = True is_QQ_I = True def __init__(self): # override Domain.__init__ """For constructing QQ_I.""" def get_ring(self): """Returns a ring associated with ``self``. """ return ZZ_I def get_field(self): """Returns a field associated with ``self``. """ return self def as_AlgebraicField(self): """Get equivalent domain as an ``AlgebraicField``. """ return AlgebraicField(self.dom, I) def numer(self, a): """Get the numerator of ``a``.""" ZZ_I = self.get_ring() return ZZ_I.convert(a * self.denom(a)) def denom(self, a): """Get the denominator of ``a``.""" ZZ = self.dom.get_ring() QQ = self.dom ZZ_I = self.get_ring() denom_ZZ = ZZ.lcm(QQ.denom(a.x), QQ.denom(a.y)) return ZZ_I(denom_ZZ, ZZ.zero) def from_GaussianIntegerRing(K1, a, K0): """Convert a ZZ_I element to QQ_I.""" return K1.new(a.x, a.y) def from_GaussianRationalField(K1, a, K0): """Convert a QQ_I element to QQ_I.""" return a QQ_I = GaussianRational._parent = GaussianRationalField()
273257e0edc451052c470117bc6ce97dd1371882130e21daa5ea601fb761d57d
"""Test sparse polynomials. """ from functools import reduce from operator import add, mul from sympy.polys.rings import ring, xring, sring, PolyRing, PolyElement from sympy.polys.fields import field, FracField from sympy.polys.domains import ZZ, QQ, RR, FF, EX from sympy.polys.orderings import lex, grlex from sympy.polys.polyerrors import GeneratorsError, \ ExactQuotientFailed, MultivariatePolynomialError, CoercionFailed from sympy.testing.pytest import raises from sympy.core import Symbol, symbols from sympy import sqrt, pi, oo def test_PolyRing___init__(): x, y, z, t = map(Symbol, "xyzt") assert len(PolyRing("x,y,z", ZZ, lex).gens) == 3 assert len(PolyRing(x, ZZ, lex).gens) == 1 assert len(PolyRing(("x", "y", "z"), ZZ, lex).gens) == 3 assert len(PolyRing((x, y, z), ZZ, lex).gens) == 3 assert len(PolyRing("", ZZ, lex).gens) == 0 assert len(PolyRing([], ZZ, lex).gens) == 0 raises(GeneratorsError, lambda: PolyRing(0, ZZ, lex)) assert PolyRing("x", ZZ[t], lex).domain == ZZ[t] assert PolyRing("x", 'ZZ[t]', lex).domain == ZZ[t] assert PolyRing("x", PolyRing("t", ZZ, lex), lex).domain == ZZ[t] raises(GeneratorsError, lambda: PolyRing("x", PolyRing("x", ZZ, lex), lex)) _lex = Symbol("lex") assert PolyRing("x", ZZ, lex).order == lex assert PolyRing("x", ZZ, _lex).order == lex assert PolyRing("x", ZZ, 'lex').order == lex R1 = PolyRing("x,y", ZZ, lex) R2 = PolyRing("x,y", ZZ, lex) R3 = PolyRing("x,y,z", ZZ, lex) assert R1.x == R1.gens[0] assert R1.y == R1.gens[1] assert R1.x == R2.x assert R1.y == R2.y assert R1.x != R3.x assert R1.y != R3.y def test_PolyRing___hash__(): R, x, y, z = ring("x,y,z", QQ) assert hash(R) def test_PolyRing___eq__(): assert ring("x,y,z", QQ)[0] == ring("x,y,z", QQ)[0] assert ring("x,y,z", QQ)[0] is ring("x,y,z", QQ)[0] assert ring("x,y,z", QQ)[0] != ring("x,y,z", ZZ)[0] assert ring("x,y,z", QQ)[0] is not ring("x,y,z", ZZ)[0] assert ring("x,y,z", ZZ)[0] != ring("x,y,z", QQ)[0] assert ring("x,y,z", ZZ)[0] is not ring("x,y,z", QQ)[0] assert ring("x,y,z", QQ)[0] != ring("x,y", QQ)[0] assert ring("x,y,z", QQ)[0] is not ring("x,y", QQ)[0] assert ring("x,y", QQ)[0] != ring("x,y,z", QQ)[0] assert ring("x,y", QQ)[0] is not ring("x,y,z", QQ)[0] def test_PolyRing_ring_new(): R, x, y, z = ring("x,y,z", QQ) assert R.ring_new(7) == R(7) assert R.ring_new(7*x*y*z) == 7*x*y*z f = x**2 + 2*x*y + 3*x + 4*z**2 + 5*z + 6 assert R.ring_new([[[1]], [[2], [3]], [[4, 5, 6]]]) == f assert R.ring_new({(2, 0, 0): 1, (1, 1, 0): 2, (1, 0, 0): 3, (0, 0, 2): 4, (0, 0, 1): 5, (0, 0, 0): 6}) == f assert R.ring_new([((2, 0, 0), 1), ((1, 1, 0), 2), ((1, 0, 0), 3), ((0, 0, 2), 4), ((0, 0, 1), 5), ((0, 0, 0), 6)]) == f R, = ring("", QQ) assert R.ring_new([((), 7)]) == R(7) def test_PolyRing_drop(): R, x,y,z = ring("x,y,z", ZZ) assert R.drop(x) == PolyRing("y,z", ZZ, lex) assert R.drop(y) == PolyRing("x,z", ZZ, lex) assert R.drop(z) == PolyRing("x,y", ZZ, lex) assert R.drop(0) == PolyRing("y,z", ZZ, lex) assert R.drop(0).drop(0) == PolyRing("z", ZZ, lex) assert R.drop(0).drop(0).drop(0) == ZZ assert R.drop(1) == PolyRing("x,z", ZZ, lex) assert R.drop(2) == PolyRing("x,y", ZZ, lex) assert R.drop(2).drop(1) == PolyRing("x", ZZ, lex) assert R.drop(2).drop(1).drop(0) == ZZ raises(ValueError, lambda: R.drop(3)) raises(ValueError, lambda: R.drop(x).drop(y)) def test_PolyRing___getitem__(): R, x,y,z = ring("x,y,z", ZZ) assert R[0:] == PolyRing("x,y,z", ZZ, lex) assert R[1:] == PolyRing("y,z", ZZ, lex) assert R[2:] == PolyRing("z", ZZ, lex) assert R[3:] == ZZ def test_PolyRing_is_(): R = PolyRing("x", QQ, lex) assert R.is_univariate is True assert R.is_multivariate is False R = PolyRing("x,y,z", QQ, lex) assert R.is_univariate is False assert R.is_multivariate is True R = PolyRing("", QQ, lex) assert R.is_univariate is False assert R.is_multivariate is False def test_PolyRing_add(): R, x = ring("x", ZZ) F = [ x**2 + 2*i + 3 for i in range(4) ] assert R.add(F) == reduce(add, F) == 4*x**2 + 24 R, = ring("", ZZ) assert R.add([2, 5, 7]) == 14 def test_PolyRing_mul(): R, x = ring("x", ZZ) F = [ x**2 + 2*i + 3 for i in range(4) ] assert R.mul(F) == reduce(mul, F) == x**8 + 24*x**6 + 206*x**4 + 744*x**2 + 945 R, = ring("", ZZ) assert R.mul([2, 3, 5]) == 30 def test_sring(): x, y, z, t = symbols("x,y,z,t") R = PolyRing("x,y,z", ZZ, lex) assert sring(x + 2*y + 3*z) == (R, R.x + 2*R.y + 3*R.z) R = PolyRing("x,y,z", QQ, lex) assert sring(x + 2*y + z/3) == (R, R.x + 2*R.y + R.z/3) assert sring([x, 2*y, z/3]) == (R, [R.x, 2*R.y, R.z/3]) Rt = PolyRing("t", ZZ, lex) R = PolyRing("x,y,z", Rt, lex) assert sring(x + 2*t*y + 3*t**2*z, x, y, z) == (R, R.x + 2*Rt.t*R.y + 3*Rt.t**2*R.z) Rt = PolyRing("t", QQ, lex) R = PolyRing("x,y,z", Rt, lex) assert sring(x + t*y/2 + t**2*z/3, x, y, z) == (R, R.x + Rt.t*R.y/2 + Rt.t**2*R.z/3) Rt = FracField("t", ZZ, lex) R = PolyRing("x,y,z", Rt, lex) assert sring(x + 2*y/t + t**2*z/3, x, y, z) == (R, R.x + 2*R.y/Rt.t + Rt.t**2*R.z/3) r = sqrt(2) - sqrt(3) R, a = sring(r, extension=True) assert R.domain == QQ.algebraic_field(sqrt(2) + sqrt(3)) assert R.gens == () assert a == R.domain.from_sympy(r) def test_PolyElement___hash__(): R, x, y, z = ring("x,y,z", QQ) assert hash(x*y*z) def test_PolyElement___eq__(): R, x, y = ring("x,y", ZZ, lex) assert ((x*y + 5*x*y) == 6) == False assert ((x*y + 5*x*y) == 6*x*y) == True assert (6 == (x*y + 5*x*y)) == False assert (6*x*y == (x*y + 5*x*y)) == True assert ((x*y - x*y) == 0) == True assert (0 == (x*y - x*y)) == True assert ((x*y - x*y) == 1) == False assert (1 == (x*y - x*y)) == False assert ((x*y - x*y) == 1) == False assert (1 == (x*y - x*y)) == False assert ((x*y + 5*x*y) != 6) == True assert ((x*y + 5*x*y) != 6*x*y) == False assert (6 != (x*y + 5*x*y)) == True assert (6*x*y != (x*y + 5*x*y)) == False assert ((x*y - x*y) != 0) == False assert (0 != (x*y - x*y)) == False assert ((x*y - x*y) != 1) == True assert (1 != (x*y - x*y)) == True assert R.one == QQ(1, 1) == R.one assert R.one == 1 == R.one Rt, t = ring("t", ZZ) R, x, y = ring("x,y", Rt) assert (t**3*x/x == t**3) == True assert (t**3*x/x == t**4) == False def test_PolyElement__lt_le_gt_ge__(): R, x, y = ring("x,y", ZZ) assert R(1) < x < x**2 < x**3 assert R(1) <= x <= x**2 <= x**3 assert x**3 > x**2 > x > R(1) assert x**3 >= x**2 >= x >= R(1) def test_PolyElement_copy(): R, x, y, z = ring("x,y,z", ZZ) f = x*y + 3*z g = f.copy() assert f == g g[(1, 1, 1)] = 7 assert f != g def test_PolyElement_as_expr(): R, x, y, z = ring("x,y,z", ZZ) f = 3*x**2*y - x*y*z + 7*z**3 + 1 X, Y, Z = R.symbols g = 3*X**2*Y - X*Y*Z + 7*Z**3 + 1 assert f != g assert f.as_expr() == g X, Y, Z = symbols("x,y,z") g = 3*X**2*Y - X*Y*Z + 7*Z**3 + 1 assert f != g assert f.as_expr(X, Y, Z) == g raises(ValueError, lambda: f.as_expr(X)) R, = ring("", ZZ) R(3).as_expr() == 3 def test_PolyElement_from_expr(): x, y, z = symbols("x,y,z") R, X, Y, Z = ring((x, y, z), ZZ) f = R.from_expr(1) assert f == 1 and isinstance(f, R.dtype) f = R.from_expr(x) assert f == X and isinstance(f, R.dtype) f = R.from_expr(x*y*z) assert f == X*Y*Z and isinstance(f, R.dtype) f = R.from_expr(x*y*z + x*y + x) assert f == X*Y*Z + X*Y + X and isinstance(f, R.dtype) f = R.from_expr(x**3*y*z + x**2*y**7 + 1) assert f == X**3*Y*Z + X**2*Y**7 + 1 and isinstance(f, R.dtype) raises(ValueError, lambda: R.from_expr(1/x)) raises(ValueError, lambda: R.from_expr(2**x)) raises(ValueError, lambda: R.from_expr(7*x + sqrt(2))) R, = ring("", ZZ) f = R.from_expr(1) assert f == 1 and isinstance(f, R.dtype) def test_PolyElement_degree(): R, x,y,z = ring("x,y,z", ZZ) assert R(0).degree() is -oo assert R(1).degree() == 0 assert (x + 1).degree() == 1 assert (2*y**3 + z).degree() == 0 assert (x*y**3 + z).degree() == 1 assert (x**5*y**3 + z).degree() == 5 assert R(0).degree(x) is -oo assert R(1).degree(x) == 0 assert (x + 1).degree(x) == 1 assert (2*y**3 + z).degree(x) == 0 assert (x*y**3 + z).degree(x) == 1 assert (7*x**5*y**3 + z).degree(x) == 5 assert R(0).degree(y) is -oo assert R(1).degree(y) == 0 assert (x + 1).degree(y) == 0 assert (2*y**3 + z).degree(y) == 3 assert (x*y**3 + z).degree(y) == 3 assert (7*x**5*y**3 + z).degree(y) == 3 assert R(0).degree(z) is -oo assert R(1).degree(z) == 0 assert (x + 1).degree(z) == 0 assert (2*y**3 + z).degree(z) == 1 assert (x*y**3 + z).degree(z) == 1 assert (7*x**5*y**3 + z).degree(z) == 1 R, = ring("", ZZ) assert R(0).degree() is -oo assert R(1).degree() == 0 def test_PolyElement_tail_degree(): R, x,y,z = ring("x,y,z", ZZ) assert R(0).tail_degree() is -oo assert R(1).tail_degree() == 0 assert (x + 1).tail_degree() == 0 assert (2*y**3 + x**3*z).tail_degree() == 0 assert (x*y**3 + x**3*z).tail_degree() == 1 assert (x**5*y**3 + x**3*z).tail_degree() == 3 assert R(0).tail_degree(x) is -oo assert R(1).tail_degree(x) == 0 assert (x + 1).tail_degree(x) == 0 assert (2*y**3 + x**3*z).tail_degree(x) == 0 assert (x*y**3 + x**3*z).tail_degree(x) == 1 assert (7*x**5*y**3 + x**3*z).tail_degree(x) == 3 assert R(0).tail_degree(y) is -oo assert R(1).tail_degree(y) == 0 assert (x + 1).tail_degree(y) == 0 assert (2*y**3 + x**3*z).tail_degree(y) == 0 assert (x*y**3 + x**3*z).tail_degree(y) == 0 assert (7*x**5*y**3 + x**3*z).tail_degree(y) == 0 assert R(0).tail_degree(z) is -oo assert R(1).tail_degree(z) == 0 assert (x + 1).tail_degree(z) == 0 assert (2*y**3 + x**3*z).tail_degree(z) == 0 assert (x*y**3 + x**3*z).tail_degree(z) == 0 assert (7*x**5*y**3 + x**3*z).tail_degree(z) == 0 R, = ring("", ZZ) assert R(0).tail_degree() is -oo assert R(1).tail_degree() == 0 def test_PolyElement_degrees(): R, x,y,z = ring("x,y,z", ZZ) assert R(0).degrees() == (-oo, -oo, -oo) assert R(1).degrees() == (0, 0, 0) assert (x**2*y + x**3*z**2).degrees() == (3, 1, 2) def test_PolyElement_tail_degrees(): R, x,y,z = ring("x,y,z", ZZ) assert R(0).tail_degrees() == (-oo, -oo, -oo) assert R(1).tail_degrees() == (0, 0, 0) assert (x**2*y + x**3*z**2).tail_degrees() == (2, 0, 0) def test_PolyElement_coeff(): R, x, y, z = ring("x,y,z", ZZ, lex) f = 3*x**2*y - x*y*z + 7*z**3 + 23 assert f.coeff(1) == 23 raises(ValueError, lambda: f.coeff(3)) assert f.coeff(x) == 0 assert f.coeff(y) == 0 assert f.coeff(z) == 0 assert f.coeff(x**2*y) == 3 assert f.coeff(x*y*z) == -1 assert f.coeff(z**3) == 7 raises(ValueError, lambda: f.coeff(3*x**2*y)) raises(ValueError, lambda: f.coeff(-x*y*z)) raises(ValueError, lambda: f.coeff(7*z**3)) R, = ring("", ZZ) R(3).coeff(1) == 3 def test_PolyElement_LC(): R, x, y = ring("x,y", QQ, lex) assert R(0).LC == QQ(0) assert (QQ(1,2)*x).LC == QQ(1, 2) assert (QQ(1,4)*x*y + QQ(1,2)*x).LC == QQ(1, 4) def test_PolyElement_LM(): R, x, y = ring("x,y", QQ, lex) assert R(0).LM == (0, 0) assert (QQ(1,2)*x).LM == (1, 0) assert (QQ(1,4)*x*y + QQ(1,2)*x).LM == (1, 1) def test_PolyElement_LT(): R, x, y = ring("x,y", QQ, lex) assert R(0).LT == ((0, 0), QQ(0)) assert (QQ(1,2)*x).LT == ((1, 0), QQ(1, 2)) assert (QQ(1,4)*x*y + QQ(1,2)*x).LT == ((1, 1), QQ(1, 4)) R, = ring("", ZZ) assert R(0).LT == ((), 0) assert R(1).LT == ((), 1) def test_PolyElement_leading_monom(): R, x, y = ring("x,y", QQ, lex) assert R(0).leading_monom() == 0 assert (QQ(1,2)*x).leading_monom() == x assert (QQ(1,4)*x*y + QQ(1,2)*x).leading_monom() == x*y def test_PolyElement_leading_term(): R, x, y = ring("x,y", QQ, lex) assert R(0).leading_term() == 0 assert (QQ(1,2)*x).leading_term() == QQ(1,2)*x assert (QQ(1,4)*x*y + QQ(1,2)*x).leading_term() == QQ(1,4)*x*y def test_PolyElement_terms(): R, x,y,z = ring("x,y,z", QQ) terms = (x**2/3 + y**3/4 + z**4/5).terms() assert terms == [((2,0,0), QQ(1,3)), ((0,3,0), QQ(1,4)), ((0,0,4), QQ(1,5))] R, x,y = ring("x,y", ZZ, lex) f = x*y**7 + 2*x**2*y**3 assert f.terms() == f.terms(lex) == f.terms('lex') == [((2, 3), 2), ((1, 7), 1)] assert f.terms(grlex) == f.terms('grlex') == [((1, 7), 1), ((2, 3), 2)] R, x,y = ring("x,y", ZZ, grlex) f = x*y**7 + 2*x**2*y**3 assert f.terms() == f.terms(grlex) == f.terms('grlex') == [((1, 7), 1), ((2, 3), 2)] assert f.terms(lex) == f.terms('lex') == [((2, 3), 2), ((1, 7), 1)] R, = ring("", ZZ) assert R(3).terms() == [((), 3)] def test_PolyElement_monoms(): R, x,y,z = ring("x,y,z", QQ) monoms = (x**2/3 + y**3/4 + z**4/5).monoms() assert monoms == [(2,0,0), (0,3,0), (0,0,4)] R, x,y = ring("x,y", ZZ, lex) f = x*y**7 + 2*x**2*y**3 assert f.monoms() == f.monoms(lex) == f.monoms('lex') == [(2, 3), (1, 7)] assert f.monoms(grlex) == f.monoms('grlex') == [(1, 7), (2, 3)] R, x,y = ring("x,y", ZZ, grlex) f = x*y**7 + 2*x**2*y**3 assert f.monoms() == f.monoms(grlex) == f.monoms('grlex') == [(1, 7), (2, 3)] assert f.monoms(lex) == f.monoms('lex') == [(2, 3), (1, 7)] def test_PolyElement_coeffs(): R, x,y,z = ring("x,y,z", QQ) coeffs = (x**2/3 + y**3/4 + z**4/5).coeffs() assert coeffs == [QQ(1,3), QQ(1,4), QQ(1,5)] R, x,y = ring("x,y", ZZ, lex) f = x*y**7 + 2*x**2*y**3 assert f.coeffs() == f.coeffs(lex) == f.coeffs('lex') == [2, 1] assert f.coeffs(grlex) == f.coeffs('grlex') == [1, 2] R, x,y = ring("x,y", ZZ, grlex) f = x*y**7 + 2*x**2*y**3 assert f.coeffs() == f.coeffs(grlex) == f.coeffs('grlex') == [1, 2] assert f.coeffs(lex) == f.coeffs('lex') == [2, 1] def test_PolyElement___add__(): Rt, t = ring("t", ZZ) Ruv, u,v = ring("u,v", ZZ) Rxyz, x,y,z = ring("x,y,z", Ruv) assert dict(x + 3*y) == {(1, 0, 0): 1, (0, 1, 0): 3} assert dict(u + x) == dict(x + u) == {(1, 0, 0): 1, (0, 0, 0): u} assert dict(u + x*y) == dict(x*y + u) == {(1, 1, 0): 1, (0, 0, 0): u} assert dict(u + x*y + z) == dict(x*y + z + u) == {(1, 1, 0): 1, (0, 0, 1): 1, (0, 0, 0): u} assert dict(u*x + x) == dict(x + u*x) == {(1, 0, 0): u + 1} assert dict(u*x + x*y) == dict(x*y + u*x) == {(1, 1, 0): 1, (1, 0, 0): u} assert dict(u*x + x*y + z) == dict(x*y + z + u*x) == {(1, 1, 0): 1, (0, 0, 1): 1, (1, 0, 0): u} raises(TypeError, lambda: t + x) raises(TypeError, lambda: x + t) raises(TypeError, lambda: t + u) raises(TypeError, lambda: u + t) Fuv, u,v = field("u,v", ZZ) Rxyz, x,y,z = ring("x,y,z", Fuv) assert dict(u + x) == dict(x + u) == {(1, 0, 0): 1, (0, 0, 0): u} Rxyz, x,y,z = ring("x,y,z", EX) assert dict(EX(pi) + x*y*z) == dict(x*y*z + EX(pi)) == {(1, 1, 1): EX(1), (0, 0, 0): EX(pi)} def test_PolyElement___sub__(): Rt, t = ring("t", ZZ) Ruv, u,v = ring("u,v", ZZ) Rxyz, x,y,z = ring("x,y,z", Ruv) assert dict(x - 3*y) == {(1, 0, 0): 1, (0, 1, 0): -3} assert dict(-u + x) == dict(x - u) == {(1, 0, 0): 1, (0, 0, 0): -u} assert dict(-u + x*y) == dict(x*y - u) == {(1, 1, 0): 1, (0, 0, 0): -u} assert dict(-u + x*y + z) == dict(x*y + z - u) == {(1, 1, 0): 1, (0, 0, 1): 1, (0, 0, 0): -u} assert dict(-u*x + x) == dict(x - u*x) == {(1, 0, 0): -u + 1} assert dict(-u*x + x*y) == dict(x*y - u*x) == {(1, 1, 0): 1, (1, 0, 0): -u} assert dict(-u*x + x*y + z) == dict(x*y + z - u*x) == {(1, 1, 0): 1, (0, 0, 1): 1, (1, 0, 0): -u} raises(TypeError, lambda: t - x) raises(TypeError, lambda: x - t) raises(TypeError, lambda: t - u) raises(TypeError, lambda: u - t) Fuv, u,v = field("u,v", ZZ) Rxyz, x,y,z = ring("x,y,z", Fuv) assert dict(-u + x) == dict(x - u) == {(1, 0, 0): 1, (0, 0, 0): -u} Rxyz, x,y,z = ring("x,y,z", EX) assert dict(-EX(pi) + x*y*z) == dict(x*y*z - EX(pi)) == {(1, 1, 1): EX(1), (0, 0, 0): -EX(pi)} def test_PolyElement___mul__(): Rt, t = ring("t", ZZ) Ruv, u,v = ring("u,v", ZZ) Rxyz, x,y,z = ring("x,y,z", Ruv) assert dict(u*x) == dict(x*u) == {(1, 0, 0): u} assert dict(2*u*x + z) == dict(x*2*u + z) == {(1, 0, 0): 2*u, (0, 0, 1): 1} assert dict(u*2*x + z) == dict(2*x*u + z) == {(1, 0, 0): 2*u, (0, 0, 1): 1} assert dict(2*u*x + z) == dict(x*2*u + z) == {(1, 0, 0): 2*u, (0, 0, 1): 1} assert dict(u*x*2 + z) == dict(x*u*2 + z) == {(1, 0, 0): 2*u, (0, 0, 1): 1} assert dict(2*u*x*y + z) == dict(x*y*2*u + z) == {(1, 1, 0): 2*u, (0, 0, 1): 1} assert dict(u*2*x*y + z) == dict(2*x*y*u + z) == {(1, 1, 0): 2*u, (0, 0, 1): 1} assert dict(2*u*x*y + z) == dict(x*y*2*u + z) == {(1, 1, 0): 2*u, (0, 0, 1): 1} assert dict(u*x*y*2 + z) == dict(x*y*u*2 + z) == {(1, 1, 0): 2*u, (0, 0, 1): 1} assert dict(2*u*y*x + z) == dict(y*x*2*u + z) == {(1, 1, 0): 2*u, (0, 0, 1): 1} assert dict(u*2*y*x + z) == dict(2*y*x*u + z) == {(1, 1, 0): 2*u, (0, 0, 1): 1} assert dict(2*u*y*x + z) == dict(y*x*2*u + z) == {(1, 1, 0): 2*u, (0, 0, 1): 1} assert dict(u*y*x*2 + z) == dict(y*x*u*2 + z) == {(1, 1, 0): 2*u, (0, 0, 1): 1} assert dict(3*u*(x + y) + z) == dict((x + y)*3*u + z) == {(1, 0, 0): 3*u, (0, 1, 0): 3*u, (0, 0, 1): 1} raises(TypeError, lambda: t*x + z) raises(TypeError, lambda: x*t + z) raises(TypeError, lambda: t*u + z) raises(TypeError, lambda: u*t + z) Fuv, u,v = field("u,v", ZZ) Rxyz, x,y,z = ring("x,y,z", Fuv) assert dict(u*x) == dict(x*u) == {(1, 0, 0): u} Rxyz, x,y,z = ring("x,y,z", EX) assert dict(EX(pi)*x*y*z) == dict(x*y*z*EX(pi)) == {(1, 1, 1): EX(pi)} def test_PolyElement___truediv__(): R, x,y,z = ring("x,y,z", ZZ) assert (2*x**2 - 4)/2 == x**2 - 2 assert (2*x**2 - 3)/2 == x**2 assert (x**2 - 1).quo(x) == x assert (x**2 - x).quo(x) == x - 1 assert (x**2 - 1)/x == x - x**(-1) assert (x**2 - x)/x == x - 1 assert (x**2 - 1)/(2*x) == x/2 - x**(-1)/2 assert (x**2 - 1).quo(2*x) == 0 assert (x**2 - x)/(x - 1) == (x**2 - x).quo(x - 1) == x R, x,y,z = ring("x,y,z", ZZ) assert len((x**2/3 + y**3/4 + z**4/5).terms()) == 0 R, x,y,z = ring("x,y,z", QQ) assert len((x**2/3 + y**3/4 + z**4/5).terms()) == 3 Rt, t = ring("t", ZZ) Ruv, u,v = ring("u,v", ZZ) Rxyz, x,y,z = ring("x,y,z", Ruv) assert dict((u**2*x + u)/u) == {(1, 0, 0): u, (0, 0, 0): 1} raises(TypeError, lambda: u/(u**2*x + u)) raises(TypeError, lambda: t/x) raises(TypeError, lambda: x/t) raises(TypeError, lambda: t/u) raises(TypeError, lambda: u/t) R, x = ring("x", ZZ) f, g = x**2 + 2*x + 3, R(0) raises(ZeroDivisionError, lambda: f.div(g)) raises(ZeroDivisionError, lambda: divmod(f, g)) raises(ZeroDivisionError, lambda: f.rem(g)) raises(ZeroDivisionError, lambda: f % g) raises(ZeroDivisionError, lambda: f.quo(g)) raises(ZeroDivisionError, lambda: f / g) raises(ZeroDivisionError, lambda: f.exquo(g)) R, x, y = ring("x,y", ZZ) f, g = x*y + 2*x + 3, R(0) raises(ZeroDivisionError, lambda: f.div(g)) raises(ZeroDivisionError, lambda: divmod(f, g)) raises(ZeroDivisionError, lambda: f.rem(g)) raises(ZeroDivisionError, lambda: f % g) raises(ZeroDivisionError, lambda: f.quo(g)) raises(ZeroDivisionError, lambda: f / g) raises(ZeroDivisionError, lambda: f.exquo(g)) R, x = ring("x", ZZ) f, g = x**2 + 1, 2*x - 4 q, r = R(0), x**2 + 1 assert f.div(g) == divmod(f, g) == (q, r) assert f.rem(g) == f % g == r assert f.quo(g) == f / g == q raises(ExactQuotientFailed, lambda: f.exquo(g)) f, g = 3*x**3 + x**2 + x + 5, 5*x**2 - 3*x + 1 q, r = R(0), f assert f.div(g) == divmod(f, g) == (q, r) assert f.rem(g) == f % g == r assert f.quo(g) == f / g == q raises(ExactQuotientFailed, lambda: f.exquo(g)) f, g = 5*x**4 + 4*x**3 + 3*x**2 + 2*x + 1, x**2 + 2*x + 3 q, r = 5*x**2 - 6*x, 20*x + 1 assert f.div(g) == divmod(f, g) == (q, r) assert f.rem(g) == f % g == r assert f.quo(g) == f / g == q raises(ExactQuotientFailed, lambda: f.exquo(g)) f, g = 5*x**5 + 4*x**4 + 3*x**3 + 2*x**2 + x, x**4 + 2*x**3 + 9 q, r = 5*x - 6, 15*x**3 + 2*x**2 - 44*x + 54 assert f.div(g) == divmod(f, g) == (q, r) assert f.rem(g) == f % g == r assert f.quo(g) == f / g == q raises(ExactQuotientFailed, lambda: f.exquo(g)) R, x = ring("x", QQ) f, g = x**2 + 1, 2*x - 4 q, r = x/2 + 1, R(5) assert f.div(g) == divmod(f, g) == (q, r) assert f.rem(g) == f % g == r assert f.quo(g) == f / g == q raises(ExactQuotientFailed, lambda: f.exquo(g)) f, g = 3*x**3 + x**2 + x + 5, 5*x**2 - 3*x + 1 q, r = QQ(3, 5)*x + QQ(14, 25), QQ(52, 25)*x + QQ(111, 25) assert f.div(g) == divmod(f, g) == (q, r) assert f.rem(g) == f % g == r assert f.quo(g) == f / g == q raises(ExactQuotientFailed, lambda: f.exquo(g)) R, x,y = ring("x,y", ZZ) f, g = x**2 - y**2, x - y q, r = x + y, R(0) assert f.div(g) == divmod(f, g) == (q, r) assert f.rem(g) == f % g == r assert f.quo(g) == f / g == q assert f.exquo(g) == q f, g = x**2 + y**2, x - y q, r = x + y, 2*y**2 assert f.div(g) == divmod(f, g) == (q, r) assert f.rem(g) == f % g == r assert f.quo(g) == f / g == q raises(ExactQuotientFailed, lambda: f.exquo(g)) f, g = x**2 + y**2, -x + y q, r = -x - y, 2*y**2 assert f.div(g) == divmod(f, g) == (q, r) assert f.rem(g) == f % g == r assert f.quo(g) == f / g == q raises(ExactQuotientFailed, lambda: f.exquo(g)) f, g = x**2 + y**2, 2*x - 2*y q, r = R(0), f assert f.div(g) == divmod(f, g) == (q, r) assert f.rem(g) == f % g == r assert f.quo(g) == f / g == q raises(ExactQuotientFailed, lambda: f.exquo(g)) R, x,y = ring("x,y", QQ) f, g = x**2 - y**2, x - y q, r = x + y, R(0) assert f.div(g) == divmod(f, g) == (q, r) assert f.rem(g) == f % g == r assert f.quo(g) == f / g == q assert f.exquo(g) == q f, g = x**2 + y**2, x - y q, r = x + y, 2*y**2 assert f.div(g) == divmod(f, g) == (q, r) assert f.rem(g) == f % g == r assert f.quo(g) == f / g == q raises(ExactQuotientFailed, lambda: f.exquo(g)) f, g = x**2 + y**2, -x + y q, r = -x - y, 2*y**2 assert f.div(g) == divmod(f, g) == (q, r) assert f.rem(g) == f % g == r assert f.quo(g) == f / g == q raises(ExactQuotientFailed, lambda: f.exquo(g)) f, g = x**2 + y**2, 2*x - 2*y q, r = x/2 + y/2, 2*y**2 assert f.div(g) == divmod(f, g) == (q, r) assert f.rem(g) == f % g == r assert f.quo(g) == f / g == q raises(ExactQuotientFailed, lambda: f.exquo(g)) def test_PolyElement___pow__(): R, x = ring("x", ZZ, grlex) f = 2*x + 3 assert f**0 == 1 assert f**1 == f raises(ValueError, lambda: f**(-1)) assert x**(-1) == x**(-1) assert f**2 == f._pow_generic(2) == f._pow_multinomial(2) == 4*x**2 + 12*x + 9 assert f**3 == f._pow_generic(3) == f._pow_multinomial(3) == 8*x**3 + 36*x**2 + 54*x + 27 assert f**4 == f._pow_generic(4) == f._pow_multinomial(4) == 16*x**4 + 96*x**3 + 216*x**2 + 216*x + 81 assert f**5 == f._pow_generic(5) == f._pow_multinomial(5) == 32*x**5 + 240*x**4 + 720*x**3 + 1080*x**2 + 810*x + 243 R, x,y,z = ring("x,y,z", ZZ, grlex) f = x**3*y - 2*x*y**2 - 3*z + 1 g = x**6*y**2 - 4*x**4*y**3 - 6*x**3*y*z + 2*x**3*y + 4*x**2*y**4 + 12*x*y**2*z - 4*x*y**2 + 9*z**2 - 6*z + 1 assert f**2 == f._pow_generic(2) == f._pow_multinomial(2) == g R, t = ring("t", ZZ) f = -11200*t**4 - 2604*t**2 + 49 g = 15735193600000000*t**16 + 14633730048000000*t**14 + 4828147466240000*t**12 \ + 598976863027200*t**10 + 3130812416256*t**8 - 2620523775744*t**6 \ + 92413760096*t**4 - 1225431984*t**2 + 5764801 assert f**4 == f._pow_generic(4) == f._pow_multinomial(4) == g def test_PolyElement_div(): R, x = ring("x", ZZ, grlex) f = x**3 - 12*x**2 - 42 g = x - 3 q = x**2 - 9*x - 27 r = -123 assert f.div([g]) == ([q], r) R, x = ring("x", ZZ, grlex) f = x**2 + 2*x + 2 assert f.div([R(1)]) == ([f], 0) R, x = ring("x", QQ, grlex) f = x**2 + 2*x + 2 assert f.div([R(2)]) == ([QQ(1,2)*x**2 + x + 1], 0) R, x,y = ring("x,y", ZZ, grlex) f = 4*x**2*y - 2*x*y + 4*x - 2*y + 8 assert f.div([R(2)]) == ([2*x**2*y - x*y + 2*x - y + 4], 0) assert f.div([2*y]) == ([2*x**2 - x - 1], 4*x + 8) f = x - 1 g = y - 1 assert f.div([g]) == ([0], f) f = x*y**2 + 1 G = [x*y + 1, y + 1] Q = [y, -1] r = 2 assert f.div(G) == (Q, r) f = x**2*y + x*y**2 + y**2 G = [x*y - 1, y**2 - 1] Q = [x + y, 1] r = x + y + 1 assert f.div(G) == (Q, r) G = [y**2 - 1, x*y - 1] Q = [x + 1, x] r = 2*x + 1 assert f.div(G) == (Q, r) R, = ring("", ZZ) assert R(3).div(R(2)) == (0, 3) R, = ring("", QQ) assert R(3).div(R(2)) == (QQ(3, 2), 0) def test_PolyElement_rem(): R, x = ring("x", ZZ, grlex) f = x**3 - 12*x**2 - 42 g = x - 3 r = -123 assert f.rem([g]) == f.div([g])[1] == r R, x,y = ring("x,y", ZZ, grlex) f = 4*x**2*y - 2*x*y + 4*x - 2*y + 8 assert f.rem([R(2)]) == f.div([R(2)])[1] == 0 assert f.rem([2*y]) == f.div([2*y])[1] == 4*x + 8 f = x - 1 g = y - 1 assert f.rem([g]) == f.div([g])[1] == f f = x*y**2 + 1 G = [x*y + 1, y + 1] r = 2 assert f.rem(G) == f.div(G)[1] == r f = x**2*y + x*y**2 + y**2 G = [x*y - 1, y**2 - 1] r = x + y + 1 assert f.rem(G) == f.div(G)[1] == r G = [y**2 - 1, x*y - 1] r = 2*x + 1 assert f.rem(G) == f.div(G)[1] == r def test_PolyElement_deflate(): R, x = ring("x", ZZ) assert (2*x**2).deflate(x**4 + 4*x**2 + 1) == ((2,), [2*x, x**2 + 4*x + 1]) R, x,y = ring("x,y", ZZ) assert R(0).deflate(R(0)) == ((1, 1), [0, 0]) assert R(1).deflate(R(0)) == ((1, 1), [1, 0]) assert R(1).deflate(R(2)) == ((1, 1), [1, 2]) assert R(1).deflate(2*y) == ((1, 1), [1, 2*y]) assert (2*y).deflate(2*y) == ((1, 1), [2*y, 2*y]) assert R(2).deflate(2*y**2) == ((1, 2), [2, 2*y]) assert (2*y**2).deflate(2*y**2) == ((1, 2), [2*y, 2*y]) f = x**4*y**2 + x**2*y + 1 g = x**2*y**3 + x**2*y + 1 assert f.deflate(g) == ((2, 1), [x**2*y**2 + x*y + 1, x*y**3 + x*y + 1]) def test_PolyElement_clear_denoms(): R, x,y = ring("x,y", QQ) assert R(1).clear_denoms() == (ZZ(1), 1) assert R(7).clear_denoms() == (ZZ(1), 7) assert R(QQ(7,3)).clear_denoms() == (3, 7) assert R(QQ(7,3)).clear_denoms() == (3, 7) assert (3*x**2 + x).clear_denoms() == (1, 3*x**2 + x) assert (x**2 + QQ(1,2)*x).clear_denoms() == (2, 2*x**2 + x) rQQ, x,t = ring("x,t", QQ, lex) rZZ, X,T = ring("x,t", ZZ, lex) F = [x - QQ(17824537287975195925064602467992950991718052713078834557692023531499318507213727406844943097,413954288007559433755329699713866804710749652268151059918115348815925474842910720000)*t**7 - QQ(4882321164854282623427463828745855894130208215961904469205260756604820743234704900167747753,12936071500236232304854053116058337647210926633379720622441104650497671088840960000)*t**6 - QQ(36398103304520066098365558157422127347455927422509913596393052633155821154626830576085097433,25872143000472464609708106232116675294421853266759441244882209300995342177681920000)*t**5 - QQ(168108082231614049052707339295479262031324376786405372698857619250210703675982492356828810819,58212321751063045371843239022262519412449169850208742800984970927239519899784320000)*t**4 - QQ(5694176899498574510667890423110567593477487855183144378347226247962949388653159751849449037,1617008937529529038106756639507292205901365829172465077805138081312208886105120000)*t**3 - QQ(154482622347268833757819824809033388503591365487934245386958884099214649755244381307907779,60637835157357338929003373981523457721301218593967440417692678049207833228942000)*t**2 - QQ(2452813096069528207645703151222478123259511586701148682951852876484544822947007791153163,2425513406294293557160134959260938308852048743758697616707707121968313329157680)*t - QQ(34305265428126440542854669008203683099323146152358231964773310260498715579162112959703,202126117191191129763344579938411525737670728646558134725642260164026110763140), t**8 + QQ(693749860237914515552,67859264524169150569)*t**7 + QQ(27761407182086143225024,610733380717522355121)*t**6 + QQ(7785127652157884044288,67859264524169150569)*t**5 + QQ(36567075214771261409792,203577793572507451707)*t**4 + QQ(36336335165196147384320,203577793572507451707)*t**3 + QQ(7452455676042754048000,67859264524169150569)*t**2 + QQ(2593331082514399232000,67859264524169150569)*t + QQ(390399197427343360000,67859264524169150569)] G = [3725588592068034903797967297424801242396746870413359539263038139343329273586196480000*X - 160420835591776763325581422211936558925462474417709511019228211783493866564923546661604487873*T**7 - 1406108495478033395547109582678806497509499966197028487131115097902188374051595011248311352864*T**6 - 5241326875850889518164640374668786338033653548841427557880599579174438246266263602956254030352*T**5 - 10758917262823299139373269714910672770004760114329943852726887632013485035262879510837043892416*T**4 - 13119383576444715672578819534846747735372132018341964647712009275306635391456880068261130581248*T**3 - 9491412317016197146080450036267011389660653495578680036574753839055748080962214787557853941760*T**2 - 3767520915562795326943800040277726397326609797172964377014046018280260848046603967211258368000*T - 632314652371226552085897259159210286886724229880266931574701654721512325555116066073245696000, 610733380717522355121*T**8 + 6243748742141230639968*T**7 + 27761407182086143225024*T**6 + 70066148869420956398592*T**5 + 109701225644313784229376*T**4 + 109009005495588442152960*T**3 + 67072101084384786432000*T**2 + 23339979742629593088000*T + 3513592776846090240000] assert [ f.clear_denoms()[1].set_ring(rZZ) for f in F ] == G def test_PolyElement_cofactors(): R, x, y = ring("x,y", ZZ) f, g = R(0), R(0) assert f.cofactors(g) == (0, 0, 0) f, g = R(2), R(0) assert f.cofactors(g) == (2, 1, 0) f, g = R(-2), R(0) assert f.cofactors(g) == (2, -1, 0) f, g = R(0), R(-2) assert f.cofactors(g) == (2, 0, -1) f, g = R(0), 2*x + 4 assert f.cofactors(g) == (2*x + 4, 0, 1) f, g = 2*x + 4, R(0) assert f.cofactors(g) == (2*x + 4, 1, 0) f, g = R(2), R(2) assert f.cofactors(g) == (2, 1, 1) f, g = R(-2), R(2) assert f.cofactors(g) == (2, -1, 1) f, g = R(2), R(-2) assert f.cofactors(g) == (2, 1, -1) f, g = R(-2), R(-2) assert f.cofactors(g) == (2, -1, -1) f, g = x**2 + 2*x + 1, R(1) assert f.cofactors(g) == (1, x**2 + 2*x + 1, 1) f, g = x**2 + 2*x + 1, R(2) assert f.cofactors(g) == (1, x**2 + 2*x + 1, 2) f, g = 2*x**2 + 4*x + 2, R(2) assert f.cofactors(g) == (2, x**2 + 2*x + 1, 1) f, g = R(2), 2*x**2 + 4*x + 2 assert f.cofactors(g) == (2, 1, x**2 + 2*x + 1) f, g = 2*x**2 + 4*x + 2, x + 1 assert f.cofactors(g) == (x + 1, 2*x + 2, 1) f, g = x + 1, 2*x**2 + 4*x + 2 assert f.cofactors(g) == (x + 1, 1, 2*x + 2) R, x, y, z, t = ring("x,y,z,t", ZZ) f, g = t**2 + 2*t + 1, 2*t + 2 assert f.cofactors(g) == (t + 1, t + 1, 2) f, g = z**2*t**2 + 2*z**2*t + z**2 + z*t + z, t**2 + 2*t + 1 h, cff, cfg = t + 1, z**2*t + z**2 + z, t + 1 assert f.cofactors(g) == (h, cff, cfg) assert g.cofactors(f) == (h, cfg, cff) R, x, y = ring("x,y", QQ) f = QQ(1,2)*x**2 + x + QQ(1,2) g = QQ(1,2)*x + QQ(1,2) h = x + 1 assert f.cofactors(g) == (h, g, QQ(1,2)) assert g.cofactors(f) == (h, QQ(1,2), g) R, x, y = ring("x,y", RR) f = 2.1*x*y**2 - 2.1*x*y + 2.1*x g = 2.1*x**3 h = 1.0*x assert f.cofactors(g) == (h, f/h, g/h) assert g.cofactors(f) == (h, g/h, f/h) def test_PolyElement_gcd(): R, x, y = ring("x,y", QQ) f = QQ(1,2)*x**2 + x + QQ(1,2) g = QQ(1,2)*x + QQ(1,2) assert f.gcd(g) == x + 1 def test_PolyElement_cancel(): R, x, y = ring("x,y", ZZ) f = 2*x**3 + 4*x**2 + 2*x g = 3*x**2 + 3*x F = 2*x + 2 G = 3 assert f.cancel(g) == (F, G) assert (-f).cancel(g) == (-F, G) assert f.cancel(-g) == (-F, G) R, x, y = ring("x,y", QQ) f = QQ(1,2)*x**3 + x**2 + QQ(1,2)*x g = QQ(1,3)*x**2 + QQ(1,3)*x F = 3*x + 3 G = 2 assert f.cancel(g) == (F, G) assert (-f).cancel(g) == (-F, G) assert f.cancel(-g) == (-F, G) Fx, x = field("x", ZZ) Rt, t = ring("t", Fx) f = (-x**2 - 4)/4*t g = t**2 + (x**2 + 2)/2 assert f.cancel(g) == ((-x**2 - 4)*t, 4*t**2 + 2*x**2 + 4) def test_PolyElement_max_norm(): R, x, y = ring("x,y", ZZ) assert R(0).max_norm() == 0 assert R(1).max_norm() == 1 assert (x**3 + 4*x**2 + 2*x + 3).max_norm() == 4 def test_PolyElement_l1_norm(): R, x, y = ring("x,y", ZZ) assert R(0).l1_norm() == 0 assert R(1).l1_norm() == 1 assert (x**3 + 4*x**2 + 2*x + 3).l1_norm() == 10 def test_PolyElement_diff(): R, X = xring("x:11", QQ) f = QQ(288,5)*X[0]**8*X[1]**6*X[4]**3*X[10]**2 + 8*X[0]**2*X[2]**3*X[4]**3 +2*X[0]**2 - 2*X[1]**2 assert f.diff(X[0]) == QQ(2304,5)*X[0]**7*X[1]**6*X[4]**3*X[10]**2 + 16*X[0]*X[2]**3*X[4]**3 + 4*X[0] assert f.diff(X[4]) == QQ(864,5)*X[0]**8*X[1]**6*X[4]**2*X[10]**2 + 24*X[0]**2*X[2]**3*X[4]**2 assert f.diff(X[10]) == QQ(576,5)*X[0]**8*X[1]**6*X[4]**3*X[10] def test_PolyElement___call__(): R, x = ring("x", ZZ) f = 3*x + 1 assert f(0) == 1 assert f(1) == 4 raises(ValueError, lambda: f()) raises(ValueError, lambda: f(0, 1)) raises(CoercionFailed, lambda: f(QQ(1,7))) R, x,y = ring("x,y", ZZ) f = 3*x + y**2 + 1 assert f(0, 0) == 1 assert f(1, 7) == 53 Ry = R.drop(x) assert f(0) == Ry.y**2 + 1 assert f(1) == Ry.y**2 + 4 raises(ValueError, lambda: f()) raises(ValueError, lambda: f(0, 1, 2)) raises(CoercionFailed, lambda: f(1, QQ(1,7))) raises(CoercionFailed, lambda: f(QQ(1,7), 1)) raises(CoercionFailed, lambda: f(QQ(1,7), QQ(1,7))) def test_PolyElement_evaluate(): R, x = ring("x", ZZ) f = x**3 + 4*x**2 + 2*x + 3 r = f.evaluate(x, 0) assert r == 3 and not isinstance(r, PolyElement) raises(CoercionFailed, lambda: f.evaluate(x, QQ(1,7))) R, x, y, z = ring("x,y,z", ZZ) f = (x*y)**3 + 4*(x*y)**2 + 2*x*y + 3 r = f.evaluate(x, 0) assert r == 3 and isinstance(r, R.drop(x).dtype) r = f.evaluate([(x, 0), (y, 0)]) assert r == 3 and isinstance(r, R.drop(x, y).dtype) r = f.evaluate(y, 0) assert r == 3 and isinstance(r, R.drop(y).dtype) r = f.evaluate([(y, 0), (x, 0)]) assert r == 3 and isinstance(r, R.drop(y, x).dtype) r = f.evaluate([(x, 0), (y, 0), (z, 0)]) assert r == 3 and not isinstance(r, PolyElement) raises(CoercionFailed, lambda: f.evaluate([(x, 1), (y, QQ(1,7))])) raises(CoercionFailed, lambda: f.evaluate([(x, QQ(1,7)), (y, 1)])) raises(CoercionFailed, lambda: f.evaluate([(x, QQ(1,7)), (y, QQ(1,7))])) def test_PolyElement_subs(): R, x = ring("x", ZZ) f = x**3 + 4*x**2 + 2*x + 3 r = f.subs(x, 0) assert r == 3 and isinstance(r, R.dtype) raises(CoercionFailed, lambda: f.subs(x, QQ(1,7))) R, x, y, z = ring("x,y,z", ZZ) f = x**3 + 4*x**2 + 2*x + 3 r = f.subs(x, 0) assert r == 3 and isinstance(r, R.dtype) r = f.subs([(x, 0), (y, 0)]) assert r == 3 and isinstance(r, R.dtype) raises(CoercionFailed, lambda: f.subs([(x, 1), (y, QQ(1,7))])) raises(CoercionFailed, lambda: f.subs([(x, QQ(1,7)), (y, 1)])) raises(CoercionFailed, lambda: f.subs([(x, QQ(1,7)), (y, QQ(1,7))])) def test_PolyElement_compose(): R, x = ring("x", ZZ) f = x**3 + 4*x**2 + 2*x + 3 r = f.compose(x, 0) assert r == 3 and isinstance(r, R.dtype) assert f.compose(x, x) == f assert f.compose(x, x**2) == x**6 + 4*x**4 + 2*x**2 + 3 raises(CoercionFailed, lambda: f.compose(x, QQ(1,7))) R, x, y, z = ring("x,y,z", ZZ) f = x**3 + 4*x**2 + 2*x + 3 r = f.compose(x, 0) assert r == 3 and isinstance(r, R.dtype) r = f.compose([(x, 0), (y, 0)]) assert r == 3 and isinstance(r, R.dtype) r = (x**3 + 4*x**2 + 2*x*y*z + 3).compose(x, y*z**2 - 1) q = (y*z**2 - 1)**3 + 4*(y*z**2 - 1)**2 + 2*(y*z**2 - 1)*y*z + 3 assert r == q and isinstance(r, R.dtype) def test_PolyElement_is_(): R, x,y,z = ring("x,y,z", QQ) assert (x - x).is_generator == False assert (x - x).is_ground == True assert (x - x).is_monomial == True assert (x - x).is_term == True assert (x - x + 1).is_generator == False assert (x - x + 1).is_ground == True assert (x - x + 1).is_monomial == True assert (x - x + 1).is_term == True assert x.is_generator == True assert x.is_ground == False assert x.is_monomial == True assert x.is_term == True assert (x*y).is_generator == False assert (x*y).is_ground == False assert (x*y).is_monomial == True assert (x*y).is_term == True assert (3*x).is_generator == False assert (3*x).is_ground == False assert (3*x).is_monomial == False assert (3*x).is_term == True assert (3*x + 1).is_generator == False assert (3*x + 1).is_ground == False assert (3*x + 1).is_monomial == False assert (3*x + 1).is_term == False assert R(0).is_zero is True assert R(1).is_zero is False assert R(0).is_one is False assert R(1).is_one is True assert (x - 1).is_monic is True assert (2*x - 1).is_monic is False assert (3*x + 2).is_primitive is True assert (4*x + 2).is_primitive is False assert (x + y + z + 1).is_linear is True assert (x*y*z + 1).is_linear is False assert (x*y + z + 1).is_quadratic is True assert (x*y*z + 1).is_quadratic is False assert (x - 1).is_squarefree is True assert ((x - 1)**2).is_squarefree is False assert (x**2 + x + 1).is_irreducible is True assert (x**2 + 2*x + 1).is_irreducible is False _, t = ring("t", FF(11)) assert (7*t + 3).is_irreducible is True assert (7*t**2 + 3*t + 1).is_irreducible is False _, u = ring("u", ZZ) f = u**16 + u**14 - u**10 - u**8 - u**6 + u**2 assert f.is_cyclotomic is False assert (f + 1).is_cyclotomic is True raises(MultivariatePolynomialError, lambda: x.is_cyclotomic) R, = ring("", ZZ) assert R(4).is_squarefree is True assert R(6).is_irreducible is True def test_PolyElement_drop(): R, x,y,z = ring("x,y,z", ZZ) assert R(1).drop(0).ring == PolyRing("y,z", ZZ, lex) assert R(1).drop(0).drop(0).ring == PolyRing("z", ZZ, lex) assert isinstance(R(1).drop(0).drop(0).drop(0), R.dtype) is False raises(ValueError, lambda: z.drop(0).drop(0).drop(0)) raises(ValueError, lambda: x.drop(0)) def test_PolyElement_pdiv(): _, x, y = ring("x,y", ZZ) f, g = x**2 - y**2, x - y q, r = x + y, 0 assert f.pdiv(g) == (q, r) assert f.prem(g) == r assert f.pquo(g) == q assert f.pexquo(g) == q def test_PolyElement_gcdex(): _, x = ring("x", QQ) f, g = 2*x, x**2 - 16 s, t, h = x/32, -QQ(1, 16), 1 assert f.half_gcdex(g) == (s, h) assert f.gcdex(g) == (s, t, h) def test_PolyElement_subresultants(): _, x = ring("x", ZZ) f, g, h = x**2 - 2*x + 1, x**2 - 1, 2*x - 2 assert f.subresultants(g) == [f, g, h] def test_PolyElement_resultant(): _, x = ring("x", ZZ) f, g, h = x**2 - 2*x + 1, x**2 - 1, 0 assert f.resultant(g) == h def test_PolyElement_discriminant(): _, x = ring("x", ZZ) f, g = x**3 + 3*x**2 + 9*x - 13, -11664 assert f.discriminant() == g F, a, b, c = ring("a,b,c", ZZ) _, x = ring("x", F) f, g = a*x**2 + b*x + c, b**2 - 4*a*c assert f.discriminant() == g def test_PolyElement_decompose(): _, x = ring("x", ZZ) f = x**12 + 20*x**10 + 150*x**8 + 500*x**6 + 625*x**4 - 2*x**3 - 10*x + 9 g = x**4 - 2*x + 9 h = x**3 + 5*x assert g.compose(x, h) == f assert f.decompose() == [g, h] def test_PolyElement_shift(): _, x = ring("x", ZZ) assert (x**2 - 2*x + 1).shift(2) == x**2 + 2*x + 1 def test_PolyElement_sturm(): F, t = field("t", ZZ) _, x = ring("x", F) f = 1024/(15625*t**8)*x**5 - 4096/(625*t**8)*x**4 + 32/(15625*t**4)*x**3 - 128/(625*t**4)*x**2 + F(1)/62500*x - F(1)/625 assert f.sturm() == [ x**3 - 100*x**2 + t**4/64*x - 25*t**4/16, 3*x**2 - 200*x + t**4/64, (-t**4/96 + F(20000)/9)*x + 25*t**4/18, (-9*t**12 - 11520000*t**8 - 3686400000000*t**4)/(576*t**8 - 245760000*t**4 + 26214400000000), ] def test_PolyElement_gff_list(): _, x = ring("x", ZZ) f = x**5 + 2*x**4 - x**3 - 2*x**2 assert f.gff_list() == [(x, 1), (x + 2, 4)] f = x*(x - 1)**3*(x - 2)**2*(x - 4)**2*(x - 5) assert f.gff_list() == [(x**2 - 5*x + 4, 1), (x**2 - 5*x + 4, 2), (x, 3)] def test_PolyElement_sqf_norm(): R, x = ring("x", QQ.algebraic_field(sqrt(3))) X = R.to_ground().x assert (x**2 - 2).sqf_norm() == (1, x**2 - 2*sqrt(3)*x + 1, X**4 - 10*X**2 + 1) R, x = ring("x", QQ.algebraic_field(sqrt(2))) X = R.to_ground().x assert (x**2 - 3).sqf_norm() == (1, x**2 - 2*sqrt(2)*x - 1, X**4 - 10*X**2 + 1) def test_PolyElement_sqf_list(): _, x = ring("x", ZZ) f = x**5 - x**3 - x**2 + 1 g = x**3 + 2*x**2 + 2*x + 1 h = x - 1 p = x**4 + x**3 - x - 1 assert f.sqf_part() == p assert f.sqf_list() == (1, [(g, 1), (h, 2)]) def test_PolyElement_factor_list(): _, x = ring("x", ZZ) f = x**5 - x**3 - x**2 + 1 u = x + 1 v = x - 1 w = x**2 + x + 1 assert f.factor_list() == (1, [(u, 1), (v, 2), (w, 1)]) def test_issue_21410(): R, x = ring('x', FF(2)) p = x**6 + x**5 + x**4 + x**3 + 1 assert p._pow_multinomial(4) == x**24 + x**20 + x**16 + x**12 + 1
8366120600623f84e454f2b0ed48fbc7cb2569bdbd2f528541206c7ef836a03c
"""Tests for tools for constructing domains for expressions. """ from sympy.polys.constructor import construct_domain from sympy.polys.domains import ZZ, QQ, ZZ_I, QQ_I, RR, CC, EX from sympy.polys.domains.realfield import RealField from sympy.polys.domains.complexfield import ComplexField from sympy import ( S, sqrt, sin, exp, Float, E, I, GoldenRatio, pi, Catalan, Rational) from sympy.abc import x, y def test_construct_domain(): assert construct_domain([1, 2, 3]) == (ZZ, [ZZ(1), ZZ(2), ZZ(3)]) assert construct_domain([1, 2, 3], field=True) == (QQ, [QQ(1), QQ(2), QQ(3)]) assert construct_domain([S.One, S(2), S(3)]) == (ZZ, [ZZ(1), ZZ(2), ZZ(3)]) assert construct_domain([S.One, S(2), S(3)], field=True) == (QQ, [QQ(1), QQ(2), QQ(3)]) assert construct_domain([S.Half, S(2)]) == (QQ, [QQ(1, 2), QQ(2)]) result = construct_domain([3.14, 1, S.Half]) assert isinstance(result[0], RealField) assert result[1] == [RR(3.14), RR(1.0), RR(0.5)] result = construct_domain([3.14, I, S.Half]) assert isinstance(result[0], ComplexField) assert result[1] == [CC(3.14), CC(1.0j), CC(0.5)] assert construct_domain([1.0+I]) == (CC, [CC(1.0, 1.0)]) assert construct_domain([2.0+3.0*I]) == (CC, [CC(2.0, 3.0)]) assert construct_domain([1, I]) == (ZZ_I, [ZZ_I(1, 0), ZZ_I(0, 1)]) assert construct_domain([1, I/2]) == (QQ_I, [QQ_I(1, 0), QQ_I(0, S.Half)]) assert construct_domain([3.14, sqrt(2)], extension=None) == (EX, [EX(3.14), EX(sqrt(2))]) assert construct_domain([3.14, sqrt(2)], extension=True) == (EX, [EX(3.14), EX(sqrt(2))]) assert construct_domain([1, sqrt(2)], extension=None) == (EX, [EX(1), EX(sqrt(2))]) assert construct_domain([x, sqrt(x)]) == (EX, [EX(x), EX(sqrt(x))]) assert construct_domain([x, sqrt(x), sqrt(y)]) == (EX, [EX(x), EX(sqrt(x)), EX(sqrt(y))]) alg = QQ.algebraic_field(sqrt(2)) assert construct_domain([7, S.Half, sqrt(2)], extension=True) == \ (alg, [alg.convert(7), alg.convert(S.Half), alg.convert(sqrt(2))]) alg = QQ.algebraic_field(sqrt(2) + sqrt(3)) assert construct_domain([7, sqrt(2), sqrt(3)], extension=True) == \ (alg, [alg.convert(7), alg.convert(sqrt(2)), alg.convert(sqrt(3))]) dom = ZZ[x] assert construct_domain([2*x, 3]) == \ (dom, [dom.convert(2*x), dom.convert(3)]) dom = ZZ[x, y] assert construct_domain([2*x, 3*y]) == \ (dom, [dom.convert(2*x), dom.convert(3*y)]) dom = QQ[x] assert construct_domain([x/2, 3]) == \ (dom, [dom.convert(x/2), dom.convert(3)]) dom = QQ[x, y] assert construct_domain([x/2, 3*y]) == \ (dom, [dom.convert(x/2), dom.convert(3*y)]) dom = ZZ_I[x] assert construct_domain([2*x, I]) == \ (dom, [dom.convert(2*x), dom.convert(I)]) dom = ZZ_I[x, y] assert construct_domain([2*x, I*y]) == \ (dom, [dom.convert(2*x), dom.convert(I*y)]) dom = QQ_I[x] assert construct_domain([x/2, I]) == \ (dom, [dom.convert(x/2), dom.convert(I)]) dom = QQ_I[x, y] assert construct_domain([x/2, I*y]) == \ (dom, [dom.convert(x/2), dom.convert(I*y)]) dom = RR[x] assert construct_domain([x/2, 3.5]) == \ (dom, [dom.convert(x/2), dom.convert(3.5)]) dom = RR[x, y] assert construct_domain([x/2, 3.5*y]) == \ (dom, [dom.convert(x/2), dom.convert(3.5*y)]) dom = CC[x] assert construct_domain([I*x/2, 3.5]) == \ (dom, [dom.convert(I*x/2), dom.convert(3.5)]) dom = CC[x, y] assert construct_domain([I*x/2, 3.5*y]) == \ (dom, [dom.convert(I*x/2), dom.convert(3.5*y)]) dom = CC[x] assert construct_domain([x/2, I*3.5]) == \ (dom, [dom.convert(x/2), dom.convert(I*3.5)]) dom = CC[x, y] assert construct_domain([x/2, I*3.5*y]) == \ (dom, [dom.convert(x/2), dom.convert(I*3.5*y)]) dom = ZZ.frac_field(x) assert construct_domain([2/x, 3]) == \ (dom, [dom.convert(2/x), dom.convert(3)]) dom = ZZ.frac_field(x, y) assert construct_domain([2/x, 3*y]) == \ (dom, [dom.convert(2/x), dom.convert(3*y)]) dom = RR.frac_field(x) assert construct_domain([2/x, 3.5]) == \ (dom, [dom.convert(2/x), dom.convert(3.5)]) dom = RR.frac_field(x, y) assert construct_domain([2/x, 3.5*y]) == \ (dom, [dom.convert(2/x), dom.convert(3.5*y)]) dom = RealField(prec=336)[x] assert construct_domain([pi.evalf(100)*x]) == \ (dom, [dom.convert(pi.evalf(100)*x)]) assert construct_domain(2) == (ZZ, ZZ(2)) assert construct_domain(S(2)/3) == (QQ, QQ(2, 3)) assert construct_domain(Rational(2, 3)) == (QQ, QQ(2, 3)) assert construct_domain({}) == (ZZ, {}) def test_complex_exponential(): w = exp(-I*2*pi/3, evaluate=False) alg = QQ.algebraic_field(w) assert construct_domain([w**2, w, 1], extension=True) == ( alg, [alg.convert(w**2), alg.convert(w), alg.convert(1)] ) def test_composite_option(): assert construct_domain({(1,): sin(y)}, composite=False) == \ (EX, {(1,): EX(sin(y))}) assert construct_domain({(1,): y}, composite=False) == \ (EX, {(1,): EX(y)}) assert construct_domain({(1, 1): 1}, composite=False) == \ (ZZ, {(1, 1): 1}) assert construct_domain({(1, 0): y}, composite=False) == \ (EX, {(1, 0): EX(y)}) def test_precision(): f1 = Float("1.01") f2 = Float("1.0000000000000000000001") for u in [1, 1e-2, 1e-6, 1e-13, 1e-14, 1e-16, 1e-20, 1e-100, 1e-300, f1, f2]: result = construct_domain([u]) v = float(result[1][0]) assert abs(u - v) / u < 1e-14 # Test relative accuracy result = construct_domain([f1]) y = result[1][0] assert y-1 > 1e-50 result = construct_domain([f2]) y = result[1][0] assert y-1 > 1e-50 def test_issue_11538(): for n in [E, pi, Catalan]: assert construct_domain(n)[0] == ZZ[n] assert construct_domain(x + n)[0] == ZZ[x, n] assert construct_domain(GoldenRatio)[0] == EX assert construct_domain(x + GoldenRatio)[0] == EX
098e01dc397100bedad14e6baca858a231838fb9627bfdd3f9fdcbbed9063927
"""Tests for computational algebraic number field theory. """ from sympy import (S, Rational, Symbol, Poly, sqrt, I, oo, Tuple, expand, pi, cos, sin, tan, exp, GoldenRatio, TribonacciConstant, cbrt) from sympy.solvers.solveset import nonlinsolve from sympy.geometry import Circle, intersection from sympy.testing.pytest import raises, slow from sympy.sets.sets import FiniteSet from sympy import Point2D from sympy.polys.numberfields import ( minimal_polynomial, primitive_element, is_isomorphism_possible, field_isomorphism_pslq, field_isomorphism, to_number_field, AlgebraicNumber, isolate, IntervalPrinter, _choose_factor, ) from sympy.polys.partfrac import apart from sympy.polys.polyerrors import ( IsomorphismFailed, NotAlgebraic, GeneratorsError, ) from sympy.polys.polyclasses import DMP from sympy.polys.domains import QQ from sympy.polys.rootoftools import rootof from sympy.polys.polytools import degree from sympy.abc import x, y, z Q = Rational def test_minimal_polynomial(): assert minimal_polynomial(-7, x) == x + 7 assert minimal_polynomial(-1, x) == x + 1 assert minimal_polynomial( 0, x) == x assert minimal_polynomial( 1, x) == x - 1 assert minimal_polynomial( 7, x) == x - 7 assert minimal_polynomial(sqrt(2), x) == x**2 - 2 assert minimal_polynomial(sqrt(5), x) == x**2 - 5 assert minimal_polynomial(sqrt(6), x) == x**2 - 6 assert minimal_polynomial(2*sqrt(2), x) == x**2 - 8 assert minimal_polynomial(3*sqrt(5), x) == x**2 - 45 assert minimal_polynomial(4*sqrt(6), x) == x**2 - 96 assert minimal_polynomial(2*sqrt(2) + 3, x) == x**2 - 6*x + 1 assert minimal_polynomial(3*sqrt(5) + 6, x) == x**2 - 12*x - 9 assert minimal_polynomial(4*sqrt(6) + 7, x) == x**2 - 14*x - 47 assert minimal_polynomial(2*sqrt(2) - 3, x) == x**2 + 6*x + 1 assert minimal_polynomial(3*sqrt(5) - 6, x) == x**2 + 12*x - 9 assert minimal_polynomial(4*sqrt(6) - 7, x) == x**2 + 14*x - 47 assert minimal_polynomial(sqrt(1 + sqrt(6)), x) == x**4 - 2*x**2 - 5 assert minimal_polynomial(sqrt(I + sqrt(6)), x) == x**8 - 10*x**4 + 49 assert minimal_polynomial(2*I + sqrt(2 + I), x) == x**4 + 4*x**2 + 8*x + 37 assert minimal_polynomial(sqrt(2) + sqrt(3), x) == x**4 - 10*x**2 + 1 assert minimal_polynomial( sqrt(2) + sqrt(3) + sqrt(6), x) == x**4 - 22*x**2 - 48*x - 23 a = 1 - 9*sqrt(2) + 7*sqrt(3) assert minimal_polynomial( 1/a, x) == 392*x**4 - 1232*x**3 + 612*x**2 + 4*x - 1 assert minimal_polynomial( 1/sqrt(a), x) == 392*x**8 - 1232*x**6 + 612*x**4 + 4*x**2 - 1 raises(NotAlgebraic, lambda: minimal_polynomial(oo, x)) raises(NotAlgebraic, lambda: minimal_polynomial(2**y, x)) raises(NotAlgebraic, lambda: minimal_polynomial(sin(1), x)) assert minimal_polynomial(sqrt(2)).dummy_eq(x**2 - 2) assert minimal_polynomial(sqrt(2), x) == x**2 - 2 assert minimal_polynomial(sqrt(2), polys=True) == Poly(x**2 - 2) assert minimal_polynomial(sqrt(2), x, polys=True) == Poly(x**2 - 2, domain='QQ') assert minimal_polynomial(sqrt(2), x, polys=True, compose=False) == Poly(x**2 - 2, domain='QQ') a = AlgebraicNumber(sqrt(2)) b = AlgebraicNumber(sqrt(3)) assert minimal_polynomial(a, x) == x**2 - 2 assert minimal_polynomial(b, x) == x**2 - 3 assert minimal_polynomial(a, x, polys=True) == Poly(x**2 - 2, domain='QQ') assert minimal_polynomial(b, x, polys=True) == Poly(x**2 - 3, domain='QQ') assert minimal_polynomial(sqrt(a/2 + 17), x) == 2*x**4 - 68*x**2 + 577 assert minimal_polynomial(sqrt(b/2 + 17), x) == 4*x**4 - 136*x**2 + 1153 a, b = sqrt(2)/3 + 7, AlgebraicNumber(sqrt(2)/3 + 7) f = 81*x**8 - 2268*x**6 - 4536*x**5 + 22644*x**4 + 63216*x**3 - \ 31608*x**2 - 189648*x + 141358 assert minimal_polynomial(sqrt(a) + sqrt(sqrt(a)), x) == f assert minimal_polynomial(sqrt(b) + sqrt(sqrt(b)), x) == f assert minimal_polynomial( a**Q(3, 2), x) == 729*x**4 - 506898*x**2 + 84604519 # issue 5994 eq = S(''' -1/(800*sqrt(-1/240 + 1/(18000*(-1/17280000 + sqrt(15)*I/28800000)**(1/3)) + 2*(-1/17280000 + sqrt(15)*I/28800000)**(1/3)))''') assert minimal_polynomial(eq, x) == 8000*x**2 - 1 ex = (sqrt(5)*sqrt(I)/(5*sqrt(1 + 125*I)) + 25*sqrt(5)/(I**Q(5,2)*(1 + 125*I)**Q(3,2)) + 3125*sqrt(5)/(I**Q(11,2)*(1 + 125*I)**Q(3,2)) + 5*I*sqrt(1 - I/125)) mp = minimal_polynomial(ex, x) assert mp == 25*x**4 + 5000*x**2 + 250016 ex = 1 + sqrt(2) + sqrt(3) mp = minimal_polynomial(ex, x) assert mp == x**4 - 4*x**3 - 4*x**2 + 16*x - 8 ex = 1/(1 + sqrt(2) + sqrt(3)) mp = minimal_polynomial(ex, x) assert mp == 8*x**4 - 16*x**3 + 4*x**2 + 4*x - 1 p = (expand((1 + sqrt(2) - 2*sqrt(3) + sqrt(7))**3))**Rational(1, 3) mp = minimal_polynomial(p, x) assert mp == x**8 - 8*x**7 - 56*x**6 + 448*x**5 + 480*x**4 - 5056*x**3 + 1984*x**2 + 7424*x - 3008 p = expand((1 + sqrt(2) - 2*sqrt(3) + sqrt(7))**3) mp = minimal_polynomial(p, x) assert mp == x**8 - 512*x**7 - 118208*x**6 + 31131136*x**5 + 647362560*x**4 - 56026611712*x**3 + 116994310144*x**2 + 404854931456*x - 27216576512 assert minimal_polynomial(S("-sqrt(5)/2 - 1/2 + (-sqrt(5)/2 - 1/2)**2"), x) == x - 1 a = 1 + sqrt(2) assert minimal_polynomial((a*sqrt(2) + a)**3, x) == x**2 - 198*x + 1 p = 1/(1 + sqrt(2) + sqrt(3)) assert minimal_polynomial(p, x, compose=False) == 8*x**4 - 16*x**3 + 4*x**2 + 4*x - 1 p = 2/(1 + sqrt(2) + sqrt(3)) assert minimal_polynomial(p, x, compose=False) == x**4 - 4*x**3 + 2*x**2 + 4*x - 2 assert minimal_polynomial(1 + sqrt(2)*I, x, compose=False) == x**2 - 2*x + 3 assert minimal_polynomial(1/(1 + sqrt(2)) + 1, x, compose=False) == x**2 - 2 assert minimal_polynomial(sqrt(2)*I + I*(1 + sqrt(2)), x, compose=False) == x**4 + 18*x**2 + 49 # minimal polynomial of I assert minimal_polynomial(I, x, domain=QQ.algebraic_field(I)) == x - I K = QQ.algebraic_field(I*(sqrt(2) + 1)) assert minimal_polynomial(I, x, domain=K) == x - I assert minimal_polynomial(I, x, domain=QQ) == x**2 + 1 assert minimal_polynomial(I, x, domain='QQ(y)') == x**2 + 1 #issue 11553 assert minimal_polynomial(GoldenRatio, x) == x**2 - x - 1 assert minimal_polynomial(TribonacciConstant + 3, x) == x**3 - 10*x**2 + 32*x - 34 assert minimal_polynomial(GoldenRatio, x, domain=QQ.algebraic_field(sqrt(5))) == \ 2*x - sqrt(5) - 1 assert minimal_polynomial(TribonacciConstant, x, domain=QQ.algebraic_field(cbrt(19 - 3*sqrt(33)))) == \ 48*x - 19*(19 - 3*sqrt(33))**Rational(2, 3) - 3*sqrt(33)*(19 - 3*sqrt(33))**Rational(2, 3) \ - 16*(19 - 3*sqrt(33))**Rational(1, 3) - 16 # AlgebraicNumber with an alias. # Wester H24 phi = AlgebraicNumber(S.GoldenRatio.expand(func=True), alias='phi') minimal_polynomial(phi, x) == x**2 - x - 1 def test_minimal_polynomial_issue_19732(): # https://github.com/sympy/sympy/issues/19732 expr = (-280898097948878450887044002323982963174671632174995451265117559518123750720061943079105185551006003416773064305074191140286225850817291393988597615/(-488144716373031204149459129212782509078221364279079444636386844223983756114492222145074506571622290776245390771587888364089507840000000*sqrt(238368341569)*sqrt(S(11918417078450)/63568729 - 24411360*sqrt(238368341569)/63568729) + 238326799225996604451373809274348704114327860564921529846705817404208077866956345381951726531296652901169111729944612727047670549086208000000*sqrt(S(11918417078450)/63568729 - 24411360*sqrt(238368341569)/63568729)) - 180561807339168676696180573852937120123827201075968945871075967679148461189459480842956689723484024031016208588658753107/(-59358007109636562851035004992802812513575019937126272896569856090962677491318275291141463850327474176000000*sqrt(238368341569)*sqrt(S(11918417078450)/63568729 - 24411360*sqrt(238368341569)/63568729) + 28980348180319251787320809875930301310576055074938369007463004788921613896002936637780993064387310446267596800000*sqrt(S(11918417078450)/63568729 - 24411360*sqrt(238368341569)/63568729))) poly = (2151288870990266634727173620565483054187142169311153766675688628985237817262915166497766867289157986631135400926544697981091151416655364879773546003475813114962656742744975460025956167152918469472166170500512008351638710934022160294849059721218824490226159355197136265032810944357335461128949781377875451881300105989490353140886315677977149440000000000000000000000*x**4 - 5773274155644072033773937864114266313663195672820501581692669271302387257492905909558846459600429795784309388968498783843631580008547382703258503404023153694528041873101120067477617592651525155101107144042679962433039557235772239171616433004024998230222455940044709064078962397144550855715640331680262171410099614469231080995436488414164502751395405398078353242072696360734131090111239998110773292915337556205692674790561090109440000000000000*x**2 + 211295968822207088328287206509522887719741955693091053353263782924470627623790749534705683380138972642560898936171035770539616881000369889020398551821767092685775598633794696371561234818461806577723412581353857653829324364446419444210520602157621008010129702779407422072249192199762604318993590841636967747488049176548615614290254356975376588506729604345612047361483789518445332415765213187893207704958013682516462853001964919444736320672860140355089) assert minimal_polynomial(expr, x) == poly def test_minimal_polynomial_hi_prec(): p = 1/sqrt(1 - 9*sqrt(2) + 7*sqrt(3) + Rational(1, 10)**30) mp = minimal_polynomial(p, x) # checked with Wolfram Alpha assert mp.coeff(x**6) == -1232000000000000000000000000001223999999999999999999999999999987999999999999999999999999999996000000000000000000000000000000 def test_minimal_polynomial_sq(): from sympy import Add, expand_multinomial p = expand_multinomial((1 + 5*sqrt(2) + 2*sqrt(3))**3) mp = minimal_polynomial(p**Rational(1, 3), x) assert mp == x**4 - 4*x**3 - 118*x**2 + 244*x + 1321 p = expand_multinomial((1 + sqrt(2) - 2*sqrt(3) + sqrt(7))**3) mp = minimal_polynomial(p**Rational(1, 3), x) assert mp == x**8 - 8*x**7 - 56*x**6 + 448*x**5 + 480*x**4 - 5056*x**3 + 1984*x**2 + 7424*x - 3008 p = Add(*[sqrt(i) for i in range(1, 12)]) mp = minimal_polynomial(p, x) assert mp.subs({x: 0}) == -71965773323122507776 def test_minpoly_compose(): # issue 6868 eq = S(''' -1/(800*sqrt(-1/240 + 1/(18000*(-1/17280000 + sqrt(15)*I/28800000)**(1/3)) + 2*(-1/17280000 + sqrt(15)*I/28800000)**(1/3)))''') mp = minimal_polynomial(eq + 3, x) assert mp == 8000*x**2 - 48000*x + 71999 # issue 5888 assert minimal_polynomial(exp(I*pi/8), x) == x**8 + 1 mp = minimal_polynomial(sin(pi/7) + sqrt(2), x) assert mp == 4096*x**12 - 63488*x**10 + 351488*x**8 - 826496*x**6 + \ 770912*x**4 - 268432*x**2 + 28561 mp = minimal_polynomial(cos(pi/7) + sqrt(2), x) assert mp == 64*x**6 - 64*x**5 - 432*x**4 + 304*x**3 + 712*x**2 - \ 232*x - 239 mp = minimal_polynomial(exp(I*pi/7) + sqrt(2), x) assert mp == x**12 - 2*x**11 - 9*x**10 + 16*x**9 + 43*x**8 - 70*x**7 - 97*x**6 + 126*x**5 + 211*x**4 - 212*x**3 - 37*x**2 + 142*x + 127 mp = minimal_polynomial(sin(pi/7) + sqrt(2), x) assert mp == 4096*x**12 - 63488*x**10 + 351488*x**8 - 826496*x**6 + \ 770912*x**4 - 268432*x**2 + 28561 mp = minimal_polynomial(cos(pi/7) + sqrt(2), x) assert mp == 64*x**6 - 64*x**5 - 432*x**4 + 304*x**3 + 712*x**2 - \ 232*x - 239 mp = minimal_polynomial(exp(I*pi/7) + sqrt(2), x) assert mp == x**12 - 2*x**11 - 9*x**10 + 16*x**9 + 43*x**8 - 70*x**7 - 97*x**6 + 126*x**5 + 211*x**4 - 212*x**3 - 37*x**2 + 142*x + 127 mp = minimal_polynomial(exp(I*pi*Rational(2, 7)), x) assert mp == x**6 + x**5 + x**4 + x**3 + x**2 + x + 1 mp = minimal_polynomial(exp(I*pi*Rational(2, 15)), x) assert mp == x**8 - x**7 + x**5 - x**4 + x**3 - x + 1 mp = minimal_polynomial(cos(pi*Rational(2, 7)), x) assert mp == 8*x**3 + 4*x**2 - 4*x - 1 mp = minimal_polynomial(sin(pi*Rational(2, 7)), x) ex = (5*cos(pi*Rational(2, 7)) - 7)/(9*cos(pi/7) - 5*cos(pi*Rational(3, 7))) mp = minimal_polynomial(ex, x) assert mp == x**3 + 2*x**2 - x - 1 assert minimal_polynomial(-1/(2*cos(pi/7)), x) == x**3 + 2*x**2 - x - 1 assert minimal_polynomial(sin(pi*Rational(2, 15)), x) == \ 256*x**8 - 448*x**6 + 224*x**4 - 32*x**2 + 1 assert minimal_polynomial(sin(pi*Rational(5, 14)), x) == 8*x**3 - 4*x**2 - 4*x + 1 assert minimal_polynomial(cos(pi/15), x) == 16*x**4 + 8*x**3 - 16*x**2 - 8*x + 1 ex = rootof(x**3 +x*4 + 1, 0) mp = minimal_polynomial(ex, x) assert mp == x**3 + 4*x + 1 mp = minimal_polynomial(ex + 1, x) assert mp == x**3 - 3*x**2 + 7*x - 4 assert minimal_polynomial(exp(I*pi/3), x) == x**2 - x + 1 assert minimal_polynomial(exp(I*pi/4), x) == x**4 + 1 assert minimal_polynomial(exp(I*pi/6), x) == x**4 - x**2 + 1 assert minimal_polynomial(exp(I*pi/9), x) == x**6 - x**3 + 1 assert minimal_polynomial(exp(I*pi/10), x) == x**8 - x**6 + x**4 - x**2 + 1 assert minimal_polynomial(sin(pi/9), x) == 64*x**6 - 96*x**4 + 36*x**2 - 3 assert minimal_polynomial(sin(pi/11), x) == 1024*x**10 - 2816*x**8 + \ 2816*x**6 - 1232*x**4 + 220*x**2 - 11 ex = 2**Rational(1, 3)*exp(Rational(2, 3)*I*pi) assert minimal_polynomial(ex, x) == x**3 - 2 raises(NotAlgebraic, lambda: minimal_polynomial(cos(pi*sqrt(2)), x)) raises(NotAlgebraic, lambda: minimal_polynomial(sin(pi*sqrt(2)), x)) raises(NotAlgebraic, lambda: minimal_polynomial(exp(I*pi*sqrt(2)), x)) # issue 5934 ex = 1/(-36000 - 7200*sqrt(5) + (12*sqrt(10)*sqrt(sqrt(5) + 5) + 24*sqrt(10)*sqrt(-sqrt(5) + 5))**2) + 1 raises(ZeroDivisionError, lambda: minimal_polynomial(ex, x)) ex = sqrt(1 + 2**Rational(1,3)) + sqrt(1 + 2**Rational(1,4)) + sqrt(2) mp = minimal_polynomial(ex, x) assert degree(mp) == 48 and mp.subs({x:0}) == -16630256576 ex = tan(pi/5, evaluate=False) mp = minimal_polynomial(ex, x) assert mp == x**4 - 10*x**2 + 5 assert mp.subs(x, tan(pi/5)).is_zero ex = tan(pi/6, evaluate=False) mp = minimal_polynomial(ex, x) assert mp == 3*x**2 - 1 assert mp.subs(x, tan(pi/6)).is_zero ex = tan(pi/10, evaluate=False) mp = minimal_polynomial(ex, x) assert mp == 5*x**4 - 10*x**2 + 1 assert mp.subs(x, tan(pi/10)).is_zero raises(NotAlgebraic, lambda: minimal_polynomial(tan(pi*sqrt(2)), x)) def test_minpoly_issue_7113(): # see discussion in https://github.com/sympy/sympy/pull/2234 from sympy.simplify.simplify import nsimplify r = nsimplify(pi, tolerance=0.000000001) mp = minimal_polynomial(r, x) assert mp == 1768292677839237920489538677417507171630859375*x**109 - \ 2734577732179183863586489182929671773182898498218854181690460140337930774573792597743853652058046464 def test_minpoly_issue_7574(): ex = -(-1)**Rational(1, 3) + (-1)**Rational(2,3) assert minimal_polynomial(ex, x) == x + 1 def test_choose_factor(): # Test that this does not enter an infinite loop: bad_factors = [Poly(x-2, x), Poly(x+2, x)] raises(NotImplementedError, lambda: _choose_factor(bad_factors, x, sqrt(3))) def test_primitive_element(): assert primitive_element([sqrt(2)], x) == (x**2 - 2, [1]) assert primitive_element( [sqrt(2), sqrt(3)], x) == (x**4 - 10*x**2 + 1, [1, 1]) assert primitive_element([sqrt(2)], x, polys=True) == (Poly(x**2 - 2, domain='QQ'), [1]) assert primitive_element([sqrt( 2), sqrt(3)], x, polys=True) == (Poly(x**4 - 10*x**2 + 1, domain='QQ'), [1, 1]) assert primitive_element( [sqrt(2)], x, ex=True) == (x**2 - 2, [1], [[1, 0]]) assert primitive_element([sqrt(2), sqrt(3)], x, ex=True) == \ (x**4 - 10*x**2 + 1, [1, 1], [[Q(1, 2), 0, -Q(9, 2), 0], [- Q(1, 2), 0, Q(11, 2), 0]]) assert primitive_element( [sqrt(2)], x, ex=True, polys=True) == (Poly(x**2 - 2, domain='QQ'), [1], [[1, 0]]) assert primitive_element([sqrt(2), sqrt(3)], x, ex=True, polys=True) == \ (Poly(x**4 - 10*x**2 + 1, domain='QQ'), [1, 1], [[Q(1, 2), 0, -Q(9, 2), 0], [-Q(1, 2), 0, Q(11, 2), 0]]) assert primitive_element([sqrt(2)], polys=True) == (Poly(x**2 - 2), [1]) raises(ValueError, lambda: primitive_element([], x, ex=False)) raises(ValueError, lambda: primitive_element([], x, ex=True)) # Issue 14117 a, b = I*sqrt(2*sqrt(2) + 3), I*sqrt(-2*sqrt(2) + 3) assert primitive_element([a, b, I], x) == (x**4 + 6*x**2 + 1, [1, 0, 0]) def test_field_isomorphism_pslq(): a = AlgebraicNumber(I) b = AlgebraicNumber(I*sqrt(3)) raises(NotImplementedError, lambda: field_isomorphism_pslq(a, b)) a = AlgebraicNumber(sqrt(2)) b = AlgebraicNumber(sqrt(3)) c = AlgebraicNumber(sqrt(7)) d = AlgebraicNumber(sqrt(2) + sqrt(3)) e = AlgebraicNumber(sqrt(2) + sqrt(3) + sqrt(7)) assert field_isomorphism_pslq(a, a) == [1, 0] assert field_isomorphism_pslq(a, b) is None assert field_isomorphism_pslq(a, c) is None assert field_isomorphism_pslq(a, d) == [Q(1, 2), 0, -Q(9, 2), 0] assert field_isomorphism_pslq( a, e) == [Q(1, 80), 0, -Q(1, 2), 0, Q(59, 20), 0] assert field_isomorphism_pslq(b, a) is None assert field_isomorphism_pslq(b, b) == [1, 0] assert field_isomorphism_pslq(b, c) is None assert field_isomorphism_pslq(b, d) == [-Q(1, 2), 0, Q(11, 2), 0] assert field_isomorphism_pslq(b, e) == [-Q( 3, 640), 0, Q(67, 320), 0, -Q(297, 160), 0, Q(313, 80), 0] assert field_isomorphism_pslq(c, a) is None assert field_isomorphism_pslq(c, b) is None assert field_isomorphism_pslq(c, c) == [1, 0] assert field_isomorphism_pslq(c, d) is None assert field_isomorphism_pslq(c, e) == [Q( 3, 640), 0, -Q(71, 320), 0, Q(377, 160), 0, -Q(469, 80), 0] assert field_isomorphism_pslq(d, a) is None assert field_isomorphism_pslq(d, b) is None assert field_isomorphism_pslq(d, c) is None assert field_isomorphism_pslq(d, d) == [1, 0] assert field_isomorphism_pslq(d, e) == [-Q( 3, 640), 0, Q(71, 320), 0, -Q(377, 160), 0, Q(549, 80), 0] assert field_isomorphism_pslq(e, a) is None assert field_isomorphism_pslq(e, b) is None assert field_isomorphism_pslq(e, c) is None assert field_isomorphism_pslq(e, d) is None assert field_isomorphism_pslq(e, e) == [1, 0] f = AlgebraicNumber(3*sqrt(2) + 8*sqrt(7) - 5) assert field_isomorphism_pslq( f, e) == [Q(3, 80), 0, -Q(139, 80), 0, Q(347, 20), 0, -Q(761, 20), -5] def test_field_isomorphism(): assert field_isomorphism(3, sqrt(2)) == [3] assert field_isomorphism( I*sqrt(3), I*sqrt(3)/2) == [ 2, 0] assert field_isomorphism(-I*sqrt(3), I*sqrt(3)/2) == [-2, 0] assert field_isomorphism( I*sqrt(3), -I*sqrt(3)/2) == [-2, 0] assert field_isomorphism(-I*sqrt(3), -I*sqrt(3)/2) == [ 2, 0] assert field_isomorphism( 2*I*sqrt(3)/7, 5*I*sqrt(3)/3) == [ Rational(6, 35), 0] assert field_isomorphism(-2*I*sqrt(3)/7, 5*I*sqrt(3)/3) == [Rational(-6, 35), 0] assert field_isomorphism( 2*I*sqrt(3)/7, -5*I*sqrt(3)/3) == [Rational(-6, 35), 0] assert field_isomorphism(-2*I*sqrt(3)/7, -5*I*sqrt(3)/3) == [ Rational(6, 35), 0] assert field_isomorphism( 2*I*sqrt(3)/7 + 27, 5*I*sqrt(3)/3) == [ Rational(6, 35), 27] assert field_isomorphism( -2*I*sqrt(3)/7 + 27, 5*I*sqrt(3)/3) == [Rational(-6, 35), 27] assert field_isomorphism( 2*I*sqrt(3)/7 + 27, -5*I*sqrt(3)/3) == [Rational(-6, 35), 27] assert field_isomorphism( -2*I*sqrt(3)/7 + 27, -5*I*sqrt(3)/3) == [ Rational(6, 35), 27] p = AlgebraicNumber( sqrt(2) + sqrt(3)) q = AlgebraicNumber(-sqrt(2) + sqrt(3)) r = AlgebraicNumber( sqrt(2) - sqrt(3)) s = AlgebraicNumber(-sqrt(2) - sqrt(3)) pos_coeffs = [ S.Half, S.Zero, Rational(-9, 2), S.Zero] neg_coeffs = [Rational(-1, 2), S.Zero, Rational(9, 2), S.Zero] a = AlgebraicNumber(sqrt(2)) assert is_isomorphism_possible(a, p) is True assert is_isomorphism_possible(a, q) is True assert is_isomorphism_possible(a, r) is True assert is_isomorphism_possible(a, s) is True assert field_isomorphism(a, p, fast=True) == pos_coeffs assert field_isomorphism(a, q, fast=True) == neg_coeffs assert field_isomorphism(a, r, fast=True) == pos_coeffs assert field_isomorphism(a, s, fast=True) == neg_coeffs assert field_isomorphism(a, p, fast=False) == pos_coeffs assert field_isomorphism(a, q, fast=False) == neg_coeffs assert field_isomorphism(a, r, fast=False) == pos_coeffs assert field_isomorphism(a, s, fast=False) == neg_coeffs a = AlgebraicNumber(-sqrt(2)) assert is_isomorphism_possible(a, p) is True assert is_isomorphism_possible(a, q) is True assert is_isomorphism_possible(a, r) is True assert is_isomorphism_possible(a, s) is True assert field_isomorphism(a, p, fast=True) == neg_coeffs assert field_isomorphism(a, q, fast=True) == pos_coeffs assert field_isomorphism(a, r, fast=True) == neg_coeffs assert field_isomorphism(a, s, fast=True) == pos_coeffs assert field_isomorphism(a, p, fast=False) == neg_coeffs assert field_isomorphism(a, q, fast=False) == pos_coeffs assert field_isomorphism(a, r, fast=False) == neg_coeffs assert field_isomorphism(a, s, fast=False) == pos_coeffs pos_coeffs = [ S.Half, S.Zero, Rational(-11, 2), S.Zero] neg_coeffs = [Rational(-1, 2), S.Zero, Rational(11, 2), S.Zero] a = AlgebraicNumber(sqrt(3)) assert is_isomorphism_possible(a, p) is True assert is_isomorphism_possible(a, q) is True assert is_isomorphism_possible(a, r) is True assert is_isomorphism_possible(a, s) is True assert field_isomorphism(a, p, fast=True) == neg_coeffs assert field_isomorphism(a, q, fast=True) == neg_coeffs assert field_isomorphism(a, r, fast=True) == pos_coeffs assert field_isomorphism(a, s, fast=True) == pos_coeffs assert field_isomorphism(a, p, fast=False) == neg_coeffs assert field_isomorphism(a, q, fast=False) == neg_coeffs assert field_isomorphism(a, r, fast=False) == pos_coeffs assert field_isomorphism(a, s, fast=False) == pos_coeffs a = AlgebraicNumber(-sqrt(3)) assert is_isomorphism_possible(a, p) is True assert is_isomorphism_possible(a, q) is True assert is_isomorphism_possible(a, r) is True assert is_isomorphism_possible(a, s) is True assert field_isomorphism(a, p, fast=True) == pos_coeffs assert field_isomorphism(a, q, fast=True) == pos_coeffs assert field_isomorphism(a, r, fast=True) == neg_coeffs assert field_isomorphism(a, s, fast=True) == neg_coeffs assert field_isomorphism(a, p, fast=False) == pos_coeffs assert field_isomorphism(a, q, fast=False) == pos_coeffs assert field_isomorphism(a, r, fast=False) == neg_coeffs assert field_isomorphism(a, s, fast=False) == neg_coeffs pos_coeffs = [ Rational(3, 2), S.Zero, Rational(-33, 2), -S(8)] neg_coeffs = [Rational(-3, 2), S.Zero, Rational(33, 2), -S(8)] a = AlgebraicNumber(3*sqrt(3) - 8) assert is_isomorphism_possible(a, p) is True assert is_isomorphism_possible(a, q) is True assert is_isomorphism_possible(a, r) is True assert is_isomorphism_possible(a, s) is True assert field_isomorphism(a, p, fast=True) == neg_coeffs assert field_isomorphism(a, q, fast=True) == neg_coeffs assert field_isomorphism(a, r, fast=True) == pos_coeffs assert field_isomorphism(a, s, fast=True) == pos_coeffs assert field_isomorphism(a, p, fast=False) == neg_coeffs assert field_isomorphism(a, q, fast=False) == neg_coeffs assert field_isomorphism(a, r, fast=False) == pos_coeffs assert field_isomorphism(a, s, fast=False) == pos_coeffs a = AlgebraicNumber(3*sqrt(2) + 2*sqrt(3) + 1) pos_1_coeffs = [ S.Half, S.Zero, Rational(-5, 2), S.One] neg_5_coeffs = [Rational(-5, 2), S.Zero, Rational(49, 2), S.One] pos_5_coeffs = [ Rational(5, 2), S.Zero, Rational(-49, 2), S.One] neg_1_coeffs = [Rational(-1, 2), S.Zero, Rational(5, 2), S.One] assert is_isomorphism_possible(a, p) is True assert is_isomorphism_possible(a, q) is True assert is_isomorphism_possible(a, r) is True assert is_isomorphism_possible(a, s) is True assert field_isomorphism(a, p, fast=True) == pos_1_coeffs assert field_isomorphism(a, q, fast=True) == neg_5_coeffs assert field_isomorphism(a, r, fast=True) == pos_5_coeffs assert field_isomorphism(a, s, fast=True) == neg_1_coeffs assert field_isomorphism(a, p, fast=False) == pos_1_coeffs assert field_isomorphism(a, q, fast=False) == neg_5_coeffs assert field_isomorphism(a, r, fast=False) == pos_5_coeffs assert field_isomorphism(a, s, fast=False) == neg_1_coeffs a = AlgebraicNumber(sqrt(2)) b = AlgebraicNumber(sqrt(3)) c = AlgebraicNumber(sqrt(7)) assert is_isomorphism_possible(a, b) is True assert is_isomorphism_possible(b, a) is True assert is_isomorphism_possible(c, p) is False assert field_isomorphism(sqrt(2), sqrt(3), fast=True) is None assert field_isomorphism(sqrt(3), sqrt(2), fast=True) is None assert field_isomorphism(sqrt(2), sqrt(3), fast=False) is None assert field_isomorphism(sqrt(3), sqrt(2), fast=False) is None def test_to_number_field(): assert to_number_field(sqrt(2)) == AlgebraicNumber(sqrt(2)) assert to_number_field( [sqrt(2), sqrt(3)]) == AlgebraicNumber(sqrt(2) + sqrt(3)) a = AlgebraicNumber(sqrt(2) + sqrt(3), [S.Half, S.Zero, Rational(-9, 2), S.Zero]) assert to_number_field(sqrt(2), sqrt(2) + sqrt(3)) == a assert to_number_field(sqrt(2), AlgebraicNumber(sqrt(2) + sqrt(3))) == a raises(IsomorphismFailed, lambda: to_number_field(sqrt(2), sqrt(3))) def test_AlgebraicNumber(): minpoly, root = x**2 - 2, sqrt(2) a = AlgebraicNumber(root, gen=x) assert a.rep == DMP([QQ(1), QQ(0)], QQ) assert a.root == root assert a.alias is None assert a.minpoly == minpoly assert a.is_number assert a.is_aliased is False assert a.coeffs() == [S.One, S.Zero] assert a.native_coeffs() == [QQ(1), QQ(0)] a = AlgebraicNumber(root, gen=x, alias='y') assert a.rep == DMP([QQ(1), QQ(0)], QQ) assert a.root == root assert a.alias == Symbol('y') assert a.minpoly == minpoly assert a.is_number assert a.is_aliased is True a = AlgebraicNumber(root, gen=x, alias=Symbol('y')) assert a.rep == DMP([QQ(1), QQ(0)], QQ) assert a.root == root assert a.alias == Symbol('y') assert a.minpoly == minpoly assert a.is_number assert a.is_aliased is True assert AlgebraicNumber(sqrt(2), []).rep == DMP([], QQ) assert AlgebraicNumber(sqrt(2), ()).rep == DMP([], QQ) assert AlgebraicNumber(sqrt(2), (0, 0)).rep == DMP([], QQ) assert AlgebraicNumber(sqrt(2), [8]).rep == DMP([QQ(8)], QQ) assert AlgebraicNumber(sqrt(2), [Rational(8, 3)]).rep == DMP([QQ(8, 3)], QQ) assert AlgebraicNumber(sqrt(2), [7, 3]).rep == DMP([QQ(7), QQ(3)], QQ) assert AlgebraicNumber( sqrt(2), [Rational(7, 9), Rational(3, 2)]).rep == DMP([QQ(7, 9), QQ(3, 2)], QQ) assert AlgebraicNumber(sqrt(2), [1, 2, 3]).rep == DMP([QQ(2), QQ(5)], QQ) a = AlgebraicNumber(AlgebraicNumber(root, gen=x), [1, 2]) assert a.rep == DMP([QQ(1), QQ(2)], QQ) assert a.root == root assert a.alias is None assert a.minpoly == minpoly assert a.is_number assert a.is_aliased is False assert a.coeffs() == [S.One, S(2)] assert a.native_coeffs() == [QQ(1), QQ(2)] a = AlgebraicNumber((minpoly, root), [1, 2]) assert a.rep == DMP([QQ(1), QQ(2)], QQ) assert a.root == root assert a.alias is None assert a.minpoly == minpoly assert a.is_number assert a.is_aliased is False a = AlgebraicNumber((Poly(minpoly), root), [1, 2]) assert a.rep == DMP([QQ(1), QQ(2)], QQ) assert a.root == root assert a.alias is None assert a.minpoly == minpoly assert a.is_number assert a.is_aliased is False assert AlgebraicNumber( sqrt(3)).rep == DMP([ QQ(1), QQ(0)], QQ) assert AlgebraicNumber(-sqrt(3)).rep == DMP([ QQ(1), QQ(0)], QQ) a = AlgebraicNumber(sqrt(2)) b = AlgebraicNumber(sqrt(2)) assert a == b c = AlgebraicNumber(sqrt(2), gen=x) assert a == b assert a == c a = AlgebraicNumber(sqrt(2), [1, 2]) b = AlgebraicNumber(sqrt(2), [1, 3]) assert a != b and a != sqrt(2) + 3 assert (a == x) is False and (a != x) is True a = AlgebraicNumber(sqrt(2), [1, 0]) b = AlgebraicNumber(sqrt(2), [1, 0], alias=y) assert a.as_poly(x) == Poly(x, domain='QQ') assert b.as_poly() == Poly(y, domain='QQ') assert a.as_expr() == sqrt(2) assert a.as_expr(x) == x assert b.as_expr() == sqrt(2) assert b.as_expr(x) == x a = AlgebraicNumber(sqrt(2), [2, 3]) b = AlgebraicNumber(sqrt(2), [2, 3], alias=y) p = a.as_poly() assert p == Poly(2*p.gen + 3) assert a.as_poly(x) == Poly(2*x + 3, domain='QQ') assert b.as_poly() == Poly(2*y + 3, domain='QQ') assert a.as_expr() == 2*sqrt(2) + 3 assert a.as_expr(x) == 2*x + 3 assert b.as_expr() == 2*sqrt(2) + 3 assert b.as_expr(x) == 2*x + 3 a = AlgebraicNumber(sqrt(2)) b = to_number_field(sqrt(2)) assert a.args == b.args == (sqrt(2), Tuple(1, 0)) b = AlgebraicNumber(sqrt(2), alias='alpha') assert b.args == (sqrt(2), Tuple(1, 0), Symbol('alpha')) a = AlgebraicNumber(sqrt(2), [1, 2, 3]) assert a.args == (sqrt(2), Tuple(1, 2, 3)) def test_to_algebraic_integer(): a = AlgebraicNumber(sqrt(3), gen=x).to_algebraic_integer() assert a.minpoly == x**2 - 3 assert a.root == sqrt(3) assert a.rep == DMP([QQ(1), QQ(0)], QQ) a = AlgebraicNumber(2*sqrt(3), gen=x).to_algebraic_integer() assert a.minpoly == x**2 - 12 assert a.root == 2*sqrt(3) assert a.rep == DMP([QQ(1), QQ(0)], QQ) a = AlgebraicNumber(sqrt(3)/2, gen=x).to_algebraic_integer() assert a.minpoly == x**2 - 12 assert a.root == 2*sqrt(3) assert a.rep == DMP([QQ(1), QQ(0)], QQ) a = AlgebraicNumber(sqrt(3)/2, [Rational(7, 19), 3], gen=x).to_algebraic_integer() assert a.minpoly == x**2 - 12 assert a.root == 2*sqrt(3) assert a.rep == DMP([QQ(7, 19), QQ(3)], QQ) def test_IntervalPrinter(): ip = IntervalPrinter() assert ip.doprint(x**Q(1, 3)) == "x**(mpi('1/3'))" assert ip.doprint(sqrt(x)) == "x**(mpi('1/2'))" def test_isolate(): assert isolate(1) == (1, 1) assert isolate(S.Half) == (S.Half, S.Half) assert isolate(sqrt(2)) == (1, 2) assert isolate(-sqrt(2)) == (-2, -1) assert isolate(sqrt(2), eps=Rational(1, 100)) == (Rational(24, 17), Rational(17, 12)) assert isolate(-sqrt(2), eps=Rational(1, 100)) == (Rational(-17, 12), Rational(-24, 17)) raises(NotImplementedError, lambda: isolate(I)) def test_minpoly_fraction_field(): assert minimal_polynomial(1/x, y) == -x*y + 1 assert minimal_polynomial(1 / (x + 1), y) == (x + 1)*y - 1 assert minimal_polynomial(sqrt(x), y) == y**2 - x assert minimal_polynomial(sqrt(x + 1), y) == y**2 - x - 1 assert minimal_polynomial(sqrt(x) / x, y) == x*y**2 - 1 assert minimal_polynomial(sqrt(2) * sqrt(x), y) == y**2 - 2 * x assert minimal_polynomial(sqrt(2) + sqrt(x), y) == \ y**4 + (-2*x - 4)*y**2 + x**2 - 4*x + 4 assert minimal_polynomial(x**Rational(1,3), y) == y**3 - x assert minimal_polynomial(x**Rational(1,3) + sqrt(x), y) == \ y**6 - 3*x*y**4 - 2*x*y**3 + 3*x**2*y**2 - 6*x**2*y - x**3 + x**2 assert minimal_polynomial(sqrt(x) / z, y) == z**2*y**2 - x assert minimal_polynomial(sqrt(x) / (z + 1), y) == (z**2 + 2*z + 1)*y**2 - x assert minimal_polynomial(1/x, y, polys=True) == Poly(-x*y + 1, y, domain='ZZ(x)') assert minimal_polynomial(1 / (x + 1), y, polys=True) == \ Poly((x + 1)*y - 1, y, domain='ZZ(x)') assert minimal_polynomial(sqrt(x), y, polys=True) == Poly(y**2 - x, y, domain='ZZ(x)') assert minimal_polynomial(sqrt(x) / z, y, polys=True) == \ Poly(z**2*y**2 - x, y, domain='ZZ(x, z)') # this is (sqrt(1 + x**3)/x).integrate(x).diff(x) - sqrt(1 + x**3)/x a = sqrt(x)/sqrt(1 + x**(-3)) - sqrt(x**3 + 1)/x + 1/(x**Rational(5, 2)* \ (1 + x**(-3))**Rational(3, 2)) + 1/(x**Rational(11, 2)*(1 + x**(-3))**Rational(3, 2)) assert minimal_polynomial(a, y) == y raises(NotAlgebraic, lambda: minimal_polynomial(exp(x), y)) raises(GeneratorsError, lambda: minimal_polynomial(sqrt(x), x)) raises(GeneratorsError, lambda: minimal_polynomial(sqrt(x) - y, x)) raises(NotImplementedError, lambda: minimal_polynomial(sqrt(x), y, compose=False)) @slow def test_minpoly_fraction_field_slow(): assert minimal_polynomial(minimal_polynomial(sqrt(x**Rational(1,5) - 1), y).subs(y, sqrt(x**Rational(1,5) - 1)), z) == z def test_minpoly_domain(): assert minimal_polynomial(sqrt(2), x, domain=QQ.algebraic_field(sqrt(2))) == \ x - sqrt(2) assert minimal_polynomial(sqrt(8), x, domain=QQ.algebraic_field(sqrt(2))) == \ x - 2*sqrt(2) assert minimal_polynomial(sqrt(Rational(3,2)), x, domain=QQ.algebraic_field(sqrt(2))) == 2*x**2 - 3 raises(NotAlgebraic, lambda: minimal_polynomial(y, x, domain=QQ)) def test_issue_14831(): a = -2*sqrt(2)*sqrt(12*sqrt(2) + 17) assert minimal_polynomial(a, x) == x**2 + 16*x - 8 e = (-3*sqrt(12*sqrt(2) + 17) + 12*sqrt(2) + 17 - 2*sqrt(2)*sqrt(12*sqrt(2) + 17)) assert minimal_polynomial(e, x) == x def test_issue_18248(): assert nonlinsolve([x*y**3-sqrt(2)/3, x*y**6-4/(9*(sqrt(3)))],x,y) == \ FiniteSet((sqrt(3)/2, sqrt(6)/3), (sqrt(3)/2, -sqrt(6)/6 - sqrt(2)*I/2), (sqrt(3)/2, -sqrt(6)/6 + sqrt(2)*I/2)) def test_issue_13230(): c1 = Circle(Point2D(3, sqrt(5)), 5) c2 = Circle(Point2D(4, sqrt(7)), 6) assert intersection(c1, c2) == [Point2D(-1 + (-sqrt(7) + sqrt(5))*(-2*sqrt(7)/29 + 9*sqrt(5)/29 + sqrt(196*sqrt(35) + 1941)/29), -2*sqrt(7)/29 + 9*sqrt(5)/29 + sqrt(196*sqrt(35) + 1941)/29), Point2D(-1 + (-sqrt(7) + sqrt(5))*(-sqrt(196*sqrt(35) + 1941)/29 - 2*sqrt(7)/29 + 9*sqrt(5)/29), -sqrt(196*sqrt(35) + 1941)/29 - 2*sqrt(7)/29 + 9*sqrt(5)/29)] def test_issue_19760(): e = 1/(sqrt(1 + sqrt(2)) - sqrt(2)*sqrt(1 + sqrt(2))) + 1 mp_expected = x**4 - 4*x**3 + 4*x**2 - 2 for comp in (True, False): mp = Poly(minimal_polynomial(e, compose=comp)) assert mp(x) == mp_expected, "minimal_polynomial(e, compose=%s) = %s; %s expected" % (comp, mp(x), mp_expected) def test_issue_20163(): assert apart(1/(x**6+1), extension=[sqrt(3), I]) == \ (sqrt(3) + I)/(2*x + sqrt(3) + I)/6 + \ (sqrt(3) - I)/(2*x + sqrt(3) - I)/6 - \ (sqrt(3) - I)/(2*x - sqrt(3) + I)/6 - \ (sqrt(3) + I)/(2*x - sqrt(3) - I)/6 + \ I/(x + I)/6 - I/(x - I)/6
76d2f40cfee3ea71ba0f34dc340b956b2b351c95effbccc5becf45d9f22b0d08
"""Tests for user-friendly public interface to polynomial functions. """ import pickle from sympy.polys.polytools import ( Poly, PurePoly, poly, parallel_poly_from_expr, degree, degree_list, total_degree, LC, LM, LT, pdiv, prem, pquo, pexquo, div, rem, quo, exquo, half_gcdex, gcdex, invert, subresultants, resultant, discriminant, terms_gcd, cofactors, gcd, gcd_list, lcm, lcm_list, trunc, monic, content, primitive, compose, decompose, sturm, gff_list, gff, sqf_norm, sqf_part, sqf_list, sqf, factor_list, factor, intervals, refine_root, count_roots, real_roots, nroots, ground_roots, nth_power_roots_poly, cancel, reduced, groebner, GroebnerBasis, is_zero_dimensional, _torational_factor_list, to_rational_coeffs) from sympy.polys.polyerrors import ( MultivariatePolynomialError, ExactQuotientFailed, PolificationFailed, ComputationFailed, UnificationFailed, RefinementFailed, GeneratorsNeeded, GeneratorsError, PolynomialError, CoercionFailed, DomainError, OptionError, FlagError) from sympy.polys.polyclasses import DMP from sympy.polys.fields import field from sympy.polys.domains import FF, ZZ, QQ, ZZ_I, QQ_I, RR, EX from sympy.polys.domains.realfield import RealField from sympy.polys.domains.complexfield import ComplexField from sympy.polys.orderings import lex, grlex, grevlex from sympy import ( S, Integer, Rational, Float, Mul, Symbol, sqrt, Piecewise, Derivative, exp, sin, tanh, expand, oo, I, pi, re, im, rootof, Eq, Tuple, Expr, diff) from sympy.core.add import Add from sympy.core.basic import _aresame from sympy.core.compatibility import iterable from sympy.core.mul import _keep_coeff from sympy.core.power import Pow from sympy.testing.pytest import raises, warns_deprecated_sympy from sympy.abc import a, b, c, d, p, q, t, w, x, y, z from sympy import MatrixSymbol, Matrix def _epsilon_eq(a, b): for u, v in zip(a, b): if abs(u - v) > 1e-10: return False return True def _strict_eq(a, b): if type(a) == type(b): if iterable(a): if len(a) == len(b): return all(_strict_eq(c, d) for c, d in zip(a, b)) else: return False else: return isinstance(a, Poly) and a.eq(b, strict=True) else: return False def test_Poly_mixed_operations(): p = Poly(x, x) with warns_deprecated_sympy(): p * exp(x) with warns_deprecated_sympy(): p + exp(x) with warns_deprecated_sympy(): p - exp(x) def test_Poly_from_dict(): K = FF(3) assert Poly.from_dict( {0: 1, 1: 2}, gens=x, domain=K).rep == DMP([K(2), K(1)], K) assert Poly.from_dict( {0: 1, 1: 5}, gens=x, domain=K).rep == DMP([K(2), K(1)], K) assert Poly.from_dict( {(0,): 1, (1,): 2}, gens=x, domain=K).rep == DMP([K(2), K(1)], K) assert Poly.from_dict( {(0,): 1, (1,): 5}, gens=x, domain=K).rep == DMP([K(2), K(1)], K) assert Poly.from_dict({(0, 0): 1, (1, 1): 2}, gens=( x, y), domain=K).rep == DMP([[K(2), K(0)], [K(1)]], K) assert Poly.from_dict({0: 1, 1: 2}, gens=x).rep == DMP([ZZ(2), ZZ(1)], ZZ) assert Poly.from_dict( {0: 1, 1: 2}, gens=x, field=True).rep == DMP([QQ(2), QQ(1)], QQ) assert Poly.from_dict( {0: 1, 1: 2}, gens=x, domain=ZZ).rep == DMP([ZZ(2), ZZ(1)], ZZ) assert Poly.from_dict( {0: 1, 1: 2}, gens=x, domain=QQ).rep == DMP([QQ(2), QQ(1)], QQ) assert Poly.from_dict( {(0,): 1, (1,): 2}, gens=x).rep == DMP([ZZ(2), ZZ(1)], ZZ) assert Poly.from_dict( {(0,): 1, (1,): 2}, gens=x, field=True).rep == DMP([QQ(2), QQ(1)], QQ) assert Poly.from_dict( {(0,): 1, (1,): 2}, gens=x, domain=ZZ).rep == DMP([ZZ(2), ZZ(1)], ZZ) assert Poly.from_dict( {(0,): 1, (1,): 2}, gens=x, domain=QQ).rep == DMP([QQ(2), QQ(1)], QQ) assert Poly.from_dict({(1,): sin(y)}, gens=x, composite=False) == \ Poly(sin(y)*x, x, domain='EX') assert Poly.from_dict({(1,): y}, gens=x, composite=False) == \ Poly(y*x, x, domain='EX') assert Poly.from_dict({(1, 1): 1}, gens=(x, y), composite=False) == \ Poly(x*y, x, y, domain='ZZ') assert Poly.from_dict({(1, 0): y}, gens=(x, z), composite=False) == \ Poly(y*x, x, z, domain='EX') def test_Poly_from_list(): K = FF(3) assert Poly.from_list([2, 1], gens=x, domain=K).rep == DMP([K(2), K(1)], K) assert Poly.from_list([5, 1], gens=x, domain=K).rep == DMP([K(2), K(1)], K) assert Poly.from_list([2, 1], gens=x).rep == DMP([ZZ(2), ZZ(1)], ZZ) assert Poly.from_list([2, 1], gens=x, field=True).rep == DMP([QQ(2), QQ(1)], QQ) assert Poly.from_list([2, 1], gens=x, domain=ZZ).rep == DMP([ZZ(2), ZZ(1)], ZZ) assert Poly.from_list([2, 1], gens=x, domain=QQ).rep == DMP([QQ(2), QQ(1)], QQ) assert Poly.from_list([0, 1.0], gens=x).rep == DMP([RR(1.0)], RR) assert Poly.from_list([1.0, 0], gens=x).rep == DMP([RR(1.0), RR(0.0)], RR) raises(MultivariatePolynomialError, lambda: Poly.from_list([[]], gens=(x, y))) def test_Poly_from_poly(): f = Poly(x + 7, x, domain=ZZ) g = Poly(x + 2, x, modulus=3) h = Poly(x + y, x, y, domain=ZZ) K = FF(3) assert Poly.from_poly(f) == f assert Poly.from_poly(f, domain=K).rep == DMP([K(1), K(1)], K) assert Poly.from_poly(f, domain=ZZ).rep == DMP([1, 7], ZZ) assert Poly.from_poly(f, domain=QQ).rep == DMP([1, 7], QQ) assert Poly.from_poly(f, gens=x) == f assert Poly.from_poly(f, gens=x, domain=K).rep == DMP([K(1), K(1)], K) assert Poly.from_poly(f, gens=x, domain=ZZ).rep == DMP([1, 7], ZZ) assert Poly.from_poly(f, gens=x, domain=QQ).rep == DMP([1, 7], QQ) assert Poly.from_poly(f, gens=y) == Poly(x + 7, y, domain='ZZ[x]') raises(CoercionFailed, lambda: Poly.from_poly(f, gens=y, domain=K)) raises(CoercionFailed, lambda: Poly.from_poly(f, gens=y, domain=ZZ)) raises(CoercionFailed, lambda: Poly.from_poly(f, gens=y, domain=QQ)) assert Poly.from_poly(f, gens=(x, y)) == Poly(x + 7, x, y, domain='ZZ') assert Poly.from_poly( f, gens=(x, y), domain=ZZ) == Poly(x + 7, x, y, domain='ZZ') assert Poly.from_poly( f, gens=(x, y), domain=QQ) == Poly(x + 7, x, y, domain='QQ') assert Poly.from_poly( f, gens=(x, y), modulus=3) == Poly(x + 7, x, y, domain='FF(3)') K = FF(2) assert Poly.from_poly(g) == g assert Poly.from_poly(g, domain=ZZ).rep == DMP([1, -1], ZZ) raises(CoercionFailed, lambda: Poly.from_poly(g, domain=QQ)) assert Poly.from_poly(g, domain=K).rep == DMP([K(1), K(0)], K) assert Poly.from_poly(g, gens=x) == g assert Poly.from_poly(g, gens=x, domain=ZZ).rep == DMP([1, -1], ZZ) raises(CoercionFailed, lambda: Poly.from_poly(g, gens=x, domain=QQ)) assert Poly.from_poly(g, gens=x, domain=K).rep == DMP([K(1), K(0)], K) K = FF(3) assert Poly.from_poly(h) == h assert Poly.from_poly( h, domain=ZZ).rep == DMP([[ZZ(1)], [ZZ(1), ZZ(0)]], ZZ) assert Poly.from_poly( h, domain=QQ).rep == DMP([[QQ(1)], [QQ(1), QQ(0)]], QQ) assert Poly.from_poly(h, domain=K).rep == DMP([[K(1)], [K(1), K(0)]], K) assert Poly.from_poly(h, gens=x) == Poly(x + y, x, domain=ZZ[y]) raises(CoercionFailed, lambda: Poly.from_poly(h, gens=x, domain=ZZ)) assert Poly.from_poly( h, gens=x, domain=ZZ[y]) == Poly(x + y, x, domain=ZZ[y]) raises(CoercionFailed, lambda: Poly.from_poly(h, gens=x, domain=QQ)) assert Poly.from_poly( h, gens=x, domain=QQ[y]) == Poly(x + y, x, domain=QQ[y]) raises(CoercionFailed, lambda: Poly.from_poly(h, gens=x, modulus=3)) assert Poly.from_poly(h, gens=y) == Poly(x + y, y, domain=ZZ[x]) raises(CoercionFailed, lambda: Poly.from_poly(h, gens=y, domain=ZZ)) assert Poly.from_poly( h, gens=y, domain=ZZ[x]) == Poly(x + y, y, domain=ZZ[x]) raises(CoercionFailed, lambda: Poly.from_poly(h, gens=y, domain=QQ)) assert Poly.from_poly( h, gens=y, domain=QQ[x]) == Poly(x + y, y, domain=QQ[x]) raises(CoercionFailed, lambda: Poly.from_poly(h, gens=y, modulus=3)) assert Poly.from_poly(h, gens=(x, y)) == h assert Poly.from_poly( h, gens=(x, y), domain=ZZ).rep == DMP([[ZZ(1)], [ZZ(1), ZZ(0)]], ZZ) assert Poly.from_poly( h, gens=(x, y), domain=QQ).rep == DMP([[QQ(1)], [QQ(1), QQ(0)]], QQ) assert Poly.from_poly( h, gens=(x, y), domain=K).rep == DMP([[K(1)], [K(1), K(0)]], K) assert Poly.from_poly( h, gens=(y, x)).rep == DMP([[ZZ(1)], [ZZ(1), ZZ(0)]], ZZ) assert Poly.from_poly( h, gens=(y, x), domain=ZZ).rep == DMP([[ZZ(1)], [ZZ(1), ZZ(0)]], ZZ) assert Poly.from_poly( h, gens=(y, x), domain=QQ).rep == DMP([[QQ(1)], [QQ(1), QQ(0)]], QQ) assert Poly.from_poly( h, gens=(y, x), domain=K).rep == DMP([[K(1)], [K(1), K(0)]], K) assert Poly.from_poly( h, gens=(x, y), field=True).rep == DMP([[QQ(1)], [QQ(1), QQ(0)]], QQ) assert Poly.from_poly( h, gens=(x, y), field=True).rep == DMP([[QQ(1)], [QQ(1), QQ(0)]], QQ) def test_Poly_from_expr(): raises(GeneratorsNeeded, lambda: Poly.from_expr(S.Zero)) raises(GeneratorsNeeded, lambda: Poly.from_expr(S(7))) F3 = FF(3) assert Poly.from_expr(x + 5, domain=F3).rep == DMP([F3(1), F3(2)], F3) assert Poly.from_expr(y + 5, domain=F3).rep == DMP([F3(1), F3(2)], F3) assert Poly.from_expr(x + 5, x, domain=F3).rep == DMP([F3(1), F3(2)], F3) assert Poly.from_expr(y + 5, y, domain=F3).rep == DMP([F3(1), F3(2)], F3) assert Poly.from_expr(x + y, domain=F3).rep == DMP([[F3(1)], [F3(1), F3(0)]], F3) assert Poly.from_expr(x + y, x, y, domain=F3).rep == DMP([[F3(1)], [F3(1), F3(0)]], F3) assert Poly.from_expr(x + 5).rep == DMP([1, 5], ZZ) assert Poly.from_expr(y + 5).rep == DMP([1, 5], ZZ) assert Poly.from_expr(x + 5, x).rep == DMP([1, 5], ZZ) assert Poly.from_expr(y + 5, y).rep == DMP([1, 5], ZZ) assert Poly.from_expr(x + 5, domain=ZZ).rep == DMP([1, 5], ZZ) assert Poly.from_expr(y + 5, domain=ZZ).rep == DMP([1, 5], ZZ) assert Poly.from_expr(x + 5, x, domain=ZZ).rep == DMP([1, 5], ZZ) assert Poly.from_expr(y + 5, y, domain=ZZ).rep == DMP([1, 5], ZZ) assert Poly.from_expr(x + 5, x, y, domain=ZZ).rep == DMP([[1], [5]], ZZ) assert Poly.from_expr(y + 5, x, y, domain=ZZ).rep == DMP([[1, 5]], ZZ) def test_poly_from_domain_element(): dom = ZZ[x] assert Poly(dom(x+1), y, domain=dom).rep == DMP([dom(x+1)], dom) dom = dom.get_field() assert Poly(dom(x+1), y, domain=dom).rep == DMP([dom(x+1)], dom) dom = QQ[x] assert Poly(dom(x+1), y, domain=dom).rep == DMP([dom(x+1)], dom) dom = dom.get_field() assert Poly(dom(x+1), y, domain=dom).rep == DMP([dom(x+1)], dom) dom = ZZ.old_poly_ring(x) assert Poly(dom([1, 1]), y, domain=dom).rep == DMP([dom([1, 1])], dom) dom = dom.get_field() assert Poly(dom([1, 1]), y, domain=dom).rep == DMP([dom([1, 1])], dom) dom = QQ.old_poly_ring(x) assert Poly(dom([1, 1]), y, domain=dom).rep == DMP([dom([1, 1])], dom) dom = dom.get_field() assert Poly(dom([1, 1]), y, domain=dom).rep == DMP([dom([1, 1])], dom) dom = QQ.algebraic_field(I) assert Poly(dom([1, 1]), x, domain=dom).rep == DMP([dom([1, 1])], dom) def test_Poly__new__(): raises(GeneratorsError, lambda: Poly(x + 1, x, x)) raises(GeneratorsError, lambda: Poly(x + y, x, y, domain=ZZ[x])) raises(GeneratorsError, lambda: Poly(x + y, x, y, domain=ZZ[y])) raises(OptionError, lambda: Poly(x, x, symmetric=True)) raises(OptionError, lambda: Poly(x + 2, x, modulus=3, domain=QQ)) raises(OptionError, lambda: Poly(x + 2, x, domain=ZZ, gaussian=True)) raises(OptionError, lambda: Poly(x + 2, x, modulus=3, gaussian=True)) raises(OptionError, lambda: Poly(x + 2, x, domain=ZZ, extension=[sqrt(3)])) raises(OptionError, lambda: Poly(x + 2, x, modulus=3, extension=[sqrt(3)])) raises(OptionError, lambda: Poly(x + 2, x, domain=ZZ, extension=True)) raises(OptionError, lambda: Poly(x + 2, x, modulus=3, extension=True)) raises(OptionError, lambda: Poly(x + 2, x, domain=ZZ, greedy=True)) raises(OptionError, lambda: Poly(x + 2, x, domain=QQ, field=True)) raises(OptionError, lambda: Poly(x + 2, x, domain=ZZ, greedy=False)) raises(OptionError, lambda: Poly(x + 2, x, domain=QQ, field=False)) raises(NotImplementedError, lambda: Poly(x + 1, x, modulus=3, order='grlex')) raises(NotImplementedError, lambda: Poly(x + 1, x, order='grlex')) raises(GeneratorsNeeded, lambda: Poly({1: 2, 0: 1})) raises(GeneratorsNeeded, lambda: Poly([2, 1])) raises(GeneratorsNeeded, lambda: Poly((2, 1))) raises(GeneratorsNeeded, lambda: Poly(1)) f = a*x**2 + b*x + c assert Poly({2: a, 1: b, 0: c}, x) == f assert Poly(iter([a, b, c]), x) == f assert Poly([a, b, c], x) == f assert Poly((a, b, c), x) == f f = Poly({}, x, y, z) assert f.gens == (x, y, z) and f.as_expr() == 0 assert Poly(Poly(a*x + b*y, x, y), x) == Poly(a*x + b*y, x) assert Poly(3*x**2 + 2*x + 1, domain='ZZ').all_coeffs() == [3, 2, 1] assert Poly(3*x**2 + 2*x + 1, domain='QQ').all_coeffs() == [3, 2, 1] assert Poly(3*x**2 + 2*x + 1, domain='RR').all_coeffs() == [3.0, 2.0, 1.0] raises(CoercionFailed, lambda: Poly(3*x**2/5 + x*Rational(2, 5) + 1, domain='ZZ')) assert Poly( 3*x**2/5 + x*Rational(2, 5) + 1, domain='QQ').all_coeffs() == [Rational(3, 5), Rational(2, 5), 1] assert _epsilon_eq( Poly(3*x**2/5 + x*Rational(2, 5) + 1, domain='RR').all_coeffs(), [0.6, 0.4, 1.0]) assert Poly(3.0*x**2 + 2.0*x + 1, domain='ZZ').all_coeffs() == [3, 2, 1] assert Poly(3.0*x**2 + 2.0*x + 1, domain='QQ').all_coeffs() == [3, 2, 1] assert Poly( 3.0*x**2 + 2.0*x + 1, domain='RR').all_coeffs() == [3.0, 2.0, 1.0] raises(CoercionFailed, lambda: Poly(3.1*x**2 + 2.1*x + 1, domain='ZZ')) assert Poly(3.1*x**2 + 2.1*x + 1, domain='QQ').all_coeffs() == [Rational(31, 10), Rational(21, 10), 1] assert Poly(3.1*x**2 + 2.1*x + 1, domain='RR').all_coeffs() == [3.1, 2.1, 1.0] assert Poly({(2, 1): 1, (1, 2): 2, (1, 1): 3}, x, y) == \ Poly(x**2*y + 2*x*y**2 + 3*x*y, x, y) assert Poly(x**2 + 1, extension=I).get_domain() == QQ.algebraic_field(I) f = 3*x**5 - x**4 + x**3 - x** 2 + 65538 assert Poly(f, x, modulus=65537, symmetric=True) == \ Poly(3*x**5 - x**4 + x**3 - x** 2 + 1, x, modulus=65537, symmetric=True) assert Poly(f, x, modulus=65537, symmetric=False) == \ Poly(3*x**5 + 65536*x**4 + x**3 + 65536*x** 2 + 1, x, modulus=65537, symmetric=False) assert isinstance(Poly(x**2 + x + 1.0).get_domain(), RealField) assert isinstance(Poly(x**2 + x + I + 1.0).get_domain(), ComplexField) def test_Poly__args(): assert Poly(x**2 + 1).args == (x**2 + 1, x) def test_Poly__gens(): assert Poly((x - p)*(x - q), x).gens == (x,) assert Poly((x - p)*(x - q), p).gens == (p,) assert Poly((x - p)*(x - q), q).gens == (q,) assert Poly((x - p)*(x - q), x, p).gens == (x, p) assert Poly((x - p)*(x - q), x, q).gens == (x, q) assert Poly((x - p)*(x - q), x, p, q).gens == (x, p, q) assert Poly((x - p)*(x - q), p, x, q).gens == (p, x, q) assert Poly((x - p)*(x - q), p, q, x).gens == (p, q, x) assert Poly((x - p)*(x - q)).gens == (x, p, q) assert Poly((x - p)*(x - q), sort='x > p > q').gens == (x, p, q) assert Poly((x - p)*(x - q), sort='p > x > q').gens == (p, x, q) assert Poly((x - p)*(x - q), sort='p > q > x').gens == (p, q, x) assert Poly((x - p)*(x - q), x, p, q, sort='p > q > x').gens == (x, p, q) assert Poly((x - p)*(x - q), wrt='x').gens == (x, p, q) assert Poly((x - p)*(x - q), wrt='p').gens == (p, x, q) assert Poly((x - p)*(x - q), wrt='q').gens == (q, x, p) assert Poly((x - p)*(x - q), wrt=x).gens == (x, p, q) assert Poly((x - p)*(x - q), wrt=p).gens == (p, x, q) assert Poly((x - p)*(x - q), wrt=q).gens == (q, x, p) assert Poly((x - p)*(x - q), x, p, q, wrt='p').gens == (x, p, q) assert Poly((x - p)*(x - q), wrt='p', sort='q > x').gens == (p, q, x) assert Poly((x - p)*(x - q), wrt='q', sort='p > x').gens == (q, p, x) def test_Poly_zero(): assert Poly(x).zero == Poly(0, x, domain=ZZ) assert Poly(x/2).zero == Poly(0, x, domain=QQ) def test_Poly_one(): assert Poly(x).one == Poly(1, x, domain=ZZ) assert Poly(x/2).one == Poly(1, x, domain=QQ) def test_Poly__unify(): raises(UnificationFailed, lambda: Poly(x)._unify(y)) F3 = FF(3) F5 = FF(5) assert Poly(x, x, modulus=3)._unify(Poly(y, y, modulus=3))[2:] == ( DMP([[F3(1)], []], F3), DMP([[F3(1), F3(0)]], F3)) assert Poly(x, x, modulus=3)._unify(Poly(y, y, modulus=5))[2:] == ( DMP([[F5(1)], []], F5), DMP([[F5(1), F5(0)]], F5)) assert Poly(y, x, y)._unify(Poly(x, x, modulus=3))[2:] == (DMP([[F3(1), F3(0)]], F3), DMP([[F3(1)], []], F3)) assert Poly(x, x, modulus=3)._unify(Poly(y, x, y))[2:] == (DMP([[F3(1)], []], F3), DMP([[F3(1), F3(0)]], F3)) assert Poly(x + 1, x)._unify(Poly(x + 2, x))[2:] == (DMP([1, 1], ZZ), DMP([1, 2], ZZ)) assert Poly(x + 1, x, domain='QQ')._unify(Poly(x + 2, x))[2:] == (DMP([1, 1], QQ), DMP([1, 2], QQ)) assert Poly(x + 1, x)._unify(Poly(x + 2, x, domain='QQ'))[2:] == (DMP([1, 1], QQ), DMP([1, 2], QQ)) assert Poly(x + 1, x)._unify(Poly(x + 2, x, y))[2:] == (DMP([[1], [1]], ZZ), DMP([[1], [2]], ZZ)) assert Poly(x + 1, x, domain='QQ')._unify(Poly(x + 2, x, y))[2:] == (DMP([[1], [1]], QQ), DMP([[1], [2]], QQ)) assert Poly(x + 1, x)._unify(Poly(x + 2, x, y, domain='QQ'))[2:] == (DMP([[1], [1]], QQ), DMP([[1], [2]], QQ)) assert Poly(x + 1, x, y)._unify(Poly(x + 2, x))[2:] == (DMP([[1], [1]], ZZ), DMP([[1], [2]], ZZ)) assert Poly(x + 1, x, y, domain='QQ')._unify(Poly(x + 2, x))[2:] == (DMP([[1], [1]], QQ), DMP([[1], [2]], QQ)) assert Poly(x + 1, x, y)._unify(Poly(x + 2, x, domain='QQ'))[2:] == (DMP([[1], [1]], QQ), DMP([[1], [2]], QQ)) assert Poly(x + 1, x, y)._unify(Poly(x + 2, x, y))[2:] == (DMP([[1], [1]], ZZ), DMP([[1], [2]], ZZ)) assert Poly(x + 1, x, y, domain='QQ')._unify(Poly(x + 2, x, y))[2:] == (DMP([[1], [1]], QQ), DMP([[1], [2]], QQ)) assert Poly(x + 1, x, y)._unify(Poly(x + 2, x, y, domain='QQ'))[2:] == (DMP([[1], [1]], QQ), DMP([[1], [2]], QQ)) assert Poly(x + 1, x)._unify(Poly(x + 2, y, x))[2:] == (DMP([[1, 1]], ZZ), DMP([[1, 2]], ZZ)) assert Poly(x + 1, x, domain='QQ')._unify(Poly(x + 2, y, x))[2:] == (DMP([[1, 1]], QQ), DMP([[1, 2]], QQ)) assert Poly(x + 1, x)._unify(Poly(x + 2, y, x, domain='QQ'))[2:] == (DMP([[1, 1]], QQ), DMP([[1, 2]], QQ)) assert Poly(x + 1, y, x)._unify(Poly(x + 2, x))[2:] == (DMP([[1, 1]], ZZ), DMP([[1, 2]], ZZ)) assert Poly(x + 1, y, x, domain='QQ')._unify(Poly(x + 2, x))[2:] == (DMP([[1, 1]], QQ), DMP([[1, 2]], QQ)) assert Poly(x + 1, y, x)._unify(Poly(x + 2, x, domain='QQ'))[2:] == (DMP([[1, 1]], QQ), DMP([[1, 2]], QQ)) assert Poly(x + 1, x, y)._unify(Poly(x + 2, y, x))[2:] == (DMP([[1], [1]], ZZ), DMP([[1], [2]], ZZ)) assert Poly(x + 1, x, y, domain='QQ')._unify(Poly(x + 2, y, x))[2:] == (DMP([[1], [1]], QQ), DMP([[1], [2]], QQ)) assert Poly(x + 1, x, y)._unify(Poly(x + 2, y, x, domain='QQ'))[2:] == (DMP([[1], [1]], QQ), DMP([[1], [2]], QQ)) assert Poly(x + 1, y, x)._unify(Poly(x + 2, x, y))[2:] == (DMP([[1, 1]], ZZ), DMP([[1, 2]], ZZ)) assert Poly(x + 1, y, x, domain='QQ')._unify(Poly(x + 2, x, y))[2:] == (DMP([[1, 1]], QQ), DMP([[1, 2]], QQ)) assert Poly(x + 1, y, x)._unify(Poly(x + 2, x, y, domain='QQ'))[2:] == (DMP([[1, 1]], QQ), DMP([[1, 2]], QQ)) assert Poly(x**2 + I, x, domain=ZZ_I).unify(Poly(x**2 + sqrt(2), x, extension=True)) == \ (Poly(x**2 + I, x, domain='QQ<sqrt(2) + I>'), Poly(x**2 + sqrt(2), x, domain='QQ<sqrt(2) + I>')) F, A, B = field("a,b", ZZ) assert Poly(a*x, x, domain='ZZ[a]')._unify(Poly(a*b*x, x, domain='ZZ(a,b)'))[2:] == \ (DMP([A, F(0)], F.to_domain()), DMP([A*B, F(0)], F.to_domain())) assert Poly(a*x, x, domain='ZZ(a)')._unify(Poly(a*b*x, x, domain='ZZ(a,b)'))[2:] == \ (DMP([A, F(0)], F.to_domain()), DMP([A*B, F(0)], F.to_domain())) raises(CoercionFailed, lambda: Poly(Poly(x**2 + x**2*z, y, field=True), domain='ZZ(x)')) f = Poly(t**2 + t/3 + x, t, domain='QQ(x)') g = Poly(t**2 + t/3 + x, t, domain='QQ[x]') assert f._unify(g)[2:] == (f.rep, f.rep) def test_Poly_free_symbols(): assert Poly(x**2 + 1).free_symbols == {x} assert Poly(x**2 + y*z).free_symbols == {x, y, z} assert Poly(x**2 + y*z, x).free_symbols == {x, y, z} assert Poly(x**2 + sin(y*z)).free_symbols == {x, y, z} assert Poly(x**2 + sin(y*z), x).free_symbols == {x, y, z} assert Poly(x**2 + sin(y*z), x, domain=EX).free_symbols == {x, y, z} assert Poly(1 + x + x**2, x, y, z).free_symbols == {x} assert Poly(x + sin(y), z).free_symbols == {x, y} def test_PurePoly_free_symbols(): assert PurePoly(x**2 + 1).free_symbols == set() assert PurePoly(x**2 + y*z).free_symbols == set() assert PurePoly(x**2 + y*z, x).free_symbols == {y, z} assert PurePoly(x**2 + sin(y*z)).free_symbols == set() assert PurePoly(x**2 + sin(y*z), x).free_symbols == {y, z} assert PurePoly(x**2 + sin(y*z), x, domain=EX).free_symbols == {y, z} def test_Poly__eq__(): assert (Poly(x, x) == Poly(x, x)) is True assert (Poly(x, x, domain=QQ) == Poly(x, x)) is False assert (Poly(x, x) == Poly(x, x, domain=QQ)) is False assert (Poly(x, x, domain=ZZ[a]) == Poly(x, x)) is False assert (Poly(x, x) == Poly(x, x, domain=ZZ[a])) is False assert (Poly(x*y, x, y) == Poly(x, x)) is False assert (Poly(x, x, y) == Poly(x, x)) is False assert (Poly(x, x) == Poly(x, x, y)) is False assert (Poly(x**2 + 1, x) == Poly(y**2 + 1, y)) is False assert (Poly(y**2 + 1, y) == Poly(x**2 + 1, x)) is False f = Poly(x, x, domain=ZZ) g = Poly(x, x, domain=QQ) assert f.eq(g) is False assert f.ne(g) is True assert f.eq(g, strict=True) is False assert f.ne(g, strict=True) is True t0 = Symbol('t0') f = Poly((t0/2 + x**2)*t**2 - x**2*t, t, domain='QQ[x,t0]') g = Poly((t0/2 + x**2)*t**2 - x**2*t, t, domain='ZZ(x,t0)') assert (f == g) is False def test_PurePoly__eq__(): assert (PurePoly(x, x) == PurePoly(x, x)) is True assert (PurePoly(x, x, domain=QQ) == PurePoly(x, x)) is True assert (PurePoly(x, x) == PurePoly(x, x, domain=QQ)) is True assert (PurePoly(x, x, domain=ZZ[a]) == PurePoly(x, x)) is True assert (PurePoly(x, x) == PurePoly(x, x, domain=ZZ[a])) is True assert (PurePoly(x*y, x, y) == PurePoly(x, x)) is False assert (PurePoly(x, x, y) == PurePoly(x, x)) is False assert (PurePoly(x, x) == PurePoly(x, x, y)) is False assert (PurePoly(x**2 + 1, x) == PurePoly(y**2 + 1, y)) is True assert (PurePoly(y**2 + 1, y) == PurePoly(x**2 + 1, x)) is True f = PurePoly(x, x, domain=ZZ) g = PurePoly(x, x, domain=QQ) assert f.eq(g) is True assert f.ne(g) is False assert f.eq(g, strict=True) is False assert f.ne(g, strict=True) is True f = PurePoly(x, x, domain=ZZ) g = PurePoly(y, y, domain=QQ) assert f.eq(g) is True assert f.ne(g) is False assert f.eq(g, strict=True) is False assert f.ne(g, strict=True) is True def test_PurePoly_Poly(): assert isinstance(PurePoly(Poly(x**2 + 1)), PurePoly) is True assert isinstance(Poly(PurePoly(x**2 + 1)), Poly) is True def test_Poly_get_domain(): assert Poly(2*x).get_domain() == ZZ assert Poly(2*x, domain='ZZ').get_domain() == ZZ assert Poly(2*x, domain='QQ').get_domain() == QQ assert Poly(x/2).get_domain() == QQ raises(CoercionFailed, lambda: Poly(x/2, domain='ZZ')) assert Poly(x/2, domain='QQ').get_domain() == QQ assert isinstance(Poly(0.2*x).get_domain(), RealField) def test_Poly_set_domain(): assert Poly(2*x + 1).set_domain(ZZ) == Poly(2*x + 1) assert Poly(2*x + 1).set_domain('ZZ') == Poly(2*x + 1) assert Poly(2*x + 1).set_domain(QQ) == Poly(2*x + 1, domain='QQ') assert Poly(2*x + 1).set_domain('QQ') == Poly(2*x + 1, domain='QQ') assert Poly(Rational(2, 10)*x + Rational(1, 10)).set_domain('RR') == Poly(0.2*x + 0.1) assert Poly(0.2*x + 0.1).set_domain('QQ') == Poly(Rational(2, 10)*x + Rational(1, 10)) raises(CoercionFailed, lambda: Poly(x/2 + 1).set_domain(ZZ)) raises(CoercionFailed, lambda: Poly(x + 1, modulus=2).set_domain(QQ)) raises(GeneratorsError, lambda: Poly(x*y, x, y).set_domain(ZZ[y])) def test_Poly_get_modulus(): assert Poly(x**2 + 1, modulus=2).get_modulus() == 2 raises(PolynomialError, lambda: Poly(x**2 + 1).get_modulus()) def test_Poly_set_modulus(): assert Poly( x**2 + 1, modulus=2).set_modulus(7) == Poly(x**2 + 1, modulus=7) assert Poly( x**2 + 5, modulus=7).set_modulus(2) == Poly(x**2 + 1, modulus=2) assert Poly(x**2 + 1).set_modulus(2) == Poly(x**2 + 1, modulus=2) raises(CoercionFailed, lambda: Poly(x/2 + 1).set_modulus(2)) def test_Poly_add_ground(): assert Poly(x + 1).add_ground(2) == Poly(x + 3) def test_Poly_sub_ground(): assert Poly(x + 1).sub_ground(2) == Poly(x - 1) def test_Poly_mul_ground(): assert Poly(x + 1).mul_ground(2) == Poly(2*x + 2) def test_Poly_quo_ground(): assert Poly(2*x + 4).quo_ground(2) == Poly(x + 2) assert Poly(2*x + 3).quo_ground(2) == Poly(x + 1) def test_Poly_exquo_ground(): assert Poly(2*x + 4).exquo_ground(2) == Poly(x + 2) raises(ExactQuotientFailed, lambda: Poly(2*x + 3).exquo_ground(2)) def test_Poly_abs(): assert Poly(-x + 1, x).abs() == abs(Poly(-x + 1, x)) == Poly(x + 1, x) def test_Poly_neg(): assert Poly(-x + 1, x).neg() == -Poly(-x + 1, x) == Poly(x - 1, x) def test_Poly_add(): assert Poly(0, x).add(Poly(0, x)) == Poly(0, x) assert Poly(0, x) + Poly(0, x) == Poly(0, x) assert Poly(1, x).add(Poly(0, x)) == Poly(1, x) assert Poly(1, x, y) + Poly(0, x) == Poly(1, x, y) assert Poly(0, x).add(Poly(1, x, y)) == Poly(1, x, y) assert Poly(0, x, y) + Poly(1, x, y) == Poly(1, x, y) assert Poly(1, x) + x == Poly(x + 1, x) with warns_deprecated_sympy(): Poly(1, x) + sin(x) assert Poly(x, x) + 1 == Poly(x + 1, x) assert 1 + Poly(x, x) == Poly(x + 1, x) def test_Poly_sub(): assert Poly(0, x).sub(Poly(0, x)) == Poly(0, x) assert Poly(0, x) - Poly(0, x) == Poly(0, x) assert Poly(1, x).sub(Poly(0, x)) == Poly(1, x) assert Poly(1, x, y) - Poly(0, x) == Poly(1, x, y) assert Poly(0, x).sub(Poly(1, x, y)) == Poly(-1, x, y) assert Poly(0, x, y) - Poly(1, x, y) == Poly(-1, x, y) assert Poly(1, x) - x == Poly(1 - x, x) with warns_deprecated_sympy(): Poly(1, x) - sin(x) assert Poly(x, x) - 1 == Poly(x - 1, x) assert 1 - Poly(x, x) == Poly(1 - x, x) def test_Poly_mul(): assert Poly(0, x).mul(Poly(0, x)) == Poly(0, x) assert Poly(0, x) * Poly(0, x) == Poly(0, x) assert Poly(2, x).mul(Poly(4, x)) == Poly(8, x) assert Poly(2, x, y) * Poly(4, x) == Poly(8, x, y) assert Poly(4, x).mul(Poly(2, x, y)) == Poly(8, x, y) assert Poly(4, x, y) * Poly(2, x, y) == Poly(8, x, y) assert Poly(1, x) * x == Poly(x, x) with warns_deprecated_sympy(): Poly(1, x) * sin(x) assert Poly(x, x) * 2 == Poly(2*x, x) assert 2 * Poly(x, x) == Poly(2*x, x) def test_issue_13079(): assert Poly(x)*x == Poly(x**2, x, domain='ZZ') assert x*Poly(x) == Poly(x**2, x, domain='ZZ') assert -2*Poly(x) == Poly(-2*x, x, domain='ZZ') assert S(-2)*Poly(x) == Poly(-2*x, x, domain='ZZ') assert Poly(x)*S(-2) == Poly(-2*x, x, domain='ZZ') def test_Poly_sqr(): assert Poly(x*y, x, y).sqr() == Poly(x**2*y**2, x, y) def test_Poly_pow(): assert Poly(x, x).pow(10) == Poly(x**10, x) assert Poly(x, x).pow(Integer(10)) == Poly(x**10, x) assert Poly(2*y, x, y).pow(4) == Poly(16*y**4, x, y) assert Poly(2*y, x, y).pow(Integer(4)) == Poly(16*y**4, x, y) assert Poly(7*x*y, x, y)**3 == Poly(343*x**3*y**3, x, y) raises(TypeError, lambda: Poly(x*y + 1, x, y)**(-1)) raises(TypeError, lambda: Poly(x*y + 1, x, y)**x) def test_Poly_divmod(): f, g = Poly(x**2), Poly(x) q, r = g, Poly(0, x) assert divmod(f, g) == (q, r) assert f // g == q assert f % g == r assert divmod(f, x) == (q, r) assert f // x == q assert f % x == r q, r = Poly(0, x), Poly(2, x) assert divmod(2, g) == (q, r) assert 2 // g == q assert 2 % g == r assert Poly(x)/Poly(x) == 1 assert Poly(x**2)/Poly(x) == x assert Poly(x)/Poly(x**2) == 1/x def test_Poly_eq_ne(): assert (Poly(x + y, x, y) == Poly(x + y, x, y)) is True assert (Poly(x + y, x) == Poly(x + y, x, y)) is False assert (Poly(x + y, x, y) == Poly(x + y, x)) is False assert (Poly(x + y, x) == Poly(x + y, x)) is True assert (Poly(x + y, y) == Poly(x + y, y)) is True assert (Poly(x + y, x, y) == x + y) is True assert (Poly(x + y, x) == x + y) is True assert (Poly(x + y, x, y) == x + y) is True assert (Poly(x + y, x) == x + y) is True assert (Poly(x + y, y) == x + y) is True assert (Poly(x + y, x, y) != Poly(x + y, x, y)) is False assert (Poly(x + y, x) != Poly(x + y, x, y)) is True assert (Poly(x + y, x, y) != Poly(x + y, x)) is True assert (Poly(x + y, x) != Poly(x + y, x)) is False assert (Poly(x + y, y) != Poly(x + y, y)) is False assert (Poly(x + y, x, y) != x + y) is False assert (Poly(x + y, x) != x + y) is False assert (Poly(x + y, x, y) != x + y) is False assert (Poly(x + y, x) != x + y) is False assert (Poly(x + y, y) != x + y) is False assert (Poly(x, x) == sin(x)) is False assert (Poly(x, x) != sin(x)) is True def test_Poly_nonzero(): assert not bool(Poly(0, x)) is True assert not bool(Poly(1, x)) is False def test_Poly_properties(): assert Poly(0, x).is_zero is True assert Poly(1, x).is_zero is False assert Poly(1, x).is_one is True assert Poly(2, x).is_one is False assert Poly(x - 1, x).is_sqf is True assert Poly((x - 1)**2, x).is_sqf is False assert Poly(x - 1, x).is_monic is True assert Poly(2*x - 1, x).is_monic is False assert Poly(3*x + 2, x).is_primitive is True assert Poly(4*x + 2, x).is_primitive is False assert Poly(1, x).is_ground is True assert Poly(x, x).is_ground is False assert Poly(x + y + z + 1).is_linear is True assert Poly(x*y*z + 1).is_linear is False assert Poly(x*y + z + 1).is_quadratic is True assert Poly(x*y*z + 1).is_quadratic is False assert Poly(x*y).is_monomial is True assert Poly(x*y + 1).is_monomial is False assert Poly(x**2 + x*y).is_homogeneous is True assert Poly(x**3 + x*y).is_homogeneous is False assert Poly(x).is_univariate is True assert Poly(x*y).is_univariate is False assert Poly(x*y).is_multivariate is True assert Poly(x).is_multivariate is False assert Poly( x**16 + x**14 - x**10 + x**8 - x**6 + x**2 + 1).is_cyclotomic is False assert Poly( x**16 + x**14 - x**10 - x**8 - x**6 + x**2 + 1).is_cyclotomic is True def test_Poly_is_irreducible(): assert Poly(x**2 + x + 1).is_irreducible is True assert Poly(x**2 + 2*x + 1).is_irreducible is False assert Poly(7*x + 3, modulus=11).is_irreducible is True assert Poly(7*x**2 + 3*x + 1, modulus=11).is_irreducible is False def test_Poly_subs(): assert Poly(x + 1).subs(x, 0) == 1 assert Poly(x + 1).subs(x, x) == Poly(x + 1) assert Poly(x + 1).subs(x, y) == Poly(y + 1) assert Poly(x*y, x).subs(y, x) == x**2 assert Poly(x*y, x).subs(x, y) == y**2 def test_Poly_replace(): assert Poly(x + 1).replace(x) == Poly(x + 1) assert Poly(x + 1).replace(y) == Poly(y + 1) raises(PolynomialError, lambda: Poly(x + y).replace(z)) assert Poly(x + 1).replace(x, x) == Poly(x + 1) assert Poly(x + 1).replace(x, y) == Poly(y + 1) assert Poly(x + y).replace(x, x) == Poly(x + y) assert Poly(x + y).replace(x, z) == Poly(z + y, z, y) assert Poly(x + y).replace(y, y) == Poly(x + y) assert Poly(x + y).replace(y, z) == Poly(x + z, x, z) assert Poly(x + y).replace(z, t) == Poly(x + y) raises(PolynomialError, lambda: Poly(x + y).replace(x, y)) assert Poly(x + y, x).replace(x, z) == Poly(z + y, z) assert Poly(x + y, y).replace(y, z) == Poly(x + z, z) raises(PolynomialError, lambda: Poly(x + y, x).replace(x, y)) raises(PolynomialError, lambda: Poly(x + y, y).replace(y, x)) def test_Poly_reorder(): raises(PolynomialError, lambda: Poly(x + y).reorder(x, z)) assert Poly(x + y, x, y).reorder(x, y) == Poly(x + y, x, y) assert Poly(x + y, x, y).reorder(y, x) == Poly(x + y, y, x) assert Poly(x + y, y, x).reorder(x, y) == Poly(x + y, x, y) assert Poly(x + y, y, x).reorder(y, x) == Poly(x + y, y, x) assert Poly(x + y, x, y).reorder(wrt=x) == Poly(x + y, x, y) assert Poly(x + y, x, y).reorder(wrt=y) == Poly(x + y, y, x) def test_Poly_ltrim(): f = Poly(y**2 + y*z**2, x, y, z).ltrim(y) assert f.as_expr() == y**2 + y*z**2 and f.gens == (y, z) assert Poly(x*y - x, z, x, y).ltrim(1) == Poly(x*y - x, x, y) raises(PolynomialError, lambda: Poly(x*y**2 + y**2, x, y).ltrim(y)) raises(PolynomialError, lambda: Poly(x*y - x, x, y).ltrim(-1)) def test_Poly_has_only_gens(): assert Poly(x*y + 1, x, y, z).has_only_gens(x, y) is True assert Poly(x*y + z, x, y, z).has_only_gens(x, y) is False raises(GeneratorsError, lambda: Poly(x*y**2 + y**2, x, y).has_only_gens(t)) def test_Poly_to_ring(): assert Poly(2*x + 1, domain='ZZ').to_ring() == Poly(2*x + 1, domain='ZZ') assert Poly(2*x + 1, domain='QQ').to_ring() == Poly(2*x + 1, domain='ZZ') raises(CoercionFailed, lambda: Poly(x/2 + 1).to_ring()) raises(DomainError, lambda: Poly(2*x + 1, modulus=3).to_ring()) def test_Poly_to_field(): assert Poly(2*x + 1, domain='ZZ').to_field() == Poly(2*x + 1, domain='QQ') assert Poly(2*x + 1, domain='QQ').to_field() == Poly(2*x + 1, domain='QQ') assert Poly(x/2 + 1, domain='QQ').to_field() == Poly(x/2 + 1, domain='QQ') assert Poly(2*x + 1, modulus=3).to_field() == Poly(2*x + 1, modulus=3) assert Poly(2.0*x + 1.0).to_field() == Poly(2.0*x + 1.0) def test_Poly_to_exact(): assert Poly(2*x).to_exact() == Poly(2*x) assert Poly(x/2).to_exact() == Poly(x/2) assert Poly(0.1*x).to_exact() == Poly(x/10) def test_Poly_retract(): f = Poly(x**2 + 1, x, domain=QQ[y]) assert f.retract() == Poly(x**2 + 1, x, domain='ZZ') assert f.retract(field=True) == Poly(x**2 + 1, x, domain='QQ') assert Poly(0, x, y).retract() == Poly(0, x, y) def test_Poly_slice(): f = Poly(x**3 + 2*x**2 + 3*x + 4) assert f.slice(0, 0) == Poly(0, x) assert f.slice(0, 1) == Poly(4, x) assert f.slice(0, 2) == Poly(3*x + 4, x) assert f.slice(0, 3) == Poly(2*x**2 + 3*x + 4, x) assert f.slice(0, 4) == Poly(x**3 + 2*x**2 + 3*x + 4, x) assert f.slice(x, 0, 0) == Poly(0, x) assert f.slice(x, 0, 1) == Poly(4, x) assert f.slice(x, 0, 2) == Poly(3*x + 4, x) assert f.slice(x, 0, 3) == Poly(2*x**2 + 3*x + 4, x) assert f.slice(x, 0, 4) == Poly(x**3 + 2*x**2 + 3*x + 4, x) def test_Poly_coeffs(): assert Poly(0, x).coeffs() == [0] assert Poly(1, x).coeffs() == [1] assert Poly(2*x + 1, x).coeffs() == [2, 1] assert Poly(7*x**2 + 2*x + 1, x).coeffs() == [7, 2, 1] assert Poly(7*x**4 + 2*x + 1, x).coeffs() == [7, 2, 1] assert Poly(x*y**7 + 2*x**2*y**3).coeffs('lex') == [2, 1] assert Poly(x*y**7 + 2*x**2*y**3).coeffs('grlex') == [1, 2] def test_Poly_monoms(): assert Poly(0, x).monoms() == [(0,)] assert Poly(1, x).monoms() == [(0,)] assert Poly(2*x + 1, x).monoms() == [(1,), (0,)] assert Poly(7*x**2 + 2*x + 1, x).monoms() == [(2,), (1,), (0,)] assert Poly(7*x**4 + 2*x + 1, x).monoms() == [(4,), (1,), (0,)] assert Poly(x*y**7 + 2*x**2*y**3).monoms('lex') == [(2, 3), (1, 7)] assert Poly(x*y**7 + 2*x**2*y**3).monoms('grlex') == [(1, 7), (2, 3)] def test_Poly_terms(): assert Poly(0, x).terms() == [((0,), 0)] assert Poly(1, x).terms() == [((0,), 1)] assert Poly(2*x + 1, x).terms() == [((1,), 2), ((0,), 1)] assert Poly(7*x**2 + 2*x + 1, x).terms() == [((2,), 7), ((1,), 2), ((0,), 1)] assert Poly(7*x**4 + 2*x + 1, x).terms() == [((4,), 7), ((1,), 2), ((0,), 1)] assert Poly( x*y**7 + 2*x**2*y**3).terms('lex') == [((2, 3), 2), ((1, 7), 1)] assert Poly( x*y**7 + 2*x**2*y**3).terms('grlex') == [((1, 7), 1), ((2, 3), 2)] def test_Poly_all_coeffs(): assert Poly(0, x).all_coeffs() == [0] assert Poly(1, x).all_coeffs() == [1] assert Poly(2*x + 1, x).all_coeffs() == [2, 1] assert Poly(7*x**2 + 2*x + 1, x).all_coeffs() == [7, 2, 1] assert Poly(7*x**4 + 2*x + 1, x).all_coeffs() == [7, 0, 0, 2, 1] def test_Poly_all_monoms(): assert Poly(0, x).all_monoms() == [(0,)] assert Poly(1, x).all_monoms() == [(0,)] assert Poly(2*x + 1, x).all_monoms() == [(1,), (0,)] assert Poly(7*x**2 + 2*x + 1, x).all_monoms() == [(2,), (1,), (0,)] assert Poly(7*x**4 + 2*x + 1, x).all_monoms() == [(4,), (3,), (2,), (1,), (0,)] def test_Poly_all_terms(): assert Poly(0, x).all_terms() == [((0,), 0)] assert Poly(1, x).all_terms() == [((0,), 1)] assert Poly(2*x + 1, x).all_terms() == [((1,), 2), ((0,), 1)] assert Poly(7*x**2 + 2*x + 1, x).all_terms() == \ [((2,), 7), ((1,), 2), ((0,), 1)] assert Poly(7*x**4 + 2*x + 1, x).all_terms() == \ [((4,), 7), ((3,), 0), ((2,), 0), ((1,), 2), ((0,), 1)] def test_Poly_termwise(): f = Poly(x**2 + 20*x + 400) g = Poly(x**2 + 2*x + 4) def func(monom, coeff): (k,) = monom return coeff//10**(2 - k) assert f.termwise(func) == g def func(monom, coeff): (k,) = monom return (k,), coeff//10**(2 - k) assert f.termwise(func) == g def test_Poly_length(): assert Poly(0, x).length() == 0 assert Poly(1, x).length() == 1 assert Poly(x, x).length() == 1 assert Poly(x + 1, x).length() == 2 assert Poly(x**2 + 1, x).length() == 2 assert Poly(x**2 + x + 1, x).length() == 3 def test_Poly_as_dict(): assert Poly(0, x).as_dict() == {} assert Poly(0, x, y, z).as_dict() == {} assert Poly(1, x).as_dict() == {(0,): 1} assert Poly(1, x, y, z).as_dict() == {(0, 0, 0): 1} assert Poly(x**2 + 3, x).as_dict() == {(2,): 1, (0,): 3} assert Poly(x**2 + 3, x, y, z).as_dict() == {(2, 0, 0): 1, (0, 0, 0): 3} assert Poly(3*x**2*y*z**3 + 4*x*y + 5*x*z).as_dict() == {(2, 1, 3): 3, (1, 1, 0): 4, (1, 0, 1): 5} def test_Poly_as_expr(): assert Poly(0, x).as_expr() == 0 assert Poly(0, x, y, z).as_expr() == 0 assert Poly(1, x).as_expr() == 1 assert Poly(1, x, y, z).as_expr() == 1 assert Poly(x**2 + 3, x).as_expr() == x**2 + 3 assert Poly(x**2 + 3, x, y, z).as_expr() == x**2 + 3 assert Poly( 3*x**2*y*z**3 + 4*x*y + 5*x*z).as_expr() == 3*x**2*y*z**3 + 4*x*y + 5*x*z f = Poly(x**2 + 2*x*y**2 - y, x, y) assert f.as_expr() == -y + x**2 + 2*x*y**2 assert f.as_expr({x: 5}) == 25 - y + 10*y**2 assert f.as_expr({y: 6}) == -6 + 72*x + x**2 assert f.as_expr({x: 5, y: 6}) == 379 assert f.as_expr(5, 6) == 379 raises(GeneratorsError, lambda: f.as_expr({z: 7})) def test_Poly_lift(): assert Poly(x**4 - I*x + 17*I, x, gaussian=True).lift() == \ Poly(x**16 + 2*x**10 + 578*x**8 + x**4 - 578*x**2 + 83521, x, domain='QQ') def test_Poly_deflate(): assert Poly(0, x).deflate() == ((1,), Poly(0, x)) assert Poly(1, x).deflate() == ((1,), Poly(1, x)) assert Poly(x, x).deflate() == ((1,), Poly(x, x)) assert Poly(x**2, x).deflate() == ((2,), Poly(x, x)) assert Poly(x**17, x).deflate() == ((17,), Poly(x, x)) assert Poly( x**2*y*z**11 + x**4*z**11).deflate() == ((2, 1, 11), Poly(x*y*z + x**2*z)) def test_Poly_inject(): f = Poly(x**2*y + x*y**3 + x*y + 1, x) assert f.inject() == Poly(x**2*y + x*y**3 + x*y + 1, x, y) assert f.inject(front=True) == Poly(y**3*x + y*x**2 + y*x + 1, y, x) def test_Poly_eject(): f = Poly(x**2*y + x*y**3 + x*y + 1, x, y) assert f.eject(x) == Poly(x*y**3 + (x**2 + x)*y + 1, y, domain='ZZ[x]') assert f.eject(y) == Poly(y*x**2 + (y**3 + y)*x + 1, x, domain='ZZ[y]') ex = x + y + z + t + w g = Poly(ex, x, y, z, t, w) assert g.eject(x) == Poly(ex, y, z, t, w, domain='ZZ[x]') assert g.eject(x, y) == Poly(ex, z, t, w, domain='ZZ[x, y]') assert g.eject(x, y, z) == Poly(ex, t, w, domain='ZZ[x, y, z]') assert g.eject(w) == Poly(ex, x, y, z, t, domain='ZZ[w]') assert g.eject(t, w) == Poly(ex, x, y, z, domain='ZZ[t, w]') assert g.eject(z, t, w) == Poly(ex, x, y, domain='ZZ[z, t, w]') raises(DomainError, lambda: Poly(x*y, x, y, domain=ZZ[z]).eject(y)) raises(NotImplementedError, lambda: Poly(x*y, x, y, z).eject(y)) def test_Poly_exclude(): assert Poly(x, x, y).exclude() == Poly(x, x) assert Poly(x*y, x, y).exclude() == Poly(x*y, x, y) assert Poly(1, x, y).exclude() == Poly(1, x, y) def test_Poly__gen_to_level(): assert Poly(1, x, y)._gen_to_level(-2) == 0 assert Poly(1, x, y)._gen_to_level(-1) == 1 assert Poly(1, x, y)._gen_to_level( 0) == 0 assert Poly(1, x, y)._gen_to_level( 1) == 1 raises(PolynomialError, lambda: Poly(1, x, y)._gen_to_level(-3)) raises(PolynomialError, lambda: Poly(1, x, y)._gen_to_level( 2)) assert Poly(1, x, y)._gen_to_level(x) == 0 assert Poly(1, x, y)._gen_to_level(y) == 1 assert Poly(1, x, y)._gen_to_level('x') == 0 assert Poly(1, x, y)._gen_to_level('y') == 1 raises(PolynomialError, lambda: Poly(1, x, y)._gen_to_level(z)) raises(PolynomialError, lambda: Poly(1, x, y)._gen_to_level('z')) def test_Poly_degree(): assert Poly(0, x).degree() is -oo assert Poly(1, x).degree() == 0 assert Poly(x, x).degree() == 1 assert Poly(0, x).degree(gen=0) is -oo assert Poly(1, x).degree(gen=0) == 0 assert Poly(x, x).degree(gen=0) == 1 assert Poly(0, x).degree(gen=x) is -oo assert Poly(1, x).degree(gen=x) == 0 assert Poly(x, x).degree(gen=x) == 1 assert Poly(0, x).degree(gen='x') is -oo assert Poly(1, x).degree(gen='x') == 0 assert Poly(x, x).degree(gen='x') == 1 raises(PolynomialError, lambda: Poly(1, x).degree(gen=1)) raises(PolynomialError, lambda: Poly(1, x).degree(gen=y)) raises(PolynomialError, lambda: Poly(1, x).degree(gen='y')) assert Poly(1, x, y).degree() == 0 assert Poly(2*y, x, y).degree() == 0 assert Poly(x*y, x, y).degree() == 1 assert Poly(1, x, y).degree(gen=x) == 0 assert Poly(2*y, x, y).degree(gen=x) == 0 assert Poly(x*y, x, y).degree(gen=x) == 1 assert Poly(1, x, y).degree(gen=y) == 0 assert Poly(2*y, x, y).degree(gen=y) == 1 assert Poly(x*y, x, y).degree(gen=y) == 1 assert degree(0, x) is -oo assert degree(1, x) == 0 assert degree(x, x) == 1 assert degree(x*y**2, x) == 1 assert degree(x*y**2, y) == 2 assert degree(x*y**2, z) == 0 assert degree(pi) == 1 raises(TypeError, lambda: degree(y**2 + x**3)) raises(TypeError, lambda: degree(y**2 + x**3, 1)) raises(PolynomialError, lambda: degree(x, 1.1)) raises(PolynomialError, lambda: degree(x**2/(x**3 + 1), x)) assert degree(Poly(0,x),z) is -oo assert degree(Poly(1,x),z) == 0 assert degree(Poly(x**2+y**3,y)) == 3 assert degree(Poly(y**2 + x**3, y, x), 1) == 3 assert degree(Poly(y**2 + x**3, x), z) == 0 assert degree(Poly(y**2 + x**3 + z**4, x), z) == 4 def test_Poly_degree_list(): assert Poly(0, x).degree_list() == (-oo,) assert Poly(0, x, y).degree_list() == (-oo, -oo) assert Poly(0, x, y, z).degree_list() == (-oo, -oo, -oo) assert Poly(1, x).degree_list() == (0,) assert Poly(1, x, y).degree_list() == (0, 0) assert Poly(1, x, y, z).degree_list() == (0, 0, 0) assert Poly(x**2*y + x**3*z**2 + 1).degree_list() == (3, 1, 2) assert degree_list(1, x) == (0,) assert degree_list(x, x) == (1,) assert degree_list(x*y**2) == (1, 2) raises(ComputationFailed, lambda: degree_list(1)) def test_Poly_total_degree(): assert Poly(x**2*y + x**3*z**2 + 1).total_degree() == 5 assert Poly(x**2 + z**3).total_degree() == 3 assert Poly(x*y*z + z**4).total_degree() == 4 assert Poly(x**3 + x + 1).total_degree() == 3 assert total_degree(x*y + z**3) == 3 assert total_degree(x*y + z**3, x, y) == 2 assert total_degree(1) == 0 assert total_degree(Poly(y**2 + x**3 + z**4)) == 4 assert total_degree(Poly(y**2 + x**3 + z**4, x)) == 3 assert total_degree(Poly(y**2 + x**3 + z**4, x), z) == 4 assert total_degree(Poly(x**9 + x*z*y + x**3*z**2 + z**7,x), z) == 7 def test_Poly_homogenize(): assert Poly(x**2+y).homogenize(z) == Poly(x**2+y*z) assert Poly(x+y).homogenize(z) == Poly(x+y, x, y, z) assert Poly(x+y**2).homogenize(y) == Poly(x*y+y**2) def test_Poly_homogeneous_order(): assert Poly(0, x, y).homogeneous_order() is -oo assert Poly(1, x, y).homogeneous_order() == 0 assert Poly(x, x, y).homogeneous_order() == 1 assert Poly(x*y, x, y).homogeneous_order() == 2 assert Poly(x + 1, x, y).homogeneous_order() is None assert Poly(x*y + x, x, y).homogeneous_order() is None assert Poly(x**5 + 2*x**3*y**2 + 9*x*y**4).homogeneous_order() == 5 assert Poly(x**5 + 2*x**3*y**3 + 9*x*y**4).homogeneous_order() is None def test_Poly_LC(): assert Poly(0, x).LC() == 0 assert Poly(1, x).LC() == 1 assert Poly(2*x**2 + x, x).LC() == 2 assert Poly(x*y**7 + 2*x**2*y**3).LC('lex') == 2 assert Poly(x*y**7 + 2*x**2*y**3).LC('grlex') == 1 assert LC(x*y**7 + 2*x**2*y**3, order='lex') == 2 assert LC(x*y**7 + 2*x**2*y**3, order='grlex') == 1 def test_Poly_TC(): assert Poly(0, x).TC() == 0 assert Poly(1, x).TC() == 1 assert Poly(2*x**2 + x, x).TC() == 0 def test_Poly_EC(): assert Poly(0, x).EC() == 0 assert Poly(1, x).EC() == 1 assert Poly(2*x**2 + x, x).EC() == 1 assert Poly(x*y**7 + 2*x**2*y**3).EC('lex') == 1 assert Poly(x*y**7 + 2*x**2*y**3).EC('grlex') == 2 def test_Poly_coeff(): assert Poly(0, x).coeff_monomial(1) == 0 assert Poly(0, x).coeff_monomial(x) == 0 assert Poly(1, x).coeff_monomial(1) == 1 assert Poly(1, x).coeff_monomial(x) == 0 assert Poly(x**8, x).coeff_monomial(1) == 0 assert Poly(x**8, x).coeff_monomial(x**7) == 0 assert Poly(x**8, x).coeff_monomial(x**8) == 1 assert Poly(x**8, x).coeff_monomial(x**9) == 0 assert Poly(3*x*y**2 + 1, x, y).coeff_monomial(1) == 1 assert Poly(3*x*y**2 + 1, x, y).coeff_monomial(x*y**2) == 3 p = Poly(24*x*y*exp(8) + 23*x, x, y) assert p.coeff_monomial(x) == 23 assert p.coeff_monomial(y) == 0 assert p.coeff_monomial(x*y) == 24*exp(8) assert p.as_expr().coeff(x) == 24*y*exp(8) + 23 raises(NotImplementedError, lambda: p.coeff(x)) raises(ValueError, lambda: Poly(x + 1).coeff_monomial(0)) raises(ValueError, lambda: Poly(x + 1).coeff_monomial(3*x)) raises(ValueError, lambda: Poly(x + 1).coeff_monomial(3*x*y)) def test_Poly_nth(): assert Poly(0, x).nth(0) == 0 assert Poly(0, x).nth(1) == 0 assert Poly(1, x).nth(0) == 1 assert Poly(1, x).nth(1) == 0 assert Poly(x**8, x).nth(0) == 0 assert Poly(x**8, x).nth(7) == 0 assert Poly(x**8, x).nth(8) == 1 assert Poly(x**8, x).nth(9) == 0 assert Poly(3*x*y**2 + 1, x, y).nth(0, 0) == 1 assert Poly(3*x*y**2 + 1, x, y).nth(1, 2) == 3 raises(ValueError, lambda: Poly(x*y + 1, x, y).nth(1)) def test_Poly_LM(): assert Poly(0, x).LM() == (0,) assert Poly(1, x).LM() == (0,) assert Poly(2*x**2 + x, x).LM() == (2,) assert Poly(x*y**7 + 2*x**2*y**3).LM('lex') == (2, 3) assert Poly(x*y**7 + 2*x**2*y**3).LM('grlex') == (1, 7) assert LM(x*y**7 + 2*x**2*y**3, order='lex') == x**2*y**3 assert LM(x*y**7 + 2*x**2*y**3, order='grlex') == x*y**7 def test_Poly_LM_custom_order(): f = Poly(x**2*y**3*z + x**2*y*z**3 + x*y*z + 1) rev_lex = lambda monom: tuple(reversed(monom)) assert f.LM(order='lex') == (2, 3, 1) assert f.LM(order=rev_lex) == (2, 1, 3) def test_Poly_EM(): assert Poly(0, x).EM() == (0,) assert Poly(1, x).EM() == (0,) assert Poly(2*x**2 + x, x).EM() == (1,) assert Poly(x*y**7 + 2*x**2*y**3).EM('lex') == (1, 7) assert Poly(x*y**7 + 2*x**2*y**3).EM('grlex') == (2, 3) def test_Poly_LT(): assert Poly(0, x).LT() == ((0,), 0) assert Poly(1, x).LT() == ((0,), 1) assert Poly(2*x**2 + x, x).LT() == ((2,), 2) assert Poly(x*y**7 + 2*x**2*y**3).LT('lex') == ((2, 3), 2) assert Poly(x*y**7 + 2*x**2*y**3).LT('grlex') == ((1, 7), 1) assert LT(x*y**7 + 2*x**2*y**3, order='lex') == 2*x**2*y**3 assert LT(x*y**7 + 2*x**2*y**3, order='grlex') == x*y**7 def test_Poly_ET(): assert Poly(0, x).ET() == ((0,), 0) assert Poly(1, x).ET() == ((0,), 1) assert Poly(2*x**2 + x, x).ET() == ((1,), 1) assert Poly(x*y**7 + 2*x**2*y**3).ET('lex') == ((1, 7), 1) assert Poly(x*y**7 + 2*x**2*y**3).ET('grlex') == ((2, 3), 2) def test_Poly_max_norm(): assert Poly(-1, x).max_norm() == 1 assert Poly( 0, x).max_norm() == 0 assert Poly( 1, x).max_norm() == 1 def test_Poly_l1_norm(): assert Poly(-1, x).l1_norm() == 1 assert Poly( 0, x).l1_norm() == 0 assert Poly( 1, x).l1_norm() == 1 def test_Poly_clear_denoms(): coeff, poly = Poly(x + 2, x).clear_denoms() assert coeff == 1 and poly == Poly( x + 2, x, domain='ZZ') and poly.get_domain() == ZZ coeff, poly = Poly(x/2 + 1, x).clear_denoms() assert coeff == 2 and poly == Poly( x + 2, x, domain='QQ') and poly.get_domain() == QQ coeff, poly = Poly(x/2 + 1, x).clear_denoms(convert=True) assert coeff == 2 and poly == Poly( x + 2, x, domain='ZZ') and poly.get_domain() == ZZ coeff, poly = Poly(x/y + 1, x).clear_denoms(convert=True) assert coeff == y and poly == Poly( x + y, x, domain='ZZ[y]') and poly.get_domain() == ZZ[y] coeff, poly = Poly(x/3 + sqrt(2), x, domain='EX').clear_denoms() assert coeff == 3 and poly == Poly( x + 3*sqrt(2), x, domain='EX') and poly.get_domain() == EX coeff, poly = Poly( x/3 + sqrt(2), x, domain='EX').clear_denoms(convert=True) assert coeff == 3 and poly == Poly( x + 3*sqrt(2), x, domain='EX') and poly.get_domain() == EX def test_Poly_rat_clear_denoms(): f = Poly(x**2/y + 1, x) g = Poly(x**3 + y, x) assert f.rat_clear_denoms(g) == \ (Poly(x**2 + y, x), Poly(y*x**3 + y**2, x)) f = f.set_domain(EX) g = g.set_domain(EX) assert f.rat_clear_denoms(g) == (f, g) def test_issue_20427(): f = Poly(-117968192370600*18**(S(1)/3)/(217603955769048*(24201 + 253*sqrt(9165))**(S(1)/3) + 2273005839412*sqrt(9165)*(24201 + 253*sqrt(9165))**(S(1)/3)) - 15720318185*2**(S(2)/3)*3**(S(1)/3)*(24201 + 253*sqrt(9165))**(S(2)/3)/(217603955769048*(24201 + 253*sqrt(9165))** (S(1)/3) + 2273005839412*sqrt(9165)*(24201 + 253*sqrt(9165))**(S(1)/3)) + 15720318185*12**(S(1)/3)*(24201 + 253*sqrt(9165))**(S(2)/3)/( 217603955769048*(24201 + 253*sqrt(9165))**(S(1)/3) + 2273005839412* sqrt(9165)*(24201 + 253*sqrt(9165))**(S(1)/3)) + 117968192370600*2**( S(1)/3)*3**(S(2)/3)/(217603955769048*(24201 + 253*sqrt(9165))**(S(1)/3) + 2273005839412*sqrt(9165)*(24201 + 253*sqrt(9165))**(S(1)/3)), x) assert f == Poly(0, x, domain='EX') def test_Poly_integrate(): assert Poly(x + 1).integrate() == Poly(x**2/2 + x) assert Poly(x + 1).integrate(x) == Poly(x**2/2 + x) assert Poly(x + 1).integrate((x, 1)) == Poly(x**2/2 + x) assert Poly(x*y + 1).integrate(x) == Poly(x**2*y/2 + x) assert Poly(x*y + 1).integrate(y) == Poly(x*y**2/2 + y) assert Poly(x*y + 1).integrate(x, x) == Poly(x**3*y/6 + x**2/2) assert Poly(x*y + 1).integrate(y, y) == Poly(x*y**3/6 + y**2/2) assert Poly(x*y + 1).integrate((x, 2)) == Poly(x**3*y/6 + x**2/2) assert Poly(x*y + 1).integrate((y, 2)) == Poly(x*y**3/6 + y**2/2) assert Poly(x*y + 1).integrate(x, y) == Poly(x**2*y**2/4 + x*y) assert Poly(x*y + 1).integrate(y, x) == Poly(x**2*y**2/4 + x*y) def test_Poly_diff(): assert Poly(x**2 + x).diff() == Poly(2*x + 1) assert Poly(x**2 + x).diff(x) == Poly(2*x + 1) assert Poly(x**2 + x).diff((x, 1)) == Poly(2*x + 1) assert Poly(x**2*y**2 + x*y).diff(x) == Poly(2*x*y**2 + y) assert Poly(x**2*y**2 + x*y).diff(y) == Poly(2*x**2*y + x) assert Poly(x**2*y**2 + x*y).diff(x, x) == Poly(2*y**2, x, y) assert Poly(x**2*y**2 + x*y).diff(y, y) == Poly(2*x**2, x, y) assert Poly(x**2*y**2 + x*y).diff((x, 2)) == Poly(2*y**2, x, y) assert Poly(x**2*y**2 + x*y).diff((y, 2)) == Poly(2*x**2, x, y) assert Poly(x**2*y**2 + x*y).diff(x, y) == Poly(4*x*y + 1) assert Poly(x**2*y**2 + x*y).diff(y, x) == Poly(4*x*y + 1) def test_issue_9585(): assert diff(Poly(x**2 + x)) == Poly(2*x + 1) assert diff(Poly(x**2 + x), x, evaluate=False) == \ Derivative(Poly(x**2 + x), x) assert Derivative(Poly(x**2 + x), x).doit() == Poly(2*x + 1) def test_Poly_eval(): assert Poly(0, x).eval(7) == 0 assert Poly(1, x).eval(7) == 1 assert Poly(x, x).eval(7) == 7 assert Poly(0, x).eval(0, 7) == 0 assert Poly(1, x).eval(0, 7) == 1 assert Poly(x, x).eval(0, 7) == 7 assert Poly(0, x).eval(x, 7) == 0 assert Poly(1, x).eval(x, 7) == 1 assert Poly(x, x).eval(x, 7) == 7 assert Poly(0, x).eval('x', 7) == 0 assert Poly(1, x).eval('x', 7) == 1 assert Poly(x, x).eval('x', 7) == 7 raises(PolynomialError, lambda: Poly(1, x).eval(1, 7)) raises(PolynomialError, lambda: Poly(1, x).eval(y, 7)) raises(PolynomialError, lambda: Poly(1, x).eval('y', 7)) assert Poly(123, x, y).eval(7) == Poly(123, y) assert Poly(2*y, x, y).eval(7) == Poly(2*y, y) assert Poly(x*y, x, y).eval(7) == Poly(7*y, y) assert Poly(123, x, y).eval(x, 7) == Poly(123, y) assert Poly(2*y, x, y).eval(x, 7) == Poly(2*y, y) assert Poly(x*y, x, y).eval(x, 7) == Poly(7*y, y) assert Poly(123, x, y).eval(y, 7) == Poly(123, x) assert Poly(2*y, x, y).eval(y, 7) == Poly(14, x) assert Poly(x*y, x, y).eval(y, 7) == Poly(7*x, x) assert Poly(x*y + y, x, y).eval({x: 7}) == Poly(8*y, y) assert Poly(x*y + y, x, y).eval({y: 7}) == Poly(7*x + 7, x) assert Poly(x*y + y, x, y).eval({x: 6, y: 7}) == 49 assert Poly(x*y + y, x, y).eval({x: 7, y: 6}) == 48 assert Poly(x*y + y, x, y).eval((6, 7)) == 49 assert Poly(x*y + y, x, y).eval([6, 7]) == 49 assert Poly(x + 1, domain='ZZ').eval(S.Half) == Rational(3, 2) assert Poly(x + 1, domain='ZZ').eval(sqrt(2)) == sqrt(2) + 1 raises(ValueError, lambda: Poly(x*y + y, x, y).eval((6, 7, 8))) raises(DomainError, lambda: Poly(x + 1, domain='ZZ').eval(S.Half, auto=False)) # issue 6344 alpha = Symbol('alpha') result = (2*alpha*z - 2*alpha + z**2 + 3)/(z**2 - 2*z + 1) f = Poly(x**2 + (alpha - 1)*x - alpha + 1, x, domain='ZZ[alpha]') assert f.eval((z + 1)/(z - 1)) == result g = Poly(x**2 + (alpha - 1)*x - alpha + 1, x, y, domain='ZZ[alpha]') assert g.eval((z + 1)/(z - 1)) == Poly(result, y, domain='ZZ(alpha,z)') def test_Poly___call__(): f = Poly(2*x*y + 3*x + y + 2*z) assert f(2) == Poly(5*y + 2*z + 6) assert f(2, 5) == Poly(2*z + 31) assert f(2, 5, 7) == 45 def test_parallel_poly_from_expr(): assert parallel_poly_from_expr( [x - 1, x**2 - 1], x)[0] == [Poly(x - 1, x), Poly(x**2 - 1, x)] assert parallel_poly_from_expr( [Poly(x - 1, x), x**2 - 1], x)[0] == [Poly(x - 1, x), Poly(x**2 - 1, x)] assert parallel_poly_from_expr( [x - 1, Poly(x**2 - 1, x)], x)[0] == [Poly(x - 1, x), Poly(x**2 - 1, x)] assert parallel_poly_from_expr([Poly( x - 1, x), Poly(x**2 - 1, x)], x)[0] == [Poly(x - 1, x), Poly(x**2 - 1, x)] assert parallel_poly_from_expr( [x - 1, x**2 - 1], x, y)[0] == [Poly(x - 1, x, y), Poly(x**2 - 1, x, y)] assert parallel_poly_from_expr([Poly( x - 1, x), x**2 - 1], x, y)[0] == [Poly(x - 1, x, y), Poly(x**2 - 1, x, y)] assert parallel_poly_from_expr([x - 1, Poly( x**2 - 1, x)], x, y)[0] == [Poly(x - 1, x, y), Poly(x**2 - 1, x, y)] assert parallel_poly_from_expr([Poly(x - 1, x), Poly( x**2 - 1, x)], x, y)[0] == [Poly(x - 1, x, y), Poly(x**2 - 1, x, y)] assert parallel_poly_from_expr( [x - 1, x**2 - 1])[0] == [Poly(x - 1, x), Poly(x**2 - 1, x)] assert parallel_poly_from_expr( [Poly(x - 1, x), x**2 - 1])[0] == [Poly(x - 1, x), Poly(x**2 - 1, x)] assert parallel_poly_from_expr( [x - 1, Poly(x**2 - 1, x)])[0] == [Poly(x - 1, x), Poly(x**2 - 1, x)] assert parallel_poly_from_expr( [Poly(x - 1, x), Poly(x**2 - 1, x)])[0] == [Poly(x - 1, x), Poly(x**2 - 1, x)] assert parallel_poly_from_expr( [1, x**2 - 1])[0] == [Poly(1, x), Poly(x**2 - 1, x)] assert parallel_poly_from_expr( [1, x**2 - 1])[0] == [Poly(1, x), Poly(x**2 - 1, x)] assert parallel_poly_from_expr( [1, Poly(x**2 - 1, x)])[0] == [Poly(1, x), Poly(x**2 - 1, x)] assert parallel_poly_from_expr( [1, Poly(x**2 - 1, x)])[0] == [Poly(1, x), Poly(x**2 - 1, x)] assert parallel_poly_from_expr( [x**2 - 1, 1])[0] == [Poly(x**2 - 1, x), Poly(1, x)] assert parallel_poly_from_expr( [x**2 - 1, 1])[0] == [Poly(x**2 - 1, x), Poly(1, x)] assert parallel_poly_from_expr( [Poly(x**2 - 1, x), 1])[0] == [Poly(x**2 - 1, x), Poly(1, x)] assert parallel_poly_from_expr( [Poly(x**2 - 1, x), 1])[0] == [Poly(x**2 - 1, x), Poly(1, x)] assert parallel_poly_from_expr([Poly(x, x, y), Poly(y, x, y)], x, y, order='lex')[0] == \ [Poly(x, x, y, domain='ZZ'), Poly(y, x, y, domain='ZZ')] raises(PolificationFailed, lambda: parallel_poly_from_expr([0, 1])) def test_pdiv(): f, g = x**2 - y**2, x - y q, r = x + y, 0 F, G, Q, R = [ Poly(h, x, y) for h in (f, g, q, r) ] assert F.pdiv(G) == (Q, R) assert F.prem(G) == R assert F.pquo(G) == Q assert F.pexquo(G) == Q assert pdiv(f, g) == (q, r) assert prem(f, g) == r assert pquo(f, g) == q assert pexquo(f, g) == q assert pdiv(f, g, x, y) == (q, r) assert prem(f, g, x, y) == r assert pquo(f, g, x, y) == q assert pexquo(f, g, x, y) == q assert pdiv(f, g, (x, y)) == (q, r) assert prem(f, g, (x, y)) == r assert pquo(f, g, (x, y)) == q assert pexquo(f, g, (x, y)) == q assert pdiv(F, G) == (Q, R) assert prem(F, G) == R assert pquo(F, G) == Q assert pexquo(F, G) == Q assert pdiv(f, g, polys=True) == (Q, R) assert prem(f, g, polys=True) == R assert pquo(f, g, polys=True) == Q assert pexquo(f, g, polys=True) == Q assert pdiv(F, G, polys=False) == (q, r) assert prem(F, G, polys=False) == r assert pquo(F, G, polys=False) == q assert pexquo(F, G, polys=False) == q raises(ComputationFailed, lambda: pdiv(4, 2)) raises(ComputationFailed, lambda: prem(4, 2)) raises(ComputationFailed, lambda: pquo(4, 2)) raises(ComputationFailed, lambda: pexquo(4, 2)) def test_div(): f, g = x**2 - y**2, x - y q, r = x + y, 0 F, G, Q, R = [ Poly(h, x, y) for h in (f, g, q, r) ] assert F.div(G) == (Q, R) assert F.rem(G) == R assert F.quo(G) == Q assert F.exquo(G) == Q assert div(f, g) == (q, r) assert rem(f, g) == r assert quo(f, g) == q assert exquo(f, g) == q assert div(f, g, x, y) == (q, r) assert rem(f, g, x, y) == r assert quo(f, g, x, y) == q assert exquo(f, g, x, y) == q assert div(f, g, (x, y)) == (q, r) assert rem(f, g, (x, y)) == r assert quo(f, g, (x, y)) == q assert exquo(f, g, (x, y)) == q assert div(F, G) == (Q, R) assert rem(F, G) == R assert quo(F, G) == Q assert exquo(F, G) == Q assert div(f, g, polys=True) == (Q, R) assert rem(f, g, polys=True) == R assert quo(f, g, polys=True) == Q assert exquo(f, g, polys=True) == Q assert div(F, G, polys=False) == (q, r) assert rem(F, G, polys=False) == r assert quo(F, G, polys=False) == q assert exquo(F, G, polys=False) == q raises(ComputationFailed, lambda: div(4, 2)) raises(ComputationFailed, lambda: rem(4, 2)) raises(ComputationFailed, lambda: quo(4, 2)) raises(ComputationFailed, lambda: exquo(4, 2)) f, g = x**2 + 1, 2*x - 4 qz, rz = 0, x**2 + 1 qq, rq = x/2 + 1, 5 assert div(f, g) == (qq, rq) assert div(f, g, auto=True) == (qq, rq) assert div(f, g, auto=False) == (qz, rz) assert div(f, g, domain=ZZ) == (qz, rz) assert div(f, g, domain=QQ) == (qq, rq) assert div(f, g, domain=ZZ, auto=True) == (qq, rq) assert div(f, g, domain=ZZ, auto=False) == (qz, rz) assert div(f, g, domain=QQ, auto=True) == (qq, rq) assert div(f, g, domain=QQ, auto=False) == (qq, rq) assert rem(f, g) == rq assert rem(f, g, auto=True) == rq assert rem(f, g, auto=False) == rz assert rem(f, g, domain=ZZ) == rz assert rem(f, g, domain=QQ) == rq assert rem(f, g, domain=ZZ, auto=True) == rq assert rem(f, g, domain=ZZ, auto=False) == rz assert rem(f, g, domain=QQ, auto=True) == rq assert rem(f, g, domain=QQ, auto=False) == rq assert quo(f, g) == qq assert quo(f, g, auto=True) == qq assert quo(f, g, auto=False) == qz assert quo(f, g, domain=ZZ) == qz assert quo(f, g, domain=QQ) == qq assert quo(f, g, domain=ZZ, auto=True) == qq assert quo(f, g, domain=ZZ, auto=False) == qz assert quo(f, g, domain=QQ, auto=True) == qq assert quo(f, g, domain=QQ, auto=False) == qq f, g, q = x**2, 2*x, x/2 assert exquo(f, g) == q assert exquo(f, g, auto=True) == q raises(ExactQuotientFailed, lambda: exquo(f, g, auto=False)) raises(ExactQuotientFailed, lambda: exquo(f, g, domain=ZZ)) assert exquo(f, g, domain=QQ) == q assert exquo(f, g, domain=ZZ, auto=True) == q raises(ExactQuotientFailed, lambda: exquo(f, g, domain=ZZ, auto=False)) assert exquo(f, g, domain=QQ, auto=True) == q assert exquo(f, g, domain=QQ, auto=False) == q f, g = Poly(x**2), Poly(x) q, r = f.div(g) assert q.get_domain().is_ZZ and r.get_domain().is_ZZ r = f.rem(g) assert r.get_domain().is_ZZ q = f.quo(g) assert q.get_domain().is_ZZ q = f.exquo(g) assert q.get_domain().is_ZZ f, g = Poly(x+y, x), Poly(2*x+y, x) q, r = f.div(g) assert q.get_domain().is_Frac and r.get_domain().is_Frac # https://github.com/sympy/sympy/issues/19579 p = Poly(2+3*I, x, domain=ZZ_I) q = Poly(1-I, x, domain=ZZ_I) assert p.div(q, auto=False) == \ (Poly(0, x, domain='ZZ_I'), Poly(2 + 3*I, x, domain='ZZ_I')) assert p.div(q, auto=True) == \ (Poly(-S(1)/2 + 5*I/2, x, domain='QQ_I'), Poly(0, x, domain='QQ_I')) def test_issue_7864(): q, r = div(a, .408248290463863*a) assert abs(q - 2.44948974278318) < 1e-14 assert r == 0 def test_gcdex(): f, g = 2*x, x**2 - 16 s, t, h = x/32, Rational(-1, 16), 1 F, G, S, T, H = [ Poly(u, x, domain='QQ') for u in (f, g, s, t, h) ] assert F.half_gcdex(G) == (S, H) assert F.gcdex(G) == (S, T, H) assert F.invert(G) == S assert half_gcdex(f, g) == (s, h) assert gcdex(f, g) == (s, t, h) assert invert(f, g) == s assert half_gcdex(f, g, x) == (s, h) assert gcdex(f, g, x) == (s, t, h) assert invert(f, g, x) == s assert half_gcdex(f, g, (x,)) == (s, h) assert gcdex(f, g, (x,)) == (s, t, h) assert invert(f, g, (x,)) == s assert half_gcdex(F, G) == (S, H) assert gcdex(F, G) == (S, T, H) assert invert(F, G) == S assert half_gcdex(f, g, polys=True) == (S, H) assert gcdex(f, g, polys=True) == (S, T, H) assert invert(f, g, polys=True) == S assert half_gcdex(F, G, polys=False) == (s, h) assert gcdex(F, G, polys=False) == (s, t, h) assert invert(F, G, polys=False) == s assert half_gcdex(100, 2004) == (-20, 4) assert gcdex(100, 2004) == (-20, 1, 4) assert invert(3, 7) == 5 raises(DomainError, lambda: half_gcdex(x + 1, 2*x + 1, auto=False)) raises(DomainError, lambda: gcdex(x + 1, 2*x + 1, auto=False)) raises(DomainError, lambda: invert(x + 1, 2*x + 1, auto=False)) def test_revert(): f = Poly(1 - x**2/2 + x**4/24 - x**6/720) g = Poly(61*x**6/720 + 5*x**4/24 + x**2/2 + 1) assert f.revert(8) == g def test_subresultants(): f, g, h = x**2 - 2*x + 1, x**2 - 1, 2*x - 2 F, G, H = Poly(f), Poly(g), Poly(h) assert F.subresultants(G) == [F, G, H] assert subresultants(f, g) == [f, g, h] assert subresultants(f, g, x) == [f, g, h] assert subresultants(f, g, (x,)) == [f, g, h] assert subresultants(F, G) == [F, G, H] assert subresultants(f, g, polys=True) == [F, G, H] assert subresultants(F, G, polys=False) == [f, g, h] raises(ComputationFailed, lambda: subresultants(4, 2)) def test_resultant(): f, g, h = x**2 - 2*x + 1, x**2 - 1, 0 F, G = Poly(f), Poly(g) assert F.resultant(G) == h assert resultant(f, g) == h assert resultant(f, g, x) == h assert resultant(f, g, (x,)) == h assert resultant(F, G) == h assert resultant(f, g, polys=True) == h assert resultant(F, G, polys=False) == h assert resultant(f, g, includePRS=True) == (h, [f, g, 2*x - 2]) f, g, h = x - a, x - b, a - b F, G, H = Poly(f), Poly(g), Poly(h) assert F.resultant(G) == H assert resultant(f, g) == h assert resultant(f, g, x) == h assert resultant(f, g, (x,)) == h assert resultant(F, G) == H assert resultant(f, g, polys=True) == H assert resultant(F, G, polys=False) == h raises(ComputationFailed, lambda: resultant(4, 2)) def test_discriminant(): f, g = x**3 + 3*x**2 + 9*x - 13, -11664 F = Poly(f) assert F.discriminant() == g assert discriminant(f) == g assert discriminant(f, x) == g assert discriminant(f, (x,)) == g assert discriminant(F) == g assert discriminant(f, polys=True) == g assert discriminant(F, polys=False) == g f, g = a*x**2 + b*x + c, b**2 - 4*a*c F, G = Poly(f), Poly(g) assert F.discriminant() == G assert discriminant(f) == g assert discriminant(f, x, a, b, c) == g assert discriminant(f, (x, a, b, c)) == g assert discriminant(F) == G assert discriminant(f, polys=True) == G assert discriminant(F, polys=False) == g raises(ComputationFailed, lambda: discriminant(4)) def test_dispersion(): # We test only the API here. For more mathematical # tests see the dedicated test file. fp = poly((x + 1)*(x + 2), x) assert sorted(fp.dispersionset()) == [0, 1] assert fp.dispersion() == 1 fp = poly(x**4 - 3*x**2 + 1, x) gp = fp.shift(-3) assert sorted(fp.dispersionset(gp)) == [2, 3, 4] assert fp.dispersion(gp) == 4 def test_gcd_list(): F = [x**3 - 1, x**2 - 1, x**2 - 3*x + 2] assert gcd_list(F) == x - 1 assert gcd_list(F, polys=True) == Poly(x - 1) assert gcd_list([]) == 0 assert gcd_list([1, 2]) == 1 assert gcd_list([4, 6, 8]) == 2 assert gcd_list([x*(y + 42) - x*y - x*42]) == 0 gcd = gcd_list([], x) assert gcd.is_Number and gcd is S.Zero gcd = gcd_list([], x, polys=True) assert gcd.is_Poly and gcd.is_zero a = sqrt(2) assert gcd_list([a, -a]) == gcd_list([-a, a]) == a raises(ComputationFailed, lambda: gcd_list([], polys=True)) def test_lcm_list(): F = [x**3 - 1, x**2 - 1, x**2 - 3*x + 2] assert lcm_list(F) == x**5 - x**4 - 2*x**3 - x**2 + x + 2 assert lcm_list(F, polys=True) == Poly(x**5 - x**4 - 2*x**3 - x**2 + x + 2) assert lcm_list([]) == 1 assert lcm_list([1, 2]) == 2 assert lcm_list([4, 6, 8]) == 24 assert lcm_list([x*(y + 42) - x*y - x*42]) == 0 lcm = lcm_list([], x) assert lcm.is_Number and lcm is S.One lcm = lcm_list([], x, polys=True) assert lcm.is_Poly and lcm.is_one raises(ComputationFailed, lambda: lcm_list([], polys=True)) def test_gcd(): f, g = x**3 - 1, x**2 - 1 s, t = x**2 + x + 1, x + 1 h, r = x - 1, x**4 + x**3 - x - 1 F, G, S, T, H, R = [ Poly(u) for u in (f, g, s, t, h, r) ] assert F.cofactors(G) == (H, S, T) assert F.gcd(G) == H assert F.lcm(G) == R assert cofactors(f, g) == (h, s, t) assert gcd(f, g) == h assert lcm(f, g) == r assert cofactors(f, g, x) == (h, s, t) assert gcd(f, g, x) == h assert lcm(f, g, x) == r assert cofactors(f, g, (x,)) == (h, s, t) assert gcd(f, g, (x,)) == h assert lcm(f, g, (x,)) == r assert cofactors(F, G) == (H, S, T) assert gcd(F, G) == H assert lcm(F, G) == R assert cofactors(f, g, polys=True) == (H, S, T) assert gcd(f, g, polys=True) == H assert lcm(f, g, polys=True) == R assert cofactors(F, G, polys=False) == (h, s, t) assert gcd(F, G, polys=False) == h assert lcm(F, G, polys=False) == r f, g = 1.0*x**2 - 1.0, 1.0*x - 1.0 h, s, t = g, 1.0*x + 1.0, 1.0 assert cofactors(f, g) == (h, s, t) assert gcd(f, g) == h assert lcm(f, g) == f f, g = 1.0*x**2 - 1.0, 1.0*x - 1.0 h, s, t = g, 1.0*x + 1.0, 1.0 assert cofactors(f, g) == (h, s, t) assert gcd(f, g) == h assert lcm(f, g) == f assert cofactors(8, 6) == (2, 4, 3) assert gcd(8, 6) == 2 assert lcm(8, 6) == 24 f, g = x**2 - 3*x - 4, x**3 - 4*x**2 + x - 4 l = x**4 - 3*x**3 - 3*x**2 - 3*x - 4 h, s, t = x - 4, x + 1, x**2 + 1 assert cofactors(f, g, modulus=11) == (h, s, t) assert gcd(f, g, modulus=11) == h assert lcm(f, g, modulus=11) == l f, g = x**2 + 8*x + 7, x**3 + 7*x**2 + x + 7 l = x**4 + 8*x**3 + 8*x**2 + 8*x + 7 h, s, t = x + 7, x + 1, x**2 + 1 assert cofactors(f, g, modulus=11, symmetric=False) == (h, s, t) assert gcd(f, g, modulus=11, symmetric=False) == h assert lcm(f, g, modulus=11, symmetric=False) == l a, b = sqrt(2), -sqrt(2) assert gcd(a, b) == gcd(b, a) == sqrt(2) a, b = sqrt(-2), -sqrt(-2) assert gcd(a, b) == gcd(b, a) == sqrt(2) assert gcd(Poly(x - 2, x), Poly(I*x, x)) == Poly(1, x, domain=ZZ_I) raises(TypeError, lambda: gcd(x)) raises(TypeError, lambda: lcm(x)) def test_gcd_numbers_vs_polys(): assert isinstance(gcd(3, 9), Integer) assert isinstance(gcd(3*x, 9), Integer) assert gcd(3, 9) == 3 assert gcd(3*x, 9) == 3 assert isinstance(gcd(Rational(3, 2), Rational(9, 4)), Rational) assert isinstance(gcd(Rational(3, 2)*x, Rational(9, 4)), Rational) assert gcd(Rational(3, 2), Rational(9, 4)) == Rational(3, 4) assert gcd(Rational(3, 2)*x, Rational(9, 4)) == 1 assert isinstance(gcd(3.0, 9.0), Float) assert isinstance(gcd(3.0*x, 9.0), Float) assert gcd(3.0, 9.0) == 1.0 assert gcd(3.0*x, 9.0) == 1.0 # partial fix of 20597 assert gcd(Mul(2, 3, evaluate=False), 2) == 2 def test_terms_gcd(): assert terms_gcd(1) == 1 assert terms_gcd(1, x) == 1 assert terms_gcd(x - 1) == x - 1 assert terms_gcd(-x - 1) == -x - 1 assert terms_gcd(2*x + 3) == 2*x + 3 assert terms_gcd(6*x + 4) == Mul(2, 3*x + 2, evaluate=False) assert terms_gcd(x**3*y + x*y**3) == x*y*(x**2 + y**2) assert terms_gcd(2*x**3*y + 2*x*y**3) == 2*x*y*(x**2 + y**2) assert terms_gcd(x**3*y/2 + x*y**3/2) == x*y/2*(x**2 + y**2) assert terms_gcd(x**3*y + 2*x*y**3) == x*y*(x**2 + 2*y**2) assert terms_gcd(2*x**3*y + 4*x*y**3) == 2*x*y*(x**2 + 2*y**2) assert terms_gcd(2*x**3*y/3 + 4*x*y**3/5) == x*y*Rational(2, 15)*(5*x**2 + 6*y**2) assert terms_gcd(2.0*x**3*y + 4.1*x*y**3) == x*y*(2.0*x**2 + 4.1*y**2) assert _aresame(terms_gcd(2.0*x + 3), 2.0*x + 3) assert terms_gcd((3 + 3*x)*(x + x*y), expand=False) == \ (3*x + 3)*(x*y + x) assert terms_gcd((3 + 3*x)*(x + x*sin(3 + 3*y)), expand=False, deep=True) == \ 3*x*(x + 1)*(sin(Mul(3, y + 1, evaluate=False)) + 1) assert terms_gcd(sin(x + x*y), deep=True) == \ sin(x*(y + 1)) eq = Eq(2*x, 2*y + 2*z*y) assert terms_gcd(eq) == Eq(2*x, 2*y*(z + 1)) assert terms_gcd(eq, deep=True) == Eq(2*x, 2*y*(z + 1)) raises(TypeError, lambda: terms_gcd(x < 2)) def test_trunc(): f, g = x**5 + 2*x**4 + 3*x**3 + 4*x**2 + 5*x + 6, x**5 - x**4 + x**2 - x F, G = Poly(f), Poly(g) assert F.trunc(3) == G assert trunc(f, 3) == g assert trunc(f, 3, x) == g assert trunc(f, 3, (x,)) == g assert trunc(F, 3) == G assert trunc(f, 3, polys=True) == G assert trunc(F, 3, polys=False) == g f, g = 6*x**5 + 5*x**4 + 4*x**3 + 3*x**2 + 2*x + 1, -x**4 + x**3 - x + 1 F, G = Poly(f), Poly(g) assert F.trunc(3) == G assert trunc(f, 3) == g assert trunc(f, 3, x) == g assert trunc(f, 3, (x,)) == g assert trunc(F, 3) == G assert trunc(f, 3, polys=True) == G assert trunc(F, 3, polys=False) == g f = Poly(x**2 + 2*x + 3, modulus=5) assert f.trunc(2) == Poly(x**2 + 1, modulus=5) def test_monic(): f, g = 2*x - 1, x - S.Half F, G = Poly(f, domain='QQ'), Poly(g) assert F.monic() == G assert monic(f) == g assert monic(f, x) == g assert monic(f, (x,)) == g assert monic(F) == G assert monic(f, polys=True) == G assert monic(F, polys=False) == g raises(ComputationFailed, lambda: monic(4)) assert monic(2*x**2 + 6*x + 4, auto=False) == x**2 + 3*x + 2 raises(ExactQuotientFailed, lambda: monic(2*x + 6*x + 1, auto=False)) assert monic(2.0*x**2 + 6.0*x + 4.0) == 1.0*x**2 + 3.0*x + 2.0 assert monic(2*x**2 + 3*x + 4, modulus=5) == x**2 - x + 2 def test_content(): f, F = 4*x + 2, Poly(4*x + 2) assert F.content() == 2 assert content(f) == 2 raises(ComputationFailed, lambda: content(4)) f = Poly(2*x, modulus=3) assert f.content() == 1 def test_primitive(): f, g = 4*x + 2, 2*x + 1 F, G = Poly(f), Poly(g) assert F.primitive() == (2, G) assert primitive(f) == (2, g) assert primitive(f, x) == (2, g) assert primitive(f, (x,)) == (2, g) assert primitive(F) == (2, G) assert primitive(f, polys=True) == (2, G) assert primitive(F, polys=False) == (2, g) raises(ComputationFailed, lambda: primitive(4)) f = Poly(2*x, modulus=3) g = Poly(2.0*x, domain=RR) assert f.primitive() == (1, f) assert g.primitive() == (1.0, g) assert primitive(S('-3*x/4 + y + 11/8')) == \ S('(1/8, -6*x + 8*y + 11)') def test_compose(): f = x**12 + 20*x**10 + 150*x**8 + 500*x**6 + 625*x**4 - 2*x**3 - 10*x + 9 g = x**4 - 2*x + 9 h = x**3 + 5*x F, G, H = map(Poly, (f, g, h)) assert G.compose(H) == F assert compose(g, h) == f assert compose(g, h, x) == f assert compose(g, h, (x,)) == f assert compose(G, H) == F assert compose(g, h, polys=True) == F assert compose(G, H, polys=False) == f assert F.decompose() == [G, H] assert decompose(f) == [g, h] assert decompose(f, x) == [g, h] assert decompose(f, (x,)) == [g, h] assert decompose(F) == [G, H] assert decompose(f, polys=True) == [G, H] assert decompose(F, polys=False) == [g, h] raises(ComputationFailed, lambda: compose(4, 2)) raises(ComputationFailed, lambda: decompose(4)) assert compose(x**2 - y**2, x - y, x, y) == x**2 - 2*x*y assert compose(x**2 - y**2, x - y, y, x) == -y**2 + 2*x*y def test_shift(): assert Poly(x**2 - 2*x + 1, x).shift(2) == Poly(x**2 + 2*x + 1, x) def test_transform(): # Also test that 3-way unification is done correctly assert Poly(x**2 - 2*x + 1, x).transform(Poly(x + 1), Poly(x - 1)) == \ Poly(4, x) == \ cancel((x - 1)**2*(x**2 - 2*x + 1).subs(x, (x + 1)/(x - 1))) assert Poly(x**2 - x/2 + 1, x).transform(Poly(x + 1), Poly(x - 1)) == \ Poly(3*x**2/2 + Rational(5, 2), x) == \ cancel((x - 1)**2*(x**2 - x/2 + 1).subs(x, (x + 1)/(x - 1))) assert Poly(x**2 - 2*x + 1, x).transform(Poly(x + S.Half), Poly(x - 1)) == \ Poly(Rational(9, 4), x) == \ cancel((x - 1)**2*(x**2 - 2*x + 1).subs(x, (x + S.Half)/(x - 1))) assert Poly(x**2 - 2*x + 1, x).transform(Poly(x + 1), Poly(x - S.Half)) == \ Poly(Rational(9, 4), x) == \ cancel((x - S.Half)**2*(x**2 - 2*x + 1).subs(x, (x + 1)/(x - S.Half))) # Unify ZZ, QQ, and RR assert Poly(x**2 - 2*x + 1, x).transform(Poly(x + 1.0), Poly(x - S.Half)) == \ Poly(Rational(9, 4), x, domain='RR') == \ cancel((x - S.Half)**2*(x**2 - 2*x + 1).subs(x, (x + 1.0)/(x - S.Half))) raises(ValueError, lambda: Poly(x*y).transform(Poly(x + 1), Poly(x - 1))) raises(ValueError, lambda: Poly(x).transform(Poly(y + 1), Poly(x - 1))) raises(ValueError, lambda: Poly(x).transform(Poly(x + 1), Poly(y - 1))) raises(ValueError, lambda: Poly(x).transform(Poly(x*y + 1), Poly(x - 1))) raises(ValueError, lambda: Poly(x).transform(Poly(x + 1), Poly(x*y - 1))) def test_sturm(): f, F = x, Poly(x, domain='QQ') g, G = 1, Poly(1, x, domain='QQ') assert F.sturm() == [F, G] assert sturm(f) == [f, g] assert sturm(f, x) == [f, g] assert sturm(f, (x,)) == [f, g] assert sturm(F) == [F, G] assert sturm(f, polys=True) == [F, G] assert sturm(F, polys=False) == [f, g] raises(ComputationFailed, lambda: sturm(4)) raises(DomainError, lambda: sturm(f, auto=False)) f = Poly(S(1024)/(15625*pi**8)*x**5 - S(4096)/(625*pi**8)*x**4 + S(32)/(15625*pi**4)*x**3 - S(128)/(625*pi**4)*x**2 + Rational(1, 62500)*x - Rational(1, 625), x, domain='ZZ(pi)') assert sturm(f) == \ [Poly(x**3 - 100*x**2 + pi**4/64*x - 25*pi**4/16, x, domain='ZZ(pi)'), Poly(3*x**2 - 200*x + pi**4/64, x, domain='ZZ(pi)'), Poly((Rational(20000, 9) - pi**4/96)*x + 25*pi**4/18, x, domain='ZZ(pi)'), Poly((-3686400000000*pi**4 - 11520000*pi**8 - 9*pi**12)/(26214400000000 - 245760000*pi**4 + 576*pi**8), x, domain='ZZ(pi)')] def test_gff(): f = x**5 + 2*x**4 - x**3 - 2*x**2 assert Poly(f).gff_list() == [(Poly(x), 1), (Poly(x + 2), 4)] assert gff_list(f) == [(x, 1), (x + 2, 4)] raises(NotImplementedError, lambda: gff(f)) f = x*(x - 1)**3*(x - 2)**2*(x - 4)**2*(x - 5) assert Poly(f).gff_list() == [( Poly(x**2 - 5*x + 4), 1), (Poly(x**2 - 5*x + 4), 2), (Poly(x), 3)] assert gff_list(f) == [(x**2 - 5*x + 4, 1), (x**2 - 5*x + 4, 2), (x, 3)] raises(NotImplementedError, lambda: gff(f)) def test_norm(): a, b = sqrt(2), sqrt(3) f = Poly(a*x + b*y, x, y, extension=(a, b)) assert f.norm() == Poly(4*x**4 - 12*x**2*y**2 + 9*y**4, x, y, domain='QQ') def test_sqf_norm(): assert sqf_norm(x**2 - 2, extension=sqrt(3)) == \ (1, x**2 - 2*sqrt(3)*x + 1, x**4 - 10*x**2 + 1) assert sqf_norm(x**2 - 3, extension=sqrt(2)) == \ (1, x**2 - 2*sqrt(2)*x - 1, x**4 - 10*x**2 + 1) assert Poly(x**2 - 2, extension=sqrt(3)).sqf_norm() == \ (1, Poly(x**2 - 2*sqrt(3)*x + 1, x, extension=sqrt(3)), Poly(x**4 - 10*x**2 + 1, x, domain='QQ')) assert Poly(x**2 - 3, extension=sqrt(2)).sqf_norm() == \ (1, Poly(x**2 - 2*sqrt(2)*x - 1, x, extension=sqrt(2)), Poly(x**4 - 10*x**2 + 1, x, domain='QQ')) def test_sqf(): f = x**5 - x**3 - x**2 + 1 g = x**3 + 2*x**2 + 2*x + 1 h = x - 1 p = x**4 + x**3 - x - 1 F, G, H, P = map(Poly, (f, g, h, p)) assert F.sqf_part() == P assert sqf_part(f) == p assert sqf_part(f, x) == p assert sqf_part(f, (x,)) == p assert sqf_part(F) == P assert sqf_part(f, polys=True) == P assert sqf_part(F, polys=False) == p assert F.sqf_list() == (1, [(G, 1), (H, 2)]) assert sqf_list(f) == (1, [(g, 1), (h, 2)]) assert sqf_list(f, x) == (1, [(g, 1), (h, 2)]) assert sqf_list(f, (x,)) == (1, [(g, 1), (h, 2)]) assert sqf_list(F) == (1, [(G, 1), (H, 2)]) assert sqf_list(f, polys=True) == (1, [(G, 1), (H, 2)]) assert sqf_list(F, polys=False) == (1, [(g, 1), (h, 2)]) assert F.sqf_list_include() == [(G, 1), (H, 2)] raises(ComputationFailed, lambda: sqf_part(4)) assert sqf(1) == 1 assert sqf_list(1) == (1, []) assert sqf((2*x**2 + 2)**7) == 128*(x**2 + 1)**7 assert sqf(f) == g*h**2 assert sqf(f, x) == g*h**2 assert sqf(f, (x,)) == g*h**2 d = x**2 + y**2 assert sqf(f/d) == (g*h**2)/d assert sqf(f/d, x) == (g*h**2)/d assert sqf(f/d, (x,)) == (g*h**2)/d assert sqf(x - 1) == x - 1 assert sqf(-x - 1) == -x - 1 assert sqf(x - 1) == x - 1 assert sqf(6*x - 10) == Mul(2, 3*x - 5, evaluate=False) assert sqf((6*x - 10)/(3*x - 6)) == Rational(2, 3)*((3*x - 5)/(x - 2)) assert sqf(Poly(x**2 - 2*x + 1)) == (x - 1)**2 f = 3 + x - x*(1 + x) + x**2 assert sqf(f) == 3 f = (x**2 + 2*x + 1)**20000000000 assert sqf(f) == (x + 1)**40000000000 assert sqf_list(f) == (1, [(x + 1, 40000000000)]) def test_factor(): f = x**5 - x**3 - x**2 + 1 u = x + 1 v = x - 1 w = x**2 + x + 1 F, U, V, W = map(Poly, (f, u, v, w)) assert F.factor_list() == (1, [(U, 1), (V, 2), (W, 1)]) assert factor_list(f) == (1, [(u, 1), (v, 2), (w, 1)]) assert factor_list(f, x) == (1, [(u, 1), (v, 2), (w, 1)]) assert factor_list(f, (x,)) == (1, [(u, 1), (v, 2), (w, 1)]) assert factor_list(F) == (1, [(U, 1), (V, 2), (W, 1)]) assert factor_list(f, polys=True) == (1, [(U, 1), (V, 2), (W, 1)]) assert factor_list(F, polys=False) == (1, [(u, 1), (v, 2), (w, 1)]) assert F.factor_list_include() == [(U, 1), (V, 2), (W, 1)] assert factor_list(1) == (1, []) assert factor_list(6) == (6, []) assert factor_list(sqrt(3), x) == (sqrt(3), []) assert factor_list((-1)**x, x) == (1, [(-1, x)]) assert factor_list((2*x)**y, x) == (1, [(2, y), (x, y)]) assert factor_list(sqrt(x*y), x) == (1, [(x*y, S.Half)]) assert factor(6) == 6 and factor(6).is_Integer assert factor_list(3*x) == (3, [(x, 1)]) assert factor_list(3*x**2) == (3, [(x, 2)]) assert factor(3*x) == 3*x assert factor(3*x**2) == 3*x**2 assert factor((2*x**2 + 2)**7) == 128*(x**2 + 1)**7 assert factor(f) == u*v**2*w assert factor(f, x) == u*v**2*w assert factor(f, (x,)) == u*v**2*w g, p, q, r = x**2 - y**2, x - y, x + y, x**2 + 1 assert factor(f/g) == (u*v**2*w)/(p*q) assert factor(f/g, x) == (u*v**2*w)/(p*q) assert factor(f/g, (x,)) == (u*v**2*w)/(p*q) p = Symbol('p', positive=True) i = Symbol('i', integer=True) r = Symbol('r', real=True) assert factor(sqrt(x*y)).is_Pow is True assert factor(sqrt(3*x**2 - 3)) == sqrt(3)*sqrt((x - 1)*(x + 1)) assert factor(sqrt(3*x**2 + 3)) == sqrt(3)*sqrt(x**2 + 1) assert factor((y*x**2 - y)**i) == y**i*(x - 1)**i*(x + 1)**i assert factor((y*x**2 + y)**i) == y**i*(x**2 + 1)**i assert factor((y*x**2 - y)**t) == (y*(x - 1)*(x + 1))**t assert factor((y*x**2 + y)**t) == (y*(x**2 + 1))**t f = sqrt(expand((r**2 + 1)*(p + 1)*(p - 1)*(p - 2)**3)) g = sqrt((p - 2)**3*(p - 1))*sqrt(p + 1)*sqrt(r**2 + 1) assert factor(f) == g assert factor(g) == g g = (x - 1)**5*(r**2 + 1) f = sqrt(expand(g)) assert factor(f) == sqrt(g) f = Poly(sin(1)*x + 1, x, domain=EX) assert f.factor_list() == (1, [(f, 1)]) f = x**4 + 1 assert factor(f) == f assert factor(f, extension=I) == (x**2 - I)*(x**2 + I) assert factor(f, gaussian=True) == (x**2 - I)*(x**2 + I) assert factor( f, extension=sqrt(2)) == (x**2 + sqrt(2)*x + 1)*(x**2 - sqrt(2)*x + 1) assert factor(x**2 + 4*I*x - 4) == (x + 2*I)**2 f = x**2 + 2*I*x - 4 assert factor(f) == f f = 8192*x**2 + x*(22656 + 175232*I) - 921416 + 242313*I f_zzi = I*(x*(64 - 64*I) + 773 + 596*I)**2 f_qqi = 8192*(x + S(177)/128 + 1369*I/128)**2 assert factor(f) == f_zzi assert factor(f, domain=ZZ_I) == f_zzi assert factor(f, domain=QQ_I) == f_qqi f = x**2 + 2*sqrt(2)*x + 2 assert factor(f, extension=sqrt(2)) == (x + sqrt(2))**2 assert factor(f**3, extension=sqrt(2)) == (x + sqrt(2))**6 assert factor(x**2 - 2*y**2, extension=sqrt(2)) == \ (x + sqrt(2)*y)*(x - sqrt(2)*y) assert factor(2*x**2 - 4*y**2, extension=sqrt(2)) == \ 2*((x + sqrt(2)*y)*(x - sqrt(2)*y)) assert factor(x - 1) == x - 1 assert factor(-x - 1) == -x - 1 assert factor(x - 1) == x - 1 assert factor(6*x - 10) == Mul(2, 3*x - 5, evaluate=False) assert factor(x**11 + x + 1, modulus=65537, symmetric=True) == \ (x**2 + x + 1)*(x**9 - x**8 + x**6 - x**5 + x**3 - x** 2 + 1) assert factor(x**11 + x + 1, modulus=65537, symmetric=False) == \ (x**2 + x + 1)*(x**9 + 65536*x**8 + x**6 + 65536*x**5 + x**3 + 65536*x** 2 + 1) f = x/pi + x*sin(x)/pi g = y/(pi**2 + 2*pi + 1) + y*sin(x)/(pi**2 + 2*pi + 1) assert factor(f) == x*(sin(x) + 1)/pi assert factor(g) == y*(sin(x) + 1)/(pi + 1)**2 assert factor(Eq( x**2 + 2*x + 1, x**3 + 1)) == Eq((x + 1)**2, (x + 1)*(x**2 - x + 1)) f = (x**2 - 1)/(x**2 + 4*x + 4) assert factor(f) == (x + 1)*(x - 1)/(x + 2)**2 assert factor(f, x) == (x + 1)*(x - 1)/(x + 2)**2 f = 3 + x - x*(1 + x) + x**2 assert factor(f) == 3 assert factor(f, x) == 3 assert factor(1/(x**2 + 2*x + 1/x) - 1) == -((1 - x + 2*x**2 + x**3)/(1 + 2*x**2 + x**3)) assert factor(f, expand=False) == f raises(PolynomialError, lambda: factor(f, x, expand=False)) raises(FlagError, lambda: factor(x**2 - 1, polys=True)) assert factor([x, Eq(x**2 - y**2, Tuple(x**2 - z**2, 1/x + 1/y))]) == \ [x, Eq((x - y)*(x + y), Tuple((x - z)*(x + z), (x + y)/x/y))] assert not isinstance( Poly(x**3 + x + 1).factor_list()[1][0][0], PurePoly) is True assert isinstance( PurePoly(x**3 + x + 1).factor_list()[1][0][0], PurePoly) is True assert factor(sqrt(-x)) == sqrt(-x) # issue 5917 e = (-2*x*(-x + 1)*(x - 1)*(-x*(-x + 1)*(x - 1) - x*(x - 1)**2)*(x**2*(x - 1) - x*(x - 1) - x) - (-2*x**2*(x - 1)**2 - x*(-x + 1)*(-x*(-x + 1) + x*(x - 1)))*(x**2*(x - 1)**4 - x*(-x*(-x + 1)*(x - 1) - x*(x - 1)**2))) assert factor(e) == 0 # deep option assert factor(sin(x**2 + x) + x, deep=True) == sin(x*(x + 1)) + x assert factor(sin(x**2 + x)*x, deep=True) == sin(x*(x + 1))*x assert factor(sqrt(x**2)) == sqrt(x**2) # issue 13149 assert factor(expand((0.5*x+1)*(0.5*y+1))) == Mul(1.0, 0.5*x + 1.0, 0.5*y + 1.0, evaluate = False) assert factor(expand((0.5*x+0.5)**2)) == 0.25*(1.0*x + 1.0)**2 eq = x**2*y**2 + 11*x**2*y + 30*x**2 + 7*x*y**2 + 77*x*y + 210*x + 12*y**2 + 132*y + 360 assert factor(eq, x) == (x + 3)*(x + 4)*(y**2 + 11*y + 30) assert factor(eq, x, deep=True) == (x + 3)*(x + 4)*(y**2 + 11*y + 30) assert factor(eq, y, deep=True) == (y + 5)*(y + 6)*(x**2 + 7*x + 12) # fraction option f = 5*x + 3*exp(2 - 7*x) assert factor(f, deep=True) == factor(f, deep=True, fraction=True) assert factor(f, deep=True, fraction=False) == 5*x + 3*exp(2)*exp(-7*x) def test_factor_large(): f = (x**2 + 4*x + 4)**10000000*(x**2 + 1)*(x**2 + 2*x + 1)**1234567 g = ((x**2 + 2*x + 1)**3000*y**2 + (x**2 + 2*x + 1)**3000*2*y + ( x**2 + 2*x + 1)**3000) assert factor(f) == (x + 2)**20000000*(x**2 + 1)*(x + 1)**2469134 assert factor(g) == (x + 1)**6000*(y + 1)**2 assert factor_list( f) == (1, [(x + 1, 2469134), (x + 2, 20000000), (x**2 + 1, 1)]) assert factor_list(g) == (1, [(y + 1, 2), (x + 1, 6000)]) f = (x**2 - y**2)**200000*(x**7 + 1) g = (x**2 + y**2)**200000*(x**7 + 1) assert factor(f) == \ (x + 1)*(x - y)**200000*(x + y)**200000*(x**6 - x**5 + x**4 - x**3 + x**2 - x + 1) assert factor(g, gaussian=True) == \ (x + 1)*(x - I*y)**200000*(x + I*y)**200000*(x**6 - x**5 + x**4 - x**3 + x**2 - x + 1) assert factor_list(f) == \ (1, [(x + 1, 1), (x - y, 200000), (x + y, 200000), (x**6 - x**5 + x**4 - x**3 + x**2 - x + 1, 1)]) assert factor_list(g, gaussian=True) == \ (1, [(x + 1, 1), (x - I*y, 200000), (x + I*y, 200000), ( x**6 - x**5 + x**4 - x**3 + x**2 - x + 1, 1)]) def test_factor_noeval(): assert factor(6*x - 10) == Mul(2, 3*x - 5, evaluate=False) assert factor((6*x - 10)/(3*x - 6)) == Mul(Rational(2, 3), 3*x - 5, 1/(x - 2)) def test_intervals(): assert intervals(0) == [] assert intervals(1) == [] assert intervals(x, sqf=True) == [(0, 0)] assert intervals(x) == [((0, 0), 1)] assert intervals(x**128) == [((0, 0), 128)] assert intervals([x**2, x**4]) == [((0, 0), {0: 2, 1: 4})] f = Poly((x*Rational(2, 5) - Rational(17, 3))*(4*x + Rational(1, 257))) assert f.intervals(sqf=True) == [(-1, 0), (14, 15)] assert f.intervals() == [((-1, 0), 1), ((14, 15), 1)] assert f.intervals(fast=True, sqf=True) == [(-1, 0), (14, 15)] assert f.intervals(fast=True) == [((-1, 0), 1), ((14, 15), 1)] assert f.intervals(eps=Rational(1, 10)) == f.intervals(eps=0.1) == \ [((Rational(-1, 258), 0), 1), ((Rational(85, 6), Rational(85, 6)), 1)] assert f.intervals(eps=Rational(1, 100)) == f.intervals(eps=0.01) == \ [((Rational(-1, 258), 0), 1), ((Rational(85, 6), Rational(85, 6)), 1)] assert f.intervals(eps=Rational(1, 1000)) == f.intervals(eps=0.001) == \ [((Rational(-1, 1002), 0), 1), ((Rational(85, 6), Rational(85, 6)), 1)] assert f.intervals(eps=Rational(1, 10000)) == f.intervals(eps=0.0001) == \ [((Rational(-1, 1028), Rational(-1, 1028)), 1), ((Rational(85, 6), Rational(85, 6)), 1)] f = (x*Rational(2, 5) - Rational(17, 3))*(4*x + Rational(1, 257)) assert intervals(f, sqf=True) == [(-1, 0), (14, 15)] assert intervals(f) == [((-1, 0), 1), ((14, 15), 1)] assert intervals(f, eps=Rational(1, 10)) == intervals(f, eps=0.1) == \ [((Rational(-1, 258), 0), 1), ((Rational(85, 6), Rational(85, 6)), 1)] assert intervals(f, eps=Rational(1, 100)) == intervals(f, eps=0.01) == \ [((Rational(-1, 258), 0), 1), ((Rational(85, 6), Rational(85, 6)), 1)] assert intervals(f, eps=Rational(1, 1000)) == intervals(f, eps=0.001) == \ [((Rational(-1, 1002), 0), 1), ((Rational(85, 6), Rational(85, 6)), 1)] assert intervals(f, eps=Rational(1, 10000)) == intervals(f, eps=0.0001) == \ [((Rational(-1, 1028), Rational(-1, 1028)), 1), ((Rational(85, 6), Rational(85, 6)), 1)] f = Poly((x**2 - 2)*(x**2 - 3)**7*(x + 1)*(7*x + 3)**3) assert f.intervals() == \ [((-2, Rational(-3, 2)), 7), ((Rational(-3, 2), -1), 1), ((-1, -1), 1), ((-1, 0), 3), ((1, Rational(3, 2)), 1), ((Rational(3, 2), 2), 7)] assert intervals([x**5 - 200, x**5 - 201]) == \ [((Rational(75, 26), Rational(101, 35)), {0: 1}), ((Rational(309, 107), Rational(26, 9)), {1: 1})] assert intervals([x**5 - 200, x**5 - 201], fast=True) == \ [((Rational(75, 26), Rational(101, 35)), {0: 1}), ((Rational(309, 107), Rational(26, 9)), {1: 1})] assert intervals([x**2 - 200, x**2 - 201]) == \ [((Rational(-71, 5), Rational(-85, 6)), {1: 1}), ((Rational(-85, 6), -14), {0: 1}), ((14, Rational(85, 6)), {0: 1}), ((Rational(85, 6), Rational(71, 5)), {1: 1})] assert intervals([x + 1, x + 2, x - 1, x + 1, 1, x - 1, x - 1, (x - 2)**2]) == \ [((-2, -2), {1: 1}), ((-1, -1), {0: 1, 3: 1}), ((1, 1), {2: 1, 5: 1, 6: 1}), ((2, 2), {7: 2})] f, g, h = x**2 - 2, x**4 - 4*x**2 + 4, x - 1 assert intervals(f, inf=Rational(7, 4), sqf=True) == [] assert intervals(f, inf=Rational(7, 5), sqf=True) == [(Rational(7, 5), Rational(3, 2))] assert intervals(f, sup=Rational(7, 4), sqf=True) == [(-2, -1), (1, Rational(3, 2))] assert intervals(f, sup=Rational(7, 5), sqf=True) == [(-2, -1)] assert intervals(g, inf=Rational(7, 4)) == [] assert intervals(g, inf=Rational(7, 5)) == [((Rational(7, 5), Rational(3, 2)), 2)] assert intervals(g, sup=Rational(7, 4)) == [((-2, -1), 2), ((1, Rational(3, 2)), 2)] assert intervals(g, sup=Rational(7, 5)) == [((-2, -1), 2)] assert intervals([g, h], inf=Rational(7, 4)) == [] assert intervals([g, h], inf=Rational(7, 5)) == [((Rational(7, 5), Rational(3, 2)), {0: 2})] assert intervals([g, h], sup=S( 7)/4) == [((-2, -1), {0: 2}), ((1, 1), {1: 1}), ((1, Rational(3, 2)), {0: 2})] assert intervals( [g, h], sup=Rational(7, 5)) == [((-2, -1), {0: 2}), ((1, 1), {1: 1})] assert intervals([x + 2, x**2 - 2]) == \ [((-2, -2), {0: 1}), ((-2, -1), {1: 1}), ((1, 2), {1: 1})] assert intervals([x + 2, x**2 - 2], strict=True) == \ [((-2, -2), {0: 1}), ((Rational(-3, 2), -1), {1: 1}), ((1, 2), {1: 1})] f = 7*z**4 - 19*z**3 + 20*z**2 + 17*z + 20 assert intervals(f) == [] real_part, complex_part = intervals(f, all=True, sqf=True) assert real_part == [] assert all(re(a) < re(r) < re(b) and im( a) < im(r) < im(b) for (a, b), r in zip(complex_part, nroots(f))) assert complex_part == [(Rational(-40, 7) - I*Rational(40, 7), 0), (Rational(-40, 7), I*Rational(40, 7)), (I*Rational(-40, 7), Rational(40, 7)), (0, Rational(40, 7) + I*Rational(40, 7))] real_part, complex_part = intervals(f, all=True, sqf=True, eps=Rational(1, 10)) assert real_part == [] assert all(re(a) < re(r) < re(b) and im( a) < im(r) < im(b) for (a, b), r in zip(complex_part, nroots(f))) raises(ValueError, lambda: intervals(x**2 - 2, eps=10**-100000)) raises(ValueError, lambda: Poly(x**2 - 2).intervals(eps=10**-100000)) raises( ValueError, lambda: intervals([x**2 - 2, x**2 - 3], eps=10**-100000)) def test_refine_root(): f = Poly(x**2 - 2) assert f.refine_root(1, 2, steps=0) == (1, 2) assert f.refine_root(-2, -1, steps=0) == (-2, -1) assert f.refine_root(1, 2, steps=None) == (1, Rational(3, 2)) assert f.refine_root(-2, -1, steps=None) == (Rational(-3, 2), -1) assert f.refine_root(1, 2, steps=1) == (1, Rational(3, 2)) assert f.refine_root(-2, -1, steps=1) == (Rational(-3, 2), -1) assert f.refine_root(1, 2, steps=1, fast=True) == (1, Rational(3, 2)) assert f.refine_root(-2, -1, steps=1, fast=True) == (Rational(-3, 2), -1) assert f.refine_root(1, 2, eps=Rational(1, 100)) == (Rational(24, 17), Rational(17, 12)) assert f.refine_root(1, 2, eps=1e-2) == (Rational(24, 17), Rational(17, 12)) raises(PolynomialError, lambda: (f**2).refine_root(1, 2, check_sqf=True)) raises(RefinementFailed, lambda: (f**2).refine_root(1, 2)) raises(RefinementFailed, lambda: (f**2).refine_root(2, 3)) f = x**2 - 2 assert refine_root(f, 1, 2, steps=1) == (1, Rational(3, 2)) assert refine_root(f, -2, -1, steps=1) == (Rational(-3, 2), -1) assert refine_root(f, 1, 2, steps=1, fast=True) == (1, Rational(3, 2)) assert refine_root(f, -2, -1, steps=1, fast=True) == (Rational(-3, 2), -1) assert refine_root(f, 1, 2, eps=Rational(1, 100)) == (Rational(24, 17), Rational(17, 12)) assert refine_root(f, 1, 2, eps=1e-2) == (Rational(24, 17), Rational(17, 12)) raises(PolynomialError, lambda: refine_root(1, 7, 8, eps=Rational(1, 100))) raises(ValueError, lambda: Poly(f).refine_root(1, 2, eps=10**-100000)) raises(ValueError, lambda: refine_root(f, 1, 2, eps=10**-100000)) def test_count_roots(): assert count_roots(x**2 - 2) == 2 assert count_roots(x**2 - 2, inf=-oo) == 2 assert count_roots(x**2 - 2, sup=+oo) == 2 assert count_roots(x**2 - 2, inf=-oo, sup=+oo) == 2 assert count_roots(x**2 - 2, inf=-2) == 2 assert count_roots(x**2 - 2, inf=-1) == 1 assert count_roots(x**2 - 2, sup=1) == 1 assert count_roots(x**2 - 2, sup=2) == 2 assert count_roots(x**2 - 2, inf=-1, sup=1) == 0 assert count_roots(x**2 - 2, inf=-2, sup=2) == 2 assert count_roots(x**2 - 2, inf=-1, sup=1) == 0 assert count_roots(x**2 - 2, inf=-2, sup=2) == 2 assert count_roots(x**2 + 2) == 0 assert count_roots(x**2 + 2, inf=-2*I) == 2 assert count_roots(x**2 + 2, sup=+2*I) == 2 assert count_roots(x**2 + 2, inf=-2*I, sup=+2*I) == 2 assert count_roots(x**2 + 2, inf=0) == 0 assert count_roots(x**2 + 2, sup=0) == 0 assert count_roots(x**2 + 2, inf=-I) == 1 assert count_roots(x**2 + 2, sup=+I) == 1 assert count_roots(x**2 + 2, inf=+I/2, sup=+I) == 0 assert count_roots(x**2 + 2, inf=-I, sup=-I/2) == 0 raises(PolynomialError, lambda: count_roots(1)) def test_Poly_root(): f = Poly(2*x**3 - 7*x**2 + 4*x + 4) assert f.root(0) == Rational(-1, 2) assert f.root(1) == 2 assert f.root(2) == 2 raises(IndexError, lambda: f.root(3)) assert Poly(x**5 + x + 1).root(0) == rootof(x**3 - x**2 + 1, 0) def test_real_roots(): assert real_roots(x) == [0] assert real_roots(x, multiple=False) == [(0, 1)] assert real_roots(x**3) == [0, 0, 0] assert real_roots(x**3, multiple=False) == [(0, 3)] assert real_roots(x*(x**3 + x + 3)) == [rootof(x**3 + x + 3, 0), 0] assert real_roots(x*(x**3 + x + 3), multiple=False) == [(rootof( x**3 + x + 3, 0), 1), (0, 1)] assert real_roots( x**3*(x**3 + x + 3)) == [rootof(x**3 + x + 3, 0), 0, 0, 0] assert real_roots(x**3*(x**3 + x + 3), multiple=False) == [(rootof( x**3 + x + 3, 0), 1), (0, 3)] f = 2*x**3 - 7*x**2 + 4*x + 4 g = x**3 + x + 1 assert Poly(f).real_roots() == [Rational(-1, 2), 2, 2] assert Poly(g).real_roots() == [rootof(g, 0)] def test_all_roots(): f = 2*x**3 - 7*x**2 + 4*x + 4 g = x**3 + x + 1 assert Poly(f).all_roots() == [Rational(-1, 2), 2, 2] assert Poly(g).all_roots() == [rootof(g, 0), rootof(g, 1), rootof(g, 2)] def test_nroots(): assert Poly(0, x).nroots() == [] assert Poly(1, x).nroots() == [] assert Poly(x**2 - 1, x).nroots() == [-1.0, 1.0] assert Poly(x**2 + 1, x).nroots() == [-1.0*I, 1.0*I] roots = Poly(x**2 - 1, x).nroots() assert roots == [-1.0, 1.0] roots = Poly(x**2 + 1, x).nroots() assert roots == [-1.0*I, 1.0*I] roots = Poly(x**2/3 - Rational(1, 3), x).nroots() assert roots == [-1.0, 1.0] roots = Poly(x**2/3 + Rational(1, 3), x).nroots() assert roots == [-1.0*I, 1.0*I] assert Poly(x**2 + 2*I, x).nroots() == [-1.0 + 1.0*I, 1.0 - 1.0*I] assert Poly( x**2 + 2*I, x, extension=I).nroots() == [-1.0 + 1.0*I, 1.0 - 1.0*I] assert Poly(0.2*x + 0.1).nroots() == [-0.5] roots = nroots(x**5 + x + 1, n=5) eps = Float("1e-5") assert re(roots[0]).epsilon_eq(-0.75487, eps) is S.true assert im(roots[0]) == 0.0 assert re(roots[1]) == -0.5 assert im(roots[1]).epsilon_eq(-0.86602, eps) is S.true assert re(roots[2]) == -0.5 assert im(roots[2]).epsilon_eq(+0.86602, eps) is S.true assert re(roots[3]).epsilon_eq(+0.87743, eps) is S.true assert im(roots[3]).epsilon_eq(-0.74486, eps) is S.true assert re(roots[4]).epsilon_eq(+0.87743, eps) is S.true assert im(roots[4]).epsilon_eq(+0.74486, eps) is S.true eps = Float("1e-6") assert re(roots[0]).epsilon_eq(-0.75487, eps) is S.false assert im(roots[0]) == 0.0 assert re(roots[1]) == -0.5 assert im(roots[1]).epsilon_eq(-0.86602, eps) is S.false assert re(roots[2]) == -0.5 assert im(roots[2]).epsilon_eq(+0.86602, eps) is S.false assert re(roots[3]).epsilon_eq(+0.87743, eps) is S.false assert im(roots[3]).epsilon_eq(-0.74486, eps) is S.false assert re(roots[4]).epsilon_eq(+0.87743, eps) is S.false assert im(roots[4]).epsilon_eq(+0.74486, eps) is S.false raises(DomainError, lambda: Poly(x + y, x).nroots()) raises(MultivariatePolynomialError, lambda: Poly(x + y).nroots()) assert nroots(x**2 - 1) == [-1.0, 1.0] roots = nroots(x**2 - 1) assert roots == [-1.0, 1.0] assert nroots(x + I) == [-1.0*I] assert nroots(x + 2*I) == [-2.0*I] raises(PolynomialError, lambda: nroots(0)) # issue 8296 f = Poly(x**4 - 1) assert f.nroots(2) == [w.n(2) for w in f.all_roots()] assert str(Poly(x**16 + 32*x**14 + 508*x**12 + 5440*x**10 + 39510*x**8 + 204320*x**6 + 755548*x**4 + 1434496*x**2 + 877969).nroots(2)) == ('[-1.7 - 1.9*I, -1.7 + 1.9*I, -1.7 ' '- 2.5*I, -1.7 + 2.5*I, -1.0*I, 1.0*I, -1.7*I, 1.7*I, -2.8*I, ' '2.8*I, -3.4*I, 3.4*I, 1.7 - 1.9*I, 1.7 + 1.9*I, 1.7 - 2.5*I, ' '1.7 + 2.5*I]') def test_ground_roots(): f = x**6 - 4*x**4 + 4*x**3 - x**2 assert Poly(f).ground_roots() == {S.One: 2, S.Zero: 2} assert ground_roots(f) == {S.One: 2, S.Zero: 2} def test_nth_power_roots_poly(): f = x**4 - x**2 + 1 f_2 = (x**2 - x + 1)**2 f_3 = (x**2 + 1)**2 f_4 = (x**2 + x + 1)**2 f_12 = (x - 1)**4 assert nth_power_roots_poly(f, 1) == f raises(ValueError, lambda: nth_power_roots_poly(f, 0)) raises(ValueError, lambda: nth_power_roots_poly(f, x)) assert factor(nth_power_roots_poly(f, 2)) == f_2 assert factor(nth_power_roots_poly(f, 3)) == f_3 assert factor(nth_power_roots_poly(f, 4)) == f_4 assert factor(nth_power_roots_poly(f, 12)) == f_12 raises(MultivariatePolynomialError, lambda: nth_power_roots_poly( x + y, 2, x, y)) def test_torational_factor_list(): p = expand(((x**2-1)*(x-2)).subs({x:x*(1 + sqrt(2))})) assert _torational_factor_list(p, x) == (-2, [ (-x*(1 + sqrt(2))/2 + 1, 1), (-x*(1 + sqrt(2)) - 1, 1), (-x*(1 + sqrt(2)) + 1, 1)]) p = expand(((x**2-1)*(x-2)).subs({x:x*(1 + 2**Rational(1, 4))})) assert _torational_factor_list(p, x) is None def test_cancel(): assert cancel(0) == 0 assert cancel(7) == 7 assert cancel(x) == x assert cancel(oo) is oo assert cancel((2, 3)) == (1, 2, 3) assert cancel((1, 0), x) == (1, 1, 0) assert cancel((0, 1), x) == (1, 0, 1) f, g, p, q = 4*x**2 - 4, 2*x - 2, 2*x + 2, 1 F, G, P, Q = [ Poly(u, x) for u in (f, g, p, q) ] assert F.cancel(G) == (1, P, Q) assert cancel((f, g)) == (1, p, q) assert cancel((f, g), x) == (1, p, q) assert cancel((f, g), (x,)) == (1, p, q) assert cancel((F, G)) == (1, P, Q) assert cancel((f, g), polys=True) == (1, P, Q) assert cancel((F, G), polys=False) == (1, p, q) f = (x**2 - 2)/(x + sqrt(2)) assert cancel(f) == f assert cancel(f, greedy=False) == x - sqrt(2) f = (x**2 - 2)/(x - sqrt(2)) assert cancel(f) == f assert cancel(f, greedy=False) == x + sqrt(2) assert cancel((x**2/4 - 1, x/2 - 1)) == (1, x + 2, 2) # assert cancel((x**2/4 - 1, x/2 - 1)) == (S.Half, x + 2, 1) assert cancel((x**2 - y)/(x - y)) == 1/(x - y)*(x**2 - y) assert cancel((x**2 - y**2)/(x - y), x) == x + y assert cancel((x**2 - y**2)/(x - y), y) == x + y assert cancel((x**2 - y**2)/(x - y)) == x + y assert cancel((x**3 - 1)/(x**2 - 1)) == (x**2 + x + 1)/(x + 1) assert cancel((x**3/2 - S.Half)/(x**2 - 1)) == (x**2 + x + 1)/(2*x + 2) assert cancel((exp(2*x) + 2*exp(x) + 1)/(exp(x) + 1)) == exp(x) + 1 f = Poly(x**2 - a**2, x) g = Poly(x - a, x) F = Poly(x + a, x, domain='ZZ[a]') G = Poly(1, x, domain='ZZ[a]') assert cancel((f, g)) == (1, F, G) f = x**3 + (sqrt(2) - 2)*x**2 - (2*sqrt(2) + 3)*x - 3*sqrt(2) g = x**2 - 2 assert cancel((f, g), extension=True) == (1, x**2 - 2*x - 3, x - sqrt(2)) f = Poly(-2*x + 3, x) g = Poly(-x**9 + x**8 + x**6 - x**5 + 2*x**2 - 3*x + 1, x) assert cancel((f, g)) == (1, -f, -g) f = Poly(y, y, domain='ZZ(x)') g = Poly(1, y, domain='ZZ[x]') assert f.cancel( g) == (1, Poly(y, y, domain='ZZ(x)'), Poly(1, y, domain='ZZ(x)')) assert f.cancel(g, include=True) == ( Poly(y, y, domain='ZZ(x)'), Poly(1, y, domain='ZZ(x)')) f = Poly(5*x*y + x, y, domain='ZZ(x)') g = Poly(2*x**2*y, y, domain='ZZ(x)') assert f.cancel(g, include=True) == ( Poly(5*y + 1, y, domain='ZZ(x)'), Poly(2*x*y, y, domain='ZZ(x)')) f = -(-2*x - 4*y + 0.005*(z - y)**2)/((z - y)*(-z + y + 2)) assert cancel(f).is_Mul == True P = tanh(x - 3.0) Q = tanh(x + 3.0) f = ((-2*P**2 + 2)*(-P**2 + 1)*Q**2/2 + (-2*P**2 + 2)*(-2*Q**2 + 2)*P*Q - (-2*P**2 + 2)*P**2*Q**2 + (-2*Q**2 + 2)*(-Q**2 + 1)*P**2/2 - (-2*Q**2 + 2)*P**2*Q**2)/(2*sqrt(P**2*Q**2 + 0.0001)) \ + (-(-2*P**2 + 2)*P*Q**2/2 - (-2*Q**2 + 2)*P**2*Q/2)*((-2*P**2 + 2)*P*Q**2/2 + (-2*Q**2 + 2)*P**2*Q/2)/(2*(P**2*Q**2 + 0.0001)**Rational(3, 2)) assert cancel(f).is_Mul == True # issue 7022 A = Symbol('A', commutative=False) p1 = Piecewise((A*(x**2 - 1)/(x + 1), x > 1), ((x + 2)/(x**2 + 2*x), True)) p2 = Piecewise((A*(x - 1), x > 1), (1/x, True)) assert cancel(p1) == p2 assert cancel(2*p1) == 2*p2 assert cancel(1 + p1) == 1 + p2 assert cancel((x**2 - 1)/(x + 1)*p1) == (x - 1)*p2 assert cancel((x**2 - 1)/(x + 1) + p1) == (x - 1) + p2 p3 = Piecewise(((x**2 - 1)/(x + 1), x > 1), ((x + 2)/(x**2 + 2*x), True)) p4 = Piecewise(((x - 1), x > 1), (1/x, True)) assert cancel(p3) == p4 assert cancel(2*p3) == 2*p4 assert cancel(1 + p3) == 1 + p4 assert cancel((x**2 - 1)/(x + 1)*p3) == (x - 1)*p4 assert cancel((x**2 - 1)/(x + 1) + p3) == (x - 1) + p4 # issue 9363 M = MatrixSymbol('M', 5, 5) assert cancel(M[0,0] + 7) == M[0,0] + 7 expr = sin(M[1, 4] + M[2, 1] * 5 * M[4, 0]) - 5 * M[1, 2] / z assert cancel(expr) == (z*sin(M[1, 4] + M[2, 1] * 5 * M[4, 0]) - 5 * M[1, 2]) / z assert cancel((x**2 + 1)/(x - I)) == x + I def test_reduced(): f = 2*x**4 + y**2 - x**2 + y**3 G = [x**3 - x, y**3 - y] Q = [2*x, 1] r = x**2 + y**2 + y assert reduced(f, G) == (Q, r) assert reduced(f, G, x, y) == (Q, r) H = groebner(G) assert H.reduce(f) == (Q, r) Q = [Poly(2*x, x, y), Poly(1, x, y)] r = Poly(x**2 + y**2 + y, x, y) assert _strict_eq(reduced(f, G, polys=True), (Q, r)) assert _strict_eq(reduced(f, G, x, y, polys=True), (Q, r)) H = groebner(G, polys=True) assert _strict_eq(H.reduce(f), (Q, r)) f = 2*x**3 + y**3 + 3*y G = groebner([x**2 + y**2 - 1, x*y - 2]) Q = [x**2 - x*y**3/2 + x*y/2 + y**6/4 - y**4/2 + y**2/4, -y**5/4 + y**3/2 + y*Rational(3, 4)] r = 0 assert reduced(f, G) == (Q, r) assert G.reduce(f) == (Q, r) assert reduced(f, G, auto=False)[1] != 0 assert G.reduce(f, auto=False)[1] != 0 assert G.contains(f) is True assert G.contains(f + 1) is False assert reduced(1, [1], x) == ([1], 0) raises(ComputationFailed, lambda: reduced(1, [1])) def test_groebner(): assert groebner([], x, y, z) == [] assert groebner([x**2 + 1, y**4*x + x**3], x, y, order='lex') == [1 + x**2, -1 + y**4] assert groebner([x**2 + 1, y**4*x + x**3, x*y*z**3], x, y, z, order='grevlex') == [-1 + y**4, z**3, 1 + x**2] assert groebner([x**2 + 1, y**4*x + x**3], x, y, order='lex', polys=True) == \ [Poly(1 + x**2, x, y), Poly(-1 + y**4, x, y)] assert groebner([x**2 + 1, y**4*x + x**3, x*y*z**3], x, y, z, order='grevlex', polys=True) == \ [Poly(-1 + y**4, x, y, z), Poly(z**3, x, y, z), Poly(1 + x**2, x, y, z)] assert groebner([x**3 - 1, x**2 - 1]) == [x - 1] assert groebner([Eq(x**3, 1), Eq(x**2, 1)]) == [x - 1] F = [3*x**2 + y*z - 5*x - 1, 2*x + 3*x*y + y**2, x - 3*y + x*z - 2*z**2] f = z**9 - x**2*y**3 - 3*x*y**2*z + 11*y*z**2 + x**2*z**2 - 5 G = groebner(F, x, y, z, modulus=7, symmetric=False) assert G == [1 + x + y + 3*z + 2*z**2 + 2*z**3 + 6*z**4 + z**5, 1 + 3*y + y**2 + 6*z**2 + 3*z**3 + 3*z**4 + 3*z**5 + 4*z**6, 1 + 4*y + 4*z + y*z + 4*z**3 + z**4 + z**6, 6 + 6*z + z**2 + 4*z**3 + 3*z**4 + 6*z**5 + 3*z**6 + z**7] Q, r = reduced(f, G, x, y, z, modulus=7, symmetric=False, polys=True) assert sum([ q*g for q, g in zip(Q, G.polys)], r) == Poly(f, modulus=7) F = [x*y - 2*y, 2*y**2 - x**2] assert groebner(F, x, y, order='grevlex') == \ [y**3 - 2*y, x**2 - 2*y**2, x*y - 2*y] assert groebner(F, y, x, order='grevlex') == \ [x**3 - 2*x**2, -x**2 + 2*y**2, x*y - 2*y] assert groebner(F, order='grevlex', field=True) == \ [y**3 - 2*y, x**2 - 2*y**2, x*y - 2*y] assert groebner([1], x) == [1] assert groebner([x**2 + 2.0*y], x, y) == [1.0*x**2 + 2.0*y] raises(ComputationFailed, lambda: groebner([1])) assert groebner([x**2 - 1, x**3 + 1], method='buchberger') == [x + 1] assert groebner([x**2 - 1, x**3 + 1], method='f5b') == [x + 1] raises(ValueError, lambda: groebner([x, y], method='unknown')) def test_fglm(): F = [a + b + c + d, a*b + a*d + b*c + b*d, a*b*c + a*b*d + a*c*d + b*c*d, a*b*c*d - 1] G = groebner(F, a, b, c, d, order=grlex) B = [ 4*a + 3*d**9 - 4*d**5 - 3*d, 4*b + 4*c - 3*d**9 + 4*d**5 + 7*d, 4*c**2 + 3*d**10 - 4*d**6 - 3*d**2, 4*c*d**4 + 4*c - d**9 + 4*d**5 + 5*d, d**12 - d**8 - d**4 + 1, ] assert groebner(F, a, b, c, d, order=lex) == B assert G.fglm(lex) == B F = [9*x**8 + 36*x**7 - 32*x**6 - 252*x**5 - 78*x**4 + 468*x**3 + 288*x**2 - 108*x + 9, -72*t*x**7 - 252*t*x**6 + 192*t*x**5 + 1260*t*x**4 + 312*t*x**3 - 404*t*x**2 - 576*t*x + \ 108*t - 72*x**7 - 256*x**6 + 192*x**5 + 1280*x**4 + 312*x**3 - 576*x + 96] G = groebner(F, t, x, order=grlex) B = [ 203577793572507451707*t + 627982239411707112*x**7 - 666924143779443762*x**6 - \ 10874593056632447619*x**5 + 5119998792707079562*x**4 + 72917161949456066376*x**3 + \ 20362663855832380362*x**2 - 142079311455258371571*x + 183756699868981873194, 9*x**8 + 36*x**7 - 32*x**6 - 252*x**5 - 78*x**4 + 468*x**3 + 288*x**2 - 108*x + 9, ] assert groebner(F, t, x, order=lex) == B assert G.fglm(lex) == B F = [x**2 - x - 3*y + 1, -2*x + y**2 + y - 1] G = groebner(F, x, y, order=lex) B = [ x**2 - x - 3*y + 1, y**2 - 2*x + y - 1, ] assert groebner(F, x, y, order=grlex) == B assert G.fglm(grlex) == B def test_is_zero_dimensional(): assert is_zero_dimensional([x, y], x, y) is True assert is_zero_dimensional([x**3 + y**2], x, y) is False assert is_zero_dimensional([x, y, z], x, y, z) is True assert is_zero_dimensional([x, y, z], x, y, z, t) is False F = [x*y - z, y*z - x, x*y - y] assert is_zero_dimensional(F, x, y, z) is True F = [x**2 - 2*x*z + 5, x*y**2 + y*z**3, 3*y**2 - 8*z**2] assert is_zero_dimensional(F, x, y, z) is True def test_GroebnerBasis(): F = [x*y - 2*y, 2*y**2 - x**2] G = groebner(F, x, y, order='grevlex') H = [y**3 - 2*y, x**2 - 2*y**2, x*y - 2*y] P = [ Poly(h, x, y) for h in H ] assert groebner(F + [0], x, y, order='grevlex') == G assert isinstance(G, GroebnerBasis) is True assert len(G) == 3 assert G[0] == H[0] and not G[0].is_Poly assert G[1] == H[1] and not G[1].is_Poly assert G[2] == H[2] and not G[2].is_Poly assert G[1:] == H[1:] and not any(g.is_Poly for g in G[1:]) assert G[:2] == H[:2] and not any(g.is_Poly for g in G[1:]) assert G.exprs == H assert G.polys == P assert G.gens == (x, y) assert G.domain == ZZ assert G.order == grevlex assert G == H assert G == tuple(H) assert G == P assert G == tuple(P) assert G != [] G = groebner(F, x, y, order='grevlex', polys=True) assert G[0] == P[0] and G[0].is_Poly assert G[1] == P[1] and G[1].is_Poly assert G[2] == P[2] and G[2].is_Poly assert G[1:] == P[1:] and all(g.is_Poly for g in G[1:]) assert G[:2] == P[:2] and all(g.is_Poly for g in G[1:]) def test_poly(): assert poly(x) == Poly(x, x) assert poly(y) == Poly(y, y) assert poly(x + y) == Poly(x + y, x, y) assert poly(x + sin(x)) == Poly(x + sin(x), x, sin(x)) assert poly(x + y, wrt=y) == Poly(x + y, y, x) assert poly(x + sin(x), wrt=sin(x)) == Poly(x + sin(x), sin(x), x) assert poly(x*y + 2*x*z**2 + 17) == Poly(x*y + 2*x*z**2 + 17, x, y, z) assert poly(2*(y + z)**2 - 1) == Poly(2*y**2 + 4*y*z + 2*z**2 - 1, y, z) assert poly( x*(y + z)**2 - 1) == Poly(x*y**2 + 2*x*y*z + x*z**2 - 1, x, y, z) assert poly(2*x*( y + z)**2 - 1) == Poly(2*x*y**2 + 4*x*y*z + 2*x*z**2 - 1, x, y, z) assert poly(2*( y + z)**2 - x - 1) == Poly(2*y**2 + 4*y*z + 2*z**2 - x - 1, x, y, z) assert poly(x*( y + z)**2 - x - 1) == Poly(x*y**2 + 2*x*y*z + x*z**2 - x - 1, x, y, z) assert poly(2*x*(y + z)**2 - x - 1) == Poly(2*x*y**2 + 4*x*y*z + 2* x*z**2 - x - 1, x, y, z) assert poly(x*y + (x + y)**2 + (x + z)**2) == \ Poly(2*x*z + 3*x*y + y**2 + z**2 + 2*x**2, x, y, z) assert poly(x*y*(x + y)*(x + z)**2) == \ Poly(x**3*y**2 + x*y**2*z**2 + y*x**2*z**2 + 2*z*x**2* y**2 + 2*y*z*x**3 + y*x**4, x, y, z) assert poly(Poly(x + y + z, y, x, z)) == Poly(x + y + z, y, x, z) assert poly((x + y)**2, x) == Poly(x**2 + 2*x*y + y**2, x, domain=ZZ[y]) assert poly((x + y)**2, y) == Poly(x**2 + 2*x*y + y**2, y, domain=ZZ[x]) assert poly(1, x) == Poly(1, x) raises(GeneratorsNeeded, lambda: poly(1)) # issue 6184 assert poly(x + y, x, y) == Poly(x + y, x, y) assert poly(x + y, y, x) == Poly(x + y, y, x) def test_keep_coeff(): u = Mul(2, x + 1, evaluate=False) assert _keep_coeff(S.One, x) == x assert _keep_coeff(S.NegativeOne, x) == -x assert _keep_coeff(S(1.0), x) == 1.0*x assert _keep_coeff(S(-1.0), x) == -1.0*x assert _keep_coeff(S.One, 2*x) == 2*x assert _keep_coeff(S(2), x/2) == x assert _keep_coeff(S(2), sin(x)) == 2*sin(x) assert _keep_coeff(S(2), x + 1) == u assert _keep_coeff(x, 1/x) == 1 assert _keep_coeff(x + 1, S(2)) == u assert _keep_coeff(S.Half, S.One) == S.Half p = Pow(2, 3, evaluate=False) assert _keep_coeff(S(-1), p) == Mul(-1, p, evaluate=False) a = Add(2, p, evaluate=False) assert _keep_coeff(S.Half, a, clear=True ) == Mul(S.Half, a, evaluate=False) assert _keep_coeff(S.Half, a, clear=False ) == Add(1, Mul(S.Half, p, evaluate=False), evaluate=False) def test_poly_matching_consistency(): # Test for this issue: # https://github.com/sympy/sympy/issues/5514 assert I * Poly(x, x) == Poly(I*x, x) assert Poly(x, x) * I == Poly(I*x, x) def test_issue_5786(): assert expand(factor(expand( (x - I*y)*(z - I*t)), extension=[I])) == -I*t*x - t*y + x*z - I*y*z def test_noncommutative(): class foo(Expr): is_commutative=False e = x/(x + x*y) c = 1/( 1 + y) assert cancel(foo(e)) == foo(c) assert cancel(e + foo(e)) == c + foo(c) assert cancel(e*foo(c)) == c*foo(c) def test_to_rational_coeffs(): assert to_rational_coeffs( Poly(x**3 + y*x**2 + sqrt(y), x, domain='EX')) is None # issue 21268 assert to_rational_coeffs( Poly(y**3 + sqrt(2)*y**2*sin(x) + 1, y)) is None assert to_rational_coeffs(Poly(x, y)) is None assert to_rational_coeffs(Poly(sqrt(2)*y)) is None def test_factor_terms(): # issue 7067 assert factor_list(x*(x + y)) == (1, [(x, 1), (x + y, 1)]) assert sqf_list(x*(x + y)) == (1, [(x**2 + x*y, 1)]) def test_as_list(): # issue 14496 assert Poly(x**3 + 2, x, domain='ZZ').as_list() == [1, 0, 0, 2] assert Poly(x**2 + y + 1, x, y, domain='ZZ').as_list() == [[1], [], [1, 1]] assert Poly(x**2 + y + 1, x, y, z, domain='ZZ').as_list() == \ [[[1]], [[]], [[1], [1]]] def test_issue_11198(): assert factor_list(sqrt(2)*x) == (sqrt(2), [(x, 1)]) assert factor_list(sqrt(2)*sin(x), sin(x)) == (sqrt(2), [(sin(x), 1)]) def test_Poly_precision(): # Make sure Poly doesn't lose precision p = Poly(pi.evalf(100)*x) assert p.as_expr() == pi.evalf(100)*x def test_issue_12400(): # Correction of check for negative exponents assert poly(1/(1+sqrt(2)), x) == \ Poly(1/(1+sqrt(2)), x , domain='EX') def test_issue_14364(): assert gcd(S(6)*(1 + sqrt(3))/5, S(3)*(1 + sqrt(3))/10) == Rational(3, 10) * (1 + sqrt(3)) assert gcd(sqrt(5)*Rational(4, 7), sqrt(5)*Rational(2, 3)) == sqrt(5)*Rational(2, 21) assert lcm(Rational(2, 3)*sqrt(3), Rational(5, 6)*sqrt(3)) == S(10)*sqrt(3)/3 assert lcm(3*sqrt(3), 4/sqrt(3)) == 12*sqrt(3) assert lcm(S(5)*(1 + 2**Rational(1, 3))/6, S(3)*(1 + 2**Rational(1, 3))/8) == Rational(15, 2) * (1 + 2**Rational(1, 3)) assert gcd(Rational(2, 3)*sqrt(3), Rational(5, 6)/sqrt(3)) == sqrt(3)/18 assert gcd(S(4)*sqrt(13)/7, S(3)*sqrt(13)/14) == sqrt(13)/14 # gcd_list and lcm_list assert gcd([S(2)*sqrt(47)/7, S(6)*sqrt(47)/5, S(8)*sqrt(47)/5]) == sqrt(47)*Rational(2, 35) assert gcd([S(6)*(1 + sqrt(7))/5, S(2)*(1 + sqrt(7))/7, S(4)*(1 + sqrt(7))/13]) == (1 + sqrt(7))*Rational(2, 455) assert lcm((Rational(7, 2)/sqrt(15), Rational(5, 6)/sqrt(15), Rational(5, 8)/sqrt(15))) == Rational(35, 2)/sqrt(15) assert lcm([S(5)*(2 + 2**Rational(5, 7))/6, S(7)*(2 + 2**Rational(5, 7))/2, S(13)*(2 + 2**Rational(5, 7))/4]) == Rational(455, 2) * (2 + 2**Rational(5, 7)) def test_issue_15669(): x = Symbol("x", positive=True) expr = (16*x**3/(-x**2 + sqrt(8*x**2 + (x**2 - 2)**2) + 2)**2 - 2*2**Rational(4, 5)*x*(-x**2 + sqrt(8*x**2 + (x**2 - 2)**2) + 2)**Rational(3, 5) + 10*x) assert factor(expr, deep=True) == x*(x**2 + 2) def test_issue_17988(): x = Symbol('x') p = poly(x - 1) with warns_deprecated_sympy(): M = Matrix([[poly(x + 1), poly(x + 1)]]) with warns_deprecated_sympy(): assert p * M == M * p == Matrix([[poly(x**2 - 1), poly(x**2 - 1)]]) def test_issue_18205(): assert cancel((2 + I)*(3 - I)) == 7 + I assert cancel((2 + I)*(2 - I)) == 5 def test_issue_8695(): p = (x**2 + 1) * (x - 1)**2 * (x - 2)**3 * (x - 3)**3 result = (1, [(x**2 + 1, 1), (x - 1, 2), (x**2 - 5*x + 6, 3)]) assert sqf_list(p) == result def test_issue_19113(): eq = sin(x)**3 - sin(x) + 1 raises(PolynomialError, lambda: refine_root(eq, 1, 2, 1e-2)) raises(PolynomialError, lambda: count_roots(eq, -1, 1)) raises(PolynomialError, lambda: real_roots(eq)) raises(PolynomialError, lambda: nroots(eq)) raises(PolynomialError, lambda: ground_roots(eq)) raises(PolynomialError, lambda: nth_power_roots_poly(eq, 2)) def test_issue_19360(): f = 2*x**2 - 2*sqrt(2)*x*y + y**2 assert factor(f, extension=sqrt(2)) == 2*(x - (sqrt(2)*y/2))**2 f = -I*t*x - t*y + x*z - I*y*z assert factor(f, extension=I) == (x - I*y)*(-I*t + z) def test_poly_copy_equals_original(): poly = Poly(x + y, x, y, z) copy = poly.copy() assert poly == copy, ( "Copied polynomial not equal to original.") assert poly.gens == copy.gens, ( "Copied polynomial has different generators than original.") def test_deserialized_poly_equals_original(): poly = Poly(x + y, x, y, z) deserialized = pickle.loads(pickle.dumps(poly)) assert poly == deserialized, ( "Deserialized polynomial not equal to original.") assert poly.gens == deserialized.gens, ( "Deserialized polynomial has different generators than original.") def test_issue_20389(): result = degree(x * (x + 1) - x ** 2 - x, x) assert result == -oo def test_issue_20985(): from sympy import symbols w, R = symbols('w R') poly = Poly(1.0 + I*w/R, w, 1/R) assert poly.degree() == S(1)
cb032f330153ac292600ae5077148930e813359c10811a6513d133f7fa5249d2
"""Tests for OO layer of several polynomial representations. """ from sympy.polys.domains import ZZ, QQ from sympy.polys.polyclasses import DMP, DMF, ANP from sympy.polys.polyerrors import ExactQuotientFailed, NotInvertible from sympy.polys.specialpolys import f_polys from sympy.testing.pytest import raises f_0, f_1, f_2, f_3, f_4, f_5, f_6 = [ f.to_dense() for f in f_polys() ] def test_DMP___init__(): f = DMP([[0], [], [0, 1, 2], [3]], ZZ) assert f.rep == [[1, 2], [3]] assert f.dom == ZZ assert f.lev == 1 f = DMP([[1, 2], [3]], ZZ, 1) assert f.rep == [[1, 2], [3]] assert f.dom == ZZ assert f.lev == 1 f = DMP({(1, 1): 1, (0, 0): 2}, ZZ, 1) assert f.rep == [[1, 0], [2]] assert f.dom == ZZ assert f.lev == 1 def test_DMP___eq__(): assert DMP([[ZZ(1), ZZ(2)], [ZZ(3)]], ZZ) == \ DMP([[ZZ(1), ZZ(2)], [ZZ(3)]], ZZ) assert DMP([[ZZ(1), ZZ(2)], [ZZ(3)]], ZZ) == \ DMP([[QQ(1), QQ(2)], [QQ(3)]], QQ) assert DMP([[QQ(1), QQ(2)], [QQ(3)]], QQ) == \ DMP([[ZZ(1), ZZ(2)], [ZZ(3)]], ZZ) assert DMP([[[ZZ(1)]]], ZZ) != DMP([[ZZ(1)]], ZZ) assert DMP([[ZZ(1)]], ZZ) != DMP([[[ZZ(1)]]], ZZ) def test_DMP___bool__(): assert bool(DMP([[]], ZZ)) is False assert bool(DMP([[1]], ZZ)) is True def test_DMP_to_dict(): f = DMP([[3], [], [2], [], [8]], ZZ) assert f.to_dict() == \ {(4, 0): 3, (2, 0): 2, (0, 0): 8} assert f.to_sympy_dict() == \ {(4, 0): ZZ.to_sympy(3), (2, 0): ZZ.to_sympy(2), (0, 0): ZZ.to_sympy(8)} def test_DMP_properties(): assert DMP([[]], ZZ).is_zero is True assert DMP([[1]], ZZ).is_zero is False assert DMP([[1]], ZZ).is_one is True assert DMP([[2]], ZZ).is_one is False assert DMP([[1]], ZZ).is_ground is True assert DMP([[1], [2], [1]], ZZ).is_ground is False assert DMP([[1], [2, 0], [1, 0]], ZZ).is_sqf is True assert DMP([[1], [2, 0], [1, 0, 0]], ZZ).is_sqf is False assert DMP([[1, 2], [3]], ZZ).is_monic is True assert DMP([[2, 2], [3]], ZZ).is_monic is False assert DMP([[1, 2], [3]], ZZ).is_primitive is True assert DMP([[2, 4], [6]], ZZ).is_primitive is False def test_DMP_arithmetics(): f = DMP([[2], [2, 0]], ZZ) assert f.mul_ground(2) == DMP([[4], [4, 0]], ZZ) assert f.quo_ground(2) == DMP([[1], [1, 0]], ZZ) raises(ExactQuotientFailed, lambda: f.exquo_ground(3)) f = DMP([[-5]], ZZ) g = DMP([[5]], ZZ) assert f.abs() == g assert abs(f) == g assert g.neg() == f assert -g == f h = DMP([[]], ZZ) assert f.add(g) == h assert f + g == h assert g + f == h assert f + 5 == h assert 5 + f == h h = DMP([[-10]], ZZ) assert f.sub(g) == h assert f - g == h assert g - f == -h assert f - 5 == h assert 5 - f == -h h = DMP([[-25]], ZZ) assert f.mul(g) == h assert f * g == h assert g * f == h assert f * 5 == h assert 5 * f == h h = DMP([[25]], ZZ) assert f.sqr() == h assert f.pow(2) == h assert f**2 == h raises(TypeError, lambda: f.pow('x')) f = DMP([[1], [], [1, 0, 0]], ZZ) g = DMP([[2], [-2, 0]], ZZ) q = DMP([[2], [2, 0]], ZZ) r = DMP([[8, 0, 0]], ZZ) assert f.pdiv(g) == (q, r) assert f.pquo(g) == q assert f.prem(g) == r raises(ExactQuotientFailed, lambda: f.pexquo(g)) f = DMP([[1], [], [1, 0, 0]], ZZ) g = DMP([[1], [-1, 0]], ZZ) q = DMP([[1], [1, 0]], ZZ) r = DMP([[2, 0, 0]], ZZ) assert f.div(g) == (q, r) assert f.quo(g) == q assert f.rem(g) == r assert divmod(f, g) == (q, r) assert f // g == q assert f % g == r raises(ExactQuotientFailed, lambda: f.exquo(g)) def test_DMP_functionality(): f = DMP([[1], [2, 0], [1, 0, 0]], ZZ) g = DMP([[1], [1, 0]], ZZ) h = DMP([[1]], ZZ) assert f.degree() == 2 assert f.degree_list() == (2, 2) assert f.total_degree() == 2 assert f.LC() == ZZ(1) assert f.TC() == ZZ(0) assert f.nth(1, 1) == ZZ(2) raises(TypeError, lambda: f.nth(0, 'x')) assert f.max_norm() == 2 assert f.l1_norm() == 4 u = DMP([[2], [2, 0]], ZZ) assert f.diff(m=1, j=0) == u assert f.diff(m=1, j=1) == u raises(TypeError, lambda: f.diff(m='x', j=0)) u = DMP([1, 2, 1], ZZ) v = DMP([1, 2, 1], ZZ) assert f.eval(a=1, j=0) == u assert f.eval(a=1, j=1) == v assert f.eval(1).eval(1) == ZZ(4) assert f.cofactors(g) == (g, g, h) assert f.gcd(g) == g assert f.lcm(g) == f u = DMP([[QQ(45), QQ(30), QQ(5)]], QQ) v = DMP([[QQ(1), QQ(2, 3), QQ(1, 9)]], QQ) assert u.monic() == v assert (4*f).content() == ZZ(4) assert (4*f).primitive() == (ZZ(4), f) f = DMP([[1], [2], [3], [4], [5], [6]], ZZ) assert f.trunc(3) == DMP([[1], [-1], [], [1], [-1], []], ZZ) f = DMP(f_4, ZZ) assert f.sqf_part() == -f assert f.sqf_list() == (ZZ(-1), [(-f, 1)]) f = DMP([[-1], [], [], [5]], ZZ) g = DMP([[3, 1], [], []], ZZ) h = DMP([[45, 30, 5]], ZZ) r = DMP([675, 675, 225, 25], ZZ) assert f.subresultants(g) == [f, g, h] assert f.resultant(g) == r f = DMP([1, 3, 9, -13], ZZ) assert f.discriminant() == -11664 f = DMP([QQ(2), QQ(0)], QQ) g = DMP([QQ(1), QQ(0), QQ(-16)], QQ) s = DMP([QQ(1, 32), QQ(0)], QQ) t = DMP([QQ(-1, 16)], QQ) h = DMP([QQ(1)], QQ) assert f.half_gcdex(g) == (s, h) assert f.gcdex(g) == (s, t, h) assert f.invert(g) == s f = DMP([[1], [2], [3]], QQ) raises(ValueError, lambda: f.half_gcdex(f)) raises(ValueError, lambda: f.gcdex(f)) raises(ValueError, lambda: f.invert(f)) f = DMP([1, 0, 20, 0, 150, 0, 500, 0, 625, -2, 0, -10, 9], ZZ) g = DMP([1, 0, 0, -2, 9], ZZ) h = DMP([1, 0, 5, 0], ZZ) assert g.compose(h) == f assert f.decompose() == [g, h] f = DMP([[1], [2], [3]], QQ) raises(ValueError, lambda: f.decompose()) raises(ValueError, lambda: f.sturm()) def test_DMP_exclude(): f = [[[[[[[[[[[[[[[[[[[[[[[[[[1]], [[]]]]]]]]]]]]]]]]]]]]]]]]]] J = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 24, 25] assert DMP(f, ZZ).exclude() == (J, DMP([1, 0], ZZ)) assert DMP([[1], [1, 0]], ZZ).exclude() == ([], DMP([[1], [1, 0]], ZZ)) def test_DMF__init__(): f = DMF(([[0], [], [0, 1, 2], [3]], [[1, 2, 3]]), ZZ) assert f.num == [[1, 2], [3]] assert f.den == [[1, 2, 3]] assert f.lev == 1 assert f.dom == ZZ f = DMF(([[1, 2], [3]], [[1, 2, 3]]), ZZ, 1) assert f.num == [[1, 2], [3]] assert f.den == [[1, 2, 3]] assert f.lev == 1 assert f.dom == ZZ f = DMF(([[-1], [-2]], [[3], [-4]]), ZZ) assert f.num == [[-1], [-2]] assert f.den == [[3], [-4]] assert f.lev == 1 assert f.dom == ZZ f = DMF(([[1], [2]], [[-3], [4]]), ZZ) assert f.num == [[-1], [-2]] assert f.den == [[3], [-4]] assert f.lev == 1 assert f.dom == ZZ f = DMF(([[1], [2]], [[-3], [4]]), ZZ) assert f.num == [[-1], [-2]] assert f.den == [[3], [-4]] assert f.lev == 1 assert f.dom == ZZ f = DMF(([[]], [[-3], [4]]), ZZ) assert f.num == [[]] assert f.den == [[1]] assert f.lev == 1 assert f.dom == ZZ f = DMF(17, ZZ, 1) assert f.num == [[17]] assert f.den == [[1]] assert f.lev == 1 assert f.dom == ZZ f = DMF(([[1], [2]]), ZZ) assert f.num == [[1], [2]] assert f.den == [[1]] assert f.lev == 1 assert f.dom == ZZ f = DMF([[0], [], [0, 1, 2], [3]], ZZ) assert f.num == [[1, 2], [3]] assert f.den == [[1]] assert f.lev == 1 assert f.dom == ZZ f = DMF({(1, 1): 1, (0, 0): 2}, ZZ, 1) assert f.num == [[1, 0], [2]] assert f.den == [[1]] assert f.lev == 1 assert f.dom == ZZ f = DMF(([[QQ(1)], [QQ(2)]], [[-QQ(3)], [QQ(4)]]), QQ) assert f.num == [[-QQ(1)], [-QQ(2)]] assert f.den == [[QQ(3)], [-QQ(4)]] assert f.lev == 1 assert f.dom == QQ f = DMF(([[QQ(1, 5)], [QQ(2, 5)]], [[-QQ(3, 7)], [QQ(4, 7)]]), QQ) assert f.num == [[-QQ(7)], [-QQ(14)]] assert f.den == [[QQ(15)], [-QQ(20)]] assert f.lev == 1 assert f.dom == QQ raises(ValueError, lambda: DMF(([1], [[1]]), ZZ)) raises(ZeroDivisionError, lambda: DMF(([1], []), ZZ)) def test_DMF__bool__(): assert bool(DMF([[]], ZZ)) is False assert bool(DMF([[1]], ZZ)) is True def test_DMF_properties(): assert DMF([[]], ZZ).is_zero is True assert DMF([[]], ZZ).is_one is False assert DMF([[1]], ZZ).is_zero is False assert DMF([[1]], ZZ).is_one is True assert DMF(([[1]], [[2]]), ZZ).is_one is False def test_DMF_arithmetics(): f = DMF([[7], [-9]], ZZ) g = DMF([[-7], [9]], ZZ) assert f.neg() == -f == g f = DMF(([[1]], [[1], []]), ZZ) g = DMF(([[1]], [[1, 0]]), ZZ) h = DMF(([[1], [1, 0]], [[1, 0], []]), ZZ) assert f.add(g) == f + g == h assert g.add(f) == g + f == h h = DMF(([[-1], [1, 0]], [[1, 0], []]), ZZ) assert f.sub(g) == f - g == h h = DMF(([[1]], [[1, 0], []]), ZZ) assert f.mul(g) == f*g == h assert g.mul(f) == g*f == h h = DMF(([[1, 0]], [[1], []]), ZZ) assert f.quo(g) == f/g == h h = DMF(([[1]], [[1], [], [], []]), ZZ) assert f.pow(3) == f**3 == h h = DMF(([[1]], [[1, 0, 0, 0]]), ZZ) assert g.pow(3) == g**3 == h h = DMF(([[1, 0]], [[1]]), ZZ) assert g.pow(-1) == g**-1 == h def test_ANP___init__(): rep = [QQ(1), QQ(1)] mod = [QQ(1), QQ(0), QQ(1)] f = ANP(rep, mod, QQ) assert f.rep == [QQ(1), QQ(1)] assert f.mod == [QQ(1), QQ(0), QQ(1)] assert f.dom == QQ rep = {1: QQ(1), 0: QQ(1)} mod = {2: QQ(1), 0: QQ(1)} f = ANP(rep, mod, QQ) assert f.rep == [QQ(1), QQ(1)] assert f.mod == [QQ(1), QQ(0), QQ(1)] assert f.dom == QQ f = ANP(1, mod, QQ) assert f.rep == [QQ(1)] assert f.mod == [QQ(1), QQ(0), QQ(1)] assert f.dom == QQ def test_ANP___eq__(): a = ANP([QQ(1), QQ(1)], [QQ(1), QQ(0), QQ(1)], QQ) b = ANP([QQ(1), QQ(1)], [QQ(1), QQ(0), QQ(2)], QQ) assert (a == a) is True assert (a != a) is False assert (a == b) is False assert (a != b) is True b = ANP([QQ(1), QQ(2)], [QQ(1), QQ(0), QQ(1)], QQ) assert (a == b) is False assert (a != b) is True def test_ANP___bool__(): assert bool(ANP([], [QQ(1), QQ(0), QQ(1)], QQ)) is False assert bool(ANP([QQ(1)], [QQ(1), QQ(0), QQ(1)], QQ)) is True def test_ANP_properties(): mod = [QQ(1), QQ(0), QQ(1)] assert ANP([QQ(0)], mod, QQ).is_zero is True assert ANP([QQ(1)], mod, QQ).is_zero is False assert ANP([QQ(1)], mod, QQ).is_one is True assert ANP([QQ(2)], mod, QQ).is_one is False def test_ANP_arithmetics(): mod = [QQ(1), QQ(0), QQ(0), QQ(-2)] a = ANP([QQ(2), QQ(-1), QQ(1)], mod, QQ) b = ANP([QQ(1), QQ(2)], mod, QQ) c = ANP([QQ(-2), QQ(1), QQ(-1)], mod, QQ) assert a.neg() == -a == c c = ANP([QQ(2), QQ(0), QQ(3)], mod, QQ) assert a.add(b) == a + b == c assert b.add(a) == b + a == c c = ANP([QQ(2), QQ(-2), QQ(-1)], mod, QQ) assert a.sub(b) == a - b == c c = ANP([QQ(-2), QQ(2), QQ(1)], mod, QQ) assert b.sub(a) == b - a == c c = ANP([QQ(3), QQ(-1), QQ(6)], mod, QQ) assert a.mul(b) == a*b == c assert b.mul(a) == b*a == c c = ANP([QQ(-1, 43), QQ(9, 43), QQ(5, 43)], mod, QQ) assert a.pow(0) == a**(0) == ANP(1, mod, QQ) assert a.pow(1) == a**(1) == a assert a.pow(-1) == a**(-1) == c assert a.quo(a) == a.mul(a.pow(-1)) == a*a**(-1) == ANP(1, mod, QQ) c = ANP([], [1, 0, 0, -2], QQ) r1 = a.rem(b) (q, r2) = a.div(b) assert r1 == r2 == c == a % b raises(NotInvertible, lambda: a.div(c)) raises(NotInvertible, lambda: a.rem(c)) # Comparison with "hard-coded" value fails despite looking identical # from sympy import Rational # c = ANP([Rational(11, 10), Rational(-1, 5), Rational(-3, 5)], [1, 0, 0, -2], QQ) assert q == a/b # == c def test_ANP_unify(): mod = [QQ(1), QQ(0), QQ(-2)] a = ANP([QQ(1)], mod, QQ) b = ANP([ZZ(1)], mod, ZZ) assert a.unify(b)[0] == QQ assert b.unify(a)[0] == QQ assert a.unify(a)[0] == QQ assert b.unify(b)[0] == ZZ def test___hash__(): # issue 5571 # Make sure int vs. long doesn't affect hashing with Python ground types assert DMP([[1, 2], [3]], ZZ) == DMP([[int(1), int(2)], [int(3)]], ZZ) assert hash(DMP([[1, 2], [3]], ZZ)) == hash(DMP([[int(1), int(2)], [int(3)]], ZZ)) assert DMF( ([[1, 2], [3]], [[1]]), ZZ) == DMF(([[int(1), int(2)], [int(3)]], [[int(1)]]), ZZ) assert hash(DMF(([[1, 2], [3]], [[1]]), ZZ)) == hash(DMF(([[int(1), int(2)], [int(3)]], [[int(1)]]), ZZ)) assert ANP([1, 1], [1, 0, 1], ZZ) == ANP([int(1), int(1)], [int(1), int(0), int(1)], ZZ) assert hash( ANP([1, 1], [1, 0, 1], ZZ)) == hash(ANP([int(1), int(1)], [int(1), int(0), int(1)], ZZ))
c9d3bff9449d415a4be37beca34b73367f19d6f54943fb1ec3b94fb0b377d811
from sympy.testing.pytest import raises from sympy.polys.polymatrix import PolyMatrix from sympy.polys import Poly from sympy import S, QQ, ZZ, Matrix from sympy.abc import x, y def _test_polymatrix(): pm1 = PolyMatrix([[Poly(x**2, x), Poly(-x, x)], [Poly(x**3, x), Poly(-1 + x, x)]]) v1 = PolyMatrix([[1, 0], [-1, 0]], ring='ZZ[x]') m1 = PolyMatrix([[1, 0], [-1, 0]], ring='ZZ[x]') A = PolyMatrix([[Poly(x**2 + x, x), Poly(0, x)], \ [Poly(x**3 - x + 1, x), Poly(0, x)]]) B = PolyMatrix([[Poly(x**2, x), Poly(-x, x)], [Poly(-x**2, x), Poly(x, x)]]) assert A.ring == ZZ[x] assert isinstance(pm1*v1, PolyMatrix) assert pm1*v1 == A assert pm1*m1 == A assert v1*pm1 == B pm2 = PolyMatrix([[Poly(x**2, x, domain='QQ'), Poly(0, x, domain='QQ'), Poly(-x**2, x, domain='QQ'), \ Poly(x**3, x, domain='QQ'), Poly(0, x, domain='QQ'), Poly(-x**3, x, domain='QQ')]]) assert pm2.ring == QQ[x] v2 = PolyMatrix([1, 0, 0, 0, 0, 0], ring='ZZ[x]') m2 = PolyMatrix([1, 0, 0, 0, 0, 0], ring='ZZ[x]') C = PolyMatrix([[Poly(x**2, x, domain='QQ')]]) assert pm2*v2 == C assert pm2*m2 == C pm3 = PolyMatrix([[Poly(x**2, x), S.One]], ring='ZZ[x]') v3 = S.Half*pm3 assert v3 == PolyMatrix([[Poly(S.Half*x**2, x, domain='QQ'), S.Half]], ring='QQ[x]') assert pm3*S.Half == v3 assert v3.ring == QQ[x] pm4 = PolyMatrix([[Poly(x**2, x, domain='ZZ'), Poly(-x**2, x, domain='ZZ')]]) v4 = PolyMatrix([1, -1], ring='ZZ[x]') assert pm4*v4 == PolyMatrix([[Poly(2*x**2, x, domain='ZZ')]]) assert len(PolyMatrix(ring=ZZ[x])) == 0 assert PolyMatrix([1, 0, 0, 1], x)/(-1) == PolyMatrix([-1, 0, 0, -1], x) def test_polymatrix_constructor(): M1 = PolyMatrix([[x, y]], ring=QQ[x,y]) assert M1.ring == QQ[x,y] assert M1.domain == QQ assert M1.gens == (x, y) assert M1.shape == (1, 2) assert M1.rows == 1 assert M1.cols == 2 assert len(M1) == 2 assert list(M1) == [Poly(x, (x, y), domain=QQ), Poly(y, (x, y), domain=QQ)] M2 = PolyMatrix([[x, y]], ring=QQ[x][y]) assert M2.ring == QQ[x][y] assert M2.domain == QQ[x] assert M2.gens == (y,) assert M2.shape == (1, 2) assert M2.rows == 1 assert M2.cols == 2 assert len(M2) == 2 assert list(M2) == [Poly(x, (y,), domain=QQ[x]), Poly(y, (y,), domain=QQ[x])] assert PolyMatrix([[x, y]], y) == PolyMatrix([[x, y]], ring=ZZ.frac_field(x)[y]) assert PolyMatrix([[x, y]], ring='ZZ[x,y]') == PolyMatrix([[x, y]], ring=ZZ[x,y]) assert PolyMatrix([[x, y]], (x, y)) == PolyMatrix([[x, y]], ring=QQ[x,y]) assert PolyMatrix([[x, y]], x, y) == PolyMatrix([[x, y]], ring=QQ[x,y]) assert PolyMatrix([x, y]) == PolyMatrix([[x], [y]], ring=QQ[x,y]) assert PolyMatrix(1, 2, [x, y]) == PolyMatrix([[x, y]], ring=QQ[x,y]) assert PolyMatrix(1, 2, lambda i,j: [x,y][j]) == PolyMatrix([[x, y]], ring=QQ[x,y]) assert PolyMatrix(0, 2, [], x, y).shape == (0, 2) assert PolyMatrix(2, 0, [], x, y).shape == (2, 0) assert PolyMatrix([[], []], x, y).shape == (2, 0) assert PolyMatrix(ring=QQ[x,y]) == PolyMatrix(0, 0, [], ring=QQ[x,y]) == PolyMatrix([], ring=QQ[x,y]) raises(TypeError, lambda: PolyMatrix()) raises(TypeError, lambda: PolyMatrix(1)) assert PolyMatrix([Poly(x), Poly(y)]) == PolyMatrix([[x], [y]], ring=ZZ[x,y]) # XXX: Maybe a bug in parallel_poly_from_expr (x lost from gens and domain): assert PolyMatrix([Poly(y, x), 1]) == PolyMatrix([[y], [1]], ring=QQ[y]) def test_polymatrix_eq(): assert (PolyMatrix([x]) == PolyMatrix([x])) is True assert (PolyMatrix([y]) == PolyMatrix([x])) is False assert (PolyMatrix([x]) != PolyMatrix([x])) is False assert (PolyMatrix([y]) != PolyMatrix([x])) is True assert PolyMatrix([[x, y]]) != PolyMatrix([x, y]) == PolyMatrix([[x], [y]]) assert PolyMatrix([x], ring=QQ[x]) != PolyMatrix([x], ring=ZZ[x]) assert PolyMatrix([x]) != Matrix([x]) assert PolyMatrix([x]).to_Matrix() == Matrix([x]) assert PolyMatrix([1], x) == PolyMatrix([1], x) assert PolyMatrix([1], x) != PolyMatrix([1], y) def test_polymatrix_from_Matrix(): assert PolyMatrix.from_Matrix(Matrix([1, 2]), x) == PolyMatrix([1, 2], x, ring=QQ[x]) assert PolyMatrix.from_Matrix(Matrix([1]), ring=QQ[x]) == PolyMatrix([1], x) pmx = PolyMatrix([1, 2], x) pmy = PolyMatrix([1, 2], y) assert pmx != pmy assert pmx.set_gens(y) == pmy def test_polymatrix_repr(): assert repr(PolyMatrix([[1, 2]], x)) == 'PolyMatrix([[1, 2]], ring=QQ[x])' assert repr(PolyMatrix(0, 2, [], x)) == 'PolyMatrix(0, 2, [], ring=QQ[x])' def test_polymatrix_getitem(): M = PolyMatrix([[1, 2], [3, 4]], x) assert M[:, :] == M assert M[0, :] == PolyMatrix([[1, 2]], x) assert M[:, 0] == PolyMatrix([1, 3], x) assert M[0, 0] == Poly(1, x, domain=QQ) assert M[0] == Poly(1, x, domain=QQ) assert M[:2] == [Poly(1, x, domain=QQ), Poly(2, x, domain=QQ)] def test_polymatrix_arithmetic(): M = PolyMatrix([[1, 2], [3, 4]], x) assert M + M == PolyMatrix([[2, 4], [6, 8]], x) assert M - M == PolyMatrix([[0, 0], [0, 0]], x) assert -M == PolyMatrix([[-1, -2], [-3, -4]], x) raises(TypeError, lambda: M + 1) raises(TypeError, lambda: M - 1) raises(TypeError, lambda: 1 + M) raises(TypeError, lambda: 1 - M) assert M * M == PolyMatrix([[7, 10], [15, 22]], x) assert 2 * M == PolyMatrix([[2, 4], [6, 8]], x) assert M * 2 == PolyMatrix([[2, 4], [6, 8]], x) assert S(2) * M == PolyMatrix([[2, 4], [6, 8]], x) assert M * S(2) == PolyMatrix([[2, 4], [6, 8]], x) raises(TypeError, lambda: [] * M) raises(TypeError, lambda: M * []) M2 = PolyMatrix([[1, 2]], ring=ZZ[x]) assert S.Half * M2 == PolyMatrix([[S.Half, 1]], ring=QQ[x]) assert M2 * S.Half == PolyMatrix([[S.Half, 1]], ring=QQ[x]) assert M / 2 == PolyMatrix([[S(1)/2, 1], [S(3)/2, 2]], x) assert M / Poly(2, x) == PolyMatrix([[S(1)/2, 1], [S(3)/2, 2]], x) raises(TypeError, lambda: M / []) def test_polymatrix_manipulations(): M1 = PolyMatrix([[1, 2], [3, 4]], x) assert M1.transpose() == PolyMatrix([[1, 3], [2, 4]], x) M2 = PolyMatrix([[5, 6], [7, 8]], x) assert M1.row_join(M2) == PolyMatrix([[1, 2, 5, 6], [3, 4, 7, 8]], x) assert M1.col_join(M2) == PolyMatrix([[1, 2], [3, 4], [5, 6], [7, 8]], x) assert M1.applyfunc(lambda e: 2*e) == PolyMatrix([[2, 4], [6, 8]], x) def test_polymatrix_ones_zeros(): assert PolyMatrix.zeros(1, 2, x) == PolyMatrix([[0, 0]], x) assert PolyMatrix.eye(2, x) == PolyMatrix([[1, 0], [0, 1]], x) def test_polymatrix_rref(): M = PolyMatrix([[1, 2], [3, 4]], x) assert M.rref() == (PolyMatrix.eye(2, x), (0, 1)) raises(ValueError, lambda: PolyMatrix([1, 2], ring=ZZ[x]).rref()) raises(ValueError, lambda: PolyMatrix([1, x], ring=QQ[x]).rref()) def test_polymatrix_nullspace(): M = PolyMatrix([[1, 2], [3, 6]], x) assert M.nullspace() == [PolyMatrix([-2, 1], x)] raises(ValueError, lambda: PolyMatrix([1, 2], ring=ZZ[x]).nullspace()) raises(ValueError, lambda: PolyMatrix([1, x], ring=QQ[x]).nullspace()) assert M.rank() == 1
ced39e98ede4b0ddaa8e2d17e54aa64e96151ca32f02c117d4c7c2a8df889dbd
'''Functions returning normal forms of matrices''' from .domainmatrix import DomainMatrix def smith_normal_form(m): ''' Return the Smith Normal Form of a matrix `m` over the ring `domain`. This will only work if the ring is a principal ideal domain. Examples ======== >>> from sympy import ZZ >>> from sympy.polys.matrices import DomainMatrix >>> from sympy.polys.matrices.normalforms import smith_normal_form >>> m = DomainMatrix([[ZZ(12), ZZ(6), ZZ(4)], ... [ZZ(3), ZZ(9), ZZ(6)], ... [ZZ(2), ZZ(16), ZZ(14)]], (3, 3), ZZ) >>> print(smith_normal_form(m).to_Matrix()) Matrix([[1, 0, 0], [0, 10, 0], [0, 0, -30]]) ''' invs = invariant_factors(m) smf = DomainMatrix.diag(invs, m.domain, m.shape) return smf def invariant_factors(m): ''' Return the tuple of abelian invariants for a matrix `m` (as in the Smith-Normal form) References ========== [1] https://en.wikipedia.org/wiki/Smith_normal_form#Algorithm [2] http://sierra.nmsu.edu/morandi/notes/SmithNormalForm.pdf ''' domain = m.domain if not domain.is_PID: msg = "The matrix entries must be over a principal ideal domain" raise ValueError(msg) if 0 in m.shape: return () rows, cols = shape = m.shape m = list(m.to_dense().rep) def add_rows(m, i, j, a, b, c, d): # replace m[i, :] by a*m[i, :] + b*m[j, :] # and m[j, :] by c*m[i, :] + d*m[j, :] for k in range(cols): e = m[i][k] m[i][k] = a*e + b*m[j][k] m[j][k] = c*e + d*m[j][k] def add_columns(m, i, j, a, b, c, d): # replace m[:, i] by a*m[:, i] + b*m[:, j] # and m[:, j] by c*m[:, i] + d*m[:, j] for k in range(rows): e = m[k][i] m[k][i] = a*e + b*m[k][j] m[k][j] = c*e + d*m[k][j] def clear_column(m): # make m[1:, 0] zero by row and column operations if m[0][0] == 0: return m # pragma: nocover pivot = m[0][0] for j in range(1, rows): if m[j][0] == 0: continue d, r = domain.div(m[j][0], pivot) if r == 0: add_rows(m, 0, j, 1, 0, -d, 1) else: a, b, g = domain.gcdex(pivot, m[j][0]) d_0 = domain.div(m[j][0], g)[0] d_j = domain.div(pivot, g)[0] add_rows(m, 0, j, a, b, d_0, -d_j) pivot = g return m def clear_row(m): # make m[0, 1:] zero by row and column operations if m[0][0] == 0: return m # pragma: nocover pivot = m[0][0] for j in range(1, cols): if m[0][j] == 0: continue d, r = domain.div(m[0][j], pivot) if r == 0: add_columns(m, 0, j, 1, 0, -d, 1) else: a, b, g = domain.gcdex(pivot, m[0][j]) d_0 = domain.div(m[0][j], g)[0] d_j = domain.div(pivot, g)[0] add_columns(m, 0, j, a, b, d_0, -d_j) pivot = g return m # permute the rows and columns until m[0,0] is non-zero if possible ind = [i for i in range(rows) if m[i][0] != 0] if ind and ind[0] != 0: m[0], m[ind[0]] = m[ind[0]], m[0] else: ind = [j for j in range(cols) if m[0][j] != 0] if ind and ind[0] != 0: for row in m: row[0], row[ind[0]] = row[ind[0]], row[0] # make the first row and column except m[0,0] zero while (any([m[0][i] != 0 for i in range(1,cols)]) or any([m[i][0] != 0 for i in range(1,rows)])): m = clear_column(m) m = clear_row(m) if 1 in shape: invs = () else: lower_right = DomainMatrix([r[1:] for r in m[1:]], (rows-1, cols-1), domain) invs = invariant_factors(lower_right) if m[0][0]: result = [m[0][0]] result.extend(invs) # in case m[0] doesn't divide the invariants of the rest of the matrix for i in range(len(result)-1): if result[i] and domain.div(result[i+1], result[i])[1] != 0: g = domain.gcd(result[i+1], result[i]) result[i+1] = domain.div(result[i], g)[0]*result[i+1] result[i] = g else: break else: result = invs + (m[0][0],) return tuple(result)
4bc01c3dc9645628a0a2344965e10e11c4c44d82efe9f2cccbe3ac9132afdecb
""" Module for the DomainMatrix class. A DomainMatrix represents a matrix with elements that are in a particular Domain. Each DomainMatrix internally wraps a DDM which is used for the lower-level operations. The idea is that the DomainMatrix class provides the convenience routines for converting between Expr and the poly domains as well as unifying matrices with different domains. """ from sympy.core.sympify import _sympify from ..constructor import construct_domain from .exceptions import (NonSquareMatrixError, ShapeError, DDMShapeError, DDMDomainError, DDMFormatError, DDMBadInputError) from .ddm import DDM from .sdm import SDM from .domainscalar import DomainScalar from sympy.polys.domains import ZZ class DomainMatrix: r""" Associate Matrix with :py:class:`~.Domain` Explanation =========== DomainMatrix uses :py:class:`~.Domain` for its internal representation which makes it more faster for many common operations than current sympy Matrix class, but this advantage makes it not entirely compatible with Matrix. DomainMatrix could be found analogous to numpy arrays with "dtype". In the DomainMatrix, each matrix has a domain such as :ref:`ZZ` or :ref:`QQ(a)`. Examples ======== Creating a DomainMatrix from the existing Matrix class: >>> from sympy import Matrix >>> from sympy.polys.matrices import DomainMatrix >>> Matrix1 = Matrix([ ... [1, 2], ... [3, 4]]) >>> A = DomainMatrix.from_Matrix(Matrix1) >>> A DomainMatrix({0: {0: 1, 1: 2}, 1: {0: 3, 1: 4}}, (2, 2), ZZ) Driectly forming a DomainMatrix: >>> from sympy import ZZ >>> from sympy.polys.matrices import DomainMatrix >>> A = DomainMatrix([ ... [ZZ(1), ZZ(2)], ... [ZZ(3), ZZ(4)]], (2, 2), ZZ) >>> A DomainMatrix([[1, 2], [3, 4]], (2, 2), ZZ) See Also ======== DDM SDM Domain Poly """ def __new__(cls, rows, shape, domain, *, fmt=None): """ Creates a :py:class:`~.DomainMatrix`. Parameters ========== rows : Represents elements of DomainMatrix as list of lists shape : Represents dimension of DomainMatrix domain : Represents :py:class:`~.Domain` of DomainMatrix Raises ====== TypeError If any of rows, shape and domain are not provided """ if isinstance(rows, (DDM, SDM)): raise TypeError("Use from_rep to initialise from SDM/DDM") elif isinstance(rows, list): rep = DDM(rows, shape, domain) elif isinstance(rows, dict): rep = SDM(rows, shape, domain) else: msg = "Input should be list-of-lists or dict-of-dicts" raise TypeError(msg) if fmt is not None: if fmt == 'sparse': rep = rep.to_sdm() elif fmt == 'dense': rep = rep.to_ddm() else: raise ValueError("fmt should be 'sparse' or 'dense'") return cls.from_rep(rep) def __getitem__(self, key): i, j = key m, n = self.shape if not (isinstance(i, slice) or isinstance(j, slice)): return DomainScalar(self.rep.getitem(i, j), self.domain) if not isinstance(i, slice): if not -m <= i < m: raise IndexError("Row index out of range") i = i % m i = slice(i, i+1) if not isinstance(j, slice): if not -n <= j < n: raise IndexError("Column index out of range") j = j % n j = slice(j, j+1) return self.from_rep(self.rep.extract_slice(i, j)) @classmethod def from_rep(cls, rep): """Create a new DomainMatrix efficiently from DDM/SDM. Examples ======== Create a :py:class:`~.DomainMatrix` with an dense internal representation as :py:class:`~.DDM`: >>> from sympy.polys.domains import ZZ >>> from sympy.polys.matrices import DomainMatrix >>> from sympy.polys.matrices.ddm import DDM >>> drep = DDM([[ZZ(1), ZZ(2)], [ZZ(3), ZZ(4)]], (2, 2), ZZ) >>> dM = DomainMatrix.from_rep(drep) >>> dM DomainMatrix([[1, 2], [3, 4]], (2, 2), ZZ) Create a :py:class:`~.DomainMatrix` with a sparse internal representation as :py:class:`~.SDM`: >>> from sympy.polys.matrices import DomainMatrix >>> from sympy.polys.matrices.sdm import SDM >>> from sympy import ZZ >>> drep = SDM({0:{1:ZZ(1)},1:{0:ZZ(2)}}, (2, 2), ZZ) >>> dM = DomainMatrix.from_rep(drep) >>> dM DomainMatrix({0: {1: 1}, 1: {0: 2}}, (2, 2), ZZ) Parameters ========== rep: SDM or DDM The internal sparse or dense representation of the matrix. Returns ======= DomainMatrix A :py:class:`~.DomainMatrix` wrapping *rep*. Notes ===== This takes ownership of rep as its internal representation. If rep is being mutated elsewhere then a copy should be provided to ``from_rep``. Only minimal verification or checking is done on *rep* as this is supposed to be an efficient internal routine. """ if not isinstance(rep, (DDM, SDM)): raise TypeError("rep should be of type DDM or SDM") self = super().__new__(cls) self.rep = rep self.shape = rep.shape self.domain = rep.domain return self @classmethod def from_list_sympy(cls, nrows, ncols, rows, **kwargs): r""" Convert a list of lists of Expr into a DomainMatrix using construct_domain Parameters ========== nrows: number of rows ncols: number of columns rows: list of lists Returns ======= DomainMatrix containing elements of rows Examples ======== >>> from sympy.polys.matrices import DomainMatrix >>> from sympy.abc import x, y, z >>> A = DomainMatrix.from_list_sympy(1, 3, [[x, y, z]]) >>> A DomainMatrix([[x, y, z]], (1, 3), ZZ[x,y,z]) See Also ======== sympy.polys.constructor.construct_domain, from_dict_sympy """ assert len(rows) == nrows assert all(len(row) == ncols for row in rows) items_sympy = [_sympify(item) for row in rows for item in row] domain, items_domain = cls.get_domain(items_sympy, **kwargs) domain_rows = [[items_domain[ncols*r + c] for c in range(ncols)] for r in range(nrows)] return DomainMatrix(domain_rows, (nrows, ncols), domain) @classmethod def from_dict_sympy(cls, nrows, ncols, elemsdict, **kwargs): """ Parameters ========== nrows: number of rows ncols: number of cols elemsdict: dict of dicts containing non-zero elements of the DomainMatrix Returns ======= DomainMatrix containing elements of elemsdict Examples ======== >>> from sympy.polys.matrices import DomainMatrix >>> from sympy.abc import x,y,z >>> elemsdict = {0: {0:x}, 1:{1: y}, 2: {2: z}} >>> A = DomainMatrix.from_dict_sympy(3, 3, elemsdict) >>> A DomainMatrix({0: {0: x}, 1: {1: y}, 2: {2: z}}, (3, 3), ZZ[x,y,z]) See Also ======== from_list_sympy """ if not all(0 <= r < nrows for r in elemsdict): raise DDMBadInputError("Row out of range") if not all(0 <= c < ncols for row in elemsdict.values() for c in row): raise DDMBadInputError("Column out of range") items_sympy = [_sympify(item) for row in elemsdict.values() for item in row.values()] domain, items_domain = cls.get_domain(items_sympy, **kwargs) idx = 0 items_dict = {} for i, row in elemsdict.items(): items_dict[i] = {} for j in row: items_dict[i][j] = items_domain[idx] idx += 1 return DomainMatrix(items_dict, (nrows, ncols), domain) @classmethod def from_Matrix(cls, M, fmt='sparse',**kwargs): r""" Convert Matrix to DomainMatrix Parameters ========== M: Matrix Returns ======= Returns DomainMatrix with identical elements as M Examples ======== >>> from sympy import Matrix >>> from sympy.polys.matrices import DomainMatrix >>> M = Matrix([ ... [1.0, 3.4], ... [2.4, 1]]) >>> A = DomainMatrix.from_Matrix(M) >>> A DomainMatrix({0: {0: 1.0, 1: 3.4}, 1: {0: 2.4, 1: 1.0}}, (2, 2), RR) We can keep internal representation as ddm using fmt='dense' >>> from sympy import Matrix, QQ >>> from sympy.polys.matrices import DomainMatrix >>> A = DomainMatrix.from_Matrix(Matrix([[QQ(1, 2), QQ(3, 4)], [QQ(0, 1), QQ(0, 1)]]), fmt='dense') >>> A.rep [[1/2, 3/4], [0, 0]] See Also ======== Matrix """ if fmt == 'dense': return cls.from_list_sympy(*M.shape, M.tolist(), **kwargs) return cls.from_dict_sympy(*M.shape, M.todod(), **kwargs) @classmethod def get_domain(cls, items_sympy, **kwargs): K, items_K = construct_domain(items_sympy, **kwargs) return K, items_K def convert_to(self, K): r""" Change the domain of DomainMatrix to desired domain or field Parameters ========== K : Represents the desired domain or field Returns ======= DomainMatrix DomainMatrix with the desired domain or field Examples ======== >>> from sympy import ZZ, ZZ_I >>> from sympy.polys.matrices import DomainMatrix >>> A = DomainMatrix([ ... [ZZ(1), ZZ(2)], ... [ZZ(3), ZZ(4)]], (2, 2), ZZ) >>> A.convert_to(ZZ_I) DomainMatrix([[1, 2], [3, 4]], (2, 2), ZZ_I) """ return self.from_rep(self.rep.convert_to(K)) def to_field(self): r""" Returns a DomainMatrix with the appropriate field Returns ======= DomainMatrix DomainMatrix with the appropriate field Examples ======== >>> from sympy import ZZ >>> from sympy.polys.matrices import DomainMatrix >>> A = DomainMatrix([ ... [ZZ(1), ZZ(2)], ... [ZZ(3), ZZ(4)]], (2, 2), ZZ) >>> A.to_field() DomainMatrix([[1, 2], [3, 4]], (2, 2), QQ) """ K = self.domain.get_field() return self.convert_to(K) def to_sparse(self): """ Return a sparse DomainMatrix representation of *self*. Examples ======== >>> from sympy.polys.matrices import DomainMatrix >>> from sympy import QQ >>> A = DomainMatrix([[1, 0],[0, 2]], (2, 2), QQ) >>> A.rep [[1, 0], [0, 2]] >>> B = A.to_sparse() >>> B.rep {0: {0: 1}, 1: {1: 2}} """ if self.rep.fmt == 'sparse': return self return self.from_rep(SDM.from_ddm(self.rep)) def to_dense(self): """ Return a dense DomainMatrix representation of *self*. Examples ======== >>> from sympy.polys.matrices import DomainMatrix >>> from sympy import QQ >>> A = DomainMatrix({0: {0: 1}, 1: {1: 2}}, (2, 2), QQ) >>> A.rep {0: {0: 1}, 1: {1: 2}} >>> B = A.to_dense() >>> B.rep [[1, 0], [0, 2]] """ if self.rep.fmt == 'dense': return self return self.from_rep(SDM.to_ddm(self.rep)) def _unify_domain(self, other): """Convert self and other to a common domain""" K1 = self.domain K2 = other.domain if K1 == K2: return self, other K = K1.unify(K2) if K1 != K: self = self.convert_to(K) if K2 != K: other = other.convert_to(K) return self, other def _unify_fmt(self, other, fmt): """Convert self and other to the same format. If both are sparse or both are dense then return both unmodified. Otherwise convert both to the preferred format given as *fmt* which should be 'dense' or 'sparse'. """ if self.rep.fmt == other.rep.fmt: return self, other elif fmt == 'sparse': return self.to_sparse(), other.to_sparse() elif fmt == 'dense': return self.to_dense(), other.to_dense() else: raise ValueError("fmt should be 'sparse' or 'dense'") def unify(self, other, *, fmt=None): """ Unifies the domains and the format of self and other matrices. Parameters ========== other : another DomainMatrix fmt: string 'dense', 'sparse' or `None` (default) The preferred format to convert to if self and other are not already in the same format. If `None` or not specified then no conversion if performed. Returns ======= (dM1, dM2) dM1, dM2 DomainMatrix matrices with unified Domain and format Examples ======== Unify the domain of DomainMatrix that have different domains: >>> from sympy import ZZ, QQ >>> from sympy.polys.matrices import DomainMatrix >>> A = DomainMatrix([[ZZ(1), ZZ(2)]], (1, 2), ZZ) >>> B = DomainMatrix([[QQ(1, 2), QQ(2)]], (1, 2), QQ) >>> Aq, Bq = A.unify(B) >>> Aq DomainMatrix([[1, 2]], (1, 2), QQ) >>> Bq DomainMatrix([[1/2, 2]], (1, 2), QQ) Unify the format (dense or sparse): >>> A = DomainMatrix([[ZZ(1), ZZ(2)]], (1, 2), ZZ) >>> B = DomainMatrix({0:{0: ZZ(1)}}, (2, 2), ZZ) >>> B.rep {0: {0: 1}} >>> A2, B2 = A.unify(B, fmt='dense') >>> B2.rep [[1, 0], [0, 0]] See Also ======== convert_to, to_dense, to_sparse """ dM1, dM2 = self._unify_domain(other) if fmt is not None: dM1, dM2 = dM1._unify_fmt(dM2, fmt) return dM1, dM2 def to_Matrix(self): r""" Convert DomainMatrix to Matrix Returns ======= Matrix MutableDenseMatrix for the DomainMatrix Examples ======== >>> from sympy import ZZ >>> from sympy.polys.matrices import DomainMatrix >>> A = DomainMatrix([ ... [ZZ(1), ZZ(2)], ... [ZZ(3), ZZ(4)]], (2, 2), ZZ) >>> A.to_Matrix() Matrix([ [1, 2], [3, 4]]) See Also ======== from_Matrix """ from sympy.matrices.dense import MutableDenseMatrix elemlist = self.rep.to_list() elements_sympy = [self.domain.to_sympy(e) for row in elemlist for e in row] return MutableDenseMatrix(*self.shape, elements_sympy) def __repr__(self): return 'DomainMatrix(%s, %r, %r)' % (str(self.rep), self.shape, self.domain) def transpose(self): """Matrix transpose of ``self``""" return self.from_rep(self.rep.transpose()) def flat(self): rows, cols = self.shape return [self[i,j].element for i in range(rows) for j in range(cols)] @property def is_zero_matrix(self): return all(self[i, j].element == self.domain.zero for i in range(self.shape[0]) for j in range(self.shape[1])) def hstack(A, B): r""" Horizontally stacks 2 Domain Matrices. Parameters ========== A, B: DomainMatrix to stack the rows horizontally Returns ======= DomainMatrix DomainMatrix by stacking the rows horizontally Examples ======== >>> from sympy import ZZ, QQ >>> from sympy.polys.matrices import DomainMatrix >>> A = DomainMatrix([[ZZ(1), ZZ(2), ZZ(3)]], (1, 3), ZZ) >>> B = DomainMatrix([[QQ(-1, 2), QQ(1, 2), QQ(1, 3)]],(1, 3), QQ) >>> A.hstack(B) DomainMatrix([[1, 2, 3, -1/2, 1/2, 1/3]], (1, 6), QQ) See Also ======== unify """ A, B = A.unify(B, fmt='dense') return A.from_rep(A.rep.hstack(B.rep)) def vstack(A, B): A, B = A.unify(B, fmt='dense') return A.from_rep(A.rep.vstack(B.rep)) def applyfunc(self, func, domain=None): if domain is None: domain = self.domain return self.from_rep(self.rep.applyfunc(func, domain)) def __add__(A, B): if not isinstance(B, DomainMatrix): return NotImplemented A, B = A.unify(B, fmt='dense') return A.add(B) def __sub__(A, B): if not isinstance(B, DomainMatrix): return NotImplemented A, B = A.unify(B, fmt='dense') return A.sub(B) def __neg__(A): return A.neg() def __mul__(A, B): """A * B""" if isinstance(B, DomainMatrix): A, B = A.unify(B, fmt='dense') return A.matmul(B) elif B in A.domain: return A.from_rep(A.rep * B) elif isinstance(B, DomainScalar): A, B = A.unify(B) return A.scalarmul(B) else: return NotImplemented def __rmul__(A, B): if B in A.domain: return A.from_rep(A.rep * B) elif isinstance(B, DomainScalar): A, B = A.unify(B) return A.scalarmul(B) else: return NotImplemented def __pow__(A, n): """A ** n""" if not isinstance(n, int): return NotImplemented return A.pow(n) def _check(a, op, b, ashape, bshape): if a.domain != b.domain: msg = "Domain mismatch: %s %s %s" % (a.domain, op, b.domain) raise DDMDomainError(msg) if ashape != bshape: msg = "Shape mismatch: %s %s %s" % (a.shape, op, b.shape) raise DDMShapeError(msg) if a.rep.fmt != b.rep.fmt: msg = "Format mismatch: %s %s %s" % (a.rep.fmt, op, b.rep.fmt) raise DDMFormatError(msg) def add(A, B): r""" Adds two DomainMatrix matrices of the same Domain Parameters ========== A, B: DomainMatrix matrices to add Returns ======= DomainMatrix DomainMatrix after Addition Raises ====== ShapeError If the dimensions of the two DomainMatrix are not equal ValueError If the domain of the two DomainMatrix are not same Examples ======== >>> from sympy import ZZ >>> from sympy.polys.matrices import DomainMatrix >>> A = DomainMatrix([ ... [ZZ(1), ZZ(2)], ... [ZZ(3), ZZ(4)]], (2, 2), ZZ) >>> B = DomainMatrix([ ... [ZZ(4), ZZ(3)], ... [ZZ(2), ZZ(1)]], (2, 2), ZZ) >>> A.add(B) DomainMatrix([[5, 5], [5, 5]], (2, 2), ZZ) See Also ======== sub, matmul """ A._check('+', B, A.shape, B.shape) return A.from_rep(A.rep.add(B.rep)) def sub(A, B): r""" Subtracts two DomainMatrix matrices of the same Domain Parameters ========== A, B: DomainMatrix matrices to substract Returns ======= DomainMatrix DomainMatrix after Substraction Raises ====== ShapeError If the dimensions of the two DomainMatrix are not equal ValueError If the domain of the two DomainMatrix are not same Examples ======== >>> from sympy import ZZ >>> from sympy.polys.matrices import DomainMatrix >>> A = DomainMatrix([ ... [ZZ(1), ZZ(2)], ... [ZZ(3), ZZ(4)]], (2, 2), ZZ) >>> B = DomainMatrix([ ... [ZZ(4), ZZ(3)], ... [ZZ(2), ZZ(1)]], (2, 2), ZZ) >>> A.sub(B) DomainMatrix([[-3, -1], [1, 3]], (2, 2), ZZ) See Also ======== add, matmul """ A._check('-', B, A.shape, B.shape) return A.from_rep(A.rep.sub(B.rep)) def neg(A): r""" Returns the negative of DomainMatrix Parameters ========== A : Represents a DomainMatrix Returns ======= DomainMatrix DomainMatrix after Negation Examples ======== >>> from sympy import ZZ >>> from sympy.polys.matrices import DomainMatrix >>> A = DomainMatrix([ ... [ZZ(1), ZZ(2)], ... [ZZ(3), ZZ(4)]], (2, 2), ZZ) >>> A.neg() DomainMatrix([[-1, -2], [-3, -4]], (2, 2), ZZ) """ return A.from_rep(A.rep.neg()) def mul(A, b): r""" Performs term by term multiplication for the second DomainMatrix w.r.t first DomainMatrix. Returns a DomainMatrix whose rows are list of DomainMatrix matrices created after term by term multiplication. Parameters ========== A, B: DomainMatrix matrices to multiply term-wise Returns ======= DomainMatrix DomainMatrix after term by term multiplication Examples ======== >>> from sympy import ZZ >>> from sympy.polys.matrices import DomainMatrix >>> A = DomainMatrix([ ... [ZZ(1), ZZ(2)], ... [ZZ(3), ZZ(4)]], (2, 2), ZZ) >>> B = DomainMatrix([ ... [ZZ(1), ZZ(1)], ... [ZZ(0), ZZ(1)]], (2, 2), ZZ) >>> A.mul(B) DomainMatrix([[DomainMatrix([[1, 1], [0, 1]], (2, 2), ZZ), DomainMatrix([[2, 2], [0, 2]], (2, 2), ZZ)], [DomainMatrix([[3, 3], [0, 3]], (2, 2), ZZ), DomainMatrix([[4, 4], [0, 4]], (2, 2), ZZ)]], (2, 2), ZZ) See Also ======== matmul """ return A.from_rep(A.rep.mul(b)) def matmul(A, B): r""" Performs matrix multiplication of two DomainMatrix matrices Parameters ========== A, B: DomainMatrix to multiply Returns ======= DomainMatrix DomainMatrix after multiplication Examples ======== >>> from sympy import ZZ >>> from sympy.polys.matrices import DomainMatrix >>> A = DomainMatrix([ ... [ZZ(1), ZZ(2)], ... [ZZ(3), ZZ(4)]], (2, 2), ZZ) >>> B = DomainMatrix([ ... [ZZ(1), ZZ(1)], ... [ZZ(0), ZZ(1)]], (2, 2), ZZ) >>> A.matmul(B) DomainMatrix([[1, 3], [3, 7]], (2, 2), ZZ) See Also ======== mul, pow, add, sub """ A._check('*', B, A.shape[1], B.shape[0]) return A.from_rep(A.rep.matmul(B.rep)) def scalarmul(A, lamda): if lamda.element == lamda.domain.zero: m, n = A.shape return DomainMatrix([[lamda.domain.zero]*n]*m, (m, n), A.domain) if lamda.element == lamda.domain.one: return A return A.mul(lamda.element) def __truediv__(A, lamda): """ Method for Scalar Divison""" if isinstance(lamda, int): lamda = DomainScalar(ZZ(lamda), ZZ) if not isinstance(lamda, DomainScalar): return NotImplemented A, lamda = A.to_field().unify(lamda) if lamda.element == lamda.domain.zero: raise ZeroDivisionError if lamda.element == lamda.domain.one: return A.to_field() return A.mul(1 / lamda.element) def pow(A, n): r""" Computes A**n Parameters ========== A : DomainMatrix n : exponent for A Returns ======= DomainMatrix DomainMatrix on computing A**n Raises ====== NotImplementedError if n is negative. Examples ======== >>> from sympy import ZZ >>> from sympy.polys.matrices import DomainMatrix >>> A = DomainMatrix([ ... [ZZ(1), ZZ(1)], ... [ZZ(0), ZZ(1)]], (2, 2), ZZ) >>> A.pow(2) DomainMatrix([[1, 2], [0, 1]], (2, 2), ZZ) See Also ======== matmul """ nrows, ncols = A.shape if nrows != ncols: raise NonSquareMatrixError('Power of a nonsquare matrix') if n < 0: raise NotImplementedError('Negative powers') elif n == 0: return A.eye(nrows, A.domain) elif n == 1: return A elif n % 2 == 1: return A * A**(n - 1) else: sqrtAn = A ** (n // 2) return sqrtAn * sqrtAn def rref(self): r""" Returns reduced-row echelon form and list of pivots for the DomainMatrix Returns ======= (DomainMatrix, list) reduced-row echelon form and list of pivots for the DomainMatrix Raises ====== ValueError If the domain of DomainMatrix not a Field Examples ======== >>> from sympy import QQ >>> from sympy.polys.matrices import DomainMatrix >>> A = DomainMatrix([ ... [QQ(2), QQ(-1), QQ(0)], ... [QQ(-1), QQ(2), QQ(-1)], ... [QQ(0), QQ(0), QQ(2)]], (3, 3), QQ) >>> rref_matrix, rref_pivots = A.rref() >>> rref_matrix DomainMatrix([[1, 0, 0], [0, 1, 0], [0, 0, 1]], (3, 3), QQ) >>> rref_pivots (0, 1, 2) See Also ======== convert_to, lu """ if not self.domain.is_Field: raise ValueError('Not a field') rref_ddm, pivots = self.rep.rref() return self.from_rep(rref_ddm), tuple(pivots) def nullspace(self): r""" Returns the Null Space for the DomainMatrix Returns ======= DomainMatrix Null Space of the DomainMatrix Examples ======== >>> from sympy import QQ >>> from sympy.polys.matrices import DomainMatrix >>> A = DomainMatrix([ ... [QQ(1), QQ(-1)], ... [QQ(2), QQ(-2)]], (2, 2), QQ) >>> A.nullspace() DomainMatrix([[1, 1]], (1, 2), QQ) """ if not self.domain.is_Field: raise ValueError('Not a field') return self.from_rep(self.rep.nullspace()[0]) def inv(self): r""" Finds the inverse of the DomainMatrix if exists Returns ======= DomainMatrix DomainMatrix after inverse Raises ====== ValueError If the domain of DomainMatrix not a Field NonSquareMatrixError If the DomainMatrix is not a not Square DomainMatrix Examples ======== >>> from sympy import QQ >>> from sympy.polys.matrices import DomainMatrix >>> A = DomainMatrix([ ... [QQ(2), QQ(-1), QQ(0)], ... [QQ(-1), QQ(2), QQ(-1)], ... [QQ(0), QQ(0), QQ(2)]], (3, 3), QQ) >>> A.inv() DomainMatrix([[2/3, 1/3, 1/6], [1/3, 2/3, 1/3], [0, 0, 1/2]], (3, 3), QQ) See Also ======== neg """ if not self.domain.is_Field: raise ValueError('Not a field') m, n = self.shape if m != n: raise NonSquareMatrixError inv = self.rep.inv() return self.from_rep(inv) def det(self): r""" Returns the determinant of a Square DomainMatrix Returns ======= S.Complexes determinant of Square DomainMatrix Raises ====== ValueError If the domain of DomainMatrix not a Field Examples ======== >>> from sympy import ZZ >>> from sympy.polys.matrices import DomainMatrix >>> A = DomainMatrix([ ... [ZZ(1), ZZ(2)], ... [ZZ(3), ZZ(4)]], (2, 2), ZZ) >>> A.det() -2 """ m, n = self.shape if m != n: raise NonSquareMatrixError return self.rep.det() def lu(self): r""" Returns Lower and Upper decomposition of the DomainMatrix Returns ======= (L, U, exchange) L, U are Lower and Upper decomposition of the DomainMatrix, exchange is the list of indices of rows exchanged in the decomposition. Raises ====== ValueError If the domain of DomainMatrix not a Field Examples ======== >>> from sympy import QQ >>> from sympy.polys.matrices import DomainMatrix >>> A = DomainMatrix([ ... [QQ(1), QQ(-1)], ... [QQ(2), QQ(-2)]], (2, 2), QQ) >>> A.lu() (DomainMatrix([[1, 0], [2, 1]], (2, 2), QQ), DomainMatrix([[1, -1], [0, 0]], (2, 2), QQ), []) See Also ======== lu_solve """ if not self.domain.is_Field: raise ValueError('Not a field') L, U, swaps = self.rep.lu() return self.from_rep(L), self.from_rep(U), swaps def lu_solve(self, rhs): r""" Solver for DomainMatrix x in the A*x = B Parameters ========== rhs : DomainMatrix B Returns ======= DomainMatrix x in A*x = B Raises ====== ShapeError If the DomainMatrix A and rhs have different number of rows ValueError If the domain of DomainMatrix A not a Field Examples ======== >>> from sympy import QQ >>> from sympy.polys.matrices import DomainMatrix >>> A = DomainMatrix([ ... [QQ(1), QQ(2)], ... [QQ(3), QQ(4)]], (2, 2), QQ) >>> B = DomainMatrix([ ... [QQ(1), QQ(1)], ... [QQ(0), QQ(1)]], (2, 2), QQ) >>> A.lu_solve(B) DomainMatrix([[-2, -1], [3/2, 1]], (2, 2), QQ) See Also ======== lu """ if self.shape[0] != rhs.shape[0]: raise ShapeError("Shape") if not self.domain.is_Field: raise ValueError('Not a field') sol = self.rep.lu_solve(rhs.rep) return self.from_rep(sol) def _solve(A, b): # XXX: Not sure about this method or its signature. It is just created # because it is needed by the holonomic module. if A.shape[0] != b.shape[0]: raise ShapeError("Shape") if A.domain != b.domain or not A.domain.is_Field: raise ValueError('Not a field') Aaug = A.hstack(b) Arref, pivots = Aaug.rref() particular = Arref.from_rep(Arref.rep.particular()) nullspace_rep, nonpivots = Arref[:,:-1].rep.nullspace() nullspace = Arref.from_rep(nullspace_rep) return particular, nullspace def charpoly(self): r""" Returns the coefficients of the characteristic polynomial of the DomainMatrix. These elements will be domain elements. The domain of the elements will be same as domain of the DomainMatrix. Returns ======= list coefficients of the characteristic polynomial Raises ====== NonSquareMatrixError If the DomainMatrix is not a not Square DomainMatrix Examples ======== >>> from sympy import ZZ >>> from sympy.polys.matrices import DomainMatrix >>> A = DomainMatrix([ ... [ZZ(1), ZZ(2)], ... [ZZ(3), ZZ(4)]], (2, 2), ZZ) >>> A.charpoly() [1, -5, -2] """ m, n = self.shape if m != n: raise NonSquareMatrixError("not square") return self.rep.charpoly() @classmethod def eye(cls, n, domain): r""" Return identity matrix of size n Examples ======== >>> from sympy.polys.matrices import DomainMatrix >>> from sympy import QQ >>> DomainMatrix.eye(3, QQ) DomainMatrix({0: {0: 1}, 1: {1: 1}, 2: {2: 1}}, (3, 3), QQ) """ return cls.from_rep(SDM.eye(n, domain)) @classmethod def diag(cls, diagonal, domain, shape=None): r""" Return diagonal matrix with entries from ``diagonal``. Examples ======== >>> from sympy.polys.matrices import DomainMatrix >>> from sympy import ZZ >>> DomainMatrix.diag([ZZ(5), ZZ(6)], ZZ) DomainMatrix({0: {0: 5}, 1: {1: 6}}, (2, 2), ZZ) """ if shape is None: N = len(diagonal) shape = (N, N) return cls.from_rep(SDM.diag(diagonal, domain, shape)) @classmethod def zeros(cls, shape, domain, *, fmt='sparse'): """Returns a zero DomainMatrix of size shape, belonging to the specified domain Examples ======== >>> from sympy.polys.matrices import DomainMatrix >>> from sympy import QQ >>> DomainMatrix.zeros((2, 3), QQ) DomainMatrix({}, (2, 3), QQ) """ return cls.from_rep(SDM.zeros(shape, domain)) @classmethod def ones(cls, shape, domain): """Returns a zero DomainMatrix of size shape, belonging to the specified domain Examples ======== >>> from sympy.polys.matrices import DomainMatrix >>> from sympy import QQ >>> DomainMatrix.ones((2,3), QQ) DomainMatrix([[1, 1, 1], [1, 1, 1]], (2, 3), QQ) """ return cls.from_rep(DDM.ones(shape, domain)) def __eq__(A, B): r""" Checks for two DomainMatrix matrices to be equal or not Parameters ========== A, B: DomainMatrix to check equality Returns ======= Boolean True for equal, else False Raises ====== NotImplementedError If B is not a DomainMatrix Examples ======== >>> from sympy import ZZ >>> from sympy.polys.matrices import DomainMatrix >>> A = DomainMatrix([ ... [ZZ(1), ZZ(2)], ... [ZZ(3), ZZ(4)]], (2, 2), ZZ) >>> B = DomainMatrix([ ... [ZZ(1), ZZ(1)], ... [ZZ(0), ZZ(1)]], (2, 2), ZZ) >>> A.__eq__(A) True >>> A.__eq__(B) False """ if not isinstance(A, type(B)): return NotImplemented return A.domain == B.domain and A.rep == B.rep
49260bd89d6188f0ec53a2bbf6aad5ba8343adb413c69e74ea9e8978f6856560
# # sympy.polys.matrices.linsolve module # # This module defines the _linsolve function which is the internal workhorse # used by linsolve. This computes the solution of a system of linear equations # using the SDM sparse matrix implementation in sympy.polys.matrices.sdm. This # is a replacement for solve_lin_sys in sympy.polys.solvers which is # inefficient for large sparse systems due to the use of a PolyRing with many # generators: # # https://github.com/sympy/sympy/issues/20857 # # The implementation of _linsolve here handles: # # - Extracting the coefficients from the Expr/Eq input equations. # - Constructing a domain and converting the coefficients to # that domain. # - Using the SDM.rref, SDM.nullspace etc methods to generate the full # solution working with arithmetic only in the domain of the coefficients. # # The routines here are particularly designed to be efficient for large sparse # systems of linear equations although as well as dense systems. It is # possible that for some small dense systems solve_lin_sys which uses the # dense matrix implementation DDM will be more efficient. With smaller systems # though the bulk of the time is spent just preprocessing the inputs and the # relative time spent in rref is too small to be noticeable. # from collections import defaultdict from sympy.core.add import Add from sympy.core.mul import Mul from sympy.core.singleton import S from sympy.polys.constructor import construct_domain from sympy.polys.solvers import PolyNonlinearError from .sdm import ( SDM, sdm_irref, sdm_particular_from_rref, sdm_nullspace_from_rref ) def _linsolve(eqs, syms): """Solve a linear system of equations. Examples ======== Solve a linear system with a unique solution: >>> from sympy import symbols, Eq >>> from sympy.polys.matrices.linsolve import _linsolve >>> x, y = symbols('x, y') >>> eqs = [Eq(x + y, 1), Eq(x - y, 2)] >>> _linsolve(eqs, [x, y]) {x: 3/2, y: -1/2} In the case of underdetermined systems the solution will be expressed in terms of the unknown symbols that are unconstrained: >>> _linsolve([Eq(x + y, 0)], [x, y]) {x: -y, y: y} """ # Number of unknowns (columns in the non-augmented matrix) nsyms = len(syms) # Convert to sparse augmented matrix (len(eqs) x (nsyms+1)) eqsdict, rhs = _linear_eq_to_dict(eqs, syms) Aaug = sympy_dict_to_dm(eqsdict, rhs, syms) K = Aaug.domain # sdm_irref has issues with float matrices. This uses the ddm_rref() # function. When sdm_rref() can handle float matrices reasonably this # should be removed... if K.is_RealField or K.is_ComplexField: Aaug = Aaug.to_ddm().rref()[0].to_sdm() # Compute reduced-row echelon form (RREF) Arref, pivots, nzcols = sdm_irref(Aaug) # No solution: if pivots and pivots[-1] == nsyms: return None # Particular solution for non-homogeneous system: P = sdm_particular_from_rref(Arref, nsyms+1, pivots) # Nullspace - general solution to homogeneous system # Note: using nsyms not nsyms+1 to ignore last column V, nonpivots = sdm_nullspace_from_rref(Arref, K.one, nsyms, pivots, nzcols) # Collect together terms from particular and nullspace: sol = defaultdict(list) for i, v in P.items(): sol[syms[i]].append(K.to_sympy(v)) for npi, Vi in zip(nonpivots, V): sym = syms[npi] for i, v in Vi.items(): sol[syms[i]].append(sym * K.to_sympy(v)) # Use a single call to Add for each term: sol = {s: Add(*terms) for s, terms in sol.items()} # Fill in the zeros: zero = S.Zero for s in set(syms) - set(sol): sol[s] = zero # All done! return sol def sympy_dict_to_dm(eqs_coeffs, eqs_rhs, syms): """Convert a system of dict equations to a sparse augmented matrix""" elems = set(eqs_rhs).union(*(e.values() for e in eqs_coeffs)) K, elems_K = construct_domain(elems, field=True, extension=True) elem_map = dict(zip(elems, elems_K)) neqs = len(eqs_coeffs) nsyms = len(syms) sym2index = dict(zip(syms, range(nsyms))) eqsdict = [] for eq, rhs in zip(eqs_coeffs, eqs_rhs): eqdict = {sym2index[s]: elem_map[c] for s, c in eq.items()} if rhs: eqdict[nsyms] = - elem_map[rhs] if eqdict: eqsdict.append(eqdict) sdm_aug = SDM(enumerate(eqsdict), (neqs, nsyms+1), K) return sdm_aug def _expand_eqs_deprecated(eqs): """Use expand to cancel nonlinear terms. This approach matches previous behaviour of linsolve but should be deprecated. """ def expand_eq(eq): if eq.is_Equality: eq = eq.lhs - eq.rhs return eq.expand() return [expand_eq(eq) for eq in eqs] def _linear_eq_to_dict(eqs, syms): """Convert a system Expr/Eq equations into dict form""" try: return _linear_eq_to_dict_inner(eqs, syms) except PolyNonlinearError: # XXX: This should be deprecated: eqs = _expand_eqs_deprecated(eqs) return _linear_eq_to_dict_inner(eqs, syms) def _linear_eq_to_dict_inner(eqs, syms): """Convert a system Expr/Eq equations into dict form""" syms = set(syms) eqsdict, eqs_rhs = [], [] for eq in eqs: rhs, eqdict = _lin_eq2dict(eq, syms) eqsdict.append(eqdict) eqs_rhs.append(rhs) return eqsdict, eqs_rhs def _lin_eq2dict(a, symset): """Efficiently convert a linear equation to a dict of coefficients""" if a in symset: return S.Zero, {a: S.One} elif a.is_Add: terms_list = defaultdict(list) coeff_list = [] for ai in a.args: ci, ti = _lin_eq2dict(ai, symset) coeff_list.append(ci) for mij, cij in ti.items(): terms_list[mij].append(cij) coeff = Add(*coeff_list) terms = {sym: Add(*coeffs) for sym, coeffs in terms_list.items()} return coeff, terms elif a.is_Mul: terms = terms_coeff = None coeff_list = [] for ai in a.args: ci, ti = _lin_eq2dict(ai, symset) if not ti: coeff_list.append(ci) elif terms is None: terms = ti terms_coeff = ci else: raise PolyNonlinearError coeff = Mul(*coeff_list) if terms is None: return coeff, {} else: terms = {sym: coeff * c for sym, c in terms.items()} return coeff * terms_coeff, terms elif a.is_Equality: return _lin_eq2dict(a.lhs - a.rhs, symset) elif not a.free_symbols & symset: return a, {} else: raise PolyNonlinearError
8c8857c33f9d2def141463457b13a48960eddf77b5168ef14ba19ddeddc5cdc7
""" Module for the SDM class. """ from operator import add, neg, pos, sub from collections import defaultdict from .exceptions import DDMBadInputError, DDMDomainError, DDMShapeError from .ddm import DDM class SDM(dict): r"""Sparse matrix based on polys domain elements This is a dict subclass and is a wrapper for a dict of dicts that supports basic matrix arithmetic +, -, *, **. In order to create a new :py:class:`~.SDM`, a dict of dicts mapping non-zero elements to their corresponding row and column in the matrix is needed. We also need to specify the shape and :py:class:`~.Domain` of our :py:class:`~.SDM` object. We declare a 2x2 :py:class:`~.SDM` matrix belonging to QQ domain as shown below. The 2x2 Matrix in the example is .. math:: A = \left[\begin{array}{ccc} 0 & \frac{1}{2} \\ 0 & 0 \end{array} \right] >>> from sympy.polys.matrices.sdm import SDM >>> from sympy import QQ >>> elemsdict = {0:{1:QQ(1, 2)}} >>> A = SDM(elemsdict, (2, 2), QQ) >>> A {0: {1: 1/2}} We can manipulate :py:class:`~.SDM` the same way as a Matrix class >>> from sympy import ZZ >>> A = SDM({0:{1: ZZ(2)}, 1:{0:ZZ(1)}}, (2, 2), ZZ) >>> B = SDM({0:{0: ZZ(3)}, 1:{1:ZZ(4)}}, (2, 2), ZZ) >>> A + B {0: {0: 3, 1: 2}, 1: {0: 1, 1: 4}} Multiplication >>> A*B {0: {1: 8}, 1: {0: 3}} >>> A*ZZ(2) {0: {1: 4}, 1: {0: 2}} """ fmt = 'sparse' def __init__(self, elemsdict, shape, domain): super().__init__(elemsdict) self.shape = self.rows, self.cols = m, n = shape self.domain = domain if not all(0 <= r < m for r in self): raise DDMBadInputError("Row out of range") if not all(0 <= c < n for row in self.values() for c in row): raise DDMBadInputError("Column out of range") def getitem(self, i, j): try: return self[i][j] except KeyError: m, n = self.shape if -m <= i < m and -n <= j < n: try: return self[i % m][j % n] except KeyError: return self.domain.zero else: raise IndexError("index out of range") def extract_slice(self, slice1, slice2): m, n = self.shape ri = range(m)[slice1] ci = range(n)[slice2] sdm = {} for i, row in self.items(): if i in ri: row = {ci.index(j): e for j, e in row.items() if j in ci} if row: sdm[ri.index(i)] = row return self.new(sdm, (len(ri), len(ci)), self.domain) def __str__(self): rowsstr = [] for i, row in self.items(): elemsstr = ', '.join('%s: %s' % (j, elem) for j, elem in row.items()) rowsstr.append('%s: {%s}' % (i, elemsstr)) return '{%s}' % ', '.join(rowsstr) def __repr__(self): cls = type(self).__name__ rows = dict.__repr__(self) return '%s(%s, %s, %s)' % (cls, rows, self.shape, self.domain) @classmethod def new(cls, sdm, shape, domain): """ Parameters ========== sdm: A dict of dicts for non-zero elements in SDM shape: tuple representing dimension of SDM domain: Represents :py:class:`~.Domain` of SDM Returns ======= An :py:class:`~.SDM` object Examples ======== >>> from sympy.polys.matrices.sdm import SDM >>> from sympy import QQ >>> elemsdict = {0:{1: QQ(2)}} >>> A = SDM.new(elemsdict, (2, 2), QQ) >>> A {0: {1: 2}} """ return cls(sdm, shape, domain) def copy(A): """ Returns the copy of a :py:class:`~.SDM` object Examples ======== >>> from sympy.polys.matrices.sdm import SDM >>> from sympy import QQ >>> elemsdict = {0:{1:QQ(2)}, 1:{}} >>> A = SDM(elemsdict, (2, 2), QQ) >>> B = A.copy() >>> B {0: {1: 2}, 1: {}} """ Ac = {i: Ai.copy() for i, Ai in A.items()} return A.new(Ac, A.shape, A.domain) @classmethod def from_list(cls, ddm, shape, domain): """ Parameters ========== ddm: list of lists containing domain elements shape: Dimensions of :py:class:`~.SDM` matrix domain: Represents :py:class:`~.Domain` of :py:class:`~.SDM` object Returns ======= :py:class:`~.SDM` containing elements of ddm Examples ======== >>> from sympy.polys.matrices.sdm import SDM >>> from sympy import QQ >>> ddm = [[QQ(1, 2), QQ(0)], [QQ(0), QQ(3, 4)]] >>> A = SDM.from_list(ddm, (2, 2), QQ) >>> A {0: {0: 1/2}, 1: {1: 3/4}} """ m, n = shape if not (len(ddm) == m and all(len(row) == n for row in ddm)): raise DDMBadInputError("Inconsistent row-list/shape") getrow = lambda i: {j:ddm[i][j] for j in range(n) if ddm[i][j]} irows = ((i, getrow(i)) for i in range(m)) sdm = {i: row for i, row in irows if row} return cls(sdm, shape, domain) @classmethod def from_ddm(cls, ddm): """ converts object of :py:class:`~.DDM` to :py:class:`~.SDM` Examples ======== >>> from sympy.polys.matrices.ddm import DDM >>> from sympy.polys.matrices.sdm import SDM >>> from sympy import QQ >>> ddm = DDM( [[QQ(1, 2), 0], [0, QQ(3, 4)]], (2, 2), QQ) >>> A = SDM.from_ddm(ddm) >>> A {0: {0: 1/2}, 1: {1: 3/4}} """ return cls.from_list(ddm, ddm.shape, ddm.domain) def to_list(M): """ Converts a :py:class:`~.SDM` object to a list Examples ======== >>> from sympy.polys.matrices.sdm import SDM >>> from sympy import QQ >>> elemsdict = {0:{1:QQ(2)}, 1:{}} >>> A = SDM(elemsdict, (2, 2), QQ) >>> A.to_list() [[0, 2], [0, 0]] """ m, n = M.shape zero = M.domain.zero ddm = [[zero] * n for _ in range(m)] for i, row in M.items(): for j, e in row.items(): ddm[i][j] = e return ddm def to_ddm(M): """ Convert a :py:class:`~.SDM` object to a :py:class:`~.DDM` object Examples ======== >>> from sympy.polys.matrices.sdm import SDM >>> from sympy import QQ >>> A = SDM({0:{1:QQ(2)}, 1:{}}, (2, 2), QQ) >>> A.to_ddm() [[0, 2], [0, 0]] """ return DDM(M.to_list(), M.shape, M.domain) def to_sdm(M): return M @classmethod def zeros(cls, shape, domain): r""" Returns a :py:class:`~.SDM` of size shape, belonging to the specified domain In the example below we declare a matrix A where, .. math:: A := \left[\begin{array}{ccc} 0 & 0 & 0 \\ 0 & 0 & 0 \end{array} \right] >>> from sympy.polys.matrices.sdm import SDM >>> from sympy import QQ >>> A = SDM.zeros((2, 3), QQ) >>> A {} """ return cls({}, shape, domain) @classmethod def ones(cls, shape, domain): one = domain.one m, n = shape row = dict(zip(range(n), [one]*n)) sdm = {i: row.copy() for i in range(m)} return cls(sdm, shape, domain) @classmethod def eye(cls, size, domain): """ Returns a identity :py:class:`~.SDM` matrix of dimensions size x size, belonging to the specified domain Examples ======== >>> from sympy.polys.matrices.sdm import SDM >>> from sympy import QQ >>> I = SDM.eye(2, QQ) >>> I {0: {0: 1}, 1: {1: 1}} """ one = domain.one sdm = {i: {i: one} for i in range(size)} return cls(sdm, (size, size), domain) @classmethod def diag(cls, diagonal, domain, shape): sdm = {i: {i: v} for i, v in enumerate(diagonal) if v} return cls(sdm, shape, domain) def transpose(M): """ Returns the transpose of a :py:class:`~.SDM` matrix Examples ======== >>> from sympy.polys.matrices.sdm import SDM >>> from sympy import QQ >>> A = SDM({0:{1:QQ(2)}, 1:{}}, (2, 2), QQ) >>> A.transpose() {1: {0: 2}} """ MT = sdm_transpose(M) return M.new(MT, M.shape[::-1], M.domain) def __add__(A, B): if not isinstance(B, SDM): return NotImplemented return A.add(B) def __sub__(A, B): if not isinstance(B, SDM): return NotImplemented return A.sub(B) def __neg__(A): return A.neg() def __mul__(A, B): """A * B""" if isinstance(B, SDM): return A.matmul(B) elif B in A.domain: return A.mul(B) else: return NotImplemented def __rmul__(a, b): if b in a.domain: return a.mul(b) else: return NotImplemented def matmul(A, B): """ Performs matrix multiplication of two SDM matrices Parameters ========== A, B: SDM to multiply Returns ======= SDM SDM after multiplication Raises ====== DomainError If domain of A does not match with that of B Examples ======== >>> from sympy import ZZ >>> from sympy.polys.matrices.sdm import SDM >>> A = SDM({0:{1: ZZ(2)}, 1:{0:ZZ(1)}}, (2, 2), ZZ) >>> B = SDM({0:{0:ZZ(2), 1:ZZ(3)}, 1:{0:ZZ(4)}}, (2, 2), ZZ) >>> A.matmul(B) {0: {0: 8}, 1: {0: 2, 1: 3}} """ if A.domain != B.domain: raise DDMDomainError m, n = A.shape n2, o = B.shape if n != n2: raise DDMShapeError C = sdm_matmul(A, B) return A.new(C, (m, o), A.domain) def mul(A, b): """ Multiplies each element of A with a scalar b Examples ======== >>> from sympy import ZZ >>> from sympy.polys.matrices.sdm import SDM >>> A = SDM({0:{1: ZZ(2)}, 1:{0:ZZ(1)}}, (2, 2), ZZ) >>> A.mul(ZZ(3)) {0: {1: 6}, 1: {0: 3}} """ Csdm = unop_dict(A, lambda aij: aij*b) return A.new(Csdm, A.shape, A.domain) def add(A, B): """ Adds two :py:class:`~.SDM` matrices Examples ======== >>> from sympy import ZZ >>> from sympy.polys.matrices.sdm import SDM >>> A = SDM({0:{1: ZZ(2)}, 1:{0:ZZ(1)}}, (2, 2), ZZ) >>> B = SDM({0:{0: ZZ(3)}, 1:{1:ZZ(4)}}, (2, 2), ZZ) >>> A.add(B) {0: {0: 3, 1: 2}, 1: {0: 1, 1: 4}} """ Csdm = binop_dict(A, B, add, pos, pos) return A.new(Csdm, A.shape, A.domain) def sub(A, B): """ Subtracts two :py:class:`~.SDM` matrices Examples ======== >>> from sympy import ZZ >>> from sympy.polys.matrices.sdm import SDM >>> A = SDM({0:{1: ZZ(2)}, 1:{0:ZZ(1)}}, (2, 2), ZZ) >>> B = SDM({0:{0: ZZ(3)}, 1:{1:ZZ(4)}}, (2, 2), ZZ) >>> A.sub(B) {0: {0: -3, 1: 2}, 1: {0: 1, 1: -4}} """ Csdm = binop_dict(A, B, sub, pos, neg) return A.new(Csdm, A.shape, A.domain) def neg(A): """ Returns the negative of a :py:class:`~.SDM` matrix Examples ======== >>> from sympy import ZZ >>> from sympy.polys.matrices.sdm import SDM >>> A = SDM({0:{1: ZZ(2)}, 1:{0:ZZ(1)}}, (2, 2), ZZ) >>> A.neg() {0: {1: -2}, 1: {0: -1}} """ Csdm = unop_dict(A, neg) return A.new(Csdm, A.shape, A.domain) def convert_to(A, K): """ Converts the :py:class:`~.Domain` of a :py:class:`~.SDM` matrix to K Examples ======== >>> from sympy import ZZ, QQ >>> from sympy.polys.matrices.sdm import SDM >>> A = SDM({0:{1: ZZ(2)}, 1:{0:ZZ(1)}}, (2, 2), ZZ) >>> A.convert_to(QQ) {0: {1: 2}, 1: {0: 1}} """ Kold = A.domain if K == Kold: return A.copy() Ak = unop_dict(A, lambda e: K.convert_from(e, Kold)) return A.new(Ak, A.shape, K) def rref(A): """ Returns reduced-row echelon form and list of pivots for the :py:class:`~.SDM` Examples ======== >>> from sympy import QQ >>> from sympy.polys.matrices.sdm import SDM >>> A = SDM({0:{0:QQ(1), 1:QQ(2)}, 1:{0:QQ(2), 1:QQ(4)}}, (2, 2), QQ) >>> A.rref() ({0: {0: 1, 1: 2}}, [0]) """ B, pivots, _ = sdm_irref(A) return A.new(B, A.shape, A.domain), pivots def inv(A): """ Returns inverse of a matrix A Examples ======== >>> from sympy import QQ >>> from sympy.polys.matrices.sdm import SDM >>> A = SDM({0:{0:QQ(1), 1:QQ(2)}, 1:{0:QQ(3), 1:QQ(4)}}, (2, 2), QQ) >>> A.inv() {0: {0: -2, 1: 1}, 1: {0: 3/2, 1: -1/2}} """ return A.from_ddm(A.to_ddm().inv()) def det(A): """ Returns determinant of A Examples ======== >>> from sympy import QQ >>> from sympy.polys.matrices.sdm import SDM >>> A = SDM({0:{0:QQ(1), 1:QQ(2)}, 1:{0:QQ(3), 1:QQ(4)}}, (2, 2), QQ) >>> A.det() -2 """ return A.to_ddm().det() def lu(A): """ Returns LU decomposition for a matrix A Examples ======== >>> from sympy import QQ >>> from sympy.polys.matrices.sdm import SDM >>> A = SDM({0:{0:QQ(1), 1:QQ(2)}, 1:{0:QQ(3), 1:QQ(4)}}, (2, 2), QQ) >>> A.lu() ({0: {0: 1}, 1: {0: 3, 1: 1}}, {0: {0: 1, 1: 2}, 1: {1: -2}}, []) """ L, U, swaps = A.to_ddm().lu() return A.from_ddm(L), A.from_ddm(U), swaps def lu_solve(A, b): """ Uses LU decomposition to solve Ax = b, Examples ======== >>> from sympy import QQ >>> from sympy.polys.matrices.sdm import SDM >>> A = SDM({0:{0:QQ(1), 1:QQ(2)}, 1:{0:QQ(3), 1:QQ(4)}}, (2, 2), QQ) >>> b = SDM({0:{0:QQ(1)}, 1:{0:QQ(2)}}, (2, 1), QQ) >>> A.lu_solve(b) {1: {0: 1/2}} """ return A.from_ddm(A.to_ddm().lu_solve(b.to_ddm())) def nullspace(A): """ Returns nullspace for a :py:class:`~.SDM` matrix A Examples ======== >>> from sympy import QQ >>> from sympy.polys.matrices.sdm import SDM >>> A = SDM({0:{0:QQ(1), 1:QQ(2)}, 1:{0: QQ(2), 1: QQ(4)}}, (2, 2), QQ) >>> A.nullspace() ({0: {0: -2, 1: 1}}, [1]) """ ncols = A.shape[1] one = A.domain.one B, pivots, nzcols = sdm_irref(A) K, nonpivots = sdm_nullspace_from_rref(B, one, ncols, pivots, nzcols) K = dict(enumerate(K)) shape = (len(K), ncols) return A.new(K, shape, A.domain), nonpivots def particular(A): ncols = A.shape[1] B, pivots, nzcols = sdm_irref(A) P = sdm_particular_from_rref(B, ncols, pivots) rep = {0:P} if P else {} return A.new(rep, (1, ncols-1), A.domain) def hstack(A, *B): """ Horizontally stacks two :py:class:`~.SDM` matrices A & B Examples ======== >>> from sympy import QQ >>> from sympy.polys.matrices.sdm import SDM >>> B = SDM({0:{0:QQ(1)}, 1:{0:QQ(2)}}, (2, 1), QQ) >>> A = SDM({0:{0:QQ(1), 1:QQ(2)}, 1:{0:QQ(3), 1:QQ(4)}}, (2, 2), QQ) >>> A.hstack(B) {0: {0: 1, 1: 2, 2: 1}, 1: {0: 3, 1: 4, 2: 2}} """ Anew = dict(A.copy()) rows, cols = A.shape domain = A.domain for Bk in B: Bkrows, Bkcols = Bk.shape assert Bkrows == rows assert Bk.domain == domain for i, Bki in Bk.items(): Ai = Anew.get(i, None) if Ai is None: Anew[i] = Ai = {} for j, Bkij in Bki.items(): Ai[j + cols] = Bkij cols += Bkcols return A.new(Anew, (rows, cols), A.domain) def vstack(A, *B): Anew = dict(A.copy()) rows, cols = A.shape domain = A.domain for Bk in B: Bkrows, Bkcols = Bk.shape assert Bkcols == cols assert Bk.domain == domain for i, Bki in Bk.items(): Anew[i + rows] = Bki rows += Bkrows return A.new(Anew, (rows, cols), A.domain) def applyfunc(self, func, domain): sdm = {i: {j: func(e) for j, e in row.items()} for i, row in self.items()} return self.new(sdm, self.shape, domain) def charpoly(A): """ Returns the coefficients of the characteristic polynomial of the :py:class:`~.SDM` matrix. These elements will be domain elements. The domain of the elements will be same as domain of the :py:class:`~.SDM`. Examples ======== >>> from sympy import QQ, Symbol >>> from sympy.polys.matrices.sdm import SDM >>> from sympy.polys import Poly >>> A = SDM({0:{0:QQ(1), 1:QQ(2)}, 1:{0:QQ(3), 1:QQ(4)}}, (2, 2), QQ) >>> A.charpoly() [1, -5, -2] We can create a polynomial using the coefficients using :py:class:`~.Poly` >>> x = Symbol('x') >>> p = Poly(A.charpoly(), x, domain=A.domain) >>> p Poly(x**2 - 5*x - 2, x, domain='QQ') """ return A.to_ddm().charpoly() def binop_dict(A, B, fab, fa, fb): Anz, Bnz = set(A), set(B) C = {} for i in Anz & Bnz: Ai, Bi = A[i], B[i] Ci = {} Anzi, Bnzi = set(Ai), set(Bi) for j in Anzi & Bnzi: elem = fab(Ai[j], Bi[j]) if elem: Ci[j] = elem for j in Anzi - Bnzi: Ci[j] = fa(Ai[j]) for j in Bnzi - Anzi: Ci[j] = fb(Bi[j]) if Ci: C[i] = Ci for i in Anz - Bnz: Ai = A[i] C[i] = {j: fa(Aij) for j, Aij in Ai.items()} for i in Bnz - Anz: Bi = B[i] C[i] = {j: fb(Bij) for j, Bij in Bi.items()} return C def unop_dict(A, f): B = {} for i, Ai in A.items(): Bi = {} for j, Aij in Ai.items(): Bij = f(Aij) if Bij: Bi[j] = Bij if Bi: B[i] = Bi return B def sdm_transpose(M): MT = {} for i, Mi in M.items(): for j, Mij in Mi.items(): try: MT[j][i] = Mij except KeyError: MT[j] = {i: Mij} return MT def sdm_matmul(A, B): # # Should be fast if A and B are very sparse. # Consider e.g. A = B = eye(1000). # # The idea here is that we compute C = A*B in terms of the rows of C and # B since the dict of dicts representation naturally stores the matrix as # rows. The ith row of C (Ci) is equal to the sum of Aik * Bk where Bk is # the kth row of B. The algorithm below loops over each nonzero element # Aik of A and if the corresponding row Bj is nonzero then we do # Ci += Aik * Bk. # To make this more efficient we don't need to loop over all elements Aik. # Instead for each row Ai we compute the intersection of the nonzero # columns in Ai with the nonzero rows in B. That gives the k such that # Aik and Bk are both nonzero. In Python the intersection of two sets # of int can be computed very efficiently. # C = {} B_knz = set(B) for i, Ai in A.items(): Ci = {} Ai_knz = set(Ai) for k in Ai_knz & B_knz: Aik = Ai[k] for j, Bkj in B[k].items(): Cij = Ci.get(j, None) if Cij is not None: Cij = Cij + Aik * Bkj if Cij: Ci[j] = Cij else: Ci.pop(j) else: Cij = Aik * Bkj if Cij: Ci[j] = Cij if Ci: C[i] = Ci return C def sdm_irref(A): """RREF and pivots of a sparse matrix *A*. Compute the reduced row echelon form (RREF) of the matrix *A* and return a list of the pivot columns. This routine does not work in place and leaves the original matrix *A* unmodified. Examples ======== This routine works with a dict of dicts sparse representation of a matrix: >>> from sympy import QQ >>> from sympy.polys.matrices.sdm import sdm_irref >>> A = {0: {0: QQ(1), 1: QQ(2)}, 1: {0: QQ(3), 1: QQ(4)}} >>> Arref, pivots, _ = sdm_irref(A) >>> Arref {0: {0: 1}, 1: {1: 1}} >>> pivots [0, 1] The analogous calculation with :py:class:`~.Matrix` would be >>> from sympy import Matrix >>> M = Matrix([[1, 2], [3, 4]]) >>> Mrref, pivots = M.rref() >>> Mrref Matrix([ [1, 0], [0, 1]]) >>> pivots (0, 1) Notes ===== The cost of this algorithm is determined purely by the nonzero elements of the matrix. No part of the cost of any step in this algorithm depends on the number of rows or columns in the matrix. No step depends even on the number of nonzero rows apart from the primary loop over those rows. The implementation is much faster than ddm_rref for sparse matrices. In fact at the time of writing it is also (slightly) faster than the dense implementation even if the input is a fully dense matrix so it seems to be faster in all cases. The elements of the matrix should support exact division with ``/``. For example elements of any domain that is a field (e.g. ``QQ``) should be fine. No attempt is made to handle inexact arithmetic. """ # # Any zeros in the matrix are not stored at all so an element is zero if # its row dict has no index at that key. A row is entirely zero if its # row index is not in the outer dict. Since rref reorders the rows and # removes zero rows we can completely discard the row indices. The first # step then copies the row dicts into a list sorted by the index of the # first nonzero column in each row. # # The algorithm then processes each row Ai one at a time. Previously seen # rows are used to cancel their pivot columns from Ai. Then a pivot from # Ai is chosen and is cancelled from all previously seen rows. At this # point Ai joins the previously seen rows. Once all rows are seen all # elimination has occurred and the rows are sorted by pivot column index. # # The previously seen rows are stored in two separate groups. The reduced # group consists of all rows that have been reduced to a single nonzero # element (the pivot). There is no need to attempt any further reduction # with these. Rows that still have other nonzeros need to be considered # when Ai is cancelled from the previously seen rows. # # A dict nonzerocolumns is used to map from a column index to a set of # previously seen rows that still have a nonzero element in that column. # This means that we can cancel the pivot from Ai into the previously seen # rows without needing to loop over each row that might have a zero in # that column. # # Row dicts sorted by index of first nonzero column # (Maybe sorting is not needed/useful.) Arows = sorted((Ai.copy() for Ai in A.values()), key=min) # Each processed row has an associated pivot column. # pivot_row_map maps from the pivot column index to the row dict. # This means that we can represent a set of rows purely as a set of their # pivot indices. pivot_row_map = {} # Set of pivot indices for rows that are fully reduced to a single nonzero. reduced_pivots = set() # Set of pivot indices for rows not fully reduced nonreduced_pivots = set() # Map from column index to a set of pivot indices representing the rows # that have a nonzero at that column. nonzero_columns = defaultdict(set) while Arows: # Select pivot element and row Ai = Arows.pop() # Nonzero columns from fully reduced pivot rows can be removed Ai = {j: Aij for j, Aij in Ai.items() if j not in reduced_pivots} # Others require full row cancellation for j in nonreduced_pivots & set(Ai): Aj = pivot_row_map[j] Aij = Ai[j] Ainz = set(Ai) Ajnz = set(Aj) for k in Ajnz - Ainz: Ai[k] = - Aij * Aj[k] Ai.pop(j) Ainz.remove(j) for k in Ajnz & Ainz: Aik = Ai[k] - Aij * Aj[k] if Aik: Ai[k] = Aik else: Ai.pop(k) # We have now cancelled previously seen pivots from Ai. # If it is zero then discard it. if not Ai: continue # Choose a pivot from Ai: j = min(Ai) Aij = Ai[j] pivot_row_map[j] = Ai Ainz = set(Ai) # Normalise the pivot row to make the pivot 1. # # This approach is slow for some domains. Cross cancellation might be # better for e.g. QQ(x) with division delayed to the final steps. Aijinv = Aij**-1 for l in Ai: Ai[l] *= Aijinv # Use Aij to cancel column j from all previously seen rows for k in nonzero_columns.pop(j, ()): Ak = pivot_row_map[k] Akj = Ak[j] Aknz = set(Ak) for l in Ainz - Aknz: Ak[l] = - Akj * Ai[l] nonzero_columns[l].add(k) Ak.pop(j) Aknz.remove(j) for l in Ainz & Aknz: Akl = Ak[l] - Akj * Ai[l] if Akl: Ak[l] = Akl else: # Drop nonzero elements Ak.pop(l) if l != j: nonzero_columns[l].remove(k) if len(Ak) == 1: reduced_pivots.add(k) nonreduced_pivots.remove(k) if len(Ai) == 1: reduced_pivots.add(j) else: nonreduced_pivots.add(j) for l in Ai: if l != j: nonzero_columns[l].add(j) # All done! pivots = sorted(reduced_pivots | nonreduced_pivots) pivot2row = {p: n for n, p in enumerate(pivots)} nonzero_columns = {c: set(pivot2row[p] for p in s) for c, s in nonzero_columns.items()} rows = [pivot_row_map[i] for i in pivots] rref = dict(enumerate(rows)) return rref, pivots, nonzero_columns def sdm_nullspace_from_rref(A, one, ncols, pivots, nonzero_cols): """Get nullspace from A which is in RREF""" nonpivots = sorted(set(range(ncols)) - set(pivots)) K = [] for j in nonpivots: Kj = {j:one} for i in nonzero_cols.get(j, ()): Kj[pivots[i]] = -A[i][j] K.append(Kj) return K, nonpivots def sdm_particular_from_rref(A, ncols, pivots): """Get a particular solution from A which is in RREF""" P = {} for i, j in enumerate(pivots): Ain = A[i].get(ncols-1, None) if Ain is not None: P[j] = Ain / A[i][j] return P
ce8b0e41f2de2ac32902fd6c9be2473e778698c4de10bbc096837128c919f14a
""" Module for the DomainScalar class. A DomainScalar represents an element which is in a particular Domain. The idea is that the DomainScalar class provides the convenience routines for unifying elements with different domains. It assists in Scalar Multiplication and getitem for DomainMatrix. """ from ..constructor import construct_domain from sympy.polys.domains import Domain, ZZ class DomainScalar: r""" docstring """ def __new__(cls, element, domain): if not isinstance(domain, Domain): raise TypeError("domain should be of type Domain") if not domain.of_type(element): raise TypeError("element %s should be in domain %s" % (element, domain)) return cls.new(element, domain) @classmethod def new(cls, element, domain): obj = super().__new__(cls) obj.element = element obj.domain = domain return obj def __repr__(self): return repr(self.element) @classmethod def from_sympy(cls, expr): [domain, [element]] = construct_domain([expr]) return cls.new(element, domain) def to_sympy(self): return self.domain.to_sympy(self.element) def to_domain(self, domain): element = domain.convert_from(self.element, self.domain) return self.new(element, domain) def convert_to(self, domain): return self.to_domain(domain) def unify(self, other): domain = self.domain.unify(other.domain) return self.to_domain(domain), other.to_domain(domain) def __add__(self, other): if not isinstance(other, DomainScalar): return NotImplemented self, other = self.unify(other) return self.new(self.element + other.element, self.domain) def __sub__(self, other): if not isinstance(other, DomainScalar): return NotImplemented self, other = self.unify(other) return self.new(self.element - other.element, self.domain) def __mul__(self, other): if not isinstance(other, DomainScalar): if isinstance(other, int): other = DomainScalar(ZZ(other), ZZ) else: return NotImplemented self, other = self.unify(other) return self.new(self.element * other.element, self.domain) def __floordiv__(self, other): if not isinstance(other, DomainScalar): return NotImplemented self, other = self.unify(other) return self.new(self.domain.quo(self.element, other.element), self.domain) def __mod__(self, other): if not isinstance(other, DomainScalar): return NotImplemented self, other = self.unify(other) return self.new(self.domain.rem(self.element, other.element), self.domain) def __divmod__(self, other): if not isinstance(other, DomainScalar): return NotImplemented self, other = self.unify(other) q, r = self.domain.div(self.element, other.element) return (self.new(q, self.domain), self.new(r, self.domain)) def __pow__(self, n): if not isinstance(n, int): return NotImplemented return self.new(self.element**n, self.domain) def __pos__(self): return self.new(+self.element, self.domain) def __eq__(self, other): if not isinstance(other, DomainScalar): return NotImplemented return self.element == other.element and self.domain == other.domain def is_zero(self): return self.element == self.domain.zero def is_one(self): return self.element == self.domain.one
154700b180ccddcc63d694bbea0fd7d92ceff602f967998557cb752e0928c91f
""" Module for the ddm_* routines for operating on a matrix in list of lists matrix representation. These routines are used internally by the DDM class which also provides a friendlier interface for them. The idea here is to implement core matrix routines in a way that can be applied to any simple list representation without the need to use any particular matrix class. For example we can compute the RREF of a matrix like: >>> from sympy.polys.matrices.dense import ddm_irref >>> M = [[1, 2, 3], [4, 5, 6]] >>> pivots = ddm_irref(M) >>> M [[1.0, 0.0, -1.0], [0, 1.0, 2.0]] These are lower-level routines that work mostly in place.The routines at this level should not need to know what the domain of the elements is but should ideally document what operations they will use and what functions they need to be provided with. The next-level up is the DDM class which uses these routines but wraps them up with an interface that handles copying etc and keeps track of the Domain of the elements of the matrix: >>> from sympy.polys.domains import QQ >>> from sympy.polys.matrices.ddm import DDM >>> M = DDM([[QQ(1), QQ(2), QQ(3)], [QQ(4), QQ(5), QQ(6)]], (2, 3), QQ) >>> M [[1, 2, 3], [4, 5, 6]] >>> Mrref, pivots = M.rref() >>> Mrref [[1, 0, -1], [0, 1, 2]] """ from operator import mul from .exceptions import ( DDMShapeError, NonInvertibleMatrixError, NonSquareMatrixError, ) def ddm_transpose(a): """matrix transpose""" aT = list(map(list, zip(*a))) return aT def ddm_iadd(a, b): """a += b""" for ai, bi in zip(a, b): for j, bij in enumerate(bi): ai[j] += bij def ddm_isub(a, b): """a -= b""" for ai, bi in zip(a, b): for j, bij in enumerate(bi): ai[j] -= bij def ddm_ineg(a): """a <-- -a""" for ai in a: for j, aij in enumerate(ai): ai[j] = -aij def ddm_imul(a, b): for ai in a: for j, aij in enumerate(ai): ai[j] = b * aij def ddm_imatmul(a, b, c): """a += b @ c""" cT = list(zip(*c)) for bi, ai in zip(b, a): for j, cTj in enumerate(cT): ai[j] = sum(map(mul, bi, cTj), ai[j]) def ddm_irref(a, _partial_pivot=False): """a <-- rref(a)""" # a is (m x n) m = len(a) if not m: return [] n = len(a[0]) i = 0 pivots = [] for j in range(n): # Proper pivoting should be used for all domains for performance # reasons but it is only strictly needed for RR and CC (and possibly # other domains like RR(x)). This path is used by DDM.rref() if the # domain is RR or CC. It uses partial (row) pivoting based on the # absolute value of the pivot candidates. if _partial_pivot: ip = max(range(i, m), key=lambda ip: abs(a[ip][j])) a[i], a[ip] = a[ip], a[i] # pivot aij = a[i][j] # zero-pivot if not aij: for ip in range(i+1, m): aij = a[ip][j] # row-swap if aij: a[i], a[ip] = a[ip], a[i] break else: # next column continue # normalise row ai = a[i] aijinv = aij**-1 for l in range(j, n): ai[l] *= aijinv # ai[j] = one # eliminate above and below to the right for k, ak in enumerate(a): if k == i or not ak[j]: continue akj = ak[j] ak[j] -= akj # ak[j] = zero for l in range(j+1, n): ak[l] -= akj * ai[l] # next row pivots.append(j) i += 1 # no more rows? if i >= m: break return pivots def ddm_idet(a, K): """a <-- echelon(a); return det""" # Bareiss algorithm # https://www.math.usm.edu/perry/Research/Thesis_DRL.pdf # a is (m x n) m = len(a) if not m: return K.one n = len(a[0]) exquo = K.exquo # uf keeps track of the sign change from row swaps uf = K.one for k in range(n-1): if not a[k][k]: for i in range(k+1, n): if a[i][k]: a[k], a[i] = a[i], a[k] uf = -uf break else: return K.zero akkm1 = a[k-1][k-1] if k else K.one for i in range(k+1, n): for j in range(k+1, n): a[i][j] = exquo(a[i][j]*a[k][k] - a[i][k]*a[k][j], akkm1) return uf * a[-1][-1] def ddm_iinv(ainv, a, K): if not K.is_Field: raise ValueError('Not a field') # a is (m x n) m = len(a) if not m: return n = len(a[0]) if m != n: raise NonSquareMatrixError eye = [[K.one if i==j else K.zero for j in range(n)] for i in range(n)] Aaug = [row + eyerow for row, eyerow in zip(a, eye)] pivots = ddm_irref(Aaug) if pivots != list(range(n)): raise NonInvertibleMatrixError('Matrix det == 0; not invertible.') ainv[:] = [row[n:] for row in Aaug] def ddm_ilu_split(L, U, K): """L, U <-- LU(U)""" m = len(U) if not m: return [] n = len(U[0]) swaps = ddm_ilu(U) zeros = [K.zero] * min(m, n) for i in range(1, m): j = min(i, n) L[i][:j] = U[i][:j] U[i][:j] = zeros[:j] return swaps def ddm_ilu(a): """a <-- LU(a)""" m = len(a) if not m: return [] n = len(a[0]) swaps = [] for i in range(min(m, n)): if not a[i][i]: for ip in range(i+1, m): if a[ip][i]: swaps.append((i, ip)) a[i], a[ip] = a[ip], a[i] break else: # M = Matrix([[1, 0, 0, 0], [0, 0, 0, 0], [0, 0, 1, 1], [0, 0, 1, 2]]) continue for j in range(i+1, m): l_ji = a[j][i] / a[i][i] a[j][i] = l_ji for k in range(i+1, n): a[j][k] -= l_ji * a[i][k] return swaps def ddm_ilu_solve(x, L, U, swaps, b): """x <-- solve(L*U*x = swaps(b))""" m = len(U) if not m: return n = len(U[0]) m2 = len(b) if not m2: raise DDMShapeError("Shape mismtch") o = len(b[0]) if m != m2: raise DDMShapeError("Shape mismtch") if m < n: raise NotImplementedError("Underdetermined") if swaps: b = [row[:] for row in b] for i1, i2 in swaps: b[i1], b[i2] = b[i2], b[i1] # solve Ly = b y = [[None] * o for _ in range(m)] for k in range(o): for i in range(m): rhs = b[i][k] for j in range(i): rhs -= L[i][j] * y[j][k] y[i][k] = rhs if m > n: for i in range(n, m): for j in range(o): if y[i][j]: raise NonInvertibleMatrixError # Solve Ux = y for k in range(o): for i in reversed(range(n)): if not U[i][i]: raise NonInvertibleMatrixError rhs = y[i][k] for j in range(i+1, n): rhs -= U[i][j] * x[j][k] x[i][k] = rhs / U[i][i] def ddm_berk(M, K): m = len(M) if not m: return [[K.one]] n = len(M[0]) if m != n: raise DDMShapeError("Not square") if n == 1: return [[K.one], [-M[0][0]]] a = M[0][0] R = [M[0][1:]] C = [[row[0]] for row in M[1:]] A = [row[1:] for row in M[1:]] q = ddm_berk(A, K) T = [[K.zero] * n for _ in range(n+1)] for i in range(n): T[i][i] = K.one T[i+1][i] = -a for i in range(2, n+1): if i == 2: AnC = C else: C = AnC AnC = [[K.zero] for row in C] ddm_imatmul(AnC, A, C) RAnC = [[K.zero]] ddm_imatmul(RAnC, R, AnC) for j in range(0, n+1-i): T[i+j][j] = -RAnC[0][0] qout = [[K.zero] for _ in range(n+1)] ddm_imatmul(qout, T, q) return qout
e3bc0db26ab342a5ca1b9ca8ef147bc3c1991f2fafa82597a9cf96e3a0e30985
""" Module for the DDM class. The DDM class is an internal representation used by DomainMatrix. The letters DDM stand for Dense Domain Matrix. A DDM instance represents a matrix using elements from a polynomial Domain (e.g. ZZ, QQ, ...) in a dense-matrix representation. Basic usage: >>> from sympy import ZZ, QQ >>> from sympy.polys.matrices.ddm import DDM >>> A = DDM([[ZZ(0), ZZ(1)], [ZZ(-1), ZZ(0)]], (2, 2), ZZ) >>> A.shape (2, 2) >>> A [[0, 1], [-1, 0]] >>> type(A) <class 'sympy.polys.matrices.ddm.DDM'> >>> A @ A [[-1, 0], [0, -1]] The ddm_* functions are designed to operate on DDM as well as on an ordinary list of lists: >>> from sympy.polys.matrices.dense import ddm_idet >>> ddm_idet(A, QQ) 1 >>> ddm_idet([[0, 1], [-1, 0]], QQ) 1 >>> A [[-1, 0], [0, -1]] Note that ddm_idet modifies the input matrix in-place. It is recommended to use the DDM.det method as a friendlier interface to this instead which takes care of copying the matrix: >>> B = DDM([[ZZ(0), ZZ(1)], [ZZ(-1), ZZ(0)]], (2, 2), ZZ) >>> B.det() 1 Normally DDM would not be used directly and is just part of the internal representation of DomainMatrix which adds further functionality including e.g. unifying domains. The dense format used by DDM is a list of lists of elements e.g. the 2x2 identity matrix is like [[1, 0], [0, 1]]. The DDM class itself is a subclass of list and its list items are plain lists. Elements are accessed as e.g. ddm[i][j] where ddm[i] gives the ith row and ddm[i][j] gets the element in the jth column of that row. Subclassing list makes e.g. iteration and indexing very efficient. We do not override __getitem__ because it would lose that benefit. The core routines are implemented by the ddm_* functions defined in dense.py. Those functions are intended to be able to operate on a raw list-of-lists representation of matrices with most functions operating in-place. The DDM class takes care of copying etc and also stores a Domain object associated with its elements. This makes it possible to implement things like A + B with domain checking and also shape checking so that the list of lists representation is friendlier. """ from .exceptions import DDMBadInputError, DDMShapeError, DDMDomainError from .dense import ( ddm_transpose, ddm_iadd, ddm_isub, ddm_ineg, ddm_imul, ddm_imatmul, ddm_irref, ddm_idet, ddm_iinv, ddm_ilu_split, ddm_ilu_solve, ddm_berk, ) class DDM(list): """Dense matrix based on polys domain elements This is a list subclass and is a wrapper for a list of lists that supports basic matrix arithmetic +, -, *, **. """ fmt = 'dense' def __init__(self, rowslist, shape, domain): super().__init__(rowslist) self.shape = self.rows, self.cols = m, n = shape self.domain = domain if not (len(self) == m and all(len(row) == n for row in self)): raise DDMBadInputError("Inconsistent row-list/shape") def getitem(self, i, j): return self[i][j] def extract_slice(self, slice1, slice2): ddm = [row[slice2] for row in self[slice1]] rows = len(ddm) cols = len(ddm[0]) if ddm else len(range(self.shape[1])[slice2]) return DDM(ddm, (rows, cols), self.domain) def to_list(self): return list(self) def to_ddm(self): return self def to_sdm(self): return SDM.from_list(self, self.shape, self.domain) def convert_to(self, K): Kold = self.domain if K == Kold: return self.copy() rows = ([K.convert_from(e, Kold) for e in row] for row in self) return DDM(rows, self.shape, K) def __str__(self): rowsstr = ['[%s]' % ', '.join(map(str, row)) for row in self] return '[%s]' % ', '.join(rowsstr) def __repr__(self): cls = type(self).__name__ rows = list.__repr__(self) return '%s(%s, %s, %s)' % (cls, rows, self.shape, self.domain) def __eq__(self, other): if not isinstance(other, DDM): return False return (super().__eq__(other) and self.domain == other.domain) def __ne__(self, other): return not self.__eq__(other) @classmethod def zeros(cls, shape, domain): z = domain.zero m, n = shape rowslist = ([z] * n for _ in range(m)) return DDM(rowslist, shape, domain) @classmethod def ones(cls, shape, domain): one = domain.one m, n = shape rowlist = ([one] * n for _ in range(m)) return DDM(rowlist, shape, domain) @classmethod def eye(cls, size, domain): one = domain.one ddm = cls.zeros((size, size), domain) for i in range(size): ddm[i][i] = one return ddm def copy(self): copyrows = (row[:] for row in self) return DDM(copyrows, self.shape, self.domain) def transpose(self): rows, cols = self.shape if rows: ddmT = ddm_transpose(self) else: ddmT = [[]] * cols return DDM(ddmT, (cols, rows), self.domain) def __add__(a, b): if not isinstance(b, DDM): return NotImplemented return a.add(b) def __sub__(a, b): if not isinstance(b, DDM): return NotImplemented return a.sub(b) def __neg__(a): return a.neg() def __mul__(a, b): if b in a.domain: return a.mul(b) else: return NotImplemented def __rmul__(a, b): if b in a.domain: return a.mul(b) else: return NotImplemented def __matmul__(a, b): if isinstance(b, DDM): return a.matmul(b) else: return NotImplemented @classmethod def _check(cls, a, op, b, ashape, bshape): if a.domain != b.domain: msg = "Domain mismatch: %s %s %s" % (a.domain, op, b.domain) raise DDMDomainError(msg) if ashape != bshape: msg = "Shape mismatch: %s %s %s" % (a.shape, op, b.shape) raise DDMShapeError(msg) def add(a, b): """a + b""" a._check(a, '+', b, a.shape, b.shape) c = a.copy() ddm_iadd(c, b) return c def sub(a, b): """a - b""" a._check(a, '-', b, a.shape, b.shape) c = a.copy() ddm_isub(c, b) return c def neg(a): """-a""" b = a.copy() ddm_ineg(b) return b def mul(a, b): c = a.copy() ddm_imul(c, b) return c def matmul(a, b): """a @ b (matrix product)""" m, o = a.shape o2, n = b.shape a._check(a, '*', b, o, o2) c = a.zeros((m, n), a.domain) ddm_imatmul(c, a, b) return c def hstack(A, B): Anew = list(A.copy()) rows, cols = A.shape domain = A.domain Brows, Bcols = B.shape assert Brows == rows assert B.domain == domain cols += Bcols for i, Bi in enumerate(B): Anew[i].extend(Bi) return DDM(Anew, (rows, cols), A.domain) def vstack(A, B): Anew = list(A.copy()) rows, cols = A.shape domain = A.domain Brows, Bcols = B.shape assert Bcols == cols assert B.domain == domain rows += Brows Anew.extend(B.copy()) return DDM(Anew, (rows, cols), A.domain) def applyfunc(self, func, domain): elements = (list(map(func, row)) for row in self) return DDM(elements, self.shape, domain) def rref(a): """Reduced-row echelon form of a and list of pivots""" b = a.copy() K = a.domain partial_pivot = K.is_RealField or K.is_ComplexField pivots = ddm_irref(b, _partial_pivot=partial_pivot) return b, pivots def nullspace(a): rref, pivots = a.rref() rows, cols = a.shape domain = a.domain basis = [] nonpivots = [] for i in range(cols): if i in pivots: continue nonpivots.append(i) vec = [domain.one if i == j else domain.zero for j in range(cols)] for ii, jj in enumerate(pivots): vec[jj] -= rref[ii][i] basis.append(vec) return DDM(basis, (len(basis), cols), domain), nonpivots def particular(a): return a.to_sdm().particular().to_ddm() def det(a): """Determinant of a""" m, n = a.shape if m != n: raise DDMShapeError("Determinant of non-square matrix") b = a.copy() K = b.domain deta = ddm_idet(b, K) return deta def inv(a): """Inverse of a""" m, n = a.shape if m != n: raise DDMShapeError("Determinant of non-square matrix") ainv = a.copy() K = a.domain ddm_iinv(ainv, a, K) return ainv def lu(a): """L, U decomposition of a""" m, n = a.shape K = a.domain U = a.copy() L = a.eye(m, K) swaps = ddm_ilu_split(L, U, K) return L, U, swaps def lu_solve(a, b): """x where a*x = b""" m, n = a.shape m2, o = b.shape a._check(a, 'lu_solve', b, m, m2) L, U, swaps = a.lu() x = a.zeros((n, o), a.domain) ddm_ilu_solve(x, L, U, swaps, b) return x def charpoly(a): """Coefficients of characteristic polynomial of a""" K = a.domain m, n = a.shape if m != n: raise DDMShapeError("Charpoly of non-square matrix") vec = ddm_berk(a, K) coeffs = [vec[i][0] for i in range(n+1)] return coeffs from .sdm import SDM
b977171f3a4e5705a6dd87e4e6b77e468d4298aaa26f3484849749ee5d05f48f
"""Tests for classes defining properties of ground domains, e.g. ZZ, QQ, ZZ[x] ... """ from sympy import I, S, sqrt, sin, oo, Poly, Float, Integer, Rational, pi from sympy.abc import x, y, z from sympy.utilities.iterables import cartes from sympy.core.compatibility import HAS_GMPY from sympy.polys.domains import (ZZ, QQ, RR, CC, FF, GF, EX, ZZ_gmpy, ZZ_python, QQ_gmpy, QQ_python) from sympy.polys.domains.algebraicfield import AlgebraicField from sympy.polys.domains.gaussiandomains import ZZ_I, QQ_I from sympy.polys.domains.polynomialring import PolynomialRing from sympy.polys.domains.realfield import RealField from sympy.polys.rings import ring from sympy.polys.fields import field from sympy.polys.agca.extensions import FiniteExtension from sympy.polys.polyerrors import ( UnificationFailed, GeneratorsError, CoercionFailed, NotInvertible, DomainError) from sympy.polys.polyutils import illegal from sympy.testing.pytest import raises ALG = QQ.algebraic_field(sqrt(2), sqrt(3)) def unify(K0, K1): return K0.unify(K1) def test_Domain_unify(): F3 = GF(3) assert unify(F3, F3) == F3 assert unify(F3, ZZ) == ZZ assert unify(F3, QQ) == QQ assert unify(F3, ALG) == ALG assert unify(F3, RR) == RR assert unify(F3, CC) == CC assert unify(F3, ZZ[x]) == ZZ[x] assert unify(F3, ZZ.frac_field(x)) == ZZ.frac_field(x) assert unify(F3, EX) == EX assert unify(ZZ, F3) == ZZ assert unify(ZZ, ZZ) == ZZ assert unify(ZZ, QQ) == QQ assert unify(ZZ, ALG) == ALG assert unify(ZZ, RR) == RR assert unify(ZZ, CC) == CC assert unify(ZZ, ZZ[x]) == ZZ[x] assert unify(ZZ, ZZ.frac_field(x)) == ZZ.frac_field(x) assert unify(ZZ, EX) == EX assert unify(QQ, F3) == QQ assert unify(QQ, ZZ) == QQ assert unify(QQ, QQ) == QQ assert unify(QQ, ALG) == ALG assert unify(QQ, RR) == RR assert unify(QQ, CC) == CC assert unify(QQ, ZZ[x]) == QQ[x] assert unify(QQ, ZZ.frac_field(x)) == QQ.frac_field(x) assert unify(QQ, EX) == EX assert unify(ZZ_I, F3) == ZZ_I assert unify(ZZ_I, ZZ) == ZZ_I assert unify(ZZ_I, ZZ_I) == ZZ_I assert unify(ZZ_I, QQ) == QQ_I assert unify(ZZ_I, ALG) == QQ.algebraic_field(I, sqrt(2), sqrt(3)) assert unify(ZZ_I, RR) == CC assert unify(ZZ_I, CC) == CC assert unify(ZZ_I, ZZ[x]) == ZZ_I[x] assert unify(ZZ_I, ZZ_I[x]) == ZZ_I[x] assert unify(ZZ_I, ZZ.frac_field(x)) == ZZ_I.frac_field(x) assert unify(ZZ_I, ZZ_I.frac_field(x)) == ZZ_I.frac_field(x) assert unify(ZZ_I, EX) == EX assert unify(QQ_I, F3) == QQ_I assert unify(QQ_I, ZZ) == QQ_I assert unify(QQ_I, ZZ_I) == QQ_I assert unify(QQ_I, QQ) == QQ_I assert unify(QQ_I, ALG) == QQ.algebraic_field(I, sqrt(2), sqrt(3)) assert unify(QQ_I, RR) == CC assert unify(QQ_I, CC) == CC assert unify(QQ_I, ZZ[x]) == QQ_I[x] assert unify(QQ_I, ZZ_I[x]) == QQ_I[x] assert unify(QQ_I, QQ[x]) == QQ_I[x] assert unify(QQ_I, QQ_I[x]) == QQ_I[x] assert unify(QQ_I, ZZ.frac_field(x)) == QQ_I.frac_field(x) assert unify(QQ_I, ZZ_I.frac_field(x)) == QQ_I.frac_field(x) assert unify(QQ_I, QQ.frac_field(x)) == QQ_I.frac_field(x) assert unify(QQ_I, QQ_I.frac_field(x)) == QQ_I.frac_field(x) assert unify(QQ_I, EX) == EX assert unify(RR, F3) == RR assert unify(RR, ZZ) == RR assert unify(RR, QQ) == RR assert unify(RR, ALG) == RR assert unify(RR, RR) == RR assert unify(RR, CC) == CC assert unify(RR, ZZ[x]) == RR[x] assert unify(RR, ZZ.frac_field(x)) == RR.frac_field(x) assert unify(RR, EX) == EX assert RR[x].unify(ZZ.frac_field(y)) == RR.frac_field(x, y) assert unify(CC, F3) == CC assert unify(CC, ZZ) == CC assert unify(CC, QQ) == CC assert unify(CC, ALG) == CC assert unify(CC, RR) == CC assert unify(CC, CC) == CC assert unify(CC, ZZ[x]) == CC[x] assert unify(CC, ZZ.frac_field(x)) == CC.frac_field(x) assert unify(CC, EX) == EX assert unify(ZZ[x], F3) == ZZ[x] assert unify(ZZ[x], ZZ) == ZZ[x] assert unify(ZZ[x], QQ) == QQ[x] assert unify(ZZ[x], ALG) == ALG[x] assert unify(ZZ[x], RR) == RR[x] assert unify(ZZ[x], CC) == CC[x] assert unify(ZZ[x], ZZ[x]) == ZZ[x] assert unify(ZZ[x], ZZ.frac_field(x)) == ZZ.frac_field(x) assert unify(ZZ[x], EX) == EX assert unify(ZZ.frac_field(x), F3) == ZZ.frac_field(x) assert unify(ZZ.frac_field(x), ZZ) == ZZ.frac_field(x) assert unify(ZZ.frac_field(x), QQ) == QQ.frac_field(x) assert unify(ZZ.frac_field(x), ALG) == ALG.frac_field(x) assert unify(ZZ.frac_field(x), RR) == RR.frac_field(x) assert unify(ZZ.frac_field(x), CC) == CC.frac_field(x) assert unify(ZZ.frac_field(x), ZZ[x]) == ZZ.frac_field(x) assert unify(ZZ.frac_field(x), ZZ.frac_field(x)) == ZZ.frac_field(x) assert unify(ZZ.frac_field(x), EX) == EX assert unify(EX, F3) == EX assert unify(EX, ZZ) == EX assert unify(EX, QQ) == EX assert unify(EX, ALG) == EX assert unify(EX, RR) == EX assert unify(EX, CC) == EX assert unify(EX, ZZ[x]) == EX assert unify(EX, ZZ.frac_field(x)) == EX assert unify(EX, EX) == EX def test_Domain_unify_composite(): assert unify(ZZ.poly_ring(x), ZZ) == ZZ.poly_ring(x) assert unify(ZZ.poly_ring(x), QQ) == QQ.poly_ring(x) assert unify(QQ.poly_ring(x), ZZ) == QQ.poly_ring(x) assert unify(QQ.poly_ring(x), QQ) == QQ.poly_ring(x) assert unify(ZZ, ZZ.poly_ring(x)) == ZZ.poly_ring(x) assert unify(QQ, ZZ.poly_ring(x)) == QQ.poly_ring(x) assert unify(ZZ, QQ.poly_ring(x)) == QQ.poly_ring(x) assert unify(QQ, QQ.poly_ring(x)) == QQ.poly_ring(x) assert unify(ZZ.poly_ring(x, y), ZZ) == ZZ.poly_ring(x, y) assert unify(ZZ.poly_ring(x, y), QQ) == QQ.poly_ring(x, y) assert unify(QQ.poly_ring(x, y), ZZ) == QQ.poly_ring(x, y) assert unify(QQ.poly_ring(x, y), QQ) == QQ.poly_ring(x, y) assert unify(ZZ, ZZ.poly_ring(x, y)) == ZZ.poly_ring(x, y) assert unify(QQ, ZZ.poly_ring(x, y)) == QQ.poly_ring(x, y) assert unify(ZZ, QQ.poly_ring(x, y)) == QQ.poly_ring(x, y) assert unify(QQ, QQ.poly_ring(x, y)) == QQ.poly_ring(x, y) assert unify(ZZ.frac_field(x), ZZ) == ZZ.frac_field(x) assert unify(ZZ.frac_field(x), QQ) == QQ.frac_field(x) assert unify(QQ.frac_field(x), ZZ) == QQ.frac_field(x) assert unify(QQ.frac_field(x), QQ) == QQ.frac_field(x) assert unify(ZZ, ZZ.frac_field(x)) == ZZ.frac_field(x) assert unify(QQ, ZZ.frac_field(x)) == QQ.frac_field(x) assert unify(ZZ, QQ.frac_field(x)) == QQ.frac_field(x) assert unify(QQ, QQ.frac_field(x)) == QQ.frac_field(x) assert unify(ZZ.frac_field(x, y), ZZ) == ZZ.frac_field(x, y) assert unify(ZZ.frac_field(x, y), QQ) == QQ.frac_field(x, y) assert unify(QQ.frac_field(x, y), ZZ) == QQ.frac_field(x, y) assert unify(QQ.frac_field(x, y), QQ) == QQ.frac_field(x, y) assert unify(ZZ, ZZ.frac_field(x, y)) == ZZ.frac_field(x, y) assert unify(QQ, ZZ.frac_field(x, y)) == QQ.frac_field(x, y) assert unify(ZZ, QQ.frac_field(x, y)) == QQ.frac_field(x, y) assert unify(QQ, QQ.frac_field(x, y)) == QQ.frac_field(x, y) assert unify(ZZ.poly_ring(x), ZZ.poly_ring(x)) == ZZ.poly_ring(x) assert unify(ZZ.poly_ring(x), QQ.poly_ring(x)) == QQ.poly_ring(x) assert unify(QQ.poly_ring(x), ZZ.poly_ring(x)) == QQ.poly_ring(x) assert unify(QQ.poly_ring(x), QQ.poly_ring(x)) == QQ.poly_ring(x) assert unify(ZZ.poly_ring(x, y), ZZ.poly_ring(x)) == ZZ.poly_ring(x, y) assert unify(ZZ.poly_ring(x, y), QQ.poly_ring(x)) == QQ.poly_ring(x, y) assert unify(QQ.poly_ring(x, y), ZZ.poly_ring(x)) == QQ.poly_ring(x, y) assert unify(QQ.poly_ring(x, y), QQ.poly_ring(x)) == QQ.poly_ring(x, y) assert unify(ZZ.poly_ring(x), ZZ.poly_ring(x, y)) == ZZ.poly_ring(x, y) assert unify(ZZ.poly_ring(x), QQ.poly_ring(x, y)) == QQ.poly_ring(x, y) assert unify(QQ.poly_ring(x), ZZ.poly_ring(x, y)) == QQ.poly_ring(x, y) assert unify(QQ.poly_ring(x), QQ.poly_ring(x, y)) == QQ.poly_ring(x, y) assert unify(ZZ.poly_ring(x, y), ZZ.poly_ring(x, z)) == ZZ.poly_ring(x, y, z) assert unify(ZZ.poly_ring(x, y), QQ.poly_ring(x, z)) == QQ.poly_ring(x, y, z) assert unify(QQ.poly_ring(x, y), ZZ.poly_ring(x, z)) == QQ.poly_ring(x, y, z) assert unify(QQ.poly_ring(x, y), QQ.poly_ring(x, z)) == QQ.poly_ring(x, y, z) assert unify(ZZ.frac_field(x), ZZ.frac_field(x)) == ZZ.frac_field(x) assert unify(ZZ.frac_field(x), QQ.frac_field(x)) == QQ.frac_field(x) assert unify(QQ.frac_field(x), ZZ.frac_field(x)) == QQ.frac_field(x) assert unify(QQ.frac_field(x), QQ.frac_field(x)) == QQ.frac_field(x) assert unify(ZZ.frac_field(x, y), ZZ.frac_field(x)) == ZZ.frac_field(x, y) assert unify(ZZ.frac_field(x, y), QQ.frac_field(x)) == QQ.frac_field(x, y) assert unify(QQ.frac_field(x, y), ZZ.frac_field(x)) == QQ.frac_field(x, y) assert unify(QQ.frac_field(x, y), QQ.frac_field(x)) == QQ.frac_field(x, y) assert unify(ZZ.frac_field(x), ZZ.frac_field(x, y)) == ZZ.frac_field(x, y) assert unify(ZZ.frac_field(x), QQ.frac_field(x, y)) == QQ.frac_field(x, y) assert unify(QQ.frac_field(x), ZZ.frac_field(x, y)) == QQ.frac_field(x, y) assert unify(QQ.frac_field(x), QQ.frac_field(x, y)) == QQ.frac_field(x, y) assert unify(ZZ.frac_field(x, y), ZZ.frac_field(x, z)) == ZZ.frac_field(x, y, z) assert unify(ZZ.frac_field(x, y), QQ.frac_field(x, z)) == QQ.frac_field(x, y, z) assert unify(QQ.frac_field(x, y), ZZ.frac_field(x, z)) == QQ.frac_field(x, y, z) assert unify(QQ.frac_field(x, y), QQ.frac_field(x, z)) == QQ.frac_field(x, y, z) assert unify(ZZ.poly_ring(x), ZZ.frac_field(x)) == ZZ.frac_field(x) assert unify(ZZ.poly_ring(x), QQ.frac_field(x)) == ZZ.frac_field(x) assert unify(QQ.poly_ring(x), ZZ.frac_field(x)) == ZZ.frac_field(x) assert unify(QQ.poly_ring(x), QQ.frac_field(x)) == QQ.frac_field(x) assert unify(ZZ.poly_ring(x, y), ZZ.frac_field(x)) == ZZ.frac_field(x, y) assert unify(ZZ.poly_ring(x, y), QQ.frac_field(x)) == ZZ.frac_field(x, y) assert unify(QQ.poly_ring(x, y), ZZ.frac_field(x)) == ZZ.frac_field(x, y) assert unify(QQ.poly_ring(x, y), QQ.frac_field(x)) == QQ.frac_field(x, y) assert unify(ZZ.poly_ring(x), ZZ.frac_field(x, y)) == ZZ.frac_field(x, y) assert unify(ZZ.poly_ring(x), QQ.frac_field(x, y)) == ZZ.frac_field(x, y) assert unify(QQ.poly_ring(x), ZZ.frac_field(x, y)) == ZZ.frac_field(x, y) assert unify(QQ.poly_ring(x), QQ.frac_field(x, y)) == QQ.frac_field(x, y) assert unify(ZZ.poly_ring(x, y), ZZ.frac_field(x, z)) == ZZ.frac_field(x, y, z) assert unify(ZZ.poly_ring(x, y), QQ.frac_field(x, z)) == ZZ.frac_field(x, y, z) assert unify(QQ.poly_ring(x, y), ZZ.frac_field(x, z)) == ZZ.frac_field(x, y, z) assert unify(QQ.poly_ring(x, y), QQ.frac_field(x, z)) == QQ.frac_field(x, y, z) assert unify(ZZ.frac_field(x), ZZ.poly_ring(x)) == ZZ.frac_field(x) assert unify(ZZ.frac_field(x), QQ.poly_ring(x)) == ZZ.frac_field(x) assert unify(QQ.frac_field(x), ZZ.poly_ring(x)) == ZZ.frac_field(x) assert unify(QQ.frac_field(x), QQ.poly_ring(x)) == QQ.frac_field(x) assert unify(ZZ.frac_field(x, y), ZZ.poly_ring(x)) == ZZ.frac_field(x, y) assert unify(ZZ.frac_field(x, y), QQ.poly_ring(x)) == ZZ.frac_field(x, y) assert unify(QQ.frac_field(x, y), ZZ.poly_ring(x)) == ZZ.frac_field(x, y) assert unify(QQ.frac_field(x, y), QQ.poly_ring(x)) == QQ.frac_field(x, y) assert unify(ZZ.frac_field(x), ZZ.poly_ring(x, y)) == ZZ.frac_field(x, y) assert unify(ZZ.frac_field(x), QQ.poly_ring(x, y)) == ZZ.frac_field(x, y) assert unify(QQ.frac_field(x), ZZ.poly_ring(x, y)) == ZZ.frac_field(x, y) assert unify(QQ.frac_field(x), QQ.poly_ring(x, y)) == QQ.frac_field(x, y) assert unify(ZZ.frac_field(x, y), ZZ.poly_ring(x, z)) == ZZ.frac_field(x, y, z) assert unify(ZZ.frac_field(x, y), QQ.poly_ring(x, z)) == ZZ.frac_field(x, y, z) assert unify(QQ.frac_field(x, y), ZZ.poly_ring(x, z)) == ZZ.frac_field(x, y, z) assert unify(QQ.frac_field(x, y), QQ.poly_ring(x, z)) == QQ.frac_field(x, y, z) def test_Domain_unify_algebraic(): sqrt5 = QQ.algebraic_field(sqrt(5)) sqrt7 = QQ.algebraic_field(sqrt(7)) sqrt57 = QQ.algebraic_field(sqrt(5), sqrt(7)) assert sqrt5.unify(sqrt7) == sqrt57 assert sqrt5.unify(sqrt5[x, y]) == sqrt5[x, y] assert sqrt5[x, y].unify(sqrt5) == sqrt5[x, y] assert sqrt5.unify(sqrt5.frac_field(x, y)) == sqrt5.frac_field(x, y) assert sqrt5.frac_field(x, y).unify(sqrt5) == sqrt5.frac_field(x, y) assert sqrt5.unify(sqrt7[x, y]) == sqrt57[x, y] assert sqrt5[x, y].unify(sqrt7) == sqrt57[x, y] assert sqrt5.unify(sqrt7.frac_field(x, y)) == sqrt57.frac_field(x, y) assert sqrt5.frac_field(x, y).unify(sqrt7) == sqrt57.frac_field(x, y) def test_Domain_unify_FiniteExtension(): KxZZ = FiniteExtension(Poly(x**2 - 2, x, domain=ZZ)) KxQQ = FiniteExtension(Poly(x**2 - 2, x, domain=QQ)) KxZZy = FiniteExtension(Poly(x**2 - 2, x, domain=ZZ[y])) KxQQy = FiniteExtension(Poly(x**2 - 2, x, domain=QQ[y])) assert KxZZ.unify(KxZZ) == KxZZ assert KxQQ.unify(KxQQ) == KxQQ assert KxZZy.unify(KxZZy) == KxZZy assert KxQQy.unify(KxQQy) == KxQQy assert KxZZ.unify(ZZ) == KxZZ assert KxZZ.unify(QQ) == KxQQ assert KxQQ.unify(ZZ) == KxQQ assert KxQQ.unify(QQ) == KxQQ assert KxZZ.unify(ZZ[y]) == KxZZy assert KxZZ.unify(QQ[y]) == KxQQy assert KxQQ.unify(ZZ[y]) == KxQQy assert KxQQ.unify(QQ[y]) == KxQQy assert KxZZy.unify(ZZ) == KxZZy assert KxZZy.unify(QQ) == KxQQy assert KxQQy.unify(ZZ) == KxQQy assert KxQQy.unify(QQ) == KxQQy assert KxZZy.unify(ZZ[y]) == KxZZy assert KxZZy.unify(QQ[y]) == KxQQy assert KxQQy.unify(ZZ[y]) == KxQQy assert KxQQy.unify(QQ[y]) == KxQQy K = FiniteExtension(Poly(x**2 - 2, x, domain=ZZ[y])) assert K.unify(ZZ) == K assert K.unify(ZZ[x]) == K assert K.unify(ZZ[y]) == K assert K.unify(ZZ[x, y]) == K Kz = FiniteExtension(Poly(x**2 - 2, x, domain=ZZ[y, z])) assert K.unify(ZZ[z]) == Kz assert K.unify(ZZ[x, z]) == Kz assert K.unify(ZZ[y, z]) == Kz assert K.unify(ZZ[x, y, z]) == Kz Kx = FiniteExtension(Poly(x**2 - 2, x, domain=ZZ)) Ky = FiniteExtension(Poly(y**2 - 2, y, domain=ZZ)) Kxy = FiniteExtension(Poly(y**2 - 2, y, domain=Kx)) assert Kx.unify(Kx) == Kx assert Ky.unify(Ky) == Ky assert Kx.unify(Ky) == Kxy assert Ky.unify(Kx) == Kxy def test_Domain_unify_with_symbols(): raises(UnificationFailed, lambda: ZZ[x, y].unify_with_symbols(ZZ, (y, z))) raises(UnificationFailed, lambda: ZZ.unify_with_symbols(ZZ[x, y], (y, z))) def test_Domain__contains__(): assert (0 in EX) is True assert (0 in ZZ) is True assert (0 in QQ) is True assert (0 in RR) is True assert (0 in CC) is True assert (0 in ALG) is True assert (0 in ZZ[x, y]) is True assert (0 in QQ[x, y]) is True assert (0 in RR[x, y]) is True assert (-7 in EX) is True assert (-7 in ZZ) is True assert (-7 in QQ) is True assert (-7 in RR) is True assert (-7 in CC) is True assert (-7 in ALG) is True assert (-7 in ZZ[x, y]) is True assert (-7 in QQ[x, y]) is True assert (-7 in RR[x, y]) is True assert (17 in EX) is True assert (17 in ZZ) is True assert (17 in QQ) is True assert (17 in RR) is True assert (17 in CC) is True assert (17 in ALG) is True assert (17 in ZZ[x, y]) is True assert (17 in QQ[x, y]) is True assert (17 in RR[x, y]) is True assert (Rational(-1, 7) in EX) is True assert (Rational(-1, 7) in ZZ) is False assert (Rational(-1, 7) in QQ) is True assert (Rational(-1, 7) in RR) is True assert (Rational(-1, 7) in CC) is True assert (Rational(-1, 7) in ALG) is True assert (Rational(-1, 7) in ZZ[x, y]) is False assert (Rational(-1, 7) in QQ[x, y]) is True assert (Rational(-1, 7) in RR[x, y]) is True assert (Rational(3, 5) in EX) is True assert (Rational(3, 5) in ZZ) is False assert (Rational(3, 5) in QQ) is True assert (Rational(3, 5) in RR) is True assert (Rational(3, 5) in CC) is True assert (Rational(3, 5) in ALG) is True assert (Rational(3, 5) in ZZ[x, y]) is False assert (Rational(3, 5) in QQ[x, y]) is True assert (Rational(3, 5) in RR[x, y]) is True assert (3.0 in EX) is True assert (3.0 in ZZ) is True assert (3.0 in QQ) is True assert (3.0 in RR) is True assert (3.0 in CC) is True assert (3.0 in ALG) is True assert (3.0 in ZZ[x, y]) is True assert (3.0 in QQ[x, y]) is True assert (3.0 in RR[x, y]) is True assert (3.14 in EX) is True assert (3.14 in ZZ) is False assert (3.14 in QQ) is True assert (3.14 in RR) is True assert (3.14 in CC) is True assert (3.14 in ALG) is True assert (3.14 in ZZ[x, y]) is False assert (3.14 in QQ[x, y]) is True assert (3.14 in RR[x, y]) is True assert (oo in ALG) is False assert (oo in ZZ[x, y]) is False assert (oo in QQ[x, y]) is False assert (-oo in ZZ) is False assert (-oo in QQ) is False assert (-oo in ALG) is False assert (-oo in ZZ[x, y]) is False assert (-oo in QQ[x, y]) is False assert (sqrt(7) in EX) is True assert (sqrt(7) in ZZ) is False assert (sqrt(7) in QQ) is False assert (sqrt(7) in RR) is True assert (sqrt(7) in CC) is True assert (sqrt(7) in ALG) is False assert (sqrt(7) in ZZ[x, y]) is False assert (sqrt(7) in QQ[x, y]) is False assert (sqrt(7) in RR[x, y]) is True assert (2*sqrt(3) + 1 in EX) is True assert (2*sqrt(3) + 1 in ZZ) is False assert (2*sqrt(3) + 1 in QQ) is False assert (2*sqrt(3) + 1 in RR) is True assert (2*sqrt(3) + 1 in CC) is True assert (2*sqrt(3) + 1 in ALG) is True assert (2*sqrt(3) + 1 in ZZ[x, y]) is False assert (2*sqrt(3) + 1 in QQ[x, y]) is False assert (2*sqrt(3) + 1 in RR[x, y]) is True assert (sin(1) in EX) is True assert (sin(1) in ZZ) is False assert (sin(1) in QQ) is False assert (sin(1) in RR) is True assert (sin(1) in CC) is True assert (sin(1) in ALG) is False assert (sin(1) in ZZ[x, y]) is False assert (sin(1) in QQ[x, y]) is False assert (sin(1) in RR[x, y]) is True assert (x**2 + 1 in EX) is True assert (x**2 + 1 in ZZ) is False assert (x**2 + 1 in QQ) is False assert (x**2 + 1 in RR) is False assert (x**2 + 1 in CC) is False assert (x**2 + 1 in ALG) is False assert (x**2 + 1 in ZZ[x]) is True assert (x**2 + 1 in QQ[x]) is True assert (x**2 + 1 in RR[x]) is True assert (x**2 + 1 in ZZ[x, y]) is True assert (x**2 + 1 in QQ[x, y]) is True assert (x**2 + 1 in RR[x, y]) is True assert (x**2 + y**2 in EX) is True assert (x**2 + y**2 in ZZ) is False assert (x**2 + y**2 in QQ) is False assert (x**2 + y**2 in RR) is False assert (x**2 + y**2 in CC) is False assert (x**2 + y**2 in ALG) is False assert (x**2 + y**2 in ZZ[x]) is False assert (x**2 + y**2 in QQ[x]) is False assert (x**2 + y**2 in RR[x]) is False assert (x**2 + y**2 in ZZ[x, y]) is True assert (x**2 + y**2 in QQ[x, y]) is True assert (x**2 + y**2 in RR[x, y]) is True assert (Rational(3, 2)*x/(y + 1) - z in QQ[x, y, z]) is False def test_Domain_get_ring(): assert ZZ.has_assoc_Ring is True assert QQ.has_assoc_Ring is True assert ZZ[x].has_assoc_Ring is True assert QQ[x].has_assoc_Ring is True assert ZZ[x, y].has_assoc_Ring is True assert QQ[x, y].has_assoc_Ring is True assert ZZ.frac_field(x).has_assoc_Ring is True assert QQ.frac_field(x).has_assoc_Ring is True assert ZZ.frac_field(x, y).has_assoc_Ring is True assert QQ.frac_field(x, y).has_assoc_Ring is True assert EX.has_assoc_Ring is False assert RR.has_assoc_Ring is False assert ALG.has_assoc_Ring is False assert ZZ.get_ring() == ZZ assert QQ.get_ring() == ZZ assert ZZ[x].get_ring() == ZZ[x] assert QQ[x].get_ring() == QQ[x] assert ZZ[x, y].get_ring() == ZZ[x, y] assert QQ[x, y].get_ring() == QQ[x, y] assert ZZ.frac_field(x).get_ring() == ZZ[x] assert QQ.frac_field(x).get_ring() == QQ[x] assert ZZ.frac_field(x, y).get_ring() == ZZ[x, y] assert QQ.frac_field(x, y).get_ring() == QQ[x, y] assert EX.get_ring() == EX assert RR.get_ring() == RR # XXX: This should also be like RR raises(DomainError, lambda: ALG.get_ring()) def test_Domain_get_field(): assert EX.has_assoc_Field is True assert ZZ.has_assoc_Field is True assert QQ.has_assoc_Field is True assert RR.has_assoc_Field is True assert ALG.has_assoc_Field is True assert ZZ[x].has_assoc_Field is True assert QQ[x].has_assoc_Field is True assert ZZ[x, y].has_assoc_Field is True assert QQ[x, y].has_assoc_Field is True assert EX.get_field() == EX assert ZZ.get_field() == QQ assert QQ.get_field() == QQ assert RR.get_field() == RR assert ALG.get_field() == ALG assert ZZ[x].get_field() == ZZ.frac_field(x) assert QQ[x].get_field() == QQ.frac_field(x) assert ZZ[x, y].get_field() == ZZ.frac_field(x, y) assert QQ[x, y].get_field() == QQ.frac_field(x, y) def test_Domain_get_exact(): assert EX.get_exact() == EX assert ZZ.get_exact() == ZZ assert QQ.get_exact() == QQ assert RR.get_exact() == QQ assert ALG.get_exact() == ALG assert ZZ[x].get_exact() == ZZ[x] assert QQ[x].get_exact() == QQ[x] assert ZZ[x, y].get_exact() == ZZ[x, y] assert QQ[x, y].get_exact() == QQ[x, y] assert ZZ.frac_field(x).get_exact() == ZZ.frac_field(x) assert QQ.frac_field(x).get_exact() == QQ.frac_field(x) assert ZZ.frac_field(x, y).get_exact() == ZZ.frac_field(x, y) assert QQ.frac_field(x, y).get_exact() == QQ.frac_field(x, y) def test_Domain_is_unit(): nums = [-2, -1, 0, 1, 2] invring = [False, True, False, True, False] invfield = [True, True, False, True, True] ZZx, QQx, QQxf = ZZ[x], QQ[x], QQ.frac_field(x) assert [ZZ.is_unit(ZZ(n)) for n in nums] == invring assert [QQ.is_unit(QQ(n)) for n in nums] == invfield assert [ZZx.is_unit(ZZx(n)) for n in nums] == invring assert [QQx.is_unit(QQx(n)) for n in nums] == invfield assert [QQxf.is_unit(QQxf(n)) for n in nums] == invfield assert ZZx.is_unit(ZZx(x)) is False assert QQx.is_unit(QQx(x)) is False assert QQxf.is_unit(QQxf(x)) is True def test_Domain_convert(): def check_element(e1, e2, K1, K2, K3): assert type(e1) is type(e2), '%s, %s: %s %s -> %s' % (e1, e2, K1, K2, K3) assert e1 == e2, '%s, %s: %s %s -> %s' % (e1, e2, K1, K2, K3) def check_domains(K1, K2): K3 = K1.unify(K2) check_element(K3.convert_from(K1.one, K1), K3.one , K1, K2, K3) check_element(K3.convert_from(K2.one, K2), K3.one , K1, K2, K3) check_element(K3.convert_from(K1.zero, K1), K3.zero, K1, K2, K3) check_element(K3.convert_from(K2.zero, K2), K3.zero, K1, K2, K3) def composite_domains(K): domains = [ K, K[y], K[z], K[y, z], K.frac_field(y), K.frac_field(z), K.frac_field(y, z), # XXX: These should be tested and made to work... # K.old_poly_ring(y), K.old_frac_field(y), ] return domains QQ2 = QQ.algebraic_field(sqrt(2)) QQ3 = QQ.algebraic_field(sqrt(3)) doms = [ZZ, QQ, QQ2, QQ3, QQ_I, ZZ_I, RR, CC] for i, K1 in enumerate(doms): for K2 in doms[i:]: for K3 in composite_domains(K1): for K4 in composite_domains(K2): check_domains(K3, K4) assert QQ.convert(10e-52) == QQ(1684996666696915, 1684996666696914987166688442938726917102321526408785780068975640576) R, xr = ring("x", ZZ) assert ZZ.convert(xr - xr) == 0 assert ZZ.convert(xr - xr, R.to_domain()) == 0 assert CC.convert(ZZ_I(1, 2)) == CC(1, 2) assert CC.convert(QQ_I(1, 2)) == CC(1, 2) K1 = QQ.frac_field(x) K2 = ZZ.frac_field(x) K3 = QQ[x] K4 = ZZ[x] Ks = [K1, K2, K3, K4] for Ka, Kb in cartes(Ks, Ks): assert Ka.convert_from(Kb.from_sympy(x), Kb) == Ka.from_sympy(x) assert K2.convert_from(QQ(1, 2), QQ) == K2(QQ(1, 2)) def test_GlobalPolynomialRing_convert(): K1 = QQ.old_poly_ring(x) K2 = QQ[x] assert K1.convert(x) == K1.convert(K2.convert(x), K2) assert K2.convert(x) == K2.convert(K1.convert(x), K1) K1 = QQ.old_poly_ring(x, y) K2 = QQ[x] assert K1.convert(x) == K1.convert(K2.convert(x), K2) #assert K2.convert(x) == K2.convert(K1.convert(x), K1) K1 = ZZ.old_poly_ring(x, y) K2 = QQ[x] assert K1.convert(x) == K1.convert(K2.convert(x), K2) #assert K2.convert(x) == K2.convert(K1.convert(x), K1) def test_PolynomialRing__init(): R, = ring("", ZZ) assert ZZ.poly_ring() == R.to_domain() def test_FractionField__init(): F, = field("", ZZ) assert ZZ.frac_field() == F.to_domain() def test_FractionField_convert(): K = QQ.frac_field(x) assert K.convert(QQ(2, 3), QQ) == K.from_sympy(Rational(2, 3)) K = QQ.frac_field(x) assert K.convert(ZZ(2), ZZ) == K.from_sympy(Integer(2)) def test_inject(): assert ZZ.inject(x, y, z) == ZZ[x, y, z] assert ZZ[x].inject(y, z) == ZZ[x, y, z] assert ZZ.frac_field(x).inject(y, z) == ZZ.frac_field(x, y, z) raises(GeneratorsError, lambda: ZZ[x].inject(x)) def test_drop(): assert ZZ.drop(x) == ZZ assert ZZ[x].drop(x) == ZZ assert ZZ[x, y].drop(x) == ZZ[y] assert ZZ.frac_field(x).drop(x) == ZZ assert ZZ.frac_field(x, y).drop(x) == ZZ.frac_field(y) assert ZZ[x][y].drop(y) == ZZ[x] assert ZZ[x][y].drop(x) == ZZ[y] assert ZZ.frac_field(x)[y].drop(x) == ZZ[y] assert ZZ.frac_field(x)[y].drop(y) == ZZ.frac_field(x) Ky = FiniteExtension(Poly(x**2-1, x, domain=ZZ[y])) K = FiniteExtension(Poly(x**2-1, x, domain=ZZ)) assert Ky.drop(y) == K raises(GeneratorsError, lambda: Ky.drop(x)) def test_Domain_map(): seq = ZZ.map([1, 2, 3, 4]) assert all(ZZ.of_type(elt) for elt in seq) seq = ZZ.map([[1, 2, 3, 4]]) assert all(ZZ.of_type(elt) for elt in seq[0]) and len(seq) == 1 def test_Domain___eq__(): assert (ZZ[x, y] == ZZ[x, y]) is True assert (QQ[x, y] == QQ[x, y]) is True assert (ZZ[x, y] == QQ[x, y]) is False assert (QQ[x, y] == ZZ[x, y]) is False assert (ZZ.frac_field(x, y) == ZZ.frac_field(x, y)) is True assert (QQ.frac_field(x, y) == QQ.frac_field(x, y)) is True assert (ZZ.frac_field(x, y) == QQ.frac_field(x, y)) is False assert (QQ.frac_field(x, y) == ZZ.frac_field(x, y)) is False assert RealField()[x] == RR[x] def test_Domain__algebraic_field(): alg = ZZ.algebraic_field(sqrt(2)) assert alg.ext.minpoly == Poly(x**2 - 2) assert alg.dom == QQ alg = QQ.algebraic_field(sqrt(2)) assert alg.ext.minpoly == Poly(x**2 - 2) assert alg.dom == QQ alg = alg.algebraic_field(sqrt(3)) assert alg.ext.minpoly == Poly(x**4 - 10*x**2 + 1) assert alg.dom == QQ def test_PolynomialRing_from_FractionField(): F, x,y = field("x,y", ZZ) R, X,Y = ring("x,y", ZZ) f = (x**2 + y**2)/(x + 1) g = (x**2 + y**2)/4 h = x**2 + y**2 assert R.to_domain().from_FractionField(f, F.to_domain()) is None assert R.to_domain().from_FractionField(g, F.to_domain()) == X**2/4 + Y**2/4 assert R.to_domain().from_FractionField(h, F.to_domain()) == X**2 + Y**2 F, x,y = field("x,y", QQ) R, X,Y = ring("x,y", QQ) f = (x**2 + y**2)/(x + 1) g = (x**2 + y**2)/4 h = x**2 + y**2 assert R.to_domain().from_FractionField(f, F.to_domain()) is None assert R.to_domain().from_FractionField(g, F.to_domain()) == X**2/4 + Y**2/4 assert R.to_domain().from_FractionField(h, F.to_domain()) == X**2 + Y**2 def test_FractionField_from_PolynomialRing(): R, x,y = ring("x,y", QQ) F, X,Y = field("x,y", ZZ) f = 3*x**2 + 5*y**2 g = x**2/3 + y**2/5 assert F.to_domain().from_PolynomialRing(f, R.to_domain()) == 3*X**2 + 5*Y**2 assert F.to_domain().from_PolynomialRing(g, R.to_domain()) == (5*X**2 + 3*Y**2)/15 def test_FF_of_type(): assert FF(3).of_type(FF(3)(1)) is True assert FF(5).of_type(FF(5)(3)) is True assert FF(5).of_type(FF(7)(3)) is False def test___eq__(): assert not QQ[x] == ZZ[x] assert not QQ.frac_field(x) == ZZ.frac_field(x) def test_RealField_from_sympy(): assert RR.convert(S.Zero) == RR.dtype(0) assert RR.convert(S(0.0)) == RR.dtype(0.0) assert RR.convert(S.One) == RR.dtype(1) assert RR.convert(S(1.0)) == RR.dtype(1.0) assert RR.convert(sin(1)) == RR.dtype(sin(1).evalf()) def test_not_in_any_domain(): check = illegal + [x] + [ float(i) for i in illegal if i != S.ComplexInfinity] for dom in (ZZ, QQ, RR, CC, EX): for i in check: if i == x and dom == EX: continue assert i not in dom, (i, dom) raises(CoercionFailed, lambda: dom.convert(i)) def test_ModularInteger(): F3 = FF(3) a = F3(0) assert isinstance(a, F3.dtype) and a == 0 a = F3(1) assert isinstance(a, F3.dtype) and a == 1 a = F3(2) assert isinstance(a, F3.dtype) and a == 2 a = F3(3) assert isinstance(a, F3.dtype) and a == 0 a = F3(4) assert isinstance(a, F3.dtype) and a == 1 a = F3(F3(0)) assert isinstance(a, F3.dtype) and a == 0 a = F3(F3(1)) assert isinstance(a, F3.dtype) and a == 1 a = F3(F3(2)) assert isinstance(a, F3.dtype) and a == 2 a = F3(F3(3)) assert isinstance(a, F3.dtype) and a == 0 a = F3(F3(4)) assert isinstance(a, F3.dtype) and a == 1 a = -F3(1) assert isinstance(a, F3.dtype) and a == 2 a = -F3(2) assert isinstance(a, F3.dtype) and a == 1 a = 2 + F3(2) assert isinstance(a, F3.dtype) and a == 1 a = F3(2) + 2 assert isinstance(a, F3.dtype) and a == 1 a = F3(2) + F3(2) assert isinstance(a, F3.dtype) and a == 1 a = F3(2) + F3(2) assert isinstance(a, F3.dtype) and a == 1 a = 3 - F3(2) assert isinstance(a, F3.dtype) and a == 1 a = F3(3) - 2 assert isinstance(a, F3.dtype) and a == 1 a = F3(3) - F3(2) assert isinstance(a, F3.dtype) and a == 1 a = F3(3) - F3(2) assert isinstance(a, F3.dtype) and a == 1 a = 2*F3(2) assert isinstance(a, F3.dtype) and a == 1 a = F3(2)*2 assert isinstance(a, F3.dtype) and a == 1 a = F3(2)*F3(2) assert isinstance(a, F3.dtype) and a == 1 a = F3(2)*F3(2) assert isinstance(a, F3.dtype) and a == 1 a = 2/F3(2) assert isinstance(a, F3.dtype) and a == 1 a = F3(2)/2 assert isinstance(a, F3.dtype) and a == 1 a = F3(2)/F3(2) assert isinstance(a, F3.dtype) and a == 1 a = F3(2)/F3(2) assert isinstance(a, F3.dtype) and a == 1 a = 1 % F3(2) assert isinstance(a, F3.dtype) and a == 1 a = F3(1) % 2 assert isinstance(a, F3.dtype) and a == 1 a = F3(1) % F3(2) assert isinstance(a, F3.dtype) and a == 1 a = F3(1) % F3(2) assert isinstance(a, F3.dtype) and a == 1 a = F3(2)**0 assert isinstance(a, F3.dtype) and a == 1 a = F3(2)**1 assert isinstance(a, F3.dtype) and a == 2 a = F3(2)**2 assert isinstance(a, F3.dtype) and a == 1 F7 = FF(7) a = F7(3)**100000000000 assert isinstance(a, F7.dtype) and a == 4 a = F7(3)**-100000000000 assert isinstance(a, F7.dtype) and a == 2 a = F7(3)**S(2) assert isinstance(a, F7.dtype) and a == 2 assert bool(F3(3)) is False assert bool(F3(4)) is True F5 = FF(5) a = F5(1)**(-1) assert isinstance(a, F5.dtype) and a == 1 a = F5(2)**(-1) assert isinstance(a, F5.dtype) and a == 3 a = F5(3)**(-1) assert isinstance(a, F5.dtype) and a == 2 a = F5(4)**(-1) assert isinstance(a, F5.dtype) and a == 4 assert (F5(1) < F5(2)) is True assert (F5(1) <= F5(2)) is True assert (F5(1) > F5(2)) is False assert (F5(1) >= F5(2)) is False assert (F5(3) < F5(2)) is False assert (F5(3) <= F5(2)) is False assert (F5(3) > F5(2)) is True assert (F5(3) >= F5(2)) is True assert (F5(1) < F5(7)) is True assert (F5(1) <= F5(7)) is True assert (F5(1) > F5(7)) is False assert (F5(1) >= F5(7)) is False assert (F5(3) < F5(7)) is False assert (F5(3) <= F5(7)) is False assert (F5(3) > F5(7)) is True assert (F5(3) >= F5(7)) is True assert (F5(1) < 2) is True assert (F5(1) <= 2) is True assert (F5(1) > 2) is False assert (F5(1) >= 2) is False assert (F5(3) < 2) is False assert (F5(3) <= 2) is False assert (F5(3) > 2) is True assert (F5(3) >= 2) is True assert (F5(1) < 7) is True assert (F5(1) <= 7) is True assert (F5(1) > 7) is False assert (F5(1) >= 7) is False assert (F5(3) < 7) is False assert (F5(3) <= 7) is False assert (F5(3) > 7) is True assert (F5(3) >= 7) is True raises(NotInvertible, lambda: F5(0)**(-1)) raises(NotInvertible, lambda: F5(5)**(-1)) raises(ValueError, lambda: FF(0)) raises(ValueError, lambda: FF(2.1)) def test_QQ_int(): assert int(QQ(2**2000, 3**1250)) == 455431 assert int(QQ(2**100, 3)) == 422550200076076467165567735125 def test_RR_double(): assert RR(3.14) > 1e-50 assert RR(1e-13) > 1e-50 assert RR(1e-14) > 1e-50 assert RR(1e-15) > 1e-50 assert RR(1e-20) > 1e-50 assert RR(1e-40) > 1e-50 def test_RR_Float(): f1 = Float("1.01") f2 = Float("1.0000000000000000000001") assert f1._prec == 53 assert f2._prec == 80 assert RR(f1)-1 > 1e-50 assert RR(f2)-1 < 1e-50 # RR's precision is lower than f2's RR2 = RealField(prec=f2._prec) assert RR2(f1)-1 > 1e-50 assert RR2(f2)-1 > 1e-50 # RR's precision is equal to f2's def test_CC_double(): assert CC(3.14).real > 1e-50 assert CC(1e-13).real > 1e-50 assert CC(1e-14).real > 1e-50 assert CC(1e-15).real > 1e-50 assert CC(1e-20).real > 1e-50 assert CC(1e-40).real > 1e-50 assert CC(3.14j).imag > 1e-50 assert CC(1e-13j).imag > 1e-50 assert CC(1e-14j).imag > 1e-50 assert CC(1e-15j).imag > 1e-50 assert CC(1e-20j).imag > 1e-50 assert CC(1e-40j).imag > 1e-50 def test_gaussian_domains(): I = S.ImaginaryUnit a, b, c, d = [ZZ_I.convert(x) for x in (5, 2 + I, 3 - I, 5 - 5)] ZZ_I.gcd(a, b) == b ZZ_I.gcd(a, c) == b ZZ_I.lcm(a, b) == a ZZ_I.lcm(a, c) == d assert ZZ_I(3, 4) != QQ_I(3, 4) # XXX is this right or should QQ->ZZ if possible? assert ZZ_I(3, 0) != 3 # and should this go to Integer? assert QQ_I(S(3)/4, 0) != S(3)/4 # and this to Rational? assert ZZ_I(0, 0).quadrant() == 0 assert ZZ_I(-1, 0).quadrant() == 2 assert QQ_I.convert(QQ(3, 2)) == QQ_I(QQ(3, 2), QQ(0)) assert QQ_I.convert(QQ(3, 2), QQ) == QQ_I(QQ(3, 2), QQ(0)) for G in (QQ_I, ZZ_I): q = G(3, 4) assert str(q) == '3 + 4*I' assert q.parent() == G assert q._get_xy(pi) == (None, None) assert q._get_xy(2) == (2, 0) assert q._get_xy(2*I) == (0, 2) assert hash(q) == hash((3, 4)) assert G(1, 2) == G(1, 2) assert G(1, 2) != G(1, 3) assert G(3, 0) == G(3) assert q + q == G(6, 8) assert q - q == G(0, 0) assert 3 - q == -q + 3 == G(0, -4) assert 3 + q == q + 3 == G(6, 4) assert q * q == G(-7, 24) assert 3 * q == q * 3 == G(9, 12) assert q ** 0 == G(1, 0) assert q ** 1 == q assert q ** 2 == q * q == G(-7, 24) assert q ** 3 == q * q * q == G(-117, 44) assert 1 / q == q ** -1 == QQ_I(S(3)/25, - S(4)/25) assert q / 1 == QQ_I(3, 4) assert q / 2 == QQ_I(S(3)/2, 2) assert q/3 == QQ_I(1, S(4)/3) assert 3/q == QQ_I(S(9)/25, -S(12)/25) i, r = divmod(q, 2) assert 2*i + r == q i, r = divmod(2, q) assert q*i + r == G(2, 0) raises(ZeroDivisionError, lambda: q % 0) raises(ZeroDivisionError, lambda: q / 0) raises(ZeroDivisionError, lambda: q // 0) raises(ZeroDivisionError, lambda: divmod(q, 0)) raises(ZeroDivisionError, lambda: divmod(q, 0)) raises(TypeError, lambda: q + x) raises(TypeError, lambda: q - x) raises(TypeError, lambda: x + q) raises(TypeError, lambda: x - q) raises(TypeError, lambda: q * x) raises(TypeError, lambda: x * q) raises(TypeError, lambda: q / x) raises(TypeError, lambda: x / q) raises(TypeError, lambda: q // x) raises(TypeError, lambda: x // q) assert G.from_sympy(S(2)) == G(2, 0) assert G.to_sympy(G(2, 0)) == S(2) raises(CoercionFailed, lambda: G.from_sympy(pi)) PR = G.inject(x) assert isinstance(PR, PolynomialRing) assert PR.domain == G assert len(PR.gens) == 1 and PR.gens[0].as_expr() == x if G is QQ_I: AF = G.as_AlgebraicField() assert isinstance(AF, AlgebraicField) assert AF.domain == QQ assert AF.ext.args[0] == I for qi in [G(-1, 0), G(1, 0), G(0, -1), G(0, 1)]: assert G.is_negative(qi) is False assert G.is_positive(qi) is False assert G.is_nonnegative(qi) is False assert G.is_nonpositive(qi) is False domains = [ZZ_python(), QQ_python(), AlgebraicField(QQ, I)] if HAS_GMPY: domains += [ZZ_gmpy(), QQ_gmpy()] for K in domains: assert G.convert(K(2)) == G(2, 0) assert G.convert(K(2), K) == G(2, 0) for K in ZZ_I, QQ_I: assert G.convert(K(1, 1)) == G(1, 1) assert G.convert(K(1, 1), K) == G(1, 1) if G == ZZ_I: assert repr(q) == 'ZZ_I(3, 4)' assert q//3 == G(1, 1) assert 12//q == G(1, -2) assert 12 % q == G(1, 2) assert q % 2 == G(-1, 0) assert i == G(0, 0) assert r == G(2, 0) assert G.get_ring() == G assert G.get_field() == QQ_I else: assert repr(q) == 'QQ_I(3, 4)' assert G.get_ring() == ZZ_I assert G.get_field() == G assert q//3 == G(1, S(4)/3) assert 12//q == G(S(36)/25, -S(48)/25) assert 12 % q == G(0, 0) assert q % 2 == G(0, 0) assert i == G(S(6)/25, -S(8)/25), (G,i) assert r == G(0, 0) q2 = G(S(3)/2, S(5)/3) assert G.numer(q2) == ZZ_I(9, 10) assert G.denom(q2) == ZZ_I(6) def test_canonical_unit(): for K in [ZZ, QQ, RR]: # CC? assert K.canonical_unit(K(2)) == K(1) assert K.canonical_unit(K(-2)) == K(-1) for K in [ZZ_I, QQ_I]: i = K.from_sympy(I) assert K.canonical_unit(K(2)) == K(1) assert K.canonical_unit(K(2)*i) == -i assert K.canonical_unit(-K(2)) == K(-1) assert K.canonical_unit(-K(2)*i) == i K = ZZ[x] assert K.canonical_unit(K(x + 1)) == K(1) assert K.canonical_unit(K(-x + 1)) == K(-1) K = ZZ_I[x] assert K.canonical_unit(K.from_sympy(I*x)) == ZZ_I(0, -1) K = ZZ_I.frac_field(x, y) i = K.from_sympy(I) assert i / i == K.one assert (K.one + i)/(i - K.one) == -i def test_issue_18278(): assert str(RR(2).parent()) == 'RR' assert str(CC(2).parent()) == 'CC' def test_Domain_is_negative(): I = S.ImaginaryUnit a, b = [CC.convert(x) for x in (2 + I, 5)] assert CC.is_negative(a) == False assert CC.is_negative(b) == False def test_Domain_is_positive(): I = S.ImaginaryUnit a, b = [CC.convert(x) for x in (2 + I, 5)] assert CC.is_positive(a) == False assert CC.is_positive(b) == False def test_Domain_is_nonnegative(): I = S.ImaginaryUnit a, b = [CC.convert(x) for x in (2 + I, 5)] assert CC.is_nonnegative(a) == False assert CC.is_nonnegative(b) == False def test_Domain_is_nonpositive(): I = S.ImaginaryUnit a, b = [CC.convert(x) for x in (2 + I, 5)] assert CC.is_nonpositive(a) == False assert CC.is_nonpositive(b) == False
2c069f467f10cb66cc0569e50b6edfca261043b31f9828698d960cc4e3714c62
from sympy.testing.pytest import raises from sympy import Symbol, sympify from sympy.polys.matrices.normalforms import invariant_factors, smith_normal_form from sympy.polys.domains import ZZ, QQ from sympy.polys.matrices import DomainMatrix def test_smith_normal(): def DM(elems, domain): conv = lambda e: domain.from_sympy(sympify(e)) elems = [[conv(e) for e in row] for row in elems] return DomainMatrix(elems, (len(elems), len(elems[0])), domain) m = DM([[12, 6, 4, 8], [3, 9, 6, 12], [2, 16, 14, 28], [20, 10, 10, 20]], ZZ) smf = DM([[1, 0, 0, 0], [0, 10, 0, 0], [0, 0, -30, 0], [0, 0, 0, 0]], ZZ) assert smith_normal_form(m).to_dense() == smf x = Symbol('x') m = DM([[x-1, 1, -1], [ 0, x, -1], [ 0, -1, x]], QQ[x]) dx = m.domain.gens[0] assert invariant_factors(m) == (1, dx-1, dx**2-1) zr = DomainMatrix([], (0, 2), ZZ) zc = DomainMatrix([[], []], (2, 0), ZZ) assert smith_normal_form(zr).to_dense() == zr assert smith_normal_form(zc).to_dense() == zc assert smith_normal_form(DM([[2, 4]], ZZ)).to_dense() == DM([[2, 0]], ZZ) assert smith_normal_form(DM([[0, -2]], ZZ)).to_dense() == DM([[-2, 0]], ZZ) assert smith_normal_form(DM([[0], [-2]], ZZ)).to_dense() == DM([[-2], [0]], ZZ) m = DM([[3, 0, 0, 0], [0, 0, 0, 0], [0, 0, 2, 0]], ZZ) snf = DM([[1, 0, 0, 0], [0, 6, 0, 0], [0, 0, 0, 0]], ZZ) assert smith_normal_form(m).to_dense() == snf raises(ValueError, lambda: smith_normal_form(DM([[1]], ZZ[x])))
d44311f61a1f01c90f033abbe9af374625f41ce818a73c9efd2b75f9c3737b1f
from sympy.testing.pytest import raises from sympy.core.compatibility import HAS_GMPY from sympy.polys import ZZ, QQ from sympy.polys.matrices.ddm import DDM from sympy.polys.matrices.exceptions import ( DDMShapeError, NonInvertibleMatrixError, DDMDomainError, DDMBadInputError) def test_DDM_init(): items = [[ZZ(0), ZZ(1), ZZ(2)], [ZZ(3), ZZ(4), ZZ(5)]] shape = (2, 3) ddm = DDM(items, shape, ZZ) assert ddm.shape == shape assert ddm.rows == 2 assert ddm.cols == 3 assert ddm.domain == ZZ raises(DDMBadInputError, lambda: DDM([[ZZ(2), ZZ(3)]], (2, 2), ZZ)) raises(DDMBadInputError, lambda: DDM([[ZZ(1)], [ZZ(2), ZZ(3)]], (2, 2), ZZ)) def test_DDM_getsetitem(): ddm = DDM([[ZZ(2), ZZ(3)], [ZZ(4), ZZ(5)]], (2, 2), ZZ) assert ddm[0][0] == ZZ(2) assert ddm[0][1] == ZZ(3) assert ddm[1][0] == ZZ(4) assert ddm[1][1] == ZZ(5) raises(IndexError, lambda: ddm[2][0]) raises(IndexError, lambda: ddm[0][2]) ddm[0][0] = ZZ(-1) assert ddm[0][0] == ZZ(-1) def test_DDM_str(): ddm = DDM([[ZZ(0), ZZ(1)], [ZZ(2), ZZ(3)]], (2, 2), ZZ) if HAS_GMPY: # pragma: no cover assert str(ddm) == '[[0, 1], [2, 3]]' assert repr(ddm) == 'DDM([[mpz(0), mpz(1)], [mpz(2), mpz(3)]], (2, 2), ZZ)' else: # pragma: no cover assert repr(ddm) == 'DDM([[0, 1], [2, 3]], (2, 2), ZZ)' assert str(ddm) == '[[0, 1], [2, 3]]' def test_DDM_eq(): items = [[ZZ(0), ZZ(1)], [ZZ(2), ZZ(3)]] ddm1 = DDM(items, (2, 2), ZZ) ddm2 = DDM(items, (2, 2), ZZ) assert (ddm1 == ddm1) is True assert (ddm1 == items) is False assert (items == ddm1) is False assert (ddm1 == ddm2) is True assert (ddm2 == ddm1) is True assert (ddm1 != ddm1) is False assert (ddm1 != items) is True assert (items != ddm1) is True assert (ddm1 != ddm2) is False assert (ddm2 != ddm1) is False ddm3 = DDM([[ZZ(0), ZZ(1)], [ZZ(3), ZZ(3)]], (2, 2), ZZ) ddm3 = DDM(items, (2, 2), QQ) assert (ddm1 == ddm3) is False assert (ddm3 == ddm1) is False assert (ddm1 != ddm3) is True assert (ddm3 != ddm1) is True def test_DDM_convert_to(): ddm = DDM([[ZZ(1), ZZ(2)]], (1, 2), ZZ) assert ddm.convert_to(ZZ) == ddm ddmq = ddm.convert_to(QQ) assert ddmq.domain == QQ def test_DDM_zeros(): ddmz = DDM.zeros((3, 4), QQ) assert list(ddmz) == [[QQ(0)] * 4] * 3 assert ddmz.shape == (3, 4) assert ddmz.domain == QQ def test_DDM_ones(): ddmone = DDM.ones((2, 3), QQ) assert list(ddmone) == [[QQ(1)] * 3] * 2 assert ddmone.shape == (2, 3) assert ddmone.domain == QQ def test_DDM_eye(): ddmz = DDM.eye(3, QQ) f = lambda i, j: QQ(1) if i == j else QQ(0) assert list(ddmz) == [[f(i, j) for i in range(3)] for j in range(3)] assert ddmz.shape == (3, 3) assert ddmz.domain == QQ def test_DDM_copy(): ddm1 = DDM([[QQ(1)], [QQ(2)]], (2, 1), QQ) ddm2 = ddm1.copy() assert (ddm1 == ddm2) is True ddm1[0][0] = QQ(-1) assert (ddm1 == ddm2) is False ddm2[0][0] = QQ(-1) assert (ddm1 == ddm2) is True def test_DDM_transpose(): ddm = DDM([[QQ(1)], [QQ(2)]], (2, 1), QQ) ddmT = DDM([[QQ(1), QQ(2)]], (1, 2), QQ) assert ddm.transpose() == ddmT ddm02 = DDM([], (0, 2), QQ) ddm02T = DDM([[], []], (2, 0), QQ) assert ddm02.transpose() == ddm02T assert ddm02T.transpose() == ddm02 ddm0 = DDM([], (0, 0), QQ) assert ddm0.transpose() == ddm0 def test_DDM_add(): A = DDM([[ZZ(1)], [ZZ(2)]], (2, 1), ZZ) B = DDM([[ZZ(3)], [ZZ(4)]], (2, 1), ZZ) C = DDM([[ZZ(4)], [ZZ(6)]], (2, 1), ZZ) AQ = DDM([[QQ(1)], [QQ(2)]], (2, 1), QQ) assert A + B == A.add(B) == C raises(DDMShapeError, lambda: A + DDM([[ZZ(5)]], (1, 1), ZZ)) raises(TypeError, lambda: A + ZZ(1)) raises(TypeError, lambda: ZZ(1) + A) raises(DDMDomainError, lambda: A + AQ) raises(DDMDomainError, lambda: AQ + A) def test_DDM_sub(): A = DDM([[ZZ(1)], [ZZ(2)]], (2, 1), ZZ) B = DDM([[ZZ(3)], [ZZ(4)]], (2, 1), ZZ) C = DDM([[ZZ(-2)], [ZZ(-2)]], (2, 1), ZZ) AQ = DDM([[QQ(1)], [QQ(2)]], (2, 1), QQ) D = DDM([[ZZ(5)]], (1, 1), ZZ) assert A - B == A.sub(B) == C raises(TypeError, lambda: A - ZZ(1)) raises(TypeError, lambda: ZZ(1) - A) raises(DDMShapeError, lambda: A - D) raises(DDMShapeError, lambda: D - A) raises(DDMShapeError, lambda: A.sub(D)) raises(DDMShapeError, lambda: D.sub(A)) raises(DDMDomainError, lambda: A - AQ) raises(DDMDomainError, lambda: AQ - A) raises(DDMDomainError, lambda: A.sub(AQ)) raises(DDMDomainError, lambda: AQ.sub(A)) def test_DDM_neg(): A = DDM([[ZZ(1)], [ZZ(2)]], (2, 1), ZZ) An = DDM([[ZZ(-1)], [ZZ(-2)]], (2, 1), ZZ) assert -A == A.neg() == An assert -An == An.neg() == A def test_DDM_mul(): A = DDM([[ZZ(1)]], (1, 1), ZZ) A2 = DDM([[ZZ(2)]], (1, 1), ZZ) assert A * ZZ(2) == A2 assert ZZ(2) * A == A2 raises(TypeError, lambda: [[1]] * A) raises(TypeError, lambda: A * [[1]]) def test_DDM_matmul(): A = DDM([[ZZ(1)], [ZZ(2)]], (2, 1), ZZ) B = DDM([[ZZ(3), ZZ(4)]], (1, 2), ZZ) AB = DDM([[ZZ(3), ZZ(4)], [ZZ(6), ZZ(8)]], (2, 2), ZZ) BA = DDM([[ZZ(11)]], (1, 1), ZZ) assert A @ B == A.matmul(B) == AB assert B @ A == B.matmul(A) == BA raises(TypeError, lambda: A @ 1) raises(TypeError, lambda: A @ [[3, 4]]) Bq = DDM([[QQ(3), QQ(4)]], (1, 2), QQ) raises(DDMDomainError, lambda: A @ Bq) raises(DDMDomainError, lambda: Bq @ A) C = DDM([[ZZ(1)]], (1, 1), ZZ) assert A @ C == A.matmul(C) == A raises(DDMShapeError, lambda: C @ A) raises(DDMShapeError, lambda: C.matmul(A)) Z04 = DDM([], (0, 4), ZZ) Z40 = DDM([[]]*4, (4, 0), ZZ) Z50 = DDM([[]]*5, (5, 0), ZZ) Z05 = DDM([], (0, 5), ZZ) Z45 = DDM([[0] * 5] * 4, (4, 5), ZZ) Z54 = DDM([[0] * 4] * 5, (5, 4), ZZ) Z00 = DDM([], (0, 0), ZZ) assert Z04 @ Z45 == Z04.matmul(Z45) == Z05 assert Z45 @ Z50 == Z45.matmul(Z50) == Z40 assert Z00 @ Z04 == Z00.matmul(Z04) == Z04 assert Z50 @ Z00 == Z50.matmul(Z00) == Z50 assert Z00 @ Z00 == Z00.matmul(Z00) == Z00 assert Z50 @ Z04 == Z50.matmul(Z04) == Z54 raises(DDMShapeError, lambda: Z05 @ Z40) raises(DDMShapeError, lambda: Z05.matmul(Z40)) def test_DDM_hstack(): A = DDM([[ZZ(1), ZZ(2), ZZ(3)]], (1, 3), ZZ) B = DDM([[ZZ(4), ZZ(5)]], (1, 2), ZZ) Ah = A.hstack(B) assert Ah.shape == (1, 5) assert Ah.domain == ZZ assert Ah == DDM([[ZZ(1), ZZ(2), ZZ(3), ZZ(4), ZZ(5)]], (1, 5), ZZ) def test_DDM_vstack(): A = DDM([[ZZ(1)], [ZZ(2)], [ZZ(3)]], (3, 1), ZZ) B = DDM([[ZZ(4)], [ZZ(5)]], (2, 1), ZZ) Ah = A.vstack(B) assert Ah.shape == (5, 1) assert Ah.domain == ZZ assert Ah == DDM([[ZZ(1)], [ZZ(2)], [ZZ(3)], [ZZ(4)], [ZZ(5)]], (5, 1), ZZ) def test_DDM_applyfunc(): A = DDM([[ZZ(1), ZZ(2), ZZ(3)]], (1, 3), ZZ) B = DDM([[ZZ(2), ZZ(4), ZZ(6)]], (1, 3), ZZ) assert A.applyfunc(lambda x: 2*x, ZZ) == B def test_DDM_rref(): A = DDM([], (0, 4), QQ) assert A.rref() == (A, []) A = DDM([[QQ(0), QQ(1)], [QQ(1), QQ(1)]], (2, 2), QQ) Ar = DDM([[QQ(1), QQ(0)], [QQ(0), QQ(1)]], (2, 2), QQ) pivots = [0, 1] assert A.rref() == (Ar, pivots) A = DDM([[QQ(1), QQ(2), QQ(1)], [QQ(3), QQ(4), QQ(1)]], (2, 3), QQ) Ar = DDM([[QQ(1), QQ(0), QQ(-1)], [QQ(0), QQ(1), QQ(1)]], (2, 3), QQ) pivots = [0, 1] assert A.rref() == (Ar, pivots) A = DDM([[QQ(3), QQ(4), QQ(1)], [QQ(1), QQ(2), QQ(1)]], (2, 3), QQ) Ar = DDM([[QQ(1), QQ(0), QQ(-1)], [QQ(0), QQ(1), QQ(1)]], (2, 3), QQ) pivots = [0, 1] assert A.rref() == (Ar, pivots) A = DDM([[QQ(1), QQ(0)], [QQ(1), QQ(3)], [QQ(0), QQ(1)]], (3, 2), QQ) Ar = DDM([[QQ(1), QQ(0)], [QQ(0), QQ(1)], [QQ(0), QQ(0)]], (3, 2), QQ) pivots = [0, 1] assert A.rref() == (Ar, pivots) A = DDM([[QQ(1), QQ(0), QQ(1)], [QQ(3), QQ(0), QQ(1)]], (2, 3), QQ) Ar = DDM([[QQ(1), QQ(0), QQ(0)], [QQ(0), QQ(0), QQ(1)]], (2, 3), QQ) pivots = [0, 2] assert A.rref() == (Ar, pivots) def test_DDM_nullspace(): A = DDM([[QQ(1), QQ(1)], [QQ(1), QQ(1)]], (2, 2), QQ) Anull = DDM([[QQ(-1), QQ(1)]], (1, 2), QQ) nonpivots = [1] assert A.nullspace() == (Anull, nonpivots) def test_DDM_particular(): A = DDM([[QQ(1), QQ(0)]], (1, 2), QQ) assert A.particular() == DDM.zeros((1, 1), QQ) def test_DDM_det(): # 0x0 case A = DDM([], (0, 0), ZZ) assert A.det() == ZZ(1) # 1x1 case A = DDM([[ZZ(2)]], (1, 1), ZZ) assert A.det() == ZZ(2) # 2x2 case A = DDM([[ZZ(1), ZZ(2)], [ZZ(3), ZZ(4)]], (2, 2), ZZ) assert A.det() == ZZ(-2) # 3x3 with swap A = DDM([[ZZ(1), ZZ(2), ZZ(3)], [ZZ(1), ZZ(2), ZZ(4)], [ZZ(1), ZZ(2), ZZ(5)]], (3, 3), ZZ) assert A.det() == ZZ(0) # 2x2 QQ case A = DDM([[QQ(1, 2), QQ(1, 2)], [QQ(1, 3), QQ(1, 4)]], (2, 2), QQ) assert A.det() == QQ(-1, 24) # Nonsquare error A = DDM([[ZZ(1)], [ZZ(2)]], (2, 1), ZZ) raises(DDMShapeError, lambda: A.det()) # Nonsquare error with empty matrix A = DDM([], (0, 1), ZZ) raises(DDMShapeError, lambda: A.det()) def test_DDM_inv(): A = DDM([[QQ(1, 1), QQ(2, 1)], [QQ(3, 1), QQ(4, 1)]], (2, 2), QQ) Ainv = DDM([[QQ(-2, 1), QQ(1, 1)], [QQ(3, 2), QQ(-1, 2)]], (2, 2), QQ) assert A.inv() == Ainv A = DDM([[QQ(1), QQ(2)]], (1, 2), QQ) raises(DDMShapeError, lambda: A.inv()) A = DDM([[ZZ(2)]], (1, 1), ZZ) raises(ValueError, lambda: A.inv()) A = DDM([], (0, 0), QQ) assert A.inv() == A A = DDM([[QQ(1), QQ(2)], [QQ(2), QQ(4)]], (2, 2), QQ) raises(NonInvertibleMatrixError, lambda: A.inv()) def test_DDM_lu(): A = DDM([[QQ(1), QQ(2)], [QQ(3), QQ(4)]], (2, 2), QQ) L, U, swaps = A.lu() assert L == DDM([[QQ(1), QQ(0)], [QQ(3), QQ(1)]], (2, 2), QQ) assert U == DDM([[QQ(1), QQ(2)], [QQ(0), QQ(-2)]], (2, 2), QQ) assert swaps == [] A = [[1, 0, 0, 0], [0, 0, 0, 0], [0, 0, 1, 1], [0, 0, 1, 2]] Lexp = [[1, 0, 0, 0], [0, 1, 0, 0], [0, 0, 1, 0], [0, 0, 1, 1]] Uexp = [[1, 0, 0, 0], [0, 0, 0, 0], [0, 0, 1, 1], [0, 0, 0, 1]] to_dom = lambda rows, dom: [[dom(e) for e in row] for row in rows] A = DDM(to_dom(A, QQ), (4, 4), QQ) Lexp = DDM(to_dom(Lexp, QQ), (4, 4), QQ) Uexp = DDM(to_dom(Uexp, QQ), (4, 4), QQ) L, U, swaps = A.lu() assert L == Lexp assert U == Uexp assert swaps == [] def test_DDM_lu_solve(): # Basic example A = DDM([[QQ(1), QQ(2)], [QQ(3), QQ(4)]], (2, 2), QQ) b = DDM([[QQ(1)], [QQ(2)]], (2, 1), QQ) x = DDM([[QQ(0)], [QQ(1, 2)]], (2, 1), QQ) assert A.lu_solve(b) == x # Example with swaps A = DDM([[QQ(0), QQ(2)], [QQ(3), QQ(4)]], (2, 2), QQ) assert A.lu_solve(b) == x # Overdetermined, consistent A = DDM([[QQ(1), QQ(2)], [QQ(3), QQ(4)], [QQ(5), QQ(6)]], (3, 2), QQ) b = DDM([[QQ(1)], [QQ(2)], [QQ(3)]], (3, 1), QQ) assert A.lu_solve(b) == x # Overdetermined, inconsistent b = DDM([[QQ(1)], [QQ(2)], [QQ(4)]], (3, 1), QQ) raises(NonInvertibleMatrixError, lambda: A.lu_solve(b)) # Square, noninvertible A = DDM([[QQ(1), QQ(2)], [QQ(1), QQ(2)]], (2, 2), QQ) b = DDM([[QQ(1)], [QQ(2)]], (2, 1), QQ) raises(NonInvertibleMatrixError, lambda: A.lu_solve(b)) # Underdetermined A = DDM([[QQ(1), QQ(2)]], (1, 2), QQ) b = DDM([[QQ(3)]], (1, 1), QQ) raises(NotImplementedError, lambda: A.lu_solve(b)) # Domain mismatch bz = DDM([[ZZ(1)], [ZZ(2)]], (2, 1), ZZ) raises(DDMDomainError, lambda: A.lu_solve(bz)) # Shape mismatch b3 = DDM([[QQ(1)], [QQ(2)], [QQ(3)]], (3, 1), QQ) raises(DDMShapeError, lambda: A.lu_solve(b3)) def test_DDM_charpoly(): A = DDM([], (0, 0), ZZ) assert A.charpoly() == [ZZ(1)] A = DDM([ [ZZ(1), ZZ(2), ZZ(3)], [ZZ(4), ZZ(5), ZZ(6)], [ZZ(7), ZZ(8), ZZ(9)]], (3, 3), ZZ) Avec = [ZZ(1), ZZ(-15), ZZ(-18), ZZ(0)] assert A.charpoly() == Avec A = DDM([[ZZ(1), ZZ(2)]], (1, 2), ZZ) raises(DDMShapeError, lambda: A.charpoly()) def test_DDM_getitem(): dm = DDM([ [ZZ(1), ZZ(2), ZZ(3)], [ZZ(4), ZZ(5), ZZ(6)], [ZZ(7), ZZ(8), ZZ(9)]], (3, 3), ZZ) assert dm.getitem(1, 1) == ZZ(5) assert dm.getitem(1, -2) == ZZ(5) assert dm.getitem(-1, -3) == ZZ(7) raises(IndexError, lambda: dm.getitem(3, 3)) def test_DDM_extract_slice(): dm = DDM([ [ZZ(1), ZZ(2), ZZ(3)], [ZZ(4), ZZ(5), ZZ(6)], [ZZ(7), ZZ(8), ZZ(9)]], (3, 3), ZZ) assert dm.extract_slice(slice(0, 3), slice(0, 3)) == dm assert dm.extract_slice(slice(1, 3), slice(-2)) == DDM([[4], [7]], (2, 1), ZZ) assert dm.extract_slice(slice(1, 3), slice(-2)) == DDM([[4], [7]], (2, 1), ZZ) assert dm.extract_slice(slice(2, 3), slice(-2)) == DDM([[ZZ(7)]], (1, 1), ZZ) assert dm.extract_slice(slice(0, 2), slice(-2)) == DDM([[1], [4]], (2, 1), ZZ) assert dm.extract_slice(slice(-1), slice(-1)) == DDM([[1, 2], [4, 5]], (2, 2), ZZ) assert dm.extract_slice(slice(2), slice(3, 4)) == DDM([[], []], (2, 0), ZZ) assert dm.extract_slice(slice(3, 4), slice(2)) == DDM([], (0, 2), ZZ) assert dm.extract_slice(slice(3, 4), slice(3, 4)) == DDM([], (0, 0), ZZ)
f4740bf795e5c725c73437ff50137db7575affdb3244d64639bec82a49a39fe5
from sympy.testing.pytest import raises from sympy.core.symbol import S from sympy.polys import ZZ, QQ from sympy.polys.matrices.domainscalar import DomainScalar from sympy.polys.matrices.domainmatrix import DomainMatrix def test_DomainScalar___new__(): raises(TypeError, lambda: DomainScalar(ZZ(1), QQ)) raises(TypeError, lambda: DomainScalar(ZZ(1), 1)) def test_DomainScalar_new(): A = DomainScalar(ZZ(1), ZZ) B = A.new(ZZ(4), ZZ) assert B == DomainScalar(ZZ(4), ZZ) def test_DomainScalar_repr(): A = DomainScalar(ZZ(1), ZZ) assert repr(A) in {'1', 'mpz(1)'} def test_DomainScalar_from_sympy(): expr = S(1) B = DomainScalar.from_sympy(expr) assert B == DomainScalar(ZZ(1), ZZ) def test_DomainScalar_to_sympy(): B = DomainScalar(ZZ(1), ZZ) expr = B.to_sympy() assert expr.is_Integer and expr == 1 def test_DomainScalar_to_domain(): A = DomainScalar(ZZ(1), ZZ) B = A.to_domain(QQ) assert B == DomainScalar(QQ(1), QQ) def test_DomainScalar_convert_to(): A = DomainScalar(ZZ(1), ZZ) B = A.convert_to(QQ) assert B == DomainScalar(QQ(1), QQ) def test_DomainScalar_unify(): A = DomainScalar(ZZ(1), ZZ) B = DomainScalar(QQ(2), QQ) A, B = A.unify(B) assert A.domain == B.domain == QQ def test_DomainScalar_add(): A = DomainScalar(ZZ(1), ZZ) B = DomainScalar(QQ(2), QQ) assert A + B == DomainScalar(QQ(3), QQ) raises(TypeError, lambda: A + 1.5) def test_DomainScalar_sub(): A = DomainScalar(ZZ(1), ZZ) B = DomainScalar(QQ(2), QQ) assert A - B == DomainScalar(QQ(-1), QQ) raises(TypeError, lambda: A - 1.5) def test_DomainScalar_mul(): A = DomainScalar(ZZ(1), ZZ) B = DomainScalar(QQ(2), QQ) dm = DomainMatrix([[ZZ(1), ZZ(2)], [ZZ(3), ZZ(4)]], (2, 2), ZZ) assert A * B == DomainScalar(QQ(2), QQ) assert A * dm == dm assert B * 2 == DomainScalar(QQ(4), QQ) raises(TypeError, lambda: A * 1.5) def test_DomainScalar_floordiv(): A = DomainScalar(ZZ(-5), ZZ) B = DomainScalar(QQ(2), QQ) assert A // B == DomainScalar(QQ(-5, 2), QQ) C = DomainScalar(ZZ(2), ZZ) assert A // C == DomainScalar(ZZ(-3), ZZ) raises(TypeError, lambda: A // 1.5) def test_DomainScalar_mod(): A = DomainScalar(ZZ(5), ZZ) B = DomainScalar(QQ(2), QQ) assert A % B == DomainScalar(QQ(0), QQ) C = DomainScalar(ZZ(2), ZZ) assert A % C == DomainScalar(ZZ(1), ZZ) raises(TypeError, lambda: A % 1.5) def test_DomainScalar_divmod(): A = DomainScalar(ZZ(5), ZZ) B = DomainScalar(QQ(2), QQ) assert divmod(A, B) == (DomainScalar(QQ(5, 2), QQ), DomainScalar(QQ(0), QQ)) C = DomainScalar(ZZ(2), ZZ) assert divmod(A, C) == (DomainScalar(ZZ(2), ZZ), DomainScalar(ZZ(1), ZZ)) raises(TypeError, lambda: divmod(A, 1.5)) def test_DomainScalar_pow(): A = DomainScalar(ZZ(-5), ZZ) B = A**(2) assert B == DomainScalar(ZZ(25), ZZ) raises(TypeError, lambda: A**(1.5)) def test_DomainScalar_pos(): A = DomainScalar(QQ(2), QQ) B = DomainScalar(QQ(2), QQ) assert +A == B def test_DomainScalar_eq(): A = DomainScalar(QQ(2), QQ) assert A == A B = DomainScalar(ZZ(-5), ZZ) assert A != B C = DomainScalar(ZZ(2), ZZ) assert A != C D = [1] assert A != D def test_DomainScalar_isZero(): A = DomainScalar(ZZ(0), ZZ) assert A.is_zero() == True B = DomainScalar(ZZ(1), ZZ) assert B.is_zero() == False def test_DomainScalar_isOne(): A = DomainScalar(ZZ(1), ZZ) assert A.is_one() == True B = DomainScalar(ZZ(0), ZZ) assert B.is_one() == False
1096639da63ed3f1bb4e2cb6fc04fe256a32c27eaaf6397b19557cf0b40e1e6b
from sympy.testing.pytest import raises from sympy.core.numbers import Rational from sympy.functions import sqrt from sympy.matrices.common import (NonInvertibleMatrixError, NonSquareMatrixError, ShapeError) from sympy.matrices.dense import Matrix from sympy.polys import ZZ, QQ from sympy.polys.matrices.domainmatrix import DomainMatrix, DomainScalar from sympy.polys.matrices.exceptions import (DDMBadInputError, DDMDomainError, DDMShapeError, DDMFormatError) from sympy.polys.matrices.ddm import DDM from sympy.polys.matrices.sdm import SDM def test_DomainMatrix_init(): lol = [[ZZ(1), ZZ(2)], [ZZ(3), ZZ(4)]] dod = {0: {0: ZZ(1), 1:ZZ(2)}, 1: {0:ZZ(3), 1:ZZ(4)}} ddm = DDM(lol, (2, 2), ZZ) sdm = SDM(dod, (2, 2), ZZ) A = DomainMatrix(lol, (2, 2), ZZ) assert A.rep == ddm assert A.shape == (2, 2) assert A.domain == ZZ A = DomainMatrix(dod, (2, 2), ZZ) assert A.rep == sdm assert A.shape == (2, 2) assert A.domain == ZZ raises(TypeError, lambda: DomainMatrix(ddm, (2, 2), ZZ)) raises(TypeError, lambda: DomainMatrix(sdm, (2, 2), ZZ)) raises(TypeError, lambda: DomainMatrix(Matrix([[1]]), (1, 1), ZZ)) for fmt, rep in [('sparse', sdm), ('dense', ddm)]: A = DomainMatrix(lol, (2, 2), ZZ, fmt=fmt) assert A.rep == rep A = DomainMatrix(dod, (2, 2), ZZ, fmt=fmt) assert A.rep == rep raises(ValueError, lambda: DomainMatrix(lol, (2, 2), ZZ, fmt='invalid')) raises(DDMBadInputError, lambda: DomainMatrix([[ZZ(1), ZZ(2)]], (2, 2), ZZ)) def test_DomainMatrix_from_rep(): ddm = DDM([[ZZ(1), ZZ(2)], [ZZ(3), ZZ(4)]], (2, 2), ZZ) A = DomainMatrix.from_rep(ddm) assert A.rep == ddm assert A.shape == (2, 2) assert A.domain == ZZ sdm = SDM({0: {0: ZZ(1), 1:ZZ(2)}, 1: {0:ZZ(3), 1:ZZ(4)}}, (2, 2), ZZ) A = DomainMatrix.from_rep(sdm) assert A.rep == sdm assert A.shape == (2, 2) assert A.domain == ZZ A = DomainMatrix([[ZZ(1)]], (1, 1), ZZ) raises(TypeError, lambda: DomainMatrix.from_rep(A)) def test_DomainMatrix_from_list_sympy(): ddm = DDM([[ZZ(1), ZZ(2)], [ZZ(3), ZZ(4)]], (2, 2), ZZ) A = DomainMatrix.from_list_sympy(2, 2, [[1, 2], [3, 4]]) assert A.rep == ddm assert A.shape == (2, 2) assert A.domain == ZZ K = QQ.algebraic_field(sqrt(2)) ddm = DDM( [[K.convert(1 + sqrt(2)), K.convert(2 + sqrt(2))], [K.convert(3 + sqrt(2)), K.convert(4 + sqrt(2))]], (2, 2), K ) A = DomainMatrix.from_list_sympy( 2, 2, [[1 + sqrt(2), 2 + sqrt(2)], [3 + sqrt(2), 4 + sqrt(2)]], extension=True) assert A.rep == ddm assert A.shape == (2, 2) assert A.domain == K def test_DomainMatrix_from_dict_sympy(): sdm = SDM({0: {0: QQ(1, 2)}, 1: {1: QQ(2, 3)}}, (2, 2), QQ) sympy_dict = {0: {0: Rational(1, 2)}, 1: {1: Rational(2, 3)}} A = DomainMatrix.from_dict_sympy(2, 2, sympy_dict) assert A.rep == sdm assert A.shape == (2, 2) assert A.domain == QQ fds = DomainMatrix.from_dict_sympy raises(DDMBadInputError, lambda: fds(2, 2, {3: {0: Rational(1, 2)}})) raises(DDMBadInputError, lambda: fds(2, 2, {0: {3: Rational(1, 2)}})) def test_DomainMatrix_from_Matrix(): sdm = SDM({0: {0: ZZ(1), 1: ZZ(2)}, 1: {0: ZZ(3), 1: ZZ(4)}}, (2, 2), ZZ) A = DomainMatrix.from_Matrix(Matrix([[1, 2], [3, 4]])) assert A.rep == sdm assert A.shape == (2, 2) assert A.domain == ZZ K = QQ.algebraic_field(sqrt(2)) sdm = SDM( {0: {0: K.convert(1 + sqrt(2)), 1: K.convert(2 + sqrt(2))}, 1: {0: K.convert(3 + sqrt(2)), 1: K.convert(4 + sqrt(2))}}, (2, 2), K ) A = DomainMatrix.from_Matrix( Matrix([[1 + sqrt(2), 2 + sqrt(2)], [3 + sqrt(2), 4 + sqrt(2)]]), extension=True) assert A.rep == sdm assert A.shape == (2, 2) assert A.domain == K A = DomainMatrix.from_Matrix(Matrix([[QQ(1, 2), QQ(3, 4)], [QQ(0, 1), QQ(0, 1)]]), fmt='dense') ddm = DDM([[QQ(1, 2), QQ(3, 4)], [QQ(0, 1), QQ(0, 1)]], (2, 2), QQ) assert A.rep == ddm assert A.shape == (2, 2) assert A.domain == QQ def test_DomainMatrix_eq(): A = DomainMatrix([[ZZ(1), ZZ(2)], [ZZ(3), ZZ(4)]], (2, 2), ZZ) assert A == A B = DomainMatrix([[ZZ(1), ZZ(2)], [ZZ(3), ZZ(1)]], (2, 2), ZZ) assert A != B C = [[ZZ(1), ZZ(2)], [ZZ(3), ZZ(4)]] assert A != C def test_DomainMatrix_get_domain(): K, items = DomainMatrix.get_domain([1, 2, 3, 4]) assert items == [ZZ(1), ZZ(2), ZZ(3), ZZ(4)] assert K == ZZ K, items = DomainMatrix.get_domain([1, 2, 3, Rational(1, 2)]) assert items == [QQ(1), QQ(2), QQ(3), QQ(1, 2)] assert K == QQ def test_DomainMatrix_convert_to(): A = DomainMatrix([[ZZ(1), ZZ(2)], [ZZ(3), ZZ(4)]], (2, 2), ZZ) Aq = A.convert_to(QQ) assert Aq == DomainMatrix([[QQ(1), QQ(2)], [QQ(3), QQ(4)]], (2, 2), QQ) def test_DomainMatrix_to_field(): A = DomainMatrix([[ZZ(1), ZZ(2)], [ZZ(3), ZZ(4)]], (2, 2), ZZ) Aq = A.to_field() assert Aq == DomainMatrix([[QQ(1), QQ(2)], [QQ(3), QQ(4)]], (2, 2), QQ) def test_DomainMatrix_to_sparse(): A = DomainMatrix([[ZZ(1), ZZ(2)], [ZZ(3), ZZ(4)]], (2, 2), ZZ) A_sparse = A.to_sparse() assert A_sparse.rep == {0: {0: 1, 1: 2}, 1: {0: 3, 1: 4}} def test_DomainMatrix_to_dense(): A = DomainMatrix({0: {0: 1, 1: 2}, 1: {0: 3, 1: 4}}, (2, 2), ZZ) A_dense = A.to_dense() assert A_dense.rep == DDM([[1, 2], [3, 4]], (2, 2), ZZ) def test_DomainMatrix_unify(): Az = DomainMatrix([[ZZ(1), ZZ(2)], [ZZ(3), ZZ(4)]], (2, 2), ZZ) Aq = DomainMatrix([[QQ(1), QQ(2)], [QQ(3), QQ(4)]], (2, 2), QQ) assert Az.unify(Az) == (Az, Az) assert Az.unify(Aq) == (Aq, Aq) assert Aq.unify(Az) == (Aq, Aq) assert Aq.unify(Aq) == (Aq, Aq) As = DomainMatrix({0: {1: ZZ(1)}, 1:{0:ZZ(2)}}, (2, 2), ZZ) Ad = DomainMatrix([[ZZ(1), ZZ(2)], [ZZ(3), ZZ(4)]], (2, 2), ZZ) assert As.unify(As) == (As, As) assert Ad.unify(Ad) == (Ad, Ad) Bs, Bd = As.unify(Ad, fmt='dense') assert Bs.rep == DDM([[0, 1], [2, 0]], (2, 2), ZZ) assert Bd.rep == DDM([[1, 2],[3, 4]], (2, 2), ZZ) Bs, Bd = As.unify(Ad, fmt='sparse') assert Bs.rep == SDM({0: {1: 1}, 1: {0: 2}}, (2, 2), ZZ) assert Bd.rep == SDM({0: {0: 1, 1: 2}, 1: {0: 3, 1: 4}}, (2, 2), ZZ) raises(ValueError, lambda: As.unify(Ad, fmt='invalid')) def test_DomainMatrix_to_Matrix(): A = DomainMatrix([[ZZ(1), ZZ(2)], [ZZ(3), ZZ(4)]], (2, 2), ZZ) assert A.to_Matrix() == Matrix([[1, 2], [3, 4]]) def test_DomainMatrix_repr(): A = DomainMatrix([[ZZ(1), ZZ(2)], [ZZ(3), ZZ(4)]], (2, 2), ZZ) assert repr(A) == 'DomainMatrix([[1, 2], [3, 4]], (2, 2), ZZ)' def test_DomainMatrix_transpose(): A = DomainMatrix([[ZZ(1), ZZ(2)], [ZZ(3), ZZ(4)]], (2, 2), ZZ) AT = DomainMatrix([[ZZ(1), ZZ(3)], [ZZ(2), ZZ(4)]], (2, 2), ZZ) assert A.transpose() == AT def test_DomainMatrix_flat(): A = DomainMatrix([[ZZ(1), ZZ(2)], [ZZ(3), ZZ(4)]], (2, 2), ZZ) assert A.flat() == [ZZ(1), ZZ(2), ZZ(3), ZZ(4)] def test_DomainMatrix_is_zero_matrix(): A = DomainMatrix([[ZZ(1)]], (1, 1), ZZ) B = DomainMatrix([[ZZ(0)]], (1, 1), ZZ) assert A.is_zero_matrix is False assert B.is_zero_matrix is True def test_DomainMatrix_add(): A = DomainMatrix([[ZZ(1), ZZ(2)], [ZZ(3), ZZ(4)]], (2, 2), ZZ) B = DomainMatrix([[ZZ(2), ZZ(4)], [ZZ(6), ZZ(8)]], (2, 2), ZZ) assert A + A == A.add(A) == B A = DomainMatrix([[ZZ(1), ZZ(2)], [ZZ(3), ZZ(4)]], (2, 2), ZZ) L = [[2, 3], [3, 4]] raises(TypeError, lambda: A + L) raises(TypeError, lambda: L + A) A1 = DomainMatrix([[ZZ(1), ZZ(2)], [ZZ(3), ZZ(4)]], (2, 2), ZZ) A2 = DomainMatrix([[ZZ(1), ZZ(2)]], (1, 2), ZZ) raises(DDMShapeError, lambda: A1 + A2) raises(DDMShapeError, lambda: A2 + A1) raises(DDMShapeError, lambda: A1.add(A2)) raises(DDMShapeError, lambda: A2.add(A1)) Az = DomainMatrix([[ZZ(1), ZZ(2)], [ZZ(3), ZZ(4)]], (2, 2), ZZ) Aq = DomainMatrix([[QQ(1), QQ(2)], [QQ(3), QQ(4)]], (2, 2), QQ) Asum = DomainMatrix([[QQ(2), QQ(4)], [QQ(6), QQ(8)]], (2, 2), QQ) assert Az + Aq == Asum assert Aq + Az == Asum raises(DDMDomainError, lambda: Az.add(Aq)) raises(DDMDomainError, lambda: Aq.add(Az)) As = DomainMatrix({0: {1: ZZ(1)}, 1: {0: ZZ(2)}}, (2, 2), ZZ) Ad = DomainMatrix([[ZZ(1), ZZ(2)], [ZZ(3), ZZ(4)]], (2, 2), ZZ) Asd = As + Ad Ads = Ad + As assert Asd == DomainMatrix([[1, 3], [5, 4]], (2, 2), ZZ) assert Asd.rep == DDM([[1, 3], [5, 4]], (2, 2), ZZ) assert Ads == DomainMatrix([[1, 3], [5, 4]], (2, 2), ZZ) assert Ads.rep == DDM([[1, 3], [5, 4]], (2, 2), ZZ) raises(DDMFormatError, lambda: As.add(Ad)) def test_DomainMatrix_sub(): A = DomainMatrix([[ZZ(1), ZZ(2)], [ZZ(3), ZZ(4)]], (2, 2), ZZ) B = DomainMatrix([[ZZ(0), ZZ(0)], [ZZ(0), ZZ(0)]], (2, 2), ZZ) assert A - A == A.sub(A) == B A = DomainMatrix([[ZZ(1), ZZ(2)], [ZZ(3), ZZ(4)]], (2, 2), ZZ) L = [[2, 3], [3, 4]] raises(TypeError, lambda: A - L) raises(TypeError, lambda: L - A) A1 = DomainMatrix([[ZZ(1), ZZ(2)], [ZZ(3), ZZ(4)]], (2, 2), ZZ) A2 = DomainMatrix([[ZZ(1), ZZ(2)]], (1, 2), ZZ) raises(DDMShapeError, lambda: A1 - A2) raises(DDMShapeError, lambda: A2 - A1) raises(DDMShapeError, lambda: A1.sub(A2)) raises(DDMShapeError, lambda: A2.sub(A1)) Az = DomainMatrix([[ZZ(1), ZZ(2)], [ZZ(3), ZZ(4)]], (2, 2), ZZ) Aq = DomainMatrix([[QQ(1), QQ(2)], [QQ(3), QQ(4)]], (2, 2), QQ) Adiff = DomainMatrix([[QQ(0), QQ(0)], [QQ(0), QQ(0)]], (2, 2), QQ) assert Az - Aq == Adiff assert Aq - Az == Adiff raises(DDMDomainError, lambda: Az.sub(Aq)) raises(DDMDomainError, lambda: Aq.sub(Az)) As = DomainMatrix({0: {1: ZZ(1)}, 1: {0: ZZ(2)}}, (2, 2), ZZ) Ad = DomainMatrix([[ZZ(1), ZZ(2)], [ZZ(3), ZZ(4)]], (2, 2), ZZ) Asd = As - Ad Ads = Ad - As assert Asd == DomainMatrix([[-1, -1], [-1, -4]], (2, 2), ZZ) assert Asd.rep == DDM([[-1, -1], [-1, -4]], (2, 2), ZZ) assert Asd == -Ads assert Asd.rep == -Ads.rep def test_DomainMatrix_neg(): A = DomainMatrix([[ZZ(1), ZZ(2)], [ZZ(3), ZZ(4)]], (2, 2), ZZ) Aneg = DomainMatrix([[ZZ(-1), ZZ(-2)], [ZZ(-3), ZZ(-4)]], (2, 2), ZZ) assert -A == A.neg() == Aneg def test_DomainMatrix_mul(): A = DomainMatrix([[ZZ(1), ZZ(2)], [ZZ(3), ZZ(4)]], (2, 2), ZZ) A2 = DomainMatrix([[ZZ(7), ZZ(10)], [ZZ(15), ZZ(22)]], (2, 2), ZZ) assert A*A == A.matmul(A) == A2 A = DomainMatrix([[ZZ(1), ZZ(2)], [ZZ(3), ZZ(4)]], (2, 2), ZZ) L = [[1, 2], [3, 4]] raises(TypeError, lambda: A * L) raises(TypeError, lambda: L * A) Az = DomainMatrix([[ZZ(1), ZZ(2)], [ZZ(3), ZZ(4)]], (2, 2), ZZ) Aq = DomainMatrix([[QQ(1), QQ(2)], [QQ(3), QQ(4)]], (2, 2), QQ) Aprod = DomainMatrix([[QQ(7), QQ(10)], [QQ(15), QQ(22)]], (2, 2), QQ) assert Az * Aq == Aprod assert Aq * Az == Aprod raises(DDMDomainError, lambda: Az.matmul(Aq)) raises(DDMDomainError, lambda: Aq.matmul(Az)) A = DomainMatrix([[ZZ(1), ZZ(2)], [ZZ(3), ZZ(4)]], (2, 2), ZZ) AA = DomainMatrix([[ZZ(2), ZZ(4)], [ZZ(6), ZZ(8)]], (2, 2), ZZ) x = ZZ(2) assert A * x == x * A == A.mul(x) == AA A = DomainMatrix([[ZZ(1), ZZ(2)], [ZZ(3), ZZ(4)]], (2, 2), ZZ) AA = DomainMatrix([[ZZ(0), ZZ(0)], [ZZ(0), ZZ(0)]], (2, 2), ZZ) x = ZZ(0) assert A * x == x * A == A.mul(x) == AA As = DomainMatrix({0: {1: ZZ(1)}, 1: {0: ZZ(2)}}, (2, 2), ZZ) Ad = DomainMatrix([[ZZ(1), ZZ(2)], [ZZ(3), ZZ(4)]], (2, 2), ZZ) Asd = As * Ad Ads = Ad * As assert Asd == DomainMatrix([[3, 4], [2, 4]], (2, 2), ZZ) assert Asd.rep == DDM([[3, 4], [2, 4]], (2, 2), ZZ) assert Ads == DomainMatrix([[4, 1], [8, 3]], (2, 2), ZZ) assert Ads.rep == DDM([[4, 1], [8, 3]], (2, 2), ZZ) def test_DomainMatrix_pow(): eye = DomainMatrix.eye(2, ZZ) A = DomainMatrix([[ZZ(1), ZZ(2)], [ZZ(3), ZZ(4)]], (2, 2), ZZ) A2 = DomainMatrix([[ZZ(7), ZZ(10)], [ZZ(15), ZZ(22)]], (2, 2), ZZ) A3 = DomainMatrix([[ZZ(37), ZZ(54)], [ZZ(81), ZZ(118)]], (2, 2), ZZ) assert A**0 == A.pow(0) == eye assert A**1 == A.pow(1) == A assert A**2 == A.pow(2) == A2 assert A**3 == A.pow(3) == A3 raises(TypeError, lambda: A ** Rational(1, 2)) raises(NotImplementedError, lambda: A ** -1) raises(NotImplementedError, lambda: A.pow(-1)) A = DomainMatrix.zeros((2, 1), ZZ) raises(NonSquareMatrixError, lambda: A ** 1) def test_DomainMatrix_rref(): A = DomainMatrix([], (0, 1), QQ) assert A.rref() == (A, ()) A = DomainMatrix([[QQ(1)]], (1, 1), QQ) assert A.rref() == (A, (0,)) A = DomainMatrix([[QQ(0)]], (1, 1), QQ) assert A.rref() == (A, ()) A = DomainMatrix([[QQ(1), QQ(2)], [QQ(3), QQ(4)]], (2, 2), QQ) Ar, pivots = A.rref() assert Ar == DomainMatrix([[QQ(1), QQ(0)], [QQ(0), QQ(1)]], (2, 2), QQ) assert pivots == (0, 1) A = DomainMatrix([[QQ(0), QQ(2)], [QQ(3), QQ(4)]], (2, 2), QQ) Ar, pivots = A.rref() assert Ar == DomainMatrix([[QQ(1), QQ(0)], [QQ(0), QQ(1)]], (2, 2), QQ) assert pivots == (0, 1) A = DomainMatrix([[QQ(0), QQ(2)], [QQ(0), QQ(4)]], (2, 2), QQ) Ar, pivots = A.rref() assert Ar == DomainMatrix([[QQ(0), QQ(1)], [QQ(0), QQ(0)]], (2, 2), QQ) assert pivots == (1,) Az = DomainMatrix([[ZZ(1), ZZ(2)], [ZZ(3), ZZ(4)]], (2, 2), ZZ) raises(ValueError, lambda: Az.rref()) def test_DomainMatrix_nullspace(): A = DomainMatrix([[QQ(1), QQ(1)], [QQ(1), QQ(1)]], (2, 2), QQ) Anull = DomainMatrix([[QQ(-1), QQ(1)]], (1, 2), QQ) assert A.nullspace() == Anull Az = DomainMatrix([[ZZ(1), ZZ(1)], [ZZ(1), ZZ(1)]], (2, 2), ZZ) raises(ValueError, lambda: Az.nullspace()) def test_DomainMatrix_solve(): # XXX: Maybe the _solve method should be changed... A = DomainMatrix([[QQ(1), QQ(2)], [QQ(2), QQ(4)]], (2, 2), QQ) b = DomainMatrix([[QQ(1)], [QQ(2)]], (2, 1), QQ) particular = DomainMatrix([[1, 0]], (1, 2), QQ) nullspace = DomainMatrix([[-2, 1]], (1, 2), QQ) assert A._solve(b) == (particular, nullspace) b3 = DomainMatrix([[QQ(1)], [QQ(1)], [QQ(1)]], (3, 1), QQ) raises(ShapeError, lambda: A._solve(b3)) bz = DomainMatrix([[ZZ(1)], [ZZ(1)]], (2, 1), ZZ) raises(ValueError, lambda: A._solve(bz)) def test_DomainMatrix_inv(): A = DomainMatrix([], (0, 0), QQ) assert A.inv() == A A = DomainMatrix([[QQ(1), QQ(2)], [QQ(3), QQ(4)]], (2, 2), QQ) Ainv = DomainMatrix([[QQ(-2), QQ(1)], [QQ(3, 2), QQ(-1, 2)]], (2, 2), QQ) assert A.inv() == Ainv Az = DomainMatrix([[ZZ(1), ZZ(2)], [ZZ(3), ZZ(4)]], (2, 2), ZZ) raises(ValueError, lambda: Az.inv()) Ans = DomainMatrix([[QQ(1), QQ(2)]], (1, 2), QQ) raises(NonSquareMatrixError, lambda: Ans.inv()) Aninv = DomainMatrix([[QQ(1), QQ(2)], [QQ(3), QQ(6)]], (2, 2), QQ) raises(NonInvertibleMatrixError, lambda: Aninv.inv()) def test_DomainMatrix_det(): A = DomainMatrix([], (0, 0), ZZ) assert A.det() == 1 A = DomainMatrix([[1]], (1, 1), ZZ) assert A.det() == 1 A = DomainMatrix([[ZZ(1), ZZ(2)], [ZZ(3), ZZ(4)]], (2, 2), ZZ) assert A.det() == ZZ(-2) A = DomainMatrix([[ZZ(1), ZZ(2), ZZ(3)], [ZZ(1), ZZ(2), ZZ(4)], [ZZ(1), ZZ(3), ZZ(5)]], (3, 3), ZZ) assert A.det() == ZZ(-1) A = DomainMatrix([[ZZ(1), ZZ(2), ZZ(3)], [ZZ(1), ZZ(2), ZZ(4)], [ZZ(1), ZZ(2), ZZ(5)]], (3, 3), ZZ) assert A.det() == ZZ(0) Ans = DomainMatrix([[QQ(1), QQ(2)]], (1, 2), QQ) raises(NonSquareMatrixError, lambda: Ans.det()) A = DomainMatrix([[QQ(1), QQ(2)], [QQ(3), QQ(4)]], (2, 2), QQ) assert A.det() == QQ(-2) def test_DomainMatrix_lu(): A = DomainMatrix([], (0, 0), QQ) assert A.lu() == (A, A, []) A = DomainMatrix([[QQ(1), QQ(2)], [QQ(3), QQ(4)]], (2, 2), QQ) L = DomainMatrix([[QQ(1), QQ(0)], [QQ(3), QQ(1)]], (2, 2), QQ) U = DomainMatrix([[QQ(1), QQ(2)], [QQ(0), QQ(-2)]], (2, 2), QQ) swaps = [] assert A.lu() == (L, U, swaps) A = DomainMatrix([[QQ(0), QQ(2)], [QQ(3), QQ(4)]], (2, 2), QQ) L = DomainMatrix([[QQ(1), QQ(0)], [QQ(0), QQ(1)]], (2, 2), QQ) U = DomainMatrix([[QQ(3), QQ(4)], [QQ(0), QQ(2)]], (2, 2), QQ) swaps = [(0, 1)] assert A.lu() == (L, U, swaps) A = DomainMatrix([[QQ(1), QQ(2)], [QQ(2), QQ(4)]], (2, 2), QQ) L = DomainMatrix([[QQ(1), QQ(0)], [QQ(2), QQ(1)]], (2, 2), QQ) U = DomainMatrix([[QQ(1), QQ(2)], [QQ(0), QQ(0)]], (2, 2), QQ) swaps = [] assert A.lu() == (L, U, swaps) A = DomainMatrix([[QQ(0), QQ(2)], [QQ(0), QQ(4)]], (2, 2), QQ) L = DomainMatrix([[QQ(1), QQ(0)], [QQ(0), QQ(1)]], (2, 2), QQ) U = DomainMatrix([[QQ(0), QQ(2)], [QQ(0), QQ(4)]], (2, 2), QQ) swaps = [] assert A.lu() == (L, U, swaps) A = DomainMatrix([[QQ(1), QQ(2), QQ(3)], [QQ(4), QQ(5), QQ(6)]], (2, 3), QQ) L = DomainMatrix([[QQ(1), QQ(0)], [QQ(4), QQ(1)]], (2, 2), QQ) U = DomainMatrix([[QQ(1), QQ(2), QQ(3)], [QQ(0), QQ(-3), QQ(-6)]], (2, 3), QQ) swaps = [] assert A.lu() == (L, U, swaps) A = DomainMatrix([[QQ(1), QQ(2)], [QQ(3), QQ(4)], [QQ(5), QQ(6)]], (3, 2), QQ) L = DomainMatrix([ [QQ(1), QQ(0), QQ(0)], [QQ(3), QQ(1), QQ(0)], [QQ(5), QQ(2), QQ(1)]], (3, 3), QQ) U = DomainMatrix([[QQ(1), QQ(2)], [QQ(0), QQ(-2)], [QQ(0), QQ(0)]], (3, 2), QQ) swaps = [] assert A.lu() == (L, U, swaps) A = [[1, 0, 0, 0], [0, 0, 0, 0], [0, 0, 1, 1], [0, 0, 1, 2]] L = [[1, 0, 0, 0], [0, 1, 0, 0], [0, 0, 1, 0], [0, 0, 1, 1]] U = [[1, 0, 0, 0], [0, 0, 0, 0], [0, 0, 1, 1], [0, 0, 0, 1]] to_dom = lambda rows, dom: [[dom(e) for e in row] for row in rows] A = DomainMatrix(to_dom(A, QQ), (4, 4), QQ) L = DomainMatrix(to_dom(L, QQ), (4, 4), QQ) U = DomainMatrix(to_dom(U, QQ), (4, 4), QQ) assert A.lu() == (L, U, []) A = DomainMatrix([[ZZ(1), ZZ(2)], [ZZ(3), ZZ(4)]], (2, 2), ZZ) raises(ValueError, lambda: A.lu()) def test_DomainMatrix_lu_solve(): # Base case A = b = x = DomainMatrix([], (0, 0), QQ) assert A.lu_solve(b) == x # Basic example A = DomainMatrix([[QQ(1), QQ(2)], [QQ(3), QQ(4)]], (2, 2), QQ) b = DomainMatrix([[QQ(1)], [QQ(2)]], (2, 1), QQ) x = DomainMatrix([[QQ(0)], [QQ(1, 2)]], (2, 1), QQ) assert A.lu_solve(b) == x # Example with swaps A = DomainMatrix([[QQ(0), QQ(2)], [QQ(3), QQ(4)]], (2, 2), QQ) b = DomainMatrix([[QQ(1)], [QQ(2)]], (2, 1), QQ) x = DomainMatrix([[QQ(0)], [QQ(1, 2)]], (2, 1), QQ) assert A.lu_solve(b) == x # Non-invertible A = DomainMatrix([[QQ(1), QQ(2)], [QQ(2), QQ(4)]], (2, 2), QQ) b = DomainMatrix([[QQ(1)], [QQ(2)]], (2, 1), QQ) raises(NonInvertibleMatrixError, lambda: A.lu_solve(b)) # Overdetermined, consistent A = DomainMatrix([[QQ(1), QQ(2)], [QQ(3), QQ(4)], [QQ(5), QQ(6)]], (3, 2), QQ) b = DomainMatrix([[QQ(1)], [QQ(2)], [QQ(3)]], (3, 1), QQ) x = DomainMatrix([[QQ(0)], [QQ(1, 2)]], (2, 1), QQ) assert A.lu_solve(b) == x # Overdetermined, inconsistent A = DomainMatrix([[QQ(1), QQ(2)], [QQ(3), QQ(4)], [QQ(5), QQ(6)]], (3, 2), QQ) b = DomainMatrix([[QQ(1)], [QQ(2)], [QQ(4)]], (3, 1), QQ) raises(NonInvertibleMatrixError, lambda: A.lu_solve(b)) # Underdetermined A = DomainMatrix([[QQ(1), QQ(2)]], (1, 2), QQ) b = DomainMatrix([[QQ(1)]], (1, 1), QQ) raises(NotImplementedError, lambda: A.lu_solve(b)) # Non-field A = DomainMatrix([[ZZ(1), ZZ(2)], [ZZ(3), ZZ(4)]], (2, 2), ZZ) b = DomainMatrix([[ZZ(1)], [ZZ(2)]], (2, 1), ZZ) raises(ValueError, lambda: A.lu_solve(b)) # Shape mismatch A = DomainMatrix([[QQ(1), QQ(2)], [QQ(3), QQ(4)]], (2, 2), QQ) b = DomainMatrix([[QQ(1), QQ(2)]], (1, 2), QQ) raises(ShapeError, lambda: A.lu_solve(b)) def test_DomainMatrix_charpoly(): A = DomainMatrix([], (0, 0), ZZ) assert A.charpoly() == [ZZ(1)] A = DomainMatrix([[1]], (1, 1), ZZ) assert A.charpoly() == [ZZ(1), ZZ(-1)] A = DomainMatrix([[ZZ(1), ZZ(2)], [ZZ(3), ZZ(4)]], (2, 2), ZZ) assert A.charpoly() == [ZZ(1), ZZ(-5), ZZ(-2)] A = DomainMatrix([[ZZ(1), ZZ(2), ZZ(3)], [ZZ(4), ZZ(5), ZZ(6)], [ZZ(7), ZZ(8), ZZ(9)]], (3, 3), ZZ) assert A.charpoly() == [ZZ(1), ZZ(-15), ZZ(-18), ZZ(0)] Ans = DomainMatrix([[QQ(1), QQ(2)]], (1, 2), QQ) raises(NonSquareMatrixError, lambda: Ans.charpoly()) def test_DomainMatrix_eye(): A = DomainMatrix.eye(3, QQ) assert A.rep == SDM.eye(3, QQ) assert A.shape == (3, 3) assert A.domain == QQ def test_DomainMatrix_zeros(): A = DomainMatrix.zeros((1, 2), QQ) assert A.rep == SDM.zeros((1, 2), QQ) assert A.shape == (1, 2) assert A.domain == QQ def test_DomainMatrix_ones(): A = DomainMatrix.ones((2, 3), QQ) assert A.rep == DDM.ones((2, 3), QQ) assert A.shape == (2, 3) assert A.domain == QQ def test_DomainMatrix_diag(): A = DomainMatrix({0:{0:ZZ(2)}, 1:{1:ZZ(3)}}, (2, 2), ZZ) assert DomainMatrix.diag([ZZ(2), ZZ(3)], ZZ) == A A = DomainMatrix({0:{0:ZZ(2)}, 1:{1:ZZ(3)}}, (3, 4), ZZ) assert DomainMatrix.diag([ZZ(2), ZZ(3)], ZZ, (3, 4)) == A def test_DomainMatrix_hstack(): A = DomainMatrix([[ZZ(1)], [ZZ(2)]], (2, 1), ZZ) B = DomainMatrix([[QQ(3), QQ(4)], [QQ(5), QQ(6)]], (2, 2), QQ) AB = DomainMatrix([[QQ(1), QQ(3), QQ(4)], [QQ(2), QQ(5), QQ(6)]], (2, 3), QQ) assert A.hstack(B) == AB def test_DomainMatrix_vstack(): A = DomainMatrix([[ZZ(1), ZZ(2)]], (1, 2), ZZ) B = DomainMatrix([[QQ(3), QQ(4)], [QQ(5), QQ(6)]], (2, 2), QQ) AB = DomainMatrix([[QQ(1), QQ(2)], [QQ(3), QQ(4)], [QQ(5), QQ(6)]], (3, 2), QQ) assert A.vstack(B) == AB def test_DomainMatrix_applyfunc(): A = DomainMatrix([[ZZ(1), ZZ(2)]], (1, 2), ZZ) B = DomainMatrix([[ZZ(2), ZZ(4)]], (1, 2), ZZ) assert A.applyfunc(lambda x: 2*x) == B def test_DomainMatrix_scalarmul(): A = DomainMatrix([[ZZ(1), ZZ(2)], [ZZ(3), ZZ(4)]], (2, 2), ZZ) lamda = DomainScalar(QQ(3)/QQ(2), QQ) assert A * lamda == DomainMatrix([[QQ(3, 2), QQ(3)], [QQ(9, 2), QQ(6)]], (2, 2), QQ) assert A * 2 == DomainMatrix([[ZZ(2), ZZ(4)], [ZZ(6), ZZ(8)]], (2, 2), ZZ) assert A * DomainScalar(ZZ(0), ZZ) == DomainMatrix([[ZZ(0)]*2]*2, (2, 2), ZZ) assert A * DomainScalar(ZZ(1), ZZ) == A raises(TypeError, lambda: A * 1.5) def test_DomainMatrix_truediv(): A = DomainMatrix.from_Matrix(Matrix([[1, 2], [3, 4]])) lamda = DomainScalar(QQ(3)/QQ(2), QQ) assert A / lamda == DomainMatrix({0: {0: QQ(2, 3), 1: QQ(4, 3)}, 1: {0: QQ(2), 1: QQ(8, 3)}}, (2, 2), QQ) b = DomainScalar(ZZ(1), ZZ) assert A / b == DomainMatrix({0: {0: QQ(1), 1: QQ(2)}, 1: {0: QQ(3), 1: QQ(4)}}, (2, 2), QQ) assert A / 1 == DomainMatrix({0: {0: QQ(1), 1: QQ(2)}, 1: {0: QQ(3), 1: QQ(4)}}, (2, 2), QQ) assert A / 2 == DomainMatrix({0: {0: QQ(1, 2), 1: QQ(1)}, 1: {0: QQ(3, 2), 1: QQ(2)}}, (2, 2), QQ) raises(ZeroDivisionError, lambda: A / 0) raises(TypeError, lambda: A / 1.5) raises(ZeroDivisionError, lambda: A / DomainScalar(ZZ(0), ZZ)) def test_DomainMatrix_getitem(): dM = DomainMatrix([ [ZZ(1), ZZ(2), ZZ(3)], [ZZ(4), ZZ(5), ZZ(6)], [ZZ(7), ZZ(8), ZZ(9)]], (3, 3), ZZ) assert dM[1:,:-2] == DomainMatrix([[ZZ(4)], [ZZ(7)]], (2, 1), ZZ) assert dM[2,:-2] == DomainMatrix([[ZZ(7)]], (1, 1), ZZ) assert dM[:-2,:-2] == DomainMatrix([[ZZ(1)]], (1, 1), ZZ) assert dM[:-1,0:2] == DomainMatrix([[ZZ(1), ZZ(2)], [ZZ(4), ZZ(5)]], (2, 2), ZZ) assert dM[:, -1] == DomainMatrix([[ZZ(3)], [ZZ(6)], [ZZ(9)]], (3, 1), ZZ) assert dM[-1, :] == DomainMatrix([[ZZ(7), ZZ(8), ZZ(9)]], (1, 3), ZZ) assert dM[::-1, :] == DomainMatrix([ [ZZ(7), ZZ(8), ZZ(9)], [ZZ(4), ZZ(5), ZZ(6)], [ZZ(1), ZZ(2), ZZ(3)]], (3, 3), ZZ) raises(IndexError, lambda: dM[4, :-2]) raises(IndexError, lambda: dM[:-2, 4]) assert dM[1, 2] == DomainScalar(ZZ(6), ZZ) assert dM[-2, 2] == DomainScalar(ZZ(6), ZZ) assert dM[1, -2] == DomainScalar(ZZ(5), ZZ) assert dM[-1, -3] == DomainScalar(ZZ(7), ZZ) raises(IndexError, lambda: dM[3, 3]) raises(IndexError, lambda: dM[1, 4]) raises(IndexError, lambda: dM[-1, -4]) dM = DomainMatrix({0: {0: ZZ(1)}}, (10, 10), ZZ) assert dM[5, 5] == DomainScalar(ZZ(0), ZZ) assert dM[0, 0] == DomainScalar(ZZ(1), ZZ) dM = DomainMatrix({1: {0: 1}}, (2,1), ZZ) assert dM[0:, 0] == DomainMatrix({1: {0: 1}}, (2, 1), ZZ) raises(IndexError, lambda: dM[3, 0]) dM = DomainMatrix({2: {2: ZZ(1)}, 4: {4: ZZ(1)}}, (5, 5), ZZ) assert dM[:2,:2] == DomainMatrix({}, (2, 2), ZZ) assert dM[2:,2:] == DomainMatrix({0: {0: 1}, 2: {2: 1}}, (3, 3), ZZ) assert dM[3:,3:] == DomainMatrix({1: {1: 1}}, (2, 2), ZZ) assert dM[2:, 6:] == DomainMatrix({}, (3, 0), ZZ)
713b44b35f6b1b98dcef845dbfff40d7a52e61a48ee359ad30ccae8dac3a1a27
# # test_linsolve.py # # Test the internal implementation of linsolve. # from sympy.testing.pytest import raises from sympy import S, Eq, I from sympy.abc import x, y, z from sympy.polys.matrices.linsolve import _linsolve from sympy.polys.solvers import PolyNonlinearError def test__linsolve(): assert _linsolve([], [x]) == {x:x} assert _linsolve([S.Zero], [x]) == {x:x} assert _linsolve([x-1,x-2], [x]) is None assert _linsolve([x-1], [x]) == {x:1} assert _linsolve([x-1, y], [x, y]) == {x:1, y:S.Zero} assert _linsolve([2*I], [x]) is None raises(PolyNonlinearError, lambda: _linsolve([x*(1 + x)], [x])) def test__linsolve_float(): # This should give the exact answer: eqs = [ y - x, y - 0.0216 * x ] sol = {x:0.0, y:0.0} assert _linsolve(eqs, (x, y)) == sol # Other cases should be close to eps def all_close(sol1, sol2, eps=1e-15): close = lambda a, b: abs(a - b) < eps assert sol1.keys() == sol2.keys() return all(close(sol1[s], sol2[s]) for s in sol1) eqs = [ 0.8*x + 0.8*z + 0.2, 0.9*x + 0.7*y + 0.2*z + 0.9, 0.7*x + 0.2*y + 0.2*z + 0.5 ] sol_exact = {x:-29/42, y:-11/21, z:37/84} sol_linsolve = _linsolve(eqs, [x,y,z]) assert all_close(sol_exact, sol_linsolve) eqs = [ 0.9*x + 0.3*y + 0.4*z + 0.6, 0.6*x + 0.9*y + 0.1*z + 0.7, 0.4*x + 0.6*y + 0.9*z + 0.5 ] sol_exact = {x:-88/175, y:-46/105, z:-1/25} sol_linsolve = _linsolve(eqs, [x,y,z]) assert all_close(sol_exact, sol_linsolve) eqs = [ 0.4*x + 0.3*y + 0.6*z + 0.7, 0.4*x + 0.3*y + 0.9*z + 0.9, 0.7*x + 0.9*y, ] sol_exact = {x:-9/5, y:7/5, z:-2/3} sol_linsolve = _linsolve(eqs, [x,y,z]) assert all_close(sol_exact, sol_linsolve) eqs = [ x*(0.7 + 0.6*I) + y*(0.4 + 0.7*I) + z*(0.9 + 0.1*I) + 0.5, 0.2*I*x + 0.2*I*y + z*(0.9 + 0.2*I) + 0.1, x*(0.9 + 0.7*I) + y*(0.9 + 0.7*I) + z*(0.9 + 0.4*I) + 0.4, ] sol_exact = { x:-6157/7995 - 411/5330*I, y:8519/15990 + 1784/7995*I, z:-34/533 + 107/1599*I, } sol_linsolve = _linsolve(eqs, [x,y,z]) assert all_close(sol_exact, sol_linsolve) # XXX: This system for x and y over RR(z) is problematic. # # eqs = [ # x*(0.2*z + 0.9) + y*(0.5*z + 0.8) + 0.6, # 0.1*x*z + y*(0.1*z + 0.6) + 0.9, # ] # # linsolve(eqs, [x, y]) # The solution for x comes out as # # -3.9e-5*z**2 - 3.6e-5*z - 8.67361737988404e-20 # x = ---------------------------------------------- # 3.0e-6*z**3 - 1.3e-5*z**2 - 5.4e-5*z # # The 8e-20 in the numerator should be zero which would allow z to cancel # from top and bottom. It should be possible to avoid this somehow because # the inverse of the matrix only has a quadratic factor (the determinant) # in the denominator. def test__linsolve_deprecated(): assert _linsolve([Eq(x**2, x**2+y)], [x, y]) == {x:x, y:S.Zero} assert _linsolve([(x+y)**2-x**2], [x]) == {x:-y/2} assert _linsolve([Eq((x+y)**2, x**2)], [x]) == {x:-y/2}
3f710408ba8ba713fbb98d434d1958985ba00bac5bff17cade32760cd8b0ef79
from sympy.testing.pytest import raises from sympy.polys import ZZ, QQ from sympy.polys.matrices.ddm import DDM from sympy.polys.matrices.dense import ( ddm_transpose, ddm_iadd, ddm_isub, ddm_ineg, ddm_imatmul, ddm_imul, ddm_irref, ddm_idet, ddm_iinv, ddm_ilu, ddm_ilu_split, ddm_ilu_solve, ddm_berk) from sympy.polys.matrices.exceptions import ( DDMShapeError, NonInvertibleMatrixError, NonSquareMatrixError) def test_ddm_transpose(): a = [[1, 2], [3, 4]] assert ddm_transpose(a) == [[1, 3], [2, 4]] def test_ddm_iadd(): a = [[1, 2], [3, 4]] b = [[5, 6], [7, 8]] ddm_iadd(a, b) assert a == [[6, 8], [10, 12]] def test_ddm_isub(): a = [[1, 2], [3, 4]] b = [[5, 6], [7, 8]] ddm_isub(a, b) assert a == [[-4, -4], [-4, -4]] def test_ddm_ineg(): a = [[1, 2], [3, 4]] ddm_ineg(a) assert a == [[-1, -2], [-3, -4]] def test_ddm_matmul(): a = [[1, 2], [3, 4]] ddm_imul(a, 2) assert a == [[2, 4], [6, 8]] a = [[1, 2], [3, 4]] ddm_imul(a, 0) assert a == [[0, 0], [0, 0]] def test_ddm_imatmul(): a = [[1, 2, 3], [4, 5, 6]] b = [[1, 2], [3, 4], [5, 6]] c1 = [[0, 0], [0, 0]] ddm_imatmul(c1, a, b) assert c1 == [[22, 28], [49, 64]] c2 = [[0, 0, 0], [0, 0, 0], [0, 0, 0]] ddm_imatmul(c2, b, a) assert c2 == [[9, 12, 15], [19, 26, 33], [29, 40, 51]] b3 = [[1], [2], [3]] c3 = [[0], [0]] ddm_imatmul(c3, a, b3) assert c3 == [[14], [32]] def test_ddm_irref(): # Empty matrix A = [] Ar = [] pivots = [] assert ddm_irref(A) == pivots assert A == Ar # Standard square case A = [[QQ(0), QQ(1)], [QQ(1), QQ(1)]] Ar = [[QQ(1), QQ(0)], [QQ(0), QQ(1)]] pivots = [0, 1] assert ddm_irref(A) == pivots assert A == Ar # m < n case A = [[QQ(1), QQ(2), QQ(1)], [QQ(3), QQ(4), QQ(1)]] Ar = [[QQ(1), QQ(0), QQ(-1)], [QQ(0), QQ(1), QQ(1)]] pivots = [0, 1] assert ddm_irref(A) == pivots assert A == Ar # same m < n but reversed A = [[QQ(3), QQ(4), QQ(1)], [QQ(1), QQ(2), QQ(1)]] Ar = [[QQ(1), QQ(0), QQ(-1)], [QQ(0), QQ(1), QQ(1)]] pivots = [0, 1] assert ddm_irref(A) == pivots assert A == Ar # m > n case A = [[QQ(1), QQ(0)], [QQ(1), QQ(3)], [QQ(0), QQ(1)]] Ar = [[QQ(1), QQ(0)], [QQ(0), QQ(1)], [QQ(0), QQ(0)]] pivots = [0, 1] assert ddm_irref(A) == pivots assert A == Ar # Example with missing pivot A = [[QQ(1), QQ(0), QQ(1)], [QQ(3), QQ(0), QQ(1)]] Ar = [[QQ(1), QQ(0), QQ(0)], [QQ(0), QQ(0), QQ(1)]] pivots = [0, 2] assert ddm_irref(A) == pivots assert A == Ar # Example with missing pivot and no replacement A = [[QQ(0), QQ(1)], [QQ(0), QQ(2)], [QQ(1), QQ(0)]] Ar = [[QQ(1), QQ(0)], [QQ(0), QQ(1)], [QQ(0), QQ(0)]] pivots = [0, 1] assert ddm_irref(A) == pivots assert A == Ar def test_ddm_idet(): A = [] assert ddm_idet(A, ZZ) == ZZ(1) A = [[ZZ(2)]] assert ddm_idet(A, ZZ) == ZZ(2) A = [[ZZ(1), ZZ(2)], [ZZ(3), ZZ(4)]] assert ddm_idet(A, ZZ) == ZZ(-2) A = [[ZZ(1), ZZ(2), ZZ(3)], [ZZ(1), ZZ(2), ZZ(4)], [ZZ(1), ZZ(3), ZZ(5)]] assert ddm_idet(A, ZZ) == ZZ(-1) A = [[ZZ(1), ZZ(2), ZZ(3)], [ZZ(1), ZZ(2), ZZ(4)], [ZZ(1), ZZ(2), ZZ(5)]] assert ddm_idet(A, ZZ) == ZZ(0) A = [[QQ(1, 2), QQ(1, 2)], [QQ(1, 3), QQ(1, 4)]] assert ddm_idet(A, QQ) == QQ(-1, 24) def test_ddm_inv(): A = [] Ainv = [] ddm_iinv(Ainv, A, QQ) assert Ainv == A A = [] Ainv = [] raises(ValueError, lambda: ddm_iinv(Ainv, A, ZZ)) A = [[QQ(1), QQ(2)]] Ainv = [[QQ(0), QQ(0)]] raises(NonSquareMatrixError, lambda: ddm_iinv(Ainv, A, QQ)) A = [[QQ(1, 1), QQ(2, 1)], [QQ(3, 1), QQ(4, 1)]] Ainv = [[QQ(0), QQ(0)], [QQ(0), QQ(0)]] Ainv_expected = [[QQ(-2, 1), QQ(1, 1)], [QQ(3, 2), QQ(-1, 2)]] ddm_iinv(Ainv, A, QQ) assert Ainv == Ainv_expected A = [[QQ(1, 1), QQ(2, 1)], [QQ(2, 1), QQ(4, 1)]] Ainv = [[QQ(0), QQ(0)], [QQ(0), QQ(0)]] raises(NonInvertibleMatrixError, lambda: ddm_iinv(Ainv, A, QQ)) def test_ddm_ilu(): A = [] Alu = [] swaps = ddm_ilu(A) assert A == Alu assert swaps == [] A = [[]] Alu = [[]] swaps = ddm_ilu(A) assert A == Alu assert swaps == [] A = [[QQ(1), QQ(2)], [QQ(3), QQ(4)]] Alu = [[QQ(1), QQ(2)], [QQ(3), QQ(-2)]] swaps = ddm_ilu(A) assert A == Alu assert swaps == [] A = [[QQ(0), QQ(2)], [QQ(3), QQ(4)]] Alu = [[QQ(3), QQ(4)], [QQ(0), QQ(2)]] swaps = ddm_ilu(A) assert A == Alu assert swaps == [(0, 1)] A = [[QQ(1), QQ(2), QQ(3)], [QQ(4), QQ(5), QQ(6)], [QQ(7), QQ(8), QQ(9)]] Alu = [[QQ(1), QQ(2), QQ(3)], [QQ(4), QQ(-3), QQ(-6)], [QQ(7), QQ(2), QQ(0)]] swaps = ddm_ilu(A) assert A == Alu assert swaps == [] A = [[QQ(0), QQ(1), QQ(2)], [QQ(0), QQ(1), QQ(3)], [QQ(1), QQ(1), QQ(2)]] Alu = [[QQ(1), QQ(1), QQ(2)], [QQ(0), QQ(1), QQ(3)], [QQ(0), QQ(1), QQ(-1)]] swaps = ddm_ilu(A) assert A == Alu assert swaps == [(0, 2)] A = [[QQ(1), QQ(2), QQ(3)], [QQ(4), QQ(5), QQ(6)]] Alu = [[QQ(1), QQ(2), QQ(3)], [QQ(4), QQ(-3), QQ(-6)]] swaps = ddm_ilu(A) assert A == Alu assert swaps == [] A = [[QQ(1), QQ(2)], [QQ(3), QQ(4)], [QQ(5), QQ(6)]] Alu = [[QQ(1), QQ(2)], [QQ(3), QQ(-2)], [QQ(5), QQ(2)]] swaps = ddm_ilu(A) assert A == Alu assert swaps == [] def test_ddm_ilu_split(): U = [] L = [] Uexp = [] Lexp = [] swaps = ddm_ilu_split(L, U, QQ) assert U == Uexp assert L == Lexp assert swaps == [] U = [[]] L = [[QQ(1)]] Uexp = [[]] Lexp = [[QQ(1)]] swaps = ddm_ilu_split(L, U, QQ) assert U == Uexp assert L == Lexp assert swaps == [] U = [[QQ(1), QQ(2)], [QQ(3), QQ(4)]] L = [[QQ(1), QQ(0)], [QQ(0), QQ(1)]] Uexp = [[QQ(1), QQ(2)], [QQ(0), QQ(-2)]] Lexp = [[QQ(1), QQ(0)], [QQ(3), QQ(1)]] swaps = ddm_ilu_split(L, U, QQ) assert U == Uexp assert L == Lexp assert swaps == [] U = [[QQ(1), QQ(2), QQ(3)], [QQ(4), QQ(5), QQ(6)]] L = [[QQ(1), QQ(0)], [QQ(0), QQ(1)]] Uexp = [[QQ(1), QQ(2), QQ(3)], [QQ(0), QQ(-3), QQ(-6)]] Lexp = [[QQ(1), QQ(0)], [QQ(4), QQ(1)]] swaps = ddm_ilu_split(L, U, QQ) assert U == Uexp assert L == Lexp assert swaps == [] U = [[QQ(1), QQ(2)], [QQ(3), QQ(4)], [QQ(5), QQ(6)]] L = [[QQ(1), QQ(0), QQ(0)], [QQ(0), QQ(1), QQ(0)], [QQ(0), QQ(0), QQ(1)]] Uexp = [[QQ(1), QQ(2)], [QQ(0), QQ(-2)], [QQ(0), QQ(0)]] Lexp = [[QQ(1), QQ(0), QQ(0)], [QQ(3), QQ(1), QQ(0)], [QQ(5), QQ(2), QQ(1)]] swaps = ddm_ilu_split(L, U, QQ) assert U == Uexp assert L == Lexp assert swaps == [] def test_ddm_ilu_solve(): # Basic example # A = [[QQ(1), QQ(2)], [QQ(3), QQ(4)]] U = [[QQ(1), QQ(2)], [QQ(0), QQ(-2)]] L = [[QQ(1), QQ(0)], [QQ(3), QQ(1)]] swaps = [] b = DDM([[QQ(1)], [QQ(2)]], (2, 1), QQ) x = DDM([[QQ(0)], [QQ(0)]], (2, 1), QQ) xexp = DDM([[QQ(0)], [QQ(1, 2)]], (2, 1), QQ) ddm_ilu_solve(x, L, U, swaps, b) assert x == xexp # Example with swaps # A = [[QQ(0), QQ(2)], [QQ(3), QQ(4)]] U = [[QQ(3), QQ(4)], [QQ(0), QQ(2)]] L = [[QQ(1), QQ(0)], [QQ(0), QQ(1)]] swaps = [(0, 1)] b = DDM([[QQ(1)], [QQ(2)]], (2, 1), QQ) x = DDM([[QQ(0)], [QQ(0)]], (2, 1), QQ) xexp = DDM([[QQ(0)], [QQ(1, 2)]], (2, 1), QQ) ddm_ilu_solve(x, L, U, swaps, b) assert x == xexp # Overdetermined, consistent # A = DDM([[QQ(1), QQ(2)], [QQ(3), QQ(4)], [QQ(5), QQ(6)]], (3, 2), QQ) U = [[QQ(1), QQ(2)], [QQ(0), QQ(-2)], [QQ(0), QQ(0)]] L = [[QQ(1), QQ(0), QQ(0)], [QQ(3), QQ(1), QQ(0)], [QQ(5), QQ(2), QQ(1)]] swaps = [] b = DDM([[QQ(1)], [QQ(2)], [QQ(3)]], (3, 1), QQ) x = DDM([[QQ(0)], [QQ(0)]], (2, 1), QQ) xexp = DDM([[QQ(0)], [QQ(1, 2)]], (2, 1), QQ) ddm_ilu_solve(x, L, U, swaps, b) assert x == xexp # Overdetermined, inconsistent b = DDM([[QQ(1)], [QQ(2)], [QQ(4)]], (3, 1), QQ) raises(NonInvertibleMatrixError, lambda: ddm_ilu_solve(x, L, U, swaps, b)) # Square, noninvertible # A = DDM([[QQ(1), QQ(2)], [QQ(1), QQ(2)]], (2, 2), QQ) U = [[QQ(1), QQ(2)], [QQ(0), QQ(0)]] L = [[QQ(1), QQ(0)], [QQ(1), QQ(1)]] swaps = [] b = DDM([[QQ(1)], [QQ(2)]], (2, 1), QQ) raises(NonInvertibleMatrixError, lambda: ddm_ilu_solve(x, L, U, swaps, b)) # Underdetermined # A = DDM([[QQ(1), QQ(2)]], (1, 2), QQ) U = [[QQ(1), QQ(2)]] L = [[QQ(1)]] swaps = [] b = DDM([[QQ(3)]], (1, 1), QQ) raises(NotImplementedError, lambda: ddm_ilu_solve(x, L, U, swaps, b)) # Shape mismatch b3 = DDM([[QQ(1)], [QQ(2)], [QQ(3)]], (3, 1), QQ) raises(DDMShapeError, lambda: ddm_ilu_solve(x, L, U, swaps, b3)) # Empty shape mismatch U = [[QQ(1)]] L = [[QQ(1)]] swaps = [] x = [[QQ(1)]] b = [] raises(DDMShapeError, lambda: ddm_ilu_solve(x, L, U, swaps, b)) # Empty system U = [] L = [] swaps = [] b = [] x = [] ddm_ilu_solve(x, L, U, swaps, b) assert x == [] def test_ddm_charpoly(): A = [] assert ddm_berk(A, ZZ) == [[ZZ(1)]] A = [[ZZ(1), ZZ(2), ZZ(3)], [ZZ(4), ZZ(5), ZZ(6)], [ZZ(7), ZZ(8), ZZ(9)]] Avec = [[ZZ(1)], [ZZ(-15)], [ZZ(-18)], [ZZ(0)]] assert ddm_berk(A, ZZ) == Avec A = DDM([[ZZ(1), ZZ(2)]], (1, 2), ZZ) raises(DDMShapeError, lambda: ddm_berk(A, ZZ))
ee43c5e1bf1b68d6c58936ddd4e1bbdf2b6e2386706b15de94dea1833cd60b7c
""" Tests for the basic functionality of the SDM class. """ from sympy.core.compatibility import HAS_GMPY from sympy.testing.pytest import raises from sympy import QQ, ZZ from sympy.polys.matrices.sdm import SDM from sympy.polys.matrices.ddm import DDM from sympy.polys.matrices.exceptions import (DDMBadInputError, DDMDomainError, DDMShapeError) def test_SDM(): A = SDM({0:{0:ZZ(1)}}, (2, 2), ZZ) assert A.domain == ZZ assert A.shape == (2, 2) assert dict(A) == {0:{0:ZZ(1)}} raises(DDMBadInputError, lambda: SDM({5:{1:ZZ(0)}}, (2, 2), ZZ)) raises(DDMBadInputError, lambda: SDM({0:{5:ZZ(0)}}, (2, 2), ZZ)) def test_DDM_str(): sdm = SDM({0:{0:ZZ(1)}, 1:{1:ZZ(1)}}, (2, 2), ZZ) assert str(sdm) == '{0: {0: 1}, 1: {1: 1}}' if HAS_GMPY: # pragma: no cover assert repr(sdm) == 'SDM({0: {0: mpz(1)}, 1: {1: mpz(1)}}, (2, 2), ZZ)' else: # pragma: no cover assert repr(sdm) == 'SDM({0: {0: 1}, 1: {1: 1}}, (2, 2), ZZ)' def test_SDM_new(): A = SDM({0:{0:ZZ(1)}}, (2, 2), ZZ) B = A.new({}, (2, 2), ZZ) assert B == SDM({}, (2, 2), ZZ) def test_SDM_copy(): A = SDM({0:{0:ZZ(1)}}, (2, 2), ZZ) B = A.copy() assert A == B A[0][0] = ZZ(2) assert A != B def test_SDM_from_list(): A = SDM.from_list([[ZZ(0), ZZ(1)], [ZZ(1), ZZ(0)]], (2, 2), ZZ) assert A == SDM({0:{1:ZZ(1)}, 1:{0:ZZ(1)}}, (2, 2), ZZ) raises(DDMBadInputError, lambda: SDM.from_list([[ZZ(0)], [ZZ(0), ZZ(1)]], (2, 2), ZZ)) raises(DDMBadInputError, lambda: SDM.from_list([[ZZ(0), ZZ(1)]], (2, 2), ZZ)) def test_SDM_to_list(): A = SDM({0:{1: ZZ(1)}}, (2, 2), ZZ) assert A.to_list() == [[ZZ(0), ZZ(1)], [ZZ(0), ZZ(0)]] A = SDM({}, (0, 2), ZZ) assert A.to_list() == [] A = SDM({}, (2, 0), ZZ) assert A.to_list() == [[], []] def test_SDM_from_ddm(): A = DDM([[ZZ(1), ZZ(0)], [ZZ(1), ZZ(0)]], (2, 2), ZZ) B = SDM.from_ddm(A) assert B.domain == ZZ assert B.shape == (2, 2) assert dict(B) == {0:{0:ZZ(1)}, 1:{0:ZZ(1)}} def test_SDM_to_ddm(): A = SDM({0:{1: ZZ(1)}}, (2, 2), ZZ) B = DDM([[ZZ(0), ZZ(1)], [ZZ(0), ZZ(0)]], (2, 2), ZZ) assert A.to_ddm() == B def test_SDM_zeros(): A = SDM.zeros((2, 2), ZZ) assert A.domain == ZZ assert A.shape == (2, 2) assert dict(A) == {} def test_SDM_ones(): A = SDM.ones((1, 2), QQ) assert A.domain == QQ assert A.shape == (1, 2) assert dict(A) == {0:{0:QQ(1), 1:QQ(1)}} def test_SDM_eye(): A = SDM.eye(2, ZZ) assert A.domain == ZZ assert A.shape == (2, 2) assert dict(A) == {0:{0:ZZ(1)}, 1:{1:ZZ(1)}} def test_SDM_transpose(): A = SDM({0:{0:ZZ(1), 1:ZZ(2)}, 1:{0:ZZ(3), 1:ZZ(4)}}, (2, 2), ZZ) B = SDM({0:{0:ZZ(1), 1:ZZ(3)}, 1:{0:ZZ(2), 1:ZZ(4)}}, (2, 2), ZZ) assert A.transpose() == B A = SDM({0:{1:ZZ(2)}}, (2, 2), ZZ) B = SDM({1:{0:ZZ(2)}}, (2, 2), ZZ) assert A.transpose() == B A = SDM({0:{1:ZZ(2)}}, (1, 2), ZZ) B = SDM({1:{0:ZZ(2)}}, (2, 1), ZZ) assert A.transpose() == B def test_SDM_mul(): A = SDM({0:{0:ZZ(2)}}, (2, 2), ZZ) B = SDM({0:{0:ZZ(4)}}, (2, 2), ZZ) assert A*ZZ(2) == B assert ZZ(2)*A == B raises(TypeError, lambda: A*QQ(1, 2)) raises(TypeError, lambda: QQ(1, 2)*A) def test_SDM_matmul(): A = SDM({0:{0:ZZ(2)}}, (2, 2), ZZ) B = SDM({0:{0:ZZ(4)}}, (2, 2), ZZ) assert A.matmul(A) == A*A == B C = SDM({0:{0:ZZ(2)}}, (2, 2), QQ) raises(DDMDomainError, lambda: A.matmul(C)) A = SDM({0:{0:ZZ(1), 1:ZZ(2)}, 1:{0:ZZ(3), 1:ZZ(4)}}, (2, 2), ZZ) B = SDM({0:{0:ZZ(7), 1:ZZ(10)}, 1:{0:ZZ(15), 1:ZZ(22)}}, (2, 2), ZZ) assert A.matmul(A) == A*A == B A22 = SDM({0:{0:ZZ(4)}}, (2, 2), ZZ) A32 = SDM({0:{0:ZZ(2)}}, (3, 2), ZZ) A23 = SDM({0:{0:ZZ(4)}}, (2, 3), ZZ) A33 = SDM({0:{0:ZZ(8)}}, (3, 3), ZZ) A22 = SDM({0:{0:ZZ(8)}}, (2, 2), ZZ) assert A32.matmul(A23) == A33 assert A23.matmul(A32) == A22 # XXX: @ not supported by SDM... #assert A32.matmul(A23) == A32 @ A23 == A33 #assert A23.matmul(A32) == A23 @ A32 == A22 #raises(DDMShapeError, lambda: A23 @ A22) raises(DDMShapeError, lambda: A23.matmul(A22)) A = SDM({0: {0: ZZ(-1), 1: ZZ(1)}}, (1, 2), ZZ) B = SDM({0: {0: ZZ(-1)}, 1: {0: ZZ(-1)}}, (2, 1), ZZ) assert A.matmul(B) == A*B == SDM({}, (1, 1), ZZ) def test_SDM_add(): A = SDM({0:{1:ZZ(1)}, 1:{0:ZZ(2), 1:ZZ(3)}}, (2, 2), ZZ) B = SDM({0:{0:ZZ(1)}, 1:{0:ZZ(-2), 1:ZZ(3)}}, (2, 2), ZZ) C = SDM({0:{0:ZZ(1), 1:ZZ(1)}, 1:{1:ZZ(6)}}, (2, 2), ZZ) assert A.add(B) == B.add(A) == A + B == B + A == C A = SDM({0:{1:ZZ(1)}}, (2, 2), ZZ) B = SDM({0:{0:ZZ(1)}, 1:{0:ZZ(-2), 1:ZZ(3)}}, (2, 2), ZZ) C = SDM({0:{0:ZZ(1), 1:ZZ(1)}, 1:{0:ZZ(-2), 1:ZZ(3)}}, (2, 2), ZZ) assert A.add(B) == B.add(A) == A + B == B + A == C raises(TypeError, lambda: A + []) def test_SDM_sub(): A = SDM({0:{1:ZZ(1)}, 1:{0:ZZ(2), 1:ZZ(3)}}, (2, 2), ZZ) B = SDM({0:{0:ZZ(1)}, 1:{0:ZZ(-2), 1:ZZ(3)}}, (2, 2), ZZ) C = SDM({0:{0:ZZ(-1), 1:ZZ(1)}, 1:{0:ZZ(4)}}, (2, 2), ZZ) assert A.sub(B) == A - B == C raises(TypeError, lambda: A - []) def test_SDM_neg(): A = SDM({0:{1:ZZ(1)}, 1:{0:ZZ(2), 1:ZZ(3)}}, (2, 2), ZZ) B = SDM({0:{1:ZZ(-1)}, 1:{0:ZZ(-2), 1:ZZ(-3)}}, (2, 2), ZZ) assert A.neg() == -A == B def test_SDM_convert_to(): A = SDM({0:{1:ZZ(1)}, 1:{0:ZZ(2), 1:ZZ(3)}}, (2, 2), ZZ) B = SDM({0:{1:QQ(1)}, 1:{0:QQ(2), 1:QQ(3)}}, (2, 2), QQ) C = A.convert_to(QQ) assert C == B assert C.domain == QQ D = A.convert_to(ZZ) assert D == A assert D.domain == ZZ def test_SDM_hstack(): A = SDM({0:{1:ZZ(1)}}, (2, 2), ZZ) B = SDM({1:{1:ZZ(1)}}, (2, 2), ZZ) AA = SDM({0:{1:ZZ(1), 3:ZZ(1)}}, (2, 4), ZZ) AB = SDM({0:{1:ZZ(1)}, 1:{3:ZZ(1)}}, (2, 4), ZZ) assert SDM.hstack(A) == A assert SDM.hstack(A, A) == AA assert SDM.hstack(A, B) == AB def test_SDM_vstack(): A = SDM({0:{1:ZZ(1)}}, (2, 2), ZZ) B = SDM({1:{1:ZZ(1)}}, (2, 2), ZZ) AA = SDM({0:{1:ZZ(1)}, 2:{1:ZZ(1)}}, (4, 2), ZZ) AB = SDM({0:{1:ZZ(1)}, 3:{1:ZZ(1)}}, (4, 2), ZZ) assert SDM.vstack(A) == A assert SDM.vstack(A, A) == AA assert SDM.vstack(A, B) == AB def test_SDM_applyfunc(): A = SDM({0:{1:ZZ(1)}}, (2, 2), ZZ) B = SDM({0:{1:ZZ(2)}}, (2, 2), ZZ) assert A.applyfunc(lambda x: 2*x, ZZ) == B def test_SDM_inv(): A = SDM({0:{0:QQ(1), 1:QQ(2)}, 1:{0:QQ(3), 1:QQ(4)}}, (2, 2), QQ) B = SDM({0:{0:QQ(-2), 1:QQ(1)}, 1:{0:QQ(3, 2), 1:QQ(-1, 2)}}, (2, 2), QQ) assert A.inv() == B def test_SDM_det(): A = SDM({0:{0:QQ(1), 1:QQ(2)}, 1:{0:QQ(3), 1:QQ(4)}}, (2, 2), QQ) assert A.det() == QQ(-2) def test_SDM_lu(): A = SDM({0:{0:QQ(1), 1:QQ(2)}, 1:{0:QQ(3), 1:QQ(4)}}, (2, 2), QQ) L = SDM({0:{0:QQ(1)}, 1:{0:QQ(3), 1:QQ(1)}}, (2, 2), QQ) #U = SDM({0:{0:QQ(1), 1:QQ(2)}, 1:{0:QQ(3), 1:QQ(-2)}}, (2, 2), QQ) #swaps = [] # This doesn't quite work. U has some nonzero elements in the lower part. #assert A.lu() == (L, U, swaps) assert A.lu()[0] == L def test_SDM_lu_solve(): A = SDM({0:{0:QQ(1), 1:QQ(2)}, 1:{0:QQ(3), 1:QQ(4)}}, (2, 2), QQ) b = SDM({0:{0:QQ(1)}, 1:{0:QQ(2)}}, (2, 1), QQ) x = SDM({1:{0:QQ(1, 2)}}, (2, 1), QQ) assert A.matmul(x) == b assert A.lu_solve(b) == x def test_SDM_charpoly(): A = SDM({0:{0:ZZ(1), 1:ZZ(2)}, 1:{0:ZZ(3), 1:ZZ(4)}}, (2, 2), ZZ) assert A.charpoly() == [ZZ(1), ZZ(-5), ZZ(-2)] def test_SDM_nullspace(): A = SDM({0:{0:QQ(1), 1:QQ(1)}}, (2, 2), QQ) assert A.nullspace()[0] == SDM({0:{0:QQ(-1), 1:QQ(1)}}, (1, 2), QQ) def test_SDM_rref(): eye2 = SDM({0:{0:QQ(1)}, 1:{1:QQ(1)}}, (2, 2), QQ) A = SDM({0:{0:QQ(1), 1:QQ(2)}, 1:{0:QQ(3), 1:QQ(4)}}, (2, 2), QQ) assert A.rref() == (eye2, [0, 1]) A = SDM({0:{0:QQ(1)}, 1:{0:QQ(3), 1:QQ(4)}}, (2, 2), QQ) assert A.rref() == (eye2, [0, 1]) A = SDM({0:{1:QQ(2)}, 1:{0:QQ(3), 1:QQ(4)}}, (2, 2), QQ) assert A.rref() == (eye2, [0, 1]) A = SDM({0:{0:QQ(1), 1:QQ(2), 2:QQ(3)}, 1:{0:QQ(4), 1:QQ(5), 2:QQ(6)}, 2:{0:QQ(7), 1:QQ(8), 2:QQ(9)} }, (3, 3), QQ) Arref = SDM({0:{0:QQ(1), 2:QQ(-1)}, 1:{1:QQ(1), 2:QQ(2)}}, (3, 3), QQ) assert A.rref() == (Arref, [0, 1]) A = SDM({0:{0:QQ(1), 1:QQ(2), 3:QQ(1)}, 1:{0:QQ(1), 1:QQ(1), 2:QQ(9)}}, (2, 4), QQ) Arref = SDM({0:{0:QQ(1), 2:QQ(18), 3:QQ(-1)}, 1:{1:QQ(1), 2:QQ(-9), 3:QQ(1)}}, (2, 4), QQ) assert A.rref() == (Arref, [0, 1]) A = SDM({0:{0:QQ(1), 1:QQ(1), 2:QQ(1)}, 1:{0:QQ(1), 1:QQ(2), 2:QQ(2)}}, (2, 3), QQ) Arref = SDM( {0: {0: QQ(1,1)}, 1: {1: QQ(1,1), 2: QQ(1,1)}}, (2, 3), QQ) assert A.rref() == (Arref, [0, 1]) def test_SDM_particular(): A = SDM({0:{0:QQ(1)}}, (2, 2), QQ) Apart = SDM.zeros((1, 2), QQ) assert A.particular() == Apart
80925dd76c779c242ab6d691bf59a74b00643bc20fdfb7d05c6f15201b2c31af
# -*- coding: utf-8 -*- import sys from sympy.assumptions import Q from sympy.core import Symbol, Function, Float, Rational, Integer, I, Mul, Pow, Eq from sympy.functions import exp, factorial, factorial2, sin from sympy.logic import And from sympy.series import Limit from sympy.testing.pytest import raises, skip from sympy.parsing.sympy_parser import ( parse_expr, standard_transformations, rationalize, TokenError, split_symbols, implicit_multiplication, convert_equals_signs, convert_xor, function_exponentiation, implicit_multiplication_application, ) def test_sympy_parser(): x = Symbol('x') inputs = { '2*x': 2 * x, '3.00': Float(3), '22/7': Rational(22, 7), '2+3j': 2 + 3*I, 'exp(x)': exp(x), 'x!': factorial(x), 'x!!': factorial2(x), '(x + 1)! - 1': factorial(x + 1) - 1, '3.[3]': Rational(10, 3), '.0[3]': Rational(1, 30), '3.2[3]': Rational(97, 30), '1.3[12]': Rational(433, 330), '1 + 3.[3]': Rational(13, 3), '1 + .0[3]': Rational(31, 30), '1 + 3.2[3]': Rational(127, 30), '.[0011]': Rational(1, 909), '0.1[00102] + 1': Rational(366697, 333330), '1.[0191]': Rational(10190, 9999), '10!': 3628800, '-(2)': -Integer(2), '[-1, -2, 3]': [Integer(-1), Integer(-2), Integer(3)], 'Symbol("x").free_symbols': x.free_symbols, "S('S(3).n(n=3)')": 3.00, 'factorint(12, visual=True)': Mul( Pow(2, 2, evaluate=False), Pow(3, 1, evaluate=False), evaluate=False), 'Limit(sin(x), x, 0, dir="-")': Limit(sin(x), x, 0, dir='-'), 'Q.even(x)': Q.even(x), } for text, result in inputs.items(): assert parse_expr(text) == result raises(TypeError, lambda: parse_expr('x', standard_transformations)) raises(TypeError, lambda: parse_expr('x', transformations=lambda x,y: 1)) raises(TypeError, lambda: parse_expr('x', transformations=(lambda x,y: 1,))) raises(TypeError, lambda: parse_expr('x', transformations=((),))) raises(TypeError, lambda: parse_expr('x', {}, [], [])) raises(TypeError, lambda: parse_expr('x', [], [], {})) raises(TypeError, lambda: parse_expr('x', [], [], {})) def test_rationalize(): inputs = { '0.123': Rational(123, 1000) } transformations = standard_transformations + (rationalize,) for text, result in inputs.items(): assert parse_expr(text, transformations=transformations) == result def test_factorial_fail(): inputs = ['x!!!', 'x!!!!', '(!)'] for text in inputs: try: parse_expr(text) assert False except TokenError: assert True def test_repeated_fail(): inputs = ['1[1]', '.1e1[1]', '0x1[1]', '1.1j[1]', '1.1[1 + 1]', '0.1[[1]]', '0x1.1[1]'] # All are valid Python, so only raise TypeError for invalid indexing for text in inputs: raises(TypeError, lambda: parse_expr(text)) inputs = ['0.1[', '0.1[1', '0.1[]'] for text in inputs: raises((TokenError, SyntaxError), lambda: parse_expr(text)) def test_repeated_dot_only(): assert parse_expr('.[1]') == Rational(1, 9) assert parse_expr('1 + .[1]') == Rational(10, 9) def test_local_dict(): local_dict = { 'my_function': lambda x: x + 2 } inputs = { 'my_function(2)': Integer(4) } for text, result in inputs.items(): assert parse_expr(text, local_dict=local_dict) == result def test_local_dict_split_implmult(): t = standard_transformations + (split_symbols, implicit_multiplication,) w = Symbol('w', real=True) y = Symbol('y') assert parse_expr('yx', local_dict={'x':w}, transformations=t) == y*w def test_local_dict_symbol_to_fcn(): x = Symbol('x') d = {'foo': Function('bar')} assert parse_expr('foo(x)', local_dict=d) == d['foo'](x) d = {'foo': Symbol('baz')} raises(TypeError, lambda: parse_expr('foo(x)', local_dict=d)) def test_global_dict(): global_dict = { 'Symbol': Symbol } inputs = { 'Q & S': And(Symbol('Q'), Symbol('S')) } for text, result in inputs.items(): assert parse_expr(text, global_dict=global_dict) == result def test_issue_2515(): raises(TokenError, lambda: parse_expr('(()')) raises(TokenError, lambda: parse_expr('"""')) def test_issue_7663(): x = Symbol('x') e = '2*(x+1)' assert parse_expr(e, evaluate=0) == parse_expr(e, evaluate=False) assert parse_expr(e, evaluate=0).equals(2*(x+1)) def test_recursive_evaluate_false_10560(): inputs = { '4*-3' : '4*-3', '-4*3' : '(-4)*3', "-2*x*y": '(-2)*x*y', "x*-4*x": "x*(-4)*x" } for text, result in inputs.items(): assert parse_expr(text, evaluate=False) == parse_expr(result, evaluate=False) def test_issue_10773(): inputs = { '-10/5': '(-10)/5', '-10/-5' : '(-10)/(-5)', } for text, result in inputs.items(): assert parse_expr(text, evaluate=False) == parse_expr(result, evaluate=False) def test_split_symbols(): transformations = standard_transformations + \ (split_symbols, implicit_multiplication,) x = Symbol('x') y = Symbol('y') xy = Symbol('xy') assert parse_expr("xy") == xy assert parse_expr("xy", transformations=transformations) == x*y def test_split_symbols_function(): transformations = standard_transformations + \ (split_symbols, implicit_multiplication,) x = Symbol('x') y = Symbol('y') a = Symbol('a') f = Function('f') assert parse_expr("ay(x+1)", transformations=transformations) == a*y*(x+1) assert parse_expr("af(x+1)", transformations=transformations, local_dict={'f':f}) == a*f(x+1) def test_functional_exponent(): t = standard_transformations + (convert_xor, function_exponentiation) x = Symbol('x') y = Symbol('y') a = Symbol('a') yfcn = Function('y') assert parse_expr("sin^2(x)", transformations=t) == (sin(x))**2 assert parse_expr("sin^y(x)", transformations=t) == (sin(x))**y assert parse_expr("exp^y(x)", transformations=t) == (exp(x))**y assert parse_expr("E^y(x)", transformations=t) == exp(yfcn(x)) assert parse_expr("a^y(x)", transformations=t) == a**(yfcn(x)) def test_match_parentheses_implicit_multiplication(): transformations = standard_transformations + \ (implicit_multiplication,) raises(TokenError, lambda: parse_expr('(1,2),(3,4]',transformations=transformations)) def test_convert_equals_signs(): transformations = standard_transformations + \ (convert_equals_signs, ) x = Symbol('x') y = Symbol('y') assert parse_expr("1*2=x", transformations=transformations) == Eq(2, x) assert parse_expr("y = x", transformations=transformations) == Eq(y, x) assert parse_expr("(2*y = x) = False", transformations=transformations) == Eq(Eq(2*y, x), False) def test_parse_function_issue_3539(): x = Symbol('x') f = Function('f') assert parse_expr('f(x)') == f(x) def test_split_symbols_numeric(): transformations = ( standard_transformations + (implicit_multiplication_application,)) n = Symbol('n') expr1 = parse_expr('2**n * 3**n') expr2 = parse_expr('2**n3**n', transformations=transformations) assert expr1 == expr2 == 2**n*3**n expr1 = parse_expr('n12n34', transformations=transformations) assert expr1 == n*12*n*34 def test_unicode_names(): assert parse_expr('α') == Symbol('α') def test_python3_features(): # Make sure the tokenizer can handle Python 3-only features if sys.version_info < (3, 6): skip("test_python3_features requires Python 3.6 or newer") assert parse_expr("123_456") == 123456 assert parse_expr("1.2[3_4]") == parse_expr("1.2[34]") == Rational(611, 495) assert parse_expr("1.2[012_012]") == parse_expr("1.2[012012]") == Rational(400, 333) assert parse_expr('.[3_4]') == parse_expr('.[34]') == Rational(34, 99) assert parse_expr('.1[3_4]') == parse_expr('.1[34]') == Rational(133, 990) assert parse_expr('123_123.123_123[3_4]') == parse_expr('123123.123123[34]') == Rational(12189189189211, 99000000) def test_issue_19501(): x = Symbol('x') eq = parse_expr('E**x(1+x)', local_dict={'x': x}, transformations=( standard_transformations + (implicit_multiplication_application,))) assert eq.free_symbols == {x}
0176c6c255f3dd9057a43f6b000c601a62c0b395feb0e8bba0434d77d8573990
from sympy.testing.pytest import raises, XFAIL from sympy.external import import_module from sympy import ( Symbol, Mul, Add, Abs, sin, asin, cos, Pow, csc, sec, Limit, oo, Derivative, Integral, factorial, sqrt, root, conjugate, StrictLessThan, LessThan, StrictGreaterThan, GreaterThan, Sum, Product, E, log, tan, Function, binomial, exp, floor, ceiling, Unequality ) from sympy.core.relational import Eq, Ne, Lt, Le, Gt, Ge from sympy.physics.quantum.state import Bra, Ket from sympy.abc import x, y, z, a, b, c, t, k, n antlr4 = import_module("antlr4") # disable tests if antlr4-python*-runtime is not present if not antlr4: disabled = True theta = Symbol('theta') f = Function('f') # shorthand definitions def _Add(a, b): return Add(a, b, evaluate=False) def _Mul(a, b): return Mul(a, b, evaluate=False) def _Pow(a, b): return Pow(a, b, evaluate=False) def _Sqrt(a): return sqrt(a, evaluate=False) def _Conjugate(a): return conjugate(a, evaluate=False) def _Abs(a): return Abs(a, evaluate=False) def _factorial(a): return factorial(a, evaluate=False) def _exp(a): return exp(a, evaluate=False) def _log(a, b): return log(a, b, evaluate=False) def _binomial(n, k): return binomial(n, k, evaluate=False) def test_import(): from sympy.parsing.latex._build_latex_antlr import ( build_parser, check_antlr_version, dir_latex_antlr ) # XXX: It would be better to come up with a test for these... del build_parser, check_antlr_version, dir_latex_antlr # These LaTeX strings should parse to the corresponding SymPy expression GOOD_PAIRS = [ (r"0", 0), (r"1", 1), (r"-3.14", -3.14), (r"(-7.13)(1.5)", _Mul(-7.13, 1.5)), (r"x", x), (r"2x", 2*x), (r"x^2", x**2), (r"x^{3 + 1}", x**_Add(3, 1)), (r"-c", -c), (r"a \cdot b", a * b), (r"a / b", a / b), (r"a \div b", a / b), (r"a + b", a + b), (r"a + b - a", _Add(a+b, -a)), (r"a^2 + b^2 = c^2", Eq(a**2 + b**2, c**2)), (r"(x + y) z", _Mul(_Add(x, y), z)), (r"\left(x + y\right) z", _Mul(_Add(x, y), z)), (r"\left( x + y\right ) z", _Mul(_Add(x, y), z)), (r"\left( x + y\right ) z", _Mul(_Add(x, y), z)), (r"\left[x + y\right] z", _Mul(_Add(x, y), z)), (r"\left\{x + y\right\} z", _Mul(_Add(x, y), z)), (r"1+1", _Add(1, 1)), (r"0+1", _Add(0, 1)), (r"1*2", _Mul(1, 2)), (r"0*1", _Mul(0, 1)), (r"x = y", Eq(x, y)), (r"x \neq y", Ne(x, y)), (r"x < y", Lt(x, y)), (r"x > y", Gt(x, y)), (r"x \leq y", Le(x, y)), (r"x \geq y", Ge(x, y)), (r"x \le y", Le(x, y)), (r"x \ge y", Ge(x, y)), (r"\lfloor x \rfloor", floor(x)), (r"\lceil x \rceil", ceiling(x)), (r"\langle x |", Bra('x')), (r"| x \rangle", Ket('x')), (r"\sin \theta", sin(theta)), (r"\sin(\theta)", sin(theta)), (r"\sin^{-1} a", asin(a)), (r"\sin a \cos b", _Mul(sin(a), cos(b))), (r"\sin \cos \theta", sin(cos(theta))), (r"\sin(\cos \theta)", sin(cos(theta))), (r"\frac{a}{b}", a / b), (r"\frac{a + b}{c}", _Mul(a + b, _Pow(c, -1))), (r"\frac{7}{3}", _Mul(7, _Pow(3, -1))), (r"(\csc x)(\sec y)", csc(x)*sec(y)), (r"\lim_{x \to 3} a", Limit(a, x, 3)), (r"\lim_{x \rightarrow 3} a", Limit(a, x, 3)), (r"\lim_{x \Rightarrow 3} a", Limit(a, x, 3)), (r"\lim_{x \longrightarrow 3} a", Limit(a, x, 3)), (r"\lim_{x \Longrightarrow 3} a", Limit(a, x, 3)), (r"\lim_{x \to 3^{+}} a", Limit(a, x, 3, dir='+')), (r"\lim_{x \to 3^{-}} a", Limit(a, x, 3, dir='-')), (r"\infty", oo), (r"\lim_{x \to \infty} \frac{1}{x}", Limit(_Pow(x, -1), x, oo)), (r"\frac{d}{dx} x", Derivative(x, x)), (r"\frac{d}{dt} x", Derivative(x, t)), (r"f(x)", f(x)), (r"f(x, y)", f(x, y)), (r"f(x, y, z)", f(x, y, z)), (r"\frac{d f(x)}{dx}", Derivative(f(x), x)), (r"\frac{d\theta(x)}{dx}", Derivative(Function('theta')(x), x)), (r"x \neq y", Unequality(x, y)), (r"|x|", _Abs(x)), (r"||x||", _Abs(Abs(x))), (r"|x||y|", _Abs(x)*_Abs(y)), (r"||x||y||", _Abs(_Abs(x)*_Abs(y))), (r"\pi^{|xy|}", Symbol('pi')**_Abs(x*y)), (r"\int x dx", Integral(x, x)), (r"\int x d\theta", Integral(x, theta)), (r"\int (x^2 - y)dx", Integral(x**2 - y, x)), (r"\int x + a dx", Integral(_Add(x, a), x)), (r"\int da", Integral(1, a)), (r"\int_0^7 dx", Integral(1, (x, 0, 7))), (r"\int_a^b x dx", Integral(x, (x, a, b))), (r"\int^b_a x dx", Integral(x, (x, a, b))), (r"\int_{a}^b x dx", Integral(x, (x, a, b))), (r"\int^{b}_a x dx", Integral(x, (x, a, b))), (r"\int_{a}^{b} x dx", Integral(x, (x, a, b))), (r"\int^{b}_{a} x dx", Integral(x, (x, a, b))), (r"\int_{f(a)}^{f(b)} f(z) dz", Integral(f(z), (z, f(a), f(b)))), (r"\int (x+a)", Integral(_Add(x, a), x)), (r"\int a + b + c dx", Integral(_Add(_Add(a, b), c), x)), (r"\int \frac{dz}{z}", Integral(Pow(z, -1), z)), (r"\int \frac{3 dz}{z}", Integral(3*Pow(z, -1), z)), (r"\int \frac{1}{x} dx", Integral(Pow(x, -1), x)), (r"\int \frac{1}{a} + \frac{1}{b} dx", Integral(_Add(_Pow(a, -1), Pow(b, -1)), x)), (r"\int \frac{3 \cdot d\theta}{\theta}", Integral(3*_Pow(theta, -1), theta)), (r"\int \frac{1}{x} + 1 dx", Integral(_Add(_Pow(x, -1), 1), x)), (r"x_0", Symbol('x_{0}')), (r"x_{1}", Symbol('x_{1}')), (r"x_a", Symbol('x_{a}')), (r"x_{b}", Symbol('x_{b}')), (r"h_\theta", Symbol('h_{theta}')), (r"h_{\theta}", Symbol('h_{theta}')), (r"h_{\theta}(x_0, x_1)", Function('h_{theta}')(Symbol('x_{0}'), Symbol('x_{1}'))), (r"x!", _factorial(x)), (r"100!", _factorial(100)), (r"\theta!", _factorial(theta)), (r"(x + 1)!", _factorial(_Add(x, 1))), (r"(x!)!", _factorial(_factorial(x))), (r"x!!!", _factorial(_factorial(_factorial(x)))), (r"5!7!", _Mul(_factorial(5), _factorial(7))), (r"\sqrt{x}", sqrt(x)), (r"\sqrt{x + b}", sqrt(_Add(x, b))), (r"\sqrt[3]{\sin x}", root(sin(x), 3)), (r"\sqrt[y]{\sin x}", root(sin(x), y)), (r"\sqrt[\theta]{\sin x}", root(sin(x), theta)), (r"\sqrt{\frac{12}{6}}", _Sqrt(_Mul(12, _Pow(6, -1)))), (r"\overline{z}", _Conjugate(z)), (r"\overline{\overline{z}}", _Conjugate(_Conjugate(z))), (r"\overline{x + y}", _Conjugate(_Add(x, y))), (r"\overline{x} + \overline{y}", _Conjugate(x) + _Conjugate(y)), (r"x < y", StrictLessThan(x, y)), (r"x \leq y", LessThan(x, y)), (r"x > y", StrictGreaterThan(x, y)), (r"x \geq y", GreaterThan(x, y)), (r"\mathit{x}", Symbol('x')), (r"\mathit{test}", Symbol('test')), (r"\mathit{TEST}", Symbol('TEST')), (r"\mathit{HELLO world}", Symbol('HELLO world')), (r"\sum_{k = 1}^{3} c", Sum(c, (k, 1, 3))), (r"\sum_{k = 1}^3 c", Sum(c, (k, 1, 3))), (r"\sum^{3}_{k = 1} c", Sum(c, (k, 1, 3))), (r"\sum^3_{k = 1} c", Sum(c, (k, 1, 3))), (r"\sum_{k = 1}^{10} k^2", Sum(k**2, (k, 1, 10))), (r"\sum_{n = 0}^{\infty} \frac{1}{n!}", Sum(_Pow(_factorial(n), -1), (n, 0, oo))), (r"\prod_{a = b}^{c} x", Product(x, (a, b, c))), (r"\prod_{a = b}^c x", Product(x, (a, b, c))), (r"\prod^{c}_{a = b} x", Product(x, (a, b, c))), (r"\prod^c_{a = b} x", Product(x, (a, b, c))), (r"\exp x", _exp(x)), (r"\exp(x)", _exp(x)), (r"\ln x", _log(x, E)), (r"\ln xy", _log(x*y, E)), (r"\log x", _log(x, 10)), (r"\log xy", _log(x*y, 10)), (r"\log_{2} x", _log(x, 2)), (r"\log_{a} x", _log(x, a)), (r"\log_{11} x", _log(x, 11)), (r"\log_{a^2} x", _log(x, _Pow(a, 2))), (r"[x]", x), (r"[a + b]", _Add(a, b)), (r"\frac{d}{dx} [ \tan x ]", Derivative(tan(x), x)), (r"\binom{n}{k}", _binomial(n, k)), (r"\tbinom{n}{k}", _binomial(n, k)), (r"\dbinom{n}{k}", _binomial(n, k)), (r"\binom{n}{0}", _binomial(n, 0)), (r"a \, b", _Mul(a, b)), (r"a \thinspace b", _Mul(a, b)), (r"a \: b", _Mul(a, b)), (r"a \medspace b", _Mul(a, b)), (r"a \; b", _Mul(a, b)), (r"a \thickspace b", _Mul(a, b)), (r"a \quad b", _Mul(a, b)), (r"a \qquad b", _Mul(a, b)), (r"a \! b", _Mul(a, b)), (r"a \negthinspace b", _Mul(a, b)), (r"a \negmedspace b", _Mul(a, b)), (r"a \negthickspace b", _Mul(a, b)), (r"\int x \, dx", Integral(x, x)), (r"\log_2 x", _log(x, 2)), (r"\log_a x", _log(x, a)), (r"5^0 - 4^0", _Add(_Pow(5, 0), _Mul(-1, _Pow(4, 0)))), ] def test_parseable(): from sympy.parsing.latex import parse_latex for latex_str, sympy_expr in GOOD_PAIRS: assert parse_latex(latex_str) == sympy_expr, latex_str # These bad LaTeX strings should raise a LaTeXParsingError when parsed BAD_STRINGS = [ r"(", r")", r"\frac{d}{dx}", r"(\frac{d}{dx})", r"\sqrt{}", r"\sqrt", r"\overline{}", r"\overline", r"{", r"}", r"\mathit{x + y}", r"\mathit{21}", r"\frac{2}{}", r"\frac{}{2}", r"\int", r"!", r"!0", r"_", r"^", r"|", r"||x|", r"()", r"((((((((((((((((()))))))))))))))))", r"-", r"\frac{d}{dx} + \frac{d}{dt}", r"f(x,,y)", r"f(x,y,", r"\sin^x", r"\cos^2", r"@", r"#", r"$", r"%", r"&", r"*", r"" "\\", r"~", r"\frac{(2 + x}{1 - x)}", ] def test_not_parseable(): from sympy.parsing.latex import parse_latex, LaTeXParsingError for latex_str in BAD_STRINGS: with raises(LaTeXParsingError): parse_latex(latex_str) # At time of migration from latex2sympy, should fail but doesn't FAILING_BAD_STRINGS = [ r"\cos 1 \cos", r"f(,", r"f()", r"a \div \div b", r"a \cdot \cdot b", r"a // b", r"a +", r"1.1.1", r"1 +", r"a / b /", ] @XFAIL def test_failing_not_parseable(): from sympy.parsing.latex import parse_latex, LaTeXParsingError for latex_str in FAILING_BAD_STRINGS: with raises(LaTeXParsingError): parse_latex(latex_str)
06f8128b28b830334810a6e2363286dbfea6852906817cf7547c26ddc957e4a9
# Ported from latex2sympy by @augustt198 # https://github.com/augustt198/latex2sympy # See license in LICENSE.txt import sympy from sympy.external import import_module from sympy.printing.str import StrPrinter from sympy.physics.quantum.state import Bra, Ket from .errors import LaTeXParsingError LaTeXParser = LaTeXLexer = MathErrorListener = None try: LaTeXParser = import_module('sympy.parsing.latex._antlr.latexparser', import_kwargs={'fromlist': ['LaTeXParser']}).LaTeXParser LaTeXLexer = import_module('sympy.parsing.latex._antlr.latexlexer', import_kwargs={'fromlist': ['LaTeXLexer']}).LaTeXLexer except Exception: pass ErrorListener = import_module('antlr4.error.ErrorListener', warn_not_installed=True, import_kwargs={'fromlist': ['ErrorListener']} ) if ErrorListener: class MathErrorListener(ErrorListener.ErrorListener): # type: ignore def __init__(self, src): super(ErrorListener.ErrorListener, self).__init__() self.src = src def syntaxError(self, recog, symbol, line, col, msg, e): fmt = "%s\n%s\n%s" marker = "~" * col + "^" if msg.startswith("missing"): err = fmt % (msg, self.src, marker) elif msg.startswith("no viable"): err = fmt % ("I expected something else here", self.src, marker) elif msg.startswith("mismatched"): names = LaTeXParser.literalNames expected = [ names[i] for i in e.getExpectedTokens() if i < len(names) ] if len(expected) < 10: expected = " ".join(expected) err = (fmt % ("I expected one of these: " + expected, self.src, marker)) else: err = (fmt % ("I expected something else here", self.src, marker)) else: err = fmt % ("I don't understand this", self.src, marker) raise LaTeXParsingError(err) def parse_latex(sympy): antlr4 = import_module('antlr4', warn_not_installed=True) if None in [antlr4, MathErrorListener]: raise ImportError("LaTeX parsing requires the antlr4 python package," " provided by pip (antlr4-python2-runtime or" " antlr4-python3-runtime) or" " conda (antlr-python-runtime)") matherror = MathErrorListener(sympy) stream = antlr4.InputStream(sympy) lex = LaTeXLexer(stream) lex.removeErrorListeners() lex.addErrorListener(matherror) tokens = antlr4.CommonTokenStream(lex) parser = LaTeXParser(tokens) # remove default console error listener parser.removeErrorListeners() parser.addErrorListener(matherror) relation = parser.math().relation() expr = convert_relation(relation) return expr def convert_relation(rel): if rel.expr(): return convert_expr(rel.expr()) lh = convert_relation(rel.relation(0)) rh = convert_relation(rel.relation(1)) if rel.LT(): return sympy.StrictLessThan(lh, rh) elif rel.LTE(): return sympy.LessThan(lh, rh) elif rel.GT(): return sympy.StrictGreaterThan(lh, rh) elif rel.GTE(): return sympy.GreaterThan(lh, rh) elif rel.EQUAL(): return sympy.Eq(lh, rh) elif rel.NEQ(): return sympy.Ne(lh, rh) def convert_expr(expr): return convert_add(expr.additive()) def convert_add(add): if add.ADD(): lh = convert_add(add.additive(0)) rh = convert_add(add.additive(1)) return sympy.Add(lh, rh, evaluate=False) elif add.SUB(): lh = convert_add(add.additive(0)) rh = convert_add(add.additive(1)) return sympy.Add(lh, sympy.Mul(-1, rh, evaluate=False), evaluate=False) else: return convert_mp(add.mp()) def convert_mp(mp): if hasattr(mp, 'mp'): mp_left = mp.mp(0) mp_right = mp.mp(1) else: mp_left = mp.mp_nofunc(0) mp_right = mp.mp_nofunc(1) if mp.MUL() or mp.CMD_TIMES() or mp.CMD_CDOT(): lh = convert_mp(mp_left) rh = convert_mp(mp_right) return sympy.Mul(lh, rh, evaluate=False) elif mp.DIV() or mp.CMD_DIV() or mp.COLON(): lh = convert_mp(mp_left) rh = convert_mp(mp_right) return sympy.Mul(lh, sympy.Pow(rh, -1, evaluate=False), evaluate=False) else: if hasattr(mp, 'unary'): return convert_unary(mp.unary()) else: return convert_unary(mp.unary_nofunc()) def convert_unary(unary): if hasattr(unary, 'unary'): nested_unary = unary.unary() else: nested_unary = unary.unary_nofunc() if hasattr(unary, 'postfix_nofunc'): first = unary.postfix() tail = unary.postfix_nofunc() postfix = [first] + tail else: postfix = unary.postfix() if unary.ADD(): return convert_unary(nested_unary) elif unary.SUB(): numabs = convert_unary(nested_unary) # Use Integer(-n) instead of Mul(-1, n) return -numabs elif postfix: return convert_postfix_list(postfix) def convert_postfix_list(arr, i=0): if i >= len(arr): raise LaTeXParsingError("Index out of bounds") res = convert_postfix(arr[i]) if isinstance(res, sympy.Expr): if i == len(arr) - 1: return res # nothing to multiply by else: if i > 0: left = convert_postfix(arr[i - 1]) right = convert_postfix(arr[i + 1]) if isinstance(left, sympy.Expr) and isinstance( right, sympy.Expr): left_syms = convert_postfix(arr[i - 1]).atoms(sympy.Symbol) right_syms = convert_postfix(arr[i + 1]).atoms( sympy.Symbol) # if the left and right sides contain no variables and the # symbol in between is 'x', treat as multiplication. if len(left_syms) == 0 and len(right_syms) == 0 and str( res) == "x": return convert_postfix_list(arr, i + 1) # multiply by next return sympy.Mul( res, convert_postfix_list(arr, i + 1), evaluate=False) else: # must be derivative wrt = res[0] if i == len(arr) - 1: raise LaTeXParsingError("Expected expression for derivative") else: expr = convert_postfix_list(arr, i + 1) return sympy.Derivative(expr, wrt) def do_subs(expr, at): if at.expr(): at_expr = convert_expr(at.expr()) syms = at_expr.atoms(sympy.Symbol) if len(syms) == 0: return expr elif len(syms) > 0: sym = next(iter(syms)) return expr.subs(sym, at_expr) elif at.equality(): lh = convert_expr(at.equality().expr(0)) rh = convert_expr(at.equality().expr(1)) return expr.subs(lh, rh) def convert_postfix(postfix): if hasattr(postfix, 'exp'): exp_nested = postfix.exp() else: exp_nested = postfix.exp_nofunc() exp = convert_exp(exp_nested) for op in postfix.postfix_op(): if op.BANG(): if isinstance(exp, list): raise LaTeXParsingError("Cannot apply postfix to derivative") exp = sympy.factorial(exp, evaluate=False) elif op.eval_at(): ev = op.eval_at() at_b = None at_a = None if ev.eval_at_sup(): at_b = do_subs(exp, ev.eval_at_sup()) if ev.eval_at_sub(): at_a = do_subs(exp, ev.eval_at_sub()) if at_b is not None and at_a is not None: exp = sympy.Add(at_b, -1 * at_a, evaluate=False) elif at_b is not None: exp = at_b elif at_a is not None: exp = at_a return exp def convert_exp(exp): if hasattr(exp, 'exp'): exp_nested = exp.exp() else: exp_nested = exp.exp_nofunc() if exp_nested: base = convert_exp(exp_nested) if isinstance(base, list): raise LaTeXParsingError("Cannot raise derivative to power") if exp.atom(): exponent = convert_atom(exp.atom()) elif exp.expr(): exponent = convert_expr(exp.expr()) return sympy.Pow(base, exponent, evaluate=False) else: if hasattr(exp, 'comp'): return convert_comp(exp.comp()) else: return convert_comp(exp.comp_nofunc()) def convert_comp(comp): if comp.group(): return convert_expr(comp.group().expr()) elif comp.abs_group(): return sympy.Abs(convert_expr(comp.abs_group().expr()), evaluate=False) elif comp.atom(): return convert_atom(comp.atom()) elif comp.frac(): return convert_frac(comp.frac()) elif comp.binom(): return convert_binom(comp.binom()) elif comp.floor(): return convert_floor(comp.floor()) elif comp.ceil(): return convert_ceil(comp.ceil()) elif comp.func(): return convert_func(comp.func()) def convert_atom(atom): if atom.LETTER(): subscriptName = '' if atom.subexpr(): subscript = None if atom.subexpr().expr(): # subscript is expr subscript = convert_expr(atom.subexpr().expr()) else: # subscript is atom subscript = convert_atom(atom.subexpr().atom()) subscriptName = '_{' + StrPrinter().doprint(subscript) + '}' return sympy.Symbol(atom.LETTER().getText() + subscriptName) elif atom.SYMBOL(): s = atom.SYMBOL().getText()[1:] if s == "infty": return sympy.oo else: if atom.subexpr(): subscript = None if atom.subexpr().expr(): # subscript is expr subscript = convert_expr(atom.subexpr().expr()) else: # subscript is atom subscript = convert_atom(atom.subexpr().atom()) subscriptName = StrPrinter().doprint(subscript) s += '_{' + subscriptName + '}' return sympy.Symbol(s) elif atom.NUMBER(): s = atom.NUMBER().getText().replace(",", "") return sympy.Number(s) elif atom.DIFFERENTIAL(): var = get_differential_var(atom.DIFFERENTIAL()) return sympy.Symbol('d' + var.name) elif atom.mathit(): text = rule2text(atom.mathit().mathit_text()) return sympy.Symbol(text) elif atom.bra(): val = convert_expr(atom.bra().expr()) return Bra(val) elif atom.ket(): val = convert_expr(atom.ket().expr()) return Ket(val) def rule2text(ctx): stream = ctx.start.getInputStream() # starting index of starting token startIdx = ctx.start.start # stopping index of stopping token stopIdx = ctx.stop.stop return stream.getText(startIdx, stopIdx) def convert_frac(frac): diff_op = False partial_op = False lower_itv = frac.lower.getSourceInterval() lower_itv_len = lower_itv[1] - lower_itv[0] + 1 if (frac.lower.start == frac.lower.stop and frac.lower.start.type == LaTeXLexer.DIFFERENTIAL): wrt = get_differential_var_str(frac.lower.start.text) diff_op = True elif (lower_itv_len == 2 and frac.lower.start.type == LaTeXLexer.SYMBOL and frac.lower.start.text == '\\partial' and (frac.lower.stop.type == LaTeXLexer.LETTER or frac.lower.stop.type == LaTeXLexer.SYMBOL)): partial_op = True wrt = frac.lower.stop.text if frac.lower.stop.type == LaTeXLexer.SYMBOL: wrt = wrt[1:] if diff_op or partial_op: wrt = sympy.Symbol(wrt) if (diff_op and frac.upper.start == frac.upper.stop and frac.upper.start.type == LaTeXLexer.LETTER and frac.upper.start.text == 'd'): return [wrt] elif (partial_op and frac.upper.start == frac.upper.stop and frac.upper.start.type == LaTeXLexer.SYMBOL and frac.upper.start.text == '\\partial'): return [wrt] upper_text = rule2text(frac.upper) expr_top = None if diff_op and upper_text.startswith('d'): expr_top = parse_latex(upper_text[1:]) elif partial_op and frac.upper.start.text == '\\partial': expr_top = parse_latex(upper_text[len('\\partial'):]) if expr_top: return sympy.Derivative(expr_top, wrt) expr_top = convert_expr(frac.upper) expr_bot = convert_expr(frac.lower) inverse_denom = sympy.Pow(expr_bot, -1, evaluate=False) if expr_top == 1: return inverse_denom else: return sympy.Mul(expr_top, inverse_denom, evaluate=False) def convert_binom(binom): expr_n = convert_expr(binom.n) expr_k = convert_expr(binom.k) return sympy.binomial(expr_n, expr_k, evaluate=False) def convert_floor(floor): val = convert_expr(floor.val) return sympy.floor(val, evaluate=False) def convert_ceil(ceil): val = convert_expr(ceil.val) return sympy.ceiling(val, evaluate=False) def convert_func(func): if func.func_normal(): if func.L_PAREN(): # function called with parenthesis arg = convert_func_arg(func.func_arg()) else: arg = convert_func_arg(func.func_arg_noparens()) name = func.func_normal().start.text[1:] # change arc<trig> -> a<trig> if name in [ "arcsin", "arccos", "arctan", "arccsc", "arcsec", "arccot" ]: name = "a" + name[3:] expr = getattr(sympy.functions, name)(arg, evaluate=False) if name in ["arsinh", "arcosh", "artanh"]: name = "a" + name[2:] expr = getattr(sympy.functions, name)(arg, evaluate=False) if name == "exp": expr = sympy.exp(arg, evaluate=False) if (name == "log" or name == "ln"): if func.subexpr(): if func.subexpr().expr(): base = convert_expr(func.subexpr().expr()) else: base = convert_atom(func.subexpr().atom()) elif name == "log": base = 10 elif name == "ln": base = sympy.E expr = sympy.log(arg, base, evaluate=False) func_pow = None should_pow = True if func.supexpr(): if func.supexpr().expr(): func_pow = convert_expr(func.supexpr().expr()) else: func_pow = convert_atom(func.supexpr().atom()) if name in [ "sin", "cos", "tan", "csc", "sec", "cot", "sinh", "cosh", "tanh" ]: if func_pow == -1: name = "a" + name should_pow = False expr = getattr(sympy.functions, name)(arg, evaluate=False) if func_pow and should_pow: expr = sympy.Pow(expr, func_pow, evaluate=False) return expr elif func.LETTER() or func.SYMBOL(): if func.LETTER(): fname = func.LETTER().getText() elif func.SYMBOL(): fname = func.SYMBOL().getText()[1:] fname = str(fname) # can't be unicode if func.subexpr(): subscript = None if func.subexpr().expr(): # subscript is expr subscript = convert_expr(func.subexpr().expr()) else: # subscript is atom subscript = convert_atom(func.subexpr().atom()) subscriptName = StrPrinter().doprint(subscript) fname += '_{' + subscriptName + '}' input_args = func.args() output_args = [] while input_args.args(): # handle multiple arguments to function output_args.append(convert_expr(input_args.expr())) input_args = input_args.args() output_args.append(convert_expr(input_args.expr())) return sympy.Function(fname)(*output_args) elif func.FUNC_INT(): return handle_integral(func) elif func.FUNC_SQRT(): expr = convert_expr(func.base) if func.root: r = convert_expr(func.root) return sympy.root(expr, r, evaluate=False) else: return sympy.sqrt(expr, evaluate=False) elif func.FUNC_OVERLINE(): expr = convert_expr(func.base) return sympy.conjugate(expr, evaluate=False) elif func.FUNC_SUM(): return handle_sum_or_prod(func, "summation") elif func.FUNC_PROD(): return handle_sum_or_prod(func, "product") elif func.FUNC_LIM(): return handle_limit(func) def convert_func_arg(arg): if hasattr(arg, 'expr'): return convert_expr(arg.expr()) else: return convert_mp(arg.mp_nofunc()) def handle_integral(func): if func.additive(): integrand = convert_add(func.additive()) elif func.frac(): integrand = convert_frac(func.frac()) else: integrand = 1 int_var = None if func.DIFFERENTIAL(): int_var = get_differential_var(func.DIFFERENTIAL()) else: for sym in integrand.atoms(sympy.Symbol): s = str(sym) if len(s) > 1 and s[0] == 'd': if s[1] == '\\': int_var = sympy.Symbol(s[2:]) else: int_var = sympy.Symbol(s[1:]) int_sym = sym if int_var: integrand = integrand.subs(int_sym, 1) else: # Assume dx by default int_var = sympy.Symbol('x') if func.subexpr(): if func.subexpr().atom(): lower = convert_atom(func.subexpr().atom()) else: lower = convert_expr(func.subexpr().expr()) if func.supexpr().atom(): upper = convert_atom(func.supexpr().atom()) else: upper = convert_expr(func.supexpr().expr()) return sympy.Integral(integrand, (int_var, lower, upper)) else: return sympy.Integral(integrand, int_var) def handle_sum_or_prod(func, name): val = convert_mp(func.mp()) iter_var = convert_expr(func.subeq().equality().expr(0)) start = convert_expr(func.subeq().equality().expr(1)) if func.supexpr().expr(): # ^{expr} end = convert_expr(func.supexpr().expr()) else: # ^atom end = convert_atom(func.supexpr().atom()) if name == "summation": return sympy.Sum(val, (iter_var, start, end)) elif name == "product": return sympy.Product(val, (iter_var, start, end)) def handle_limit(func): sub = func.limit_sub() if sub.LETTER(): var = sympy.Symbol(sub.LETTER().getText()) elif sub.SYMBOL(): var = sympy.Symbol(sub.SYMBOL().getText()[1:]) else: var = sympy.Symbol('x') if sub.SUB(): direction = "-" else: direction = "+" approaching = convert_expr(sub.expr()) content = convert_mp(func.mp()) return sympy.Limit(content, var, approaching, direction) def get_differential_var(d): text = get_differential_var_str(d.getText()) return sympy.Symbol(text) def get_differential_var_str(text): for i in range(1, len(text)): c = text[i] if not (c == " " or c == "\r" or c == "\n" or c == "\t"): idx = i break text = text[idx:] if text[0] == "\\": text = text[1:] return text
8b3fd96cc6648d222675867cb70d089ccbb9d1083dcb269f7df079da25413bf7
""" Several methods to simplify expressions involving unit objects. """ from functools import reduce from collections.abc import Iterable from sympy import Add, Mul, Pow, Tuple, sympify from sympy.core.compatibility import ordered from sympy.matrices.common import NonInvertibleMatrixError from sympy.physics.units.dimensions import Dimension from sympy.physics.units.prefixes import Prefix from sympy.physics.units.quantities import Quantity from sympy.utilities.iterables import sift def _get_conversion_matrix_for_expr(expr, target_units, unit_system): from sympy import Matrix dimension_system = unit_system.get_dimension_system() expr_dim = Dimension(unit_system.get_dimensional_expr(expr)) dim_dependencies = dimension_system.get_dimensional_dependencies(expr_dim, mark_dimensionless=True) target_dims = [Dimension(unit_system.get_dimensional_expr(x)) for x in target_units] canon_dim_units = [i for x in target_dims for i in dimension_system.get_dimensional_dependencies(x, mark_dimensionless=True)] canon_expr_units = {i for i in dim_dependencies} if not canon_expr_units.issubset(set(canon_dim_units)): return None seen = set() canon_dim_units = [i for i in canon_dim_units if not (i in seen or seen.add(i))] camat = Matrix([[dimension_system.get_dimensional_dependencies(i, mark_dimensionless=True).get(j, 0) for i in target_dims] for j in canon_dim_units]) exprmat = Matrix([dim_dependencies.get(k, 0) for k in canon_dim_units]) try: res_exponents = camat.solve(exprmat) except NonInvertibleMatrixError: return None return res_exponents def convert_to(expr, target_units, unit_system="SI"): """ Convert ``expr`` to the same expression with all of its units and quantities represented as factors of ``target_units``, whenever the dimension is compatible. ``target_units`` may be a single unit/quantity, or a collection of units/quantities. Examples ======== >>> from sympy.physics.units import speed_of_light, meter, gram, second, day >>> from sympy.physics.units import mile, newton, kilogram, atomic_mass_constant >>> from sympy.physics.units import kilometer, centimeter >>> from sympy.physics.units import gravitational_constant, hbar >>> from sympy.physics.units import convert_to >>> convert_to(mile, kilometer) 25146*kilometer/15625 >>> convert_to(mile, kilometer).n() 1.609344*kilometer >>> convert_to(speed_of_light, meter/second) 299792458*meter/second >>> convert_to(day, second) 86400*second >>> 3*newton 3*newton >>> convert_to(3*newton, kilogram*meter/second**2) 3*kilogram*meter/second**2 >>> convert_to(atomic_mass_constant, gram) 1.660539060e-24*gram Conversion to multiple units: >>> convert_to(speed_of_light, [meter, second]) 299792458*meter/second >>> convert_to(3*newton, [centimeter, gram, second]) 300000*centimeter*gram/second**2 Conversion to Planck units: >>> convert_to(atomic_mass_constant, [gravitational_constant, speed_of_light, hbar]).n() 7.62963087839509e-20*hbar**0.5*speed_of_light**0.5/gravitational_constant**0.5 """ from sympy.physics.units import UnitSystem unit_system = UnitSystem.get_unit_system(unit_system) if not isinstance(target_units, (Iterable, Tuple)): target_units = [target_units] if isinstance(expr, Add): return Add.fromiter(convert_to(i, target_units, unit_system) for i in expr.args) expr = sympify(expr) if not isinstance(expr, Quantity) and expr.has(Quantity): expr = expr.replace(lambda x: isinstance(x, Quantity), lambda x: x.convert_to(target_units, unit_system)) def get_total_scale_factor(expr): if isinstance(expr, Mul): return reduce(lambda x, y: x * y, [get_total_scale_factor(i) for i in expr.args]) elif isinstance(expr, Pow): return get_total_scale_factor(expr.base) ** expr.exp elif isinstance(expr, Quantity): return unit_system.get_quantity_scale_factor(expr) return expr depmat = _get_conversion_matrix_for_expr(expr, target_units, unit_system) if depmat is None: return expr expr_scale_factor = get_total_scale_factor(expr) return expr_scale_factor * Mul.fromiter((1/get_total_scale_factor(u) * u) ** p for u, p in zip(target_units, depmat)) def quantity_simplify(expr): """Return an equivalent expression in which prefixes are replaced with numerical values and all units of a given dimension are the unified in a canonical manner. Examples ======== >>> from sympy.physics.units.util import quantity_simplify >>> from sympy.physics.units.prefixes import kilo >>> from sympy.physics.units import foot, inch >>> quantity_simplify(kilo*foot*inch) 250*foot**2/3 >>> quantity_simplify(foot - 6*inch) foot/2 """ if expr.is_Atom or not expr.has(Prefix, Quantity): return expr # replace all prefixes with numerical values p = expr.atoms(Prefix) expr = expr.xreplace({p: p.scale_factor for p in p}) # replace all quantities of given dimension with a canonical # quantity, chosen from those in the expression d = sift(expr.atoms(Quantity), lambda i: i.dimension) for k in d: if len(d[k]) == 1: continue v = list(ordered(d[k])) ref = v[0]/v[0].scale_factor expr = expr.xreplace({vi: ref*vi.scale_factor for vi in v[1:]}) return expr def check_dimensions(expr, unit_system="SI"): """Return expr if units in addends have the same base dimensions, else raise a ValueError.""" # the case of adding a number to a dimensional quantity # is ignored for the sake of SymPy core routines, so this # function will raise an error now if such an addend is # found. # Also, when doing substitutions, multiplicative constants # might be introduced, so remove those now from sympy.physics.units import UnitSystem unit_system = UnitSystem.get_unit_system(unit_system) def addDict(dict1, dict2): """Merge dictionaries by adding values of common keys and removing keys with value of 0.""" dict3 = {**dict1, **dict2} for key, value in dict3.items(): if key in dict1 and key in dict2: dict3[key] = value + dict1[key] return {key:val for key, val in dict3.items() if val != 0} adds = expr.atoms(Add) DIM_OF = unit_system.get_dimension_system().get_dimensional_dependencies for a in adds: deset = set() for ai in a.args: if ai.is_number: deset.add(()) continue dims = [] skip = False dimdict = {} for i in Mul.make_args(ai): if i.has(Quantity): i = Dimension(unit_system.get_dimensional_expr(i)) if i.has(Dimension): dimdict = addDict(dimdict, DIM_OF(i)) elif i.free_symbols: skip = True break dims.extend(dimdict.items()) if not skip: deset.add(tuple(sorted(dims))) if len(deset) > 1: raise ValueError( "addends have incompatible dimensions: {}".format(deset)) # clear multiplicative constants on Dimensions which may be # left after substitution reps = {} for m in expr.atoms(Mul): if any(isinstance(i, Dimension) for i in m.args): reps[m] = m.func(*[ i for i in m.args if not i.is_number]) return expr.xreplace(reps)
2582a75468e8501fdf3ac4a25ac7740b2addd64165546958669b70149df40a32
from sympy.core.backend import (diff, expand, sin, cos, sympify, eye, symbols, ImmutableMatrix as Matrix, MatrixBase) from sympy import (trigsimp, solve, Symbol, Dummy) from sympy.physics.vector.vector import Vector, _check_vector from sympy.utilities.misc import translate from warnings import warn __all__ = ['CoordinateSym', 'ReferenceFrame'] class CoordinateSym(Symbol): """ A coordinate symbol/base scalar associated wrt a Reference Frame. Ideally, users should not instantiate this class. Instances of this class must only be accessed through the corresponding frame as 'frame[index]'. CoordinateSyms having the same frame and index parameters are equal (even though they may be instantiated separately). Parameters ========== name : string The display name of the CoordinateSym frame : ReferenceFrame The reference frame this base scalar belongs to index : 0, 1 or 2 The index of the dimension denoted by this coordinate variable Examples ======== >>> from sympy.physics.vector import ReferenceFrame, CoordinateSym >>> A = ReferenceFrame('A') >>> A[1] A_y >>> type(A[0]) <class 'sympy.physics.vector.frame.CoordinateSym'> >>> a_y = CoordinateSym('a_y', A, 1) >>> a_y == A[1] True """ def __new__(cls, name, frame, index): # We can't use the cached Symbol.__new__ because this class depends on # frame and index, which are not passed to Symbol.__xnew__. assumptions = {} super()._sanitize(assumptions, cls) obj = super().__xnew__(cls, name, **assumptions) _check_frame(frame) if index not in range(0, 3): raise ValueError("Invalid index specified") obj._id = (frame, index) return obj @property def frame(self): return self._id[0] def __eq__(self, other): #Check if the other object is a CoordinateSym of the same frame #and same index if isinstance(other, CoordinateSym): if other._id == self._id: return True return False def __ne__(self, other): return not self == other def __hash__(self): return tuple((self._id[0].__hash__(), self._id[1])).__hash__() class ReferenceFrame: """A reference frame in classical mechanics. ReferenceFrame is a class used to represent a reference frame in classical mechanics. It has a standard basis of three unit vectors in the frame's x, y, and z directions. It also can have a rotation relative to a parent frame; this rotation is defined by a direction cosine matrix relating this frame's basis vectors to the parent frame's basis vectors. It can also have an angular velocity vector, defined in another frame. """ _count = 0 def __init__(self, name, indices=None, latexs=None, variables=None): """ReferenceFrame initialization method. A ReferenceFrame has a set of orthonormal basis vectors, along with orientations relative to other ReferenceFrames and angular velocities relative to other ReferenceFrames. Parameters ========== indices : tuple of str Enables the reference frame's basis unit vectors to be accessed by Python's square bracket indexing notation using the provided three indice strings and alters the printing of the unit vectors to reflect this choice. latexs : tuple of str Alters the LaTeX printing of the reference frame's basis unit vectors to the provided three valid LaTeX strings. Examples ======== >>> from sympy.physics.vector import ReferenceFrame, vlatex >>> N = ReferenceFrame('N') >>> N.x N.x >>> O = ReferenceFrame('O', indices=('1', '2', '3')) >>> O.x O['1'] >>> O['1'] O['1'] >>> P = ReferenceFrame('P', latexs=('A1', 'A2', 'A3')) >>> vlatex(P.x) 'A1' symbols() can be used to create multiple Reference Frames in one step, for example: >>> from sympy.physics.vector import ReferenceFrame >>> from sympy import symbols >>> A, B, C = symbols('A B C', cls=ReferenceFrame) >>> D, E = symbols('D E', cls=ReferenceFrame, indices=('1', '2', '3')) >>> A[0] A_x >>> D.x D['1'] >>> E.y E['2'] >>> type(A) == type(D) True """ if not isinstance(name, str): raise TypeError('Need to supply a valid name') # The if statements below are for custom printing of basis-vectors for # each frame. # First case, when custom indices are supplied if indices is not None: if not isinstance(indices, (tuple, list)): raise TypeError('Supply the indices as a list') if len(indices) != 3: raise ValueError('Supply 3 indices') for i in indices: if not isinstance(i, str): raise TypeError('Indices must be strings') self.str_vecs = [(name + '[\'' + indices[0] + '\']'), (name + '[\'' + indices[1] + '\']'), (name + '[\'' + indices[2] + '\']')] self.pretty_vecs = [(name.lower() + "_" + indices[0]), (name.lower() + "_" + indices[1]), (name.lower() + "_" + indices[2])] self.latex_vecs = [(r"\mathbf{\hat{%s}_{%s}}" % (name.lower(), indices[0])), (r"\mathbf{\hat{%s}_{%s}}" % (name.lower(), indices[1])), (r"\mathbf{\hat{%s}_{%s}}" % (name.lower(), indices[2]))] self.indices = indices # Second case, when no custom indices are supplied else: self.str_vecs = [(name + '.x'), (name + '.y'), (name + '.z')] self.pretty_vecs = [name.lower() + "_x", name.lower() + "_y", name.lower() + "_z"] self.latex_vecs = [(r"\mathbf{\hat{%s}_x}" % name.lower()), (r"\mathbf{\hat{%s}_y}" % name.lower()), (r"\mathbf{\hat{%s}_z}" % name.lower())] self.indices = ['x', 'y', 'z'] # Different step, for custom latex basis vectors if latexs is not None: if not isinstance(latexs, (tuple, list)): raise TypeError('Supply the indices as a list') if len(latexs) != 3: raise ValueError('Supply 3 indices') for i in latexs: if not isinstance(i, str): raise TypeError('Latex entries must be strings') self.latex_vecs = latexs self.name = name self._var_dict = {} #The _dcm_dict dictionary will only store the dcms of adjacent parent-child #relationships. The _dcm_cache dictionary will store calculated dcm along with #all content of _dcm_dict for faster retrieval of dcms. self._dcm_dict = {} self._dcm_cache = {} self._ang_vel_dict = {} self._ang_acc_dict = {} self._dlist = [self._dcm_dict, self._ang_vel_dict, self._ang_acc_dict] self._cur = 0 self._x = Vector([(Matrix([1, 0, 0]), self)]) self._y = Vector([(Matrix([0, 1, 0]), self)]) self._z = Vector([(Matrix([0, 0, 1]), self)]) #Associate coordinate symbols wrt this frame if variables is not None: if not isinstance(variables, (tuple, list)): raise TypeError('Supply the variable names as a list/tuple') if len(variables) != 3: raise ValueError('Supply 3 variable names') for i in variables: if not isinstance(i, str): raise TypeError('Variable names must be strings') else: variables = [name + '_x', name + '_y', name + '_z'] self.varlist = (CoordinateSym(variables[0], self, 0), \ CoordinateSym(variables[1], self, 1), \ CoordinateSym(variables[2], self, 2)) ReferenceFrame._count += 1 self.index = ReferenceFrame._count def __getitem__(self, ind): """ Returns basis vector for the provided index, if the index is a string. If the index is a number, returns the coordinate variable correspon- -ding to that index. """ if not isinstance(ind, str): if ind < 3: return self.varlist[ind] else: raise ValueError("Invalid index provided") if self.indices[0] == ind: return self.x if self.indices[1] == ind: return self.y if self.indices[2] == ind: return self.z else: raise ValueError('Not a defined index') def __iter__(self): return iter([self.x, self.y, self.z]) def __str__(self): """Returns the name of the frame. """ return self.name __repr__ = __str__ def _dict_list(self, other, num): """Returns an inclusive list of reference frames that connect this reference frame to the provided reference frame. Parameters ========== other : ReferenceFrame The other reference frame to look for a connecting relationship to. num : integer ``0``, ``1``, and ``2`` will look for orientation, angular velocity, and angular acceleration relationships between the two frames, respectively. Returns ======= list Inclusive list of reference frames that connect this reference frame to the other reference frame. Examples ======== >>> from sympy.physics.vector import ReferenceFrame >>> A = ReferenceFrame('A') >>> B = ReferenceFrame('B') >>> C = ReferenceFrame('C') >>> D = ReferenceFrame('D') >>> B.orient_axis(A, A.x, 1.0) >>> C.orient_axis(B, B.x, 1.0) >>> D.orient_axis(C, C.x, 1.0) >>> D._dict_list(A, 0) [D, C, B, A] Raises ====== ValueError When no path is found between the two reference frames or ``num`` is an incorrect value. """ connect_type = {0: 'orientation', 1: 'angular velocity', 2: 'angular acceleration'} if num not in connect_type.keys(): raise ValueError('Valid values for num are 0, 1, or 2.') possible_connecting_paths = [[self]] oldlist = [[]] while possible_connecting_paths != oldlist: oldlist = possible_connecting_paths[:] # make a copy for frame_list in possible_connecting_paths: frames_adjacent_to_last = frame_list[-1]._dlist[num].keys() for adjacent_frame in frames_adjacent_to_last: if adjacent_frame not in frame_list: connecting_path = frame_list + [adjacent_frame] if connecting_path not in possible_connecting_paths: possible_connecting_paths.append(connecting_path) for connecting_path in oldlist: if connecting_path[-1] != other: possible_connecting_paths.remove(connecting_path) possible_connecting_paths.sort(key=len) if len(possible_connecting_paths) != 0: return possible_connecting_paths[0] # selects the shortest path msg = 'No connecting {} path found between {} and {}.' raise ValueError(msg.format(connect_type[num], self.name, other.name)) def _w_diff_dcm(self, otherframe): """Angular velocity from time differentiating the DCM. """ from sympy.physics.vector.functions import dynamicsymbols dcm2diff = otherframe.dcm(self) diffed = dcm2diff.diff(dynamicsymbols._t) angvelmat = diffed * dcm2diff.T w1 = trigsimp(expand(angvelmat[7]), recursive=True) w2 = trigsimp(expand(angvelmat[2]), recursive=True) w3 = trigsimp(expand(angvelmat[3]), recursive=True) return Vector([(Matrix([w1, w2, w3]), otherframe)]) def variable_map(self, otherframe): """ Returns a dictionary which expresses the coordinate variables of this frame in terms of the variables of otherframe. If Vector.simp is True, returns a simplified version of the mapped values. Else, returns them without simplification. Simplification of the expressions may take time. Parameters ========== otherframe : ReferenceFrame The other frame to map the variables to Examples ======== >>> from sympy.physics.vector import ReferenceFrame, dynamicsymbols >>> A = ReferenceFrame('A') >>> q = dynamicsymbols('q') >>> B = A.orientnew('B', 'Axis', [q, A.z]) >>> A.variable_map(B) {A_x: B_x*cos(q(t)) - B_y*sin(q(t)), A_y: B_x*sin(q(t)) + B_y*cos(q(t)), A_z: B_z} """ _check_frame(otherframe) if (otherframe, Vector.simp) in self._var_dict: return self._var_dict[(otherframe, Vector.simp)] else: vars_matrix = self.dcm(otherframe) * Matrix(otherframe.varlist) mapping = {} for i, x in enumerate(self): if Vector.simp: mapping[self.varlist[i]] = trigsimp(vars_matrix[i], method='fu') else: mapping[self.varlist[i]] = vars_matrix[i] self._var_dict[(otherframe, Vector.simp)] = mapping return mapping def ang_acc_in(self, otherframe): """Returns the angular acceleration Vector of the ReferenceFrame. Effectively returns the Vector: ^N alpha ^B which represent the angular acceleration of B in N, where B is self, and N is otherframe. Parameters ========== otherframe : ReferenceFrame The ReferenceFrame which the angular acceleration is returned in. Examples ======== >>> from sympy.physics.vector import ReferenceFrame >>> N = ReferenceFrame('N') >>> A = ReferenceFrame('A') >>> V = 10 * N.x >>> A.set_ang_acc(N, V) >>> A.ang_acc_in(N) 10*N.x """ _check_frame(otherframe) if otherframe in self._ang_acc_dict: return self._ang_acc_dict[otherframe] else: return self.ang_vel_in(otherframe).dt(otherframe) def ang_vel_in(self, otherframe): """Returns the angular velocity Vector of the ReferenceFrame. Effectively returns the Vector: ^N omega ^B which represent the angular velocity of B in N, where B is self, and N is otherframe. Parameters ========== otherframe : ReferenceFrame The ReferenceFrame which the angular velocity is returned in. Examples ======== >>> from sympy.physics.vector import ReferenceFrame >>> N = ReferenceFrame('N') >>> A = ReferenceFrame('A') >>> V = 10 * N.x >>> A.set_ang_vel(N, V) >>> A.ang_vel_in(N) 10*N.x """ _check_frame(otherframe) flist = self._dict_list(otherframe, 1) outvec = Vector(0) for i in range(len(flist) - 1): outvec += flist[i]._ang_vel_dict[flist[i + 1]] return outvec def dcm(self, otherframe): r"""Returns the direction cosine matrix relative to the provided reference frame. The returned matrix can be used to express the orthogonal unit vectors of this frame in terms of the orthogonal unit vectors of ``otherframe``. Parameters ========== otherframe : ReferenceFrame The reference frame which the direction cosine matrix of this frame is formed relative to. Examples ======== The following example rotates the reference frame A relative to N by a simple rotation and then calculates the direction cosine matrix of N relative to A. >>> from sympy import symbols, sin, cos >>> from sympy.physics.vector import ReferenceFrame >>> q1 = symbols('q1') >>> N = ReferenceFrame('N') >>> A = N.orientnew('A', 'Axis', (q1, N.x)) >>> N.dcm(A) Matrix([ [1, 0, 0], [0, cos(q1), -sin(q1)], [0, sin(q1), cos(q1)]]) The second row of the above direction cosine matrix represents the ``N.y`` unit vector in N expressed in A. Like so: >>> Ny = 0*A.x + cos(q1)*A.y - sin(q1)*A.z Thus, expressing ``N.y`` in A should return the same result: >>> N.y.express(A) cos(q1)*A.y - sin(q1)*A.z Notes ===== It is import to know what form of the direction cosine matrix is returned. If ``B.dcm(A)`` is called, it means the "direction cosine matrix of B relative to A". This is the matrix :math:`^{\mathbf{A}} \mathbf{R} ^{\mathbf{B}}` shown in the following relationship: .. math:: \begin{bmatrix} \hat{\mathbf{b}}_1 \\ \hat{\mathbf{b}}_2 \\ \hat{\mathbf{b}}_3 \end{bmatrix} = {}^A\mathbf{R}^B \begin{bmatrix} \hat{\mathbf{a}}_1 \\ \hat{\mathbf{a}}_2 \\ \hat{\mathbf{a}}_3 \end{bmatrix}. :math:`{}^A\mathbf{R}^B` is the matrix that expresses the B unit vectors in terms of the A unit vectors. """ _check_frame(otherframe) # Check if the dcm wrt that frame has already been calculated if otherframe in self._dcm_cache: return self._dcm_cache[otherframe] flist = self._dict_list(otherframe, 0) outdcm = eye(3) for i in range(len(flist) - 1): outdcm = outdcm * flist[i]._dcm_dict[flist[i + 1]] # After calculation, store the dcm in dcm cache for faster future # retrieval self._dcm_cache[otherframe] = outdcm otherframe._dcm_cache[self] = outdcm.T return outdcm def _dcm(self, parent, parent_orient): # If parent.oreint(self) is already defined,then # update the _dcm_dict of parent while over write # all content of self._dcm_dict and self._dcm_cache # with new dcm relation. # Else update _dcm_cache and _dcm_dict of both # self and parent. frames = self._dcm_cache.keys() dcm_dict_del = [] dcm_cache_del = [] if parent in frames: for frame in frames: if frame in self._dcm_dict: dcm_dict_del += [frame] dcm_cache_del += [frame] # Reset the _dcm_cache of this frame, and remove it from the # _dcm_caches of the frames it is linked to. Also remove it from the # _dcm_dict of its parent for frame in dcm_dict_del: del frame._dcm_dict[self] for frame in dcm_cache_del: del frame._dcm_cache[self] # Reset the _dcm_dict self._dcm_dict = self._dlist[0] = {} # Reset the _dcm_cache self._dcm_cache = {} else: #Check for loops and raise warning accordingly. visited = [] queue = list(frames) cont = True #Flag to control queue loop. while queue and cont: node = queue.pop(0) if node not in visited: visited.append(node) neighbors = node._dcm_dict.keys() for neighbor in neighbors: if neighbor == parent: warn('Loops are defined among the orientation of frames.' + \ ' This is likely not desired and may cause errors in your calculations.') cont = False break queue.append(neighbor) # Add the dcm relationship to _dcm_dict self._dcm_dict.update({parent: parent_orient.T}) parent._dcm_dict.update({self: parent_orient}) # Update the dcm cache self._dcm_cache.update({parent: parent_orient.T}) parent._dcm_cache.update({self: parent_orient}) def orient_axis(self, parent, axis, angle): """Sets the orientation of this reference frame with respect to a parent reference frame by rotating through an angle about an axis fixed in the parent reference frame. Parameters ========== parent : ReferenceFrame Reference frame that this reference frame will be rotated relative to. axis : Vector Vector fixed in the parent frame about about which this frame is rotated. It need not be a unit vector and the rotation follows the right hand rule. angle : sympifiable Angle in radians by which it the frame is to be rotated. Warns ====== UserWarning If the orientation creates a kinematic loop. Examples ======== Setup variables for the examples: >>> from sympy import symbols >>> from sympy.physics.vector import ReferenceFrame >>> q1 = symbols('q1') >>> N = ReferenceFrame('N') >>> B = ReferenceFrame('B') >>> B.orient_axis(N, N.x, q1) The ``orient_axis()`` method generates a direction cosine matrix and its transpose which defines the orientation of B relative to N and vice versa. Once orient is called, ``dcm()`` outputs the appropriate direction cosine matrix: >>> B.dcm(N) Matrix([ [1, 0, 0], [0, cos(q1), sin(q1)], [0, -sin(q1), cos(q1)]]) >>> N.dcm(B) Matrix([ [1, 0, 0], [0, cos(q1), -sin(q1)], [0, sin(q1), cos(q1)]]) The following two lines show that the sense of the rotation can be defined by negating the vector direction or the angle. Both lines produce the same result. >>> B.orient_axis(N, -N.x, q1) >>> B.orient_axis(N, N.x, -q1) """ from sympy.physics.vector.functions import dynamicsymbols _check_frame(parent) amount = sympify(angle) theta = amount axis = _check_vector(axis) parent_orient_axis = [] if not axis.dt(parent) == 0: raise ValueError('Axis cannot be time-varying.') unit_axis = axis.express(parent).normalize() unit_col = unit_axis.args[0][0] parent_orient_axis = ( (eye(3) - unit_col * unit_col.T) * cos(theta) + Matrix([[0, -unit_col[2], unit_col[1]], [unit_col[2], 0, -unit_col[0]], [-unit_col[1], unit_col[0], 0]]) * sin(theta) + unit_col * unit_col.T) self._dcm(parent, parent_orient_axis) thetad = (amount).diff(dynamicsymbols._t) wvec = thetad*axis.express(parent).normalize() self._ang_vel_dict.update({parent: wvec}) parent._ang_vel_dict.update({self: -wvec}) self._var_dict = {} def orient_explicit(self, parent, dcm): """Sets the orientation of this reference frame relative to a parent reference frame by explicitly setting the direction cosine matrix. Parameters ========== parent : ReferenceFrame Reference frame that this reference frame will be rotated relative to. dcm : Matrix, shape(3, 3) Direction cosine matrix that specifies the relative rotation between the two reference frames. Warns ====== UserWarning If the orientation creates a kinematic loop. Examples ======== Setup variables for the examples: >>> from sympy import symbols, Matrix, sin, cos >>> from sympy.physics.vector import ReferenceFrame >>> q1 = symbols('q1') >>> A = ReferenceFrame('A') >>> B = ReferenceFrame('B') >>> N = ReferenceFrame('N') A simple rotation of ``A`` relative to ``N`` about ``N.x`` is defined by the following direction cosine matrix: >>> dcm = Matrix([[1, 0, 0], ... [0, cos(q1), -sin(q1)], ... [0, sin(q1), cos(q1)]]) >>> A.orient_explicit(N, dcm) >>> A.dcm(N) Matrix([ [1, 0, 0], [0, cos(q1), sin(q1)], [0, -sin(q1), cos(q1)]]) This is equivalent to using ``orient_axis()``: >>> B.orient_axis(N, N.x, q1) >>> B.dcm(N) Matrix([ [1, 0, 0], [0, cos(q1), sin(q1)], [0, -sin(q1), cos(q1)]]) **Note carefully that** ``N.dcm(B)`` **(the transpose) would be passed into** ``orient_explicit()`` **for** ``A.dcm(N)`` **to match** ``B.dcm(N)``: >>> A.orient_explicit(N, N.dcm(B)) >>> A.dcm(N) Matrix([ [1, 0, 0], [0, cos(q1), sin(q1)], [0, -sin(q1), cos(q1)]]) """ _check_frame(parent) # amounts must be a Matrix type object # (e.g. sympy.matrices.dense.MutableDenseMatrix). if not isinstance(dcm, MatrixBase): raise TypeError("Amounts must be a sympy Matrix type object.") parent_orient_dcm = [] parent_orient_dcm = dcm self._dcm(parent, parent_orient_dcm) wvec = self._w_diff_dcm(parent) self._ang_vel_dict.update({parent: wvec}) parent._ang_vel_dict.update({self: -wvec}) self._var_dict = {} def _rot(self, axis, angle): """DCM for simple axis 1,2,or 3 rotations.""" if axis == 1: return Matrix([[1, 0, 0], [0, cos(angle), -sin(angle)], [0, sin(angle), cos(angle)]]) elif axis == 2: return Matrix([[cos(angle), 0, sin(angle)], [0, 1, 0], [-sin(angle), 0, cos(angle)]]) elif axis == 3: return Matrix([[cos(angle), -sin(angle), 0], [sin(angle), cos(angle), 0], [0, 0, 1]]) def orient_body_fixed(self, parent, angles, rotation_order): """Rotates this reference frame relative to the parent reference frame by right hand rotating through three successive body fixed simple axis rotations. Each subsequent axis of rotation is about the "body fixed" unit vectors of a new intermediate reference frame. This type of rotation is also referred to rotating through the `Euler and Tait-Bryan Angles`_. .. _Euler and Tait-Bryan Angles: https://en.wikipedia.org/wiki/Euler_angles Parameters ========== parent : ReferenceFrame Reference frame that this reference frame will be rotated relative to. angles : 3-tuple of sympifiable Three angles in radians used for the successive rotations. rotation_order : 3 character string or 3 digit integer Order of the rotations about each intermediate reference frames' unit vectors. The Euler rotation about the X, Z', X'' axes can be specified by the strings ``'XZX'``, ``'131'``, or the integer ``131``. There are 12 unique valid rotation orders (6 Euler and 6 Tait-Bryan): zxz, xyx, yzy, zyz, xzx, yxy, xyz, yzx, zxy, xzy, zyx, and yxz. Warns ====== UserWarning If the orientation creates a kinematic loop. Examples ======== Setup variables for the examples: >>> from sympy import symbols >>> from sympy.physics.vector import ReferenceFrame >>> q1, q2, q3 = symbols('q1, q2, q3') >>> N = ReferenceFrame('N') >>> B = ReferenceFrame('B') >>> B1 = ReferenceFrame('B1') >>> B2 = ReferenceFrame('B2') >>> B3 = ReferenceFrame('B3') For example, a classic Euler Angle rotation can be done by: >>> B.orient_body_fixed(N, (q1, q2, q3), 'XYX') >>> B.dcm(N) Matrix([ [ cos(q2), sin(q1)*sin(q2), -sin(q2)*cos(q1)], [sin(q2)*sin(q3), -sin(q1)*sin(q3)*cos(q2) + cos(q1)*cos(q3), sin(q1)*cos(q3) + sin(q3)*cos(q1)*cos(q2)], [sin(q2)*cos(q3), -sin(q1)*cos(q2)*cos(q3) - sin(q3)*cos(q1), -sin(q1)*sin(q3) + cos(q1)*cos(q2)*cos(q3)]]) This rotates reference frame B relative to reference frame N through ``q1`` about ``N.x``, then rotates B again through ``q2`` about ``B.y``, and finally through ``q3`` about ``B.x``. It is equivalent to three successive ``orient_axis()`` calls: >>> B1.orient_axis(N, N.x, q1) >>> B2.orient_axis(B1, B1.y, q2) >>> B3.orient_axis(B2, B2.x, q3) >>> B3.dcm(N) Matrix([ [ cos(q2), sin(q1)*sin(q2), -sin(q2)*cos(q1)], [sin(q2)*sin(q3), -sin(q1)*sin(q3)*cos(q2) + cos(q1)*cos(q3), sin(q1)*cos(q3) + sin(q3)*cos(q1)*cos(q2)], [sin(q2)*cos(q3), -sin(q1)*cos(q2)*cos(q3) - sin(q3)*cos(q1), -sin(q1)*sin(q3) + cos(q1)*cos(q2)*cos(q3)]]) Acceptable rotation orders are of length 3, expressed in as a string ``'XYZ'`` or ``'123'`` or integer ``123``. Rotations about an axis twice in a row are prohibited. >>> B.orient_body_fixed(N, (q1, q2, 0), 'ZXZ') >>> B.orient_body_fixed(N, (q1, q2, 0), '121') >>> B.orient_body_fixed(N, (q1, q2, q3), 123) """ _check_frame(parent) amounts = list(angles) for i, v in enumerate(amounts): if not isinstance(v, Vector): amounts[i] = sympify(v) approved_orders = ('123', '231', '312', '132', '213', '321', '121', '131', '212', '232', '313', '323', '') # make sure XYZ => 123 rot_order = translate(str(rotation_order), 'XYZxyz', '123123') if rot_order not in approved_orders: raise TypeError('The rotation order is not a valid order.') parent_orient_body = [] if not (len(amounts) == 3 & len(rot_order) == 3): raise TypeError('Body orientation takes 3 values & 3 orders') a1 = int(rot_order[0]) a2 = int(rot_order[1]) a3 = int(rot_order[2]) parent_orient_body = (self._rot(a1, amounts[0]) * self._rot(a2, amounts[1]) * self._rot(a3, amounts[2])) self._dcm(parent, parent_orient_body) try: from sympy.polys.polyerrors import CoercionFailed from sympy.physics.vector.functions import kinematic_equations q1, q2, q3 = amounts u1, u2, u3 = symbols('u1, u2, u3', cls=Dummy) templist = kinematic_equations([u1, u2, u3], [q1, q2, q3], 'body', rot_order) templist = [expand(i) for i in templist] td = solve(templist, [u1, u2, u3]) u1 = expand(td[u1]) u2 = expand(td[u2]) u3 = expand(td[u3]) wvec = u1 * self.x + u2 * self.y + u3 * self.z except (CoercionFailed, AssertionError): wvec = self._w_diff_dcm(parent) self._ang_vel_dict.update({parent: wvec}) parent._ang_vel_dict.update({self: -wvec}) self._var_dict = {} def orient_space_fixed(self, parent, angles, rotation_order): """Rotates this reference frame relative to the parent reference frame by right hand rotating through three successive space fixed simple axis rotations. Each subsequent axis of rotation is about the "space fixed" unit vectors of the parent reference frame. Parameters ========== parent : ReferenceFrame Reference frame that this reference frame will be rotated relative to. angles : 3-tuple of sympifiable Three angles in radians used for the successive rotations. rotation_order : 3 character string or 3 digit integer Order of the rotations about the parent reference frame's unit vectors. The order can be specified by the strings ``'XZX'``, ``'131'``, or the integer ``131``. There are 12 unique valid rotation orders. Warns ====== UserWarning If the orientation creates a kinematic loop. Examples ======== Setup variables for the examples: >>> from sympy import symbols >>> from sympy.physics.vector import ReferenceFrame >>> q1, q2, q3 = symbols('q1, q2, q3') >>> N = ReferenceFrame('N') >>> B = ReferenceFrame('B') >>> B1 = ReferenceFrame('B1') >>> B2 = ReferenceFrame('B2') >>> B3 = ReferenceFrame('B3') >>> B.orient_space_fixed(N, (q1, q2, q3), '312') >>> B.dcm(N) Matrix([ [ sin(q1)*sin(q2)*sin(q3) + cos(q1)*cos(q3), sin(q1)*cos(q2), sin(q1)*sin(q2)*cos(q3) - sin(q3)*cos(q1)], [-sin(q1)*cos(q3) + sin(q2)*sin(q3)*cos(q1), cos(q1)*cos(q2), sin(q1)*sin(q3) + sin(q2)*cos(q1)*cos(q3)], [ sin(q3)*cos(q2), -sin(q2), cos(q2)*cos(q3)]]) is equivalent to: >>> B1.orient_axis(N, N.z, q1) >>> B2.orient_axis(B1, N.x, q2) >>> B3.orient_axis(B2, N.y, q3) >>> B3.dcm(N).simplify() Matrix([ [ sin(q1)*sin(q2)*sin(q3) + cos(q1)*cos(q3), sin(q1)*cos(q2), sin(q1)*sin(q2)*cos(q3) - sin(q3)*cos(q1)], [-sin(q1)*cos(q3) + sin(q2)*sin(q3)*cos(q1), cos(q1)*cos(q2), sin(q1)*sin(q3) + sin(q2)*cos(q1)*cos(q3)], [ sin(q3)*cos(q2), -sin(q2), cos(q2)*cos(q3)]]) It is worth noting that space-fixed and body-fixed rotations are related by the order of the rotations, i.e. the reverse order of body fixed will give space fixed and vice versa. >>> B.orient_space_fixed(N, (q1, q2, q3), '231') >>> B.dcm(N) Matrix([ [cos(q1)*cos(q2), sin(q1)*sin(q3) + sin(q2)*cos(q1)*cos(q3), -sin(q1)*cos(q3) + sin(q2)*sin(q3)*cos(q1)], [ -sin(q2), cos(q2)*cos(q3), sin(q3)*cos(q2)], [sin(q1)*cos(q2), sin(q1)*sin(q2)*cos(q3) - sin(q3)*cos(q1), sin(q1)*sin(q2)*sin(q3) + cos(q1)*cos(q3)]]) >>> B.orient_body_fixed(N, (q3, q2, q1), '132') >>> B.dcm(N) Matrix([ [cos(q1)*cos(q2), sin(q1)*sin(q3) + sin(q2)*cos(q1)*cos(q3), -sin(q1)*cos(q3) + sin(q2)*sin(q3)*cos(q1)], [ -sin(q2), cos(q2)*cos(q3), sin(q3)*cos(q2)], [sin(q1)*cos(q2), sin(q1)*sin(q2)*cos(q3) - sin(q3)*cos(q1), sin(q1)*sin(q2)*sin(q3) + cos(q1)*cos(q3)]]) """ _check_frame(parent) amounts = list(angles) for i, v in enumerate(amounts): if not isinstance(v, Vector): amounts[i] = sympify(v) approved_orders = ('123', '231', '312', '132', '213', '321', '121', '131', '212', '232', '313', '323', '') # make sure XYZ => 123 rot_order = translate(str(rotation_order), 'XYZxyz', '123123') if rot_order not in approved_orders: raise TypeError('The supplied order is not an approved type') parent_orient_space = [] if not (len(amounts) == 3 & len(rot_order) == 3): raise TypeError('Space orientation takes 3 values & 3 orders') a1 = int(rot_order[0]) a2 = int(rot_order[1]) a3 = int(rot_order[2]) parent_orient_space = (self._rot(a3, amounts[2]) * self._rot(a2, amounts[1]) * self._rot(a1, amounts[0])) self._dcm(parent, parent_orient_space) try: from sympy.polys.polyerrors import CoercionFailed from sympy.physics.vector.functions import kinematic_equations q1, q2, q3 = amounts u1, u2, u3 = symbols('u1, u2, u3', cls=Dummy) templist = kinematic_equations([u1, u2, u3], [q1, q2, q3], 'space', rot_order) templist = [expand(i) for i in templist] td = solve(templist, [u1, u2, u3]) u1 = expand(td[u1]) u2 = expand(td[u2]) u3 = expand(td[u3]) wvec = u1 * self.x + u2 * self.y + u3 * self.z except (CoercionFailed, AssertionError): wvec = self._w_diff_dcm(parent) self._ang_vel_dict.update({parent: wvec}) parent._ang_vel_dict.update({self: -wvec}) self._var_dict = {} def orient_quaternion(self, parent, numbers): """Sets the orientation of this reference frame relative to a parent reference frame via an orientation quaternion. An orientation quaternion is defined as a finite rotation a unit vector, ``(lambda_x, lambda_y, lambda_z)``, by an angle ``theta``. The orientation quaternion is described by four parameters: - ``q0 = cos(theta/2)`` - ``q1 = lambda_x*sin(theta/2)`` - ``q2 = lambda_y*sin(theta/2)`` - ``q3 = lambda_z*sin(theta/2)`` See `Quaternions and Spatial Rotation <https://en.wikipedia.org/wiki/Quaternions_and_spatial_rotation>`_ on Wikipedia for more information. Parameters ========== parent : ReferenceFrame Reference frame that this reference frame will be rotated relative to. numbers : 4-tuple of sympifiable The four quaternion scalar numbers as defined above: ``q0``, ``q1``, ``q2``, ``q3``. Warns ====== UserWarning If the orientation creates a kinematic loop. Examples ======== Setup variables for the examples: >>> from sympy import symbols >>> from sympy.physics.vector import ReferenceFrame >>> q0, q1, q2, q3 = symbols('q0 q1 q2 q3') >>> N = ReferenceFrame('N') >>> B = ReferenceFrame('B') Set the orientation: >>> B.orient_quaternion(N, (q0, q1, q2, q3)) >>> B.dcm(N) Matrix([ [q0**2 + q1**2 - q2**2 - q3**2, 2*q0*q3 + 2*q1*q2, -2*q0*q2 + 2*q1*q3], [ -2*q0*q3 + 2*q1*q2, q0**2 - q1**2 + q2**2 - q3**2, 2*q0*q1 + 2*q2*q3], [ 2*q0*q2 + 2*q1*q3, -2*q0*q1 + 2*q2*q3, q0**2 - q1**2 - q2**2 + q3**2]]) """ from sympy.physics.vector.functions import dynamicsymbols _check_frame(parent) numbers = list(numbers) for i, v in enumerate(numbers): if not isinstance(v, Vector): numbers[i] = sympify(v) parent_orient_quaternion = [] if not (isinstance(numbers, (list, tuple)) & (len(numbers) == 4)): raise TypeError('Amounts are a list or tuple of length 4') q0, q1, q2, q3 = numbers parent_orient_quaternion = ( Matrix([[q0**2 + q1**2 - q2**2 - q3**2, 2 * (q1 * q2 - q0 * q3), 2 * (q0 * q2 + q1 * q3)], [2 * (q1 * q2 + q0 * q3), q0**2 - q1**2 + q2**2 - q3**2, 2 * (q2 * q3 - q0 * q1)], [2 * (q1 * q3 - q0 * q2), 2 * (q0 * q1 + q2 * q3), q0**2 - q1**2 - q2**2 + q3**2]])) self._dcm(parent, parent_orient_quaternion) t = dynamicsymbols._t q0, q1, q2, q3 = numbers q0d = diff(q0, t) q1d = diff(q1, t) q2d = diff(q2, t) q3d = diff(q3, t) w1 = 2 * (q1d * q0 + q2d * q3 - q3d * q2 - q0d * q1) w2 = 2 * (q2d * q0 + q3d * q1 - q1d * q3 - q0d * q2) w3 = 2 * (q3d * q0 + q1d * q2 - q2d * q1 - q0d * q3) wvec = Vector([(Matrix([w1, w2, w3]), self)]) self._ang_vel_dict.update({parent: wvec}) parent._ang_vel_dict.update({self: -wvec}) self._var_dict = {} def orient(self, parent, rot_type, amounts, rot_order=''): """Sets the orientation of this reference frame relative to another (parent) reference frame. .. note:: It is now recommended to use the ``.orient_axis, .orient_body_fixed, .orient_space_fixed, .orient_quaternion`` methods for the different rotation types. Parameters ========== parent : ReferenceFrame Reference frame that this reference frame will be rotated relative to. rot_type : str The method used to generate the direction cosine matrix. Supported methods are: - ``'Axis'``: simple rotations about a single common axis - ``'DCM'``: for setting the direction cosine matrix directly - ``'Body'``: three successive rotations about new intermediate axes, also called "Euler and Tait-Bryan angles" - ``'Space'``: three successive rotations about the parent frames' unit vectors - ``'Quaternion'``: rotations defined by four parameters which result in a singularity free direction cosine matrix amounts : Expressions defining the rotation angles or direction cosine matrix. These must match the ``rot_type``. See examples below for details. The input types are: - ``'Axis'``: 2-tuple (expr/sym/func, Vector) - ``'DCM'``: Matrix, shape(3,3) - ``'Body'``: 3-tuple of expressions, symbols, or functions - ``'Space'``: 3-tuple of expressions, symbols, or functions - ``'Quaternion'``: 4-tuple of expressions, symbols, or functions rot_order : str or int, optional If applicable, the order of the successive of rotations. The string ``'123'`` and integer ``123`` are equivalent, for example. Required for ``'Body'`` and ``'Space'``. Warns ====== UserWarning If the orientation creates a kinematic loop. """ _check_frame(parent) approved_orders = ('123', '231', '312', '132', '213', '321', '121', '131', '212', '232', '313', '323', '') rot_order = translate(str(rot_order), 'XYZxyz', '123123') rot_type = rot_type.upper() if rot_order not in approved_orders: raise TypeError('The supplied order is not an approved type') if rot_type == 'AXIS': self.orient_axis(parent, amounts[1], amounts[0]) elif rot_type == 'DCM': self.orient_explicit(parent, amounts) elif rot_type == 'BODY': self.orient_body_fixed(parent, amounts, rot_order) elif rot_type == 'SPACE': self.orient_space_fixed(parent, amounts, rot_order) elif rot_type == 'QUATERNION': self.orient_quaternion(parent, amounts) else: raise NotImplementedError('That is not an implemented rotation') def orientnew(self, newname, rot_type, amounts, rot_order='', variables=None, indices=None, latexs=None): r"""Returns a new reference frame oriented with respect to this reference frame. See ``ReferenceFrame.orient()`` for detailed examples of how to orient reference frames. Parameters ========== newname : str Name for the new reference frame. rot_type : str The method used to generate the direction cosine matrix. Supported methods are: - ``'Axis'``: simple rotations about a single common axis - ``'DCM'``: for setting the direction cosine matrix directly - ``'Body'``: three successive rotations about new intermediate axes, also called "Euler and Tait-Bryan angles" - ``'Space'``: three successive rotations about the parent frames' unit vectors - ``'Quaternion'``: rotations defined by four parameters which result in a singularity free direction cosine matrix amounts : Expressions defining the rotation angles or direction cosine matrix. These must match the ``rot_type``. See examples below for details. The input types are: - ``'Axis'``: 2-tuple (expr/sym/func, Vector) - ``'DCM'``: Matrix, shape(3,3) - ``'Body'``: 3-tuple of expressions, symbols, or functions - ``'Space'``: 3-tuple of expressions, symbols, or functions - ``'Quaternion'``: 4-tuple of expressions, symbols, or functions rot_order : str or int, optional If applicable, the order of the successive of rotations. The string ``'123'`` and integer ``123`` are equivalent, for example. Required for ``'Body'`` and ``'Space'``. indices : tuple of str Enables the reference frame's basis unit vectors to be accessed by Python's square bracket indexing notation using the provided three indice strings and alters the printing of the unit vectors to reflect this choice. latexs : tuple of str Alters the LaTeX printing of the reference frame's basis unit vectors to the provided three valid LaTeX strings. Examples ======== >>> from sympy import symbols >>> from sympy.physics.vector import ReferenceFrame, vlatex >>> q0, q1, q2, q3 = symbols('q0 q1 q2 q3') >>> N = ReferenceFrame('N') Create a new reference frame A rotated relative to N through a simple rotation. >>> A = N.orientnew('A', 'Axis', (q0, N.x)) Create a new reference frame B rotated relative to N through body-fixed rotations. >>> B = N.orientnew('B', 'Body', (q1, q2, q3), '123') Create a new reference frame C rotated relative to N through a simple rotation with unique indices and LaTeX printing. >>> C = N.orientnew('C', 'Axis', (q0, N.x), indices=('1', '2', '3'), ... latexs=(r'\hat{\mathbf{c}}_1',r'\hat{\mathbf{c}}_2', ... r'\hat{\mathbf{c}}_3')) >>> C['1'] C['1'] >>> print(vlatex(C['1'])) \hat{\mathbf{c}}_1 """ newframe = self.__class__(newname, variables=variables, indices=indices, latexs=latexs) approved_orders = ('123', '231', '312', '132', '213', '321', '121', '131', '212', '232', '313', '323', '') rot_order = translate(str(rot_order), 'XYZxyz', '123123') rot_type = rot_type.upper() if rot_order not in approved_orders: raise TypeError('The supplied order is not an approved type') if rot_type == 'AXIS': newframe.orient_axis(self, amounts[1], amounts[0]) elif rot_type == 'DCM': newframe.orient_explicit(self, amounts) elif rot_type == 'BODY': newframe.orient_body_fixed(self, amounts, rot_order) elif rot_type == 'SPACE': newframe.orient_space_fixed(self, amounts, rot_order) elif rot_type == 'QUATERNION': newframe.orient_quaternion(self, amounts) else: raise NotImplementedError('That is not an implemented rotation') return newframe def set_ang_acc(self, otherframe, value): """Define the angular acceleration Vector in a ReferenceFrame. Defines the angular acceleration of this ReferenceFrame, in another. Angular acceleration can be defined with respect to multiple different ReferenceFrames. Care must be taken to not create loops which are inconsistent. Parameters ========== otherframe : ReferenceFrame A ReferenceFrame to define the angular acceleration in value : Vector The Vector representing angular acceleration Examples ======== >>> from sympy.physics.vector import ReferenceFrame >>> N = ReferenceFrame('N') >>> A = ReferenceFrame('A') >>> V = 10 * N.x >>> A.set_ang_acc(N, V) >>> A.ang_acc_in(N) 10*N.x """ if value == 0: value = Vector(0) value = _check_vector(value) _check_frame(otherframe) self._ang_acc_dict.update({otherframe: value}) otherframe._ang_acc_dict.update({self: -value}) def set_ang_vel(self, otherframe, value): """Define the angular velocity vector in a ReferenceFrame. Defines the angular velocity of this ReferenceFrame, in another. Angular velocity can be defined with respect to multiple different ReferenceFrames. Care must be taken to not create loops which are inconsistent. Parameters ========== otherframe : ReferenceFrame A ReferenceFrame to define the angular velocity in value : Vector The Vector representing angular velocity Examples ======== >>> from sympy.physics.vector import ReferenceFrame >>> N = ReferenceFrame('N') >>> A = ReferenceFrame('A') >>> V = 10 * N.x >>> A.set_ang_vel(N, V) >>> A.ang_vel_in(N) 10*N.x """ if value == 0: value = Vector(0) value = _check_vector(value) _check_frame(otherframe) self._ang_vel_dict.update({otherframe: value}) otherframe._ang_vel_dict.update({self: -value}) @property def x(self): """The basis Vector for the ReferenceFrame, in the x direction. """ return self._x @property def y(self): """The basis Vector for the ReferenceFrame, in the y direction. """ return self._y @property def z(self): """The basis Vector for the ReferenceFrame, in the z direction. """ return self._z def partial_velocity(self, frame, *gen_speeds): """Returns the partial angular velocities of this frame in the given frame with respect to one or more provided generalized speeds. Parameters ========== frame : ReferenceFrame The frame with which the angular velocity is defined in. gen_speeds : functions of time The generalized speeds. Returns ======= partial_velocities : tuple of Vector The partial angular velocity vectors corresponding to the provided generalized speeds. Examples ======== >>> from sympy.physics.vector import ReferenceFrame, dynamicsymbols >>> N = ReferenceFrame('N') >>> A = ReferenceFrame('A') >>> u1, u2 = dynamicsymbols('u1, u2') >>> A.set_ang_vel(N, u1 * A.x + u2 * N.y) >>> A.partial_velocity(N, u1) A.x >>> A.partial_velocity(N, u1, u2) (A.x, N.y) """ partials = [self.ang_vel_in(frame).diff(speed, frame, var_in_dcm=False) for speed in gen_speeds] if len(partials) == 1: return partials[0] else: return tuple(partials) def _check_frame(other): from .vector import VectorTypeError if not isinstance(other, ReferenceFrame): raise VectorTypeError(other, ReferenceFrame('A'))
9a3f50a4d30dd0ae0647278d97a21756e763ad95c05380472675d281e5a07188
from sympy import Pow, Tuple, pi, sstr, sympify, symbols from sympy.physics.units import ( G, centimeter, coulomb, day, degree, gram, hbar, hour, inch, joule, kelvin, kilogram, kilometer, length, meter, mile, minute, newton, planck, planck_length, planck_mass, planck_temperature, planck_time, radians, second, speed_of_light, steradian, time, km) from sympy.physics.units.util import convert_to, check_dimensions from sympy.testing.pytest import raises def NS(e, n=15, **options): return sstr(sympify(e).evalf(n, **options), full_prec=True) L = length T = time def test_dim_simplify_add(): # assert Add(L, L) == L assert L + L == L def test_dim_simplify_mul(): # assert Mul(L, T) == L*T assert L*T == L*T def test_dim_simplify_pow(): assert Pow(L, 2) == L**2 def test_dim_simplify_rec(): # assert Mul(Add(L, L), T) == L*T assert (L + L) * T == L*T def test_convert_to_quantities(): assert convert_to(3, meter) == 3 assert convert_to(mile, kilometer) == 25146*kilometer/15625 assert convert_to(meter/second, speed_of_light) == speed_of_light/299792458 assert convert_to(299792458*meter/second, speed_of_light) == speed_of_light assert convert_to(2*299792458*meter/second, speed_of_light) == 2*speed_of_light assert convert_to(speed_of_light, meter/second) == 299792458*meter/second assert convert_to(2*speed_of_light, meter/second) == 599584916*meter/second assert convert_to(day, second) == 86400*second assert convert_to(2*hour, minute) == 120*minute assert convert_to(mile, meter) == 201168*meter/125 assert convert_to(mile/hour, kilometer/hour) == 25146*kilometer/(15625*hour) assert convert_to(3*newton, meter/second) == 3*newton assert convert_to(3*newton, kilogram*meter/second**2) == 3*meter*kilogram/second**2 assert convert_to(kilometer + mile, meter) == 326168*meter/125 assert convert_to(2*kilometer + 3*mile, meter) == 853504*meter/125 assert convert_to(inch**2, meter**2) == 16129*meter**2/25000000 assert convert_to(3*inch**2, meter) == 48387*meter**2/25000000 assert convert_to(2*kilometer/hour + 3*mile/hour, meter/second) == 53344*meter/(28125*second) assert convert_to(2*kilometer/hour + 3*mile/hour, centimeter/second) == 213376*centimeter/(1125*second) assert convert_to(kilometer * (mile + kilometer), meter) == 2609344 * meter ** 2 assert convert_to(steradian, coulomb) == steradian assert convert_to(radians, degree) == 180*degree/pi assert convert_to(radians, [meter, degree]) == 180*degree/pi assert convert_to(pi*radians, degree) == 180*degree assert convert_to(pi, degree) == 180*degree def test_convert_to_tuples_of_quantities(): assert convert_to(speed_of_light, [meter, second]) == 299792458 * meter / second assert convert_to(speed_of_light, (meter, second)) == 299792458 * meter / second assert convert_to(speed_of_light, Tuple(meter, second)) == 299792458 * meter / second assert convert_to(joule, [meter, kilogram, second]) == kilogram*meter**2/second**2 assert convert_to(joule, [centimeter, gram, second]) == 10000000*centimeter**2*gram/second**2 assert convert_to(299792458*meter/second, [speed_of_light]) == speed_of_light assert convert_to(speed_of_light / 2, [meter, second, kilogram]) == meter/second*299792458 / 2 # This doesn't make physically sense, but let's keep it as a conversion test: assert convert_to(2 * speed_of_light, [meter, second, kilogram]) == 2 * 299792458 * meter / second assert convert_to(G, [G, speed_of_light, planck]) == 1.0*G assert NS(convert_to(meter, [G, speed_of_light, hbar]), n=7) == '6.187142e+34*gravitational_constant**0.5000000*hbar**0.5000000/speed_of_light**1.500000' assert NS(convert_to(planck_mass, kilogram), n=7) == '2.176434e-8*kilogram' assert NS(convert_to(planck_length, meter), n=7) == '1.616255e-35*meter' assert NS(convert_to(planck_time, second), n=6) == '5.39125e-44*second' assert NS(convert_to(planck_temperature, kelvin), n=7) == '1.416784e+32*kelvin' assert NS(convert_to(convert_to(meter, [G, speed_of_light, planck]), meter), n=10) == '1.000000000*meter' def test_eval_simplify(): from sympy.physics.units import cm, mm, km, m, K, kilo from sympy.core.symbol import symbols x, y = symbols('x y') assert (cm/mm).simplify() == 10 assert (km/m).simplify() == 1000 assert (km/cm).simplify() == 100000 assert (10*x*K*km**2/m/cm).simplify() == 1000000000*x*kelvin assert (cm/km/m).simplify() == 1/(10000000*centimeter) assert (3*kilo*meter).simplify() == 3000*meter assert (4*kilo*meter/(2*kilometer)).simplify() == 2 assert (4*kilometer**2/(kilo*meter)**2).simplify() == 4 def test_quantity_simplify(): from sympy.physics.units.util import quantity_simplify from sympy.physics.units import kilo, foot from sympy.core.symbol import symbols x, y = symbols('x y') assert quantity_simplify(x*(8*kilo*newton*meter + y)) == x*(8000*meter*newton + y) assert quantity_simplify(foot*inch*(foot + inch)) == foot**2*(foot + foot/12)/12 assert quantity_simplify(foot*inch*(foot*foot + inch*(foot + inch))) == foot**2*(foot**2 + foot/12*(foot + foot/12))/12 assert quantity_simplify(2**(foot/inch*kilo/1000)*inch) == 4096*foot/12 assert quantity_simplify(foot**2*inch + inch**2*foot) == 13*foot**3/144 def test_check_dimensions(): x = symbols('x') assert check_dimensions(inch + x) == inch + x assert check_dimensions(length + x) == length + x # after subs we get 2*length; check will clear the constant assert check_dimensions((length + x).subs(x, length)) == length assert check_dimensions(newton*meter + joule) == joule + meter*newton raises(ValueError, lambda: check_dimensions(inch + 1)) raises(ValueError, lambda: check_dimensions(length + 1)) raises(ValueError, lambda: check_dimensions(length + time)) raises(ValueError, lambda: check_dimensions(meter + second)) raises(ValueError, lambda: check_dimensions(2 * meter + second)) raises(ValueError, lambda: check_dimensions(2 * meter + 3 * second)) raises(ValueError, lambda: check_dimensions(1 / second + 1 / meter)) raises(ValueError, lambda: check_dimensions(2 * meter*(mile + centimeter) + km))
4d4c89bcc99e5537364c593f7e28c796bff233bd1b36a5c00659c1672d544353
from sympy import (symbols, sin, cos, pi, zeros, eye, simplify, ImmutableMatrix as Matrix) from sympy.physics.vector import (ReferenceFrame, Vector, CoordinateSym, dynamicsymbols, time_derivative, express, dot) from sympy.physics.vector.frame import _check_frame from sympy.physics.vector.vector import VectorTypeError from sympy.testing.pytest import raises import warnings Vector.simp = True def test_dict_list(): A = ReferenceFrame('A') B = ReferenceFrame('B') C = ReferenceFrame('C') D = ReferenceFrame('D') E = ReferenceFrame('E') F = ReferenceFrame('F') B.orient_axis(A, A.x, 1.0) C.orient_axis(B, B.x, 1.0) D.orient_axis(C, C.x, 1.0) assert D._dict_list(A, 0) == [D, C, B, A] E.orient_axis(D, D.x, 1.0) assert C._dict_list(A, 0) == [C, B, A] assert C._dict_list(E, 0) == [C, D, E] # only 0, 1, 2 permitted for second argument raises(ValueError, lambda: C._dict_list(E, 5)) # no connecting path raises(ValueError, lambda: F._dict_list(A, 0)) def test_coordinate_vars(): """Tests the coordinate variables functionality""" A = ReferenceFrame('A') assert CoordinateSym('Ax', A, 0) == A[0] assert CoordinateSym('Ax', A, 1) == A[1] assert CoordinateSym('Ax', A, 2) == A[2] raises(ValueError, lambda: CoordinateSym('Ax', A, 3)) q = dynamicsymbols('q') qd = dynamicsymbols('q', 1) assert isinstance(A[0], CoordinateSym) and \ isinstance(A[0], CoordinateSym) and \ isinstance(A[0], CoordinateSym) assert A.variable_map(A) == {A[0]:A[0], A[1]:A[1], A[2]:A[2]} assert A[0].frame == A B = A.orientnew('B', 'Axis', [q, A.z]) assert B.variable_map(A) == {B[2]: A[2], B[1]: -A[0]*sin(q) + A[1]*cos(q), B[0]: A[0]*cos(q) + A[1]*sin(q)} assert A.variable_map(B) == {A[0]: B[0]*cos(q) - B[1]*sin(q), A[1]: B[0]*sin(q) + B[1]*cos(q), A[2]: B[2]} assert time_derivative(B[0], A) == -A[0]*sin(q)*qd + A[1]*cos(q)*qd assert time_derivative(B[1], A) == -A[0]*cos(q)*qd - A[1]*sin(q)*qd assert time_derivative(B[2], A) == 0 assert express(B[0], A, variables=True) == A[0]*cos(q) + A[1]*sin(q) assert express(B[1], A, variables=True) == -A[0]*sin(q) + A[1]*cos(q) assert express(B[2], A, variables=True) == A[2] assert time_derivative(A[0]*A.x + A[1]*A.y + A[2]*A.z, B) == A[1]*qd*A.x - A[0]*qd*A.y assert time_derivative(B[0]*B.x + B[1]*B.y + B[2]*B.z, A) == - B[1]*qd*B.x + B[0]*qd*B.y assert express(B[0]*B[1]*B[2], A, variables=True) == \ A[2]*(-A[0]*sin(q) + A[1]*cos(q))*(A[0]*cos(q) + A[1]*sin(q)) assert (time_derivative(B[0]*B[1]*B[2], A) - (A[2]*(-A[0]**2*cos(2*q) - 2*A[0]*A[1]*sin(2*q) + A[1]**2*cos(2*q))*qd)).trigsimp() == 0 assert express(B[0]*B.x + B[1]*B.y + B[2]*B.z, A) == \ (B[0]*cos(q) - B[1]*sin(q))*A.x + (B[0]*sin(q) + \ B[1]*cos(q))*A.y + B[2]*A.z assert express(B[0]*B.x + B[1]*B.y + B[2]*B.z, A, variables=True) == \ A[0]*A.x + A[1]*A.y + A[2]*A.z assert express(A[0]*A.x + A[1]*A.y + A[2]*A.z, B) == \ (A[0]*cos(q) + A[1]*sin(q))*B.x + \ (-A[0]*sin(q) + A[1]*cos(q))*B.y + A[2]*B.z assert express(A[0]*A.x + A[1]*A.y + A[2]*A.z, B, variables=True) == \ B[0]*B.x + B[1]*B.y + B[2]*B.z N = B.orientnew('N', 'Axis', [-q, B.z]) assert N.variable_map(A) == {N[0]: A[0], N[2]: A[2], N[1]: A[1]} C = A.orientnew('C', 'Axis', [q, A.x + A.y + A.z]) mapping = A.variable_map(C) assert mapping[A[0]] == 2*C[0]*cos(q)/3 + C[0]/3 - 2*C[1]*sin(q + pi/6)/3 +\ C[1]/3 - 2*C[2]*cos(q + pi/3)/3 + C[2]/3 assert mapping[A[1]] == -2*C[0]*cos(q + pi/3)/3 + \ C[0]/3 + 2*C[1]*cos(q)/3 + C[1]/3 - 2*C[2]*sin(q + pi/6)/3 + C[2]/3 assert mapping[A[2]] == -2*C[0]*sin(q + pi/6)/3 + C[0]/3 - \ 2*C[1]*cos(q + pi/3)/3 + C[1]/3 + 2*C[2]*cos(q)/3 + C[2]/3 def test_ang_vel(): q1, q2, q3, q4 = dynamicsymbols('q1 q2 q3 q4') q1d, q2d, q3d, q4d = dynamicsymbols('q1 q2 q3 q4', 1) N = ReferenceFrame('N') A = N.orientnew('A', 'Axis', [q1, N.z]) B = A.orientnew('B', 'Axis', [q2, A.x]) C = B.orientnew('C', 'Axis', [q3, B.y]) D = N.orientnew('D', 'Axis', [q4, N.y]) u1, u2, u3 = dynamicsymbols('u1 u2 u3') assert A.ang_vel_in(N) == (q1d)*A.z assert B.ang_vel_in(N) == (q2d)*B.x + (q1d)*A.z assert C.ang_vel_in(N) == (q3d)*C.y + (q2d)*B.x + (q1d)*A.z A2 = N.orientnew('A2', 'Axis', [q4, N.y]) assert N.ang_vel_in(N) == 0 assert N.ang_vel_in(A) == -q1d*N.z assert N.ang_vel_in(B) == -q1d*A.z - q2d*B.x assert N.ang_vel_in(C) == -q1d*A.z - q2d*B.x - q3d*B.y assert N.ang_vel_in(A2) == -q4d*N.y assert A.ang_vel_in(N) == q1d*N.z assert A.ang_vel_in(A) == 0 assert A.ang_vel_in(B) == - q2d*B.x assert A.ang_vel_in(C) == - q2d*B.x - q3d*B.y assert A.ang_vel_in(A2) == q1d*N.z - q4d*N.y assert B.ang_vel_in(N) == q1d*A.z + q2d*A.x assert B.ang_vel_in(A) == q2d*A.x assert B.ang_vel_in(B) == 0 assert B.ang_vel_in(C) == -q3d*B.y assert B.ang_vel_in(A2) == q1d*A.z + q2d*A.x - q4d*N.y assert C.ang_vel_in(N) == q1d*A.z + q2d*A.x + q3d*B.y assert C.ang_vel_in(A) == q2d*A.x + q3d*C.y assert C.ang_vel_in(B) == q3d*B.y assert C.ang_vel_in(C) == 0 assert C.ang_vel_in(A2) == q1d*A.z + q2d*A.x + q3d*B.y - q4d*N.y assert A2.ang_vel_in(N) == q4d*A2.y assert A2.ang_vel_in(A) == q4d*A2.y - q1d*N.z assert A2.ang_vel_in(B) == q4d*N.y - q1d*A.z - q2d*A.x assert A2.ang_vel_in(C) == q4d*N.y - q1d*A.z - q2d*A.x - q3d*B.y assert A2.ang_vel_in(A2) == 0 C.set_ang_vel(N, u1*C.x + u2*C.y + u3*C.z) assert C.ang_vel_in(N) == (u1)*C.x + (u2)*C.y + (u3)*C.z assert N.ang_vel_in(C) == (-u1)*C.x + (-u2)*C.y + (-u3)*C.z assert C.ang_vel_in(D) == (u1)*C.x + (u2)*C.y + (u3)*C.z + (-q4d)*D.y assert D.ang_vel_in(C) == (-u1)*C.x + (-u2)*C.y + (-u3)*C.z + (q4d)*D.y q0 = dynamicsymbols('q0') q0d = dynamicsymbols('q0', 1) E = N.orientnew('E', 'Quaternion', (q0, q1, q2, q3)) assert E.ang_vel_in(N) == ( 2 * (q1d * q0 + q2d * q3 - q3d * q2 - q0d * q1) * E.x + 2 * (q2d * q0 + q3d * q1 - q1d * q3 - q0d * q2) * E.y + 2 * (q3d * q0 + q1d * q2 - q2d * q1 - q0d * q3) * E.z) F = N.orientnew('F', 'Body', (q1, q2, q3), 313) assert F.ang_vel_in(N) == ((sin(q2)*sin(q3)*q1d + cos(q3)*q2d)*F.x + (sin(q2)*cos(q3)*q1d - sin(q3)*q2d)*F.y + (cos(q2)*q1d + q3d)*F.z) G = N.orientnew('G', 'Axis', (q1, N.x + N.y)) assert G.ang_vel_in(N) == q1d * (N.x + N.y).normalize() assert N.ang_vel_in(G) == -q1d * (N.x + N.y).normalize() def test_dcm(): q1, q2, q3, q4 = dynamicsymbols('q1 q2 q3 q4') N = ReferenceFrame('N') A = N.orientnew('A', 'Axis', [q1, N.z]) B = A.orientnew('B', 'Axis', [q2, A.x]) C = B.orientnew('C', 'Axis', [q3, B.y]) D = N.orientnew('D', 'Axis', [q4, N.y]) E = N.orientnew('E', 'Space', [q1, q2, q3], '123') assert N.dcm(C) == Matrix([ [- sin(q1) * sin(q2) * sin(q3) + cos(q1) * cos(q3), - sin(q1) * cos(q2), sin(q1) * sin(q2) * cos(q3) + sin(q3) * cos(q1)], [sin(q1) * cos(q3) + sin(q2) * sin(q3) * cos(q1), cos(q1) * cos(q2), sin(q1) * sin(q3) - sin(q2) * cos(q1) * cos(q3)], [- sin(q3) * cos(q2), sin(q2), cos(q2) * cos(q3)]]) # This is a little touchy. Is it ok to use simplify in assert? test_mat = D.dcm(C) - Matrix( [[cos(q1) * cos(q3) * cos(q4) - sin(q3) * (- sin(q4) * cos(q2) + sin(q1) * sin(q2) * cos(q4)), - sin(q2) * sin(q4) - sin(q1) * cos(q2) * cos(q4), sin(q3) * cos(q1) * cos(q4) + cos(q3) * (- sin(q4) * cos(q2) + sin(q1) * sin(q2) * cos(q4))], [sin(q1) * cos(q3) + sin(q2) * sin(q3) * cos(q1), cos(q1) * cos(q2), sin(q1) * sin(q3) - sin(q2) * cos(q1) * cos(q3)], [sin(q4) * cos(q1) * cos(q3) - sin(q3) * (cos(q2) * cos(q4) + sin(q1) * sin(q2) * sin(q4)), sin(q2) * cos(q4) - sin(q1) * sin(q4) * cos(q2), sin(q3) * sin(q4) * cos(q1) + cos(q3) * (cos(q2) * cos(q4) + sin(q1) * sin(q2) * sin(q4))]]) assert test_mat.expand() == zeros(3, 3) assert E.dcm(N) == Matrix( [[cos(q2)*cos(q3), sin(q3)*cos(q2), -sin(q2)], [sin(q1)*sin(q2)*cos(q3) - sin(q3)*cos(q1), sin(q1)*sin(q2)*sin(q3) + cos(q1)*cos(q3), sin(q1)*cos(q2)], [sin(q1)*sin(q3) + sin(q2)*cos(q1)*cos(q3), - sin(q1)*cos(q3) + sin(q2)*sin(q3)*cos(q1), cos(q1)*cos(q2)]]) def test_w_diff_dcm1(): # Ref: # Dynamics Theory and Applications, Kane 1985 # Sec. 2.1 ANGULAR VELOCITY A = ReferenceFrame('A') B = ReferenceFrame('B') c11, c12, c13 = dynamicsymbols('C11 C12 C13') c21, c22, c23 = dynamicsymbols('C21 C22 C23') c31, c32, c33 = dynamicsymbols('C31 C32 C33') c11d, c12d, c13d = dynamicsymbols('C11 C12 C13', level=1) c21d, c22d, c23d = dynamicsymbols('C21 C22 C23', level=1) c31d, c32d, c33d = dynamicsymbols('C31 C32 C33', level=1) DCM = Matrix([ [c11, c12, c13], [c21, c22, c23], [c31, c32, c33] ]) B.orient(A, 'DCM', DCM) b1a = (B.x).express(A) b2a = (B.y).express(A) b3a = (B.z).express(A) # Equation (2.1.1) B.set_ang_vel(A, B.x*(dot((b3a).dt(A), B.y)) + B.y*(dot((b1a).dt(A), B.z)) + B.z*(dot((b2a).dt(A), B.x))) # Equation (2.1.21) expr = ( (c12*c13d + c22*c23d + c32*c33d)*B.x + (c13*c11d + c23*c21d + c33*c31d)*B.y + (c11*c12d + c21*c22d + c31*c32d)*B.z) assert B.ang_vel_in(A) - expr == 0 def test_w_diff_dcm2(): q1, q2, q3 = dynamicsymbols('q1:4') N = ReferenceFrame('N') A = N.orientnew('A', 'axis', [q1, N.x]) B = A.orientnew('B', 'axis', [q2, A.y]) C = B.orientnew('C', 'axis', [q3, B.z]) DCM = C.dcm(N).T D = N.orientnew('D', 'DCM', DCM) # Frames D and C are the same ReferenceFrame, # since they have equal DCM respect to frame N. # Therefore, D and C should have same angle velocity in N. assert D.dcm(N) == C.dcm(N) == Matrix([ [cos(q2)*cos(q3), sin(q1)*sin(q2)*cos(q3) + sin(q3)*cos(q1), sin(q1)*sin(q3) - sin(q2)*cos(q1)*cos(q3)], [-sin(q3)*cos(q2), -sin(q1)*sin(q2)*sin(q3) + cos(q1)*cos(q3), sin(q1)*cos(q3) + sin(q2)*sin(q3)*cos(q1)], [sin(q2), -sin(q1)*cos(q2), cos(q1)*cos(q2)]]) assert (D.ang_vel_in(N) - C.ang_vel_in(N)).express(N).simplify() == 0 def test_orientnew_respects_parent_class(): class MyReferenceFrame(ReferenceFrame): pass B = MyReferenceFrame('B') C = B.orientnew('C', 'Axis', [0, B.x]) assert isinstance(C, MyReferenceFrame) def test_orientnew_respects_input_indices(): N = ReferenceFrame('N') q1 = dynamicsymbols('q1') A = N.orientnew('a', 'Axis', [q1, N.z]) #modify default indices: minds = [x+'1' for x in N.indices] B = N.orientnew('b', 'Axis', [q1, N.z], indices=minds) assert N.indices == A.indices assert B.indices == minds def test_orientnew_respects_input_latexs(): N = ReferenceFrame('N') q1 = dynamicsymbols('q1') A = N.orientnew('a', 'Axis', [q1, N.z]) #build default and alternate latex_vecs: def_latex_vecs = [(r"\mathbf{\hat{%s}_%s}" % (A.name.lower(), A.indices[0])), (r"\mathbf{\hat{%s}_%s}" % (A.name.lower(), A.indices[1])), (r"\mathbf{\hat{%s}_%s}" % (A.name.lower(), A.indices[2]))] name = 'b' indices = [x+'1' for x in N.indices] new_latex_vecs = [(r"\mathbf{\hat{%s}_{%s}}" % (name.lower(), indices[0])), (r"\mathbf{\hat{%s}_{%s}}" % (name.lower(), indices[1])), (r"\mathbf{\hat{%s}_{%s}}" % (name.lower(), indices[2]))] B = N.orientnew(name, 'Axis', [q1, N.z], latexs=new_latex_vecs) assert A.latex_vecs == def_latex_vecs assert B.latex_vecs == new_latex_vecs assert B.indices != indices def test_orientnew_respects_input_variables(): N = ReferenceFrame('N') q1 = dynamicsymbols('q1') A = N.orientnew('a', 'Axis', [q1, N.z]) #build non-standard variable names name = 'b' new_variables = ['notb_'+x+'1' for x in N.indices] B = N.orientnew(name, 'Axis', [q1, N.z], variables=new_variables) for j,var in enumerate(A.varlist): assert var.name == A.name + '_' + A.indices[j] for j,var in enumerate(B.varlist): assert var.name == new_variables[j] def test_issue_10348(): u = dynamicsymbols('u:3') I = ReferenceFrame('I') I.orientnew('A', 'space', u, 'XYZ') def test_issue_11503(): A = ReferenceFrame("A") A.orientnew("B", "Axis", [35, A.y]) C = ReferenceFrame("C") A.orient(C, "Axis", [70, C.z]) def test_partial_velocity(): N = ReferenceFrame('N') A = ReferenceFrame('A') u1, u2 = dynamicsymbols('u1, u2') A.set_ang_vel(N, u1 * A.x + u2 * N.y) assert N.partial_velocity(A, u1) == -A.x assert N.partial_velocity(A, u1, u2) == (-A.x, -N.y) assert A.partial_velocity(N, u1) == A.x assert A.partial_velocity(N, u1, u2) == (A.x, N.y) assert N.partial_velocity(N, u1) == 0 assert A.partial_velocity(A, u1) == 0 def test_issue_11498(): A = ReferenceFrame('A') B = ReferenceFrame('B') # Identity transformation A.orient(B, 'DCM', eye(3)) assert A.dcm(B) == Matrix([[1, 0, 0], [0, 1, 0], [0, 0, 1]]) assert B.dcm(A) == Matrix([[1, 0, 0], [0, 1, 0], [0, 0, 1]]) # x -> y # y -> -z # z -> -x A.orient(B, 'DCM', Matrix([[0, 1, 0], [0, 0, -1], [-1, 0, 0]])) assert B.dcm(A) == Matrix([[0, 1, 0], [0, 0, -1], [-1, 0, 0]]) assert A.dcm(B) == Matrix([[0, 0, -1], [1, 0, 0], [0, -1, 0]]) assert B.dcm(A).T == A.dcm(B) def test_reference_frame(): raises(TypeError, lambda: ReferenceFrame(0)) raises(TypeError, lambda: ReferenceFrame('N', 0)) raises(ValueError, lambda: ReferenceFrame('N', [0, 1])) raises(TypeError, lambda: ReferenceFrame('N', [0, 1, 2])) raises(TypeError, lambda: ReferenceFrame('N', ['a', 'b', 'c'], 0)) raises(ValueError, lambda: ReferenceFrame('N', ['a', 'b', 'c'], [0, 1])) raises(TypeError, lambda: ReferenceFrame('N', ['a', 'b', 'c'], [0, 1, 2])) raises(TypeError, lambda: ReferenceFrame('N', ['a', 'b', 'c'], ['a', 'b', 'c'], 0)) raises(ValueError, lambda: ReferenceFrame('N', ['a', 'b', 'c'], ['a', 'b', 'c'], [0, 1])) raises(TypeError, lambda: ReferenceFrame('N', ['a', 'b', 'c'], ['a', 'b', 'c'], [0, 1, 2])) N = ReferenceFrame('N') assert N[0] == CoordinateSym('N_x', N, 0) assert N[1] == CoordinateSym('N_y', N, 1) assert N[2] == CoordinateSym('N_z', N, 2) raises(ValueError, lambda: N[3]) N = ReferenceFrame('N', ['a', 'b', 'c']) assert N['a'] == N.x assert N['b'] == N.y assert N['c'] == N.z raises(ValueError, lambda: N['d']) assert str(N) == 'N' A = ReferenceFrame('A') B = ReferenceFrame('B') q0, q1, q2, q3 = symbols('q0 q1 q2 q3') raises(TypeError, lambda: A.orient(B, 'DCM', 0)) raises(TypeError, lambda: B.orient(N, 'Space', [q1, q2, q3], '222')) raises(TypeError, lambda: B.orient(N, 'Axis', [q1, N.x + 2 * N.y], '222')) raises(TypeError, lambda: B.orient(N, 'Axis', q1)) raises(IndexError, lambda: B.orient(N, 'Axis', [q1])) raises(TypeError, lambda: B.orient(N, 'Quaternion', [q0, q1, q2, q3], '222')) raises(TypeError, lambda: B.orient(N, 'Quaternion', q0)) raises(TypeError, lambda: B.orient(N, 'Quaternion', [q0, q1, q2])) raises(NotImplementedError, lambda: B.orient(N, 'Foo', [q0, q1, q2])) raises(TypeError, lambda: B.orient(N, 'Body', [q1, q2], '232')) raises(TypeError, lambda: B.orient(N, 'Space', [q1, q2], '232')) N.set_ang_acc(B, 0) assert N.ang_acc_in(B) == Vector(0) N.set_ang_vel(B, 0) assert N.ang_vel_in(B) == Vector(0) def test_check_frame(): raises(VectorTypeError, lambda: _check_frame(0)) def test_dcm_diff_16824(): # NOTE : This is a regression test for the bug introduced in PR 14758, # identified in 16824, and solved by PR 16828. # This is the solution to Problem 2.2 on page 264 in Kane & Lenvinson's # 1985 book. q1, q2, q3 = dynamicsymbols('q1:4') s1 = sin(q1) c1 = cos(q1) s2 = sin(q2) c2 = cos(q2) s3 = sin(q3) c3 = cos(q3) dcm = Matrix([[c2*c3, s1*s2*c3 - s3*c1, c1*s2*c3 + s3*s1], [c2*s3, s1*s2*s3 + c3*c1, c1*s2*s3 - c3*s1], [-s2, s1*c2, c1*c2]]) A = ReferenceFrame('A') B = ReferenceFrame('B') B.orient(A, 'DCM', dcm) AwB = B.ang_vel_in(A) alpha2 = s3*c2*q1.diff() + c3*q2.diff() beta2 = s1*c2*q3.diff() + c1*q2.diff() assert simplify(AwB.dot(A.y) - alpha2) == 0 assert simplify(AwB.dot(B.y) - beta2) == 0 def test_orient_explicit(): A = ReferenceFrame('A') B = ReferenceFrame('B') A.orient_explicit(B, eye(3)) assert A.dcm(B) == Matrix([[1, 0, 0], [0, 1, 0], [0, 0, 1]]) def test_orient_axis(): A = ReferenceFrame('A') B = ReferenceFrame('B') assert A.orient_axis(B,-B.x, 1) == A.orient_axis(B, B.x, -1) def test_orient_body(): A = ReferenceFrame('A') B = ReferenceFrame('B') B.orient_body_fixed(A, (1,1,0), 'XYX') assert B.dcm(A) == Matrix([[cos(1), sin(1)**2, -sin(1)*cos(1)], [0, cos(1), sin(1)], [sin(1), -sin(1)*cos(1), cos(1)**2]]) def test_orient_space(): A = ReferenceFrame('A') B = ReferenceFrame('B') B.orient_space_fixed(A, (0,0,0), '123') assert B.dcm(A) == Matrix([[1, 0, 0], [0, 1, 0], [0, 0, 1]]) def test_orient_quaternion(): A = ReferenceFrame('A') B = ReferenceFrame('B') B.orient_quaternion(A, (0,0,0,0)) assert B.dcm(A) == Matrix([[0, 0, 0], [0, 0, 0], [0, 0, 0]]) def test_looped_frame_warning(): A = ReferenceFrame('A') B = ReferenceFrame('B') C = ReferenceFrame('C') a, b, c = symbols('a b c') B.orient_axis(A, A.x, a) C.orient_axis(B, B.x, b) with warnings.catch_warnings(record = True) as w: warnings.simplefilter("always") A.orient_axis(C, C.x, c) assert issubclass(w[-1].category, UserWarning) assert 'Loops are defined among the orientation of frames. ' + \ 'This is likely not desired and may cause errors in your calculations.' in str(w[-1].message) def test_frame_dict(): A = ReferenceFrame('A') B = ReferenceFrame('B') C = ReferenceFrame('C') a, b, c = symbols('a b c') B.orient_axis(A, A.x, a) assert A._dcm_dict == {B: Matrix([[1, 0, 0],[0, cos(a), -sin(a)],[0, sin(a), cos(a)]])} assert B._dcm_dict == {A: Matrix([[1, 0, 0],[0, cos(a), sin(a)],[0, -sin(a), cos(a)]])} assert C._dcm_dict == {} B.orient_axis(C, C.x, b) # Previous relation is not wiped assert A._dcm_dict == {B: Matrix([[1, 0, 0],[0, cos(a), -sin(a)],[0, sin(a), cos(a)]])} assert B._dcm_dict == {A: Matrix([[1, 0, 0],[0, cos(a), sin(a)],[0, -sin(a), cos(a)]]), \ C: Matrix([[1, 0, 0],[0, cos(b), sin(b)],[0, -sin(b), cos(b)]])} assert C._dcm_dict == {B: Matrix([[1, 0, 0],[0, cos(b), -sin(b)],[0, sin(b), cos(b)]])} A.orient_axis(B, B.x, c) # Previous relation is updated assert B._dcm_dict == {C: Matrix([[1, 0, 0],[0, cos(b), sin(b)],[0, -sin(b), cos(b)]]),\ A: Matrix([[1, 0, 0],[0, cos(c), -sin(c)],[0, sin(c), cos(c)]])} assert A._dcm_dict == {B: Matrix([[1, 0, 0],[0, cos(c), sin(c)],[0, -sin(c), cos(c)]])} assert C._dcm_dict == {B: Matrix([[1, 0, 0],[0, cos(b), -sin(b)],[0, sin(b), cos(b)]])} def test_dcm_cache_dict(): A = ReferenceFrame('A') B = ReferenceFrame('B') C = ReferenceFrame('C') D = ReferenceFrame('D') a, b, c = symbols('a b c') B.orient_axis(A, A.x, a) C.orient_axis(B, B.x, b) D.orient_axis(C, C.x, c) assert D._dcm_dict == {C: Matrix([[1, 0, 0],[0, cos(c), sin(c)],[0, -sin(c), cos(c)]])} assert C._dcm_dict == {B: Matrix([[1, 0, 0],[0, cos(b), sin(b)],[0, -sin(b), cos(b)]]), \ D: Matrix([[1, 0, 0],[0, cos(c), -sin(c)],[0, sin(c), cos(c)]])} assert B._dcm_dict == {A: Matrix([[1, 0, 0],[0, cos(a), sin(a)],[0, -sin(a), cos(a)]]), \ C: Matrix([[1, 0, 0],[0, cos(b), -sin(b)],[0, sin(b), cos(b)]])} assert A._dcm_dict == {B: Matrix([[1, 0, 0],[0, cos(a), -sin(a)],[0, sin(a), cos(a)]])} assert D._dcm_dict == D._dcm_cache D.dcm(A) # Check calculated dcm relation is stored in _dcm_cache and not in _dcm_dict assert list(A._dcm_cache.keys()) == [A, B, D] assert list(D._dcm_cache.keys()) == [C, A] assert list(A._dcm_dict.keys()) == [B] assert list(D._dcm_dict.keys()) == [C] assert A._dcm_dict != A._dcm_cache A.orient_axis(B, B.x, b) # _dcm_cache of A is wiped out and new relation is stored. assert A._dcm_dict == {B: Matrix([[1, 0, 0],[0, cos(b), sin(b)],[0, -sin(b), cos(b)]])} assert A._dcm_dict == A._dcm_cache assert B._dcm_dict == {C: Matrix([[1, 0, 0],[0, cos(b), -sin(b)],[0, sin(b), cos(b)]]), \ A: Matrix([[1, 0, 0],[0, cos(b), -sin(b)],[0, sin(b), cos(b)]])}
774ef2f8583c73b6ef5f77c18ad6343a24693c02cc848960086bc0aabcd6d963
from sympy.assumptions.cnf import EncodedCNF def minisat22_satisfiable(expr, all_models=False, minimal=False): if not isinstance(expr, EncodedCNF): exprs = EncodedCNF() exprs.add_prop(expr) expr = exprs from pysat.solvers import Minisat22 # Return UNSAT when False (encoded as 0) is present in the CNF if {0} in expr.data: if all_models: return (f for f in [False]) return False r = Minisat22(expr.data) if minimal: r.set_phases([-(i+1) for i in range(r.nof_vars())]) if not r.solve(): return False if not all_models: return {expr.symbols[abs(lit) - 1]: lit > 0 for lit in r.get_model()} else: # Make solutions sympy compatible by creating a generator def _gen(results): satisfiable = False while results.solve(): sol = results.get_model() yield {expr.symbols[abs(lit) - 1]: lit > 0 for lit in sol} if minimal: results.add_clause([-i for i in sol if i>0]) else: results.add_clause([-i for i in sol]) satisfiable = True if not satisfiable: yield False raise StopIteration return _gen(r)
1aa3a6f57437bbc4010f8d4c7d7ffb1582ecf56d41bb3a7312299e6316ffa00e
from sympy.assumptions.ask import Q from sympy.assumptions.refine import refine from sympy.core.numbers import oo from sympy.core.relational import Equality, Eq, Ne from sympy.core.singleton import S from sympy.core.symbol import (Dummy, symbols) from sympy.functions import Piecewise from sympy.functions.elementary.miscellaneous import Max, Min from sympy.functions.elementary.trigonometric import sin from sympy.sets.sets import (EmptySet, Interval, Union) from sympy.simplify.simplify import simplify from sympy.logic.boolalg import ( And, Boolean, Equivalent, ITE, Implies, Nand, Nor, Not, Or, POSform, SOPform, Xor, Xnor, conjuncts, disjuncts, distribute_or_over_and, distribute_and_over_or, eliminate_implications, is_nnf, is_cnf, is_dnf, simplify_logic, to_nnf, to_cnf, to_dnf, to_int_repr, bool_map, true, false, BooleanAtom, is_literal, term_to_integer, integer_to_term, truth_table, as_Boolean, to_anf, is_anf, distribute_xor_over_and, anf_coeffs, ANFform, bool_minterm, bool_maxterm, bool_monomial, _check_pair, _convert_to_varsSOP, _convert_to_varsPOS, Exclusive,) from sympy.assumptions.cnf import CNF from sympy.testing.pytest import raises, XFAIL, slow from sympy.utilities.iterables import cartes from itertools import combinations, permutations A, B, C, D = symbols('A:D') a, b, c, d, e, w, x, y, z = symbols('a:e w:z') def test_overloading(): """Test that |, & are overloaded as expected""" assert A & B == And(A, B) assert A | B == Or(A, B) assert (A & B) | C == Or(And(A, B), C) assert A >> B == Implies(A, B) assert A << B == Implies(B, A) assert ~A == Not(A) assert A ^ B == Xor(A, B) def test_And(): assert And() is true assert And(A) == A assert And(True) is true assert And(False) is false assert And(True, True) is true assert And(True, False) is false assert And(False, False) is false assert And(True, A) == A assert And(False, A) is false assert And(True, True, True) is true assert And(True, True, A) == A assert And(True, False, A) is false assert And(1, A) == A raises(TypeError, lambda: And(2, A)) raises(TypeError, lambda: And(A < 2, A)) assert And(A < 1, A >= 1) is false e = A > 1 assert And(e, e.canonical) == e.canonical g, l, ge, le = A > B, B < A, A >= B, B <= A assert And(g, l, ge, le) == And(ge, g) assert {And(*i) for i in permutations((l,g,le,ge))} == {And(ge, g)} assert And(And(Eq(a, 0), Eq(b, 0)), And(Ne(a, 0), Eq(c, 0))) is false def test_Or(): assert Or() is false assert Or(A) == A assert Or(True) is true assert Or(False) is false assert Or(True, True) is true assert Or(True, False) is true assert Or(False, False) is false assert Or(True, A) is true assert Or(False, A) == A assert Or(True, False, False) is true assert Or(True, False, A) is true assert Or(False, False, A) == A assert Or(1, A) is true raises(TypeError, lambda: Or(2, A)) raises(TypeError, lambda: Or(A < 2, A)) assert Or(A < 1, A >= 1) is true e = A > 1 assert Or(e, e.canonical) == e g, l, ge, le = A > B, B < A, A >= B, B <= A assert Or(g, l, ge, le) == Or(g, ge) def test_Xor(): assert Xor() is false assert Xor(A) == A assert Xor(A, A) is false assert Xor(True, A, A) is true assert Xor(A, A, A, A, A) == A assert Xor(True, False, False, A, B) == ~Xor(A, B) assert Xor(True) is true assert Xor(False) is false assert Xor(True, True) is false assert Xor(True, False) is true assert Xor(False, False) is false assert Xor(True, A) == ~A assert Xor(False, A) == A assert Xor(True, False, False) is true assert Xor(True, False, A) == ~A assert Xor(False, False, A) == A assert isinstance(Xor(A, B), Xor) assert Xor(A, B, Xor(C, D)) == Xor(A, B, C, D) assert Xor(A, B, Xor(B, C)) == Xor(A, C) assert Xor(A < 1, A >= 1, B) == Xor(0, 1, B) == Xor(1, 0, B) e = A > 1 assert Xor(e, e.canonical) == Xor(0, 0) == Xor(1, 1) def test_rewrite_as_And(): expr = x ^ y assert expr.rewrite(And) == (x | y) & (~x | ~y) def test_rewrite_as_Or(): expr = x ^ y assert expr.rewrite(Or) == (x & ~y) | (y & ~x) def test_rewrite_as_Nand(): expr = (y & z) | (z & ~w) assert expr.rewrite(Nand) == ~(~(y & z) & ~(z & ~w)) def test_rewrite_as_Nor(): expr = z & (y | ~w) assert expr.rewrite(Nor) == ~(~z | ~(y | ~w)) def test_Not(): raises(TypeError, lambda: Not(True, False)) assert Not(True) is false assert Not(False) is true assert Not(0) is true assert Not(1) is false assert Not(2) is false def test_Nand(): assert Nand() is false assert Nand(A) == ~A assert Nand(True) is false assert Nand(False) is true assert Nand(True, True) is false assert Nand(True, False) is true assert Nand(False, False) is true assert Nand(True, A) == ~A assert Nand(False, A) is true assert Nand(True, True, True) is false assert Nand(True, True, A) == ~A assert Nand(True, False, A) is true def test_Nor(): assert Nor() is true assert Nor(A) == ~A assert Nor(True) is false assert Nor(False) is true assert Nor(True, True) is false assert Nor(True, False) is false assert Nor(False, False) is true assert Nor(True, A) is false assert Nor(False, A) == ~A assert Nor(True, True, True) is false assert Nor(True, True, A) is false assert Nor(True, False, A) is false def test_Xnor(): assert Xnor() is true assert Xnor(A) == ~A assert Xnor(A, A) is true assert Xnor(True, A, A) is false assert Xnor(A, A, A, A, A) == ~A assert Xnor(True) is false assert Xnor(False) is true assert Xnor(True, True) is true assert Xnor(True, False) is false assert Xnor(False, False) is true assert Xnor(True, A) == A assert Xnor(False, A) == ~A assert Xnor(True, False, False) is false assert Xnor(True, False, A) == A assert Xnor(False, False, A) == ~A def test_Implies(): raises(ValueError, lambda: Implies(A, B, C)) assert Implies(True, True) is true assert Implies(True, False) is false assert Implies(False, True) is true assert Implies(False, False) is true assert Implies(0, A) is true assert Implies(1, 1) is true assert Implies(1, 0) is false assert A >> B == B << A assert (A < 1) >> (A >= 1) == (A >= 1) assert (A < 1) >> (S.One > A) is true assert A >> A is true def test_Equivalent(): assert Equivalent(A, B) == Equivalent(B, A) == Equivalent(A, B, A) assert Equivalent() is true assert Equivalent(A, A) == Equivalent(A) is true assert Equivalent(True, True) == Equivalent(False, False) is true assert Equivalent(True, False) == Equivalent(False, True) is false assert Equivalent(A, True) == A assert Equivalent(A, False) == Not(A) assert Equivalent(A, B, True) == A & B assert Equivalent(A, B, False) == ~A & ~B assert Equivalent(1, A) == A assert Equivalent(0, A) == Not(A) assert Equivalent(A, Equivalent(B, C)) != Equivalent(Equivalent(A, B), C) assert Equivalent(A < 1, A >= 1) is false assert Equivalent(A < 1, A >= 1, 0) is false assert Equivalent(A < 1, A >= 1, 1) is false assert Equivalent(A < 1, S.One > A) == Equivalent(1, 1) == Equivalent(0, 0) assert Equivalent(Equality(A, B), Equality(B, A)) is true def test_Exclusive(): assert Exclusive(False, False, False) is true assert Exclusive(True, False, False) is true assert Exclusive(True, True, False) is false assert Exclusive(True, True, True) is false def test_equals(): assert Not(Or(A, B)).equals(And(Not(A), Not(B))) is True assert Equivalent(A, B).equals((A >> B) & (B >> A)) is True assert ((A | ~B) & (~A | B)).equals((~A & ~B) | (A & B)) is True assert (A >> B).equals(~A >> ~B) is False assert (A >> (B >> A)).equals(A >> (C >> A)) is False raises(NotImplementedError, lambda: (A & B).equals(A > B)) def test_simplification(): """ Test working of simplification methods. """ set1 = [[0, 0, 1], [0, 1, 1], [1, 0, 0], [1, 1, 0]] set2 = [[0, 0, 0], [0, 1, 0], [1, 0, 1], [1, 1, 1]] assert SOPform([x, y, z], set1) == Or(And(Not(x), z), And(Not(z), x)) assert Not(SOPform([x, y, z], set2)) == \ Not(Or(And(Not(x), Not(z)), And(x, z))) assert POSform([x, y, z], set1 + set2) is true assert SOPform([x, y, z], set1 + set2) is true assert SOPform([Dummy(), Dummy(), Dummy()], set1 + set2) is true minterms = [[0, 0, 0, 1], [0, 0, 1, 1], [0, 1, 1, 1], [1, 0, 1, 1], [1, 1, 1, 1]] dontcares = [[0, 0, 0, 0], [0, 0, 1, 0], [0, 1, 0, 1]] assert ( SOPform([w, x, y, z], minterms, dontcares) == Or(And(y, z), And(Not(w), Not(x)))) assert POSform([w, x, y, z], minterms, dontcares) == And(Or(Not(w), y), z) minterms = [1, 3, 7, 11, 15] dontcares = [0, 2, 5] assert ( SOPform([w, x, y, z], minterms, dontcares) == Or(And(y, z), And(Not(w), Not(x)))) assert POSform([w, x, y, z], minterms, dontcares) == And(Or(Not(w), y), z) minterms = [1, [0, 0, 1, 1], 7, [1, 0, 1, 1], [1, 1, 1, 1]] dontcares = [0, [0, 0, 1, 0], 5] assert ( SOPform([w, x, y, z], minterms, dontcares) == Or(And(y, z), And(Not(w), Not(x)))) assert POSform([w, x, y, z], minterms, dontcares) == And(Or(Not(w), y), z) minterms = [1, {y: 1, z: 1}] dontcares = [0, [0, 0, 1, 0], 5] assert ( SOPform([w, x, y, z], minterms, dontcares) == Or(And(y, z), And(Not(w), Not(x)))) assert POSform([w, x, y, z], minterms, dontcares) == And(Or(Not(w), y), z) minterms = [{y: 1, z: 1}, 1] dontcares = [[0, 0, 0, 0]] minterms = [[0, 0, 0]] raises(ValueError, lambda: SOPform([w, x, y, z], minterms)) raises(ValueError, lambda: POSform([w, x, y, z], minterms)) raises(TypeError, lambda: POSform([w, x, y, z], ["abcdefg"])) # test simplification ans = And(A, Or(B, C)) assert simplify_logic(A & (B | C)) == ans assert simplify_logic((A & B) | (A & C)) == ans assert simplify_logic(Implies(A, B)) == Or(Not(A), B) assert simplify_logic(Equivalent(A, B)) == \ Or(And(A, B), And(Not(A), Not(B))) assert simplify_logic(And(Equality(A, 2), C)) == And(Equality(A, 2), C) assert simplify_logic(And(Equality(A, 2), A)) is S.false assert simplify_logic(And(Equality(A, 2), A)) == And(Equality(A, 2), A) assert simplify_logic(And(Equality(A, B), C)) == And(Equality(A, B), C) assert simplify_logic(Or(And(Equality(A, 3), B), And(Equality(A, 3), C))) \ == And(Equality(A, 3), Or(B, C)) b = (~x & ~y & ~z) | (~x & ~y & z) e = And(A, b) assert simplify_logic(e) == A & ~x & ~y raises(ValueError, lambda: simplify_logic(A & (B | C), form='blabla')) # Check that expressions with nine variables or more are not simplified # (without the force-flag) a, b, c, d, e, f, g, h, j = symbols('a b c d e f g h j') expr = a & b & c & d & e & f & g & h & j | \ a & b & c & d & e & f & g & h & ~j # This expression can be simplified to get rid of the j variables assert simplify_logic(expr) == expr # check input ans = SOPform([x, y], [[1, 0]]) assert SOPform([x, y], [[1, 0]]) == ans assert POSform([x, y], [[1, 0]]) == ans raises(ValueError, lambda: SOPform([x], [[1]], [[1]])) assert SOPform([x], [[1]], [[0]]) is true assert SOPform([x], [[0]], [[1]]) is true assert SOPform([x], [], []) is false raises(ValueError, lambda: POSform([x], [[1]], [[1]])) assert POSform([x], [[1]], [[0]]) is true assert POSform([x], [[0]], [[1]]) is true assert POSform([x], [], []) is false # check working of simplify assert simplify((A & B) | (A & C)) == And(A, Or(B, C)) assert simplify(And(x, Not(x))) == False assert simplify(Or(x, Not(x))) == True assert simplify(And(Eq(x, 0), Eq(x, y))) == And(Eq(x, 0), Eq(y, 0)) assert And(Eq(x - 1, 0), Eq(x, y)).simplify() == And(Eq(x, 1), Eq(y, 1)) assert And(Ne(x - 1, 0), Ne(x, y)).simplify() == And(Ne(x, 1), Ne(x, y)) assert And(Eq(x - 1, 0), Ne(x, y)).simplify() == And(Eq(x, 1), Ne(y, 1)) assert And(Eq(x - 1, 0), Eq(x, z + y), Eq(y + x, 0)).simplify( ) == And(Eq(x, 1), Eq(y, -1), Eq(z, 2)) assert And(Eq(x - 1, 0), Eq(x + 2, 3)).simplify() == Eq(x, 1) assert And(Ne(x - 1, 0), Ne(x + 2, 3)).simplify() == Ne(x, 1) assert And(Eq(x - 1, 0), Eq(x + 2, 2)).simplify() == False assert And(Ne(x - 1, 0), Ne(x + 2, 2)).simplify( ) == And(Ne(x, 1), Ne(x, 0)) def test_bool_map(): """ Test working of bool_map function. """ minterms = [[0, 0, 0, 1], [0, 0, 1, 1], [0, 1, 1, 1], [1, 0, 1, 1], [1, 1, 1, 1]] assert bool_map(Not(Not(a)), a) == (a, {a: a}) assert bool_map(SOPform([w, x, y, z], minterms), POSform([w, x, y, z], minterms)) == \ (And(Or(Not(w), y), Or(Not(x), y), z), {x: x, w: w, z: z, y: y}) assert bool_map(SOPform([x, z, y], [[1, 0, 1]]), SOPform([a, b, c], [[1, 0, 1]])) != False function1 = SOPform([x, z, y], [[1, 0, 1], [0, 0, 1]]) function2 = SOPform([a, b, c], [[1, 0, 1], [1, 0, 0]]) assert bool_map(function1, function2) == \ (function1, {y: a, z: b}) assert bool_map(Xor(x, y), ~Xor(x, y)) == False assert bool_map(And(x, y), Or(x, y)) is None assert bool_map(And(x, y), And(x, y, z)) is None # issue 16179 assert bool_map(Xor(x, y, z), ~Xor(x, y, z)) == False assert bool_map(Xor(a, x, y, z), ~Xor(a, x, y, z)) == False def test_bool_symbol(): """Test that mixing symbols with boolean values works as expected""" assert And(A, True) == A assert And(A, True, True) == A assert And(A, False) is false assert And(A, True, False) is false assert Or(A, True) is true assert Or(A, False) == A def test_is_boolean(): assert isinstance(True, Boolean) is False assert isinstance(true, Boolean) is True assert 1 == True assert 1 != true assert (1 == true) is False assert 0 == False assert 0 != false assert (0 == false) is False assert true.is_Boolean is True assert (A & B).is_Boolean assert (A | B).is_Boolean assert (~A).is_Boolean assert (A ^ B).is_Boolean assert A.is_Boolean != isinstance(A, Boolean) assert isinstance(A, Boolean) def test_subs(): assert (A & B).subs(A, True) == B assert (A & B).subs(A, False) is false assert (A & B).subs(B, True) == A assert (A & B).subs(B, False) is false assert (A & B).subs({A: True, B: True}) is true assert (A | B).subs(A, True) is true assert (A | B).subs(A, False) == B assert (A | B).subs(B, True) is true assert (A | B).subs(B, False) == A assert (A | B).subs({A: True, B: True}) is true """ we test for axioms of boolean algebra see https://en.wikipedia.org/wiki/Boolean_algebra_(structure) """ def test_commutative(): """Test for commutativity of And and Or""" A, B = map(Boolean, symbols('A,B')) assert A & B == B & A assert A | B == B | A def test_and_associativity(): """Test for associativity of And""" assert (A & B) & C == A & (B & C) def test_or_assicativity(): assert ((A | B) | C) == (A | (B | C)) def test_double_negation(): a = Boolean() assert ~(~a) == a # test methods def test_eliminate_implications(): assert eliminate_implications(Implies(A, B, evaluate=False)) == (~A) | B assert eliminate_implications( A >> (C >> Not(B))) == Or(Or(Not(B), Not(C)), Not(A)) assert eliminate_implications(Equivalent(A, B, C, D)) == \ (~A | B) & (~B | C) & (~C | D) & (~D | A) def test_conjuncts(): assert conjuncts(A & B & C) == {A, B, C} assert conjuncts((A | B) & C) == {A | B, C} assert conjuncts(A) == {A} assert conjuncts(True) == {True} assert conjuncts(False) == {False} def test_disjuncts(): assert disjuncts(A | B | C) == {A, B, C} assert disjuncts((A | B) & C) == {(A | B) & C} assert disjuncts(A) == {A} assert disjuncts(True) == {True} assert disjuncts(False) == {False} def test_distribute(): assert distribute_and_over_or(Or(And(A, B), C)) == And(Or(A, C), Or(B, C)) assert distribute_or_over_and(And(A, Or(B, C))) == Or(And(A, B), And(A, C)) assert distribute_xor_over_and(And(A, Xor(B, C))) == Xor(And(A, B), And(A, C)) def test_to_anf(): x, y, z = symbols('x,y,z') assert to_anf(And(x, y)) == And(x, y) assert to_anf(Or(x, y)) == Xor(x, y, And(x, y)) assert to_anf(Or(Implies(x, y), And(x, y), y)) == \ Xor(x, True, x & y, remove_true=False) assert to_anf(Or(Nand(x, y), Nor(x, y), Xnor(x, y), Implies(x, y))) == True assert to_anf(Or(x, Not(y), Nor(x,z), And(x, y), Nand(y, z))) == \ Xor(True, And(y, z), And(x, y, z), remove_true=False) assert to_anf(Xor(x, y)) == Xor(x, y) assert to_anf(Not(x)) == Xor(x, True, remove_true=False) assert to_anf(Nand(x, y)) == Xor(True, And(x, y), remove_true=False) assert to_anf(Nor(x, y)) == Xor(x, y, True, And(x, y), remove_true=False) assert to_anf(Implies(x, y)) == Xor(x, True, And(x, y), remove_true=False) assert to_anf(Equivalent(x, y)) == Xor(x, y, True, remove_true=False) assert to_anf(Nand(x | y, x >> y), deep=False) == \ Xor(True, And(Or(x, y), Implies(x, y)), remove_true=False) assert to_anf(Nor(x ^ y, x & y), deep=False) == \ Xor(True, Or(Xor(x, y), And(x, y)), remove_true=False) def test_to_nnf(): assert to_nnf(true) is true assert to_nnf(false) is false assert to_nnf(A) == A assert to_nnf(A | ~A | B) is true assert to_nnf(A & ~A & B) is false assert to_nnf(A >> B) == ~A | B assert to_nnf(Equivalent(A, B, C)) == (~A | B) & (~B | C) & (~C | A) assert to_nnf(A ^ B ^ C) == \ (A | B | C) & (~A | ~B | C) & (A | ~B | ~C) & (~A | B | ~C) assert to_nnf(ITE(A, B, C)) == (~A | B) & (A | C) assert to_nnf(Not(A | B | C)) == ~A & ~B & ~C assert to_nnf(Not(A & B & C)) == ~A | ~B | ~C assert to_nnf(Not(A >> B)) == A & ~B assert to_nnf(Not(Equivalent(A, B, C))) == And(Or(A, B, C), Or(~A, ~B, ~C)) assert to_nnf(Not(A ^ B ^ C)) == \ (~A | B | C) & (A | ~B | C) & (A | B | ~C) & (~A | ~B | ~C) assert to_nnf(Not(ITE(A, B, C))) == (~A | ~B) & (A | ~C) assert to_nnf((A >> B) ^ (B >> A)) == (A & ~B) | (~A & B) assert to_nnf((A >> B) ^ (B >> A), False) == \ (~A | ~B | A | B) & ((A & ~B) | (~A & B)) assert ITE(A, 1, 0).to_nnf() == A assert ITE(A, 0, 1).to_nnf() == ~A # although ITE can hold non-Boolean, it will complain if # an attempt is made to convert the ITE to Boolean nnf raises(TypeError, lambda: ITE(A < 1, [1], B).to_nnf()) def test_to_cnf(): assert to_cnf(~(B | C)) == And(Not(B), Not(C)) assert to_cnf((A & B) | C) == And(Or(A, C), Or(B, C)) assert to_cnf(A >> B) == (~A) | B assert to_cnf(A >> (B & C)) == (~A | B) & (~A | C) assert to_cnf(A & (B | C) | ~A & (B | C), True) == B | C assert to_cnf(A & B) == And(A, B) assert to_cnf(Equivalent(A, B)) == And(Or(A, Not(B)), Or(B, Not(A))) assert to_cnf(Equivalent(A, B & C)) == \ (~A | B) & (~A | C) & (~B | ~C | A) assert to_cnf(Equivalent(A, B | C), True) == \ And(Or(Not(B), A), Or(Not(C), A), Or(B, C, Not(A))) assert to_cnf(A + 1) == A + 1 def test_issue_18904(): x1, x2, x3, x4, x5, x6, x7, x8, x9, x10, x11, x12, x13, x14, x15 = symbols('x1:16') eq = (( x1 & x2 & x3 & x4 & x5 & x6 & x7 & x8 & x9 ) | ( x1 & x2 & x3 & x4 & x5 & x6 & x7 & x10 & x9 ) | ( x1 & x11 & x3 & x12 & x5 & x13 & x14 & x15 & x9 )) assert is_cnf(to_cnf(eq)) raises(ValueError, lambda: to_cnf(eq, simplify=True)) for f, t in zip((And, Or), (to_cnf, to_dnf)): eq = f(x1, x2, x3, x4, x5, x6, x7, x8, x9) raises(ValueError, lambda: to_cnf(eq, simplify=True)) assert t(eq, simplify=True, force=True) == eq def test_issue_9949(): assert is_cnf(to_cnf((b > -5) | (a > 2) & (a < 4))) def test_to_CNF(): assert CNF.CNF_to_cnf(CNF.to_CNF(~(B | C))) == to_cnf(~(B | C)) assert CNF.CNF_to_cnf(CNF.to_CNF((A & B) | C)) == to_cnf((A & B) | C) assert CNF.CNF_to_cnf(CNF.to_CNF(A >> B)) == to_cnf(A >> B) assert CNF.CNF_to_cnf(CNF.to_CNF(A >> (B & C))) == to_cnf(A >> (B & C)) assert CNF.CNF_to_cnf(CNF.to_CNF(A & (B | C) | ~A & (B | C))) == to_cnf(A & (B | C) | ~A & (B | C)) assert CNF.CNF_to_cnf(CNF.to_CNF(A & B)) == to_cnf(A & B) def test_to_dnf(): assert to_dnf(~(B | C)) == And(Not(B), Not(C)) assert to_dnf(A & (B | C)) == Or(And(A, B), And(A, C)) assert to_dnf(A >> B) == (~A) | B assert to_dnf(A >> (B & C)) == (~A) | (B & C) assert to_dnf(A | B) == A | B assert to_dnf(Equivalent(A, B), True) == \ Or(And(A, B), And(Not(A), Not(B))) assert to_dnf(Equivalent(A, B & C), True) == \ Or(And(A, B, C), And(Not(A), Not(B)), And(Not(A), Not(C))) assert to_dnf(A + 1) == A + 1 def test_to_int_repr(): x, y, z = map(Boolean, symbols('x,y,z')) def sorted_recursive(arg): try: return sorted(sorted_recursive(x) for x in arg) except TypeError: # arg is not a sequence return arg assert sorted_recursive(to_int_repr([x | y, z | x], [x, y, z])) == \ sorted_recursive([[1, 2], [1, 3]]) assert sorted_recursive(to_int_repr([x | y, z | ~x], [x, y, z])) == \ sorted_recursive([[1, 2], [3, -1]]) def test_is_anf(): x, y = symbols('x,y') assert is_anf(true) is True assert is_anf(false) is True assert is_anf(x) is True assert is_anf(And(x, y)) is True assert is_anf(Xor(x, y, And(x, y))) is True assert is_anf(Xor(x, y, Or(x, y))) is False assert is_anf(Xor(Not(x), y)) is False def test_is_nnf(): assert is_nnf(true) is True assert is_nnf(A) is True assert is_nnf(~A) is True assert is_nnf(A & B) is True assert is_nnf((A & B) | (~A & A) | (~B & B) | (~A & ~B), False) is True assert is_nnf((A | B) & (~A | ~B)) is True assert is_nnf(Not(Or(A, B))) is False assert is_nnf(A ^ B) is False assert is_nnf((A & B) | (~A & A) | (~B & B) | (~A & ~B), True) is False def test_is_cnf(): assert is_cnf(x) is True assert is_cnf(x | y | z) is True assert is_cnf(x & y & z) is True assert is_cnf((x | y) & z) is True assert is_cnf((x & y) | z) is False assert is_cnf(~(x & y) | z) is False def test_is_dnf(): assert is_dnf(x) is True assert is_dnf(x | y | z) is True assert is_dnf(x & y & z) is True assert is_dnf((x & y) | z) is True assert is_dnf((x | y) & z) is False assert is_dnf(~(x | y) & z) is False def test_ITE(): A, B, C = symbols('A:C') assert ITE(True, False, True) is false assert ITE(True, True, False) is true assert ITE(False, True, False) is false assert ITE(False, False, True) is true assert isinstance(ITE(A, B, C), ITE) A = True assert ITE(A, B, C) == B A = False assert ITE(A, B, C) == C B = True assert ITE(And(A, B), B, C) == C assert ITE(Or(A, False), And(B, True), False) is false assert ITE(x, A, B) == Not(x) assert ITE(x, B, A) == x assert ITE(1, x, y) == x assert ITE(0, x, y) == y raises(TypeError, lambda: ITE(2, x, y)) raises(TypeError, lambda: ITE(1, [], y)) raises(TypeError, lambda: ITE(1, (), y)) raises(TypeError, lambda: ITE(1, y, [])) assert ITE(1, 1, 1) is S.true assert isinstance(ITE(1, 1, 1, evaluate=False), ITE) raises(TypeError, lambda: ITE(x > 1, y, x)) assert ITE(Eq(x, True), y, x) == ITE(x, y, x) assert ITE(Eq(x, False), y, x) == ITE(~x, y, x) assert ITE(Ne(x, True), y, x) == ITE(~x, y, x) assert ITE(Ne(x, False), y, x) == ITE(x, y, x) assert ITE(Eq(S. true, x), y, x) == ITE(x, y, x) assert ITE(Eq(S.false, x), y, x) == ITE(~x, y, x) assert ITE(Ne(S.true, x), y, x) == ITE(~x, y, x) assert ITE(Ne(S.false, x), y, x) == ITE(x, y, x) # 0 and 1 in the context are not treated as True/False # so the equality must always be False since dissimilar # objects cannot be equal assert ITE(Eq(x, 0), y, x) == x assert ITE(Eq(x, 1), y, x) == x assert ITE(Ne(x, 0), y, x) == y assert ITE(Ne(x, 1), y, x) == y assert ITE(Eq(x, 0), y, z).subs(x, 0) == y assert ITE(Eq(x, 0), y, z).subs(x, 1) == z raises(ValueError, lambda: ITE(x > 1, y, x, z)) def test_is_literal(): assert is_literal(True) is True assert is_literal(False) is True assert is_literal(A) is True assert is_literal(~A) is True assert is_literal(Or(A, B)) is False assert is_literal(Q.zero(A)) is True assert is_literal(Not(Q.zero(A))) is True assert is_literal(Or(A, B)) is False assert is_literal(And(Q.zero(A), Q.zero(B))) is False assert is_literal(x < 3) assert not is_literal(x + y < 3) def test_operators(): # Mostly test __and__, __rand__, and so on assert True & A == A & True == A assert False & A == A & False == False assert A & B == And(A, B) assert True | A == A | True == True assert False | A == A | False == A assert A | B == Or(A, B) assert ~A == Not(A) assert True >> A == A << True == A assert False >> A == A << False == True assert A >> True == True << A == True assert A >> False == False << A == ~A assert A >> B == B << A == Implies(A, B) assert True ^ A == A ^ True == ~A assert False ^ A == A ^ False == A assert A ^ B == Xor(A, B) def test_true_false(): assert true is S.true assert false is S.false assert true is not True assert false is not False assert true assert not false assert true == True assert false == False assert not (true == False) assert not (false == True) assert not (true == false) assert hash(true) == hash(True) assert hash(false) == hash(False) assert len({true, True}) == len({false, False}) == 1 assert isinstance(true, BooleanAtom) assert isinstance(false, BooleanAtom) # We don't want to subclass from bool, because bool subclasses from # int. But operators like &, |, ^, <<, >>, and ~ act differently on 0 and # 1 then we want them to on true and false. See the docstrings of the # various And, Or, etc. functions for examples. assert not isinstance(true, bool) assert not isinstance(false, bool) # Note: using 'is' comparison is important here. We want these to return # true and false, not True and False assert Not(true) is false assert Not(True) is false assert Not(false) is true assert Not(False) is true assert ~true is false assert ~false is true for T, F in cartes([True, true], [False, false]): assert And(T, F) is false assert And(F, T) is false assert And(F, F) is false assert And(T, T) is true assert And(T, x) == x assert And(F, x) is false if not (T is True and F is False): assert T & F is false assert F & T is false if F is not False: assert F & F is false if T is not True: assert T & T is true assert Or(T, F) is true assert Or(F, T) is true assert Or(F, F) is false assert Or(T, T) is true assert Or(T, x) is true assert Or(F, x) == x if not (T is True and F is False): assert T | F is true assert F | T is true if F is not False: assert F | F is false if T is not True: assert T | T is true assert Xor(T, F) is true assert Xor(F, T) is true assert Xor(F, F) is false assert Xor(T, T) is false assert Xor(T, x) == ~x assert Xor(F, x) == x if not (T is True and F is False): assert T ^ F is true assert F ^ T is true if F is not False: assert F ^ F is false if T is not True: assert T ^ T is false assert Nand(T, F) is true assert Nand(F, T) is true assert Nand(F, F) is true assert Nand(T, T) is false assert Nand(T, x) == ~x assert Nand(F, x) is true assert Nor(T, F) is false assert Nor(F, T) is false assert Nor(F, F) is true assert Nor(T, T) is false assert Nor(T, x) is false assert Nor(F, x) == ~x assert Implies(T, F) is false assert Implies(F, T) is true assert Implies(F, F) is true assert Implies(T, T) is true assert Implies(T, x) == x assert Implies(F, x) is true assert Implies(x, T) is true assert Implies(x, F) == ~x if not (T is True and F is False): assert T >> F is false assert F << T is false assert F >> T is true assert T << F is true if F is not False: assert F >> F is true assert F << F is true if T is not True: assert T >> T is true assert T << T is true assert Equivalent(T, F) is false assert Equivalent(F, T) is false assert Equivalent(F, F) is true assert Equivalent(T, T) is true assert Equivalent(T, x) == x assert Equivalent(F, x) == ~x assert Equivalent(x, T) == x assert Equivalent(x, F) == ~x assert ITE(T, T, T) is true assert ITE(T, T, F) is true assert ITE(T, F, T) is false assert ITE(T, F, F) is false assert ITE(F, T, T) is true assert ITE(F, T, F) is false assert ITE(F, F, T) is true assert ITE(F, F, F) is false assert all(i.simplify(1, 2) is i for i in (S.true, S.false)) def test_bool_as_set(): assert ITE(y <= 0, False, y >= 1).as_set() == Interval(1, oo) assert And(x <= 2, x >= -2).as_set() == Interval(-2, 2) assert Or(x >= 2, x <= -2).as_set() == Interval(-oo, -2) + Interval(2, oo) assert Not(x > 2).as_set() == Interval(-oo, 2) # issue 10240 assert Not(And(x > 2, x < 3)).as_set() == \ Union(Interval(-oo, 2), Interval(3, oo)) assert true.as_set() == S.UniversalSet assert false.as_set() == EmptySet() assert x.as_set() == S.UniversalSet assert And(Or(x < 1, x > 3), x < 2).as_set() == Interval.open(-oo, 1) assert And(x < 1, sin(x) < 3).as_set() == (x < 1).as_set() raises(NotImplementedError, lambda: (sin(x) < 1).as_set()) @XFAIL def test_multivariate_bool_as_set(): x, y = symbols('x,y') assert And(x >= 0, y >= 0).as_set() == Interval(0, oo)*Interval(0, oo) assert Or(x >= 0, y >= 0).as_set() == S.Reals*S.Reals - \ Interval(-oo, 0, True, True)*Interval(-oo, 0, True, True) def test_all_or_nothing(): x = symbols('x', extended_real=True) args = x >= -oo, x <= oo v = And(*args) if v.func is And: assert len(v.args) == len(args) - args.count(S.true) else: assert v == True v = Or(*args) if v.func is Or: assert len(v.args) == 2 else: assert v == True def test_canonical_atoms(): assert true.canonical == true assert false.canonical == false def test_negated_atoms(): assert true.negated == false assert false.negated == true def test_issue_8777(): assert And(x > 2, x < oo).as_set() == Interval(2, oo, left_open=True) assert And(x >= 1, x < oo).as_set() == Interval(1, oo) assert (x < oo).as_set() == Interval(-oo, oo) assert (x > -oo).as_set() == Interval(-oo, oo) def test_issue_8975(): assert Or(And(-oo < x, x <= -2), And(2 <= x, x < oo)).as_set() == \ Interval(-oo, -2) + Interval(2, oo) def test_term_to_integer(): assert term_to_integer([1, 0, 1, 0, 0, 1, 0]) == 82 assert term_to_integer('0010101000111001') == 10809 def test_integer_to_term(): assert integer_to_term(777) == [1, 1, 0, 0, 0, 0, 1, 0, 0, 1] assert integer_to_term(123, 3) == [1, 1, 1, 1, 0, 1, 1] assert integer_to_term(456, 16) == [0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 0, 1, 0, 0, 0] def test_truth_table(): assert list(truth_table(And(x, y), [x, y], input=False)) == \ [False, False, False, True] assert list(truth_table(x | y, [x, y], input=False)) == \ [False, True, True, True] assert list(truth_table(x >> y, [x, y], input=False)) == \ [True, True, False, True] assert list(truth_table(And(x, y), [x, y])) == \ [([0, 0], False), ([0, 1], False), ([1, 0], False), ([1, 1], True)] def test_issue_8571(): for t in (S.true, S.false): raises(TypeError, lambda: +t) raises(TypeError, lambda: -t) raises(TypeError, lambda: abs(t)) # use int(bool(t)) to get 0 or 1 raises(TypeError, lambda: int(t)) for o in [S.Zero, S.One, x]: for _ in range(2): raises(TypeError, lambda: o + t) raises(TypeError, lambda: o - t) raises(TypeError, lambda: o % t) raises(TypeError, lambda: o*t) raises(TypeError, lambda: o/t) raises(TypeError, lambda: o**t) o, t = t, o # do again in reversed order def test_expand_relational(): n = symbols('n', negative=True) p, q = symbols('p q', positive=True) r = ((n + q*(-n/q + 1))/(q*(-n/q + 1)) < 0) assert r is not S.false assert r.expand() is S.false assert (q > 0).expand() is S.true def test_issue_12717(): assert S.true.is_Atom == True assert S.false.is_Atom == True def test_as_Boolean(): nz = symbols('nz', nonzero=True) assert all(as_Boolean(i) is S.true for i in (True, S.true, 1, nz)) z = symbols('z', zero=True) assert all(as_Boolean(i) is S.false for i in (False, S.false, 0, z)) assert all(as_Boolean(i) == i for i in (x, x < 0)) for i in (2, S(2), x + 1, []): raises(TypeError, lambda: as_Boolean(i)) def test_binary_symbols(): assert ITE(x < 1, y, z).binary_symbols == {y, z} for f in (Eq, Ne): assert f(x, 1).binary_symbols == set() assert f(x, True).binary_symbols == {x} assert f(x, False).binary_symbols == {x} assert S.true.binary_symbols == set() assert S.false.binary_symbols == set() assert x.binary_symbols == {x} assert And(x, Eq(y, False), Eq(z, 1)).binary_symbols == {x, y} assert Q.prime(x).binary_symbols == set() assert Q.lt(x, 1).binary_symbols == set() assert Q.is_true(x).binary_symbols == {x} assert Q.eq(x, True).binary_symbols == {x} assert Q.prime(x).binary_symbols == set() def test_BooleanFunction_diff(): assert And(x, y).diff(x) == Piecewise((0, Eq(y, False)), (1, True)) def test_issue_14700(): A, B, C, D, E, F, G, H = symbols('A B C D E F G H') q = ((B & D & H & ~F) | (B & H & ~C & ~D) | (B & H & ~C & ~F) | (B & H & ~D & ~G) | (B & H & ~F & ~G) | (C & G & ~B & ~D) | (C & G & ~D & ~H) | (C & G & ~F & ~H) | (D & F & H & ~B) | (D & F & ~G & ~H) | (B & D & F & ~C & ~H) | (D & E & F & ~B & ~C) | (D & F & ~A & ~B & ~C) | (D & F & ~A & ~C & ~H) | (A & B & D & F & ~E & ~H)) soldnf = ((B & D & H & ~F) | (D & F & H & ~B) | (B & H & ~C & ~D) | (B & H & ~D & ~G) | (C & G & ~B & ~D) | (C & G & ~D & ~H) | (C & G & ~F & ~H) | (D & F & ~G & ~H) | (D & E & F & ~C & ~H) | (D & F & ~A & ~C & ~H) | (A & B & D & F & ~E & ~H)) solcnf = ((B | C | D) & (B | D | G) & (C | D | H) & (C | F | H) & (D | G | H) & (F | G | H) & (B | F | ~D | ~H) & (~B | ~D | ~F | ~H) & (D | ~B | ~C | ~G | ~H) & (A | H | ~C | ~D | ~F | ~G) & (H | ~C | ~D | ~E | ~F | ~G) & (B | E | H | ~A | ~D | ~F | ~G)) assert simplify_logic(q, "dnf") == soldnf assert simplify_logic(q, "cnf") == solcnf minterms = [[0, 1, 0, 0], [0, 1, 0, 1], [0, 1, 1, 0], [0, 1, 1, 1], [0, 0, 1, 1], [1, 0, 1, 1]] dontcares = [[1, 0, 0, 0], [1, 0, 0, 1], [1, 1, 0, 0], [1, 1, 0, 1]] assert SOPform([w, x, y, z], minterms) == (x & ~w) | (y & z & ~x) # Should not be more complicated with don't cares assert SOPform([w, x, y, z], minterms, dontcares) == \ (x & ~w) | (y & z & ~x) def test_relational_simplification(): w, x, y, z = symbols('w x y z', real=True) d, e = symbols('d e', real=False) # Test all combinations or sign and order assert Or(x >= y, x < y).simplify() == S.true assert Or(x >= y, y > x).simplify() == S.true assert Or(x >= y, -x > -y).simplify() == S.true assert Or(x >= y, -y < -x).simplify() == S.true assert Or(-x <= -y, x < y).simplify() == S.true assert Or(-x <= -y, -x > -y).simplify() == S.true assert Or(-x <= -y, y > x).simplify() == S.true assert Or(-x <= -y, -y < -x).simplify() == S.true assert Or(y <= x, x < y).simplify() == S.true assert Or(y <= x, y > x).simplify() == S.true assert Or(y <= x, -x > -y).simplify() == S.true assert Or(y <= x, -y < -x).simplify() == S.true assert Or(-y >= -x, x < y).simplify() == S.true assert Or(-y >= -x, y > x).simplify() == S.true assert Or(-y >= -x, -x > -y).simplify() == S.true assert Or(-y >= -x, -y < -x).simplify() == S.true assert Or(x < y, x >= y).simplify() == S.true assert Or(y > x, x >= y).simplify() == S.true assert Or(-x > -y, x >= y).simplify() == S.true assert Or(-y < -x, x >= y).simplify() == S.true assert Or(x < y, -x <= -y).simplify() == S.true assert Or(-x > -y, -x <= -y).simplify() == S.true assert Or(y > x, -x <= -y).simplify() == S.true assert Or(-y < -x, -x <= -y).simplify() == S.true assert Or(x < y, y <= x).simplify() == S.true assert Or(y > x, y <= x).simplify() == S.true assert Or(-x > -y, y <= x).simplify() == S.true assert Or(-y < -x, y <= x).simplify() == S.true assert Or(x < y, -y >= -x).simplify() == S.true assert Or(y > x, -y >= -x).simplify() == S.true assert Or(-x > -y, -y >= -x).simplify() == S.true assert Or(-y < -x, -y >= -x).simplify() == S.true # Some other tests assert Or(x >= y, w < z, x <= y).simplify() == S.true assert And(x >= y, x < y).simplify() == S.false assert Or(x >= y, Eq(y, x)).simplify() == (x >= y) assert And(x >= y, Eq(y, x)).simplify() == Eq(x, y) assert Or(Eq(x, y), x >= y, w < y, z < y).simplify() == \ Or(x >= y, y > Min(w, z)) assert And(Eq(x, y), x >= y, w < y, y >= z, z < y).simplify() == \ And(Eq(x, y), y > Max(w, z)) assert Or(Eq(x, y), x >= 1, 2 < y, y >= 5, z < y).simplify() == \ (Eq(x, y) | (x >= 1) | (y > Min(2, z))) assert And(Eq(x, y), x >= 1, 2 < y, y >= 5, z < y).simplify() == \ (Eq(x, y) & (x >= 1) & (y >= 5) & (y > z)) assert (Eq(x, y) & Eq(d, e) & (x >= y) & (d >= e)).simplify() == \ (Eq(x, y) & Eq(d, e) & (d >= e)) assert And(Eq(x, y), Eq(x, -y)).simplify() == And(Eq(x, 0), Eq(y, 0)) assert Xor(x >= y, x <= y).simplify() == Ne(x, y) @slow def test_relational_simplification_numerically(): def test_simplification_numerically_function(original, simplified): symb = original.free_symbols n = len(symb) valuelist = list(set(list(combinations(list(range(-(n-1), n))*n, n)))) for values in valuelist: sublist = dict(zip(symb, values)) originalvalue = original.subs(sublist) simplifiedvalue = simplified.subs(sublist) assert originalvalue == simplifiedvalue, "Original: {}\nand"\ " simplified: {}\ndo not evaluate to the same value for {}"\ "".format(original, simplified, sublist) w, x, y, z = symbols('w x y z', real=True) d, e = symbols('d e', real=False) expressions = (And(Eq(x, y), x >= y, w < y, y >= z, z < y), And(Eq(x, y), x >= 1, 2 < y, y >= 5, z < y), Or(Eq(x, y), x >= 1, 2 < y, y >= 5, z < y), And(x >= y, Eq(y, x)), Or(And(Eq(x, y), x >= y, w < y, Or(y >= z, z < y)), And(Eq(x, y), x >= 1, 2 < y, y >= -1, z < y)), (Eq(x, y) & Eq(d, e) & (x >= y) & (d >= e)), ) for expression in expressions: test_simplification_numerically_function(expression, expression.simplify()) def test_relational_simplification_patterns_numerically(): from sympy.core import Wild from sympy.logic.boolalg import simplify_patterns_and, \ simplify_patterns_or, simplify_patterns_xor a = Wild('a') b = Wild('b') c = Wild('c') symb = [a, b, c] patternlists = [simplify_patterns_and(), simplify_patterns_or(), simplify_patterns_xor()] for patternlist in patternlists: for pattern in patternlist: original = pattern[0] simplified = pattern[1] valuelist = list(set(list(combinations(list(range(-2, 2))*3, 3)))) for values in valuelist: sublist = dict(zip(symb, values)) originalvalue = original.subs(sublist) simplifiedvalue = simplified.subs(sublist) assert originalvalue == simplifiedvalue, "Original: {}\nand"\ " simplified: {}\ndo not evaluate to the same value for"\ "{}".format(original, simplified, sublist) def test_issue_16803(): n = symbols('n') # No simplification done, but should not raise an exception assert ((n > 3) | (n < 0) | ((n > 0) & (n < 3))).simplify() == \ ((n > 3) | (n < 0) | ((n > 0) & (n < 3))) def test_issue_17530(): r = {x: oo, y: oo} assert Or(x + y > 0, x - y < 0).subs(r) assert not And(x + y < 0, x - y < 0).subs(r) raises(TypeError, lambda: Or(x + y < 0, x - y < 0).subs(r)) raises(TypeError, lambda: And(x + y > 0, x - y < 0).subs(r)) raises(TypeError, lambda: And(x + y > 0, x - y < 0).subs(r)) def test_anf_coeffs(): assert anf_coeffs([1, 0]) == [1, 1] assert anf_coeffs([0, 0, 0, 1]) == [0, 0, 0, 1] assert anf_coeffs([0, 1, 1, 1]) == [0, 1, 1, 1] assert anf_coeffs([1, 1, 1, 0]) == [1, 0, 0, 1] assert anf_coeffs([1, 0, 0, 0]) == [1, 1, 1, 1] assert anf_coeffs([1, 0, 0, 1]) == [1, 1, 1, 0] assert anf_coeffs([1, 1, 0, 1]) == [1, 0, 1, 1] def test_ANFform(): x, y = symbols('x,y') assert ANFform([x], [1, 1]) == True assert ANFform([x], [0, 0]) == False assert ANFform([x], [1, 0]) == Xor(x, True, remove_true=False) assert ANFform([x, y], [1, 1, 1, 0]) == \ Xor(True, And(x, y), remove_true=False) def test_bool_minterm(): x, y = symbols('x,y') assert bool_minterm(3, [x, y]) == And(x, y) assert bool_minterm([1, 0], [x, y]) == And(Not(y), x) def test_bool_maxterm(): x, y = symbols('x,y') assert bool_maxterm(2, [x, y]) == Or(Not(x), y) assert bool_maxterm([0, 1], [x, y]) == Or(Not(y), x) def test_bool_monomial(): x, y = symbols('x,y') assert bool_monomial(1, [x, y]) == y assert bool_monomial([1, 1], [x, y]) == And(x, y) def test_check_pair(): assert _check_pair([0, 1, 0], [0, 1, 1]) == 2 assert _check_pair([0, 1, 0], [1, 1, 1]) == -1 def test_convert_to_varsSOP(): assert _convert_to_varsSOP([0, 1, 0], [x, y, z]) == And(Not(x), y, Not(z)) assert _convert_to_varsSOP([3, 1, 0], [x, y, z]) == And(y, Not(z)) def test_convert_to_varsPOS(): assert _convert_to_varsPOS([0, 1, 0], [x, y, z]) == Or(x, Not(y), z) assert _convert_to_varsPOS([3, 1, 0], [x, y, z]) == Or(Not(y), z) def test_refine(): # relational assert not refine(x < 0, ~(x < 0)) assert refine(x < 0, (x < 0)) assert refine(x < 0, (0 > x)) is S.true assert refine(x < 0, (y < 0)) == (x < 0) assert not refine(x <= 0, ~(x <= 0)) assert refine(x <= 0, (x <= 0)) assert refine(x <= 0, (0 >= x)) is S.true assert refine(x <= 0, (y <= 0)) == (x <= 0) assert not refine(x > 0, ~(x > 0)) assert refine(x > 0, (x > 0)) assert refine(x > 0, (0 < x)) is S.true assert refine(x > 0, (y > 0)) == (x > 0) assert not refine(x >= 0, ~(x >= 0)) assert refine(x >= 0, (x >= 0)) assert refine(x >= 0, (0 <= x)) is S.true assert refine(x >= 0, (y >= 0)) == (x >= 0) assert not refine(Eq(x, 0), ~(Eq(x, 0))) assert refine(Eq(x, 0), (Eq(x, 0))) assert refine(Eq(x, 0), (Eq(0, x))) is S.true assert refine(Eq(x, 0), (Eq(y, 0))) == Eq(x, 0) assert not refine(Ne(x, 0), ~(Ne(x, 0))) assert refine(Ne(x, 0), (Ne(0, x))) is S.true assert refine(Ne(x, 0), (Ne(x, 0))) assert refine(Ne(x, 0), (Ne(y, 0))) == (Ne(x, 0)) # boolean functions assert refine(And(x > 0, y > 0), (x > 0)) == (y > 0) assert refine(And(x > 0, y > 0), (x > 0) & (y > 0)) is S.true # predicates assert refine(Q.positive(x), Q.positive(x)) is S.true assert refine(Q.positive(x), Q.negative(x)) is S.false assert refine(Q.positive(x), Q.real(x)) == Q.positive(x)
841d10a292a4cfc41ff28b3ef0621bed06dd8e866a901fb5e7ab7915e829b4da
"""For more tests on satisfiability, see test_dimacs""" from sympy import symbols, Q from sympy.logic.boolalg import And, Implies, Equivalent, true, false from sympy.logic.inference import literal_symbol, \ pl_true, satisfiable, valid, entails, PropKB from sympy.logic.algorithms.dpll import dpll, dpll_satisfiable, \ find_pure_symbol, find_unit_clause, unit_propagate, \ find_pure_symbol_int_repr, find_unit_clause_int_repr, \ unit_propagate_int_repr from sympy.logic.algorithms.dpll2 import dpll_satisfiable as dpll2_satisfiable from sympy.testing.pytest import raises def test_literal(): A, B = symbols('A,B') assert literal_symbol(True) is True assert literal_symbol(False) is False assert literal_symbol(A) is A assert literal_symbol(~A) is A def test_find_pure_symbol(): A, B, C = symbols('A,B,C') assert find_pure_symbol([A], [A]) == (A, True) assert find_pure_symbol([A, B], [~A | B, ~B | A]) == (None, None) assert find_pure_symbol([A, B, C], [ A | ~B, ~B | ~C, C | A]) == (A, True) assert find_pure_symbol([A, B, C], [~A | B, B | ~C, C | A]) == (B, True) assert find_pure_symbol([A, B, C], [~A | ~B, ~B | ~C, C | A]) == (B, False) assert find_pure_symbol( [A, B, C], [~A | B, ~B | ~C, C | A]) == (None, None) def test_find_pure_symbol_int_repr(): assert find_pure_symbol_int_repr([1], [{1}]) == (1, True) assert find_pure_symbol_int_repr([1, 2], [{-1, 2}, {-2, 1}]) == (None, None) assert find_pure_symbol_int_repr([1, 2, 3], [{1, -2}, {-2, -3}, {3, 1}]) == (1, True) assert find_pure_symbol_int_repr([1, 2, 3], [{-1, 2}, {2, -3}, {3, 1}]) == (2, True) assert find_pure_symbol_int_repr([1, 2, 3], [{-1, -2}, {-2, -3}, {3, 1}]) == (2, False) assert find_pure_symbol_int_repr([1, 2, 3], [{-1, 2}, {-2, -3}, {3, 1}]) == (None, None) def test_unit_clause(): A, B, C = symbols('A,B,C') assert find_unit_clause([A], {}) == (A, True) assert find_unit_clause([A, ~A], {}) == (A, True) # Wrong ?? assert find_unit_clause([A | B], {A: True}) == (B, True) assert find_unit_clause([A | B], {B: True}) == (A, True) assert find_unit_clause( [A | B | C, B | ~C, A | ~B], {A: True}) == (B, False) assert find_unit_clause([A | B | C, B | ~C, A | B], {A: True}) == (B, True) assert find_unit_clause([A | B | C, B | ~C, A ], {}) == (A, True) def test_unit_clause_int_repr(): assert find_unit_clause_int_repr(map(set, [[1]]), {}) == (1, True) assert find_unit_clause_int_repr(map(set, [[1], [-1]]), {}) == (1, True) assert find_unit_clause_int_repr([{1, 2}], {1: True}) == (2, True) assert find_unit_clause_int_repr([{1, 2}], {2: True}) == (1, True) assert find_unit_clause_int_repr(map(set, [[1, 2, 3], [2, -3], [1, -2]]), {1: True}) == (2, False) assert find_unit_clause_int_repr(map(set, [[1, 2, 3], [3, -3], [1, 2]]), {1: True}) == (2, True) A, B, C = symbols('A,B,C') assert find_unit_clause([A | B | C, B | ~C, A ], {}) == (A, True) def test_unit_propagate(): A, B, C = symbols('A,B,C') assert unit_propagate([A | B], A) == [] assert unit_propagate([A | B, ~A | C, ~C | B, A], A) == [C, ~C | B, A] def test_unit_propagate_int_repr(): assert unit_propagate_int_repr([{1, 2}], 1) == [] assert unit_propagate_int_repr(map(set, [[1, 2], [-1, 3], [-3, 2], [1]]), 1) == [{3}, {-3, 2}] def test_dpll(): """This is also tested in test_dimacs""" A, B, C = symbols('A,B,C') assert dpll([A | B], [A, B], {A: True, B: True}) == {A: True, B: True} def test_dpll_satisfiable(): A, B, C = symbols('A,B,C') assert dpll_satisfiable( A & ~A ) is False assert dpll_satisfiable( A & ~B ) == {A: True, B: False} assert dpll_satisfiable( A | B ) in ({A: True}, {B: True}, {A: True, B: True}) assert dpll_satisfiable( (~A | B) & (~B | A) ) in ({A: True, B: True}, {A: False, B: False}) assert dpll_satisfiable( (A | B) & (~B | C) ) in ({A: True, B: False}, {A: True, C: True}, {B: True, C: True}) assert dpll_satisfiable( A & B & C ) == {A: True, B: True, C: True} assert dpll_satisfiable( (A | B) & (A >> B) ) == {B: True} assert dpll_satisfiable( Equivalent(A, B) & A ) == {A: True, B: True} assert dpll_satisfiable( Equivalent(A, B) & ~A ) == {A: False, B: False} def test_dpll2_satisfiable(): A, B, C = symbols('A,B,C') assert dpll2_satisfiable( A & ~A ) is False assert dpll2_satisfiable( A & ~B ) == {A: True, B: False} assert dpll2_satisfiable( A | B ) in ({A: True}, {B: True}, {A: True, B: True}) assert dpll2_satisfiable( (~A | B) & (~B | A) ) in ({A: True, B: True}, {A: False, B: False}) assert dpll2_satisfiable( (A | B) & (~B | C) ) in ({A: True, B: False, C: True}, {A: True, B: True, C: True}) assert dpll2_satisfiable( A & B & C ) == {A: True, B: True, C: True} assert dpll2_satisfiable( (A | B) & (A >> B) ) in ({B: True, A: False}, {B: True, A: True}) assert dpll2_satisfiable( Equivalent(A, B) & A ) == {A: True, B: True} assert dpll2_satisfiable( Equivalent(A, B) & ~A ) == {A: False, B: False} def test_minisat22_satisfiable(): A, B, C = symbols('A,B,C') minisat22_satisfiable = lambda expr: satisfiable(expr, algorithm="minisat22") assert minisat22_satisfiable( A & ~A ) is False assert minisat22_satisfiable( A & ~B ) == {A: True, B: False} assert minisat22_satisfiable( A | B ) in ({A: True}, {B: False}, {A: False, B: True}, {A: True, B: True}, {A: True, B: False}) assert minisat22_satisfiable( (~A | B) & (~B | A) ) in ({A: True, B: True}, {A: False, B: False}) assert minisat22_satisfiable( (A | B) & (~B | C) ) in ({A: True, B: False, C: True}, {A: True, B: True, C: True}, {A: False, B: True, C: True}, {A: True, B: False, C: False}) assert minisat22_satisfiable( A & B & C ) == {A: True, B: True, C: True} assert minisat22_satisfiable( (A | B) & (A >> B) ) in ({B: True, A: False}, {B: True, A: True}) assert minisat22_satisfiable( Equivalent(A, B) & A ) == {A: True, B: True} assert minisat22_satisfiable( Equivalent(A, B) & ~A ) == {A: False, B: False} def test_minisat22_minimal_satisfiable(): A, B, C = symbols('A,B,C') minisat22_satisfiable = lambda expr, minimal=True: satisfiable(expr, algorithm="minisat22", minimal=True) assert minisat22_satisfiable( A & ~A ) is False assert minisat22_satisfiable( A & ~B ) == {A: True, B: False} assert minisat22_satisfiable( A | B ) in ({A: True}, {B: False}, {A: False, B: True}, {A: True, B: True}, {A: True, B: False}) assert minisat22_satisfiable( (~A | B) & (~B | A) ) in ({A: True, B: True}, {A: False, B: False}) assert minisat22_satisfiable( (A | B) & (~B | C) ) in ({A: True, B: False, C: True}, {A: True, B: True, C: True}, {A: False, B: True, C: True}, {A: True, B: False, C: False}) assert minisat22_satisfiable( A & B & C ) == {A: True, B: True, C: True} assert minisat22_satisfiable( (A | B) & (A >> B) ) in ({B: True, A: False}, {B: True, A: True}) assert minisat22_satisfiable( Equivalent(A, B) & A ) == {A: True, B: True} assert minisat22_satisfiable( Equivalent(A, B) & ~A ) == {A: False, B: False} g = satisfiable((A | B | C),algorithm="minisat22",minimal=True,all_models=True) sol = next(g) first_solution = {key for key, value in sol.items() if value} sol=next(g) second_solution = {key for key, value in sol.items() if value} sol=next(g) third_solution = {key for key, value in sol.items() if value} assert not first_solution <= second_solution assert not second_solution <= third_solution assert not first_solution <= third_solution def test_satisfiable(): A, B, C = symbols('A,B,C') assert satisfiable(A & (A >> B) & ~B) is False def test_valid(): A, B, C = symbols('A,B,C') assert valid(A >> (B >> A)) is True assert valid((A >> (B >> C)) >> ((A >> B) >> (A >> C))) is True assert valid((~B >> ~A) >> (A >> B)) is True assert valid(A | B | C) is False assert valid(A >> B) is False def test_pl_true(): A, B, C = symbols('A,B,C') assert pl_true(True) is True assert pl_true( A & B, {A: True, B: True}) is True assert pl_true( A | B, {A: True}) is True assert pl_true( A | B, {B: True}) is True assert pl_true( A | B, {A: None, B: True}) is True assert pl_true( A >> B, {A: False}) is True assert pl_true( A | B | ~C, {A: False, B: True, C: True}) is True assert pl_true(Equivalent(A, B), {A: False, B: False}) is True # test for false assert pl_true(False) is False assert pl_true( A & B, {A: False, B: False}) is False assert pl_true( A & B, {A: False}) is False assert pl_true( A & B, {B: False}) is False assert pl_true( A | B, {A: False, B: False}) is False #test for None assert pl_true(B, {B: None}) is None assert pl_true( A & B, {A: True, B: None}) is None assert pl_true( A >> B, {A: True, B: None}) is None assert pl_true(Equivalent(A, B), {A: None}) is None assert pl_true(Equivalent(A, B), {A: True, B: None}) is None # Test for deep assert pl_true(A | B, {A: False}, deep=True) is None assert pl_true(~A & ~B, {A: False}, deep=True) is None assert pl_true(A | B, {A: False, B: False}, deep=True) is False assert pl_true(A & B & (~A | ~B), {A: True}, deep=True) is False assert pl_true((C >> A) >> (B >> A), {C: True}, deep=True) is True def test_pl_true_wrong_input(): from sympy import pi raises(ValueError, lambda: pl_true('John Cleese')) raises(ValueError, lambda: pl_true(42 + pi + pi ** 2)) raises(ValueError, lambda: pl_true(42)) def test_entails(): A, B, C = symbols('A, B, C') assert entails(A, [A >> B, ~B]) is False assert entails(B, [Equivalent(A, B), A]) is True assert entails((A >> B) >> (~A >> ~B)) is False assert entails((A >> B) >> (~B >> ~A)) is True def test_PropKB(): A, B, C = symbols('A,B,C') kb = PropKB() assert kb.ask(A >> B) is False assert kb.ask(A >> (B >> A)) is True kb.tell(A >> B) kb.tell(B >> C) assert kb.ask(A) is False assert kb.ask(B) is False assert kb.ask(C) is False assert kb.ask(~A) is False assert kb.ask(~B) is False assert kb.ask(~C) is False assert kb.ask(A >> C) is True kb.tell(A) assert kb.ask(A) is True assert kb.ask(B) is True assert kb.ask(C) is True assert kb.ask(~C) is False kb.retract(A) assert kb.ask(C) is False def test_propKB_tolerant(): """"tolerant to bad input""" kb = PropKB() A, B, C = symbols('A,B,C') assert kb.ask(B) is False def test_satisfiable_non_symbols(): x, y = symbols('x y') assumptions = Q.zero(x*y) facts = Implies(Q.zero(x*y), Q.zero(x) | Q.zero(y)) query = ~Q.zero(x) & ~Q.zero(y) refutations = [ {Q.zero(x): True, Q.zero(x*y): True}, {Q.zero(y): True, Q.zero(x*y): True}, {Q.zero(x): True, Q.zero(y): True, Q.zero(x*y): True}, {Q.zero(x): True, Q.zero(y): False, Q.zero(x*y): True}, {Q.zero(x): False, Q.zero(y): True, Q.zero(x*y): True}] assert not satisfiable(And(assumptions, facts, query), algorithm='dpll') assert satisfiable(And(assumptions, facts, ~query), algorithm='dpll') in refutations assert not satisfiable(And(assumptions, facts, query), algorithm='dpll2') assert satisfiable(And(assumptions, facts, ~query), algorithm='dpll2') in refutations def test_satisfiable_bool(): from sympy.core.singleton import S assert satisfiable(true) == {true: true} assert satisfiable(S.true) == {true: true} assert satisfiable(false) is False assert satisfiable(S.false) is False def test_satisfiable_all_models(): from sympy.abc import A, B assert next(satisfiable(False, all_models=True)) is False assert list(satisfiable((A >> ~A) & A , all_models=True)) == [False] assert list(satisfiable(True, all_models=True)) == [{true: true}] models = [{A: True, B: False}, {A: False, B: True}] result = satisfiable(A ^ B, all_models=True) models.remove(next(result)) models.remove(next(result)) raises(StopIteration, lambda: next(result)) assert not models assert list(satisfiable(Equivalent(A, B), all_models=True)) == \ [{A: False, B: False}, {A: True, B: True}] models = [{A: False, B: False}, {A: False, B: True}, {A: True, B: True}] for model in satisfiable(A >> B, all_models=True): models.remove(model) assert not models # This is a santiy test to check that only the required number # of solutions are generated. The expr below has 2**100 - 1 models # which would time out the test if all are generated at once. from sympy import numbered_symbols from sympy.logic.boolalg import Or sym = numbered_symbols() X = [next(sym) for i in range(100)] result = satisfiable(Or(*X), all_models=True) for i in range(10): assert next(result)
6be8f363083e434f94e0be56811e3089dc2a88f49e2a28d09b4d7bd29c4ee1e1
from sympy.assumptions import Q from sympy.core.expr import Expr from sympy.core.add import Add from sympy.core.function import Function from sympy.core.numbers import I, Integer, oo, pi, Rational from sympy.core.singleton import S from sympy.core.symbol import Symbol, symbols from sympy.functions.elementary.complexes import Abs from sympy.functions.elementary.exponential import exp from sympy.functions.elementary.miscellaneous import sqrt from sympy.functions.elementary.trigonometric import cos, sin from sympy.matrices.common import (ShapeError, NonSquareMatrixError, _MinimalMatrix, _CastableMatrix, MatrixShaping, MatrixProperties, MatrixOperations, MatrixArithmetic, MatrixSpecial) from sympy.matrices.matrices import MatrixCalculus from sympy.matrices import (Matrix, diag, eye, matrix_multiply_elementwise, ones, zeros, SparseMatrix, banded, MutableDenseMatrix, MutableSparseMatrix, ImmutableDenseMatrix, ImmutableSparseMatrix) from sympy.polys.polytools import Poly from sympy.utilities.iterables import flatten from sympy.testing.pytest import raises, XFAIL, warns_deprecated_sympy from sympy import Array from sympy.abc import x, y, z # classes to test the basic matrix classes class ShapingOnlyMatrix(_MinimalMatrix, _CastableMatrix, MatrixShaping): pass def eye_Shaping(n): return ShapingOnlyMatrix(n, n, lambda i, j: int(i == j)) def zeros_Shaping(n): return ShapingOnlyMatrix(n, n, lambda i, j: 0) class PropertiesOnlyMatrix(_MinimalMatrix, _CastableMatrix, MatrixProperties): pass def eye_Properties(n): return PropertiesOnlyMatrix(n, n, lambda i, j: int(i == j)) def zeros_Properties(n): return PropertiesOnlyMatrix(n, n, lambda i, j: 0) class OperationsOnlyMatrix(_MinimalMatrix, _CastableMatrix, MatrixOperations): pass def eye_Operations(n): return OperationsOnlyMatrix(n, n, lambda i, j: int(i == j)) def zeros_Operations(n): return OperationsOnlyMatrix(n, n, lambda i, j: 0) class ArithmeticOnlyMatrix(_MinimalMatrix, _CastableMatrix, MatrixArithmetic): pass def eye_Arithmetic(n): return ArithmeticOnlyMatrix(n, n, lambda i, j: int(i == j)) def zeros_Arithmetic(n): return ArithmeticOnlyMatrix(n, n, lambda i, j: 0) class SpecialOnlyMatrix(_MinimalMatrix, _CastableMatrix, MatrixSpecial): pass class CalculusOnlyMatrix(_MinimalMatrix, _CastableMatrix, MatrixCalculus): pass def test__MinimalMatrix(): x = _MinimalMatrix(2, 3, [1, 2, 3, 4, 5, 6]) assert x.rows == 2 assert x.cols == 3 assert x[2] == 3 assert x[1, 1] == 5 assert list(x) == [1, 2, 3, 4, 5, 6] assert list(x[1, :]) == [4, 5, 6] assert list(x[:, 1]) == [2, 5] assert list(x[:, :]) == list(x) assert x[:, :] == x assert _MinimalMatrix(x) == x assert _MinimalMatrix([[1, 2, 3], [4, 5, 6]]) == x assert _MinimalMatrix(([1, 2, 3], [4, 5, 6])) == x assert _MinimalMatrix([(1, 2, 3), (4, 5, 6)]) == x assert _MinimalMatrix(((1, 2, 3), (4, 5, 6))) == x assert not (_MinimalMatrix([[1, 2], [3, 4], [5, 6]]) == x) # ShapingOnlyMatrix tests def test_vec(): m = ShapingOnlyMatrix(2, 2, [1, 3, 2, 4]) m_vec = m.vec() assert m_vec.cols == 1 for i in range(4): assert m_vec[i] == i + 1 def test_todok(): a, b, c, d = symbols('a:d') m1 = MutableDenseMatrix([[a, b], [c, d]]) m2 = ImmutableDenseMatrix([[a, b], [c, d]]) m3 = MutableSparseMatrix([[a, b], [c, d]]) m4 = ImmutableSparseMatrix([[a, b], [c, d]]) assert m1.todok() == m2.todok() == m3.todok() == m4.todok() == \ {(0, 0): a, (0, 1): b, (1, 0): c, (1, 1): d} def test_tolist(): lst = [[S.One, S.Half, x*y, S.Zero], [x, y, z, x**2], [y, -S.One, z*x, 3]] flat_lst = [S.One, S.Half, x*y, S.Zero, x, y, z, x**2, y, -S.One, z*x, 3] m = ShapingOnlyMatrix(3, 4, flat_lst) assert m.tolist() == lst def test_todod(): m = ShapingOnlyMatrix(3, 2, [[S.One, 0], [0, S.Half], [x, 0]]) dict = {0: {0: S.One}, 1: {1: S.Half}, 2: {0: x}} assert m.todod() == dict def test_row_col_del(): e = ShapingOnlyMatrix(3, 3, [1, 2, 3, 4, 5, 6, 7, 8, 9]) raises(IndexError, lambda: e.row_del(5)) raises(IndexError, lambda: e.row_del(-5)) raises(IndexError, lambda: e.col_del(5)) raises(IndexError, lambda: e.col_del(-5)) assert e.row_del(2) == e.row_del(-1) == Matrix([[1, 2, 3], [4, 5, 6]]) assert e.col_del(2) == e.col_del(-1) == Matrix([[1, 2], [4, 5], [7, 8]]) assert e.row_del(1) == e.row_del(-2) == Matrix([[1, 2, 3], [7, 8, 9]]) assert e.col_del(1) == e.col_del(-2) == Matrix([[1, 3], [4, 6], [7, 9]]) def test_get_diag_blocks1(): a = Matrix([[1, 2], [2, 3]]) b = Matrix([[3, x], [y, 3]]) c = Matrix([[3, x, 3], [y, 3, z], [x, y, z]]) assert a.get_diag_blocks() == [a] assert b.get_diag_blocks() == [b] assert c.get_diag_blocks() == [c] def test_get_diag_blocks2(): a = Matrix([[1, 2], [2, 3]]) b = Matrix([[3, x], [y, 3]]) c = Matrix([[3, x, 3], [y, 3, z], [x, y, z]]) A, B, C, D = diag(a, b, b), diag(a, b, c), diag(a, c, b), diag(c, c, b) A = ShapingOnlyMatrix(A.rows, A.cols, A) B = ShapingOnlyMatrix(B.rows, B.cols, B) C = ShapingOnlyMatrix(C.rows, C.cols, C) D = ShapingOnlyMatrix(D.rows, D.cols, D) assert A.get_diag_blocks() == [a, b, b] assert B.get_diag_blocks() == [a, b, c] assert C.get_diag_blocks() == [a, c, b] assert D.get_diag_blocks() == [c, c, b] def test_shape(): m = ShapingOnlyMatrix(1, 2, [0, 0]) m.shape == (1, 2) def test_reshape(): m0 = eye_Shaping(3) assert m0.reshape(1, 9) == Matrix(1, 9, (1, 0, 0, 0, 1, 0, 0, 0, 1)) m1 = ShapingOnlyMatrix(3, 4, lambda i, j: i + j) assert m1.reshape( 4, 3) == Matrix(((0, 1, 2), (3, 1, 2), (3, 4, 2), (3, 4, 5))) assert m1.reshape(2, 6) == Matrix(((0, 1, 2, 3, 1, 2), (3, 4, 2, 3, 4, 5))) def test_row_col(): m = ShapingOnlyMatrix(3, 3, [1, 2, 3, 4, 5, 6, 7, 8, 9]) assert m.row(0) == Matrix(1, 3, [1, 2, 3]) assert m.col(0) == Matrix(3, 1, [1, 4, 7]) def test_row_join(): assert eye_Shaping(3).row_join(Matrix([7, 7, 7])) == \ Matrix([[1, 0, 0, 7], [0, 1, 0, 7], [0, 0, 1, 7]]) def test_col_join(): assert eye_Shaping(3).col_join(Matrix([[7, 7, 7]])) == \ Matrix([[1, 0, 0], [0, 1, 0], [0, 0, 1], [7, 7, 7]]) def test_row_insert(): r4 = Matrix([[4, 4, 4]]) for i in range(-4, 5): l = [1, 0, 0] l.insert(i, 4) assert flatten(eye_Shaping(3).row_insert(i, r4).col(0).tolist()) == l def test_col_insert(): c4 = Matrix([4, 4, 4]) for i in range(-4, 5): l = [0, 0, 0] l.insert(i, 4) assert flatten(zeros_Shaping(3).col_insert(i, c4).row(0).tolist()) == l # issue 13643 assert eye_Shaping(6).col_insert(3, Matrix([[2, 2], [2, 2], [2, 2], [2, 2], [2, 2], [2, 2]])) == \ Matrix([[1, 0, 0, 2, 2, 0, 0, 0], [0, 1, 0, 2, 2, 0, 0, 0], [0, 0, 1, 2, 2, 0, 0, 0], [0, 0, 0, 2, 2, 1, 0, 0], [0, 0, 0, 2, 2, 0, 1, 0], [0, 0, 0, 2, 2, 0, 0, 1]]) def test_extract(): m = ShapingOnlyMatrix(4, 3, lambda i, j: i*3 + j) assert m.extract([0, 1, 3], [0, 1]) == Matrix(3, 2, [0, 1, 3, 4, 9, 10]) assert m.extract([0, 3], [0, 0, 2]) == Matrix(2, 3, [0, 0, 2, 9, 9, 11]) assert m.extract(range(4), range(3)) == m raises(IndexError, lambda: m.extract([4], [0])) raises(IndexError, lambda: m.extract([0], [3])) def test_hstack(): m = ShapingOnlyMatrix(4, 3, lambda i, j: i*3 + j) m2 = ShapingOnlyMatrix(3, 4, lambda i, j: i*3 + j) assert m == m.hstack(m) assert m.hstack(m, m, m) == ShapingOnlyMatrix.hstack(m, m, m) == Matrix([ [0, 1, 2, 0, 1, 2, 0, 1, 2], [3, 4, 5, 3, 4, 5, 3, 4, 5], [6, 7, 8, 6, 7, 8, 6, 7, 8], [9, 10, 11, 9, 10, 11, 9, 10, 11]]) raises(ShapeError, lambda: m.hstack(m, m2)) assert Matrix.hstack() == Matrix() # test regression #12938 M1 = Matrix.zeros(0, 0) M2 = Matrix.zeros(0, 1) M3 = Matrix.zeros(0, 2) M4 = Matrix.zeros(0, 3) m = ShapingOnlyMatrix.hstack(M1, M2, M3, M4) assert m.rows == 0 and m.cols == 6 def test_vstack(): m = ShapingOnlyMatrix(4, 3, lambda i, j: i*3 + j) m2 = ShapingOnlyMatrix(3, 4, lambda i, j: i*3 + j) assert m == m.vstack(m) assert m.vstack(m, m, m) == ShapingOnlyMatrix.vstack(m, m, m) == Matrix([ [0, 1, 2], [3, 4, 5], [6, 7, 8], [9, 10, 11], [0, 1, 2], [3, 4, 5], [6, 7, 8], [9, 10, 11], [0, 1, 2], [3, 4, 5], [6, 7, 8], [9, 10, 11]]) raises(ShapeError, lambda: m.vstack(m, m2)) assert Matrix.vstack() == Matrix() # PropertiesOnlyMatrix tests def test_atoms(): m = PropertiesOnlyMatrix(2, 2, [1, 2, x, 1 - 1/x]) assert m.atoms() == {S.One, S(2), S.NegativeOne, x} assert m.atoms(Symbol) == {x} def test_free_symbols(): assert PropertiesOnlyMatrix([[x], [0]]).free_symbols == {x} def test_has(): A = PropertiesOnlyMatrix(((x, y), (2, 3))) assert A.has(x) assert not A.has(z) assert A.has(Symbol) A = PropertiesOnlyMatrix(((2, y), (2, 3))) assert not A.has(x) def test_is_anti_symmetric(): x = symbols('x') assert PropertiesOnlyMatrix(2, 1, [1, 2]).is_anti_symmetric() is False m = PropertiesOnlyMatrix(3, 3, [0, x**2 + 2*x + 1, y, -(x + 1)**2, 0, x*y, -y, -x*y, 0]) assert m.is_anti_symmetric() is True assert m.is_anti_symmetric(simplify=False) is False assert m.is_anti_symmetric(simplify=lambda x: x) is False m = PropertiesOnlyMatrix(3, 3, [x.expand() for x in m]) assert m.is_anti_symmetric(simplify=False) is True m = PropertiesOnlyMatrix(3, 3, [x.expand() for x in [S.One] + list(m)[1:]]) assert m.is_anti_symmetric() is False def test_diagonal_symmetrical(): m = PropertiesOnlyMatrix(2, 2, [0, 1, 1, 0]) assert not m.is_diagonal() assert m.is_symmetric() assert m.is_symmetric(simplify=False) m = PropertiesOnlyMatrix(2, 2, [1, 0, 0, 1]) assert m.is_diagonal() m = PropertiesOnlyMatrix(3, 3, diag(1, 2, 3)) assert m.is_diagonal() assert m.is_symmetric() m = PropertiesOnlyMatrix(3, 3, [1, 0, 0, 0, 2, 0, 0, 0, 3]) assert m == diag(1, 2, 3) m = PropertiesOnlyMatrix(2, 3, zeros(2, 3)) assert not m.is_symmetric() assert m.is_diagonal() m = PropertiesOnlyMatrix(((5, 0), (0, 6), (0, 0))) assert m.is_diagonal() m = PropertiesOnlyMatrix(((5, 0, 0), (0, 6, 0))) assert m.is_diagonal() m = Matrix(3, 3, [1, x**2 + 2*x + 1, y, (x + 1)**2, 2, 0, y, 0, 3]) assert m.is_symmetric() assert not m.is_symmetric(simplify=False) assert m.expand().is_symmetric(simplify=False) def test_is_hermitian(): a = PropertiesOnlyMatrix([[1, I], [-I, 1]]) assert a.is_hermitian a = PropertiesOnlyMatrix([[2*I, I], [-I, 1]]) assert a.is_hermitian is False a = PropertiesOnlyMatrix([[x, I], [-I, 1]]) assert a.is_hermitian is None a = PropertiesOnlyMatrix([[x, 1], [-I, 1]]) assert a.is_hermitian is False def test_is_Identity(): assert eye_Properties(3).is_Identity assert not PropertiesOnlyMatrix(zeros(3)).is_Identity assert not PropertiesOnlyMatrix(ones(3)).is_Identity # issue 6242 assert not PropertiesOnlyMatrix([[1, 0, 0]]).is_Identity def test_is_symbolic(): a = PropertiesOnlyMatrix([[x, x], [x, x]]) assert a.is_symbolic() is True a = PropertiesOnlyMatrix([[1, 2, 3, 4], [5, 6, 7, 8]]) assert a.is_symbolic() is False a = PropertiesOnlyMatrix([[1, 2, 3, 4], [5, 6, x, 8]]) assert a.is_symbolic() is True a = PropertiesOnlyMatrix([[1, x, 3]]) assert a.is_symbolic() is True a = PropertiesOnlyMatrix([[1, 2, 3]]) assert a.is_symbolic() is False a = PropertiesOnlyMatrix([[1], [x], [3]]) assert a.is_symbolic() is True a = PropertiesOnlyMatrix([[1], [2], [3]]) assert a.is_symbolic() is False def test_is_upper(): a = PropertiesOnlyMatrix([[1, 2, 3]]) assert a.is_upper is True a = PropertiesOnlyMatrix([[1], [2], [3]]) assert a.is_upper is False def test_is_lower(): a = PropertiesOnlyMatrix([[1, 2, 3]]) assert a.is_lower is False a = PropertiesOnlyMatrix([[1], [2], [3]]) assert a.is_lower is True def test_is_square(): m = PropertiesOnlyMatrix([[1], [1]]) m2 = PropertiesOnlyMatrix([[2, 2], [2, 2]]) assert not m.is_square assert m2.is_square def test_is_symmetric(): m = PropertiesOnlyMatrix(2, 2, [0, 1, 1, 0]) assert m.is_symmetric() m = PropertiesOnlyMatrix(2, 2, [0, 1, 0, 1]) assert not m.is_symmetric() def test_is_hessenberg(): A = PropertiesOnlyMatrix([[3, 4, 1], [2, 4, 5], [0, 1, 2]]) assert A.is_upper_hessenberg A = PropertiesOnlyMatrix(3, 3, [3, 2, 0, 4, 4, 1, 1, 5, 2]) assert A.is_lower_hessenberg A = PropertiesOnlyMatrix(3, 3, [3, 2, -1, 4, 4, 1, 1, 5, 2]) assert A.is_lower_hessenberg is False assert A.is_upper_hessenberg is False A = PropertiesOnlyMatrix([[3, 4, 1], [2, 4, 5], [3, 1, 2]]) assert not A.is_upper_hessenberg def test_is_zero(): assert PropertiesOnlyMatrix(0, 0, []).is_zero_matrix assert PropertiesOnlyMatrix([[0, 0], [0, 0]]).is_zero_matrix assert PropertiesOnlyMatrix(zeros(3, 4)).is_zero_matrix assert not PropertiesOnlyMatrix(eye(3)).is_zero_matrix assert PropertiesOnlyMatrix([[x, 0], [0, 0]]).is_zero_matrix == None assert PropertiesOnlyMatrix([[x, 1], [0, 0]]).is_zero_matrix == False a = Symbol('a', nonzero=True) assert PropertiesOnlyMatrix([[a, 0], [0, 0]]).is_zero_matrix == False def test_values(): assert set(PropertiesOnlyMatrix(2, 2, [0, 1, 2, 3] ).values()) == {1, 2, 3} x = Symbol('x', real=True) assert set(PropertiesOnlyMatrix(2, 2, [x, 0, 0, 1] ).values()) == {x, 1} # OperationsOnlyMatrix tests def test_applyfunc(): m0 = OperationsOnlyMatrix(eye(3)) assert m0.applyfunc(lambda x: 2*x) == eye(3)*2 assert m0.applyfunc(lambda x: 0) == zeros(3) assert m0.applyfunc(lambda x: 1) == ones(3) def test_adjoint(): dat = [[0, I], [1, 0]] ans = OperationsOnlyMatrix([[0, 1], [-I, 0]]) assert ans.adjoint() == Matrix(dat) def test_as_real_imag(): m1 = OperationsOnlyMatrix(2, 2, [1, 2, 3, 4]) m3 = OperationsOnlyMatrix(2, 2, [1 + S.ImaginaryUnit, 2 + 2*S.ImaginaryUnit, 3 + 3*S.ImaginaryUnit, 4 + 4*S.ImaginaryUnit]) a, b = m3.as_real_imag() assert a == m1 assert b == m1 def test_conjugate(): M = OperationsOnlyMatrix([[0, I, 5], [1, 2, 0]]) assert M.T == Matrix([[0, 1], [I, 2], [5, 0]]) assert M.C == Matrix([[0, -I, 5], [1, 2, 0]]) assert M.C == M.conjugate() assert M.H == M.T.C assert M.H == Matrix([[ 0, 1], [-I, 2], [ 5, 0]]) def test_doit(): a = OperationsOnlyMatrix([[Add(x, x, evaluate=False)]]) assert a[0] != 2*x assert a.doit() == Matrix([[2*x]]) def test_evalf(): a = OperationsOnlyMatrix(2, 1, [sqrt(5), 6]) assert all(a.evalf()[i] == a[i].evalf() for i in range(2)) assert all(a.evalf(2)[i] == a[i].evalf(2) for i in range(2)) assert all(a.n(2)[i] == a[i].n(2) for i in range(2)) def test_expand(): m0 = OperationsOnlyMatrix([[x*(x + y), 2], [((x + y)*y)*x, x*(y + x*(x + y))]]) # Test if expand() returns a matrix m1 = m0.expand() assert m1 == Matrix( [[x*y + x**2, 2], [x*y**2 + y*x**2, x*y + y*x**2 + x**3]]) a = Symbol('a', real=True) assert OperationsOnlyMatrix(1, 1, [exp(I*a)]).expand(complex=True) == \ Matrix([cos(a) + I*sin(a)]) def test_refine(): m0 = OperationsOnlyMatrix([[Abs(x)**2, sqrt(x**2)], [sqrt(x**2)*Abs(y)**2, sqrt(y**2)*Abs(x)**2]]) m1 = m0.refine(Q.real(x) & Q.real(y)) assert m1 == Matrix([[x**2, Abs(x)], [y**2*Abs(x), x**2*Abs(y)]]) m1 = m0.refine(Q.positive(x) & Q.positive(y)) assert m1 == Matrix([[x**2, x], [x*y**2, x**2*y]]) m1 = m0.refine(Q.negative(x) & Q.negative(y)) assert m1 == Matrix([[x**2, -x], [-x*y**2, -x**2*y]]) def test_replace(): F, G = symbols('F, G', cls=Function) K = OperationsOnlyMatrix(2, 2, lambda i, j: G(i+j)) M = OperationsOnlyMatrix(2, 2, lambda i, j: F(i+j)) N = M.replace(F, G) assert N == K def test_replace_map(): F, G = symbols('F, G', cls=Function) K = OperationsOnlyMatrix(2, 2, [(G(0), {F(0): G(0)}), (G(1), {F(1): G(1)}), (G(1), {F(1) \ : G(1)}), (G(2), {F(2): G(2)})]) M = OperationsOnlyMatrix(2, 2, lambda i, j: F(i+j)) N = M.replace(F, G, True) assert N == K def test_rot90(): A = Matrix([[1, 2], [3, 4]]) assert A == A.rot90(0) == A.rot90(4) assert A.rot90(2) == A.rot90(-2) == A.rot90(6) == Matrix(((4, 3), (2, 1))) assert A.rot90(3) == A.rot90(-1) == A.rot90(7) == Matrix(((2, 4), (1, 3))) assert A.rot90() == A.rot90(-7) == A.rot90(-3) == Matrix(((3, 1), (4, 2))) def test_simplify(): n = Symbol('n') f = Function('f') M = OperationsOnlyMatrix([[ 1/x + 1/y, (x + x*y) / x ], [ (f(x) + y*f(x))/f(x), 2 * (1/n - cos(n * pi)/n) / pi ]]) assert M.simplify() == Matrix([[ (x + y)/(x * y), 1 + y ], [ 1 + y, 2*((1 - 1*cos(pi*n))/(pi*n)) ]]) eq = (1 + x)**2 M = OperationsOnlyMatrix([[eq]]) assert M.simplify() == Matrix([[eq]]) assert M.simplify(ratio=oo) == Matrix([[eq.simplify(ratio=oo)]]) def test_subs(): assert OperationsOnlyMatrix([[1, x], [x, 4]]).subs(x, 5) == Matrix([[1, 5], [5, 4]]) assert OperationsOnlyMatrix([[x, 2], [x + y, 4]]).subs([[x, -1], [y, -2]]) == \ Matrix([[-1, 2], [-3, 4]]) assert OperationsOnlyMatrix([[x, 2], [x + y, 4]]).subs([(x, -1), (y, -2)]) == \ Matrix([[-1, 2], [-3, 4]]) assert OperationsOnlyMatrix([[x, 2], [x + y, 4]]).subs({x: -1, y: -2}) == \ Matrix([[-1, 2], [-3, 4]]) assert OperationsOnlyMatrix([[x*y]]).subs({x: y - 1, y: x - 1}, simultaneous=True) == \ Matrix([[(x - 1)*(y - 1)]]) def test_trace(): M = OperationsOnlyMatrix([[1, 0, 0], [0, 5, 0], [0, 0, 8]]) assert M.trace() == 14 def test_xreplace(): assert OperationsOnlyMatrix([[1, x], [x, 4]]).xreplace({x: 5}) == \ Matrix([[1, 5], [5, 4]]) assert OperationsOnlyMatrix([[x, 2], [x + y, 4]]).xreplace({x: -1, y: -2}) == \ Matrix([[-1, 2], [-3, 4]]) def test_permute(): a = OperationsOnlyMatrix(3, 4, [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12]) raises(IndexError, lambda: a.permute([[0, 5]])) raises(ValueError, lambda: a.permute(Symbol('x'))) b = a.permute_rows([[0, 2], [0, 1]]) assert a.permute([[0, 2], [0, 1]]) == b == Matrix([ [5, 6, 7, 8], [9, 10, 11, 12], [1, 2, 3, 4]]) b = a.permute_cols([[0, 2], [0, 1]]) assert a.permute([[0, 2], [0, 1]], orientation='cols') == b ==\ Matrix([ [ 2, 3, 1, 4], [ 6, 7, 5, 8], [10, 11, 9, 12]]) b = a.permute_cols([[0, 2], [0, 1]], direction='backward') assert a.permute([[0, 2], [0, 1]], orientation='cols', direction='backward') == b ==\ Matrix([ [ 3, 1, 2, 4], [ 7, 5, 6, 8], [11, 9, 10, 12]]) assert a.permute([1, 2, 0, 3]) == Matrix([ [5, 6, 7, 8], [9, 10, 11, 12], [1, 2, 3, 4]]) from sympy.combinatorics import Permutation assert a.permute(Permutation([1, 2, 0, 3])) == Matrix([ [5, 6, 7, 8], [9, 10, 11, 12], [1, 2, 3, 4]]) def test_upper_triangular(): A = OperationsOnlyMatrix([ [1, 1, 1, 1], [1, 1, 1, 1], [1, 1, 1, 1], [1, 1, 1, 1] ]) R = A.upper_triangular(2) assert R == OperationsOnlyMatrix([ [0, 0, 1, 1], [0, 0, 0, 1], [0, 0, 0, 0], [0, 0, 0, 0] ]) R = A.upper_triangular(-2) assert R == OperationsOnlyMatrix([ [1, 1, 1, 1], [1, 1, 1, 1], [1, 1, 1, 1], [0, 1, 1, 1] ]) R = A.upper_triangular() assert R == OperationsOnlyMatrix([ [1, 1, 1, 1], [0, 1, 1, 1], [0, 0, 1, 1], [0, 0, 0, 1] ]) def test_lower_triangular(): A = OperationsOnlyMatrix([ [1, 1, 1, 1], [1, 1, 1, 1], [1, 1, 1, 1], [1, 1, 1, 1] ]) L = A.lower_triangular() assert L == ArithmeticOnlyMatrix([ [1, 0, 0, 0], [1, 1, 0, 0], [1, 1, 1, 0], [1, 1, 1, 1]]) L = A.lower_triangular(2) assert L == ArithmeticOnlyMatrix([ [1, 1, 1, 0], [1, 1, 1, 1], [1, 1, 1, 1], [1, 1, 1, 1] ]) L = A.lower_triangular(-2) assert L == ArithmeticOnlyMatrix([ [0, 0, 0, 0], [0, 0, 0, 0], [1, 0, 0, 0], [1, 1, 0, 0] ]) # ArithmeticOnlyMatrix tests def test_abs(): m = ArithmeticOnlyMatrix([[1, -2], [x, y]]) assert abs(m) == ArithmeticOnlyMatrix([[1, 2], [Abs(x), Abs(y)]]) def test_add(): m = ArithmeticOnlyMatrix([[1, 2, 3], [x, y, x], [2*y, -50, z*x]]) assert m + m == ArithmeticOnlyMatrix([[2, 4, 6], [2*x, 2*y, 2*x], [4*y, -100, 2*z*x]]) n = ArithmeticOnlyMatrix(1, 2, [1, 2]) raises(ShapeError, lambda: m + n) def test_multiplication(): a = ArithmeticOnlyMatrix(( (1, 2), (3, 1), (0, 6), )) b = ArithmeticOnlyMatrix(( (1, 2), (3, 0), )) raises(ShapeError, lambda: b*a) raises(TypeError, lambda: a*{}) c = a*b assert c[0, 0] == 7 assert c[0, 1] == 2 assert c[1, 0] == 6 assert c[1, 1] == 6 assert c[2, 0] == 18 assert c[2, 1] == 0 try: eval('c = a @ b') except SyntaxError: pass else: assert c[0, 0] == 7 assert c[0, 1] == 2 assert c[1, 0] == 6 assert c[1, 1] == 6 assert c[2, 0] == 18 assert c[2, 1] == 0 h = a.multiply_elementwise(c) assert h == matrix_multiply_elementwise(a, c) assert h[0, 0] == 7 assert h[0, 1] == 4 assert h[1, 0] == 18 assert h[1, 1] == 6 assert h[2, 0] == 0 assert h[2, 1] == 0 raises(ShapeError, lambda: a.multiply_elementwise(b)) c = b * Symbol("x") assert isinstance(c, ArithmeticOnlyMatrix) assert c[0, 0] == x assert c[0, 1] == 2*x assert c[1, 0] == 3*x assert c[1, 1] == 0 c2 = x * b assert c == c2 c = 5 * b assert isinstance(c, ArithmeticOnlyMatrix) assert c[0, 0] == 5 assert c[0, 1] == 2*5 assert c[1, 0] == 3*5 assert c[1, 1] == 0 try: eval('c = 5 @ b') except SyntaxError: pass else: assert isinstance(c, ArithmeticOnlyMatrix) assert c[0, 0] == 5 assert c[0, 1] == 2*5 assert c[1, 0] == 3*5 assert c[1, 1] == 0 def test_matmul(): a = Matrix([[1, 2], [3, 4]]) assert a.__matmul__(2) == NotImplemented assert a.__rmatmul__(2) == NotImplemented #This is done this way because @ is only supported in Python 3.5+ #To check 2@a case try: eval('2 @ a') except SyntaxError: pass except TypeError: #TypeError is raised in case of NotImplemented is returned pass #Check a@2 case try: eval('a @ 2') except SyntaxError: pass except TypeError: #TypeError is raised in case of NotImplemented is returned pass def test_non_matmul(): """ Test that if explicitly specified as non-matrix, mul reverts to scalar multiplication. """ class foo(Expr): is_Matrix=False is_MatrixLike=False shape = (1, 1) A = Matrix([[1, 2], [3, 4]]) b = foo() assert b*A == Matrix([[b, 2*b], [3*b, 4*b]]) assert A*b == Matrix([[b, 2*b], [3*b, 4*b]]) def test_power(): raises(NonSquareMatrixError, lambda: Matrix((1, 2))**2) A = ArithmeticOnlyMatrix([[2, 3], [4, 5]]) assert (A**5)[:] == (6140, 8097, 10796, 14237) A = ArithmeticOnlyMatrix([[2, 1, 3], [4, 2, 4], [6, 12, 1]]) assert (A**3)[:] == (290, 262, 251, 448, 440, 368, 702, 954, 433) assert A**0 == eye(3) assert A**1 == A assert (ArithmeticOnlyMatrix([[2]]) ** 100)[0, 0] == 2**100 assert ArithmeticOnlyMatrix([[1, 2], [3, 4]])**Integer(2) == ArithmeticOnlyMatrix([[7, 10], [15, 22]]) A = Matrix([[1,2],[4,5]]) assert A.pow(20, method='cayley') == A.pow(20, method='multiply') def test_neg(): n = ArithmeticOnlyMatrix(1, 2, [1, 2]) assert -n == ArithmeticOnlyMatrix(1, 2, [-1, -2]) def test_sub(): n = ArithmeticOnlyMatrix(1, 2, [1, 2]) assert n - n == ArithmeticOnlyMatrix(1, 2, [0, 0]) def test_div(): n = ArithmeticOnlyMatrix(1, 2, [1, 2]) assert n/2 == ArithmeticOnlyMatrix(1, 2, [S.Half, S(2)/2]) # SpecialOnlyMatrix tests def test_eye(): assert list(SpecialOnlyMatrix.eye(2, 2)) == [1, 0, 0, 1] assert list(SpecialOnlyMatrix.eye(2)) == [1, 0, 0, 1] assert type(SpecialOnlyMatrix.eye(2)) == SpecialOnlyMatrix assert type(SpecialOnlyMatrix.eye(2, cls=Matrix)) == Matrix def test_ones(): assert list(SpecialOnlyMatrix.ones(2, 2)) == [1, 1, 1, 1] assert list(SpecialOnlyMatrix.ones(2)) == [1, 1, 1, 1] assert SpecialOnlyMatrix.ones(2, 3) == Matrix([[1, 1, 1], [1, 1, 1]]) assert type(SpecialOnlyMatrix.ones(2)) == SpecialOnlyMatrix assert type(SpecialOnlyMatrix.ones(2, cls=Matrix)) == Matrix def test_zeros(): assert list(SpecialOnlyMatrix.zeros(2, 2)) == [0, 0, 0, 0] assert list(SpecialOnlyMatrix.zeros(2)) == [0, 0, 0, 0] assert SpecialOnlyMatrix.zeros(2, 3) == Matrix([[0, 0, 0], [0, 0, 0]]) assert type(SpecialOnlyMatrix.zeros(2)) == SpecialOnlyMatrix assert type(SpecialOnlyMatrix.zeros(2, cls=Matrix)) == Matrix def test_diag_make(): diag = SpecialOnlyMatrix.diag a = Matrix([[1, 2], [2, 3]]) b = Matrix([[3, x], [y, 3]]) c = Matrix([[3, x, 3], [y, 3, z], [x, y, z]]) assert diag(a, b, b) == Matrix([ [1, 2, 0, 0, 0, 0], [2, 3, 0, 0, 0, 0], [0, 0, 3, x, 0, 0], [0, 0, y, 3, 0, 0], [0, 0, 0, 0, 3, x], [0, 0, 0, 0, y, 3], ]) assert diag(a, b, c) == Matrix([ [1, 2, 0, 0, 0, 0, 0], [2, 3, 0, 0, 0, 0, 0], [0, 0, 3, x, 0, 0, 0], [0, 0, y, 3, 0, 0, 0], [0, 0, 0, 0, 3, x, 3], [0, 0, 0, 0, y, 3, z], [0, 0, 0, 0, x, y, z], ]) assert diag(a, c, b) == Matrix([ [1, 2, 0, 0, 0, 0, 0], [2, 3, 0, 0, 0, 0, 0], [0, 0, 3, x, 3, 0, 0], [0, 0, y, 3, z, 0, 0], [0, 0, x, y, z, 0, 0], [0, 0, 0, 0, 0, 3, x], [0, 0, 0, 0, 0, y, 3], ]) a = Matrix([x, y, z]) b = Matrix([[1, 2], [3, 4]]) c = Matrix([[5, 6]]) # this "wandering diagonal" is what makes this # a block diagonal where each block is independent # of the others assert diag(a, 7, b, c) == Matrix([ [x, 0, 0, 0, 0, 0], [y, 0, 0, 0, 0, 0], [z, 0, 0, 0, 0, 0], [0, 7, 0, 0, 0, 0], [0, 0, 1, 2, 0, 0], [0, 0, 3, 4, 0, 0], [0, 0, 0, 0, 5, 6]]) raises(ValueError, lambda: diag(a, 7, b, c, rows=5)) assert diag(1) == Matrix([[1]]) assert diag(1, rows=2) == Matrix([[1, 0], [0, 0]]) assert diag(1, cols=2) == Matrix([[1, 0], [0, 0]]) assert diag(1, rows=3, cols=2) == Matrix([[1, 0], [0, 0], [0, 0]]) assert diag(*[2, 3]) == Matrix([ [2, 0], [0, 3]]) assert diag(Matrix([2, 3])) == Matrix([ [2], [3]]) assert diag([1, [2, 3], 4], unpack=False) == \ diag([[1], [2, 3], [4]], unpack=False) == Matrix([ [1, 0], [2, 3], [4, 0]]) assert type(diag(1)) == SpecialOnlyMatrix assert type(diag(1, cls=Matrix)) == Matrix assert Matrix.diag([1, 2, 3]) == Matrix.diag(1, 2, 3) assert Matrix.diag([1, 2, 3], unpack=False).shape == (3, 1) assert Matrix.diag([[1, 2, 3]]).shape == (3, 1) assert Matrix.diag([[1, 2, 3]], unpack=False).shape == (1, 3) assert Matrix.diag([[[1, 2, 3]]]).shape == (1, 3) # kerning can be used to move the starting point assert Matrix.diag(ones(0, 2), 1, 2) == Matrix([ [0, 0, 1, 0], [0, 0, 0, 2]]) assert Matrix.diag(ones(2, 0), 1, 2) == Matrix([ [0, 0], [0, 0], [1, 0], [0, 2]]) def test_diagonal(): m = Matrix(3, 3, range(9)) d = m.diagonal() assert d == m.diagonal(0) assert tuple(d) == (0, 4, 8) assert tuple(m.diagonal(1)) == (1, 5) assert tuple(m.diagonal(-1)) == (3, 7) assert tuple(m.diagonal(2)) == (2,) assert type(m.diagonal()) == type(m) s = SparseMatrix(3, 3, {(1, 1): 1}) assert type(s.diagonal()) == type(s) assert type(m) != type(s) raises(ValueError, lambda: m.diagonal(3)) raises(ValueError, lambda: m.diagonal(-3)) raises(ValueError, lambda: m.diagonal(pi)) M = ones(2, 3) assert banded({i: list(M.diagonal(i)) for i in range(1-M.rows, M.cols)}) == M def test_jordan_block(): assert SpecialOnlyMatrix.jordan_block(3, 2) == SpecialOnlyMatrix.jordan_block(3, eigenvalue=2) \ == SpecialOnlyMatrix.jordan_block(size=3, eigenvalue=2) \ == SpecialOnlyMatrix.jordan_block(3, 2, band='upper') \ == SpecialOnlyMatrix.jordan_block( size=3, eigenval=2, eigenvalue=2) \ == Matrix([ [2, 1, 0], [0, 2, 1], [0, 0, 2]]) assert SpecialOnlyMatrix.jordan_block(3, 2, band='lower') == Matrix([ [2, 0, 0], [1, 2, 0], [0, 1, 2]]) # missing eigenvalue raises(ValueError, lambda: SpecialOnlyMatrix.jordan_block(2)) # non-integral size raises(ValueError, lambda: SpecialOnlyMatrix.jordan_block(3.5, 2)) # size not specified raises(ValueError, lambda: SpecialOnlyMatrix.jordan_block(eigenvalue=2)) # inconsistent eigenvalue raises(ValueError, lambda: SpecialOnlyMatrix.jordan_block( eigenvalue=2, eigenval=4)) # Deprecated feature with warns_deprecated_sympy(): assert (SpecialOnlyMatrix.jordan_block(cols=3, eigenvalue=2) == SpecialOnlyMatrix(3, 3, (2, 1, 0, 0, 2, 1, 0, 0, 2))) with warns_deprecated_sympy(): assert (SpecialOnlyMatrix.jordan_block(rows=3, eigenvalue=2) == SpecialOnlyMatrix(3, 3, (2, 1, 0, 0, 2, 1, 0, 0, 2))) with warns_deprecated_sympy(): assert SpecialOnlyMatrix.jordan_block(3, 2) == \ SpecialOnlyMatrix.jordan_block(cols=3, eigenvalue=2) == \ SpecialOnlyMatrix.jordan_block(rows=3, eigenvalue=2) with warns_deprecated_sympy(): assert SpecialOnlyMatrix.jordan_block( rows=4, cols=3, eigenvalue=2) == \ Matrix([ [2, 1, 0], [0, 2, 1], [0, 0, 2], [0, 0, 0]]) # Using alias keyword assert SpecialOnlyMatrix.jordan_block(size=3, eigenvalue=2) == \ SpecialOnlyMatrix.jordan_block(size=3, eigenval=2) def test_orthogonalize(): m = Matrix([[1, 2], [3, 4]]) assert m.orthogonalize(Matrix([[2], [1]])) == [Matrix([[2], [1]])] assert m.orthogonalize(Matrix([[2], [1]]), normalize=True) == \ [Matrix([[2*sqrt(5)/5], [sqrt(5)/5]])] assert m.orthogonalize(Matrix([[1], [2]]), Matrix([[-1], [4]])) == \ [Matrix([[1], [2]]), Matrix([[Rational(-12, 5)], [Rational(6, 5)]])] assert m.orthogonalize(Matrix([[0], [0]]), Matrix([[-1], [4]])) == \ [Matrix([[-1], [4]])] assert m.orthogonalize(Matrix([[0], [0]])) == [] n = Matrix([[9, 1, 9], [3, 6, 10], [8, 5, 2]]) vecs = [Matrix([[-5], [1]]), Matrix([[-5], [2]]), Matrix([[-5], [-2]])] assert n.orthogonalize(*vecs) == \ [Matrix([[-5], [1]]), Matrix([[Rational(5, 26)], [Rational(25, 26)]])] vecs = [Matrix([0, 0, 0]), Matrix([1, 2, 3]), Matrix([1, 4, 5])] raises(ValueError, lambda: Matrix.orthogonalize(*vecs, rankcheck=True)) vecs = [Matrix([1, 2, 3]), Matrix([4, 5, 6]), Matrix([7, 8, 9])] raises(ValueError, lambda: Matrix.orthogonalize(*vecs, rankcheck=True)) def test_wilkinson(): wminus, wplus = Matrix.wilkinson(1) assert wminus == Matrix([ [-1, 1, 0], [1, 0, 1], [0, 1, 1]]) assert wplus == Matrix([ [1, 1, 0], [1, 0, 1], [0, 1, 1]]) wminus, wplus = Matrix.wilkinson(3) assert wminus == Matrix([ [-3, 1, 0, 0, 0, 0, 0], [1, -2, 1, 0, 0, 0, 0], [0, 1, -1, 1, 0, 0, 0], [0, 0, 1, 0, 1, 0, 0], [0, 0, 0, 1, 1, 1, 0], [0, 0, 0, 0, 1, 2, 1], [0, 0, 0, 0, 0, 1, 3]]) assert wplus == Matrix([ [3, 1, 0, 0, 0, 0, 0], [1, 2, 1, 0, 0, 0, 0], [0, 1, 1, 1, 0, 0, 0], [0, 0, 1, 0, 1, 0, 0], [0, 0, 0, 1, 1, 1, 0], [0, 0, 0, 0, 1, 2, 1], [0, 0, 0, 0, 0, 1, 3]]) # CalculusOnlyMatrix tests @XFAIL def test_diff(): x, y = symbols('x y') m = CalculusOnlyMatrix(2, 1, [x, y]) # TODO: currently not working as ``_MinimalMatrix`` cannot be sympified: assert m.diff(x) == Matrix(2, 1, [1, 0]) def test_integrate(): x, y = symbols('x y') m = CalculusOnlyMatrix(2, 1, [x, y]) assert m.integrate(x) == Matrix(2, 1, [x**2/2, y*x]) def test_jacobian2(): rho, phi = symbols("rho,phi") X = CalculusOnlyMatrix(3, 1, [rho*cos(phi), rho*sin(phi), rho**2]) Y = CalculusOnlyMatrix(2, 1, [rho, phi]) J = Matrix([ [cos(phi), -rho*sin(phi)], [sin(phi), rho*cos(phi)], [ 2*rho, 0], ]) assert X.jacobian(Y) == J m = CalculusOnlyMatrix(2, 2, [1, 2, 3, 4]) m2 = CalculusOnlyMatrix(4, 1, [1, 2, 3, 4]) raises(TypeError, lambda: m.jacobian(Matrix([1, 2]))) raises(TypeError, lambda: m2.jacobian(m)) def test_limit(): x, y = symbols('x y') m = CalculusOnlyMatrix(2, 1, [1/x, y]) assert m.limit(x, 5) == Matrix(2, 1, [Rational(1, 5), y]) def test_issue_13774(): M = Matrix([[1, 2, 3], [4, 5, 6], [7, 8, 9]]) v = [1, 1, 1] raises(TypeError, lambda: M*v) raises(TypeError, lambda: v*M) def test_companion(): x = Symbol('x') y = Symbol('y') raises(ValueError, lambda: Matrix.companion(1)) raises(ValueError, lambda: Matrix.companion(Poly([1], x))) raises(ValueError, lambda: Matrix.companion(Poly([2, 1], x))) raises(ValueError, lambda: Matrix.companion(Poly(x*y, [x, y]))) c0, c1, c2 = symbols('c0:3') assert Matrix.companion(Poly([1, c0], x)) == Matrix([-c0]) assert Matrix.companion(Poly([1, c1, c0], x)) == \ Matrix([[0, -c0], [1, -c1]]) assert Matrix.companion(Poly([1, c2, c1, c0], x)) == \ Matrix([[0, 0, -c0], [1, 0, -c1], [0, 1, -c2]]) def test_issue_10589(): x, y, z = symbols("x, y z") M1 = Matrix([x, y, z]) M1 = M1.subs(zip([x, y, z], [1, 2, 3])) assert M1 == Matrix([[1], [2], [3]]) M2 = Matrix([[x, x, x, x, x], [x, x, x, x, x], [x, x, x, x, x]]) M2 = M2.subs(zip([x], [1])) assert M2 == Matrix([[1, 1, 1, 1, 1], [1, 1, 1, 1, 1], [1, 1, 1, 1, 1]]) def test_rmul_pr19860(): class Foo(ImmutableDenseMatrix): _op_priority = MutableDenseMatrix._op_priority + 0.01 a = Matrix(2, 2, [1, 2, 3, 4]) b = Foo(2, 2, [1, 2, 3, 4]) # This would throw a RecursionError: maximum recursion depth # since b always has higher priority even after a.as_mutable() c = a*b assert isinstance(c, Foo) assert c == Matrix([[7, 10], [15, 22]]) def test_issue_18956(): A = Array([[1, 2], [3, 4]]) B = Matrix([[1,2],[3,4]]) raises(TypeError, lambda: B + A) raises(TypeError, lambda: A + B)
7247c60c283633a825baff571677d44606bc8317761d32fb697dbcd6ceb0cba7
from sympy.combinatorics import Permutation from sympy.core.symbol import symbols from sympy.matrices import Matrix from sympy.matrices.expressions import ( PermutationMatrix, BlockDiagMatrix, BlockMatrix) def test_connected_components(): a, b, c, d, e, f, g, h, i, j, k, l, m = symbols('a:m') M = Matrix([ [a, 0, 0, 0, b, 0, 0, 0, 0, 0, c, 0, 0], [0, d, 0, 0, 0, e, 0, 0, 0, 0, 0, f, 0], [0, 0, g, 0, 0, 0, h, 0, 0, 0, 0, 0, i], [0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0], [m, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0], [0, m, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0], [0, 0, m, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0], [j, 0, 0, 0, k, 0, 0, 1, 0, 0, l, 0, 0], [0, j, 0, 0, 0, k, 0, 0, 1, 0, 0, l, 0], [0, 0, j, 0, 0, 0, k, 0, 0, 1, 0, 0, l], [0, 0, 0, 0, d, 0, 0, 0, 0, 0, 1, 0, 0], [0, 0, 0, 0, 0, d, 0, 0, 0, 0, 0, 1, 0], [0, 0, 0, 0, 0, 0, d, 0, 0, 0, 0, 0, 1]]) cc = M.connected_components() assert cc == [[0, 4, 7, 10], [1, 5, 8, 11], [2, 6, 9, 12], [3]] P, B = M.connected_components_decomposition() p = Permutation([0, 4, 7, 10, 1, 5, 8, 11, 2, 6, 9, 12, 3]) assert P == PermutationMatrix(p) B0 = Matrix([ [a, b, 0, c], [m, 1, 0, 0], [j, k, 1, l], [0, d, 0, 1]]) B1 = Matrix([ [d, e, 0, f], [m, 1, 0, 0], [j, k, 1, l], [0, d, 0, 1]]) B2 = Matrix([ [g, h, 0, i], [m, 1, 0, 0], [j, k, 1, l], [0, d, 0, 1]]) B3 = Matrix([[1]]) assert B == BlockDiagMatrix(B0, B1, B2, B3) def test_strongly_connected_components(): M = Matrix([ [11, 14, 10, 0, 15, 0], [0, 44, 0, 0, 45, 0], [1, 4, 0, 0, 5, 0], [0, 0, 0, 22, 0, 23], [0, 54, 0, 0, 55, 0], [0, 0, 0, 32, 0, 33]]) scc = M.strongly_connected_components() assert scc == [[1, 4], [0, 2], [3, 5]] P, B = M.strongly_connected_components_decomposition() p = Permutation([1, 4, 0, 2, 3, 5]) assert P == PermutationMatrix(p) assert B == BlockMatrix([ [ Matrix([[44, 45], [54, 55]]), Matrix.zeros(2, 2), Matrix.zeros(2, 2) ], [ Matrix([[14, 15], [4, 5]]), Matrix([[11, 10], [1, 0]]), Matrix.zeros(2, 2) ], [ Matrix.zeros(2, 2), Matrix.zeros(2, 2), Matrix([[22, 23], [32, 33]]) ] ]) P = P.as_explicit() B = B.as_explicit() assert P.T * B * P == M P, B = M.strongly_connected_components_decomposition(lower=False) p = Permutation([3, 5, 0, 2, 1, 4]) assert P == PermutationMatrix(p) assert B == BlockMatrix([ [ Matrix([[22, 23], [32, 33]]), Matrix.zeros(2, 2), Matrix.zeros(2, 2) ], [ Matrix.zeros(2, 2), Matrix([[11, 10], [1, 0]]), Matrix([[14, 15], [4, 5]]) ], [ Matrix.zeros(2, 2), Matrix.zeros(2, 2), Matrix([[44, 45], [54, 55]]) ] ]) P = P.as_explicit() B = B.as_explicit() assert P.T * B * P == M
e3ded36995b15fa83bb8e9ba8c2c1b2d1d0008ca3f909fd148b29bb61c83826d
import random from sympy.core.numbers import I from sympy import symbols, Symbol, Rational, sqrt, Poly from sympy.matrices import Matrix, eye, ones from sympy.abc import x, y, z from sympy.testing.pytest import raises from sympy.matrices.common import NonSquareMatrixError from sympy.functions.combinatorial.factorials import factorial, subfactorial def test_determinant(): for M in [Matrix(), Matrix([[1]])]: assert ( M.det() == M._eval_det_bareiss() == M._eval_det_berkowitz() == M._eval_det_lu() == 1) M = Matrix(( (-3, 2), ( 8, -5) )) assert M.det(method="domain-ge") == -1 assert M.det(method="bareiss") == -1 assert M.det(method="berkowitz") == -1 assert M.det(method="lu") == -1 M = Matrix(( (x, 1), (y, 2*y) )) assert M.det(method="domain-ge") == 2*x*y - y assert M.det(method="bareiss") == 2*x*y - y assert M.det(method="berkowitz") == 2*x*y - y assert M.det(method="lu") == 2*x*y - y M = Matrix(( (1, 1, 1), (1, 2, 3), (1, 3, 6) )) assert M.det(method="domain-ge") == 1 assert M.det(method="bareiss") == 1 assert M.det(method="berkowitz") == 1 assert M.det(method="lu") == 1 M = Matrix(( ( 3, -2, 0, 5), (-2, 1, -2, 2), ( 0, -2, 5, 0), ( 5, 0, 3, 4) )) assert M.det(method="domain-ge") == -289 assert M.det(method="bareiss") == -289 assert M.det(method="berkowitz") == -289 assert M.det(method="lu") == -289 M = Matrix(( ( 1, 2, 3, 4), ( 5, 6, 7, 8), ( 9, 10, 11, 12), (13, 14, 15, 16) )) assert M.det(method="domain-ge") == 0 assert M.det(method="bareiss") == 0 assert M.det(method="berkowitz") == 0 assert M.det(method="lu") == 0 M = Matrix(( (3, 2, 0, 0, 0), (0, 3, 2, 0, 0), (0, 0, 3, 2, 0), (0, 0, 0, 3, 2), (2, 0, 0, 0, 3) )) assert M.det(method="domain-ge") == 275 assert M.det(method="bareiss") == 275 assert M.det(method="berkowitz") == 275 assert M.det(method="lu") == 275 M = Matrix(( ( 3, 0, 0, 0), (-2, 1, 0, 0), ( 0, -2, 5, 0), ( 5, 0, 3, 4) )) assert M.det(method="domain-ge") == 60 assert M.det(method="bareiss") == 60 assert M.det(method="berkowitz") == 60 assert M.det(method="lu") == 60 M = Matrix(( ( 1, 0, 0, 0), ( 5, 0, 0, 0), ( 9, 10, 11, 0), (13, 14, 15, 16) )) assert M.det(method="domain-ge") == 0 assert M.det(method="bareiss") == 0 assert M.det(method="berkowitz") == 0 assert M.det(method="lu") == 0 M = Matrix(( (3, 2, 0, 0, 0), (0, 3, 2, 0, 0), (0, 0, 3, 2, 0), (0, 0, 0, 3, 2), (0, 0, 0, 0, 3) )) assert M.det(method="domain-ge") == 243 assert M.det(method="bareiss") == 243 assert M.det(method="berkowitz") == 243 assert M.det(method="lu") == 243 M = Matrix(( (1, 0, 1, 2, 12), (2, 0, 1, 1, 4), (2, 1, 1, -1, 3), (3, 2, -1, 1, 8), (1, 1, 1, 0, 6) )) assert M.det(method="domain-ge") == -55 assert M.det(method="bareiss") == -55 assert M.det(method="berkowitz") == -55 assert M.det(method="lu") == -55 M = Matrix(( (-5, 2, 3, 4, 5), ( 1, -4, 3, 4, 5), ( 1, 2, -3, 4, 5), ( 1, 2, 3, -2, 5), ( 1, 2, 3, 4, -1) )) assert M.det(method="domain-ge") == 11664 assert M.det(method="bareiss") == 11664 assert M.det(method="berkowitz") == 11664 assert M.det(method="lu") == 11664 M = Matrix(( ( 2, 7, -1, 3, 2), ( 0, 0, 1, 0, 1), (-2, 0, 7, 0, 2), (-3, -2, 4, 5, 3), ( 1, 0, 0, 0, 1) )) assert M.det(method="domain-ge") == 123 assert M.det(method="bareiss") == 123 assert M.det(method="berkowitz") == 123 assert M.det(method="lu") == 123 M = Matrix(( (x, y, z), (1, 0, 0), (y, z, x) )) assert M.det(method="domain-ge") == z**2 - x*y assert M.det(method="bareiss") == z**2 - x*y assert M.det(method="berkowitz") == z**2 - x*y assert M.det(method="lu") == z**2 - x*y # issue 13835 a = symbols('a') M = lambda n: Matrix([[i + a*j for i in range(n)] for j in range(n)]) assert M(5).det() == 0 assert M(6).det() == 0 assert M(7).det() == 0 def test_issue_14517(): M = Matrix([ [ 0, 10*I, 10*I, 0], [10*I, 0, 0, 10*I], [10*I, 0, 5 + 2*I, 10*I], [ 0, 10*I, 10*I, 5 + 2*I]]) ev = M.eigenvals() # test one random eigenvalue, the computation is a little slow test_ev = random.choice(list(ev.keys())) assert (M - test_ev*eye(4)).det() == 0 def test_legacy_det(): # Minimal support for legacy keys for 'method' in det() # Partially copied from test_determinant() M = Matrix(( ( 3, -2, 0, 5), (-2, 1, -2, 2), ( 0, -2, 5, 0), ( 5, 0, 3, 4) )) assert M.det(method="bareis") == -289 assert M.det(method="det_lu") == -289 assert M.det(method="det_LU") == -289 M = Matrix(( (3, 2, 0, 0, 0), (0, 3, 2, 0, 0), (0, 0, 3, 2, 0), (0, 0, 0, 3, 2), (2, 0, 0, 0, 3) )) assert M.det(method="bareis") == 275 assert M.det(method="det_lu") == 275 assert M.det(method="Bareis") == 275 M = Matrix(( (1, 0, 1, 2, 12), (2, 0, 1, 1, 4), (2, 1, 1, -1, 3), (3, 2, -1, 1, 8), (1, 1, 1, 0, 6) )) assert M.det(method="bareis") == -55 assert M.det(method="det_lu") == -55 assert M.det(method="BAREISS") == -55 M = Matrix(( ( 3, 0, 0, 0), (-2, 1, 0, 0), ( 0, -2, 5, 0), ( 5, 0, 3, 4) )) assert M.det(method="bareiss") == 60 assert M.det(method="berkowitz") == 60 assert M.det(method="lu") == 60 M = Matrix(( ( 1, 0, 0, 0), ( 5, 0, 0, 0), ( 9, 10, 11, 0), (13, 14, 15, 16) )) assert M.det(method="bareiss") == 0 assert M.det(method="berkowitz") == 0 assert M.det(method="lu") == 0 M = Matrix(( (3, 2, 0, 0, 0), (0, 3, 2, 0, 0), (0, 0, 3, 2, 0), (0, 0, 0, 3, 2), (0, 0, 0, 0, 3) )) assert M.det(method="bareiss") == 243 assert M.det(method="berkowitz") == 243 assert M.det(method="lu") == 243 M = Matrix(( (-5, 2, 3, 4, 5), ( 1, -4, 3, 4, 5), ( 1, 2, -3, 4, 5), ( 1, 2, 3, -2, 5), ( 1, 2, 3, 4, -1) )) assert M.det(method="bareis") == 11664 assert M.det(method="det_lu") == 11664 assert M.det(method="BERKOWITZ") == 11664 M = Matrix(( ( 2, 7, -1, 3, 2), ( 0, 0, 1, 0, 1), (-2, 0, 7, 0, 2), (-3, -2, 4, 5, 3), ( 1, 0, 0, 0, 1) )) assert M.det(method="bareis") == 123 assert M.det(method="det_lu") == 123 assert M.det(method="LU") == 123 def eye_Determinant(n): return Matrix(n, n, lambda i, j: int(i == j)) def zeros_Determinant(n): return Matrix(n, n, lambda i, j: 0) def test_det(): a = Matrix(2, 3, [1, 2, 3, 4, 5, 6]) raises(NonSquareMatrixError, lambda: a.det()) z = zeros_Determinant(2) ey = eye_Determinant(2) assert z.det() == 0 assert ey.det() == 1 x = Symbol('x') a = Matrix(0, 0, []) b = Matrix(1, 1, [5]) c = Matrix(2, 2, [1, 2, 3, 4]) d = Matrix(3, 3, [1, 2, 3, 4, 5, 6, 7, 8, 8]) e = Matrix(4, 4, [x, 1, 2, 3, 4, 5, 6, 7, 2, 9, 10, 11, 12, 13, 14, 14]) from sympy.abc import i, j, k, l, m, n f = Matrix(3, 3, [i, l, m, 0, j, n, 0, 0, k]) g = Matrix(3, 3, [i, 0, 0, l, j, 0, m, n, k]) h = Matrix(3, 3, [x**3, 0, 0, i, x**-1, 0, j, k, x**-2]) # the method keyword for `det` doesn't kick in until 4x4 matrices, # so there is no need to test all methods on smaller ones assert a.det() == 1 assert b.det() == 5 assert c.det() == -2 assert d.det() == 3 assert e.det() == 4*x - 24 assert e.det(method="domain-ge") == 4*x - 24 assert e.det(method='bareiss') == 4*x - 24 assert e.det(method='berkowitz') == 4*x - 24 assert f.det() == i*j*k assert g.det() == i*j*k assert h.det() == 1 raises(ValueError, lambda: e.det(iszerofunc="test")) def test_permanent(): M = Matrix([[1, 2, 3], [4, 5, 6], [7, 8, 9]]) assert M.per() == 450 for i in range(1, 12): assert ones(i, i).per() == ones(i, i).T.per() == factorial(i) assert (ones(i, i)-eye(i)).per() == (ones(i, i)-eye(i)).T.per() == subfactorial(i) a1, a2, a3, a4, a5 = symbols('a_1 a_2 a_3 a_4 a_5') M = Matrix([a1, a2, a3, a4, a5]) assert M.per() == M.T.per() == a1 + a2 + a3 + a4 + a5 def test_adjugate(): x = Symbol('x') e = Matrix(4, 4, [x, 1, 2, 3, 4, 5, 6, 7, 2, 9, 10, 11, 12, 13, 14, 14]) adj = Matrix([ [ 4, -8, 4, 0], [ 76, -14*x - 68, 14*x - 8, -4*x + 24], [-122, 17*x + 142, -21*x + 4, 8*x - 48], [ 48, -4*x - 72, 8*x, -4*x + 24]]) assert e.adjugate() == adj assert e.adjugate(method='bareiss') == adj assert e.adjugate(method='berkowitz') == adj a = Matrix(2, 3, [1, 2, 3, 4, 5, 6]) raises(NonSquareMatrixError, lambda: a.adjugate()) def test_util(): R = Rational v1 = Matrix(1, 3, [1, 2, 3]) v2 = Matrix(1, 3, [3, 4, 5]) assert v1.norm() == sqrt(14) assert v1.project(v2) == Matrix(1, 3, [R(39)/25, R(52)/25, R(13)/5]) assert Matrix.zeros(1, 2) == Matrix(1, 2, [0, 0]) assert ones(1, 2) == Matrix(1, 2, [1, 1]) assert v1.copy() == v1 # cofactor assert eye(3) == eye(3).cofactor_matrix() test = Matrix([[1, 3, 2], [2, 6, 3], [2, 3, 6]]) assert test.cofactor_matrix() == \ Matrix([[27, -6, -6], [-12, 2, 3], [-3, 1, 0]]) test = Matrix([[1, 2, 3], [4, 5, 6], [7, 8, 9]]) assert test.cofactor_matrix() == \ Matrix([[-3, 6, -3], [6, -12, 6], [-3, 6, -3]]) def test_cofactor_and_minors(): x = Symbol('x') e = Matrix(4, 4, [x, 1, 2, 3, 4, 5, 6, 7, 2, 9, 10, 11, 12, 13, 14, 14]) m = Matrix([ [ x, 1, 3], [ 2, 9, 11], [12, 13, 14]]) cm = Matrix([ [ 4, 76, -122, 48], [-8, -14*x - 68, 17*x + 142, -4*x - 72], [ 4, 14*x - 8, -21*x + 4, 8*x], [ 0, -4*x + 24, 8*x - 48, -4*x + 24]]) sub = Matrix([ [x, 1, 2], [4, 5, 6], [2, 9, 10]]) assert e.minor_submatrix(1, 2) == m assert e.minor_submatrix(-1, -1) == sub assert e.minor(1, 2) == -17*x - 142 assert e.cofactor(1, 2) == 17*x + 142 assert e.cofactor_matrix() == cm assert e.cofactor_matrix(method="bareiss") == cm assert e.cofactor_matrix(method="berkowitz") == cm raises(ValueError, lambda: e.cofactor(4, 5)) raises(ValueError, lambda: e.minor(4, 5)) raises(ValueError, lambda: e.minor_submatrix(4, 5)) a = Matrix(2, 3, [1, 2, 3, 4, 5, 6]) assert a.minor_submatrix(0, 0) == Matrix([[5, 6]]) raises(ValueError, lambda: Matrix(0, 0, []).minor_submatrix(0, 0)) raises(NonSquareMatrixError, lambda: a.cofactor(0, 0)) raises(NonSquareMatrixError, lambda: a.minor(0, 0)) raises(NonSquareMatrixError, lambda: a.cofactor_matrix()) def test_charpoly(): x, y = Symbol('x'), Symbol('y') z, t = Symbol('z'), Symbol('t') from sympy.abc import a,b,c m = Matrix(3, 3, [1, 2, 3, 4, 5, 6, 7, 8, 9]) assert eye_Determinant(3).charpoly(x) == Poly((x - 1)**3, x) assert eye_Determinant(3).charpoly(y) == Poly((y - 1)**3, y) assert m.charpoly() == Poly(x**3 - 15*x**2 - 18*x, x) raises(NonSquareMatrixError, lambda: Matrix([[1], [2]]).charpoly()) n = Matrix(4, 4, [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]) assert n.charpoly() == Poly(x**4, x) n = Matrix(4, 4, [45, 0, 0, 0, 0, 23, 0, 0, 0, 0, 87, 0, 0, 0, 0, 12]) assert n.charpoly() == Poly(x**4 - 167*x**3 + 8811*x**2 - 173457*x + 1080540, x) n = Matrix(3, 3, [x, 0, 0, a, y, 0, b, c, z]) assert n.charpoly() == Poly(t**3 - (x+y+z)*t**2 + t*(x*y+y*z+x*z) - x*y*z , t)
88bdf8e6704199b8ddc434d18133064633ee212c39efa4731f230aa08d05bd6a
from sympy import Rational, I, expand_mul, S, simplify, sqrt from sympy.matrices.matrices import NonSquareMatrixError from sympy.matrices import Matrix, zeros, eye, SparseMatrix from sympy.abc import x, y, z from sympy.testing.pytest import raises, slow from sympy.testing.matrices import allclose def test_LUdecomp(): testmat = Matrix([[0, 2, 5, 3], [3, 3, 7, 4], [8, 4, 0, 2], [-2, 6, 3, 4]]) L, U, p = testmat.LUdecomposition() assert L.is_lower assert U.is_upper assert (L*U).permute_rows(p, 'backward') - testmat == zeros(4) testmat = Matrix([[6, -2, 7, 4], [0, 3, 6, 7], [1, -2, 7, 4], [-9, 2, 6, 3]]) L, U, p = testmat.LUdecomposition() assert L.is_lower assert U.is_upper assert (L*U).permute_rows(p, 'backward') - testmat == zeros(4) # non-square testmat = Matrix([[1, 2, 3], [4, 5, 6], [7, 8, 9], [10, 11, 12]]) L, U, p = testmat.LUdecomposition(rankcheck=False) assert L.is_lower assert U.is_upper assert (L*U).permute_rows(p, 'backward') - testmat == zeros(4, 3) # square and singular testmat = Matrix([[1, 2, 3], [2, 4, 6], [4, 5, 6]]) L, U, p = testmat.LUdecomposition(rankcheck=False) assert L.is_lower assert U.is_upper assert (L*U).permute_rows(p, 'backward') - testmat == zeros(3) M = Matrix(((1, x, 1), (2, y, 0), (y, 0, z))) L, U, p = M.LUdecomposition() assert L.is_lower assert U.is_upper assert (L*U).permute_rows(p, 'backward') - M == zeros(3) mL = Matrix(( (1, 0, 0), (2, 3, 0), )) assert mL.is_lower is True assert mL.is_upper is False mU = Matrix(( (1, 2, 3), (0, 4, 5), )) assert mU.is_lower is False assert mU.is_upper is True # test FF LUdecomp M = Matrix([[1, 3, 3], [3, 2, 6], [3, 2, 2]]) P, L, Dee, U = M.LUdecompositionFF() assert P*M == L*Dee.inv()*U M = Matrix([[1, 2, 3, 4], [3, -1, 2, 3], [3, 1, 3, -2], [6, -1, 0, 2]]) P, L, Dee, U = M.LUdecompositionFF() assert P*M == L*Dee.inv()*U M = Matrix([[0, 0, 1], [2, 3, 0], [3, 1, 4]]) P, L, Dee, U = M.LUdecompositionFF() assert P*M == L*Dee.inv()*U # issue 15794 M = Matrix( [[1, 2, 3], [4, 5, 6], [7, 8, 9]] ) raises(ValueError, lambda : M.LUdecomposition_Simple(rankcheck=True)) def test_singular_value_decompositionD(): A = Matrix([[1, 2], [2, 1]]) U, S, V = A.singular_value_decomposition() assert U * S * V.T == A assert U.T * U == eye(U.cols) assert V.T * V == eye(V.cols) B = Matrix([[1, 2]]) U, S, V = B.singular_value_decomposition() assert U * S * V.T == B assert U.T * U == eye(U.cols) assert V.T * V == eye(V.cols) C = Matrix([ [1, 0, 0, 0, 2], [0, 0, 3, 0, 0], [0, 0, 0, 0, 0], [0, 2, 0, 0, 0], ]) U, S, V = C.singular_value_decomposition() assert U * S * V.T == C assert U.T * U == eye(U.cols) assert V.T * V == eye(V.cols) D = Matrix([[Rational(1, 3), sqrt(2)], [0, Rational(1, 4)]]) U, S, V = D.singular_value_decomposition() assert simplify(U.T * U) == eye(U.cols) assert simplify(V.T * V) == eye(V.cols) assert simplify(U * S * V.T) == D def test_QR(): A = Matrix([[1, 2], [2, 3]]) Q, S = A.QRdecomposition() R = Rational assert Q == Matrix([ [ 5**R(-1, 2), (R(2)/5)*(R(1)/5)**R(-1, 2)], [2*5**R(-1, 2), (-R(1)/5)*(R(1)/5)**R(-1, 2)]]) assert S == Matrix([[5**R(1, 2), 8*5**R(-1, 2)], [0, (R(1)/5)**R(1, 2)]]) assert Q*S == A assert Q.T * Q == eye(2) A = Matrix([[1, 1, 1], [1, 1, 3], [2, 3, 4]]) Q, R = A.QRdecomposition() assert Q.T * Q == eye(Q.cols) assert R.is_upper assert A == Q*R A = Matrix([[12, 0, -51], [6, 0, 167], [-4, 0, 24]]) Q, R = A.QRdecomposition() assert Q.T * Q == eye(Q.cols) assert R.is_upper assert A == Q*R def test_QR_non_square(): # Narrow (cols < rows) matrices A = Matrix([[9, 0, 26], [12, 0, -7], [0, 4, 4], [0, -3, -3]]) Q, R = A.QRdecomposition() assert Q.T * Q == eye(Q.cols) assert R.is_upper assert A == Q*R A = Matrix([[1, -1, 4], [1, 4, -2], [1, 4, 2], [1, -1, 0]]) Q, R = A.QRdecomposition() assert Q.T * Q == eye(Q.cols) assert R.is_upper assert A == Q*R A = Matrix(2, 1, [1, 2]) Q, R = A.QRdecomposition() assert Q.T * Q == eye(Q.cols) assert R.is_upper assert A == Q*R # Wide (cols > rows) matrices A = Matrix([[1, 2, 3], [4, 5, 6]]) Q, R = A.QRdecomposition() assert Q.T * Q == eye(Q.cols) assert R.is_upper assert A == Q*R A = Matrix([[1, 2, 3, 4], [1, 4, 9, 16], [1, 8, 27, 64]]) Q, R = A.QRdecomposition() assert Q.T * Q == eye(Q.cols) assert R.is_upper assert A == Q*R A = Matrix(1, 2, [1, 2]) Q, R = A.QRdecomposition() assert Q.T * Q == eye(Q.cols) assert R.is_upper assert A == Q*R def test_QR_trivial(): # Rank deficient matrices A = Matrix([[1, 2, 3], [4, 5, 6], [7, 8, 9]]) Q, R = A.QRdecomposition() assert Q.T * Q == eye(Q.cols) assert R.is_upper assert A == Q*R A = Matrix([[1, 1, 1], [2, 2, 2], [3, 3, 3], [4, 4, 4]]) Q, R = A.QRdecomposition() assert Q.T * Q == eye(Q.cols) assert R.is_upper assert A == Q*R A = Matrix([[1, 1, 1], [2, 2, 2], [3, 3, 3], [4, 4, 4]]).T Q, R = A.QRdecomposition() assert Q.T * Q == eye(Q.cols) assert R.is_upper assert A == Q*R # Zero rank matrices A = Matrix([[0, 0, 0]]) Q, R = A.QRdecomposition() assert Q.T * Q == eye(Q.cols) assert R.is_upper assert A == Q*R A = Matrix([[0, 0, 0]]).T Q, R = A.QRdecomposition() assert Q.T * Q == eye(Q.cols) assert R.is_upper assert A == Q*R A = Matrix([[0, 0, 0], [0, 0, 0]]) Q, R = A.QRdecomposition() assert Q.T * Q == eye(Q.cols) assert R.is_upper assert A == Q*R A = Matrix([[0, 0, 0], [0, 0, 0]]).T Q, R = A.QRdecomposition() assert Q.T * Q == eye(Q.cols) assert R.is_upper assert A == Q*R # Rank deficient matrices with zero norm from beginning columns A = Matrix([[0, 0, 0], [1, 2, 3]]).T Q, R = A.QRdecomposition() assert Q.T * Q == eye(Q.cols) assert R.is_upper assert A == Q*R A = Matrix([[0, 0, 0, 0], [1, 2, 3, 4], [0, 0, 0, 0]]).T Q, R = A.QRdecomposition() assert Q.T * Q == eye(Q.cols) assert R.is_upper assert A == Q*R A = Matrix([[0, 0, 0, 0], [1, 2, 3, 4], [0, 0, 0, 0], [2, 4, 6, 8]]).T Q, R = A.QRdecomposition() assert Q.T * Q == eye(Q.cols) assert R.is_upper assert A == Q*R A = Matrix([[0, 0, 0], [0, 0, 0], [0, 0, 0], [1, 2, 3]]).T Q, R = A.QRdecomposition() assert Q.T * Q == eye(Q.cols) assert R.is_upper assert A == Q*R def test_QR_float(): A = Matrix([[1, 1], [1, 1.01]]) Q, R = A.QRdecomposition() assert allclose(Q * R, A) assert allclose(Q * Q.T, Matrix.eye(2)) assert allclose(Q.T * Q, Matrix.eye(2)) A = Matrix([[1, 1], [1, 1.001]]) Q, R = A.QRdecomposition() assert allclose(Q * R, A) assert allclose(Q * Q.T, Matrix.eye(2)) assert allclose(Q.T * Q, Matrix.eye(2)) def test_LUdecomposition_Simple_iszerofunc(): # Test if callable passed to matrices.LUdecomposition_Simple() as iszerofunc keyword argument is used inside # matrices.LUdecomposition_Simple() magic_string = "I got passed in!" def goofyiszero(value): raise ValueError(magic_string) try: lu, p = Matrix([[1, 0], [0, 1]]).LUdecomposition_Simple(iszerofunc=goofyiszero) except ValueError as err: assert magic_string == err.args[0] return assert False def test_LUdecomposition_iszerofunc(): # Test if callable passed to matrices.LUdecomposition() as iszerofunc keyword argument is used inside # matrices.LUdecomposition_Simple() magic_string = "I got passed in!" def goofyiszero(value): raise ValueError(magic_string) try: l, u, p = Matrix([[1, 0], [0, 1]]).LUdecomposition(iszerofunc=goofyiszero) except ValueError as err: assert magic_string == err.args[0] return assert False def test_LDLdecomposition(): raises(NonSquareMatrixError, lambda: Matrix((1, 2)).LDLdecomposition()) raises(ValueError, lambda: Matrix(((1, 2), (3, 4))).LDLdecomposition()) raises(ValueError, lambda: Matrix(((5 + I, 0), (0, 1))).LDLdecomposition()) raises(ValueError, lambda: Matrix(((1, 5), (5, 1))).LDLdecomposition()) raises(ValueError, lambda: Matrix(((1, 2), (3, 4))).LDLdecomposition(hermitian=False)) A = Matrix(((1, 5), (5, 1))) L, D = A.LDLdecomposition(hermitian=False) assert L * D * L.T == A A = Matrix(((25, 15, -5), (15, 18, 0), (-5, 0, 11))) L, D = A.LDLdecomposition() assert L * D * L.T == A assert L.is_lower assert L == Matrix([[1, 0, 0], [ Rational(3, 5), 1, 0], [Rational(-1, 5), Rational(1, 3), 1]]) assert D.is_diagonal() assert D == Matrix([[25, 0, 0], [0, 9, 0], [0, 0, 9]]) A = Matrix(((4, -2*I, 2 + 2*I), (2*I, 2, -1 + I), (2 - 2*I, -1 - I, 11))) L, D = A.LDLdecomposition() assert expand_mul(L * D * L.H) == A assert L.expand() == Matrix([[1, 0, 0], [I/2, 1, 0], [S.Half - I/2, 0, 1]]) assert D.expand() == Matrix(((4, 0, 0), (0, 1, 0), (0, 0, 9))) raises(NonSquareMatrixError, lambda: SparseMatrix((1, 2)).LDLdecomposition()) raises(ValueError, lambda: SparseMatrix(((1, 2), (3, 4))).LDLdecomposition()) raises(ValueError, lambda: SparseMatrix(((5 + I, 0), (0, 1))).LDLdecomposition()) raises(ValueError, lambda: SparseMatrix(((1, 5), (5, 1))).LDLdecomposition()) raises(ValueError, lambda: SparseMatrix(((1, 2), (3, 4))).LDLdecomposition(hermitian=False)) A = SparseMatrix(((1, 5), (5, 1))) L, D = A.LDLdecomposition(hermitian=False) assert L * D * L.T == A A = SparseMatrix(((25, 15, -5), (15, 18, 0), (-5, 0, 11))) L, D = A.LDLdecomposition() assert L * D * L.T == A assert L.is_lower assert L == Matrix([[1, 0, 0], [ Rational(3, 5), 1, 0], [Rational(-1, 5), Rational(1, 3), 1]]) assert D.is_diagonal() assert D == Matrix([[25, 0, 0], [0, 9, 0], [0, 0, 9]]) A = SparseMatrix(((4, -2*I, 2 + 2*I), (2*I, 2, -1 + I), (2 - 2*I, -1 - I, 11))) L, D = A.LDLdecomposition() assert expand_mul(L * D * L.H) == A assert L == Matrix(((1, 0, 0), (I/2, 1, 0), (S.Half - I/2, 0, 1))) assert D == Matrix(((4, 0, 0), (0, 1, 0), (0, 0, 9))) def test_pinv_succeeds_with_rank_decomposition_method(): # Test rank decomposition method of pseudoinverse succeeding As = [Matrix([ [61, 89, 55, 20, 71, 0], [62, 96, 85, 85, 16, 0], [69, 56, 17, 4, 54, 0], [10, 54, 91, 41, 71, 0], [ 7, 30, 10, 48, 90, 0], [0,0,0,0,0,0]])] for A in As: A_pinv = A.pinv(method="RD") AAp = A * A_pinv ApA = A_pinv * A assert simplify(AAp * A) == A assert simplify(ApA * A_pinv) == A_pinv assert AAp.H == AAp assert ApA.H == ApA def test_rank_decomposition(): a = Matrix(0, 0, []) c, f = a.rank_decomposition() assert f.is_echelon assert c.cols == f.rows == a.rank() assert c * f == a a = Matrix(1, 1, [5]) c, f = a.rank_decomposition() assert f.is_echelon assert c.cols == f.rows == a.rank() assert c * f == a a = Matrix(3, 3, [1, 2, 3, 1, 2, 3, 1, 2, 3]) c, f = a.rank_decomposition() assert f.is_echelon assert c.cols == f.rows == a.rank() assert c * f == a a = Matrix([ [0, 0, 1, 2, 2, -5, 3], [-1, 5, 2, 2, 1, -7, 5], [0, 0, -2, -3, -3, 8, -5], [-1, 5, 0, -1, -2, 1, 0]]) c, f = a.rank_decomposition() assert f.is_echelon assert c.cols == f.rows == a.rank() assert c * f == a @slow def test_upper_hessenberg_decomposition(): A = Matrix([ [1, 0, sqrt(3)], [sqrt(2), Rational(1, 2), 2], [1, Rational(1, 4), 3], ]) H, P = A.upper_hessenberg_decomposition() assert simplify(P * P.H) == eye(P.cols) assert simplify(P.H * P) == eye(P.cols) assert H.is_upper_hessenberg assert (simplify(P * H * P.H)) == A B = Matrix([ [1, 2, 10], [8, 2, 5], [3, 12, 34], ]) H, P = B.upper_hessenberg_decomposition() assert simplify(P * P.H) == eye(P.cols) assert simplify(P.H * P) == eye(P.cols) assert H.is_upper_hessenberg assert simplify(P * H * P.H) == B C = Matrix([ [1, sqrt(2), 2, 3], [0, 5, 3, 4], [1, 1, 4, sqrt(5)], [0, 2, 2, 3] ]) H, P = C.upper_hessenberg_decomposition() assert simplify(P * P.H) == eye(P.cols) assert simplify(P.H * P) == eye(P.cols) assert H.is_upper_hessenberg assert simplify(P * H * P.H) == C D = Matrix([ [1, 2, 3], [-3, 5, 6], [4, -8, 9], ]) H, P = D.upper_hessenberg_decomposition() assert simplify(P * P.H) == eye(P.cols) assert simplify(P.H * P) == eye(P.cols) assert H.is_upper_hessenberg assert simplify(P * H * P.H) == D E = Matrix([ [1, 0, 0, 0], [0, 1, 0, 0], [1, 1, 0, 1], [1, 1, 1, 0] ]) H, P = E.upper_hessenberg_decomposition() assert simplify(P * P.H) == eye(P.cols) assert simplify(P.H * P) == eye(P.cols) assert H.is_upper_hessenberg assert simplify(P * H * P.H) == E
6ccb5e95c09400f0bfc30d74660619a738eb6951e136470b3e87fedd0483daf6
from sympy.testing.pytest import warns_deprecated_sympy from sympy import Symbol, Poly from sympy.matrices import Matrix from sympy.matrices.normalforms import invariant_factors, smith_normal_form from sympy.polys.domains import ZZ, QQ def test_smith_normal(): m = Matrix([[12,6,4,8],[3,9,6,12],[2,16,14,28],[20,10,10,20]]) smf = Matrix([[1, 0, 0, 0], [0, 10, 0, 0], [0, 0, -30, 0], [0, 0, 0, 0]]) assert smith_normal_form(m) == smf x = Symbol('x') with warns_deprecated_sympy(): m = Matrix([[Poly(x-1), Poly(1, x),Poly(-1,x)], [0, Poly(x), Poly(-1,x)], [Poly(0,x),Poly(-1,x),Poly(x)]]) invs = 1, x - 1, x**2 - 1 assert invariant_factors(m, domain=QQ[x]) == invs m = Matrix([[2, 4]]) smf = Matrix([[2, 0]]) assert smith_normal_form(m) == smf def test_smith_normal_deprecated(): from sympy.polys.solvers import RawMatrix as Matrix with warns_deprecated_sympy(): m = Matrix([[12, 6, 4,8],[3,9,6,12],[2,16,14,28],[20,10,10,20]]) setattr(m, 'ring', ZZ) with warns_deprecated_sympy(): smf = Matrix([[1, 0, 0, 0], [0, 10, 0, 0], [0, 0, -30, 0], [0, 0, 0, 0]]) assert smith_normal_form(m) == smf x = Symbol('x') with warns_deprecated_sympy(): m = Matrix([[Poly(x-1), Poly(1, x),Poly(-1,x)], [0, Poly(x), Poly(-1,x)], [Poly(0,x),Poly(-1,x),Poly(x)]]) setattr(m, 'ring', QQ[x]) invs = (Poly(1, x, domain='QQ'), Poly(x - 1, domain='QQ'), Poly(x**2 - 1, domain='QQ')) assert invariant_factors(m) == invs with warns_deprecated_sympy(): m = Matrix([[2, 4]]) setattr(m, 'ring', ZZ) with warns_deprecated_sympy(): smf = Matrix([[2, 0]]) assert smith_normal_form(m) == smf
85815ae675ee15e4d8721fe821b3fa6d6b0a3f26afaaeb04a30f71967aa6b1c3
import random import concurrent.futures from collections.abc import Hashable from sympy import ( Abs, Add, E, Float, I, Integer, Max, Min, Poly, Pow, PurePoly, Rational, S, Symbol, cos, exp, log, oo, pi, signsimp, simplify, sin, sqrt, symbols, sympify, trigsimp, tan, sstr, diff, Function, expand, FiniteSet) from sympy.matrices.matrices import (ShapeError, MatrixError, NonSquareMatrixError, DeferredVector, _find_reasonable_pivot_naive, _simplify) from sympy.matrices import ( GramSchmidt, ImmutableMatrix, ImmutableSparseMatrix, Matrix, SparseMatrix, casoratian, diag, eye, hessian, matrix_multiply_elementwise, ones, randMatrix, rot_axis1, rot_axis2, rot_axis3, wronskian, zeros, MutableDenseMatrix, ImmutableDenseMatrix, MatrixSymbol, dotprodsimp) from sympy.matrices.utilities import _dotprodsimp_state from sympy.core.compatibility import iterable from sympy.core import Tuple, Wild from sympy.functions.special.tensor_functions import KroneckerDelta from sympy.utilities.iterables import flatten, capture from sympy.testing.pytest import raises, XFAIL, slow, skip, warns_deprecated_sympy from sympy.assumptions import Q from sympy.tensor.array import Array from sympy.matrices.expressions import MatPow from sympy.abc import a, b, c, d, x, y, z, t # don't re-order this list classes = (Matrix, SparseMatrix, ImmutableMatrix, ImmutableSparseMatrix) def test_args(): for n, cls in enumerate(classes): m = cls.zeros(3, 2) # all should give back the same type of arguments, e.g. ints for shape assert m.shape == (3, 2) and all(type(i) is int for i in m.shape) assert m.rows == 3 and type(m.rows) is int assert m.cols == 2 and type(m.cols) is int if not n % 2: assert type(m._mat) in (list, tuple, Tuple) else: assert type(m._smat) is dict def test_division(): v = Matrix(1, 2, [x, y]) assert v/z == Matrix(1, 2, [x/z, y/z]) def test_sum(): m = Matrix([[1, 2, 3], [x, y, x], [2*y, -50, z*x]]) assert m + m == Matrix([[2, 4, 6], [2*x, 2*y, 2*x], [4*y, -100, 2*z*x]]) n = Matrix(1, 2, [1, 2]) raises(ShapeError, lambda: m + n) def test_abs(): m = Matrix(1, 2, [-3, x]) n = Matrix(1, 2, [3, Abs(x)]) assert abs(m) == n def test_addition(): a = Matrix(( (1, 2), (3, 1), )) b = Matrix(( (1, 2), (3, 0), )) assert a + b == a.add(b) == Matrix([[2, 4], [6, 1]]) def test_fancy_index_matrix(): for M in (Matrix, SparseMatrix): a = M(3, 3, range(9)) assert a == a[:, :] assert a[1, :] == Matrix(1, 3, [3, 4, 5]) assert a[:, 1] == Matrix([1, 4, 7]) assert a[[0, 1], :] == Matrix([[0, 1, 2], [3, 4, 5]]) assert a[[0, 1], 2] == a[[0, 1], [2]] assert a[2, [0, 1]] == a[[2], [0, 1]] assert a[:, [0, 1]] == Matrix([[0, 1], [3, 4], [6, 7]]) assert a[0, 0] == 0 assert a[0:2, :] == Matrix([[0, 1, 2], [3, 4, 5]]) assert a[:, 0:2] == Matrix([[0, 1], [3, 4], [6, 7]]) assert a[::2, 1] == a[[0, 2], 1] assert a[1, ::2] == a[1, [0, 2]] a = M(3, 3, range(9)) assert a[[0, 2, 1, 2, 1], :] == Matrix([ [0, 1, 2], [6, 7, 8], [3, 4, 5], [6, 7, 8], [3, 4, 5]]) assert a[:, [0,2,1,2,1]] == Matrix([ [0, 2, 1, 2, 1], [3, 5, 4, 5, 4], [6, 8, 7, 8, 7]]) a = SparseMatrix.zeros(3) a[1, 2] = 2 a[0, 1] = 3 a[2, 0] = 4 assert a.extract([1, 1], [2]) == Matrix([ [2], [2]]) assert a.extract([1, 0], [2, 2, 2]) == Matrix([ [2, 2, 2], [0, 0, 0]]) assert a.extract([1, 0, 1, 2], [2, 0, 1, 0]) == Matrix([ [2, 0, 0, 0], [0, 0, 3, 0], [2, 0, 0, 0], [0, 4, 0, 4]]) def test_multiplication(): a = Matrix(( (1, 2), (3, 1), (0, 6), )) b = Matrix(( (1, 2), (3, 0), )) c = a*b assert c[0, 0] == 7 assert c[0, 1] == 2 assert c[1, 0] == 6 assert c[1, 1] == 6 assert c[2, 0] == 18 assert c[2, 1] == 0 try: eval('c = a @ b') except SyntaxError: pass else: assert c[0, 0] == 7 assert c[0, 1] == 2 assert c[1, 0] == 6 assert c[1, 1] == 6 assert c[2, 0] == 18 assert c[2, 1] == 0 h = matrix_multiply_elementwise(a, c) assert h == a.multiply_elementwise(c) assert h[0, 0] == 7 assert h[0, 1] == 4 assert h[1, 0] == 18 assert h[1, 1] == 6 assert h[2, 0] == 0 assert h[2, 1] == 0 raises(ShapeError, lambda: matrix_multiply_elementwise(a, b)) c = b * Symbol("x") assert isinstance(c, Matrix) assert c[0, 0] == x assert c[0, 1] == 2*x assert c[1, 0] == 3*x assert c[1, 1] == 0 c2 = x * b assert c == c2 c = 5 * b assert isinstance(c, Matrix) assert c[0, 0] == 5 assert c[0, 1] == 2*5 assert c[1, 0] == 3*5 assert c[1, 1] == 0 try: eval('c = 5 @ b') except SyntaxError: pass else: assert isinstance(c, Matrix) assert c[0, 0] == 5 assert c[0, 1] == 2*5 assert c[1, 0] == 3*5 assert c[1, 1] == 0 def test_power(): raises(NonSquareMatrixError, lambda: Matrix((1, 2))**2) R = Rational A = Matrix([[2, 3], [4, 5]]) assert (A**-3)[:] == [R(-269)/8, R(153)/8, R(51)/2, R(-29)/2] assert (A**5)[:] == [6140, 8097, 10796, 14237] A = Matrix([[2, 1, 3], [4, 2, 4], [6, 12, 1]]) assert (A**3)[:] == [290, 262, 251, 448, 440, 368, 702, 954, 433] assert A**0 == eye(3) assert A**1 == A assert (Matrix([[2]]) ** 100)[0, 0] == 2**100 assert eye(2)**10000000 == eye(2) assert Matrix([[1, 2], [3, 4]])**Integer(2) == Matrix([[7, 10], [15, 22]]) A = Matrix([[33, 24], [48, 57]]) assert (A**S.Half)[:] == [5, 2, 4, 7] A = Matrix([[0, 4], [-1, 5]]) assert (A**S.Half)**2 == A assert Matrix([[1, 0], [1, 1]])**S.Half == Matrix([[1, 0], [S.Half, 1]]) assert Matrix([[1, 0], [1, 1]])**0.5 == Matrix([[1.0, 0], [0.5, 1.0]]) from sympy.abc import a, b, n assert Matrix([[1, a], [0, 1]])**n == Matrix([[1, a*n], [0, 1]]) assert Matrix([[b, a], [0, b]])**n == Matrix([[b**n, a*b**(n-1)*n], [0, b**n]]) assert Matrix([ [a**n, a**(n - 1)*n, (a**n*n**2 - a**n*n)/(2*a**2)], [ 0, a**n, a**(n - 1)*n], [ 0, 0, a**n]]) assert Matrix([[a, 1, 0], [0, a, 0], [0, 0, b]])**n == Matrix([ [a**n, a**(n-1)*n, 0], [0, a**n, 0], [0, 0, b**n]]) A = Matrix([[1, 0], [1, 7]]) assert A._matrix_pow_by_jordan_blocks(S(3)) == A._eval_pow_by_recursion(3) A = Matrix([[2]]) assert A**10 == Matrix([[2**10]]) == A._matrix_pow_by_jordan_blocks(S(10)) == \ A._eval_pow_by_recursion(10) # testing a matrix that cannot be jordan blocked issue 11766 m = Matrix([[3, 0, 0, 0, -3], [0, -3, -3, 0, 3], [0, 3, 0, 3, 0], [0, 0, 3, 0, 3], [3, 0, 0, 3, 0]]) raises(MatrixError, lambda: m._matrix_pow_by_jordan_blocks(S(10))) # test issue 11964 raises(MatrixError, lambda: Matrix([[1, 1], [3, 3]])._matrix_pow_by_jordan_blocks(S(-10))) A = Matrix([[0, 1, 0], [0, 0, 1], [0, 0, 0]]) # Nilpotent jordan block size 3 assert A**10.0 == Matrix([[0, 0, 0], [0, 0, 0], [0, 0, 0]]) raises(ValueError, lambda: A**2.1) raises(ValueError, lambda: A**Rational(3, 2)) A = Matrix([[8, 1], [3, 2]]) assert A**10.0 == Matrix([[1760744107, 272388050], [817164150, 126415807]]) A = Matrix([[0, 0, 1], [0, 0, 1], [0, 0, 1]]) # Nilpotent jordan block size 1 assert A**10.0 == Matrix([[0, 0, 1], [0, 0, 1], [0, 0, 1]]) A = Matrix([[0, 1, 0], [0, 0, 1], [0, 0, 1]]) # Nilpotent jordan block size 2 assert A**10.0 == Matrix([[0, 0, 1], [0, 0, 1], [0, 0, 1]]) n = Symbol('n', integer=True) assert isinstance(A**n, MatPow) n = Symbol('n', integer=True, negative=True) raises(ValueError, lambda: A**n) n = Symbol('n', integer=True, nonnegative=True) assert A**n == Matrix([ [KroneckerDelta(0, n), KroneckerDelta(1, n), -KroneckerDelta(0, n) - KroneckerDelta(1, n) + 1], [ 0, KroneckerDelta(0, n), 1 - KroneckerDelta(0, n)], [ 0, 0, 1]]) assert A**(n + 2) == Matrix([[0, 0, 1], [0, 0, 1], [0, 0, 1]]) raises(ValueError, lambda: A**Rational(3, 2)) A = Matrix([[0, 0, 1], [3, 0, 1], [4, 3, 1]]) assert A**5.0 == Matrix([[168, 72, 89], [291, 144, 161], [572, 267, 329]]) assert A**5.0 == A**5 A = Matrix([[0, 1, 0],[-1, 0, 0],[0, 0, 0]]) n = Symbol("n") An = A**n assert An.subs(n, 2).doit() == A**2 raises(ValueError, lambda: An.subs(n, -2).doit()) assert An * An == A**(2*n) # concretizing behavior for non-integer and complex powers A = Matrix([[0,0,0],[0,0,0],[0,0,0]]) n = Symbol('n', integer=True, positive=True) assert A**n == A n = Symbol('n', integer=True, nonnegative=True) assert A**n == diag(0**n, 0**n, 0**n) assert (A**n).subs(n, 0) == eye(3) assert (A**n).subs(n, 1) == zeros(3) A = Matrix ([[2,0,0],[0,2,0],[0,0,2]]) assert A**2.1 == diag (2**2.1, 2**2.1, 2**2.1) assert A**I == diag (2**I, 2**I, 2**I) A = Matrix([[0, 1, 0], [0, 0, 1], [0, 0, 1]]) raises(ValueError, lambda: A**2.1) raises(ValueError, lambda: A**I) A = Matrix([[S.Half, S.Half], [S.Half, S.Half]]) assert A**S.Half == A A = Matrix([[1, 1],[3, 3]]) assert A**S.Half == Matrix ([[S.Half, S.Half], [3*S.Half, 3*S.Half]]) def test_issue_17247_expression_blowup_1(): M = Matrix([[1+x, 1-x], [1-x, 1+x]]) with dotprodsimp(True): assert M.exp().expand() == Matrix([ [ (exp(2*x) + exp(2))/2, (-exp(2*x) + exp(2))/2], [(-exp(2*x) + exp(2))/2, (exp(2*x) + exp(2))/2]]) def test_issue_17247_expression_blowup_2(): M = Matrix([[1+x, 1-x], [1-x, 1+x]]) with dotprodsimp(True): P, J = M.jordan_form () assert P*J*P.inv() def test_issue_17247_expression_blowup_3(): M = Matrix([[1+x, 1-x], [1-x, 1+x]]) with dotprodsimp(True): assert M**100 == Matrix([ [633825300114114700748351602688*x**100 + 633825300114114700748351602688, 633825300114114700748351602688 - 633825300114114700748351602688*x**100], [633825300114114700748351602688 - 633825300114114700748351602688*x**100, 633825300114114700748351602688*x**100 + 633825300114114700748351602688]]) def test_issue_17247_expression_blowup_4(): # This matrix takes extremely long on current master even with intermediate simplification so an abbreviated version is used. It is left here for test in case of future optimizations. # M = Matrix(S('''[ # [ -3/4, 45/32 - 37*I/16, 1/4 + I/2, -129/64 - 9*I/64, 1/4 - 5*I/16, 65/128 + 87*I/64, -9/32 - I/16, 183/256 - 97*I/128, 3/64 + 13*I/64, -23/32 - 59*I/256, 15/128 - 3*I/32, 19/256 + 551*I/1024], # [-149/64 + 49*I/32, -177/128 - 1369*I/128, 125/64 + 87*I/64, -2063/256 + 541*I/128, 85/256 - 33*I/16, 805/128 + 2415*I/512, -219/128 + 115*I/256, 6301/4096 - 6609*I/1024, 119/128 + 143*I/128, -10879/2048 + 4343*I/4096, 129/256 - 549*I/512, 42533/16384 + 29103*I/8192], # [ 1/2 - I, 9/4 + 55*I/16, -3/4, 45/32 - 37*I/16, 1/4 + I/2, -129/64 - 9*I/64, 1/4 - 5*I/16, 65/128 + 87*I/64, -9/32 - I/16, 183/256 - 97*I/128, 3/64 + 13*I/64, -23/32 - 59*I/256], # [ -5/8 - 39*I/16, 2473/256 + 137*I/64, -149/64 + 49*I/32, -177/128 - 1369*I/128, 125/64 + 87*I/64, -2063/256 + 541*I/128, 85/256 - 33*I/16, 805/128 + 2415*I/512, -219/128 + 115*I/256, 6301/4096 - 6609*I/1024, 119/128 + 143*I/128, -10879/2048 + 4343*I/4096], # [ 1 + I, -19/4 + 5*I/4, 1/2 - I, 9/4 + 55*I/16, -3/4, 45/32 - 37*I/16, 1/4 + I/2, -129/64 - 9*I/64, 1/4 - 5*I/16, 65/128 + 87*I/64, -9/32 - I/16, 183/256 - 97*I/128], # [ 21/8 + I, -537/64 + 143*I/16, -5/8 - 39*I/16, 2473/256 + 137*I/64, -149/64 + 49*I/32, -177/128 - 1369*I/128, 125/64 + 87*I/64, -2063/256 + 541*I/128, 85/256 - 33*I/16, 805/128 + 2415*I/512, -219/128 + 115*I/256, 6301/4096 - 6609*I/1024], # [ -2, 17/4 - 13*I/2, 1 + I, -19/4 + 5*I/4, 1/2 - I, 9/4 + 55*I/16, -3/4, 45/32 - 37*I/16, 1/4 + I/2, -129/64 - 9*I/64, 1/4 - 5*I/16, 65/128 + 87*I/64], # [ 1/4 + 13*I/4, -825/64 - 147*I/32, 21/8 + I, -537/64 + 143*I/16, -5/8 - 39*I/16, 2473/256 + 137*I/64, -149/64 + 49*I/32, -177/128 - 1369*I/128, 125/64 + 87*I/64, -2063/256 + 541*I/128, 85/256 - 33*I/16, 805/128 + 2415*I/512], # [ -4*I, 27/2 + 6*I, -2, 17/4 - 13*I/2, 1 + I, -19/4 + 5*I/4, 1/2 - I, 9/4 + 55*I/16, -3/4, 45/32 - 37*I/16, 1/4 + I/2, -129/64 - 9*I/64], # [ 1/4 + 5*I/2, -23/8 - 57*I/16, 1/4 + 13*I/4, -825/64 - 147*I/32, 21/8 + I, -537/64 + 143*I/16, -5/8 - 39*I/16, 2473/256 + 137*I/64, -149/64 + 49*I/32, -177/128 - 1369*I/128, 125/64 + 87*I/64, -2063/256 + 541*I/128], # [ -4, 9 - 5*I, -4*I, 27/2 + 6*I, -2, 17/4 - 13*I/2, 1 + I, -19/4 + 5*I/4, 1/2 - I, 9/4 + 55*I/16, -3/4, 45/32 - 37*I/16], # [ -2*I, 119/8 + 29*I/4, 1/4 + 5*I/2, -23/8 - 57*I/16, 1/4 + 13*I/4, -825/64 - 147*I/32, 21/8 + I, -537/64 + 143*I/16, -5/8 - 39*I/16, 2473/256 + 137*I/64, -149/64 + 49*I/32, -177/128 - 1369*I/128]]''')) # assert M**10 == Matrix([ # [ 7*(-221393644768594642173548179825793834595 - 1861633166167425978847110897013541127952*I)/9671406556917033397649408, 15*(31670992489131684885307005100073928751695 + 10329090958303458811115024718207404523808*I)/77371252455336267181195264, 7*(-3710978679372178839237291049477017392703 + 1377706064483132637295566581525806894169*I)/19342813113834066795298816, (9727707023582419994616144751727760051598 - 59261571067013123836477348473611225724433*I)/9671406556917033397649408, (31896723509506857062605551443641668183707 + 54643444538699269118869436271152084599580*I)/38685626227668133590597632, (-2024044860947539028275487595741003997397402 + 130959428791783397562960461903698670485863*I)/309485009821345068724781056, 3*(26190251453797590396533756519358368860907 - 27221191754180839338002754608545400941638*I)/77371252455336267181195264, (1154643595139959842768960128434994698330461 + 3385496216250226964322872072260446072295634*I)/618970019642690137449562112, 3*(-31849347263064464698310044805285774295286 - 11877437776464148281991240541742691164309*I)/77371252455336267181195264, (4661330392283532534549306589669150228040221 - 4171259766019818631067810706563064103956871*I)/1237940039285380274899124224, (9598353794289061833850770474812760144506 + 358027153990999990968244906482319780943983*I)/309485009821345068724781056, (-9755135335127734571547571921702373498554177 - 4837981372692695195747379349593041939686540*I)/2475880078570760549798248448], # [(-379516731607474268954110071392894274962069 - 422272153179747548473724096872271700878296*I)/77371252455336267181195264, (41324748029613152354787280677832014263339501 - 12715121258662668420833935373453570749288074*I)/1237940039285380274899124224, (-339216903907423793947110742819264306542397 + 494174755147303922029979279454787373566517*I)/77371252455336267181195264, (-18121350839962855576667529908850640619878381 - 37413012454129786092962531597292531089199003*I)/1237940039285380274899124224, (2489661087330511608618880408199633556675926 + 1137821536550153872137379935240732287260863*I)/309485009821345068724781056, (-136644109701594123227587016790354220062972119 + 110130123468183660555391413889600443583585272*I)/4951760157141521099596496896, (1488043981274920070468141664150073426459593 - 9691968079933445130866371609614474474327650*I)/1237940039285380274899124224, 27*(4636797403026872518131756991410164760195942 + 3369103221138229204457272860484005850416533*I)/4951760157141521099596496896, (-8534279107365915284081669381642269800472363 + 2241118846262661434336333368511372725482742*I)/1237940039285380274899124224, (60923350128174260992536531692058086830950875 - 263673488093551053385865699805250505661590126*I)/9903520314283042199192993792, (18520943561240714459282253753348921824172569 + 24846649186468656345966986622110971925703604*I)/4951760157141521099596496896, (-232781130692604829085973604213529649638644431 + 35981505277760667933017117949103953338570617*I)/9903520314283042199192993792], # [ (8742968295129404279528270438201520488950 + 3061473358639249112126847237482570858327*I)/4835703278458516698824704, (-245657313712011778432792959787098074935273 + 253113767861878869678042729088355086740856*I)/38685626227668133590597632, (1947031161734702327107371192008011621193 - 19462330079296259148177542369999791122762*I)/9671406556917033397649408, (552856485625209001527688949522750288619217 + 392928441196156725372494335248099016686580*I)/77371252455336267181195264, (-44542866621905323121630214897126343414629 + 3265340021421335059323962377647649632959*I)/19342813113834066795298816, (136272594005759723105646069956434264218730 - 330975364731707309489523680957584684763587*I)/38685626227668133590597632, (27392593965554149283318732469825168894401 + 75157071243800133880129376047131061115278*I)/38685626227668133590597632, 7*(-357821652913266734749960136017214096276154 - 45509144466378076475315751988405961498243*I)/309485009821345068724781056, (104485001373574280824835174390219397141149 - 99041000529599568255829489765415726168162*I)/77371252455336267181195264, (1198066993119982409323525798509037696321291 + 4249784165667887866939369628840569844519936*I)/618970019642690137449562112, (-114985392587849953209115599084503853611014 - 52510376847189529234864487459476242883449*I)/77371252455336267181195264, (6094620517051332877965959223269600650951573 - 4683469779240530439185019982269137976201163*I)/1237940039285380274899124224], # [ (611292255597977285752123848828590587708323 - 216821743518546668382662964473055912169502*I)/77371252455336267181195264, (-1144023204575811464652692396337616594307487 + 12295317806312398617498029126807758490062855*I)/309485009821345068724781056, (-374093027769390002505693378578475235158281 - 573533923565898290299607461660384634333639*I)/77371252455336267181195264, (47405570632186659000138546955372796986832987 - 2837476058950808941605000274055970055096534*I)/1237940039285380274899124224, (-571573207393621076306216726219753090535121 + 533381457185823100878764749236639320783831*I)/77371252455336267181195264, (-7096548151856165056213543560958582513797519 - 24035731898756040059329175131592138642195366*I)/618970019642690137449562112, (2396762128833271142000266170154694033849225 + 1448501087375679588770230529017516492953051*I)/309485009821345068724781056, (-150609293845161968447166237242456473262037053 + 92581148080922977153207018003184520294188436*I)/4951760157141521099596496896, 5*(270278244730804315149356082977618054486347 - 1997830155222496880429743815321662710091562*I)/1237940039285380274899124224, (62978424789588828258068912690172109324360330 + 44803641177219298311493356929537007630129097*I)/2475880078570760549798248448, 19*(-451431106327656743945775812536216598712236 + 114924966793632084379437683991151177407937*I)/1237940039285380274899124224, (63417747628891221594106738815256002143915995 - 261508229397507037136324178612212080871150958*I)/9903520314283042199192993792], # [ (-2144231934021288786200752920446633703357 + 2305614436009705803670842248131563850246*I)/1208925819614629174706176, (-90720949337459896266067589013987007078153 - 221951119475096403601562347412753844534569*I)/19342813113834066795298816, (11590973613116630788176337262688659880376 + 6514520676308992726483494976339330626159*I)/4835703278458516698824704, 3*(-131776217149000326618649542018343107657237 + 79095042939612668486212006406818285287004*I)/38685626227668133590597632, (10100577916793945997239221374025741184951 - 28631383488085522003281589065994018550748*I)/9671406556917033397649408, 67*(10090295594251078955008130473573667572549 + 10449901522697161049513326446427839676762*I)/77371252455336267181195264, (-54270981296988368730689531355811033930513 - 3413683117592637309471893510944045467443*I)/19342813113834066795298816, (440372322928679910536575560069973699181278 - 736603803202303189048085196176918214409081*I)/77371252455336267181195264, (33220374714789391132887731139763250155295 + 92055083048787219934030779066298919603554*I)/38685626227668133590597632, 5*(-594638554579967244348856981610805281527116 - 82309245323128933521987392165716076704057*I)/309485009821345068724781056, (128056368815300084550013708313312073721955 - 114619107488668120303579745393765245911404*I)/77371252455336267181195264, 21*(59839959255173222962789517794121843393573 + 241507883613676387255359616163487405826334*I)/618970019642690137449562112], # [ (-13454485022325376674626653802541391955147 + 184471402121905621396582628515905949793486*I)/19342813113834066795298816, (-6158730123400322562149780662133074862437105 - 3416173052604643794120262081623703514107476*I)/154742504910672534362390528, (770558003844914708453618983120686116100419 - 127758381209767638635199674005029818518766*I)/77371252455336267181195264, (-4693005771813492267479835161596671660631703 + 12703585094750991389845384539501921531449948*I)/309485009821345068724781056, (-295028157441149027913545676461260860036601 - 841544569970643160358138082317324743450770*I)/77371252455336267181195264, (56716442796929448856312202561538574275502893 + 7216818824772560379753073185990186711454778*I)/1237940039285380274899124224, 15*(-87061038932753366532685677510172566368387 + 61306141156647596310941396434445461895538*I)/154742504910672534362390528, (-3455315109680781412178133042301025723909347 - 24969329563196972466388460746447646686670670*I)/618970019642690137449562112, (2453418854160886481106557323699250865361849 + 1497886802326243014471854112161398141242514*I)/309485009821345068724781056, (-151343224544252091980004429001205664193082173 + 90471883264187337053549090899816228846836628*I)/4951760157141521099596496896, (1652018205533026103358164026239417416432989 - 9959733619236515024261775397109724431400162*I)/1237940039285380274899124224, 3*(40676374242956907656984876692623172736522006 + 31023357083037817469535762230872667581366205*I)/4951760157141521099596496896], # [ (-1226990509403328460274658603410696548387 - 4131739423109992672186585941938392788458*I)/1208925819614629174706176, (162392818524418973411975140074368079662703 + 23706194236915374831230612374344230400704*I)/9671406556917033397649408, (-3935678233089814180000602553655565621193 + 2283744757287145199688061892165659502483*I)/1208925819614629174706176, (-2400210250844254483454290806930306285131 - 315571356806370996069052930302295432758205*I)/19342813113834066795298816, (13365917938215281056563183751673390817910 + 15911483133819801118348625831132324863881*I)/4835703278458516698824704, 3*(-215950551370668982657516660700301003897855 + 51684341999223632631602864028309400489378*I)/38685626227668133590597632, (20886089946811765149439844691320027184765 - 30806277083146786592790625980769214361844*I)/9671406556917033397649408, (562180634592713285745940856221105667874855 + 1031543963988260765153550559766662245114916*I)/77371252455336267181195264, (-65820625814810177122941758625652476012867 - 12429918324787060890804395323920477537595*I)/19342813113834066795298816, (319147848192012911298771180196635859221089 - 402403304933906769233365689834404519960394*I)/38685626227668133590597632, (23035615120921026080284733394359587955057 + 115351677687031786114651452775242461310624*I)/38685626227668133590597632, (-3426830634881892756966440108592579264936130 - 1022954961164128745603407283836365128598559*I)/309485009821345068724781056], # [ (-192574788060137531023716449082856117537757 - 69222967328876859586831013062387845780692*I)/19342813113834066795298816, (2736383768828013152914815341491629299773262 - 2773252698016291897599353862072533475408743*I)/77371252455336267181195264, (-23280005281223837717773057436155921656805 + 214784953368021840006305033048142888879224*I)/19342813113834066795298816, (-3035247484028969580570400133318947903462326 - 2195168903335435855621328554626336958674325*I)/77371252455336267181195264, (984552428291526892214541708637840971548653 - 64006622534521425620714598573494988589378*I)/77371252455336267181195264, (-3070650452470333005276715136041262898509903 + 7286424705750810474140953092161794621989080*I)/154742504910672534362390528, (-147848877109756404594659513386972921139270 - 416306113044186424749331418059456047650861*I)/38685626227668133590597632, (55272118474097814260289392337160619494260781 + 7494019668394781211907115583302403519488058*I)/1237940039285380274899124224, (-581537886583682322424771088996959213068864 + 542191617758465339135308203815256798407429*I)/77371252455336267181195264, (-6422548983676355789975736799494791970390991 - 23524183982209004826464749309156698827737702*I)/618970019642690137449562112, 7*(180747195387024536886923192475064903482083 + 84352527693562434817771649853047924991804*I)/154742504910672534362390528, (-135485179036717001055310712747643466592387031 + 102346575226653028836678855697782273460527608*I)/4951760157141521099596496896], # [ (3384238362616083147067025892852431152105 + 156724444932584900214919898954874618256*I)/604462909807314587353088, (-59558300950677430189587207338385764871866 + 114427143574375271097298201388331237478857*I)/4835703278458516698824704, (-1356835789870635633517710130971800616227 - 7023484098542340388800213478357340875410*I)/1208925819614629174706176, (234884918567993750975181728413524549575881 + 79757294640629983786895695752733890213506*I)/9671406556917033397649408, (-7632732774935120473359202657160313866419 + 2905452608512927560554702228553291839465*I)/1208925819614629174706176, (52291747908702842344842889809762246649489 - 520996778817151392090736149644507525892649*I)/19342813113834066795298816, (17472406829219127839967951180375981717322 + 23464704213841582137898905375041819568669*I)/4835703278458516698824704, (-911026971811893092350229536132730760943307 + 150799318130900944080399439626714846752360*I)/38685626227668133590597632, (26234457233977042811089020440646443590687 - 45650293039576452023692126463683727692890*I)/9671406556917033397649408, 3*(288348388717468992528382586652654351121357 + 454526517721403048270274049572136109264668*I)/77371252455336267181195264, (-91583492367747094223295011999405657956347 - 12704691128268298435362255538069612411331*I)/19342813113834066795298816, (411208730251327843849027957710164064354221 - 569898526380691606955496789378230959965898*I)/38685626227668133590597632], # [ (27127513117071487872628354831658811211795 - 37765296987901990355760582016892124833857*I)/4835703278458516698824704, (1741779916057680444272938534338833170625435 + 3083041729779495966997526404685535449810378*I)/77371252455336267181195264, 3*(-60642236251815783728374561836962709533401 - 24630301165439580049891518846174101510744*I)/19342813113834066795298816, 3*(445885207364591681637745678755008757483408 - 350948497734812895032502179455610024541643*I)/38685626227668133590597632, (-47373295621391195484367368282471381775684 + 219122969294089357477027867028071400054973*I)/19342813113834066795298816, (-2801565819673198722993348253876353741520438 - 2250142129822658548391697042460298703335701*I)/77371252455336267181195264, (801448252275607253266997552356128790317119 - 50890367688077858227059515894356594900558*I)/77371252455336267181195264, (-5082187758525931944557763799137987573501207 + 11610432359082071866576699236013484487676124*I)/309485009821345068724781056, (-328925127096560623794883760398247685166830 - 643447969697471610060622160899409680422019*I)/77371252455336267181195264, 15*(2954944669454003684028194956846659916299765 + 33434406416888505837444969347824812608566*I)/1237940039285380274899124224, (-415749104352001509942256567958449835766827 + 479330966144175743357171151440020955412219*I)/77371252455336267181195264, 3*(-4639987285852134369449873547637372282914255 - 11994411888966030153196659207284951579243273*I)/1237940039285380274899124224], # [ (-478846096206269117345024348666145495601 + 1249092488629201351470551186322814883283*I)/302231454903657293676544, (-17749319421930878799354766626365926894989 - 18264580106418628161818752318217357231971*I)/1208925819614629174706176, (2801110795431528876849623279389579072819 + 363258850073786330770713557775566973248*I)/604462909807314587353088, (-59053496693129013745775512127095650616252 + 78143588734197260279248498898321500167517*I)/4835703278458516698824704, (-283186724922498212468162690097101115349 - 6443437753863179883794497936345437398276*I)/1208925819614629174706176, (188799118826748909206887165661384998787543 + 84274736720556630026311383931055307398820*I)/9671406556917033397649408, (-5482217151670072904078758141270295025989 + 1818284338672191024475557065444481298568*I)/1208925819614629174706176, (56564463395350195513805521309731217952281 - 360208541416798112109946262159695452898431*I)/19342813113834066795298816, 11*(1259539805728870739006416869463689438068 + 1409136581547898074455004171305324917387*I)/4835703278458516698824704, 5*(-123701190701414554945251071190688818343325 + 30997157322590424677294553832111902279712*I)/38685626227668133590597632, (16130917381301373033736295883982414239781 - 32752041297570919727145380131926943374516*I)/9671406556917033397649408, (650301385108223834347093740500375498354925 + 899526407681131828596801223402866051809258*I)/77371252455336267181195264], # [ (9011388245256140876590294262420614839483 + 8167917972423946282513000869327525382672*I)/1208925819614629174706176, (-426393174084720190126376382194036323028924 + 180692224825757525982858693158209545430621*I)/9671406556917033397649408, (24588556702197802674765733448108154175535 - 45091766022876486566421953254051868331066*I)/4835703278458516698824704, (1872113939365285277373877183750416985089691 + 3030392393733212574744122057679633775773130*I)/77371252455336267181195264, (-222173405538046189185754954524429864167549 - 75193157893478637039381059488387511299116*I)/19342813113834066795298816, (2670821320766222522963689317316937579844558 - 2645837121493554383087981511645435472169191*I)/77371252455336267181195264, 5*(-2100110309556476773796963197283876204940 + 41957457246479840487980315496957337371937*I)/19342813113834066795298816, (-5733743755499084165382383818991531258980593 - 3328949988392698205198574824396695027195732*I)/154742504910672534362390528, (707827994365259025461378911159398206329247 - 265730616623227695108042528694302299777294*I)/77371252455336267181195264, (-1442501604682933002895864804409322823788319 + 11504137805563265043376405214378288793343879*I)/309485009821345068724781056, (-56130472299445561499538726459719629522285 - 61117552419727805035810982426639329818864*I)/9671406556917033397649408, (39053692321126079849054272431599539429908717 - 10209127700342570953247177602860848130710666*I)/1237940039285380274899124224]]) M = Matrix(S('''[ [ -3/4, 45/32 - 37*I/16, 1/4 + I/2, -129/64 - 9*I/64, 1/4 - 5*I/16, 65/128 + 87*I/64], [-149/64 + 49*I/32, -177/128 - 1369*I/128, 125/64 + 87*I/64, -2063/256 + 541*I/128, 85/256 - 33*I/16, 805/128 + 2415*I/512], [ 1/2 - I, 9/4 + 55*I/16, -3/4, 45/32 - 37*I/16, 1/4 + I/2, -129/64 - 9*I/64], [ -5/8 - 39*I/16, 2473/256 + 137*I/64, -149/64 + 49*I/32, -177/128 - 1369*I/128, 125/64 + 87*I/64, -2063/256 + 541*I/128], [ 1 + I, -19/4 + 5*I/4, 1/2 - I, 9/4 + 55*I/16, -3/4, 45/32 - 37*I/16], [ 21/8 + I, -537/64 + 143*I/16, -5/8 - 39*I/16, 2473/256 + 137*I/64, -149/64 + 49*I/32, -177/128 - 1369*I/128]]''')) with dotprodsimp(True): assert M**10 == Matrix(S('''[ [ 7369525394972778926719607798014571861/604462909807314587353088 - 229284202061790301477392339912557559*I/151115727451828646838272, -19704281515163975949388435612632058035/1208925819614629174706176 + 14319858347987648723768698170712102887*I/302231454903657293676544, -3623281909451783042932142262164941211/604462909807314587353088 - 6039240602494288615094338643452320495*I/604462909807314587353088, 109260497799140408739847239685705357695/2417851639229258349412352 - 7427566006564572463236368211555511431*I/2417851639229258349412352, -16095803767674394244695716092817006641/2417851639229258349412352 + 10336681897356760057393429626719177583*I/1208925819614629174706176, -42207883340488041844332828574359769743/2417851639229258349412352 - 182332262671671273188016400290188468499*I/4835703278458516698824704], [50566491050825573392726324995779608259/1208925819614629174706176 - 90047007594468146222002432884052362145*I/2417851639229258349412352, 74273703462900000967697427843983822011/1208925819614629174706176 + 265947522682943571171988741842776095421*I/1208925819614629174706176, -116900341394390200556829767923360888429/2417851639229258349412352 - 53153263356679268823910621474478756845*I/2417851639229258349412352, 195407378023867871243426523048612490249/1208925819614629174706176 - 1242417915995360200584837585002906728929*I/9671406556917033397649408, -863597594389821970177319682495878193/302231454903657293676544 + 476936100741548328800725360758734300481*I/9671406556917033397649408, -3154451590535653853562472176601754835575/19342813113834066795298816 - 232909875490506237386836489998407329215*I/2417851639229258349412352], [ -1715444997702484578716037230949868543/302231454903657293676544 + 5009695651321306866158517287924120777*I/302231454903657293676544, -30551582497996879620371947949342101301/604462909807314587353088 - 7632518367986526187139161303331519629*I/151115727451828646838272, 312680739924495153190604170938220575/18889465931478580854784 - 108664334509328818765959789219208459*I/75557863725914323419136, -14693696966703036206178521686918865509/604462909807314587353088 + 72345386220900843930147151999899692401*I/1208925819614629174706176, -8218872496728882299722894680635296519/1208925819614629174706176 - 16776782833358893712645864791807664983*I/1208925819614629174706176, 143237839169380078671242929143670635137/2417851639229258349412352 + 2883817094806115974748882735218469447*I/2417851639229258349412352], [ 3087979417831061365023111800749855987/151115727451828646838272 + 34441942370802869368851419102423997089*I/604462909807314587353088, -148309181940158040917731426845476175667/604462909807314587353088 - 263987151804109387844966835369350904919*I/9671406556917033397649408, 50259518594816377378747711930008883165/1208925819614629174706176 - 95713974916869240305450001443767979653*I/2417851639229258349412352, 153466447023875527996457943521467271119/2417851639229258349412352 + 517285524891117105834922278517084871349*I/2417851639229258349412352, -29184653615412989036678939366291205575/604462909807314587353088 - 27551322282526322041080173287022121083*I/1208925819614629174706176, 196404220110085511863671393922447671649/1208925819614629174706176 - 1204712019400186021982272049902206202145*I/9671406556917033397649408], [ -2632581805949645784625606590600098779/151115727451828646838272 - 589957435912868015140272627522612771*I/37778931862957161709568, 26727850893953715274702844733506310247/302231454903657293676544 - 10825791956782128799168209600694020481*I/302231454903657293676544, -1036348763702366164044671908440791295/151115727451828646838272 + 3188624571414467767868303105288107375*I/151115727451828646838272, -36814959939970644875593411585393242449/604462909807314587353088 - 18457555789119782404850043842902832647*I/302231454903657293676544, 12454491297984637815063964572803058647/604462909807314587353088 - 340489532842249733975074349495329171*I/302231454903657293676544, -19547211751145597258386735573258916681/604462909807314587353088 + 87299583775782199663414539883938008933*I/1208925819614629174706176], [ -40281994229560039213253423262678393183/604462909807314587353088 - 2939986850065527327299273003299736641*I/604462909807314587353088, 331940684638052085845743020267462794181/2417851639229258349412352 - 284574901963624403933361315517248458969*I/1208925819614629174706176, 6453843623051745485064693628073010961/302231454903657293676544 + 36062454107479732681350914931391590957*I/604462909807314587353088, -147665869053634695632880753646441962067/604462909807314587353088 - 305987938660447291246597544085345123927*I/9671406556917033397649408, 107821369195275772166593879711259469423/2417851639229258349412352 - 11645185518211204108659001435013326687*I/302231454903657293676544, 64121228424717666402009446088588091619/1208925819614629174706176 + 265557133337095047883844369272389762133*I/1208925819614629174706176]]''')) def test_issue_17247_expression_blowup_5(): M = Matrix(6, 6, lambda i, j: 1 + (-1)**(i+j)*I) with dotprodsimp(True): assert M.charpoly('x') == PurePoly(x**6 + (-6 - 6*I)*x**5 + 36*I*x**4, x, domain='EX') def test_issue_17247_expression_blowup_6(): M = Matrix(8, 8, [x+i for i in range (64)]) with dotprodsimp(True): assert M.det('bareiss') == 0 def test_issue_17247_expression_blowup_7(): M = Matrix(6, 6, lambda i, j: 1 + (-1)**(i+j)*I) with dotprodsimp(True): assert M.det('berkowitz') == 0 def test_issue_17247_expression_blowup_8(): M = Matrix(8, 8, [x+i for i in range (64)]) with dotprodsimp(True): assert M.det('lu') == 0 def test_issue_17247_expression_blowup_9(): M = Matrix(8, 8, [x+i for i in range (64)]) with dotprodsimp(True): assert M.rref() == (Matrix([ [1, 0, -1, -2, -3, -4, -5, -6], [0, 1, 2, 3, 4, 5, 6, 7], [0, 0, 0, 0, 0, 0, 0, 0], [0, 0, 0, 0, 0, 0, 0, 0], [0, 0, 0, 0, 0, 0, 0, 0], [0, 0, 0, 0, 0, 0, 0, 0], [0, 0, 0, 0, 0, 0, 0, 0], [0, 0, 0, 0, 0, 0, 0, 0]]), (0, 1)) def test_issue_17247_expression_blowup_10(): M = Matrix(6, 6, lambda i, j: 1 + (-1)**(i+j)*I) with dotprodsimp(True): assert M.cofactor(0, 0) == 0 def test_issue_17247_expression_blowup_11(): M = Matrix(6, 6, lambda i, j: 1 + (-1)**(i+j)*I) with dotprodsimp(True): assert M.cofactor_matrix() == Matrix(6, 6, [0]*36) def test_issue_17247_expression_blowup_12(): M = Matrix(6, 6, lambda i, j: 1 + (-1)**(i+j)*I) with dotprodsimp(True): assert M.eigenvals() == {6: 1, 6*I: 1, 0: 4} def test_issue_17247_expression_blowup_13(): M = Matrix([ [ 0, 1 - x, x + 1, 1 - x], [1 - x, x + 1, 0, x + 1], [ 0, 1 - x, x + 1, 1 - x], [ 0, 0, 1 - x, 0]]) ev = M.eigenvects() assert ev[0] == (0, 2, [Matrix([0, -1, 0, 1])]) assert ev[1][0] == x - sqrt(2)*(x - 1) + 1 assert ev[1][1] == 1 assert ev[1][2][0].expand(deep=False, numer=True) == Matrix([ [(-x + sqrt(2)*(x - 1) - 1)/(x - 1)], [-4*x/(x**2 - 2*x + 1) + (x + 1)*(x - sqrt(2)*(x - 1) + 1)/(x**2 - 2*x + 1)], [(-x + sqrt(2)*(x - 1) - 1)/(x - 1)], [1] ]) assert ev[2][0] == x + sqrt(2)*(x - 1) + 1 assert ev[2][1] == 1 assert ev[2][2][0].expand(deep=False, numer=True) == Matrix([ [(-x - sqrt(2)*(x - 1) - 1)/(x - 1)], [-4*x/(x**2 - 2*x + 1) + (x + 1)*(x + sqrt(2)*(x - 1) + 1)/(x**2 - 2*x + 1)], [(-x - sqrt(2)*(x - 1) - 1)/(x - 1)], [1] ]) def test_issue_17247_expression_blowup_14(): M = Matrix(8, 8, ([1+x, 1-x]*4 + [1-x, 1+x]*4)*4) with dotprodsimp(True): assert M.echelon_form() == Matrix([ [x + 1, 1 - x, x + 1, 1 - x, x + 1, 1 - x, x + 1, 1 - x], [ 0, 4*x, 0, 4*x, 0, 4*x, 0, 4*x], [ 0, 0, 0, 0, 0, 0, 0, 0], [ 0, 0, 0, 0, 0, 0, 0, 0], [ 0, 0, 0, 0, 0, 0, 0, 0], [ 0, 0, 0, 0, 0, 0, 0, 0], [ 0, 0, 0, 0, 0, 0, 0, 0], [ 0, 0, 0, 0, 0, 0, 0, 0]]) def test_issue_17247_expression_blowup_15(): M = Matrix(8, 8, ([1+x, 1-x]*4 + [1-x, 1+x]*4)*4) with dotprodsimp(True): assert M.rowspace() == [Matrix([[x + 1, 1 - x, x + 1, 1 - x, x + 1, 1 - x, x + 1, 1 - x]]), Matrix([[0, 4*x, 0, 4*x, 0, 4*x, 0, 4*x]])] def test_issue_17247_expression_blowup_16(): M = Matrix(8, 8, ([1+x, 1-x]*4 + [1-x, 1+x]*4)*4) with dotprodsimp(True): assert M.columnspace() == [Matrix([[x + 1],[1 - x],[x + 1],[1 - x],[x + 1],[1 - x],[x + 1],[1 - x]]), Matrix([[1 - x],[x + 1],[1 - x],[x + 1],[1 - x],[x + 1],[1 - x],[x + 1]])] def test_issue_17247_expression_blowup_17(): M = Matrix(8, 8, [x+i for i in range (64)]) with dotprodsimp(True): assert M.nullspace() == [ Matrix([[1],[-2],[1],[0],[0],[0],[0],[0]]), Matrix([[2],[-3],[0],[1],[0],[0],[0],[0]]), Matrix([[3],[-4],[0],[0],[1],[0],[0],[0]]), Matrix([[4],[-5],[0],[0],[0],[1],[0],[0]]), Matrix([[5],[-6],[0],[0],[0],[0],[1],[0]]), Matrix([[6],[-7],[0],[0],[0],[0],[0],[1]])] def test_issue_17247_expression_blowup_18(): M = Matrix(6, 6, ([1+x, 1-x]*3 + [1-x, 1+x]*3)*3) with dotprodsimp(True): assert not M.is_nilpotent() def test_issue_17247_expression_blowup_19(): M = Matrix(S('''[ [ -3/4, 0, 1/4 + I/2, 0], [ 0, -177/128 - 1369*I/128, 0, -2063/256 + 541*I/128], [ 1/2 - I, 0, 0, 0], [ 0, 0, 0, -177/128 - 1369*I/128]]''')) with dotprodsimp(True): assert not M.is_diagonalizable() def test_issue_17247_expression_blowup_20(): M = Matrix([ [x + 1, 1 - x, 0, 0], [1 - x, x + 1, 0, x + 1], [ 0, 1 - x, x + 1, 0], [ 0, 0, 0, x + 1]]) with dotprodsimp(True): assert M.diagonalize() == (Matrix([ [1, 1, 0, (x + 1)/(x - 1)], [1, -1, 0, 0], [1, 1, 1, 0], [0, 0, 0, 1]]), Matrix([ [2, 0, 0, 0], [0, 2*x, 0, 0], [0, 0, x + 1, 0], [0, 0, 0, x + 1]])) def test_issue_17247_expression_blowup_21(): M = Matrix(S('''[ [ -3/4, 45/32 - 37*I/16, 0, 0], [-149/64 + 49*I/32, -177/128 - 1369*I/128, 0, -2063/256 + 541*I/128], [ 0, 9/4 + 55*I/16, 2473/256 + 137*I/64, 0], [ 0, 0, 0, -177/128 - 1369*I/128]]''')) with dotprodsimp(True): assert M.inv(method='GE') == Matrix(S('''[ [-26194832/3470993 - 31733264*I/3470993, 156352/3470993 + 10325632*I/3470993, 0, -7741283181072/3306971225785 + 2999007604624*I/3306971225785], [4408224/3470993 - 9675328*I/3470993, -2422272/3470993 + 1523712*I/3470993, 0, -1824666489984/3306971225785 - 1401091949952*I/3306971225785], [-26406945676288/22270005630769 + 10245925485056*I/22270005630769, 7453523312640/22270005630769 + 1601616519168*I/22270005630769, 633088/6416033 - 140288*I/6416033, 872209227109521408/21217636514687010905 + 6066405081802389504*I/21217636514687010905], [0, 0, 0, -11328/952745 + 87616*I/952745]]''')) def test_issue_17247_expression_blowup_22(): M = Matrix(S('''[ [ -3/4, 45/32 - 37*I/16, 0, 0], [-149/64 + 49*I/32, -177/128 - 1369*I/128, 0, -2063/256 + 541*I/128], [ 0, 9/4 + 55*I/16, 2473/256 + 137*I/64, 0], [ 0, 0, 0, -177/128 - 1369*I/128]]''')) with dotprodsimp(True): assert M.inv(method='LU') == Matrix(S('''[ [-26194832/3470993 - 31733264*I/3470993, 156352/3470993 + 10325632*I/3470993, 0, -7741283181072/3306971225785 + 2999007604624*I/3306971225785], [4408224/3470993 - 9675328*I/3470993, -2422272/3470993 + 1523712*I/3470993, 0, -1824666489984/3306971225785 - 1401091949952*I/3306971225785], [-26406945676288/22270005630769 + 10245925485056*I/22270005630769, 7453523312640/22270005630769 + 1601616519168*I/22270005630769, 633088/6416033 - 140288*I/6416033, 872209227109521408/21217636514687010905 + 6066405081802389504*I/21217636514687010905], [0, 0, 0, -11328/952745 + 87616*I/952745]]''')) def test_issue_17247_expression_blowup_23(): M = Matrix(S('''[ [ -3/4, 45/32 - 37*I/16, 0, 0], [-149/64 + 49*I/32, -177/128 - 1369*I/128, 0, -2063/256 + 541*I/128], [ 0, 9/4 + 55*I/16, 2473/256 + 137*I/64, 0], [ 0, 0, 0, -177/128 - 1369*I/128]]''')) with dotprodsimp(True): assert M.inv(method='ADJ').expand() == Matrix(S('''[ [-26194832/3470993 - 31733264*I/3470993, 156352/3470993 + 10325632*I/3470993, 0, -7741283181072/3306971225785 + 2999007604624*I/3306971225785], [4408224/3470993 - 9675328*I/3470993, -2422272/3470993 + 1523712*I/3470993, 0, -1824666489984/3306971225785 - 1401091949952*I/3306971225785], [-26406945676288/22270005630769 + 10245925485056*I/22270005630769, 7453523312640/22270005630769 + 1601616519168*I/22270005630769, 633088/6416033 - 140288*I/6416033, 872209227109521408/21217636514687010905 + 6066405081802389504*I/21217636514687010905], [0, 0, 0, -11328/952745 + 87616*I/952745]]''')) def test_issue_17247_expression_blowup_24(): M = SparseMatrix(S('''[ [ -3/4, 45/32 - 37*I/16, 0, 0], [-149/64 + 49*I/32, -177/128 - 1369*I/128, 0, -2063/256 + 541*I/128], [ 0, 9/4 + 55*I/16, 2473/256 + 137*I/64, 0], [ 0, 0, 0, -177/128 - 1369*I/128]]''')) with dotprodsimp(True): assert M.inv(method='CH') == Matrix(S('''[ [-26194832/3470993 - 31733264*I/3470993, 156352/3470993 + 10325632*I/3470993, 0, -7741283181072/3306971225785 + 2999007604624*I/3306971225785], [4408224/3470993 - 9675328*I/3470993, -2422272/3470993 + 1523712*I/3470993, 0, -1824666489984/3306971225785 - 1401091949952*I/3306971225785], [-26406945676288/22270005630769 + 10245925485056*I/22270005630769, 7453523312640/22270005630769 + 1601616519168*I/22270005630769, 633088/6416033 - 140288*I/6416033, 872209227109521408/21217636514687010905 + 6066405081802389504*I/21217636514687010905], [0, 0, 0, -11328/952745 + 87616*I/952745]]''')) def test_issue_17247_expression_blowup_25(): M = SparseMatrix(S('''[ [ -3/4, 45/32 - 37*I/16, 0, 0], [-149/64 + 49*I/32, -177/128 - 1369*I/128, 0, -2063/256 + 541*I/128], [ 0, 9/4 + 55*I/16, 2473/256 + 137*I/64, 0], [ 0, 0, 0, -177/128 - 1369*I/128]]''')) with dotprodsimp(True): assert M.inv(method='LDL') == Matrix(S('''[ [-26194832/3470993 - 31733264*I/3470993, 156352/3470993 + 10325632*I/3470993, 0, -7741283181072/3306971225785 + 2999007604624*I/3306971225785], [4408224/3470993 - 9675328*I/3470993, -2422272/3470993 + 1523712*I/3470993, 0, -1824666489984/3306971225785 - 1401091949952*I/3306971225785], [-26406945676288/22270005630769 + 10245925485056*I/22270005630769, 7453523312640/22270005630769 + 1601616519168*I/22270005630769, 633088/6416033 - 140288*I/6416033, 872209227109521408/21217636514687010905 + 6066405081802389504*I/21217636514687010905], [0, 0, 0, -11328/952745 + 87616*I/952745]]''')) def test_issue_17247_expression_blowup_26(): M = Matrix(S('''[ [ -3/4, 45/32 - 37*I/16, 1/4 + I/2, -129/64 - 9*I/64, 1/4 - 5*I/16, 65/128 + 87*I/64, -9/32 - I/16, 183/256 - 97*I/128], [-149/64 + 49*I/32, -177/128 - 1369*I/128, 125/64 + 87*I/64, -2063/256 + 541*I/128, 85/256 - 33*I/16, 805/128 + 2415*I/512, -219/128 + 115*I/256, 6301/4096 - 6609*I/1024], [ 1/2 - I, 9/4 + 55*I/16, -3/4, 45/32 - 37*I/16, 1/4 + I/2, -129/64 - 9*I/64, 1/4 - 5*I/16, 65/128 + 87*I/64], [ -5/8 - 39*I/16, 2473/256 + 137*I/64, -149/64 + 49*I/32, -177/128 - 1369*I/128, 125/64 + 87*I/64, -2063/256 + 541*I/128, 85/256 - 33*I/16, 805/128 + 2415*I/512], [ 1 + I, -19/4 + 5*I/4, 1/2 - I, 9/4 + 55*I/16, -3/4, 45/32 - 37*I/16, 1/4 + I/2, -129/64 - 9*I/64], [ 21/8 + I, -537/64 + 143*I/16, -5/8 - 39*I/16, 2473/256 + 137*I/64, -149/64 + 49*I/32, -177/128 - 1369*I/128, 125/64 + 87*I/64, -2063/256 + 541*I/128], [ -2, 17/4 - 13*I/2, 1 + I, -19/4 + 5*I/4, 1/2 - I, 9/4 + 55*I/16, -3/4, 45/32 - 37*I/16], [ 1/4 + 13*I/4, -825/64 - 147*I/32, 21/8 + I, -537/64 + 143*I/16, -5/8 - 39*I/16, 2473/256 + 137*I/64, -149/64 + 49*I/32, -177/128 - 1369*I/128]]''')) with dotprodsimp(True): assert M.rank() == 4 def test_issue_17247_expression_blowup_27(): M = Matrix([ [ 0, 1 - x, x + 1, 1 - x], [1 - x, x + 1, 0, x + 1], [ 0, 1 - x, x + 1, 1 - x], [ 0, 0, 1 - x, 0]]) with dotprodsimp(True): P, J = M.jordan_form() assert P.expand() == Matrix(S('''[ [ 0, 4*x/(x**2 - 2*x + 1), -(-17*x**4 + 12*sqrt(2)*x**4 - 4*sqrt(2)*x**3 + 6*x**3 - 6*x - 4*sqrt(2)*x + 12*sqrt(2) + 17)/(-7*x**4 + 5*sqrt(2)*x**4 - 6*sqrt(2)*x**3 + 8*x**3 - 2*x**2 + 8*x + 6*sqrt(2)*x - 5*sqrt(2) - 7), -(12*sqrt(2)*x**4 + 17*x**4 - 6*x**3 - 4*sqrt(2)*x**3 - 4*sqrt(2)*x + 6*x - 17 + 12*sqrt(2))/(7*x**4 + 5*sqrt(2)*x**4 - 6*sqrt(2)*x**3 - 8*x**3 + 2*x**2 - 8*x + 6*sqrt(2)*x - 5*sqrt(2) + 7)], [x - 1, x/(x - 1) + 1/(x - 1), (-7*x**3 + 5*sqrt(2)*x**3 - x**2 + sqrt(2)*x**2 - sqrt(2)*x - x - 5*sqrt(2) - 7)/(-3*x**3 + 2*sqrt(2)*x**3 - 2*sqrt(2)*x**2 + 3*x**2 + 2*sqrt(2)*x + 3*x - 3 - 2*sqrt(2)), (7*x**3 + 5*sqrt(2)*x**3 + x**2 + sqrt(2)*x**2 - sqrt(2)*x + x - 5*sqrt(2) + 7)/(2*sqrt(2)*x**3 + 3*x**3 - 3*x**2 - 2*sqrt(2)*x**2 - 3*x + 2*sqrt(2)*x - 2*sqrt(2) + 3)], [ 0, 1, -(-3*x**2 + 2*sqrt(2)*x**2 + 2*x - 3 - 2*sqrt(2))/(-x**2 + sqrt(2)*x**2 - 2*sqrt(2)*x + 1 + sqrt(2)), -(2*sqrt(2)*x**2 + 3*x**2 - 2*x - 2*sqrt(2) + 3)/(x**2 + sqrt(2)*x**2 - 2*sqrt(2)*x - 1 + sqrt(2))], [1 - x, 0, 1, 1]]''')).expand() assert J == Matrix(S('''[ [0, 1, 0, 0], [0, 0, 0, 0], [0, 0, x - sqrt(2)*(x - 1) + 1, 0], [0, 0, 0, x + sqrt(2)*(x - 1) + 1]]''')) def test_issue_17247_expression_blowup_28(): M = Matrix(S('''[ [ -3/4, 45/32 - 37*I/16, 0, 0], [-149/64 + 49*I/32, -177/128 - 1369*I/128, 0, -2063/256 + 541*I/128], [ 0, 9/4 + 55*I/16, 2473/256 + 137*I/64, 0], [ 0, 0, 0, -177/128 - 1369*I/128]]''')) with dotprodsimp(True): assert M.singular_values() == S('''[ sqrt(14609315/131072 + sqrt(64789115132571/2147483648 - 2*(25895222463957462655758224991455280215303/633825300114114700748351602688 + sqrt(1213909058710955930446995195883114969038524625997915131236390724543989220134670)*I/22282920707136844948184236032)**(1/3) + 76627253330829751075/(35184372088832*sqrt(64789115132571/4294967296 + 3546944054712886603889144627/(110680464442257309696*(25895222463957462655758224991455280215303/633825300114114700748351602688 + sqrt(1213909058710955930446995195883114969038524625997915131236390724543989220134670)*I/22282920707136844948184236032)**(1/3)) + 2*(25895222463957462655758224991455280215303/633825300114114700748351602688 + sqrt(1213909058710955930446995195883114969038524625997915131236390724543989220134670)*I/22282920707136844948184236032)**(1/3))) - 3546944054712886603889144627/(110680464442257309696*(25895222463957462655758224991455280215303/633825300114114700748351602688 + sqrt(1213909058710955930446995195883114969038524625997915131236390724543989220134670)*I/22282920707136844948184236032)**(1/3)))/2 + sqrt(64789115132571/4294967296 + 3546944054712886603889144627/(110680464442257309696*(25895222463957462655758224991455280215303/633825300114114700748351602688 + sqrt(1213909058710955930446995195883114969038524625997915131236390724543989220134670)*I/22282920707136844948184236032)**(1/3)) + 2*(25895222463957462655758224991455280215303/633825300114114700748351602688 + sqrt(1213909058710955930446995195883114969038524625997915131236390724543989220134670)*I/22282920707136844948184236032)**(1/3))/2), sqrt(14609315/131072 - sqrt(64789115132571/2147483648 - 2*(25895222463957462655758224991455280215303/633825300114114700748351602688 + sqrt(1213909058710955930446995195883114969038524625997915131236390724543989220134670)*I/22282920707136844948184236032)**(1/3) + 76627253330829751075/(35184372088832*sqrt(64789115132571/4294967296 + 3546944054712886603889144627/(110680464442257309696*(25895222463957462655758224991455280215303/633825300114114700748351602688 + sqrt(1213909058710955930446995195883114969038524625997915131236390724543989220134670)*I/22282920707136844948184236032)**(1/3)) + 2*(25895222463957462655758224991455280215303/633825300114114700748351602688 + sqrt(1213909058710955930446995195883114969038524625997915131236390724543989220134670)*I/22282920707136844948184236032)**(1/3))) - 3546944054712886603889144627/(110680464442257309696*(25895222463957462655758224991455280215303/633825300114114700748351602688 + sqrt(1213909058710955930446995195883114969038524625997915131236390724543989220134670)*I/22282920707136844948184236032)**(1/3)))/2 + sqrt(64789115132571/4294967296 + 3546944054712886603889144627/(110680464442257309696*(25895222463957462655758224991455280215303/633825300114114700748351602688 + sqrt(1213909058710955930446995195883114969038524625997915131236390724543989220134670)*I/22282920707136844948184236032)**(1/3)) + 2*(25895222463957462655758224991455280215303/633825300114114700748351602688 + sqrt(1213909058710955930446995195883114969038524625997915131236390724543989220134670)*I/22282920707136844948184236032)**(1/3))/2), sqrt(14609315/131072 - sqrt(64789115132571/4294967296 + 3546944054712886603889144627/(110680464442257309696*(25895222463957462655758224991455280215303/633825300114114700748351602688 + sqrt(1213909058710955930446995195883114969038524625997915131236390724543989220134670)*I/22282920707136844948184236032)**(1/3)) + 2*(25895222463957462655758224991455280215303/633825300114114700748351602688 + sqrt(1213909058710955930446995195883114969038524625997915131236390724543989220134670)*I/22282920707136844948184236032)**(1/3))/2 + sqrt(64789115132571/2147483648 - 2*(25895222463957462655758224991455280215303/633825300114114700748351602688 + sqrt(1213909058710955930446995195883114969038524625997915131236390724543989220134670)*I/22282920707136844948184236032)**(1/3) - 76627253330829751075/(35184372088832*sqrt(64789115132571/4294967296 + 3546944054712886603889144627/(110680464442257309696*(25895222463957462655758224991455280215303/633825300114114700748351602688 + sqrt(1213909058710955930446995195883114969038524625997915131236390724543989220134670)*I/22282920707136844948184236032)**(1/3)) + 2*(25895222463957462655758224991455280215303/633825300114114700748351602688 + sqrt(1213909058710955930446995195883114969038524625997915131236390724543989220134670)*I/22282920707136844948184236032)**(1/3))) - 3546944054712886603889144627/(110680464442257309696*(25895222463957462655758224991455280215303/633825300114114700748351602688 + sqrt(1213909058710955930446995195883114969038524625997915131236390724543989220134670)*I/22282920707136844948184236032)**(1/3)))/2), sqrt(14609315/131072 - sqrt(64789115132571/4294967296 + 3546944054712886603889144627/(110680464442257309696*(25895222463957462655758224991455280215303/633825300114114700748351602688 + sqrt(1213909058710955930446995195883114969038524625997915131236390724543989220134670)*I/22282920707136844948184236032)**(1/3)) + 2*(25895222463957462655758224991455280215303/633825300114114700748351602688 + sqrt(1213909058710955930446995195883114969038524625997915131236390724543989220134670)*I/22282920707136844948184236032)**(1/3))/2 - sqrt(64789115132571/2147483648 - 2*(25895222463957462655758224991455280215303/633825300114114700748351602688 + sqrt(1213909058710955930446995195883114969038524625997915131236390724543989220134670)*I/22282920707136844948184236032)**(1/3) - 76627253330829751075/(35184372088832*sqrt(64789115132571/4294967296 + 3546944054712886603889144627/(110680464442257309696*(25895222463957462655758224991455280215303/633825300114114700748351602688 + sqrt(1213909058710955930446995195883114969038524625997915131236390724543989220134670)*I/22282920707136844948184236032)**(1/3)) + 2*(25895222463957462655758224991455280215303/633825300114114700748351602688 + sqrt(1213909058710955930446995195883114969038524625997915131236390724543989220134670)*I/22282920707136844948184236032)**(1/3))) - 3546944054712886603889144627/(110680464442257309696*(25895222463957462655758224991455280215303/633825300114114700748351602688 + sqrt(1213909058710955930446995195883114969038524625997915131236390724543989220134670)*I/22282920707136844948184236032)**(1/3)))/2)]''') def test_issue_16823(): # This still needs to be fixed if not using dotprodsimp. M = Matrix(S('''[ [1+I,-19/4+5/4*I,1/2-I,9/4+55/16*I,-3/4,45/32-37/16*I,1/4+1/2*I,-129/64-9/64*I,1/4-5/16*I,65/128+87/64*I,-9/32-1/16*I,183/256-97/128*I,3/64+13/64*I,-23/32-59/256*I,15/128-3/32*I,19/256+551/1024*I], [21/8+I,-537/64+143/16*I,-5/8-39/16*I,2473/256+137/64*I,-149/64+49/32*I,-177/128-1369/128*I,125/64+87/64*I,-2063/256+541/128*I,85/256-33/16*I,805/128+2415/512*I,-219/128+115/256*I,6301/4096-6609/1024*I,119/128+143/128*I,-10879/2048+4343/4096*I,129/256-549/512*I,42533/16384+29103/8192*I], [-2,17/4-13/2*I,1+I,-19/4+5/4*I,1/2-I,9/4+55/16*I,-3/4,45/32-37/16*I,1/4+1/2*I,-129/64-9/64*I,1/4-5/16*I,65/128+87/64*I,-9/32-1/16*I,183/256-97/128*I,3/64+13/64*I,-23/32-59/256*I], [1/4+13/4*I,-825/64-147/32*I,21/8+I,-537/64+143/16*I,-5/8-39/16*I,2473/256+137/64*I,-149/64+49/32*I,-177/128-1369/128*I,125/64+87/64*I,-2063/256+541/128*I,85/256-33/16*I,805/128+2415/512*I,-219/128+115/256*I,6301/4096-6609/1024*I,119/128+143/128*I,-10879/2048+4343/4096*I], [-4*I,27/2+6*I,-2,17/4-13/2*I,1+I,-19/4+5/4*I,1/2-I,9/4+55/16*I,-3/4,45/32-37/16*I,1/4+1/2*I,-129/64-9/64*I,1/4-5/16*I,65/128+87/64*I,-9/32-1/16*I,183/256-97/128*I], [1/4+5/2*I,-23/8-57/16*I,1/4+13/4*I,-825/64-147/32*I,21/8+I,-537/64+143/16*I,-5/8-39/16*I,2473/256+137/64*I,-149/64+49/32*I,-177/128-1369/128*I,125/64+87/64*I,-2063/256+541/128*I,85/256-33/16*I,805/128+2415/512*I,-219/128+115/256*I,6301/4096-6609/1024*I], [-4,9-5*I,-4*I,27/2+6*I,-2,17/4-13/2*I,1+I,-19/4+5/4*I,1/2-I,9/4+55/16*I,-3/4,45/32-37/16*I,1/4+1/2*I,-129/64-9/64*I,1/4-5/16*I,65/128+87/64*I], [-2*I,119/8+29/4*I,1/4+5/2*I,-23/8-57/16*I,1/4+13/4*I,-825/64-147/32*I,21/8+I,-537/64+143/16*I,-5/8-39/16*I,2473/256+137/64*I,-149/64+49/32*I,-177/128-1369/128*I,125/64+87/64*I,-2063/256+541/128*I,85/256-33/16*I,805/128+2415/512*I], [0,-6,-4,9-5*I,-4*I,27/2+6*I,-2,17/4-13/2*I,1+I,-19/4+5/4*I,1/2-I,9/4+55/16*I,-3/4,45/32-37/16*I,1/4+1/2*I,-129/64-9/64*I], [1,-9/4+3*I,-2*I,119/8+29/4*I,1/4+5/2*I,-23/8-57/16*I,1/4+13/4*I,-825/64-147/32*I,21/8+I,-537/64+143/16*I,-5/8-39/16*I,2473/256+137/64*I,-149/64+49/32*I,-177/128-1369/128*I,125/64+87/64*I,-2063/256+541/128*I], [0,-4*I,0,-6,-4,9-5*I,-4*I,27/2+6*I,-2,17/4-13/2*I,1+I,-19/4+5/4*I,1/2-I,9/4+55/16*I,-3/4,45/32-37/16*I], [0,1/4+1/2*I,1,-9/4+3*I,-2*I,119/8+29/4*I,1/4+5/2*I,-23/8-57/16*I,1/4+13/4*I,-825/64-147/32*I,21/8+I,-537/64+143/16*I,-5/8-39/16*I,2473/256+137/64*I,-149/64+49/32*I,-177/128-1369/128*I]]''')) with dotprodsimp(True): assert M.rank() == 8 def test_issue_18531(): # solve_linear_system still needs fixing but the rref works. M = Matrix([ [1, 1, 1, 1, 1, 0, 1, 0, 0], [1 + sqrt(2), -1 + sqrt(2), 1 - sqrt(2), -sqrt(2) - 1, 1, 1, -1, 1, 1], [-5 + 2*sqrt(2), -5 - 2*sqrt(2), -5 - 2*sqrt(2), -5 + 2*sqrt(2), -7, 2, -7, -2, 0], [-3*sqrt(2) - 1, 1 - 3*sqrt(2), -1 + 3*sqrt(2), 1 + 3*sqrt(2), -7, -5, 7, -5, 3], [7 - 4*sqrt(2), 4*sqrt(2) + 7, 4*sqrt(2) + 7, 7 - 4*sqrt(2), 7, -12, 7, 12, 0], [-1 + 3*sqrt(2), 1 + 3*sqrt(2), -3*sqrt(2) - 1, 1 - 3*sqrt(2), 7, -5, -7, -5, 3], [-3 + 2*sqrt(2), -3 - 2*sqrt(2), -3 - 2*sqrt(2), -3 + 2*sqrt(2), -1, 2, -1, -2, 0], [1 - sqrt(2), -sqrt(2) - 1, 1 + sqrt(2), -1 + sqrt(2), -1, 1, 1, 1, 1] ]) with dotprodsimp(True): assert M.rref() == (Matrix([ [1, 0, 0, 0, 0, 0, 0, 0, 1/2], [0, 1, 0, 0, 0, 0, 0, 0, -1/2], [0, 0, 1, 0, 0, 0, 0, 0, 1/2], [0, 0, 0, 1, 0, 0, 0, 0, -1/2], [0, 0, 0, 0, 1, 0, 0, 0, 0], [0, 0, 0, 0, 0, 1, 0, 0, -1/2], [0, 0, 0, 0, 0, 0, 1, 0, 0], [0, 0, 0, 0, 0, 0, 0, 1, -1/2]]), (0, 1, 2, 3, 4, 5, 6, 7)) def test_creation(): raises(ValueError, lambda: Matrix(5, 5, range(20))) raises(ValueError, lambda: Matrix(5, -1, [])) raises(IndexError, lambda: Matrix((1, 2))[2]) with raises(IndexError): Matrix((1, 2))[1:2] = 5 with raises(IndexError): Matrix((1, 2))[3] = 5 assert Matrix() == Matrix([]) == Matrix([[]]) == Matrix(0, 0, []) # anything used to be allowed in a matrix with warns_deprecated_sympy(): assert Matrix([[[], ()]]).tolist() == [[[], ()]] with warns_deprecated_sympy(): assert Matrix([[[], ()]]).T.tolist() == [[[]], [()]] a = Matrix([[x, 0], [0, 0]]) m = a assert m.cols == m.rows assert m.cols == 2 assert m[:] == [x, 0, 0, 0] b = Matrix(2, 2, [x, 0, 0, 0]) m = b assert m.cols == m.rows assert m.cols == 2 assert m[:] == [x, 0, 0, 0] assert a == b assert Matrix(b) == b c23 = Matrix(2, 3, range(1, 7)) c13 = Matrix(1, 3, range(7, 10)) c = Matrix([c23, c13]) assert c.cols == 3 assert c.rows == 3 assert c[:] == [1, 2, 3, 4, 5, 6, 7, 8, 9] assert Matrix(eye(2)) == eye(2) assert ImmutableMatrix(ImmutableMatrix(eye(2))) == ImmutableMatrix(eye(2)) assert ImmutableMatrix(c) == c.as_immutable() assert Matrix(ImmutableMatrix(c)) == ImmutableMatrix(c).as_mutable() assert c is not Matrix(c) dat = [[ones(3,2), ones(3,3)*2], [ones(2,3)*3, ones(2,2)*4]] M = Matrix(dat) assert M == Matrix([ [1, 1, 2, 2, 2], [1, 1, 2, 2, 2], [1, 1, 2, 2, 2], [3, 3, 3, 4, 4], [3, 3, 3, 4, 4]]) assert M.tolist() != dat # keep block form if evaluate=False assert Matrix(dat, evaluate=False).tolist() == dat A = MatrixSymbol("A", 2, 2) dat = [ones(2), A] assert Matrix(dat) == Matrix([ [ 1, 1], [ 1, 1], [A[0, 0], A[0, 1]], [A[1, 0], A[1, 1]]]) with warns_deprecated_sympy(): assert Matrix(dat, evaluate=False).tolist() == [[i] for i in dat] # 0-dim tolerance assert Matrix([ones(2), ones(0)]) == Matrix([ones(2)]) raises(ValueError, lambda: Matrix([ones(2), ones(0, 3)])) raises(ValueError, lambda: Matrix([ones(2), ones(3, 0)])) def test_irregular_block(): assert Matrix.irregular(3, ones(2,1), ones(3,3)*2, ones(2,2)*3, ones(1,1)*4, ones(2,2)*5, ones(1,2)*6, ones(1,2)*7) == Matrix([ [1, 2, 2, 2, 3, 3], [1, 2, 2, 2, 3, 3], [4, 2, 2, 2, 5, 5], [6, 6, 7, 7, 5, 5]]) def test_tolist(): lst = [[S.One, S.Half, x*y, S.Zero], [x, y, z, x**2], [y, -S.One, z*x, 3]] m = Matrix(lst) assert m.tolist() == lst def test_as_mutable(): assert zeros(0, 3).as_mutable() == zeros(0, 3) assert zeros(0, 3).as_immutable() == ImmutableMatrix(zeros(0, 3)) assert zeros(3, 0).as_immutable() == ImmutableMatrix(zeros(3, 0)) def test_slicing(): m0 = eye(4) assert m0[:3, :3] == eye(3) assert m0[2:4, 0:2] == zeros(2) m1 = Matrix(3, 3, lambda i, j: i + j) assert m1[0, :] == Matrix(1, 3, (0, 1, 2)) assert m1[1:3, 1] == Matrix(2, 1, (2, 3)) m2 = Matrix([[0, 1, 2, 3], [4, 5, 6, 7], [8, 9, 10, 11], [12, 13, 14, 15]]) assert m2[:, -1] == Matrix(4, 1, [3, 7, 11, 15]) assert m2[-2:, :] == Matrix([[8, 9, 10, 11], [12, 13, 14, 15]]) def test_submatrix_assignment(): m = zeros(4) m[2:4, 2:4] = eye(2) assert m == Matrix(((0, 0, 0, 0), (0, 0, 0, 0), (0, 0, 1, 0), (0, 0, 0, 1))) m[:2, :2] = eye(2) assert m == eye(4) m[:, 0] = Matrix(4, 1, (1, 2, 3, 4)) assert m == Matrix(((1, 0, 0, 0), (2, 1, 0, 0), (3, 0, 1, 0), (4, 0, 0, 1))) m[:, :] = zeros(4) assert m == zeros(4) m[:, :] = [(1, 2, 3, 4), (5, 6, 7, 8), (9, 10, 11, 12), (13, 14, 15, 16)] assert m == Matrix(((1, 2, 3, 4), (5, 6, 7, 8), (9, 10, 11, 12), (13, 14, 15, 16))) m[:2, 0] = [0, 0] assert m == Matrix(((0, 2, 3, 4), (0, 6, 7, 8), (9, 10, 11, 12), (13, 14, 15, 16))) def test_extract(): m = Matrix(4, 3, lambda i, j: i*3 + j) assert m.extract([0, 1, 3], [0, 1]) == Matrix(3, 2, [0, 1, 3, 4, 9, 10]) assert m.extract([0, 3], [0, 0, 2]) == Matrix(2, 3, [0, 0, 2, 9, 9, 11]) assert m.extract(range(4), range(3)) == m raises(IndexError, lambda: m.extract([4], [0])) raises(IndexError, lambda: m.extract([0], [3])) def test_reshape(): m0 = eye(3) assert m0.reshape(1, 9) == Matrix(1, 9, (1, 0, 0, 0, 1, 0, 0, 0, 1)) m1 = Matrix(3, 4, lambda i, j: i + j) assert m1.reshape( 4, 3) == Matrix(((0, 1, 2), (3, 1, 2), (3, 4, 2), (3, 4, 5))) assert m1.reshape(2, 6) == Matrix(((0, 1, 2, 3, 1, 2), (3, 4, 2, 3, 4, 5))) def test_applyfunc(): m0 = eye(3) assert m0.applyfunc(lambda x: 2*x) == eye(3)*2 assert m0.applyfunc(lambda x: 0) == zeros(3) def test_expand(): m0 = Matrix([[x*(x + y), 2], [((x + y)*y)*x, x*(y + x*(x + y))]]) # Test if expand() returns a matrix m1 = m0.expand() assert m1 == Matrix( [[x*y + x**2, 2], [x*y**2 + y*x**2, x*y + y*x**2 + x**3]]) a = Symbol('a', real=True) assert Matrix([exp(I*a)]).expand(complex=True) == \ Matrix([cos(a) + I*sin(a)]) assert Matrix([[0, 1, 2], [0, 0, -1], [0, 0, 0]]).exp() == Matrix([ [1, 1, Rational(3, 2)], [0, 1, -1], [0, 0, 1]] ) def test_refine(): m0 = Matrix([[Abs(x)**2, sqrt(x**2)], [sqrt(x**2)*Abs(y)**2, sqrt(y**2)*Abs(x)**2]]) m1 = m0.refine(Q.real(x) & Q.real(y)) assert m1 == Matrix([[x**2, Abs(x)], [y**2*Abs(x), x**2*Abs(y)]]) m1 = m0.refine(Q.positive(x) & Q.positive(y)) assert m1 == Matrix([[x**2, x], [x*y**2, x**2*y]]) m1 = m0.refine(Q.negative(x) & Q.negative(y)) assert m1 == Matrix([[x**2, -x], [-x*y**2, -x**2*y]]) def test_random(): M = randMatrix(3, 3) M = randMatrix(3, 3, seed=3) assert M == randMatrix(3, 3, seed=3) M = randMatrix(3, 4, 0, 150) M = randMatrix(3, seed=4, symmetric=True) assert M == randMatrix(3, seed=4, symmetric=True) S = M.copy() S.simplify() assert S == M # doesn't fail when elements are Numbers, not int rng = random.Random(4) assert M == randMatrix(3, symmetric=True, prng=rng) # Ensure symmetry for size in (10, 11): # Test odd and even for percent in (100, 70, 30): M = randMatrix(size, symmetric=True, percent=percent, prng=rng) assert M == M.T M = randMatrix(10, min=1, percent=70) zero_count = 0 for i in range(M.shape[0]): for j in range(M.shape[1]): if M[i, j] == 0: zero_count += 1 assert zero_count == 30 def test_inverse(): A = eye(4) assert A.inv() == eye(4) assert A.inv(method="LU") == eye(4) assert A.inv(method="ADJ") == eye(4) assert A.inv(method="CH") == eye(4) assert A.inv(method="LDL") == eye(4) assert A.inv(method="QR") == eye(4) A = Matrix([[2, 3, 5], [3, 6, 2], [8, 3, 6]]) Ainv = A.inv() assert A*Ainv == eye(3) assert A.inv(method="LU") == Ainv assert A.inv(method="ADJ") == Ainv assert A.inv(method="CH") == Ainv assert A.inv(method="LDL") == Ainv assert A.inv(method="QR") == Ainv AA = Matrix([[0, 0, 0, 0, 1, 0, 0, 1, 0, 1, 1, 1, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 0], [1, 0, 1, 0, 0, 1, 0, 0, 1, 0, 1, 0, 1, 1, 1, 0, 1, 1, 0, 0, 0, 0, 0, 1, 0], [1, 1, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 0, 1, 1, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1], [1, 0, 0, 0, 0, 0, 1, 1, 0, 0, 1, 1, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 1, 0, 0], [1, 0, 0, 1, 1, 1, 0, 1, 0, 0, 1, 0, 0, 1, 1, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0], [1, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 0, 0, 0, 1, 1, 0, 1], [0, 1, 1, 1, 0, 0, 0, 0, 1, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0], [1, 1, 0, 0, 0, 1, 1, 0, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 0, 1, 1, 0, 1, 1], [0, 0, 1, 1, 1, 0, 0, 1, 1, 0, 1, 1, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 1], [1, 0, 1, 1, 1, 0, 1, 0, 0, 1, 1, 0, 1, 1, 0, 1, 1, 1, 1, 0, 1, 1, 1, 0, 0], [0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 1, 0, 1, 0, 1, 1, 0, 0, 1, 0, 0, 0, 1, 1, 0], [1, 0, 0, 1, 0, 1, 0, 1, 1, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 0, 0], [0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1], [1, 1, 1, 0, 1, 0, 0, 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 1, 0, 1, 0, 1, 1, 0], [0, 1, 0, 0, 0, 0, 1, 1, 0, 1, 1, 0, 0, 0, 0, 1, 0, 1, 1, 1, 0, 0, 1, 0, 0], [1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 0, 0], [0, 0, 0, 1, 0, 1, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 1, 0, 1, 0, 1, 1, 0, 1], [0, 1, 0, 1, 0, 0, 0, 0, 1, 1, 1, 0, 0, 1, 1, 1, 0, 0, 1, 0, 1, 1, 0, 1, 1], [1, 0, 1, 1, 0, 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 0, 0, 0, 0, 1, 0, 0, 1, 0, 1], [0, 0, 0, 1, 0, 0, 1, 1, 0, 1, 1, 0, 1, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0], [1, 0, 0, 0, 0, 1, 0, 1, 0, 0, 1, 1, 0, 1, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1], [0, 0, 1, 1, 0, 1, 0, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 1], [0, 0, 0, 0, 0, 1, 1, 1, 0, 1, 1, 1, 0, 0, 0, 1, 0, 1, 1, 0, 1, 1, 0, 0, 0], [0, 0, 1, 0, 1, 1, 0, 1, 1, 1, 0, 0, 1, 0, 1, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0], [0, 0, 0, 1, 1, 0, 1, 1, 1, 0, 0, 1, 0, 1, 0, 1, 1, 0, 1, 1, 1, 0, 0, 1, 0]]) assert AA.inv(method="BLOCK") * AA == eye(AA.shape[0]) # test that immutability is not a problem cls = ImmutableMatrix m = cls([[48, 49, 31], [ 9, 71, 94], [59, 28, 65]]) assert all(type(m.inv(s)) is cls for s in 'GE ADJ LU CH LDL QR'.split()) cls = ImmutableSparseMatrix m = cls([[48, 49, 31], [ 9, 71, 94], [59, 28, 65]]) assert all(type(m.inv(s)) is cls for s in 'GE ADJ LU CH LDL QR'.split()) def test_matrix_inverse_mod(): A = Matrix(2, 1, [1, 0]) raises(NonSquareMatrixError, lambda: A.inv_mod(2)) A = Matrix(2, 2, [1, 0, 0, 0]) raises(ValueError, lambda: A.inv_mod(2)) A = Matrix(2, 2, [1, 2, 3, 4]) Ai = Matrix(2, 2, [1, 1, 0, 1]) assert A.inv_mod(3) == Ai A = Matrix(2, 2, [1, 0, 0, 1]) assert A.inv_mod(2) == A A = Matrix(3, 3, [1, 2, 3, 4, 5, 6, 7, 8, 9]) raises(ValueError, lambda: A.inv_mod(5)) A = Matrix(3, 3, [5, 1, 3, 2, 6, 0, 2, 1, 1]) Ai = Matrix(3, 3, [6, 8, 0, 1, 5, 6, 5, 6, 4]) assert A.inv_mod(9) == Ai A = Matrix(3, 3, [1, 6, -3, 4, 1, -5, 3, -5, 5]) Ai = Matrix(3, 3, [4, 3, 3, 1, 2, 5, 1, 5, 1]) assert A.inv_mod(6) == Ai A = Matrix(3, 3, [1, 6, 1, 4, 1, 5, 3, 2, 5]) Ai = Matrix(3, 3, [6, 0, 3, 6, 6, 4, 1, 6, 1]) assert A.inv_mod(7) == Ai def test_jacobian_hessian(): L = Matrix(1, 2, [x**2*y, 2*y**2 + x*y]) syms = [x, y] assert L.jacobian(syms) == Matrix([[2*x*y, x**2], [y, 4*y + x]]) L = Matrix(1, 2, [x, x**2*y**3]) assert L.jacobian(syms) == Matrix([[1, 0], [2*x*y**3, x**2*3*y**2]]) f = x**2*y syms = [x, y] assert hessian(f, syms) == Matrix([[2*y, 2*x], [2*x, 0]]) f = x**2*y**3 assert hessian(f, syms) == \ Matrix([[2*y**3, 6*x*y**2], [6*x*y**2, 6*x**2*y]]) f = z + x*y**2 g = x**2 + 2*y**3 ans = Matrix([[0, 2*y], [2*y, 2*x]]) assert ans == hessian(f, Matrix([x, y])) assert ans == hessian(f, Matrix([x, y]).T) assert hessian(f, (y, x), [g]) == Matrix([ [ 0, 6*y**2, 2*x], [6*y**2, 2*x, 2*y], [ 2*x, 2*y, 0]]) def test_wronskian(): assert wronskian([cos(x), sin(x)], x) == cos(x)**2 + sin(x)**2 assert wronskian([exp(x), exp(2*x)], x) == exp(3*x) assert wronskian([exp(x), x], x) == exp(x) - x*exp(x) assert wronskian([1, x, x**2], x) == 2 w1 = -6*exp(x)*sin(x)*x + 6*cos(x)*exp(x)*x**2 - 6*exp(x)*cos(x)*x - \ exp(x)*cos(x)*x**3 + exp(x)*sin(x)*x**3 assert wronskian([exp(x), cos(x), x**3], x).expand() == w1 assert wronskian([exp(x), cos(x), x**3], x, method='berkowitz').expand() \ == w1 w2 = -x**3*cos(x)**2 - x**3*sin(x)**2 - 6*x*cos(x)**2 - 6*x*sin(x)**2 assert wronskian([sin(x), cos(x), x**3], x).expand() == w2 assert wronskian([sin(x), cos(x), x**3], x, method='berkowitz').expand() \ == w2 assert wronskian([], x) == 1 def test_subs(): assert Matrix([[1, x], [x, 4]]).subs(x, 5) == Matrix([[1, 5], [5, 4]]) assert Matrix([[x, 2], [x + y, 4]]).subs([[x, -1], [y, -2]]) == \ Matrix([[-1, 2], [-3, 4]]) assert Matrix([[x, 2], [x + y, 4]]).subs([(x, -1), (y, -2)]) == \ Matrix([[-1, 2], [-3, 4]]) assert Matrix([[x, 2], [x + y, 4]]).subs({x: -1, y: -2}) == \ Matrix([[-1, 2], [-3, 4]]) assert Matrix([x*y]).subs({x: y - 1, y: x - 1}, simultaneous=True) == \ Matrix([(x - 1)*(y - 1)]) for cls in classes: assert Matrix([[2, 0], [0, 2]]) == cls.eye(2).subs(1, 2) def test_xreplace(): assert Matrix([[1, x], [x, 4]]).xreplace({x: 5}) == \ Matrix([[1, 5], [5, 4]]) assert Matrix([[x, 2], [x + y, 4]]).xreplace({x: -1, y: -2}) == \ Matrix([[-1, 2], [-3, 4]]) for cls in classes: assert Matrix([[2, 0], [0, 2]]) == cls.eye(2).xreplace({1: 2}) def test_simplify(): n = Symbol('n') f = Function('f') M = Matrix([[ 1/x + 1/y, (x + x*y) / x ], [ (f(x) + y*f(x))/f(x), 2 * (1/n - cos(n * pi)/n) / pi ]]) M.simplify() assert M == Matrix([[ (x + y)/(x * y), 1 + y ], [ 1 + y, 2*((1 - 1*cos(pi*n))/(pi*n)) ]]) eq = (1 + x)**2 M = Matrix([[eq]]) M.simplify() assert M == Matrix([[eq]]) M.simplify(ratio=oo) == M assert M == Matrix([[eq.simplify(ratio=oo)]]) def test_transpose(): M = Matrix([[1, 2, 3, 4, 5, 6, 7, 8, 9, 0], [1, 2, 3, 4, 5, 6, 7, 8, 9, 0]]) assert M.T == Matrix( [ [1, 1], [2, 2], [3, 3], [4, 4], [5, 5], [6, 6], [7, 7], [8, 8], [9, 9], [0, 0] ]) assert M.T.T == M assert M.T == M.transpose() def test_conjugate(): M = Matrix([[0, I, 5], [1, 2, 0]]) assert M.T == Matrix([[0, 1], [I, 2], [5, 0]]) assert M.C == Matrix([[0, -I, 5], [1, 2, 0]]) assert M.C == M.conjugate() assert M.H == M.T.C assert M.H == Matrix([[ 0, 1], [-I, 2], [ 5, 0]]) def test_conj_dirac(): raises(AttributeError, lambda: eye(3).D) M = Matrix([[1, I, I, I], [0, 1, I, I], [0, 0, 1, I], [0, 0, 0, 1]]) assert M.D == Matrix([[ 1, 0, 0, 0], [-I, 1, 0, 0], [-I, -I, -1, 0], [-I, -I, I, -1]]) def test_trace(): M = Matrix([[1, 0, 0], [0, 5, 0], [0, 0, 8]]) assert M.trace() == 14 def test_shape(): M = Matrix([[x, 0, 0], [0, y, 0]]) assert M.shape == (2, 3) def test_col_row_op(): M = Matrix([[x, 0, 0], [0, y, 0]]) M.row_op(1, lambda r, j: r + j + 1) assert M == Matrix([[x, 0, 0], [1, y + 2, 3]]) M.col_op(0, lambda c, j: c + y**j) assert M == Matrix([[x + 1, 0, 0], [1 + y, y + 2, 3]]) # neither row nor slice give copies that allow the original matrix to # be changed assert M.row(0) == Matrix([[x + 1, 0, 0]]) r1 = M.row(0) r1[0] = 42 assert M[0, 0] == x + 1 r1 = M[0, :-1] # also testing negative slice r1[0] = 42 assert M[0, 0] == x + 1 c1 = M.col(0) assert c1 == Matrix([x + 1, 1 + y]) c1[0] = 0 assert M[0, 0] == x + 1 c1 = M[:, 0] c1[0] = 42 assert M[0, 0] == x + 1 def test_zip_row_op(): for cls in classes[:2]: # XXX: immutable matrices don't support row ops M = cls.eye(3) M.zip_row_op(1, 0, lambda v, u: v + 2*u) assert M == cls([[1, 0, 0], [2, 1, 0], [0, 0, 1]]) M = cls.eye(3)*2 M[0, 1] = -1 M.zip_row_op(1, 0, lambda v, u: v + 2*u); M assert M == cls([[2, -1, 0], [4, 0, 0], [0, 0, 2]]) def test_issue_3950(): m = Matrix([1, 2, 3]) a = Matrix([1, 2, 3]) b = Matrix([2, 2, 3]) assert not (m in []) assert not (m in [1]) assert m != 1 assert m == a assert m != b def test_issue_3981(): class Index1: def __index__(self): return 1 class Index2: def __index__(self): return 2 index1 = Index1() index2 = Index2() m = Matrix([1, 2, 3]) assert m[index2] == 3 m[index2] = 5 assert m[2] == 5 m = Matrix([[1, 2, 3], [4, 5, 6]]) assert m[index1, index2] == 6 assert m[1, index2] == 6 assert m[index1, 2] == 6 m[index1, index2] = 4 assert m[1, 2] == 4 m[1, index2] = 6 assert m[1, 2] == 6 m[index1, 2] = 8 assert m[1, 2] == 8 def test_evalf(): a = Matrix([sqrt(5), 6]) assert all(a.evalf()[i] == a[i].evalf() for i in range(2)) assert all(a.evalf(2)[i] == a[i].evalf(2) for i in range(2)) assert all(a.n(2)[i] == a[i].n(2) for i in range(2)) def test_is_symbolic(): a = Matrix([[x, x], [x, x]]) assert a.is_symbolic() is True a = Matrix([[1, 2, 3, 4], [5, 6, 7, 8]]) assert a.is_symbolic() is False a = Matrix([[1, 2, 3, 4], [5, 6, x, 8]]) assert a.is_symbolic() is True a = Matrix([[1, x, 3]]) assert a.is_symbolic() is True a = Matrix([[1, 2, 3]]) assert a.is_symbolic() is False a = Matrix([[1], [x], [3]]) assert a.is_symbolic() is True a = Matrix([[1], [2], [3]]) assert a.is_symbolic() is False def test_is_upper(): a = Matrix([[1, 2, 3]]) assert a.is_upper is True a = Matrix([[1], [2], [3]]) assert a.is_upper is False a = zeros(4, 2) assert a.is_upper is True def test_is_lower(): a = Matrix([[1, 2, 3]]) assert a.is_lower is False a = Matrix([[1], [2], [3]]) assert a.is_lower is True def test_is_nilpotent(): a = Matrix(4, 4, [0, 2, 1, 6, 0, 0, 1, 2, 0, 0, 0, 3, 0, 0, 0, 0]) assert a.is_nilpotent() a = Matrix([[1, 0], [0, 1]]) assert not a.is_nilpotent() a = Matrix([]) assert a.is_nilpotent() def test_zeros_ones_fill(): n, m = 3, 5 a = zeros(n, m) a.fill( 5 ) b = 5 * ones(n, m) assert a == b assert a.rows == b.rows == 3 assert a.cols == b.cols == 5 assert a.shape == b.shape == (3, 5) assert zeros(2) == zeros(2, 2) assert ones(2) == ones(2, 2) assert zeros(2, 3) == Matrix(2, 3, [0]*6) assert ones(2, 3) == Matrix(2, 3, [1]*6) def test_empty_zeros(): a = zeros(0) assert a == Matrix() a = zeros(0, 2) assert a.rows == 0 assert a.cols == 2 a = zeros(2, 0) assert a.rows == 2 assert a.cols == 0 def test_issue_3749(): a = Matrix([[x**2, x*y], [x*sin(y), x*cos(y)]]) assert a.diff(x) == Matrix([[2*x, y], [sin(y), cos(y)]]) assert Matrix([ [x, -x, x**2], [exp(x), 1/x - exp(-x), x + 1/x]]).limit(x, oo) == \ Matrix([[oo, -oo, oo], [oo, 0, oo]]) assert Matrix([ [(exp(x) - 1)/x, 2*x + y*x, x**x ], [1/x, abs(x), abs(sin(x + 1))]]).limit(x, 0) == \ Matrix([[1, 0, 1], [oo, 0, sin(1)]]) assert a.integrate(x) == Matrix([ [Rational(1, 3)*x**3, y*x**2/2], [x**2*sin(y)/2, x**2*cos(y)/2]]) def test_inv_iszerofunc(): A = eye(4) A.col_swap(0, 1) for method in "GE", "LU": assert A.inv(method=method, iszerofunc=lambda x: x == 0) == \ A.inv(method="ADJ") def test_jacobian_metrics(): rho, phi = symbols("rho,phi") X = Matrix([rho*cos(phi), rho*sin(phi)]) Y = Matrix([rho, phi]) J = X.jacobian(Y) assert J == X.jacobian(Y.T) assert J == (X.T).jacobian(Y) assert J == (X.T).jacobian(Y.T) g = J.T*eye(J.shape[0])*J g = g.applyfunc(trigsimp) assert g == Matrix([[1, 0], [0, rho**2]]) def test_jacobian2(): rho, phi = symbols("rho,phi") X = Matrix([rho*cos(phi), rho*sin(phi), rho**2]) Y = Matrix([rho, phi]) J = Matrix([ [cos(phi), -rho*sin(phi)], [sin(phi), rho*cos(phi)], [ 2*rho, 0], ]) assert X.jacobian(Y) == J def test_issue_4564(): X = Matrix([exp(x + y + z), exp(x + y + z), exp(x + y + z)]) Y = Matrix([x, y, z]) for i in range(1, 3): for j in range(1, 3): X_slice = X[:i, :] Y_slice = Y[:j, :] J = X_slice.jacobian(Y_slice) assert J.rows == i assert J.cols == j for k in range(j): assert J[:, k] == X_slice def test_nonvectorJacobian(): X = Matrix([[exp(x + y + z), exp(x + y + z)], [exp(x + y + z), exp(x + y + z)]]) raises(TypeError, lambda: X.jacobian(Matrix([x, y, z]))) X = X[0, :] Y = Matrix([[x, y], [x, z]]) raises(TypeError, lambda: X.jacobian(Y)) raises(TypeError, lambda: X.jacobian(Matrix([ [x, y], [x, z] ]))) def test_vec(): m = Matrix([[1, 3], [2, 4]]) m_vec = m.vec() assert m_vec.cols == 1 for i in range(4): assert m_vec[i] == i + 1 def test_vech(): m = Matrix([[1, 2], [2, 3]]) m_vech = m.vech() assert m_vech.cols == 1 for i in range(3): assert m_vech[i] == i + 1 m_vech = m.vech(diagonal=False) assert m_vech[0] == 2 m = Matrix([[1, x*(x + y)], [y*x + x**2, 1]]) m_vech = m.vech(diagonal=False) assert m_vech[0] == y*x + x**2 m = Matrix([[1, x*(x + y)], [y*x, 1]]) m_vech = m.vech(diagonal=False, check_symmetry=False) assert m_vech[0] == y*x raises(ShapeError, lambda: Matrix([[1, 3]]).vech()) raises(ValueError, lambda: Matrix([[1, 3], [2, 4]]).vech()) raises(ShapeError, lambda: Matrix([[1, 3]]).vech()) raises(ValueError, lambda: Matrix([[1, 3], [2, 4]]).vech()) def test_diag(): # mostly tested in testcommonmatrix.py assert diag([1, 2, 3]) == Matrix([1, 2, 3]) m = [1, 2, [3]] raises(ValueError, lambda: diag(m)) assert diag(m, strict=False) == Matrix([1, 2, 3]) def test_get_diag_blocks1(): a = Matrix([[1, 2], [2, 3]]) b = Matrix([[3, x], [y, 3]]) c = Matrix([[3, x, 3], [y, 3, z], [x, y, z]]) assert a.get_diag_blocks() == [a] assert b.get_diag_blocks() == [b] assert c.get_diag_blocks() == [c] def test_get_diag_blocks2(): a = Matrix([[1, 2], [2, 3]]) b = Matrix([[3, x], [y, 3]]) c = Matrix([[3, x, 3], [y, 3, z], [x, y, z]]) assert diag(a, b, b).get_diag_blocks() == [a, b, b] assert diag(a, b, c).get_diag_blocks() == [a, b, c] assert diag(a, c, b).get_diag_blocks() == [a, c, b] assert diag(c, c, b).get_diag_blocks() == [c, c, b] def test_inv_block(): a = Matrix([[1, 2], [2, 3]]) b = Matrix([[3, x], [y, 3]]) c = Matrix([[3, x, 3], [y, 3, z], [x, y, z]]) A = diag(a, b, b) assert A.inv(try_block_diag=True) == diag(a.inv(), b.inv(), b.inv()) A = diag(a, b, c) assert A.inv(try_block_diag=True) == diag(a.inv(), b.inv(), c.inv()) A = diag(a, c, b) assert A.inv(try_block_diag=True) == diag(a.inv(), c.inv(), b.inv()) A = diag(a, a, b, a, c, a) assert A.inv(try_block_diag=True) == diag( a.inv(), a.inv(), b.inv(), a.inv(), c.inv(), a.inv()) assert A.inv(try_block_diag=True, method="ADJ") == diag( a.inv(method="ADJ"), a.inv(method="ADJ"), b.inv(method="ADJ"), a.inv(method="ADJ"), c.inv(method="ADJ"), a.inv(method="ADJ")) def test_creation_args(): """ Check that matrix dimensions can be specified using any reasonable type (see issue 4614). """ raises(ValueError, lambda: zeros(3, -1)) raises(TypeError, lambda: zeros(1, 2, 3, 4)) assert zeros(int(3)) == zeros(3) assert zeros(Integer(3)) == zeros(3) raises(ValueError, lambda: zeros(3.)) assert eye(int(3)) == eye(3) assert eye(Integer(3)) == eye(3) raises(ValueError, lambda: eye(3.)) assert ones(int(3), Integer(4)) == ones(3, 4) raises(TypeError, lambda: Matrix(5)) raises(TypeError, lambda: Matrix(1, 2)) raises(ValueError, lambda: Matrix([1, [2]])) def test_diagonal_symmetrical(): m = Matrix(2, 2, [0, 1, 1, 0]) assert not m.is_diagonal() assert m.is_symmetric() assert m.is_symmetric(simplify=False) m = Matrix(2, 2, [1, 0, 0, 1]) assert m.is_diagonal() m = diag(1, 2, 3) assert m.is_diagonal() assert m.is_symmetric() m = Matrix(3, 3, [1, 0, 0, 0, 2, 0, 0, 0, 3]) assert m == diag(1, 2, 3) m = Matrix(2, 3, zeros(2, 3)) assert not m.is_symmetric() assert m.is_diagonal() m = Matrix(((5, 0), (0, 6), (0, 0))) assert m.is_diagonal() m = Matrix(((5, 0, 0), (0, 6, 0))) assert m.is_diagonal() m = Matrix(3, 3, [1, x**2 + 2*x + 1, y, (x + 1)**2, 2, 0, y, 0, 3]) assert m.is_symmetric() assert not m.is_symmetric(simplify=False) assert m.expand().is_symmetric(simplify=False) def test_diagonalization(): m = Matrix([[1, 2+I], [2-I, 3]]) assert m.is_diagonalizable() m = Matrix(3, 2, [-3, 1, -3, 20, 3, 10]) assert not m.is_diagonalizable() assert not m.is_symmetric() raises(NonSquareMatrixError, lambda: m.diagonalize()) # diagonalizable m = diag(1, 2, 3) (P, D) = m.diagonalize() assert P == eye(3) assert D == m m = Matrix(2, 2, [0, 1, 1, 0]) assert m.is_symmetric() assert m.is_diagonalizable() (P, D) = m.diagonalize() assert P.inv() * m * P == D m = Matrix(2, 2, [1, 0, 0, 3]) assert m.is_symmetric() assert m.is_diagonalizable() (P, D) = m.diagonalize() assert P.inv() * m * P == D assert P == eye(2) assert D == m m = Matrix(2, 2, [1, 1, 0, 0]) assert m.is_diagonalizable() (P, D) = m.diagonalize() assert P.inv() * m * P == D m = Matrix(3, 3, [1, 2, 0, 0, 3, 0, 2, -4, 2]) assert m.is_diagonalizable() (P, D) = m.diagonalize() assert P.inv() * m * P == D for i in P: assert i.as_numer_denom()[1] == 1 m = Matrix(2, 2, [1, 0, 0, 0]) assert m.is_diagonal() assert m.is_diagonalizable() (P, D) = m.diagonalize() assert P.inv() * m * P == D assert P == Matrix([[0, 1], [1, 0]]) # diagonalizable, complex only m = Matrix(2, 2, [0, 1, -1, 0]) assert not m.is_diagonalizable(True) raises(MatrixError, lambda: m.diagonalize(True)) assert m.is_diagonalizable() (P, D) = m.diagonalize() assert P.inv() * m * P == D # not diagonalizable m = Matrix(2, 2, [0, 1, 0, 0]) assert not m.is_diagonalizable() raises(MatrixError, lambda: m.diagonalize()) m = Matrix(3, 3, [-3, 1, -3, 20, 3, 10, 2, -2, 4]) assert not m.is_diagonalizable() raises(MatrixError, lambda: m.diagonalize()) # symbolic a, b, c, d = symbols('a b c d') m = Matrix(2, 2, [a, c, c, b]) assert m.is_symmetric() assert m.is_diagonalizable() def test_issue_15887(): # Mutable matrix should not use cache a = MutableDenseMatrix([[0, 1], [1, 0]]) assert a.is_diagonalizable() is True a[1, 0] = 0 assert a.is_diagonalizable() is False a = MutableDenseMatrix([[0, 1], [1, 0]]) a.diagonalize() a[1, 0] = 0 raises(MatrixError, lambda: a.diagonalize()) # Test deprecated cache and kwargs with warns_deprecated_sympy(): a.is_diagonalizable(clear_cache=True) with warns_deprecated_sympy(): a.is_diagonalizable(clear_subproducts=True) def test_jordan_form(): m = Matrix(3, 2, [-3, 1, -3, 20, 3, 10]) raises(NonSquareMatrixError, lambda: m.jordan_form()) # diagonalizable m = Matrix(3, 3, [7, -12, 6, 10, -19, 10, 12, -24, 13]) Jmust = Matrix(3, 3, [-1, 0, 0, 0, 1, 0, 0, 0, 1]) P, J = m.jordan_form() assert Jmust == J assert Jmust == m.diagonalize()[1] # m = Matrix(3, 3, [0, 6, 3, 1, 3, 1, -2, 2, 1]) # m.jordan_form() # very long # m.jordan_form() # # diagonalizable, complex only # Jordan cells # complexity: one of eigenvalues is zero m = Matrix(3, 3, [0, 1, 0, -4, 4, 0, -2, 1, 2]) # The blocks are ordered according to the value of their eigenvalues, # in order to make the matrix compatible with .diagonalize() Jmust = Matrix(3, 3, [2, 1, 0, 0, 2, 0, 0, 0, 2]) P, J = m.jordan_form() assert Jmust == J # complexity: all of eigenvalues are equal m = Matrix(3, 3, [2, 6, -15, 1, 1, -5, 1, 2, -6]) # Jmust = Matrix(3, 3, [-1, 0, 0, 0, -1, 1, 0, 0, -1]) # same here see 1456ff Jmust = Matrix(3, 3, [-1, 1, 0, 0, -1, 0, 0, 0, -1]) P, J = m.jordan_form() assert Jmust == J # complexity: two of eigenvalues are zero m = Matrix(3, 3, [4, -5, 2, 5, -7, 3, 6, -9, 4]) Jmust = Matrix(3, 3, [0, 1, 0, 0, 0, 0, 0, 0, 1]) P, J = m.jordan_form() assert Jmust == J m = Matrix(4, 4, [6, 5, -2, -3, -3, -1, 3, 3, 2, 1, -2, -3, -1, 1, 5, 5]) Jmust = Matrix(4, 4, [2, 1, 0, 0, 0, 2, 0, 0, 0, 0, 2, 1, 0, 0, 0, 2] ) P, J = m.jordan_form() assert Jmust == J m = Matrix(4, 4, [6, 2, -8, -6, -3, 2, 9, 6, 2, -2, -8, -6, -1, 0, 3, 4]) # Jmust = Matrix(4, 4, [2, 0, 0, 0, 0, 2, 1, 0, 0, 0, 2, 0, 0, 0, 0, -2]) # same here see 1456ff Jmust = Matrix(4, 4, [-2, 0, 0, 0, 0, 2, 1, 0, 0, 0, 2, 0, 0, 0, 0, 2]) P, J = m.jordan_form() assert Jmust == J m = Matrix(4, 4, [5, 4, 2, 1, 0, 1, -1, -1, -1, -1, 3, 0, 1, 1, -1, 2]) assert not m.is_diagonalizable() Jmust = Matrix(4, 4, [1, 0, 0, 0, 0, 2, 0, 0, 0, 0, 4, 1, 0, 0, 0, 4]) P, J = m.jordan_form() assert Jmust == J # checking for maximum precision to remain unchanged m = Matrix([[Float('1.0', precision=110), Float('2.0', precision=110)], [Float('3.14159265358979323846264338327', precision=110), Float('4.0', precision=110)]]) P, J = m.jordan_form() for term in J._mat: if isinstance(term, Float): assert term._prec == 110 def test_jordan_form_complex_issue_9274(): A = Matrix([[ 2, 4, 1, 0], [-4, 2, 0, 1], [ 0, 0, 2, 4], [ 0, 0, -4, 2]]) p = 2 - 4*I; q = 2 + 4*I; Jmust1 = Matrix([[p, 1, 0, 0], [0, p, 0, 0], [0, 0, q, 1], [0, 0, 0, q]]) Jmust2 = Matrix([[q, 1, 0, 0], [0, q, 0, 0], [0, 0, p, 1], [0, 0, 0, p]]) P, J = A.jordan_form() assert J == Jmust1 or J == Jmust2 assert simplify(P*J*P.inv()) == A def test_issue_10220(): # two non-orthogonal Jordan blocks with eigenvalue 1 M = Matrix([[1, 0, 0, 1], [0, 1, 1, 0], [0, 0, 1, 1], [0, 0, 0, 1]]) P, J = M.jordan_form() assert P == Matrix([[0, 1, 0, 1], [1, 0, 0, 0], [0, 1, 0, 0], [0, 0, 1, 0]]) assert J == Matrix([ [1, 1, 0, 0], [0, 1, 1, 0], [0, 0, 1, 0], [0, 0, 0, 1]]) def test_jordan_form_issue_15858(): A = Matrix([ [1, 1, 1, 0], [-2, -1, 0, -1], [0, 0, -1, -1], [0, 0, 2, 1]]) (P, J) = A.jordan_form() assert P.expand() == Matrix([ [ -I, -I/2, I, I/2], [-1 + I, 0, -1 - I, 0], [ 0, -S(1)/2 - I/2, 0, -S(1)/2 + I/2], [ 0, 1, 0, 1]]) assert J == Matrix([ [-I, 1, 0, 0], [0, -I, 0, 0], [0, 0, I, 1], [0, 0, 0, I]]) def test_Matrix_berkowitz_charpoly(): UA, K_i, K_w = symbols('UA K_i K_w') A = Matrix([[-K_i - UA + K_i**2/(K_i + K_w), K_i*K_w/(K_i + K_w)], [ K_i*K_w/(K_i + K_w), -K_w + K_w**2/(K_i + K_w)]]) charpoly = A.charpoly(x) assert charpoly == \ Poly(x**2 + (K_i*UA + K_w*UA + 2*K_i*K_w)/(K_i + K_w)*x + K_i*K_w*UA/(K_i + K_w), x, domain='ZZ(K_i,K_w,UA)') assert type(charpoly) is PurePoly A = Matrix([[1, 3], [2, 0]]) assert A.charpoly() == A.charpoly(x) == PurePoly(x**2 - x - 6) A = Matrix([[1, 2], [x, 0]]) p = A.charpoly(x) assert p.gen != x assert p.as_expr().subs(p.gen, x) == x**2 - 3*x def test_exp_jordan_block(): l = Symbol('lamda') m = Matrix.jordan_block(1, l) assert m._eval_matrix_exp_jblock() == Matrix([[exp(l)]]) m = Matrix.jordan_block(3, l) assert m._eval_matrix_exp_jblock() == \ Matrix([ [exp(l), exp(l), exp(l)/2], [0, exp(l), exp(l)], [0, 0, exp(l)]]) def test_exp(): m = Matrix([[3, 4], [0, -2]]) m_exp = Matrix([[exp(3), -4*exp(-2)/5 + 4*exp(3)/5], [0, exp(-2)]]) assert m.exp() == m_exp assert exp(m) == m_exp m = Matrix([[1, 0], [0, 1]]) assert m.exp() == Matrix([[E, 0], [0, E]]) assert exp(m) == Matrix([[E, 0], [0, E]]) m = Matrix([[1, -1], [1, 1]]) assert m.exp() == Matrix([[E*cos(1), -E*sin(1)], [E*sin(1), E*cos(1)]]) def test_log(): l = Symbol('lamda') m = Matrix.jordan_block(1, l) assert m._eval_matrix_log_jblock() == Matrix([[log(l)]]) m = Matrix.jordan_block(4, l) assert m._eval_matrix_log_jblock() == \ Matrix( [ [log(l), 1/l, -1/(2*l**2), 1/(3*l**3)], [0, log(l), 1/l, -1/(2*l**2)], [0, 0, log(l), 1/l], [0, 0, 0, log(l)] ] ) m = Matrix( [[0, 0, 1], [0, 0, 0], [-1, 0, 0]] ) raises(MatrixError, lambda: m.log()) def test_has(): A = Matrix(((x, y), (2, 3))) assert A.has(x) assert not A.has(z) assert A.has(Symbol) A = A.subs(x, 2) assert not A.has(x) def test_find_reasonable_pivot_naive_finds_guaranteed_nonzero1(): # Test if matrices._find_reasonable_pivot_naive() # finds a guaranteed non-zero pivot when the # some of the candidate pivots are symbolic expressions. # Keyword argument: simpfunc=None indicates that no simplifications # should be performed during the search. x = Symbol('x') column = Matrix(3, 1, [x, cos(x)**2 + sin(x)**2, S.Half]) pivot_offset, pivot_val, pivot_assumed_nonzero, simplified =\ _find_reasonable_pivot_naive(column) assert pivot_val == S.Half def test_find_reasonable_pivot_naive_finds_guaranteed_nonzero2(): # Test if matrices._find_reasonable_pivot_naive() # finds a guaranteed non-zero pivot when the # some of the candidate pivots are symbolic expressions. # Keyword argument: simpfunc=_simplify indicates that the search # should attempt to simplify candidate pivots. x = Symbol('x') column = Matrix(3, 1, [x, cos(x)**2+sin(x)**2+x**2, cos(x)**2+sin(x)**2]) pivot_offset, pivot_val, pivot_assumed_nonzero, simplified =\ _find_reasonable_pivot_naive(column, simpfunc=_simplify) assert pivot_val == 1 def test_find_reasonable_pivot_naive_simplifies(): # Test if matrices._find_reasonable_pivot_naive() # simplifies candidate pivots, and reports # their offsets correctly. x = Symbol('x') column = Matrix(3, 1, [x, cos(x)**2+sin(x)**2+x, cos(x)**2+sin(x)**2]) pivot_offset, pivot_val, pivot_assumed_nonzero, simplified =\ _find_reasonable_pivot_naive(column, simpfunc=_simplify) assert len(simplified) == 2 assert simplified[0][0] == 1 assert simplified[0][1] == 1+x assert simplified[1][0] == 2 assert simplified[1][1] == 1 def test_errors(): raises(ValueError, lambda: Matrix([[1, 2], [1]])) raises(IndexError, lambda: Matrix([[1, 2]])[1.2, 5]) raises(IndexError, lambda: Matrix([[1, 2]])[1, 5.2]) raises(ValueError, lambda: randMatrix(3, c=4, symmetric=True)) raises(ValueError, lambda: Matrix([1, 2]).reshape(4, 6)) raises(ShapeError, lambda: Matrix([[1, 2], [3, 4]]).copyin_matrix([1, 0], Matrix([1, 2]))) raises(TypeError, lambda: Matrix([[1, 2], [3, 4]]).copyin_list([0, 1], set())) raises(NonSquareMatrixError, lambda: Matrix([[1, 2, 3], [2, 3, 0]]).inv()) raises(ShapeError, lambda: Matrix(1, 2, [1, 2]).row_join(Matrix([[1, 2], [3, 4]]))) raises( ShapeError, lambda: Matrix([1, 2]).col_join(Matrix([[1, 2], [3, 4]]))) raises(ShapeError, lambda: Matrix([1]).row_insert(1, Matrix([[1, 2], [3, 4]]))) raises(ShapeError, lambda: Matrix([1]).col_insert(1, Matrix([[1, 2], [3, 4]]))) raises(NonSquareMatrixError, lambda: Matrix([1, 2]).trace()) raises(TypeError, lambda: Matrix([1]).applyfunc(1)) raises(ValueError, lambda: Matrix([[1, 2], [3, 4]]).minor(4, 5)) raises(ValueError, lambda: Matrix([[1, 2], [3, 4]]).minor_submatrix(4, 5)) raises(TypeError, lambda: Matrix([1, 2, 3]).cross(1)) raises(TypeError, lambda: Matrix([1, 2, 3]).dot(1)) raises(ShapeError, lambda: Matrix([1, 2, 3]).dot(Matrix([1, 2]))) raises(ShapeError, lambda: Matrix([1, 2]).dot([])) raises(TypeError, lambda: Matrix([1, 2]).dot('a')) with warns_deprecated_sympy(): Matrix([[1, 2], [3, 4]]).dot(Matrix([[4, 3], [1, 2]])) raises(ShapeError, lambda: Matrix([1, 2]).dot([1, 2, 3])) raises(NonSquareMatrixError, lambda: Matrix([1, 2, 3]).exp()) raises(ShapeError, lambda: Matrix([[1, 2], [3, 4]]).normalized()) raises(ValueError, lambda: Matrix([1, 2]).inv(method='not a method')) raises(NonSquareMatrixError, lambda: Matrix([1, 2]).inverse_GE()) raises(ValueError, lambda: Matrix([[1, 2], [1, 2]]).inverse_GE()) raises(NonSquareMatrixError, lambda: Matrix([1, 2]).inverse_ADJ()) raises(ValueError, lambda: Matrix([[1, 2], [1, 2]]).inverse_ADJ()) raises(NonSquareMatrixError, lambda: Matrix([1, 2]).inverse_LU()) raises(NonSquareMatrixError, lambda: Matrix([1, 2]).is_nilpotent()) raises(NonSquareMatrixError, lambda: Matrix([1, 2]).det()) raises(ValueError, lambda: Matrix([[1, 2], [3, 4]]).det(method='Not a real method')) raises(ValueError, lambda: Matrix([[1, 2, 3, 4], [5, 6, 7, 8], [9, 10, 11, 12], [13, 14, 15, 16]]).det(iszerofunc="Not function")) raises(ValueError, lambda: Matrix([[1, 2, 3, 4], [5, 6, 7, 8], [9, 10, 11, 12], [13, 14, 15, 16]]).det(iszerofunc=False)) raises(ValueError, lambda: hessian(Matrix([[1, 2], [3, 4]]), Matrix([[1, 2], [2, 1]]))) raises(ValueError, lambda: hessian(Matrix([[1, 2], [3, 4]]), [])) raises(ValueError, lambda: hessian(Symbol('x')**2, 'a')) raises(IndexError, lambda: eye(3)[5, 2]) raises(IndexError, lambda: eye(3)[2, 5]) M = Matrix(((1, 2, 3, 4), (5, 6, 7, 8), (9, 10, 11, 12), (13, 14, 15, 16))) raises(ValueError, lambda: M.det('method=LU_decomposition()')) V = Matrix([[10, 10, 10]]) M = Matrix([[1, 2, 3], [2, 3, 4], [3, 4, 5]]) raises(ValueError, lambda: M.row_insert(4.7, V)) M = Matrix([[1, 2, 3], [2, 3, 4], [3, 4, 5]]) raises(ValueError, lambda: M.col_insert(-4.2, V)) def test_len(): assert len(Matrix()) == 0 assert len(Matrix([[1, 2]])) == len(Matrix([[1], [2]])) == 2 assert len(Matrix(0, 2, lambda i, j: 0)) == \ len(Matrix(2, 0, lambda i, j: 0)) == 0 assert len(Matrix([[0, 1, 2], [3, 4, 5]])) == 6 assert Matrix([1]) == Matrix([[1]]) assert not Matrix() assert Matrix() == Matrix([]) def test_integrate(): A = Matrix(((1, 4, x), (y, 2, 4), (10, 5, x**2))) assert A.integrate(x) == \ Matrix(((x, 4*x, x**2/2), (x*y, 2*x, 4*x), (10*x, 5*x, x**3/3))) assert A.integrate(y) == \ Matrix(((y, 4*y, x*y), (y**2/2, 2*y, 4*y), (10*y, 5*y, y*x**2))) def test_limit(): A = Matrix(((1, 4, sin(x)/x), (y, 2, 4), (10, 5, x**2 + 1))) assert A.limit(x, 0) == Matrix(((1, 4, 1), (y, 2, 4), (10, 5, 1))) def test_diff(): A = MutableDenseMatrix(((1, 4, x), (y, 2, 4), (10, 5, x**2 + 1))) assert isinstance(A.diff(x), type(A)) assert A.diff(x) == MutableDenseMatrix(((0, 0, 1), (0, 0, 0), (0, 0, 2*x))) assert A.diff(y) == MutableDenseMatrix(((0, 0, 0), (1, 0, 0), (0, 0, 0))) assert diff(A, x) == MutableDenseMatrix(((0, 0, 1), (0, 0, 0), (0, 0, 2*x))) assert diff(A, y) == MutableDenseMatrix(((0, 0, 0), (1, 0, 0), (0, 0, 0))) A_imm = A.as_immutable() assert isinstance(A_imm.diff(x), type(A_imm)) assert A_imm.diff(x) == ImmutableDenseMatrix(((0, 0, 1), (0, 0, 0), (0, 0, 2*x))) assert A_imm.diff(y) == ImmutableDenseMatrix(((0, 0, 0), (1, 0, 0), (0, 0, 0))) assert diff(A_imm, x) == ImmutableDenseMatrix(((0, 0, 1), (0, 0, 0), (0, 0, 2*x))) assert diff(A_imm, y) == ImmutableDenseMatrix(((0, 0, 0), (1, 0, 0), (0, 0, 0))) def test_diff_by_matrix(): # Derive matrix by matrix: A = MutableDenseMatrix([[x, y], [z, t]]) assert A.diff(A) == Array([[[[1, 0], [0, 0]], [[0, 1], [0, 0]]], [[[0, 0], [1, 0]], [[0, 0], [0, 1]]]]) assert diff(A, A) == Array([[[[1, 0], [0, 0]], [[0, 1], [0, 0]]], [[[0, 0], [1, 0]], [[0, 0], [0, 1]]]]) A_imm = A.as_immutable() assert A_imm.diff(A_imm) == Array([[[[1, 0], [0, 0]], [[0, 1], [0, 0]]], [[[0, 0], [1, 0]], [[0, 0], [0, 1]]]]) assert diff(A_imm, A_imm) == Array([[[[1, 0], [0, 0]], [[0, 1], [0, 0]]], [[[0, 0], [1, 0]], [[0, 0], [0, 1]]]]) # Derive a constant matrix: assert A.diff(a) == MutableDenseMatrix([[0, 0], [0, 0]]) B = ImmutableDenseMatrix([a, b]) assert A.diff(B) == Array.zeros(2, 1, 2, 2) assert A.diff(A) == Array([[[[1, 0], [0, 0]], [[0, 1], [0, 0]]], [[[0, 0], [1, 0]], [[0, 0], [0, 1]]]]) # Test diff with tuples: dB = B.diff([[a, b]]) assert dB.shape == (2, 2, 1) assert dB == Array([[[1], [0]], [[0], [1]]]) f = Function("f") fxyz = f(x, y, z) assert fxyz.diff([[x, y, z]]) == Array([fxyz.diff(x), fxyz.diff(y), fxyz.diff(z)]) assert fxyz.diff(([x, y, z], 2)) == Array([ [fxyz.diff(x, 2), fxyz.diff(x, y), fxyz.diff(x, z)], [fxyz.diff(x, y), fxyz.diff(y, 2), fxyz.diff(y, z)], [fxyz.diff(x, z), fxyz.diff(z, y), fxyz.diff(z, 2)], ]) expr = sin(x)*exp(y) assert expr.diff([[x, y]]) == Array([cos(x)*exp(y), sin(x)*exp(y)]) assert expr.diff(y, ((x, y),)) == Array([cos(x)*exp(y), sin(x)*exp(y)]) assert expr.diff(x, ((x, y),)) == Array([-sin(x)*exp(y), cos(x)*exp(y)]) assert expr.diff(((y, x),), [[x, y]]) == Array([[cos(x)*exp(y), -sin(x)*exp(y)], [sin(x)*exp(y), cos(x)*exp(y)]]) # Test different notations: fxyz.diff(x).diff(y).diff(x) == fxyz.diff(((x, y, z),), 3)[0, 1, 0] fxyz.diff(z).diff(y).diff(x) == fxyz.diff(((x, y, z),), 3)[2, 1, 0] fxyz.diff([[x, y, z]], ((z, y, x),)) == Array([[fxyz.diff(i).diff(j) for i in (x, y, z)] for j in (z, y, x)]) # Test scalar derived by matrix remains matrix: res = x.diff(Matrix([[x, y]])) assert isinstance(res, ImmutableDenseMatrix) assert res == Matrix([[1, 0]]) res = (x**3).diff(Matrix([[x, y]])) assert isinstance(res, ImmutableDenseMatrix) assert res == Matrix([[3*x**2, 0]]) def test_getattr(): A = Matrix(((1, 4, x), (y, 2, 4), (10, 5, x**2 + 1))) raises(AttributeError, lambda: A.nonexistantattribute) assert getattr(A, 'diff')(x) == Matrix(((0, 0, 1), (0, 0, 0), (0, 0, 2*x))) def test_hessenberg(): A = Matrix([[3, 4, 1], [2, 4, 5], [0, 1, 2]]) assert A.is_upper_hessenberg A = A.T assert A.is_lower_hessenberg A[0, -1] = 1 assert A.is_lower_hessenberg is False A = Matrix([[3, 4, 1], [2, 4, 5], [3, 1, 2]]) assert not A.is_upper_hessenberg A = zeros(5, 2) assert A.is_upper_hessenberg def test_cholesky(): raises(NonSquareMatrixError, lambda: Matrix((1, 2)).cholesky()) raises(ValueError, lambda: Matrix(((1, 2), (3, 4))).cholesky()) raises(ValueError, lambda: Matrix(((5 + I, 0), (0, 1))).cholesky()) raises(ValueError, lambda: Matrix(((1, 5), (5, 1))).cholesky()) raises(ValueError, lambda: Matrix(((1, 2), (3, 4))).cholesky(hermitian=False)) assert Matrix(((5 + I, 0), (0, 1))).cholesky(hermitian=False) == Matrix([ [sqrt(5 + I), 0], [0, 1]]) A = Matrix(((1, 5), (5, 1))) L = A.cholesky(hermitian=False) assert L == Matrix([[1, 0], [5, 2*sqrt(6)*I]]) assert L*L.T == A A = Matrix(((25, 15, -5), (15, 18, 0), (-5, 0, 11))) L = A.cholesky() assert L * L.T == A assert L.is_lower assert L == Matrix([[5, 0, 0], [3, 3, 0], [-1, 1, 3]]) A = Matrix(((4, -2*I, 2 + 2*I), (2*I, 2, -1 + I), (2 - 2*I, -1 - I, 11))) assert A.cholesky().expand() == Matrix(((2, 0, 0), (I, 1, 0), (1 - I, 0, 3))) raises(NonSquareMatrixError, lambda: SparseMatrix((1, 2)).cholesky()) raises(ValueError, lambda: SparseMatrix(((1, 2), (3, 4))).cholesky()) raises(ValueError, lambda: SparseMatrix(((5 + I, 0), (0, 1))).cholesky()) raises(ValueError, lambda: SparseMatrix(((1, 5), (5, 1))).cholesky()) raises(ValueError, lambda: SparseMatrix(((1, 2), (3, 4))).cholesky(hermitian=False)) assert SparseMatrix(((5 + I, 0), (0, 1))).cholesky(hermitian=False) == Matrix([ [sqrt(5 + I), 0], [0, 1]]) A = SparseMatrix(((1, 5), (5, 1))) L = A.cholesky(hermitian=False) assert L == Matrix([[1, 0], [5, 2*sqrt(6)*I]]) assert L*L.T == A A = SparseMatrix(((25, 15, -5), (15, 18, 0), (-5, 0, 11))) L = A.cholesky() assert L * L.T == A assert L.is_lower assert L == Matrix([[5, 0, 0], [3, 3, 0], [-1, 1, 3]]) A = SparseMatrix(((4, -2*I, 2 + 2*I), (2*I, 2, -1 + I), (2 - 2*I, -1 - I, 11))) assert A.cholesky() == Matrix(((2, 0, 0), (I, 1, 0), (1 - I, 0, 3))) def test_matrix_norm(): # Vector Tests # Test columns and symbols x = Symbol('x', real=True) v = Matrix([cos(x), sin(x)]) assert trigsimp(v.norm(2)) == 1 assert v.norm(10) == Pow(cos(x)**10 + sin(x)**10, Rational(1, 10)) # Test Rows A = Matrix([[5, Rational(3, 2)]]) assert A.norm() == Pow(25 + Rational(9, 4), S.Half) assert A.norm(oo) == max(A._mat) assert A.norm(-oo) == min(A._mat) # Matrix Tests # Intuitive test A = Matrix([[1, 1], [1, 1]]) assert A.norm(2) == 2 assert A.norm(-2) == 0 assert A.norm('frobenius') == 2 assert eye(10).norm(2) == eye(10).norm(-2) == 1 assert A.norm(oo) == 2 # Test with Symbols and more complex entries A = Matrix([[3, y, y], [x, S.Half, -pi]]) assert (A.norm('fro') == sqrt(Rational(37, 4) + 2*abs(y)**2 + pi**2 + x**2)) # Check non-square A = Matrix([[1, 2, -3], [4, 5, Rational(13, 2)]]) assert A.norm(2) == sqrt(Rational(389, 8) + sqrt(78665)/8) assert A.norm(-2) is S.Zero assert A.norm('frobenius') == sqrt(389)/2 # Test properties of matrix norms # https://en.wikipedia.org/wiki/Matrix_norm#Definition # Two matrices A = Matrix([[1, 2], [3, 4]]) B = Matrix([[5, 5], [-2, 2]]) C = Matrix([[0, -I], [I, 0]]) D = Matrix([[1, 0], [0, -1]]) L = [A, B, C, D] alpha = Symbol('alpha', real=True) for order in ['fro', 2, -2]: # Zero Check assert zeros(3).norm(order) is S.Zero # Check Triangle Inequality for all Pairs of Matrices for X in L: for Y in L: dif = (X.norm(order) + Y.norm(order) - (X + Y).norm(order)) assert (dif >= 0) # Scalar multiplication linearity for M in [A, B, C, D]: dif = simplify((alpha*M).norm(order) - abs(alpha) * M.norm(order)) assert dif == 0 # Test Properties of Vector Norms # https://en.wikipedia.org/wiki/Vector_norm # Two column vectors a = Matrix([1, 1 - 1*I, -3]) b = Matrix([S.Half, 1*I, 1]) c = Matrix([-1, -1, -1]) d = Matrix([3, 2, I]) e = Matrix([Integer(1e2), Rational(1, 1e2), 1]) L = [a, b, c, d, e] alpha = Symbol('alpha', real=True) for order in [1, 2, -1, -2, S.Infinity, S.NegativeInfinity, pi]: # Zero Check if order > 0: assert Matrix([0, 0, 0]).norm(order) is S.Zero # Triangle inequality on all pairs if order >= 1: # Triangle InEq holds only for these norms for X in L: for Y in L: dif = (X.norm(order) + Y.norm(order) - (X + Y).norm(order)) assert simplify(dif >= 0) is S.true # Linear to scalar multiplication if order in [1, 2, -1, -2, S.Infinity, S.NegativeInfinity]: for X in L: dif = simplify((alpha*X).norm(order) - (abs(alpha) * X.norm(order))) assert dif == 0 # ord=1 M = Matrix(3, 3, [1, 3, 0, -2, -1, 0, 3, 9, 6]) assert M.norm(1) == 13 def test_condition_number(): x = Symbol('x', real=True) A = eye(3) A[0, 0] = 10 A[2, 2] = Rational(1, 10) assert A.condition_number() == 100 A[1, 1] = x assert A.condition_number() == Max(10, Abs(x)) / Min(Rational(1, 10), Abs(x)) M = Matrix([[cos(x), sin(x)], [-sin(x), cos(x)]]) Mc = M.condition_number() assert all(Float(1.).epsilon_eq(Mc.subs(x, val).evalf()) for val in [Rational(1, 5), S.Half, Rational(1, 10), pi/2, pi, pi*Rational(7, 4) ]) #issue 10782 assert Matrix([]).condition_number() == 0 def test_equality(): A = Matrix(((1, 2, 3), (4, 5, 6), (7, 8, 9))) B = Matrix(((9, 8, 7), (6, 5, 4), (3, 2, 1))) assert A == A[:, :] assert not A != A[:, :] assert not A == B assert A != B assert A != 10 assert not A == 10 # A SparseMatrix can be equal to a Matrix C = SparseMatrix(((1, 0, 0), (0, 1, 0), (0, 0, 1))) D = Matrix(((1, 0, 0), (0, 1, 0), (0, 0, 1))) assert C == D assert not C != D def test_col_join(): assert eye(3).col_join(Matrix([[7, 7, 7]])) == \ Matrix([[1, 0, 0], [0, 1, 0], [0, 0, 1], [7, 7, 7]]) def test_row_insert(): r4 = Matrix([[4, 4, 4]]) for i in range(-4, 5): l = [1, 0, 0] l.insert(i, 4) assert flatten(eye(3).row_insert(i, r4).col(0).tolist()) == l def test_col_insert(): c4 = Matrix([4, 4, 4]) for i in range(-4, 5): l = [0, 0, 0] l.insert(i, 4) assert flatten(zeros(3).col_insert(i, c4).row(0).tolist()) == l def test_normalized(): assert Matrix([3, 4]).normalized() == \ Matrix([Rational(3, 5), Rational(4, 5)]) # Zero vector trivial cases assert Matrix([0, 0, 0]).normalized() == Matrix([0, 0, 0]) # Machine precision error truncation trivial cases m = Matrix([0,0,1.e-100]) assert m.normalized( iszerofunc=lambda x: x.evalf(n=10, chop=True).is_zero ) == Matrix([0, 0, 0]) def test_print_nonzero(): assert capture(lambda: eye(3).print_nonzero()) == \ '[X ]\n[ X ]\n[ X]\n' assert capture(lambda: eye(3).print_nonzero('.')) == \ '[. ]\n[ . ]\n[ .]\n' def test_zeros_eye(): assert Matrix.eye(3) == eye(3) assert Matrix.zeros(3) == zeros(3) assert ones(3, 4) == Matrix(3, 4, [1]*12) i = Matrix([[1, 0], [0, 1]]) z = Matrix([[0, 0], [0, 0]]) for cls in classes: m = cls.eye(2) assert i == m # but m == i will fail if m is immutable assert i == eye(2, cls=cls) assert type(m) == cls m = cls.zeros(2) assert z == m assert z == zeros(2, cls=cls) assert type(m) == cls def test_is_zero(): assert Matrix().is_zero_matrix assert Matrix([[0, 0], [0, 0]]).is_zero_matrix assert zeros(3, 4).is_zero_matrix assert not eye(3).is_zero_matrix assert Matrix([[x, 0], [0, 0]]).is_zero_matrix == None assert SparseMatrix([[x, 0], [0, 0]]).is_zero_matrix == None assert ImmutableMatrix([[x, 0], [0, 0]]).is_zero_matrix == None assert ImmutableSparseMatrix([[x, 0], [0, 0]]).is_zero_matrix == None assert Matrix([[x, 1], [0, 0]]).is_zero_matrix == False a = Symbol('a', nonzero=True) assert Matrix([[a, 0], [0, 0]]).is_zero_matrix == False def test_rotation_matrices(): # This tests the rotation matrices by rotating about an axis and back. theta = pi/3 r3_plus = rot_axis3(theta) r3_minus = rot_axis3(-theta) r2_plus = rot_axis2(theta) r2_minus = rot_axis2(-theta) r1_plus = rot_axis1(theta) r1_minus = rot_axis1(-theta) assert r3_minus*r3_plus*eye(3) == eye(3) assert r2_minus*r2_plus*eye(3) == eye(3) assert r1_minus*r1_plus*eye(3) == eye(3) # Check the correctness of the trace of the rotation matrix assert r1_plus.trace() == 1 + 2*cos(theta) assert r2_plus.trace() == 1 + 2*cos(theta) assert r3_plus.trace() == 1 + 2*cos(theta) # Check that a rotation with zero angle doesn't change anything. assert rot_axis1(0) == eye(3) assert rot_axis2(0) == eye(3) assert rot_axis3(0) == eye(3) def test_DeferredVector(): assert str(DeferredVector("vector")[4]) == "vector[4]" assert sympify(DeferredVector("d")) == DeferredVector("d") raises(IndexError, lambda: DeferredVector("d")[-1]) assert str(DeferredVector("d")) == "d" assert repr(DeferredVector("test")) == "DeferredVector('test')" def test_DeferredVector_not_iterable(): assert not iterable(DeferredVector('X')) def test_DeferredVector_Matrix(): raises(TypeError, lambda: Matrix(DeferredVector("V"))) def test_GramSchmidt(): R = Rational m1 = Matrix(1, 2, [1, 2]) m2 = Matrix(1, 2, [2, 3]) assert GramSchmidt([m1, m2]) == \ [Matrix(1, 2, [1, 2]), Matrix(1, 2, [R(2)/5, R(-1)/5])] assert GramSchmidt([m1.T, m2.T]) == \ [Matrix(2, 1, [1, 2]), Matrix(2, 1, [R(2)/5, R(-1)/5])] # from wikipedia assert GramSchmidt([Matrix([3, 1]), Matrix([2, 2])], True) == [ Matrix([3*sqrt(10)/10, sqrt(10)/10]), Matrix([-sqrt(10)/10, 3*sqrt(10)/10])] # https://github.com/sympy/sympy/issues/9488 L = FiniteSet(Matrix([1])) assert GramSchmidt(L) == [Matrix([[1]])] def test_casoratian(): assert casoratian([1, 2, 3, 4], 1) == 0 assert casoratian([1, 2, 3, 4], 1, zero=False) == 0 def test_zero_dimension_multiply(): assert (Matrix()*zeros(0, 3)).shape == (0, 3) assert zeros(3, 0)*zeros(0, 3) == zeros(3, 3) assert zeros(0, 3)*zeros(3, 0) == Matrix() def test_slice_issue_2884(): m = Matrix(2, 2, range(4)) assert m[1, :] == Matrix([[2, 3]]) assert m[-1, :] == Matrix([[2, 3]]) assert m[:, 1] == Matrix([[1, 3]]).T assert m[:, -1] == Matrix([[1, 3]]).T raises(IndexError, lambda: m[2, :]) raises(IndexError, lambda: m[2, 2]) def test_slice_issue_3401(): assert zeros(0, 3)[:, -1].shape == (0, 1) assert zeros(3, 0)[0, :] == Matrix(1, 0, []) def test_copyin(): s = zeros(3, 3) s[3] = 1 assert s[:, 0] == Matrix([0, 1, 0]) assert s[3] == 1 assert s[3: 4] == [1] s[1, 1] = 42 assert s[1, 1] == 42 assert s[1, 1:] == Matrix([[42, 0]]) s[1, 1:] = Matrix([[5, 6]]) assert s[1, :] == Matrix([[1, 5, 6]]) s[1, 1:] = [[42, 43]] assert s[1, :] == Matrix([[1, 42, 43]]) s[0, 0] = 17 assert s[:, :1] == Matrix([17, 1, 0]) s[0, 0] = [1, 1, 1] assert s[:, 0] == Matrix([1, 1, 1]) s[0, 0] = Matrix([1, 1, 1]) assert s[:, 0] == Matrix([1, 1, 1]) s[0, 0] = SparseMatrix([1, 1, 1]) assert s[:, 0] == Matrix([1, 1, 1]) def test_invertible_check(): # sometimes a singular matrix will have a pivot vector shorter than # the number of rows in a matrix... assert Matrix([[1, 2], [1, 2]]).rref() == (Matrix([[1, 2], [0, 0]]), (0,)) raises(ValueError, lambda: Matrix([[1, 2], [1, 2]]).inv()) m = Matrix([ [-1, -1, 0], [ x, 1, 1], [ 1, x, -1], ]) assert len(m.rref()[1]) != m.rows # in addition, unless simplify=True in the call to rref, the identity # matrix will be returned even though m is not invertible assert m.rref()[0] != eye(3) assert m.rref(simplify=signsimp)[0] != eye(3) raises(ValueError, lambda: m.inv(method="ADJ")) raises(ValueError, lambda: m.inv(method="GE")) raises(ValueError, lambda: m.inv(method="LU")) def test_issue_3959(): x, y = symbols('x, y') e = x*y assert e.subs(x, Matrix([3, 5, 3])) == Matrix([3, 5, 3])*y def test_issue_5964(): assert str(Matrix([[1, 2], [3, 4]])) == 'Matrix([[1, 2], [3, 4]])' def test_issue_7604(): x, y = symbols("x y") assert sstr(Matrix([[x, 2*y], [y**2, x + 3]])) == \ 'Matrix([\n[ x, 2*y],\n[y**2, x + 3]])' def test_is_Identity(): assert eye(3).is_Identity assert eye(3).as_immutable().is_Identity assert not zeros(3).is_Identity assert not ones(3).is_Identity # issue 6242 assert not Matrix([[1, 0, 0]]).is_Identity # issue 8854 assert SparseMatrix(3,3, {(0,0):1, (1,1):1, (2,2):1}).is_Identity assert not SparseMatrix(2,3, range(6)).is_Identity assert not SparseMatrix(3,3, {(0,0):1, (1,1):1}).is_Identity assert not SparseMatrix(3,3, {(0,0):1, (1,1):1, (2,2):1, (0,1):2, (0,2):3}).is_Identity def test_dot(): assert ones(1, 3).dot(ones(3, 1)) == 3 assert ones(1, 3).dot([1, 1, 1]) == 3 assert Matrix([1, 2, 3]).dot(Matrix([1, 2, 3])) == 14 assert Matrix([1, 2, 3*I]).dot(Matrix([I, 2, 3*I])) == -5 + I assert Matrix([1, 2, 3*I]).dot(Matrix([I, 2, 3*I]), hermitian=False) == -5 + I assert Matrix([1, 2, 3*I]).dot(Matrix([I, 2, 3*I]), hermitian=True) == 13 + I assert Matrix([1, 2, 3*I]).dot(Matrix([I, 2, 3*I]), hermitian=True, conjugate_convention="physics") == 13 - I assert Matrix([1, 2, 3*I]).dot(Matrix([4, 5*I, 6]), hermitian=True, conjugate_convention="right") == 4 + 8*I assert Matrix([1, 2, 3*I]).dot(Matrix([4, 5*I, 6]), hermitian=True, conjugate_convention="left") == 4 - 8*I assert Matrix([I, 2*I]).dot(Matrix([I, 2*I]), hermitian=False, conjugate_convention="left") == -5 assert Matrix([I, 2*I]).dot(Matrix([I, 2*I]), conjugate_convention="left") == 5 raises(ValueError, lambda: Matrix([1, 2]).dot(Matrix([3, 4]), hermitian=True, conjugate_convention="test")) def test_dual(): B_x, B_y, B_z, E_x, E_y, E_z = symbols( 'B_x B_y B_z E_x E_y E_z', real=True) F = Matrix(( ( 0, E_x, E_y, E_z), (-E_x, 0, B_z, -B_y), (-E_y, -B_z, 0, B_x), (-E_z, B_y, -B_x, 0) )) Fd = Matrix(( ( 0, -B_x, -B_y, -B_z), (B_x, 0, E_z, -E_y), (B_y, -E_z, 0, E_x), (B_z, E_y, -E_x, 0) )) assert F.dual().equals(Fd) assert eye(3).dual().equals(zeros(3)) assert F.dual().dual().equals(-F) def test_anti_symmetric(): assert Matrix([1, 2]).is_anti_symmetric() is False m = Matrix(3, 3, [0, x**2 + 2*x + 1, y, -(x + 1)**2, 0, x*y, -y, -x*y, 0]) assert m.is_anti_symmetric() is True assert m.is_anti_symmetric(simplify=False) is False assert m.is_anti_symmetric(simplify=lambda x: x) is False # tweak to fail m[2, 1] = -m[2, 1] assert m.is_anti_symmetric() is False # untweak m[2, 1] = -m[2, 1] m = m.expand() assert m.is_anti_symmetric(simplify=False) is True m[0, 0] = 1 assert m.is_anti_symmetric() is False def test_normalize_sort_diogonalization(): A = Matrix(((1, 2), (2, 1))) P, Q = A.diagonalize(normalize=True) assert P*P.T == P.T*P == eye(P.cols) P, Q = A.diagonalize(normalize=True, sort=True) assert P*P.T == P.T*P == eye(P.cols) assert P*Q*P.inv() == A def test_issue_5321(): raises(ValueError, lambda: Matrix([[1, 2, 3], Matrix(0, 1, [])])) def test_issue_5320(): assert Matrix.hstack(eye(2), 2*eye(2)) == Matrix([ [1, 0, 2, 0], [0, 1, 0, 2] ]) assert Matrix.vstack(eye(2), 2*eye(2)) == Matrix([ [1, 0], [0, 1], [2, 0], [0, 2] ]) cls = SparseMatrix assert cls.hstack(cls(eye(2)), cls(2*eye(2))) == Matrix([ [1, 0, 2, 0], [0, 1, 0, 2] ]) def test_issue_11944(): A = Matrix([[1]]) AIm = sympify(A) assert Matrix.hstack(AIm, A) == Matrix([[1, 1]]) assert Matrix.vstack(AIm, A) == Matrix([[1], [1]]) def test_cross(): a = [1, 2, 3] b = [3, 4, 5] col = Matrix([-2, 4, -2]) row = col.T def test(M, ans): assert ans == M assert type(M) == cls for cls in classes: A = cls(a) B = cls(b) test(A.cross(B), col) test(A.cross(B.T), col) test(A.T.cross(B.T), row) test(A.T.cross(B), row) raises(ShapeError, lambda: Matrix(1, 2, [1, 1]).cross(Matrix(1, 2, [1, 1]))) def test_hash(): for cls in classes[-2:]: s = {cls.eye(1), cls.eye(1)} assert len(s) == 1 and s.pop() == cls.eye(1) # issue 3979 for cls in classes[:2]: assert not isinstance(cls.eye(1), Hashable) @XFAIL def test_issue_3979(): # when this passes, delete this and change the [1:2] # to [:2] in the test_hash above for issue 3979 cls = classes[0] raises(AttributeError, lambda: hash(cls.eye(1))) def test_adjoint(): dat = [[0, I], [1, 0]] ans = Matrix([[0, 1], [-I, 0]]) for cls in classes: assert ans == cls(dat).adjoint() def test_simplify_immutable(): from sympy import simplify, sin, cos assert simplify(ImmutableMatrix([[sin(x)**2 + cos(x)**2]])) == \ ImmutableMatrix([[1]]) def test_replace(): from sympy import symbols, Function, Matrix F, G = symbols('F, G', cls=Function) K = Matrix(2, 2, lambda i, j: G(i+j)) M = Matrix(2, 2, lambda i, j: F(i+j)) N = M.replace(F, G) assert N == K def test_replace_map(): from sympy import symbols, Function, Matrix F, G = symbols('F, G', cls=Function) with warns_deprecated_sympy(): K = Matrix(2, 2, [(G(0), {F(0): G(0)}), (G(1), {F(1): G(1)}), (G(1), {F(1): G(1)}), (G(2), {F(2): G(2)})]) M = Matrix(2, 2, lambda i, j: F(i+j)) with warns_deprecated_sympy(): N = M.replace(F, G, True) with warns_deprecated_sympy(): assert N == K def test_atoms(): m = Matrix([[1, 2], [x, 1 - 1/x]]) assert m.atoms() == {S.One,S(2),S.NegativeOne, x} assert m.atoms(Symbol) == {x} def test_pinv(): # Pseudoinverse of an invertible matrix is the inverse. A1 = Matrix([[a, b], [c, d]]) assert simplify(A1.pinv(method="RD")) == simplify(A1.inv()) # Test the four properties of the pseudoinverse for various matrices. As = [Matrix([[13, 104], [2212, 3], [-3, 5]]), Matrix([[1, 7, 9], [11, 17, 19]]), Matrix([a, b])] for A in As: A_pinv = A.pinv(method="RD") AAp = A * A_pinv ApA = A_pinv * A assert simplify(AAp * A) == A assert simplify(ApA * A_pinv) == A_pinv assert AAp.H == AAp assert ApA.H == ApA # XXX Pinv with diagonalization makes expression too complicated. for A in As: A_pinv = simplify(A.pinv(method="ED")) AAp = A * A_pinv ApA = A_pinv * A assert simplify(AAp * A) == A assert simplify(ApA * A_pinv) == A_pinv assert AAp.H == AAp assert ApA.H == ApA # XXX Computing pinv using diagonalization makes an expression that # is too complicated to simplify. # A1 = Matrix([[a, b], [c, d]]) # assert simplify(A1.pinv(method="ED")) == simplify(A1.inv()) # so this is tested numerically at a fixed random point from sympy.core.numbers import comp q = A1.pinv(method="ED") w = A1.inv() reps = {a: -73633, b: 11362, c: 55486, d: 62570} assert all( comp(i.n(), j.n()) for i, j in zip(q.subs(reps), w.subs(reps)) ) @slow @XFAIL def test_pinv_rank_deficient_when_diagonalization_fails(): # Test the four properties of the pseudoinverse for matrices when # diagonalization of A.H*A fails. As = [ Matrix([ [61, 89, 55, 20, 71, 0], [62, 96, 85, 85, 16, 0], [69, 56, 17, 4, 54, 0], [10, 54, 91, 41, 71, 0], [ 7, 30, 10, 48, 90, 0], [0, 0, 0, 0, 0, 0]]) ] for A in As: A_pinv = A.pinv(method="ED") AAp = A * A_pinv ApA = A_pinv * A assert AAp.H == AAp assert ApA.H == ApA def test_issue_7201(): assert ones(0, 1) + ones(0, 1) == Matrix(0, 1, []) assert ones(1, 0) + ones(1, 0) == Matrix(1, 0, []) def test_free_symbols(): for M in ImmutableMatrix, ImmutableSparseMatrix, Matrix, SparseMatrix: assert M([[x], [0]]).free_symbols == {x} def test_from_ndarray(): """See issue 7465.""" try: from numpy import array except ImportError: skip('NumPy must be available to test creating matrices from ndarrays') assert Matrix(array([1, 2, 3])) == Matrix([1, 2, 3]) assert Matrix(array([[1, 2, 3]])) == Matrix([[1, 2, 3]]) assert Matrix(array([[1, 2, 3], [4, 5, 6]])) == \ Matrix([[1, 2, 3], [4, 5, 6]]) assert Matrix(array([x, y, z])) == Matrix([x, y, z]) raises(NotImplementedError, lambda: Matrix(array([[[1, 2], [3, 4]], [[5, 6], [7, 8]]]))) assert Matrix([array([1, 2]), array([3, 4])]) == Matrix([[1, 2], [3, 4]]) assert Matrix([array([1, 2]), [3, 4]]) == Matrix([[1, 2], [3, 4]]) assert Matrix([array([]), array([])]) == Matrix([]) def test_17522_numpy(): from sympy.matrices.common import _matrixify try: from numpy import array, matrix except ImportError: skip('NumPy must be available to test indexing matrixified NumPy ndarrays and matrices') m = _matrixify(array([[1, 2], [3, 4]])) assert m[3] == 4 assert list(m) == [1, 2, 3, 4] m = _matrixify(matrix([[1, 2], [3, 4]])) assert m[3] == 4 assert list(m) == [1, 2, 3, 4] def test_17522_mpmath(): from sympy.matrices.common import _matrixify try: from mpmath import matrix except ImportError: skip('mpmath must be available to test indexing matrixified mpmath matrices') m = _matrixify(matrix([[1, 2], [3, 4]])) assert m[3] == 4 assert list(m) == [1, 2, 3, 4] def test_17522_scipy(): from sympy.matrices.common import _matrixify try: from scipy.sparse import csr_matrix except ImportError: skip('SciPy must be available to test indexing matrixified SciPy sparse matrices') m = _matrixify(csr_matrix([[1, 2], [3, 4]])) assert m[3] == 4 assert list(m) == [1, 2, 3, 4] def test_hermitian(): a = Matrix([[1, I], [-I, 1]]) assert a.is_hermitian a[0, 0] = 2*I assert a.is_hermitian is False a[0, 0] = x assert a.is_hermitian is None a[0, 1] = a[1, 0]*I assert a.is_hermitian is False def test_doit(): a = Matrix([[Add(x,x, evaluate=False)]]) assert a[0] != 2*x assert a.doit() == Matrix([[2*x]]) def test_issue_9457_9467_9876(): # for row_del(index) M = Matrix([[1, 2, 3], [2, 3, 4], [3, 4, 5]]) M.row_del(1) assert M == Matrix([[1, 2, 3], [3, 4, 5]]) N = Matrix([[1, 2, 3], [2, 3, 4], [3, 4, 5]]) N.row_del(-2) assert N == Matrix([[1, 2, 3], [3, 4, 5]]) O = Matrix([[1, 2, 3], [5, 6, 7], [9, 10, 11]]) O.row_del(-1) assert O == Matrix([[1, 2, 3], [5, 6, 7]]) P = Matrix([[1, 2, 3], [2, 3, 4], [3, 4, 5]]) raises(IndexError, lambda: P.row_del(10)) Q = Matrix([[1, 2, 3], [2, 3, 4], [3, 4, 5]]) raises(IndexError, lambda: Q.row_del(-10)) # for col_del(index) M = Matrix([[1, 2, 3], [2, 3, 4], [3, 4, 5]]) M.col_del(1) assert M == Matrix([[1, 3], [2, 4], [3, 5]]) N = Matrix([[1, 2, 3], [2, 3, 4], [3, 4, 5]]) N.col_del(-2) assert N == Matrix([[1, 3], [2, 4], [3, 5]]) P = Matrix([[1, 2, 3], [2, 3, 4], [3, 4, 5]]) raises(IndexError, lambda: P.col_del(10)) Q = Matrix([[1, 2, 3], [2, 3, 4], [3, 4, 5]]) raises(IndexError, lambda: Q.col_del(-10)) def test_issue_9422(): x, y = symbols('x y', commutative=False) a, b = symbols('a b') M = eye(2) M1 = Matrix(2, 2, [x, y, y, z]) assert y*x*M != x*y*M assert b*a*M == a*b*M assert x*M1 != M1*x assert a*M1 == M1*a assert y*x*M == Matrix([[y*x, 0], [0, y*x]]) def test_issue_10770(): M = Matrix([]) a = ['col_insert', 'row_join'], Matrix([9, 6, 3]) b = ['row_insert', 'col_join'], a[1].T c = ['row_insert', 'col_insert'], Matrix([[1, 2], [3, 4]]) for ops, m in (a, b, c): for op in ops: f = getattr(M, op) new = f(m) if 'join' in op else f(42, m) assert new == m and id(new) != id(m) def test_issue_10658(): A = Matrix([[1, 2, 3], [4, 5, 6], [7, 8, 9]]) assert A.extract([0, 1, 2], [True, True, False]) == \ Matrix([[1, 2], [4, 5], [7, 8]]) assert A.extract([0, 1, 2], [True, False, False]) == Matrix([[1], [4], [7]]) assert A.extract([True, False, False], [0, 1, 2]) == Matrix([[1, 2, 3]]) assert A.extract([True, False, True], [0, 1, 2]) == \ Matrix([[1, 2, 3], [7, 8, 9]]) assert A.extract([0, 1, 2], [False, False, False]) == Matrix(3, 0, []) assert A.extract([False, False, False], [0, 1, 2]) == Matrix(0, 3, []) assert A.extract([True, False, True], [False, True, False]) == \ Matrix([[2], [8]]) def test_opportunistic_simplification(): # this test relates to issue #10718, #9480, #11434 # issue #9480 m = Matrix([[-5 + 5*sqrt(2), -5], [-5*sqrt(2)/2 + 5, -5*sqrt(2)/2]]) assert m.rank() == 1 # issue #10781 m = Matrix([[3+3*sqrt(3)*I, -9],[4,-3+3*sqrt(3)*I]]) assert simplify(m.rref()[0] - Matrix([[1, -9/(3 + 3*sqrt(3)*I)], [0, 0]])) == zeros(2, 2) # issue #11434 ax,ay,bx,by,cx,cy,dx,dy,ex,ey,t0,t1 = symbols('a_x a_y b_x b_y c_x c_y d_x d_y e_x e_y t_0 t_1') m = Matrix([[ax,ay,ax*t0,ay*t0,0],[bx,by,bx*t0,by*t0,0],[cx,cy,cx*t0,cy*t0,1],[dx,dy,dx*t0,dy*t0,1],[ex,ey,2*ex*t1-ex*t0,2*ey*t1-ey*t0,0]]) assert m.rank() == 4 def test_partial_pivoting(): # example from https://en.wikipedia.org/wiki/Pivot_element # partial pivoting with back substitution gives a perfect result # naive pivoting give an error ~1e-13, so anything better than # 1e-15 is good mm=Matrix([[0.003 ,59.14, 59.17],[ 5.291, -6.13,46.78]]) assert (mm.rref()[0] - Matrix([[1.0, 0, 10.0], [ 0, 1.0, 1.0]])).norm() < 1e-15 # issue #11549 m_mixed = Matrix([[6e-17, 1.0, 4],[ -1.0, 0, 8],[ 0, 0, 1]]) m_float = Matrix([[6e-17, 1.0, 4.],[ -1.0, 0., 8.],[ 0., 0., 1.]]) m_inv = Matrix([[ 0, -1.0, 8.0],[1.0, 6.0e-17, -4.0],[ 0, 0, 1]]) # this example is numerically unstable and involves a matrix with a norm >= 8, # this comparing the difference of the results with 1e-15 is numerically sound. assert (m_mixed.inv() - m_inv).norm() < 1e-15 assert (m_float.inv() - m_inv).norm() < 1e-15 def test_iszero_substitution(): """ When doing numerical computations, all elements that pass the iszerofunc test should be set to numerically zero if they aren't already. """ # Matrix from issue #9060 m = Matrix([[0.9, -0.1, -0.2, 0],[-0.8, 0.9, -0.4, 0],[-0.1, -0.8, 0.6, 0]]) m_rref = m.rref(iszerofunc=lambda x: abs(x)<6e-15)[0] m_correct = Matrix([[1.0, 0, -0.301369863013699, 0],[ 0, 1.0, -0.712328767123288, 0],[ 0, 0, 0, 0]]) m_diff = m_rref - m_correct assert m_diff.norm() < 1e-15 # if a zero-substitution wasn't made, this entry will be -1.11022302462516e-16 assert m_rref[2,2] == 0 def test_issue_11238(): from sympy import Point xx = 8*tan(pi*Rational(13, 45))/(tan(pi*Rational(13, 45)) + sqrt(3)) yy = (-8*sqrt(3)*tan(pi*Rational(13, 45))**2 + 24*tan(pi*Rational(13, 45)))/(-3 + tan(pi*Rational(13, 45))**2) p1 = Point(0, 0) p2 = Point(1, -sqrt(3)) p0 = Point(xx,yy) m1 = Matrix([p1 - simplify(p0), p2 - simplify(p0)]) m2 = Matrix([p1 - p0, p2 - p0]) m3 = Matrix([simplify(p1 - p0), simplify(p2 - p0)]) # This system has expressions which are zero and # cannot be easily proved to be such, so without # numerical testing, these assertions will fail. Z = lambda x: abs(x.n()) < 1e-20 assert m1.rank(simplify=True, iszerofunc=Z) == 1 assert m2.rank(simplify=True, iszerofunc=Z) == 1 assert m3.rank(simplify=True, iszerofunc=Z) == 1 def test_as_real_imag(): m1 = Matrix(2,2,[1,2,3,4]) m2 = m1*S.ImaginaryUnit m3 = m1 + m2 for kls in classes: a,b = kls(m3).as_real_imag() assert list(a) == list(m1) assert list(b) == list(m1) def test_deprecated(): # Maintain tests for deprecated functions. We must capture # the deprecation warnings. When the deprecated functionality is # removed, the corresponding tests should be removed. m = Matrix(3, 3, [0, 1, 0, -4, 4, 0, -2, 1, 2]) P, Jcells = m.jordan_cells() assert Jcells[1] == Matrix(1, 1, [2]) assert Jcells[0] == Matrix(2, 2, [2, 1, 0, 2]) with warns_deprecated_sympy(): assert Matrix([[1,2],[3,4]]).dot(Matrix([[1,3],[4,5]])) == [10, 19, 14, 28] def test_issue_14489(): from sympy import Mod A = Matrix([-1, 1, 2]) B = Matrix([10, 20, -15]) assert Mod(A, 3) == Matrix([2, 1, 2]) assert Mod(B, 4) == Matrix([2, 0, 1]) def test_issue_14943(): # Test that __array__ accepts the optional dtype argument try: from numpy import array except ImportError: skip('NumPy must be available to test creating matrices from ndarrays') M = Matrix([[1,2], [3,4]]) assert array(M, dtype=float).dtype.name == 'float64' def test_case_6913(): m = MatrixSymbol('m', 1, 1) a = Symbol("a") a = m[0, 0]>0 assert str(a) == 'm[0, 0] > 0' def test_issue_11948(): A = MatrixSymbol('A', 3, 3) a = Wild('a') assert A.match(a) == {a: A} def test_gramschmidt_conjugate_dot(): vecs = [Matrix([1, I]), Matrix([1, -I])] assert Matrix.orthogonalize(*vecs) == \ [Matrix([[1], [I]]), Matrix([[1], [-I]])] vecs = [Matrix([1, I, 0]), Matrix([I, 0, -I])] assert Matrix.orthogonalize(*vecs) == \ [Matrix([[1], [I], [0]]), Matrix([[I/2], [S(1)/2], [-I]])] mat = Matrix([[1, I], [1, -I]]) Q, R = mat.QRdecomposition() assert Q * Q.H == Matrix.eye(2) def test_issue_8207(): a = Matrix(MatrixSymbol('a', 3, 1)) b = Matrix(MatrixSymbol('b', 3, 1)) c = a.dot(b) d = diff(c, a[0, 0]) e = diff(d, a[0, 0]) assert d == b[0, 0] assert e == 0 def test_func(): from sympy.simplify.simplify import nthroot A = Matrix([[1, 2],[0, 3]]) assert A.analytic_func(sin(x*t), x) == Matrix([[sin(t), sin(3*t) - sin(t)], [0, sin(3*t)]]) A = Matrix([[2, 1],[1, 2]]) assert (pi * A / 6).analytic_func(cos(x), x) == Matrix([[sqrt(3)/4, -sqrt(3)/4], [-sqrt(3)/4, sqrt(3)/4]]) raises(ValueError, lambda : zeros(5).analytic_func(log(x), x)) raises(ValueError, lambda : (A*x).analytic_func(log(x), x)) A = Matrix([[0, -1, -2, 3], [0, -1, -2, 3], [0, 1, 0, -1], [0, 0, -1, 1]]) assert A.analytic_func(exp(x), x) == A.exp() raises(ValueError, lambda : A.analytic_func(sqrt(x), x)) A = Matrix([[41, 12],[12, 34]]) assert simplify(A.analytic_func(sqrt(x), x)**2) == A A = Matrix([[3, -12, 4], [-1, 0, -2], [-1, 5, -1]]) assert simplify(A.analytic_func(nthroot(x, 3), x)**3) == A A = Matrix([[2, 0, 0, 0], [1, 2, 0, 0], [0, 1, 3, 0], [0, 0, 1, 3]]) assert A.analytic_func(exp(x), x) == A.exp() A = Matrix([[0, 2, 1, 6], [0, 0, 1, 2], [0, 0, 0, 3], [0, 0, 0, 0]]) assert A.analytic_func(exp(x*t), x) == expand(simplify((A*t).exp())) def test_issue_19809(): def f(): assert _dotprodsimp_state.state == None m = Matrix([[1]]) m = m * m return True with dotprodsimp(True): with concurrent.futures.ThreadPoolExecutor() as executor: future = executor.submit(f) assert future.result()
98f2824c49994345f8553febd88c30bafcba5b7ba9982f04b9f44abe979ae2aa
from sympy import (S, Dummy, Lambda, symbols, Interval, Intersection, Set, EmptySet, FiniteSet, Union, ComplexRegion, Mul) from sympy.multipledispatch import dispatch from sympy.sets.conditionset import ConditionSet from sympy.sets.fancysets import (Integers, Naturals, Reals, Range, ImageSet, Rationals) from sympy.sets.sets import UniversalSet, imageset, ProductSet @dispatch(ConditionSet, ConditionSet) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 return None @dispatch(ConditionSet, Set) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 return ConditionSet(a.sym, a.condition, Intersection(a.base_set, b)) @dispatch(Naturals, Integers) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 return a @dispatch(Naturals, Naturals) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 return a if a is S.Naturals else b @dispatch(Interval, Naturals) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 return intersection_sets(b, a) @dispatch(ComplexRegion, Set) # type: ignore # noqa:F811 def intersection_sets(self, other): # noqa:F811 if other.is_ComplexRegion: # self in rectangular form if (not self.polar) and (not other.polar): return ComplexRegion(Intersection(self.sets, other.sets)) # self in polar form elif self.polar and other.polar: r1, theta1 = self.a_interval, self.b_interval r2, theta2 = other.a_interval, other.b_interval new_r_interval = Intersection(r1, r2) new_theta_interval = Intersection(theta1, theta2) # 0 and 2*Pi means the same if ((2*S.Pi in theta1 and S.Zero in theta2) or (2*S.Pi in theta2 and S.Zero in theta1)): new_theta_interval = Union(new_theta_interval, FiniteSet(0)) return ComplexRegion(new_r_interval*new_theta_interval, polar=True) if other.is_subset(S.Reals): new_interval = [] x = symbols("x", cls=Dummy, real=True) # self in rectangular form if not self.polar: for element in self.psets: if S.Zero in element.args[1]: new_interval.append(element.args[0]) new_interval = Union(*new_interval) return Intersection(new_interval, other) # self in polar form elif self.polar: for element in self.psets: if S.Zero in element.args[1]: new_interval.append(element.args[0]) if S.Pi in element.args[1]: new_interval.append(ImageSet(Lambda(x, -x), element.args[0])) if S.Zero in element.args[0]: new_interval.append(FiniteSet(0)) new_interval = Union(*new_interval) return Intersection(new_interval, other) @dispatch(Integers, Reals) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 return a @dispatch(Range, Interval) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 from sympy.functions.elementary.integers import floor, ceiling if not all(i.is_number for i in b.args[:2]): return # In case of null Range, return an EmptySet. if a.size == 0: return S.EmptySet # trim down to self's size, and represent # as a Range with step 1. start = ceiling(max(b.inf, a.inf)) if start not in b: start += 1 end = floor(min(b.sup, a.sup)) if end not in b: end -= 1 return intersection_sets(a, Range(start, end + 1)) @dispatch(Range, Naturals) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 return intersection_sets(a, Interval(b.inf, S.Infinity)) @dispatch(Range, Range) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 from sympy.solvers.diophantine.diophantine import diop_linear from sympy.core.numbers import ilcm from sympy import sign # non-overlap quick exits if not b: return S.EmptySet if not a: return S.EmptySet if b.sup < a.inf: return S.EmptySet if b.inf > a.sup: return S.EmptySet # work with finite end at the start r1 = a if r1.start.is_infinite: r1 = r1.reversed r2 = b if r2.start.is_infinite: r2 = r2.reversed # If both ends are infinite then it means that one Range is just the set # of all integers (the step must be 1). if r1.start.is_infinite: return b if r2.start.is_infinite: return a # this equation represents the values of the Range; # it's a linear equation eq = lambda r, i: r.start + i*r.step # we want to know when the two equations might # have integer solutions so we use the diophantine # solver va, vb = diop_linear(eq(r1, Dummy('a')) - eq(r2, Dummy('b'))) # check for no solution no_solution = va is None and vb is None if no_solution: return S.EmptySet # there is a solution # ------------------- # find the coincident point, c a0 = va.as_coeff_Add()[0] c = eq(r1, a0) # find the first point, if possible, in each range # since c may not be that point def _first_finite_point(r1, c): if c == r1.start: return c # st is the signed step we need to take to # get from c to r1.start st = sign(r1.start - c)*step # use Range to calculate the first point: # we want to get as close as possible to # r1.start; the Range will not be null since # it will at least contain c s1 = Range(c, r1.start + st, st)[-1] if s1 == r1.start: pass else: # if we didn't hit r1.start then, if the # sign of st didn't match the sign of r1.step # we are off by one and s1 is not in r1 if sign(r1.step) != sign(st): s1 -= st if s1 not in r1: return return s1 # calculate the step size of the new Range step = abs(ilcm(r1.step, r2.step)) s1 = _first_finite_point(r1, c) if s1 is None: return S.EmptySet s2 = _first_finite_point(r2, c) if s2 is None: return S.EmptySet # replace the corresponding start or stop in # the original Ranges with these points; the # result must have at least one point since # we know that s1 and s2 are in the Ranges def _updated_range(r, first): st = sign(r.step)*step if r.start.is_finite: rv = Range(first, r.stop, st) else: rv = Range(r.start, first + st, st) return rv r1 = _updated_range(a, s1) r2 = _updated_range(b, s2) # work with them both in the increasing direction if sign(r1.step) < 0: r1 = r1.reversed if sign(r2.step) < 0: r2 = r2.reversed # return clipped Range with positive step; it # can't be empty at this point start = max(r1.start, r2.start) stop = min(r1.stop, r2.stop) return Range(start, stop, step) @dispatch(Range, Integers) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 return a @dispatch(ImageSet, Set) # type: ignore # noqa:F811 def intersection_sets(self, other): # noqa:F811 from sympy.solvers.diophantine import diophantine # Only handle the straight-forward univariate case if (len(self.lamda.variables) > 1 or self.lamda.signature != self.lamda.variables): return None base_set = self.base_sets[0] # Intersection between ImageSets with Integers as base set # For {f(n) : n in Integers} & {g(m) : m in Integers} we solve the # diophantine equations f(n)=g(m). # If the solutions for n are {h(t) : t in Integers} then we return # {f(h(t)) : t in integers}. # If the solutions for n are {n_1, n_2, ..., n_k} then we return # {f(n_i) : 1 <= i <= k}. if base_set is S.Integers: gm = None if isinstance(other, ImageSet) and other.base_sets == (S.Integers,): gm = other.lamda.expr var = other.lamda.variables[0] # Symbol of second ImageSet lambda must be distinct from first m = Dummy('m') gm = gm.subs(var, m) elif other is S.Integers: m = gm = Dummy('m') if gm is not None: fn = self.lamda.expr n = self.lamda.variables[0] try: solns = list(diophantine(fn - gm, syms=(n, m), permute=True)) except (TypeError, NotImplementedError): # TypeError if equation not polynomial with rational coeff. # NotImplementedError if correct format but no solver. return # 3 cases are possible for solns: # - empty set, # - one or more parametric (infinite) solutions, # - a finite number of (non-parametric) solution couples. # Among those, there is one type of solution set that is # not helpful here: multiple parametric solutions. if len(solns) == 0: return EmptySet elif any(not isinstance(s, int) and s.free_symbols for tupl in solns for s in tupl): if len(solns) == 1: soln, solm = solns[0] (t,) = soln.free_symbols expr = fn.subs(n, soln.subs(t, n)).expand() return imageset(Lambda(n, expr), S.Integers) else: return else: return FiniteSet(*(fn.subs(n, s[0]) for s in solns)) if other == S.Reals: from sympy.core.function import expand_complex from sympy.solvers.solvers import denoms, solve_linear from sympy.core.relational import Eq f = self.lamda.expr n = self.lamda.variables[0] n_ = Dummy(n.name, real=True) f_ = f.subs(n, n_) re, im = f_.as_real_imag() im = expand_complex(im) re = re.subs(n_, n) im = im.subs(n_, n) ifree = im.free_symbols lam = Lambda(n, re) if im.is_zero: # allow re-evaluation # of self in this case to make # the result canonical pass elif im.is_zero is False: return S.EmptySet elif ifree != {n}: return None else: # univarite imaginary part in same variable x, xis = zip(*[solve_linear(i, 0) for i in Mul.make_args(im) if n in i.free_symbols]) if x and all(i == n for i in x): base_set -= FiniteSet(xis) else: base_set -= ConditionSet(n, Eq(im, 0), S.Integers) # exclude values that make denominators 0 for i in denoms(f): if i.has(n): sol = list(zip(*[solve_linear(i, 0) for i in Mul.make_args(im) if n in i.free_symbols])) if sol != []: x, xis = sol if x and all(i == n for i in x): base_set -= FiniteSet(xis) else: base_set -= ConditionSet(n, Eq(i, 0), S.Integers) return imageset(lam, base_set) elif isinstance(other, Interval): from sympy.solvers.solveset import (invert_real, invert_complex, solveset) f = self.lamda.expr n = self.lamda.variables[0] new_inf, new_sup = None, None new_lopen, new_ropen = other.left_open, other.right_open if f.is_real: inverter = invert_real else: inverter = invert_complex g1, h1 = inverter(f, other.inf, n) g2, h2 = inverter(f, other.sup, n) if all(isinstance(i, FiniteSet) for i in (h1, h2)): if g1 == n: if len(h1) == 1: new_inf = h1.args[0] if g2 == n: if len(h2) == 1: new_sup = h2.args[0] # TODO: Design a technique to handle multiple-inverse # functions # Any of the new boundary values cannot be determined if any(i is None for i in (new_sup, new_inf)): return range_set = S.EmptySet if all(i.is_real for i in (new_sup, new_inf)): # this assumes continuity of underlying function # however fixes the case when it is decreasing if new_inf > new_sup: new_inf, new_sup = new_sup, new_inf new_interval = Interval(new_inf, new_sup, new_lopen, new_ropen) range_set = base_set.intersect(new_interval) else: if other.is_subset(S.Reals): solutions = solveset(f, n, S.Reals) if not isinstance(range_set, (ImageSet, ConditionSet)): range_set = solutions.intersect(other) else: return if range_set is S.EmptySet: return S.EmptySet elif isinstance(range_set, Range) and range_set.size is not S.Infinity: range_set = FiniteSet(*list(range_set)) if range_set is not None: return imageset(Lambda(n, f), range_set) return else: return @dispatch(ProductSet, ProductSet) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 if len(b.args) != len(a.args): return S.EmptySet return ProductSet(*(i.intersect(j) for i, j in zip(a.sets, b.sets))) @dispatch(Interval, Interval) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 # handle (-oo, oo) infty = S.NegativeInfinity, S.Infinity if a == Interval(*infty): l, r = a.left, a.right if l.is_real or l in infty or r.is_real or r in infty: return b # We can't intersect [0,3] with [x,6] -- we don't know if x>0 or x<0 if not a._is_comparable(b): return None empty = False if a.start <= b.end and b.start <= a.end: # Get topology right. if a.start < b.start: start = b.start left_open = b.left_open elif a.start > b.start: start = a.start left_open = a.left_open else: start = a.start left_open = a.left_open or b.left_open if a.end < b.end: end = a.end right_open = a.right_open elif a.end > b.end: end = b.end right_open = b.right_open else: end = a.end right_open = a.right_open or b.right_open if end - start == 0 and (left_open or right_open): empty = True else: empty = True if empty: return S.EmptySet return Interval(start, end, left_open, right_open) @dispatch(type(EmptySet), Set) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 return S.EmptySet @dispatch(UniversalSet, Set) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 return b @dispatch(FiniteSet, FiniteSet) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 return FiniteSet(*(a._elements & b._elements)) @dispatch(FiniteSet, Set) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 try: return FiniteSet(*[el for el in a if el in b]) except TypeError: return None # could not evaluate `el in b` due to symbolic ranges. @dispatch(Set, Set) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 return None @dispatch(Integers, Rationals) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 return a @dispatch(Naturals, Rationals) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 return a @dispatch(Rationals, Reals) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 return a def _intlike_interval(a, b): try: from sympy.functions.elementary.integers import floor, ceiling if b._inf is S.NegativeInfinity and b._sup is S.Infinity: return a s = Range(max(a.inf, ceiling(b.left)), floor(b.right) + 1) return intersection_sets(s, b) # take out endpoints if open interval except ValueError: return None @dispatch(Integers, Interval) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 return _intlike_interval(a, b) @dispatch(Naturals, Interval) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 return _intlike_interval(a, b)
b456eb903fab77041ce0b3d48128b1545e877d90f0a124c290be9ffc56d76251
from sympy.core.expr import unchanged from sympy.sets import (ConditionSet, Intersection, FiniteSet, EmptySet, Union, Contains, ImageSet) from sympy import (Symbol, Eq, Ne, S, Abs, sin, asin, pi, Interval, And, Mod, oo, Function, Lambda, symbols, Matrix, MatrixSymbol) from sympy.testing.pytest import raises, warns_deprecated_sympy w = Symbol('w') x = Symbol('x') y = Symbol('y') z = Symbol('z') f = Function('f') def test_CondSet(): sin_sols_principal = ConditionSet(x, Eq(sin(x), 0), Interval(0, 2*pi, False, True)) assert pi in sin_sols_principal assert pi/2 not in sin_sols_principal assert 3*pi not in sin_sols_principal assert oo not in sin_sols_principal assert 5 in ConditionSet(x, x**2 > 4, S.Reals) assert 1 not in ConditionSet(x, x**2 > 4, S.Reals) # in this case, 0 is not part of the base set so # it can't be in any subset selected by the condition assert 0 not in ConditionSet(x, y > 5, Interval(1, 7)) # since 'in' requires a true/false, the following raises # an error because the given value provides no information # for the condition to evaluate (since the condition does # not depend on the dummy symbol): the result is `y > 5`. # In this case, ConditionSet is just acting like # Piecewise((Interval(1, 7), y > 5), (S.EmptySet, True)). raises(TypeError, lambda: 6 in ConditionSet(x, y > 5, Interval(1, 7))) X = MatrixSymbol('X', 2, 2) matrix_set = ConditionSet(X, Eq(X*Matrix([[1, 1], [1, 1]]), X)) Y = Matrix([[0, 0], [0, 0]]) assert matrix_set.contains(Y).doit() is S.true Z = Matrix([[1, 2], [3, 4]]) assert matrix_set.contains(Z).doit() is S.false assert isinstance(ConditionSet(x, x < 1, {x, y}).base_set, FiniteSet) raises(TypeError, lambda: ConditionSet(x, x + 1, {x, y})) raises(TypeError, lambda: ConditionSet(x, x, 1)) I = S.Integers U = S.UniversalSet C = ConditionSet assert C(x, False, I) is S.EmptySet assert C(x, True, I) is I assert C(x, x < 1, C(x, x < 2, I) ) == C(x, (x < 1) & (x < 2), I) assert C(y, y < 1, C(x, y < 2, I) ) == C(x, (x < 1) & (y < 2), I), C(y, y < 1, C(x, y < 2, I)) assert C(y, y < 1, C(x, x < 2, I) ) == C(y, (y < 1) & (y < 2), I) assert C(y, y < 1, C(x, y < x, I) ) == C(x, (x < 1) & (y < x), I) assert unchanged(C, y, x < 1, C(x, y < x, I)) assert ConditionSet(x, x < 1).base_set is U # arg checking is not done at instantiation but this # will raise an error when containment is tested assert ConditionSet((x,), x < 1).base_set is U c = ConditionSet((x, y), x < y, I**2) assert (1, 2) in c assert (1, pi) not in c raises(TypeError, lambda: C(x, x > 1, C((x, y), x > 1, I**2))) # signature mismatch since only 3 args are accepted raises(TypeError, lambda: C((x, y), x + y < 2, U, U)) def test_CondSet_intersect(): input_conditionset = ConditionSet(x, x**2 > 4, Interval(1, 4, False, False)) other_domain = Interval(0, 3, False, False) output_conditionset = ConditionSet(x, x**2 > 4, Interval( 1, 3, False, False)) assert Intersection(input_conditionset, other_domain ) == output_conditionset def test_issue_9849(): assert ConditionSet(x, Eq(x, x), S.Naturals ) is S.Naturals assert ConditionSet(x, Eq(Abs(sin(x)), -1), S.Naturals ) == S.EmptySet def test_simplified_FiniteSet_in_CondSet(): assert ConditionSet(x, And(x < 1, x > -3), FiniteSet(0, 1, 2) ) == FiniteSet(0) assert ConditionSet(x, x < 0, FiniteSet(0, 1, 2)) == EmptySet assert ConditionSet(x, And(x < -3), EmptySet) == EmptySet y = Symbol('y') assert (ConditionSet(x, And(x > 0), FiniteSet(-1, 0, 1, y)) == Union(FiniteSet(1), ConditionSet(x, And(x > 0), FiniteSet(y)))) assert (ConditionSet(x, Eq(Mod(x, 3), 1), FiniteSet(1, 4, 2, y)) == Union(FiniteSet(1, 4), ConditionSet(x, Eq(Mod(x, 3), 1), FiniteSet(y)))) def test_free_symbols(): assert ConditionSet(x, Eq(y, 0), FiniteSet(z) ).free_symbols == {y, z} assert ConditionSet(x, Eq(x, 0), FiniteSet(z) ).free_symbols == {z} assert ConditionSet(x, Eq(x, 0), FiniteSet(x, z) ).free_symbols == {x, z} assert ConditionSet(x, Eq(x, 0), ImageSet(Lambda(y, y**2), S.Integers)).free_symbols == set() def test_bound_symbols(): assert ConditionSet(x, Eq(y, 0), FiniteSet(z) ).bound_symbols == [x] assert ConditionSet(x, Eq(x, 0), FiniteSet(x, y) ).bound_symbols == [x] assert ConditionSet(x, x < 10, ImageSet(Lambda(y, y**2), S.Integers) ).bound_symbols == [x] assert ConditionSet(x, x < 10, ConditionSet(y, y > 1, S.Integers) ).bound_symbols == [x] def test_as_dummy(): _0, _1 = symbols('_0 _1') assert ConditionSet(x, x < 1, Interval(y, oo) ).as_dummy() == ConditionSet(_0, _0 < 1, Interval(y, oo)) assert ConditionSet(x, x < 1, Interval(x, oo) ).as_dummy() == ConditionSet(_0, _0 < 1, Interval(x, oo)) assert ConditionSet(x, x < 1, ImageSet(Lambda(y, y**2), S.Integers) ).as_dummy() == ConditionSet( _0, _0 < 1, ImageSet(Lambda(_0, _0**2), S.Integers)) e = ConditionSet((x, y), x <= y, S.Reals**2) assert e.bound_symbols == [x, y] assert e.as_dummy() == ConditionSet((_0, _1), _0 <= _1, S.Reals**2) assert e.as_dummy() == ConditionSet((y, x), y <= x, S.Reals**2 ).as_dummy() def test_subs_CondSet(): s = FiniteSet(z, y) c = ConditionSet(x, x < 2, s) assert c.subs(x, y) == c assert c.subs(z, y) == ConditionSet(x, x < 2, FiniteSet(y)) assert c.xreplace({x: y}) == ConditionSet(y, y < 2, s) assert ConditionSet(x, x < y, s ).subs(y, w) == ConditionSet(x, x < w, s.subs(y, w)) # if the user uses assumptions that cause the condition # to evaluate, that can't be helped from SymPy's end n = Symbol('n', negative=True) assert ConditionSet(n, 0 < n, S.Integers) is S.EmptySet p = Symbol('p', positive=True) assert ConditionSet(n, n < y, S.Integers ).subs(n, x) == ConditionSet(n, n < y, S.Integers) raises(ValueError, lambda: ConditionSet( x + 1, x < 1, S.Integers)) assert ConditionSet( p, n < x, Interval(-5, 5)).subs(x, p) == Interval(-5, 5), ConditionSet( p, n < x, Interval(-5, 5)).subs(x, p) assert ConditionSet( n, n < x, Interval(-oo, 0)).subs(x, p ) == Interval(-oo, 0) assert ConditionSet(f(x), f(x) < 1, {w, z} ).subs(f(x), y) == ConditionSet(f(x), f(x) < 1, {w, z}) # issue 17341 k = Symbol('k') img1 = ImageSet(Lambda(k, 2*k*pi + asin(y)), S.Integers) img2 = ImageSet(Lambda(k, 2*k*pi + asin(S.One/3)), S.Integers) assert ConditionSet(x, Contains( y, Interval(-1,1)), img1).subs(y, S.One/3).dummy_eq(img2) assert (0, 1) in ConditionSet((x, y), x + y < 3, S.Integers**2) raises(TypeError, lambda: ConditionSet(n, n < -10, Interval(0, 10))) def test_subs_CondSet_tebr(): with warns_deprecated_sympy(): assert ConditionSet((x, y), {x + 1, x + y}, S.Reals**2) == \ ConditionSet((x, y), Eq(x + 1, 0) & Eq(x + y, 0), S.Reals**2) def test_dummy_eq(): C = ConditionSet I = S.Integers c = C(x, x < 1, I) assert c.dummy_eq(C(y, y < 1, I)) assert c.dummy_eq(1) == False assert c.dummy_eq(C(x, x < 1, S.Reals)) == False c1 = ConditionSet((x, y), Eq(x + 1, 0) & Eq(x + y, 0), S.Reals**2) c2 = ConditionSet((x, y), Eq(x + 1, 0) & Eq(x + y, 0), S.Reals**2) c3 = ConditionSet((x, y), Eq(x + 1, 0) & Eq(x + y, 0), S.Complexes**2) assert c1.dummy_eq(c2) assert c1.dummy_eq(c3) is False assert c.dummy_eq(c1) is False assert c1.dummy_eq(c) is False # issue 19496 m = Symbol('m') n = Symbol('n') a = Symbol('a') d1 = ImageSet(Lambda(m, m*pi), S.Integers) d2 = ImageSet(Lambda(n, n*pi), S.Integers) c1 = ConditionSet(x, Ne(a, 0), d1) c2 = ConditionSet(x, Ne(a, 0), d2) assert c1.dummy_eq(c2) def test_contains(): assert 6 in ConditionSet(x, x > 5, Interval(1, 7)) assert (8 in ConditionSet(x, y > 5, Interval(1, 7))) is False # `in` should give True or False; in this case there is not # enough information for that result raises(TypeError, lambda: 6 in ConditionSet(x, y > 5, Interval(1, 7))) # here, there is enough information but the comparison is # not defined raises(TypeError, lambda: 0 in ConditionSet(x, 1/x >= 0, S.Reals)) assert ConditionSet(x, y > 5, Interval(1, 7) ).contains(6) == (y > 5) assert ConditionSet(x, y > 5, Interval(1, 7) ).contains(8) is S.false assert ConditionSet(x, y > 5, Interval(1, 7) ).contains(w) == And(Contains(w, Interval(1, 7)), y > 5) # This returns an unevaluated Contains object # because 1/0 should not be defined for 1 and 0 in the context of # reals. assert ConditionSet(x, 1/x >= 0, S.Reals).contains(0) == \ Contains(0, ConditionSet(x, 1/x >= 0, S.Reals), evaluate=False) c = ConditionSet((x, y), x + y > 1, S.Integers**2) assert not c.contains(1) assert c.contains((2, 1)) assert not c.contains((0, 1)) c = ConditionSet((w, (x, y)), w + x + y > 1, S.Integers*S.Integers**2) assert not c.contains(1) assert not c.contains((1, 2)) assert not c.contains(((1, 2), 3)) assert not c.contains(((1, 2), (3, 4))) assert c.contains((1, (3, 4))) def test_as_relational(): assert ConditionSet((x, y), x > 1, S.Integers**2).as_relational((x, y) ) == (x > 1) & Contains((x, y), S.Integers**2) assert ConditionSet(x, x > 1, S.Integers).as_relational(x ) == Contains(x, S.Integers) & (x > 1) def test_flatten(): """Tests whether there is basic denesting functionality""" inner = ConditionSet(x, sin(x) + x > 0) outer = ConditionSet(x, Contains(x, inner), S.Reals) assert outer == ConditionSet(x, sin(x) + x > 0, S.Reals) inner = ConditionSet(y, sin(y) + y > 0) outer = ConditionSet(x, Contains(y, inner), S.Reals) assert outer != ConditionSet(x, sin(x) + x > 0, S.Reals) inner = ConditionSet(x, sin(x) + x > 0).intersect(Interval(-1, 1)) outer = ConditionSet(x, Contains(x, inner), S.Reals) assert outer == ConditionSet(x, sin(x) + x > 0, Interval(-1, 1)) def test_duplicate(): from sympy.core.function import BadSignatureError # test coverage for line 95 in conditionset.py, check for duplicates in symbols dup = symbols('a,a') raises(BadSignatureError, lambda: ConditionSet(dup, x < 0))
9dfbbb4ab2cd600b6ff49c743555f7bf8c1173c7e67223c98871f604d625d75e
from sympy.core.expr import unchanged from sympy.core.singleton import S from sympy.core.symbol import Symbol from sympy.sets.contains import Contains from sympy.sets.fancysets import Interval from sympy.sets.powerset import PowerSet from sympy.sets.sets import FiniteSet from sympy.testing.pytest import raises, XFAIL def test_powerset_creation(): assert unchanged(PowerSet, FiniteSet(1, 2)) assert unchanged(PowerSet, S.EmptySet) raises(ValueError, lambda: PowerSet(123)) assert unchanged(PowerSet, S.Reals) assert unchanged(PowerSet, S.Integers) def test_powerset_rewrite_FiniteSet(): assert PowerSet(FiniteSet(1, 2)).rewrite(FiniteSet) == \ FiniteSet(S.EmptySet, FiniteSet(1), FiniteSet(2), FiniteSet(1, 2)) assert PowerSet(S.EmptySet).rewrite(FiniteSet) == FiniteSet(S.EmptySet) assert PowerSet(S.Naturals).rewrite(FiniteSet) == PowerSet(S.Naturals) def test_finiteset_rewrite_powerset(): assert FiniteSet(S.EmptySet).rewrite(PowerSet) == PowerSet(S.EmptySet) assert FiniteSet( S.EmptySet, FiniteSet(1), FiniteSet(2), FiniteSet(1, 2)).rewrite(PowerSet) == \ PowerSet(FiniteSet(1, 2)) assert FiniteSet(1, 2, 3).rewrite(PowerSet) == FiniteSet(1, 2, 3) def test_powerset__contains__(): subset_series = [ S.EmptySet, FiniteSet(1, 2), S.Naturals, S.Naturals0, S.Integers, S.Rationals, S.Reals, S.Complexes] l = len(subset_series) for i in range(l): for j in range(l): if i <= j: assert subset_series[i] in \ PowerSet(subset_series[j], evaluate=False) else: assert subset_series[i] not in \ PowerSet(subset_series[j], evaluate=False) @XFAIL def test_failing_powerset__contains__(): # XXX These are failing when evaluate=True, # but using unevaluated PowerSet works fine. assert FiniteSet(1, 2) not in PowerSet(S.EmptySet).rewrite(FiniteSet) assert S.Naturals not in PowerSet(S.EmptySet).rewrite(FiniteSet) assert S.Naturals not in PowerSet(FiniteSet(1, 2)).rewrite(FiniteSet) assert S.Naturals0 not in PowerSet(S.EmptySet).rewrite(FiniteSet) assert S.Naturals0 not in PowerSet(FiniteSet(1, 2)).rewrite(FiniteSet) assert S.Integers not in PowerSet(S.EmptySet).rewrite(FiniteSet) assert S.Integers not in PowerSet(FiniteSet(1, 2)).rewrite(FiniteSet) assert S.Rationals not in PowerSet(S.EmptySet).rewrite(FiniteSet) assert S.Rationals not in PowerSet(FiniteSet(1, 2)).rewrite(FiniteSet) assert S.Reals not in PowerSet(S.EmptySet).rewrite(FiniteSet) assert S.Reals not in PowerSet(FiniteSet(1, 2)).rewrite(FiniteSet) assert S.Complexes not in PowerSet(S.EmptySet).rewrite(FiniteSet) assert S.Complexes not in PowerSet(FiniteSet(1, 2)).rewrite(FiniteSet) def test_powerset__len__(): A = PowerSet(S.EmptySet, evaluate=False) assert len(A) == 1 A = PowerSet(A, evaluate=False) assert len(A) == 2 A = PowerSet(A, evaluate=False) assert len(A) == 4 A = PowerSet(A, evaluate=False) assert len(A) == 16 def test_powerset__iter__(): a = PowerSet(FiniteSet(1, 2)).__iter__() assert next(a) == S.EmptySet assert next(a) == FiniteSet(1) assert next(a) == FiniteSet(2) assert next(a) == FiniteSet(1, 2) a = PowerSet(S.Naturals).__iter__() assert next(a) == S.EmptySet assert next(a) == FiniteSet(1) assert next(a) == FiniteSet(2) assert next(a) == FiniteSet(1, 2) assert next(a) == FiniteSet(3) assert next(a) == FiniteSet(1, 3) assert next(a) == FiniteSet(2, 3) assert next(a) == FiniteSet(1, 2, 3) def test_powerset_contains(): A = PowerSet(FiniteSet(1), evaluate=False) assert A.contains(2) == Contains(2, A) x = Symbol('x') A = PowerSet(FiniteSet(x), evaluate=False) assert A.contains(FiniteSet(1)) == Contains(FiniteSet(1), A) def test_powerset_method(): # EmptySet A = FiniteSet() pset = A.powerset() assert len(pset) == 1 assert pset == FiniteSet(S.EmptySet) # FiniteSets A = FiniteSet(1, 2) pset = A.powerset() assert len(pset) == 2**len(A) assert pset == FiniteSet(FiniteSet(), FiniteSet(1), FiniteSet(2), A) # Not finite sets A = Interval(0, 1) assert A.powerset() == PowerSet(A) def test_is_subset(): # covers line 101-102 # initalize powerset(1), which is a subset of powerset(1,2) subset = PowerSet(FiniteSet(1)) pset = PowerSet(FiniteSet(1, 2)) bad_set = PowerSet(FiniteSet(2, 3)) # assert "subset" is subset of pset == True assert subset.is_subset(pset) # assert "bad_set" is subset of pset == False assert not pset.is_subset(bad_set)
92bb1c064b3892c45bab31818649b0b74f3927a44382b7e0caa4af2542a47601
from sympy import Symbol, Contains, S, Interval, FiniteSet, oo, Eq from sympy.core.expr import unchanged from sympy.testing.pytest import raises def test_contains_basic(): raises(TypeError, lambda: Contains(S.Integers, 1)) assert Contains(2, S.Integers) is S.true assert Contains(-2, S.Naturals) is S.false i = Symbol('i', integer=True) assert Contains(i, S.Naturals) == Contains(i, S.Naturals, evaluate=False) def test_issue_6194(): x = Symbol('x') assert unchanged(Contains, x, Interval(0, 1)) assert Interval(0, 1).contains(x) == (S.Zero <= x) & (x <= 1) assert Contains(x, FiniteSet(0)) != S.false assert Contains(x, Interval(1, 1)) != S.false assert Contains(x, S.Integers) != S.false def test_issue_10326(): assert Contains(oo, Interval(-oo, oo)) == False assert Contains(-oo, Interval(-oo, oo)) == False def test_binary_symbols(): x = Symbol('x') y = Symbol('y') z = Symbol('z') assert Contains(x, FiniteSet(y, Eq(z, True)) ).binary_symbols == {y, z} def test_as_set(): x = Symbol('x') y = Symbol('y') # Contains is a BooleanFunction whose value depends on an arg's # containment in a Set -- rewriting as a Set is not yet implemented raises(NotImplementedError, lambda: Contains(x, FiniteSet(y)).as_set()) def test_type_error(): # Pass in a parameter not of type "set" raises(TypeError, lambda: Contains(2, None))
c66145f7df6ab8fb67dfe5d0395482ce5dc4ddc334e1a21bb0a2147e4845c691
from sympy.sets.ordinals import Ordinal, OmegaPower, ord0, omega from sympy.testing.pytest import raises def test_string_ordinals(): assert str(omega) == 'w' assert str(Ordinal(OmegaPower(5, 3), OmegaPower(3, 2))) == 'w**5*3 + w**3*2' assert str(Ordinal(OmegaPower(5, 3), OmegaPower(0, 5))) == 'w**5*3 + 5' assert str(Ordinal(OmegaPower(1, 3), OmegaPower(0, 5))) == 'w*3 + 5' assert str(Ordinal(OmegaPower(omega + 1 ,1), OmegaPower(3, 2))) == 'w**(w + 1) + w**3*2' def test_addition_with_integers(): assert 3 + Ordinal(OmegaPower(5, 3)) == Ordinal(OmegaPower(5, 3)) assert Ordinal(OmegaPower(5, 3))+3 == Ordinal(OmegaPower(5, 3), OmegaPower(0, 3)) assert Ordinal(OmegaPower(5, 3), OmegaPower(0, 2))+3 == \ Ordinal(OmegaPower(5, 3), OmegaPower(0, 5)) def test_addition_with_ordinals(): assert Ordinal(OmegaPower(5, 3), OmegaPower(3, 2)) + Ordinal(OmegaPower(3, 3)) == \ Ordinal(OmegaPower(5, 3), OmegaPower(3, 5)) assert Ordinal(OmegaPower(5, 3), OmegaPower(3, 2)) + Ordinal(OmegaPower(4, 2)) == \ Ordinal(OmegaPower(5, 3), OmegaPower(4, 2)) assert Ordinal(OmegaPower(omega, 2), OmegaPower(3, 2)) + Ordinal(OmegaPower(4, 2)) == \ Ordinal(OmegaPower(omega, 2), OmegaPower(4, 2)) def test_comparison(): assert Ordinal(OmegaPower(5, 3)) > Ordinal(OmegaPower(4, 3), OmegaPower(2, 1)) assert Ordinal(OmegaPower(5, 3), OmegaPower(3, 2)) < Ordinal(OmegaPower(5, 4)) assert Ordinal(OmegaPower(5, 4)) < Ordinal(OmegaPower(5, 5), OmegaPower(4, 1)) assert Ordinal(OmegaPower(5, 3), OmegaPower(3, 2)) == \ Ordinal(OmegaPower(5, 3), OmegaPower(3, 2)) assert not Ordinal(OmegaPower(5, 3), OmegaPower(3, 2)) == Ordinal(OmegaPower(5, 3)) assert Ordinal(OmegaPower(omega, 3)) > Ordinal(OmegaPower(5, 3)) def test_multiplication_with_integers(): w = omega assert 3*w == w assert w*9 == Ordinal(OmegaPower(1, 9)) def test_multiplication(): w = omega assert w*(w + 1) == w*w + w assert (w + 1)*(w + 1) == w*w + w + 1 assert w*1 == w assert 1*w == w assert w*ord0 == ord0 assert ord0*w == ord0 assert w**w == w * w**w assert (w**w)*w*w == w**(w + 2) def test_exponentiation(): w = omega assert w**2 == w*w assert w**3 == w*w*w assert w**(w + 1) == Ordinal(OmegaPower(omega + 1, 1)) assert (w**w)*(w**w) == w**(w*2) def test_comapre_not_instance(): w = OmegaPower(omega + 1, 1) assert(not (w == None)) assert(not (w < 5)) raises(TypeError, lambda: w < 6.66) def test_is_successort(): w = Ordinal(OmegaPower(5, 1)) assert not w.is_successor_ordinal
c9e295f505af0383b24aefd1bb7f6f1bdee7138d34bc3da4940493e8dbe194ce
from sympy.core.expr import unchanged from sympy.sets.fancysets import (ImageSet, Range, normalize_theta_set, ComplexRegion) from sympy.sets.sets import (Complement, FiniteSet, Interval, Union, imageset, Intersection, ProductSet, Contains) from sympy.simplify.simplify import simplify from sympy import (S, Symbol, Lambda, symbols, cos, sin, pi, oo, Basic, Rational, sqrt, tan, log, exp, Abs, I, Tuple, eye, Dummy, floor, And, Eq) from sympy.utilities.iterables import cartes from sympy.testing.pytest import XFAIL, raises from sympy.abc import x, y, t, z from sympy.core.mod import Mod import itertools def test_naturals(): N = S.Naturals assert 5 in N assert -5 not in N assert 5.5 not in N ni = iter(N) a, b, c, d = next(ni), next(ni), next(ni), next(ni) assert (a, b, c, d) == (1, 2, 3, 4) assert isinstance(a, Basic) assert N.intersect(Interval(-5, 5)) == Range(1, 6) assert N.intersect(Interval(-5, 5, True, True)) == Range(1, 5) assert N.boundary == N assert N.is_open == False assert N.is_closed == True assert N.inf == 1 assert N.sup is oo assert not N.contains(oo) for s in (S.Naturals0, S.Naturals): assert s.intersection(S.Reals) is s assert s.is_subset(S.Reals) assert N.as_relational(x) == And(Eq(floor(x), x), x >= 1, x < oo) def test_naturals0(): N = S.Naturals0 assert 0 in N assert -1 not in N assert next(iter(N)) == 0 assert not N.contains(oo) assert N.contains(sin(x)) == Contains(sin(x), N) def test_integers(): Z = S.Integers assert 5 in Z assert -5 in Z assert 5.5 not in Z assert not Z.contains(oo) assert not Z.contains(-oo) zi = iter(Z) a, b, c, d = next(zi), next(zi), next(zi), next(zi) assert (a, b, c, d) == (0, 1, -1, 2) assert isinstance(a, Basic) assert Z.intersect(Interval(-5, 5)) == Range(-5, 6) assert Z.intersect(Interval(-5, 5, True, True)) == Range(-4, 5) assert Z.intersect(Interval(5, S.Infinity)) == Range(5, S.Infinity) assert Z.intersect(Interval.Lopen(5, S.Infinity)) == Range(6, S.Infinity) assert Z.inf is -oo assert Z.sup is oo assert Z.boundary == Z assert Z.is_open == False assert Z.is_closed == True assert Z.as_relational(x) == And(Eq(floor(x), x), -oo < x, x < oo) def test_ImageSet(): raises(ValueError, lambda: ImageSet(x, S.Integers)) assert ImageSet(Lambda(x, 1), S.Integers) == FiniteSet(1) assert ImageSet(Lambda(x, y), S.Integers) == {y} assert ImageSet(Lambda(x, 1), S.EmptySet) == S.EmptySet empty = Intersection(FiniteSet(log(2)/pi), S.Integers) assert unchanged(ImageSet, Lambda(x, 1), empty) # issue #17471 squares = ImageSet(Lambda(x, x**2), S.Naturals) assert 4 in squares assert 5 not in squares assert FiniteSet(*range(10)).intersect(squares) == FiniteSet(1, 4, 9) assert 16 not in squares.intersect(Interval(0, 10)) si = iter(squares) a, b, c, d = next(si), next(si), next(si), next(si) assert (a, b, c, d) == (1, 4, 9, 16) harmonics = ImageSet(Lambda(x, 1/x), S.Naturals) assert Rational(1, 5) in harmonics assert Rational(.25) in harmonics assert 0.25 not in harmonics assert Rational(.3) not in harmonics assert (1, 2) not in harmonics assert harmonics.is_iterable assert imageset(x, -x, Interval(0, 1)) == Interval(-1, 0) assert ImageSet(Lambda(x, x**2), Interval(0, 2)).doit() == Interval(0, 4) assert ImageSet(Lambda((x, y), 2*x), {4}, {3}).doit() == FiniteSet(8) assert (ImageSet(Lambda((x, y), x+y), {1, 2, 3}, {10, 20, 30}).doit() == FiniteSet(11, 12, 13, 21, 22, 23, 31, 32, 33)) c = Interval(1, 3) * Interval(1, 3) assert Tuple(2, 6) in ImageSet(Lambda(((x, y),), (x, 2*y)), c) assert Tuple(2, S.Half) in ImageSet(Lambda(((x, y),), (x, 1/y)), c) assert Tuple(2, -2) not in ImageSet(Lambda(((x, y),), (x, y**2)), c) assert Tuple(2, -2) in ImageSet(Lambda(((x, y),), (x, -2)), c) c3 = ProductSet(Interval(3, 7), Interval(8, 11), Interval(5, 9)) assert Tuple(8, 3, 9) in ImageSet(Lambda(((t, y, x),), (y, t, x)), c3) assert Tuple(Rational(1, 8), 3, 9) in ImageSet(Lambda(((t, y, x),), (1/y, t, x)), c3) assert 2/pi not in ImageSet(Lambda(((x, y),), 2/x), c) assert 2/S(100) not in ImageSet(Lambda(((x, y),), 2/x), c) assert Rational(2, 3) in ImageSet(Lambda(((x, y),), 2/x), c) S1 = imageset(lambda x, y: x + y, S.Integers, S.Naturals) assert S1.base_pset == ProductSet(S.Integers, S.Naturals) assert S1.base_sets == (S.Integers, S.Naturals) # Passing a set instead of a FiniteSet shouldn't raise assert unchanged(ImageSet, Lambda(x, x**2), {1, 2, 3}) S2 = ImageSet(Lambda(((x, y),), x+y), {(1, 2), (3, 4)}) assert 3 in S2.doit() # FIXME: This doesn't yet work: #assert 3 in S2 assert S2._contains(3) is None raises(TypeError, lambda: ImageSet(Lambda(x, x**2), 1)) def test_image_is_ImageSet(): assert isinstance(imageset(x, sqrt(sin(x)), Range(5)), ImageSet) def test_halfcircle(): r, th = symbols('r, theta', real=True) L = Lambda(((r, th),), (r*cos(th), r*sin(th))) halfcircle = ImageSet(L, Interval(0, 1)*Interval(0, pi)) assert (1, 0) in halfcircle assert (0, -1) not in halfcircle assert (0, 0) in halfcircle assert halfcircle._contains((r, 0)) is None # This one doesn't work: #assert (r, 2*pi) not in halfcircle assert not halfcircle.is_iterable def test_ImageSet_iterator_not_injective(): L = Lambda(x, x - x % 2) # produces 0, 2, 2, 4, 4, 6, 6, ... evens = ImageSet(L, S.Naturals) i = iter(evens) # No repeats here assert (next(i), next(i), next(i), next(i)) == (0, 2, 4, 6) def test_inf_Range_len(): raises(ValueError, lambda: len(Range(0, oo, 2))) assert Range(0, oo, 2).size is S.Infinity assert Range(0, -oo, -2).size is S.Infinity assert Range(oo, 0, -2).size is S.Infinity assert Range(-oo, 0, 2).size is S.Infinity def test_Range_set(): empty = Range(0) assert Range(5) == Range(0, 5) == Range(0, 5, 1) r = Range(10, 20, 2) assert 12 in r assert 8 not in r assert 11 not in r assert 30 not in r assert list(Range(0, 5)) == list(range(5)) assert list(Range(5, 0, -1)) == list(range(5, 0, -1)) assert Range(5, 15).sup == 14 assert Range(5, 15).inf == 5 assert Range(15, 5, -1).sup == 15 assert Range(15, 5, -1).inf == 6 assert Range(10, 67, 10).sup == 60 assert Range(60, 7, -10).inf == 10 assert len(Range(10, 38, 10)) == 3 assert Range(0, 0, 5) == empty assert Range(oo, oo, 1) == empty assert Range(oo, 1, 1) == empty assert Range(-oo, 1, -1) == empty assert Range(1, oo, -1) == empty assert Range(1, -oo, 1) == empty assert Range(1, -4, oo) == empty ip = symbols('ip', positive=True) assert Range(0, ip, -1) == empty assert Range(0, -ip, 1) == empty assert Range(1, -4, -oo) == Range(1, 2) assert Range(1, 4, oo) == Range(1, 2) assert Range(-oo, oo).size == oo assert Range(oo, -oo, -1).size == oo raises(ValueError, lambda: Range(-oo, oo, 2)) raises(ValueError, lambda: Range(x, pi, y)) raises(ValueError, lambda: Range(x, y, 0)) assert 5 in Range(0, oo, 5) assert -5 in Range(-oo, 0, 5) assert oo not in Range(0, oo) ni = symbols('ni', integer=False) assert ni not in Range(oo) u = symbols('u', integer=None) assert Range(oo).contains(u) is not False inf = symbols('inf', infinite=True) assert inf not in Range(-oo, oo) raises(ValueError, lambda: Range(0, oo, 2)[-1]) raises(ValueError, lambda: Range(0, -oo, -2)[-1]) assert Range(-oo, 1, 1)[-1] is S.Zero assert Range(oo, 1, -1)[-1] == 2 assert inf not in Range(oo) assert Range(1, 10, 1)[-1] == 9 assert all(i.is_Integer for i in Range(0, -1, 1)) it = iter(Range(-oo, 0, 2)) raises(TypeError, lambda: next(it)) assert empty.intersect(S.Integers) == empty assert Range(-1, 10, 1).intersect(S.Integers) == Range(-1, 10, 1) assert Range(-1, 10, 1).intersect(S.Naturals) == Range(1, 10, 1) assert Range(-1, 10, 1).intersect(S.Naturals0) == Range(0, 10, 1) # test slicing assert Range(1, 10, 1)[5] == 6 assert Range(1, 12, 2)[5] == 11 assert Range(1, 10, 1)[-1] == 9 assert Range(1, 10, 3)[-1] == 7 raises(ValueError, lambda: Range(oo,0,-1)[1:3:0]) raises(ValueError, lambda: Range(oo,0,-1)[:1]) raises(ValueError, lambda: Range(1, oo)[-2]) raises(ValueError, lambda: Range(-oo, 1)[2]) raises(IndexError, lambda: Range(10)[-20]) raises(IndexError, lambda: Range(10)[20]) raises(ValueError, lambda: Range(2, -oo, -2)[2:2:0]) assert Range(2, -oo, -2)[2:2:2] == empty assert Range(2, -oo, -2)[:2:2] == Range(2, -2, -4) raises(ValueError, lambda: Range(-oo, 4, 2)[:2:2]) assert Range(-oo, 4, 2)[::-2] == Range(2, -oo, -4) raises(ValueError, lambda: Range(-oo, 4, 2)[::2]) assert Range(oo, 2, -2)[::] == Range(oo, 2, -2) assert Range(-oo, 4, 2)[:-2:-2] == Range(2, 0, -4) assert Range(-oo, 4, 2)[:-2:2] == Range(-oo, 0, 4) raises(ValueError, lambda: Range(-oo, 4, 2)[:0:-2]) raises(ValueError, lambda: Range(-oo, 4, 2)[:2:-2]) assert Range(-oo, 4, 2)[-2::-2] == Range(0, -oo, -4) raises(ValueError, lambda: Range(-oo, 4, 2)[-2:0:-2]) raises(ValueError, lambda: Range(-oo, 4, 2)[0::2]) assert Range(oo, 2, -2)[0::] == Range(oo, 2, -2) raises(ValueError, lambda: Range(-oo, 4, 2)[0:-2:2]) assert Range(oo, 2, -2)[0:-2:] == Range(oo, 6, -2) raises(ValueError, lambda: Range(oo, 2, -2)[0:2:]) raises(ValueError, lambda: Range(-oo, 4, 2)[2::-1]) assert Range(-oo, 4, 2)[-2::2] == Range(0, 4, 4) assert Range(oo, 0, -2)[-10:0:2] == empty raises(ValueError, lambda: Range(oo, 0, -2)[0]) raises(ValueError, lambda: Range(oo, 0, -2)[-10:10:2]) raises(ValueError, lambda: Range(oo, 0, -2)[0::-2]) assert Range(oo, 0, -2)[0:-4:-2] == empty assert Range(oo, 0, -2)[:0:2] == empty raises(ValueError, lambda: Range(oo, 0, -2)[:1:-1]) # test empty Range assert Range(x, x, y) == empty assert empty.reversed == empty assert 0 not in empty assert list(empty) == [] assert len(empty) == 0 assert empty.size is S.Zero assert empty.intersect(FiniteSet(0)) is S.EmptySet assert bool(empty) is False raises(IndexError, lambda: empty[0]) assert empty[:0] == empty raises(NotImplementedError, lambda: empty.inf) raises(NotImplementedError, lambda: empty.sup) assert empty.as_relational(x) is S.false AB = [None] + list(range(12)) for R in [ Range(1, 10), Range(1, 10, 2), ]: r = list(R) for a, b, c in cartes(AB, AB, [-3, -1, None, 1, 3]): for reverse in range(2): r = list(reversed(r)) R = R.reversed result = list(R[a:b:c]) ans = r[a:b:c] txt = ('\n%s[%s:%s:%s] = %s -> %s' % ( R, a, b, c, result, ans)) check = ans == result assert check, txt assert Range(1, 10, 1).boundary == Range(1, 10, 1) for r in (Range(1, 10, 2), Range(1, oo, 2)): rev = r.reversed assert r.inf == rev.inf and r.sup == rev.sup assert r.step == -rev.step builtin_range = range raises(TypeError, lambda: Range(builtin_range(1))) assert S(builtin_range(10)) == Range(10) assert S(builtin_range(1000000000000)) == Range(1000000000000) # test Range.as_relational assert Range(1, 4).as_relational(x) == (x >= 1) & (x <= 3) & Eq(Mod(x, 1), 0) assert Range(oo, 1, -2).as_relational(x) == (x >= 3) & (x < oo) & Eq(Mod(x + 1, -2), 0) def test_Range_symbolic(): # symbolic Range xr = Range(x, x + 4, 5) sr = Range(x, y, t) i = Symbol('i', integer=True) ip = Symbol('i', integer=True, positive=True) ipr = Range(ip) inr = Range(0, -ip, -1) ir = Range(i, i + 19, 2) ir2 = Range(i, i*8, 3*i) i = Symbol('i', integer=True) inf = symbols('inf', infinite=True) raises(ValueError, lambda: Range(inf)) raises(ValueError, lambda: Range(inf, 0, -1)) raises(ValueError, lambda: Range(inf, inf, 1)) raises(ValueError, lambda: Range(1, 1, inf)) # args assert xr.args == (x, x + 5, 5) assert sr.args == (x, y, t) assert ir.args == (i, i + 20, 2) assert ir2.args == (i, 10*i, 3*i) # reversed raises(ValueError, lambda: xr.reversed) raises(ValueError, lambda: sr.reversed) assert ipr.reversed.args == (ip - 1, -1, -1) assert inr.reversed.args == (-ip + 1, 1, 1) assert ir.reversed.args == (i + 18, i - 2, -2) assert ir2.reversed.args == (7*i, -2*i, -3*i) # contains assert inf not in sr assert inf not in ir assert 0 in ipr assert 0 in inr raises(TypeError, lambda: 1 in ipr) raises(TypeError, lambda: -1 in inr) assert .1 not in sr assert .1 not in ir assert i + 1 not in ir assert i + 2 in ir raises(TypeError, lambda: x in xr) # XXX is this what contains is supposed to do? raises(TypeError, lambda: 1 in sr) # XXX is this what contains is supposed to do? # iter raises(ValueError, lambda: next(iter(xr))) raises(ValueError, lambda: next(iter(sr))) assert next(iter(ir)) == i assert next(iter(ir2)) == i assert sr.intersect(S.Integers) == sr assert sr.intersect(FiniteSet(x)) == Intersection({x}, sr) raises(ValueError, lambda: sr[:2]) raises(ValueError, lambda: xr[0]) raises(ValueError, lambda: sr[0]) # len assert len(ir) == ir.size == 10 assert len(ir2) == ir2.size == 3 raises(ValueError, lambda: len(xr)) raises(ValueError, lambda: xr.size) raises(ValueError, lambda: len(sr)) raises(ValueError, lambda: sr.size) # bool assert bool(Range(0)) == False assert bool(xr) assert bool(ir) assert bool(ipr) assert bool(inr) raises(ValueError, lambda: bool(sr)) raises(ValueError, lambda: bool(ir2)) # inf raises(ValueError, lambda: xr.inf) raises(ValueError, lambda: sr.inf) assert ipr.inf == 0 assert inr.inf == -ip + 1 assert ir.inf == i raises(ValueError, lambda: ir2.inf) # sup raises(ValueError, lambda: xr.sup) raises(ValueError, lambda: sr.sup) assert ipr.sup == ip - 1 assert inr.sup == 0 assert ir.inf == i raises(ValueError, lambda: ir2.sup) # getitem raises(ValueError, lambda: xr[0]) raises(ValueError, lambda: sr[0]) raises(ValueError, lambda: sr[-1]) raises(ValueError, lambda: sr[:2]) assert ir[:2] == Range(i, i + 4, 2) assert ir[0] == i assert ir[-2] == i + 16 assert ir[-1] == i + 18 assert ir2[:2] == Range(i, 7*i, 3*i) assert ir2[0] == i assert ir2[-2] == 4*i assert ir2[-1] == 7*i raises(ValueError, lambda: Range(i)[-1]) assert ipr[0] == ipr.inf == 0 assert ipr[-1] == ipr.sup == ip - 1 assert inr[0] == inr.sup == 0 assert inr[-1] == inr.inf == -ip + 1 raises(ValueError, lambda: ipr[-2]) assert ir.inf == i assert ir.sup == i + 18 raises(ValueError, lambda: Range(i).inf) # as_relational assert ir.as_relational(x) == ((x >= i) & (x <= i + 18) & Eq(Mod(-i + x, 2), 0)) assert ir2.as_relational(x) == Eq( Mod(-i + x, 3*i), 0) & (((x >= i) & (x <= 7*i) & (3*i >= 1)) | ((x <= i) & (x >= 7*i) & (3*i <= -1))) assert Range(i, i + 1).as_relational(x) == Eq(x, i) assert sr.as_relational(z) == Eq( Mod(t, 1), 0) & Eq(Mod(x, 1), 0) & Eq(Mod(-x + z, t), 0 ) & (((z >= x) & (z <= -t + y) & (t >= 1)) | ((z <= x) & (z >= -t + y) & (t <= -1))) assert xr.as_relational(z) == Eq(z, x) & Eq(Mod(x, 1), 0) # symbols can clash if user wants (but it must be integer) assert xr.as_relational(x) == Eq(Mod(x, 1), 0) # contains() for symbolic values (issue #18146) e = Symbol('e', integer=True, even=True) o = Symbol('o', integer=True, odd=True) assert Range(5).contains(i) == And(i >= 0, i <= 4) assert Range(1).contains(i) == Eq(i, 0) assert Range(-oo, 5, 1).contains(i) == (i <= 4) assert Range(-oo, oo).contains(i) == True assert Range(0, 8, 2).contains(i) == Contains(i, Range(0, 8, 2)) assert Range(0, 8, 2).contains(e) == And(e >= 0, e <= 6) assert Range(0, 8, 2).contains(2*i) == And(2*i >= 0, 2*i <= 6) assert Range(0, 8, 2).contains(o) == False assert Range(1, 9, 2).contains(e) == False assert Range(1, 9, 2).contains(o) == And(o >= 1, o <= 7) assert Range(8, 0, -2).contains(o) == False assert Range(9, 1, -2).contains(o) == And(o >= 3, o <= 9) assert Range(-oo, 8, 2).contains(i) == Contains(i, Range(-oo, 8, 2)) def test_range_range_intersection(): for a, b, r in [ (Range(0), Range(1), S.EmptySet), (Range(3), Range(4, oo), S.EmptySet), (Range(3), Range(-3, -1), S.EmptySet), (Range(1, 3), Range(0, 3), Range(1, 3)), (Range(1, 3), Range(1, 4), Range(1, 3)), (Range(1, oo, 2), Range(2, oo, 2), S.EmptySet), (Range(0, oo, 2), Range(oo), Range(0, oo, 2)), (Range(0, oo, 2), Range(100), Range(0, 100, 2)), (Range(2, oo, 2), Range(oo), Range(2, oo, 2)), (Range(0, oo, 2), Range(5, 6), S.EmptySet), (Range(2, 80, 1), Range(55, 71, 4), Range(55, 71, 4)), (Range(0, 6, 3), Range(-oo, 5, 3), S.EmptySet), (Range(0, oo, 2), Range(5, oo, 3), Range(8, oo, 6)), (Range(4, 6, 2), Range(2, 16, 7), S.EmptySet),]: assert a.intersect(b) == r assert a.intersect(b.reversed) == r assert a.reversed.intersect(b) == r assert a.reversed.intersect(b.reversed) == r a, b = b, a assert a.intersect(b) == r assert a.intersect(b.reversed) == r assert a.reversed.intersect(b) == r assert a.reversed.intersect(b.reversed) == r def test_range_interval_intersection(): p = symbols('p', positive=True) assert isinstance(Range(3).intersect(Interval(p, p + 2)), Intersection) assert Range(4).intersect(Interval(0, 3)) == Range(4) assert Range(4).intersect(Interval(-oo, oo)) == Range(4) assert Range(4).intersect(Interval(1, oo)) == Range(1, 4) assert Range(4).intersect(Interval(1.1, oo)) == Range(2, 4) assert Range(4).intersect(Interval(0.1, 3)) == Range(1, 4) assert Range(4).intersect(Interval(0.1, 3.1)) == Range(1, 4) assert Range(4).intersect(Interval.open(0, 3)) == Range(1, 3) assert Range(4).intersect(Interval.open(0.1, 0.5)) is S.EmptySet # Null Range intersections assert Range(0).intersect(Interval(0.2, 0.8)) is S.EmptySet assert Range(0).intersect(Interval(-oo, oo)) is S.EmptySet def test_range_is_finite_set(): assert Range(-100, 100).is_finite_set is True assert Range(2, oo).is_finite_set is False assert Range(-oo, 50).is_finite_set is False assert Range(-oo, oo).is_finite_set is False assert Range(oo, -oo).is_finite_set is True assert Range(0, 0).is_finite_set is True assert Range(oo, oo).is_finite_set is True assert Range(-oo, -oo).is_finite_set is True n = Symbol('n', integer=True) m = Symbol('m', integer=True) assert Range(n, n + 49).is_finite_set is True assert Range(n, 0).is_finite_set is True assert Range(-3, n + 7).is_finite_set is True assert Range(n, m).is_finite_set is True assert Range(n + m, m - n).is_finite_set is True assert Range(n, n + m + n).is_finite_set is True assert Range(n, oo).is_finite_set is False assert Range(-oo, n).is_finite_set is False # assert Range(n, -oo).is_finite_set is True # assert Range(oo, n).is_finite_set is True # Above tests fail due to a (potential) bug in sympy.sets.fancysets.Range.size (See issue #18999) def test_Integers_eval_imageset(): ans = ImageSet(Lambda(x, 2*x + Rational(3, 7)), S.Integers) im = imageset(Lambda(x, -2*x + Rational(3, 7)), S.Integers) assert im == ans im = imageset(Lambda(x, -2*x - Rational(11, 7)), S.Integers) assert im == ans y = Symbol('y') L = imageset(x, 2*x + y, S.Integers) assert y + 4 in L a, b, c = 0.092, 0.433, 0.341 assert a in imageset(x, a + c*x, S.Integers) assert b in imageset(x, b + c*x, S.Integers) _x = symbols('x', negative=True) eq = _x**2 - _x + 1 assert imageset(_x, eq, S.Integers).lamda.expr == _x**2 + _x + 1 eq = 3*_x - 1 assert imageset(_x, eq, S.Integers).lamda.expr == 3*_x + 2 assert imageset(x, (x, 1/x), S.Integers) == \ ImageSet(Lambda(x, (x, 1/x)), S.Integers) def test_Range_eval_imageset(): a, b, c = symbols('a b c') assert imageset(x, a*(x + b) + c, Range(3)) == \ imageset(x, a*x + a*b + c, Range(3)) eq = (x + 1)**2 assert imageset(x, eq, Range(3)).lamda.expr == eq eq = a*(x + b) + c r = Range(3, -3, -2) imset = imageset(x, eq, r) assert imset.lamda.expr != eq assert list(imset) == [eq.subs(x, i).expand() for i in list(r)] def test_fun(): assert (FiniteSet(*ImageSet(Lambda(x, sin(pi*x/4)), Range(-10, 11))) == FiniteSet(-1, -sqrt(2)/2, 0, sqrt(2)/2, 1)) def test_Reals(): assert 5 in S.Reals assert S.Pi in S.Reals assert -sqrt(2) in S.Reals assert (2, 5) not in S.Reals assert sqrt(-1) not in S.Reals assert S.Reals == Interval(-oo, oo) assert S.Reals != Interval(0, oo) assert S.Reals.is_subset(Interval(-oo, oo)) assert S.Reals.intersect(Range(-oo, oo)) == Range(-oo, oo) def test_Complex(): assert 5 in S.Complexes assert 5 + 4*I in S.Complexes assert S.Pi in S.Complexes assert -sqrt(2) in S.Complexes assert -I in S.Complexes assert sqrt(-1) in S.Complexes assert S.Complexes.intersect(S.Reals) == S.Reals assert S.Complexes.union(S.Reals) == S.Complexes assert S.Complexes == ComplexRegion(S.Reals*S.Reals) assert (S.Complexes == ComplexRegion(Interval(1, 2)*Interval(3, 4))) == False assert str(S.Complexes) == "S.Complexes" assert repr(S.Complexes) == "S.Complexes" def take(n, iterable): "Return first n items of the iterable as a list" return list(itertools.islice(iterable, n)) def test_intersections(): assert S.Integers.intersect(S.Reals) == S.Integers assert 5 in S.Integers.intersect(S.Reals) assert 5 in S.Integers.intersect(S.Reals) assert -5 not in S.Naturals.intersect(S.Reals) assert 5.5 not in S.Integers.intersect(S.Reals) assert 5 in S.Integers.intersect(Interval(3, oo)) assert -5 in S.Integers.intersect(Interval(-oo, 3)) assert all(x.is_Integer for x in take(10, S.Integers.intersect(Interval(3, oo)) )) def test_infinitely_indexed_set_1(): from sympy.abc import n, m, t assert imageset(Lambda(n, n), S.Integers) == imageset(Lambda(m, m), S.Integers) assert imageset(Lambda(n, 2*n), S.Integers).intersect( imageset(Lambda(m, 2*m + 1), S.Integers)) is S.EmptySet assert imageset(Lambda(n, 2*n), S.Integers).intersect( imageset(Lambda(n, 2*n + 1), S.Integers)) is S.EmptySet assert imageset(Lambda(m, 2*m), S.Integers).intersect( imageset(Lambda(n, 3*n), S.Integers)).dummy_eq( ImageSet(Lambda(t, 6*t), S.Integers)) assert imageset(x, x/2 + Rational(1, 3), S.Integers).intersect(S.Integers) is S.EmptySet assert imageset(x, x/2 + S.Half, S.Integers).intersect(S.Integers) is S.Integers # https://github.com/sympy/sympy/issues/17355 S53 = ImageSet(Lambda(n, 5*n + 3), S.Integers) assert S53.intersect(S.Integers) == S53 def test_infinitely_indexed_set_2(): from sympy.abc import n a = Symbol('a', integer=True) assert imageset(Lambda(n, n), S.Integers) == \ imageset(Lambda(n, n + a), S.Integers) assert imageset(Lambda(n, n + pi), S.Integers) == \ imageset(Lambda(n, n + a + pi), S.Integers) assert imageset(Lambda(n, n), S.Integers) == \ imageset(Lambda(n, -n + a), S.Integers) assert imageset(Lambda(n, -6*n), S.Integers) == \ ImageSet(Lambda(n, 6*n), S.Integers) assert imageset(Lambda(n, 2*n + pi), S.Integers) == \ ImageSet(Lambda(n, 2*n + pi - 2), S.Integers) def test_imageset_intersect_real(): from sympy import I from sympy.abc import n assert imageset(Lambda(n, n + (n - 1)*(n + 1)*I), S.Integers).intersect(S.Reals) == Complement(S.Integers, FiniteSet((-1, 1))) s = ImageSet( Lambda(n, -I*(I*(2*pi*n - pi/4) + log(Abs(sqrt(-I))))), S.Integers) # s is unevaluated, but after intersection the result # should be canonical assert s.intersect(S.Reals) == imageset( Lambda(n, 2*n*pi - pi/4), S.Integers) == ImageSet( Lambda(n, 2*pi*n + pi*Rational(7, 4)), S.Integers) def test_imageset_intersect_interval(): from sympy.abc import n f1 = ImageSet(Lambda(n, n*pi), S.Integers) f2 = ImageSet(Lambda(n, 2*n), Interval(0, pi)) f3 = ImageSet(Lambda(n, 2*n*pi + pi/2), S.Integers) # complex expressions f4 = ImageSet(Lambda(n, n*I*pi), S.Integers) f5 = ImageSet(Lambda(n, 2*I*n*pi + pi/2), S.Integers) # non-linear expressions f6 = ImageSet(Lambda(n, log(n)), S.Integers) f7 = ImageSet(Lambda(n, n**2), S.Integers) f8 = ImageSet(Lambda(n, Abs(n)), S.Integers) f9 = ImageSet(Lambda(n, exp(n)), S.Naturals0) assert f1.intersect(Interval(-1, 1)) == FiniteSet(0) assert f1.intersect(Interval(0, 2*pi, False, True)) == FiniteSet(0, pi) assert f2.intersect(Interval(1, 2)) == Interval(1, 2) assert f3.intersect(Interval(-1, 1)) == S.EmptySet assert f3.intersect(Interval(-5, 5)) == FiniteSet(pi*Rational(-3, 2), pi/2) assert f4.intersect(Interval(-1, 1)) == FiniteSet(0) assert f4.intersect(Interval(1, 2)) == S.EmptySet assert f5.intersect(Interval(0, 1)) == S.EmptySet assert f6.intersect(Interval(0, 1)) == FiniteSet(S.Zero, log(2)) assert f7.intersect(Interval(0, 10)) == Intersection(f7, Interval(0, 10)) assert f8.intersect(Interval(0, 2)) == Intersection(f8, Interval(0, 2)) assert f9.intersect(Interval(1, 2)) == Intersection(f9, Interval(1, 2)) def test_imageset_intersect_diophantine(): from sympy.abc import m, n # Check that same lambda variable for both ImageSets is handled correctly img1 = ImageSet(Lambda(n, 2*n + 1), S.Integers) img2 = ImageSet(Lambda(n, 4*n + 1), S.Integers) assert img1.intersect(img2) == img2 # Empty solution set returned by diophantine: assert ImageSet(Lambda(n, 2*n), S.Integers).intersect( ImageSet(Lambda(n, 2*n + 1), S.Integers)) == S.EmptySet # Check intersection with S.Integers: assert ImageSet(Lambda(n, 9/n + 20*n/3), S.Integers).intersect( S.Integers) == FiniteSet(-61, -23, 23, 61) # Single solution (2, 3) for diophantine solution: assert ImageSet(Lambda(n, (n - 2)**2), S.Integers).intersect( ImageSet(Lambda(n, -(n - 3)**2), S.Integers)) == FiniteSet(0) # Single parametric solution for diophantine solution: assert ImageSet(Lambda(n, n**2 + 5), S.Integers).intersect( ImageSet(Lambda(m, 2*m), S.Integers)).dummy_eq(ImageSet( Lambda(n, 4*n**2 + 4*n + 6), S.Integers)) # 4 non-parametric solution couples for dioph. equation: assert ImageSet(Lambda(n, n**2 - 9), S.Integers).intersect( ImageSet(Lambda(m, -m**2), S.Integers)) == FiniteSet(-9, 0) # Double parametric solution for diophantine solution: assert ImageSet(Lambda(m, m**2 + 40), S.Integers).intersect( ImageSet(Lambda(n, 41*n), S.Integers)).dummy_eq(Intersection( ImageSet(Lambda(m, m**2 + 40), S.Integers), ImageSet(Lambda(n, 41*n), S.Integers))) # Check that diophantine returns *all* (8) solutions (permute=True) assert ImageSet(Lambda(n, n**4 - 2**4), S.Integers).intersect( ImageSet(Lambda(m, -m**4 + 3**4), S.Integers)) == FiniteSet(0, 65) assert ImageSet(Lambda(n, pi/12 + n*5*pi/12), S.Integers).intersect( ImageSet(Lambda(n, 7*pi/12 + n*11*pi/12), S.Integers)).dummy_eq(ImageSet( Lambda(n, 55*pi*n/12 + 17*pi/4), S.Integers)) # TypeError raised by diophantine (#18081) assert ImageSet(Lambda(n, n*log(2)), S.Integers).intersection( S.Integers).dummy_eq(Intersection(ImageSet( Lambda(n, n*log(2)), S.Integers), S.Integers)) # NotImplementedError raised by diophantine (no solver for cubic_thue) assert ImageSet(Lambda(n, n**3 + 1), S.Integers).intersect( ImageSet(Lambda(n, n**3), S.Integers)).dummy_eq(Intersection( ImageSet(Lambda(n, n**3 + 1), S.Integers), ImageSet(Lambda(n, n**3), S.Integers))) def test_infinitely_indexed_set_3(): from sympy.abc import n, m, t assert imageset(Lambda(m, 2*pi*m), S.Integers).intersect( imageset(Lambda(n, 3*pi*n), S.Integers)).dummy_eq( ImageSet(Lambda(t, 6*pi*t), S.Integers)) assert imageset(Lambda(n, 2*n + 1), S.Integers) == \ imageset(Lambda(n, 2*n - 1), S.Integers) assert imageset(Lambda(n, 3*n + 2), S.Integers) == \ imageset(Lambda(n, 3*n - 1), S.Integers) def test_ImageSet_simplification(): from sympy.abc import n, m assert imageset(Lambda(n, n), S.Integers) == S.Integers assert imageset(Lambda(n, sin(n)), imageset(Lambda(m, tan(m)), S.Integers)) == \ imageset(Lambda(m, sin(tan(m))), S.Integers) assert imageset(n, 1 + 2*n, S.Naturals) == Range(3, oo, 2) assert imageset(n, 1 + 2*n, S.Naturals0) == Range(1, oo, 2) assert imageset(n, 1 - 2*n, S.Naturals) == Range(-1, -oo, -2) def test_ImageSet_contains(): from sympy.abc import x assert (2, S.Half) in imageset(x, (x, 1/x), S.Integers) assert imageset(x, x + I*3, S.Integers).intersection(S.Reals) is S.EmptySet i = Dummy(integer=True) q = imageset(x, x + I*y, S.Integers).intersection(S.Reals) assert q.subs(y, I*i).intersection(S.Integers) is S.Integers q = imageset(x, x + I*y/x, S.Integers).intersection(S.Reals) assert q.subs(y, 0) is S.Integers assert q.subs(y, I*i*x).intersection(S.Integers) is S.Integers z = cos(1)**2 + sin(1)**2 - 1 q = imageset(x, x + I*z, S.Integers).intersection(S.Reals) assert q is not S.EmptySet def test_ComplexRegion_contains(): r = Symbol('r', real=True) # contains in ComplexRegion a = Interval(2, 3) b = Interval(4, 6) c = Interval(7, 9) c1 = ComplexRegion(a*b) c2 = ComplexRegion(Union(a*b, c*a)) assert 2.5 + 4.5*I in c1 assert 2 + 4*I in c1 assert 3 + 4*I in c1 assert 8 + 2.5*I in c2 assert 2.5 + 6.1*I not in c1 assert 4.5 + 3.2*I not in c1 assert c1.contains(x) == Contains(x, c1, evaluate=False) assert c1.contains(r) == False assert c2.contains(x) == Contains(x, c2, evaluate=False) assert c2.contains(r) == False r1 = Interval(0, 1) theta1 = Interval(0, 2*S.Pi) c3 = ComplexRegion(r1*theta1, polar=True) assert (0.5 + I*Rational(6, 10)) in c3 assert (S.Half + I*Rational(6, 10)) in c3 assert (S.Half + .6*I) in c3 assert (0.5 + .6*I) in c3 assert I in c3 assert 1 in c3 assert 0 in c3 assert 1 + I not in c3 assert 1 - I not in c3 assert c3.contains(x) == Contains(x, c3, evaluate=False) assert c3.contains(r + 2*I) == Contains( r + 2*I, c3, evaluate=False) # is in fact False assert c3.contains(1/(1 + r**2)) == Contains( 1/(1 + r**2), c3, evaluate=False) # is in fact True r2 = Interval(0, 3) theta2 = Interval(pi, 2*pi, left_open=True) c4 = ComplexRegion(r2*theta2, polar=True) assert c4.contains(0) == True assert c4.contains(2 + I) == False assert c4.contains(-2 + I) == False assert c4.contains(-2 - I) == True assert c4.contains(2 - I) == True assert c4.contains(-2) == False assert c4.contains(2) == True assert c4.contains(x) == Contains(x, c4, evaluate=False) assert c4.contains(3/(1 + r**2)) == Contains( 3/(1 + r**2), c4, evaluate=False) # is in fact True raises(ValueError, lambda: ComplexRegion(r1*theta1, polar=2)) def test_ComplexRegion_intersect(): # Polar form X_axis = ComplexRegion(Interval(0, oo)*FiniteSet(0, S.Pi), polar=True) unit_disk = ComplexRegion(Interval(0, 1)*Interval(0, 2*S.Pi), polar=True) upper_half_unit_disk = ComplexRegion(Interval(0, 1)*Interval(0, S.Pi), polar=True) upper_half_disk = ComplexRegion(Interval(0, oo)*Interval(0, S.Pi), polar=True) lower_half_disk = ComplexRegion(Interval(0, oo)*Interval(S.Pi, 2*S.Pi), polar=True) right_half_disk = ComplexRegion(Interval(0, oo)*Interval(-S.Pi/2, S.Pi/2), polar=True) first_quad_disk = ComplexRegion(Interval(0, oo)*Interval(0, S.Pi/2), polar=True) assert upper_half_disk.intersect(unit_disk) == upper_half_unit_disk assert right_half_disk.intersect(first_quad_disk) == first_quad_disk assert upper_half_disk.intersect(right_half_disk) == first_quad_disk assert upper_half_disk.intersect(lower_half_disk) == X_axis c1 = ComplexRegion(Interval(0, 4)*Interval(0, 2*S.Pi), polar=True) assert c1.intersect(Interval(1, 5)) == Interval(1, 4) assert c1.intersect(Interval(4, 9)) == FiniteSet(4) assert c1.intersect(Interval(5, 12)) is S.EmptySet # Rectangular form X_axis = ComplexRegion(Interval(-oo, oo)*FiniteSet(0)) unit_square = ComplexRegion(Interval(-1, 1)*Interval(-1, 1)) upper_half_unit_square = ComplexRegion(Interval(-1, 1)*Interval(0, 1)) upper_half_plane = ComplexRegion(Interval(-oo, oo)*Interval(0, oo)) lower_half_plane = ComplexRegion(Interval(-oo, oo)*Interval(-oo, 0)) right_half_plane = ComplexRegion(Interval(0, oo)*Interval(-oo, oo)) first_quad_plane = ComplexRegion(Interval(0, oo)*Interval(0, oo)) assert upper_half_plane.intersect(unit_square) == upper_half_unit_square assert right_half_plane.intersect(first_quad_plane) == first_quad_plane assert upper_half_plane.intersect(right_half_plane) == first_quad_plane assert upper_half_plane.intersect(lower_half_plane) == X_axis c1 = ComplexRegion(Interval(-5, 5)*Interval(-10, 10)) assert c1.intersect(Interval(2, 7)) == Interval(2, 5) assert c1.intersect(Interval(5, 7)) == FiniteSet(5) assert c1.intersect(Interval(6, 9)) is S.EmptySet # unevaluated object C1 = ComplexRegion(Interval(0, 1)*Interval(0, 2*S.Pi), polar=True) C2 = ComplexRegion(Interval(-1, 1)*Interval(-1, 1)) assert C1.intersect(C2) == Intersection(C1, C2, evaluate=False) def test_ComplexRegion_union(): # Polar form c1 = ComplexRegion(Interval(0, 1)*Interval(0, 2*S.Pi), polar=True) c2 = ComplexRegion(Interval(0, 1)*Interval(0, S.Pi), polar=True) c3 = ComplexRegion(Interval(0, oo)*Interval(0, S.Pi), polar=True) c4 = ComplexRegion(Interval(0, oo)*Interval(S.Pi, 2*S.Pi), polar=True) p1 = Union(Interval(0, 1)*Interval(0, 2*S.Pi), Interval(0, 1)*Interval(0, S.Pi)) p2 = Union(Interval(0, oo)*Interval(0, S.Pi), Interval(0, oo)*Interval(S.Pi, 2*S.Pi)) assert c1.union(c2) == ComplexRegion(p1, polar=True) assert c3.union(c4) == ComplexRegion(p2, polar=True) # Rectangular form c5 = ComplexRegion(Interval(2, 5)*Interval(6, 9)) c6 = ComplexRegion(Interval(4, 6)*Interval(10, 12)) c7 = ComplexRegion(Interval(0, 10)*Interval(-10, 0)) c8 = ComplexRegion(Interval(12, 16)*Interval(14, 20)) p3 = Union(Interval(2, 5)*Interval(6, 9), Interval(4, 6)*Interval(10, 12)) p4 = Union(Interval(0, 10)*Interval(-10, 0), Interval(12, 16)*Interval(14, 20)) assert c5.union(c6) == ComplexRegion(p3) assert c7.union(c8) == ComplexRegion(p4) assert c1.union(Interval(2, 4)) == Union(c1, Interval(2, 4), evaluate=False) assert c5.union(Interval(2, 4)) == Union(c5, ComplexRegion.from_real(Interval(2, 4))) def test_ComplexRegion_from_real(): c1 = ComplexRegion(Interval(0, 1) * Interval(0, 2 * S.Pi), polar=True) raises(ValueError, lambda: c1.from_real(c1)) assert c1.from_real(Interval(-1, 1)) == ComplexRegion(Interval(-1, 1) * FiniteSet(0), False) def test_ComplexRegion_measure(): a, b = Interval(2, 5), Interval(4, 8) theta1, theta2 = Interval(0, 2*S.Pi), Interval(0, S.Pi) c1 = ComplexRegion(a*b) c2 = ComplexRegion(Union(a*theta1, b*theta2), polar=True) assert c1.measure == 12 assert c2.measure == 9*pi def test_normalize_theta_set(): # Interval assert normalize_theta_set(Interval(pi, 2*pi)) == \ Union(FiniteSet(0), Interval.Ropen(pi, 2*pi)) assert normalize_theta_set(Interval(pi*Rational(9, 2), 5*pi)) == Interval(pi/2, pi) assert normalize_theta_set(Interval(pi*Rational(-3, 2), pi/2)) == Interval.Ropen(0, 2*pi) assert normalize_theta_set(Interval.open(pi*Rational(-3, 2), pi/2)) == \ Union(Interval.Ropen(0, pi/2), Interval.open(pi/2, 2*pi)) assert normalize_theta_set(Interval.open(pi*Rational(-7, 2), pi*Rational(-3, 2))) == \ Union(Interval.Ropen(0, pi/2), Interval.open(pi/2, 2*pi)) assert normalize_theta_set(Interval(-pi/2, pi/2)) == \ Union(Interval(0, pi/2), Interval.Ropen(pi*Rational(3, 2), 2*pi)) assert normalize_theta_set(Interval.open(-pi/2, pi/2)) == \ Union(Interval.Ropen(0, pi/2), Interval.open(pi*Rational(3, 2), 2*pi)) assert normalize_theta_set(Interval(-4*pi, 3*pi)) == Interval.Ropen(0, 2*pi) assert normalize_theta_set(Interval(pi*Rational(-3, 2), -pi/2)) == Interval(pi/2, pi*Rational(3, 2)) assert normalize_theta_set(Interval.open(0, 2*pi)) == Interval.open(0, 2*pi) assert normalize_theta_set(Interval.Ropen(-pi/2, pi/2)) == \ Union(Interval.Ropen(0, pi/2), Interval.Ropen(pi*Rational(3, 2), 2*pi)) assert normalize_theta_set(Interval.Lopen(-pi/2, pi/2)) == \ Union(Interval(0, pi/2), Interval.open(pi*Rational(3, 2), 2*pi)) assert normalize_theta_set(Interval(-pi/2, pi/2)) == \ Union(Interval(0, pi/2), Interval.Ropen(pi*Rational(3, 2), 2*pi)) assert normalize_theta_set(Interval.open(4*pi, pi*Rational(9, 2))) == Interval.open(0, pi/2) assert normalize_theta_set(Interval.Lopen(4*pi, pi*Rational(9, 2))) == Interval.Lopen(0, pi/2) assert normalize_theta_set(Interval.Ropen(4*pi, pi*Rational(9, 2))) == Interval.Ropen(0, pi/2) assert normalize_theta_set(Interval.open(3*pi, 5*pi)) == \ Union(Interval.Ropen(0, pi), Interval.open(pi, 2*pi)) # FiniteSet assert normalize_theta_set(FiniteSet(0, pi, 3*pi)) == FiniteSet(0, pi) assert normalize_theta_set(FiniteSet(0, pi/2, pi, 2*pi)) == FiniteSet(0, pi/2, pi) assert normalize_theta_set(FiniteSet(0, -pi/2, -pi, -2*pi)) == FiniteSet(0, pi, pi*Rational(3, 2)) assert normalize_theta_set(FiniteSet(pi*Rational(-3, 2), pi/2)) == \ FiniteSet(pi/2) assert normalize_theta_set(FiniteSet(2*pi)) == FiniteSet(0) # Unions assert normalize_theta_set(Union(Interval(0, pi/3), Interval(pi/2, pi))) == \ Union(Interval(0, pi/3), Interval(pi/2, pi)) assert normalize_theta_set(Union(Interval(0, pi), Interval(2*pi, pi*Rational(7, 3)))) == \ Interval(0, pi) # ValueError for non-real sets raises(ValueError, lambda: normalize_theta_set(S.Complexes)) # NotImplementedError for subset of reals raises(NotImplementedError, lambda: normalize_theta_set(Interval(0, 1))) # NotImplementedError without pi as coefficient raises(NotImplementedError, lambda: normalize_theta_set(Interval(1, 2*pi))) raises(NotImplementedError, lambda: normalize_theta_set(Interval(2*pi, 10))) raises(NotImplementedError, lambda: normalize_theta_set(FiniteSet(0, 3, 3*pi))) def test_ComplexRegion_FiniteSet(): x, y, z, a, b, c = symbols('x y z a b c') # Issue #9669 assert ComplexRegion(FiniteSet(a, b, c)*FiniteSet(x, y, z)) == \ FiniteSet(a + I*x, a + I*y, a + I*z, b + I*x, b + I*y, b + I*z, c + I*x, c + I*y, c + I*z) assert ComplexRegion(FiniteSet(2)*FiniteSet(3)) == FiniteSet(2 + 3*I) def test_union_RealSubSet(): assert (S.Complexes).union(Interval(1, 2)) == S.Complexes assert (S.Complexes).union(S.Integers) == S.Complexes def test_issue_9980(): c1 = ComplexRegion(Interval(1, 2)*Interval(2, 3)) c2 = ComplexRegion(Interval(1, 5)*Interval(1, 3)) R = Union(c1, c2) assert simplify(R) == ComplexRegion(Union(Interval(1, 2)*Interval(2, 3), \ Interval(1, 5)*Interval(1, 3)), False) assert c1.func(*c1.args) == c1 assert R.func(*R.args) == R def test_issue_11732(): interval12 = Interval(1, 2) finiteset1234 = FiniteSet(1, 2, 3, 4) pointComplex = Tuple(1, 5) assert (interval12 in S.Naturals) == False assert (interval12 in S.Naturals0) == False assert (interval12 in S.Integers) == False assert (interval12 in S.Complexes) == False assert (finiteset1234 in S.Naturals) == False assert (finiteset1234 in S.Naturals0) == False assert (finiteset1234 in S.Integers) == False assert (finiteset1234 in S.Complexes) == False assert (pointComplex in S.Naturals) == False assert (pointComplex in S.Naturals0) == False assert (pointComplex in S.Integers) == False assert (pointComplex in S.Complexes) == True def test_issue_11730(): unit = Interval(0, 1) square = ComplexRegion(unit ** 2) assert Union(S.Complexes, FiniteSet(oo)) != S.Complexes assert Union(S.Complexes, FiniteSet(eye(4))) != S.Complexes assert Union(unit, square) == square assert Intersection(S.Reals, square) == unit def test_issue_11938(): unit = Interval(0, 1) ival = Interval(1, 2) cr1 = ComplexRegion(ival * unit) assert Intersection(cr1, S.Reals) == ival assert Intersection(cr1, unit) == FiniteSet(1) arg1 = Interval(0, S.Pi) arg2 = FiniteSet(S.Pi) arg3 = Interval(S.Pi / 4, 3 * S.Pi / 4) cp1 = ComplexRegion(unit * arg1, polar=True) cp2 = ComplexRegion(unit * arg2, polar=True) cp3 = ComplexRegion(unit * arg3, polar=True) assert Intersection(cp1, S.Reals) == Interval(-1, 1) assert Intersection(cp2, S.Reals) == Interval(-1, 0) assert Intersection(cp3, S.Reals) == FiniteSet(0) def test_issue_11914(): a, b = Interval(0, 1), Interval(0, pi) c, d = Interval(2, 3), Interval(pi, 3 * pi / 2) cp1 = ComplexRegion(a * b, polar=True) cp2 = ComplexRegion(c * d, polar=True) assert -3 in cp1.union(cp2) assert -3 in cp2.union(cp1) assert -5 not in cp1.union(cp2) def test_issue_9543(): assert ImageSet(Lambda(x, x**2), S.Naturals).is_subset(S.Reals) def test_issue_16871(): assert ImageSet(Lambda(x, x), FiniteSet(1)) == {1} assert ImageSet(Lambda(x, x - 3), S.Integers ).intersection(S.Integers) is S.Integers @XFAIL def test_issue_16871b(): assert ImageSet(Lambda(x, x - 3), S.Integers).is_subset(S.Integers) def test_issue_18050(): assert imageset(Lambda(x, I*x + 1), S.Integers ) == ImageSet(Lambda(x, I*x + 1), S.Integers) assert imageset(Lambda(x, 3*I*x + 4 + 8*I), S.Integers ) == ImageSet(Lambda(x, 3*I*x + 4 + 2*I), S.Integers) # no 'Mod' for next 2 tests: assert imageset(Lambda(x, 2*x + 3*I), S.Integers ) == ImageSet(Lambda(x, 2*x + 3*I), S.Integers) r = Symbol('r', positive=True) assert imageset(Lambda(x, r*x + 10), S.Integers ) == ImageSet(Lambda(x, r*x + 10), S.Integers) # reduce real part: assert imageset(Lambda(x, 3*x + 8 + 5*I), S.Integers ) == ImageSet(Lambda(x, 3*x + 2 + 5*I), S.Integers) def test_Rationals(): assert S.Integers.is_subset(S.Rationals) assert S.Naturals.is_subset(S.Rationals) assert S.Naturals0.is_subset(S.Rationals) assert S.Rationals.is_subset(S.Reals) assert S.Rationals.inf is -oo assert S.Rationals.sup is oo it = iter(S.Rationals) assert [next(it) for i in range(12)] == [ 0, 1, -1, S.Half, 2, Rational(-1, 2), -2, Rational(1, 3), 3, Rational(-1, 3), -3, Rational(2, 3)] assert Basic() not in S.Rationals assert S.Half in S.Rationals assert S.Rationals.contains(0.5) == Contains(0.5, S.Rationals, evaluate=False) assert 2 in S.Rationals r = symbols('r', rational=True) assert r in S.Rationals raises(TypeError, lambda: x in S.Rationals) # issue #18134: assert S.Rationals.boundary == S.Reals assert S.Rationals.closure == S.Reals assert S.Rationals.is_open == False assert S.Rationals.is_closed == False def test_NZQRC_unions(): # check that all trivial number set unions are simplified: nbrsets = (S.Naturals, S.Naturals0, S.Integers, S.Rationals, S.Reals, S.Complexes) unions = (Union(a, b) for a in nbrsets for b in nbrsets) assert all(u.is_Union is False for u in unions) def test_imageset_intersection(): n = Dummy() s = ImageSet(Lambda(n, -I*(I*(2*pi*n - pi/4) + log(Abs(sqrt(-I))))), S.Integers) assert s.intersect(S.Reals) == ImageSet( Lambda(n, 2*pi*n + pi*Rational(7, 4)), S.Integers) def test_issue_17858(): assert 1 in Range(-oo, oo) assert 0 in Range(oo, -oo, -1) assert oo not in Range(-oo, oo) assert -oo not in Range(-oo, oo) def test_issue_17859(): r = Range(-oo,oo) raises(ValueError,lambda: r[::2]) raises(ValueError, lambda: r[::-2]) r = Range(oo,-oo,-1) raises(ValueError,lambda: r[::2]) raises(ValueError, lambda: r[::-2])
6a2611c341bf5b6110729ba491cac05ca23859b6be2e40b02e89c337b15f972e
from sympy import (Symbol, Set, Union, Interval, oo, S, sympify, nan, Max, Min, Float, DisjointUnion, FiniteSet, Intersection, imageset, I, true, false, ProductSet, sqrt, Complement, EmptySet, sin, cos, Lambda, ImageSet, pi, Pow, Contains, Sum, rootof, SymmetricDifference, Piecewise, Matrix, Range, Add, symbols, zoo, Rational) from mpmath import mpi from sympy.core.expr import unchanged from sympy.core.relational import Eq, Ne, Le, Lt, LessThan from sympy.logic import And, Or, Xor from sympy.testing.pytest import raises, XFAIL, warns_deprecated_sympy from sympy.abc import x, y, z, m, n def test_imageset(): ints = S.Integers assert imageset(x, x - 1, S.Naturals) is S.Naturals0 assert imageset(x, x + 1, S.Naturals0) is S.Naturals assert imageset(x, abs(x), S.Naturals0) is S.Naturals0 assert imageset(x, abs(x), S.Naturals) is S.Naturals assert imageset(x, abs(x), S.Integers) is S.Naturals0 # issue 16878a r = symbols('r', real=True) assert imageset(x, (x, x), S.Reals)._contains((1, r)) == None assert imageset(x, (x, x), S.Reals)._contains((1, 2)) == False assert (r, r) in imageset(x, (x, x), S.Reals) assert 1 + I in imageset(x, x + I, S.Reals) assert {1} not in imageset(x, (x,), S.Reals) assert (1, 1) not in imageset(x, (x,) , S.Reals) raises(TypeError, lambda: imageset(x, ints)) raises(ValueError, lambda: imageset(x, y, z, ints)) raises(ValueError, lambda: imageset(Lambda(x, cos(x)), y)) assert (1, 2) in imageset(Lambda((x, y), (x, y)), ints, ints) raises(ValueError, lambda: imageset(Lambda(x, x), ints, ints)) assert imageset(cos, ints) == ImageSet(Lambda(x, cos(x)), ints) def f(x): return cos(x) assert imageset(f, ints) == imageset(x, cos(x), ints) f = lambda x: cos(x) assert imageset(f, ints) == ImageSet(Lambda(x, cos(x)), ints) assert imageset(x, 1, ints) == FiniteSet(1) assert imageset(x, y, ints) == {y} assert imageset((x, y), (1, z), ints, S.Reals) == {(1, z)} clash = Symbol('x', integer=true) assert (str(imageset(lambda x: x + clash, Interval(-2, 1)).lamda.expr) in ('x0 + x', 'x + x0')) x1, x2 = symbols("x1, x2") assert imageset(lambda x, y: Add(x, y), Interval(1, 2), Interval(2, 3)).dummy_eq( ImageSet(Lambda((x1, x2), x1 + x2), Interval(1, 2), Interval(2, 3))) def test_is_empty(): for s in [S.Naturals, S.Naturals0, S.Integers, S.Rationals, S.Reals, S.UniversalSet]: assert s.is_empty is False assert S.EmptySet.is_empty is True def test_is_finiteset(): for s in [S.Naturals, S.Naturals0, S.Integers, S.Rationals, S.Reals, S.UniversalSet]: assert s.is_finite_set is False assert S.EmptySet.is_finite_set is True assert FiniteSet(1, 2).is_finite_set is True assert Interval(1, 2).is_finite_set is False assert Interval(x, y).is_finite_set is None assert ProductSet(FiniteSet(1), FiniteSet(2)).is_finite_set is True assert ProductSet(FiniteSet(1), Interval(1, 2)).is_finite_set is False assert ProductSet(FiniteSet(1), Interval(x, y)).is_finite_set is None assert Union(Interval(0, 1), Interval(2, 3)).is_finite_set is False assert Union(FiniteSet(1), Interval(2, 3)).is_finite_set is False assert Union(FiniteSet(1), FiniteSet(2)).is_finite_set is True assert Union(FiniteSet(1), Interval(x, y)).is_finite_set is None assert Intersection(Interval(x, y), FiniteSet(1)).is_finite_set is True assert Intersection(Interval(x, y), Interval(1, 2)).is_finite_set is None assert Intersection(FiniteSet(x), FiniteSet(y)).is_finite_set is True assert Complement(FiniteSet(1), Interval(x, y)).is_finite_set is True assert Complement(Interval(x, y), FiniteSet(1)).is_finite_set is None assert Complement(Interval(1, 2), FiniteSet(x)).is_finite_set is False assert DisjointUnion(Interval(-5, 3), FiniteSet(x, y)).is_finite_set is False assert DisjointUnion(S.EmptySet, FiniteSet(x, y), S.EmptySet).is_finite_set is True def test_deprecated_is_EmptySet(): with warns_deprecated_sympy(): S.EmptySet.is_EmptySet def test_interval_arguments(): assert Interval(0, oo) == Interval(0, oo, False, True) assert Interval(0, oo).right_open is true assert Interval(-oo, 0) == Interval(-oo, 0, True, False) assert Interval(-oo, 0).left_open is true assert Interval(oo, -oo) == S.EmptySet assert Interval(oo, oo) == S.EmptySet assert Interval(-oo, -oo) == S.EmptySet assert Interval(oo, x) == S.EmptySet assert Interval(oo, oo) == S.EmptySet assert Interval(x, -oo) == S.EmptySet assert Interval(x, x) == {x} assert isinstance(Interval(1, 1), FiniteSet) e = Sum(x, (x, 1, 3)) assert isinstance(Interval(e, e), FiniteSet) assert Interval(1, 0) == S.EmptySet assert Interval(1, 1).measure == 0 assert Interval(1, 1, False, True) == S.EmptySet assert Interval(1, 1, True, False) == S.EmptySet assert Interval(1, 1, True, True) == S.EmptySet assert isinstance(Interval(0, Symbol('a')), Interval) assert Interval(Symbol('a', real=True, positive=True), 0) == S.EmptySet raises(ValueError, lambda: Interval(0, S.ImaginaryUnit)) raises(ValueError, lambda: Interval(0, Symbol('z', extended_real=False))) raises(ValueError, lambda: Interval(x, x + S.ImaginaryUnit)) raises(NotImplementedError, lambda: Interval(0, 1, And(x, y))) raises(NotImplementedError, lambda: Interval(0, 1, False, And(x, y))) raises(NotImplementedError, lambda: Interval(0, 1, z, And(x, y))) def test_interval_symbolic_end_points(): a = Symbol('a', real=True) assert Union(Interval(0, a), Interval(0, 3)).sup == Max(a, 3) assert Union(Interval(a, 0), Interval(-3, 0)).inf == Min(-3, a) assert Interval(0, a).contains(1) == LessThan(1, a) def test_interval_is_empty(): x, y = symbols('x, y') r = Symbol('r', real=True) p = Symbol('p', positive=True) n = Symbol('n', negative=True) nn = Symbol('nn', nonnegative=True) assert Interval(1, 2).is_empty == False assert Interval(3, 3).is_empty == False # FiniteSet assert Interval(r, r).is_empty == False # FiniteSet assert Interval(r, r + nn).is_empty == False assert Interval(x, x).is_empty == False assert Interval(1, oo).is_empty == False assert Interval(-oo, oo).is_empty == False assert Interval(-oo, 1).is_empty == False assert Interval(x, y).is_empty == None assert Interval(r, oo).is_empty == False # real implies finite assert Interval(n, 0).is_empty == False assert Interval(n, 0, left_open=True).is_empty == False assert Interval(p, 0).is_empty == True # EmptySet assert Interval(nn, 0).is_empty == None assert Interval(n, p).is_empty == False assert Interval(0, p, left_open=True).is_empty == False assert Interval(0, p, right_open=True).is_empty == False assert Interval(0, nn, left_open=True).is_empty == None assert Interval(0, nn, right_open=True).is_empty == None def test_union(): assert Union(Interval(1, 2), Interval(2, 3)) == Interval(1, 3) assert Union(Interval(1, 2), Interval(2, 3, True)) == Interval(1, 3) assert Union(Interval(1, 3), Interval(2, 4)) == Interval(1, 4) assert Union(Interval(1, 2), Interval(1, 3)) == Interval(1, 3) assert Union(Interval(1, 3), Interval(1, 2)) == Interval(1, 3) assert Union(Interval(1, 3, False, True), Interval(1, 2)) == \ Interval(1, 3, False, True) assert Union(Interval(1, 3), Interval(1, 2, False, True)) == Interval(1, 3) assert Union(Interval(1, 2, True), Interval(1, 3)) == Interval(1, 3) assert Union(Interval(1, 2, True), Interval(1, 3, True)) == \ Interval(1, 3, True) assert Union(Interval(1, 2, True), Interval(1, 3, True, True)) == \ Interval(1, 3, True, True) assert Union(Interval(1, 2, True, True), Interval(1, 3, True)) == \ Interval(1, 3, True) assert Union(Interval(1, 3), Interval(2, 3)) == Interval(1, 3) assert Union(Interval(1, 3, False, True), Interval(2, 3)) == \ Interval(1, 3) assert Union(Interval(1, 2, False, True), Interval(2, 3, True)) != \ Interval(1, 3) assert Union(Interval(1, 2), S.EmptySet) == Interval(1, 2) assert Union(S.EmptySet) == S.EmptySet assert Union(Interval(0, 1), *[FiniteSet(1.0/n) for n in range(1, 10)]) == \ Interval(0, 1) # issue #18241: x = Symbol('x') assert Union(Interval(0, 1), FiniteSet(1, x)) == Union( Interval(0, 1), FiniteSet(x)) assert unchanged(Union, Interval(0, 1), FiniteSet(2, x)) assert Interval(1, 2).union(Interval(2, 3)) == \ Interval(1, 2) + Interval(2, 3) assert Interval(1, 2).union(Interval(2, 3)) == Interval(1, 3) assert Union(Set()) == Set() assert FiniteSet(1) + FiniteSet(2) + FiniteSet(3) == FiniteSet(1, 2, 3) assert FiniteSet('ham') + FiniteSet('eggs') == FiniteSet('ham', 'eggs') assert FiniteSet(1, 2, 3) + S.EmptySet == FiniteSet(1, 2, 3) assert FiniteSet(1, 2, 3) & FiniteSet(2, 3, 4) == FiniteSet(2, 3) assert FiniteSet(1, 2, 3) | FiniteSet(2, 3, 4) == FiniteSet(1, 2, 3, 4) assert FiniteSet(1, 2, 3) & S.EmptySet == S.EmptySet assert FiniteSet(1, 2, 3) | S.EmptySet == FiniteSet(1, 2, 3) x = Symbol("x") y = Symbol("y") z = Symbol("z") assert S.EmptySet | FiniteSet(x, FiniteSet(y, z)) == \ FiniteSet(x, FiniteSet(y, z)) # Test that Intervals and FiniteSets play nicely assert Interval(1, 3) + FiniteSet(2) == Interval(1, 3) assert Interval(1, 3, True, True) + FiniteSet(3) == \ Interval(1, 3, True, False) X = Interval(1, 3) + FiniteSet(5) Y = Interval(1, 2) + FiniteSet(3) XandY = X.intersect(Y) assert 2 in X and 3 in X and 3 in XandY assert XandY.is_subset(X) and XandY.is_subset(Y) raises(TypeError, lambda: Union(1, 2, 3)) assert X.is_iterable is False # issue 7843 assert Union(S.EmptySet, FiniteSet(-sqrt(-I), sqrt(-I))) == \ FiniteSet(-sqrt(-I), sqrt(-I)) assert Union(S.Reals, S.Integers) == S.Reals def test_union_iter(): # Use Range because it is ordered u = Union(Range(3), Range(5), Range(4), evaluate=False) # Round robin assert list(u) == [0, 0, 0, 1, 1, 1, 2, 2, 2, 3, 3, 4] def test_union_is_empty(): assert (Interval(x, y) + FiniteSet(1)).is_empty == False assert (Interval(x, y) + Interval(-x, y)).is_empty == None def test_difference(): assert Interval(1, 3) - Interval(1, 2) == Interval(2, 3, True) assert Interval(1, 3) - Interval(2, 3) == Interval(1, 2, False, True) assert Interval(1, 3, True) - Interval(2, 3) == Interval(1, 2, True, True) assert Interval(1, 3, True) - Interval(2, 3, True) == \ Interval(1, 2, True, False) assert Interval(0, 2) - FiniteSet(1) == \ Union(Interval(0, 1, False, True), Interval(1, 2, True, False)) # issue #18119 assert S.Reals - FiniteSet(I) == S.Reals assert S.Reals - FiniteSet(-I, I) == S.Reals assert Interval(0, 10) - FiniteSet(-I, I) == Interval(0, 10) assert Interval(0, 10) - FiniteSet(1, I) == Union( Interval.Ropen(0, 1), Interval.Lopen(1, 10)) assert S.Reals - FiniteSet(1, 2 + I, x, y**2) == Complement( Union(Interval.open(-oo, 1), Interval.open(1, oo)), FiniteSet(x, y**2), evaluate=False) assert FiniteSet(1, 2, 3) - FiniteSet(2) == FiniteSet(1, 3) assert FiniteSet('ham', 'eggs') - FiniteSet('eggs') == FiniteSet('ham') assert FiniteSet(1, 2, 3, 4) - Interval(2, 10, True, False) == \ FiniteSet(1, 2) assert FiniteSet(1, 2, 3, 4) - S.EmptySet == FiniteSet(1, 2, 3, 4) assert Union(Interval(0, 2), FiniteSet(2, 3, 4)) - Interval(1, 3) == \ Union(Interval(0, 1, False, True), FiniteSet(4)) assert -1 in S.Reals - S.Naturals def test_Complement(): A = FiniteSet(1, 3, 4) B = FiniteSet(3, 4) C = Interval(1, 3) D = Interval(1, 2) assert Complement(A, B, evaluate=False).is_iterable is True assert Complement(A, C, evaluate=False).is_iterable is True assert Complement(C, D, evaluate=False).is_iterable is None assert FiniteSet(*Complement(A, B, evaluate=False)) == FiniteSet(1) assert FiniteSet(*Complement(A, C, evaluate=False)) == FiniteSet(4) raises(TypeError, lambda: FiniteSet(*Complement(C, A, evaluate=False))) assert Complement(Interval(1, 3), Interval(1, 2)) == Interval(2, 3, True) assert Complement(FiniteSet(1, 3, 4), FiniteSet(3, 4)) == FiniteSet(1) assert Complement(Union(Interval(0, 2), FiniteSet(2, 3, 4)), Interval(1, 3)) == \ Union(Interval(0, 1, False, True), FiniteSet(4)) assert not 3 in Complement(Interval(0, 5), Interval(1, 4), evaluate=False) assert -1 in Complement(S.Reals, S.Naturals, evaluate=False) assert not 1 in Complement(S.Reals, S.Naturals, evaluate=False) assert Complement(S.Integers, S.UniversalSet) == EmptySet assert S.UniversalSet.complement(S.Integers) == EmptySet assert (not 0 in S.Reals.intersect(S.Integers - FiniteSet(0))) assert S.EmptySet - S.Integers == S.EmptySet assert (S.Integers - FiniteSet(0)) - FiniteSet(1) == S.Integers - FiniteSet(0, 1) assert S.Reals - Union(S.Naturals, FiniteSet(pi)) == \ Intersection(S.Reals - S.Naturals, S.Reals - FiniteSet(pi)) # issue 12712 assert Complement(FiniteSet(x, y, 2), Interval(-10, 10)) == \ Complement(FiniteSet(x, y), Interval(-10, 10)) A = FiniteSet(*symbols('a:c')) B = FiniteSet(*symbols('d:f')) assert unchanged(Complement, ProductSet(A, A), B) A2 = ProductSet(A, A) B3 = ProductSet(B, B, B) assert A2 - B3 == A2 assert B3 - A2 == B3 def test_set_operations_nonsets(): '''Tests that e.g. FiniteSet(1) * 2 raises TypeError''' ops = [ lambda a, b: a + b, lambda a, b: a - b, lambda a, b: a * b, lambda a, b: a / b, lambda a, b: a // b, lambda a, b: a | b, lambda a, b: a & b, lambda a, b: a ^ b, # FiniteSet(1) ** 2 gives a ProductSet #lambda a, b: a ** b, ] Sx = FiniteSet(x) Sy = FiniteSet(y) sets = [ {1}, FiniteSet(1), Interval(1, 2), Union(Sx, Interval(1, 2)), Intersection(Sx, Sy), Complement(Sx, Sy), ProductSet(Sx, Sy), S.EmptySet, ] nums = [0, 1, 2, S(0), S(1), S(2)] for si in sets: for ni in nums: for op in ops: raises(TypeError, lambda : op(si, ni)) raises(TypeError, lambda : op(ni, si)) raises(TypeError, lambda: si ** object()) raises(TypeError, lambda: si ** {1}) def test_complement(): assert Interval(0, 1).complement(S.Reals) == \ Union(Interval(-oo, 0, True, True), Interval(1, oo, True, True)) assert Interval(0, 1, True, False).complement(S.Reals) == \ Union(Interval(-oo, 0, True, False), Interval(1, oo, True, True)) assert Interval(0, 1, False, True).complement(S.Reals) == \ Union(Interval(-oo, 0, True, True), Interval(1, oo, False, True)) assert Interval(0, 1, True, True).complement(S.Reals) == \ Union(Interval(-oo, 0, True, False), Interval(1, oo, False, True)) assert S.UniversalSet.complement(S.EmptySet) == S.EmptySet assert S.UniversalSet.complement(S.Reals) == S.EmptySet assert S.UniversalSet.complement(S.UniversalSet) == S.EmptySet assert S.EmptySet.complement(S.Reals) == S.Reals assert Union(Interval(0, 1), Interval(2, 3)).complement(S.Reals) == \ Union(Interval(-oo, 0, True, True), Interval(1, 2, True, True), Interval(3, oo, True, True)) assert FiniteSet(0).complement(S.Reals) == \ Union(Interval(-oo, 0, True, True), Interval(0, oo, True, True)) assert (FiniteSet(5) + Interval(S.NegativeInfinity, 0)).complement(S.Reals) == \ Interval(0, 5, True, True) + Interval(5, S.Infinity, True, True) assert FiniteSet(1, 2, 3).complement(S.Reals) == \ Interval(S.NegativeInfinity, 1, True, True) + \ Interval(1, 2, True, True) + Interval(2, 3, True, True) +\ Interval(3, S.Infinity, True, True) assert FiniteSet(x).complement(S.Reals) == Complement(S.Reals, FiniteSet(x)) assert FiniteSet(0, x).complement(S.Reals) == Complement(Interval(-oo, 0, True, True) + Interval(0, oo, True, True) , FiniteSet(x), evaluate=False) square = Interval(0, 1) * Interval(0, 1) notsquare = square.complement(S.Reals*S.Reals) assert all(pt in square for pt in [(0, 0), (.5, .5), (1, 0), (1, 1)]) assert not any( pt in notsquare for pt in [(0, 0), (.5, .5), (1, 0), (1, 1)]) assert not any(pt in square for pt in [(-1, 0), (1.5, .5), (10, 10)]) assert all(pt in notsquare for pt in [(-1, 0), (1.5, .5), (10, 10)]) def test_intersect1(): assert all(S.Integers.intersection(i) is i for i in (S.Naturals, S.Naturals0)) assert all(i.intersection(S.Integers) is i for i in (S.Naturals, S.Naturals0)) s = S.Naturals0 assert S.Naturals.intersection(s) is S.Naturals assert s.intersection(S.Naturals) is S.Naturals x = Symbol('x') assert Interval(0, 2).intersect(Interval(1, 2)) == Interval(1, 2) assert Interval(0, 2).intersect(Interval(1, 2, True)) == \ Interval(1, 2, True) assert Interval(0, 2, True).intersect(Interval(1, 2)) == \ Interval(1, 2, False, False) assert Interval(0, 2, True, True).intersect(Interval(1, 2)) == \ Interval(1, 2, False, True) assert Interval(0, 2).intersect(Union(Interval(0, 1), Interval(2, 3))) == \ Union(Interval(0, 1), Interval(2, 2)) assert FiniteSet(1, 2).intersect(FiniteSet(1, 2, 3)) == FiniteSet(1, 2) assert FiniteSet(1, 2, x).intersect(FiniteSet(x)) == FiniteSet(x) assert FiniteSet('ham', 'eggs').intersect(FiniteSet('ham')) == \ FiniteSet('ham') assert FiniteSet(1, 2, 3, 4, 5).intersect(S.EmptySet) == S.EmptySet assert Interval(0, 5).intersect(FiniteSet(1, 3)) == FiniteSet(1, 3) assert Interval(0, 1, True, True).intersect(FiniteSet(1)) == S.EmptySet assert Union(Interval(0, 1), Interval(2, 3)).intersect(Interval(1, 2)) == \ Union(Interval(1, 1), Interval(2, 2)) assert Union(Interval(0, 1), Interval(2, 3)).intersect(Interval(0, 2)) == \ Union(Interval(0, 1), Interval(2, 2)) assert Union(Interval(0, 1), Interval(2, 3)).intersect(Interval(1, 2, True, True)) == \ S.EmptySet assert Union(Interval(0, 1), Interval(2, 3)).intersect(S.EmptySet) == \ S.EmptySet assert Union(Interval(0, 5), FiniteSet('ham')).intersect(FiniteSet(2, 3, 4, 5, 6)) == \ Intersection(FiniteSet(2, 3, 4, 5, 6), Union(FiniteSet('ham'), Interval(0, 5))) assert Intersection(FiniteSet(1, 2, 3), Interval(2, x), Interval(3, y)) == \ Intersection(FiniteSet(3), Interval(2, x), Interval(3, y), evaluate=False) assert Intersection(FiniteSet(1, 2), Interval(0, 3), Interval(x, y)) == \ Intersection({1, 2}, Interval(x, y), evaluate=False) assert Intersection(FiniteSet(1, 2, 4), Interval(0, 3), Interval(x, y)) == \ Intersection({1, 2}, Interval(x, y), evaluate=False) # XXX: Is the real=True necessary here? # https://github.com/sympy/sympy/issues/17532 m, n = symbols('m, n', real=True) assert Intersection(FiniteSet(m), FiniteSet(m, n), Interval(m, m+1)) == \ FiniteSet(m) # issue 8217 assert Intersection(FiniteSet(x), FiniteSet(y)) == \ Intersection(FiniteSet(x), FiniteSet(y), evaluate=False) assert FiniteSet(x).intersect(S.Reals) == \ Intersection(S.Reals, FiniteSet(x), evaluate=False) # tests for the intersection alias assert Interval(0, 5).intersection(FiniteSet(1, 3)) == FiniteSet(1, 3) assert Interval(0, 1, True, True).intersection(FiniteSet(1)) == S.EmptySet assert Union(Interval(0, 1), Interval(2, 3)).intersection(Interval(1, 2)) == \ Union(Interval(1, 1), Interval(2, 2)) def test_intersection(): # iterable i = Intersection(FiniteSet(1, 2, 3), Interval(2, 5), evaluate=False) assert i.is_iterable assert set(i) == {S(2), S(3)} # challenging intervals x = Symbol('x', real=True) i = Intersection(Interval(0, 3), Interval(x, 6)) assert (5 in i) is False raises(TypeError, lambda: 2 in i) # Singleton special cases assert Intersection(Interval(0, 1), S.EmptySet) == S.EmptySet assert Intersection(Interval(-oo, oo), Interval(-oo, x)) == Interval(-oo, x) # Products line = Interval(0, 5) i = Intersection(line**2, line**3, evaluate=False) assert (2, 2) not in i assert (2, 2, 2) not in i raises(TypeError, lambda: list(i)) a = Intersection(Intersection(S.Integers, S.Naturals, evaluate=False), S.Reals, evaluate=False) assert a._argset == frozenset([Intersection(S.Naturals, S.Integers, evaluate=False), S.Reals]) assert Intersection(S.Complexes, FiniteSet(S.ComplexInfinity)) == S.EmptySet # issue 12178 assert Intersection() == S.UniversalSet # issue 16987 assert Intersection({1}, {1}, {x}) == Intersection({1}, {x}) def test_issue_9623(): n = Symbol('n') a = S.Reals b = Interval(0, oo) c = FiniteSet(n) assert Intersection(a, b, c) == Intersection(b, c) assert Intersection(Interval(1, 2), Interval(3, 4), FiniteSet(n)) == EmptySet def test_is_disjoint(): assert Interval(0, 2).is_disjoint(Interval(1, 2)) == False assert Interval(0, 2).is_disjoint(Interval(3, 4)) == True def test_ProductSet__len__(): A = FiniteSet(1, 2) B = FiniteSet(1, 2, 3) assert ProductSet(A).__len__() == 2 assert ProductSet(A).__len__() is not S(2) assert ProductSet(A, B).__len__() == 6 assert ProductSet(A, B).__len__() is not S(6) def test_ProductSet(): # ProductSet is always a set of Tuples assert ProductSet(S.Reals) == S.Reals ** 1 assert ProductSet(S.Reals, S.Reals) == S.Reals ** 2 assert ProductSet(S.Reals, S.Reals, S.Reals) == S.Reals ** 3 assert ProductSet(S.Reals) != S.Reals assert ProductSet(S.Reals, S.Reals) == S.Reals * S.Reals assert ProductSet(S.Reals, S.Reals, S.Reals) != S.Reals * S.Reals * S.Reals assert ProductSet(S.Reals, S.Reals, S.Reals) == (S.Reals * S.Reals * S.Reals).flatten() assert 1 not in ProductSet(S.Reals) assert (1,) in ProductSet(S.Reals) assert 1 not in ProductSet(S.Reals, S.Reals) assert (1, 2) in ProductSet(S.Reals, S.Reals) assert (1, I) not in ProductSet(S.Reals, S.Reals) assert (1, 2, 3) in ProductSet(S.Reals, S.Reals, S.Reals) assert (1, 2, 3) in S.Reals ** 3 assert (1, 2, 3) not in S.Reals * S.Reals * S.Reals assert ((1, 2), 3) in S.Reals * S.Reals * S.Reals assert (1, (2, 3)) not in S.Reals * S.Reals * S.Reals assert (1, (2, 3)) in S.Reals * (S.Reals * S.Reals) assert ProductSet() == FiniteSet(()) assert ProductSet(S.Reals, S.EmptySet) == S.EmptySet # See GH-17458 for ni in range(5): Rn = ProductSet(*(S.Reals,) * ni) assert (1,) * ni in Rn assert 1 not in Rn assert (S.Reals * S.Reals) * S.Reals != S.Reals * (S.Reals * S.Reals) S1 = S.Reals S2 = S.Integers x1 = pi x2 = 3 assert x1 in S1 assert x2 in S2 assert (x1, x2) in S1 * S2 S3 = S1 * S2 x3 = (x1, x2) assert x3 in S3 assert (x3, x3) in S3 * S3 assert x3 + x3 not in S3 * S3 raises(ValueError, lambda: S.Reals**-1) with warns_deprecated_sympy(): ProductSet(FiniteSet(s) for s in range(2)) raises(TypeError, lambda: ProductSet(None)) S1 = FiniteSet(1, 2) S2 = FiniteSet(3, 4) S3 = ProductSet(S1, S2) assert (S3.as_relational(x, y) == And(S1.as_relational(x), S2.as_relational(y)) == And(Or(Eq(x, 1), Eq(x, 2)), Or(Eq(y, 3), Eq(y, 4)))) raises(ValueError, lambda: S3.as_relational(x)) raises(ValueError, lambda: S3.as_relational(x, 1)) raises(ValueError, lambda: ProductSet(Interval(0, 1)).as_relational(x, y)) Z2 = ProductSet(S.Integers, S.Integers) assert Z2.contains((1, 2)) is S.true assert Z2.contains((1,)) is S.false assert Z2.contains(x) == Contains(x, Z2, evaluate=False) assert Z2.contains(x).subs(x, 1) is S.false assert Z2.contains((x, 1)).subs(x, 2) is S.true assert Z2.contains((x, y)) == Contains((x, y), Z2, evaluate=False) assert unchanged(Contains, (x, y), Z2) assert Contains((1, 2), Z2) is S.true def test_ProductSet_of_single_arg_is_not_arg(): assert unchanged(ProductSet, Interval(0, 1)) assert unchanged(ProductSet, ProductSet(Interval(0, 1))) def test_ProductSet_is_empty(): assert ProductSet(S.Integers, S.Reals).is_empty == False assert ProductSet(Interval(x, 1), S.Reals).is_empty == None def test_interval_subs(): a = Symbol('a', real=True) assert Interval(0, a).subs(a, 2) == Interval(0, 2) assert Interval(a, 0).subs(a, 2) == S.EmptySet def test_interval_to_mpi(): assert Interval(0, 1).to_mpi() == mpi(0, 1) assert Interval(0, 1, True, False).to_mpi() == mpi(0, 1) assert type(Interval(0, 1).to_mpi()) == type(mpi(0, 1)) def test_set_evalf(): assert Interval(S(11)/64, S.Half).evalf() == Interval( Float('0.171875'), Float('0.5')) assert Interval(x, S.Half, right_open=True).evalf() == Interval( x, Float('0.5'), right_open=True) assert Interval(-oo, S.Half).evalf() == Interval(-oo, Float('0.5')) assert FiniteSet(2, x).evalf() == FiniteSet(Float('2.0'), x) def test_measure(): a = Symbol('a', real=True) assert Interval(1, 3).measure == 2 assert Interval(0, a).measure == a assert Interval(1, a).measure == a - 1 assert Union(Interval(1, 2), Interval(3, 4)).measure == 2 assert Union(Interval(1, 2), Interval(3, 4), FiniteSet(5, 6, 7)).measure \ == 2 assert FiniteSet(1, 2, oo, a, -oo, -5).measure == 0 assert S.EmptySet.measure == 0 square = Interval(0, 10) * Interval(0, 10) offsetsquare = Interval(5, 15) * Interval(5, 15) band = Interval(-oo, oo) * Interval(2, 4) assert square.measure == offsetsquare.measure == 100 assert (square + offsetsquare).measure == 175 # there is some overlap assert (square - offsetsquare).measure == 75 assert (square * FiniteSet(1, 2, 3)).measure == 0 assert (square.intersect(band)).measure == 20 assert (square + band).measure is oo assert (band * FiniteSet(1, 2, 3)).measure is nan def test_is_subset(): assert Interval(0, 1).is_subset(Interval(0, 2)) is True assert Interval(0, 3).is_subset(Interval(0, 2)) is False assert Interval(0, 1).is_subset(FiniteSet(0, 1)) is False assert FiniteSet(1, 2).is_subset(FiniteSet(1, 2, 3, 4)) assert FiniteSet(4, 5).is_subset(FiniteSet(1, 2, 3, 4)) is False assert FiniteSet(1).is_subset(Interval(0, 2)) assert FiniteSet(1, 2).is_subset(Interval(0, 2, True, True)) is False assert (Interval(1, 2) + FiniteSet(3)).is_subset( Interval(0, 2, False, True) + FiniteSet(2, 3)) assert Interval(3, 4).is_subset(Union(Interval(0, 1), Interval(2, 5))) is True assert Interval(3, 6).is_subset(Union(Interval(0, 1), Interval(2, 5))) is False assert FiniteSet(1, 2, 3, 4).is_subset(Interval(0, 5)) is True assert S.EmptySet.is_subset(FiniteSet(1, 2, 3)) is True assert Interval(0, 1).is_subset(S.EmptySet) is False assert S.EmptySet.is_subset(S.EmptySet) is True raises(ValueError, lambda: S.EmptySet.is_subset(1)) # tests for the issubset alias assert FiniteSet(1, 2, 3, 4).issubset(Interval(0, 5)) is True assert S.EmptySet.issubset(FiniteSet(1, 2, 3)) is True assert S.Naturals.is_subset(S.Integers) assert S.Naturals0.is_subset(S.Integers) assert FiniteSet(x).is_subset(FiniteSet(y)) is None assert FiniteSet(x).is_subset(FiniteSet(y).subs(y, x)) is True assert FiniteSet(x).is_subset(FiniteSet(y).subs(y, x+1)) is False assert Interval(0, 1).is_subset(Interval(0, 1, left_open=True)) is False assert Interval(-2, 3).is_subset(Union(Interval(-oo, -2), Interval(3, oo))) is False n = Symbol('n', integer=True) assert Range(-3, 4, 1).is_subset(FiniteSet(-10, 10)) is False assert Range(S(10)**100).is_subset(FiniteSet(0, 1, 2)) is False assert Range(6, 0, -2).is_subset(FiniteSet(2, 4, 6)) is True assert Range(1, oo).is_subset(FiniteSet(1, 2)) is False assert Range(-oo, 1).is_subset(FiniteSet(1)) is False assert Range(3).is_subset(FiniteSet(0, 1, n)) is None assert Range(n, n + 2).is_subset(FiniteSet(n, n + 1)) is True assert Range(5).is_subset(Interval(0, 4, right_open=True)) is False #issue 19513 assert imageset(Lambda(n, 1/n), S.Integers).is_subset(S.Reals) is None def test_is_proper_subset(): assert Interval(0, 1).is_proper_subset(Interval(0, 2)) is True assert Interval(0, 3).is_proper_subset(Interval(0, 2)) is False assert S.EmptySet.is_proper_subset(FiniteSet(1, 2, 3)) is True raises(ValueError, lambda: Interval(0, 1).is_proper_subset(0)) def test_is_superset(): assert Interval(0, 1).is_superset(Interval(0, 2)) == False assert Interval(0, 3).is_superset(Interval(0, 2)) assert FiniteSet(1, 2).is_superset(FiniteSet(1, 2, 3, 4)) == False assert FiniteSet(4, 5).is_superset(FiniteSet(1, 2, 3, 4)) == False assert FiniteSet(1).is_superset(Interval(0, 2)) == False assert FiniteSet(1, 2).is_superset(Interval(0, 2, True, True)) == False assert (Interval(1, 2) + FiniteSet(3)).is_superset( Interval(0, 2, False, True) + FiniteSet(2, 3)) == False assert Interval(3, 4).is_superset(Union(Interval(0, 1), Interval(2, 5))) == False assert FiniteSet(1, 2, 3, 4).is_superset(Interval(0, 5)) == False assert S.EmptySet.is_superset(FiniteSet(1, 2, 3)) == False assert Interval(0, 1).is_superset(S.EmptySet) == True assert S.EmptySet.is_superset(S.EmptySet) == True raises(ValueError, lambda: S.EmptySet.is_superset(1)) # tests for the issuperset alias assert Interval(0, 1).issuperset(S.EmptySet) == True assert S.EmptySet.issuperset(S.EmptySet) == True def test_is_proper_superset(): assert Interval(0, 1).is_proper_superset(Interval(0, 2)) is False assert Interval(0, 3).is_proper_superset(Interval(0, 2)) is True assert FiniteSet(1, 2, 3).is_proper_superset(S.EmptySet) is True raises(ValueError, lambda: Interval(0, 1).is_proper_superset(0)) def test_contains(): assert Interval(0, 2).contains(1) is S.true assert Interval(0, 2).contains(3) is S.false assert Interval(0, 2, True, False).contains(0) is S.false assert Interval(0, 2, True, False).contains(2) is S.true assert Interval(0, 2, False, True).contains(0) is S.true assert Interval(0, 2, False, True).contains(2) is S.false assert Interval(0, 2, True, True).contains(0) is S.false assert Interval(0, 2, True, True).contains(2) is S.false assert (Interval(0, 2) in Interval(0, 2)) is False assert FiniteSet(1, 2, 3).contains(2) is S.true assert FiniteSet(1, 2, Symbol('x')).contains(Symbol('x')) is S.true assert FiniteSet(y)._contains(x) is None raises(TypeError, lambda: x in FiniteSet(y)) assert FiniteSet({x, y})._contains({x}) is None assert FiniteSet({x, y}).subs(y, x)._contains({x}) is True assert FiniteSet({x, y}).subs(y, x+1)._contains({x}) is False # issue 8197 from sympy.abc import a, b assert isinstance(FiniteSet(b).contains(-a), Contains) assert isinstance(FiniteSet(b).contains(a), Contains) assert isinstance(FiniteSet(a).contains(1), Contains) raises(TypeError, lambda: 1 in FiniteSet(a)) # issue 8209 rad1 = Pow(Pow(2, Rational(1, 3)) - 1, Rational(1, 3)) rad2 = Pow(Rational(1, 9), Rational(1, 3)) - Pow(Rational(2, 9), Rational(1, 3)) + Pow(Rational(4, 9), Rational(1, 3)) s1 = FiniteSet(rad1) s2 = FiniteSet(rad2) assert s1 - s2 == S.EmptySet items = [1, 2, S.Infinity, S('ham'), -1.1] fset = FiniteSet(*items) assert all(item in fset for item in items) assert all(fset.contains(item) is S.true for item in items) assert Union(Interval(0, 1), Interval(2, 5)).contains(3) is S.true assert Union(Interval(0, 1), Interval(2, 5)).contains(6) is S.false assert Union(Interval(0, 1), FiniteSet(2, 5)).contains(3) is S.false assert S.EmptySet.contains(1) is S.false assert FiniteSet(rootof(x**3 + x - 1, 0)).contains(S.Infinity) is S.false assert rootof(x**5 + x**3 + 1, 0) in S.Reals assert not rootof(x**5 + x**3 + 1, 1) in S.Reals # non-bool results assert Union(Interval(1, 2), Interval(3, 4)).contains(x) == \ Or(And(S.One <= x, x <= 2), And(S(3) <= x, x <= 4)) assert Intersection(Interval(1, x), Interval(2, 3)).contains(y) == \ And(y <= 3, y <= x, S.One <= y, S(2) <= y) assert (S.Complexes).contains(S.ComplexInfinity) == S.false def test_interval_symbolic(): x = Symbol('x') e = Interval(0, 1) assert e.contains(x) == And(S.Zero <= x, x <= 1) raises(TypeError, lambda: x in e) e = Interval(0, 1, True, True) assert e.contains(x) == And(S.Zero < x, x < 1) c = Symbol('c', real=False) assert Interval(x, x + 1).contains(c) == False e = Symbol('e', extended_real=True) assert Interval(-oo, oo).contains(e) == And( S.NegativeInfinity < e, e < S.Infinity) def test_union_contains(): x = Symbol('x') i1 = Interval(0, 1) i2 = Interval(2, 3) i3 = Union(i1, i2) assert i3.as_relational(x) == Or(And(S.Zero <= x, x <= 1), And(S(2) <= x, x <= 3)) raises(TypeError, lambda: x in i3) e = i3.contains(x) assert e == i3.as_relational(x) assert e.subs(x, -0.5) is false assert e.subs(x, 0.5) is true assert e.subs(x, 1.5) is false assert e.subs(x, 2.5) is true assert e.subs(x, 3.5) is false U = Interval(0, 2, True, True) + Interval(10, oo) + FiniteSet(-1, 2, 5, 6) assert all(el not in U for el in [0, 4, -oo]) assert all(el in U for el in [2, 5, 10]) def test_is_number(): assert Interval(0, 1).is_number is False assert Set().is_number is False def test_Interval_is_left_unbounded(): assert Interval(3, 4).is_left_unbounded is False assert Interval(-oo, 3).is_left_unbounded is True assert Interval(Float("-inf"), 3).is_left_unbounded is True def test_Interval_is_right_unbounded(): assert Interval(3, 4).is_right_unbounded is False assert Interval(3, oo).is_right_unbounded is True assert Interval(3, Float("+inf")).is_right_unbounded is True def test_Interval_as_relational(): x = Symbol('x') assert Interval(-1, 2, False, False).as_relational(x) == \ And(Le(-1, x), Le(x, 2)) assert Interval(-1, 2, True, False).as_relational(x) == \ And(Lt(-1, x), Le(x, 2)) assert Interval(-1, 2, False, True).as_relational(x) == \ And(Le(-1, x), Lt(x, 2)) assert Interval(-1, 2, True, True).as_relational(x) == \ And(Lt(-1, x), Lt(x, 2)) assert Interval(-oo, 2, right_open=False).as_relational(x) == And(Lt(-oo, x), Le(x, 2)) assert Interval(-oo, 2, right_open=True).as_relational(x) == And(Lt(-oo, x), Lt(x, 2)) assert Interval(-2, oo, left_open=False).as_relational(x) == And(Le(-2, x), Lt(x, oo)) assert Interval(-2, oo, left_open=True).as_relational(x) == And(Lt(-2, x), Lt(x, oo)) assert Interval(-oo, oo).as_relational(x) == And(Lt(-oo, x), Lt(x, oo)) x = Symbol('x', real=True) y = Symbol('y', real=True) assert Interval(x, y).as_relational(x) == (x <= y) assert Interval(y, x).as_relational(x) == (y <= x) def test_Finite_as_relational(): x = Symbol('x') y = Symbol('y') assert FiniteSet(1, 2).as_relational(x) == Or(Eq(x, 1), Eq(x, 2)) assert FiniteSet(y, -5).as_relational(x) == Or(Eq(x, y), Eq(x, -5)) def test_Union_as_relational(): x = Symbol('x') assert (Interval(0, 1) + FiniteSet(2)).as_relational(x) == \ Or(And(Le(0, x), Le(x, 1)), Eq(x, 2)) assert (Interval(0, 1, True, True) + FiniteSet(1)).as_relational(x) == \ And(Lt(0, x), Le(x, 1)) assert Or(x < 0, x > 0).as_set().as_relational(x) == \ And((x > -oo), (x < oo), Ne(x, 0)) assert (Interval.Ropen(1, 3) + Interval.Lopen(3, 5) ).as_relational(x) == And((x > 1), (x < 5), Ne(x, 3)) def test_Intersection_as_relational(): x = Symbol('x') assert (Intersection(Interval(0, 1), FiniteSet(2), evaluate=False).as_relational(x) == And(And(Le(0, x), Le(x, 1)), Eq(x, 2))) def test_Complement_as_relational(): x = Symbol('x') expr = Complement(Interval(0, 1), FiniteSet(2), evaluate=False) assert expr.as_relational(x) == \ And(Le(0, x), Le(x, 1), Ne(x, 2)) @XFAIL def test_Complement_as_relational_fail(): x = Symbol('x') expr = Complement(Interval(0, 1), FiniteSet(2), evaluate=False) # XXX This example fails because 0 <= x changes to x >= 0 # during the evaluation. assert expr.as_relational(x) == \ (0 <= x) & (x <= 1) & Ne(x, 2) def test_SymmetricDifference_as_relational(): x = Symbol('x') expr = SymmetricDifference(Interval(0, 1), FiniteSet(2), evaluate=False) assert expr.as_relational(x) == Xor(Eq(x, 2), Le(0, x) & Le(x, 1)) def test_EmptySet(): assert S.EmptySet.as_relational(Symbol('x')) is S.false assert S.EmptySet.intersect(S.UniversalSet) == S.EmptySet assert S.EmptySet.boundary == S.EmptySet def test_finite_basic(): x = Symbol('x') A = FiniteSet(1, 2, 3) B = FiniteSet(3, 4, 5) AorB = Union(A, B) AandB = A.intersect(B) assert A.is_subset(AorB) and B.is_subset(AorB) assert AandB.is_subset(A) assert AandB == FiniteSet(3) assert A.inf == 1 and A.sup == 3 assert AorB.inf == 1 and AorB.sup == 5 assert FiniteSet(x, 1, 5).sup == Max(x, 5) assert FiniteSet(x, 1, 5).inf == Min(x, 1) # issue 7335 assert FiniteSet(S.EmptySet) != S.EmptySet assert FiniteSet(FiniteSet(1, 2, 3)) != FiniteSet(1, 2, 3) assert FiniteSet((1, 2, 3)) != FiniteSet(1, 2, 3) # Ensure a variety of types can exist in a FiniteSet assert FiniteSet((1, 2), Float, A, -5, x, 'eggs', x**2, Interval) assert (A > B) is False assert (A >= B) is False assert (A < B) is False assert (A <= B) is False assert AorB > A and AorB > B assert AorB >= A and AorB >= B assert A >= A and A <= A assert A >= AandB and B >= AandB assert A > AandB and B > AandB assert FiniteSet(1.0) == FiniteSet(1) def test_product_basic(): H, T = 'H', 'T' unit_line = Interval(0, 1) d6 = FiniteSet(1, 2, 3, 4, 5, 6) d4 = FiniteSet(1, 2, 3, 4) coin = FiniteSet(H, T) square = unit_line * unit_line assert (0, 0) in square assert 0 not in square assert (H, T) in coin ** 2 assert (.5, .5, .5) in (square * unit_line).flatten() assert ((.5, .5), .5) in square * unit_line assert (H, 3, 3) in (coin * d6 * d6).flatten() assert ((H, 3), 3) in coin * d6 * d6 HH, TT = sympify(H), sympify(T) assert set(coin**2) == {(HH, HH), (HH, TT), (TT, HH), (TT, TT)} assert (d4*d4).is_subset(d6*d6) assert square.complement(Interval(-oo, oo)*Interval(-oo, oo)) == Union( (Interval(-oo, 0, True, True) + Interval(1, oo, True, True))*Interval(-oo, oo), Interval(-oo, oo)*(Interval(-oo, 0, True, True) + Interval(1, oo, True, True))) assert (Interval(-5, 5)**3).is_subset(Interval(-10, 10)**3) assert not (Interval(-10, 10)**3).is_subset(Interval(-5, 5)**3) assert not (Interval(-5, 5)**2).is_subset(Interval(-10, 10)**3) assert (Interval(.2, .5)*FiniteSet(.5)).is_subset(square) # segment in square assert len(coin*coin*coin) == 8 assert len(S.EmptySet*S.EmptySet) == 0 assert len(S.EmptySet*coin) == 0 raises(TypeError, lambda: len(coin*Interval(0, 2))) def test_real(): x = Symbol('x', real=True, finite=True) I = Interval(0, 5) J = Interval(10, 20) A = FiniteSet(1, 2, 30, x, S.Pi) B = FiniteSet(-4, 0) C = FiniteSet(100) D = FiniteSet('Ham', 'Eggs') assert all(s.is_subset(S.Reals) for s in [I, J, A, B, C]) assert not D.is_subset(S.Reals) assert all((a + b).is_subset(S.Reals) for a in [I, J, A, B, C] for b in [I, J, A, B, C]) assert not any((a + D).is_subset(S.Reals) for a in [I, J, A, B, C, D]) assert not (I + A + D).is_subset(S.Reals) def test_supinf(): x = Symbol('x', real=True) y = Symbol('y', real=True) assert (Interval(0, 1) + FiniteSet(2)).sup == 2 assert (Interval(0, 1) + FiniteSet(2)).inf == 0 assert (Interval(0, 1) + FiniteSet(x)).sup == Max(1, x) assert (Interval(0, 1) + FiniteSet(x)).inf == Min(0, x) assert FiniteSet(5, 1, x).sup == Max(5, x) assert FiniteSet(5, 1, x).inf == Min(1, x) assert FiniteSet(5, 1, x, y).sup == Max(5, x, y) assert FiniteSet(5, 1, x, y).inf == Min(1, x, y) assert FiniteSet(5, 1, x, y, S.Infinity, S.NegativeInfinity).sup == \ S.Infinity assert FiniteSet(5, 1, x, y, S.Infinity, S.NegativeInfinity).inf == \ S.NegativeInfinity assert FiniteSet('Ham', 'Eggs').sup == Max('Ham', 'Eggs') def test_universalset(): U = S.UniversalSet x = Symbol('x') assert U.as_relational(x) is S.true assert U.union(Interval(2, 4)) == U assert U.intersect(Interval(2, 4)) == Interval(2, 4) assert U.measure is S.Infinity assert U.boundary == S.EmptySet assert U.contains(0) is S.true def test_Union_of_ProductSets_shares(): line = Interval(0, 2) points = FiniteSet(0, 1, 2) assert Union(line * line, line * points) == line * line def test_Interval_free_symbols(): # issue 6211 assert Interval(0, 1).free_symbols == set() x = Symbol('x', real=True) assert Interval(0, x).free_symbols == {x} def test_image_interval(): from sympy.core.numbers import Rational x = Symbol('x', real=True) a = Symbol('a', real=True) assert imageset(x, 2*x, Interval(-2, 1)) == Interval(-4, 2) assert imageset(x, 2*x, Interval(-2, 1, True, False)) == \ Interval(-4, 2, True, False) assert imageset(x, x**2, Interval(-2, 1, True, False)) == \ Interval(0, 4, False, True) assert imageset(x, x**2, Interval(-2, 1)) == Interval(0, 4) assert imageset(x, x**2, Interval(-2, 1, True, False)) == \ Interval(0, 4, False, True) assert imageset(x, x**2, Interval(-2, 1, True, True)) == \ Interval(0, 4, False, True) assert imageset(x, (x - 2)**2, Interval(1, 3)) == Interval(0, 1) assert imageset(x, 3*x**4 - 26*x**3 + 78*x**2 - 90*x, Interval(0, 4)) == \ Interval(-35, 0) # Multiple Maxima assert imageset(x, x + 1/x, Interval(-oo, oo)) == Interval(-oo, -2) \ + Interval(2, oo) # Single Infinite discontinuity assert imageset(x, 1/x + 1/(x-1)**2, Interval(0, 2, True, False)) == \ Interval(Rational(3, 2), oo, False) # Multiple Infinite discontinuities # Test for Python lambda assert imageset(lambda x: 2*x, Interval(-2, 1)) == Interval(-4, 2) assert imageset(Lambda(x, a*x), Interval(0, 1)) == \ ImageSet(Lambda(x, a*x), Interval(0, 1)) assert imageset(Lambda(x, sin(cos(x))), Interval(0, 1)) == \ ImageSet(Lambda(x, sin(cos(x))), Interval(0, 1)) def test_image_piecewise(): f = Piecewise((x, x <= -1), (1/x**2, x <= 5), (x**3, True)) f1 = Piecewise((0, x <= 1), (1, x <= 2), (2, True)) assert imageset(x, f, Interval(-5, 5)) == Union(Interval(-5, -1), Interval(Rational(1, 25), oo)) assert imageset(x, f1, Interval(1, 2)) == FiniteSet(0, 1) @XFAIL # See: https://github.com/sympy/sympy/pull/2723#discussion_r8659826 def test_image_Intersection(): x = Symbol('x', real=True) y = Symbol('y', real=True) assert imageset(x, x**2, Interval(-2, 0).intersect(Interval(x, y))) == \ Interval(0, 4).intersect(Interval(Min(x**2, y**2), Max(x**2, y**2))) def test_image_FiniteSet(): x = Symbol('x', real=True) assert imageset(x, 2*x, FiniteSet(1, 2, 3)) == FiniteSet(2, 4, 6) def test_image_Union(): x = Symbol('x', real=True) assert imageset(x, x**2, Interval(-2, 0) + FiniteSet(1, 2, 3)) == \ (Interval(0, 4) + FiniteSet(9)) def test_image_EmptySet(): x = Symbol('x', real=True) assert imageset(x, 2*x, S.EmptySet) == S.EmptySet def test_issue_5724_7680(): assert I not in S.Reals # issue 7680 assert Interval(-oo, oo).contains(I) is S.false def test_boundary(): assert FiniteSet(1).boundary == FiniteSet(1) assert all(Interval(0, 1, left_open, right_open).boundary == FiniteSet(0, 1) for left_open in (true, false) for right_open in (true, false)) def test_boundary_Union(): assert (Interval(0, 1) + Interval(2, 3)).boundary == FiniteSet(0, 1, 2, 3) assert ((Interval(0, 1, False, True) + Interval(1, 2, True, False)).boundary == FiniteSet(0, 1, 2)) assert (Interval(0, 1) + FiniteSet(2)).boundary == FiniteSet(0, 1, 2) assert Union(Interval(0, 10), Interval(5, 15), evaluate=False).boundary \ == FiniteSet(0, 15) assert Union(Interval(0, 10), Interval(0, 1), evaluate=False).boundary \ == FiniteSet(0, 10) assert Union(Interval(0, 10, True, True), Interval(10, 15, True, True), evaluate=False).boundary \ == FiniteSet(0, 10, 15) @XFAIL def test_union_boundary_of_joining_sets(): """ Testing the boundary of unions is a hard problem """ assert Union(Interval(0, 10), Interval(10, 15), evaluate=False).boundary \ == FiniteSet(0, 15) def test_boundary_ProductSet(): open_square = Interval(0, 1, True, True) ** 2 assert open_square.boundary == (FiniteSet(0, 1) * Interval(0, 1) + Interval(0, 1) * FiniteSet(0, 1)) second_square = Interval(1, 2, True, True) * Interval(0, 1, True, True) assert (open_square + second_square).boundary == ( FiniteSet(0, 1) * Interval(0, 1) + FiniteSet(1, 2) * Interval(0, 1) + Interval(0, 1) * FiniteSet(0, 1) + Interval(1, 2) * FiniteSet(0, 1)) def test_boundary_ProductSet_line(): line_in_r2 = Interval(0, 1) * FiniteSet(0) assert line_in_r2.boundary == line_in_r2 def test_is_open(): assert Interval(0, 1, False, False).is_open is False assert Interval(0, 1, True, False).is_open is False assert Interval(0, 1, True, True).is_open is True assert FiniteSet(1, 2, 3).is_open is False def test_is_closed(): assert Interval(0, 1, False, False).is_closed is True assert Interval(0, 1, True, False).is_closed is False assert FiniteSet(1, 2, 3).is_closed is True def test_closure(): assert Interval(0, 1, False, True).closure == Interval(0, 1, False, False) def test_interior(): assert Interval(0, 1, False, True).interior == Interval(0, 1, True, True) def test_issue_7841(): raises(TypeError, lambda: x in S.Reals) def test_Eq(): assert Eq(Interval(0, 1), Interval(0, 1)) assert Eq(Interval(0, 1), Interval(0, 2)) == False s1 = FiniteSet(0, 1) s2 = FiniteSet(1, 2) assert Eq(s1, s1) assert Eq(s1, s2) == False assert Eq(s1*s2, s1*s2) assert Eq(s1*s2, s2*s1) == False assert unchanged(Eq, FiniteSet({x, y}), FiniteSet({x})) assert Eq(FiniteSet({x, y}).subs(y, x), FiniteSet({x})) is S.true assert Eq(FiniteSet({x, y}), FiniteSet({x})).subs(y, x) is S.true assert Eq(FiniteSet({x, y}).subs(y, x+1), FiniteSet({x})) is S.false assert Eq(FiniteSet({x, y}), FiniteSet({x})).subs(y, x+1) is S.false assert Eq(ProductSet({1}, {2}), Interval(1, 2)) is S.false assert Eq(ProductSet({1}), ProductSet({1}, {2})) is S.false assert Eq(FiniteSet(()), FiniteSet(1)) is S.false assert Eq(ProductSet(), FiniteSet(1)) is S.false i1 = Interval(0, 1) i2 = Interval(x, y) assert unchanged(Eq, ProductSet(i1, i1), ProductSet(i2, i2)) def test_SymmetricDifference(): A = FiniteSet(0, 1, 2, 3, 4, 5) B = FiniteSet(2, 4, 6, 8, 10) C = Interval(8, 10) assert SymmetricDifference(A, B, evaluate=False).is_iterable is True assert SymmetricDifference(A, C, evaluate=False).is_iterable is None assert FiniteSet(*SymmetricDifference(A, B, evaluate=False)) == \ FiniteSet(0, 1, 3, 5, 6, 8, 10) raises(TypeError, lambda: FiniteSet(*SymmetricDifference(A, C, evaluate=False))) assert SymmetricDifference(FiniteSet(0, 1, 2, 3, 4, 5), \ FiniteSet(2, 4, 6, 8, 10)) == FiniteSet(0, 1, 3, 5, 6, 8, 10) assert SymmetricDifference(FiniteSet(2, 3, 4), FiniteSet(2, 3 , 4 , 5)) \ == FiniteSet(5) assert FiniteSet(1, 2, 3, 4, 5) ^ FiniteSet(1, 2, 5, 6) == \ FiniteSet(3, 4, 6) assert Set(S(1), S(2) , S(3)) ^ Set(S(2), S(3), S(4)) == Union(Set(S(1), S(2), S(3)) - Set(S(2), S(3), S(4)), \ Set(S(2), S(3), S(4)) - Set(S(1), S(2), S(3))) assert Interval(0, 4) ^ Interval(2, 5) == Union(Interval(0, 4) - \ Interval(2, 5), Interval(2, 5) - Interval(0, 4)) def test_issue_9536(): from sympy.functions.elementary.exponential import log a = Symbol('a', real=True) assert FiniteSet(log(a)).intersect(S.Reals) == Intersection(S.Reals, FiniteSet(log(a))) def test_issue_9637(): n = Symbol('n') a = FiniteSet(n) b = FiniteSet(2, n) assert Complement(S.Reals, a) == Complement(S.Reals, a, evaluate=False) assert Complement(Interval(1, 3), a) == Complement(Interval(1, 3), a, evaluate=False) assert Complement(Interval(1, 3), b) == \ Complement(Union(Interval(1, 2, False, True), Interval(2, 3, True, False)), a) assert Complement(a, S.Reals) == Complement(a, S.Reals, evaluate=False) assert Complement(a, Interval(1, 3)) == Complement(a, Interval(1, 3), evaluate=False) def test_issue_9808(): # See https://github.com/sympy/sympy/issues/16342 assert Complement(FiniteSet(y), FiniteSet(1)) == Complement(FiniteSet(y), FiniteSet(1), evaluate=False) assert Complement(FiniteSet(1, 2, x), FiniteSet(x, y, 2, 3)) == \ Complement(FiniteSet(1), FiniteSet(y), evaluate=False) def test_issue_9956(): assert Union(Interval(-oo, oo), FiniteSet(1)) == Interval(-oo, oo) assert Interval(-oo, oo).contains(1) is S.true def test_issue_Symbol_inter(): i = Interval(0, oo) r = S.Reals mat = Matrix([0, 0, 0]) assert Intersection(r, i, FiniteSet(m), FiniteSet(m, n)) == \ Intersection(i, FiniteSet(m)) assert Intersection(FiniteSet(1, m, n), FiniteSet(m, n, 2), i) == \ Intersection(i, FiniteSet(m, n)) assert Intersection(FiniteSet(m, n, x), FiniteSet(m, z), r) == \ Intersection(Intersection({m, z}, {m, n, x}), r) assert Intersection(FiniteSet(m, n, 3), FiniteSet(m, n, x), r) == \ Intersection(FiniteSet(3, m, n), FiniteSet(m, n, x), r, evaluate=False) assert Intersection(FiniteSet(m, n, 3), FiniteSet(m, n, 2, 3), r) == \ Intersection(FiniteSet(3, m, n), r) assert Intersection(r, FiniteSet(mat, 2, n), FiniteSet(0, mat, n)) == \ Intersection(r, FiniteSet(n)) assert Intersection(FiniteSet(sin(x), cos(x)), FiniteSet(sin(x), cos(x), 1), r) == \ Intersection(r, FiniteSet(sin(x), cos(x))) assert Intersection(FiniteSet(x**2, 1, sin(x)), FiniteSet(x**2, 2, sin(x)), r) == \ Intersection(r, FiniteSet(x**2, sin(x))) def test_issue_11827(): assert S.Naturals0**4 def test_issue_10113(): f = x**2/(x**2 - 4) assert imageset(x, f, S.Reals) == Union(Interval(-oo, 0), Interval(1, oo, True, True)) assert imageset(x, f, Interval(-2, 2)) == Interval(-oo, 0) assert imageset(x, f, Interval(-2, 3)) == Union(Interval(-oo, 0), Interval(Rational(9, 5), oo)) def test_issue_10248(): raises( TypeError, lambda: list(Intersection(S.Reals, FiniteSet(x))) ) A = Symbol('A', real=True) assert list(Intersection(S.Reals, FiniteSet(A))) == [A] def test_issue_9447(): a = Interval(0, 1) + Interval(2, 3) assert Complement(S.UniversalSet, a) == Complement( S.UniversalSet, Union(Interval(0, 1), Interval(2, 3)), evaluate=False) assert Complement(S.Naturals, a) == Complement( S.Naturals, Union(Interval(0, 1), Interval(2, 3)), evaluate=False) def test_issue_10337(): assert (FiniteSet(2) == 3) is False assert (FiniteSet(2) != 3) is True raises(TypeError, lambda: FiniteSet(2) < 3) raises(TypeError, lambda: FiniteSet(2) <= 3) raises(TypeError, lambda: FiniteSet(2) > 3) raises(TypeError, lambda: FiniteSet(2) >= 3) def test_issue_10326(): bad = [ EmptySet, FiniteSet(1), Interval(1, 2), S.ComplexInfinity, S.ImaginaryUnit, S.Infinity, S.NaN, S.NegativeInfinity, ] interval = Interval(0, 5) for i in bad: assert i not in interval x = Symbol('x', real=True) nr = Symbol('nr', extended_real=False) assert x + 1 in Interval(x, x + 4) assert nr not in Interval(x, x + 4) assert Interval(1, 2) in FiniteSet(Interval(0, 5), Interval(1, 2)) assert Interval(-oo, oo).contains(oo) is S.false assert Interval(-oo, oo).contains(-oo) is S.false def test_issue_2799(): U = S.UniversalSet a = Symbol('a', real=True) inf_interval = Interval(a, oo) R = S.Reals assert U + inf_interval == inf_interval + U assert U + R == R + U assert R + inf_interval == inf_interval + R def test_issue_9706(): assert Interval(-oo, 0).closure == Interval(-oo, 0, True, False) assert Interval(0, oo).closure == Interval(0, oo, False, True) assert Interval(-oo, oo).closure == Interval(-oo, oo) def test_issue_8257(): reals_plus_infinity = Union(Interval(-oo, oo), FiniteSet(oo)) reals_plus_negativeinfinity = Union(Interval(-oo, oo), FiniteSet(-oo)) assert Interval(-oo, oo) + FiniteSet(oo) == reals_plus_infinity assert FiniteSet(oo) + Interval(-oo, oo) == reals_plus_infinity assert Interval(-oo, oo) + FiniteSet(-oo) == reals_plus_negativeinfinity assert FiniteSet(-oo) + Interval(-oo, oo) == reals_plus_negativeinfinity def test_issue_10931(): assert S.Integers - S.Integers == EmptySet assert S.Integers - S.Reals == EmptySet def test_issue_11174(): soln = Intersection(Interval(-oo, oo), FiniteSet(-x), evaluate=False) assert Intersection(FiniteSet(-x), S.Reals) == soln soln = Intersection(S.Reals, FiniteSet(x), evaluate=False) assert Intersection(FiniteSet(x), S.Reals) == soln def test_issue_18505(): assert ImageSet(Lambda(n, sqrt(pi*n/2 - 1 + pi/2)), S.Integers).contains(0) == \ Contains(0, ImageSet(Lambda(n, sqrt(pi*n/2 - 1 + pi/2)), S.Integers)) def test_finite_set_intersection(): # The following should not produce recursion errors # Note: some of these are not completely correct. See # https://github.com/sympy/sympy/issues/16342. assert Intersection(FiniteSet(-oo, x), FiniteSet(x)) == FiniteSet(x) assert Intersection._handle_finite_sets([FiniteSet(-oo, x), FiniteSet(0, x)]) == FiniteSet(x) assert Intersection._handle_finite_sets([FiniteSet(-oo, x), FiniteSet(x)]) == FiniteSet(x) assert Intersection._handle_finite_sets([FiniteSet(2, 3, x, y), FiniteSet(1, 2, x)]) == \ Intersection._handle_finite_sets([FiniteSet(1, 2, x), FiniteSet(2, 3, x, y)]) == \ Intersection(FiniteSet(1, 2, x), FiniteSet(2, 3, x, y)) == \ Intersection(FiniteSet(1, 2, x), FiniteSet(2, x, y)) assert FiniteSet(1+x-y) & FiniteSet(1) == \ FiniteSet(1) & FiniteSet(1+x-y) == \ Intersection(FiniteSet(1+x-y), FiniteSet(1), evaluate=False) assert FiniteSet(1) & FiniteSet(x) == FiniteSet(x) & FiniteSet(1) == \ Intersection(FiniteSet(1), FiniteSet(x), evaluate=False) assert FiniteSet({x}) & FiniteSet({x, y}) == \ Intersection(FiniteSet({x}), FiniteSet({x, y}), evaluate=False) def test_union_intersection_constructor(): # The actual exception does not matter here, so long as these fail sets = [FiniteSet(1), FiniteSet(2)] raises(Exception, lambda: Union(sets)) raises(Exception, lambda: Intersection(sets)) raises(Exception, lambda: Union(tuple(sets))) raises(Exception, lambda: Intersection(tuple(sets))) raises(Exception, lambda: Union(i for i in sets)) raises(Exception, lambda: Intersection(i for i in sets)) # Python sets are treated the same as FiniteSet # The union of a single set (of sets) is the set (of sets) itself assert Union(set(sets)) == FiniteSet(*sets) assert Intersection(set(sets)) == FiniteSet(*sets) assert Union({1}, {2}) == FiniteSet(1, 2) assert Intersection({1, 2}, {2, 3}) == FiniteSet(2) def test_Union_contains(): assert zoo not in Union( Interval.open(-oo, 0), Interval.open(0, oo)) @XFAIL def test_issue_16878b(): # in intersection_sets for (ImageSet, Set) there is no code # that handles the base_set of S.Reals like there is # for Integers assert imageset(x, (x, x), S.Reals).is_subset(S.Reals**2) is True def test_DisjointUnion(): assert DisjointUnion(FiniteSet(1, 2, 3), FiniteSet(1, 2, 3), FiniteSet(1, 2, 3)).rewrite(Union) == (FiniteSet(1, 2, 3) * FiniteSet(0, 1, 2)) assert DisjointUnion(Interval(1, 3), Interval(2, 4)).rewrite(Union) == Union(Interval(1, 3) * FiniteSet(0), Interval(2, 4) * FiniteSet(1)) assert DisjointUnion(Interval(0, 5), Interval(0, 5)).rewrite(Union) == Union(Interval(0, 5) * FiniteSet(0), Interval(0, 5) * FiniteSet(1)) assert DisjointUnion(Interval(-1, 2), S.EmptySet, S.EmptySet).rewrite(Union) == Interval(-1, 2) * FiniteSet(0) assert DisjointUnion(Interval(-1, 2)).rewrite(Union) == Interval(-1, 2) * FiniteSet(0) assert DisjointUnion(S.EmptySet, Interval(-1, 2), S.EmptySet).rewrite(Union) == Interval(-1, 2) * FiniteSet(1) assert DisjointUnion(Interval(-oo, oo)).rewrite(Union) == Interval(-oo, oo) * FiniteSet(0) assert DisjointUnion(S.EmptySet).rewrite(Union) == S.EmptySet assert DisjointUnion().rewrite(Union) == S.EmptySet raises(TypeError, lambda: DisjointUnion(Symbol('n'))) x = Symbol("x") y = Symbol("y") z = Symbol("z") assert DisjointUnion(FiniteSet(x), FiniteSet(y, z)).rewrite(Union) == (FiniteSet(x) * FiniteSet(0)) + (FiniteSet(y, z) * FiniteSet(1)) def test_DisjointUnion_is_empty(): assert DisjointUnion(S.EmptySet).is_empty is True assert DisjointUnion(S.EmptySet, S.EmptySet).is_empty is True assert DisjointUnion(S.EmptySet, FiniteSet(1, 2, 3)).is_empty is False def test_DisjointUnion_is_iterable(): assert DisjointUnion(S.Integers, S.Naturals, S.Rationals).is_iterable is True assert DisjointUnion(S.EmptySet, S.Reals).is_iterable is False assert DisjointUnion(FiniteSet(1, 2, 3), S.EmptySet, FiniteSet(x, y)).is_iterable is True assert DisjointUnion(S.EmptySet, S.EmptySet).is_iterable is False def test_DisjointUnion_contains(): assert (0, 0) in DisjointUnion(FiniteSet(0, 1, 2), FiniteSet(0, 1, 2), FiniteSet(0, 1, 2)) assert (0, 1) in DisjointUnion(FiniteSet(0, 1, 2), FiniteSet(0, 1, 2), FiniteSet(0, 1, 2)) assert (0, 2) in DisjointUnion(FiniteSet(0, 1, 2), FiniteSet(0, 1, 2), FiniteSet(0, 1, 2)) assert (1, 0) in DisjointUnion(FiniteSet(0, 1, 2), FiniteSet(0, 1, 2), FiniteSet(0, 1, 2)) assert (1, 1) in DisjointUnion(FiniteSet(0, 1, 2), FiniteSet(0, 1, 2), FiniteSet(0, 1, 2)) assert (1, 2) in DisjointUnion(FiniteSet(0, 1, 2), FiniteSet(0, 1, 2), FiniteSet(0, 1, 2)) assert (2, 0) in DisjointUnion(FiniteSet(0, 1, 2), FiniteSet(0, 1, 2), FiniteSet(0, 1, 2)) assert (2, 1) in DisjointUnion(FiniteSet(0, 1, 2), FiniteSet(0, 1, 2), FiniteSet(0, 1, 2)) assert (2, 2) in DisjointUnion(FiniteSet(0, 1, 2), FiniteSet(0, 1, 2), FiniteSet(0, 1, 2)) assert (0, 1, 2) not in DisjointUnion(FiniteSet(0, 1, 2), FiniteSet(0, 1, 2), FiniteSet(0, 1, 2)) assert (0, 0.5) not in DisjointUnion(FiniteSet(0.5)) assert (0, 5) not in DisjointUnion(FiniteSet(0, 1, 2), FiniteSet(0, 1, 2), FiniteSet(0, 1, 2)) assert (x, 0) in DisjointUnion(FiniteSet(x, y, z), S.EmptySet, FiniteSet(y)) assert (y, 0) in DisjointUnion(FiniteSet(x, y, z), S.EmptySet, FiniteSet(y)) assert (z, 0) in DisjointUnion(FiniteSet(x, y, z), S.EmptySet, FiniteSet(y)) assert (y, 2) in DisjointUnion(FiniteSet(x, y, z), S.EmptySet, FiniteSet(y)) assert (0.5, 0) in DisjointUnion(Interval(0, 1), Interval(0, 2)) assert (0.5, 1) in DisjointUnion(Interval(0, 1), Interval(0, 2)) assert (1.5, 0) not in DisjointUnion(Interval(0, 1), Interval(0, 2)) assert (1.5, 1) in DisjointUnion(Interval(0, 1), Interval(0, 2)) def test_DisjointUnion_iter(): D = DisjointUnion(FiniteSet(3, 5, 7, 9), FiniteSet(x, y, z)) it = iter(D) L1 = [(x, 1), (y, 1), (z, 1)] L2 = [(3, 0), (5, 0), (7, 0), (9, 0)] nxt = next(it) assert nxt in L2 L2.remove(nxt) nxt = next(it) assert nxt in L1 L1.remove(nxt) nxt = next(it) assert nxt in L2 L2.remove(nxt) nxt = next(it) assert nxt in L1 L1.remove(nxt) nxt = next(it) assert nxt in L2 L2.remove(nxt) nxt = next(it) assert nxt in L1 L1.remove(nxt) nxt = next(it) assert nxt in L2 L2.remove(nxt) raises(StopIteration, lambda: next(it)) raises(ValueError, lambda: iter(DisjointUnion(Interval(0, 1), S.EmptySet))) def test_DisjointUnion_len(): assert len(DisjointUnion(FiniteSet(3, 5, 7, 9), FiniteSet(x, y, z))) == 7 assert len(DisjointUnion(S.EmptySet, S.EmptySet, FiniteSet(x, y, z), S.EmptySet)) == 3 raises(ValueError, lambda: len(DisjointUnion(Interval(0, 1), S.EmptySet))) def test_issue_20089(): B = FiniteSet(FiniteSet(1, 2), FiniteSet(1)) assert not 1 in B assert not 1.0 in B assert not Eq(1, FiniteSet(1, 2)) assert FiniteSet(1) in B A = FiniteSet(1, 2) assert A in B assert B.issubset(B) assert not A.issubset(B) assert 1 in A C = FiniteSet(FiniteSet(1, 2), FiniteSet(1), 1, 2) assert A.issubset(C) assert B.issubset(C) def test_issue_19378(): a = FiniteSet(1, 2) b = ProductSet(a, a) c = FiniteSet((1, 1), (1, 2), (2, 1), (2, 2)) assert b.is_subset(c) is True d = FiniteSet(1) assert b.is_subset(d) is False assert Eq(c, b).simplify() is S.true assert Eq(a, c).simplify() is S.false assert Eq({1}, {x}).simplify() == Eq({1}, {x}) def test_issue_20379(): #https://github.com/sympy/sympy/issues/20379 x = pi - 3.14159265358979 assert FiniteSet(x).evalf(2) == FiniteSet(Float('3.23108914886517e-15', 2)) def test_finiteset_simplify(): S = FiniteSet(1, cos(1)**2 + sin(1)**2) assert S.simplify() == {1}
c7fe7235ff8f370ef7e7b594456dd4e046dbab196c73c8ebc0ec8392b6b818c4
""" Continuous Random Variables - Prebuilt variables Contains ======== Arcsin Benini Beta BetaNoncentral BetaPrime BoundedPareto Cauchy Chi ChiNoncentral ChiSquared Dagum Erlang ExGaussian Exponential ExponentialPower FDistribution FisherZ Frechet Gamma GammaInverse Gumbel Gompertz Kumaraswamy Laplace Levy LogCauchy Logistic LogLogistic LogitNormal LogNormal Lomax Maxwell Moyal Nakagami Normal Pareto PowerFunction QuadraticU RaisedCosine Rayleigh Reciprocal ShiftedGompertz StudentT Trapezoidal Triangular Uniform UniformSum VonMises Wald Weibull WignerSemicircle """ from sympy import beta as beta_fn from sympy import cos, sin, tan, atan, exp, besseli, besselj, besselk from sympy import (log, sqrt, pi, S, Dummy, Interval, sympify, gamma, sign, Piecewise, And, Eq, binomial, factorial, Sum, floor, Abs, Lambda, Basic, lowergamma, erf, erfc, erfi, erfinv, I, asin, hyper, uppergamma, sinh, Ne, expint, Rational, integrate) from sympy.matrices import MatrixBase from sympy.stats.crv import SingleContinuousPSpace, SingleContinuousDistribution from sympy.stats.rv import _value_check, is_random oo = S.Infinity __all__ = ['ContinuousRV', 'Arcsin', 'Benini', 'Beta', 'BetaNoncentral', 'BetaPrime', 'BoundedPareto', 'Cauchy', 'Chi', 'ChiNoncentral', 'ChiSquared', 'Dagum', 'Erlang', 'ExGaussian', 'Exponential', 'ExponentialPower', 'FDistribution', 'FisherZ', 'Frechet', 'Gamma', 'GammaInverse', 'Gompertz', 'Gumbel', 'Kumaraswamy', 'Laplace', 'Levy', 'LogCauchy', 'Logistic', 'LogLogistic', 'LogitNormal', 'LogNormal', 'Lomax', 'Maxwell', 'Moyal', 'Nakagami', 'Normal', 'GaussianInverse', 'Pareto', 'PowerFunction', 'QuadraticU', 'RaisedCosine', 'Rayleigh', 'Reciprocal', 'StudentT', 'ShiftedGompertz', 'Trapezoidal', 'Triangular', 'Uniform', 'UniformSum', 'VonMises', 'Wald', 'Weibull', 'WignerSemicircle', ] @is_random.register(MatrixBase) def _(x): return any([is_random(i) for i in x]) def rv(symbol, cls, args, **kwargs): args = list(map(sympify, args)) dist = cls(*args) if kwargs.pop('check', True): dist.check(*args) pspace = SingleContinuousPSpace(symbol, dist) if any(is_random(arg) for arg in args): from sympy.stats.compound_rv import CompoundPSpace, CompoundDistribution pspace = CompoundPSpace(symbol, CompoundDistribution(dist)) return pspace.value class ContinuousDistributionHandmade(SingleContinuousDistribution): _argnames = ('pdf',) def __new__(cls, pdf, set=Interval(-oo, oo)): return Basic.__new__(cls, pdf, set) @property def set(self): return self.args[1] @staticmethod def check(pdf, set): x = Dummy('x') val = integrate(pdf(x), (x, set)) _value_check(Eq(val, 1) != S.false, "The pdf on the given set is incorrect.") def ContinuousRV(symbol, density, set=Interval(-oo, oo), **kwargs): """ Create a Continuous Random Variable given the following: Parameters ========== symbol : Symbol Represents name of the random variable. density : Expression containing symbol Represents probability density function. set : set/Interval Represents the region where the pdf is valid, by default is real line. check : bool If True, it will check whether the given density integrates to 1 over the given set. If False, it will not perform this check. Default is False. Returns ======= RandomSymbol Many common continuous random variable types are already implemented. This function should be necessary only very rarely. Examples ======== >>> from sympy import Symbol, sqrt, exp, pi >>> from sympy.stats import ContinuousRV, P, E >>> x = Symbol("x") >>> pdf = sqrt(2)*exp(-x**2/2)/(2*sqrt(pi)) # Normal distribution >>> X = ContinuousRV(x, pdf) >>> E(X) 0 >>> P(X>0) 1/2 """ pdf = Piecewise((density, set.as_relational(symbol)), (0, True)) pdf = Lambda(symbol, pdf) # have a default of False while `rv` should have a default of True kwargs['check'] = kwargs.pop('check', False) return rv(symbol.name, ContinuousDistributionHandmade, (pdf, set), **kwargs) ######################################## # Continuous Probability Distributions # ######################################## #------------------------------------------------------------------------------- # Arcsin distribution ---------------------------------------------------------- class ArcsinDistribution(SingleContinuousDistribution): _argnames = ('a', 'b') @property def set(self): return Interval(self.a, self.b) def pdf(self, x): a, b = self.a, self.b return 1/(pi*sqrt((x - a)*(b - x))) def _cdf(self, x): a, b = self.a, self.b return Piecewise( (S.Zero, x < a), (2*asin(sqrt((x - a)/(b - a)))/pi, x <= b), (S.One, True)) def Arcsin(name, a=0, b=1): r""" Create a Continuous Random Variable with an arcsin distribution. The density of the arcsin distribution is given by .. math:: f(x) := \frac{1}{\pi\sqrt{(x-a)(b-x)}} with :math:`x \in (a,b)`. It must hold that :math:`-\infty < a < b < \infty`. Parameters ========== a : Real number, the left interval boundary b : Real number, the right interval boundary Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import Arcsin, density, cdf >>> from sympy import Symbol >>> a = Symbol("a", real=True) >>> b = Symbol("b", real=True) >>> z = Symbol("z") >>> X = Arcsin("x", a, b) >>> density(X)(z) 1/(pi*sqrt((-a + z)*(b - z))) >>> cdf(X)(z) Piecewise((0, a > z), (2*asin(sqrt((-a + z)/(-a + b)))/pi, b >= z), (1, True)) References ========== .. [1] https://en.wikipedia.org/wiki/Arcsine_distribution """ return rv(name, ArcsinDistribution, (a, b)) #------------------------------------------------------------------------------- # Benini distribution ---------------------------------------------------------- class BeniniDistribution(SingleContinuousDistribution): _argnames = ('alpha', 'beta', 'sigma') @staticmethod def check(alpha, beta, sigma): _value_check(alpha > 0, "Shape parameter Alpha must be positive.") _value_check(beta > 0, "Shape parameter Beta must be positive.") _value_check(sigma > 0, "Scale parameter Sigma must be positive.") @property def set(self): return Interval(self.sigma, oo) def pdf(self, x): alpha, beta, sigma = self.alpha, self.beta, self.sigma return (exp(-alpha*log(x/sigma) - beta*log(x/sigma)**2) *(alpha/x + 2*beta*log(x/sigma)/x)) def _moment_generating_function(self, t): raise NotImplementedError('The moment generating function of the ' 'Benini distribution does not exist.') def Benini(name, alpha, beta, sigma): r""" Create a Continuous Random Variable with a Benini distribution. The density of the Benini distribution is given by .. math:: f(x) := e^{-\alpha\log{\frac{x}{\sigma}} -\beta\log^2\left[{\frac{x}{\sigma}}\right]} \left(\frac{\alpha}{x}+\frac{2\beta\log{\frac{x}{\sigma}}}{x}\right) This is a heavy-tailed distribution and is also known as the log-Rayleigh distribution. Parameters ========== alpha : Real number, `\alpha > 0`, a shape beta : Real number, `\beta > 0`, a shape sigma : Real number, `\sigma > 0`, a scale Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import Benini, density, cdf >>> from sympy import Symbol, pprint >>> alpha = Symbol("alpha", positive=True) >>> beta = Symbol("beta", positive=True) >>> sigma = Symbol("sigma", positive=True) >>> z = Symbol("z") >>> X = Benini("x", alpha, beta, sigma) >>> D = density(X)(z) >>> pprint(D, use_unicode=False) / / z \\ / z \ 2/ z \ | 2*beta*log|-----|| - alpha*log|-----| - beta*log |-----| |alpha \sigma/| \sigma/ \sigma/ |----- + -----------------|*e \ z z / >>> cdf(X)(z) Piecewise((1 - exp(-alpha*log(z/sigma) - beta*log(z/sigma)**2), sigma <= z), (0, True)) References ========== .. [1] https://en.wikipedia.org/wiki/Benini_distribution .. [2] http://reference.wolfram.com/legacy/v8/ref/BeniniDistribution.html """ return rv(name, BeniniDistribution, (alpha, beta, sigma)) #------------------------------------------------------------------------------- # Beta distribution ------------------------------------------------------------ class BetaDistribution(SingleContinuousDistribution): _argnames = ('alpha', 'beta') set = Interval(0, 1) @staticmethod def check(alpha, beta): _value_check(alpha > 0, "Shape parameter Alpha must be positive.") _value_check(beta > 0, "Shape parameter Beta must be positive.") def pdf(self, x): alpha, beta = self.alpha, self.beta return x**(alpha - 1) * (1 - x)**(beta - 1) / beta_fn(alpha, beta) def _characteristic_function(self, t): return hyper((self.alpha,), (self.alpha + self.beta,), I*t) def _moment_generating_function(self, t): return hyper((self.alpha,), (self.alpha + self.beta,), t) def Beta(name, alpha, beta): r""" Create a Continuous Random Variable with a Beta distribution. The density of the Beta distribution is given by .. math:: f(x) := \frac{x^{\alpha-1}(1-x)^{\beta-1}} {\mathrm{B}(\alpha,\beta)} with :math:`x \in [0,1]`. Parameters ========== alpha : Real number, `\alpha > 0`, a shape beta : Real number, `\beta > 0`, a shape Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import Beta, density, E, variance >>> from sympy import Symbol, simplify, pprint, factor >>> alpha = Symbol("alpha", positive=True) >>> beta = Symbol("beta", positive=True) >>> z = Symbol("z") >>> X = Beta("x", alpha, beta) >>> D = density(X)(z) >>> pprint(D, use_unicode=False) alpha - 1 beta - 1 z *(1 - z) -------------------------- B(alpha, beta) >>> simplify(E(X)) alpha/(alpha + beta) >>> factor(simplify(variance(X))) alpha*beta/((alpha + beta)**2*(alpha + beta + 1)) References ========== .. [1] https://en.wikipedia.org/wiki/Beta_distribution .. [2] http://mathworld.wolfram.com/BetaDistribution.html """ return rv(name, BetaDistribution, (alpha, beta)) #------------------------------------------------------------------------------- # Noncentral Beta distribution ------------------------------------------------------------ class BetaNoncentralDistribution(SingleContinuousDistribution): _argnames = ('alpha', 'beta', 'lamda') set = Interval(0, 1) @staticmethod def check(alpha, beta, lamda): _value_check(alpha > 0, "Shape parameter Alpha must be positive.") _value_check(beta > 0, "Shape parameter Beta must be positive.") _value_check(lamda >= 0, "Noncentrality parameter Lambda must be positive") def pdf(self, x): alpha, beta, lamda = self.alpha, self.beta, self.lamda k = Dummy("k") return Sum(exp(-lamda / 2) * (lamda / 2)**k * x**(alpha + k - 1) *( 1 - x)**(beta - 1) / (factorial(k) * beta_fn(alpha + k, beta)), (k, 0, oo)) def BetaNoncentral(name, alpha, beta, lamda): r""" Create a Continuous Random Variable with a Type I Noncentral Beta distribution. The density of the Noncentral Beta distribution is given by .. math:: f(x) := \sum_{k=0}^\infty e^{-\lambda/2}\frac{(\lambda/2)^k}{k!} \frac{x^{\alpha+k-1}(1-x)^{\beta-1}}{\mathrm{B}(\alpha+k,\beta)} with :math:`x \in [0,1]`. Parameters ========== alpha : Real number, `\alpha > 0`, a shape beta : Real number, `\beta > 0`, a shape lamda: Real number, `\lambda >= 0`, noncentrality parameter Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import BetaNoncentral, density, cdf >>> from sympy import Symbol, pprint >>> alpha = Symbol("alpha", positive=True) >>> beta = Symbol("beta", positive=True) >>> lamda = Symbol("lamda", nonnegative=True) >>> z = Symbol("z") >>> X = BetaNoncentral("x", alpha, beta, lamda) >>> D = density(X)(z) >>> pprint(D, use_unicode=False) oo _____ \ ` \ -lamda \ k ------- \ k + alpha - 1 /lamda\ beta - 1 2 ) z *|-----| *(1 - z) *e / \ 2 / / ------------------------------------------------ / B(k + alpha, beta)*k! /____, k = 0 Compute cdf with specific 'x', 'alpha', 'beta' and 'lamda' values as follows : >>> cdf(BetaNoncentral("x", 1, 1, 1), evaluate=False)(2).doit() 2*exp(1/2) The argument evaluate=False prevents an attempt at evaluation of the sum for general x, before the argument 2 is passed. References ========== .. [1] https://en.wikipedia.org/wiki/Noncentral_beta_distribution .. [2] https://reference.wolfram.com/language/ref/NoncentralBetaDistribution.html """ return rv(name, BetaNoncentralDistribution, (alpha, beta, lamda)) #------------------------------------------------------------------------------- # Beta prime distribution ------------------------------------------------------ class BetaPrimeDistribution(SingleContinuousDistribution): _argnames = ('alpha', 'beta') @staticmethod def check(alpha, beta): _value_check(alpha > 0, "Shape parameter Alpha must be positive.") _value_check(beta > 0, "Shape parameter Beta must be positive.") set = Interval(0, oo) def pdf(self, x): alpha, beta = self.alpha, self.beta return x**(alpha - 1)*(1 + x)**(-alpha - beta)/beta_fn(alpha, beta) def BetaPrime(name, alpha, beta): r""" Create a continuous random variable with a Beta prime distribution. The density of the Beta prime distribution is given by .. math:: f(x) := \frac{x^{\alpha-1} (1+x)^{-\alpha -\beta}}{B(\alpha,\beta)} with :math:`x > 0`. Parameters ========== alpha : Real number, `\alpha > 0`, a shape beta : Real number, `\beta > 0`, a shape Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import BetaPrime, density >>> from sympy import Symbol, pprint >>> alpha = Symbol("alpha", positive=True) >>> beta = Symbol("beta", positive=True) >>> z = Symbol("z") >>> X = BetaPrime("x", alpha, beta) >>> D = density(X)(z) >>> pprint(D, use_unicode=False) alpha - 1 -alpha - beta z *(z + 1) ------------------------------- B(alpha, beta) References ========== .. [1] https://en.wikipedia.org/wiki/Beta_prime_distribution .. [2] http://mathworld.wolfram.com/BetaPrimeDistribution.html """ return rv(name, BetaPrimeDistribution, (alpha, beta)) #------------------------------------------------------------------------------- # Bounded Pareto Distribution -------------------------------------------------- class BoundedParetoDistribution(SingleContinuousDistribution): _argnames = ('alpha', 'left', 'right') @property def set(self): return Interval(self.left , self.right) @staticmethod def check(alpha, left, right): _value_check (alpha.is_positive, "Shape must be positive.") _value_check (left.is_positive, "Left value should be positive.") _value_check (right > left, "Right should be greater than left.") def pdf(self, x): alpha, left, right = self.alpha, self.left, self.right num = alpha * (left**alpha) * x**(- alpha -1) den = 1 - (left/right)**alpha return num/den def BoundedPareto(name, alpha, left, right): r""" Create a continuous random variable with a Bounded Pareto distribution. The density of the Bounded Pareto distribution is given by .. math:: f(x) := \frac{\alpha L^{\alpha}x^{-\alpha-1}}{1-(\frac{L}{H})^{\alpha}} Parameters ========== alpha : Real Number, `alpha > 0` Shape parameter left : Real Number, `left > 0` Location parameter right : Real Number, `right > left` Location parameter Examples ======== >>> from sympy.stats import BoundedPareto, density, cdf, E >>> from sympy import symbols >>> L, H = symbols('L, H', positive=True) >>> X = BoundedPareto('X', 2, L, H) >>> x = symbols('x') >>> density(X)(x) 2*L**2/(x**3*(1 - L**2/H**2)) >>> cdf(X)(x) Piecewise((-H**2*L**2/(x**2*(H**2 - L**2)) + H**2/(H**2 - L**2), L <= x), (0, True)) >>> E(X).simplify() 2*H*L/(H + L) Returns ======= RandomSymbol References ========== .. [1] https://en.wikipedia.org/wiki/Pareto_distribution#Bounded_Pareto_distribution """ return rv (name, BoundedParetoDistribution, (alpha, left, right)) # ------------------------------------------------------------------------------ # Cauchy distribution ---------------------------------------------------------- class CauchyDistribution(SingleContinuousDistribution): _argnames = ('x0', 'gamma') @staticmethod def check(x0, gamma): _value_check(gamma > 0, "Scale parameter Gamma must be positive.") _value_check(x0.is_real, "Location parameter must be real.") def pdf(self, x): return 1/(pi*self.gamma*(1 + ((x - self.x0)/self.gamma)**2)) def _cdf(self, x): x0, gamma = self.x0, self.gamma return (1/pi)*atan((x - x0)/gamma) + S.Half def _characteristic_function(self, t): return exp(self.x0 * I * t - self.gamma * Abs(t)) def _moment_generating_function(self, t): raise NotImplementedError("The moment generating function for the " "Cauchy distribution does not exist.") def _quantile(self, p): return self.x0 + self.gamma*tan(pi*(p - S.Half)) def Cauchy(name, x0, gamma): r""" Create a continuous random variable with a Cauchy distribution. The density of the Cauchy distribution is given by .. math:: f(x) := \frac{1}{\pi \gamma [1 + {(\frac{x-x_0}{\gamma})}^2]} Parameters ========== x0 : Real number, the location gamma : Real number, `\gamma > 0`, a scale Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import Cauchy, density >>> from sympy import Symbol >>> x0 = Symbol("x0") >>> gamma = Symbol("gamma", positive=True) >>> z = Symbol("z") >>> X = Cauchy("x", x0, gamma) >>> density(X)(z) 1/(pi*gamma*(1 + (-x0 + z)**2/gamma**2)) References ========== .. [1] https://en.wikipedia.org/wiki/Cauchy_distribution .. [2] http://mathworld.wolfram.com/CauchyDistribution.html """ return rv(name, CauchyDistribution, (x0, gamma)) #------------------------------------------------------------------------------- # Chi distribution ------------------------------------------------------------- class ChiDistribution(SingleContinuousDistribution): _argnames = ('k',) @staticmethod def check(k): _value_check(k > 0, "Number of degrees of freedom (k) must be positive.") _value_check(k.is_integer, "Number of degrees of freedom (k) must be an integer.") set = Interval(0, oo) def pdf(self, x): return 2**(1 - self.k/2)*x**(self.k - 1)*exp(-x**2/2)/gamma(self.k/2) def _characteristic_function(self, t): k = self.k part_1 = hyper((k/2,), (S.Half,), -t**2/2) part_2 = I*t*sqrt(2)*gamma((k+1)/2)/gamma(k/2) part_3 = hyper(((k+1)/2,), (Rational(3, 2),), -t**2/2) return part_1 + part_2*part_3 def _moment_generating_function(self, t): k = self.k part_1 = hyper((k / 2,), (S.Half,), t ** 2 / 2) part_2 = t * sqrt(2) * gamma((k + 1) / 2) / gamma(k / 2) part_3 = hyper(((k + 1) / 2,), (S(3) / 2,), t ** 2 / 2) return part_1 + part_2 * part_3 def Chi(name, k): r""" Create a continuous random variable with a Chi distribution. The density of the Chi distribution is given by .. math:: f(x) := \frac{2^{1-k/2}x^{k-1}e^{-x^2/2}}{\Gamma(k/2)} with :math:`x \geq 0`. Parameters ========== k : Positive integer, The number of degrees of freedom Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import Chi, density, E >>> from sympy import Symbol, simplify >>> k = Symbol("k", integer=True) >>> z = Symbol("z") >>> X = Chi("x", k) >>> density(X)(z) 2**(1 - k/2)*z**(k - 1)*exp(-z**2/2)/gamma(k/2) >>> simplify(E(X)) sqrt(2)*gamma(k/2 + 1/2)/gamma(k/2) References ========== .. [1] https://en.wikipedia.org/wiki/Chi_distribution .. [2] http://mathworld.wolfram.com/ChiDistribution.html """ return rv(name, ChiDistribution, (k,)) #------------------------------------------------------------------------------- # Non-central Chi distribution ------------------------------------------------- class ChiNoncentralDistribution(SingleContinuousDistribution): _argnames = ('k', 'l') @staticmethod def check(k, l): _value_check(k > 0, "Number of degrees of freedom (k) must be positive.") _value_check(k.is_integer, "Number of degrees of freedom (k) must be an integer.") _value_check(l > 0, "Shift parameter Lambda must be positive.") set = Interval(0, oo) def pdf(self, x): k, l = self.k, self.l return exp(-(x**2+l**2)/2)*x**k*l / (l*x)**(k/2) * besseli(k/2-1, l*x) def ChiNoncentral(name, k, l): r""" Create a continuous random variable with a non-central Chi distribution. Explanation =========== The density of the non-central Chi distribution is given by .. math:: f(x) := \frac{e^{-(x^2+\lambda^2)/2} x^k\lambda} {(\lambda x)^{k/2}} I_{k/2-1}(\lambda x) with `x \geq 0`. Here, `I_\nu (x)` is the :ref:`modified Bessel function of the first kind <besseli>`. Parameters ========== k : A positive Integer, $k > 0$ The number of degrees of freedom. lambda : Real number, `\lambda > 0` Shift parameter. Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import ChiNoncentral, density >>> from sympy import Symbol >>> k = Symbol("k", integer=True) >>> l = Symbol("l") >>> z = Symbol("z") >>> X = ChiNoncentral("x", k, l) >>> density(X)(z) l*z**k*exp(-l**2/2 - z**2/2)*besseli(k/2 - 1, l*z)/(l*z)**(k/2) References ========== .. [1] https://en.wikipedia.org/wiki/Noncentral_chi_distribution """ return rv(name, ChiNoncentralDistribution, (k, l)) #------------------------------------------------------------------------------- # Chi squared distribution ----------------------------------------------------- class ChiSquaredDistribution(SingleContinuousDistribution): _argnames = ('k',) @staticmethod def check(k): _value_check(k > 0, "Number of degrees of freedom (k) must be positive.") _value_check(k.is_integer, "Number of degrees of freedom (k) must be an integer.") set = Interval(0, oo) def pdf(self, x): k = self.k return 1/(2**(k/2)*gamma(k/2))*x**(k/2 - 1)*exp(-x/2) def _cdf(self, x): k = self.k return Piecewise( (S.One/gamma(k/2)*lowergamma(k/2, x/2), x >= 0), (0, True) ) def _characteristic_function(self, t): return (1 - 2*I*t)**(-self.k/2) def _moment_generating_function(self, t): return (1 - 2*t)**(-self.k/2) def ChiSquared(name, k): r""" Create a continuous random variable with a Chi-squared distribution. Explanation =========== The density of the Chi-squared distribution is given by .. math:: f(x) := \frac{1}{2^{\frac{k}{2}}\Gamma\left(\frac{k}{2}\right)} x^{\frac{k}{2}-1} e^{-\frac{x}{2}} with :math:`x \geq 0`. Parameters ========== k : Positive integer The number of degrees of freedom. Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import ChiSquared, density, E, variance, moment >>> from sympy import Symbol >>> k = Symbol("k", integer=True, positive=True) >>> z = Symbol("z") >>> X = ChiSquared("x", k) >>> density(X)(z) z**(k/2 - 1)*exp(-z/2)/(2**(k/2)*gamma(k/2)) >>> E(X) k >>> variance(X) 2*k >>> moment(X, 3) k**3 + 6*k**2 + 8*k References ========== .. [1] https://en.wikipedia.org/wiki/Chi_squared_distribution .. [2] http://mathworld.wolfram.com/Chi-SquaredDistribution.html """ return rv(name, ChiSquaredDistribution, (k, )) #------------------------------------------------------------------------------- # Dagum distribution ----------------------------------------------------------- class DagumDistribution(SingleContinuousDistribution): _argnames = ('p', 'a', 'b') set = Interval(0, oo) @staticmethod def check(p, a, b): _value_check(p > 0, "Shape parameter p must be positive.") _value_check(a > 0, "Shape parameter a must be positive.") _value_check(b > 0, "Scale parameter b must be positive.") def pdf(self, x): p, a, b = self.p, self.a, self.b return a*p/x*((x/b)**(a*p)/(((x/b)**a + 1)**(p + 1))) def _cdf(self, x): p, a, b = self.p, self.a, self.b return Piecewise(((S.One + (S(x)/b)**-a)**-p, x>=0), (S.Zero, True)) def Dagum(name, p, a, b): r""" Create a continuous random variable with a Dagum distribution. Explanation =========== The density of the Dagum distribution is given by .. math:: f(x) := \frac{a p}{x} \left( \frac{\left(\tfrac{x}{b}\right)^{a p}} {\left(\left(\tfrac{x}{b}\right)^a + 1 \right)^{p+1}} \right) with :math:`x > 0`. Parameters ========== p : Real number ``p > 0``, a shape. a : Real number ``a > 0``, a shape. b : Real number ``b > 0``, a scale. Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import Dagum, density, cdf >>> from sympy import Symbol >>> p = Symbol("p", positive=True) >>> a = Symbol("a", positive=True) >>> b = Symbol("b", positive=True) >>> z = Symbol("z") >>> X = Dagum("x", p, a, b) >>> density(X)(z) a*p*(z/b)**(a*p)*((z/b)**a + 1)**(-p - 1)/z >>> cdf(X)(z) Piecewise(((1 + (z/b)**(-a))**(-p), z >= 0), (0, True)) References ========== .. [1] https://en.wikipedia.org/wiki/Dagum_distribution """ return rv(name, DagumDistribution, (p, a, b)) #------------------------------------------------------------------------------- # Erlang distribution ---------------------------------------------------------- def Erlang(name, k, l): r""" Create a continuous random variable with an Erlang distribution. Explanation =========== The density of the Erlang distribution is given by .. math:: f(x) := \frac{\lambda^k x^{k-1} e^{-\lambda x}}{(k-1)!} with :math:`x \in [0,\infty]`. Parameters ========== k : Positive integer l : Real number, `\lambda > 0`, the rate Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import Erlang, density, cdf, E, variance >>> from sympy import Symbol, simplify, pprint >>> k = Symbol("k", integer=True, positive=True) >>> l = Symbol("l", positive=True) >>> z = Symbol("z") >>> X = Erlang("x", k, l) >>> D = density(X)(z) >>> pprint(D, use_unicode=False) k k - 1 -l*z l *z *e --------------- Gamma(k) >>> C = cdf(X)(z) >>> pprint(C, use_unicode=False) /lowergamma(k, l*z) |------------------ for z > 0 < Gamma(k) | \ 0 otherwise >>> E(X) k/l >>> simplify(variance(X)) k/l**2 References ========== .. [1] https://en.wikipedia.org/wiki/Erlang_distribution .. [2] http://mathworld.wolfram.com/ErlangDistribution.html """ return rv(name, GammaDistribution, (k, S.One/l)) # ------------------------------------------------------------------------------- # ExGaussian distribution ----------------------------------------------------- class ExGaussianDistribution(SingleContinuousDistribution): _argnames = ('mean', 'std', 'rate') set = Interval(-oo, oo) @staticmethod def check(mean, std, rate): _value_check( std > 0, "Standard deviation of ExGaussian must be positive.") _value_check(rate > 0, "Rate of ExGaussian must be positive.") def pdf(self, x): mean, std, rate = self.mean, self.std, self.rate term1 = rate/2 term2 = exp(rate * (2 * mean + rate * std**2 - 2*x)/2) term3 = erfc((mean + rate*std**2 - x)/(sqrt(2)*std)) return term1*term2*term3 def _cdf(self, x): from sympy.stats import cdf mean, std, rate = self.mean, self.std, self.rate u = rate*(x - mean) v = rate*std GaussianCDF1 = cdf(Normal('x', 0, v))(u) GaussianCDF2 = cdf(Normal('x', v**2, v))(u) return GaussianCDF1 - exp(-u + (v**2/2) + log(GaussianCDF2)) def _characteristic_function(self, t): mean, std, rate = self.mean, self.std, self.rate term1 = (1 - I*t/rate)**(-1) term2 = exp(I*mean*t - std**2*t**2/2) return term1 * term2 def _moment_generating_function(self, t): mean, std, rate = self.mean, self.std, self.rate term1 = (1 - t/rate)**(-1) term2 = exp(mean*t + std**2*t**2/2) return term1*term2 def ExGaussian(name, mean, std, rate): r""" Create a continuous random variable with an Exponentially modified Gaussian (EMG) distribution. Explanation =========== The density of the exponentially modified Gaussian distribution is given by .. math:: f(x) := \frac{\lambda}{2}e^{\frac{\lambda}{2}(2\mu+\lambda\sigma^2-2x)} \text{erfc}(\frac{\mu + \lambda\sigma^2 - x}{\sqrt{2}\sigma}) with $x > 0$. Note that the expected value is `1/\lambda`. Parameters ========== mu : A Real number, the mean of Gaussian component std: A positive Real number, :math: `\sigma^2 > 0` the variance of Gaussian component lambda: A positive Real number, :math: `\lambda > 0` the rate of Exponential component Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import ExGaussian, density, cdf, E >>> from sympy.stats import variance, skewness >>> from sympy import Symbol, pprint, simplify >>> mean = Symbol("mu") >>> std = Symbol("sigma", positive=True) >>> rate = Symbol("lamda", positive=True) >>> z = Symbol("z") >>> X = ExGaussian("x", mean, std, rate) >>> pprint(density(X)(z), use_unicode=False) / 2 \ lamda*\lamda*sigma + 2*mu - 2*z/ --------------------------------- / ___ / 2 \\ 2 |\/ 2 *\lamda*sigma + mu - z/| lamda*e *erfc|-----------------------------| \ 2*sigma / ---------------------------------------------------------------------------- 2 >>> cdf(X)(z) -(erf(sqrt(2)*(-lamda**2*sigma**2 + lamda*(-mu + z))/(2*lamda*sigma))/2 + 1/2)*exp(lamda**2*sigma**2/2 - lamda*(-mu + z)) + erf(sqrt(2)*(-mu + z)/(2*sigma))/2 + 1/2 >>> E(X) (lamda*mu + 1)/lamda >>> simplify(variance(X)) sigma**2 + lamda**(-2) >>> simplify(skewness(X)) 2/(lamda**2*sigma**2 + 1)**(3/2) References ========== .. [1] https://en.wikipedia.org/wiki/Exponentially_modified_Gaussian_distribution """ return rv(name, ExGaussianDistribution, (mean, std, rate)) #------------------------------------------------------------------------------- # Exponential distribution ----------------------------------------------------- class ExponentialDistribution(SingleContinuousDistribution): _argnames = ('rate',) set = Interval(0, oo) @staticmethod def check(rate): _value_check(rate > 0, "Rate must be positive.") def pdf(self, x): return self.rate * exp(-self.rate*x) def _cdf(self, x): return Piecewise( (S.One - exp(-self.rate*x), x >= 0), (0, True), ) def _characteristic_function(self, t): rate = self.rate return rate / (rate - I*t) def _moment_generating_function(self, t): rate = self.rate return rate / (rate - t) def _quantile(self, p): return -log(1-p)/self.rate def Exponential(name, rate): r""" Create a continuous random variable with an Exponential distribution. Explanation =========== The density of the exponential distribution is given by .. math:: f(x) := \lambda \exp(-\lambda x) with $x > 0$. Note that the expected value is `1/\lambda`. Parameters ========== rate : A positive Real number, `\lambda > 0`, the rate (or inverse scale/inverse mean) Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import Exponential, density, cdf, E >>> from sympy.stats import variance, std, skewness, quantile >>> from sympy import Symbol >>> l = Symbol("lambda", positive=True) >>> z = Symbol("z") >>> p = Symbol("p") >>> X = Exponential("x", l) >>> density(X)(z) lambda*exp(-lambda*z) >>> cdf(X)(z) Piecewise((1 - exp(-lambda*z), z >= 0), (0, True)) >>> quantile(X)(p) -log(1 - p)/lambda >>> E(X) 1/lambda >>> variance(X) lambda**(-2) >>> skewness(X) 2 >>> X = Exponential('x', 10) >>> density(X)(z) 10*exp(-10*z) >>> E(X) 1/10 >>> std(X) 1/10 References ========== .. [1] https://en.wikipedia.org/wiki/Exponential_distribution .. [2] http://mathworld.wolfram.com/ExponentialDistribution.html """ return rv(name, ExponentialDistribution, (rate, )) # ------------------------------------------------------------------------------- # Exponential Power distribution ----------------------------------------------------- class ExponentialPowerDistribution(SingleContinuousDistribution): _argnames = ('mu', 'alpha', 'beta') set = Interval(-oo, oo) @staticmethod def check(mu, alpha, beta): _value_check(alpha > 0, "Scale parameter alpha must be positive.") _value_check(beta > 0, "Shape parameter beta must be positive.") def pdf(self, x): mu, alpha, beta = self.mu, self.alpha, self.beta num = beta*exp(-(Abs(x - mu)/alpha)**beta) den = 2*alpha*gamma(1/beta) return num/den def _cdf(self, x): mu, alpha, beta = self.mu, self.alpha, self.beta num = lowergamma(1/beta, (Abs(x - mu) / alpha)**beta) den = 2*gamma(1/beta) return sign(x - mu)*num/den + S.Half def ExponentialPower(name, mu, alpha, beta): r""" Create a Continuous Random Variable with Exponential Power distribution. This distribution is known also as Generalized Normal distribution version 1. Explanation =========== The density of the Exponential Power distribution is given by .. math:: f(x) := \frac{\beta}{2\alpha\Gamma(\frac{1}{\beta})} e^{{-(\frac{|x - \mu|}{\alpha})^{\beta}}} with :math:`x \in [ - \infty, \infty ]`. Parameters ========== mu : Real number A location. alpha : Real number,``alpha > 0`` A scale. beta : Real number, ``beta > 0`` A shape. Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import ExponentialPower, density, cdf >>> from sympy import Symbol, pprint >>> z = Symbol("z") >>> mu = Symbol("mu") >>> alpha = Symbol("alpha", positive=True) >>> beta = Symbol("beta", positive=True) >>> X = ExponentialPower("x", mu, alpha, beta) >>> pprint(density(X)(z), use_unicode=False) beta /|mu - z|\ -|--------| \ alpha / beta*e --------------------- / 1 \ 2*alpha*Gamma|----| \beta/ >>> cdf(X)(z) 1/2 + lowergamma(1/beta, (Abs(mu - z)/alpha)**beta)*sign(-mu + z)/(2*gamma(1/beta)) References ========== .. [1] https://reference.wolfram.com/language/ref/ExponentialPowerDistribution.html .. [2] https://en.wikipedia.org/wiki/Generalized_normal_distribution#Version_1 """ return rv(name, ExponentialPowerDistribution, (mu, alpha, beta)) #------------------------------------------------------------------------------- # F distribution --------------------------------------------------------------- class FDistributionDistribution(SingleContinuousDistribution): _argnames = ('d1', 'd2') set = Interval(0, oo) @staticmethod def check(d1, d2): _value_check((d1 > 0, d1.is_integer), "Degrees of freedom d1 must be positive integer.") _value_check((d2 > 0, d2.is_integer), "Degrees of freedom d2 must be positive integer.") def pdf(self, x): d1, d2 = self.d1, self.d2 return (sqrt((d1*x)**d1*d2**d2 / (d1*x+d2)**(d1+d2)) / (x * beta_fn(d1/2, d2/2))) def _moment_generating_function(self, t): raise NotImplementedError('The moment generating function for the ' 'F-distribution does not exist.') def FDistribution(name, d1, d2): r""" Create a continuous random variable with a F distribution. Explanation =========== The density of the F distribution is given by .. math:: f(x) := \frac{\sqrt{\frac{(d_1 x)^{d_1} d_2^{d_2}} {(d_1 x + d_2)^{d_1 + d_2}}}} {x \mathrm{B} \left(\frac{d_1}{2}, \frac{d_2}{2}\right)} with :math:`x > 0`. Parameters ========== d1 : `d_1 > 0`, where d_1 is the degrees of freedom (n_1 - 1) d2 : `d_2 > 0`, where d_2 is the degrees of freedom (n_2 - 1) Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import FDistribution, density >>> from sympy import Symbol, pprint >>> d1 = Symbol("d1", positive=True) >>> d2 = Symbol("d2", positive=True) >>> z = Symbol("z") >>> X = FDistribution("x", d1, d2) >>> D = density(X)(z) >>> pprint(D, use_unicode=False) d2 -- ______________________________ 2 / d1 -d1 - d2 d2 *\/ (d1*z) *(d1*z + d2) -------------------------------------- /d1 d2\ z*B|--, --| \2 2 / References ========== .. [1] https://en.wikipedia.org/wiki/F-distribution .. [2] http://mathworld.wolfram.com/F-Distribution.html """ return rv(name, FDistributionDistribution, (d1, d2)) #------------------------------------------------------------------------------- # Fisher Z distribution -------------------------------------------------------- class FisherZDistribution(SingleContinuousDistribution): _argnames = ('d1', 'd2') set = Interval(-oo, oo) @staticmethod def check(d1, d2): _value_check(d1 > 0, "Degree of freedom d1 must be positive.") _value_check(d2 > 0, "Degree of freedom d2 must be positive.") def pdf(self, x): d1, d2 = self.d1, self.d2 return (2*d1**(d1/2)*d2**(d2/2) / beta_fn(d1/2, d2/2) * exp(d1*x) / (d1*exp(2*x)+d2)**((d1+d2)/2)) def FisherZ(name, d1, d2): r""" Create a Continuous Random Variable with an Fisher's Z distribution. Explanation =========== The density of the Fisher's Z distribution is given by .. math:: f(x) := \frac{2d_1^{d_1/2} d_2^{d_2/2}} {\mathrm{B}(d_1/2, d_2/2)} \frac{e^{d_1z}}{\left(d_1e^{2z}+d_2\right)^{\left(d_1+d_2\right)/2}} .. TODO - What is the difference between these degrees of freedom? Parameters ========== d1 : ``d_1 > 0`` Degree of freedom. d2 : ``d_2 > 0`` Degree of freedom. Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import FisherZ, density >>> from sympy import Symbol, pprint >>> d1 = Symbol("d1", positive=True) >>> d2 = Symbol("d2", positive=True) >>> z = Symbol("z") >>> X = FisherZ("x", d1, d2) >>> D = density(X)(z) >>> pprint(D, use_unicode=False) d1 d2 d1 d2 - -- - -- -- -- 2 2 2 2 / 2*z \ d1*z 2*d1 *d2 *\d1*e + d2/ *e ----------------------------------------- /d1 d2\ B|--, --| \2 2 / References ========== .. [1] https://en.wikipedia.org/wiki/Fisher%27s_z-distribution .. [2] http://mathworld.wolfram.com/Fishersz-Distribution.html """ return rv(name, FisherZDistribution, (d1, d2)) #------------------------------------------------------------------------------- # Frechet distribution --------------------------------------------------------- class FrechetDistribution(SingleContinuousDistribution): _argnames = ('a', 's', 'm') set = Interval(0, oo) @staticmethod def check(a, s, m): _value_check(a > 0, "Shape parameter alpha must be positive.") _value_check(s > 0, "Scale parameter s must be positive.") def __new__(cls, a, s=1, m=0): a, s, m = list(map(sympify, (a, s, m))) return Basic.__new__(cls, a, s, m) def pdf(self, x): a, s, m = self.a, self.s, self.m return a/s * ((x-m)/s)**(-1-a) * exp(-((x-m)/s)**(-a)) def _cdf(self, x): a, s, m = self.a, self.s, self.m return Piecewise((exp(-((x-m)/s)**(-a)), x >= m), (S.Zero, True)) def Frechet(name, a, s=1, m=0): r""" Create a continuous random variable with a Frechet distribution. Explanation =========== The density of the Frechet distribution is given by .. math:: f(x) := \frac{\alpha}{s} \left(\frac{x-m}{s}\right)^{-1-\alpha} e^{-(\frac{x-m}{s})^{-\alpha}} with :math:`x \geq m`. Parameters ========== a : Real number, :math:`a \in \left(0, \infty\right)` the shape s : Real number, :math:`s \in \left(0, \infty\right)` the scale m : Real number, :math:`m \in \left(-\infty, \infty\right)` the minimum Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import Frechet, density, cdf >>> from sympy import Symbol >>> a = Symbol("a", positive=True) >>> s = Symbol("s", positive=True) >>> m = Symbol("m", real=True) >>> z = Symbol("z") >>> X = Frechet("x", a, s, m) >>> density(X)(z) a*((-m + z)/s)**(-a - 1)*exp(-1/((-m + z)/s)**a)/s >>> cdf(X)(z) Piecewise((exp(-1/((-m + z)/s)**a), m <= z), (0, True)) References ========== .. [1] https://en.wikipedia.org/wiki/Fr%C3%A9chet_distribution """ return rv(name, FrechetDistribution, (a, s, m)) #------------------------------------------------------------------------------- # Gamma distribution ----------------------------------------------------------- class GammaDistribution(SingleContinuousDistribution): _argnames = ('k', 'theta') set = Interval(0, oo) @staticmethod def check(k, theta): _value_check(k > 0, "k must be positive") _value_check(theta > 0, "Theta must be positive") def pdf(self, x): k, theta = self.k, self.theta return x**(k - 1) * exp(-x/theta) / (gamma(k)*theta**k) def _cdf(self, x): k, theta = self.k, self.theta return Piecewise( (lowergamma(k, S(x)/theta)/gamma(k), x > 0), (S.Zero, True)) def _characteristic_function(self, t): return (1 - self.theta*I*t)**(-self.k) def _moment_generating_function(self, t): return (1- self.theta*t)**(-self.k) def Gamma(name, k, theta): r""" Create a continuous random variable with a Gamma distribution. Explanation =========== The density of the Gamma distribution is given by .. math:: f(x) := \frac{1}{\Gamma(k) \theta^k} x^{k - 1} e^{-\frac{x}{\theta}} with :math:`x \in [0,1]`. Parameters ========== k : Real number, ``k > 0``, a shape theta : Real number, `\theta > 0`, a scale Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import Gamma, density, cdf, E, variance >>> from sympy import Symbol, pprint, simplify >>> k = Symbol("k", positive=True) >>> theta = Symbol("theta", positive=True) >>> z = Symbol("z") >>> X = Gamma("x", k, theta) >>> D = density(X)(z) >>> pprint(D, use_unicode=False) -z ----- -k k - 1 theta theta *z *e --------------------- Gamma(k) >>> C = cdf(X, meijerg=True)(z) >>> pprint(C, use_unicode=False) / / z \ |k*lowergamma|k, -----| | \ theta/ <---------------------- for z >= 0 | Gamma(k + 1) | \ 0 otherwise >>> E(X) k*theta >>> V = simplify(variance(X)) >>> pprint(V, use_unicode=False) 2 k*theta References ========== .. [1] https://en.wikipedia.org/wiki/Gamma_distribution .. [2] http://mathworld.wolfram.com/GammaDistribution.html """ return rv(name, GammaDistribution, (k, theta)) #------------------------------------------------------------------------------- # Inverse Gamma distribution --------------------------------------------------- class GammaInverseDistribution(SingleContinuousDistribution): _argnames = ('a', 'b') set = Interval(0, oo) @staticmethod def check(a, b): _value_check(a > 0, "alpha must be positive") _value_check(b > 0, "beta must be positive") def pdf(self, x): a, b = self.a, self.b return b**a/gamma(a) * x**(-a-1) * exp(-b/x) def _cdf(self, x): a, b = self.a, self.b return Piecewise((uppergamma(a,b/x)/gamma(a), x > 0), (S.Zero, True)) def _characteristic_function(self, t): a, b = self.a, self.b return 2 * (-I*b*t)**(a/2) * besselk(a, sqrt(-4*I*b*t)) / gamma(a) def _moment_generating_function(self, t): raise NotImplementedError('The moment generating function for the ' 'gamma inverse distribution does not exist.') def GammaInverse(name, a, b): r""" Create a continuous random variable with an inverse Gamma distribution. Explanation =========== The density of the inverse Gamma distribution is given by .. math:: f(x) := \frac{\beta^\alpha}{\Gamma(\alpha)} x^{-\alpha - 1} \exp\left(\frac{-\beta}{x}\right) with :math:`x > 0`. Parameters ========== a : Real number, `a > 0` a shape b : Real number, `b > 0` a scale Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import GammaInverse, density, cdf >>> from sympy import Symbol, pprint >>> a = Symbol("a", positive=True) >>> b = Symbol("b", positive=True) >>> z = Symbol("z") >>> X = GammaInverse("x", a, b) >>> D = density(X)(z) >>> pprint(D, use_unicode=False) -b --- a -a - 1 z b *z *e --------------- Gamma(a) >>> cdf(X)(z) Piecewise((uppergamma(a, b/z)/gamma(a), z > 0), (0, True)) References ========== .. [1] https://en.wikipedia.org/wiki/Inverse-gamma_distribution """ return rv(name, GammaInverseDistribution, (a, b)) #------------------------------------------------------------------------------- # Gumbel distribution (Maximum and Minimum) -------------------------------------------------------- class GumbelDistribution(SingleContinuousDistribution): _argnames = ('beta', 'mu', 'minimum') set = Interval(-oo, oo) @staticmethod def check(beta, mu, minimum): _value_check(beta > 0, "Scale parameter beta must be positive.") def pdf(self, x): beta, mu = self.beta, self.mu z = (x - mu)/beta f_max = (1/beta)*exp(-z - exp(-z)) f_min = (1/beta)*exp(z - exp(z)) return Piecewise((f_min, self.minimum), (f_max, not self.minimum)) def _cdf(self, x): beta, mu = self.beta, self.mu z = (x - mu)/beta F_max = exp(-exp(-z)) F_min = 1 - exp(-exp(z)) return Piecewise((F_min, self.minimum), (F_max, not self.minimum)) def _characteristic_function(self, t): cf_max = gamma(1 - I*self.beta*t) * exp(I*self.mu*t) cf_min = gamma(1 + I*self.beta*t) * exp(I*self.mu*t) return Piecewise((cf_min, self.minimum), (cf_max, not self.minimum)) def _moment_generating_function(self, t): mgf_max = gamma(1 - self.beta*t) * exp(self.mu*t) mgf_min = gamma(1 + self.beta*t) * exp(self.mu*t) return Piecewise((mgf_min, self.minimum), (mgf_max, not self.minimum)) def Gumbel(name, beta, mu, minimum=False): r""" Create a Continuous Random Variable with Gumbel distribution. Explanation =========== The density of the Gumbel distribution is given by For Maximum .. math:: f(x) := \dfrac{1}{\beta} \exp \left( -\dfrac{x-\mu}{\beta} - \exp \left( -\dfrac{x - \mu}{\beta} \right) \right) with :math:`x \in [ - \infty, \infty ]`. For Minimum .. math:: f(x) := \frac{e^{- e^{\frac{- \mu + x}{\beta}} + \frac{- \mu + x}{\beta}}}{\beta} with :math:`x \in [ - \infty, \infty ]`. Parameters ========== mu : Real number, 'mu' is a location beta : Real number, 'beta > 0' is a scale minimum : Boolean, by default, False, set to True for enabling minimum distribution Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import Gumbel, density, cdf >>> from sympy import Symbol >>> x = Symbol("x") >>> mu = Symbol("mu") >>> beta = Symbol("beta", positive=True) >>> X = Gumbel("x", beta, mu) >>> density(X)(x) exp(-exp(-(-mu + x)/beta) - (-mu + x)/beta)/beta >>> cdf(X)(x) exp(-exp(-(-mu + x)/beta)) References ========== .. [1] http://mathworld.wolfram.com/GumbelDistribution.html .. [2] https://en.wikipedia.org/wiki/Gumbel_distribution .. [3] http://www.mathwave.com/help/easyfit/html/analyses/distributions/gumbel_max.html .. [4] http://www.mathwave.com/help/easyfit/html/analyses/distributions/gumbel_min.html """ return rv(name, GumbelDistribution, (beta, mu, minimum)) #------------------------------------------------------------------------------- # Gompertz distribution -------------------------------------------------------- class GompertzDistribution(SingleContinuousDistribution): _argnames = ('b', 'eta') set = Interval(0, oo) @staticmethod def check(b, eta): _value_check(b > 0, "b must be positive") _value_check(eta > 0, "eta must be positive") def pdf(self, x): eta, b = self.eta, self.b return b*eta*exp(b*x)*exp(eta)*exp(-eta*exp(b*x)) def _cdf(self, x): eta, b = self.eta, self.b return 1 - exp(eta)*exp(-eta*exp(b*x)) def _moment_generating_function(self, t): eta, b = self.eta, self.b return eta * exp(eta) * expint(t/b, eta) def Gompertz(name, b, eta): r""" Create a Continuous Random Variable with Gompertz distribution. Explanation =========== The density of the Gompertz distribution is given by .. math:: f(x) := b \eta e^{b x} e^{\eta} \exp \left(-\eta e^{bx} \right) with :math: 'x \in [0, \inf)'. Parameters ========== b: Real number, 'b > 0' a scale eta: Real number, 'eta > 0' a shape Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import Gompertz, density >>> from sympy import Symbol >>> b = Symbol("b", positive=True) >>> eta = Symbol("eta", positive=True) >>> z = Symbol("z") >>> X = Gompertz("x", b, eta) >>> density(X)(z) b*eta*exp(eta)*exp(b*z)*exp(-eta*exp(b*z)) References ========== .. [1] https://en.wikipedia.org/wiki/Gompertz_distribution """ return rv(name, GompertzDistribution, (b, eta)) #------------------------------------------------------------------------------- # Kumaraswamy distribution ----------------------------------------------------- class KumaraswamyDistribution(SingleContinuousDistribution): _argnames = ('a', 'b') set = Interval(0, oo) @staticmethod def check(a, b): _value_check(a > 0, "a must be positive") _value_check(b > 0, "b must be positive") def pdf(self, x): a, b = self.a, self.b return a * b * x**(a-1) * (1-x**a)**(b-1) def _cdf(self, x): a, b = self.a, self.b return Piecewise( (S.Zero, x < S.Zero), (1 - (1 - x**a)**b, x <= S.One), (S.One, True)) def Kumaraswamy(name, a, b): r""" Create a Continuous Random Variable with a Kumaraswamy distribution. Explanation =========== The density of the Kumaraswamy distribution is given by .. math:: f(x) := a b x^{a-1} (1-x^a)^{b-1} with :math:`x \in [0,1]`. Parameters ========== a : Real number, ``a > 0`` a shape b : Real number, ``b > 0`` a shape Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import Kumaraswamy, density, cdf >>> from sympy import Symbol, pprint >>> a = Symbol("a", positive=True) >>> b = Symbol("b", positive=True) >>> z = Symbol("z") >>> X = Kumaraswamy("x", a, b) >>> D = density(X)(z) >>> pprint(D, use_unicode=False) b - 1 a - 1 / a\ a*b*z *\1 - z / >>> cdf(X)(z) Piecewise((0, z < 0), (1 - (1 - z**a)**b, z <= 1), (1, True)) References ========== .. [1] https://en.wikipedia.org/wiki/Kumaraswamy_distribution """ return rv(name, KumaraswamyDistribution, (a, b)) #------------------------------------------------------------------------------- # Laplace distribution --------------------------------------------------------- class LaplaceDistribution(SingleContinuousDistribution): _argnames = ('mu', 'b') set = Interval(-oo, oo) @staticmethod def check(mu, b): _value_check(b > 0, "Scale parameter b must be positive.") _value_check(mu.is_real, "Location parameter mu should be real") def pdf(self, x): mu, b = self.mu, self.b return 1/(2*b)*exp(-Abs(x - mu)/b) def _cdf(self, x): mu, b = self.mu, self.b return Piecewise( (S.Half*exp((x - mu)/b), x < mu), (S.One - S.Half*exp(-(x - mu)/b), x >= mu) ) def _characteristic_function(self, t): return exp(self.mu*I*t) / (1 + self.b**2*t**2) def _moment_generating_function(self, t): return exp(self.mu*t) / (1 - self.b**2*t**2) def Laplace(name, mu, b): r""" Create a continuous random variable with a Laplace distribution. Explanation =========== The density of the Laplace distribution is given by .. math:: f(x) := \frac{1}{2 b} \exp \left(-\frac{|x-\mu|}b \right) Parameters ========== mu : Real number or a list/matrix, the location (mean) or the location vector b : Real number or a positive definite matrix, representing a scale or the covariance matrix. Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import Laplace, density, cdf >>> from sympy import Symbol, pprint >>> mu = Symbol("mu") >>> b = Symbol("b", positive=True) >>> z = Symbol("z") >>> X = Laplace("x", mu, b) >>> density(X)(z) exp(-Abs(mu - z)/b)/(2*b) >>> cdf(X)(z) Piecewise((exp((-mu + z)/b)/2, mu > z), (1 - exp((mu - z)/b)/2, True)) >>> L = Laplace('L', [1, 2], [[1, 0], [0, 1]]) >>> pprint(density(L)(1, 2), use_unicode=False) 5 / ____\ e *besselk\0, \/ 35 / --------------------- pi References ========== .. [1] https://en.wikipedia.org/wiki/Laplace_distribution .. [2] http://mathworld.wolfram.com/LaplaceDistribution.html """ if isinstance(mu, (list, MatrixBase)) and\ isinstance(b, (list, MatrixBase)): from sympy.stats.joint_rv_types import MultivariateLaplace return MultivariateLaplace(name, mu, b) return rv(name, LaplaceDistribution, (mu, b)) #------------------------------------------------------------------------------- # Levy distribution --------------------------------------------------------- class LevyDistribution(SingleContinuousDistribution): _argnames = ('mu', 'c') @property def set(self): return Interval(self.mu, oo) @staticmethod def check(mu, c): _value_check(c > 0, "c (scale parameter) must be positive") _value_check(mu.is_real, "mu (location paramater) must be real") def pdf(self, x): mu, c = self.mu, self.c return sqrt(c/(2*pi))*exp(-c/(2*(x - mu)))/((x - mu)**(S.One + S.Half)) def _cdf(self, x): mu, c = self.mu, self.c return erfc(sqrt(c/(2*(x - mu)))) def _characteristic_function(self, t): mu, c = self.mu, self.c return exp(I * mu * t - sqrt(-2 * I * c * t)) def _moment_generating_function(self, t): raise NotImplementedError('The moment generating function of Levy distribution does not exist.') def Levy(name, mu, c): r""" Create a continuous random variable with a Levy distribution. The density of the Levy distribution is given by .. math:: f(x) := \sqrt(\frac{c}{2 \pi}) \frac{\exp -\frac{c}{2 (x - \mu)}}{(x - \mu)^{3/2}} Parameters ========== mu : Real number The location parameter. c : Real number, ``c > 0`` A scale parameter. Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import Levy, density, cdf >>> from sympy import Symbol >>> mu = Symbol("mu", real=True) >>> c = Symbol("c", positive=True) >>> z = Symbol("z") >>> X = Levy("x", mu, c) >>> density(X)(z) sqrt(2)*sqrt(c)*exp(-c/(-2*mu + 2*z))/(2*sqrt(pi)*(-mu + z)**(3/2)) >>> cdf(X)(z) erfc(sqrt(c)*sqrt(1/(-2*mu + 2*z))) References ========== .. [1] https://en.wikipedia.org/wiki/L%C3%A9vy_distribution .. [2] http://mathworld.wolfram.com/LevyDistribution.html """ return rv(name, LevyDistribution, (mu, c)) #------------------------------------------------------------------------------- # Log-Cauchy distribution -------------------------------------------------------- class LogCauchyDistribution(SingleContinuousDistribution): _argnames = ('mu', 'sigma') set = Interval.open(0, oo) @staticmethod def check(mu, sigma): _value_check((sigma > 0) != False, "Scale parameter Gamma must be positive.") _value_check(mu.is_real != False, "Location parameter must be real.") def pdf(self, x): mu, sigma = self.mu, self.sigma return 1/(x*pi)*(sigma/((log(x) - mu)**2 + sigma**2)) def _cdf(self, x): mu, sigma = self.mu, self.sigma return (1/pi)*atan((log(x) - mu)/sigma) + S.Half def _characteristic_function(self, t): raise NotImplementedError("The characteristic function for the " "Log-Cauchy distribution does not exist.") def _moment_generating_function(self, t): raise NotImplementedError("The moment generating function for the " "Log-Cauchy distribution does not exist.") def LogCauchy(name, mu, sigma): r""" Create a continuous random variable with a Log-Cauchy distribution. The density of the Log-Cauchy distribution is given by .. math:: f(x) := \frac{1}{\pi x} \frac{\sigma}{(log(x)-\mu^2) + \sigma^2} Parameters ========== mu : Real number, the location sigma : Real number, `\sigma > 0`, a scale Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import LogCauchy, density, cdf >>> from sympy import Symbol, S >>> mu = 2 >>> sigma = S.One / 5 >>> z = Symbol("z") >>> X = LogCauchy("x", mu, sigma) >>> density(X)(z) 1/(5*pi*z*((log(z) - 2)**2 + 1/25)) >>> cdf(X)(z) atan(5*log(z) - 10)/pi + 1/2 References ========== .. [1] https://en.wikipedia.org/wiki/Log-Cauchy_distribution """ return rv(name, LogCauchyDistribution, (mu, sigma)) #------------------------------------------------------------------------------- # Logistic distribution -------------------------------------------------------- class LogisticDistribution(SingleContinuousDistribution): _argnames = ('mu', 's') set = Interval(-oo, oo) @staticmethod def check(mu, s): _value_check(s > 0, "Scale parameter s must be positive.") def pdf(self, x): mu, s = self.mu, self.s return exp(-(x - mu)/s)/(s*(1 + exp(-(x - mu)/s))**2) def _cdf(self, x): mu, s = self.mu, self.s return S.One/(1 + exp(-(x - mu)/s)) def _characteristic_function(self, t): return Piecewise((exp(I*t*self.mu) * pi*self.s*t / sinh(pi*self.s*t), Ne(t, 0)), (S.One, True)) def _moment_generating_function(self, t): return exp(self.mu*t) * beta_fn(1 - self.s*t, 1 + self.s*t) def _quantile(self, p): return self.mu - self.s*log(-S.One + S.One/p) def Logistic(name, mu, s): r""" Create a continuous random variable with a logistic distribution. Explanation =========== The density of the logistic distribution is given by .. math:: f(x) := \frac{e^{-(x-\mu)/s}} {s\left(1+e^{-(x-\mu)/s}\right)^2} Parameters ========== mu : Real number, the location (mean) s : Real number, `s > 0` a scale Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import Logistic, density, cdf >>> from sympy import Symbol >>> mu = Symbol("mu", real=True) >>> s = Symbol("s", positive=True) >>> z = Symbol("z") >>> X = Logistic("x", mu, s) >>> density(X)(z) exp((mu - z)/s)/(s*(exp((mu - z)/s) + 1)**2) >>> cdf(X)(z) 1/(exp((mu - z)/s) + 1) References ========== .. [1] https://en.wikipedia.org/wiki/Logistic_distribution .. [2] http://mathworld.wolfram.com/LogisticDistribution.html """ return rv(name, LogisticDistribution, (mu, s)) #------------------------------------------------------------------------------- # Log-logistic distribution -------------------------------------------------------- class LogLogisticDistribution(SingleContinuousDistribution): _argnames = ('alpha', 'beta') set = Interval(0, oo) @staticmethod def check(alpha, beta): _value_check(alpha > 0, "Scale parameter Alpha must be positive.") _value_check(beta > 0, "Shape parameter Beta must be positive.") def pdf(self, x): a, b = self.alpha, self.beta return ((b/a)*(x/a)**(b - 1))/(1 + (x/a)**b)**2 def _cdf(self, x): a, b = self.alpha, self.beta return 1/(1 + (x/a)**(-b)) def _quantile(self, p): a, b = self.alpha, self.beta return a*((p/(1 - p))**(1/b)) def expectation(self, expr, var, **kwargs): a, b = self.args return Piecewise((S.NaN, b <= 1), (pi*a/(b*sin(pi/b)), True)) def LogLogistic(name, alpha, beta): r""" Create a continuous random variable with a log-logistic distribution. The distribution is unimodal when ``beta > 1``. Explanation =========== The density of the log-logistic distribution is given by .. math:: f(x) := \frac{(\frac{\beta}{\alpha})(\frac{x}{\alpha})^{\beta - 1}} {(1 + (\frac{x}{\alpha})^{\beta})^2} Parameters ========== alpha : Real number, `\alpha > 0`, scale parameter and median of distribution beta : Real number, `\beta > 0` a shape parameter Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import LogLogistic, density, cdf, quantile >>> from sympy import Symbol, pprint >>> alpha = Symbol("alpha", real=True, positive=True) >>> beta = Symbol("beta", real=True, positive=True) >>> p = Symbol("p") >>> z = Symbol("z", positive=True) >>> X = LogLogistic("x", alpha, beta) >>> D = density(X)(z) >>> pprint(D, use_unicode=False) beta - 1 / z \ beta*|-----| \alpha/ ------------------------ 2 / beta \ |/ z \ | alpha*||-----| + 1| \\alpha/ / >>> cdf(X)(z) 1/(1 + (z/alpha)**(-beta)) >>> quantile(X)(p) alpha*(p/(1 - p))**(1/beta) References ========== .. [1] https://en.wikipedia.org/wiki/Log-logistic_distribution """ return rv(name, LogLogisticDistribution, (alpha, beta)) #------------------------------------------------------------------------------- #Logit-Normal distribution------------------------------------------------------ class LogitNormalDistribution(SingleContinuousDistribution): _argnames = ('mu', 's') set = Interval.open(0, 1) @staticmethod def check(mu, s): _value_check((s ** 2).is_real is not False and s ** 2 > 0, "Squared scale parameter s must be positive.") _value_check(mu.is_real is not False, "Location parameter must be real") def _logit(self, x): return log(x / (1 - x)) def pdf(self, x): mu, s = self.mu, self.s return exp(-(self._logit(x) - mu)**2/(2*s**2))*(S.One/sqrt(2*pi*(s**2)))*(1/(x*(1 - x))) def _cdf(self, x): mu, s = self.mu, self.s return (S.One/2)*(1 + erf((self._logit(x) - mu)/(sqrt(2*s**2)))) def LogitNormal(name, mu, s): r""" Create a continuous random variable with a Logit-Normal distribution. The density of the logistic distribution is given by .. math:: f(x) := \frac{1}{s \sqrt{2 \pi}} \frac{1}{x(1 - x)} e^{- \frac{(logit(x) - \mu)^2}{s^2}} where logit(x) = \log(\frac{x}{1 - x}) Parameters ========== mu : Real number, the location (mean) s : Real number, `s > 0` a scale Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import LogitNormal, density, cdf >>> from sympy import Symbol,pprint >>> mu = Symbol("mu", real=True) >>> s = Symbol("s", positive=True) >>> z = Symbol("z") >>> X = LogitNormal("x",mu,s) >>> D = density(X)(z) >>> pprint(D, use_unicode=False) 2 / / z \\ -|-mu + log|-----|| \ \1 - z// --------------------- 2 ___ 2*s \/ 2 *e ---------------------------- ____ 2*\/ pi *s*z*(1 - z) >>> density(X)(z) sqrt(2)*exp(-(-mu + log(z/(1 - z)))**2/(2*s**2))/(2*sqrt(pi)*s*z*(1 - z)) >>> cdf(X)(z) erf(sqrt(2)*(-mu + log(z/(1 - z)))/(2*s))/2 + 1/2 References ========== .. [1] https://en.wikipedia.org/wiki/Logit-normal_distribution """ return rv(name, LogitNormalDistribution, (mu, s)) #------------------------------------------------------------------------------- # Log Normal distribution ------------------------------------------------------ class LogNormalDistribution(SingleContinuousDistribution): _argnames = ('mean', 'std') set = Interval(0, oo) @staticmethod def check(mean, std): _value_check(std > 0, "Parameter std must be positive.") def pdf(self, x): mean, std = self.mean, self.std return exp(-(log(x) - mean)**2 / (2*std**2)) / (x*sqrt(2*pi)*std) def _cdf(self, x): mean, std = self.mean, self.std return Piecewise( (S.Half + S.Half*erf((log(x) - mean)/sqrt(2)/std), x > 0), (S.Zero, True) ) def _moment_generating_function(self, t): raise NotImplementedError('Moment generating function of the log-normal distribution is not defined.') def LogNormal(name, mean, std): r""" Create a continuous random variable with a log-normal distribution. Explanation =========== The density of the log-normal distribution is given by .. math:: f(x) := \frac{1}{x\sqrt{2\pi\sigma^2}} e^{-\frac{\left(\ln x-\mu\right)^2}{2\sigma^2}} with :math:`x \geq 0`. Parameters ========== mu : Real number The log-scale. sigma : Real number A shape. ($\sigma^2 > 0$) Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import LogNormal, density >>> from sympy import Symbol, pprint >>> mu = Symbol("mu", real=True) >>> sigma = Symbol("sigma", positive=True) >>> z = Symbol("z") >>> X = LogNormal("x", mu, sigma) >>> D = density(X)(z) >>> pprint(D, use_unicode=False) 2 -(-mu + log(z)) ----------------- 2 ___ 2*sigma \/ 2 *e ------------------------ ____ 2*\/ pi *sigma*z >>> X = LogNormal('x', 0, 1) # Mean 0, standard deviation 1 >>> density(X)(z) sqrt(2)*exp(-log(z)**2/2)/(2*sqrt(pi)*z) References ========== .. [1] https://en.wikipedia.org/wiki/Lognormal .. [2] http://mathworld.wolfram.com/LogNormalDistribution.html """ return rv(name, LogNormalDistribution, (mean, std)) #------------------------------------------------------------------------------- # Lomax Distribution ----------------------------------------------------------- class LomaxDistribution(SingleContinuousDistribution): _argnames = ('alpha', 'lamda',) set = Interval(0, oo) @staticmethod def check(alpha, lamda): _value_check(alpha.is_real, "Shape parameter should be real.") _value_check(lamda.is_real, "Scale parameter should be real.") _value_check(alpha.is_positive, "Shape parameter should be positive.") _value_check(lamda.is_positive, "Scale parameter should be positive.") def pdf(self, x): lamba, alpha = self.lamda, self.alpha return (alpha/lamba) * (S.One + x/lamba)**(-alpha-1) def Lomax(name, alpha, lamda): r""" Create a continuous random variable with a Lomax distribution. Explanation =========== The density of the Lomax distribution is given by .. math:: f(x) := \frac{\alpha}{\lambda}\left[1+\frac{x}{\lambda}\right]^{-(\alpha+1)} Parameters ========== alpha : Real Number, `alpha > 0` Shape parameter lamda : Real Number, `lamda > 0` Scale parameter Examples ======== >>> from sympy.stats import Lomax, density, cdf, E >>> from sympy import symbols >>> a, l = symbols('a, l', positive=True) >>> X = Lomax('X', a, l) >>> x = symbols('x') >>> density(X)(x) a*(1 + x/l)**(-a - 1)/l >>> cdf(X)(x) Piecewise((1 - 1/(1 + x/l)**a, x >= 0), (0, True)) >>> a = 2 >>> X = Lomax('X', a, l) >>> E(X) l Returns ======= RandomSymbol References ========== .. [1] https://en.wikipedia.org/wiki/Lomax_distribution """ return rv(name, LomaxDistribution, (alpha, lamda)) #------------------------------------------------------------------------------- # Maxwell distribution --------------------------------------------------------- class MaxwellDistribution(SingleContinuousDistribution): _argnames = ('a',) set = Interval(0, oo) @staticmethod def check(a): _value_check(a > 0, "Parameter a must be positive.") def pdf(self, x): a = self.a return sqrt(2/pi)*x**2*exp(-x**2/(2*a**2))/a**3 def _cdf(self, x): a = self.a return erf(sqrt(2)*x/(2*a)) - sqrt(2)*x*exp(-x**2/(2*a**2))/(sqrt(pi)*a) def Maxwell(name, a): r""" Create a continuous random variable with a Maxwell distribution. Explanation =========== The density of the Maxwell distribution is given by .. math:: f(x) := \sqrt{\frac{2}{\pi}} \frac{x^2 e^{-x^2/(2a^2)}}{a^3} with :math:`x \geq 0`. .. TODO - what does the parameter mean? Parameters ========== a : Real number, `a > 0` Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import Maxwell, density, E, variance >>> from sympy import Symbol, simplify >>> a = Symbol("a", positive=True) >>> z = Symbol("z") >>> X = Maxwell("x", a) >>> density(X)(z) sqrt(2)*z**2*exp(-z**2/(2*a**2))/(sqrt(pi)*a**3) >>> E(X) 2*sqrt(2)*a/sqrt(pi) >>> simplify(variance(X)) a**2*(-8 + 3*pi)/pi References ========== .. [1] https://en.wikipedia.org/wiki/Maxwell_distribution .. [2] http://mathworld.wolfram.com/MaxwellDistribution.html """ return rv(name, MaxwellDistribution, (a, )) #------------------------------------------------------------------------------- # Moyal Distribution ----------------------------------------------------------- class MoyalDistribution(SingleContinuousDistribution): _argnames = ('mu', 'sigma') @staticmethod def check(mu, sigma): _value_check(mu.is_real, "Location parameter must be real.") _value_check(sigma.is_real and sigma > 0, "Scale parameter must be real\ and positive.") def pdf(self, x): mu, sigma = self.mu, self.sigma num = exp(-(exp(-(x - mu)/sigma) + (x - mu)/(sigma))/2) den = (sqrt(2*pi) * sigma) return num/den def _characteristic_function(self, t): mu, sigma = self.mu, self.sigma term1 = exp(I*t*mu) term2 = (2**(-I*sigma*t) * gamma(Rational(1, 2) - I*t*sigma)) return (term1 * term2)/sqrt(pi) def _moment_generating_function(self, t): mu, sigma = self.mu, self.sigma term1 = exp(t*mu) term2 = (2**(-1*sigma*t) * gamma(Rational(1, 2) - t*sigma)) return (term1 * term2)/sqrt(pi) def Moyal(name, mu, sigma): r""" Create a continuous random variable with a Moyal distribution. Explanation =========== The density of the Moyal distribution is given by .. math:: f(x) := \frac{\exp-\frac{1}{2}\exp-\frac{x-\mu}{\sigma}-\frac{x-\mu}{2\sigma}}{\sqrt{2\pi}\sigma} with :math:`x \in \mathbb{R}`. Parameters ========== mu : Real number Location parameter sigma : Real positive number Scale parameter Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import Moyal, density, cdf >>> from sympy import Symbol, simplify >>> mu = Symbol("mu", real=True) >>> sigma = Symbol("sigma", positive=True, real=True) >>> z = Symbol("z") >>> X = Moyal("x", mu, sigma) >>> density(X)(z) sqrt(2)*exp(-exp((mu - z)/sigma)/2 - (-mu + z)/(2*sigma))/(2*sqrt(pi)*sigma) >>> simplify(cdf(X)(z)) 1 - erf(sqrt(2)*exp((mu - z)/(2*sigma))/2) References ========== .. [1] https://reference.wolfram.com/language/ref/MoyalDistribution.html .. [2] http://www.stat.rice.edu/~dobelman/textfiles/DistributionsHandbook.pdf """ return rv(name, MoyalDistribution, (mu, sigma)) #------------------------------------------------------------------------------- # Nakagami distribution -------------------------------------------------------- class NakagamiDistribution(SingleContinuousDistribution): _argnames = ('mu', 'omega') set = Interval(0, oo) @staticmethod def check(mu, omega): _value_check(mu >= S.Half, "Shape parameter mu must be greater than equal to 1/2.") _value_check(omega > 0, "Spread parameter omega must be positive.") def pdf(self, x): mu, omega = self.mu, self.omega return 2*mu**mu/(gamma(mu)*omega**mu)*x**(2*mu - 1)*exp(-mu/omega*x**2) def _cdf(self, x): mu, omega = self.mu, self.omega return Piecewise( (lowergamma(mu, (mu/omega)*x**2)/gamma(mu), x > 0), (S.Zero, True)) def Nakagami(name, mu, omega): r""" Create a continuous random variable with a Nakagami distribution. Explanation =========== The density of the Nakagami distribution is given by .. math:: f(x) := \frac{2\mu^\mu}{\Gamma(\mu)\omega^\mu} x^{2\mu-1} \exp\left(-\frac{\mu}{\omega}x^2 \right) with :math:`x > 0`. Parameters ========== mu : Real number, `\mu \geq \frac{1}{2}` a shape omega : Real number, `\omega > 0`, the spread Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import Nakagami, density, E, variance, cdf >>> from sympy import Symbol, simplify, pprint >>> mu = Symbol("mu", positive=True) >>> omega = Symbol("omega", positive=True) >>> z = Symbol("z") >>> X = Nakagami("x", mu, omega) >>> D = density(X)(z) >>> pprint(D, use_unicode=False) 2 -mu*z ------- mu -mu 2*mu - 1 omega 2*mu *omega *z *e ---------------------------------- Gamma(mu) >>> simplify(E(X)) sqrt(mu)*sqrt(omega)*gamma(mu + 1/2)/gamma(mu + 1) >>> V = simplify(variance(X)) >>> pprint(V, use_unicode=False) 2 omega*Gamma (mu + 1/2) omega - ----------------------- Gamma(mu)*Gamma(mu + 1) >>> cdf(X)(z) Piecewise((lowergamma(mu, mu*z**2/omega)/gamma(mu), z > 0), (0, True)) References ========== .. [1] https://en.wikipedia.org/wiki/Nakagami_distribution """ return rv(name, NakagamiDistribution, (mu, omega)) #------------------------------------------------------------------------------- # Normal distribution ---------------------------------------------------------- class NormalDistribution(SingleContinuousDistribution): _argnames = ('mean', 'std') @staticmethod def check(mean, std): _value_check(std > 0, "Standard deviation must be positive") def pdf(self, x): return exp(-(x - self.mean)**2 / (2*self.std**2)) / (sqrt(2*pi)*self.std) def _cdf(self, x): mean, std = self.mean, self.std return erf(sqrt(2)*(-mean + x)/(2*std))/2 + S.Half def _characteristic_function(self, t): mean, std = self.mean, self.std return exp(I*mean*t - std**2*t**2/2) def _moment_generating_function(self, t): mean, std = self.mean, self.std return exp(mean*t + std**2*t**2/2) def _quantile(self, p): mean, std = self.mean, self.std return mean + std*sqrt(2)*erfinv(2*p - 1) def Normal(name, mean, std): r""" Create a continuous random variable with a Normal distribution. Explanation =========== The density of the Normal distribution is given by .. math:: f(x) := \frac{1}{\sigma\sqrt{2\pi}} e^{ -\frac{(x-\mu)^2}{2\sigma^2} } Parameters ========== mu : Real number or a list representing the mean or the mean vector sigma : Real number or a positive definite square matrix, :math:`\sigma^2 > 0` the variance Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import Normal, density, E, std, cdf, skewness, quantile, marginal_distribution >>> from sympy import Symbol, simplify, pprint >>> mu = Symbol("mu") >>> sigma = Symbol("sigma", positive=True) >>> z = Symbol("z") >>> y = Symbol("y") >>> p = Symbol("p") >>> X = Normal("x", mu, sigma) >>> density(X)(z) sqrt(2)*exp(-(-mu + z)**2/(2*sigma**2))/(2*sqrt(pi)*sigma) >>> C = simplify(cdf(X))(z) # it needs a little more help... >>> pprint(C, use_unicode=False) / ___ \ |\/ 2 *(-mu + z)| erf|---------------| \ 2*sigma / 1 -------------------- + - 2 2 >>> quantile(X)(p) mu + sqrt(2)*sigma*erfinv(2*p - 1) >>> simplify(skewness(X)) 0 >>> X = Normal("x", 0, 1) # Mean 0, standard deviation 1 >>> density(X)(z) sqrt(2)*exp(-z**2/2)/(2*sqrt(pi)) >>> E(2*X + 1) 1 >>> simplify(std(2*X + 1)) 2 >>> m = Normal('X', [1, 2], [[2, 1], [1, 2]]) >>> pprint(density(m)(y, z), use_unicode=False) 2 2 y y*z z - -- + --- - -- + z - 1 ___ 3 3 3 \/ 3 *e ------------------------------ 6*pi >>> marginal_distribution(m, m[0])(1) 1/(2*sqrt(pi)) References ========== .. [1] https://en.wikipedia.org/wiki/Normal_distribution .. [2] http://mathworld.wolfram.com/NormalDistributionFunction.html """ if isinstance(mean, list) or getattr(mean, 'is_Matrix', False) and\ isinstance(std, list) or getattr(std, 'is_Matrix', False): from sympy.stats.joint_rv_types import MultivariateNormal return MultivariateNormal(name, mean, std) return rv(name, NormalDistribution, (mean, std)) #------------------------------------------------------------------------------- # Inverse Gaussian distribution ---------------------------------------------------------- class GaussianInverseDistribution(SingleContinuousDistribution): _argnames = ('mean', 'shape') @property def set(self): return Interval(0, oo) @staticmethod def check(mean, shape): _value_check(shape > 0, "Shape parameter must be positive") _value_check(mean > 0, "Mean must be positive") def pdf(self, x): mu, s = self.mean, self.shape return exp(-s*(x - mu)**2 / (2*x*mu**2)) * sqrt(s/(2*pi*x**3)) def _cdf(self, x): from sympy.stats import cdf mu, s = self.mean, self.shape stdNormalcdf = cdf(Normal('x', 0, 1)) first_term = stdNormalcdf(sqrt(s/x) * ((x/mu) - S.One)) second_term = exp(2*s/mu) * stdNormalcdf(-sqrt(s/x)*(x/mu + S.One)) return first_term + second_term def _characteristic_function(self, t): mu, s = self.mean, self.shape return exp((s/mu)*(1 - sqrt(1 - (2*mu**2*I*t)/s))) def _moment_generating_function(self, t): mu, s = self.mean, self.shape return exp((s/mu)*(1 - sqrt(1 - (2*mu**2*t)/s))) def GaussianInverse(name, mean, shape): r""" Create a continuous random variable with an Inverse Gaussian distribution. Inverse Gaussian distribution is also known as Wald distribution. Explanation =========== The density of the Inverse Gaussian distribution is given by .. math:: f(x) := \sqrt{\frac{\lambda}{2\pi x^3}} e^{-\frac{\lambda(x-\mu)^2}{2x\mu^2}} Parameters ========== mu : Positive number representing the mean. lambda : Positive number representing the shape parameter. Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import GaussianInverse, density, E, std, skewness >>> from sympy import Symbol, pprint >>> mu = Symbol("mu", positive=True) >>> lamda = Symbol("lambda", positive=True) >>> z = Symbol("z", positive=True) >>> X = GaussianInverse("x", mu, lamda) >>> D = density(X)(z) >>> pprint(D, use_unicode=False) 2 -lambda*(-mu + z) ------------------- 2 ___ ________ 2*mu *z \/ 2 *\/ lambda *e ------------------------------------- ____ 3/2 2*\/ pi *z >>> E(X) mu >>> std(X).expand() mu**(3/2)/sqrt(lambda) >>> skewness(X).expand() 3*sqrt(mu)/sqrt(lambda) References ========== .. [1] https://en.wikipedia.org/wiki/Inverse_Gaussian_distribution .. [2] http://mathworld.wolfram.com/InverseGaussianDistribution.html """ return rv(name, GaussianInverseDistribution, (mean, shape)) Wald = GaussianInverse #------------------------------------------------------------------------------- # Pareto distribution ---------------------------------------------------------- class ParetoDistribution(SingleContinuousDistribution): _argnames = ('xm', 'alpha') @property def set(self): return Interval(self.xm, oo) @staticmethod def check(xm, alpha): _value_check(xm > 0, "Xm must be positive") _value_check(alpha > 0, "Alpha must be positive") def pdf(self, x): xm, alpha = self.xm, self.alpha return alpha * xm**alpha / x**(alpha + 1) def _cdf(self, x): xm, alpha = self.xm, self.alpha return Piecewise( (S.One - xm**alpha/x**alpha, x>=xm), (0, True), ) def _moment_generating_function(self, t): xm, alpha = self.xm, self.alpha return alpha * (-xm*t)**alpha * uppergamma(-alpha, -xm*t) def _characteristic_function(self, t): xm, alpha = self.xm, self.alpha return alpha * (-I * xm * t) ** alpha * uppergamma(-alpha, -I * xm * t) def Pareto(name, xm, alpha): r""" Create a continuous random variable with the Pareto distribution. Explanation =========== The density of the Pareto distribution is given by .. math:: f(x) := \frac{\alpha\,x_m^\alpha}{x^{\alpha+1}} with :math:`x \in [x_m,\infty]`. Parameters ========== xm : Real number, `x_m > 0`, a scale alpha : Real number, `\alpha > 0`, a shape Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import Pareto, density >>> from sympy import Symbol >>> xm = Symbol("xm", positive=True) >>> beta = Symbol("beta", positive=True) >>> z = Symbol("z") >>> X = Pareto("x", xm, beta) >>> density(X)(z) beta*xm**beta*z**(-beta - 1) References ========== .. [1] https://en.wikipedia.org/wiki/Pareto_distribution .. [2] http://mathworld.wolfram.com/ParetoDistribution.html """ return rv(name, ParetoDistribution, (xm, alpha)) #------------------------------------------------------------------------------- # PowerFunction distribution --------------------------------------------------- class PowerFunctionDistribution(SingleContinuousDistribution): _argnames=('alpha','a','b') @property def set(self): return Interval(self.a, self.b) @staticmethod def check(alpha, a, b): _value_check(a.is_real, "Continuous Boundary parameter should be real.") _value_check(b.is_real, "Continuous Boundary parameter should be real.") _value_check(a < b, " 'a' the left Boundary must be smaller than 'b' the right Boundary." ) _value_check(alpha.is_positive, "Continuous Shape parameter should be positive.") def pdf(self, x): alpha, a, b = self.alpha, self.a, self.b num = alpha*(x - a)**(alpha - 1) den = (b - a)**alpha return num/den def PowerFunction(name, alpha, a, b): r""" Creates a continuous random variable with a Power Function Distribution. Explanation =========== The density of PowerFunction distribution is given by .. math:: f(x) := \frac{{\alpha}(x - a)^{\alpha - 1}}{(b - a)^{\alpha}} with :math:`x \in [a,b]`. Parameters ========== alpha: Positive number, `0 < alpha` the shape paramater a : Real number, :math:`-\infty < a` the left boundary b : Real number, :math:`a < b < \infty` the right boundary Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import PowerFunction, density, cdf, E, variance >>> from sympy import Symbol >>> alpha = Symbol("alpha", positive=True) >>> a = Symbol("a", real=True) >>> b = Symbol("b", real=True) >>> z = Symbol("z") >>> X = PowerFunction("X", 2, a, b) >>> density(X)(z) (-2*a + 2*z)/(-a + b)**2 >>> cdf(X)(z) Piecewise((a**2/(a**2 - 2*a*b + b**2) - 2*a*z/(a**2 - 2*a*b + b**2) + z**2/(a**2 - 2*a*b + b**2), a <= z), (0, True)) >>> alpha = 2 >>> a = 0 >>> b = 1 >>> Y = PowerFunction("Y", alpha, a, b) >>> E(Y) 2/3 >>> variance(Y) 1/18 References ========== .. [1] http://www.mathwave.com/help/easyfit/html/analyses/distributions/power_func.html """ return rv(name, PowerFunctionDistribution, (alpha, a, b)) #------------------------------------------------------------------------------- # QuadraticU distribution ------------------------------------------------------ class QuadraticUDistribution(SingleContinuousDistribution): _argnames = ('a', 'b') @property def set(self): return Interval(self.a, self.b) @staticmethod def check(a, b): _value_check(b > a, "Parameter b must be in range (%s, oo)."%(a)) def pdf(self, x): a, b = self.a, self.b alpha = 12 / (b-a)**3 beta = (a+b) / 2 return Piecewise( (alpha * (x-beta)**2, And(a<=x, x<=b)), (S.Zero, True)) def _moment_generating_function(self, t): a, b = self.a, self.b return -3 * (exp(a*t) * (4 + (a**2 + 2*a*(-2 + b) + b**2) * t) \ - exp(b*t) * (4 + (-4*b + (a + b)**2) * t)) / ((a-b)**3 * t**2) def _characteristic_function(self, t): a, b = self.a, self.b return -3*I*(exp(I*a*t*exp(I*b*t)) * (4*I - (-4*b + (a+b)**2)*t)) \ / ((a-b)**3 * t**2) def QuadraticU(name, a, b): r""" Create a Continuous Random Variable with a U-quadratic distribution. Explanation =========== The density of the U-quadratic distribution is given by .. math:: f(x) := \alpha (x-\beta)^2 with :math:`x \in [a,b]`. Parameters ========== a : Real number b : Real number, :math:`a < b` Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import QuadraticU, density >>> from sympy import Symbol, pprint >>> a = Symbol("a", real=True) >>> b = Symbol("b", real=True) >>> z = Symbol("z") >>> X = QuadraticU("x", a, b) >>> D = density(X)(z) >>> pprint(D, use_unicode=False) / 2 | / a b \ |12*|- - - - + z| | \ 2 2 / <----------------- for And(b >= z, a <= z) | 3 | (-a + b) | \ 0 otherwise References ========== .. [1] https://en.wikipedia.org/wiki/U-quadratic_distribution """ return rv(name, QuadraticUDistribution, (a, b)) #------------------------------------------------------------------------------- # RaisedCosine distribution ---------------------------------------------------- class RaisedCosineDistribution(SingleContinuousDistribution): _argnames = ('mu', 's') @property def set(self): return Interval(self.mu - self.s, self.mu + self.s) @staticmethod def check(mu, s): _value_check(s > 0, "s must be positive") def pdf(self, x): mu, s = self.mu, self.s return Piecewise( ((1+cos(pi*(x-mu)/s)) / (2*s), And(mu-s<=x, x<=mu+s)), (S.Zero, True)) def _characteristic_function(self, t): mu, s = self.mu, self.s return Piecewise((exp(-I*pi*mu/s)/2, Eq(t, -pi/s)), (exp(I*pi*mu/s)/2, Eq(t, pi/s)), (pi**2*sin(s*t)*exp(I*mu*t) / (s*t*(pi**2 - s**2*t**2)), True)) def _moment_generating_function(self, t): mu, s = self.mu, self.s return pi**2 * sinh(s*t) * exp(mu*t) / (s*t*(pi**2 + s**2*t**2)) def RaisedCosine(name, mu, s): r""" Create a Continuous Random Variable with a raised cosine distribution. Explanation =========== The density of the raised cosine distribution is given by .. math:: f(x) := \frac{1}{2s}\left(1+\cos\left(\frac{x-\mu}{s}\pi\right)\right) with :math:`x \in [\mu-s,\mu+s]`. Parameters ========== mu : Real number s : Real number, `s > 0` Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import RaisedCosine, density >>> from sympy import Symbol, pprint >>> mu = Symbol("mu", real=True) >>> s = Symbol("s", positive=True) >>> z = Symbol("z") >>> X = RaisedCosine("x", mu, s) >>> D = density(X)(z) >>> pprint(D, use_unicode=False) / /pi*(-mu + z)\ |cos|------------| + 1 | \ s / <--------------------- for And(z >= mu - s, z <= mu + s) | 2*s | \ 0 otherwise References ========== .. [1] https://en.wikipedia.org/wiki/Raised_cosine_distribution """ return rv(name, RaisedCosineDistribution, (mu, s)) #------------------------------------------------------------------------------- # Rayleigh distribution -------------------------------------------------------- class RayleighDistribution(SingleContinuousDistribution): _argnames = ('sigma',) set = Interval(0, oo) @staticmethod def check(sigma): _value_check(sigma > 0, "Scale parameter sigma must be positive.") def pdf(self, x): sigma = self.sigma return x/sigma**2*exp(-x**2/(2*sigma**2)) def _cdf(self, x): sigma = self.sigma return 1 - exp(-(x**2/(2*sigma**2))) def _characteristic_function(self, t): sigma = self.sigma return 1 - sigma*t*exp(-sigma**2*t**2/2) * sqrt(pi/2) * (erfi(sigma*t/sqrt(2)) - I) def _moment_generating_function(self, t): sigma = self.sigma return 1 + sigma*t*exp(sigma**2*t**2/2) * sqrt(pi/2) * (erf(sigma*t/sqrt(2)) + 1) def Rayleigh(name, sigma): r""" Create a continuous random variable with a Rayleigh distribution. Explanation =========== The density of the Rayleigh distribution is given by .. math :: f(x) := \frac{x}{\sigma^2} e^{-x^2/2\sigma^2} with :math:`x > 0`. Parameters ========== sigma : Real number, `\sigma > 0` Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import Rayleigh, density, E, variance >>> from sympy import Symbol >>> sigma = Symbol("sigma", positive=True) >>> z = Symbol("z") >>> X = Rayleigh("x", sigma) >>> density(X)(z) z*exp(-z**2/(2*sigma**2))/sigma**2 >>> E(X) sqrt(2)*sqrt(pi)*sigma/2 >>> variance(X) -pi*sigma**2/2 + 2*sigma**2 References ========== .. [1] https://en.wikipedia.org/wiki/Rayleigh_distribution .. [2] http://mathworld.wolfram.com/RayleighDistribution.html """ return rv(name, RayleighDistribution, (sigma, )) #------------------------------------------------------------------------------- # Reciprocal distribution -------------------------------------------------------- class ReciprocalDistribution(SingleContinuousDistribution): _argnames = ('a', 'b') @property def set(self): return Interval(self.a, self.b) @staticmethod def check(a, b): _value_check(a > 0, "Parameter > 0. a = %s"%a) _value_check((a < b), "Parameter b must be in range (%s, +oo]. b = %s"%(a, b)) def pdf(self, x): a, b = self.a, self.b return 1/(x*(log(b) - log(a))) def Reciprocal(name, a, b): r"""Creates a continuous random variable with a reciprocal distribution. Parameters ========== a : Real number, :math:`0 < a` b : Real number, :math:`a < b` Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import Reciprocal, density, cdf >>> from sympy import symbols >>> a, b, x = symbols('a, b, x', positive=True) >>> R = Reciprocal('R', a, b) >>> density(R)(x) 1/(x*(-log(a) + log(b))) >>> cdf(R)(x) Piecewise((log(a)/(log(a) - log(b)) - log(x)/(log(a) - log(b)), a <= x), (0, True)) Reference ========= .. [1] https://en.wikipedia.org/wiki/Reciprocal_distribution """ return rv(name, ReciprocalDistribution, (a, b)) #------------------------------------------------------------------------------- # Shifted Gompertz distribution ------------------------------------------------ class ShiftedGompertzDistribution(SingleContinuousDistribution): _argnames = ('b', 'eta') set = Interval(0, oo) @staticmethod def check(b, eta): _value_check(b > 0, "b must be positive") _value_check(eta > 0, "eta must be positive") def pdf(self, x): b, eta = self.b, self.eta return b*exp(-b*x)*exp(-eta*exp(-b*x))*(1+eta*(1-exp(-b*x))) def ShiftedGompertz(name, b, eta): r""" Create a continuous random variable with a Shifted Gompertz distribution. Explanation =========== The density of the Shifted Gompertz distribution is given by .. math:: f(x) := b e^{-b x} e^{-\eta \exp(-b x)} \left[1 + \eta(1 - e^(-bx)) \right] with :math: 'x \in [0, \inf)'. Parameters ========== b: Real number, 'b > 0' a scale eta: Real number, 'eta > 0' a shape Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import ShiftedGompertz, density >>> from sympy import Symbol >>> b = Symbol("b", positive=True) >>> eta = Symbol("eta", positive=True) >>> x = Symbol("x") >>> X = ShiftedGompertz("x", b, eta) >>> density(X)(x) b*(eta*(1 - exp(-b*x)) + 1)*exp(-b*x)*exp(-eta*exp(-b*x)) References ========== .. [1] https://en.wikipedia.org/wiki/Shifted_Gompertz_distribution """ return rv(name, ShiftedGompertzDistribution, (b, eta)) #------------------------------------------------------------------------------- # StudentT distribution -------------------------------------------------------- class StudentTDistribution(SingleContinuousDistribution): _argnames = ('nu',) set = Interval(-oo, oo) @staticmethod def check(nu): _value_check(nu > 0, "Degrees of freedom nu must be positive.") def pdf(self, x): nu = self.nu return 1/(sqrt(nu)*beta_fn(S.Half, nu/2))*(1 + x**2/nu)**(-(nu + 1)/2) def _cdf(self, x): nu = self.nu return S.Half + x*gamma((nu+1)/2)*hyper((S.Half, (nu+1)/2), (Rational(3, 2),), -x**2/nu)/(sqrt(pi*nu)*gamma(nu/2)) def _moment_generating_function(self, t): raise NotImplementedError('The moment generating function for the Student-T distribution is undefined.') def StudentT(name, nu): r""" Create a continuous random variable with a student's t distribution. Explanation =========== The density of the student's t distribution is given by .. math:: f(x) := \frac{\Gamma \left(\frac{\nu+1}{2} \right)} {\sqrt{\nu\pi}\Gamma \left(\frac{\nu}{2} \right)} \left(1+\frac{x^2}{\nu} \right)^{-\frac{\nu+1}{2}} Parameters ========== nu : Real number, `\nu > 0`, the degrees of freedom Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import StudentT, density, cdf >>> from sympy import Symbol, pprint >>> nu = Symbol("nu", positive=True) >>> z = Symbol("z") >>> X = StudentT("x", nu) >>> D = density(X)(z) >>> pprint(D, use_unicode=False) nu 1 - -- - - 2 2 / 2\ | z | |1 + --| \ nu/ ----------------- ____ / nu\ \/ nu *B|1/2, --| \ 2 / >>> cdf(X)(z) 1/2 + z*gamma(nu/2 + 1/2)*hyper((1/2, nu/2 + 1/2), (3/2,), -z**2/nu)/(sqrt(pi)*sqrt(nu)*gamma(nu/2)) References ========== .. [1] https://en.wikipedia.org/wiki/Student_t-distribution .. [2] http://mathworld.wolfram.com/Studentst-Distribution.html """ return rv(name, StudentTDistribution, (nu, )) #------------------------------------------------------------------------------- # Trapezoidal distribution ------------------------------------------------------ class TrapezoidalDistribution(SingleContinuousDistribution): _argnames = ('a', 'b', 'c', 'd') @property def set(self): return Interval(self.a, self.d) @staticmethod def check(a, b, c, d): _value_check(a < d, "Lower bound parameter a < %s. a = %s"%(d, a)) _value_check((a <= b, b < c), "Level start parameter b must be in range [%s, %s). b = %s"%(a, c, b)) _value_check((b < c, c <= d), "Level end parameter c must be in range (%s, %s]. c = %s"%(b, d, c)) _value_check(d >= c, "Upper bound parameter d > %s. d = %s"%(c, d)) def pdf(self, x): a, b, c, d = self.a, self.b, self.c, self.d return Piecewise( (2*(x-a) / ((b-a)*(d+c-a-b)), And(a <= x, x < b)), (2 / (d+c-a-b), And(b <= x, x < c)), (2*(d-x) / ((d-c)*(d+c-a-b)), And(c <= x, x <= d)), (S.Zero, True)) def Trapezoidal(name, a, b, c, d): r""" Create a continuous random variable with a trapezoidal distribution. Explanation =========== The density of the trapezoidal distribution is given by .. math:: f(x) := \begin{cases} 0 & \mathrm{for\ } x < a, \\ \frac{2(x-a)}{(b-a)(d+c-a-b)} & \mathrm{for\ } a \le x < b, \\ \frac{2}{d+c-a-b} & \mathrm{for\ } b \le x < c, \\ \frac{2(d-x)}{(d-c)(d+c-a-b)} & \mathrm{for\ } c \le x < d, \\ 0 & \mathrm{for\ } d < x. \end{cases} Parameters ========== a : Real number, :math:`a < d` b : Real number, :math:`a <= b < c` c : Real number, :math:`b < c <= d` d : Real number Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import Trapezoidal, density >>> from sympy import Symbol, pprint >>> a = Symbol("a") >>> b = Symbol("b") >>> c = Symbol("c") >>> d = Symbol("d") >>> z = Symbol("z") >>> X = Trapezoidal("x", a,b,c,d) >>> pprint(density(X)(z), use_unicode=False) / -2*a + 2*z |------------------------- for And(a <= z, b > z) |(-a + b)*(-a - b + c + d) | | 2 | -------------- for And(b <= z, c > z) < -a - b + c + d | | 2*d - 2*z |------------------------- for And(d >= z, c <= z) |(-c + d)*(-a - b + c + d) | \ 0 otherwise References ========== .. [1] https://en.wikipedia.org/wiki/Trapezoidal_distribution """ return rv(name, TrapezoidalDistribution, (a, b, c, d)) #------------------------------------------------------------------------------- # Triangular distribution ------------------------------------------------------ class TriangularDistribution(SingleContinuousDistribution): _argnames = ('a', 'b', 'c') @property def set(self): return Interval(self.a, self.b) @staticmethod def check(a, b, c): _value_check(b > a, "Parameter b > %s. b = %s"%(a, b)) _value_check((a <= c, c <= b), "Parameter c must be in range [%s, %s]. c = %s"%(a, b, c)) def pdf(self, x): a, b, c = self.a, self.b, self.c return Piecewise( (2*(x - a)/((b - a)*(c - a)), And(a <= x, x < c)), (2/(b - a), Eq(x, c)), (2*(b - x)/((b - a)*(b - c)), And(c < x, x <= b)), (S.Zero, True)) def _characteristic_function(self, t): a, b, c = self.a, self.b, self.c return -2 *((b-c) * exp(I*a*t) - (b-a) * exp(I*c*t) + (c-a) * exp(I*b*t)) / ((b-a)*(c-a)*(b-c)*t**2) def _moment_generating_function(self, t): a, b, c = self.a, self.b, self.c return 2 * ((b - c) * exp(a * t) - (b - a) * exp(c * t) + (c - a) * exp(b * t)) / ( (b - a) * (c - a) * (b - c) * t ** 2) def Triangular(name, a, b, c): r""" Create a continuous random variable with a triangular distribution. Explanation =========== The density of the triangular distribution is given by .. math:: f(x) := \begin{cases} 0 & \mathrm{for\ } x < a, \\ \frac{2(x-a)}{(b-a)(c-a)} & \mathrm{for\ } a \le x < c, \\ \frac{2}{b-a} & \mathrm{for\ } x = c, \\ \frac{2(b-x)}{(b-a)(b-c)} & \mathrm{for\ } c < x \le b, \\ 0 & \mathrm{for\ } b < x. \end{cases} Parameters ========== a : Real number, :math:`a \in \left(-\infty, \infty\right)` b : Real number, :math:`a < b` c : Real number, :math:`a \leq c \leq b` Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import Triangular, density >>> from sympy import Symbol, pprint >>> a = Symbol("a") >>> b = Symbol("b") >>> c = Symbol("c") >>> z = Symbol("z") >>> X = Triangular("x", a,b,c) >>> pprint(density(X)(z), use_unicode=False) / -2*a + 2*z |----------------- for And(a <= z, c > z) |(-a + b)*(-a + c) | | 2 | ------ for c = z < -a + b | | 2*b - 2*z |---------------- for And(b >= z, c < z) |(-a + b)*(b - c) | \ 0 otherwise References ========== .. [1] https://en.wikipedia.org/wiki/Triangular_distribution .. [2] http://mathworld.wolfram.com/TriangularDistribution.html """ return rv(name, TriangularDistribution, (a, b, c)) #------------------------------------------------------------------------------- # Uniform distribution --------------------------------------------------------- class UniformDistribution(SingleContinuousDistribution): _argnames = ('left', 'right') @property def set(self): return Interval(self.left, self.right) @staticmethod def check(left, right): _value_check(left < right, "Lower limit should be less than Upper limit.") def pdf(self, x): left, right = self.left, self.right return Piecewise( (S.One/(right - left), And(left <= x, x <= right)), (S.Zero, True) ) def _cdf(self, x): left, right = self.left, self.right return Piecewise( (S.Zero, x < left), ((x - left)/(right - left), x <= right), (S.One, True) ) def _characteristic_function(self, t): left, right = self.left, self.right return Piecewise(((exp(I*t*right) - exp(I*t*left)) / (I*t*(right - left)), Ne(t, 0)), (S.One, True)) def _moment_generating_function(self, t): left, right = self.left, self.right return Piecewise(((exp(t*right) - exp(t*left)) / (t * (right - left)), Ne(t, 0)), (S.One, True)) def expectation(self, expr, var, **kwargs): from sympy import Max, Min kwargs['evaluate'] = True result = SingleContinuousDistribution.expectation(self, expr, var, **kwargs) result = result.subs({Max(self.left, self.right): self.right, Min(self.left, self.right): self.left}) return result def Uniform(name, left, right): r""" Create a continuous random variable with a uniform distribution. Explanation =========== The density of the uniform distribution is given by .. math:: f(x) := \begin{cases} \frac{1}{b - a} & \text{for } x \in [a,b] \\ 0 & \text{otherwise} \end{cases} with :math:`x \in [a,b]`. Parameters ========== a : Real number, :math:`-\infty < a` the left boundary b : Real number, :math:`a < b < \infty` the right boundary Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import Uniform, density, cdf, E, variance >>> from sympy import Symbol, simplify >>> a = Symbol("a", negative=True) >>> b = Symbol("b", positive=True) >>> z = Symbol("z") >>> X = Uniform("x", a, b) >>> density(X)(z) Piecewise((1/(-a + b), (b >= z) & (a <= z)), (0, True)) >>> cdf(X)(z) Piecewise((0, a > z), ((-a + z)/(-a + b), b >= z), (1, True)) >>> E(X) a/2 + b/2 >>> simplify(variance(X)) a**2/12 - a*b/6 + b**2/12 References ========== .. [1] https://en.wikipedia.org/wiki/Uniform_distribution_%28continuous%29 .. [2] http://mathworld.wolfram.com/UniformDistribution.html """ return rv(name, UniformDistribution, (left, right)) #------------------------------------------------------------------------------- # UniformSum distribution ------------------------------------------------------ class UniformSumDistribution(SingleContinuousDistribution): _argnames = ('n',) @property def set(self): return Interval(0, self.n) @staticmethod def check(n): _value_check((n > 0, n.is_integer), "Parameter n must be positive integer.") def pdf(self, x): n = self.n k = Dummy("k") return 1/factorial( n - 1)*Sum((-1)**k*binomial(n, k)*(x - k)**(n - 1), (k, 0, floor(x))) def _cdf(self, x): n = self.n k = Dummy("k") return Piecewise((S.Zero, x < 0), (1/factorial(n)*Sum((-1)**k*binomial(n, k)*(x - k)**(n), (k, 0, floor(x))), x <= n), (S.One, True)) def _characteristic_function(self, t): return ((exp(I*t) - 1) / (I*t))**self.n def _moment_generating_function(self, t): return ((exp(t) - 1) / t)**self.n def UniformSum(name, n): r""" Create a continuous random variable with an Irwin-Hall distribution. Explanation =========== The probability distribution function depends on a single parameter $n$ which is an integer. The density of the Irwin-Hall distribution is given by .. math :: f(x) := \frac{1}{(n-1)!}\sum_{k=0}^{\left\lfloor x\right\rfloor}(-1)^k \binom{n}{k}(x-k)^{n-1} Parameters ========== n : A positive Integer, `n > 0` Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import UniformSum, density, cdf >>> from sympy import Symbol, pprint >>> n = Symbol("n", integer=True) >>> z = Symbol("z") >>> X = UniformSum("x", n) >>> D = density(X)(z) >>> pprint(D, use_unicode=False) floor(z) ___ \ ` \ k n - 1 /n\ ) (-1) *(-k + z) *| | / \k/ /__, k = 0 -------------------------------- (n - 1)! >>> cdf(X)(z) Piecewise((0, z < 0), (Sum((-1)**_k*(-_k + z)**n*binomial(n, _k), (_k, 0, floor(z)))/factorial(n), n >= z), (1, True)) Compute cdf with specific 'x' and 'n' values as follows : >>> cdf(UniformSum("x", 5), evaluate=False)(2).doit() 9/40 The argument evaluate=False prevents an attempt at evaluation of the sum for general n, before the argument 2 is passed. References ========== .. [1] https://en.wikipedia.org/wiki/Uniform_sum_distribution .. [2] http://mathworld.wolfram.com/UniformSumDistribution.html """ return rv(name, UniformSumDistribution, (n, )) #------------------------------------------------------------------------------- # VonMises distribution -------------------------------------------------------- class VonMisesDistribution(SingleContinuousDistribution): _argnames = ('mu', 'k') set = Interval(0, 2*pi) @staticmethod def check(mu, k): _value_check(k > 0, "k must be positive") def pdf(self, x): mu, k = self.mu, self.k return exp(k*cos(x-mu)) / (2*pi*besseli(0, k)) def VonMises(name, mu, k): r""" Create a Continuous Random Variable with a von Mises distribution. Explanation =========== The density of the von Mises distribution is given by .. math:: f(x) := \frac{e^{\kappa\cos(x-\mu)}}{2\pi I_0(\kappa)} with :math:`x \in [0,2\pi]`. Parameters ========== mu : Real number Measure of location. k : Real number Measure of concentration. Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import VonMises, density >>> from sympy import Symbol, pprint >>> mu = Symbol("mu") >>> k = Symbol("k", positive=True) >>> z = Symbol("z") >>> X = VonMises("x", mu, k) >>> D = density(X)(z) >>> pprint(D, use_unicode=False) k*cos(mu - z) e ------------------ 2*pi*besseli(0, k) References ========== .. [1] https://en.wikipedia.org/wiki/Von_Mises_distribution .. [2] http://mathworld.wolfram.com/vonMisesDistribution.html """ return rv(name, VonMisesDistribution, (mu, k)) #------------------------------------------------------------------------------- # Weibull distribution --------------------------------------------------------- class WeibullDistribution(SingleContinuousDistribution): _argnames = ('alpha', 'beta') set = Interval(0, oo) @staticmethod def check(alpha, beta): _value_check(alpha > 0, "Alpha must be positive") _value_check(beta > 0, "Beta must be positive") def pdf(self, x): alpha, beta = self.alpha, self.beta return beta * (x/alpha)**(beta - 1) * exp(-(x/alpha)**beta) / alpha def Weibull(name, alpha, beta): r""" Create a continuous random variable with a Weibull distribution. Explanation =========== The density of the Weibull distribution is given by .. math:: f(x) := \begin{cases} \frac{k}{\lambda}\left(\frac{x}{\lambda}\right)^{k-1} e^{-(x/\lambda)^{k}} & x\geq0\\ 0 & x<0 \end{cases} Parameters ========== lambda : Real number, :math:`\lambda > 0` a scale k : Real number, ``k > 0`` a shape Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import Weibull, density, E, variance >>> from sympy import Symbol, simplify >>> l = Symbol("lambda", positive=True) >>> k = Symbol("k", positive=True) >>> z = Symbol("z") >>> X = Weibull("x", l, k) >>> density(X)(z) k*(z/lambda)**(k - 1)*exp(-(z/lambda)**k)/lambda >>> simplify(E(X)) lambda*gamma(1 + 1/k) >>> simplify(variance(X)) lambda**2*(-gamma(1 + 1/k)**2 + gamma(1 + 2/k)) References ========== .. [1] https://en.wikipedia.org/wiki/Weibull_distribution .. [2] http://mathworld.wolfram.com/WeibullDistribution.html """ return rv(name, WeibullDistribution, (alpha, beta)) #------------------------------------------------------------------------------- # Wigner semicircle distribution ----------------------------------------------- class WignerSemicircleDistribution(SingleContinuousDistribution): _argnames = ('R',) @property def set(self): return Interval(-self.R, self.R) @staticmethod def check(R): _value_check(R > 0, "Radius R must be positive.") def pdf(self, x): R = self.R return 2/(pi*R**2)*sqrt(R**2 - x**2) def _characteristic_function(self, t): return Piecewise((2 * besselj(1, self.R*t) / (self.R*t), Ne(t, 0)), (S.One, True)) def _moment_generating_function(self, t): return Piecewise((2 * besseli(1, self.R*t) / (self.R*t), Ne(t, 0)), (S.One, True)) def WignerSemicircle(name, R): r""" Create a continuous random variable with a Wigner semicircle distribution. Explanation =========== The density of the Wigner semicircle distribution is given by .. math:: f(x) := \frac2{\pi R^2}\,\sqrt{R^2-x^2} with :math:`x \in [-R,R]`. Parameters ========== R : Real number, `R > 0`, the radius Returns ======= A `RandomSymbol`. Examples ======== >>> from sympy.stats import WignerSemicircle, density, E >>> from sympy import Symbol >>> R = Symbol("R", positive=True) >>> z = Symbol("z") >>> X = WignerSemicircle("x", R) >>> density(X)(z) 2*sqrt(R**2 - z**2)/(pi*R**2) >>> E(X) 0 References ========== .. [1] https://en.wikipedia.org/wiki/Wigner_semicircle_distribution .. [2] http://mathworld.wolfram.com/WignersSemicircleLaw.html """ return rv(name, WignerSemicircleDistribution, (R,))
df68be0bd1a6bb5ccb5ce84281db478c58e58e1803b39c469a577eb8b4c1da17
from collections import defaultdict from functools import reduce from sympy.core import (sympify, Basic, S, Expr, expand_mul, factor_terms, Mul, Dummy, igcd, FunctionClass, Add, symbols, Wild, expand) from sympy.core.cache import cacheit from sympy.core.compatibility import iterable, SYMPY_INTS from sympy.core.function import count_ops, _mexpand from sympy.core.numbers import I, Integer from sympy.functions import sin, cos, exp, cosh, tanh, sinh, tan, cot, coth from sympy.functions.elementary.hyperbolic import HyperbolicFunction from sympy.functions.elementary.trigonometric import TrigonometricFunction from sympy.polys import Poly, factor, cancel, parallel_poly_from_expr from sympy.polys.domains import ZZ from sympy.polys.polyerrors import PolificationFailed from sympy.polys.polytools import groebner from sympy.simplify.cse_main import cse from sympy.strategies.core import identity from sympy.strategies.tree import greedy from sympy.utilities.misc import debug def trigsimp_groebner(expr, hints=[], quick=False, order="grlex", polynomial=False): """ Simplify trigonometric expressions using a groebner basis algorithm. Explanation =========== This routine takes a fraction involving trigonometric or hyperbolic expressions, and tries to simplify it. The primary metric is the total degree. Some attempts are made to choose the simplest possible expression of the minimal degree, but this is non-rigorous, and also very slow (see the ``quick=True`` option). If ``polynomial`` is set to True, instead of simplifying numerator and denominator together, this function just brings numerator and denominator into a canonical form. This is much faster, but has potentially worse results. However, if the input is a polynomial, then the result is guaranteed to be an equivalent polynomial of minimal degree. The most important option is hints. Its entries can be any of the following: - a natural number - a function - an iterable of the form (func, var1, var2, ...) - anything else, interpreted as a generator A number is used to indicate that the search space should be increased. A function is used to indicate that said function is likely to occur in a simplified expression. An iterable is used indicate that func(var1 + var2 + ...) is likely to occur in a simplified . An additional generator also indicates that it is likely to occur. (See examples below). This routine carries out various computationally intensive algorithms. The option ``quick=True`` can be used to suppress one particularly slow step (at the expense of potentially more complicated results, but never at the expense of increased total degree). Examples ======== >>> from sympy.abc import x, y >>> from sympy import sin, tan, cos, sinh, cosh, tanh >>> from sympy.simplify.trigsimp import trigsimp_groebner Suppose you want to simplify ``sin(x)*cos(x)``. Naively, nothing happens: >>> ex = sin(x)*cos(x) >>> trigsimp_groebner(ex) sin(x)*cos(x) This is because ``trigsimp_groebner`` only looks for a simplification involving just ``sin(x)`` and ``cos(x)``. You can tell it to also try ``2*x`` by passing ``hints=[2]``: >>> trigsimp_groebner(ex, hints=[2]) sin(2*x)/2 >>> trigsimp_groebner(sin(x)**2 - cos(x)**2, hints=[2]) -cos(2*x) Increasing the search space this way can quickly become expensive. A much faster way is to give a specific expression that is likely to occur: >>> trigsimp_groebner(ex, hints=[sin(2*x)]) sin(2*x)/2 Hyperbolic expressions are similarly supported: >>> trigsimp_groebner(sinh(2*x)/sinh(x)) 2*cosh(x) Note how no hints had to be passed, since the expression already involved ``2*x``. The tangent function is also supported. You can either pass ``tan`` in the hints, to indicate that tan should be tried whenever cosine or sine are, or you can pass a specific generator: >>> trigsimp_groebner(sin(x)/cos(x), hints=[tan]) tan(x) >>> trigsimp_groebner(sinh(x)/cosh(x), hints=[tanh(x)]) tanh(x) Finally, you can use the iterable form to suggest that angle sum formulae should be tried: >>> ex = (tan(x) + tan(y))/(1 - tan(x)*tan(y)) >>> trigsimp_groebner(ex, hints=[(tan, x, y)]) tan(x + y) """ # TODO # - preprocess by replacing everything by funcs we can handle # - optionally use cot instead of tan # - more intelligent hinting. # For example, if the ideal is small, and we have sin(x), sin(y), # add sin(x + y) automatically... ? # - algebraic numbers ... # - expressions of lowest degree are not distinguished properly # e.g. 1 - sin(x)**2 # - we could try to order the generators intelligently, so as to influence # which monomials appear in the quotient basis # THEORY # ------ # Ratsimpmodprime above can be used to "simplify" a rational function # modulo a prime ideal. "Simplify" mainly means finding an equivalent # expression of lower total degree. # # We intend to use this to simplify trigonometric functions. To do that, # we need to decide (a) which ring to use, and (b) modulo which ideal to # simplify. In practice, (a) means settling on a list of "generators" # a, b, c, ..., such that the fraction we want to simplify is a rational # function in a, b, c, ..., with coefficients in ZZ (integers). # (2) means that we have to decide what relations to impose on the # generators. There are two practical problems: # (1) The ideal has to be *prime* (a technical term). # (2) The relations have to be polynomials in the generators. # # We typically have two kinds of generators: # - trigonometric expressions, like sin(x), cos(5*x), etc # - "everything else", like gamma(x), pi, etc. # # Since this function is trigsimp, we will concentrate on what to do with # trigonometric expressions. We can also simplify hyperbolic expressions, # but the extensions should be clear. # # One crucial point is that all *other* generators really should behave # like indeterminates. In particular if (say) "I" is one of them, then # in fact I**2 + 1 = 0 and we may and will compute non-sensical # expressions. However, we can work with a dummy and add the relation # I**2 + 1 = 0 to our ideal, then substitute back in the end. # # Now regarding trigonometric generators. We split them into groups, # according to the argument of the trigonometric functions. We want to # organise this in such a way that most trigonometric identities apply in # the same group. For example, given sin(x), cos(2*x) and cos(y), we would # group as [sin(x), cos(2*x)] and [cos(y)]. # # Our prime ideal will be built in three steps: # (1) For each group, compute a "geometrically prime" ideal of relations. # Geometrically prime means that it generates a prime ideal in # CC[gens], not just ZZ[gens]. # (2) Take the union of all the generators of the ideals for all groups. # By the geometric primality condition, this is still prime. # (3) Add further inter-group relations which preserve primality. # # Step (1) works as follows. We will isolate common factors in the # argument, so that all our generators are of the form sin(n*x), cos(n*x) # or tan(n*x), with n an integer. Suppose first there are no tan terms. # The ideal [sin(x)**2 + cos(x)**2 - 1] is geometrically prime, since # X**2 + Y**2 - 1 is irreducible over CC. # Now, if we have a generator sin(n*x), than we can, using trig identities, # express sin(n*x) as a polynomial in sin(x) and cos(x). We can add this # relation to the ideal, preserving geometric primality, since the quotient # ring is unchanged. # Thus we have treated all sin and cos terms. # For tan(n*x), we add a relation tan(n*x)*cos(n*x) - sin(n*x) = 0. # (This requires of course that we already have relations for cos(n*x) and # sin(n*x).) It is not obvious, but it seems that this preserves geometric # primality. # XXX A real proof would be nice. HELP! # Sketch that <S**2 + C**2 - 1, C*T - S> is a prime ideal of # CC[S, C, T]: # - it suffices to show that the projective closure in CP**3 is # irreducible # - using the half-angle substitutions, we can express sin(x), tan(x), # cos(x) as rational functions in tan(x/2) # - from this, we get a rational map from CP**1 to our curve # - this is a morphism, hence the curve is prime # # Step (2) is trivial. # # Step (3) works by adding selected relations of the form # sin(x + y) - sin(x)*cos(y) - sin(y)*cos(x), etc. Geometric primality is # preserved by the same argument as before. def parse_hints(hints): """Split hints into (n, funcs, iterables, gens).""" n = 1 funcs, iterables, gens = [], [], [] for e in hints: if isinstance(e, (SYMPY_INTS, Integer)): n = e elif isinstance(e, FunctionClass): funcs.append(e) elif iterable(e): iterables.append((e[0], e[1:])) # XXX sin(x+2y)? # Note: we go through polys so e.g. # sin(-x) -> -sin(x) -> sin(x) gens.extend(parallel_poly_from_expr( [e[0](x) for x in e[1:]] + [e[0](Add(*e[1:]))])[1].gens) else: gens.append(e) return n, funcs, iterables, gens def build_ideal(x, terms): """ Build generators for our ideal. ``Terms`` is an iterable with elements of the form (fn, coeff), indicating that we have a generator fn(coeff*x). If any of the terms is trigonometric, sin(x) and cos(x) are guaranteed to appear in terms. Similarly for hyperbolic functions. For tan(n*x), sin(n*x) and cos(n*x) are guaranteed. """ I = [] y = Dummy('y') for fn, coeff in terms: for c, s, t, rel in ( [cos, sin, tan, cos(x)**2 + sin(x)**2 - 1], [cosh, sinh, tanh, cosh(x)**2 - sinh(x)**2 - 1]): if coeff == 1 and fn in [c, s]: I.append(rel) elif fn == t: I.append(t(coeff*x)*c(coeff*x) - s(coeff*x)) elif fn in [c, s]: cn = fn(coeff*y).expand(trig=True).subs(y, x) I.append(fn(coeff*x) - cn) return list(set(I)) def analyse_gens(gens, hints): """ Analyse the generators ``gens``, using the hints ``hints``. The meaning of ``hints`` is described in the main docstring. Return a new list of generators, and also the ideal we should work with. """ # First parse the hints n, funcs, iterables, extragens = parse_hints(hints) debug('n=%s' % n, 'funcs:', funcs, 'iterables:', iterables, 'extragens:', extragens) # We just add the extragens to gens and analyse them as before gens = list(gens) gens.extend(extragens) # remove duplicates funcs = list(set(funcs)) iterables = list(set(iterables)) gens = list(set(gens)) # all the functions we can do anything with allfuncs = {sin, cos, tan, sinh, cosh, tanh} # sin(3*x) -> ((3, x), sin) trigterms = [(g.args[0].as_coeff_mul(), g.func) for g in gens if g.func in allfuncs] # Our list of new generators - start with anything that we cannot # work with (i.e. is not a trigonometric term) freegens = [g for g in gens if g.func not in allfuncs] newgens = [] trigdict = {} for (coeff, var), fn in trigterms: trigdict.setdefault(var, []).append((coeff, fn)) res = [] # the ideal for key, val in trigdict.items(): # We have now assembeled a dictionary. Its keys are common # arguments in trigonometric expressions, and values are lists of # pairs (fn, coeff). x0, (fn, coeff) in trigdict means that we # need to deal with fn(coeff*x0). We take the rational gcd of the # coeffs, call it ``gcd``. We then use x = x0/gcd as "base symbol", # all other arguments are integral multiples thereof. # We will build an ideal which works with sin(x), cos(x). # If hint tan is provided, also work with tan(x). Moreover, if # n > 1, also work with sin(k*x) for k <= n, and similarly for cos # (and tan if the hint is provided). Finally, any generators which # the ideal does not work with but we need to accommodate (either # because it was in expr or because it was provided as a hint) # we also build into the ideal. # This selection process is expressed in the list ``terms``. # build_ideal then generates the actual relations in our ideal, # from this list. fns = [x[1] for x in val] val = [x[0] for x in val] gcd = reduce(igcd, val) terms = [(fn, v/gcd) for (fn, v) in zip(fns, val)] fs = set(funcs + fns) for c, s, t in ([cos, sin, tan], [cosh, sinh, tanh]): if any(x in fs for x in (c, s, t)): fs.add(c) fs.add(s) for fn in fs: for k in range(1, n + 1): terms.append((fn, k)) extra = [] for fn, v in terms: if fn == tan: extra.append((sin, v)) extra.append((cos, v)) if fn in [sin, cos] and tan in fs: extra.append((tan, v)) if fn == tanh: extra.append((sinh, v)) extra.append((cosh, v)) if fn in [sinh, cosh] and tanh in fs: extra.append((tanh, v)) terms.extend(extra) x = gcd*Mul(*key) r = build_ideal(x, terms) res.extend(r) newgens.extend({fn(v*x) for fn, v in terms}) # Add generators for compound expressions from iterables for fn, args in iterables: if fn == tan: # Tan expressions are recovered from sin and cos. iterables.extend([(sin, args), (cos, args)]) elif fn == tanh: # Tanh expressions are recovered from sihn and cosh. iterables.extend([(sinh, args), (cosh, args)]) else: dummys = symbols('d:%i' % len(args), cls=Dummy) expr = fn( Add(*dummys)).expand(trig=True).subs(list(zip(dummys, args))) res.append(fn(Add(*args)) - expr) if myI in gens: res.append(myI**2 + 1) freegens.remove(myI) newgens.append(myI) return res, freegens, newgens myI = Dummy('I') expr = expr.subs(S.ImaginaryUnit, myI) subs = [(myI, S.ImaginaryUnit)] num, denom = cancel(expr).as_numer_denom() try: (pnum, pdenom), opt = parallel_poly_from_expr([num, denom]) except PolificationFailed: return expr debug('initial gens:', opt.gens) ideal, freegens, gens = analyse_gens(opt.gens, hints) debug('ideal:', ideal) debug('new gens:', gens, " -- len", len(gens)) debug('free gens:', freegens, " -- len", len(gens)) # NOTE we force the domain to be ZZ to stop polys from injecting generators # (which is usually a sign of a bug in the way we build the ideal) if not gens: return expr G = groebner(ideal, order=order, gens=gens, domain=ZZ) debug('groebner basis:', list(G), " -- len", len(G)) # If our fraction is a polynomial in the free generators, simplify all # coefficients separately: from sympy.simplify.ratsimp import ratsimpmodprime if freegens and pdenom.has_only_gens(*set(gens).intersection(pdenom.gens)): num = Poly(num, gens=gens+freegens).eject(*gens) res = [] for monom, coeff in num.terms(): ourgens = set(parallel_poly_from_expr([coeff, denom])[1].gens) # We compute the transitive closure of all generators that can # be reached from our generators through relations in the ideal. changed = True while changed: changed = False for p in ideal: p = Poly(p) if not ourgens.issuperset(p.gens) and \ not p.has_only_gens(*set(p.gens).difference(ourgens)): changed = True ourgens.update(p.exclude().gens) # NOTE preserve order! realgens = [x for x in gens if x in ourgens] # The generators of the ideal have now been (implicitly) split # into two groups: those involving ourgens and those that don't. # Since we took the transitive closure above, these two groups # live in subgrings generated by a *disjoint* set of variables. # Any sensible groebner basis algorithm will preserve this disjoint # structure (i.e. the elements of the groebner basis can be split # similarly), and and the two subsets of the groebner basis then # form groebner bases by themselves. (For the smaller generating # sets, of course.) ourG = [g.as_expr() for g in G.polys if g.has_only_gens(*ourgens.intersection(g.gens))] res.append(Mul(*[a**b for a, b in zip(freegens, monom)]) * \ ratsimpmodprime(coeff/denom, ourG, order=order, gens=realgens, quick=quick, domain=ZZ, polynomial=polynomial).subs(subs)) return Add(*res) # NOTE The following is simpler and has less assumptions on the # groebner basis algorithm. If the above turns out to be broken, # use this. return Add(*[Mul(*[a**b for a, b in zip(freegens, monom)]) * \ ratsimpmodprime(coeff/denom, list(G), order=order, gens=gens, quick=quick, domain=ZZ) for monom, coeff in num.terms()]) else: return ratsimpmodprime( expr, list(G), order=order, gens=freegens+gens, quick=quick, domain=ZZ, polynomial=polynomial).subs(subs) _trigs = (TrigonometricFunction, HyperbolicFunction) def trigsimp(expr, **opts): """ reduces expression by using known trig identities Explanation =========== method: - Determine the method to use. Valid choices are 'matching' (default), 'groebner', 'combined', and 'fu'. If 'matching', simplify the expression recursively by targeting common patterns. If 'groebner', apply an experimental groebner basis algorithm. In this case further options are forwarded to ``trigsimp_groebner``, please refer to its docstring. If 'combined', first run the groebner basis algorithm with small default parameters, then run the 'matching' algorithm. 'fu' runs the collection of trigonometric transformations described by Fu, et al. (see the `fu` docstring). Examples ======== >>> from sympy import trigsimp, sin, cos, log >>> from sympy.abc import x >>> e = 2*sin(x)**2 + 2*cos(x)**2 >>> trigsimp(e) 2 Simplification occurs wherever trigonometric functions are located. >>> trigsimp(log(e)) log(2) Using `method="groebner"` (or `"combined"`) might lead to greater simplification. The old trigsimp routine can be accessed as with method 'old'. >>> from sympy import coth, tanh >>> t = 3*tanh(x)**7 - 2/coth(x)**7 >>> trigsimp(t, method='old') == t True >>> trigsimp(t) tanh(x)**7 """ from sympy.simplify.fu import fu expr = sympify(expr) _eval_trigsimp = getattr(expr, '_eval_trigsimp', None) if _eval_trigsimp is not None: return _eval_trigsimp(**opts) old = opts.pop('old', False) if not old: opts.pop('deep', None) opts.pop('recursive', None) method = opts.pop('method', 'matching') else: method = 'old' def groebnersimp(ex, **opts): def traverse(e): if e.is_Atom: return e args = [traverse(x) for x in e.args] if e.is_Function or e.is_Pow: args = [trigsimp_groebner(x, **opts) for x in args] return e.func(*args) new = traverse(ex) if not isinstance(new, Expr): return new return trigsimp_groebner(new, **opts) trigsimpfunc = { 'fu': (lambda x: fu(x, **opts)), 'matching': (lambda x: futrig(x)), 'groebner': (lambda x: groebnersimp(x, **opts)), 'combined': (lambda x: futrig(groebnersimp(x, polynomial=True, hints=[2, tan]))), 'old': lambda x: trigsimp_old(x, **opts), }[method] return trigsimpfunc(expr) def exptrigsimp(expr): """ Simplifies exponential / trigonometric / hyperbolic functions. Examples ======== >>> from sympy import exptrigsimp, exp, cosh, sinh >>> from sympy.abc import z >>> exptrigsimp(exp(z) + exp(-z)) 2*cosh(z) >>> exptrigsimp(cosh(z) - sinh(z)) exp(-z) """ from sympy.simplify.fu import hyper_as_trig, TR2i from sympy.simplify.simplify import bottom_up def exp_trig(e): # select the better of e, and e rewritten in terms of exp or trig # functions choices = [e] if e.has(*_trigs): choices.append(e.rewrite(exp)) choices.append(e.rewrite(cos)) return min(*choices, key=count_ops) newexpr = bottom_up(expr, exp_trig) def f(rv): if not rv.is_Mul: return rv commutative_part, noncommutative_part = rv.args_cnc() # Since as_powers_dict loses order information, # if there is more than one noncommutative factor, # it should only be used to simplify the commutative part. if (len(noncommutative_part) > 1): return f(Mul(*commutative_part))*Mul(*noncommutative_part) rvd = rv.as_powers_dict() newd = rvd.copy() def signlog(expr, sign=S.One): if expr is S.Exp1: return sign, S.One elif isinstance(expr, exp) or (expr.is_Pow and expr.base == S.Exp1): return sign, expr.exp elif sign is S.One: return signlog(-expr, sign=-S.One) else: return None, None ee = rvd[S.Exp1] for k in rvd: if k.is_Add and len(k.args) == 2: # k == c*(1 + sign*E**x) c = k.args[0] sign, x = signlog(k.args[1]/c) if not x: continue m = rvd[k] newd[k] -= m if ee == -x*m/2: # sinh and cosh newd[S.Exp1] -= ee ee = 0 if sign == 1: newd[2*c*cosh(x/2)] += m else: newd[-2*c*sinh(x/2)] += m elif newd[1 - sign*S.Exp1**x] == -m: # tanh del newd[1 - sign*S.Exp1**x] if sign == 1: newd[-c/tanh(x/2)] += m else: newd[-c*tanh(x/2)] += m else: newd[1 + sign*S.Exp1**x] += m newd[c] += m return Mul(*[k**newd[k] for k in newd]) newexpr = bottom_up(newexpr, f) # sin/cos and sinh/cosh ratios to tan and tanh, respectively if newexpr.has(HyperbolicFunction): e, f = hyper_as_trig(newexpr) newexpr = f(TR2i(e)) if newexpr.has(TrigonometricFunction): newexpr = TR2i(newexpr) # can we ever generate an I where there was none previously? if not (newexpr.has(I) and not expr.has(I)): expr = newexpr return expr #-------------------- the old trigsimp routines --------------------- def trigsimp_old(expr, *, first=True, **opts): """ Reduces expression by using known trig identities. Notes ===== deep: - Apply trigsimp inside all objects with arguments recursive: - Use common subexpression elimination (cse()) and apply trigsimp recursively (this is quite expensive if the expression is large) method: - Determine the method to use. Valid choices are 'matching' (default), 'groebner', 'combined', 'fu' and 'futrig'. If 'matching', simplify the expression recursively by pattern matching. If 'groebner', apply an experimental groebner basis algorithm. In this case further options are forwarded to ``trigsimp_groebner``, please refer to its docstring. If 'combined', first run the groebner basis algorithm with small default parameters, then run the 'matching' algorithm. 'fu' runs the collection of trigonometric transformations described by Fu, et al. (see the `fu` docstring) while `futrig` runs a subset of Fu-transforms that mimic the behavior of `trigsimp`. compare: - show input and output from `trigsimp` and `futrig` when different, but returns the `trigsimp` value. Examples ======== >>> from sympy import trigsimp, sin, cos, log, cot >>> from sympy.abc import x >>> e = 2*sin(x)**2 + 2*cos(x)**2 >>> trigsimp(e, old=True) 2 >>> trigsimp(log(e), old=True) log(2*sin(x)**2 + 2*cos(x)**2) >>> trigsimp(log(e), deep=True, old=True) log(2) Using `method="groebner"` (or `"combined"`) can sometimes lead to a lot more simplification: >>> e = (-sin(x) + 1)/cos(x) + cos(x)/(-sin(x) + 1) >>> trigsimp(e, old=True) (1 - sin(x))/cos(x) + cos(x)/(1 - sin(x)) >>> trigsimp(e, method="groebner", old=True) 2/cos(x) >>> trigsimp(1/cot(x)**2, compare=True, old=True) futrig: tan(x)**2 cot(x)**(-2) """ old = expr if first: if not expr.has(*_trigs): return expr trigsyms = set().union(*[t.free_symbols for t in expr.atoms(*_trigs)]) if len(trigsyms) > 1: from sympy.simplify.simplify import separatevars d = separatevars(expr) if d.is_Mul: d = separatevars(d, dict=True) or d if isinstance(d, dict): expr = 1 for k, v in d.items(): # remove hollow factoring was = v v = expand_mul(v) opts['first'] = False vnew = trigsimp(v, **opts) if vnew == v: vnew = was expr *= vnew old = expr else: if d.is_Add: for s in trigsyms: r, e = expr.as_independent(s) if r: opts['first'] = False expr = r + trigsimp(e, **opts) if not expr.is_Add: break old = expr recursive = opts.pop('recursive', False) deep = opts.pop('deep', False) method = opts.pop('method', 'matching') def groebnersimp(ex, deep, **opts): def traverse(e): if e.is_Atom: return e args = [traverse(x) for x in e.args] if e.is_Function or e.is_Pow: args = [trigsimp_groebner(x, **opts) for x in args] return e.func(*args) if deep: ex = traverse(ex) return trigsimp_groebner(ex, **opts) trigsimpfunc = { 'matching': (lambda x, d: _trigsimp(x, d)), 'groebner': (lambda x, d: groebnersimp(x, d, **opts)), 'combined': (lambda x, d: _trigsimp(groebnersimp(x, d, polynomial=True, hints=[2, tan]), d)) }[method] if recursive: w, g = cse(expr) g = trigsimpfunc(g[0], deep) for sub in reversed(w): g = g.subs(sub[0], sub[1]) g = trigsimpfunc(g, deep) result = g else: result = trigsimpfunc(expr, deep) if opts.get('compare', False): f = futrig(old) if f != result: print('\tfutrig:', f) return result def _dotrig(a, b): """Helper to tell whether ``a`` and ``b`` have the same sorts of symbols in them -- no need to test hyperbolic patterns against expressions that have no hyperbolics in them.""" return a.func == b.func and ( a.has(TrigonometricFunction) and b.has(TrigonometricFunction) or a.has(HyperbolicFunction) and b.has(HyperbolicFunction)) _trigpat = None def _trigpats(): global _trigpat a, b, c = symbols('a b c', cls=Wild) d = Wild('d', commutative=False) # for the simplifications like sinh/cosh -> tanh: # DO NOT REORDER THE FIRST 14 since these are assumed to be in this # order in _match_div_rewrite. matchers_division = ( (a*sin(b)**c/cos(b)**c, a*tan(b)**c, sin(b), cos(b)), (a*tan(b)**c*cos(b)**c, a*sin(b)**c, sin(b), cos(b)), (a*cot(b)**c*sin(b)**c, a*cos(b)**c, sin(b), cos(b)), (a*tan(b)**c/sin(b)**c, a/cos(b)**c, sin(b), cos(b)), (a*cot(b)**c/cos(b)**c, a/sin(b)**c, sin(b), cos(b)), (a*cot(b)**c*tan(b)**c, a, sin(b), cos(b)), (a*(cos(b) + 1)**c*(cos(b) - 1)**c, a*(-sin(b)**2)**c, cos(b) + 1, cos(b) - 1), (a*(sin(b) + 1)**c*(sin(b) - 1)**c, a*(-cos(b)**2)**c, sin(b) + 1, sin(b) - 1), (a*sinh(b)**c/cosh(b)**c, a*tanh(b)**c, S.One, S.One), (a*tanh(b)**c*cosh(b)**c, a*sinh(b)**c, S.One, S.One), (a*coth(b)**c*sinh(b)**c, a*cosh(b)**c, S.One, S.One), (a*tanh(b)**c/sinh(b)**c, a/cosh(b)**c, S.One, S.One), (a*coth(b)**c/cosh(b)**c, a/sinh(b)**c, S.One, S.One), (a*coth(b)**c*tanh(b)**c, a, S.One, S.One), (c*(tanh(a) + tanh(b))/(1 + tanh(a)*tanh(b)), tanh(a + b)*c, S.One, S.One), ) matchers_add = ( (c*sin(a)*cos(b) + c*cos(a)*sin(b) + d, sin(a + b)*c + d), (c*cos(a)*cos(b) - c*sin(a)*sin(b) + d, cos(a + b)*c + d), (c*sin(a)*cos(b) - c*cos(a)*sin(b) + d, sin(a - b)*c + d), (c*cos(a)*cos(b) + c*sin(a)*sin(b) + d, cos(a - b)*c + d), (c*sinh(a)*cosh(b) + c*sinh(b)*cosh(a) + d, sinh(a + b)*c + d), (c*cosh(a)*cosh(b) + c*sinh(a)*sinh(b) + d, cosh(a + b)*c + d), ) # for cos(x)**2 + sin(x)**2 -> 1 matchers_identity = ( (a*sin(b)**2, a - a*cos(b)**2), (a*tan(b)**2, a*(1/cos(b))**2 - a), (a*cot(b)**2, a*(1/sin(b))**2 - a), (a*sin(b + c), a*(sin(b)*cos(c) + sin(c)*cos(b))), (a*cos(b + c), a*(cos(b)*cos(c) - sin(b)*sin(c))), (a*tan(b + c), a*((tan(b) + tan(c))/(1 - tan(b)*tan(c)))), (a*sinh(b)**2, a*cosh(b)**2 - a), (a*tanh(b)**2, a - a*(1/cosh(b))**2), (a*coth(b)**2, a + a*(1/sinh(b))**2), (a*sinh(b + c), a*(sinh(b)*cosh(c) + sinh(c)*cosh(b))), (a*cosh(b + c), a*(cosh(b)*cosh(c) + sinh(b)*sinh(c))), (a*tanh(b + c), a*((tanh(b) + tanh(c))/(1 + tanh(b)*tanh(c)))), ) # Reduce any lingering artifacts, such as sin(x)**2 changing # to 1-cos(x)**2 when sin(x)**2 was "simpler" artifacts = ( (a - a*cos(b)**2 + c, a*sin(b)**2 + c, cos), (a - a*(1/cos(b))**2 + c, -a*tan(b)**2 + c, cos), (a - a*(1/sin(b))**2 + c, -a*cot(b)**2 + c, sin), (a - a*cosh(b)**2 + c, -a*sinh(b)**2 + c, cosh), (a - a*(1/cosh(b))**2 + c, a*tanh(b)**2 + c, cosh), (a + a*(1/sinh(b))**2 + c, a*coth(b)**2 + c, sinh), # same as above but with noncommutative prefactor (a*d - a*d*cos(b)**2 + c, a*d*sin(b)**2 + c, cos), (a*d - a*d*(1/cos(b))**2 + c, -a*d*tan(b)**2 + c, cos), (a*d - a*d*(1/sin(b))**2 + c, -a*d*cot(b)**2 + c, sin), (a*d - a*d*cosh(b)**2 + c, -a*d*sinh(b)**2 + c, cosh), (a*d - a*d*(1/cosh(b))**2 + c, a*d*tanh(b)**2 + c, cosh), (a*d + a*d*(1/sinh(b))**2 + c, a*d*coth(b)**2 + c, sinh), ) _trigpat = (a, b, c, d, matchers_division, matchers_add, matchers_identity, artifacts) return _trigpat def _replace_mul_fpowxgpow(expr, f, g, rexp, h, rexph): """Helper for _match_div_rewrite. Replace f(b_)**c_*g(b_)**(rexp(c_)) with h(b)**rexph(c) if f(b_) and g(b_) are both positive or if c_ is an integer. """ # assert expr.is_Mul and expr.is_commutative and f != g fargs = defaultdict(int) gargs = defaultdict(int) args = [] for x in expr.args: if x.is_Pow or x.func in (f, g): b, e = x.as_base_exp() if b.is_positive or e.is_integer: if b.func == f: fargs[b.args[0]] += e continue elif b.func == g: gargs[b.args[0]] += e continue args.append(x) common = set(fargs) & set(gargs) hit = False while common: key = common.pop() fe = fargs.pop(key) ge = gargs.pop(key) if fe == rexp(ge): args.append(h(key)**rexph(fe)) hit = True else: fargs[key] = fe gargs[key] = ge if not hit: return expr while fargs: key, e = fargs.popitem() args.append(f(key)**e) while gargs: key, e = gargs.popitem() args.append(g(key)**e) return Mul(*args) _idn = lambda x: x _midn = lambda x: -x _one = lambda x: S.One def _match_div_rewrite(expr, i): """helper for __trigsimp""" if i == 0: expr = _replace_mul_fpowxgpow(expr, sin, cos, _midn, tan, _idn) elif i == 1: expr = _replace_mul_fpowxgpow(expr, tan, cos, _idn, sin, _idn) elif i == 2: expr = _replace_mul_fpowxgpow(expr, cot, sin, _idn, cos, _idn) elif i == 3: expr = _replace_mul_fpowxgpow(expr, tan, sin, _midn, cos, _midn) elif i == 4: expr = _replace_mul_fpowxgpow(expr, cot, cos, _midn, sin, _midn) elif i == 5: expr = _replace_mul_fpowxgpow(expr, cot, tan, _idn, _one, _idn) # i in (6, 7) is skipped elif i == 8: expr = _replace_mul_fpowxgpow(expr, sinh, cosh, _midn, tanh, _idn) elif i == 9: expr = _replace_mul_fpowxgpow(expr, tanh, cosh, _idn, sinh, _idn) elif i == 10: expr = _replace_mul_fpowxgpow(expr, coth, sinh, _idn, cosh, _idn) elif i == 11: expr = _replace_mul_fpowxgpow(expr, tanh, sinh, _midn, cosh, _midn) elif i == 12: expr = _replace_mul_fpowxgpow(expr, coth, cosh, _midn, sinh, _midn) elif i == 13: expr = _replace_mul_fpowxgpow(expr, coth, tanh, _idn, _one, _idn) else: return None return expr def _trigsimp(expr, deep=False): # protect the cache from non-trig patterns; we only allow # trig patterns to enter the cache if expr.has(*_trigs): return __trigsimp(expr, deep) return expr @cacheit def __trigsimp(expr, deep=False): """recursive helper for trigsimp""" from sympy.simplify.fu import TR10i if _trigpat is None: _trigpats() a, b, c, d, matchers_division, matchers_add, \ matchers_identity, artifacts = _trigpat if expr.is_Mul: # do some simplifications like sin/cos -> tan: if not expr.is_commutative: com, nc = expr.args_cnc() expr = _trigsimp(Mul._from_args(com), deep)*Mul._from_args(nc) else: for i, (pattern, simp, ok1, ok2) in enumerate(matchers_division): if not _dotrig(expr, pattern): continue newexpr = _match_div_rewrite(expr, i) if newexpr is not None: if newexpr != expr: expr = newexpr break else: continue # use SymPy matching instead res = expr.match(pattern) if res and res.get(c, 0): if not res[c].is_integer: ok = ok1.subs(res) if not ok.is_positive: continue ok = ok2.subs(res) if not ok.is_positive: continue # if "a" contains any of trig or hyperbolic funcs with # argument "b" then skip the simplification if any(w.args[0] == res[b] for w in res[a].atoms( TrigonometricFunction, HyperbolicFunction)): continue # simplify and finish: expr = simp.subs(res) break # process below if expr.is_Add: args = [] for term in expr.args: if not term.is_commutative: com, nc = term.args_cnc() nc = Mul._from_args(nc) term = Mul._from_args(com) else: nc = S.One term = _trigsimp(term, deep) for pattern, result in matchers_identity: res = term.match(pattern) if res is not None: term = result.subs(res) break args.append(term*nc) if args != expr.args: expr = Add(*args) expr = min(expr, expand(expr), key=count_ops) if expr.is_Add: for pattern, result in matchers_add: if not _dotrig(expr, pattern): continue expr = TR10i(expr) if expr.has(HyperbolicFunction): res = expr.match(pattern) # if "d" contains any trig or hyperbolic funcs with # argument "a" or "b" then skip the simplification; # this isn't perfect -- see tests if res is None or not (a in res and b in res) or any( w.args[0] in (res[a], res[b]) for w in res[d].atoms( TrigonometricFunction, HyperbolicFunction)): continue expr = result.subs(res) break # Reduce any lingering artifacts, such as sin(x)**2 changing # to 1 - cos(x)**2 when sin(x)**2 was "simpler" for pattern, result, ex in artifacts: if not _dotrig(expr, pattern): continue # Substitute a new wild that excludes some function(s) # to help influence a better match. This is because # sometimes, for example, 'a' would match sec(x)**2 a_t = Wild('a', exclude=[ex]) pattern = pattern.subs(a, a_t) result = result.subs(a, a_t) m = expr.match(pattern) was = None while m and was != expr: was = expr if m[a_t] == 0 or \ -m[a_t] in m[c].args or m[a_t] + m[c] == 0: break if d in m and m[a_t]*m[d] + m[c] == 0: break expr = result.subs(m) m = expr.match(pattern) m.setdefault(c, S.Zero) elif expr.is_Mul or expr.is_Pow or deep and expr.args: expr = expr.func(*[_trigsimp(a, deep) for a in expr.args]) try: if not expr.has(*_trigs): raise TypeError e = expr.atoms(exp) new = expr.rewrite(exp, deep=deep) if new == e: raise TypeError fnew = factor(new) if fnew != new: new = sorted([new, factor(new)], key=count_ops)[0] # if all exp that were introduced disappeared then accept it if not (new.atoms(exp) - e): expr = new except TypeError: pass return expr #------------------- end of old trigsimp routines -------------------- def futrig(e, *, hyper=True, **kwargs): """Return simplified ``e`` using Fu-like transformations. This is not the "Fu" algorithm. This is called by default from ``trigsimp``. By default, hyperbolics subexpressions will be simplified, but this can be disabled by setting ``hyper=False``. Examples ======== >>> from sympy import trigsimp, tan, sinh, tanh >>> from sympy.simplify.trigsimp import futrig >>> from sympy.abc import x >>> trigsimp(1/tan(x)**2) tan(x)**(-2) >>> futrig(sinh(x)/tanh(x)) cosh(x) """ from sympy.simplify.fu import hyper_as_trig from sympy.simplify.simplify import bottom_up e = sympify(e) if not isinstance(e, Basic): return e if not e.args: return e old = e e = bottom_up(e, _futrig) if hyper and e.has(HyperbolicFunction): e, f = hyper_as_trig(e) e = f(bottom_up(e, _futrig)) if e != old and e.is_Mul and e.args[0].is_Rational: # redistribute leading coeff on 2-arg Add e = Mul(*e.as_coeff_Mul()) return e def _futrig(e): """Helper for futrig.""" from sympy.simplify.fu import ( TR1, TR2, TR3, TR2i, TR10, L, TR10i, TR8, TR6, TR15, TR16, TR111, TR5, TRmorrie, TR11, _TR11, TR14, TR22, TR12) from sympy.core.compatibility import _nodes if not e.has(TrigonometricFunction): return e if e.is_Mul: coeff, e = e.as_independent(TrigonometricFunction) else: coeff = None Lops = lambda x: (L(x), x.count_ops(), _nodes(x), len(x.args), x.is_Add) trigs = lambda x: x.has(TrigonometricFunction) tree = [identity, ( TR3, # canonical angles TR1, # sec-csc -> cos-sin TR12, # expand tan of sum lambda x: _eapply(factor, x, trigs), TR2, # tan-cot -> sin-cos [identity, lambda x: _eapply(_mexpand, x, trigs)], TR2i, # sin-cos ratio -> tan lambda x: _eapply(lambda i: factor(i.normal()), x, trigs), TR14, # factored identities TR5, # sin-pow -> cos_pow TR10, # sin-cos of sums -> sin-cos prod TR11, _TR11, TR6, # reduce double angles and rewrite cos pows lambda x: _eapply(factor, x, trigs), TR14, # factored powers of identities [identity, lambda x: _eapply(_mexpand, x, trigs)], TR10i, # sin-cos products > sin-cos of sums TRmorrie, [identity, TR8], # sin-cos products -> sin-cos of sums [identity, lambda x: TR2i(TR2(x))], # tan -> sin-cos -> tan [ lambda x: _eapply(expand_mul, TR5(x), trigs), lambda x: _eapply( expand_mul, TR15(x), trigs)], # pos/neg powers of sin [ lambda x: _eapply(expand_mul, TR6(x), trigs), lambda x: _eapply( expand_mul, TR16(x), trigs)], # pos/neg powers of cos TR111, # tan, sin, cos to neg power -> cot, csc, sec [identity, TR2i], # sin-cos ratio to tan [identity, lambda x: _eapply( expand_mul, TR22(x), trigs)], # tan-cot to sec-csc TR1, TR2, TR2i, [identity, lambda x: _eapply( factor_terms, TR12(x), trigs)], # expand tan of sum )] e = greedy(tree, objective=Lops)(e) if coeff is not None: e = coeff * e return e def _is_Expr(e): """_eapply helper to tell whether ``e`` and all its args are Exprs.""" from sympy import Derivative if isinstance(e, Derivative): return _is_Expr(e.expr) if not isinstance(e, Expr): return False return all(_is_Expr(i) for i in e.args) def _eapply(func, e, cond=None): """Apply ``func`` to ``e`` if all args are Exprs else only apply it to those args that *are* Exprs.""" if not isinstance(e, Expr): return e if _is_Expr(e) or not e.args: return func(e) return e.func(*[ _eapply(func, ei) if (cond is None or cond(ei)) else ei for ei in e.args])
0f5415349ab1c496f544b4b6f8336c924535aa8e438ec21f2bdfb652b15d39a2
""" This module contains functions to: - solve a single equation for a single variable, in any domain either real or complex. - solve a single transcendental equation for a single variable in any domain either real or complex. (currently supports solving in real domain only) - solve a system of linear equations with N variables and M equations. - solve a system of Non Linear Equations with N variables and M equations """ from sympy.core.sympify import sympify from sympy.core import (S, Pow, Dummy, pi, Expr, Wild, Mul, Equality, Add) from sympy.core.containers import Tuple from sympy.core.numbers import I, Number, Rational, oo from sympy.core.function import (Lambda, expand_complex, AppliedUndef, expand_log) from sympy.core.mod import Mod from sympy.core.numbers import igcd from sympy.core.relational import Eq, Ne, Relational from sympy.core.symbol import Symbol, _uniquely_named_symbol from sympy.core.sympify import _sympify from sympy.simplify.simplify import simplify, fraction, trigsimp from sympy.simplify import powdenest, logcombine from sympy.functions import (log, Abs, tan, cot, sin, cos, sec, csc, exp, acos, asin, acsc, asec, arg, piecewise_fold, Piecewise) from sympy.functions.elementary.trigonometric import (TrigonometricFunction, HyperbolicFunction) from sympy.functions.elementary.miscellaneous import real_root from sympy.logic.boolalg import And from sympy.sets import (FiniteSet, EmptySet, imageset, Interval, Intersection, Union, ConditionSet, ImageSet, Complement, Contains) from sympy.sets.sets import Set, ProductSet from sympy.matrices import Matrix, MatrixBase from sympy.ntheory import totient from sympy.ntheory.factor_ import divisors from sympy.ntheory.residue_ntheory import discrete_log, nthroot_mod from sympy.polys import (roots, Poly, degree, together, PolynomialError, RootOf, factor, lcm, gcd) from sympy.polys.polyerrors import CoercionFailed from sympy.polys.polytools import invert from sympy.polys.solvers import (sympy_eqs_to_ring, solve_lin_sys, PolyNonlinearError) from sympy.polys.matrices.linsolve import _linsolve from sympy.solvers.solvers import (checksol, denoms, unrad, _simple_dens, recast_to_symbols) from sympy.solvers.polysys import solve_poly_system from sympy.solvers.inequalities import solve_univariate_inequality from sympy.utilities import filldedent from sympy.utilities.iterables import numbered_symbols, has_dups from sympy.calculus.util import periodicity, continuous_domain from sympy.core.compatibility import ordered, default_sort_key, is_sequence from types import GeneratorType from collections import defaultdict class NonlinearError(ValueError): """Raised when unexpectedly encountering nonlinear equations""" pass _rc = Dummy("R", real=True), Dummy("C", complex=True) def _masked(f, *atoms): """Return ``f``, with all objects given by ``atoms`` replaced with Dummy symbols, ``d``, and the list of replacements, ``(d, e)``, where ``e`` is an object of type given by ``atoms`` in which any other instances of atoms have been recursively replaced with Dummy symbols, too. The tuples are ordered so that if they are applied in sequence, the origin ``f`` will be restored. Examples ======== >>> from sympy import cos >>> from sympy.abc import x >>> from sympy.solvers.solveset import _masked >>> f = cos(cos(x) + 1) >>> f, reps = _masked(cos(1 + cos(x)), cos) >>> f _a1 >>> reps [(_a1, cos(_a0 + 1)), (_a0, cos(x))] >>> for d, e in reps: ... f = f.xreplace({d: e}) >>> f cos(cos(x) + 1) """ sym = numbered_symbols('a', cls=Dummy, real=True) mask = [] for a in ordered(f.atoms(*atoms)): for i in mask: a = a.replace(*i) mask.append((a, next(sym))) for i, (o, n) in enumerate(mask): f = f.replace(o, n) mask[i] = (n, o) mask = list(reversed(mask)) return f, mask def _invert(f_x, y, x, domain=S.Complexes): r""" Reduce the complex valued equation ``f(x) = y`` to a set of equations ``{g(x) = h_1(y), g(x) = h_2(y), ..., g(x) = h_n(y) }`` where ``g(x)`` is a simpler function than ``f(x)``. The return value is a tuple ``(g(x), set_h)``, where ``g(x)`` is a function of ``x`` and ``set_h`` is the set of function ``{h_1(y), h_2(y), ..., h_n(y)}``. Here, ``y`` is not necessarily a symbol. The ``set_h`` contains the functions, along with the information about the domain in which they are valid, through set operations. For instance, if ``y = Abs(x) - n`` is inverted in the real domain, then ``set_h`` is not simply `{-n, n}` as the nature of `n` is unknown; rather, it is: `Intersection([0, oo) {n}) U Intersection((-oo, 0], {-n})` By default, the complex domain is used which means that inverting even seemingly simple functions like ``exp(x)`` will give very different results from those obtained in the real domain. (In the case of ``exp(x)``, the inversion via ``log`` is multi-valued in the complex domain, having infinitely many branches.) If you are working with real values only (or you are not sure which function to use) you should probably set the domain to ``S.Reals`` (or use `invert\_real` which does that automatically). Examples ======== >>> from sympy.solvers.solveset import invert_complex, invert_real >>> from sympy.abc import x, y >>> from sympy import exp When does exp(x) == y? >>> invert_complex(exp(x), y, x) (x, ImageSet(Lambda(_n, I*(2*_n*pi + arg(y)) + log(Abs(y))), Integers)) >>> invert_real(exp(x), y, x) (x, Intersection(FiniteSet(log(y)), Reals)) When does exp(x) == 1? >>> invert_complex(exp(x), 1, x) (x, ImageSet(Lambda(_n, 2*_n*I*pi), Integers)) >>> invert_real(exp(x), 1, x) (x, FiniteSet(0)) See Also ======== invert_real, invert_complex """ x = sympify(x) if not x.is_Symbol: raise ValueError("x must be a symbol") f_x = sympify(f_x) if x not in f_x.free_symbols: raise ValueError("Inverse of constant function doesn't exist") y = sympify(y) if x in y.free_symbols: raise ValueError("y should be independent of x ") if domain.is_subset(S.Reals): x1, s = _invert_real(f_x, FiniteSet(y), x) else: x1, s = _invert_complex(f_x, FiniteSet(y), x) if not isinstance(s, FiniteSet) or x1 != x: return x1, s # Avoid adding gratuitous intersections with S.Complexes. Actual # conditions should be handled by the respective inverters. if domain is S.Complexes: return x1, s else: return x1, s.intersection(domain) invert_complex = _invert def invert_real(f_x, y, x, domain=S.Reals): """ Inverts a real-valued function. Same as _invert, but sets the domain to ``S.Reals`` before inverting. """ return _invert(f_x, y, x, domain) def _invert_real(f, g_ys, symbol): """Helper function for _invert.""" if f == symbol: return (f, g_ys) n = Dummy('n', real=True) if isinstance(f, exp) or (f.is_Pow and f.base == S.Exp1): return _invert_real(f.exp, imageset(Lambda(n, log(n)), g_ys), symbol) if hasattr(f, 'inverse') and f.inverse() is not None and not isinstance(f, ( TrigonometricFunction, HyperbolicFunction, )): if len(f.args) > 1: raise ValueError("Only functions with one argument are supported.") return _invert_real(f.args[0], imageset(Lambda(n, f.inverse()(n)), g_ys), symbol) if isinstance(f, Abs): return _invert_abs(f.args[0], g_ys, symbol) if f.is_Add: # f = g + h g, h = f.as_independent(symbol) if g is not S.Zero: return _invert_real(h, imageset(Lambda(n, n - g), g_ys), symbol) if f.is_Mul: # f = g*h g, h = f.as_independent(symbol) if g is not S.One: return _invert_real(h, imageset(Lambda(n, n/g), g_ys), symbol) if f.is_Pow: base, expo = f.args base_has_sym = base.has(symbol) expo_has_sym = expo.has(symbol) if not expo_has_sym: if expo.is_rational: num, den = expo.as_numer_denom() if den % 2 == 0 and num % 2 == 1 and den.is_zero is False: root = Lambda(n, real_root(n, expo)) g_ys_pos = g_ys & Interval(0, oo) res = imageset(root, g_ys_pos) base_positive = solveset(base >= 0, symbol, S.Reals) _inv, _set = _invert_real(base, res, symbol) return (_inv, _set.intersect(base_positive)) if den % 2 == 1: root = Lambda(n, real_root(n, expo)) res = imageset(root, g_ys) if num % 2 == 0: neg_res = imageset(Lambda(n, -n), res) return _invert_real(base, res + neg_res, symbol) if num % 2 == 1: return _invert_real(base, res, symbol) elif expo.is_irrational: root = Lambda(n, real_root(n, expo)) g_ys_pos = g_ys & Interval(0, oo) res = imageset(root, g_ys_pos) return _invert_real(base, res, symbol) else: # indeterminate exponent, e.g. Float or parity of # num, den of rational could not be determined pass # use default return if not base_has_sym: rhs = g_ys.args[0] if base.is_positive: return _invert_real(expo, imageset(Lambda(n, log(n, base, evaluate=False)), g_ys), symbol) elif base.is_negative: from sympy.core.power import integer_log s, b = integer_log(rhs, base) if b: return _invert_real(expo, FiniteSet(s), symbol) else: return _invert_real(expo, S.EmptySet, symbol) elif base.is_zero: one = Eq(rhs, 1) if one == S.true: # special case: 0**x - 1 return _invert_real(expo, FiniteSet(0), symbol) elif one == S.false: return _invert_real(expo, S.EmptySet, symbol) if isinstance(f, TrigonometricFunction): if isinstance(g_ys, FiniteSet): def inv(trig): if isinstance(f, (sin, csc)): F = asin if isinstance(f, sin) else acsc return (lambda a: n*pi + (-1)**n*F(a),) if isinstance(f, (cos, sec)): F = acos if isinstance(f, cos) else asec return ( lambda a: 2*n*pi + F(a), lambda a: 2*n*pi - F(a),) if isinstance(f, (tan, cot)): return (lambda a: n*pi + f.inverse()(a),) n = Dummy('n', integer=True) invs = S.EmptySet for L in inv(f): invs += Union(*[imageset(Lambda(n, L(g)), S.Integers) for g in g_ys]) return _invert_real(f.args[0], invs, symbol) return (f, g_ys) def _invert_complex(f, g_ys, symbol): """Helper function for _invert.""" if f == symbol: return (f, g_ys) n = Dummy('n') if f.is_Add: # f = g + h g, h = f.as_independent(symbol) if g is not S.Zero: return _invert_complex(h, imageset(Lambda(n, n - g), g_ys), symbol) if f.is_Mul: # f = g*h g, h = f.as_independent(symbol) if g is not S.One: if g in {S.NegativeInfinity, S.ComplexInfinity, S.Infinity}: return (h, S.EmptySet) return _invert_complex(h, imageset(Lambda(n, n/g), g_ys), symbol) if f.is_Pow: base, expo = f.args # special case: g**r = 0 # Could be improved like `_invert_real` to handle more general cases. if expo.is_Rational and g_ys == FiniteSet(0): if expo.is_positive: return _invert_complex(base, g_ys, symbol) if hasattr(f, 'inverse') and f.inverse() is not None and \ not isinstance(f, TrigonometricFunction) and \ not isinstance(f, HyperbolicFunction) and \ not isinstance(f, exp): if len(f.args) > 1: raise ValueError("Only functions with one argument are supported.") return _invert_complex(f.args[0], imageset(Lambda(n, f.inverse()(n)), g_ys), symbol) if isinstance(f, exp) or (f.is_Pow and f.base == S.Exp1): if isinstance(g_ys, ImageSet): # can solve upto `(d*exp(exp(...(exp(a*x + b))...) + c)` format. # Further can be improved to `(d*exp(exp(...(exp(a*x**n + b*x**(n-1) + ... + f))...) + c)`. g_ys_expr = g_ys.lamda.expr g_ys_vars = g_ys.lamda.variables k = Dummy('k{}'.format(len(g_ys_vars))) g_ys_vars_1 = (k,) + g_ys_vars exp_invs = Union(*[imageset(Lambda((g_ys_vars_1,), (I*(2*k*pi + arg(g_ys_expr)) + log(Abs(g_ys_expr)))), S.Integers**(len(g_ys_vars_1)))]) elif isinstance(g_ys, FiniteSet): exp_invs = Union(*[imageset(Lambda(n, I*(2*n*pi + arg(g_y)) + log(Abs(g_y))), S.Integers) for g_y in g_ys if g_y != 0]) return _invert_complex(f.exp, exp_invs, symbol) return (f, g_ys) def _invert_abs(f, g_ys, symbol): """Helper function for inverting absolute value functions. Returns the complete result of inverting an absolute value function along with the conditions which must also be satisfied. If it is certain that all these conditions are met, a `FiniteSet` of all possible solutions is returned. If any condition cannot be satisfied, an `EmptySet` is returned. Otherwise, a `ConditionSet` of the solutions, with all the required conditions specified, is returned. """ if not g_ys.is_FiniteSet: # this could be used for FiniteSet, but the # results are more compact if they aren't, e.g. # ConditionSet(x, Contains(n, Interval(0, oo)), {-n, n}) vs # Union(Intersection(Interval(0, oo), {n}), Intersection(Interval(-oo, 0), {-n})) # for the solution of abs(x) - n pos = Intersection(g_ys, Interval(0, S.Infinity)) parg = _invert_real(f, pos, symbol) narg = _invert_real(-f, pos, symbol) if parg[0] != narg[0]: raise NotImplementedError return parg[0], Union(narg[1], parg[1]) # check conditions: all these must be true. If any are unknown # then return them as conditions which must be satisfied unknown = [] for a in g_ys.args: ok = a.is_nonnegative if a.is_Number else a.is_positive if ok is None: unknown.append(a) elif not ok: return symbol, S.EmptySet if unknown: conditions = And(*[Contains(i, Interval(0, oo)) for i in unknown]) else: conditions = True n = Dummy('n', real=True) # this is slightly different than above: instead of solving # +/-f on positive values, here we solve for f on +/- g_ys g_x, values = _invert_real(f, Union( imageset(Lambda(n, n), g_ys), imageset(Lambda(n, -n), g_ys)), symbol) return g_x, ConditionSet(g_x, conditions, values) def domain_check(f, symbol, p): """Returns False if point p is infinite or any subexpression of f is infinite or becomes so after replacing symbol with p. If none of these conditions is met then True will be returned. Examples ======== >>> from sympy import Mul, oo >>> from sympy.abc import x >>> from sympy.solvers.solveset import domain_check >>> g = 1/(1 + (1/(x + 1))**2) >>> domain_check(g, x, -1) False >>> domain_check(x**2, x, 0) True >>> domain_check(1/x, x, oo) False * The function relies on the assumption that the original form of the equation has not been changed by automatic simplification. >>> domain_check(x/x, x, 0) # x/x is automatically simplified to 1 True * To deal with automatic evaluations use evaluate=False: >>> domain_check(Mul(x, 1/x, evaluate=False), x, 0) False """ f, p = sympify(f), sympify(p) if p.is_infinite: return False return _domain_check(f, symbol, p) def _domain_check(f, symbol, p): # helper for domain check if f.is_Atom and f.is_finite: return True elif f.subs(symbol, p).is_infinite: return False elif isinstance(f, Piecewise): # Check the cases of the Piecewise in turn. There might be invalid # expressions in later cases that don't apply e.g. # solveset(Piecewise((0, Eq(x, 0)), (1/x, True)), x) for expr, cond in f.args: condsubs = cond.subs(symbol, p) if condsubs is S.false: continue elif condsubs is S.true: return _domain_check(expr, symbol, p) else: # We don't know which case of the Piecewise holds. On this # basis we cannot decide whether any solution is in or out of # the domain. Ideally this function would allow returning a # symbolic condition for the validity of the solution that # could be handled in the calling code. In the mean time we'll # give this particular solution the benefit of the doubt and # let it pass. return True else: # TODO : We should not blindly recurse through all args of arbitrary expressions like this return all([_domain_check(g, symbol, p) for g in f.args]) def _is_finite_with_finite_vars(f, domain=S.Complexes): """ Return True if the given expression is finite. For symbols that don't assign a value for `complex` and/or `real`, the domain will be used to assign a value; symbols that don't assign a value for `finite` will be made finite. All other assumptions are left unmodified. """ def assumptions(s): A = s.assumptions0 A.setdefault('finite', A.get('finite', True)) if domain.is_subset(S.Reals): # if this gets set it will make complex=True, too A.setdefault('real', True) else: # don't change 'real' because being complex implies # nothing about being real A.setdefault('complex', True) return A reps = {s: Dummy(**assumptions(s)) for s in f.free_symbols} return f.xreplace(reps).is_finite def _is_function_class_equation(func_class, f, symbol): """ Tests whether the equation is an equation of the given function class. The given equation belongs to the given function class if it is comprised of functions of the function class which are multiplied by or added to expressions independent of the symbol. In addition, the arguments of all such functions must be linear in the symbol as well. Examples ======== >>> from sympy.solvers.solveset import _is_function_class_equation >>> from sympy import tan, sin, tanh, sinh, exp >>> from sympy.abc import x >>> from sympy.functions.elementary.trigonometric import (TrigonometricFunction, ... HyperbolicFunction) >>> _is_function_class_equation(TrigonometricFunction, exp(x) + tan(x), x) False >>> _is_function_class_equation(TrigonometricFunction, tan(x) + sin(x), x) True >>> _is_function_class_equation(TrigonometricFunction, tan(x**2), x) False >>> _is_function_class_equation(TrigonometricFunction, tan(x + 2), x) True >>> _is_function_class_equation(HyperbolicFunction, tanh(x) + sinh(x), x) True """ if f.is_Mul or f.is_Add: return all(_is_function_class_equation(func_class, arg, symbol) for arg in f.args) if f.is_Pow: if not f.exp.has(symbol): return _is_function_class_equation(func_class, f.base, symbol) else: return False if not f.has(symbol): return True if isinstance(f, func_class): try: g = Poly(f.args[0], symbol) return g.degree() <= 1 except PolynomialError: return False else: return False def _solve_as_rational(f, symbol, domain): """ solve rational functions""" from sympy.core.function import _mexpand f = together(_mexpand(f, recursive=True), deep=True) g, h = fraction(f) if not h.has(symbol): try: return _solve_as_poly(g, symbol, domain) except NotImplementedError: # The polynomial formed from g could end up having # coefficients in a ring over which finding roots # isn't implemented yet, e.g. ZZ[a] for some symbol a return ConditionSet(symbol, Eq(f, 0), domain) except CoercionFailed: # contained oo, zoo or nan return S.EmptySet else: valid_solns = _solveset(g, symbol, domain) invalid_solns = _solveset(h, symbol, domain) return valid_solns - invalid_solns class _SolveTrig1Error(Exception): """Raised when _solve_trig1 heuristics do not apply""" def _solve_trig(f, symbol, domain): """Function to call other helpers to solve trigonometric equations """ sol = None try: sol = _solve_trig1(f, symbol, domain) except _SolveTrig1Error: try: sol = _solve_trig2(f, symbol, domain) except ValueError: raise NotImplementedError(filldedent(''' Solution to this kind of trigonometric equations is yet to be implemented''')) return sol def _solve_trig1(f, symbol, domain): """Primary solver for trigonometric and hyperbolic equations Returns either the solution set as a ConditionSet (auto-evaluated to a union of ImageSets if no variables besides 'symbol' are involved) or raises _SolveTrig1Error if f == 0 can't be solved. Notes ===== Algorithm: 1. Do a change of variable x -> mu*x in arguments to trigonometric and hyperbolic functions, in order to reduce them to small integers. (This step is crucial to keep the degrees of the polynomials of step 4 low.) 2. Rewrite trigonometric/hyperbolic functions as exponentials. 3. Proceed to a 2nd change of variable, replacing exp(I*x) or exp(x) by y. 4. Solve the resulting rational equation. 5. Use invert_complex or invert_real to return to the original variable. 6. If the coefficients of 'symbol' were symbolic in nature, add the necessary consistency conditions in a ConditionSet. """ # Prepare change of variable x = Dummy('x') if _is_function_class_equation(HyperbolicFunction, f, symbol): cov = exp(x) inverter = invert_real if domain.is_subset(S.Reals) else invert_complex else: cov = exp(I*x) inverter = invert_complex f = trigsimp(f) f_original = f trig_functions = f.atoms(TrigonometricFunction, HyperbolicFunction) trig_arguments = [e.args[0] for e in trig_functions] # trigsimp may have reduced the equation to an expression # that is independent of 'symbol' (e.g. cos**2+sin**2) if not any(a.has(symbol) for a in trig_arguments): return solveset(f_original, symbol, domain) denominators = [] numerators = [] for ar in trig_arguments: try: poly_ar = Poly(ar, symbol) except PolynomialError: raise _SolveTrig1Error("trig argument is not a polynomial") if poly_ar.degree() > 1: # degree >1 still bad raise _SolveTrig1Error("degree of variable must not exceed one") if poly_ar.degree() == 0: # degree 0, don't care continue c = poly_ar.all_coeffs()[0] # got the coefficient of 'symbol' numerators.append(fraction(c)[0]) denominators.append(fraction(c)[1]) mu = lcm(denominators)/gcd(numerators) f = f.subs(symbol, mu*x) f = f.rewrite(exp) f = together(f) g, h = fraction(f) y = Dummy('y') g, h = g.expand(), h.expand() g, h = g.subs(cov, y), h.subs(cov, y) if g.has(x) or h.has(x): raise _SolveTrig1Error("change of variable not possible") solns = solveset_complex(g, y) - solveset_complex(h, y) if isinstance(solns, ConditionSet): raise _SolveTrig1Error("polynomial has ConditionSet solution") if isinstance(solns, FiniteSet): if any(isinstance(s, RootOf) for s in solns): raise _SolveTrig1Error("polynomial results in RootOf object") # revert the change of variable cov = cov.subs(x, symbol/mu) result = Union(*[inverter(cov, s, symbol)[1] for s in solns]) # In case of symbolic coefficients, the solution set is only valid # if numerator and denominator of mu are non-zero. if mu.has(Symbol): syms = (mu).atoms(Symbol) munum, muden = fraction(mu) condnum = munum.as_independent(*syms, as_Add=False)[1] condden = muden.as_independent(*syms, as_Add=False)[1] cond = And(Ne(condnum, 0), Ne(condden, 0)) else: cond = True # Actual conditions are returned as part of the ConditionSet. Adding an # intersection with C would only complicate some solution sets due to # current limitations of intersection code. (e.g. #19154) if domain is S.Complexes: # This is a slight abuse of ConditionSet. Ideally this should # be some kind of "PiecewiseSet". (See #19507 discussion) return ConditionSet(symbol, cond, result) else: return ConditionSet(symbol, cond, Intersection(result, domain)) elif solns is S.EmptySet: return S.EmptySet else: raise _SolveTrig1Error("polynomial solutions must form FiniteSet") def _solve_trig2(f, symbol, domain): """Secondary helper to solve trigonometric equations, called when first helper fails """ from sympy import ilcm, expand_trig, degree f = trigsimp(f) f_original = f trig_functions = f.atoms(sin, cos, tan, sec, cot, csc) trig_arguments = [e.args[0] for e in trig_functions] denominators = [] numerators = [] # todo: This solver can be extended to hyperbolics if the # analogous change of variable to tanh (instead of tan) # is used. if not trig_functions: return ConditionSet(symbol, Eq(f_original, 0), domain) # todo: The pre-processing below (extraction of numerators, denominators, # gcd, lcm, mu, etc.) should be updated to the enhanced version in # _solve_trig1. (See #19507) for ar in trig_arguments: try: poly_ar = Poly(ar, symbol) except PolynomialError: raise ValueError("give up, we can't solve if this is not a polynomial in x") if poly_ar.degree() > 1: # degree >1 still bad raise ValueError("degree of variable inside polynomial should not exceed one") if poly_ar.degree() == 0: # degree 0, don't care continue c = poly_ar.all_coeffs()[0] # got the coefficient of 'symbol' try: numerators.append(Rational(c).p) denominators.append(Rational(c).q) except TypeError: return ConditionSet(symbol, Eq(f_original, 0), domain) x = Dummy('x') # ilcm() and igcd() require more than one argument if len(numerators) > 1: mu = Rational(2)*ilcm(*denominators)/igcd(*numerators) else: assert len(numerators) == 1 mu = Rational(2)*denominators[0]/numerators[0] f = f.subs(symbol, mu*x) f = f.rewrite(tan) f = expand_trig(f) f = together(f) g, h = fraction(f) y = Dummy('y') g, h = g.expand(), h.expand() g, h = g.subs(tan(x), y), h.subs(tan(x), y) if g.has(x) or h.has(x): return ConditionSet(symbol, Eq(f_original, 0), domain) solns = solveset(g, y, S.Reals) - solveset(h, y, S.Reals) if isinstance(solns, FiniteSet): result = Union(*[invert_real(tan(symbol/mu), s, symbol)[1] for s in solns]) dsol = invert_real(tan(symbol/mu), oo, symbol)[1] if degree(h) > degree(g): # If degree(denom)>degree(num) then there result = Union(result, dsol) # would be another sol at Lim(denom-->oo) return Intersection(result, domain) elif solns is S.EmptySet: return S.EmptySet else: return ConditionSet(symbol, Eq(f_original, 0), S.Reals) def _solve_as_poly(f, symbol, domain=S.Complexes): """ Solve the equation using polynomial techniques if it already is a polynomial equation or, with a change of variables, can be made so. """ result = None if f.is_polynomial(symbol): solns = roots(f, symbol, cubics=True, quartics=True, quintics=True, domain='EX') num_roots = sum(solns.values()) if degree(f, symbol) <= num_roots: result = FiniteSet(*solns.keys()) else: poly = Poly(f, symbol) solns = poly.all_roots() if poly.degree() <= len(solns): result = FiniteSet(*solns) else: result = ConditionSet(symbol, Eq(f, 0), domain) else: poly = Poly(f) if poly is None: result = ConditionSet(symbol, Eq(f, 0), domain) gens = [g for g in poly.gens if g.has(symbol)] if len(gens) == 1: poly = Poly(poly, gens[0]) gen = poly.gen deg = poly.degree() poly = Poly(poly.as_expr(), poly.gen, composite=True) poly_solns = FiniteSet(*roots(poly, cubics=True, quartics=True, quintics=True).keys()) if len(poly_solns) < deg: result = ConditionSet(symbol, Eq(f, 0), domain) if gen != symbol: y = Dummy('y') inverter = invert_real if domain.is_subset(S.Reals) else invert_complex lhs, rhs_s = inverter(gen, y, symbol) if lhs == symbol: result = Union(*[rhs_s.subs(y, s) for s in poly_solns]) else: result = ConditionSet(symbol, Eq(f, 0), domain) else: result = ConditionSet(symbol, Eq(f, 0), domain) if result is not None: if isinstance(result, FiniteSet): # this is to simplify solutions like -sqrt(-I) to sqrt(2)/2 # - sqrt(2)*I/2. We are not expanding for solution with symbols # or undefined functions because that makes the solution more complicated. # For example, expand_complex(a) returns re(a) + I*im(a) if all([s.atoms(Symbol, AppliedUndef) == set() and not isinstance(s, RootOf) for s in result]): s = Dummy('s') result = imageset(Lambda(s, expand_complex(s)), result) if isinstance(result, FiniteSet) and domain != S.Complexes: # Avoid adding gratuitous intersections with S.Complexes. Actual # conditions should be handled elsewhere. result = result.intersection(domain) return result else: return ConditionSet(symbol, Eq(f, 0), domain) def _solve_radical(f, unradf, symbol, solveset_solver): """ Helper function to solve equations with radicals """ res = unradf eq, cov = res if res else (f, []) if not cov: result = solveset_solver(eq, symbol) - \ Union(*[solveset_solver(g, symbol) for g in denoms(f, symbol)]) else: y, yeq = cov if not solveset_solver(y - I, y): yreal = Dummy('yreal', real=True) yeq = yeq.xreplace({y: yreal}) eq = eq.xreplace({y: yreal}) y = yreal g_y_s = solveset_solver(yeq, symbol) f_y_sols = solveset_solver(eq, y) result = Union(*[imageset(Lambda(y, g_y), f_y_sols) for g_y in g_y_s]) if isinstance(result, Complement) or isinstance(result,ConditionSet): solution_set = result else: f_set = [] # solutions for FiniteSet c_set = [] # solutions for ConditionSet for s in result: if checksol(f, symbol, s): f_set.append(s) else: c_set.append(s) solution_set = FiniteSet(*f_set) + ConditionSet(symbol, Eq(f, 0), FiniteSet(*c_set)) return solution_set def _solve_abs(f, symbol, domain): """ Helper function to solve equation involving absolute value function """ if not domain.is_subset(S.Reals): raise ValueError(filldedent(''' Absolute values cannot be inverted in the complex domain.''')) p, q, r = Wild('p'), Wild('q'), Wild('r') pattern_match = f.match(p*Abs(q) + r) or {} f_p, f_q, f_r = [pattern_match.get(i, S.Zero) for i in (p, q, r)] if not (f_p.is_zero or f_q.is_zero): domain = continuous_domain(f_q, symbol, domain) q_pos_cond = solve_univariate_inequality(f_q >= 0, symbol, relational=False, domain=domain, continuous=True) q_neg_cond = q_pos_cond.complement(domain) sols_q_pos = solveset_real(f_p*f_q + f_r, symbol).intersect(q_pos_cond) sols_q_neg = solveset_real(f_p*(-f_q) + f_r, symbol).intersect(q_neg_cond) return Union(sols_q_pos, sols_q_neg) else: return ConditionSet(symbol, Eq(f, 0), domain) def solve_decomposition(f, symbol, domain): """ Function to solve equations via the principle of "Decomposition and Rewriting". Examples ======== >>> from sympy import exp, sin, Symbol, pprint, S >>> from sympy.solvers.solveset import solve_decomposition as sd >>> x = Symbol('x') >>> f1 = exp(2*x) - 3*exp(x) + 2 >>> sd(f1, x, S.Reals) FiniteSet(0, log(2)) >>> f2 = sin(x)**2 + 2*sin(x) + 1 >>> pprint(sd(f2, x, S.Reals), use_unicode=False) 3*pi {2*n*pi + ---- | n in Integers} 2 >>> f3 = sin(x + 2) >>> pprint(sd(f3, x, S.Reals), use_unicode=False) {2*n*pi - 2 | n in Integers} U {2*n*pi - 2 + pi | n in Integers} """ from sympy.solvers.decompogen import decompogen from sympy.calculus.util import function_range # decompose the given function g_s = decompogen(f, symbol) # `y_s` represents the set of values for which the function `g` is to be # solved. # `solutions` represent the solutions of the equations `g = y_s` or # `g = 0` depending on the type of `y_s`. # As we are interested in solving the equation: f = 0 y_s = FiniteSet(0) for g in g_s: frange = function_range(g, symbol, domain) y_s = Intersection(frange, y_s) result = S.EmptySet if isinstance(y_s, FiniteSet): for y in y_s: solutions = solveset(Eq(g, y), symbol, domain) if not isinstance(solutions, ConditionSet): result += solutions else: if isinstance(y_s, ImageSet): iter_iset = (y_s,) elif isinstance(y_s, Union): iter_iset = y_s.args elif y_s is EmptySet: # y_s is not in the range of g in g_s, so no solution exists #in the given domain return EmptySet for iset in iter_iset: new_solutions = solveset(Eq(iset.lamda.expr, g), symbol, domain) dummy_var = tuple(iset.lamda.expr.free_symbols)[0] (base_set,) = iset.base_sets if isinstance(new_solutions, FiniteSet): new_exprs = new_solutions elif isinstance(new_solutions, Intersection): if isinstance(new_solutions.args[1], FiniteSet): new_exprs = new_solutions.args[1] for new_expr in new_exprs: result += ImageSet(Lambda(dummy_var, new_expr), base_set) if result is S.EmptySet: return ConditionSet(symbol, Eq(f, 0), domain) y_s = result return y_s def _solveset(f, symbol, domain, _check=False): """Helper for solveset to return a result from an expression that has already been sympify'ed and is known to contain the given symbol.""" # _check controls whether the answer is checked or not from sympy.simplify.simplify import signsimp from sympy.logic.boolalg import BooleanTrue if isinstance(f, BooleanTrue): return domain orig_f = f if f.is_Mul: coeff, f = f.as_independent(symbol, as_Add=False) if coeff in {S.ComplexInfinity, S.NegativeInfinity, S.Infinity}: f = together(orig_f) elif f.is_Add: a, h = f.as_independent(symbol) m, h = h.as_independent(symbol, as_Add=False) if m not in {S.ComplexInfinity, S.Zero, S.Infinity, S.NegativeInfinity}: f = a/m + h # XXX condition `m != 0` should be added to soln # assign the solvers to use solver = lambda f, x, domain=domain: _solveset(f, x, domain) inverter = lambda f, rhs, symbol: _invert(f, rhs, symbol, domain) result = EmptySet if f.expand().is_zero: return domain elif not f.has(symbol): return EmptySet elif f.is_Mul and all(_is_finite_with_finite_vars(m, domain) for m in f.args): # if f(x) and g(x) are both finite we can say that the solution of # f(x)*g(x) == 0 is same as Union(f(x) == 0, g(x) == 0) is not true in # general. g(x) can grow to infinitely large for the values where # f(x) == 0. To be sure that we are not silently allowing any # wrong solutions we are using this technique only if both f and g are # finite for a finite input. result = Union(*[solver(m, symbol) for m in f.args]) elif _is_function_class_equation(TrigonometricFunction, f, symbol) or \ _is_function_class_equation(HyperbolicFunction, f, symbol): result = _solve_trig(f, symbol, domain) elif isinstance(f, arg): a = f.args[0] result = solveset_real(a > 0, symbol) elif f.is_Piecewise: expr_set_pairs = f.as_expr_set_pairs(domain) for (expr, in_set) in expr_set_pairs: if in_set.is_Relational: in_set = in_set.as_set() solns = solver(expr, symbol, in_set) result += solns elif isinstance(f, Eq): result = solver(Add(f.lhs, - f.rhs, evaluate=False), symbol, domain) elif f.is_Relational: try: result = solve_univariate_inequality( f, symbol, domain=domain, relational=False) except NotImplementedError: result = ConditionSet(symbol, f, domain) return result elif _is_modular(f, symbol): result = _solve_modular(f, symbol, domain) else: lhs, rhs_s = inverter(f, 0, symbol) if lhs == symbol: # do some very minimal simplification since # repeated inversion may have left the result # in a state that other solvers (e.g. poly) # would have simplified; this is done here # rather than in the inverter since here it # is only done once whereas there it would # be repeated for each step of the inversion if isinstance(rhs_s, FiniteSet): rhs_s = FiniteSet(*[Mul(* signsimp(i).as_content_primitive()) for i in rhs_s]) result = rhs_s elif isinstance(rhs_s, FiniteSet): for equation in [lhs - rhs for rhs in rhs_s]: if equation == f: u = unrad(f) if u: result += _solve_radical(equation, u, symbol, solver) elif equation.has(Abs): result += _solve_abs(f, symbol, domain) else: result_rational = _solve_as_rational(equation, symbol, domain) if not isinstance(result_rational, ConditionSet): result += result_rational else: # may be a transcendental type equation t_result = _transolve(equation, symbol, domain) if isinstance(t_result, ConditionSet): # might need factoring; this is expensive so we # have delayed until now. To avoid recursion # errors look for a non-trivial factoring into # a product of symbol dependent terms; I think # that something that factors as a Pow would # have already been recognized by now. factored = equation.factor() if factored.is_Mul and equation != factored: _, dep = factored.as_independent(symbol) if not dep.is_Add: # non-trivial factoring of equation # but use form with constants # in case they need special handling t_result = solver(factored, symbol) result += t_result else: result += solver(equation, symbol) elif rhs_s is not S.EmptySet: result = ConditionSet(symbol, Eq(f, 0), domain) if isinstance(result, ConditionSet): if isinstance(f, Expr): num, den = f.as_numer_denom() else: num, den = f, S.One if den.has(symbol): _result = _solveset(num, symbol, domain) if not isinstance(_result, ConditionSet): singularities = _solveset(den, symbol, domain) result = _result - singularities if _check: if isinstance(result, ConditionSet): # it wasn't solved or has enumerated all conditions # -- leave it alone return result # whittle away all but the symbol-containing core # to use this for testing if isinstance(orig_f, Expr): fx = orig_f.as_independent(symbol, as_Add=True)[1] fx = fx.as_independent(symbol, as_Add=False)[1] else: fx = orig_f if isinstance(result, FiniteSet): # check the result for invalid solutions result = FiniteSet(*[s for s in result if isinstance(s, RootOf) or domain_check(fx, symbol, s)]) return result def _is_modular(f, symbol): """ Helper function to check below mentioned types of modular equations. ``A - Mod(B, C) = 0`` A -> This can or cannot be a function of symbol. B -> This is surely a function of symbol. C -> It is an integer. Parameters ========== f : Expr The equation to be checked. symbol : Symbol The concerned variable for which the equation is to be checked. Examples ======== >>> from sympy import symbols, exp, Mod >>> from sympy.solvers.solveset import _is_modular as check >>> x, y = symbols('x y') >>> check(Mod(x, 3) - 1, x) True >>> check(Mod(x, 3) - 1, y) False >>> check(Mod(x, 3)**2 - 5, x) False >>> check(Mod(x, 3)**2 - y, x) False >>> check(exp(Mod(x, 3)) - 1, x) False >>> check(Mod(3, y) - 1, y) False """ if not f.has(Mod): return False # extract modterms from f. modterms = list(f.atoms(Mod)) return (len(modterms) == 1 and # only one Mod should be present modterms[0].args[0].has(symbol) and # B-> function of symbol modterms[0].args[1].is_integer and # C-> to be an integer. any(isinstance(term, Mod) for term in list(_term_factors(f))) # free from other funcs ) def _invert_modular(modterm, rhs, n, symbol): """ Helper function to invert modular equation. ``Mod(a, m) - rhs = 0`` Generally it is inverted as (a, ImageSet(Lambda(n, m*n + rhs), S.Integers)). More simplified form will be returned if possible. If it is not invertible then (modterm, rhs) is returned. The following cases arise while inverting equation ``Mod(a, m) - rhs = 0``: 1. If a is symbol then m*n + rhs is the required solution. 2. If a is an instance of ``Add`` then we try to find two symbol independent parts of a and the symbol independent part gets tranferred to the other side and again the ``_invert_modular`` is called on the symbol dependent part. 3. If a is an instance of ``Mul`` then same as we done in ``Add`` we separate out the symbol dependent and symbol independent parts and transfer the symbol independent part to the rhs with the help of invert and again the ``_invert_modular`` is called on the symbol dependent part. 4. If a is an instance of ``Pow`` then two cases arise as following: - If a is of type (symbol_indep)**(symbol_dep) then the remainder is evaluated with the help of discrete_log function and then the least period is being found out with the help of totient function. period*n + remainder is the required solution in this case. For reference: (https://en.wikipedia.org/wiki/Euler's_theorem) - If a is of type (symbol_dep)**(symbol_indep) then we try to find all primitive solutions list with the help of nthroot_mod function. m*n + rem is the general solution where rem belongs to solutions list from nthroot_mod function. Parameters ========== modterm, rhs : Expr The modular equation to be inverted, ``modterm - rhs = 0`` symbol : Symbol The variable in the equation to be inverted. n : Dummy Dummy variable for output g_n. Returns ======= A tuple (f_x, g_n) is being returned where f_x is modular independent function of symbol and g_n being set of values f_x can have. Examples ======== >>> from sympy import symbols, exp, Mod, Dummy, S >>> from sympy.solvers.solveset import _invert_modular as invert_modular >>> x, y = symbols('x y') >>> n = Dummy('n') >>> invert_modular(Mod(exp(x), 7), S(5), n, x) (Mod(exp(x), 7), 5) >>> invert_modular(Mod(x, 7), S(5), n, x) (x, ImageSet(Lambda(_n, 7*_n + 5), Integers)) >>> invert_modular(Mod(3*x + 8, 7), S(5), n, x) (x, ImageSet(Lambda(_n, 7*_n + 6), Integers)) >>> invert_modular(Mod(x**4, 7), S(5), n, x) (x, EmptySet) >>> invert_modular(Mod(2**(x**2 + x + 1), 7), S(2), n, x) (x**2 + x + 1, ImageSet(Lambda(_n, 3*_n + 1), Naturals0)) """ a, m = modterm.args if rhs.is_real is False or any(term.is_real is False for term in list(_term_factors(a))): # Check for complex arguments return modterm, rhs if abs(rhs) >= abs(m): # if rhs has value greater than value of m. return symbol, EmptySet if a == symbol: return symbol, ImageSet(Lambda(n, m*n + rhs), S.Integers) if a.is_Add: # g + h = a g, h = a.as_independent(symbol) if g is not S.Zero: x_indep_term = rhs - Mod(g, m) return _invert_modular(Mod(h, m), Mod(x_indep_term, m), n, symbol) if a.is_Mul: # g*h = a g, h = a.as_independent(symbol) if g is not S.One: x_indep_term = rhs*invert(g, m) return _invert_modular(Mod(h, m), Mod(x_indep_term, m), n, symbol) if a.is_Pow: # base**expo = a base, expo = a.args if expo.has(symbol) and not base.has(symbol): # remainder -> solution independent of n of equation. # m, rhs are made coprime by dividing igcd(m, rhs) try: remainder = discrete_log(m / igcd(m, rhs), rhs, a.base) except ValueError: # log does not exist return modterm, rhs # period -> coefficient of n in the solution and also referred as # the least period of expo in which it is repeats itself. # (a**(totient(m)) - 1) divides m. Here is link of theorem: # (https://en.wikipedia.org/wiki/Euler's_theorem) period = totient(m) for p in divisors(period): # there might a lesser period exist than totient(m). if pow(a.base, p, m / igcd(m, a.base)) == 1: period = p break # recursion is not applied here since _invert_modular is currently # not smart enough to handle infinite rhs as here expo has infinite # rhs = ImageSet(Lambda(n, period*n + remainder), S.Naturals0). return expo, ImageSet(Lambda(n, period*n + remainder), S.Naturals0) elif base.has(symbol) and not expo.has(symbol): try: remainder_list = nthroot_mod(rhs, expo, m, all_roots=True) if remainder_list == []: return symbol, EmptySet except (ValueError, NotImplementedError): return modterm, rhs g_n = EmptySet for rem in remainder_list: g_n += ImageSet(Lambda(n, m*n + rem), S.Integers) return base, g_n return modterm, rhs def _solve_modular(f, symbol, domain): r""" Helper function for solving modular equations of type ``A - Mod(B, C) = 0``, where A can or cannot be a function of symbol, B is surely a function of symbol and C is an integer. Currently ``_solve_modular`` is only able to solve cases where A is not a function of symbol. Parameters ========== f : Expr The modular equation to be solved, ``f = 0`` symbol : Symbol The variable in the equation to be solved. domain : Set A set over which the equation is solved. It has to be a subset of Integers. Returns ======= A set of integer solutions satisfying the given modular equation. A ``ConditionSet`` if the equation is unsolvable. Examples ======== >>> from sympy.solvers.solveset import _solve_modular as solve_modulo >>> from sympy import S, Symbol, sin, Intersection, Interval >>> from sympy.core.mod import Mod >>> x = Symbol('x') >>> solve_modulo(Mod(5*x - 8, 7) - 3, x, S.Integers) ImageSet(Lambda(_n, 7*_n + 5), Integers) >>> solve_modulo(Mod(5*x - 8, 7) - 3, x, S.Reals) # domain should be subset of integers. ConditionSet(x, Eq(Mod(5*x + 6, 7) - 3, 0), Reals) >>> solve_modulo(-7 + Mod(x, 5), x, S.Integers) EmptySet >>> solve_modulo(Mod(12**x, 21) - 18, x, S.Integers) ImageSet(Lambda(_n, 6*_n + 2), Naturals0) >>> solve_modulo(Mod(sin(x), 7) - 3, x, S.Integers) # not solvable ConditionSet(x, Eq(Mod(sin(x), 7) - 3, 0), Integers) >>> solve_modulo(3 - Mod(x, 5), x, Intersection(S.Integers, Interval(0, 100))) Intersection(ImageSet(Lambda(_n, 5*_n + 3), Integers), Range(0, 101, 1)) """ # extract modterm and g_y from f unsolved_result = ConditionSet(symbol, Eq(f, 0), domain) modterm = list(f.atoms(Mod))[0] rhs = -S.One*(f.subs(modterm, S.Zero)) if f.as_coefficients_dict()[modterm].is_negative: # checks if coefficient of modterm is negative in main equation. rhs *= -S.One if not domain.is_subset(S.Integers): return unsolved_result if rhs.has(symbol): # TODO Case: A-> function of symbol, can be extended here # in future. return unsolved_result n = Dummy('n', integer=True) f_x, g_n = _invert_modular(modterm, rhs, n, symbol) if f_x == modterm and g_n == rhs: return unsolved_result if f_x == symbol: if domain is not S.Integers: return domain.intersect(g_n) return g_n if isinstance(g_n, ImageSet): lamda_expr = g_n.lamda.expr lamda_vars = g_n.lamda.variables base_sets = g_n.base_sets sol_set = _solveset(f_x - lamda_expr, symbol, S.Integers) if isinstance(sol_set, FiniteSet): tmp_sol = EmptySet for sol in sol_set: tmp_sol += ImageSet(Lambda(lamda_vars, sol), *base_sets) sol_set = tmp_sol else: sol_set = ImageSet(Lambda(lamda_vars, sol_set), *base_sets) return domain.intersect(sol_set) return unsolved_result def _term_factors(f): """ Iterator to get the factors of all terms present in the given equation. Parameters ========== f : Expr Equation that needs to be addressed Returns ======= Factors of all terms present in the equation. Examples ======== >>> from sympy import symbols >>> from sympy.solvers.solveset import _term_factors >>> x = symbols('x') >>> list(_term_factors(-2 - x**2 + x*(x + 1))) [-2, -1, x**2, x, x + 1] """ for add_arg in Add.make_args(f): yield from Mul.make_args(add_arg) def _solve_exponential(lhs, rhs, symbol, domain): r""" Helper function for solving (supported) exponential equations. Exponential equations are the sum of (currently) at most two terms with one or both of them having a power with a symbol-dependent exponent. For example .. math:: 5^{2x + 3} - 5^{3x - 1} .. math:: 4^{5 - 9x} - e^{2 - x} Parameters ========== lhs, rhs : Expr The exponential equation to be solved, `lhs = rhs` symbol : Symbol The variable in which the equation is solved domain : Set A set over which the equation is solved. Returns ======= A set of solutions satisfying the given equation. A ``ConditionSet`` if the equation is unsolvable or if the assumptions are not properly defined, in that case a different style of ``ConditionSet`` is returned having the solution(s) of the equation with the desired assumptions. Examples ======== >>> from sympy.solvers.solveset import _solve_exponential as solve_expo >>> from sympy import symbols, S >>> x = symbols('x', real=True) >>> a, b = symbols('a b') >>> solve_expo(2**x + 3**x - 5**x, 0, x, S.Reals) # not solvable ConditionSet(x, Eq(2**x + 3**x - 5**x, 0), Reals) >>> solve_expo(a**x - b**x, 0, x, S.Reals) # solvable but incorrect assumptions ConditionSet(x, (a > 0) & (b > 0), FiniteSet(0)) >>> solve_expo(3**(2*x) - 2**(x + 3), 0, x, S.Reals) FiniteSet(-3*log(2)/(-2*log(3) + log(2))) >>> solve_expo(2**x - 4**x, 0, x, S.Reals) FiniteSet(0) * Proof of correctness of the method The logarithm function is the inverse of the exponential function. The defining relation between exponentiation and logarithm is: .. math:: {\log_b x} = y \enspace if \enspace b^y = x Therefore if we are given an equation with exponent terms, we can convert every term to its corresponding logarithmic form. This is achieved by taking logarithms and expanding the equation using logarithmic identities so that it can easily be handled by ``solveset``. For example: .. math:: 3^{2x} = 2^{x + 3} Taking log both sides will reduce the equation to .. math:: (2x)\log(3) = (x + 3)\log(2) This form can be easily handed by ``solveset``. """ unsolved_result = ConditionSet(symbol, Eq(lhs - rhs, 0), domain) newlhs = powdenest(lhs) if lhs != newlhs: # it may also be advantageous to factor the new expr neweq = factor(newlhs - rhs) if neweq != (lhs - rhs): return _solveset(neweq, symbol, domain) # try again with _solveset if not (isinstance(lhs, Add) and len(lhs.args) == 2): # solving for the sum of more than two powers is possible # but not yet implemented return unsolved_result if rhs != 0: return unsolved_result a, b = list(ordered(lhs.args)) a_term = a.as_independent(symbol)[1] b_term = b.as_independent(symbol)[1] a_base, a_exp = a_term.as_base_exp() b_base, b_exp = b_term.as_base_exp() from sympy.functions.elementary.complexes import im if domain.is_subset(S.Reals): conditions = And( a_base > 0, b_base > 0, Eq(im(a_exp), 0), Eq(im(b_exp), 0)) else: conditions = And( Ne(a_base, 0), Ne(b_base, 0)) L, R = map(lambda i: expand_log(log(i), force=True), (a, -b)) solutions = _solveset(L - R, symbol, domain) return ConditionSet(symbol, conditions, solutions) def _is_exponential(f, symbol): r""" Return ``True`` if one or more terms contain ``symbol`` only in exponents, else ``False``. Parameters ========== f : Expr The equation to be checked symbol : Symbol The variable in which the equation is checked Examples ======== >>> from sympy import symbols, cos, exp >>> from sympy.solvers.solveset import _is_exponential as check >>> x, y = symbols('x y') >>> check(y, y) False >>> check(x**y - 1, y) True >>> check(x**y*2**y - 1, y) True >>> check(exp(x + 3) + 3**x, x) True >>> check(cos(2**x), x) False * Philosophy behind the helper The function extracts each term of the equation and checks if it is of exponential form w.r.t ``symbol``. """ rv = False for expr_arg in _term_factors(f): if symbol not in expr_arg.free_symbols: continue if (isinstance(expr_arg, Pow) and symbol not in expr_arg.base.free_symbols or isinstance(expr_arg, exp)): rv = True # symbol in exponent else: return False # dependent on symbol in non-exponential way return rv def _solve_logarithm(lhs, rhs, symbol, domain): r""" Helper to solve logarithmic equations which are reducible to a single instance of `\log`. Logarithmic equations are (currently) the equations that contains `\log` terms which can be reduced to a single `\log` term or a constant using various logarithmic identities. For example: .. math:: \log(x) + \log(x - 4) can be reduced to: .. math:: \log(x(x - 4)) Parameters ========== lhs, rhs : Expr The logarithmic equation to be solved, `lhs = rhs` symbol : Symbol The variable in which the equation is solved domain : Set A set over which the equation is solved. Returns ======= A set of solutions satisfying the given equation. A ``ConditionSet`` if the equation is unsolvable. Examples ======== >>> from sympy import symbols, log, S >>> from sympy.solvers.solveset import _solve_logarithm as solve_log >>> x = symbols('x') >>> f = log(x - 3) + log(x + 3) >>> solve_log(f, 0, x, S.Reals) FiniteSet(sqrt(10), -sqrt(10)) * Proof of correctness A logarithm is another way to write exponent and is defined by .. math:: {\log_b x} = y \enspace if \enspace b^y = x When one side of the equation contains a single logarithm, the equation can be solved by rewriting the equation as an equivalent exponential equation as defined above. But if one side contains more than one logarithm, we need to use the properties of logarithm to condense it into a single logarithm. Take for example .. math:: \log(2x) - 15 = 0 contains single logarithm, therefore we can directly rewrite it to exponential form as .. math:: x = \frac{e^{15}}{2} But if the equation has more than one logarithm as .. math:: \log(x - 3) + \log(x + 3) = 0 we use logarithmic identities to convert it into a reduced form Using, .. math:: \log(a) + \log(b) = \log(ab) the equation becomes, .. math:: \log((x - 3)(x + 3)) This equation contains one logarithm and can be solved by rewriting to exponents. """ new_lhs = logcombine(lhs, force=True) new_f = new_lhs - rhs return _solveset(new_f, symbol, domain) def _is_logarithmic(f, symbol): r""" Return ``True`` if the equation is in the form `a\log(f(x)) + b\log(g(x)) + ... + c` else ``False``. Parameters ========== f : Expr The equation to be checked symbol : Symbol The variable in which the equation is checked Returns ======= ``True`` if the equation is logarithmic otherwise ``False``. Examples ======== >>> from sympy import symbols, tan, log >>> from sympy.solvers.solveset import _is_logarithmic as check >>> x, y = symbols('x y') >>> check(log(x + 2) - log(x + 3), x) True >>> check(tan(log(2*x)), x) False >>> check(x*log(x), x) False >>> check(x + log(x), x) False >>> check(y + log(x), x) True * Philosophy behind the helper The function extracts each term and checks whether it is logarithmic w.r.t ``symbol``. """ rv = False for term in Add.make_args(f): saw_log = False for term_arg in Mul.make_args(term): if symbol not in term_arg.free_symbols: continue if isinstance(term_arg, log): if saw_log: return False # more than one log in term saw_log = True else: return False # dependent on symbol in non-log way if saw_log: rv = True return rv def _is_lambert(f, symbol): r""" If this returns ``False`` then the Lambert solver (``_solve_lambert``) will not be called. Explanation =========== Quick check for cases that the Lambert solver might be able to handle. 1. Equations containing more than two operands and `symbol`s involving any of `Pow`, `exp`, `HyperbolicFunction`,`TrigonometricFunction`, `log` terms. 2. In `Pow`, `exp` the exponent should have `symbol` whereas for `HyperbolicFunction`,`TrigonometricFunction`, `log` should contain `symbol`. 3. For `HyperbolicFunction`,`TrigonometricFunction` the number of trigonometric functions in equation should be less than number of symbols. (since `A*cos(x) + B*sin(x) - c` is not the Lambert type). Some forms of lambert equations are: 1. X**X = C 2. X*(B*log(X) + D)**A = C 3. A*log(B*X + A) + d*X = C 4. (B*X + A)*exp(d*X + g) = C 5. g*exp(B*X + h) - B*X = C 6. A*D**(E*X + g) - B*X = C 7. A*cos(X) + B*sin(X) - D*X = C 8. A*cosh(X) + B*sinh(X) - D*X = C Where X is any variable, A, B, C, D, E are any constants, g, h are linear functions or log terms. Parameters ========== f : Expr The equation to be checked symbol : Symbol The variable in which the equation is checked Returns ======= If this returns ``False`` then the Lambert solver (``_solve_lambert``) will not be called. Examples ======== >>> from sympy.solvers.solveset import _is_lambert >>> from sympy import symbols, cosh, sinh, log >>> x = symbols('x') >>> _is_lambert(3*log(x) - x*log(3), x) True >>> _is_lambert(log(log(x - 3)) + log(x-3), x) True >>> _is_lambert(cosh(x) - sinh(x), x) False >>> _is_lambert((x**2 - 2*x + 1).subs(x, (log(x) + 3*x)**2 - 1), x) True See Also ======== _solve_lambert """ term_factors = list(_term_factors(f.expand())) # total number of symbols in equation no_of_symbols = len([arg for arg in term_factors if arg.has(symbol)]) # total number of trigonometric terms in equation no_of_trig = len([arg for arg in term_factors \ if arg.has(HyperbolicFunction, TrigonometricFunction)]) if f.is_Add and no_of_symbols >= 2: # `log`, `HyperbolicFunction`, `TrigonometricFunction` should have symbols # and no_of_trig < no_of_symbols lambert_funcs = (log, HyperbolicFunction, TrigonometricFunction) if any(isinstance(arg, lambert_funcs)\ for arg in term_factors if arg.has(symbol)): if no_of_trig < no_of_symbols: return True # here, `Pow`, `exp` exponent should have symbols elif any(isinstance(arg, (Pow, exp)) \ for arg in term_factors if (arg.as_base_exp()[1]).has(symbol)): return True return False def _transolve(f, symbol, domain): r""" Function to solve transcendental equations. It is a helper to ``solveset`` and should be used internally. ``_transolve`` currently supports the following class of equations: - Exponential equations - Logarithmic equations Parameters ========== f : Any transcendental equation that needs to be solved. This needs to be an expression, which is assumed to be equal to ``0``. symbol : The variable for which the equation is solved. This needs to be of class ``Symbol``. domain : A set over which the equation is solved. This needs to be of class ``Set``. Returns ======= Set A set of values for ``symbol`` for which ``f`` is equal to zero. An ``EmptySet`` is returned if ``f`` does not have solutions in respective domain. A ``ConditionSet`` is returned as unsolved object if algorithms to evaluate complete solution are not yet implemented. How to use ``_transolve`` ========================= ``_transolve`` should not be used as an independent function, because it assumes that the equation (``f``) and the ``symbol`` comes from ``solveset`` and might have undergone a few modification(s). To use ``_transolve`` as an independent function the equation (``f``) and the ``symbol`` should be passed as they would have been by ``solveset``. Examples ======== >>> from sympy.solvers.solveset import _transolve as transolve >>> from sympy.solvers.solvers import _tsolve as tsolve >>> from sympy import symbols, S, pprint >>> x = symbols('x', real=True) # assumption added >>> transolve(5**(x - 3) - 3**(2*x + 1), x, S.Reals) FiniteSet(-(log(3) + 3*log(5))/(-log(5) + 2*log(3))) How ``_transolve`` works ======================== ``_transolve`` uses two types of helper functions to solve equations of a particular class: Identifying helpers: To determine whether a given equation belongs to a certain class of equation or not. Returns either ``True`` or ``False``. Solving helpers: Once an equation is identified, a corresponding helper either solves the equation or returns a form of the equation that ``solveset`` might better be able to handle. * Philosophy behind the module The purpose of ``_transolve`` is to take equations which are not already polynomial in their generator(s) and to either recast them as such through a valid transformation or to solve them outright. A pair of helper functions for each class of supported transcendental functions are employed for this purpose. One identifies the transcendental form of an equation and the other either solves it or recasts it into a tractable form that can be solved by ``solveset``. For example, an equation in the form `ab^{f(x)} - cd^{g(x)} = 0` can be transformed to `\log(a) + f(x)\log(b) - \log(c) - g(x)\log(d) = 0` (under certain assumptions) and this can be solved with ``solveset`` if `f(x)` and `g(x)` are in polynomial form. How ``_transolve`` is better than ``_tsolve`` ============================================= 1) Better output ``_transolve`` provides expressions in a more simplified form. Consider a simple exponential equation >>> f = 3**(2*x) - 2**(x + 3) >>> pprint(transolve(f, x, S.Reals), use_unicode=False) -3*log(2) {------------------} -2*log(3) + log(2) >>> pprint(tsolve(f, x), use_unicode=False) / 3 \ | --------| | log(2/9)| [-log\2 /] 2) Extensible The API of ``_transolve`` is designed such that it is easily extensible, i.e. the code that solves a given class of equations is encapsulated in a helper and not mixed in with the code of ``_transolve`` itself. 3) Modular ``_transolve`` is designed to be modular i.e, for every class of equation a separate helper for identification and solving is implemented. This makes it easy to change or modify any of the method implemented directly in the helpers without interfering with the actual structure of the API. 4) Faster Computation Solving equation via ``_transolve`` is much faster as compared to ``_tsolve``. In ``solve``, attempts are made computing every possibility to get the solutions. This series of attempts makes solving a bit slow. In ``_transolve``, computation begins only after a particular type of equation is identified. How to add new class of equations ================================= Adding a new class of equation solver is a three-step procedure: - Identify the type of the equations Determine the type of the class of equations to which they belong: it could be of ``Add``, ``Pow``, etc. types. Separate internal functions are used for each type. Write identification and solving helpers and use them from within the routine for the given type of equation (after adding it, if necessary). Something like: .. code-block:: python def add_type(lhs, rhs, x): .... if _is_exponential(lhs, x): new_eq = _solve_exponential(lhs, rhs, x) .... rhs, lhs = eq.as_independent(x) if lhs.is_Add: result = add_type(lhs, rhs, x) - Define the identification helper. - Define the solving helper. Apart from this, a few other things needs to be taken care while adding an equation solver: - Naming conventions: Name of the identification helper should be as ``_is_class`` where class will be the name or abbreviation of the class of equation. The solving helper will be named as ``_solve_class``. For example: for exponential equations it becomes ``_is_exponential`` and ``_solve_expo``. - The identifying helpers should take two input parameters, the equation to be checked and the variable for which a solution is being sought, while solving helpers would require an additional domain parameter. - Be sure to consider corner cases. - Add tests for each helper. - Add a docstring to your helper that describes the method implemented. The documentation of the helpers should identify: - the purpose of the helper, - the method used to identify and solve the equation, - a proof of correctness - the return values of the helpers """ def add_type(lhs, rhs, symbol, domain): """ Helper for ``_transolve`` to handle equations of ``Add`` type, i.e. equations taking the form as ``a*f(x) + b*g(x) + .... = c``. For example: 4**x + 8**x = 0 """ result = ConditionSet(symbol, Eq(lhs - rhs, 0), domain) # check if it is exponential type equation if _is_exponential(lhs, symbol): result = _solve_exponential(lhs, rhs, symbol, domain) # check if it is logarithmic type equation elif _is_logarithmic(lhs, symbol): result = _solve_logarithm(lhs, rhs, symbol, domain) return result result = ConditionSet(symbol, Eq(f, 0), domain) # invert_complex handles the call to the desired inverter based # on the domain specified. lhs, rhs_s = invert_complex(f, 0, symbol, domain) if isinstance(rhs_s, FiniteSet): assert (len(rhs_s.args)) == 1 rhs = rhs_s.args[0] if lhs.is_Add: result = add_type(lhs, rhs, symbol, domain) else: result = rhs_s return result def solveset(f, symbol=None, domain=S.Complexes): r"""Solves a given inequality or equation with set as output Parameters ========== f : Expr or a relational. The target equation or inequality symbol : Symbol The variable for which the equation is solved domain : Set The domain over which the equation is solved Returns ======= Set A set of values for `symbol` for which `f` is True or is equal to zero. An `EmptySet` is returned if `f` is False or nonzero. A `ConditionSet` is returned as unsolved object if algorithms to evaluate complete solution are not yet implemented. `solveset` claims to be complete in the solution set that it returns. Raises ====== NotImplementedError The algorithms to solve inequalities in complex domain are not yet implemented. ValueError The input is not valid. RuntimeError It is a bug, please report to the github issue tracker. Notes ===== Python interprets 0 and 1 as False and True, respectively, but in this function they refer to solutions of an expression. So 0 and 1 return the Domain and EmptySet, respectively, while True and False return the opposite (as they are assumed to be solutions of relational expressions). See Also ======== solveset_real: solver for real domain solveset_complex: solver for complex domain Examples ======== >>> from sympy import exp, sin, Symbol, pprint, S, Eq >>> from sympy.solvers.solveset import solveset, solveset_real * The default domain is complex. Not specifying a domain will lead to the solving of the equation in the complex domain (and this is not affected by the assumptions on the symbol): >>> x = Symbol('x') >>> pprint(solveset(exp(x) - 1, x), use_unicode=False) {2*n*I*pi | n in Integers} >>> x = Symbol('x', real=True) >>> pprint(solveset(exp(x) - 1, x), use_unicode=False) {2*n*I*pi | n in Integers} * If you want to use `solveset` to solve the equation in the real domain, provide a real domain. (Using ``solveset_real`` does this automatically.) >>> R = S.Reals >>> x = Symbol('x') >>> solveset(exp(x) - 1, x, R) FiniteSet(0) >>> solveset_real(exp(x) - 1, x) FiniteSet(0) The solution is unaffected by assumptions on the symbol: >>> p = Symbol('p', positive=True) >>> pprint(solveset(p**2 - 4)) {-2, 2} When a conditionSet is returned, symbols with assumptions that would alter the set are replaced with more generic symbols: >>> i = Symbol('i', imaginary=True) >>> solveset(Eq(i**2 + i*sin(i), 1), i, domain=S.Reals) ConditionSet(_R, Eq(_R**2 + _R*sin(_R) - 1, 0), Reals) * Inequalities can be solved over the real domain only. Use of a complex domain leads to a NotImplementedError. >>> solveset(exp(x) > 1, x, R) Interval.open(0, oo) """ f = sympify(f) symbol = sympify(symbol) if f is S.true: return domain if f is S.false: return S.EmptySet if not isinstance(f, (Expr, Relational, Number)): raise ValueError("%s is not a valid SymPy expression" % f) if not isinstance(symbol, (Expr, Relational)) and symbol is not None: raise ValueError("%s is not a valid SymPy symbol" % (symbol,)) if not isinstance(domain, Set): raise ValueError("%s is not a valid domain" %(domain)) free_symbols = f.free_symbols if symbol is None and not free_symbols: b = Eq(f, 0) if b is S.true: return domain elif b is S.false: return S.EmptySet else: raise NotImplementedError(filldedent(''' relationship between value and 0 is unknown: %s''' % b)) if symbol is None: if len(free_symbols) == 1: symbol = free_symbols.pop() elif free_symbols: raise ValueError(filldedent(''' The independent variable must be specified for a multivariate equation.''')) elif not isinstance(symbol, Symbol): f, s, swap = recast_to_symbols([f], [symbol]) # the xreplace will be needed if a ConditionSet is returned return solveset(f[0], s[0], domain).xreplace(swap) # solveset should ignore assumptions on symbols if symbol not in _rc: x = _rc[0] if domain.is_subset(S.Reals) else _rc[1] rv = solveset(f.xreplace({symbol: x}), x, domain) # try to use the original symbol if possible try: _rv = rv.xreplace({x: symbol}) except TypeError: _rv = rv if rv.dummy_eq(_rv): rv = _rv return rv # Abs has its own handling method which avoids the # rewriting property that the first piece of abs(x) # is for x >= 0 and the 2nd piece for x < 0 -- solutions # can look better if the 2nd condition is x <= 0. Since # the solution is a set, duplication of results is not # an issue, e.g. {y, -y} when y is 0 will be {0} f, mask = _masked(f, Abs) f = f.rewrite(Piecewise) # everything that's not an Abs for d, e in mask: # everything *in* an Abs e = e.func(e.args[0].rewrite(Piecewise)) f = f.xreplace({d: e}) f = piecewise_fold(f) return _solveset(f, symbol, domain, _check=True) def solveset_real(f, symbol): return solveset(f, symbol, S.Reals) def solveset_complex(f, symbol): return solveset(f, symbol, S.Complexes) def _solveset_multi(eqs, syms, domains): '''Basic implementation of a multivariate solveset. For internal use (not ready for public consumption)''' rep = {} for sym, dom in zip(syms, domains): if dom is S.Reals: rep[sym] = Symbol(sym.name, real=True) eqs = [eq.subs(rep) for eq in eqs] syms = [sym.subs(rep) for sym in syms] syms = tuple(syms) if len(eqs) == 0: return ProductSet(*domains) if len(syms) == 1: sym = syms[0] domain = domains[0] solsets = [solveset(eq, sym, domain) for eq in eqs] solset = Intersection(*solsets) return ImageSet(Lambda((sym,), (sym,)), solset).doit() eqs = sorted(eqs, key=lambda eq: len(eq.free_symbols & set(syms))) for n in range(len(eqs)): sols = [] all_handled = True for sym in syms: if sym not in eqs[n].free_symbols: continue sol = solveset(eqs[n], sym, domains[syms.index(sym)]) if isinstance(sol, FiniteSet): i = syms.index(sym) symsp = syms[:i] + syms[i+1:] domainsp = domains[:i] + domains[i+1:] eqsp = eqs[:n] + eqs[n+1:] for s in sol: eqsp_sub = [eq.subs(sym, s) for eq in eqsp] sol_others = _solveset_multi(eqsp_sub, symsp, domainsp) fun = Lambda((symsp,), symsp[:i] + (s,) + symsp[i:]) sols.append(ImageSet(fun, sol_others).doit()) else: all_handled = False if all_handled: return Union(*sols) def solvify(f, symbol, domain): """Solves an equation using solveset and returns the solution in accordance with the `solve` output API. Returns ======= We classify the output based on the type of solution returned by `solveset`. Solution | Output ---------------------------------------- FiniteSet | list ImageSet, | list (if `f` is periodic) Union | Union | list (with FiniteSet) EmptySet | empty list Others | None Raises ====== NotImplementedError A ConditionSet is the input. Examples ======== >>> from sympy.solvers.solveset import solvify >>> from sympy.abc import x >>> from sympy import S, tan, sin, exp >>> solvify(x**2 - 9, x, S.Reals) [-3, 3] >>> solvify(sin(x) - 1, x, S.Reals) [pi/2] >>> solvify(tan(x), x, S.Reals) [0] >>> solvify(exp(x) - 1, x, S.Complexes) >>> solvify(exp(x) - 1, x, S.Reals) [0] """ solution_set = solveset(f, symbol, domain) result = None if solution_set is S.EmptySet: result = [] elif isinstance(solution_set, ConditionSet): raise NotImplementedError('solveset is unable to solve this equation.') elif isinstance(solution_set, FiniteSet): result = list(solution_set) else: period = periodicity(f, symbol) if period is not None: solutions = S.EmptySet iter_solutions = () if isinstance(solution_set, ImageSet): iter_solutions = (solution_set,) elif isinstance(solution_set, Union): if all(isinstance(i, ImageSet) for i in solution_set.args): iter_solutions = solution_set.args for solution in iter_solutions: solutions += solution.intersect(Interval(0, period, False, True)) if isinstance(solutions, FiniteSet): result = list(solutions) else: solution = solution_set.intersect(domain) if isinstance(solution, Union): # concerned about only FiniteSet with Union but not about ImageSet # if required could be extend if any(isinstance(i, FiniteSet) for i in solution.args): result = [sol for soln in solution.args \ for sol in soln.args if isinstance(soln,FiniteSet)] else: return None elif isinstance(solution, FiniteSet): result += solution return result ############################################################################### ################################ LINSOLVE ##################################### ############################################################################### def linear_coeffs(eq, *syms, **_kw): """Return a list whose elements are the coefficients of the corresponding symbols in the sum of terms in ``eq``. The additive constant is returned as the last element of the list. Raises ====== NonlinearError The equation contains a nonlinear term Examples ======== >>> from sympy.solvers.solveset import linear_coeffs >>> from sympy.abc import x, y, z >>> linear_coeffs(3*x + 2*y - 1, x, y) [3, 2, -1] It is not necessary to expand the expression: >>> linear_coeffs(x + y*(z*(x*3 + 2) + 3), x) [3*y*z + 1, y*(2*z + 3)] But if there are nonlinear or cross terms -- even if they would cancel after simplification -- an error is raised so the situation does not pass silently past the caller's attention: >>> eq = 1/x*(x - 1) + 1/x >>> linear_coeffs(eq.expand(), x) [0, 1] >>> linear_coeffs(eq, x) Traceback (most recent call last): ... NonlinearError: nonlinear term encountered: 1/x >>> linear_coeffs(x*(y + 1) - x*y, x, y) Traceback (most recent call last): ... NonlinearError: nonlinear term encountered: x*(y + 1) """ d = defaultdict(list) eq = _sympify(eq) symset = set(syms) has = eq.free_symbols & symset if not has: return [S.Zero]*len(syms) + [eq] c, terms = eq.as_coeff_add(*has) d[0].extend(Add.make_args(c)) for t in terms: m, f = t.as_coeff_mul(*has) if len(f) != 1: break f = f[0] if f in symset: d[f].append(m) elif f.is_Add: d1 = linear_coeffs(f, *has, **{'dict': True}) d[0].append(m*d1.pop(0)) for xf, vf in d1.items(): d[xf].append(m*vf) else: break else: for k, v in d.items(): d[k] = Add(*v) if not _kw: return [d.get(s, S.Zero) for s in syms] + [d[0]] return d # default is still list but this won't matter raise NonlinearError('nonlinear term encountered: %s' % t) def linear_eq_to_matrix(equations, *symbols): r""" Converts a given System of Equations into Matrix form. Here `equations` must be a linear system of equations in `symbols`. Element M[i, j] corresponds to the coefficient of the jth symbol in the ith equation. The Matrix form corresponds to the augmented matrix form. For example: .. math:: 4x + 2y + 3z = 1 .. math:: 3x + y + z = -6 .. math:: 2x + 4y + 9z = 2 This system would return `A` & `b` as given below: :: [ 4 2 3 ] [ 1 ] A = [ 3 1 1 ] b = [-6 ] [ 2 4 9 ] [ 2 ] The only simplification performed is to convert `Eq(a, b) -> a - b`. Raises ====== NonlinearError The equations contain a nonlinear term. ValueError The symbols are not given or are not unique. Examples ======== >>> from sympy import linear_eq_to_matrix, symbols >>> c, x, y, z = symbols('c, x, y, z') The coefficients (numerical or symbolic) of the symbols will be returned as matrices: >>> eqns = [c*x + z - 1 - c, y + z, x - y] >>> A, b = linear_eq_to_matrix(eqns, [x, y, z]) >>> A Matrix([ [c, 0, 1], [0, 1, 1], [1, -1, 0]]) >>> b Matrix([ [c + 1], [ 0], [ 0]]) This routine does not simplify expressions and will raise an error if nonlinearity is encountered: >>> eqns = [ ... (x**2 - 3*x)/(x - 3) - 3, ... y**2 - 3*y - y*(y - 4) + x - 4] >>> linear_eq_to_matrix(eqns, [x, y]) Traceback (most recent call last): ... NonlinearError: The term (x**2 - 3*x)/(x - 3) is nonlinear in {x, y} Simplifying these equations will discard the removable singularity in the first, reveal the linear structure of the second: >>> [e.simplify() for e in eqns] [x - 3, x + y - 4] Any such simplification needed to eliminate nonlinear terms must be done before calling this routine. """ if not symbols: raise ValueError(filldedent(''' Symbols must be given, for which coefficients are to be found. ''')) if hasattr(symbols[0], '__iter__'): symbols = symbols[0] for i in symbols: if not isinstance(i, Symbol): raise ValueError(filldedent(''' Expecting a Symbol but got %s ''' % i)) if has_dups(symbols): raise ValueError('Symbols must be unique') equations = sympify(equations) if isinstance(equations, MatrixBase): equations = list(equations) elif isinstance(equations, (Expr, Eq)): equations = [equations] elif not is_sequence(equations): raise ValueError(filldedent(''' Equation(s) must be given as a sequence, Expr, Eq or Matrix. ''')) A, b = [], [] for i, f in enumerate(equations): if isinstance(f, Equality): f = f.rewrite(Add, evaluate=False) coeff_list = linear_coeffs(f, *symbols) b.append(-coeff_list.pop()) A.append(coeff_list) A, b = map(Matrix, (A, b)) return A, b def linsolve(system, *symbols): r""" Solve system of N linear equations with M variables; both underdetermined and overdetermined systems are supported. The possible number of solutions is zero, one or infinite. Zero solutions throws a ValueError, whereas infinite solutions are represented parametrically in terms of the given symbols. For unique solution a FiniteSet of ordered tuples is returned. All Standard input formats are supported: For the given set of Equations, the respective input types are given below: .. math:: 3x + 2y - z = 1 .. math:: 2x - 2y + 4z = -2 .. math:: 2x - y + 2z = 0 * Augmented Matrix Form, `system` given below: :: [3 2 -1 1] system = [2 -2 4 -2] [2 -1 2 0] * List Of Equations Form `system = [3x + 2y - z - 1, 2x - 2y + 4z + 2, 2x - y + 2z]` * Input A & b Matrix Form (from Ax = b) are given as below: :: [3 2 -1 ] [ 1 ] A = [2 -2 4 ] b = [ -2 ] [2 -1 2 ] [ 0 ] `system = (A, b)` Symbols can always be passed but are actually only needed when 1) a system of equations is being passed and 2) the system is passed as an underdetermined matrix and one wants to control the name of the free variables in the result. An error is raised if no symbols are used for case 1, but if no symbols are provided for case 2, internally generated symbols will be provided. When providing symbols for case 2, there should be at least as many symbols are there are columns in matrix A. The algorithm used here is Gauss-Jordan elimination, which results, after elimination, in a row echelon form matrix. Returns ======= A FiniteSet containing an ordered tuple of values for the unknowns for which the `system` has a solution. (Wrapping the tuple in FiniteSet is used to maintain a consistent output format throughout solveset.) Returns EmptySet, if the linear system is inconsistent. Raises ====== ValueError The input is not valid. The symbols are not given. Examples ======== >>> from sympy import Matrix, linsolve, symbols >>> x, y, z = symbols("x, y, z") >>> A = Matrix([[1, 2, 3], [4, 5, 6], [7, 8, 10]]) >>> b = Matrix([3, 6, 9]) >>> A Matrix([ [1, 2, 3], [4, 5, 6], [7, 8, 10]]) >>> b Matrix([ [3], [6], [9]]) >>> linsolve((A, b), [x, y, z]) FiniteSet((-1, 2, 0)) * Parametric Solution: In case the system is underdetermined, the function will return a parametric solution in terms of the given symbols. Those that are free will be returned unchanged. e.g. in the system below, `z` is returned as the solution for variable z; it can take on any value. >>> A = Matrix([[1, 2, 3], [4, 5, 6], [7, 8, 9]]) >>> b = Matrix([3, 6, 9]) >>> linsolve((A, b), x, y, z) FiniteSet((z - 1, 2 - 2*z, z)) If no symbols are given, internally generated symbols will be used. The `tau0` in the 3rd position indicates (as before) that the 3rd variable -- whatever it's named -- can take on any value: >>> linsolve((A, b)) FiniteSet((tau0 - 1, 2 - 2*tau0, tau0)) * List of Equations as input >>> Eqns = [3*x + 2*y - z - 1, 2*x - 2*y + 4*z + 2, - x + y/2 - z] >>> linsolve(Eqns, x, y, z) FiniteSet((1, -2, -2)) * Augmented Matrix as input >>> aug = Matrix([[2, 1, 3, 1], [2, 6, 8, 3], [6, 8, 18, 5]]) >>> aug Matrix([ [2, 1, 3, 1], [2, 6, 8, 3], [6, 8, 18, 5]]) >>> linsolve(aug, x, y, z) FiniteSet((3/10, 2/5, 0)) * Solve for symbolic coefficients >>> a, b, c, d, e, f = symbols('a, b, c, d, e, f') >>> eqns = [a*x + b*y - c, d*x + e*y - f] >>> linsolve(eqns, x, y) FiniteSet(((-b*f + c*e)/(a*e - b*d), (a*f - c*d)/(a*e - b*d))) * A degenerate system returns solution as set of given symbols. >>> system = Matrix(([0, 0, 0], [0, 0, 0], [0, 0, 0])) >>> linsolve(system, x, y) FiniteSet((x, y)) * For an empty system linsolve returns empty set >>> linsolve([], x) EmptySet * An error is raised if, after expansion, any nonlinearity is detected: >>> linsolve([x*(1/x - 1), (y - 1)**2 - y**2 + 1], x, y) FiniteSet((1, 1)) >>> linsolve([x**2 - 1], x) Traceback (most recent call last): ... NonlinearError: nonlinear term encountered: x**2 """ if not system: return S.EmptySet # If second argument is an iterable if symbols and hasattr(symbols[0], '__iter__'): symbols = symbols[0] sym_gen = isinstance(symbols, GeneratorType) b = None # if we don't get b the input was bad syms_needed_msg = None # unpack system if hasattr(system, '__iter__'): # 1). (A, b) if len(system) == 2 and isinstance(system[0], MatrixBase): A, b = system # 2). (eq1, eq2, ...) if not isinstance(system[0], MatrixBase): if sym_gen or not symbols: raise ValueError(filldedent(''' When passing a system of equations, the explicit symbols for which a solution is being sought must be given as a sequence, too. ''')) # # Pass to the sparse solver implemented in polys. It is important # that we do not attempt to convert the equations to a matrix # because that would be very inefficient for large sparse systems # of equations. # eqs = system eqs = [sympify(eq) for eq in eqs] try: sol = _linsolve(eqs, symbols) except PolyNonlinearError as exc: # e.g. cos(x) contains an element of the set of generators raise NonlinearError(str(exc)) if sol is None: return S.EmptySet sol = FiniteSet(Tuple(*(sol.get(sym, sym) for sym in symbols))) return sol elif isinstance(system, MatrixBase) and not ( symbols and not isinstance(symbols, GeneratorType) and isinstance(symbols[0], MatrixBase)): # 3). A augmented with b A, b = system[:, :-1], system[:, -1:] if b is None: raise ValueError("Invalid arguments") syms_needed_msg = syms_needed_msg or 'columns of A' if sym_gen: symbols = [next(symbols) for i in range(A.cols)] if any(set(symbols) & (A.free_symbols | b.free_symbols)): raise ValueError(filldedent(''' At least one of the symbols provided already appears in the system to be solved. One way to avoid this is to use Dummy symbols in the generator, e.g. numbered_symbols('%s', cls=Dummy) ''' % symbols[0].name.rstrip('1234567890'))) if not symbols: symbols = [Dummy() for _ in range(A.cols)] name = _uniquely_named_symbol('tau', (A, b), compare=lambda i: str(i).rstrip('1234567890')).name gen = numbered_symbols(name) else: gen = None # This is just a wrapper for solve_lin_sys eqs = [] rows = A.tolist() for rowi, bi in zip(rows, b): terms = [elem * sym for elem, sym in zip(rowi, symbols) if elem] terms.append(-bi) eqs.append(Add(*terms)) eqs, ring = sympy_eqs_to_ring(eqs, symbols) sol = solve_lin_sys(eqs, ring, _raw=False) if sol is None: return S.EmptySet #sol = {sym:val for sym, val in sol.items() if sym != val} sol = FiniteSet(Tuple(*(sol.get(sym, sym) for sym in symbols))) if gen is not None: solsym = sol.free_symbols rep = {sym: next(gen) for sym in symbols if sym in solsym} sol = sol.subs(rep) return sol ############################################################################## # ------------------------------nonlinsolve ---------------------------------# ############################################################################## def _return_conditionset(eqs, symbols): # return conditionset eqs = (Eq(lhs, 0) for lhs in eqs) condition_set = ConditionSet( Tuple(*symbols), And(*eqs), S.Complexes**len(symbols)) return condition_set def substitution(system, symbols, result=[{}], known_symbols=[], exclude=[], all_symbols=None): r""" Solves the `system` using substitution method. It is used in `nonlinsolve`. This will be called from `nonlinsolve` when any equation(s) is non polynomial equation. Parameters ========== system : list of equations The target system of equations symbols : list of symbols to be solved. The variable(s) for which the system is solved known_symbols : list of solved symbols Values are known for these variable(s) result : An empty list or list of dict If No symbol values is known then empty list otherwise symbol as keys and corresponding value in dict. exclude : Set of expression. Mostly denominator expression(s) of the equations of the system. Final solution should not satisfy these expressions. all_symbols : known_symbols + symbols(unsolved). Returns ======= A FiniteSet of ordered tuple of values of `all_symbols` for which the `system` has solution. Order of values in the tuple is same as symbols present in the parameter `all_symbols`. If parameter `all_symbols` is None then same as symbols present in the parameter `symbols`. Please note that general FiniteSet is unordered, the solution returned here is not simply a FiniteSet of solutions, rather it is a FiniteSet of ordered tuple, i.e. the first & only argument to FiniteSet is a tuple of solutions, which is ordered, & hence the returned solution is ordered. Also note that solution could also have been returned as an ordered tuple, FiniteSet is just a wrapper `{}` around the tuple. It has no other significance except for the fact it is just used to maintain a consistent output format throughout the solveset. Raises ====== ValueError The input is not valid. The symbols are not given. AttributeError The input symbols are not `Symbol` type. Examples ======== >>> from sympy.core.symbol import symbols >>> x, y = symbols('x, y', real=True) >>> from sympy.solvers.solveset import substitution >>> substitution([x + y], [x], [{y: 1}], [y], set([]), [x, y]) FiniteSet((-1, 1)) * when you want soln should not satisfy eq `x + 1 = 0` >>> substitution([x + y], [x], [{y: 1}], [y], set([x + 1]), [y, x]) EmptySet >>> substitution([x + y], [x], [{y: 1}], [y], set([x - 1]), [y, x]) FiniteSet((1, -1)) >>> substitution([x + y - 1, y - x**2 + 5], [x, y]) FiniteSet((-3, 4), (2, -1)) * Returns both real and complex solution >>> x, y, z = symbols('x, y, z') >>> from sympy import exp, sin >>> substitution([exp(x) - sin(y), y**2 - 4], [x, y]) FiniteSet((ImageSet(Lambda(_n, 2*_n*I*pi + log(sin(2))), Integers), 2), (ImageSet(Lambda(_n, I*(2*_n*pi + pi) + log(sin(2))), Integers), -2)) >>> eqs = [z**2 + exp(2*x) - sin(y), -3 + exp(-y)] >>> substitution(eqs, [y, z]) FiniteSet((-log(3), sqrt(-exp(2*x) - sin(log(3)))), (-log(3), -sqrt(-exp(2*x) - sin(log(3)))), (ImageSet(Lambda(_n, 2*_n*I*pi - log(3)), Integers), ImageSet(Lambda(_n, sqrt(-exp(2*x) + sin(2*_n*I*pi - log(3)))), Integers)), (ImageSet(Lambda(_n, 2*_n*I*pi - log(3)), Integers), ImageSet(Lambda(_n, -sqrt(-exp(2*x) + sin(2*_n*I*pi - log(3)))), Integers))) """ from sympy import Complement from sympy.core.compatibility import is_sequence if not system: return S.EmptySet if not symbols: msg = ('Symbols must be given, for which solution of the ' 'system is to be found.') raise ValueError(filldedent(msg)) if not is_sequence(symbols): msg = ('symbols should be given as a sequence, e.g. a list.' 'Not type %s: %s') raise TypeError(filldedent(msg % (type(symbols), symbols))) if not getattr(symbols[0], 'is_Symbol', False): msg = ('Iterable of symbols must be given as ' 'second argument, not type %s: %s') raise ValueError(filldedent(msg % (type(symbols[0]), symbols[0]))) # By default `all_symbols` will be same as `symbols` if all_symbols is None: all_symbols = symbols old_result = result # storing complements and intersection for particular symbol complements = {} intersections = {} # when total_solveset_call equals total_conditionset # it means that solveset failed to solve all eqs. total_conditionset = -1 total_solveset_call = -1 def _unsolved_syms(eq, sort=False): """Returns the unsolved symbol present in the equation `eq`. """ free = eq.free_symbols unsolved = (free - set(known_symbols)) & set(all_symbols) if sort: unsolved = list(unsolved) unsolved.sort(key=default_sort_key) return unsolved # end of _unsolved_syms() # sort such that equation with the fewest potential symbols is first. # means eq with less number of variable first in the list. eqs_in_better_order = list( ordered(system, lambda _: len(_unsolved_syms(_)))) def add_intersection_complement(result, intersection_dict, complement_dict): # If solveset has returned some intersection/complement # for any symbol, it will be added in the final solution. final_result = [] for res in result: res_copy = res for key_res, value_res in res.items(): intersect_set, complement_set = None, None for key_sym, value_sym in intersection_dict.items(): if key_sym == key_res: intersect_set = value_sym for key_sym, value_sym in complement_dict.items(): if key_sym == key_res: complement_set = value_sym if intersect_set or complement_set: new_value = FiniteSet(value_res) if intersect_set and intersect_set != S.Complexes: new_value = Intersection(new_value, intersect_set) if complement_set: new_value = Complement(new_value, complement_set) if new_value is S.EmptySet: res_copy = None break elif new_value.is_FiniteSet and len(new_value) == 1: res_copy[key_res] = set(new_value).pop() else: res_copy[key_res] = new_value if res_copy is not None: final_result.append(res_copy) return final_result # end of def add_intersection_complement() def _extract_main_soln(sym, sol, soln_imageset): """Separate the Complements, Intersections, ImageSet lambda expr and its base_set. This function returns the unmasks sol from different classes of sets and also returns the appended ImageSet elements in a soln_imageset (dict: where key as unmasked element and value as ImageSet). """ # if there is union, then need to check # Complement, Intersection, Imageset. # Order should not be changed. if isinstance(sol, ConditionSet): # extracts any solution in ConditionSet sol = sol.base_set if isinstance(sol, Complement): # extract solution and complement complements[sym] = sol.args[1] sol = sol.args[0] # complement will be added at the end # using `add_intersection_complement` method # if there is union of Imageset or other in soln. # no testcase is written for this if block if isinstance(sol, Union): sol_args = sol.args sol = S.EmptySet # We need in sequence so append finteset elements # and then imageset or other. for sol_arg2 in sol_args: if isinstance(sol_arg2, FiniteSet): sol += sol_arg2 else: # ImageSet, Intersection, complement then # append them directly sol += FiniteSet(sol_arg2) if isinstance(sol, Intersection): # Interval/Set will be at 0th index always if sol.args[0] not in (S.Reals, S.Complexes): # Sometimes solveset returns soln with intersection # S.Reals or S.Complexes. We don't consider that # intersection. intersections[sym] = sol.args[0] sol = sol.args[1] # after intersection and complement Imageset should # be checked. if isinstance(sol, ImageSet): soln_imagest = sol expr2 = sol.lamda.expr sol = FiniteSet(expr2) soln_imageset[expr2] = soln_imagest if not isinstance(sol, FiniteSet): sol = FiniteSet(sol) return sol, soln_imageset # end of def _extract_main_soln() # helper function for _append_new_soln def _check_exclude(rnew, imgset_yes): rnew_ = rnew if imgset_yes: # replace all dummy variables (Imageset lambda variables) # with zero before `checksol`. Considering fundamental soln # for `checksol`. rnew_copy = rnew.copy() dummy_n = imgset_yes[0] for key_res, value_res in rnew_copy.items(): rnew_copy[key_res] = value_res.subs(dummy_n, 0) rnew_ = rnew_copy # satisfy_exclude == true if it satisfies the expr of `exclude` list. try: # something like : `Mod(-log(3), 2*I*pi)` can't be # simplified right now, so `checksol` returns `TypeError`. # when this issue is fixed this try block should be # removed. Mod(-log(3), 2*I*pi) == -log(3) satisfy_exclude = any( checksol(d, rnew_) for d in exclude) except TypeError: satisfy_exclude = None return satisfy_exclude # end of def _check_exclude() # helper function for _append_new_soln def _restore_imgset(rnew, original_imageset, newresult): restore_sym = set(rnew.keys()) & \ set(original_imageset.keys()) for key_sym in restore_sym: img = original_imageset[key_sym] rnew[key_sym] = img if rnew not in newresult: newresult.append(rnew) # end of def _restore_imgset() def _append_eq(eq, result, res, delete_soln, n=None): u = Dummy('u') if n: eq = eq.subs(n, 0) satisfy = eq if eq in (True, False) else checksol(u, u, eq, minimal=True) if satisfy is False: delete_soln = True res = {} else: result.append(res) return result, res, delete_soln def _append_new_soln(rnew, sym, sol, imgset_yes, soln_imageset, original_imageset, newresult, eq=None): """If `rnew` (A dict <symbol: soln>) contains valid soln append it to `newresult` list. `imgset_yes` is (base, dummy_var) if there was imageset in previously calculated result(otherwise empty tuple). `original_imageset` is dict of imageset expr and imageset from this result. `soln_imageset` dict of imageset expr and imageset of new soln. """ satisfy_exclude = _check_exclude(rnew, imgset_yes) delete_soln = False # soln should not satisfy expr present in `exclude` list. if not satisfy_exclude: local_n = None # if it is imageset if imgset_yes: local_n = imgset_yes[0] base = imgset_yes[1] if sym and sol: # when `sym` and `sol` is `None` means no new # soln. In that case we will append rnew directly after # substituting original imagesets in rnew values if present # (second last line of this function using _restore_imgset) dummy_list = list(sol.atoms(Dummy)) # use one dummy `n` which is in # previous imageset local_n_list = [ local_n for i in range( 0, len(dummy_list))] dummy_zip = zip(dummy_list, local_n_list) lam = Lambda(local_n, sol.subs(dummy_zip)) rnew[sym] = ImageSet(lam, base) if eq is not None: newresult, rnew, delete_soln = _append_eq( eq, newresult, rnew, delete_soln, local_n) elif eq is not None: newresult, rnew, delete_soln = _append_eq( eq, newresult, rnew, delete_soln) elif sol in soln_imageset.keys(): rnew[sym] = soln_imageset[sol] # restore original imageset _restore_imgset(rnew, original_imageset, newresult) else: newresult.append(rnew) elif satisfy_exclude: delete_soln = True rnew = {} _restore_imgset(rnew, original_imageset, newresult) return newresult, delete_soln # end of def _append_new_soln() def _new_order_result(result, eq): # separate first, second priority. `res` that makes `eq` value equals # to zero, should be used first then other result(second priority). # If it is not done then we may miss some soln. first_priority = [] second_priority = [] for res in result: if not any(isinstance(val, ImageSet) for val in res.values()): if eq.subs(res) == 0: first_priority.append(res) else: second_priority.append(res) if first_priority or second_priority: return first_priority + second_priority return result def _solve_using_known_values(result, solver): """Solves the system using already known solution (result contains the dict <symbol: value>). solver is `solveset_complex` or `solveset_real`. """ # stores imageset <expr: imageset(Lambda(n, expr), base)>. soln_imageset = {} total_solvest_call = 0 total_conditionst = 0 # sort such that equation with the fewest potential symbols is first. # means eq with less variable first for index, eq in enumerate(eqs_in_better_order): newresult = [] original_imageset = {} # if imageset expr is used to solve other symbol imgset_yes = False result = _new_order_result(result, eq) for res in result: got_symbol = set() # symbols solved in one iteration # find the imageset and use its expr. for key_res, value_res in res.items(): if isinstance(value_res, ImageSet): res[key_res] = value_res.lamda.expr original_imageset[key_res] = value_res dummy_n = value_res.lamda.expr.atoms(Dummy).pop() (base,) = value_res.base_sets imgset_yes = (dummy_n, base) # update eq with everything that is known so far eq2 = eq.subs(res).expand() unsolved_syms = _unsolved_syms(eq2, sort=True) if not unsolved_syms: if res: newresult, delete_res = _append_new_soln( res, None, None, imgset_yes, soln_imageset, original_imageset, newresult, eq2) if delete_res: # `delete_res` is true, means substituting `res` in # eq2 doesn't return `zero` or deleting the `res` # (a soln) since it staisfies expr of `exclude` # list. result.remove(res) continue # skip as it's independent of desired symbols depen1, depen2 = (eq2.rewrite(Add)).as_independent(*unsolved_syms) if (depen1.has(Abs) or depen2.has(Abs)) and solver == solveset_complex: # Absolute values cannot be inverted in the # complex domain continue soln_imageset = {} for sym in unsolved_syms: not_solvable = False try: soln = solver(eq2, sym) total_solvest_call += 1 soln_new = S.EmptySet if isinstance(soln, Complement): # separate solution and complement complements[sym] = soln.args[1] soln = soln.args[0] # complement will be added at the end if isinstance(soln, Intersection): # Interval will be at 0th index always if soln.args[0] != Interval(-oo, oo): # sometimes solveset returns soln # with intersection S.Reals, to confirm that # soln is in domain=S.Reals intersections[sym] = soln.args[0] soln_new += soln.args[1] soln = soln_new if soln_new else soln if index > 0 and solver == solveset_real: # one symbol's real soln , another symbol may have # corresponding complex soln. if not isinstance(soln, (ImageSet, ConditionSet)): soln += solveset_complex(eq2, sym) except NotImplementedError: # If sovleset is not able to solve equation `eq2`. Next # time we may get soln using next equation `eq2` continue if isinstance(soln, ConditionSet): if soln.base_set in (S.Reals, S.Complexes): soln = S.EmptySet # don't do `continue` we may get soln # in terms of other symbol(s) not_solvable = True total_conditionst += 1 else: soln = soln.base_set if soln is not S.EmptySet: soln, soln_imageset = _extract_main_soln( sym, soln, soln_imageset) for sol in soln: # sol is not a `Union` since we checked it # before this loop sol, soln_imageset = _extract_main_soln( sym, sol, soln_imageset) sol = set(sol).pop() free = sol.free_symbols if got_symbol and any([ ss in free for ss in got_symbol ]): # sol depends on previously solved symbols # then continue continue rnew = res.copy() # put each solution in res and append the new result # in the new result list (solution for symbol `s`) # along with old results. for k, v in res.items(): if isinstance(v, Expr): # if any unsolved symbol is present # Then subs known value rnew[k] = v.subs(sym, sol) # and add this new solution if sol in soln_imageset.keys(): # replace all lambda variables with 0. imgst = soln_imageset[sol] rnew[sym] = imgst.lamda( *[0 for i in range(0, len( imgst.lamda.variables))]) else: rnew[sym] = sol newresult, delete_res = _append_new_soln( rnew, sym, sol, imgset_yes, soln_imageset, original_imageset, newresult) if delete_res: # deleting the `res` (a soln) since it staisfies # eq of `exclude` list result.remove(res) # solution got for sym if not not_solvable: got_symbol.add(sym) # next time use this new soln if newresult: result = newresult return result, total_solvest_call, total_conditionst # end def _solve_using_know_values() new_result_real, solve_call1, cnd_call1 = _solve_using_known_values( old_result, solveset_real) new_result_complex, solve_call2, cnd_call2 = _solve_using_known_values( old_result, solveset_complex) # If total_solveset_call is equal to total_conditionset # then solveset failed to solve all of the equations. # In this case we return a ConditionSet here. total_conditionset += (cnd_call1 + cnd_call2) total_solveset_call += (solve_call1 + solve_call2) if total_conditionset == total_solveset_call and total_solveset_call != -1: return _return_conditionset(eqs_in_better_order, all_symbols) # don't keep duplicate solutions filtered_complex = [] for i in list(new_result_complex): for j in list(new_result_real): if i.keys() != j.keys(): continue if all(a.dummy_eq(b) for a, b in zip(i.values(), j.values()) \ if type(a) != int or type(b) != int): break else: filtered_complex.append(i) # overall result result = new_result_real + filtered_complex result_all_variables = [] result_infinite = [] for res in result: if not res: # means {None : None} continue # If length < len(all_symbols) means infinite soln. # Some or all the soln is dependent on 1 symbol. # eg. {x: y+2} then final soln {x: y+2, y: y} if len(res) < len(all_symbols): solved_symbols = res.keys() unsolved = list(filter( lambda x: x not in solved_symbols, all_symbols)) for unsolved_sym in unsolved: res[unsolved_sym] = unsolved_sym result_infinite.append(res) if res not in result_all_variables: result_all_variables.append(res) if result_infinite: # we have general soln # eg : [{x: -1, y : 1}, {x : -y , y: y}] then # return [{x : -y, y : y}] result_all_variables = result_infinite if intersections or complements: result_all_variables = add_intersection_complement( result_all_variables, intersections, complements) # convert to ordered tuple result = S.EmptySet for r in result_all_variables: temp = [r[symb] for symb in all_symbols] result += FiniteSet(tuple(temp)) return result # end of def substitution() def _solveset_work(system, symbols): soln = solveset(system[0], symbols[0]) if isinstance(soln, FiniteSet): _soln = FiniteSet(*[tuple((s,)) for s in soln]) return _soln else: return FiniteSet(tuple(FiniteSet(soln))) def _handle_positive_dimensional(polys, symbols, denominators): from sympy.polys.polytools import groebner # substitution method where new system is groebner basis of the system _symbols = list(symbols) _symbols.sort(key=default_sort_key) basis = groebner(polys, _symbols, polys=True) new_system = [] for poly_eq in basis: new_system.append(poly_eq.as_expr()) result = [{}] result = substitution( new_system, symbols, result, [], denominators) return result # end of def _handle_positive_dimensional() def _handle_zero_dimensional(polys, symbols, system): # solve 0 dimensional poly system using `solve_poly_system` result = solve_poly_system(polys, *symbols) # May be some extra soln is added because # we used `unrad` in `_separate_poly_nonpoly`, so # need to check and remove if it is not a soln. result_update = S.EmptySet for res in result: dict_sym_value = dict(list(zip(symbols, res))) if all(checksol(eq, dict_sym_value) for eq in system): result_update += FiniteSet(res) return result_update # end of def _handle_zero_dimensional() def _separate_poly_nonpoly(system, symbols): polys = [] polys_expr = [] nonpolys = [] denominators = set() poly = None for eq in system: # Store denom expression if it contains symbol denominators.update(_simple_dens(eq, symbols)) # try to remove sqrt and rational power without_radicals = unrad(simplify(eq)) if without_radicals: eq_unrad, cov = without_radicals if not cov: eq = eq_unrad if isinstance(eq, Expr): eq = eq.as_numer_denom()[0] poly = eq.as_poly(*symbols, extension=True) elif simplify(eq).is_number: continue if poly is not None: polys.append(poly) polys_expr.append(poly.as_expr()) else: nonpolys.append(eq) return polys, polys_expr, nonpolys, denominators # end of def _separate_poly_nonpoly() def nonlinsolve(system, *symbols): r""" Solve system of N nonlinear equations with M variables, which means both under and overdetermined systems are supported. Positive dimensional system is also supported (A system with infinitely many solutions is said to be positive-dimensional). In Positive dimensional system solution will be dependent on at least one symbol. Returns both real solution and complex solution(If system have). The possible number of solutions is zero, one or infinite. Parameters ========== system : list of equations The target system of equations symbols : list of Symbols symbols should be given as a sequence eg. list Returns ======= A FiniteSet of ordered tuple of values of `symbols` for which the `system` has solution. Order of values in the tuple is same as symbols present in the parameter `symbols`. Please note that general FiniteSet is unordered, the solution returned here is not simply a FiniteSet of solutions, rather it is a FiniteSet of ordered tuple, i.e. the first & only argument to FiniteSet is a tuple of solutions, which is ordered, & hence the returned solution is ordered. Also note that solution could also have been returned as an ordered tuple, FiniteSet is just a wrapper `{}` around the tuple. It has no other significance except for the fact it is just used to maintain a consistent output format throughout the solveset. For the given set of Equations, the respective input types are given below: .. math:: x*y - 1 = 0 .. math:: 4*x**2 + y**2 - 5 = 0 `system = [x*y - 1, 4*x**2 + y**2 - 5]` `symbols = [x, y]` Raises ====== ValueError The input is not valid. The symbols are not given. AttributeError The input symbols are not `Symbol` type. Examples ======== >>> from sympy.core.symbol import symbols >>> from sympy.solvers.solveset import nonlinsolve >>> x, y, z = symbols('x, y, z', real=True) >>> nonlinsolve([x*y - 1, 4*x**2 + y**2 - 5], [x, y]) FiniteSet((-1, -1), (-1/2, -2), (1/2, 2), (1, 1)) 1. Positive dimensional system and complements: >>> from sympy import pprint >>> from sympy.polys.polytools import is_zero_dimensional >>> a, b, c, d = symbols('a, b, c, d', extended_real=True) >>> eq1 = a + b + c + d >>> eq2 = a*b + b*c + c*d + d*a >>> eq3 = a*b*c + b*c*d + c*d*a + d*a*b >>> eq4 = a*b*c*d - 1 >>> system = [eq1, eq2, eq3, eq4] >>> is_zero_dimensional(system) False >>> pprint(nonlinsolve(system, [a, b, c, d]), use_unicode=False) -1 1 1 -1 {(---, -d, -, {d} \ {0}), (-, -d, ---, {d} \ {0})} d d d d >>> nonlinsolve([(x+y)**2 - 4, x + y - 2], [x, y]) FiniteSet((2 - y, y)) 2. If some of the equations are non-polynomial then `nonlinsolve` will call the `substitution` function and return real and complex solutions, if present. >>> from sympy import exp, sin >>> nonlinsolve([exp(x) - sin(y), y**2 - 4], [x, y]) FiniteSet((ImageSet(Lambda(_n, 2*_n*I*pi + log(sin(2))), Integers), 2), (ImageSet(Lambda(_n, I*(2*_n*pi + pi) + log(sin(2))), Integers), -2)) 3. If system is non-linear polynomial and zero-dimensional then it returns both solution (real and complex solutions, if present) using `solve_poly_system`: >>> from sympy import sqrt >>> nonlinsolve([x**2 - 2*y**2 -2, x*y - 2], [x, y]) FiniteSet((-2, -1), (2, 1), (-sqrt(2)*I, sqrt(2)*I), (sqrt(2)*I, -sqrt(2)*I)) 4. `nonlinsolve` can solve some linear (zero or positive dimensional) system (because it uses the `groebner` function to get the groebner basis and then uses the `substitution` function basis as the new `system`). But it is not recommended to solve linear system using `nonlinsolve`, because `linsolve` is better for general linear systems. >>> nonlinsolve([x + 2*y -z - 3, x - y - 4*z + 9 , y + z - 4], [x, y, z]) FiniteSet((3*z - 5, 4 - z, z)) 5. System having polynomial equations and only real solution is solved using `solve_poly_system`: >>> e1 = sqrt(x**2 + y**2) - 10 >>> e2 = sqrt(y**2 + (-x + 10)**2) - 3 >>> nonlinsolve((e1, e2), (x, y)) FiniteSet((191/20, -3*sqrt(391)/20), (191/20, 3*sqrt(391)/20)) >>> nonlinsolve([x**2 + 2/y - 2, x + y - 3], [x, y]) FiniteSet((1, 2), (1 - sqrt(5), 2 + sqrt(5)), (1 + sqrt(5), 2 - sqrt(5))) >>> nonlinsolve([x**2 + 2/y - 2, x + y - 3], [y, x]) FiniteSet((2, 1), (2 - sqrt(5), 1 + sqrt(5)), (2 + sqrt(5), 1 - sqrt(5))) 6. It is better to use symbols instead of Trigonometric Function or Function (e.g. replace `sin(x)` with symbol, replace `f(x)` with symbol and so on. Get soln from `nonlinsolve` and then using `solveset` get the value of `x`) How nonlinsolve is better than old solver `_solve_system` : =========================================================== 1. A positive dimensional system solver : nonlinsolve can return solution for positive dimensional system. It finds the Groebner Basis of the positive dimensional system(calling it as basis) then we can start solving equation(having least number of variable first in the basis) using solveset and substituting that solved solutions into other equation(of basis) to get solution in terms of minimum variables. Here the important thing is how we are substituting the known values and in which equations. 2. Real and Complex both solutions : nonlinsolve returns both real and complex solution. If all the equations in the system are polynomial then using `solve_poly_system` both real and complex solution is returned. If all the equations in the system are not polynomial equation then goes to `substitution` method with this polynomial and non polynomial equation(s), to solve for unsolved variables. Here to solve for particular variable solveset_real and solveset_complex is used. For both real and complex solution function `_solve_using_know_values` is used inside `substitution` function.(`substitution` function will be called when there is any non polynomial equation(s) is present). When solution is valid then add its general solution in the final result. 3. Complement and Intersection will be added if any : nonlinsolve maintains dict for complements and Intersections. If solveset find complements or/and Intersection with any Interval or set during the execution of `substitution` function ,then complement or/and Intersection for that variable is added before returning final solution. """ from sympy.polys.polytools import is_zero_dimensional if not system: return S.EmptySet if not symbols: msg = ('Symbols must be given, for which solution of the ' 'system is to be found.') raise ValueError(filldedent(msg)) if hasattr(symbols[0], '__iter__'): symbols = symbols[0] if not is_sequence(symbols) or not symbols: msg = ('Symbols must be given, for which solution of the ' 'system is to be found.') raise IndexError(filldedent(msg)) system, symbols, swap = recast_to_symbols(system, symbols) if swap: soln = nonlinsolve(system, symbols) return FiniteSet(*[tuple(i.xreplace(swap) for i in s) for s in soln]) if len(system) == 1 and len(symbols) == 1: return _solveset_work(system, symbols) # main code of def nonlinsolve() starts from here polys, polys_expr, nonpolys, denominators = _separate_poly_nonpoly( system, symbols) if len(symbols) == len(polys): # If all the equations in the system are poly if is_zero_dimensional(polys, symbols): # finite number of soln (Zero dimensional system) try: return _handle_zero_dimensional(polys, symbols, system) except NotImplementedError: # Right now it doesn't fail for any polynomial system of # equation. If `solve_poly_system` fails then `substitution` # method will handle it. result = substitution( polys_expr, symbols, exclude=denominators) return result # positive dimensional system res = _handle_positive_dimensional(polys, symbols, denominators) if res is EmptySet and any(not p.domain.is_Exact for p in polys): raise NotImplementedError("Equation not in exact domain. Try converting to rational") else: return res else: # If all the equations are not polynomial. # Use `substitution` method for the system result = substitution( polys_expr + nonpolys, symbols, exclude=denominators) return result
367ebca63092bed017eba4f229449513aefb62ad0e121c5def5ad1c326cda55e
from sympy import ( symbols, sin, simplify, cos, trigsimp, tan, exptrigsimp,sinh, cosh, diff, cot, Subs, exp, tanh, S, integrate, I,Matrix, Symbol, coth, pi, log, count_ops, sqrt, E, expand, Piecewise , Rational ) from sympy.testing.pytest import XFAIL from sympy.abc import x, y def test_trigsimp1(): x, y = symbols('x,y') assert trigsimp(1 - sin(x)**2) == cos(x)**2 assert trigsimp(1 - cos(x)**2) == sin(x)**2 assert trigsimp(sin(x)**2 + cos(x)**2) == 1 assert trigsimp(1 + tan(x)**2) == 1/cos(x)**2 assert trigsimp(1/cos(x)**2 - 1) == tan(x)**2 assert trigsimp(1/cos(x)**2 - tan(x)**2) == 1 assert trigsimp(1 + cot(x)**2) == 1/sin(x)**2 assert trigsimp(1/sin(x)**2 - 1) == 1/tan(x)**2 assert trigsimp(1/sin(x)**2 - cot(x)**2) == 1 assert trigsimp(5*cos(x)**2 + 5*sin(x)**2) == 5 assert trigsimp(5*cos(x/2)**2 + 2*sin(x/2)**2) == 3*cos(x)/2 + Rational(7, 2) assert trigsimp(sin(x)/cos(x)) == tan(x) assert trigsimp(2*tan(x)*cos(x)) == 2*sin(x) assert trigsimp(cot(x)**3*sin(x)**3) == cos(x)**3 assert trigsimp(y*tan(x)**2/sin(x)**2) == y/cos(x)**2 assert trigsimp(cot(x)/cos(x)) == 1/sin(x) assert trigsimp(sin(x + y) + sin(x - y)) == 2*sin(x)*cos(y) assert trigsimp(sin(x + y) - sin(x - y)) == 2*sin(y)*cos(x) assert trigsimp(cos(x + y) + cos(x - y)) == 2*cos(x)*cos(y) assert trigsimp(cos(x + y) - cos(x - y)) == -2*sin(x)*sin(y) assert trigsimp(tan(x + y) - tan(x)/(1 - tan(x)*tan(y))) == \ sin(y)/(-sin(y)*tan(x) + cos(y)) # -tan(y)/(tan(x)*tan(y) - 1) assert trigsimp(sinh(x + y) + sinh(x - y)) == 2*sinh(x)*cosh(y) assert trigsimp(sinh(x + y) - sinh(x - y)) == 2*sinh(y)*cosh(x) assert trigsimp(cosh(x + y) + cosh(x - y)) == 2*cosh(x)*cosh(y) assert trigsimp(cosh(x + y) - cosh(x - y)) == 2*sinh(x)*sinh(y) assert trigsimp(tanh(x + y) - tanh(x)/(1 + tanh(x)*tanh(y))) == \ sinh(y)/(sinh(y)*tanh(x) + cosh(y)) assert trigsimp(cos(0.12345)**2 + sin(0.12345)**2) == 1 e = 2*sin(x)**2 + 2*cos(x)**2 assert trigsimp(log(e)) == log(2) def test_trigsimp1a(): assert trigsimp(sin(2)**2*cos(3)*exp(2)/cos(2)**2) == tan(2)**2*cos(3)*exp(2) assert trigsimp(tan(2)**2*cos(3)*exp(2)*cos(2)**2) == sin(2)**2*cos(3)*exp(2) assert trigsimp(cot(2)*cos(3)*exp(2)*sin(2)) == cos(3)*exp(2)*cos(2) assert trigsimp(tan(2)*cos(3)*exp(2)/sin(2)) == cos(3)*exp(2)/cos(2) assert trigsimp(cot(2)*cos(3)*exp(2)/cos(2)) == cos(3)*exp(2)/sin(2) assert trigsimp(cot(2)*cos(3)*exp(2)*tan(2)) == cos(3)*exp(2) assert trigsimp(sinh(2)*cos(3)*exp(2)/cosh(2)) == tanh(2)*cos(3)*exp(2) assert trigsimp(tanh(2)*cos(3)*exp(2)*cosh(2)) == sinh(2)*cos(3)*exp(2) assert trigsimp(coth(2)*cos(3)*exp(2)*sinh(2)) == cosh(2)*cos(3)*exp(2) assert trigsimp(tanh(2)*cos(3)*exp(2)/sinh(2)) == cos(3)*exp(2)/cosh(2) assert trigsimp(coth(2)*cos(3)*exp(2)/cosh(2)) == cos(3)*exp(2)/sinh(2) assert trigsimp(coth(2)*cos(3)*exp(2)*tanh(2)) == cos(3)*exp(2) def test_trigsimp2(): x, y = symbols('x,y') assert trigsimp(cos(x)**2*sin(y)**2 + cos(x)**2*cos(y)**2 + sin(x)**2, recursive=True) == 1 assert trigsimp(sin(x)**2*sin(y)**2 + sin(x)**2*cos(y)**2 + cos(x)**2, recursive=True) == 1 assert trigsimp( Subs(x, x, sin(y)**2 + cos(y)**2)) == Subs(x, x, 1) def test_issue_4373(): x = Symbol("x") assert abs(trigsimp(2.0*sin(x)**2 + 2.0*cos(x)**2) - 2.0) < 1e-10 def test_trigsimp3(): x, y = symbols('x,y') assert trigsimp(sin(x)/cos(x)) == tan(x) assert trigsimp(sin(x)**2/cos(x)**2) == tan(x)**2 assert trigsimp(sin(x)**3/cos(x)**3) == tan(x)**3 assert trigsimp(sin(x)**10/cos(x)**10) == tan(x)**10 assert trigsimp(cos(x)/sin(x)) == 1/tan(x) assert trigsimp(cos(x)**2/sin(x)**2) == 1/tan(x)**2 assert trigsimp(cos(x)**10/sin(x)**10) == 1/tan(x)**10 assert trigsimp(tan(x)) == trigsimp(sin(x)/cos(x)) def test_issue_4661(): a, x, y = symbols('a x y') eq = -4*sin(x)**4 + 4*cos(x)**4 - 8*cos(x)**2 assert trigsimp(eq) == -4 n = sin(x)**6 + 4*sin(x)**4*cos(x)**2 + 5*sin(x)**2*cos(x)**4 + 2*cos(x)**6 d = -sin(x)**2 - 2*cos(x)**2 assert simplify(n/d) == -1 assert trigsimp(-2*cos(x)**2 + cos(x)**4 - sin(x)**4) == -1 eq = (- sin(x)**3/4)*cos(x) + (cos(x)**3/4)*sin(x) - sin(2*x)*cos(2*x)/8 assert trigsimp(eq) == 0 def test_issue_4494(): a, b = symbols('a b') eq = sin(a)**2*sin(b)**2 + cos(a)**2*cos(b)**2*tan(a)**2 + cos(a)**2 assert trigsimp(eq) == 1 def test_issue_5948(): a, x, y = symbols('a x y') assert trigsimp(diff(integrate(cos(x)/sin(x)**7, x), x)) == \ cos(x)/sin(x)**7 def test_issue_4775(): a, x, y = symbols('a x y') assert trigsimp(sin(x)*cos(y)+cos(x)*sin(y)) == sin(x + y) assert trigsimp(sin(x)*cos(y)+cos(x)*sin(y)+3) == sin(x + y) + 3 def test_issue_4280(): a, x, y = symbols('a x y') assert trigsimp(cos(x)**2 + cos(y)**2*sin(x)**2 + sin(y)**2*sin(x)**2) == 1 assert trigsimp(a**2*sin(x)**2 + a**2*cos(y)**2*cos(x)**2 + a**2*cos(x)**2*sin(y)**2) == a**2 assert trigsimp(a**2*cos(y)**2*sin(x)**2 + a**2*sin(y)**2*sin(x)**2) == a**2*sin(x)**2 def test_issue_3210(): eqs = (sin(2)*cos(3) + sin(3)*cos(2), -sin(2)*sin(3) + cos(2)*cos(3), sin(2)*cos(3) - sin(3)*cos(2), sin(2)*sin(3) + cos(2)*cos(3), sin(2)*sin(3) + cos(2)*cos(3) + cos(2), sinh(2)*cosh(3) + sinh(3)*cosh(2), sinh(2)*sinh(3) + cosh(2)*cosh(3), ) assert [trigsimp(e) for e in eqs] == [ sin(5), cos(5), -sin(1), cos(1), cos(1) + cos(2), sinh(5), cosh(5), ] def test_trigsimp_issues(): a, x, y = symbols('a x y') # issue 4625 - factor_terms works, too assert trigsimp(sin(x)**3 + cos(x)**2*sin(x)) == sin(x) # issue 5948 assert trigsimp(diff(integrate(cos(x)/sin(x)**3, x), x)) == \ cos(x)/sin(x)**3 assert trigsimp(diff(integrate(sin(x)/cos(x)**3, x), x)) == \ sin(x)/cos(x)**3 # check integer exponents e = sin(x)**y/cos(x)**y assert trigsimp(e) == e assert trigsimp(e.subs(y, 2)) == tan(x)**2 assert trigsimp(e.subs(x, 1)) == tan(1)**y # check for multiple patterns assert (cos(x)**2/sin(x)**2*cos(y)**2/sin(y)**2).trigsimp() == \ 1/tan(x)**2/tan(y)**2 assert trigsimp(cos(x)/sin(x)*cos(x+y)/sin(x+y)) == \ 1/(tan(x)*tan(x + y)) eq = cos(2)*(cos(3) + 1)**2/(cos(3) - 1)**2 assert trigsimp(eq) == eq.factor() # factor makes denom (-1 + cos(3))**2 assert trigsimp(cos(2)*(cos(3) + 1)**2*(cos(3) - 1)**2) == \ cos(2)*sin(3)**4 # issue 6789; this generates an expression that formerly caused # trigsimp to hang assert cot(x).equals(tan(x)) is False # nan or the unchanged expression is ok, but not sin(1) z = cos(x)**2 + sin(x)**2 - 1 z1 = tan(x)**2 - 1/cot(x)**2 n = (1 + z1/z) assert trigsimp(sin(n)) != sin(1) eq = x*(n - 1) - x*n assert trigsimp(eq) is S.NaN assert trigsimp(eq, recursive=True) is S.NaN assert trigsimp(1).is_Integer assert trigsimp(-sin(x)**4 - 2*sin(x)**2*cos(x)**2 - cos(x)**4) == -1 def test_trigsimp_issue_2515(): x = Symbol('x') assert trigsimp(x*cos(x)*tan(x)) == x*sin(x) assert trigsimp(-sin(x) + cos(x)*tan(x)) == 0 def test_trigsimp_issue_3826(): assert trigsimp(tan(2*x).expand(trig=True)) == tan(2*x) def test_trigsimp_issue_4032(): n = Symbol('n', integer=True, positive=True) assert trigsimp(2**(n/2)*cos(pi*n/4)/2 + 2**(n - 1)/2) == \ 2**(n/2)*cos(pi*n/4)/2 + 2**n/4 def test_trigsimp_issue_7761(): assert trigsimp(cosh(pi/4)) == cosh(pi/4) def test_trigsimp_noncommutative(): x, y = symbols('x,y') A, B = symbols('A,B', commutative=False) assert trigsimp(A - A*sin(x)**2) == A*cos(x)**2 assert trigsimp(A - A*cos(x)**2) == A*sin(x)**2 assert trigsimp(A*sin(x)**2 + A*cos(x)**2) == A assert trigsimp(A + A*tan(x)**2) == A/cos(x)**2 assert trigsimp(A/cos(x)**2 - A) == A*tan(x)**2 assert trigsimp(A/cos(x)**2 - A*tan(x)**2) == A assert trigsimp(A + A*cot(x)**2) == A/sin(x)**2 assert trigsimp(A/sin(x)**2 - A) == A/tan(x)**2 assert trigsimp(A/sin(x)**2 - A*cot(x)**2) == A assert trigsimp(y*A*cos(x)**2 + y*A*sin(x)**2) == y*A assert trigsimp(A*sin(x)/cos(x)) == A*tan(x) assert trigsimp(A*tan(x)*cos(x)) == A*sin(x) assert trigsimp(A*cot(x)**3*sin(x)**3) == A*cos(x)**3 assert trigsimp(y*A*tan(x)**2/sin(x)**2) == y*A/cos(x)**2 assert trigsimp(A*cot(x)/cos(x)) == A/sin(x) assert trigsimp(A*sin(x + y) + A*sin(x - y)) == 2*A*sin(x)*cos(y) assert trigsimp(A*sin(x + y) - A*sin(x - y)) == 2*A*sin(y)*cos(x) assert trigsimp(A*cos(x + y) + A*cos(x - y)) == 2*A*cos(x)*cos(y) assert trigsimp(A*cos(x + y) - A*cos(x - y)) == -2*A*sin(x)*sin(y) assert trigsimp(A*sinh(x + y) + A*sinh(x - y)) == 2*A*sinh(x)*cosh(y) assert trigsimp(A*sinh(x + y) - A*sinh(x - y)) == 2*A*sinh(y)*cosh(x) assert trigsimp(A*cosh(x + y) + A*cosh(x - y)) == 2*A*cosh(x)*cosh(y) assert trigsimp(A*cosh(x + y) - A*cosh(x - y)) == 2*A*sinh(x)*sinh(y) assert trigsimp(A*cos(0.12345)**2 + A*sin(0.12345)**2) == 1.0*A def test_hyperbolic_simp(): x, y = symbols('x,y') assert trigsimp(sinh(x)**2 + 1) == cosh(x)**2 assert trigsimp(cosh(x)**2 - 1) == sinh(x)**2 assert trigsimp(cosh(x)**2 - sinh(x)**2) == 1 assert trigsimp(1 - tanh(x)**2) == 1/cosh(x)**2 assert trigsimp(1 - 1/cosh(x)**2) == tanh(x)**2 assert trigsimp(tanh(x)**2 + 1/cosh(x)**2) == 1 assert trigsimp(coth(x)**2 - 1) == 1/sinh(x)**2 assert trigsimp(1/sinh(x)**2 + 1) == 1/tanh(x)**2 assert trigsimp(coth(x)**2 - 1/sinh(x)**2) == 1 assert trigsimp(5*cosh(x)**2 - 5*sinh(x)**2) == 5 assert trigsimp(5*cosh(x/2)**2 - 2*sinh(x/2)**2) == 3*cosh(x)/2 + Rational(7, 2) assert trigsimp(sinh(x)/cosh(x)) == tanh(x) assert trigsimp(tanh(x)) == trigsimp(sinh(x)/cosh(x)) assert trigsimp(cosh(x)/sinh(x)) == 1/tanh(x) assert trigsimp(2*tanh(x)*cosh(x)) == 2*sinh(x) assert trigsimp(coth(x)**3*sinh(x)**3) == cosh(x)**3 assert trigsimp(y*tanh(x)**2/sinh(x)**2) == y/cosh(x)**2 assert trigsimp(coth(x)/cosh(x)) == 1/sinh(x) for a in (pi/6*I, pi/4*I, pi/3*I): assert trigsimp(sinh(a)*cosh(x) + cosh(a)*sinh(x)) == sinh(x + a) assert trigsimp(-sinh(a)*cosh(x) + cosh(a)*sinh(x)) == sinh(x - a) e = 2*cosh(x)**2 - 2*sinh(x)**2 assert trigsimp(log(e)) == log(2) # issue 19535: assert trigsimp(sqrt(cosh(x)**2 - 1)) == sqrt(sinh(x)**2) assert trigsimp(cosh(x)**2*cosh(y)**2 - cosh(x)**2*sinh(y)**2 - sinh(x)**2, recursive=True) == 1 assert trigsimp(sinh(x)**2*sinh(y)**2 - sinh(x)**2*cosh(y)**2 + cosh(x)**2, recursive=True) == 1 assert abs(trigsimp(2.0*cosh(x)**2 - 2.0*sinh(x)**2) - 2.0) < 1e-10 assert trigsimp(sinh(x)**2/cosh(x)**2) == tanh(x)**2 assert trigsimp(sinh(x)**3/cosh(x)**3) == tanh(x)**3 assert trigsimp(sinh(x)**10/cosh(x)**10) == tanh(x)**10 assert trigsimp(cosh(x)**3/sinh(x)**3) == 1/tanh(x)**3 assert trigsimp(cosh(x)/sinh(x)) == 1/tanh(x) assert trigsimp(cosh(x)**2/sinh(x)**2) == 1/tanh(x)**2 assert trigsimp(cosh(x)**10/sinh(x)**10) == 1/tanh(x)**10 assert trigsimp(x*cosh(x)*tanh(x)) == x*sinh(x) assert trigsimp(-sinh(x) + cosh(x)*tanh(x)) == 0 assert tan(x) != 1/cot(x) # cot doesn't auto-simplify assert trigsimp(tan(x) - 1/cot(x)) == 0 assert trigsimp(3*tanh(x)**7 - 2/coth(x)**7) == tanh(x)**7 def test_trigsimp_groebner(): from sympy.simplify.trigsimp import trigsimp_groebner c = cos(x) s = sin(x) ex = (4*s*c + 12*s + 5*c**3 + 21*c**2 + 23*c + 15)/( -s*c**2 + 2*s*c + 15*s + 7*c**3 + 31*c**2 + 37*c + 21) resnum = (5*s - 5*c + 1) resdenom = (8*s - 6*c) results = [resnum/resdenom, (-resnum)/(-resdenom)] assert trigsimp_groebner(ex) in results assert trigsimp_groebner(s/c, hints=[tan]) == tan(x) assert trigsimp_groebner(c*s) == c*s assert trigsimp((-s + 1)/c + c/(-s + 1), method='groebner') == 2/c assert trigsimp((-s + 1)/c + c/(-s + 1), method='groebner', polynomial=True) == 2/c # Test quick=False works assert trigsimp_groebner(ex, hints=[2]) in results assert trigsimp_groebner(ex, hints=[int(2)]) in results # test "I" assert trigsimp_groebner(sin(I*x)/cos(I*x), hints=[tanh]) == I*tanh(x) # test hyperbolic / sums assert trigsimp_groebner((tanh(x)+tanh(y))/(1+tanh(x)*tanh(y)), hints=[(tanh, x, y)]) == tanh(x + y) def test_issue_2827_trigsimp_methods(): measure1 = lambda expr: len(str(expr)) measure2 = lambda expr: -count_ops(expr) # Return the most complicated result expr = (x + 1)/(x + sin(x)**2 + cos(x)**2) ans = Matrix([1]) M = Matrix([expr]) assert trigsimp(M, method='fu', measure=measure1) == ans assert trigsimp(M, method='fu', measure=measure2) != ans # all methods should work with Basic expressions even if they # aren't Expr M = Matrix.eye(1) assert all(trigsimp(M, method=m) == M for m in 'fu matching groebner old'.split()) # watch for E in exptrigsimp, not only exp() eq = 1/sqrt(E) + E assert exptrigsimp(eq) == eq def test_issue_15129_trigsimp_methods(): t1 = Matrix([sin(Rational(1, 50)), cos(Rational(1, 50)), 0]) t2 = Matrix([sin(Rational(1, 25)), cos(Rational(1, 25)), 0]) t3 = Matrix([cos(Rational(1, 25)), sin(Rational(1, 25)), 0]) r1 = t1.dot(t2) r2 = t1.dot(t3) assert trigsimp(r1) == cos(Rational(1, 50)) assert trigsimp(r2) == sin(Rational(3, 50)) def test_exptrigsimp(): def valid(a, b): from sympy.testing.randtest import verify_numerically as tn if not (tn(a, b) and a == b): return False return True assert exptrigsimp(exp(x) + exp(-x)) == 2*cosh(x) assert exptrigsimp(exp(x) - exp(-x)) == 2*sinh(x) assert exptrigsimp((2*exp(x)-2*exp(-x))/(exp(x)+exp(-x))) == 2*tanh(x) assert exptrigsimp((2*exp(2*x)-2)/(exp(2*x)+1)) == 2*tanh(x) e = [cos(x) + I*sin(x), cos(x) - I*sin(x), cosh(x) - sinh(x), cosh(x) + sinh(x)] ok = [exp(I*x), exp(-I*x), exp(-x), exp(x)] assert all(valid(i, j) for i, j in zip( [exptrigsimp(ei) for ei in e], ok)) ue = [cos(x) + sin(x), cos(x) - sin(x), cosh(x) + I*sinh(x), cosh(x) - I*sinh(x)] assert [exptrigsimp(ei) == ei for ei in ue] res = [] ok = [y*tanh(1), 1/(y*tanh(1)), I*y*tan(1), -I/(y*tan(1)), y*tanh(x), 1/(y*tanh(x)), I*y*tan(x), -I/(y*tan(x)), y*tanh(1 + I), 1/(y*tanh(1 + I))] for a in (1, I, x, I*x, 1 + I): w = exp(a) eq = y*(w - 1/w)/(w + 1/w) res.append(simplify(eq)) res.append(simplify(1/eq)) assert all(valid(i, j) for i, j in zip(res, ok)) for a in range(1, 3): w = exp(a) e = w + 1/w s = simplify(e) assert s == exptrigsimp(e) assert valid(s, 2*cosh(a)) e = w - 1/w s = simplify(e) assert s == exptrigsimp(e) assert valid(s, 2*sinh(a)) def test_exptrigsimp_noncommutative(): a,b = symbols('a b', commutative=False) x = Symbol('x', commutative=True) assert exp(a + x) == exptrigsimp(exp(a)*exp(x)) p = exp(a)*exp(b) - exp(b)*exp(a) assert p == exptrigsimp(p) != 0 def test_powsimp_on_numbers(): assert 2**(Rational(1, 3) - 2) == 2**Rational(1, 3)/4 @XFAIL def test_issue_6811_fail(): # from doc/src/modules/physics/mechanics/examples.rst, the current `eq` # at Line 576 (in different variables) was formerly the equivalent and # shorter expression given below...it would be nice to get the short one # back again xp, y, x, z = symbols('xp, y, x, z') eq = 4*(-19*sin(x)*y + 5*sin(3*x)*y + 15*cos(2*x)*z - 21*z)*xp/(9*cos(x) - 5*cos(3*x)) assert trigsimp(eq) == -2*(2*cos(x)*tan(x)*y + 3*z)*xp/cos(x) def test_Piecewise(): e1 = x*(x + y) - y*(x + y) e2 = sin(x)**2 + cos(x)**2 e3 = expand((x + y)*y/x) # s1 = simplify(e1) s2 = simplify(e2) # s3 = simplify(e3) # trigsimp tries not to touch non-trig containing args assert trigsimp(Piecewise((e1, e3 < e2), (e3, True))) == \ Piecewise((e1, e3 < s2), (e3, True)) def test_issue_21594(): assert simplify(exp(Rational(1,2)) + exp(Rational(-1,2))) == cosh(S.Half)*2 def test_trigsimp_old(): x, y = symbols('x,y') assert trigsimp(1 - sin(x)**2, old=True) == cos(x)**2 assert trigsimp(1 - cos(x)**2, old=True) == sin(x)**2 assert trigsimp(sin(x)**2 + cos(x)**2, old=True) == 1 assert trigsimp(1 + tan(x)**2, old=True) == 1/cos(x)**2 assert trigsimp(1/cos(x)**2 - 1, old=True) == tan(x)**2 assert trigsimp(1/cos(x)**2 - tan(x)**2, old=True) == 1 assert trigsimp(1 + cot(x)**2, old=True) == 1/sin(x)**2 assert trigsimp(1/sin(x)**2 - cot(x)**2, old=True) == 1 assert trigsimp(5*cos(x)**2 + 5*sin(x)**2, old=True) == 5 assert trigsimp(sin(x)/cos(x), old=True) == tan(x) assert trigsimp(2*tan(x)*cos(x), old=True) == 2*sin(x) assert trigsimp(cot(x)**3*sin(x)**3, old=True) == cos(x)**3 assert trigsimp(y*tan(x)**2/sin(x)**2, old=True) == y/cos(x)**2 assert trigsimp(cot(x)/cos(x), old=True) == 1/sin(x) assert trigsimp(sin(x + y) + sin(x - y), old=True) == 2*sin(x)*cos(y) assert trigsimp(sin(x + y) - sin(x - y), old=True) == 2*sin(y)*cos(x) assert trigsimp(cos(x + y) + cos(x - y), old=True) == 2*cos(x)*cos(y) assert trigsimp(cos(x + y) - cos(x - y), old=True) == -2*sin(x)*sin(y) assert trigsimp(sinh(x + y) + sinh(x - y), old=True) == 2*sinh(x)*cosh(y) assert trigsimp(sinh(x + y) - sinh(x - y), old=True) == 2*sinh(y)*cosh(x) assert trigsimp(cosh(x + y) + cosh(x - y), old=True) == 2*cosh(x)*cosh(y) assert trigsimp(cosh(x + y) - cosh(x - y), old=True) == 2*sinh(x)*sinh(y) assert trigsimp(cos(0.12345)**2 + sin(0.12345)**2, old=True) == 1 assert trigsimp(sin(x)/cos(x), old=True, method='combined') == tan(x) assert trigsimp(sin(x)/cos(x), old=True, method='groebner') == sin(x)/cos(x) assert trigsimp(sin(x)/cos(x), old=True, method='groebner', hints=[tan]) == tan(x) assert trigsimp(1-sin(sin(x)**2+cos(x)**2)**2, old=True, deep=True) == cos(1)**2
d37ee7eeb90293403084712889bcde2d579c6069ddbac0707f2f9a776c8e2a82
r""" This module contains :py:meth:`~sympy.solvers.ode.dsolve` and different helper functions that it uses. :py:meth:`~sympy.solvers.ode.dsolve` solves ordinary differential equations. See the docstring on the various functions for their uses. Note that partial differential equations support is in ``pde.py``. Note that hint functions have docstrings describing their various methods, but they are intended for internal use. Use ``dsolve(ode, func, hint=hint)`` to solve an ODE using a specific hint. See also the docstring on :py:meth:`~sympy.solvers.ode.dsolve`. **Functions in this module** These are the user functions in this module: - :py:meth:`~sympy.solvers.ode.dsolve` - Solves ODEs. - :py:meth:`~sympy.solvers.ode.classify_ode` - Classifies ODEs into possible hints for :py:meth:`~sympy.solvers.ode.dsolve`. - :py:meth:`~sympy.solvers.ode.checkodesol` - Checks if an equation is the solution to an ODE. - :py:meth:`~sympy.solvers.ode.homogeneous_order` - Returns the homogeneous order of an expression. - :py:meth:`~sympy.solvers.ode.infinitesimals` - Returns the infinitesimals of the Lie group of point transformations of an ODE, such that it is invariant. - :py:meth:`~sympy.solvers.ode.checkinfsol` - Checks if the given infinitesimals are the actual infinitesimals of a first order ODE. These are the non-solver helper functions that are for internal use. The user should use the various options to :py:meth:`~sympy.solvers.ode.dsolve` to obtain the functionality provided by these functions: - :py:meth:`~sympy.solvers.ode.ode.odesimp` - Does all forms of ODE simplification. - :py:meth:`~sympy.solvers.ode.ode.ode_sol_simplicity` - A key function for comparing solutions by simplicity. - :py:meth:`~sympy.solvers.ode.constantsimp` - Simplifies arbitrary constants. - :py:meth:`~sympy.solvers.ode.ode.constant_renumber` - Renumber arbitrary constants. - :py:meth:`~sympy.solvers.ode.ode._handle_Integral` - Evaluate unevaluated Integrals. See also the docstrings of these functions. **Currently implemented solver methods** The following methods are implemented for solving ordinary differential equations. See the docstrings of the various hint functions for more information on each (run ``help(ode)``): - 1st order separable differential equations. - 1st order differential equations whose coefficients or `dx` and `dy` are functions homogeneous of the same order. - 1st order exact differential equations. - 1st order linear differential equations. - 1st order Bernoulli differential equations. - Power series solutions for first order differential equations. - Lie Group method of solving first order differential equations. - 2nd order Liouville differential equations. - Power series solutions for second order differential equations at ordinary and regular singular points. - `n`\th order differential equation that can be solved with algebraic rearrangement and integration. - `n`\th order linear homogeneous differential equation with constant coefficients. - `n`\th order linear inhomogeneous differential equation with constant coefficients using the method of undetermined coefficients. - `n`\th order linear inhomogeneous differential equation with constant coefficients using the method of variation of parameters. **Philosophy behind this module** This module is designed to make it easy to add new ODE solving methods without having to mess with the solving code for other methods. The idea is that there is a :py:meth:`~sympy.solvers.ode.classify_ode` function, which takes in an ODE and tells you what hints, if any, will solve the ODE. It does this without attempting to solve the ODE, so it is fast. Each solving method is a hint, and it has its own function, named ``ode_<hint>``. That function takes in the ODE and any match expression gathered by :py:meth:`~sympy.solvers.ode.classify_ode` and returns a solved result. If this result has any integrals in it, the hint function will return an unevaluated :py:class:`~sympy.integrals.integrals.Integral` class. :py:meth:`~sympy.solvers.ode.dsolve`, which is the user wrapper function around all of this, will then call :py:meth:`~sympy.solvers.ode.ode.odesimp` on the result, which, among other things, will attempt to solve the equation for the dependent variable (the function we are solving for), simplify the arbitrary constants in the expression, and evaluate any integrals, if the hint allows it. **How to add new solution methods** If you have an ODE that you want :py:meth:`~sympy.solvers.ode.dsolve` to be able to solve, try to avoid adding special case code here. Instead, try finding a general method that will solve your ODE, as well as others. This way, the :py:mod:`~sympy.solvers.ode` module will become more robust, and unhindered by special case hacks. WolphramAlpha and Maple's DETools[odeadvisor] function are two resources you can use to classify a specific ODE. It is also better for a method to work with an `n`\th order ODE instead of only with specific orders, if possible. To add a new method, there are a few things that you need to do. First, you need a hint name for your method. Try to name your hint so that it is unambiguous with all other methods, including ones that may not be implemented yet. If your method uses integrals, also include a ``hint_Integral`` hint. If there is more than one way to solve ODEs with your method, include a hint for each one, as well as a ``<hint>_best`` hint. Your ``ode_<hint>_best()`` function should choose the best using min with ``ode_sol_simplicity`` as the key argument. See :obj:`~sympy.solvers.ode.single.HomogeneousCoeffBest`, for example. The function that uses your method will be called ``ode_<hint>()``, so the hint must only use characters that are allowed in a Python function name (alphanumeric characters and the underscore '``_``' character). Include a function for every hint, except for ``_Integral`` hints (:py:meth:`~sympy.solvers.ode.dsolve` takes care of those automatically). Hint names should be all lowercase, unless a word is commonly capitalized (such as Integral or Bernoulli). If you have a hint that you do not want to run with ``all_Integral`` that doesn't have an ``_Integral`` counterpart (such as a best hint that would defeat the purpose of ``all_Integral``), you will need to remove it manually in the :py:meth:`~sympy.solvers.ode.dsolve` code. See also the :py:meth:`~sympy.solvers.ode.classify_ode` docstring for guidelines on writing a hint name. Determine *in general* how the solutions returned by your method compare with other methods that can potentially solve the same ODEs. Then, put your hints in the :py:data:`~sympy.solvers.ode.allhints` tuple in the order that they should be called. The ordering of this tuple determines which hints are default. Note that exceptions are ok, because it is easy for the user to choose individual hints with :py:meth:`~sympy.solvers.ode.dsolve`. In general, ``_Integral`` variants should go at the end of the list, and ``_best`` variants should go before the various hints they apply to. For example, the ``undetermined_coefficients`` hint comes before the ``variation_of_parameters`` hint because, even though variation of parameters is more general than undetermined coefficients, undetermined coefficients generally returns cleaner results for the ODEs that it can solve than variation of parameters does, and it does not require integration, so it is much faster. Next, you need to have a match expression or a function that matches the type of the ODE, which you should put in :py:meth:`~sympy.solvers.ode.classify_ode` (if the match function is more than just a few lines, like :py:meth:`~sympy.solvers.ode.ode._undetermined_coefficients_match`, it should go outside of :py:meth:`~sympy.solvers.ode.classify_ode`). It should match the ODE without solving for it as much as possible, so that :py:meth:`~sympy.solvers.ode.classify_ode` remains fast and is not hindered by bugs in solving code. Be sure to consider corner cases. For example, if your solution method involves dividing by something, make sure you exclude the case where that division will be 0. In most cases, the matching of the ODE will also give you the various parts that you need to solve it. You should put that in a dictionary (``.match()`` will do this for you), and add that as ``matching_hints['hint'] = matchdict`` in the relevant part of :py:meth:`~sympy.solvers.ode.classify_ode`. :py:meth:`~sympy.solvers.ode.classify_ode` will then send this to :py:meth:`~sympy.solvers.ode.dsolve`, which will send it to your function as the ``match`` argument. Your function should be named ``ode_<hint>(eq, func, order, match)`. If you need to send more information, put it in the ``match`` dictionary. For example, if you had to substitute in a dummy variable in :py:meth:`~sympy.solvers.ode.classify_ode` to match the ODE, you will need to pass it to your function using the `match` dict to access it. You can access the independent variable using ``func.args[0]``, and the dependent variable (the function you are trying to solve for) as ``func.func``. If, while trying to solve the ODE, you find that you cannot, raise ``NotImplementedError``. :py:meth:`~sympy.solvers.ode.dsolve` will catch this error with the ``all`` meta-hint, rather than causing the whole routine to fail. Add a docstring to your function that describes the method employed. Like with anything else in SymPy, you will need to add a doctest to the docstring, in addition to real tests in ``test_ode.py``. Try to maintain consistency with the other hint functions' docstrings. Add your method to the list at the top of this docstring. Also, add your method to ``ode.rst`` in the ``docs/src`` directory, so that the Sphinx docs will pull its docstring into the main SymPy documentation. Be sure to make the Sphinx documentation by running ``make html`` from within the doc directory to verify that the docstring formats correctly. If your solution method involves integrating, use :py:obj:`~.Integral` instead of :py:meth:`~sympy.core.expr.Expr.integrate`. This allows the user to bypass hard/slow integration by using the ``_Integral`` variant of your hint. In most cases, calling :py:meth:`sympy.core.basic.Basic.doit` will integrate your solution. If this is not the case, you will need to write special code in :py:meth:`~sympy.solvers.ode.ode._handle_Integral`. Arbitrary constants should be symbols named ``C1``, ``C2``, and so on. All solution methods should return an equality instance. If you need an arbitrary number of arbitrary constants, you can use ``constants = numbered_symbols(prefix='C', cls=Symbol, start=1)``. If it is possible to solve for the dependent function in a general way, do so. Otherwise, do as best as you can, but do not call solve in your ``ode_<hint>()`` function. :py:meth:`~sympy.solvers.ode.ode.odesimp` will attempt to solve the solution for you, so you do not need to do that. Lastly, if your ODE has a common simplification that can be applied to your solutions, you can add a special case in :py:meth:`~sympy.solvers.ode.ode.odesimp` for it. For example, solutions returned from the ``1st_homogeneous_coeff`` hints often have many :obj:`~sympy.functions.elementary.exponential.log` terms, so :py:meth:`~sympy.solvers.ode.ode.odesimp` calls :py:meth:`~sympy.simplify.simplify.logcombine` on them (it also helps to write the arbitrary constant as ``log(C1)`` instead of ``C1`` in this case). Also consider common ways that you can rearrange your solution to have :py:meth:`~sympy.solvers.ode.constantsimp` take better advantage of it. It is better to put simplification in :py:meth:`~sympy.solvers.ode.ode.odesimp` than in your method, because it can then be turned off with the simplify flag in :py:meth:`~sympy.solvers.ode.dsolve`. If you have any extraneous simplification in your function, be sure to only run it using ``if match.get('simplify', True):``, especially if it can be slow or if it can reduce the domain of the solution. Finally, as with every contribution to SymPy, your method will need to be tested. Add a test for each method in ``test_ode.py``. Follow the conventions there, i.e., test the solver using ``dsolve(eq, f(x), hint=your_hint)``, and also test the solution using :py:meth:`~sympy.solvers.ode.checkodesol` (you can put these in a separate tests and skip/XFAIL if it runs too slow/doesn't work). Be sure to call your hint specifically in :py:meth:`~sympy.solvers.ode.dsolve`, that way the test won't be broken simply by the introduction of another matching hint. If your method works for higher order (>1) ODEs, you will need to run ``sol = constant_renumber(sol, 'C', 1, order)`` for each solution, where ``order`` is the order of the ODE. This is because ``constant_renumber`` renumbers the arbitrary constants by printing order, which is platform dependent. Try to test every corner case of your solver, including a range of orders if it is a `n`\th order solver, but if your solver is slow, such as if it involves hard integration, try to keep the test run time down. Feel free to refactor existing hints to avoid duplicating code or creating inconsistencies. If you can show that your method exactly duplicates an existing method, including in the simplicity and speed of obtaining the solutions, then you can remove the old, less general method. The existing code is tested extensively in ``test_ode.py``, so if anything is broken, one of those tests will surely fail. """ from collections import defaultdict from itertools import islice from sympy.functions import hyper from sympy.core import Add, S, Mul, Pow, oo, Rational from sympy.core.compatibility import ordered, iterable from sympy.core.containers import Tuple from sympy.core.exprtools import factor_terms from sympy.core.expr import AtomicExpr, Expr from sympy.core.function import (Function, Derivative, AppliedUndef, diff, expand, expand_mul, Subs, _mexpand) from sympy.core.multidimensional import vectorize from sympy.core.numbers import NaN, zoo, Number from sympy.core.relational import Equality, Eq from sympy.core.symbol import Symbol, Wild, Dummy, symbols from sympy.core.sympify import sympify from sympy.logic.boolalg import (BooleanAtom, BooleanTrue, BooleanFalse) from sympy.functions import cos, cosh, exp, im, log, re, sin, sinh, sqrt, \ atan2, conjugate, cbrt, besselj, bessely, airyai, airybi from sympy.functions.combinatorial.factorials import factorial from sympy.integrals.integrals import Integral, integrate from sympy.matrices import wronskian from sympy.polys import (Poly, RootOf, rootof, terms_gcd, PolynomialError, lcm, roots, gcd) from sympy.polys.polytools import cancel, degree, div from sympy.series import Order from sympy.series.series import series from sympy.simplify import (collect, logcombine, powsimp, # type: ignore separatevars, simplify, trigsimp, posify, cse) from sympy.simplify.powsimp import powdenest from sympy.simplify.radsimp import collect_const from sympy.solvers import checksol, solve from sympy.solvers.pde import pdsolve from sympy.utilities import numbered_symbols, default_sort_key, sift from sympy.utilities.iterables import uniq from sympy.solvers.deutils import _preprocess, ode_order, _desolve from .subscheck import sub_func_doit #: This is a list of hints in the order that they should be preferred by #: :py:meth:`~sympy.solvers.ode.classify_ode`. In general, hints earlier in the #: list should produce simpler solutions than those later in the list (for #: ODEs that fit both). For now, the order of this list is based on empirical #: observations by the developers of SymPy. #: #: The hint used by :py:meth:`~sympy.solvers.ode.dsolve` for a specific ODE #: can be overridden (see the docstring). #: #: In general, ``_Integral`` hints are grouped at the end of the list, unless #: there is a method that returns an unevaluable integral most of the time #: (which go near the end of the list anyway). ``default``, ``all``, #: ``best``, and ``all_Integral`` meta-hints should not be included in this #: list, but ``_best`` and ``_Integral`` hints should be included. allhints = ( "factorable", "nth_algebraic", "separable", "1st_exact", "1st_linear", "Bernoulli", "Riccati_special_minus2", "1st_homogeneous_coeff_best", "1st_homogeneous_coeff_subs_indep_div_dep", "1st_homogeneous_coeff_subs_dep_div_indep", "almost_linear", "linear_coefficients", "separable_reduced", "1st_power_series", "lie_group", "nth_linear_constant_coeff_homogeneous", "nth_linear_euler_eq_homogeneous", "nth_linear_constant_coeff_undetermined_coefficients", "nth_linear_euler_eq_nonhomogeneous_undetermined_coefficients", "nth_linear_constant_coeff_variation_of_parameters", "nth_linear_euler_eq_nonhomogeneous_variation_of_parameters", "Liouville", "2nd_linear_airy", "2nd_linear_bessel", "2nd_hypergeometric", "2nd_hypergeometric_Integral", "nth_order_reducible", "2nd_power_series_ordinary", "2nd_power_series_regular", "nth_algebraic_Integral", "separable_Integral", "1st_exact_Integral", "1st_linear_Integral", "Bernoulli_Integral", "1st_homogeneous_coeff_subs_indep_div_dep_Integral", "1st_homogeneous_coeff_subs_dep_div_indep_Integral", "almost_linear_Integral", "linear_coefficients_Integral", "separable_reduced_Integral", "nth_linear_constant_coeff_variation_of_parameters_Integral", "nth_linear_euler_eq_nonhomogeneous_variation_of_parameters_Integral", "Liouville_Integral", "2nd_nonlinear_autonomous_conserved", "2nd_nonlinear_autonomous_conserved_Integral", ) lie_heuristics = ( "abaco1_simple", "abaco1_product", "abaco2_similar", "abaco2_unique_unknown", "abaco2_unique_general", "linear", "function_sum", "bivariate", "chi" ) def get_numbered_constants(eq, num=1, start=1, prefix='C'): """ Returns a list of constants that do not occur in eq already. """ ncs = iter_numbered_constants(eq, start, prefix) Cs = [next(ncs) for i in range(num)] return (Cs[0] if num == 1 else tuple(Cs)) def iter_numbered_constants(eq, start=1, prefix='C'): """ Returns an iterator of constants that do not occur in eq already. """ if isinstance(eq, (Expr, Eq)): eq = [eq] elif not iterable(eq): raise ValueError("Expected Expr or iterable but got %s" % eq) atom_set = set().union(*[i.free_symbols for i in eq]) func_set = set().union(*[i.atoms(Function) for i in eq]) if func_set: atom_set |= {Symbol(str(f.func)) for f in func_set} return numbered_symbols(start=start, prefix=prefix, exclude=atom_set) def dsolve(eq, func=None, hint="default", simplify=True, ics= None, xi=None, eta=None, x0=0, n=6, **kwargs): r""" Solves any (supported) kind of ordinary differential equation and system of ordinary differential equations. For single ordinary differential equation ========================================= It is classified under this when number of equation in ``eq`` is one. **Usage** ``dsolve(eq, f(x), hint)`` -> Solve ordinary differential equation ``eq`` for function ``f(x)``, using method ``hint``. **Details** ``eq`` can be any supported ordinary differential equation (see the :py:mod:`~sympy.solvers.ode` docstring for supported methods). This can either be an :py:class:`~sympy.core.relational.Equality`, or an expression, which is assumed to be equal to ``0``. ``f(x)`` is a function of one variable whose derivatives in that variable make up the ordinary differential equation ``eq``. In many cases it is not necessary to provide this; it will be autodetected (and an error raised if it couldn't be detected). ``hint`` is the solving method that you want dsolve to use. Use ``classify_ode(eq, f(x))`` to get all of the possible hints for an ODE. The default hint, ``default``, will use whatever hint is returned first by :py:meth:`~sympy.solvers.ode.classify_ode`. See Hints below for more options that you can use for hint. ``simplify`` enables simplification by :py:meth:`~sympy.solvers.ode.ode.odesimp`. See its docstring for more information. Turn this off, for example, to disable solving of solutions for ``func`` or simplification of arbitrary constants. It will still integrate with this hint. Note that the solution may contain more arbitrary constants than the order of the ODE with this option enabled. ``xi`` and ``eta`` are the infinitesimal functions of an ordinary differential equation. They are the infinitesimals of the Lie group of point transformations for which the differential equation is invariant. The user can specify values for the infinitesimals. If nothing is specified, ``xi`` and ``eta`` are calculated using :py:meth:`~sympy.solvers.ode.infinitesimals` with the help of various heuristics. ``ics`` is the set of initial/boundary conditions for the differential equation. It should be given in the form of ``{f(x0): x1, f(x).diff(x).subs(x, x2): x3}`` and so on. For power series solutions, if no initial conditions are specified ``f(0)`` is assumed to be ``C0`` and the power series solution is calculated about 0. ``x0`` is the point about which the power series solution of a differential equation is to be evaluated. ``n`` gives the exponent of the dependent variable up to which the power series solution of a differential equation is to be evaluated. **Hints** Aside from the various solving methods, there are also some meta-hints that you can pass to :py:meth:`~sympy.solvers.ode.dsolve`: ``default``: This uses whatever hint is returned first by :py:meth:`~sympy.solvers.ode.classify_ode`. This is the default argument to :py:meth:`~sympy.solvers.ode.dsolve`. ``all``: To make :py:meth:`~sympy.solvers.ode.dsolve` apply all relevant classification hints, use ``dsolve(ODE, func, hint="all")``. This will return a dictionary of ``hint:solution`` terms. If a hint causes dsolve to raise the ``NotImplementedError``, value of that hint's key will be the exception object raised. The dictionary will also include some special keys: - ``order``: The order of the ODE. See also :py:meth:`~sympy.solvers.deutils.ode_order` in ``deutils.py``. - ``best``: The simplest hint; what would be returned by ``best`` below. - ``best_hint``: The hint that would produce the solution given by ``best``. If more than one hint produces the best solution, the first one in the tuple returned by :py:meth:`~sympy.solvers.ode.classify_ode` is chosen. - ``default``: The solution that would be returned by default. This is the one produced by the hint that appears first in the tuple returned by :py:meth:`~sympy.solvers.ode.classify_ode`. ``all_Integral``: This is the same as ``all``, except if a hint also has a corresponding ``_Integral`` hint, it only returns the ``_Integral`` hint. This is useful if ``all`` causes :py:meth:`~sympy.solvers.ode.dsolve` to hang because of a difficult or impossible integral. This meta-hint will also be much faster than ``all``, because :py:meth:`~sympy.core.expr.Expr.integrate` is an expensive routine. ``best``: To have :py:meth:`~sympy.solvers.ode.dsolve` try all methods and return the simplest one. This takes into account whether the solution is solvable in the function, whether it contains any Integral classes (i.e. unevaluatable integrals), and which one is the shortest in size. See also the :py:meth:`~sympy.solvers.ode.classify_ode` docstring for more info on hints, and the :py:mod:`~sympy.solvers.ode` docstring for a list of all supported hints. **Tips** - You can declare the derivative of an unknown function this way: >>> from sympy import Function, Derivative >>> from sympy.abc import x # x is the independent variable >>> f = Function("f")(x) # f is a function of x >>> # f_ will be the derivative of f with respect to x >>> f_ = Derivative(f, x) - See ``test_ode.py`` for many tests, which serves also as a set of examples for how to use :py:meth:`~sympy.solvers.ode.dsolve`. - :py:meth:`~sympy.solvers.ode.dsolve` always returns an :py:class:`~sympy.core.relational.Equality` class (except for the case when the hint is ``all`` or ``all_Integral``). If possible, it solves the solution explicitly for the function being solved for. Otherwise, it returns an implicit solution. - Arbitrary constants are symbols named ``C1``, ``C2``, and so on. - Because all solutions should be mathematically equivalent, some hints may return the exact same result for an ODE. Often, though, two different hints will return the same solution formatted differently. The two should be equivalent. Also note that sometimes the values of the arbitrary constants in two different solutions may not be the same, because one constant may have "absorbed" other constants into it. - Do ``help(ode.ode_<hintname>)`` to get help more information on a specific hint, where ``<hintname>`` is the name of a hint without ``_Integral``. For system of ordinary differential equations ============================================= **Usage** ``dsolve(eq, func)`` -> Solve a system of ordinary differential equations ``eq`` for ``func`` being list of functions including `x(t)`, `y(t)`, `z(t)` where number of functions in the list depends upon the number of equations provided in ``eq``. **Details** ``eq`` can be any supported system of ordinary differential equations This can either be an :py:class:`~sympy.core.relational.Equality`, or an expression, which is assumed to be equal to ``0``. ``func`` holds ``x(t)`` and ``y(t)`` being functions of one variable which together with some of their derivatives make up the system of ordinary differential equation ``eq``. It is not necessary to provide this; it will be autodetected (and an error raised if it couldn't be detected). **Hints** The hints are formed by parameters returned by classify_sysode, combining them give hints name used later for forming method name. Examples ======== >>> from sympy import Function, dsolve, Eq, Derivative, sin, cos, symbols >>> from sympy.abc import x >>> f = Function('f') >>> dsolve(Derivative(f(x), x, x) + 9*f(x), f(x)) Eq(f(x), C1*sin(3*x) + C2*cos(3*x)) >>> eq = sin(x)*cos(f(x)) + cos(x)*sin(f(x))*f(x).diff(x) >>> dsolve(eq, hint='1st_exact') [Eq(f(x), -acos(C1/cos(x)) + 2*pi), Eq(f(x), acos(C1/cos(x)))] >>> dsolve(eq, hint='almost_linear') [Eq(f(x), -acos(C1/cos(x)) + 2*pi), Eq(f(x), acos(C1/cos(x)))] >>> t = symbols('t') >>> x, y = symbols('x, y', cls=Function) >>> eq = (Eq(Derivative(x(t),t), 12*t*x(t) + 8*y(t)), Eq(Derivative(y(t),t), 21*x(t) + 7*t*y(t))) >>> dsolve(eq) [Eq(x(t), C1*x0(t) + C2*x0(t)*Integral(8*exp(Integral(7*t, t))*exp(Integral(12*t, t))/x0(t)**2, t)), Eq(y(t), C1*y0(t) + C2*(y0(t)*Integral(8*exp(Integral(7*t, t))*exp(Integral(12*t, t))/x0(t)**2, t) + exp(Integral(7*t, t))*exp(Integral(12*t, t))/x0(t)))] >>> eq = (Eq(Derivative(x(t),t),x(t)*y(t)*sin(t)), Eq(Derivative(y(t),t),y(t)**2*sin(t))) >>> dsolve(eq) {Eq(x(t), -exp(C1)/(C2*exp(C1) - cos(t))), Eq(y(t), -1/(C1 - cos(t)))} """ if iterable(eq): from sympy.solvers.ode.systems import dsolve_system # This may have to be changed in future # when we have weakly and strongly # connected components. This have to # changed to show the systems that haven't # been solved. try: sol = dsolve_system(eq, funcs=func, ics=ics, doit=True) return sol[0] if len(sol) == 1 else sol except NotImplementedError: pass match = classify_sysode(eq, func) eq = match['eq'] order = match['order'] func = match['func'] t = list(list(eq[0].atoms(Derivative))[0].atoms(Symbol))[0] # keep highest order term coefficient positive for i in range(len(eq)): for func_ in func: if isinstance(func_, list): pass else: if eq[i].coeff(diff(func[i],t,ode_order(eq[i], func[i]))).is_negative: eq[i] = -eq[i] match['eq'] = eq if len(set(order.values()))!=1: raise ValueError("It solves only those systems of equations whose orders are equal") match['order'] = list(order.values())[0] def recur_len(l): return sum(recur_len(item) if isinstance(item,list) else 1 for item in l) if recur_len(func) != len(eq): raise ValueError("dsolve() and classify_sysode() work with " "number of functions being equal to number of equations") if match['type_of_equation'] is None: raise NotImplementedError else: if match['is_linear'] == True: solvefunc = globals()['sysode_linear_%(no_of_equation)seq_order%(order)s' % match] else: solvefunc = globals()['sysode_nonlinear_%(no_of_equation)seq_order%(order)s' % match] sols = solvefunc(match) if ics: constants = Tuple(*sols).free_symbols - Tuple(*eq).free_symbols solved_constants = solve_ics(sols, func, constants, ics) return [sol.subs(solved_constants) for sol in sols] return sols else: given_hint = hint # hint given by the user # See the docstring of _desolve for more details. hints = _desolve(eq, func=func, hint=hint, simplify=True, xi=xi, eta=eta, type='ode', ics=ics, x0=x0, n=n, **kwargs) eq = hints.pop('eq', eq) all_ = hints.pop('all', False) if all_: retdict = {} failed_hints = {} gethints = classify_ode(eq, dict=True) orderedhints = gethints['ordered_hints'] for hint in hints: try: rv = _helper_simplify(eq, hint, hints[hint], simplify) except NotImplementedError as detail: failed_hints[hint] = detail else: retdict[hint] = rv func = hints[hint]['func'] retdict['best'] = min(list(retdict.values()), key=lambda x: ode_sol_simplicity(x, func, trysolving=not simplify)) if given_hint == 'best': return retdict['best'] for i in orderedhints: if retdict['best'] == retdict.get(i, None): retdict['best_hint'] = i break retdict['default'] = gethints['default'] retdict['order'] = gethints['order'] retdict.update(failed_hints) return retdict else: # The key 'hint' stores the hint needed to be solved for. hint = hints['hint'] return _helper_simplify(eq, hint, hints, simplify, ics=ics) def _helper_simplify(eq, hint, match, simplify=True, ics=None, **kwargs): r""" Helper function of dsolve that calls the respective :py:mod:`~sympy.solvers.ode` functions to solve for the ordinary differential equations. This minimizes the computation in calling :py:meth:`~sympy.solvers.deutils._desolve` multiple times. """ r = match func = r['func'] order = r['order'] match = r[hint] if isinstance(match, SingleODESolver): solvefunc = match elif hint.endswith('_Integral'): solvefunc = globals()['ode_' + hint[:-len('_Integral')]] else: solvefunc = globals()['ode_' + hint] free = eq.free_symbols cons = lambda s: s.free_symbols.difference(free) if simplify: # odesimp() will attempt to integrate, if necessary, apply constantsimp(), # attempt to solve for func, and apply any other hint specific # simplifications if isinstance(solvefunc, SingleODESolver): sols = solvefunc.get_general_solution() else: sols = solvefunc(eq, func, order, match) if iterable(sols): rv = [odesimp(eq, s, func, hint) for s in sols] else: rv = odesimp(eq, sols, func, hint) else: # We still want to integrate (you can disable it separately with the hint) if isinstance(solvefunc, SingleODESolver): exprs = solvefunc.get_general_solution(simplify=False) else: match['simplify'] = False # Some hints can take advantage of this option exprs = solvefunc(eq, func, order, match) if isinstance(exprs, list): rv = [_handle_Integral(expr, func, hint) for expr in exprs] else: rv = _handle_Integral(exprs, func, hint) if isinstance(rv, list): if simplify: rv = _remove_redundant_solutions(eq, rv, order, func.args[0]) if len(rv) == 1: rv = rv[0] if ics and not 'power_series' in hint: if isinstance(rv, (Expr, Eq)): solved_constants = solve_ics([rv], [r['func']], cons(rv), ics) rv = rv.subs(solved_constants) else: rv1 = [] for s in rv: try: solved_constants = solve_ics([s], [r['func']], cons(s), ics) except ValueError: continue rv1.append(s.subs(solved_constants)) if len(rv1) == 1: return rv1[0] rv = rv1 return rv def solve_ics(sols, funcs, constants, ics): """ Solve for the constants given initial conditions ``sols`` is a list of solutions. ``funcs`` is a list of functions. ``constants`` is a list of constants. ``ics`` is the set of initial/boundary conditions for the differential equation. It should be given in the form of ``{f(x0): x1, f(x).diff(x).subs(x, x2): x3}`` and so on. Returns a dictionary mapping constants to values. ``solution.subs(constants)`` will replace the constants in ``solution``. Example ======= >>> # From dsolve(f(x).diff(x) - f(x), f(x)) >>> from sympy import symbols, Eq, exp, Function >>> from sympy.solvers.ode.ode import solve_ics >>> f = Function('f') >>> x, C1 = symbols('x C1') >>> sols = [Eq(f(x), C1*exp(x))] >>> funcs = [f(x)] >>> constants = [C1] >>> ics = {f(0): 2} >>> solved_constants = solve_ics(sols, funcs, constants, ics) >>> solved_constants {C1: 2} >>> sols[0].subs(solved_constants) Eq(f(x), 2*exp(x)) """ # Assume ics are of the form f(x0): value or Subs(diff(f(x), x, n), (x, # x0)): value (currently checked by classify_ode). To solve, replace x # with x0, f(x0) with value, then solve for constants. For f^(n)(x0), # differentiate the solution n times, so that f^(n)(x) appears. x = funcs[0].args[0] diff_sols = [] subs_sols = [] diff_variables = set() for funcarg, value in ics.items(): if isinstance(funcarg, AppliedUndef): x0 = funcarg.args[0] matching_func = [f for f in funcs if f.func == funcarg.func][0] S = sols elif isinstance(funcarg, (Subs, Derivative)): if isinstance(funcarg, Subs): # Make sure it stays a subs. Otherwise subs below will produce # a different looking term. funcarg = funcarg.doit() if isinstance(funcarg, Subs): deriv = funcarg.expr x0 = funcarg.point[0] variables = funcarg.expr.variables matching_func = deriv elif isinstance(funcarg, Derivative): deriv = funcarg x0 = funcarg.variables[0] variables = (x,)*len(funcarg.variables) matching_func = deriv.subs(x0, x) if variables not in diff_variables: for sol in sols: if sol.has(deriv.expr.func): diff_sols.append(Eq(sol.lhs.diff(*variables), sol.rhs.diff(*variables))) diff_variables.add(variables) S = diff_sols else: raise NotImplementedError("Unrecognized initial condition") for sol in S: if sol.has(matching_func): sol2 = sol sol2 = sol2.subs(x, x0) sol2 = sol2.subs(funcarg, value) # This check is necessary because of issue #15724 if not isinstance(sol2, BooleanAtom) or not subs_sols: subs_sols = [s for s in subs_sols if not isinstance(s, BooleanAtom)] subs_sols.append(sol2) # TODO: Use solveset here try: solved_constants = solve(subs_sols, constants, dict=True) except NotImplementedError: solved_constants = [] # XXX: We can't differentiate between the solution not existing because of # invalid initial conditions, and not existing because solve is not smart # enough. If we could use solveset, this might be improvable, but for now, # we use NotImplementedError in this case. if not solved_constants: raise ValueError("Couldn't solve for initial conditions") if solved_constants == True: raise ValueError("Initial conditions did not produce any solutions for constants. Perhaps they are degenerate.") if len(solved_constants) > 1: raise NotImplementedError("Initial conditions produced too many solutions for constants") return solved_constants[0] def classify_ode(eq, func=None, dict=False, ics=None, *, prep=True, xi=None, eta=None, n=None, **kwargs): r""" Returns a tuple of possible :py:meth:`~sympy.solvers.ode.dsolve` classifications for an ODE. The tuple is ordered so that first item is the classification that :py:meth:`~sympy.solvers.ode.dsolve` uses to solve the ODE by default. In general, classifications at the near the beginning of the list will produce better solutions faster than those near the end, thought there are always exceptions. To make :py:meth:`~sympy.solvers.ode.dsolve` use a different classification, use ``dsolve(ODE, func, hint=<classification>)``. See also the :py:meth:`~sympy.solvers.ode.dsolve` docstring for different meta-hints you can use. If ``dict`` is true, :py:meth:`~sympy.solvers.ode.classify_ode` will return a dictionary of ``hint:match`` expression terms. This is intended for internal use by :py:meth:`~sympy.solvers.ode.dsolve`. Note that because dictionaries are ordered arbitrarily, this will most likely not be in the same order as the tuple. You can get help on different hints by executing ``help(ode.ode_hintname)``, where ``hintname`` is the name of the hint without ``_Integral``. See :py:data:`~sympy.solvers.ode.allhints` or the :py:mod:`~sympy.solvers.ode` docstring for a list of all supported hints that can be returned from :py:meth:`~sympy.solvers.ode.classify_ode`. Notes ===== These are remarks on hint names. ``_Integral`` If a classification has ``_Integral`` at the end, it will return the expression with an unevaluated :py:class:`~.Integral` class in it. Note that a hint may do this anyway if :py:meth:`~sympy.core.expr.Expr.integrate` cannot do the integral, though just using an ``_Integral`` will do so much faster. Indeed, an ``_Integral`` hint will always be faster than its corresponding hint without ``_Integral`` because :py:meth:`~sympy.core.expr.Expr.integrate` is an expensive routine. If :py:meth:`~sympy.solvers.ode.dsolve` hangs, it is probably because :py:meth:`~sympy.core.expr.Expr.integrate` is hanging on a tough or impossible integral. Try using an ``_Integral`` hint or ``all_Integral`` to get it return something. Note that some hints do not have ``_Integral`` counterparts. This is because :py:func:`~sympy.integrals.integrals.integrate` is not used in solving the ODE for those method. For example, `n`\th order linear homogeneous ODEs with constant coefficients do not require integration to solve, so there is no ``nth_linear_homogeneous_constant_coeff_Integrate`` hint. You can easily evaluate any unevaluated :py:class:`~sympy.integrals.integrals.Integral`\s in an expression by doing ``expr.doit()``. Ordinals Some hints contain an ordinal such as ``1st_linear``. This is to help differentiate them from other hints, as well as from other methods that may not be implemented yet. If a hint has ``nth`` in it, such as the ``nth_linear`` hints, this means that the method used to applies to ODEs of any order. ``indep`` and ``dep`` Some hints contain the words ``indep`` or ``dep``. These reference the independent variable and the dependent function, respectively. For example, if an ODE is in terms of `f(x)`, then ``indep`` will refer to `x` and ``dep`` will refer to `f`. ``subs`` If a hints has the word ``subs`` in it, it means the the ODE is solved by substituting the expression given after the word ``subs`` for a single dummy variable. This is usually in terms of ``indep`` and ``dep`` as above. The substituted expression will be written only in characters allowed for names of Python objects, meaning operators will be spelled out. For example, ``indep``/``dep`` will be written as ``indep_div_dep``. ``coeff`` The word ``coeff`` in a hint refers to the coefficients of something in the ODE, usually of the derivative terms. See the docstring for the individual methods for more info (``help(ode)``). This is contrast to ``coefficients``, as in ``undetermined_coefficients``, which refers to the common name of a method. ``_best`` Methods that have more than one fundamental way to solve will have a hint for each sub-method and a ``_best`` meta-classification. This will evaluate all hints and return the best, using the same considerations as the normal ``best`` meta-hint. Examples ======== >>> from sympy import Function, classify_ode, Eq >>> from sympy.abc import x >>> f = Function('f') >>> classify_ode(Eq(f(x).diff(x), 0), f(x)) ('nth_algebraic', 'separable', '1st_exact', '1st_linear', 'Bernoulli', '1st_homogeneous_coeff_best', '1st_homogeneous_coeff_subs_indep_div_dep', '1st_homogeneous_coeff_subs_dep_div_indep', '1st_power_series', 'lie_group', 'nth_linear_constant_coeff_homogeneous', 'nth_linear_euler_eq_homogeneous', 'nth_algebraic_Integral', 'separable_Integral', '1st_exact_Integral', '1st_linear_Integral', 'Bernoulli_Integral', '1st_homogeneous_coeff_subs_indep_div_dep_Integral', '1st_homogeneous_coeff_subs_dep_div_indep_Integral') >>> classify_ode(f(x).diff(x, 2) + 3*f(x).diff(x) + 2*f(x) - 4) ('nth_linear_constant_coeff_undetermined_coefficients', 'nth_linear_constant_coeff_variation_of_parameters', 'nth_linear_constant_coeff_variation_of_parameters_Integral') """ ics = sympify(ics) if func and len(func.args) != 1: raise ValueError("dsolve() and classify_ode() only " "work with functions of one variable, not %s" % func) if isinstance(eq, Equality): eq = eq.lhs - eq.rhs # Some methods want the unprocessed equation eq_orig = eq if prep or func is None: eq, func_ = _preprocess(eq, func) if func is None: func = func_ x = func.args[0] f = func.func y = Dummy('y') terms = n order = ode_order(eq, f(x)) # hint:matchdict or hint:(tuple of matchdicts) # Also will contain "default":<default hint> and "order":order items. matching_hints = {"order": order} df = f(x).diff(x) a = Wild('a', exclude=[f(x)]) d = Wild('d', exclude=[df, f(x).diff(x, 2)]) e = Wild('e', exclude=[df]) n = Wild('n', exclude=[x, f(x), df]) c1 = Wild('c1', exclude=[x]) a3 = Wild('a3', exclude=[f(x), df, f(x).diff(x, 2)]) b3 = Wild('b3', exclude=[f(x), df, f(x).diff(x, 2)]) c3 = Wild('c3', exclude=[f(x), df, f(x).diff(x, 2)]) r3 = {'xi': xi, 'eta': eta} # Used for the lie_group hint boundary = {} # Used to extract initial conditions C1 = Symbol("C1") # Preprocessing to get the initial conditions out if ics is not None: for funcarg in ics: # Separating derivatives if isinstance(funcarg, (Subs, Derivative)): # f(x).diff(x).subs(x, 0) is a Subs, but f(x).diff(x).subs(x, # y) is a Derivative if isinstance(funcarg, Subs): deriv = funcarg.expr old = funcarg.variables[0] new = funcarg.point[0] elif isinstance(funcarg, Derivative): deriv = funcarg # No information on this. Just assume it was x old = x new = funcarg.variables[0] if (isinstance(deriv, Derivative) and isinstance(deriv.args[0], AppliedUndef) and deriv.args[0].func == f and len(deriv.args[0].args) == 1 and old == x and not new.has(x) and all(i == deriv.variables[0] for i in deriv.variables) and not ics[funcarg].has(f)): dorder = ode_order(deriv, x) temp = 'f' + str(dorder) boundary.update({temp: new, temp + 'val': ics[funcarg]}) else: raise ValueError("Enter valid boundary conditions for Derivatives") # Separating functions elif isinstance(funcarg, AppliedUndef): if (funcarg.func == f and len(funcarg.args) == 1 and not funcarg.args[0].has(x) and not ics[funcarg].has(f)): boundary.update({'f0': funcarg.args[0], 'f0val': ics[funcarg]}) else: raise ValueError("Enter valid boundary conditions for Function") else: raise ValueError("Enter boundary conditions of the form ics={f(point): value, f(x).diff(x, order).subs(x, point): value}") # Any ODE that can be solved with a combination of algebra and # integrals e.g.: # d^3/dx^3(x y) = F(x) ode = SingleODEProblem(eq_orig, func, x, prep=prep) solvers = { NthAlgebraic: ('nth_algebraic',), FirstExact:('1st_exact',), FirstLinear: ('1st_linear',), AlmostLinear: ('almost_linear',), Bernoulli: ('Bernoulli',), Factorable: ('factorable',), RiccatiSpecial: ('Riccati_special_minus2',), SecondNonlinearAutonomousConserved: ('2nd_nonlinear_autonomous_conserved',), Liouville: ('Liouville',), Separable: ('separable',), SeparableReduced: ('separable_reduced',), HomogeneousCoeffSubsDepDivIndep: ('1st_homogeneous_coeff_subs_dep_div_indep',), HomogeneousCoeffSubsIndepDivDep: ('1st_homogeneous_coeff_subs_indep_div_dep',), HomogeneousCoeffBest: ('1st_homogeneous_coeff_best',), LinearCoefficients: ('linear_coefficients',), } for solvercls in solvers: solver = solvercls(ode) if solver.matches(): for hints in solvers[solvercls]: matching_hints[hints] = solver if solvercls.has_integral: matching_hints[hints + "_Integral"] = solver eq = expand(eq) # Precondition to try remove f(x) from highest order derivative reduced_eq = None if eq.is_Add: deriv_coef = eq.coeff(f(x).diff(x, order)) if deriv_coef not in (1, 0): r = deriv_coef.match(a*f(x)**c1) if r and r[c1]: den = f(x)**r[c1] reduced_eq = Add(*[arg/den for arg in eq.args]) if not reduced_eq: reduced_eq = eq if order == 1: # NON-REDUCED FORM OF EQUATION matches r = collect(eq, df, exact=True).match(d + e * df) if r: r['d'] = d r['e'] = e r['y'] = y r[d] = r[d].subs(f(x), y) r[e] = r[e].subs(f(x), y) # FIRST ORDER POWER SERIES WHICH NEEDS INITIAL CONDITIONS # TODO: Hint first order series should match only if d/e is analytic. # For now, only d/e and (d/e).diff(arg) is checked for existence at # at a given point. # This is currently done internally in ode_1st_power_series. point = boundary.get('f0', 0) value = boundary.get('f0val', C1) check = cancel(r[d]/r[e]) check1 = check.subs({x: point, y: value}) if not check1.has(oo) and not check1.has(zoo) and \ not check1.has(NaN) and not check1.has(-oo): check2 = (check1.diff(x)).subs({x: point, y: value}) if not check2.has(oo) and not check2.has(zoo) and \ not check2.has(NaN) and not check2.has(-oo): rseries = r.copy() rseries.update({'terms': terms, 'f0': point, 'f0val': value}) matching_hints["1st_power_series"] = rseries r3.update(r) # Any first order ODE can be ideally solved by the Lie Group # method matching_hints["lie_group"] = r3 elif order == 2: # Homogeneous second order differential equation of the form # a3*f(x).diff(x, 2) + b3*f(x).diff(x) + c3 # It has a definite power series solution at point x0 if, b3/a3 and c3/a3 # are analytic at x0. deq = a3*(f(x).diff(x, 2)) + b3*df + c3*f(x) r = collect(reduced_eq, [f(x).diff(x, 2), f(x).diff(x), f(x)]).match(deq) ordinary = False if r: if not all([r[key].is_polynomial() for key in r]): n, d = reduced_eq.as_numer_denom() reduced_eq = expand(n) r = collect(reduced_eq, [f(x).diff(x, 2), f(x).diff(x), f(x)]).match(deq) if r and r[a3] != 0: p = cancel(r[b3]/r[a3]) # Used below q = cancel(r[c3]/r[a3]) # Used below point = kwargs.get('x0', 0) check = p.subs(x, point) if not check.has(oo, NaN, zoo, -oo): check = q.subs(x, point) if not check.has(oo, NaN, zoo, -oo): ordinary = True r.update({'a3': a3, 'b3': b3, 'c3': c3, 'x0': point, 'terms': terms}) matching_hints["2nd_power_series_ordinary"] = r # Checking if the differential equation has a regular singular point # at x0. It has a regular singular point at x0, if (b3/a3)*(x - x0) # and (c3/a3)*((x - x0)**2) are analytic at x0. if not ordinary: p = cancel((x - point)*p) check = p.subs(x, point) if not check.has(oo, NaN, zoo, -oo): q = cancel(((x - point)**2)*q) check = q.subs(x, point) if not check.has(oo, NaN, zoo, -oo): coeff_dict = {'p': p, 'q': q, 'x0': point, 'terms': terms} matching_hints["2nd_power_series_regular"] = coeff_dict # For Hypergeometric solutions. _r = {} _r.update(r) rn = match_2nd_hypergeometric(_r, func) if rn: matching_hints["2nd_hypergeometric"] = rn matching_hints["2nd_hypergeometric_Integral"] = rn # If the ODE has regular singular point at x0 and is of the form # Eq((x)**2*Derivative(y(x), x, x) + x*Derivative(y(x), x) + # (a4**2*x**(2*p)-n**2)*y(x) thus Bessel's equation rn = match_2nd_linear_bessel(r, f(x)) if rn: matching_hints["2nd_linear_bessel"] = rn # If the ODE is ordinary and is of the form of Airy's Equation # Eq(x**2*Derivative(y(x),x,x)-(ax+b)*y(x)) if p.is_zero: a4 = Wild('a4', exclude=[x,f(x),df]) b4 = Wild('b4', exclude=[x,f(x),df]) rn = q.match(a4+b4*x) if rn and rn[b4] != 0: rn = {'b':rn[a4],'m':rn[b4]} matching_hints["2nd_linear_airy"] = rn if order > 0: # Any ODE that can be solved with a substitution and # repeated integration e.g.: # `d^2/dx^2(y) + x*d/dx(y) = constant #f'(x) must be finite for this to work r = _nth_order_reducible_match(reduced_eq, func) if r: matching_hints['nth_order_reducible'] = r # nth order linear ODE # a_n(x)y^(n) + ... + a_1(x)y' + a_0(x)y = F(x) = b r = _nth_linear_match(reduced_eq, func, order) # Constant coefficient case (a_i is constant for all i) if r and not any(r[i].has(x) for i in r if i >= 0): # Inhomogeneous case: F(x) is not identically 0 if r[-1]: eq_homogeneous = Add(eq,-r[-1]) undetcoeff = _undetermined_coefficients_match(r[-1], x, func, eq_homogeneous) s = "nth_linear_constant_coeff_variation_of_parameters" matching_hints[s] = r matching_hints[s + "_Integral"] = r if undetcoeff['test']: r['trialset'] = undetcoeff['trialset'] matching_hints[ "nth_linear_constant_coeff_undetermined_coefficients" ] = r # Homogeneous case: F(x) is identically 0 else: matching_hints["nth_linear_constant_coeff_homogeneous"] = r # nth order Euler equation a_n*x**n*y^(n) + ... + a_1*x*y' + a_0*y = F(x) #In case of Homogeneous euler equation F(x) = 0 def _test_term(coeff, order): r""" Linear Euler ODEs have the form K*x**order*diff(y(x),x,order) = F(x), where K is independent of x and y(x), order>= 0. So we need to check that for each term, coeff == K*x**order from some K. We have a few cases, since coeff may have several different types. """ if order < 0: raise ValueError("order should be greater than 0") if coeff == 0: return True if order == 0: if x in coeff.free_symbols: return False return True if coeff.is_Mul: if coeff.has(f(x)): return False return x**order in coeff.args elif coeff.is_Pow: return coeff.as_base_exp() == (x, order) elif order == 1: return x == coeff return False # Find coefficient for highest derivative, multiply coefficients to # bring the equation into Euler form if possible r_rescaled = None if r is not None: coeff = r[order] factor = x**order / coeff r_rescaled = {i: factor*r[i] for i in r if i != 'trialset'} # XXX: Mixing up the trialset with the coefficients is error-prone. # These should be separated as something like r['coeffs'] and # r['trialset'] if r_rescaled and not any(not _test_term(r_rescaled[i], i) for i in r_rescaled if i != 'trialset' and i >= 0): if not r_rescaled[-1]: matching_hints["nth_linear_euler_eq_homogeneous"] = r_rescaled else: matching_hints["nth_linear_euler_eq_nonhomogeneous_variation_of_parameters"] = r_rescaled matching_hints["nth_linear_euler_eq_nonhomogeneous_variation_of_parameters_Integral"] = r_rescaled e, re = posify(r_rescaled[-1].subs(x, exp(x))) undetcoeff = _undetermined_coefficients_match(e.subs(re), x) if undetcoeff['test']: r_rescaled['trialset'] = undetcoeff['trialset'] matching_hints["nth_linear_euler_eq_nonhomogeneous_undetermined_coefficients"] = r_rescaled # Order keys based on allhints. retlist = [i for i in allhints if i in matching_hints] if dict: # Dictionaries are ordered arbitrarily, so make note of which # hint would come first for dsolve(). Use an ordered dict in Py 3. matching_hints["default"] = retlist[0] if retlist else None matching_hints["ordered_hints"] = tuple(retlist) return matching_hints else: return tuple(retlist) def equivalence(max_num_pow, dem_pow): # this function is made for checking the equivalence with 2F1 type of equation. # max_num_pow is the value of maximum power of x in numerator # and dem_pow is list of powers of different factor of form (a*x b). # reference from table 1 in paper - "Non-Liouvillian solutions for second order # linear ODEs" by L. Chan, E.S. Cheb-Terrab. # We can extend it for 1F1 and 0F1 type also. if max_num_pow == 2: if dem_pow in [[2, 2], [2, 2, 2]]: return "2F1" elif max_num_pow == 1: if dem_pow in [[1, 2, 2], [2, 2, 2], [1, 2], [2, 2]]: return "2F1" elif max_num_pow == 0: if dem_pow in [[1, 1, 2], [2, 2], [1 ,2, 2], [1, 1], [2], [1, 2], [2, 2]]: return "2F1" return None def equivalence_hypergeometric(A, B, func): from sympy import factor # This method for finding the equivalence is only for 2F1 type. # We can extend it for 1F1 and 0F1 type also. x = func.args[0] # making given equation in normal form I1 = factor(cancel(A.diff(x)/2 + A**2/4 - B)) # computing shifted invariant(J1) of the equation J1 = factor(cancel(x**2*I1 + S(1)/4)) num, dem = J1.as_numer_denom() num = powdenest(expand(num)) dem = powdenest(expand(dem)) pow_num = set() pow_dem = set() # this function will compute the different powers of variable(x) in J1. # then it will help in finding value of k. k is power of x such that we can express # J1 = x**k * J0(x**k) then all the powers in J0 become integers. def _power_counting(num): _pow = {0} for val in num: if val.has(x): if isinstance(val, Pow) and val.as_base_exp()[0] == x: _pow.add(val.as_base_exp()[1]) elif val == x: _pow.add(val.as_base_exp()[1]) else: _pow.update(_power_counting(val.args)) return _pow pow_num = _power_counting((num, )) pow_dem = _power_counting((dem, )) pow_dem.update(pow_num) _pow = pow_dem k = gcd(_pow) # computing I0 of the given equation I0 = powdenest(simplify(factor(((J1/k**2) - S(1)/4)/((x**k)**2))), force=True) I0 = factor(cancel(powdenest(I0.subs(x, x**(S(1)/k)), force=True))) num, dem = I0.as_numer_denom() max_num_pow = max(_power_counting((num, ))) dem_args = dem.args sing_point = [] dem_pow = [] # calculating singular point of I0. for arg in dem_args: if arg.has(x): if isinstance(arg, Pow): # (x-a)**n dem_pow.append(arg.as_base_exp()[1]) sing_point.append(list(roots(arg.as_base_exp()[0], x).keys())[0]) else: # (x-a) type dem_pow.append(arg.as_base_exp()[1]) sing_point.append(list(roots(arg, x).keys())[0]) dem_pow.sort() # checking if equivalence is exists or not. if equivalence(max_num_pow, dem_pow) == "2F1": return {'I0':I0, 'k':k, 'sing_point':sing_point, 'type':"2F1"} else: return None def ode_2nd_hypergeometric(eq, func, order, match): from sympy.simplify.hyperexpand import hyperexpand from sympy import factor x = func.args[0] C0, C1 = get_numbered_constants(eq, num=2) a = match['a'] b = match['b'] c = match['c'] A = match['A'] # B = match['B'] sol = None if match['type'] == "2F1": if c.is_integer == False: sol = C0*hyper([a, b], [c], x) + C1*hyper([a-c+1, b-c+1], [2-c], x)*x**(1-c) elif c == 1: y2 = Integral(exp(Integral((-(a+b+1)*x + c)/(x**2-x), x))/(hyperexpand(hyper([a, b], [c], x))**2), x)*hyper([a, b], [c], x) sol = C0*hyper([a, b], [c], x) + C1*y2 elif (c-a-b).is_integer == False: sol = C0*hyper([a, b], [1+a+b-c], 1-x) + C1*hyper([c-a, c-b], [1+c-a-b], 1-x)*(1-x)**(c-a-b) if sol is None: raise NotImplementedError("The given ODE " + str(eq) + " cannot be solved by" + " the hypergeometric method") # applying transformation in the solution subs = match['mobius'] dtdx = simplify(1/(subs.diff(x))) _B = ((a + b + 1)*x - c).subs(x, subs)*dtdx _B = factor(_B + ((x**2 -x).subs(x, subs))*(dtdx.diff(x)*dtdx)) _A = factor((x**2 - x).subs(x, subs)*(dtdx**2)) e = exp(logcombine(Integral(cancel(_B/(2*_A)), x), force=True)) sol = sol.subs(x, match['mobius']) sol = sol.subs(x, x**match['k']) e = e.subs(x, x**match['k']) if not A.is_zero: e1 = Integral(A/2, x) e1 = exp(logcombine(e1, force=True)) sol = cancel((e/e1)*x**((-match['k']+1)/2))*sol sol = Eq(func, sol) return sol sol = cancel((e)*x**((-match['k']+1)/2))*sol sol = Eq(func, sol) return sol def match_2nd_2F1_hypergeometric(I, k, sing_point, func): from sympy import factor x = func.args[0] a = Wild("a") b = Wild("b") c = Wild("c") t = Wild("t") s = Wild("s") r = Wild("r") alpha = Wild("alpha") beta = Wild("beta") gamma = Wild("gamma") delta = Wild("delta") rn = {'type':None} # I0 of the standerd 2F1 equation. I0 = ((a-b+1)*(a-b-1)*x**2 + 2*((1-a-b)*c + 2*a*b)*x + c*(c-2))/(4*x**2*(x-1)**2) if sing_point != [0, 1]: # If singular point is [0, 1] then we have standerd equation. eqs = [] sing_eqs = [-beta/alpha, -delta/gamma, (delta-beta)/(alpha-gamma)] # making equations for the finding the mobius transformation for i in range(3): if i<len(sing_point): eqs.append(Eq(sing_eqs[i], sing_point[i])) else: eqs.append(Eq(1/sing_eqs[i], 0)) # solving above equations for the mobius transformation _beta = -alpha*sing_point[0] _delta = -gamma*sing_point[1] _gamma = alpha if len(sing_point) == 3: _gamma = (_beta + sing_point[2]*alpha)/(sing_point[2] - sing_point[1]) mob = (alpha*x + beta)/(gamma*x + delta) mob = mob.subs(beta, _beta) mob = mob.subs(delta, _delta) mob = mob.subs(gamma, _gamma) mob = cancel(mob) t = (beta - delta*x)/(gamma*x - alpha) t = cancel(((t.subs(beta, _beta)).subs(delta, _delta)).subs(gamma, _gamma)) else: mob = x t = x # applying mobius transformation in I to make it into I0. I = I.subs(x, t) I = I*(t.diff(x))**2 I = factor(I) dict_I = {x**2:0, x:0, 1:0} I0_num, I0_dem = I0.as_numer_denom() # collecting coeff of (x**2, x), of the standerd equation. # substituting (a-b) = s, (a+b) = r dict_I0 = {x**2:s**2 - 1, x:(2*(1-r)*c + (r+s)*(r-s)), 1:c*(c-2)} # collecting coeff of (x**2, x) from I0 of the given equation. dict_I.update(collect(expand(cancel(I*I0_dem)), [x**2, x], evaluate=False)) eqs = [] # We are comparing the coeff of powers of different x, for finding the values of # parameters of standerd equation. for key in [x**2, x, 1]: eqs.append(Eq(dict_I[key], dict_I0[key])) # We can have many possible roots for the equation. # I am selecting the root on the basis that when we have # standard equation eq = x*(x-1)*f(x).diff(x, 2) + ((a+b+1)*x-c)*f(x).diff(x) + a*b*f(x) # then root should be a, b, c. _c = 1 - factor(sqrt(1+eqs[2].lhs)) if not _c.has(Symbol): _c = min(list(roots(eqs[2], c))) _s = factor(sqrt(eqs[0].lhs + 1)) _r = _c - factor(sqrt(_c**2 + _s**2 + eqs[1].lhs - 2*_c)) _a = (_r + _s)/2 _b = (_r - _s)/2 rn = {'a':simplify(_a), 'b':simplify(_b), 'c':simplify(_c), 'k':k, 'mobius':mob, 'type':"2F1"} return rn def match_2nd_hypergeometric(r, func): x = func.args[0] a3 = Wild('a3', exclude=[func, func.diff(x), func.diff(x, 2)]) b3 = Wild('b3', exclude=[func, func.diff(x), func.diff(x, 2)]) c3 = Wild('c3', exclude=[func, func.diff(x), func.diff(x, 2)]) A = cancel(r[b3]/r[a3]) B = cancel(r[c3]/r[a3]) d = equivalence_hypergeometric(A, B, func) rn = None if d: if d['type'] == "2F1": rn = match_2nd_2F1_hypergeometric(d['I0'], d['k'], d['sing_point'], func) if rn is not None: rn.update({'A':A, 'B':B}) # We can extend it for 1F1 and 0F1 type also. return rn def match_2nd_linear_bessel(r, func): from sympy.polys.polytools import factor # eq = a3*f(x).diff(x, 2) + b3*f(x).diff(x) + c3*f(x) f = func x = func.args[0] df = f.diff(x) a = Wild('a', exclude=[f,df]) b = Wild('b', exclude=[x, f,df]) a4 = Wild('a4', exclude=[x,f,df]) b4 = Wild('b4', exclude=[x,f,df]) c4 = Wild('c4', exclude=[x,f,df]) d4 = Wild('d4', exclude=[x,f,df]) a3 = Wild('a3', exclude=[f, df, f.diff(x, 2)]) b3 = Wild('b3', exclude=[f, df, f.diff(x, 2)]) c3 = Wild('c3', exclude=[f, df, f.diff(x, 2)]) # leading coeff of f(x).diff(x, 2) coeff = factor(r[a3]).match(a4*(x-b)**b4) if coeff: # if coeff[b4] = 0 means constant coefficient if coeff[b4] == 0: return None point = coeff[b] else: return None if point: r[a3] = simplify(r[a3].subs(x, x+point)) r[b3] = simplify(r[b3].subs(x, x+point)) r[c3] = simplify(r[c3].subs(x, x+point)) # making a3 in the form of x**2 r[a3] = cancel(r[a3]/(coeff[a4]*(x)**(-2+coeff[b4]))) r[b3] = cancel(r[b3]/(coeff[a4]*(x)**(-2+coeff[b4]))) r[c3] = cancel(r[c3]/(coeff[a4]*(x)**(-2+coeff[b4]))) # checking if b3 is of form c*(x-b) coeff1 = factor(r[b3]).match(a4*(x)) if coeff1 is None: return None # c3 maybe of very complex form so I am simply checking (a - b) form # if yes later I will match with the standerd form of bessel in a and b # a, b are wild variable defined above. _coeff2 = r[c3].match(a - b) if _coeff2 is None: return None # matching with standerd form for c3 coeff2 = factor(_coeff2[a]).match(c4**2*(x)**(2*a4)) if coeff2 is None: return None if _coeff2[b] == 0: coeff2[d4] = 0 else: coeff2[d4] = factor(_coeff2[b]).match(d4**2)[d4] rn = {'n':coeff2[d4], 'a4':coeff2[c4], 'd4':coeff2[a4]} rn['c4'] = coeff1[a4] rn['b4'] = point return rn def classify_sysode(eq, funcs=None, **kwargs): r""" Returns a dictionary of parameter names and values that define the system of ordinary differential equations in ``eq``. The parameters are further used in :py:meth:`~sympy.solvers.ode.dsolve` for solving that system. Some parameter names and values are: 'is_linear' (boolean), which tells whether the given system is linear. Note that "linear" here refers to the operator: terms such as ``x*diff(x,t)`` are nonlinear, whereas terms like ``sin(t)*diff(x,t)`` are still linear operators. 'func' (list) contains the :py:class:`~sympy.core.function.Function`s that appear with a derivative in the ODE, i.e. those that we are trying to solve the ODE for. 'order' (dict) with the maximum derivative for each element of the 'func' parameter. 'func_coeff' (dict or Matrix) with the coefficient for each triple ``(equation number, function, order)```. The coefficients are those subexpressions that do not appear in 'func', and hence can be considered constant for purposes of ODE solving. The value of this parameter can also be a Matrix if the system of ODEs are linear first order of the form X' = AX where X is the vector of dependent variables. Here, this function returns the coefficient matrix A. 'eq' (list) with the equations from ``eq``, sympified and transformed into expressions (we are solving for these expressions to be zero). 'no_of_equations' (int) is the number of equations (same as ``len(eq)``). 'type_of_equation' (string) is an internal classification of the type of ODE. 'is_constant' (boolean), which tells if the system of ODEs is constant coefficient or not. This key is temporary addition for now and is in the match dict only when the system of ODEs is linear first order constant coefficient homogeneous. So, this key's value is True for now if it is available else it doesn't exist. 'is_homogeneous' (boolean), which tells if the system of ODEs is homogeneous. Like the key 'is_constant', this key is a temporary addition and it is True since this key value is available only when the system is linear first order constant coefficient homogeneous. References ========== -http://eqworld.ipmnet.ru/en/solutions/sysode/sode-toc1.htm -A. D. Polyanin and A. V. Manzhirov, Handbook of Mathematics for Engineers and Scientists Examples ======== >>> from sympy import Function, Eq, symbols, diff >>> from sympy.solvers.ode.ode import classify_sysode >>> from sympy.abc import t >>> f, x, y = symbols('f, x, y', cls=Function) >>> k, l, m, n = symbols('k, l, m, n', Integer=True) >>> x1 = diff(x(t), t) ; y1 = diff(y(t), t) >>> x2 = diff(x(t), t, t) ; y2 = diff(y(t), t, t) >>> eq = (Eq(x1, 12*x(t) - 6*y(t)), Eq(y1, 11*x(t) + 3*y(t))) >>> classify_sysode(eq) {'eq': [-12*x(t) + 6*y(t) + Derivative(x(t), t), -11*x(t) - 3*y(t) + Derivative(y(t), t)], 'func': [x(t), y(t)], 'func_coeff': {(0, x(t), 0): -12, (0, x(t), 1): 1, (0, y(t), 0): 6, (0, y(t), 1): 0, (1, x(t), 0): -11, (1, x(t), 1): 0, (1, y(t), 0): -3, (1, y(t), 1): 1}, 'is_linear': True, 'no_of_equation': 2, 'order': {x(t): 1, y(t): 1}, 'type_of_equation': None} >>> eq = (Eq(diff(x(t),t), 5*t*x(t) + t**2*y(t) + 2), Eq(diff(y(t),t), -t**2*x(t) + 5*t*y(t))) >>> classify_sysode(eq) {'eq': [-t**2*y(t) - 5*t*x(t) + Derivative(x(t), t) - 2, t**2*x(t) - 5*t*y(t) + Derivative(y(t), t)], 'func': [x(t), y(t)], 'func_coeff': {(0, x(t), 0): -5*t, (0, x(t), 1): 1, (0, y(t), 0): -t**2, (0, y(t), 1): 0, (1, x(t), 0): t**2, (1, x(t), 1): 0, (1, y(t), 0): -5*t, (1, y(t), 1): 1}, 'is_linear': True, 'no_of_equation': 2, 'order': {x(t): 1, y(t): 1}, 'type_of_equation': None} """ # Sympify equations and convert iterables of equations into # a list of equations def _sympify(eq): return list(map(sympify, eq if iterable(eq) else [eq])) eq, funcs = (_sympify(w) for w in [eq, funcs]) for i, fi in enumerate(eq): if isinstance(fi, Equality): eq[i] = fi.lhs - fi.rhs t = list(list(eq[0].atoms(Derivative))[0].atoms(Symbol))[0] matching_hints = {"no_of_equation":i+1} matching_hints['eq'] = eq if i==0: raise ValueError("classify_sysode() works for systems of ODEs. " "For scalar ODEs, classify_ode should be used") # find all the functions if not given order = dict() if funcs==[None]: funcs = _extract_funcs(eq) funcs = list(set(funcs)) if len(funcs) != len(eq): raise ValueError("Number of functions given is not equal to the number of equations %s" % funcs) # This logic of list of lists in funcs to # be replaced later. func_dict = dict() for func in funcs: if not order.get(func, False): max_order = 0 for i, eqs_ in enumerate(eq): order_ = ode_order(eqs_,func) if max_order < order_: max_order = order_ eq_no = i if eq_no in func_dict: func_dict[eq_no] = [func_dict[eq_no], func] else: func_dict[eq_no] = func order[func] = max_order funcs = [func_dict[i] for i in range(len(func_dict))] matching_hints['func'] = funcs for func in funcs: if isinstance(func, list): for func_elem in func: if len(func_elem.args) != 1: raise ValueError("dsolve() and classify_sysode() work with " "functions of one variable only, not %s" % func) else: if func and len(func.args) != 1: raise ValueError("dsolve() and classify_sysode() work with " "functions of one variable only, not %s" % func) # find the order of all equation in system of odes matching_hints["order"] = order # find coefficients of terms f(t), diff(f(t),t) and higher derivatives # and similarly for other functions g(t), diff(g(t),t) in all equations. # Here j denotes the equation number, funcs[l] denotes the function about # which we are talking about and k denotes the order of function funcs[l] # whose coefficient we are calculating. def linearity_check(eqs, j, func, is_linear_): for k in range(order[func] + 1): func_coef[j, func, k] = collect(eqs.expand(), [diff(func, t, k)]).coeff(diff(func, t, k)) if is_linear_ == True: if func_coef[j, func, k] == 0: if k == 0: coef = eqs.as_independent(func, as_Add=True)[1] for xr in range(1, ode_order(eqs,func) + 1): coef -= eqs.as_independent(diff(func, t, xr), as_Add=True)[1] if coef != 0: is_linear_ = False else: if eqs.as_independent(diff(func, t, k), as_Add=True)[1]: is_linear_ = False else: for func_ in funcs: if isinstance(func_, list): for elem_func_ in func_: dep = func_coef[j, func, k].as_independent(elem_func_, as_Add=True)[1] if dep != 0: is_linear_ = False else: dep = func_coef[j, func, k].as_independent(func_, as_Add=True)[1] if dep != 0: is_linear_ = False return is_linear_ func_coef = {} is_linear = True for j, eqs in enumerate(eq): for func in funcs: if isinstance(func, list): for func_elem in func: is_linear = linearity_check(eqs, j, func_elem, is_linear) else: is_linear = linearity_check(eqs, j, func, is_linear) matching_hints['func_coeff'] = func_coef matching_hints['is_linear'] = is_linear if len(set(order.values())) == 1: order_eq = list(matching_hints['order'].values())[0] if matching_hints['is_linear'] == True: if matching_hints['no_of_equation'] == 2: if order_eq == 1: type_of_equation = check_linear_2eq_order1(eq, funcs, func_coef) else: type_of_equation = None # If the equation doesn't match up with any of the # general case solvers in systems.py and the number # of equations is greater than 2, then NotImplementedError # should be raised. else: type_of_equation = None else: if matching_hints['no_of_equation'] == 2: if order_eq == 1: type_of_equation = check_nonlinear_2eq_order1(eq, funcs, func_coef) else: type_of_equation = None elif matching_hints['no_of_equation'] == 3: if order_eq == 1: type_of_equation = check_nonlinear_3eq_order1(eq, funcs, func_coef) else: type_of_equation = None else: type_of_equation = None else: type_of_equation = None matching_hints['type_of_equation'] = type_of_equation return matching_hints def check_linear_2eq_order1(eq, func, func_coef): x = func[0].func y = func[1].func fc = func_coef t = list(list(eq[0].atoms(Derivative))[0].atoms(Symbol))[0] r = dict() # for equations Eq(a1*diff(x(t),t), b1*x(t) + c1*y(t) + d1) # and Eq(a2*diff(y(t),t), b2*x(t) + c2*y(t) + d2) r['a1'] = fc[0,x(t),1] ; r['a2'] = fc[1,y(t),1] r['b1'] = -fc[0,x(t),0]/fc[0,x(t),1] ; r['b2'] = -fc[1,x(t),0]/fc[1,y(t),1] r['c1'] = -fc[0,y(t),0]/fc[0,x(t),1] ; r['c2'] = -fc[1,y(t),0]/fc[1,y(t),1] forcing = [S.Zero,S.Zero] for i in range(2): for j in Add.make_args(eq[i]): if not j.has(x(t), y(t)): forcing[i] += j if not (forcing[0].has(t) or forcing[1].has(t)): # We can handle homogeneous case and simple constant forcings r['d1'] = forcing[0] r['d2'] = forcing[1] else: # Issue #9244: nonhomogeneous linear systems are not supported return None # Conditions to check for type 6 whose equations are Eq(diff(x(t),t), f(t)*x(t) + g(t)*y(t)) and # Eq(diff(y(t),t), a*[f(t) + a*h(t)]x(t) + a*[g(t) - h(t)]*y(t)) p = 0 q = 0 p1 = cancel(r['b2']/(cancel(r['b2']/r['c2']).as_numer_denom()[0])) p2 = cancel(r['b1']/(cancel(r['b1']/r['c1']).as_numer_denom()[0])) for n, i in enumerate([p1, p2]): for j in Mul.make_args(collect_const(i)): if not j.has(t): q = j if q and n==0: if ((r['b2']/j - r['b1'])/(r['c1'] - r['c2']/j)) == j: p = 1 elif q and n==1: if ((r['b1']/j - r['b2'])/(r['c2'] - r['c1']/j)) == j: p = 2 # End of condition for type 6 if r['d1']!=0 or r['d2']!=0: return None else: if all(not r[k].has(t) for k in 'a1 a2 b1 b2 c1 c2'.split()): return None else: r['b1'] = r['b1']/r['a1'] ; r['b2'] = r['b2']/r['a2'] r['c1'] = r['c1']/r['a1'] ; r['c2'] = r['c2']/r['a2'] if p: return "type6" else: # Equations for type 7 are Eq(diff(x(t),t), f(t)*x(t) + g(t)*y(t)) and Eq(diff(y(t),t), h(t)*x(t) + p(t)*y(t)) return "type7" def check_nonlinear_2eq_order1(eq, func, func_coef): t = list(list(eq[0].atoms(Derivative))[0].atoms(Symbol))[0] f = Wild('f') g = Wild('g') u, v = symbols('u, v', cls=Dummy) def check_type(x, y): r1 = eq[0].match(t*diff(x(t),t) - x(t) + f) r2 = eq[1].match(t*diff(y(t),t) - y(t) + g) if not (r1 and r2): r1 = eq[0].match(diff(x(t),t) - x(t)/t + f/t) r2 = eq[1].match(diff(y(t),t) - y(t)/t + g/t) if not (r1 and r2): r1 = (-eq[0]).match(t*diff(x(t),t) - x(t) + f) r2 = (-eq[1]).match(t*diff(y(t),t) - y(t) + g) if not (r1 and r2): r1 = (-eq[0]).match(diff(x(t),t) - x(t)/t + f/t) r2 = (-eq[1]).match(diff(y(t),t) - y(t)/t + g/t) if r1 and r2 and not (r1[f].subs(diff(x(t),t),u).subs(diff(y(t),t),v).has(t) \ or r2[g].subs(diff(x(t),t),u).subs(diff(y(t),t),v).has(t)): return 'type5' else: return None for func_ in func: if isinstance(func_, list): x = func[0][0].func y = func[0][1].func eq_type = check_type(x, y) if not eq_type: eq_type = check_type(y, x) return eq_type x = func[0].func y = func[1].func fc = func_coef n = Wild('n', exclude=[x(t),y(t)]) f1 = Wild('f1', exclude=[v,t]) f2 = Wild('f2', exclude=[v,t]) g1 = Wild('g1', exclude=[u,t]) g2 = Wild('g2', exclude=[u,t]) for i in range(2): eqs = 0 for terms in Add.make_args(eq[i]): eqs += terms/fc[i,func[i],1] eq[i] = eqs r = eq[0].match(diff(x(t),t) - x(t)**n*f) if r: g = (diff(y(t),t) - eq[1])/r[f] if r and not (g.has(x(t)) or g.subs(y(t),v).has(t) or r[f].subs(x(t),u).subs(y(t),v).has(t)): return 'type1' r = eq[0].match(diff(x(t),t) - exp(n*x(t))*f) if r: g = (diff(y(t),t) - eq[1])/r[f] if r and not (g.has(x(t)) or g.subs(y(t),v).has(t) or r[f].subs(x(t),u).subs(y(t),v).has(t)): return 'type2' g = Wild('g') r1 = eq[0].match(diff(x(t),t) - f) r2 = eq[1].match(diff(y(t),t) - g) if r1 and r2 and not (r1[f].subs(x(t),u).subs(y(t),v).has(t) or \ r2[g].subs(x(t),u).subs(y(t),v).has(t)): return 'type3' r1 = eq[0].match(diff(x(t),t) - f) r2 = eq[1].match(diff(y(t),t) - g) num, den = ( (r1[f].subs(x(t),u).subs(y(t),v))/ (r2[g].subs(x(t),u).subs(y(t),v))).as_numer_denom() R1 = num.match(f1*g1) R2 = den.match(f2*g2) # phi = (r1[f].subs(x(t),u).subs(y(t),v))/num if R1 and R2: return 'type4' return None def check_nonlinear_2eq_order2(eq, func, func_coef): return None def check_nonlinear_3eq_order1(eq, func, func_coef): x = func[0].func y = func[1].func z = func[2].func fc = func_coef t = list(list(eq[0].atoms(Derivative))[0].atoms(Symbol))[0] u, v, w = symbols('u, v, w', cls=Dummy) a = Wild('a', exclude=[x(t), y(t), z(t), t]) b = Wild('b', exclude=[x(t), y(t), z(t), t]) c = Wild('c', exclude=[x(t), y(t), z(t), t]) f = Wild('f') F1 = Wild('F1') F2 = Wild('F2') F3 = Wild('F3') for i in range(3): eqs = 0 for terms in Add.make_args(eq[i]): eqs += terms/fc[i,func[i],1] eq[i] = eqs r1 = eq[0].match(diff(x(t),t) - a*y(t)*z(t)) r2 = eq[1].match(diff(y(t),t) - b*z(t)*x(t)) r3 = eq[2].match(diff(z(t),t) - c*x(t)*y(t)) if r1 and r2 and r3: num1, den1 = r1[a].as_numer_denom() num2, den2 = r2[b].as_numer_denom() num3, den3 = r3[c].as_numer_denom() if solve([num1*u-den1*(v-w), num2*v-den2*(w-u), num3*w-den3*(u-v)],[u, v]): return 'type1' r = eq[0].match(diff(x(t),t) - y(t)*z(t)*f) if r: r1 = collect_const(r[f]).match(a*f) r2 = ((diff(y(t),t) - eq[1])/r1[f]).match(b*z(t)*x(t)) r3 = ((diff(z(t),t) - eq[2])/r1[f]).match(c*x(t)*y(t)) if r1 and r2 and r3: num1, den1 = r1[a].as_numer_denom() num2, den2 = r2[b].as_numer_denom() num3, den3 = r3[c].as_numer_denom() if solve([num1*u-den1*(v-w), num2*v-den2*(w-u), num3*w-den3*(u-v)],[u, v]): return 'type2' r = eq[0].match(diff(x(t),t) - (F2-F3)) if r: r1 = collect_const(r[F2]).match(c*F2) r1.update(collect_const(r[F3]).match(b*F3)) if r1: if eq[1].has(r1[F2]) and not eq[1].has(r1[F3]): r1[F2], r1[F3] = r1[F3], r1[F2] r1[c], r1[b] = -r1[b], -r1[c] r2 = eq[1].match(diff(y(t),t) - a*r1[F3] + r1[c]*F1) if r2: r3 = (eq[2] == diff(z(t),t) - r1[b]*r2[F1] + r2[a]*r1[F2]) if r1 and r2 and r3: return 'type3' r = eq[0].match(diff(x(t),t) - z(t)*F2 + y(t)*F3) if r: r1 = collect_const(r[F2]).match(c*F2) r1.update(collect_const(r[F3]).match(b*F3)) if r1: if eq[1].has(r1[F2]) and not eq[1].has(r1[F3]): r1[F2], r1[F3] = r1[F3], r1[F2] r1[c], r1[b] = -r1[b], -r1[c] r2 = (diff(y(t),t) - eq[1]).match(a*x(t)*r1[F3] - r1[c]*z(t)*F1) if r2: r3 = (diff(z(t),t) - eq[2] == r1[b]*y(t)*r2[F1] - r2[a]*x(t)*r1[F2]) if r1 and r2 and r3: return 'type4' r = (diff(x(t),t) - eq[0]).match(x(t)*(F2 - F3)) if r: r1 = collect_const(r[F2]).match(c*F2) r1.update(collect_const(r[F3]).match(b*F3)) if r1: if eq[1].has(r1[F2]) and not eq[1].has(r1[F3]): r1[F2], r1[F3] = r1[F3], r1[F2] r1[c], r1[b] = -r1[b], -r1[c] r2 = (diff(y(t),t) - eq[1]).match(y(t)*(a*r1[F3] - r1[c]*F1)) if r2: r3 = (diff(z(t),t) - eq[2] == z(t)*(r1[b]*r2[F1] - r2[a]*r1[F2])) if r1 and r2 and r3: return 'type5' return None def check_nonlinear_3eq_order2(eq, func, func_coef): return None @vectorize(0) def odesimp(ode, eq, func, hint): r""" Simplifies solutions of ODEs, including trying to solve for ``func`` and running :py:meth:`~sympy.solvers.ode.constantsimp`. It may use knowledge of the type of solution that the hint returns to apply additional simplifications. It also attempts to integrate any :py:class:`~sympy.integrals.integrals.Integral`\s in the expression, if the hint is not an ``_Integral`` hint. This function should have no effect on expressions returned by :py:meth:`~sympy.solvers.ode.dsolve`, as :py:meth:`~sympy.solvers.ode.dsolve` already calls :py:meth:`~sympy.solvers.ode.ode.odesimp`, but the individual hint functions do not call :py:meth:`~sympy.solvers.ode.ode.odesimp` (because the :py:meth:`~sympy.solvers.ode.dsolve` wrapper does). Therefore, this function is designed for mainly internal use. Examples ======== >>> from sympy import sin, symbols, dsolve, pprint, Function >>> from sympy.solvers.ode.ode import odesimp >>> x , u2, C1= symbols('x,u2,C1') >>> f = Function('f') >>> eq = dsolve(x*f(x).diff(x) - f(x) - x*sin(f(x)/x), f(x), ... hint='1st_homogeneous_coeff_subs_indep_div_dep_Integral', ... simplify=False) >>> pprint(eq, wrap_line=False) x ---- f(x) / | | / 1 \ | -|u1 + -------| | | /1 \| | | sin|--|| | \ \u1// log(f(x)) = log(C1) + | ---------------- d(u1) | 2 | u1 | / >>> pprint(odesimp(eq, f(x), 1, {C1}, ... hint='1st_homogeneous_coeff_subs_indep_div_dep' ... )) #doctest: +SKIP x --------- = C1 /f(x)\ tan|----| \2*x / """ x = func.args[0] f = func.func C1 = get_numbered_constants(eq, num=1) constants = eq.free_symbols - ode.free_symbols # First, integrate if the hint allows it. eq = _handle_Integral(eq, func, hint) if hint.startswith("nth_linear_euler_eq_nonhomogeneous"): eq = simplify(eq) if not isinstance(eq, Equality): raise TypeError("eq should be an instance of Equality") # Second, clean up the arbitrary constants. # Right now, nth linear hints can put as many as 2*order constants in an # expression. If that number grows with another hint, the third argument # here should be raised accordingly, or constantsimp() rewritten to handle # an arbitrary number of constants. eq = constantsimp(eq, constants) # Lastly, now that we have cleaned up the expression, try solving for func. # When CRootOf is implemented in solve(), we will want to return a CRootOf # every time instead of an Equality. # Get the f(x) on the left if possible. if eq.rhs == func and not eq.lhs.has(func): eq = [Eq(eq.rhs, eq.lhs)] # make sure we are working with lists of solutions in simplified form. if eq.lhs == func and not eq.rhs.has(func): # The solution is already solved eq = [eq] # special simplification of the rhs if hint.startswith("nth_linear_constant_coeff"): # Collect terms to make the solution look nice. # This is also necessary for constantsimp to remove unnecessary # terms from the particular solution from variation of parameters # # Collect is not behaving reliably here. The results for # some linear constant-coefficient equations with repeated # roots do not properly simplify all constants sometimes. # 'collectterms' gives different orders sometimes, and results # differ in collect based on that order. The # sort-reverse trick fixes things, but may fail in the # future. In addition, collect is splitting exponentials with # rational powers for no reason. We have to do a match # to fix this using Wilds. # # XXX: This global collectterms hack should be removed. global collectterms collectterms.sort(key=default_sort_key) collectterms.reverse() assert len(eq) == 1 and eq[0].lhs == f(x) sol = eq[0].rhs sol = expand_mul(sol) for i, reroot, imroot in collectterms: sol = collect(sol, x**i*exp(reroot*x)*sin(abs(imroot)*x)) sol = collect(sol, x**i*exp(reroot*x)*cos(imroot*x)) for i, reroot, imroot in collectterms: sol = collect(sol, x**i*exp(reroot*x)) del collectterms # Collect is splitting exponentials with rational powers for # no reason. We call powsimp to fix. sol = powsimp(sol) eq[0] = Eq(f(x), sol) else: # The solution is not solved, so try to solve it try: floats = any(i.is_Float for i in eq.atoms(Number)) eqsol = solve(eq, func, force=True, rational=False if floats else None) if not eqsol: raise NotImplementedError except (NotImplementedError, PolynomialError): eq = [eq] else: def _expand(expr): numer, denom = expr.as_numer_denom() if denom.is_Add: return expr else: return powsimp(expr.expand(), combine='exp', deep=True) # XXX: the rest of odesimp() expects each ``t`` to be in a # specific normal form: rational expression with numerator # expanded, but with combined exponential functions (at # least in this setup all tests pass). eq = [Eq(f(x), _expand(t)) for t in eqsol] # special simplification of the lhs. if hint.startswith("1st_homogeneous_coeff"): for j, eqi in enumerate(eq): newi = logcombine(eqi, force=True) if isinstance(newi.lhs, log) and newi.rhs == 0: newi = Eq(newi.lhs.args[0]/C1, C1) eq[j] = newi # We cleaned up the constants before solving to help the solve engine with # a simpler expression, but the solved expression could have introduced # things like -C1, so rerun constantsimp() one last time before returning. for i, eqi in enumerate(eq): eq[i] = constantsimp(eqi, constants) eq[i] = constant_renumber(eq[i], ode.free_symbols) # If there is only 1 solution, return it; # otherwise return the list of solutions. if len(eq) == 1: eq = eq[0] return eq def ode_sol_simplicity(sol, func, trysolving=True): r""" Returns an extended integer representing how simple a solution to an ODE is. The following things are considered, in order from most simple to least: - ``sol`` is solved for ``func``. - ``sol`` is not solved for ``func``, but can be if passed to solve (e.g., a solution returned by ``dsolve(ode, func, simplify=False``). - If ``sol`` is not solved for ``func``, then base the result on the length of ``sol``, as computed by ``len(str(sol))``. - If ``sol`` has any unevaluated :py:class:`~sympy.integrals.integrals.Integral`\s, this will automatically be considered less simple than any of the above. This function returns an integer such that if solution A is simpler than solution B by above metric, then ``ode_sol_simplicity(sola, func) < ode_sol_simplicity(solb, func)``. Currently, the following are the numbers returned, but if the heuristic is ever improved, this may change. Only the ordering is guaranteed. +----------------------------------------------+-------------------+ | Simplicity | Return | +==============================================+===================+ | ``sol`` solved for ``func`` | ``-2`` | +----------------------------------------------+-------------------+ | ``sol`` not solved for ``func`` but can be | ``-1`` | +----------------------------------------------+-------------------+ | ``sol`` is not solved nor solvable for | ``len(str(sol))`` | | ``func`` | | +----------------------------------------------+-------------------+ | ``sol`` contains an | ``oo`` | | :obj:`~sympy.integrals.integrals.Integral` | | +----------------------------------------------+-------------------+ ``oo`` here means the SymPy infinity, which should compare greater than any integer. If you already know :py:meth:`~sympy.solvers.solvers.solve` cannot solve ``sol``, you can use ``trysolving=False`` to skip that step, which is the only potentially slow step. For example, :py:meth:`~sympy.solvers.ode.dsolve` with the ``simplify=False`` flag should do this. If ``sol`` is a list of solutions, if the worst solution in the list returns ``oo`` it returns that, otherwise it returns ``len(str(sol))``, that is, the length of the string representation of the whole list. Examples ======== This function is designed to be passed to ``min`` as the key argument, such as ``min(listofsolutions, key=lambda i: ode_sol_simplicity(i, f(x)))``. >>> from sympy import symbols, Function, Eq, tan, Integral >>> from sympy.solvers.ode.ode import ode_sol_simplicity >>> x, C1, C2 = symbols('x, C1, C2') >>> f = Function('f') >>> ode_sol_simplicity(Eq(f(x), C1*x**2), f(x)) -2 >>> ode_sol_simplicity(Eq(x**2 + f(x), C1), f(x)) -1 >>> ode_sol_simplicity(Eq(f(x), C1*Integral(2*x, x)), f(x)) oo >>> eq1 = Eq(f(x)/tan(f(x)/(2*x)), C1) >>> eq2 = Eq(f(x)/tan(f(x)/(2*x) + f(x)), C2) >>> [ode_sol_simplicity(eq, f(x)) for eq in [eq1, eq2]] [28, 35] >>> min([eq1, eq2], key=lambda i: ode_sol_simplicity(i, f(x))) Eq(f(x)/tan(f(x)/(2*x)), C1) """ # TODO: if two solutions are solved for f(x), we still want to be # able to get the simpler of the two # See the docstring for the coercion rules. We check easier (faster) # things here first, to save time. if iterable(sol): # See if there are Integrals for i in sol: if ode_sol_simplicity(i, func, trysolving=trysolving) == oo: return oo return len(str(sol)) if sol.has(Integral): return oo # Next, try to solve for func. This code will change slightly when CRootOf # is implemented in solve(). Probably a CRootOf solution should fall # somewhere between a normal solution and an unsolvable expression. # First, see if they are already solved if sol.lhs == func and not sol.rhs.has(func) or \ sol.rhs == func and not sol.lhs.has(func): return -2 # We are not so lucky, try solving manually if trysolving: try: sols = solve(sol, func) if not sols: raise NotImplementedError except NotImplementedError: pass else: return -1 # Finally, a naive computation based on the length of the string version # of the expression. This may favor combined fractions because they # will not have duplicate denominators, and may slightly favor expressions # with fewer additions and subtractions, as those are separated by spaces # by the printer. # Additional ideas for simplicity heuristics are welcome, like maybe # checking if a equation has a larger domain, or if constantsimp has # introduced arbitrary constants numbered higher than the order of a # given ODE that sol is a solution of. return len(str(sol)) def _extract_funcs(eqs): from sympy.core.basic import preorder_traversal funcs = [] for eq in eqs: derivs = [node for node in preorder_traversal(eq) if isinstance(node, Derivative)] func = [] for d in derivs: func += list(d.atoms(AppliedUndef)) for func_ in func: funcs.append(func_) funcs = list(uniq(funcs)) return funcs def _get_constant_subexpressions(expr, Cs): Cs = set(Cs) Ces = [] def _recursive_walk(expr): expr_syms = expr.free_symbols if expr_syms and expr_syms.issubset(Cs): Ces.append(expr) else: if expr.func == exp: expr = expr.expand(mul=True) if expr.func in (Add, Mul): d = sift(expr.args, lambda i : i.free_symbols.issubset(Cs)) if len(d[True]) > 1: x = expr.func(*d[True]) if not x.is_number: Ces.append(x) elif isinstance(expr, Integral): if expr.free_symbols.issubset(Cs) and \ all(len(x) == 3 for x in expr.limits): Ces.append(expr) for i in expr.args: _recursive_walk(i) return _recursive_walk(expr) return Ces def __remove_linear_redundancies(expr, Cs): cnts = {i: expr.count(i) for i in Cs} Cs = [i for i in Cs if cnts[i] > 0] def _linear(expr): if isinstance(expr, Add): xs = [i for i in Cs if expr.count(i)==cnts[i] \ and 0 == expr.diff(i, 2)] d = {} for x in xs: y = expr.diff(x) if y not in d: d[y]=[] d[y].append(x) for y in d: if len(d[y]) > 1: d[y].sort(key=str) for x in d[y][1:]: expr = expr.subs(x, 0) return expr def _recursive_walk(expr): if len(expr.args) != 0: expr = expr.func(*[_recursive_walk(i) for i in expr.args]) expr = _linear(expr) return expr if isinstance(expr, Equality): lhs, rhs = [_recursive_walk(i) for i in expr.args] f = lambda i: isinstance(i, Number) or i in Cs if isinstance(lhs, Symbol) and lhs in Cs: rhs, lhs = lhs, rhs if lhs.func in (Add, Symbol) and rhs.func in (Add, Symbol): dlhs = sift([lhs] if isinstance(lhs, AtomicExpr) else lhs.args, f) drhs = sift([rhs] if isinstance(rhs, AtomicExpr) else rhs.args, f) for i in [True, False]: for hs in [dlhs, drhs]: if i not in hs: hs[i] = [0] # this calculation can be simplified lhs = Add(*dlhs[False]) - Add(*drhs[False]) rhs = Add(*drhs[True]) - Add(*dlhs[True]) elif lhs.func in (Mul, Symbol) and rhs.func in (Mul, Symbol): dlhs = sift([lhs] if isinstance(lhs, AtomicExpr) else lhs.args, f) if True in dlhs: if False not in dlhs: dlhs[False] = [1] lhs = Mul(*dlhs[False]) rhs = rhs/Mul(*dlhs[True]) return Eq(lhs, rhs) else: return _recursive_walk(expr) @vectorize(0) def constantsimp(expr, constants): r""" Simplifies an expression with arbitrary constants in it. This function is written specifically to work with :py:meth:`~sympy.solvers.ode.dsolve`, and is not intended for general use. Simplification is done by "absorbing" the arbitrary constants into other arbitrary constants, numbers, and symbols that they are not independent of. The symbols must all have the same name with numbers after it, for example, ``C1``, ``C2``, ``C3``. The ``symbolname`` here would be '``C``', the ``startnumber`` would be 1, and the ``endnumber`` would be 3. If the arbitrary constants are independent of the variable ``x``, then the independent symbol would be ``x``. There is no need to specify the dependent function, such as ``f(x)``, because it already has the independent symbol, ``x``, in it. Because terms are "absorbed" into arbitrary constants and because constants are renumbered after simplifying, the arbitrary constants in expr are not necessarily equal to the ones of the same name in the returned result. If two or more arbitrary constants are added, multiplied, or raised to the power of each other, they are first absorbed together into a single arbitrary constant. Then the new constant is combined into other terms if necessary. Absorption of constants is done with limited assistance: 1. terms of :py:class:`~sympy.core.add.Add`\s are collected to try join constants so `e^x (C_1 \cos(x) + C_2 \cos(x))` will simplify to `e^x C_1 \cos(x)`; 2. powers with exponents that are :py:class:`~sympy.core.add.Add`\s are expanded so `e^{C_1 + x}` will be simplified to `C_1 e^x`. Use :py:meth:`~sympy.solvers.ode.ode.constant_renumber` to renumber constants after simplification or else arbitrary numbers on constants may appear, e.g. `C_1 + C_3 x`. In rare cases, a single constant can be "simplified" into two constants. Every differential equation solution should have as many arbitrary constants as the order of the differential equation. The result here will be technically correct, but it may, for example, have `C_1` and `C_2` in an expression, when `C_1` is actually equal to `C_2`. Use your discretion in such situations, and also take advantage of the ability to use hints in :py:meth:`~sympy.solvers.ode.dsolve`. Examples ======== >>> from sympy import symbols >>> from sympy.solvers.ode.ode import constantsimp >>> C1, C2, C3, x, y = symbols('C1, C2, C3, x, y') >>> constantsimp(2*C1*x, {C1, C2, C3}) C1*x >>> constantsimp(C1 + 2 + x, {C1, C2, C3}) C1 + x >>> constantsimp(C1*C2 + 2 + C2 + C3*x, {C1, C2, C3}) C1 + C3*x """ # This function works recursively. The idea is that, for Mul, # Add, Pow, and Function, if the class has a constant in it, then # we can simplify it, which we do by recursing down and # simplifying up. Otherwise, we can skip that part of the # expression. Cs = constants orig_expr = expr constant_subexprs = _get_constant_subexpressions(expr, Cs) for xe in constant_subexprs: xes = list(xe.free_symbols) if not xes: continue if all([expr.count(c) == xe.count(c) for c in xes]): xes.sort(key=str) expr = expr.subs(xe, xes[0]) # try to perform common sub-expression elimination of constant terms try: commons, rexpr = cse(expr) commons.reverse() rexpr = rexpr[0] for s in commons: cs = list(s[1].atoms(Symbol)) if len(cs) == 1 and cs[0] in Cs and \ cs[0] not in rexpr.atoms(Symbol) and \ not any(cs[0] in ex for ex in commons if ex != s): rexpr = rexpr.subs(s[0], cs[0]) else: rexpr = rexpr.subs(*s) expr = rexpr except IndexError: pass expr = __remove_linear_redundancies(expr, Cs) def _conditional_term_factoring(expr): new_expr = terms_gcd(expr, clear=False, deep=True, expand=False) # we do not want to factor exponentials, so handle this separately if new_expr.is_Mul: infac = False asfac = False for m in new_expr.args: if isinstance(m, exp): asfac = True elif m.is_Add: infac = any(isinstance(fi, exp) for t in m.args for fi in Mul.make_args(t)) if asfac and infac: new_expr = expr break return new_expr expr = _conditional_term_factoring(expr) # call recursively if more simplification is possible if orig_expr != expr: return constantsimp(expr, Cs) return expr def constant_renumber(expr, variables=None, newconstants=None): r""" Renumber arbitrary constants in ``expr`` to use the symbol names as given in ``newconstants``. In the process, this reorders expression terms in a standard way. If ``newconstants`` is not provided then the new constant names will be ``C1``, ``C2`` etc. Otherwise ``newconstants`` should be an iterable giving the new symbols to use for the constants in order. The ``variables`` argument is a list of non-constant symbols. All other free symbols found in ``expr`` are assumed to be constants and will be renumbered. If ``variables`` is not given then any numbered symbol beginning with ``C`` (e.g. ``C1``) is assumed to be a constant. Symbols are renumbered based on ``.sort_key()``, so they should be numbered roughly in the order that they appear in the final, printed expression. Note that this ordering is based in part on hashes, so it can produce different results on different machines. The structure of this function is very similar to that of :py:meth:`~sympy.solvers.ode.constantsimp`. Examples ======== >>> from sympy import symbols >>> from sympy.solvers.ode.ode import constant_renumber >>> x, C1, C2, C3 = symbols('x,C1:4') >>> expr = C3 + C2*x + C1*x**2 >>> expr C1*x**2 + C2*x + C3 >>> constant_renumber(expr) C1 + C2*x + C3*x**2 The ``variables`` argument specifies which are constants so that the other symbols will not be renumbered: >>> constant_renumber(expr, [C1, x]) C1*x**2 + C2 + C3*x The ``newconstants`` argument is used to specify what symbols to use when replacing the constants: >>> constant_renumber(expr, [x], newconstants=symbols('E1:4')) E1 + E2*x + E3*x**2 """ # System of expressions if isinstance(expr, (set, list, tuple)): return type(expr)(constant_renumber(Tuple(*expr), variables=variables, newconstants=newconstants)) # Symbols in solution but not ODE are constants if variables is not None: variables = set(variables) free_symbols = expr.free_symbols constantsymbols = list(free_symbols - variables) # Any Cn is a constant... else: variables = set() isconstant = lambda s: s.startswith('C') and s[1:].isdigit() constantsymbols = [sym for sym in expr.free_symbols if isconstant(sym.name)] # Find new constants checking that they aren't already in the ODE if newconstants is None: iter_constants = numbered_symbols(start=1, prefix='C', exclude=variables) else: iter_constants = (sym for sym in newconstants if sym not in variables) constants_found = [] # make a mapping to send all constantsymbols to S.One and use # that to make sure that term ordering is not dependent on # the indexed value of C C_1 = [(ci, S.One) for ci in constantsymbols] sort_key=lambda arg: default_sort_key(arg.subs(C_1)) def _constant_renumber(expr): r""" We need to have an internal recursive function """ # For system of expressions if isinstance(expr, Tuple): renumbered = [_constant_renumber(e) for e in expr] return Tuple(*renumbered) if isinstance(expr, Equality): return Eq( _constant_renumber(expr.lhs), _constant_renumber(expr.rhs)) if type(expr) not in (Mul, Add, Pow) and not expr.is_Function and \ not expr.has(*constantsymbols): # Base case, as above. Hope there aren't constants inside # of some other class, because they won't be renumbered. return expr elif expr.is_Piecewise: return expr elif expr in constantsymbols: if expr not in constants_found: constants_found.append(expr) return expr elif expr.is_Function or expr.is_Pow: return expr.func( *[_constant_renumber(x) for x in expr.args]) else: sortedargs = list(expr.args) sortedargs.sort(key=sort_key) return expr.func(*[_constant_renumber(x) for x in sortedargs]) expr = _constant_renumber(expr) # Don't renumber symbols present in the ODE. constants_found = [c for c in constants_found if c not in variables] # Renumbering happens here subs_dict = {var: cons for var, cons in zip(constants_found, iter_constants)} expr = expr.subs(subs_dict, simultaneous=True) return expr def _handle_Integral(expr, func, hint): r""" Converts a solution with Integrals in it into an actual solution. For most hints, this simply runs ``expr.doit()``. """ if hint == "nth_linear_constant_coeff_homogeneous": sol = expr elif not hint.endswith("_Integral"): sol = expr.doit() else: sol = expr return sol # XXX: Should this function maybe go somewhere else? def homogeneous_order(eq, *symbols): r""" Returns the order `n` if `g` is homogeneous and ``None`` if it is not homogeneous. Determines if a function is homogeneous and if so of what order. A function `f(x, y, \cdots)` is homogeneous of order `n` if `f(t x, t y, \cdots) = t^n f(x, y, \cdots)`. If the function is of two variables, `F(x, y)`, then `f` being homogeneous of any order is equivalent to being able to rewrite `F(x, y)` as `G(x/y)` or `H(y/x)`. This fact is used to solve 1st order ordinary differential equations whose coefficients are homogeneous of the same order (see the docstrings of :obj:`~sympy.solvers.ode.single.HomogeneousCoeffSubsDepDivIndep` and :obj:`~sympy.solvers.ode.single.HomogeneousCoeffSubsIndepDivDep`). Symbols can be functions, but every argument of the function must be a symbol, and the arguments of the function that appear in the expression must match those given in the list of symbols. If a declared function appears with different arguments than given in the list of symbols, ``None`` is returned. Examples ======== >>> from sympy import Function, homogeneous_order, sqrt >>> from sympy.abc import x, y >>> f = Function('f') >>> homogeneous_order(f(x), f(x)) is None True >>> homogeneous_order(f(x,y), f(y, x), x, y) is None True >>> homogeneous_order(f(x), f(x), x) 1 >>> homogeneous_order(x**2*f(x)/sqrt(x**2+f(x)**2), x, f(x)) 2 >>> homogeneous_order(x**2+f(x), x, f(x)) is None True """ if not symbols: raise ValueError("homogeneous_order: no symbols were given.") symset = set(symbols) eq = sympify(eq) # The following are not supported if eq.has(Order, Derivative): return None # These are all constants if (eq.is_Number or eq.is_NumberSymbol or eq.is_number ): return S.Zero # Replace all functions with dummy variables dum = numbered_symbols(prefix='d', cls=Dummy) newsyms = set() for i in [j for j in symset if getattr(j, 'is_Function')]: iargs = set(i.args) if iargs.difference(symset): return None else: dummyvar = next(dum) eq = eq.subs(i, dummyvar) symset.remove(i) newsyms.add(dummyvar) symset.update(newsyms) if not eq.free_symbols & symset: return None # assuming order of a nested function can only be equal to zero if isinstance(eq, Function): return None if homogeneous_order( eq.args[0], *tuple(symset)) != 0 else S.Zero # make the replacement of x with x*t and see if t can be factored out t = Dummy('t', positive=True) # It is sufficient that t > 0 eqs = separatevars(eq.subs([(i, t*i) for i in symset]), [t], dict=True)[t] if eqs is S.One: return S.Zero # there was no term with only t i, d = eqs.as_independent(t, as_Add=False) b, e = d.as_base_exp() if b == t: return e def ode_2nd_power_series_ordinary(eq, func, order, match): r""" Gives a power series solution to a second order homogeneous differential equation with polynomial coefficients at an ordinary point. A homogeneous differential equation is of the form .. math :: P(x)\frac{d^2y}{dx^2} + Q(x)\frac{dy}{dx} + R(x) = 0 For simplicity it is assumed that `P(x)`, `Q(x)` and `R(x)` are polynomials, it is sufficient that `\frac{Q(x)}{P(x)}` and `\frac{R(x)}{P(x)}` exists at `x_{0}`. A recurrence relation is obtained by substituting `y` as `\sum_{n=0}^\infty a_{n}x^{n}`, in the differential equation, and equating the nth term. Using this relation various terms can be generated. Examples ======== >>> from sympy import dsolve, Function, pprint >>> from sympy.abc import x >>> f = Function("f") >>> eq = f(x).diff(x, 2) + f(x) >>> pprint(dsolve(eq, hint='2nd_power_series_ordinary')) / 4 2 \ / 2\ |x x | | x | / 6\ f(x) = C2*|-- - -- + 1| + C1*x*|1 - --| + O\x / \24 2 / \ 6 / References ========== - http://tutorial.math.lamar.edu/Classes/DE/SeriesSolutions.aspx - George E. Simmons, "Differential Equations with Applications and Historical Notes", p.p 176 - 184 """ x = func.args[0] f = func.func C0, C1 = get_numbered_constants(eq, num=2) n = Dummy("n", integer=True) s = Wild("s") k = Wild("k", exclude=[x]) x0 = match.get('x0') terms = match.get('terms', 5) p = match[match['a3']] q = match[match['b3']] r = match[match['c3']] seriesdict = {} recurr = Function("r") # Generating the recurrence relation which works this way: # for the second order term the summation begins at n = 2. The coefficients # p is multiplied with an*(n - 1)*(n - 2)*x**n-2 and a substitution is made such that # the exponent of x becomes n. # For example, if p is x, then the second degree recurrence term is # an*(n - 1)*(n - 2)*x**n-1, substituting (n - 1) as n, it transforms to # an+1*n*(n - 1)*x**n. # A similar process is done with the first order and zeroth order term. coefflist = [(recurr(n), r), (n*recurr(n), q), (n*(n - 1)*recurr(n), p)] for index, coeff in enumerate(coefflist): if coeff[1]: f2 = powsimp(expand((coeff[1]*(x - x0)**(n - index)).subs(x, x + x0))) if f2.is_Add: addargs = f2.args else: addargs = [f2] for arg in addargs: powm = arg.match(s*x**k) term = coeff[0]*powm[s] if not powm[k].is_Symbol: term = term.subs(n, n - powm[k].as_independent(n)[0]) startind = powm[k].subs(n, index) # Seeing if the startterm can be reduced further. # If it vanishes for n lesser than startind, it is # equal to summation from n. if startind: for i in reversed(range(startind)): if not term.subs(n, i): seriesdict[term] = i else: seriesdict[term] = i + 1 break else: seriesdict[term] = S.Zero # Stripping of terms so that the sum starts with the same number. teq = S.Zero suminit = seriesdict.values() rkeys = seriesdict.keys() req = Add(*rkeys) if any(suminit): maxval = max(suminit) for term in seriesdict: val = seriesdict[term] if val != maxval: for i in range(val, maxval): teq += term.subs(n, val) finaldict = {} if teq: fargs = teq.atoms(AppliedUndef) if len(fargs) == 1: finaldict[fargs.pop()] = 0 else: maxf = max(fargs, key = lambda x: x.args[0]) sol = solve(teq, maxf) if isinstance(sol, list): sol = sol[0] finaldict[maxf] = sol # Finding the recurrence relation in terms of the largest term. fargs = req.atoms(AppliedUndef) maxf = max(fargs, key = lambda x: x.args[0]) minf = min(fargs, key = lambda x: x.args[0]) if minf.args[0].is_Symbol: startiter = 0 else: startiter = -minf.args[0].as_independent(n)[0] lhs = maxf rhs = solve(req, maxf) if isinstance(rhs, list): rhs = rhs[0] # Checking how many values are already present tcounter = len([t for t in finaldict.values() if t]) for _ in range(tcounter, terms - 3): # Assuming c0 and c1 to be arbitrary check = rhs.subs(n, startiter) nlhs = lhs.subs(n, startiter) nrhs = check.subs(finaldict) finaldict[nlhs] = nrhs startiter += 1 # Post processing series = C0 + C1*(x - x0) for term in finaldict: if finaldict[term]: fact = term.args[0] series += (finaldict[term].subs([(recurr(0), C0), (recurr(1), C1)])*( x - x0)**fact) series = collect(expand_mul(series), [C0, C1]) + Order(x**terms) return Eq(f(x), series) def ode_2nd_linear_airy(eq, func, order, match): r""" Gives solution of the Airy differential equation .. math :: \frac{d^2y}{dx^2} + (a + b x) y(x) = 0 in terms of Airy special functions airyai and airybi. Examples ======== >>> from sympy import dsolve, Function >>> from sympy.abc import x >>> f = Function("f") >>> eq = f(x).diff(x, 2) - x*f(x) >>> dsolve(eq) Eq(f(x), C1*airyai(x) + C2*airybi(x)) """ x = func.args[0] f = func.func C0, C1 = get_numbered_constants(eq, num=2) b = match['b'] m = match['m'] if m.is_positive: arg = - b/cbrt(m)**2 - cbrt(m)*x elif m.is_negative: arg = - b/cbrt(-m)**2 + cbrt(-m)*x else: arg = - b/cbrt(-m)**2 + cbrt(-m)*x return Eq(f(x), C0*airyai(arg) + C1*airybi(arg)) def ode_2nd_power_series_regular(eq, func, order, match): r""" Gives a power series solution to a second order homogeneous differential equation with polynomial coefficients at a regular point. A second order homogeneous differential equation is of the form .. math :: P(x)\frac{d^2y}{dx^2} + Q(x)\frac{dy}{dx} + R(x) = 0 A point is said to regular singular at `x0` if `x - x0\frac{Q(x)}{P(x)}` and `(x - x0)^{2}\frac{R(x)}{P(x)}` are analytic at `x0`. For simplicity `P(x)`, `Q(x)` and `R(x)` are assumed to be polynomials. The algorithm for finding the power series solutions is: 1. Try expressing `(x - x0)P(x)` and `((x - x0)^{2})Q(x)` as power series solutions about x0. Find `p0` and `q0` which are the constants of the power series expansions. 2. Solve the indicial equation `f(m) = m(m - 1) + m*p0 + q0`, to obtain the roots `m1` and `m2` of the indicial equation. 3. If `m1 - m2` is a non integer there exists two series solutions. If `m1 = m2`, there exists only one solution. If `m1 - m2` is an integer, then the existence of one solution is confirmed. The other solution may or may not exist. The power series solution is of the form `x^{m}\sum_{n=0}^\infty a_{n}x^{n}`. The coefficients are determined by the following recurrence relation. `a_{n} = -\frac{\sum_{k=0}^{n-1} q_{n-k} + (m + k)p_{n-k}}{f(m + n)}`. For the case in which `m1 - m2` is an integer, it can be seen from the recurrence relation that for the lower root `m`, when `n` equals the difference of both the roots, the denominator becomes zero. So if the numerator is not equal to zero, a second series solution exists. Examples ======== >>> from sympy import dsolve, Function, pprint >>> from sympy.abc import x >>> f = Function("f") >>> eq = x*(f(x).diff(x, 2)) + 2*(f(x).diff(x)) + x*f(x) >>> pprint(dsolve(eq, hint='2nd_power_series_regular')) / 6 4 2 \ | x x x | / 4 2 \ C1*|- --- + -- - -- + 1| | x x | \ 720 24 2 / / 6\ f(x) = C2*|--- - -- + 1| + ------------------------ + O\x / \120 6 / x References ========== - George E. Simmons, "Differential Equations with Applications and Historical Notes", p.p 176 - 184 """ x = func.args[0] f = func.func C0, C1 = get_numbered_constants(eq, num=2) m = Dummy("m") # for solving the indicial equation x0 = match.get('x0') terms = match.get('terms', 5) p = match['p'] q = match['q'] # Generating the indicial equation indicial = [] for term in [p, q]: if not term.has(x): indicial.append(term) else: term = series(term, x=x, n=1, x0=x0) if isinstance(term, Order): indicial.append(S.Zero) else: for arg in term.args: if not arg.has(x): indicial.append(arg) break p0, q0 = indicial sollist = solve(m*(m - 1) + m*p0 + q0, m) if sollist and isinstance(sollist, list) and all( [sol.is_real for sol in sollist]): serdict1 = {} serdict2 = {} if len(sollist) == 1: # Only one series solution exists in this case. m1 = m2 = sollist.pop() if terms-m1-1 <= 0: return Eq(f(x), Order(terms)) serdict1 = _frobenius(terms-m1-1, m1, p0, q0, p, q, x0, x, C0) else: m1 = sollist[0] m2 = sollist[1] if m1 < m2: m1, m2 = m2, m1 # Irrespective of whether m1 - m2 is an integer or not, one # Frobenius series solution exists. serdict1 = _frobenius(terms-m1-1, m1, p0, q0, p, q, x0, x, C0) if not (m1 - m2).is_integer: # Second frobenius series solution exists. serdict2 = _frobenius(terms-m2-1, m2, p0, q0, p, q, x0, x, C1) else: # Check if second frobenius series solution exists. serdict2 = _frobenius(terms-m2-1, m2, p0, q0, p, q, x0, x, C1, check=m1) if serdict1: finalseries1 = C0 for key in serdict1: power = int(key.name[1:]) finalseries1 += serdict1[key]*(x - x0)**power finalseries1 = (x - x0)**m1*finalseries1 finalseries2 = S.Zero if serdict2: for key in serdict2: power = int(key.name[1:]) finalseries2 += serdict2[key]*(x - x0)**power finalseries2 += C1 finalseries2 = (x - x0)**m2*finalseries2 return Eq(f(x), collect(finalseries1 + finalseries2, [C0, C1]) + Order(x**terms)) def ode_2nd_linear_bessel(eq, func, order, match): r""" Gives solution of the Bessel differential equation .. math :: x^2 \frac{d^2y}{dx^2} + x \frac{dy}{dx} y(x) + (x^2-n^2) y(x) if n is integer then the solution is of the form Eq(f(x), C0 besselj(n,x) + C1 bessely(n,x)) as both the solutions are linearly independent else if n is a fraction then the solution is of the form Eq(f(x), C0 besselj(n,x) + C1 besselj(-n,x)) which can also transform into Eq(f(x), C0 besselj(n,x) + C1 bessely(n,x)). Examples ======== >>> from sympy.abc import x >>> from sympy import Symbol >>> v = Symbol('v', positive=True) >>> from sympy.solvers.ode import dsolve >>> from sympy import Function >>> f = Function('f') >>> y = f(x) >>> genform = x**2*y.diff(x, 2) + x*y.diff(x) + (x**2 - v**2)*y >>> dsolve(genform) Eq(f(x), C1*besselj(v, x) + C2*bessely(v, x)) References ========== https://www.math24.net/bessel-differential-equation/ """ x = func.args[0] f = func.func C0, C1 = get_numbered_constants(eq, num=2) n = match['n'] a4 = match['a4'] c4 = match['c4'] d4 = match['d4'] b4 = match['b4'] n = sqrt(n**2 + Rational(1, 4)*(c4 - 1)**2) return Eq(f(x), ((x**(Rational(1-c4,2)))*(C0*besselj(n/d4,a4*x**d4/d4) + C1*bessely(n/d4,a4*x**d4/d4))).subs(x, x-b4)) def _frobenius(n, m, p0, q0, p, q, x0, x, c, check=None): r""" Returns a dict with keys as coefficients and values as their values in terms of C0 """ n = int(n) # In cases where m1 - m2 is not an integer m2 = check d = Dummy("d") numsyms = numbered_symbols("C", start=0) numsyms = [next(numsyms) for i in range(n + 1)] serlist = [] for ser in [p, q]: # Order term not present if ser.is_polynomial(x) and Poly(ser, x).degree() <= n: if x0: ser = ser.subs(x, x + x0) dict_ = Poly(ser, x).as_dict() # Order term present else: tseries = series(ser, x=x0, n=n+1) # Removing order dict_ = Poly(list(ordered(tseries.args))[: -1], x).as_dict() # Fill in with zeros, if coefficients are zero. for i in range(n + 1): if (i,) not in dict_: dict_[(i,)] = S.Zero serlist.append(dict_) pseries = serlist[0] qseries = serlist[1] indicial = d*(d - 1) + d*p0 + q0 frobdict = {} for i in range(1, n + 1): num = c*(m*pseries[(i,)] + qseries[(i,)]) for j in range(1, i): sym = Symbol("C" + str(j)) num += frobdict[sym]*((m + j)*pseries[(i - j,)] + qseries[(i - j,)]) # Checking for cases when m1 - m2 is an integer. If num equals zero # then a second Frobenius series solution cannot be found. If num is not zero # then set constant as zero and proceed. if m2 is not None and i == m2 - m: if num: return False else: frobdict[numsyms[i]] = S.Zero else: frobdict[numsyms[i]] = -num/(indicial.subs(d, m+i)) return frobdict def _nth_order_reducible_match(eq, func): r""" Matches any differential equation that can be rewritten with a smaller order. Only derivatives of ``func`` alone, wrt a single variable, are considered, and only in them should ``func`` appear. """ # ODE only handles functions of 1 variable so this affirms that state assert len(func.args) == 1 x = func.args[0] vc = [d.variable_count[0] for d in eq.atoms(Derivative) if d.expr == func and len(d.variable_count) == 1] ords = [c for v, c in vc if v == x] if len(ords) < 2: return smallest = min(ords) # make sure func does not appear outside of derivatives D = Dummy() if eq.subs(func.diff(x, smallest), D).has(func): return return {'n': smallest} def ode_nth_order_reducible(eq, func, order, match): r""" Solves ODEs that only involve derivatives of the dependent variable using a substitution of the form `f^n(x) = g(x)`. For example any second order ODE of the form `f''(x) = h(f'(x), x)` can be transformed into a pair of 1st order ODEs `g'(x) = h(g(x), x)` and `f'(x) = g(x)`. Usually the 1st order ODE for `g` is easier to solve. If that gives an explicit solution for `g` then `f` is found simply by integration. Examples ======== >>> from sympy import Function, dsolve, Eq >>> from sympy.abc import x >>> f = Function('f') >>> eq = Eq(x*f(x).diff(x)**2 + f(x).diff(x, 2), 0) >>> dsolve(eq, f(x), hint='nth_order_reducible') ... # doctest: +NORMALIZE_WHITESPACE Eq(f(x), C1 - sqrt(-1/C2)*log(-C2*sqrt(-1/C2) + x) + sqrt(-1/C2)*log(C2*sqrt(-1/C2) + x)) """ x = func.args[0] f = func.func n = match['n'] # get a unique function name for g names = [a.name for a in eq.atoms(AppliedUndef)] while True: name = Dummy().name if name not in names: g = Function(name) break w = f(x).diff(x, n) geq = eq.subs(w, g(x)) gsol = dsolve(geq, g(x)) if not isinstance(gsol, list): gsol = [gsol] # Might be multiple solutions to the reduced ODE: fsol = [] for gsoli in gsol: fsoli = dsolve(gsoli.subs(g(x), w), f(x)) # or do integration n times fsol.append(fsoli) if len(fsol) == 1: fsol = fsol[0] return fsol def _remove_redundant_solutions(eq, solns, order, var): r""" Remove redundant solutions from the set of solutions. This function is needed because otherwise dsolve can return redundant solutions. As an example consider: eq = Eq((f(x).diff(x, 2))*f(x).diff(x), 0) There are two ways to find solutions to eq. The first is to solve f(x).diff(x, 2) = 0 leading to solution f(x)=C1 + C2*x. The second is to solve the equation f(x).diff(x) = 0 leading to the solution f(x) = C1. In this particular case we then see that the second solution is a special case of the first and we don't want to return it. This does not always happen. If we have eq = Eq((f(x)**2-4)*(f(x).diff(x)-4), 0) then we get the algebraic solution f(x) = [-2, 2] and the integral solution f(x) = x + C1 and in this case the two solutions are not equivalent wrt initial conditions so both should be returned. """ def is_special_case_of(soln1, soln2): return _is_special_case_of(soln1, soln2, eq, order, var) unique_solns = [] for soln1 in solns: for soln2 in unique_solns[:]: if is_special_case_of(soln1, soln2): break elif is_special_case_of(soln2, soln1): unique_solns.remove(soln2) else: unique_solns.append(soln1) return unique_solns def _is_special_case_of(soln1, soln2, eq, order, var): r""" True if soln1 is found to be a special case of soln2 wrt some value of the constants that appear in soln2. False otherwise. """ # The solutions returned by dsolve may be given explicitly or implicitly. # We will equate the sol1=(soln1.rhs - soln1.lhs), sol2=(soln2.rhs - soln2.lhs) # of the two solutions. # # Since this is supposed to hold for all x it also holds for derivatives. # For an order n ode we should be able to differentiate # each solution n times to get n+1 equations. # # We then try to solve those n+1 equations for the integrations constants # in sol2. If we can find a solution that doesn't depend on x then it # means that some value of the constants in sol1 is a special case of # sol2 corresponding to a particular choice of the integration constants. # In case the solution is in implicit form we subtract the sides soln1 = soln1.rhs - soln1.lhs soln2 = soln2.rhs - soln2.lhs # Work for the series solution if soln1.has(Order) and soln2.has(Order): if soln1.getO() == soln2.getO(): soln1 = soln1.removeO() soln2 = soln2.removeO() else: return False elif soln1.has(Order) or soln2.has(Order): return False constants1 = soln1.free_symbols.difference(eq.free_symbols) constants2 = soln2.free_symbols.difference(eq.free_symbols) constants1_new = get_numbered_constants(Tuple(soln1, soln2), len(constants1)) if len(constants1) == 1: constants1_new = {constants1_new} for c_old, c_new in zip(constants1, constants1_new): soln1 = soln1.subs(c_old, c_new) # n equations for sol1 = sol2, sol1'=sol2', ... lhs = soln1 rhs = soln2 eqns = [Eq(lhs, rhs)] for n in range(1, order): lhs = lhs.diff(var) rhs = rhs.diff(var) eq = Eq(lhs, rhs) eqns.append(eq) # BooleanTrue/False awkwardly show up for trivial equations if any(isinstance(eq, BooleanFalse) for eq in eqns): return False eqns = [eq for eq in eqns if not isinstance(eq, BooleanTrue)] try: constant_solns = solve(eqns, constants2) except NotImplementedError: return False # Sometimes returns a dict and sometimes a list of dicts if isinstance(constant_solns, dict): constant_solns = [constant_solns] # after solving the issue 17418, maybe we don't need the following checksol code. for constant_soln in constant_solns: for eq in eqns: eq=eq.rhs-eq.lhs if checksol(eq, constant_soln) is not True: return False # If any solution gives all constants as expressions that don't depend on # x then there exists constants for soln2 that give soln1 for constant_soln in constant_solns: if not any(c.has(var) for c in constant_soln.values()): return True return False def _nth_linear_match(eq, func, order): r""" Matches a differential equation to the linear form: .. math:: a_n(x) y^{(n)} + \cdots + a_1(x)y' + a_0(x) y + B(x) = 0 Returns a dict of order:coeff terms, where order is the order of the derivative on each term, and coeff is the coefficient of that derivative. The key ``-1`` holds the function `B(x)`. Returns ``None`` if the ODE is not linear. This function assumes that ``func`` has already been checked to be good. Examples ======== >>> from sympy import Function, cos, sin >>> from sympy.abc import x >>> from sympy.solvers.ode.ode import _nth_linear_match >>> f = Function('f') >>> _nth_linear_match(f(x).diff(x, 3) + 2*f(x).diff(x) + ... x*f(x).diff(x, 2) + cos(x)*f(x).diff(x) + x - f(x) - ... sin(x), f(x), 3) {-1: x - sin(x), 0: -1, 1: cos(x) + 2, 2: x, 3: 1} >>> _nth_linear_match(f(x).diff(x, 3) + 2*f(x).diff(x) + ... x*f(x).diff(x, 2) + cos(x)*f(x).diff(x) + x - f(x) - ... sin(f(x)), f(x), 3) == None True """ x = func.args[0] one_x = {x} terms = {i: S.Zero for i in range(-1, order + 1)} for i in Add.make_args(eq): if not i.has(func): terms[-1] += i else: c, f = i.as_independent(func) if (isinstance(f, Derivative) and set(f.variables) == one_x and f.args[0] == func): terms[f.derivative_count] += c elif f == func: terms[len(f.args[1:])] += c else: return None return terms def ode_nth_linear_euler_eq_homogeneous(eq, func, order, match, returns='sol'): r""" Solves an `n`\th order linear homogeneous variable-coefficient Cauchy-Euler equidimensional ordinary differential equation. This is an equation with form `0 = a_0 f(x) + a_1 x f'(x) + a_2 x^2 f''(x) \cdots`. These equations can be solved in a general manner, by substituting solutions of the form `f(x) = x^r`, and deriving a characteristic equation for `r`. When there are repeated roots, we include extra terms of the form `C_{r k} \ln^k(x) x^r`, where `C_{r k}` is an arbitrary integration constant, `r` is a root of the characteristic equation, and `k` ranges over the multiplicity of `r`. In the cases where the roots are complex, solutions of the form `C_1 x^a \sin(b \log(x)) + C_2 x^a \cos(b \log(x))` are returned, based on expansions with Euler's formula. The general solution is the sum of the terms found. If SymPy cannot find exact roots to the characteristic equation, a :py:obj:`~.ComplexRootOf` instance will be returned instead. >>> from sympy import Function, dsolve >>> from sympy.abc import x >>> f = Function('f') >>> dsolve(4*x**2*f(x).diff(x, 2) + f(x), f(x), ... hint='nth_linear_euler_eq_homogeneous') ... # doctest: +NORMALIZE_WHITESPACE Eq(f(x), sqrt(x)*(C1 + C2*log(x))) Note that because this method does not involve integration, there is no ``nth_linear_euler_eq_homogeneous_Integral`` hint. The following is for internal use: - ``returns = 'sol'`` returns the solution to the ODE. - ``returns = 'list'`` returns a list of linearly independent solutions, corresponding to the fundamental solution set, for use with non homogeneous solution methods like variation of parameters and undetermined coefficients. Note that, though the solutions should be linearly independent, this function does not explicitly check that. You can do ``assert simplify(wronskian(sollist)) != 0`` to check for linear independence. Also, ``assert len(sollist) == order`` will need to pass. - ``returns = 'both'``, return a dictionary ``{'sol': <solution to ODE>, 'list': <list of linearly independent solutions>}``. Examples ======== >>> from sympy import Function, dsolve, pprint >>> from sympy.abc import x >>> f = Function('f') >>> eq = f(x).diff(x, 2)*x**2 - 4*f(x).diff(x)*x + 6*f(x) >>> pprint(dsolve(eq, f(x), ... hint='nth_linear_euler_eq_homogeneous')) 2 f(x) = x *(C1 + C2*x) References ========== - https://en.wikipedia.org/wiki/Cauchy%E2%80%93Euler_equation - C. Bender & S. Orszag, "Advanced Mathematical Methods for Scientists and Engineers", Springer 1999, pp. 12 # indirect doctest """ # XXX: This global collectterms hack should be removed. global collectterms collectterms = [] x = func.args[0] f = func.func r = match # First, set up characteristic equation. chareq, symbol = S.Zero, Dummy('x') for i in r.keys(): if not isinstance(i, str) and i >= 0: chareq += (r[i]*diff(x**symbol, x, i)*x**-symbol).expand() chareq = Poly(chareq, symbol) chareqroots = [rootof(chareq, k) for k in range(chareq.degree())] # A generator of constants constants = list(get_numbered_constants(eq, num=chareq.degree()*2)) constants.reverse() # Create a dict root: multiplicity or charroots charroots = defaultdict(int) for root in chareqroots: charroots[root] += 1 gsol = S.Zero # We need keep track of terms so we can run collect() at the end. # This is necessary for constantsimp to work properly. ln = log for root, multiplicity in charroots.items(): for i in range(multiplicity): if isinstance(root, RootOf): gsol += (x**root) * constants.pop() if multiplicity != 1: raise ValueError("Value should be 1") collectterms = [(0, root, 0)] + collectterms elif root.is_real: gsol += ln(x)**i*(x**root) * constants.pop() collectterms = [(i, root, 0)] + collectterms else: reroot = re(root) imroot = im(root) gsol += ln(x)**i * (x**reroot) * ( constants.pop() * sin(abs(imroot)*ln(x)) + constants.pop() * cos(imroot*ln(x))) # Preserve ordering (multiplicity, real part, imaginary part) # It will be assumed implicitly when constructing # fundamental solution sets. collectterms = [(i, reroot, imroot)] + collectterms if returns == 'sol': return Eq(f(x), gsol) elif returns in ('list' 'both'): # HOW TO TEST THIS CODE? (dsolve does not pass 'returns' through) # Create a list of (hopefully) linearly independent solutions gensols = [] # Keep track of when to use sin or cos for nonzero imroot for i, reroot, imroot in collectterms: if imroot == 0: gensols.append(ln(x)**i*x**reroot) else: sin_form = ln(x)**i*x**reroot*sin(abs(imroot)*ln(x)) if sin_form in gensols: cos_form = ln(x)**i*x**reroot*cos(imroot*ln(x)) gensols.append(cos_form) else: gensols.append(sin_form) if returns == 'list': return gensols else: return {'sol': Eq(f(x), gsol), 'list': gensols} else: raise ValueError('Unknown value for key "returns".') def ode_nth_linear_euler_eq_nonhomogeneous_undetermined_coefficients(eq, func, order, match, returns='sol'): r""" Solves an `n`\th order linear non homogeneous Cauchy-Euler equidimensional ordinary differential equation using undetermined coefficients. This is an equation with form `g(x) = a_0 f(x) + a_1 x f'(x) + a_2 x^2 f''(x) \cdots`. These equations can be solved in a general manner, by substituting solutions of the form `x = exp(t)`, and deriving a characteristic equation of form `g(exp(t)) = b_0 f(t) + b_1 f'(t) + b_2 f''(t) \cdots` which can be then solved by nth_linear_constant_coeff_undetermined_coefficients if g(exp(t)) has finite number of linearly independent derivatives. Functions that fit this requirement are finite sums functions of the form `a x^i e^{b x} \sin(c x + d)` or `a x^i e^{b x} \cos(c x + d)`, where `i` is a non-negative integer and `a`, `b`, `c`, and `d` are constants. For example any polynomial in `x`, functions like `x^2 e^{2 x}`, `x \sin(x)`, and `e^x \cos(x)` can all be used. Products of `\sin`'s and `\cos`'s have a finite number of derivatives, because they can be expanded into `\sin(a x)` and `\cos(b x)` terms. However, SymPy currently cannot do that expansion, so you will need to manually rewrite the expression in terms of the above to use this method. So, for example, you will need to manually convert `\sin^2(x)` into `(1 + \cos(2 x))/2` to properly apply the method of undetermined coefficients on it. After replacement of x by exp(t), this method works by creating a trial function from the expression and all of its linear independent derivatives and substituting them into the original ODE. The coefficients for each term will be a system of linear equations, which are be solved for and substituted, giving the solution. If any of the trial functions are linearly dependent on the solution to the homogeneous equation, they are multiplied by sufficient `x` to make them linearly independent. Examples ======== >>> from sympy import dsolve, Function, Derivative, log >>> from sympy.abc import x >>> f = Function('f') >>> eq = x**2*Derivative(f(x), x, x) - 2*x*Derivative(f(x), x) + 2*f(x) - log(x) >>> dsolve(eq, f(x), ... hint='nth_linear_euler_eq_nonhomogeneous_undetermined_coefficients').expand() Eq(f(x), C1*x + C2*x**2 + log(x)/2 + 3/4) """ x = func.args[0] f = func.func r = match chareq, eq, symbol = S.Zero, S.Zero, Dummy('x') for i in r.keys(): if not isinstance(i, str) and i >= 0: chareq += (r[i]*diff(x**symbol, x, i)*x**-symbol).expand() for i in range(1,degree(Poly(chareq, symbol))+1): eq += chareq.coeff(symbol**i)*diff(f(x), x, i) if chareq.as_coeff_add(symbol)[0]: eq += chareq.as_coeff_add(symbol)[0]*f(x) e, re = posify(r[-1].subs(x, exp(x))) eq += e.subs(re) match = _nth_linear_match(eq, f(x), ode_order(eq, f(x))) eq_homogeneous = Add(eq,-match[-1]) match['trialset'] = _undetermined_coefficients_match(match[-1], x, func, eq_homogeneous)['trialset'] return ode_nth_linear_constant_coeff_undetermined_coefficients(eq, func, order, match).subs(x, log(x)).subs(f(log(x)), f(x)).expand() def ode_nth_linear_euler_eq_nonhomogeneous_variation_of_parameters(eq, func, order, match, returns='sol'): r""" Solves an `n`\th order linear non homogeneous Cauchy-Euler equidimensional ordinary differential equation using variation of parameters. This is an equation with form `g(x) = a_0 f(x) + a_1 x f'(x) + a_2 x^2 f''(x) \cdots`. This method works by assuming that the particular solution takes the form .. math:: \sum_{x=1}^{n} c_i(x) y_i(x) {a_n} {x^n} \text{,} where `y_i` is the `i`\th solution to the homogeneous equation. The solution is then solved using Wronskian's and Cramer's Rule. The particular solution is given by multiplying eq given below with `a_n x^{n}` .. math:: \sum_{x=1}^n \left( \int \frac{W_i(x)}{W(x)} \,dx \right) y_i(x) \text{,} where `W(x)` is the Wronskian of the fundamental system (the system of `n` linearly independent solutions to the homogeneous equation), and `W_i(x)` is the Wronskian of the fundamental system with the `i`\th column replaced with `[0, 0, \cdots, 0, \frac{x^{- n}}{a_n} g{\left(x \right)}]`. This method is general enough to solve any `n`\th order inhomogeneous linear differential equation, but sometimes SymPy cannot simplify the Wronskian well enough to integrate it. If this method hangs, try using the ``nth_linear_constant_coeff_variation_of_parameters_Integral`` hint and simplifying the integrals manually. Also, prefer using ``nth_linear_constant_coeff_undetermined_coefficients`` when it applies, because it doesn't use integration, making it faster and more reliable. Warning, using simplify=False with 'nth_linear_constant_coeff_variation_of_parameters' in :py:meth:`~sympy.solvers.ode.dsolve` may cause it to hang, because it will not attempt to simplify the Wronskian before integrating. It is recommended that you only use simplify=False with 'nth_linear_constant_coeff_variation_of_parameters_Integral' for this method, especially if the solution to the homogeneous equation has trigonometric functions in it. Examples ======== >>> from sympy import Function, dsolve, Derivative >>> from sympy.abc import x >>> f = Function('f') >>> eq = x**2*Derivative(f(x), x, x) - 2*x*Derivative(f(x), x) + 2*f(x) - x**4 >>> dsolve(eq, f(x), ... hint='nth_linear_euler_eq_nonhomogeneous_variation_of_parameters').expand() Eq(f(x), C1*x + C2*x**2 + x**4/6) """ x = func.args[0] f = func.func r = match gensol = ode_nth_linear_euler_eq_homogeneous(eq, func, order, match, returns='both') match.update(gensol) r[-1] = r[-1]/r[ode_order(eq, f(x))] sol = _solve_variation_of_parameters(eq, func, order, match) return Eq(f(x), r['sol'].rhs + (sol.rhs - r['sol'].rhs)*r[ode_order(eq, f(x))]) def ode_1st_power_series(eq, func, order, match): r""" The power series solution is a method which gives the Taylor series expansion to the solution of a differential equation. For a first order differential equation `\frac{dy}{dx} = h(x, y)`, a power series solution exists at a point `x = x_{0}` if `h(x, y)` is analytic at `x_{0}`. The solution is given by .. math:: y(x) = y(x_{0}) + \sum_{n = 1}^{\infty} \frac{F_{n}(x_{0},b)(x - x_{0})^n}{n!}, where `y(x_{0}) = b` is the value of y at the initial value of `x_{0}`. To compute the values of the `F_{n}(x_{0},b)` the following algorithm is followed, until the required number of terms are generated. 1. `F_1 = h(x_{0}, b)` 2. `F_{n+1} = \frac{\partial F_{n}}{\partial x} + \frac{\partial F_{n}}{\partial y}F_{1}` Examples ======== >>> from sympy import Function, pprint, exp >>> from sympy.solvers.ode.ode import dsolve >>> from sympy.abc import x >>> f = Function('f') >>> eq = exp(x)*(f(x).diff(x)) - f(x) >>> pprint(dsolve(eq, hint='1st_power_series')) 3 4 5 C1*x C1*x C1*x / 6\ f(x) = C1 + C1*x - ----- + ----- + ----- + O\x / 6 24 60 References ========== - Travis W. Walker, Analytic power series technique for solving first-order differential equations, p.p 17, 18 """ x = func.args[0] y = match['y'] f = func.func h = -match[match['d']]/match[match['e']] point = match.get('f0') value = match.get('f0val') terms = match.get('terms') # First term F = h if not h: return Eq(f(x), value) # Initialization series = value if terms > 1: hc = h.subs({x: point, y: value}) if hc.has(oo) or hc.has(NaN) or hc.has(zoo): # Derivative does not exist, not analytic return Eq(f(x), oo) elif hc: series += hc*(x - point) for factcount in range(2, terms): Fnew = F.diff(x) + F.diff(y)*h Fnewc = Fnew.subs({x: point, y: value}) # Same logic as above if Fnewc.has(oo) or Fnewc.has(NaN) or Fnewc.has(-oo) or Fnewc.has(zoo): return Eq(f(x), oo) series += Fnewc*((x - point)**factcount)/factorial(factcount) F = Fnew series += Order(x**terms) return Eq(f(x), series) def ode_nth_linear_constant_coeff_homogeneous(eq, func, order, match, returns='sol'): r""" Solves an `n`\th order linear homogeneous differential equation with constant coefficients. This is an equation of the form .. math:: a_n f^{(n)}(x) + a_{n-1} f^{(n-1)}(x) + \cdots + a_1 f'(x) + a_0 f(x) = 0\text{.} These equations can be solved in a general manner, by taking the roots of the characteristic equation `a_n m^n + a_{n-1} m^{n-1} + \cdots + a_1 m + a_0 = 0`. The solution will then be the sum of `C_n x^i e^{r x}` terms, for each where `C_n` is an arbitrary constant, `r` is a root of the characteristic equation and `i` is one of each from 0 to the multiplicity of the root - 1 (for example, a root 3 of multiplicity 2 would create the terms `C_1 e^{3 x} + C_2 x e^{3 x}`). The exponential is usually expanded for complex roots using Euler's equation `e^{I x} = \cos(x) + I \sin(x)`. Complex roots always come in conjugate pairs in polynomials with real coefficients, so the two roots will be represented (after simplifying the constants) as `e^{a x} \left(C_1 \cos(b x) + C_2 \sin(b x)\right)`. If SymPy cannot find exact roots to the characteristic equation, a :py:class:`~sympy.polys.rootoftools.ComplexRootOf` instance will be return instead. >>> from sympy import Function, dsolve >>> from sympy.abc import x >>> f = Function('f') >>> dsolve(f(x).diff(x, 5) + 10*f(x).diff(x) - 2*f(x), f(x), ... hint='nth_linear_constant_coeff_homogeneous') ... # doctest: +NORMALIZE_WHITESPACE Eq(f(x), C5*exp(x*CRootOf(_x**5 + 10*_x - 2, 0)) + (C1*sin(x*im(CRootOf(_x**5 + 10*_x - 2, 1))) + C2*cos(x*im(CRootOf(_x**5 + 10*_x - 2, 1))))*exp(x*re(CRootOf(_x**5 + 10*_x - 2, 1))) + (C3*sin(x*im(CRootOf(_x**5 + 10*_x - 2, 3))) + C4*cos(x*im(CRootOf(_x**5 + 10*_x - 2, 3))))*exp(x*re(CRootOf(_x**5 + 10*_x - 2, 3)))) Note that because this method does not involve integration, there is no ``nth_linear_constant_coeff_homogeneous_Integral`` hint. The following is for internal use: - ``returns = 'sol'`` returns the solution to the ODE. - ``returns = 'list'`` returns a list of linearly independent solutions, for use with non homogeneous solution methods like variation of parameters and undetermined coefficients. Note that, though the solutions should be linearly independent, this function does not explicitly check that. You can do ``assert simplify(wronskian(sollist)) != 0`` to check for linear independence. Also, ``assert len(sollist) == order`` will need to pass. - ``returns = 'both'``, return a dictionary ``{'sol': <solution to ODE>, 'list': <list of linearly independent solutions>}``. Examples ======== >>> from sympy import Function, dsolve, pprint >>> from sympy.abc import x >>> f = Function('f') >>> pprint(dsolve(f(x).diff(x, 4) + 2*f(x).diff(x, 3) - ... 2*f(x).diff(x, 2) - 6*f(x).diff(x) + 5*f(x), f(x), ... hint='nth_linear_constant_coeff_homogeneous')) x -2*x f(x) = (C1 + C2*x)*e + (C3*sin(x) + C4*cos(x))*e References ========== - https://en.wikipedia.org/wiki/Linear_differential_equation section: Nonhomogeneous_equation_with_constant_coefficients - M. Tenenbaum & H. Pollard, "Ordinary Differential Equations", Dover 1963, pp. 211 # indirect doctest """ x = func.args[0] f = func.func r = match # First, set up characteristic equation. chareq, symbol = S.Zero, Dummy('x') for i in r.keys(): if type(i) == str or i < 0: pass else: chareq += r[i]*symbol**i chareq = Poly(chareq, symbol) # Can't just call roots because it doesn't return rootof for unsolveable # polynomials. chareqroots = roots(chareq, multiple=True) if len(chareqroots) != order: chareqroots = [rootof(chareq, k) for k in range(chareq.degree())] chareq_is_complex = not all([i.is_real for i in chareq.all_coeffs()]) # A generator of constants constants = list(get_numbered_constants(eq, num=chareq.degree()*2)) # Create a dict root: multiplicity or charroots charroots = defaultdict(int) for root in chareqroots: charroots[root] += 1 # We need to keep track of terms so we can run collect() at the end. # This is necessary for constantsimp to work properly. # # XXX: This global collectterms hack should be removed. global collectterms collectterms = [] gensols = [] conjugate_roots = [] # used to prevent double-use of conjugate roots # Loop over roots in theorder provided by roots/rootof... for root in chareqroots: # but don't repoeat multiple roots. if root not in charroots: continue multiplicity = charroots.pop(root) for i in range(multiplicity): if chareq_is_complex: gensols.append(x**i*exp(root*x)) collectterms = [(i, root, 0)] + collectterms continue reroot = re(root) imroot = im(root) if imroot.has(atan2) and reroot.has(atan2): # Remove this condition when re and im stop returning # circular atan2 usages. gensols.append(x**i*exp(root*x)) collectterms = [(i, root, 0)] + collectterms else: if root in conjugate_roots: collectterms = [(i, reroot, imroot)] + collectterms continue if imroot == 0: gensols.append(x**i*exp(reroot*x)) collectterms = [(i, reroot, 0)] + collectterms continue conjugate_roots.append(conjugate(root)) gensols.append(x**i*exp(reroot*x) * sin(abs(imroot) * x)) gensols.append(x**i*exp(reroot*x) * cos( imroot * x)) # This ordering is important collectterms = [(i, reroot, imroot)] + collectterms if returns == 'list': return gensols elif returns in ('sol' 'both'): gsol = Add(*[i*j for (i, j) in zip(constants, gensols)]) if returns == 'sol': return Eq(f(x), gsol) else: return {'sol': Eq(f(x), gsol), 'list': gensols} else: raise ValueError('Unknown value for key "returns".') def ode_nth_linear_constant_coeff_undetermined_coefficients(eq, func, order, match): r""" Solves an `n`\th order linear differential equation with constant coefficients using the method of undetermined coefficients. This method works on differential equations of the form .. math:: a_n f^{(n)}(x) + a_{n-1} f^{(n-1)}(x) + \cdots + a_1 f'(x) + a_0 f(x) = P(x)\text{,} where `P(x)` is a function that has a finite number of linearly independent derivatives. Functions that fit this requirement are finite sums functions of the form `a x^i e^{b x} \sin(c x + d)` or `a x^i e^{b x} \cos(c x + d)`, where `i` is a non-negative integer and `a`, `b`, `c`, and `d` are constants. For example any polynomial in `x`, functions like `x^2 e^{2 x}`, `x \sin(x)`, and `e^x \cos(x)` can all be used. Products of `\sin`'s and `\cos`'s have a finite number of derivatives, because they can be expanded into `\sin(a x)` and `\cos(b x)` terms. However, SymPy currently cannot do that expansion, so you will need to manually rewrite the expression in terms of the above to use this method. So, for example, you will need to manually convert `\sin^2(x)` into `(1 + \cos(2 x))/2` to properly apply the method of undetermined coefficients on it. This method works by creating a trial function from the expression and all of its linear independent derivatives and substituting them into the original ODE. The coefficients for each term will be a system of linear equations, which are be solved for and substituted, giving the solution. If any of the trial functions are linearly dependent on the solution to the homogeneous equation, they are multiplied by sufficient `x` to make them linearly independent. Examples ======== >>> from sympy import Function, dsolve, pprint, exp, cos >>> from sympy.abc import x >>> f = Function('f') >>> pprint(dsolve(f(x).diff(x, 2) + 2*f(x).diff(x) + f(x) - ... 4*exp(-x)*x**2 + cos(2*x), f(x), ... hint='nth_linear_constant_coeff_undetermined_coefficients')) / / 3\\ | | x || -x 4*sin(2*x) 3*cos(2*x) f(x) = |C1 + x*|C2 + --||*e - ---------- + ---------- \ \ 3 // 25 25 References ========== - https://en.wikipedia.org/wiki/Method_of_undetermined_coefficients - M. Tenenbaum & H. Pollard, "Ordinary Differential Equations", Dover 1963, pp. 221 # indirect doctest """ gensol = ode_nth_linear_constant_coeff_homogeneous(eq, func, order, match, returns='both') match.update(gensol) return _solve_undetermined_coefficients(eq, func, order, match) def _solve_undetermined_coefficients(eq, func, order, match): r""" Helper function for the method of undetermined coefficients. See the :py:meth:`~sympy.solvers.ode.ode.ode_nth_linear_constant_coeff_undetermined_coefficients` docstring for more information on this method. The parameter ``match`` should be a dictionary that has the following keys: ``list`` A list of solutions to the homogeneous equation, such as the list returned by ``ode_nth_linear_constant_coeff_homogeneous(returns='list')``. ``sol`` The general solution, such as the solution returned by ``ode_nth_linear_constant_coeff_homogeneous(returns='sol')``. ``trialset`` The set of trial functions as returned by ``_undetermined_coefficients_match()['trialset']``. """ x = func.args[0] f = func.func r = match coeffs = numbered_symbols('a', cls=Dummy) coefflist = [] gensols = r['list'] gsol = r['sol'] trialset = r['trialset'] if len(gensols) != order: raise NotImplementedError("Cannot find " + str(order) + " solutions to the homogeneous equation necessary to apply" + " undetermined coefficients to " + str(eq) + " (number of terms != order)") trialfunc = 0 for i in trialset: c = next(coeffs) coefflist.append(c) trialfunc += c*i eqs = sub_func_doit(eq, f(x), trialfunc) coeffsdict = dict(list(zip(trialset, [0]*(len(trialset) + 1)))) eqs = _mexpand(eqs) for i in Add.make_args(eqs): s = separatevars(i, dict=True, symbols=[x]) if coeffsdict.get(s[x]): coeffsdict[s[x]] += s['coeff'] else: coeffsdict[s[x]] = s['coeff'] coeffvals = solve(list(coeffsdict.values()), coefflist) if not coeffvals: raise NotImplementedError( "Could not solve `%s` using the " "method of undetermined coefficients " "(unable to solve for coefficients)." % eq) psol = trialfunc.subs(coeffvals) return Eq(f(x), gsol.rhs + psol) def _undetermined_coefficients_match(expr, x, func=None, eq_homogeneous=S.Zero): r""" Returns a trial function match if undetermined coefficients can be applied to ``expr``, and ``None`` otherwise. A trial expression can be found for an expression for use with the method of undetermined coefficients if the expression is an additive/multiplicative combination of constants, polynomials in `x` (the independent variable of expr), `\sin(a x + b)`, `\cos(a x + b)`, and `e^{a x}` terms (in other words, it has a finite number of linearly independent derivatives). Note that you may still need to multiply each term returned here by sufficient `x` to make it linearly independent with the solutions to the homogeneous equation. This is intended for internal use by ``undetermined_coefficients`` hints. SymPy currently has no way to convert `\sin^n(x) \cos^m(y)` into a sum of only `\sin(a x)` and `\cos(b x)` terms, so these are not implemented. So, for example, you will need to manually convert `\sin^2(x)` into `[1 + \cos(2 x)]/2` to properly apply the method of undetermined coefficients on it. Examples ======== >>> from sympy import log, exp >>> from sympy.solvers.ode.ode import _undetermined_coefficients_match >>> from sympy.abc import x >>> _undetermined_coefficients_match(9*x*exp(x) + exp(-x), x) {'test': True, 'trialset': {x*exp(x), exp(-x), exp(x)}} >>> _undetermined_coefficients_match(log(x), x) {'test': False} """ a = Wild('a', exclude=[x]) b = Wild('b', exclude=[x]) expr = powsimp(expr, combine='exp') # exp(x)*exp(2*x + 1) => exp(3*x + 1) retdict = {} def _test_term(expr, x): r""" Test if ``expr`` fits the proper form for undetermined coefficients. """ if not expr.has(x): return True elif expr.is_Add: return all(_test_term(i, x) for i in expr.args) elif expr.is_Mul: if expr.has(sin, cos): foundtrig = False # Make sure that there is only one trig function in the args. # See the docstring. for i in expr.args: if i.has(sin, cos): if foundtrig: return False else: foundtrig = True return all(_test_term(i, x) for i in expr.args) elif expr.is_Function: if expr.func in (sin, cos, exp, sinh, cosh): if expr.args[0].match(a*x + b): return True else: return False else: return False elif expr.is_Pow and expr.base.is_Symbol and expr.exp.is_Integer and \ expr.exp >= 0: return True elif expr.is_Pow and expr.base.is_number: if expr.exp.match(a*x + b): return True else: return False elif expr.is_Symbol or expr.is_number: return True else: return False def _get_trial_set(expr, x, exprs=set()): r""" Returns a set of trial terms for undetermined coefficients. The idea behind undetermined coefficients is that the terms expression repeat themselves after a finite number of derivatives, except for the coefficients (they are linearly dependent). So if we collect these, we should have the terms of our trial function. """ def _remove_coefficient(expr, x): r""" Returns the expression without a coefficient. Similar to expr.as_independent(x)[1], except it only works multiplicatively. """ term = S.One if expr.is_Mul: for i in expr.args: if i.has(x): term *= i elif expr.has(x): term = expr return term expr = expand_mul(expr) if expr.is_Add: for term in expr.args: if _remove_coefficient(term, x) in exprs: pass else: exprs.add(_remove_coefficient(term, x)) exprs = exprs.union(_get_trial_set(term, x, exprs)) else: term = _remove_coefficient(expr, x) tmpset = exprs.union({term}) oldset = set() while tmpset != oldset: # If you get stuck in this loop, then _test_term is probably # broken oldset = tmpset.copy() expr = expr.diff(x) term = _remove_coefficient(expr, x) if term.is_Add: tmpset = tmpset.union(_get_trial_set(term, x, tmpset)) else: tmpset.add(term) exprs = tmpset return exprs def is_homogeneous_solution(term): r""" This function checks whether the given trialset contains any root of homogenous equation""" return expand(sub_func_doit(eq_homogeneous, func, term)).is_zero retdict['test'] = _test_term(expr, x) if retdict['test']: # Try to generate a list of trial solutions that will have the # undetermined coefficients. Note that if any of these are not linearly # independent with any of the solutions to the homogeneous equation, # then they will need to be multiplied by sufficient x to make them so. # This function DOES NOT do that (it doesn't even look at the # homogeneous equation). temp_set = set() for i in Add.make_args(expr): act = _get_trial_set(i,x) if eq_homogeneous is not S.Zero: while any(is_homogeneous_solution(ts) for ts in act): act = {x*ts for ts in act} temp_set = temp_set.union(act) retdict['trialset'] = temp_set return retdict def ode_nth_linear_constant_coeff_variation_of_parameters(eq, func, order, match): r""" Solves an `n`\th order linear differential equation with constant coefficients using the method of variation of parameters. This method works on any differential equations of the form .. math:: f^{(n)}(x) + a_{n-1} f^{(n-1)}(x) + \cdots + a_1 f'(x) + a_0 f(x) = P(x)\text{.} This method works by assuming that the particular solution takes the form .. math:: \sum_{x=1}^{n} c_i(x) y_i(x)\text{,} where `y_i` is the `i`\th solution to the homogeneous equation. The solution is then solved using Wronskian's and Cramer's Rule. The particular solution is given by .. math:: \sum_{x=1}^n \left( \int \frac{W_i(x)}{W(x)} \,dx \right) y_i(x) \text{,} where `W(x)` is the Wronskian of the fundamental system (the system of `n` linearly independent solutions to the homogeneous equation), and `W_i(x)` is the Wronskian of the fundamental system with the `i`\th column replaced with `[0, 0, \cdots, 0, P(x)]`. This method is general enough to solve any `n`\th order inhomogeneous linear differential equation with constant coefficients, but sometimes SymPy cannot simplify the Wronskian well enough to integrate it. If this method hangs, try using the ``nth_linear_constant_coeff_variation_of_parameters_Integral`` hint and simplifying the integrals manually. Also, prefer using ``nth_linear_constant_coeff_undetermined_coefficients`` when it applies, because it doesn't use integration, making it faster and more reliable. Warning, using simplify=False with 'nth_linear_constant_coeff_variation_of_parameters' in :py:meth:`~sympy.solvers.ode.dsolve` may cause it to hang, because it will not attempt to simplify the Wronskian before integrating. It is recommended that you only use simplify=False with 'nth_linear_constant_coeff_variation_of_parameters_Integral' for this method, especially if the solution to the homogeneous equation has trigonometric functions in it. Examples ======== >>> from sympy import Function, dsolve, pprint, exp, log >>> from sympy.abc import x >>> f = Function('f') >>> pprint(dsolve(f(x).diff(x, 3) - 3*f(x).diff(x, 2) + ... 3*f(x).diff(x) - f(x) - exp(x)*log(x), f(x), ... hint='nth_linear_constant_coeff_variation_of_parameters')) / / / x*log(x) 11*x\\\ x f(x) = |C1 + x*|C2 + x*|C3 + -------- - ----|||*e \ \ \ 6 36 /// References ========== - https://en.wikipedia.org/wiki/Variation_of_parameters - http://planetmath.org/VariationOfParameters - M. Tenenbaum & H. Pollard, "Ordinary Differential Equations", Dover 1963, pp. 233 # indirect doctest """ gensol = ode_nth_linear_constant_coeff_homogeneous(eq, func, order, match, returns='both') match.update(gensol) return _solve_variation_of_parameters(eq, func, order, match) def _solve_variation_of_parameters(eq, func, order, match): r""" Helper function for the method of variation of parameters and nonhomogeneous euler eq. See the :py:meth:`~sympy.solvers.ode.ode.ode_nth_linear_constant_coeff_variation_of_parameters` docstring for more information on this method. The parameter ``match`` should be a dictionary that has the following keys: ``list`` A list of solutions to the homogeneous equation, such as the list returned by ``ode_nth_linear_constant_coeff_homogeneous(returns='list')``. ``sol`` The general solution, such as the solution returned by ``ode_nth_linear_constant_coeff_homogeneous(returns='sol')``. """ x = func.args[0] f = func.func r = match psol = 0 gensols = r['list'] gsol = r['sol'] wr = wronskian(gensols, x) if r.get('simplify', True): wr = simplify(wr) # We need much better simplification for # some ODEs. See issue 4662, for example. # To reduce commonly occurring sin(x)**2 + cos(x)**2 to 1 wr = trigsimp(wr, deep=True, recursive=True) if not wr: # The wronskian will be 0 iff the solutions are not linearly # independent. raise NotImplementedError("Cannot find " + str(order) + " solutions to the homogeneous equation necessary to apply " + "variation of parameters to " + str(eq) + " (Wronskian == 0)") if len(gensols) != order: raise NotImplementedError("Cannot find " + str(order) + " solutions to the homogeneous equation necessary to apply " + "variation of parameters to " + str(eq) + " (number of terms != order)") negoneterm = (-1)**(order) for i in gensols: psol += negoneterm*Integral(wronskian([sol for sol in gensols if sol != i], x)*r[-1]/wr, x)*i/r[order] negoneterm *= -1 if r.get('simplify', True): psol = simplify(psol) psol = trigsimp(psol, deep=True) return Eq(f(x), gsol.rhs + psol) def checkinfsol(eq, infinitesimals, func=None, order=None): r""" This function is used to check if the given infinitesimals are the actual infinitesimals of the given first order differential equation. This method is specific to the Lie Group Solver of ODEs. As of now, it simply checks, by substituting the infinitesimals in the partial differential equation. .. math:: \frac{\partial \eta}{\partial x} + \left(\frac{\partial \eta}{\partial y} - \frac{\partial \xi}{\partial x}\right)*h - \frac{\partial \xi}{\partial y}*h^{2} - \xi\frac{\partial h}{\partial x} - \eta\frac{\partial h}{\partial y} = 0 where `\eta`, and `\xi` are the infinitesimals and `h(x,y) = \frac{dy}{dx}` The infinitesimals should be given in the form of a list of dicts ``[{xi(x, y): inf, eta(x, y): inf}]``, corresponding to the output of the function infinitesimals. It returns a list of values of the form ``[(True/False, sol)]`` where ``sol`` is the value obtained after substituting the infinitesimals in the PDE. If it is ``True``, then ``sol`` would be 0. """ if isinstance(eq, Equality): eq = eq.lhs - eq.rhs if not func: eq, func = _preprocess(eq) variables = func.args if len(variables) != 1: raise ValueError("ODE's have only one independent variable") else: x = variables[0] if not order: order = ode_order(eq, func) if order != 1: raise NotImplementedError("Lie groups solver has been implemented " "only for first order differential equations") else: df = func.diff(x) a = Wild('a', exclude = [df]) b = Wild('b', exclude = [df]) match = collect(expand(eq), df).match(a*df + b) if match: h = -simplify(match[b]/match[a]) else: try: sol = solve(eq, df) except NotImplementedError: raise NotImplementedError("Infinitesimals for the " "first order ODE could not be found") else: h = sol[0] # Find infinitesimals for one solution y = Dummy('y') h = h.subs(func, y) xi = Function('xi')(x, y) eta = Function('eta')(x, y) dxi = Function('xi')(x, func) deta = Function('eta')(x, func) pde = (eta.diff(x) + (eta.diff(y) - xi.diff(x))*h - (xi.diff(y))*h**2 - xi*(h.diff(x)) - eta*(h.diff(y))) soltup = [] for sol in infinitesimals: tsol = {xi: S(sol[dxi]).subs(func, y), eta: S(sol[deta]).subs(func, y)} sol = simplify(pde.subs(tsol).doit()) if sol: soltup.append((False, sol.subs(y, func))) else: soltup.append((True, 0)) return soltup def _ode_lie_group_try_heuristic(eq, heuristic, func, match, inf): xi = Function("xi") eta = Function("eta") f = func.func x = func.args[0] y = match['y'] h = match['h'] tempsol = [] if not inf: try: inf = infinitesimals(eq, hint=heuristic, func=func, order=1, match=match) except ValueError: return None for infsim in inf: xiinf = (infsim[xi(x, func)]).subs(func, y) etainf = (infsim[eta(x, func)]).subs(func, y) # This condition creates recursion while using pdsolve. # Since the first step while solving a PDE of form # a*(f(x, y).diff(x)) + b*(f(x, y).diff(y)) + c = 0 # is to solve the ODE dy/dx = b/a if simplify(etainf/xiinf) == h: continue rpde = f(x, y).diff(x)*xiinf + f(x, y).diff(y)*etainf r = pdsolve(rpde, func=f(x, y)).rhs s = pdsolve(rpde - 1, func=f(x, y)).rhs newcoord = [_lie_group_remove(coord) for coord in [r, s]] r = Dummy("r") s = Dummy("s") C1 = Symbol("C1") rcoord = newcoord[0] scoord = newcoord[-1] try: sol = solve([r - rcoord, s - scoord], x, y, dict=True) if sol == []: continue except NotImplementedError: continue else: sol = sol[0] xsub = sol[x] ysub = sol[y] num = simplify(scoord.diff(x) + scoord.diff(y)*h) denom = simplify(rcoord.diff(x) + rcoord.diff(y)*h) if num and denom: diffeq = simplify((num/denom).subs([(x, xsub), (y, ysub)])) sep = separatevars(diffeq, symbols=[r, s], dict=True) if sep: # Trying to separate, r and s coordinates deq = integrate((1/sep[s]), s) + C1 - integrate(sep['coeff']*sep[r], r) # Substituting and reverting back to original coordinates deq = deq.subs([(r, rcoord), (s, scoord)]) try: sdeq = solve(deq, y) except NotImplementedError: tempsol.append(deq) else: return [Eq(f(x), sol) for sol in sdeq] elif denom: # (ds/dr) is zero which means s is constant return [Eq(f(x), solve(scoord - C1, y)[0])] elif num: # (dr/ds) is zero which means r is constant return [Eq(f(x), solve(rcoord - C1, y)[0])] # If nothing works, return solution as it is, without solving for y if tempsol: return [Eq(sol.subs(y, f(x)), 0) for sol in tempsol] return None def _ode_lie_group( s, func, order, match): heuristics = lie_heuristics inf = {} f = func.func x = func.args[0] df = func.diff(x) xi = Function("xi") eta = Function("eta") xis = match['xi'] etas = match['eta'] y = match.pop('y', None) if y: h = -simplify(match[match['d']]/match[match['e']]) y = y else: y = Dummy("y") h = s.subs(func, y) if xis is not None and etas is not None: inf = [{xi(x, f(x)): S(xis), eta(x, f(x)): S(etas)}] if checkinfsol(Eq(df, s), inf, func=f(x), order=1)[0][0]: heuristics = ["user_defined"] + list(heuristics) match = {'h': h, 'y': y} # This is done so that if any heuristic raises a ValueError # another heuristic can be used. sol = None for heuristic in heuristics: sol = _ode_lie_group_try_heuristic(Eq(df, s), heuristic, func, match, inf) if sol: return sol return sol def ode_lie_group(eq, func, order, match): r""" This hint implements the Lie group method of solving first order differential equations. The aim is to convert the given differential equation from the given coordinate system into another coordinate system where it becomes invariant under the one-parameter Lie group of translations. The converted ODE can be easily solved by quadrature. It makes use of the :py:meth:`sympy.solvers.ode.infinitesimals` function which returns the infinitesimals of the transformation. The coordinates `r` and `s` can be found by solving the following Partial Differential Equations. .. math :: \xi\frac{\partial r}{\partial x} + \eta\frac{\partial r}{\partial y} = 0 .. math :: \xi\frac{\partial s}{\partial x} + \eta\frac{\partial s}{\partial y} = 1 The differential equation becomes separable in the new coordinate system .. math :: \frac{ds}{dr} = \frac{\frac{\partial s}{\partial x} + h(x, y)\frac{\partial s}{\partial y}}{ \frac{\partial r}{\partial x} + h(x, y)\frac{\partial r}{\partial y}} After finding the solution by integration, it is then converted back to the original coordinate system by substituting `r` and `s` in terms of `x` and `y` again. Examples ======== >>> from sympy import Function, dsolve, exp, pprint >>> from sympy.abc import x >>> f = Function('f') >>> pprint(dsolve(f(x).diff(x) + 2*x*f(x) - x*exp(-x**2), f(x), ... hint='lie_group')) / 2\ 2 | x | -x f(x) = |C1 + --|*e \ 2 / References ========== - Solving differential equations by Symmetry Groups, John Starrett, pp. 1 - pp. 14 """ x = func.args[0] df = func.diff(x) try: eqsol = solve(eq, df) except NotImplementedError: eqsol = [] desols = [] for s in eqsol: sol = _ode_lie_group(s, func, order, match=match) if sol: desols.extend(sol) if desols == []: raise NotImplementedError("The given ODE " + str(eq) + " cannot be solved by" + " the lie group method") return desols def _lie_group_remove(coords): r""" This function is strictly meant for internal use by the Lie group ODE solving method. It replaces arbitrary functions returned by pdsolve as follows: 1] If coords is an arbitrary function, then its argument is returned. 2] An arbitrary function in an Add object is replaced by zero. 3] An arbitrary function in a Mul object is replaced by one. 4] If there is no arbitrary function coords is returned unchanged. Examples ======== >>> from sympy.solvers.ode.ode import _lie_group_remove >>> from sympy import Function >>> from sympy.abc import x, y >>> F = Function("F") >>> eq = x**2*y >>> _lie_group_remove(eq) x**2*y >>> eq = F(x**2*y) >>> _lie_group_remove(eq) x**2*y >>> eq = x*y**2 + F(x**3) >>> _lie_group_remove(eq) x*y**2 >>> eq = (F(x**3) + y)*x**4 >>> _lie_group_remove(eq) x**4*y """ if isinstance(coords, AppliedUndef): return coords.args[0] elif coords.is_Add: subfunc = coords.atoms(AppliedUndef) if subfunc: for func in subfunc: coords = coords.subs(func, 0) return coords elif coords.is_Pow: base, expr = coords.as_base_exp() base = _lie_group_remove(base) expr = _lie_group_remove(expr) return base**expr elif coords.is_Mul: mulargs = [] coordargs = coords.args for arg in coordargs: if not isinstance(coords, AppliedUndef): mulargs.append(_lie_group_remove(arg)) return Mul(*mulargs) return coords def infinitesimals(eq, func=None, order=None, hint='default', match=None): r""" The infinitesimal functions of an ordinary differential equation, `\xi(x,y)` and `\eta(x,y)`, are the infinitesimals of the Lie group of point transformations for which the differential equation is invariant. So, the ODE `y'=f(x,y)` would admit a Lie group `x^*=X(x,y;\varepsilon)=x+\varepsilon\xi(x,y)`, `y^*=Y(x,y;\varepsilon)=y+\varepsilon\eta(x,y)` such that `(y^*)'=f(x^*, y^*)`. A change of coordinates, to `r(x,y)` and `s(x,y)`, can be performed so this Lie group becomes the translation group, `r^*=r` and `s^*=s+\varepsilon`. They are tangents to the coordinate curves of the new system. Consider the transformation `(x, y) \to (X, Y)` such that the differential equation remains invariant. `\xi` and `\eta` are the tangents to the transformed coordinates `X` and `Y`, at `\varepsilon=0`. .. math:: \left(\frac{\partial X(x,y;\varepsilon)}{\partial\varepsilon }\right)|_{\varepsilon=0} = \xi, \left(\frac{\partial Y(x,y;\varepsilon)}{\partial\varepsilon }\right)|_{\varepsilon=0} = \eta, The infinitesimals can be found by solving the following PDE: >>> from sympy import Function, Eq, pprint >>> from sympy.abc import x, y >>> xi, eta, h = map(Function, ['xi', 'eta', 'h']) >>> h = h(x, y) # dy/dx = h >>> eta = eta(x, y) >>> xi = xi(x, y) >>> genform = Eq(eta.diff(x) + (eta.diff(y) - xi.diff(x))*h ... - (xi.diff(y))*h**2 - xi*(h.diff(x)) - eta*(h.diff(y)), 0) >>> pprint(genform) /d d \ d 2 d |--(eta(x, y)) - --(xi(x, y))|*h(x, y) - eta(x, y)*--(h(x, y)) - h (x, y)*--(x \dy dx / dy dy <BLANKLINE> d d i(x, y)) - xi(x, y)*--(h(x, y)) + --(eta(x, y)) = 0 dx dx Solving the above mentioned PDE is not trivial, and can be solved only by making intelligent assumptions for `\xi` and `\eta` (heuristics). Once an infinitesimal is found, the attempt to find more heuristics stops. This is done to optimise the speed of solving the differential equation. If a list of all the infinitesimals is needed, ``hint`` should be flagged as ``all``, which gives the complete list of infinitesimals. If the infinitesimals for a particular heuristic needs to be found, it can be passed as a flag to ``hint``. Examples ======== >>> from sympy import Function >>> from sympy.solvers.ode.ode import infinitesimals >>> from sympy.abc import x >>> f = Function('f') >>> eq = f(x).diff(x) - x**2*f(x) >>> infinitesimals(eq) [{eta(x, f(x)): exp(x**3/3), xi(x, f(x)): 0}] References ========== - Solving differential equations by Symmetry Groups, John Starrett, pp. 1 - pp. 14 """ if isinstance(eq, Equality): eq = eq.lhs - eq.rhs if not func: eq, func = _preprocess(eq) variables = func.args if len(variables) != 1: raise ValueError("ODE's have only one independent variable") else: x = variables[0] if not order: order = ode_order(eq, func) if order != 1: raise NotImplementedError("Infinitesimals for only " "first order ODE's have been implemented") else: df = func.diff(x) # Matching differential equation of the form a*df + b a = Wild('a', exclude = [df]) b = Wild('b', exclude = [df]) if match: # Used by lie_group hint h = match['h'] y = match['y'] else: match = collect(expand(eq), df).match(a*df + b) if match: h = -simplify(match[b]/match[a]) else: try: sol = solve(eq, df) except NotImplementedError: raise NotImplementedError("Infinitesimals for the " "first order ODE could not be found") else: h = sol[0] # Find infinitesimals for one solution y = Dummy("y") h = h.subs(func, y) u = Dummy("u") hx = h.diff(x) hy = h.diff(y) hinv = ((1/h).subs([(x, u), (y, x)])).subs(u, y) # Inverse ODE match = {'h': h, 'func': func, 'hx': hx, 'hy': hy, 'y': y, 'hinv': hinv} if hint == 'all': xieta = [] for heuristic in lie_heuristics: function = globals()['lie_heuristic_' + heuristic] inflist = function(match, comp=True) if inflist: xieta.extend([inf for inf in inflist if inf not in xieta]) if xieta: return xieta else: raise NotImplementedError("Infinitesimals could not be found for " "the given ODE") elif hint == 'default': for heuristic in lie_heuristics: function = globals()['lie_heuristic_' + heuristic] xieta = function(match, comp=False) if xieta: return xieta raise NotImplementedError("Infinitesimals could not be found for" " the given ODE") elif hint not in lie_heuristics: raise ValueError("Heuristic not recognized: " + hint) else: function = globals()['lie_heuristic_' + hint] xieta = function(match, comp=True) if xieta: return xieta else: raise ValueError("Infinitesimals could not be found using the" " given heuristic") def lie_heuristic_abaco1_simple(match, comp=False): r""" The first heuristic uses the following four sets of assumptions on `\xi` and `\eta` .. math:: \xi = 0, \eta = f(x) .. math:: \xi = 0, \eta = f(y) .. math:: \xi = f(x), \eta = 0 .. math:: \xi = f(y), \eta = 0 The success of this heuristic is determined by algebraic factorisation. For the first assumption `\xi = 0` and `\eta` to be a function of `x`, the PDE .. math:: \frac{\partial \eta}{\partial x} + (\frac{\partial \eta}{\partial y} - \frac{\partial \xi}{\partial x})*h - \frac{\partial \xi}{\partial y}*h^{2} - \xi*\frac{\partial h}{\partial x} - \eta*\frac{\partial h}{\partial y} = 0 reduces to `f'(x) - f\frac{\partial h}{\partial y} = 0` If `\frac{\partial h}{\partial y}` is a function of `x`, then this can usually be integrated easily. A similar idea is applied to the other 3 assumptions as well. References ========== - E.S Cheb-Terrab, L.G.S Duarte and L.A,C.P da Mota, Computer Algebra Solving of First Order ODEs Using Symmetry Methods, pp. 8 """ xieta = [] y = match['y'] h = match['h'] func = match['func'] x = func.args[0] hx = match['hx'] hy = match['hy'] xi = Function('xi')(x, func) eta = Function('eta')(x, func) hysym = hy.free_symbols if y not in hysym: try: fx = exp(integrate(hy, x)) except NotImplementedError: pass else: inf = {xi: S.Zero, eta: fx} if not comp: return [inf] if comp and inf not in xieta: xieta.append(inf) factor = hy/h facsym = factor.free_symbols if x not in facsym: try: fy = exp(integrate(factor, y)) except NotImplementedError: pass else: inf = {xi: S.Zero, eta: fy.subs(y, func)} if not comp: return [inf] if comp and inf not in xieta: xieta.append(inf) factor = -hx/h facsym = factor.free_symbols if y not in facsym: try: fx = exp(integrate(factor, x)) except NotImplementedError: pass else: inf = {xi: fx, eta: S.Zero} if not comp: return [inf] if comp and inf not in xieta: xieta.append(inf) factor = -hx/(h**2) facsym = factor.free_symbols if x not in facsym: try: fy = exp(integrate(factor, y)) except NotImplementedError: pass else: inf = {xi: fy.subs(y, func), eta: S.Zero} if not comp: return [inf] if comp and inf not in xieta: xieta.append(inf) if xieta: return xieta def lie_heuristic_abaco1_product(match, comp=False): r""" The second heuristic uses the following two assumptions on `\xi` and `\eta` .. math:: \eta = 0, \xi = f(x)*g(y) .. math:: \eta = f(x)*g(y), \xi = 0 The first assumption of this heuristic holds good if `\frac{1}{h^{2}}\frac{\partial^2}{\partial x \partial y}\log(h)` is separable in `x` and `y`, then the separated factors containing `x` is `f(x)`, and `g(y)` is obtained by .. math:: e^{\int f\frac{\partial}{\partial x}\left(\frac{1}{f*h}\right)\,dy} provided `f\frac{\partial}{\partial x}\left(\frac{1}{f*h}\right)` is a function of `y` only. The second assumption holds good if `\frac{dy}{dx} = h(x, y)` is rewritten as `\frac{dy}{dx} = \frac{1}{h(y, x)}` and the same properties of the first assumption satisfies. After obtaining `f(x)` and `g(y)`, the coordinates are again interchanged, to get `\eta` as `f(x)*g(y)` References ========== - E.S. Cheb-Terrab, A.D. Roche, Symmetries and First Order ODE Patterns, pp. 7 - pp. 8 """ xieta = [] y = match['y'] h = match['h'] hinv = match['hinv'] func = match['func'] x = func.args[0] xi = Function('xi')(x, func) eta = Function('eta')(x, func) inf = separatevars(((log(h).diff(y)).diff(x))/h**2, dict=True, symbols=[x, y]) if inf and inf['coeff']: fx = inf[x] gy = simplify(fx*((1/(fx*h)).diff(x))) gysyms = gy.free_symbols if x not in gysyms: gy = exp(integrate(gy, y)) inf = {eta: S.Zero, xi: (fx*gy).subs(y, func)} if not comp: return [inf] if comp and inf not in xieta: xieta.append(inf) u1 = Dummy("u1") inf = separatevars(((log(hinv).diff(y)).diff(x))/hinv**2, dict=True, symbols=[x, y]) if inf and inf['coeff']: fx = inf[x] gy = simplify(fx*((1/(fx*hinv)).diff(x))) gysyms = gy.free_symbols if x not in gysyms: gy = exp(integrate(gy, y)) etaval = fx*gy etaval = (etaval.subs([(x, u1), (y, x)])).subs(u1, y) inf = {eta: etaval.subs(y, func), xi: S.Zero} if not comp: return [inf] if comp and inf not in xieta: xieta.append(inf) if xieta: return xieta def lie_heuristic_bivariate(match, comp=False): r""" The third heuristic assumes the infinitesimals `\xi` and `\eta` to be bi-variate polynomials in `x` and `y`. The assumption made here for the logic below is that `h` is a rational function in `x` and `y` though that may not be necessary for the infinitesimals to be bivariate polynomials. The coefficients of the infinitesimals are found out by substituting them in the PDE and grouping similar terms that are polynomials and since they form a linear system, solve and check for non trivial solutions. The degree of the assumed bivariates are increased till a certain maximum value. References ========== - Lie Groups and Differential Equations pp. 327 - pp. 329 """ h = match['h'] hx = match['hx'] hy = match['hy'] func = match['func'] x = func.args[0] y = match['y'] xi = Function('xi')(x, func) eta = Function('eta')(x, func) if h.is_rational_function(): # The maximum degree that the infinitesimals can take is # calculated by this technique. etax, etay, etad, xix, xiy, xid = symbols("etax etay etad xix xiy xid") ipde = etax + (etay - xix)*h - xiy*h**2 - xid*hx - etad*hy num, denom = cancel(ipde).as_numer_denom() deg = Poly(num, x, y).total_degree() deta = Function('deta')(x, y) dxi = Function('dxi')(x, y) ipde = (deta.diff(x) + (deta.diff(y) - dxi.diff(x))*h - (dxi.diff(y))*h**2 - dxi*hx - deta*hy) xieq = Symbol("xi0") etaeq = Symbol("eta0") for i in range(deg + 1): if i: xieq += Add(*[ Symbol("xi_" + str(power) + "_" + str(i - power))*x**power*y**(i - power) for power in range(i + 1)]) etaeq += Add(*[ Symbol("eta_" + str(power) + "_" + str(i - power))*x**power*y**(i - power) for power in range(i + 1)]) pden, denom = (ipde.subs({dxi: xieq, deta: etaeq}).doit()).as_numer_denom() pden = expand(pden) # If the individual terms are monomials, the coefficients # are grouped if pden.is_polynomial(x, y) and pden.is_Add: polyy = Poly(pden, x, y).as_dict() if polyy: symset = xieq.free_symbols.union(etaeq.free_symbols) - {x, y} soldict = solve(polyy.values(), *symset) if isinstance(soldict, list): soldict = soldict[0] if any(soldict.values()): xired = xieq.subs(soldict) etared = etaeq.subs(soldict) # Scaling is done by substituting one for the parameters # This can be any number except zero. dict_ = {sym: 1 for sym in symset} inf = {eta: etared.subs(dict_).subs(y, func), xi: xired.subs(dict_).subs(y, func)} return [inf] def lie_heuristic_chi(match, comp=False): r""" The aim of the fourth heuristic is to find the function `\chi(x, y)` that satisfies the PDE `\frac{d\chi}{dx} + h\frac{d\chi}{dx} - \frac{\partial h}{\partial y}\chi = 0`. This assumes `\chi` to be a bivariate polynomial in `x` and `y`. By intuition, `h` should be a rational function in `x` and `y`. The method used here is to substitute a general binomial for `\chi` up to a certain maximum degree is reached. The coefficients of the polynomials, are calculated by by collecting terms of the same order in `x` and `y`. After finding `\chi`, the next step is to use `\eta = \xi*h + \chi`, to determine `\xi` and `\eta`. This can be done by dividing `\chi` by `h` which would give `-\xi` as the quotient and `\eta` as the remainder. References ========== - E.S Cheb-Terrab, L.G.S Duarte and L.A,C.P da Mota, Computer Algebra Solving of First Order ODEs Using Symmetry Methods, pp. 8 """ h = match['h'] hy = match['hy'] func = match['func'] x = func.args[0] y = match['y'] xi = Function('xi')(x, func) eta = Function('eta')(x, func) if h.is_rational_function(): schi, schix, schiy = symbols("schi, schix, schiy") cpde = schix + h*schiy - hy*schi num, denom = cancel(cpde).as_numer_denom() deg = Poly(num, x, y).total_degree() chi = Function('chi')(x, y) chix = chi.diff(x) chiy = chi.diff(y) cpde = chix + h*chiy - hy*chi chieq = Symbol("chi") for i in range(1, deg + 1): chieq += Add(*[ Symbol("chi_" + str(power) + "_" + str(i - power))*x**power*y**(i - power) for power in range(i + 1)]) cnum, cden = cancel(cpde.subs({chi : chieq}).doit()).as_numer_denom() cnum = expand(cnum) if cnum.is_polynomial(x, y) and cnum.is_Add: cpoly = Poly(cnum, x, y).as_dict() if cpoly: solsyms = chieq.free_symbols - {x, y} soldict = solve(cpoly.values(), *solsyms) if isinstance(soldict, list): soldict = soldict[0] if any(soldict.values()): chieq = chieq.subs(soldict) dict_ = {sym: 1 for sym in solsyms} chieq = chieq.subs(dict_) # After finding chi, the main aim is to find out # eta, xi by the equation eta = xi*h + chi # One method to set xi, would be rearranging it to # (eta/h) - xi = (chi/h). This would mean dividing # chi by h would give -xi as the quotient and eta # as the remainder. Thanks to Sean Vig for suggesting # this method. xic, etac = div(chieq, h) inf = {eta: etac.subs(y, func), xi: -xic.subs(y, func)} return [inf] def lie_heuristic_function_sum(match, comp=False): r""" This heuristic uses the following two assumptions on `\xi` and `\eta` .. math:: \eta = 0, \xi = f(x) + g(y) .. math:: \eta = f(x) + g(y), \xi = 0 The first assumption of this heuristic holds good if .. math:: \frac{\partial}{\partial y}[(h\frac{\partial^{2}}{ \partial x^{2}}(h^{-1}))^{-1}] is separable in `x` and `y`, 1. The separated factors containing `y` is `\frac{\partial g}{\partial y}`. From this `g(y)` can be determined. 2. The separated factors containing `x` is `f''(x)`. 3. `h\frac{\partial^{2}}{\partial x^{2}}(h^{-1})` equals `\frac{f''(x)}{f(x) + g(y)}`. From this `f(x)` can be determined. The second assumption holds good if `\frac{dy}{dx} = h(x, y)` is rewritten as `\frac{dy}{dx} = \frac{1}{h(y, x)}` and the same properties of the first assumption satisfies. After obtaining `f(x)` and `g(y)`, the coordinates are again interchanged, to get `\eta` as `f(x) + g(y)`. For both assumptions, the constant factors are separated among `g(y)` and `f''(x)`, such that `f''(x)` obtained from 3] is the same as that obtained from 2]. If not possible, then this heuristic fails. References ========== - E.S. Cheb-Terrab, A.D. Roche, Symmetries and First Order ODE Patterns, pp. 7 - pp. 8 """ xieta = [] h = match['h'] func = match['func'] hinv = match['hinv'] x = func.args[0] y = match['y'] xi = Function('xi')(x, func) eta = Function('eta')(x, func) for odefac in [h, hinv]: factor = odefac*((1/odefac).diff(x, 2)) sep = separatevars((1/factor).diff(y), dict=True, symbols=[x, y]) if sep and sep['coeff'] and sep[x].has(x) and sep[y].has(y): k = Dummy("k") try: gy = k*integrate(sep[y], y) except NotImplementedError: pass else: fdd = 1/(k*sep[x]*sep['coeff']) fx = simplify(fdd/factor - gy) check = simplify(fx.diff(x, 2) - fdd) if fx: if not check: fx = fx.subs(k, 1) gy = (gy/k) else: sol = solve(check, k) if sol: sol = sol[0] fx = fx.subs(k, sol) gy = (gy/k)*sol else: continue if odefac == hinv: # Inverse ODE fx = fx.subs(x, y) gy = gy.subs(y, x) etaval = factor_terms(fx + gy) if etaval.is_Mul: etaval = Mul(*[arg for arg in etaval.args if arg.has(x, y)]) if odefac == hinv: # Inverse ODE inf = {eta: etaval.subs(y, func), xi : S.Zero} else: inf = {xi: etaval.subs(y, func), eta : S.Zero} if not comp: return [inf] else: xieta.append(inf) if xieta: return xieta def lie_heuristic_abaco2_similar(match, comp=False): r""" This heuristic uses the following two assumptions on `\xi` and `\eta` .. math:: \eta = g(x), \xi = f(x) .. math:: \eta = f(y), \xi = g(y) For the first assumption, 1. First `\frac{\frac{\partial h}{\partial y}}{\frac{\partial^{2} h}{ \partial yy}}` is calculated. Let us say this value is A 2. If this is constant, then `h` is matched to the form `A(x) + B(x)e^{ \frac{y}{C}}` then, `\frac{e^{\int \frac{A(x)}{C} \,dx}}{B(x)}` gives `f(x)` and `A(x)*f(x)` gives `g(x)` 3. Otherwise `\frac{\frac{\partial A}{\partial X}}{\frac{\partial A}{ \partial Y}} = \gamma` is calculated. If a] `\gamma` is a function of `x` alone b] `\frac{\gamma\frac{\partial h}{\partial y} - \gamma'(x) - \frac{ \partial h}{\partial x}}{h + \gamma} = G` is a function of `x` alone. then, `e^{\int G \,dx}` gives `f(x)` and `-\gamma*f(x)` gives `g(x)` The second assumption holds good if `\frac{dy}{dx} = h(x, y)` is rewritten as `\frac{dy}{dx} = \frac{1}{h(y, x)}` and the same properties of the first assumption satisfies. After obtaining `f(x)` and `g(x)`, the coordinates are again interchanged, to get `\xi` as `f(x^*)` and `\eta` as `g(y^*)` References ========== - E.S. Cheb-Terrab, A.D. Roche, Symmetries and First Order ODE Patterns, pp. 10 - pp. 12 """ h = match['h'] hx = match['hx'] hy = match['hy'] func = match['func'] hinv = match['hinv'] x = func.args[0] y = match['y'] xi = Function('xi')(x, func) eta = Function('eta')(x, func) factor = cancel(h.diff(y)/h.diff(y, 2)) factorx = factor.diff(x) factory = factor.diff(y) if not factor.has(x) and not factor.has(y): A = Wild('A', exclude=[y]) B = Wild('B', exclude=[y]) C = Wild('C', exclude=[x, y]) match = h.match(A + B*exp(y/C)) try: tau = exp(-integrate(match[A]/match[C]), x)/match[B] except NotImplementedError: pass else: gx = match[A]*tau return [{xi: tau, eta: gx}] else: gamma = cancel(factorx/factory) if not gamma.has(y): tauint = cancel((gamma*hy - gamma.diff(x) - hx)/(h + gamma)) if not tauint.has(y): try: tau = exp(integrate(tauint, x)) except NotImplementedError: pass else: gx = -tau*gamma return [{xi: tau, eta: gx}] factor = cancel(hinv.diff(y)/hinv.diff(y, 2)) factorx = factor.diff(x) factory = factor.diff(y) if not factor.has(x) and not factor.has(y): A = Wild('A', exclude=[y]) B = Wild('B', exclude=[y]) C = Wild('C', exclude=[x, y]) match = h.match(A + B*exp(y/C)) try: tau = exp(-integrate(match[A]/match[C]), x)/match[B] except NotImplementedError: pass else: gx = match[A]*tau return [{eta: tau.subs(x, func), xi: gx.subs(x, func)}] else: gamma = cancel(factorx/factory) if not gamma.has(y): tauint = cancel((gamma*hinv.diff(y) - gamma.diff(x) - hinv.diff(x))/( hinv + gamma)) if not tauint.has(y): try: tau = exp(integrate(tauint, x)) except NotImplementedError: pass else: gx = -tau*gamma return [{eta: tau.subs(x, func), xi: gx.subs(x, func)}] def lie_heuristic_abaco2_unique_unknown(match, comp=False): r""" This heuristic assumes the presence of unknown functions or known functions with non-integer powers. 1. A list of all functions and non-integer powers containing x and y 2. Loop over each element `f` in the list, find `\frac{\frac{\partial f}{\partial x}}{ \frac{\partial f}{\partial x}} = R` If it is separable in `x` and `y`, let `X` be the factors containing `x`. Then a] Check if `\xi = X` and `\eta = -\frac{X}{R}` satisfy the PDE. If yes, then return `\xi` and `\eta` b] Check if `\xi = \frac{-R}{X}` and `\eta = -\frac{1}{X}` satisfy the PDE. If yes, then return `\xi` and `\eta` If not, then check if a] :math:`\xi = -R,\eta = 1` b] :math:`\xi = 1, \eta = -\frac{1}{R}` are solutions. References ========== - E.S. Cheb-Terrab, A.D. Roche, Symmetries and First Order ODE Patterns, pp. 10 - pp. 12 """ h = match['h'] hx = match['hx'] hy = match['hy'] func = match['func'] x = func.args[0] y = match['y'] xi = Function('xi')(x, func) eta = Function('eta')(x, func) funclist = [] for atom in h.atoms(Pow): base, exp = atom.as_base_exp() if base.has(x) and base.has(y): if not exp.is_Integer: funclist.append(atom) for function in h.atoms(AppliedUndef): syms = function.free_symbols if x in syms and y in syms: funclist.append(function) for f in funclist: frac = cancel(f.diff(y)/f.diff(x)) sep = separatevars(frac, dict=True, symbols=[x, y]) if sep and sep['coeff']: xitry1 = sep[x] etatry1 = -1/(sep[y]*sep['coeff']) pde1 = etatry1.diff(y)*h - xitry1.diff(x)*h - xitry1*hx - etatry1*hy if not simplify(pde1): return [{xi: xitry1, eta: etatry1.subs(y, func)}] xitry2 = 1/etatry1 etatry2 = 1/xitry1 pde2 = etatry2.diff(x) - (xitry2.diff(y))*h**2 - xitry2*hx - etatry2*hy if not simplify(expand(pde2)): return [{xi: xitry2.subs(y, func), eta: etatry2}] else: etatry = -1/frac pde = etatry.diff(x) + etatry.diff(y)*h - hx - etatry*hy if not simplify(pde): return [{xi: S.One, eta: etatry.subs(y, func)}] xitry = -frac pde = -xitry.diff(x)*h -xitry.diff(y)*h**2 - xitry*hx -hy if not simplify(expand(pde)): return [{xi: xitry.subs(y, func), eta: S.One}] def lie_heuristic_abaco2_unique_general(match, comp=False): r""" This heuristic finds if infinitesimals of the form `\eta = f(x)`, `\xi = g(y)` without making any assumptions on `h`. The complete sequence of steps is given in the paper mentioned below. References ========== - E.S. Cheb-Terrab, A.D. Roche, Symmetries and First Order ODE Patterns, pp. 10 - pp. 12 """ hx = match['hx'] hy = match['hy'] func = match['func'] x = func.args[0] y = match['y'] xi = Function('xi')(x, func) eta = Function('eta')(x, func) A = hx.diff(y) B = hy.diff(y) + hy**2 C = hx.diff(x) - hx**2 if not (A and B and C): return Ax = A.diff(x) Ay = A.diff(y) Axy = Ax.diff(y) Axx = Ax.diff(x) Ayy = Ay.diff(y) D = simplify(2*Axy + hx*Ay - Ax*hy + (hx*hy + 2*A)*A)*A - 3*Ax*Ay if not D: E1 = simplify(3*Ax**2 + ((hx**2 + 2*C)*A - 2*Axx)*A) if E1: E2 = simplify((2*Ayy + (2*B - hy**2)*A)*A - 3*Ay**2) if not E2: E3 = simplify( E1*((28*Ax + 4*hx*A)*A**3 - E1*(hy*A + Ay)) - E1.diff(x)*8*A**4) if not E3: etaval = cancel((4*A**3*(Ax - hx*A) + E1*(hy*A - Ay))/(S(2)*A*E1)) if x not in etaval: try: etaval = exp(integrate(etaval, y)) except NotImplementedError: pass else: xival = -4*A**3*etaval/E1 if y not in xival: return [{xi: xival, eta: etaval.subs(y, func)}] else: E1 = simplify((2*Ayy + (2*B - hy**2)*A)*A - 3*Ay**2) if E1: E2 = simplify( 4*A**3*D - D**2 + E1*((2*Axx - (hx**2 + 2*C)*A)*A - 3*Ax**2)) if not E2: E3 = simplify( -(A*D)*E1.diff(y) + ((E1.diff(x) - hy*D)*A + 3*Ay*D + (A*hx - 3*Ax)*E1)*E1) if not E3: etaval = cancel(((A*hx - Ax)*E1 - (Ay + A*hy)*D)/(S(2)*A*D)) if x not in etaval: try: etaval = exp(integrate(etaval, y)) except NotImplementedError: pass else: xival = -E1*etaval/D if y not in xival: return [{xi: xival, eta: etaval.subs(y, func)}] def lie_heuristic_linear(match, comp=False): r""" This heuristic assumes 1. `\xi = ax + by + c` and 2. `\eta = fx + gy + h` After substituting the following assumptions in the determining PDE, it reduces to .. math:: f + (g - a)h - bh^{2} - (ax + by + c)\frac{\partial h}{\partial x} - (fx + gy + c)\frac{\partial h}{\partial y} Solving the reduced PDE obtained, using the method of characteristics, becomes impractical. The method followed is grouping similar terms and solving the system of linear equations obtained. The difference between the bivariate heuristic is that `h` need not be a rational function in this case. References ========== - E.S. Cheb-Terrab, A.D. Roche, Symmetries and First Order ODE Patterns, pp. 10 - pp. 12 """ h = match['h'] hx = match['hx'] hy = match['hy'] func = match['func'] x = func.args[0] y = match['y'] xi = Function('xi')(x, func) eta = Function('eta')(x, func) coeffdict = {} symbols = numbered_symbols("c", cls=Dummy) symlist = [next(symbols) for _ in islice(symbols, 6)] C0, C1, C2, C3, C4, C5 = symlist pde = C3 + (C4 - C0)*h - (C0*x + C1*y + C2)*hx - (C3*x + C4*y + C5)*hy - C1*h**2 pde, denom = pde.as_numer_denom() pde = powsimp(expand(pde)) if pde.is_Add: terms = pde.args for term in terms: if term.is_Mul: rem = Mul(*[m for m in term.args if not m.has(x, y)]) xypart = term/rem if xypart not in coeffdict: coeffdict[xypart] = rem else: coeffdict[xypart] += rem else: if term not in coeffdict: coeffdict[term] = S.One else: coeffdict[term] += S.One sollist = coeffdict.values() soldict = solve(sollist, symlist) if soldict: if isinstance(soldict, list): soldict = soldict[0] subval = soldict.values() if any(t for t in subval): onedict = dict(zip(symlist, [1]*6)) xival = C0*x + C1*func + C2 etaval = C3*x + C4*func + C5 xival = xival.subs(soldict) etaval = etaval.subs(soldict) xival = xival.subs(onedict) etaval = etaval.subs(onedict) return [{xi: xival, eta: etaval}] def sysode_linear_2eq_order1(match_): x = match_['func'][0].func y = match_['func'][1].func func = match_['func'] fc = match_['func_coeff'] eq = match_['eq'] r = dict() t = list(list(eq[0].atoms(Derivative))[0].atoms(Symbol))[0] for i in range(2): eqs = 0 for terms in Add.make_args(eq[i]): eqs += terms/fc[i,func[i],1] eq[i] = eqs # for equations Eq(a1*diff(x(t),t), a*x(t) + b*y(t) + k1) # and Eq(a2*diff(x(t),t), c*x(t) + d*y(t) + k2) r['a'] = -fc[0,x(t),0]/fc[0,x(t),1] r['c'] = -fc[1,x(t),0]/fc[1,y(t),1] r['b'] = -fc[0,y(t),0]/fc[0,x(t),1] r['d'] = -fc[1,y(t),0]/fc[1,y(t),1] forcing = [S.Zero,S.Zero] for i in range(2): for j in Add.make_args(eq[i]): if not j.has(x(t), y(t)): forcing[i] += j if not (forcing[0].has(t) or forcing[1].has(t)): r['k1'] = forcing[0] r['k2'] = forcing[1] else: raise NotImplementedError("Only homogeneous problems are supported" + " (and constant inhomogeneity)") if match_['type_of_equation'] == 'type6': sol = _linear_2eq_order1_type6(x, y, t, r, eq) if match_['type_of_equation'] == 'type7': sol = _linear_2eq_order1_type7(x, y, t, r, eq) return sol def _linear_2eq_order1_type6(x, y, t, r, eq): r""" The equations of this type of ode are . .. math:: x' = f(t) x + g(t) y .. math:: y' = a [f(t) + a h(t)] x + a [g(t) - h(t)] y This is solved by first multiplying the first equation by `-a` and adding it to the second equation to obtain .. math:: y' - a x' = -a h(t) (y - a x) Setting `U = y - ax` and integrating the equation we arrive at .. math:: y - ax = C_1 e^{-a \int h(t) \,dt} and on substituting the value of y in first equation give rise to first order ODEs. After solving for `x`, we can obtain `y` by substituting the value of `x` in second equation. """ C1, C2, C3, C4 = get_numbered_constants(eq, num=4) p = 0 q = 0 p1 = cancel(r['c']/cancel(r['c']/r['d']).as_numer_denom()[0]) p2 = cancel(r['a']/cancel(r['a']/r['b']).as_numer_denom()[0]) for n, i in enumerate([p1, p2]): for j in Mul.make_args(collect_const(i)): if not j.has(t): q = j if q!=0 and n==0: if ((r['c']/j - r['a'])/(r['b'] - r['d']/j)) == j: p = 1 s = j break if q!=0 and n==1: if ((r['a']/j - r['c'])/(r['d'] - r['b']/j)) == j: p = 2 s = j break if p == 1: equ = diff(x(t),t) - r['a']*x(t) - r['b']*(s*x(t) + C1*exp(-s*Integral(r['b'] - r['d']/s, t))) hint1 = classify_ode(equ)[1] sol1 = dsolve(equ, hint=hint1+'_Integral').rhs sol2 = s*sol1 + C1*exp(-s*Integral(r['b'] - r['d']/s, t)) elif p ==2: equ = diff(y(t),t) - r['c']*y(t) - r['d']*s*y(t) + C1*exp(-s*Integral(r['d'] - r['b']/s, t)) hint1 = classify_ode(equ)[1] sol2 = dsolve(equ, hint=hint1+'_Integral').rhs sol1 = s*sol2 + C1*exp(-s*Integral(r['d'] - r['b']/s, t)) return [Eq(x(t), sol1), Eq(y(t), sol2)] def _linear_2eq_order1_type7(x, y, t, r, eq): r""" The equations of this type of ode are . .. math:: x' = f(t) x + g(t) y .. math:: y' = h(t) x + p(t) y Differentiating the first equation and substituting the value of `y` from second equation will give a second-order linear equation .. math:: g x'' - (fg + gp + g') x' + (fgp - g^{2} h + f g' - f' g) x = 0 This above equation can be easily integrated if following conditions are satisfied. 1. `fgp - g^{2} h + f g' - f' g = 0` 2. `fgp - g^{2} h + f g' - f' g = ag, fg + gp + g' = bg` If first condition is satisfied then it is solved by current dsolve solver and in second case it becomes a constant coefficient differential equation which is also solved by current solver. Otherwise if the above condition fails then, a particular solution is assumed as `x = x_0(t)` and `y = y_0(t)` Then the general solution is expressed as .. math:: x = C_1 x_0(t) + C_2 x_0(t) \int \frac{g(t) F(t) P(t)}{x_0^{2}(t)} \,dt .. math:: y = C_1 y_0(t) + C_2 [\frac{F(t) P(t)}{x_0(t)} + y_0(t) \int \frac{g(t) F(t) P(t)}{x_0^{2}(t)} \,dt] where C1 and C2 are arbitrary constants and .. math:: F(t) = e^{\int f(t) \,dt} , P(t) = e^{\int p(t) \,dt} """ C1, C2, C3, C4 = get_numbered_constants(eq, num=4) e1 = r['a']*r['b']*r['c'] - r['b']**2*r['c'] + r['a']*diff(r['b'],t) - diff(r['a'],t)*r['b'] e2 = r['a']*r['c']*r['d'] - r['b']*r['c']**2 + diff(r['c'],t)*r['d'] - r['c']*diff(r['d'],t) m1 = r['a']*r['b'] + r['b']*r['d'] + diff(r['b'],t) m2 = r['a']*r['c'] + r['c']*r['d'] + diff(r['c'],t) if e1 == 0: sol1 = dsolve(r['b']*diff(x(t),t,t) - m1*diff(x(t),t)).rhs sol2 = dsolve(diff(y(t),t) - r['c']*sol1 - r['d']*y(t)).rhs elif e2 == 0: sol2 = dsolve(r['c']*diff(y(t),t,t) - m2*diff(y(t),t)).rhs sol1 = dsolve(diff(x(t),t) - r['a']*x(t) - r['b']*sol2).rhs elif not (e1/r['b']).has(t) and not (m1/r['b']).has(t): sol1 = dsolve(diff(x(t),t,t) - (m1/r['b'])*diff(x(t),t) - (e1/r['b'])*x(t)).rhs sol2 = dsolve(diff(y(t),t) - r['c']*sol1 - r['d']*y(t)).rhs elif not (e2/r['c']).has(t) and not (m2/r['c']).has(t): sol2 = dsolve(diff(y(t),t,t) - (m2/r['c'])*diff(y(t),t) - (e2/r['c'])*y(t)).rhs sol1 = dsolve(diff(x(t),t) - r['a']*x(t) - r['b']*sol2).rhs else: x0 = Function('x0')(t) # x0 and y0 being particular solutions y0 = Function('y0')(t) F = exp(Integral(r['a'],t)) P = exp(Integral(r['d'],t)) sol1 = C1*x0 + C2*x0*Integral(r['b']*F*P/x0**2, t) sol2 = C1*y0 + C2*(F*P/x0 + y0*Integral(r['b']*F*P/x0**2, t)) return [Eq(x(t), sol1), Eq(y(t), sol2)] def sysode_nonlinear_2eq_order1(match_): func = match_['func'] eq = match_['eq'] fc = match_['func_coeff'] t = list(list(eq[0].atoms(Derivative))[0].atoms(Symbol))[0] if match_['type_of_equation'] == 'type5': sol = _nonlinear_2eq_order1_type5(func, t, eq) return sol x = func[0].func y = func[1].func for i in range(2): eqs = 0 for terms in Add.make_args(eq[i]): eqs += terms/fc[i,func[i],1] eq[i] = eqs if match_['type_of_equation'] == 'type1': sol = _nonlinear_2eq_order1_type1(x, y, t, eq) elif match_['type_of_equation'] == 'type2': sol = _nonlinear_2eq_order1_type2(x, y, t, eq) elif match_['type_of_equation'] == 'type3': sol = _nonlinear_2eq_order1_type3(x, y, t, eq) elif match_['type_of_equation'] == 'type4': sol = _nonlinear_2eq_order1_type4(x, y, t, eq) return sol def _nonlinear_2eq_order1_type1(x, y, t, eq): r""" Equations: .. math:: x' = x^n F(x,y) .. math:: y' = g(y) F(x,y) Solution: .. math:: x = \varphi(y), \int \frac{1}{g(y) F(\varphi(y),y)} \,dy = t + C_2 where if `n \neq 1` .. math:: \varphi = [C_1 + (1-n) \int \frac{1}{g(y)} \,dy]^{\frac{1}{1-n}} if `n = 1` .. math:: \varphi = C_1 e^{\int \frac{1}{g(y)} \,dy} where `C_1` and `C_2` are arbitrary constants. """ C1, C2 = get_numbered_constants(eq, num=2) n = Wild('n', exclude=[x(t),y(t)]) f = Wild('f') u, v = symbols('u, v') r = eq[0].match(diff(x(t),t) - x(t)**n*f) g = ((diff(y(t),t) - eq[1])/r[f]).subs(y(t),v) F = r[f].subs(x(t),u).subs(y(t),v) n = r[n] if n!=1: phi = (C1 + (1-n)*Integral(1/g, v))**(1/(1-n)) else: phi = C1*exp(Integral(1/g, v)) phi = phi.doit() sol2 = solve(Integral(1/(g*F.subs(u,phi)), v).doit() - t - C2, v) sol = [] for sols in sol2: sol.append(Eq(x(t),phi.subs(v, sols))) sol.append(Eq(y(t), sols)) return sol def _nonlinear_2eq_order1_type2(x, y, t, eq): r""" Equations: .. math:: x' = e^{\lambda x} F(x,y) .. math:: y' = g(y) F(x,y) Solution: .. math:: x = \varphi(y), \int \frac{1}{g(y) F(\varphi(y),y)} \,dy = t + C_2 where if `\lambda \neq 0` .. math:: \varphi = -\frac{1}{\lambda} log(C_1 - \lambda \int \frac{1}{g(y)} \,dy) if `\lambda = 0` .. math:: \varphi = C_1 + \int \frac{1}{g(y)} \,dy where `C_1` and `C_2` are arbitrary constants. """ C1, C2 = get_numbered_constants(eq, num=2) n = Wild('n', exclude=[x(t),y(t)]) f = Wild('f') u, v = symbols('u, v') r = eq[0].match(diff(x(t),t) - exp(n*x(t))*f) g = ((diff(y(t),t) - eq[1])/r[f]).subs(y(t),v) F = r[f].subs(x(t),u).subs(y(t),v) n = r[n] if n: phi = -1/n*log(C1 - n*Integral(1/g, v)) else: phi = C1 + Integral(1/g, v) phi = phi.doit() sol2 = solve(Integral(1/(g*F.subs(u,phi)), v).doit() - t - C2, v) sol = [] for sols in sol2: sol.append(Eq(x(t),phi.subs(v, sols))) sol.append(Eq(y(t), sols)) return sol def _nonlinear_2eq_order1_type3(x, y, t, eq): r""" Autonomous system of general form .. math:: x' = F(x,y) .. math:: y' = G(x,y) Assuming `y = y(x, C_1)` where `C_1` is an arbitrary constant is the general solution of the first-order equation .. math:: F(x,y) y'_x = G(x,y) Then the general solution of the original system of equations has the form .. math:: \int \frac{1}{F(x,y(x,C_1))} \,dx = t + C_1 """ C1, C2, C3, C4 = get_numbered_constants(eq, num=4) v = Function('v') u = Symbol('u') f = Wild('f') g = Wild('g') r1 = eq[0].match(diff(x(t),t) - f) r2 = eq[1].match(diff(y(t),t) - g) F = r1[f].subs(x(t), u).subs(y(t), v(u)) G = r2[g].subs(x(t), u).subs(y(t), v(u)) sol2r = dsolve(Eq(diff(v(u), u), G/F)) if isinstance(sol2r, Equality): sol2r = [sol2r] for sol2s in sol2r: sol1 = solve(Integral(1/F.subs(v(u), sol2s.rhs), u).doit() - t - C2, u) sol = [] for sols in sol1: sol.append(Eq(x(t), sols)) sol.append(Eq(y(t), (sol2s.rhs).subs(u, sols))) return sol def _nonlinear_2eq_order1_type4(x, y, t, eq): r""" Equation: .. math:: x' = f_1(x) g_1(y) \phi(x,y,t) .. math:: y' = f_2(x) g_2(y) \phi(x,y,t) First integral: .. math:: \int \frac{f_2(x)}{f_1(x)} \,dx - \int \frac{g_1(y)}{g_2(y)} \,dy = C where `C` is an arbitrary constant. On solving the first integral for `x` (resp., `y` ) and on substituting the resulting expression into either equation of the original solution, one arrives at a first-order equation for determining `y` (resp., `x` ). """ C1, C2 = get_numbered_constants(eq, num=2) u, v = symbols('u, v') U, V = symbols('U, V', cls=Function) f = Wild('f') g = Wild('g') f1 = Wild('f1', exclude=[v,t]) f2 = Wild('f2', exclude=[v,t]) g1 = Wild('g1', exclude=[u,t]) g2 = Wild('g2', exclude=[u,t]) r1 = eq[0].match(diff(x(t),t) - f) r2 = eq[1].match(diff(y(t),t) - g) num, den = ( (r1[f].subs(x(t),u).subs(y(t),v))/ (r2[g].subs(x(t),u).subs(y(t),v))).as_numer_denom() R1 = num.match(f1*g1) R2 = den.match(f2*g2) phi = (r1[f].subs(x(t),u).subs(y(t),v))/num F1 = R1[f1]; F2 = R2[f2] G1 = R1[g1]; G2 = R2[g2] sol1r = solve(Integral(F2/F1, u).doit() - Integral(G1/G2,v).doit() - C1, u) sol2r = solve(Integral(F2/F1, u).doit() - Integral(G1/G2,v).doit() - C1, v) sol = [] for sols in sol1r: sol.append(Eq(y(t), dsolve(diff(V(t),t) - F2.subs(u,sols).subs(v,V(t))*G2.subs(v,V(t))*phi.subs(u,sols).subs(v,V(t))).rhs)) for sols in sol2r: sol.append(Eq(x(t), dsolve(diff(U(t),t) - F1.subs(u,U(t))*G1.subs(v,sols).subs(u,U(t))*phi.subs(v,sols).subs(u,U(t))).rhs)) return set(sol) def _nonlinear_2eq_order1_type5(func, t, eq): r""" Clairaut system of ODEs .. math:: x = t x' + F(x',y') .. math:: y = t y' + G(x',y') The following are solutions of the system `(i)` straight lines: .. math:: x = C_1 t + F(C_1, C_2), y = C_2 t + G(C_1, C_2) where `C_1` and `C_2` are arbitrary constants; `(ii)` envelopes of the above lines; `(iii)` continuously differentiable lines made up from segments of the lines `(i)` and `(ii)`. """ C1, C2 = get_numbered_constants(eq, num=2) f = Wild('f') g = Wild('g') def check_type(x, y): r1 = eq[0].match(t*diff(x(t),t) - x(t) + f) r2 = eq[1].match(t*diff(y(t),t) - y(t) + g) if not (r1 and r2): r1 = eq[0].match(diff(x(t),t) - x(t)/t + f/t) r2 = eq[1].match(diff(y(t),t) - y(t)/t + g/t) if not (r1 and r2): r1 = (-eq[0]).match(t*diff(x(t),t) - x(t) + f) r2 = (-eq[1]).match(t*diff(y(t),t) - y(t) + g) if not (r1 and r2): r1 = (-eq[0]).match(diff(x(t),t) - x(t)/t + f/t) r2 = (-eq[1]).match(diff(y(t),t) - y(t)/t + g/t) return [r1, r2] for func_ in func: if isinstance(func_, list): x = func[0][0].func y = func[0][1].func [r1, r2] = check_type(x, y) if not (r1 and r2): [r1, r2] = check_type(y, x) x, y = y, x x1 = diff(x(t),t); y1 = diff(y(t),t) return {Eq(x(t), C1*t + r1[f].subs(x1,C1).subs(y1,C2)), Eq(y(t), C2*t + r2[g].subs(x1,C1).subs(y1,C2))} def sysode_nonlinear_3eq_order1(match_): x = match_['func'][0].func y = match_['func'][1].func z = match_['func'][2].func eq = match_['eq'] t = list(list(eq[0].atoms(Derivative))[0].atoms(Symbol))[0] if match_['type_of_equation'] == 'type1': sol = _nonlinear_3eq_order1_type1(x, y, z, t, eq) if match_['type_of_equation'] == 'type2': sol = _nonlinear_3eq_order1_type2(x, y, z, t, eq) if match_['type_of_equation'] == 'type3': sol = _nonlinear_3eq_order1_type3(x, y, z, t, eq) if match_['type_of_equation'] == 'type4': sol = _nonlinear_3eq_order1_type4(x, y, z, t, eq) if match_['type_of_equation'] == 'type5': sol = _nonlinear_3eq_order1_type5(x, y, z, t, eq) return sol def _nonlinear_3eq_order1_type1(x, y, z, t, eq): r""" Equations: .. math:: a x' = (b - c) y z, \enspace b y' = (c - a) z x, \enspace c z' = (a - b) x y First Integrals: .. math:: a x^{2} + b y^{2} + c z^{2} = C_1 .. math:: a^{2} x^{2} + b^{2} y^{2} + c^{2} z^{2} = C_2 where `C_1` and `C_2` are arbitrary constants. On solving the integrals for `y` and `z` and on substituting the resulting expressions into the first equation of the system, we arrives at a separable first-order equation on `x`. Similarly doing that for other two equations, we will arrive at first order equation on `y` and `z` too. References ========== -http://eqworld.ipmnet.ru/en/solutions/sysode/sode0401.pdf """ C1, C2 = get_numbered_constants(eq, num=2) u, v, w = symbols('u, v, w') p = Wild('p', exclude=[x(t), y(t), z(t), t]) q = Wild('q', exclude=[x(t), y(t), z(t), t]) s = Wild('s', exclude=[x(t), y(t), z(t), t]) r = (diff(x(t),t) - eq[0]).match(p*y(t)*z(t)) r.update((diff(y(t),t) - eq[1]).match(q*z(t)*x(t))) r.update((diff(z(t),t) - eq[2]).match(s*x(t)*y(t))) n1, d1 = r[p].as_numer_denom() n2, d2 = r[q].as_numer_denom() n3, d3 = r[s].as_numer_denom() val = solve([n1*u-d1*v+d1*w, d2*u+n2*v-d2*w, d3*u-d3*v-n3*w],[u,v]) vals = [val[v], val[u]] c = lcm(vals[0].as_numer_denom()[1], vals[1].as_numer_denom()[1]) b = vals[0].subs(w, c) a = vals[1].subs(w, c) y_x = sqrt(((c*C1-C2) - a*(c-a)*x(t)**2)/(b*(c-b))) z_x = sqrt(((b*C1-C2) - a*(b-a)*x(t)**2)/(c*(b-c))) z_y = sqrt(((a*C1-C2) - b*(a-b)*y(t)**2)/(c*(a-c))) x_y = sqrt(((c*C1-C2) - b*(c-b)*y(t)**2)/(a*(c-a))) x_z = sqrt(((b*C1-C2) - c*(b-c)*z(t)**2)/(a*(b-a))) y_z = sqrt(((a*C1-C2) - c*(a-c)*z(t)**2)/(b*(a-b))) sol1 = dsolve(a*diff(x(t),t) - (b-c)*y_x*z_x) sol2 = dsolve(b*diff(y(t),t) - (c-a)*z_y*x_y) sol3 = dsolve(c*diff(z(t),t) - (a-b)*x_z*y_z) return [sol1, sol2, sol3] def _nonlinear_3eq_order1_type2(x, y, z, t, eq): r""" Equations: .. math:: a x' = (b - c) y z f(x, y, z, t) .. math:: b y' = (c - a) z x f(x, y, z, t) .. math:: c z' = (a - b) x y f(x, y, z, t) First Integrals: .. math:: a x^{2} + b y^{2} + c z^{2} = C_1 .. math:: a^{2} x^{2} + b^{2} y^{2} + c^{2} z^{2} = C_2 where `C_1` and `C_2` are arbitrary constants. On solving the integrals for `y` and `z` and on substituting the resulting expressions into the first equation of the system, we arrives at a first-order differential equations on `x`. Similarly doing that for other two equations we will arrive at first order equation on `y` and `z`. References ========== -http://eqworld.ipmnet.ru/en/solutions/sysode/sode0402.pdf """ C1, C2 = get_numbered_constants(eq, num=2) u, v, w = symbols('u, v, w') p = Wild('p', exclude=[x(t), y(t), z(t), t]) q = Wild('q', exclude=[x(t), y(t), z(t), t]) s = Wild('s', exclude=[x(t), y(t), z(t), t]) f = Wild('f') r1 = (diff(x(t),t) - eq[0]).match(y(t)*z(t)*f) r = collect_const(r1[f]).match(p*f) r.update(((diff(y(t),t) - eq[1])/r[f]).match(q*z(t)*x(t))) r.update(((diff(z(t),t) - eq[2])/r[f]).match(s*x(t)*y(t))) n1, d1 = r[p].as_numer_denom() n2, d2 = r[q].as_numer_denom() n3, d3 = r[s].as_numer_denom() val = solve([n1*u-d1*v+d1*w, d2*u+n2*v-d2*w, -d3*u+d3*v+n3*w],[u,v]) vals = [val[v], val[u]] c = lcm(vals[0].as_numer_denom()[1], vals[1].as_numer_denom()[1]) a = vals[0].subs(w, c) b = vals[1].subs(w, c) y_x = sqrt(((c*C1-C2) - a*(c-a)*x(t)**2)/(b*(c-b))) z_x = sqrt(((b*C1-C2) - a*(b-a)*x(t)**2)/(c*(b-c))) z_y = sqrt(((a*C1-C2) - b*(a-b)*y(t)**2)/(c*(a-c))) x_y = sqrt(((c*C1-C2) - b*(c-b)*y(t)**2)/(a*(c-a))) x_z = sqrt(((b*C1-C2) - c*(b-c)*z(t)**2)/(a*(b-a))) y_z = sqrt(((a*C1-C2) - c*(a-c)*z(t)**2)/(b*(a-b))) sol1 = dsolve(a*diff(x(t),t) - (b-c)*y_x*z_x*r[f]) sol2 = dsolve(b*diff(y(t),t) - (c-a)*z_y*x_y*r[f]) sol3 = dsolve(c*diff(z(t),t) - (a-b)*x_z*y_z*r[f]) return [sol1, sol2, sol3] def _nonlinear_3eq_order1_type3(x, y, z, t, eq): r""" Equations: .. math:: x' = c F_2 - b F_3, \enspace y' = a F_3 - c F_1, \enspace z' = b F_1 - a F_2 where `F_n = F_n(x, y, z, t)`. 1. First Integral: .. math:: a x + b y + c z = C_1, where C is an arbitrary constant. 2. If we assume function `F_n` to be independent of `t`,i.e, `F_n` = `F_n (x, y, z)` Then, on eliminating `t` and `z` from the first two equation of the system, one arrives at the first-order equation .. math:: \frac{dy}{dx} = \frac{a F_3 (x, y, z) - c F_1 (x, y, z)}{c F_2 (x, y, z) - b F_3 (x, y, z)} where `z = \frac{1}{c} (C_1 - a x - b y)` References ========== -http://eqworld.ipmnet.ru/en/solutions/sysode/sode0404.pdf """ C1 = get_numbered_constants(eq, num=1) u, v, w = symbols('u, v, w') fu, fv, fw = symbols('u, v, w', cls=Function) p = Wild('p', exclude=[x(t), y(t), z(t), t]) q = Wild('q', exclude=[x(t), y(t), z(t), t]) s = Wild('s', exclude=[x(t), y(t), z(t), t]) F1, F2, F3 = symbols('F1, F2, F3', cls=Wild) r1 = (diff(x(t), t) - eq[0]).match(F2-F3) r = collect_const(r1[F2]).match(s*F2) r.update(collect_const(r1[F3]).match(q*F3)) if eq[1].has(r[F2]) and not eq[1].has(r[F3]): r[F2], r[F3] = r[F3], r[F2] r[s], r[q] = -r[q], -r[s] r.update((diff(y(t), t) - eq[1]).match(p*r[F3] - r[s]*F1)) a = r[p]; b = r[q]; c = r[s] F1 = r[F1].subs(x(t), u).subs(y(t),v).subs(z(t), w) F2 = r[F2].subs(x(t), u).subs(y(t),v).subs(z(t), w) F3 = r[F3].subs(x(t), u).subs(y(t),v).subs(z(t), w) z_xy = (C1-a*u-b*v)/c y_zx = (C1-a*u-c*w)/b x_yz = (C1-b*v-c*w)/a y_x = dsolve(diff(fv(u),u) - ((a*F3-c*F1)/(c*F2-b*F3)).subs(w,z_xy).subs(v,fv(u))).rhs z_x = dsolve(diff(fw(u),u) - ((b*F1-a*F2)/(c*F2-b*F3)).subs(v,y_zx).subs(w,fw(u))).rhs z_y = dsolve(diff(fw(v),v) - ((b*F1-a*F2)/(a*F3-c*F1)).subs(u,x_yz).subs(w,fw(v))).rhs x_y = dsolve(diff(fu(v),v) - ((c*F2-b*F3)/(a*F3-c*F1)).subs(w,z_xy).subs(u,fu(v))).rhs y_z = dsolve(diff(fv(w),w) - ((a*F3-c*F1)/(b*F1-a*F2)).subs(u,x_yz).subs(v,fv(w))).rhs x_z = dsolve(diff(fu(w),w) - ((c*F2-b*F3)/(b*F1-a*F2)).subs(v,y_zx).subs(u,fu(w))).rhs sol1 = dsolve(diff(fu(t),t) - (c*F2 - b*F3).subs(v,y_x).subs(w,z_x).subs(u,fu(t))).rhs sol2 = dsolve(diff(fv(t),t) - (a*F3 - c*F1).subs(u,x_y).subs(w,z_y).subs(v,fv(t))).rhs sol3 = dsolve(diff(fw(t),t) - (b*F1 - a*F2).subs(u,x_z).subs(v,y_z).subs(w,fw(t))).rhs return [sol1, sol2, sol3] def _nonlinear_3eq_order1_type4(x, y, z, t, eq): r""" Equations: .. math:: x' = c z F_2 - b y F_3, \enspace y' = a x F_3 - c z F_1, \enspace z' = b y F_1 - a x F_2 where `F_n = F_n (x, y, z, t)` 1. First integral: .. math:: a x^{2} + b y^{2} + c z^{2} = C_1 where `C` is an arbitrary constant. 2. Assuming the function `F_n` is independent of `t`: `F_n = F_n (x, y, z)`. Then on eliminating `t` and `z` from the first two equations of the system, one arrives at the first-order equation .. math:: \frac{dy}{dx} = \frac{a x F_3 (x, y, z) - c z F_1 (x, y, z)} {c z F_2 (x, y, z) - b y F_3 (x, y, z)} where `z = \pm \sqrt{\frac{1}{c} (C_1 - a x^{2} - b y^{2})}` References ========== -http://eqworld.ipmnet.ru/en/solutions/sysode/sode0405.pdf """ C1 = get_numbered_constants(eq, num=1) u, v, w = symbols('u, v, w') p = Wild('p', exclude=[x(t), y(t), z(t), t]) q = Wild('q', exclude=[x(t), y(t), z(t), t]) s = Wild('s', exclude=[x(t), y(t), z(t), t]) F1, F2, F3 = symbols('F1, F2, F3', cls=Wild) r1 = eq[0].match(diff(x(t),t) - z(t)*F2 + y(t)*F3) r = collect_const(r1[F2]).match(s*F2) r.update(collect_const(r1[F3]).match(q*F3)) if eq[1].has(r[F2]) and not eq[1].has(r[F3]): r[F2], r[F3] = r[F3], r[F2] r[s], r[q] = -r[q], -r[s] r.update((diff(y(t),t) - eq[1]).match(p*x(t)*r[F3] - r[s]*z(t)*F1)) a = r[p]; b = r[q]; c = r[s] F1 = r[F1].subs(x(t),u).subs(y(t),v).subs(z(t),w) F2 = r[F2].subs(x(t),u).subs(y(t),v).subs(z(t),w) F3 = r[F3].subs(x(t),u).subs(y(t),v).subs(z(t),w) x_yz = sqrt((C1 - b*v**2 - c*w**2)/a) y_zx = sqrt((C1 - c*w**2 - a*u**2)/b) z_xy = sqrt((C1 - a*u**2 - b*v**2)/c) y_x = dsolve(diff(v(u),u) - ((a*u*F3-c*w*F1)/(c*w*F2-b*v*F3)).subs(w,z_xy).subs(v,v(u))).rhs z_x = dsolve(diff(w(u),u) - ((b*v*F1-a*u*F2)/(c*w*F2-b*v*F3)).subs(v,y_zx).subs(w,w(u))).rhs z_y = dsolve(diff(w(v),v) - ((b*v*F1-a*u*F2)/(a*u*F3-c*w*F1)).subs(u,x_yz).subs(w,w(v))).rhs x_y = dsolve(diff(u(v),v) - ((c*w*F2-b*v*F3)/(a*u*F3-c*w*F1)).subs(w,z_xy).subs(u,u(v))).rhs y_z = dsolve(diff(v(w),w) - ((a*u*F3-c*w*F1)/(b*v*F1-a*u*F2)).subs(u,x_yz).subs(v,v(w))).rhs x_z = dsolve(diff(u(w),w) - ((c*w*F2-b*v*F3)/(b*v*F1-a*u*F2)).subs(v,y_zx).subs(u,u(w))).rhs sol1 = dsolve(diff(u(t),t) - (c*w*F2 - b*v*F3).subs(v,y_x).subs(w,z_x).subs(u,u(t))).rhs sol2 = dsolve(diff(v(t),t) - (a*u*F3 - c*w*F1).subs(u,x_y).subs(w,z_y).subs(v,v(t))).rhs sol3 = dsolve(diff(w(t),t) - (b*v*F1 - a*u*F2).subs(u,x_z).subs(v,y_z).subs(w,w(t))).rhs return [sol1, sol2, sol3] def _nonlinear_3eq_order1_type5(x, y, z, t, eq): r""" .. math:: x' = x (c F_2 - b F_3), \enspace y' = y (a F_3 - c F_1), \enspace z' = z (b F_1 - a F_2) where `F_n = F_n (x, y, z, t)` and are arbitrary functions. First Integral: .. math:: \left|x\right|^{a} \left|y\right|^{b} \left|z\right|^{c} = C_1 where `C` is an arbitrary constant. If the function `F_n` is independent of `t`, then, by eliminating `t` and `z` from the first two equations of the system, one arrives at a first-order equation. References ========== -http://eqworld.ipmnet.ru/en/solutions/sysode/sode0406.pdf """ C1 = get_numbered_constants(eq, num=1) u, v, w = symbols('u, v, w') fu, fv, fw = symbols('u, v, w', cls=Function) p = Wild('p', exclude=[x(t), y(t), z(t), t]) q = Wild('q', exclude=[x(t), y(t), z(t), t]) s = Wild('s', exclude=[x(t), y(t), z(t), t]) F1, F2, F3 = symbols('F1, F2, F3', cls=Wild) r1 = eq[0].match(diff(x(t), t) - x(t)*F2 + x(t)*F3) r = collect_const(r1[F2]).match(s*F2) r.update(collect_const(r1[F3]).match(q*F3)) if eq[1].has(r[F2]) and not eq[1].has(r[F3]): r[F2], r[F3] = r[F3], r[F2] r[s], r[q] = -r[q], -r[s] r.update((diff(y(t), t) - eq[1]).match(y(t)*(p*r[F3] - r[s]*F1))) a = r[p]; b = r[q]; c = r[s] F1 = r[F1].subs(x(t), u).subs(y(t), v).subs(z(t), w) F2 = r[F2].subs(x(t), u).subs(y(t), v).subs(z(t), w) F3 = r[F3].subs(x(t), u).subs(y(t), v).subs(z(t), w) x_yz = (C1*v**-b*w**-c)**-a y_zx = (C1*w**-c*u**-a)**-b z_xy = (C1*u**-a*v**-b)**-c y_x = dsolve(diff(fv(u), u) - ((v*(a*F3 - c*F1))/(u*(c*F2 - b*F3))).subs(w, z_xy).subs(v, fv(u))).rhs z_x = dsolve(diff(fw(u), u) - ((w*(b*F1 - a*F2))/(u*(c*F2 - b*F3))).subs(v, y_zx).subs(w, fw(u))).rhs z_y = dsolve(diff(fw(v), v) - ((w*(b*F1 - a*F2))/(v*(a*F3 - c*F1))).subs(u, x_yz).subs(w, fw(v))).rhs x_y = dsolve(diff(fu(v), v) - ((u*(c*F2 - b*F3))/(v*(a*F3 - c*F1))).subs(w, z_xy).subs(u, fu(v))).rhs y_z = dsolve(diff(fv(w), w) - ((v*(a*F3 - c*F1))/(w*(b*F1 - a*F2))).subs(u, x_yz).subs(v, fv(w))).rhs x_z = dsolve(diff(fu(w), w) - ((u*(c*F2 - b*F3))/(w*(b*F1 - a*F2))).subs(v, y_zx).subs(u, fu(w))).rhs sol1 = dsolve(diff(fu(t), t) - (u*(c*F2 - b*F3)).subs(v, y_x).subs(w, z_x).subs(u, fu(t))).rhs sol2 = dsolve(diff(fv(t), t) - (v*(a*F3 - c*F1)).subs(u, x_y).subs(w, z_y).subs(v, fv(t))).rhs sol3 = dsolve(diff(fw(t), t) - (w*(b*F1 - a*F2)).subs(u, x_z).subs(v, y_z).subs(w, fw(t))).rhs return [sol1, sol2, sol3] #This import is written at the bottom to avoid circular imports. from .single import (NthAlgebraic, Factorable, FirstLinear, AlmostLinear, Bernoulli, SingleODEProblem, SingleODESolver, RiccatiSpecial, SecondNonlinearAutonomousConserved, FirstExact, Liouville, Separable, SeparableReduced, HomogeneousCoeffSubsDepDivIndep, HomogeneousCoeffSubsIndepDivDep, HomogeneousCoeffBest, LinearCoefficients)
0a2aaa538fd94130c76242f69aa0b8ce8422ae65839343817fb8c48dbf4a5a73
# # This is the module for ODE solver classes for single ODEs. # import typing if typing.TYPE_CHECKING: from typing import ClassVar from typing import Dict, Type from typing import Iterator, List, Optional from sympy.core import Add, S, Pow from sympy.core.exprtools import factor_terms from sympy.core.expr import Expr from sympy.core.function import AppliedUndef, Derivative, Function, expand, Subs, _mexpand from sympy.core.numbers import Float, zoo from sympy.core.relational import Equality, Eq from sympy.core.symbol import Symbol, Dummy, Wild from sympy.core.mul import Mul from sympy.functions import exp, sqrt, tan, log from sympy.integrals import Integral from sympy.polys.polytools import cancel, factor from sympy.simplify import collect, simplify, separatevars, logcombine from sympy.simplify.radsimp import fraction from sympy.utilities import numbered_symbols from sympy.solvers.solvers import solve from sympy.solvers.deutils import ode_order, _preprocess class ODEMatchError(NotImplementedError): """Raised if a SingleODESolver is asked to solve an ODE it does not match""" pass def cached_property(func): '''Decorator to cache property method''' attrname = '_' + func.__name__ def propfunc(self): val = getattr(self, attrname, None) if val is None: val = func(self) setattr(self, attrname, val) return val return property(propfunc) class SingleODEProblem: """Represents an ordinary differential equation (ODE) This class is used internally in the by dsolve and related functions/classes so that properties of an ODE can be computed efficiently. Examples ======== This class is used internally by dsolve. To instantiate an instance directly first define an ODE problem: >>> from sympy import Function, Symbol >>> x = Symbol('x') >>> f = Function('f') >>> eq = f(x).diff(x, 2) Now you can create a SingleODEProblem instance and query its properties: >>> from sympy.solvers.ode.single import SingleODEProblem >>> problem = SingleODEProblem(f(x).diff(x), f(x), x) >>> problem.eq Derivative(f(x), x) >>> problem.func f(x) >>> problem.sym x """ # Instance attributes: eq = None # type: Expr func = None # type: AppliedUndef sym = None # type: Symbol _order = None # type: int _eq_expanded = None # type: Expr _eq_preprocessed = None # type: Expr def __init__(self, eq, func, sym, prep=True): assert isinstance(eq, Expr) assert isinstance(func, AppliedUndef) assert isinstance(sym, Symbol) assert isinstance(prep, bool) self.eq = eq self.func = func self.sym = sym self.prep = prep @cached_property def order(self) -> int: return ode_order(self.eq, self.func) @cached_property def eq_preprocessed(self) -> Expr: return self._get_eq_preprocessed() @cached_property def eq_expanded(self) -> Expr: return expand(self.eq_preprocessed) def _get_eq_preprocessed(self) -> Expr: if self.prep: process_eq, process_func = _preprocess(self.eq, self.func) if process_func != self.func: raise ValueError else: process_eq = self.eq return process_eq def get_numbered_constants(self, num=1, start=1, prefix='C') -> List[Symbol]: """ Returns a list of constants that do not occur in eq already. """ ncs = self.iter_numbered_constants(start, prefix) Cs = [next(ncs) for i in range(num)] return Cs def iter_numbered_constants(self, start=1, prefix='C') -> Iterator[Symbol]: """ Returns an iterator of constants that do not occur in eq already. """ atom_set = self.eq.free_symbols func_set = self.eq.atoms(Function) if func_set: atom_set |= {Symbol(str(f.func)) for f in func_set} return numbered_symbols(start=start, prefix=prefix, exclude=atom_set) @cached_property def is_autonomous(self): u = Dummy('u') x = self.sym syms = self.eq.subs(self.func, u).free_symbols return x not in syms # TODO: Add methods that can be used by many ODE solvers: # order # is_linear() # get_linear_coefficients() # eq_prepared (the ODE in prepared form) class SingleODESolver: """ Base class for Single ODE solvers. Subclasses should implement the _matches and _get_general_solution methods. This class is not intended to be instantiated directly but its subclasses are as part of dsolve. Examples ======== You can use a subclass of SingleODEProblem to solve a particular type of ODE. We first define a particular ODE problem: >>> from sympy import Function, Symbol >>> x = Symbol('x') >>> f = Function('f') >>> eq = f(x).diff(x, 2) Now we solve this problem using the NthAlgebraic solver which is a subclass of SingleODESolver: >>> from sympy.solvers.ode.single import NthAlgebraic, SingleODEProblem >>> problem = SingleODEProblem(eq, f(x), x) >>> solver = NthAlgebraic(problem) >>> solver.get_general_solution() [Eq(f(x), _C*x + _C)] The normal way to solve an ODE is to use dsolve (which would use NthAlgebraic and other solvers internally). When using dsolve a number of other things are done such as evaluating integrals, simplifying the solution and renumbering the constants: >>> from sympy import dsolve >>> dsolve(eq, hint='nth_algebraic') Eq(f(x), C1 + C2*x) """ # Subclasses should store the hint name (the argument to dsolve) in this # attribute hint = None # type: ClassVar[str] # Subclasses should define this to indicate if they support an _Integral # hint. has_integral = None # type: ClassVar[bool] # The ODE to be solved ode_problem = None # type: SingleODEProblem # Cache whether or not the equation has matched the method _matched = None # type: Optional[bool] # Subclasses should store in this attribute the list of order(s) of ODE # that subclass can solve or leave it to None if not specific to any order order = None # type: Optional[list] def __init__(self, ode_problem): self.ode_problem = ode_problem def matches(self) -> bool: if self.order is not None and self.ode_problem.order not in self.order: self._matched = False return self._matched if self._matched is None: self._matched = self._matches() return self._matched def get_general_solution(self, *, simplify: bool = True) -> List[Equality]: if not self.matches(): msg = "%s solver can not solve:\n%s" raise ODEMatchError(msg % (self.hint, self.ode_problem.eq)) return self._get_general_solution(simplify_flag=simplify) def _matches(self) -> bool: msg = "Subclasses of SingleODESolver should implement matches." raise NotImplementedError(msg) def _get_general_solution(self, *, simplify_flag: bool = True) -> List[Equality]: msg = "Subclasses of SingleODESolver should implement get_general_solution." raise NotImplementedError(msg) class SinglePatternODESolver(SingleODESolver): '''Superclass for ODE solvers based on pattern matching''' def wilds(self): prob = self.ode_problem f = prob.func.func x = prob.sym order = prob.order return self._wilds(f, x, order) def wilds_match(self): match = self._wilds_match return [match.get(w, S.Zero) for w in self.wilds()] def _matches(self): eq = self.ode_problem.eq_expanded f = self.ode_problem.func.func x = self.ode_problem.sym order = self.ode_problem.order df = f(x).diff(x, order) if order not in [1, 2]: return False pattern = self._equation(f(x), x, order) if not pattern.coeff(df).has(Wild): eq = expand(eq / eq.coeff(df)) eq = eq.collect([f(x).diff(x), f(x)], func = cancel) self._wilds_match = match = eq.match(pattern) if match is not None: return self._verify(f(x)) return False def _verify(self, fx) -> bool: return True def _wilds(self, f, x, order): msg = "Subclasses of SingleODESolver should implement _wilds" raise NotImplementedError(msg) def _equation(self, fx, x, order): msg = "Subclasses of SingleODESolver should implement _equation" raise NotImplementedError(msg) class NthAlgebraic(SingleODESolver): r""" Solves an `n`\th order ordinary differential equation using algebra and integrals. There is no general form for the kind of equation that this can solve. The the equation is solved algebraically treating differentiation as an invertible algebraic function. Examples ======== >>> from sympy import Function, dsolve, Eq >>> from sympy.abc import x >>> f = Function('f') >>> eq = Eq(f(x) * (f(x).diff(x)**2 - 1), 0) >>> dsolve(eq, f(x), hint='nth_algebraic') [Eq(f(x), 0), Eq(f(x), C1 - x), Eq(f(x), C1 + x)] Note that this solver can return algebraic solutions that do not have any integration constants (f(x) = 0 in the above example). """ hint = 'nth_algebraic' has_integral = True # nth_algebraic_Integral hint def _matches(self): r""" Matches any differential equation that nth_algebraic can solve. Uses `sympy.solve` but teaches it how to integrate derivatives. This involves calling `sympy.solve` and does most of the work of finding a solution (apart from evaluating the integrals). """ eq = self.ode_problem.eq func = self.ode_problem.func var = self.ode_problem.sym # Derivative that solve can handle: diffx = self._get_diffx(var) # Replace derivatives wrt the independent variable with diffx def replace(eq, var): def expand_diffx(*args): differand, diffs = args[0], args[1:] toreplace = differand for v, n in diffs: for _ in range(n): if v == var: toreplace = diffx(toreplace) else: toreplace = Derivative(toreplace, v) return toreplace return eq.replace(Derivative, expand_diffx) # Restore derivatives in solution afterwards def unreplace(eq, var): return eq.replace(diffx, lambda e: Derivative(e, var)) subs_eqn = replace(eq, var) try: # turn off simplification to protect Integrals that have # _t instead of fx in them and would otherwise factor # as t_*Integral(1, x) solns = solve(subs_eqn, func, simplify=False) except NotImplementedError: solns = [] solns = [simplify(unreplace(soln, var)) for soln in solns] solns = [Equality(func, soln) for soln in solns] self.solutions = solns return len(solns) != 0 def _get_general_solution(self, *, simplify_flag: bool = True): return self.solutions # This needs to produce an invertible function but the inverse depends # which variable we are integrating with respect to. Since the class can # be stored in cached results we need to ensure that we always get the # same class back for each particular integration variable so we store these # classes in a global dict: _diffx_stored = {} # type: Dict[Symbol, Type[Function]] @staticmethod def _get_diffx(var): diffcls = NthAlgebraic._diffx_stored.get(var, None) if diffcls is None: # A class that behaves like Derivative wrt var but is "invertible". class diffx(Function): def inverse(self): # don't use integrate here because fx has been replaced by _t # in the equation; integrals will not be correct while solve # is at work. return lambda expr: Integral(expr, var) + Dummy('C') diffcls = NthAlgebraic._diffx_stored.setdefault(var, diffx) return diffcls class FirstExact(SinglePatternODESolver): r""" Solves 1st order exact ordinary differential equations. A 1st order differential equation is called exact if it is the total differential of a function. That is, the differential equation .. math:: P(x, y) \,\partial{}x + Q(x, y) \,\partial{}y = 0 is exact if there is some function `F(x, y)` such that `P(x, y) = \partial{}F/\partial{}x` and `Q(x, y) = \partial{}F/\partial{}y`. It can be shown that a necessary and sufficient condition for a first order ODE to be exact is that `\partial{}P/\partial{}y = \partial{}Q/\partial{}x`. Then, the solution will be as given below:: >>> from sympy import Function, Eq, Integral, symbols, pprint >>> x, y, t, x0, y0, C1= symbols('x,y,t,x0,y0,C1') >>> P, Q, F= map(Function, ['P', 'Q', 'F']) >>> pprint(Eq(Eq(F(x, y), Integral(P(t, y), (t, x0, x)) + ... Integral(Q(x0, t), (t, y0, y))), C1)) x y / / | | F(x, y) = | P(t, y) dt + | Q(x0, t) dt = C1 | | / / x0 y0 Where the first partials of `P` and `Q` exist and are continuous in a simply connected region. A note: SymPy currently has no way to represent inert substitution on an expression, so the hint ``1st_exact_Integral`` will return an integral with `dy`. This is supposed to represent the function that you are solving for. Examples ======== >>> from sympy import Function, dsolve, cos, sin >>> from sympy.abc import x >>> f = Function('f') >>> dsolve(cos(f(x)) - (x*sin(f(x)) - f(x)**2)*f(x).diff(x), ... f(x), hint='1st_exact') Eq(x*cos(f(x)) + f(x)**3/3, C1) References ========== - https://en.wikipedia.org/wiki/Exact_differential_equation - M. Tenenbaum & H. Pollard, "Ordinary Differential Equations", Dover 1963, pp. 73 # indirect doctest """ hint = "1st_exact" has_integral = True order = [1] def _wilds(self, f, x, order): P = Wild('P', exclude=[f(x).diff(x)]) Q = Wild('Q', exclude=[f(x).diff(x)]) return P, Q def _equation(self, fx, x, order): P, Q = self.wilds() return P + Q*fx.diff(x) def _verify(self, fx) -> bool: P, Q = self.wilds() x = self.ode_problem.sym y = Dummy('y') m, n = self.wilds_match() m = m.subs(fx, y) n = n.subs(fx, y) numerator = cancel(m.diff(y) - n.diff(x)) if numerator.is_zero: # Is exact return True else: # The following few conditions try to convert a non-exact # differential equation into an exact one. # References: # 1. Differential equations with applications # and historical notes - George E. Simmons # 2. https://math.okstate.edu/people/binegar/2233-S99/2233-l12.pdf factor_n = cancel(numerator/n) factor_m = cancel(-numerator/m) if y not in factor_n.free_symbols: # If (dP/dy - dQ/dx) / Q = f(x) # then exp(integral(f(x))*equation becomes exact factor = factor_n integration_variable = x elif x not in factor_m.free_symbols: # If (dP/dy - dQ/dx) / -P = f(y) # then exp(integral(f(y))*equation becomes exact factor = factor_m integration_variable = y else: # Couldn't convert to exact return False factor = exp(Integral(factor, integration_variable)) m *= factor n *= factor self._wilds_match[P] = m.subs(y, fx) self._wilds_match[Q] = n.subs(y, fx) return True def _get_general_solution(self, *, simplify_flag: bool = True): m, n = self.wilds_match() fx = self.ode_problem.func x = self.ode_problem.sym (C1,) = self.ode_problem.get_numbered_constants(num=1) y = Dummy('y') m = m.subs(fx, y) n = n.subs(fx, y) gen_sol = Eq(Subs(Integral(m, x) + Integral(n - Integral(m, x).diff(y), y), y, fx), C1) return [gen_sol] class FirstLinear(SinglePatternODESolver): r""" Solves 1st order linear differential equations. These are differential equations of the form .. math:: dy/dx + P(x) y = Q(x)\text{.} These kinds of differential equations can be solved in a general way. The integrating factor `e^{\int P(x) \,dx}` will turn the equation into a separable equation. The general solution is:: >>> from sympy import Function, dsolve, Eq, pprint, diff, sin >>> from sympy.abc import x >>> f, P, Q = map(Function, ['f', 'P', 'Q']) >>> genform = Eq(f(x).diff(x) + P(x)*f(x), Q(x)) >>> pprint(genform) d P(x)*f(x) + --(f(x)) = Q(x) dx >>> pprint(dsolve(genform, f(x), hint='1st_linear_Integral')) / / \ | | | | | / | / | | | | | | | | P(x) dx | - | P(x) dx | | | | | | | / | / f(x) = |C1 + | Q(x)*e dx|*e | | | \ / / Examples ======== >>> f = Function('f') >>> pprint(dsolve(Eq(x*diff(f(x), x) - f(x), x**2*sin(x)), ... f(x), '1st_linear')) f(x) = x*(C1 - cos(x)) References ========== - https://en.wikipedia.org/wiki/Linear_differential_equation#First_order_equation - M. Tenenbaum & H. Pollard, "Ordinary Differential Equations", Dover 1963, pp. 92 # indirect doctest """ hint = '1st_linear' has_integral = True order = [1] def _wilds(self, f, x, order): P = Wild('P', exclude=[f(x)]) Q = Wild('Q', exclude=[f(x), f(x).diff(x)]) return P, Q def _equation(self, fx, x, order): P, Q = self.wilds() return fx.diff(x) + P*fx - Q def _get_general_solution(self, *, simplify_flag: bool = True): P, Q = self.wilds_match() fx = self.ode_problem.func x = self.ode_problem.sym (C1,) = self.ode_problem.get_numbered_constants(num=1) gensol = Eq(fx, ((C1 + Integral(Q*exp(Integral(P, x)),x)) * exp(-Integral(P, x)))) return [gensol] class AlmostLinear(SinglePatternODESolver): r""" Solves an almost-linear differential equation. The general form of an almost linear differential equation is .. math:: a(x) g'(f(x)) f'(x) + b(x) g(f(x)) + c(x) Here `f(x)` is the function to be solved for (the dependent variable). The substitution `g(f(x)) = u(x)` leads to a linear differential equation for `u(x)` of the form `a(x) u' + b(x) u + c(x) = 0`. This can be solved for `u(x)` by the `first_linear` hint and then `f(x)` is found by solving `g(f(x)) = u(x)`. See Also ======== :obj:`sympy.solvers.ode.single.FirstLinear` Examples ======== >>> from sympy import Function, pprint, sin, cos >>> from sympy.solvers.ode import dsolve >>> from sympy.abc import x >>> f = Function('f') >>> d = f(x).diff(x) >>> eq = x*d + x*f(x) + 1 >>> dsolve(eq, f(x), hint='almost_linear') Eq(f(x), (C1 - Ei(x))*exp(-x)) >>> pprint(dsolve(eq, f(x), hint='almost_linear')) -x f(x) = (C1 - Ei(x))*e >>> example = cos(f(x))*f(x).diff(x) + sin(f(x)) + 1 >>> pprint(example) d sin(f(x)) + cos(f(x))*--(f(x)) + 1 dx >>> pprint(dsolve(example, f(x), hint='almost_linear')) / -x \ / -x \ [f(x) = pi - asin\C1*e - 1/, f(x) = asin\C1*e - 1/] References ========== - Joel Moses, "Symbolic Integration - The Stormy Decade", Communications of the ACM, Volume 14, Number 8, August 1971, pp. 558 """ hint = "almost_linear" has_integral = True order = [1] def _wilds(self, f, x, order): P = Wild('P', exclude=[f(x).diff(x)]) Q = Wild('Q', exclude=[f(x).diff(x)]) return P, Q def _equation(self, fx, x, order): P, Q = self.wilds() return P*fx.diff(x) + Q def _verify(self, fx): a, b = self.wilds_match() c, b = b.as_independent(fx) if b.is_Add else (S.Zero, b) # a, b and c are the function a(x), b(x) and c(x) respectively. # c(x) is obtained by separating out b as terms with and without fx i.e, l(y) # The following conditions checks if the given equation is an almost-linear differential equation using the fact that # a(x)*(l(y))' / l(y)' is independent of l(y) if b.diff(fx) != 0 and not simplify(b.diff(fx)/a).has(fx): self.ly = factor_terms(b).as_independent(fx, as_Add=False)[1] # Gives the term containing fx i.e., l(y) self.ax = a / self.ly.diff(fx) self.cx = -c # cx is taken as -c(x) to simplify expression in the solution integral self.bx = factor_terms(b) / self.ly return True return False def _get_general_solution(self, *, simplify_flag: bool = True): x = self.ode_problem.sym (C1,) = self.ode_problem.get_numbered_constants(num=1) gensol = Eq(self.ly, ((C1 + Integral((self.cx/self.ax)*exp(Integral(self.bx/self.ax, x)),x)) * exp(-Integral(self.bx/self.ax, x)))) return [gensol] class Bernoulli(SinglePatternODESolver): r""" Solves Bernoulli differential equations. These are equations of the form .. math:: dy/dx + P(x) y = Q(x) y^n\text{, }n \ne 1`\text{.} The substitution `w = 1/y^{1-n}` will transform an equation of this form into one that is linear (see the docstring of :obj:`~sympy.solvers.ode.single.FirstLinear`). The general solution is:: >>> from sympy import Function, dsolve, Eq, pprint >>> from sympy.abc import x, n >>> f, P, Q = map(Function, ['f', 'P', 'Q']) >>> genform = Eq(f(x).diff(x) + P(x)*f(x), Q(x)*f(x)**n) >>> pprint(genform) d n P(x)*f(x) + --(f(x)) = Q(x)*f (x) dx >>> pprint(dsolve(genform, f(x), hint='Bernoulli_Integral'), num_columns=110) -1 ----- n - 1 // / / \ \ || | | | | || | / | / | / | || | | | | | | | || | (1 - n)* | P(x) dx | (1 - n)* | P(x) dx | (n - 1)* | P(x) dx| || | | | | | | | || | / | / | / | f(x) = ||C1 - n* | Q(x)*e dx + | Q(x)*e dx|*e | || | | | | \\ / / / / Note that the equation is separable when `n = 1` (see the docstring of :obj:`~sympy.solvers.ode.single.Separable`). >>> pprint(dsolve(Eq(f(x).diff(x) + P(x)*f(x), Q(x)*f(x)), f(x), ... hint='separable_Integral')) f(x) / | / | 1 | | - dy = C1 + | (-P(x) + Q(x)) dx | y | | / / Examples ======== >>> from sympy import Function, dsolve, Eq, pprint, log >>> from sympy.abc import x >>> f = Function('f') >>> pprint(dsolve(Eq(x*f(x).diff(x) + f(x), log(x)*f(x)**2), ... f(x), hint='Bernoulli')) 1 f(x) = ----------------- C1*x + log(x) + 1 References ========== - https://en.wikipedia.org/wiki/Bernoulli_differential_equation - M. Tenenbaum & H. Pollard, "Ordinary Differential Equations", Dover 1963, pp. 95 # indirect doctest """ hint = "Bernoulli" has_integral = True order = [1] def _wilds(self, f, x, order): P = Wild('P', exclude=[f(x)]) Q = Wild('Q', exclude=[f(x)]) n = Wild('n', exclude=[x, f(x), f(x).diff(x)]) return P, Q, n def _equation(self, fx, x, order): P, Q, n = self.wilds() return fx.diff(x) + P*fx - Q*fx**n def _get_general_solution(self, *, simplify_flag: bool = True): P, Q, n = self.wilds_match() fx = self.ode_problem.func x = self.ode_problem.sym (C1,) = self.ode_problem.get_numbered_constants(num=1) if n==1: gensol = Eq(log(fx), ( C1 + Integral((-P + Q),x) )) else: gensol = Eq(fx**(1-n), ( (C1 - (n - 1) * Integral(Q*exp(-n*Integral(P, x)) * exp(Integral(P, x)), x) ) * exp(-(1 - n)*Integral(P, x))) ) return [gensol] class Factorable(SingleODESolver): r""" Solves equations having a solvable factor. This function is used to solve the equation having factors. Factors may be of type algebraic or ode. It will try to solve each factor independently. Factors will be solved by calling dsolve. We will return the list of solutions. Examples ======== >>> from sympy import Function, dsolve, pprint >>> from sympy.abc import x >>> f = Function('f') >>> eq = (f(x)**2-4)*(f(x).diff(x)+f(x)) >>> pprint(dsolve(eq, f(x))) -x [f(x) = 2, f(x) = -2, f(x) = C1*e ] """ hint = "factorable" has_integral = False def _matches(self): eq = self.ode_problem.eq f = self.ode_problem.func.func x = self.ode_problem.sym order =self.ode_problem.order df = f(x).diff(x) self.eqs = [] eq = eq.collect(f(x), func = cancel) eq = fraction(factor(eq))[0] factors = Mul.make_args(factor(eq)) roots = [fac.as_base_exp() for fac in factors if len(fac.args)!=0] if len(roots)>1 or roots[0][1]>1: for base,expo in roots: if base.has(f(x)): self.eqs.append(base) if len(self.eqs)>0: return True roots = solve(eq, df) if len(roots)>0: self.eqs = [(df - root) for root in roots] if len(self.eqs)==1: if order>1: return False if self.eqs[0].has(Float): return False return fraction(factor(self.eqs[0]))[0]-eq!=0 return True return False def _get_general_solution(self, *, simplify_flag: bool = True): func = self.ode_problem.func.func x = self.ode_problem.sym eqns = self.eqs sols = [] for eq in eqns: try: sol = dsolve(eq, func(x)) except NotImplementedError: continue else: if isinstance(sol, list): sols.extend(sol) else: sols.append(sol) if sols == []: raise NotImplementedError("The given ODE " + str(eq) + " cannot be solved by" + " the factorable group method") return sols class RiccatiSpecial(SinglePatternODESolver): r""" The general Riccati equation has the form .. math:: dy/dx = f(x) y^2 + g(x) y + h(x)\text{.} While it does not have a general solution [1], the "special" form, `dy/dx = a y^2 - b x^c`, does have solutions in many cases [2]. This routine returns a solution for `a(dy/dx) = b y^2 + c y/x + d/x^2` that is obtained by using a suitable change of variables to reduce it to the special form and is valid when neither `a` nor `b` are zero and either `c` or `d` is zero. >>> from sympy.abc import x, a, b, c, d >>> from sympy.solvers.ode import dsolve, checkodesol >>> from sympy import pprint, Function >>> f = Function('f') >>> y = f(x) >>> genform = a*y.diff(x) - (b*y**2 + c*y/x + d/x**2) >>> sol = dsolve(genform, y) >>> pprint(sol, wrap_line=False) / / __________________ \\ | __________________ | / 2 || | / 2 | \/ 4*b*d - (a + c) *log(x)|| -|a + c - \/ 4*b*d - (a + c) *tan|C1 + ----------------------------|| \ \ 2*a // f(x) = ------------------------------------------------------------------------ 2*b*x >>> checkodesol(genform, sol, order=1)[0] True References ========== 1. http://www.maplesoft.com/support/help/Maple/view.aspx?path=odeadvisor/Riccati 2. http://eqworld.ipmnet.ru/en/solutions/ode/ode0106.pdf - http://eqworld.ipmnet.ru/en/solutions/ode/ode0123.pdf """ hint = "Riccati_special_minus2" has_integral = False order = [1] def _wilds(self, f, x, order): a = Wild('a', exclude=[x, f(x), f(x).diff(x), 0]) b = Wild('b', exclude=[x, f(x), f(x).diff(x), 0]) c = Wild('c', exclude=[x, f(x), f(x).diff(x)]) d = Wild('d', exclude=[x, f(x), f(x).diff(x)]) return a, b, c, d def _equation(self, fx, x, order): a, b, c, d = self.wilds() return a*fx.diff(x) + b*fx**2 + c*fx/x + d/x**2 def _get_general_solution(self, *, simplify_flag: bool = True): a, b, c, d = self.wilds_match() fx = self.ode_problem.func x = self.ode_problem.sym (C1,) = self.ode_problem.get_numbered_constants(num=1) mu = sqrt(4*d*b - (a - c)**2) gensol = Eq(fx, (a - c - mu*tan(mu/(2*a)*log(x) + C1))/(2*b*x)) return [gensol] class SecondNonlinearAutonomousConserved(SinglePatternODESolver): r""" Gives solution for the autonomous second order nonlinear differential equation of the form .. math :: f''(x) = g(f(x)) The solution for this differential equation can be computed by multiplying by `f'(x)` and integrating on both sides, converting it into a first order differential equation. Examples ======== >>> from sympy import Function, symbols, dsolve >>> f, g = symbols('f g', cls=Function) >>> x = symbols('x') >>> eq = f(x).diff(x, 2) - g(f(x)) >>> dsolve(eq, simplify=False) [Eq(Integral(1/sqrt(C1 + 2*Integral(g(_u), _u)), (_u, f(x))), C2 + x), Eq(Integral(1/sqrt(C1 + 2*Integral(g(_u), _u)), (_u, f(x))), C2 - x)] >>> from sympy import exp, log >>> eq = f(x).diff(x, 2) - exp(f(x)) + log(f(x)) >>> dsolve(eq, simplify=False) [Eq(Integral(1/sqrt(-2*_u*log(_u) + 2*_u + C1 + 2*exp(_u)), (_u, f(x))), C2 + x), Eq(Integral(1/sqrt(-2*_u*log(_u) + 2*_u + C1 + 2*exp(_u)), (_u, f(x))), C2 - x)] References ========== http://eqworld.ipmnet.ru/en/solutions/ode/ode0301.pdf """ hint = "2nd_nonlinear_autonomous_conserved" has_integral = True order = [2] def _wilds(self, f, x, order): fy = Wild('fy', exclude=[0, f(x).diff(x), f(x).diff(x, 2)]) return (fy,) def _equation(self, fx, x, order): fy = self.wilds()[0] return fx.diff(x, 2) + fy def _verify(self, fx): return self.ode_problem.is_autonomous def _get_general_solution(self, *, simplify_flag: bool = True): g = self.wilds_match()[0] fx = self.ode_problem.func x = self.ode_problem.sym u = Dummy('u') g = g.subs(fx, u) C1, C2 = self.ode_problem.get_numbered_constants(num=2) inside = -2*Integral(g, u) + C1 lhs = Integral(1/sqrt(inside), (u, fx)) return [Eq(lhs, C2 + x), Eq(lhs, C2 - x)] class Liouville(SinglePatternODESolver): r""" Solves 2nd order Liouville differential equations. The general form of a Liouville ODE is .. math:: \frac{d^2 y}{dx^2} + g(y) \left(\! \frac{dy}{dx}\!\right)^2 + h(x) \frac{dy}{dx}\text{.} The general solution is: >>> from sympy import Function, dsolve, Eq, pprint, diff >>> from sympy.abc import x >>> f, g, h = map(Function, ['f', 'g', 'h']) >>> genform = Eq(diff(f(x),x,x) + g(f(x))*diff(f(x),x)**2 + ... h(x)*diff(f(x),x), 0) >>> pprint(genform) 2 2 /d \ d d g(f(x))*|--(f(x))| + h(x)*--(f(x)) + ---(f(x)) = 0 \dx / dx 2 dx >>> pprint(dsolve(genform, f(x), hint='Liouville_Integral')) f(x) / / | | | / | / | | | | | - | h(x) dx | | g(y) dy | | | | | / | / C1 + C2* | e dx + | e dy = 0 | | / / Examples ======== >>> from sympy import Function, dsolve, Eq, pprint >>> from sympy.abc import x >>> f = Function('f') >>> pprint(dsolve(diff(f(x), x, x) + diff(f(x), x)**2/f(x) + ... diff(f(x), x)/x, f(x), hint='Liouville')) ________________ ________________ [f(x) = -\/ C1 + C2*log(x) , f(x) = \/ C1 + C2*log(x) ] References ========== - Goldstein and Braun, "Advanced Methods for the Solution of Differential Equations", pp. 98 - http://www.maplesoft.com/support/help/Maple/view.aspx?path=odeadvisor/Liouville # indirect doctest """ hint = "Liouville" has_integral = True order = [2] def _wilds(self, f, x, order): d = Wild('d', exclude=[f(x).diff(x), f(x).diff(x, 2)]) e = Wild('e', exclude=[f(x).diff(x)]) k = Wild('k', exclude=[f(x).diff(x)]) return d, e, k def _equation(self, fx, x, order): # Liouville ODE in the form # f(x).diff(x, 2) + g(f(x))*(f(x).diff(x))**2 + h(x)*f(x).diff(x) # See Goldstein and Braun, "Advanced Methods for the Solution of # Differential Equations", pg. 98 d, e, k = self.wilds() return d*fx.diff(x, 2) + e*fx.diff(x)**2 + k*fx.diff(x) def _verify(self, fx): d, e, k = self.wilds_match() self.y = Dummy('y') x = self.ode_problem.sym self.g = simplify(e/d).subs(fx, self.y) self.h = simplify(k/d).subs(fx, self.y) if self.y in self.h.free_symbols or x in self.g.free_symbols: return False return True def _get_general_solution(self, *, simplify_flag: bool = True): d, e, k = self.wilds_match() fx = self.ode_problem.func x = self.ode_problem.sym C1, C2 = self.ode_problem.get_numbered_constants(num=2) int = Integral(exp(Integral(self.g, self.y)), (self.y, None, fx)) gen_sol = Eq(int + C1*Integral(exp(-Integral(self.h, x)), x) + C2, 0) return [gen_sol] class Separable(SinglePatternODESolver): r""" Solves separable 1st order differential equations. This is any differential equation that can be written as `P(y) \tfrac{dy}{dx} = Q(x)`. The solution can then just be found by rearranging terms and integrating: `\int P(y) \,dy = \int Q(x) \,dx`. This hint uses :py:meth:`sympy.simplify.simplify.separatevars` as its back end, so if a separable equation is not caught by this solver, it is most likely the fault of that function. :py:meth:`~sympy.simplify.simplify.separatevars` is smart enough to do most expansion and factoring necessary to convert a separable equation `F(x, y)` into the proper form `P(x)\cdot{}Q(y)`. The general solution is:: >>> from sympy import Function, dsolve, Eq, pprint >>> from sympy.abc import x >>> a, b, c, d, f = map(Function, ['a', 'b', 'c', 'd', 'f']) >>> genform = Eq(a(x)*b(f(x))*f(x).diff(x), c(x)*d(f(x))) >>> pprint(genform) d a(x)*b(f(x))*--(f(x)) = c(x)*d(f(x)) dx >>> pprint(dsolve(genform, f(x), hint='separable_Integral')) f(x) / / | | | b(y) | c(x) | ---- dy = C1 + | ---- dx | d(y) | a(x) | | / / Examples ======== >>> from sympy import Function, dsolve, Eq >>> from sympy.abc import x >>> f = Function('f') >>> pprint(dsolve(Eq(f(x)*f(x).diff(x) + x, 3*x*f(x)**2), f(x), ... hint='separable', simplify=False)) / 2 \ 2 log\3*f (x) - 1/ x ---------------- = C1 + -- 6 2 References ========== - M. Tenenbaum & H. Pollard, "Ordinary Differential Equations", Dover 1963, pp. 52 # indirect doctest """ hint = "separable" has_integral = True order = [1] def _wilds(self, f, x, order): d = Wild('d', exclude=[f(x).diff(x), f(x).diff(x, 2)]) e = Wild('e', exclude=[f(x).diff(x)]) return d, e def _equation(self, fx, x, order): d, e = self.wilds() return d + e*fx.diff(x) def _verify(self, fx): d, e = self.wilds_match() self.y = Dummy('y') x = self.ode_problem.sym d = separatevars(d.subs(fx, self.y)) e = separatevars(e.subs(fx, self.y)) # m1[coeff]*m1[x]*m1[y] + m2[coeff]*m2[x]*m2[y]*y' self.m1 = separatevars(d, dict=True, symbols=(x, self.y)) self.m2 = separatevars(e, dict=True, symbols=(x, self.y)) if self.m1 and self.m2: return True return False def _get_match_object(self): fx = self.ode_problem.func x = self.ode_problem.sym return self.m1, self.m2, x, fx def _get_general_solution(self, *, simplify_flag: bool = True): m1, m2, x, fx = self._get_match_object() (C1, ) = self.ode_problem.get_numbered_constants(num=1) int = Integral(m2['coeff']*m2[self.y]/m1[self.y], (self.y, None, fx)) gen_sol = Eq(int, Integral(-m1['coeff']*m1[x]/ m2[x], x) + C1) return [gen_sol] class SeparableReduced(Separable): r""" Solves a differential equation that can be reduced to the separable form. The general form of this equation is .. math:: y' + (y/x) H(x^n y) = 0\text{}. This can be solved by substituting `u(y) = x^n y`. The equation then reduces to the separable form `\frac{u'}{u (\mathrm{power} - H(u))} - \frac{1}{x} = 0`. The general solution is: >>> from sympy import Function, dsolve, pprint >>> from sympy.abc import x, n >>> f, g = map(Function, ['f', 'g']) >>> genform = f(x).diff(x) + (f(x)/x)*g(x**n*f(x)) >>> pprint(genform) / n \ d f(x)*g\x *f(x)/ --(f(x)) + --------------- dx x >>> pprint(dsolve(genform, hint='separable_reduced')) n x *f(x) / | | 1 | ------------ dy = C1 + log(x) | y*(n - g(y)) | / See Also ======== :obj:`sympy.solvers.ode.single.Separable` Examples ======== >>> from sympy import Function, pprint >>> from sympy.solvers.ode.ode import dsolve >>> from sympy.abc import x >>> f = Function('f') >>> d = f(x).diff(x) >>> eq = (x - x**2*f(x))*d - f(x) >>> dsolve(eq, hint='separable_reduced') [Eq(f(x), (1 - sqrt(C1*x**2 + 1))/x), Eq(f(x), (sqrt(C1*x**2 + 1) + 1)/x)] >>> pprint(dsolve(eq, hint='separable_reduced')) ___________ ___________ / 2 / 2 1 - \/ C1*x + 1 \/ C1*x + 1 + 1 [f(x) = ------------------, f(x) = ------------------] x x References ========== - Joel Moses, "Symbolic Integration - The Stormy Decade", Communications of the ACM, Volume 14, Number 8, August 1971, pp. 558 """ hint = "separable_reduced" has_integral = True order = [1] def _degree(self, expr, x): # Made this function to calculate the degree of # x in an expression. If expr will be of form # x**p*y, (wheare p can be variables/rationals) then it # will return p. for val in expr: if val.has(x): if isinstance(val, Pow) and val.as_base_exp()[0] == x: return (val.as_base_exp()[1]) elif val == x: return (val.as_base_exp()[1]) else: return self._degree(val.args, x) return 0 def _powers(self, expr): # this function will return all the different relative power of x w.r.t f(x). # expr = x**p * f(x)**q then it will return {p/q}. pows = set() fx = self.ode_problem.func x = self.ode_problem.sym self.y = Dummy('y') if isinstance(expr, Add): exprs = expr.atoms(Add) elif isinstance(expr, Mul): exprs = expr.atoms(Mul) elif isinstance(expr, Pow): exprs = expr.atoms(Pow) else: exprs = {expr} for arg in exprs: if arg.has(x): _, u = arg.as_independent(x, fx) pow = self._degree((u.subs(fx, self.y), ), x)/self._degree((u.subs(fx, self.y), ), self.y) pows.add(pow) return pows def _verify(self, fx): num, den = self.wilds_match() x = self.ode_problem.sym factor = simplify(x/fx*num/den) # Try representing factor in terms of x^n*y # where n is lowest power of x in factor; # first remove terms like sqrt(2)*3 from factor.atoms(Mul) num, dem = factor.as_numer_denom() num = expand(num) dem = expand(dem) pows = self._powers(num) pows.update(self._powers(dem)) pows = list(pows) if(len(pows)==1) and pows[0]!=zoo: self.t = Dummy('t') self.r2 = {'t': self.t} num = num.subs(x**pows[0]*fx, self.t) dem = dem.subs(x**pows[0]*fx, self.t) test = num/dem free = test.free_symbols if len(free) == 1 and free.pop() == self.t: self.r2.update({'power' : pows[0], 'u' : test}) return True return False return False def _get_match_object(self): fx = self.ode_problem.func x = self.ode_problem.sym u = self.r2['u'].subs(self.r2['t'], self.y) ycoeff = 1/(self.y*(self.r2['power'] - u)) m1 = {self.y: 1, x: -1/x, 'coeff': 1} m2 = {self.y: ycoeff, x: 1, 'coeff': 1} return m1, m2, x, x**self.r2['power']*fx class HomogeneousCoeffSubsDepDivIndep(SinglePatternODESolver): r""" Solves a 1st order differential equation with homogeneous coefficients using the substitution `u_1 = \frac{\text{<dependent variable>}}{\text{<independent variable>}}`. This is a differential equation .. math:: P(x, y) + Q(x, y) dy/dx = 0 such that `P` and `Q` are homogeneous and of the same order. A function `F(x, y)` is homogeneous of order `n` if `F(x t, y t) = t^n F(x, y)`. Equivalently, `F(x, y)` can be rewritten as `G(y/x)` or `H(x/y)`. See also the docstring of :py:meth:`~sympy.solvers.ode.homogeneous_order`. If the coefficients `P` and `Q` in the differential equation above are homogeneous functions of the same order, then it can be shown that the substitution `y = u_1 x` (i.e. `u_1 = y/x`) will turn the differential equation into an equation separable in the variables `x` and `u`. If `h(u_1)` is the function that results from making the substitution `u_1 = f(x)/x` on `P(x, f(x))` and `g(u_2)` is the function that results from the substitution on `Q(x, f(x))` in the differential equation `P(x, f(x)) + Q(x, f(x)) f'(x) = 0`, then the general solution is:: >>> from sympy import Function, dsolve, pprint >>> from sympy.abc import x >>> f, g, h = map(Function, ['f', 'g', 'h']) >>> genform = g(f(x)/x) + h(f(x)/x)*f(x).diff(x) >>> pprint(genform) /f(x)\ /f(x)\ d g|----| + h|----|*--(f(x)) \ x / \ x / dx >>> pprint(dsolve(genform, f(x), ... hint='1st_homogeneous_coeff_subs_dep_div_indep_Integral')) f(x) ---- x / | | -h(u1) log(x) = C1 + | ---------------- d(u1) | u1*h(u1) + g(u1) | / Where `u_1 h(u_1) + g(u_1) \ne 0` and `x \ne 0`. See also the docstrings of :obj:`~sympy.solvers.ode.single.HomogeneousCoeffBest` and :obj:`~sympy.solvers.ode.single.HomogeneousCoeffSubsIndepDivDep`. Examples ======== >>> from sympy import Function, dsolve >>> from sympy.abc import x >>> f = Function('f') >>> pprint(dsolve(2*x*f(x) + (x**2 + f(x)**2)*f(x).diff(x), f(x), ... hint='1st_homogeneous_coeff_subs_dep_div_indep', simplify=False)) / 3 \ |3*f(x) f (x)| log|------ + -----| | x 3 | \ x / log(x) = log(C1) - ------------------- 3 References ========== - https://en.wikipedia.org/wiki/Homogeneous_differential_equation - M. Tenenbaum & H. Pollard, "Ordinary Differential Equations", Dover 1963, pp. 59 # indirect doctest """ hint = "1st_homogeneous_coeff_subs_dep_div_indep" has_integral = True order = [1] def _wilds(self, f, x, order): d = Wild('d', exclude=[f(x).diff(x), f(x).diff(x, 2)]) e = Wild('e', exclude=[f(x).diff(x)]) return d, e def _equation(self, fx, x, order): d, e = self.wilds() return d + e*fx.diff(x) def _verify(self, fx): self.d, self.e = self.wilds_match() self.y = Dummy('y') x = self.ode_problem.sym self.d = separatevars(self.d.subs(fx, self.y)) self.e = separatevars(self.e.subs(fx, self.y)) ordera = homogeneous_order(self.d, x, self.y) orderb = homogeneous_order(self.e, x, self.y) if ordera == orderb and ordera is not None: self.u = Dummy('u') if simplify((self.d + self.u*self.e).subs({x: 1, self.y: self.u})) != 0: return True return False return False def _get_match_object(self): fx = self.ode_problem.func x = self.ode_problem.sym self.u1 = Dummy('u1') xarg = 0 yarg = 0 return [self.d, self.e, fx, x, self.u, self.u1, self.y, xarg, yarg] def _get_general_solution(self, *, simplify_flag: bool = True): d, e, fx, x, u, u1, y, xarg, yarg = self._get_match_object() (C1, ) = self.ode_problem.get_numbered_constants(num=1) int = Integral( (-e/(d + u1*e)).subs({x: 1, y: u1}), (u1, None, fx/x)) sol = logcombine(Eq(log(x), int + log(C1)), force=True) gen_sol = sol.subs(fx, u).subs(((u, u - yarg), (x, x - xarg), (u, fx))) return [gen_sol] class HomogeneousCoeffSubsIndepDivDep(SinglePatternODESolver): r""" Solves a 1st order differential equation with homogeneous coefficients using the substitution `u_2 = \frac{\text{<independent variable>}}{\text{<dependent variable>}}`. This is a differential equation .. math:: P(x, y) + Q(x, y) dy/dx = 0 such that `P` and `Q` are homogeneous and of the same order. A function `F(x, y)` is homogeneous of order `n` if `F(x t, y t) = t^n F(x, y)`. Equivalently, `F(x, y)` can be rewritten as `G(y/x)` or `H(x/y)`. See also the docstring of :py:meth:`~sympy.solvers.ode.homogeneous_order`. If the coefficients `P` and `Q` in the differential equation above are homogeneous functions of the same order, then it can be shown that the substitution `x = u_2 y` (i.e. `u_2 = x/y`) will turn the differential equation into an equation separable in the variables `y` and `u_2`. If `h(u_2)` is the function that results from making the substitution `u_2 = x/f(x)` on `P(x, f(x))` and `g(u_2)` is the function that results from the substitution on `Q(x, f(x))` in the differential equation `P(x, f(x)) + Q(x, f(x)) f'(x) = 0`, then the general solution is: >>> from sympy import Function, dsolve, pprint >>> from sympy.abc import x >>> f, g, h = map(Function, ['f', 'g', 'h']) >>> genform = g(x/f(x)) + h(x/f(x))*f(x).diff(x) >>> pprint(genform) / x \ / x \ d g|----| + h|----|*--(f(x)) \f(x)/ \f(x)/ dx >>> pprint(dsolve(genform, f(x), ... hint='1st_homogeneous_coeff_subs_indep_div_dep_Integral')) x ---- f(x) / | | -g(u1) | ---------------- d(u1) | u1*g(u1) + h(u1) | / <BLANKLINE> f(x) = C1*e Where `u_1 g(u_1) + h(u_1) \ne 0` and `f(x) \ne 0`. See also the docstrings of :obj:`~sympy.solvers.ode.single.HomogeneousCoeffBest` and :obj:`~sympy.solvers.ode.single.HomogeneousCoeffSubsDepDivIndep`. Examples ======== >>> from sympy import Function, pprint, dsolve >>> from sympy.abc import x >>> f = Function('f') >>> pprint(dsolve(2*x*f(x) + (x**2 + f(x)**2)*f(x).diff(x), f(x), ... hint='1st_homogeneous_coeff_subs_indep_div_dep', ... simplify=False)) / 2 \ | 3*x | log|----- + 1| | 2 | \f (x) / log(f(x)) = log(C1) - -------------- 3 References ========== - https://en.wikipedia.org/wiki/Homogeneous_differential_equation - M. Tenenbaum & H. Pollard, "Ordinary Differential Equations", Dover 1963, pp. 59 # indirect doctest """ hint = "1st_homogeneous_coeff_subs_indep_div_dep" has_integral = True order = [1] def _wilds(self, f, x, order): d = Wild('d', exclude=[f(x).diff(x), f(x).diff(x, 2)]) e = Wild('e', exclude=[f(x).diff(x)]) return d, e def _equation(self, fx, x, order): d, e = self.wilds() return d + e*fx.diff(x) def _verify(self, fx): self.d, self.e = self.wilds_match() self.y = Dummy('y') x = self.ode_problem.sym self.d = separatevars(self.d.subs(fx, self.y)) self.e = separatevars(self.e.subs(fx, self.y)) ordera = homogeneous_order(self.d, x, self.y) orderb = homogeneous_order(self.e, x, self.y) if ordera == orderb and ordera is not None: self.u = Dummy('u') if simplify((self.e + self.u*self.d).subs({x: self.u, self.y: 1})) != 0: return True return False return False def _get_match_object(self): fx = self.ode_problem.func x = self.ode_problem.sym self.u1 = Dummy('u1') xarg = 0 yarg = 0 return [self.d, self.e, fx, x, self.u, self.u1, self.y, xarg, yarg] def _get_general_solution(self, *, simplify_flag: bool = True): d, e, fx, x, u, u1, y, xarg, yarg = self._get_match_object() (C1, ) = self.ode_problem.get_numbered_constants(num=1) int = Integral(simplify((-d/(e + u1*d)).subs({x: u1, y: 1})),(u1, None, x/fx)) sol = logcombine(Eq(log(fx), int + log(C1)), force=True) gen_sol = sol.subs(fx, u).subs(((u, u - yarg), (x, x - xarg), (u, fx))) return [gen_sol] class HomogeneousCoeffBest(HomogeneousCoeffSubsIndepDivDep, HomogeneousCoeffSubsDepDivIndep): r""" Returns the best solution to an ODE from the two hints ``1st_homogeneous_coeff_subs_dep_div_indep`` and ``1st_homogeneous_coeff_subs_indep_div_dep``. This is as determined by :py:meth:`~sympy.solvers.ode.ode.ode_sol_simplicity`. See the :obj:`~sympy.solvers.ode.single.HomogeneousCoeffSubsIndepDivDep` and :obj:`~sympy.solvers.ode.single.HomogeneousCoeffSubsDepDivIndep` docstrings for more information on these hints. Note that there is no ``ode_1st_homogeneous_coeff_best_Integral`` hint. Examples ======== >>> from sympy import Function, dsolve, pprint >>> from sympy.abc import x >>> f = Function('f') >>> pprint(dsolve(2*x*f(x) + (x**2 + f(x)**2)*f(x).diff(x), f(x), ... hint='1st_homogeneous_coeff_best', simplify=False)) / 2 \ | 3*x | log|----- + 1| | 2 | \f (x) / log(f(x)) = log(C1) - -------------- 3 References ========== - https://en.wikipedia.org/wiki/Homogeneous_differential_equation - M. Tenenbaum & H. Pollard, "Ordinary Differential Equations", Dover 1963, pp. 59 # indirect doctest """ hint = "1st_homogeneous_coeff_best" has_integral = False order = [1] def _verify(self, fx): if HomogeneousCoeffSubsIndepDivDep._verify(self, fx) and HomogeneousCoeffSubsDepDivIndep._verify(self, fx): return True return False def _get_general_solution(self, *, simplify_flag: bool = True): # There are two substitutions that solve the equation, u1=y/x and u2=x/y # # They produce different integrals, so try them both and see which # # one is easier sol1 = HomogeneousCoeffSubsIndepDivDep._get_general_solution(self) sol2 = HomogeneousCoeffSubsDepDivIndep._get_general_solution(self) fx = self.ode_problem.func if simplify_flag: sol1 = odesimp(self.ode_problem.eq, *sol1, fx, "1st_homogeneous_coeff_subs_indep_div_dep") sol2 = odesimp(self.ode_problem.eq, *sol2, fx, "1st_homogeneous_coeff_subs_dep_div_indep") return min([sol1, sol2], key=lambda x: ode_sol_simplicity(x, fx, trysolving=not simplify)) class LinearCoefficients(HomogeneousCoeffBest): r""" Solves a differential equation with linear coefficients. The general form of a differential equation with linear coefficients is .. math:: y' + F\left(\!\frac{a_1 x + b_1 y + c_1}{a_2 x + b_2 y + c_2}\!\right) = 0\text{,} where `a_1`, `b_1`, `c_1`, `a_2`, `b_2`, `c_2` are constants and `a_1 b_2 - a_2 b_1 \ne 0`. This can be solved by substituting: .. math:: x = x' + \frac{b_2 c_1 - b_1 c_2}{a_2 b_1 - a_1 b_2} y = y' + \frac{a_1 c_2 - a_2 c_1}{a_2 b_1 - a_1 b_2}\text{.} This substitution reduces the equation to a homogeneous differential equation. See Also ======== :obj:`sympy.solvers.ode.single.HomogeneousCoeffBest` :obj:`sympy.solvers.ode.single.HomogeneousCoeffSubsIndepDivDep` :obj:`sympy.solvers.ode.single.HomogeneousCoeffSubsDepDivIndep` Examples ======== >>> from sympy import Function, pprint >>> from sympy.solvers.ode.ode import dsolve >>> from sympy.abc import x >>> f = Function('f') >>> df = f(x).diff(x) >>> eq = (x + f(x) + 1)*df + (f(x) - 6*x + 1) >>> dsolve(eq, hint='linear_coefficients') [Eq(f(x), -x - sqrt(C1 + 7*x**2) - 1), Eq(f(x), -x + sqrt(C1 + 7*x**2) - 1)] >>> pprint(dsolve(eq, hint='linear_coefficients')) ___________ ___________ / 2 / 2 [f(x) = -x - \/ C1 + 7*x - 1, f(x) = -x + \/ C1 + 7*x - 1] References ========== - Joel Moses, "Symbolic Integration - The Stormy Decade", Communications of the ACM, Volume 14, Number 8, August 1971, pp. 558 """ hint = "linear_coefficients" has_integral = True order = [1] def _wilds(self, f, x, order): d = Wild('d', exclude=[f(x).diff(x), f(x).diff(x, 2)]) e = Wild('e', exclude=[f(x).diff(x)]) return d, e def _equation(self, fx, x, order): d, e = self.wilds() return d + e*fx.diff(x) def _verify(self, fx): self.d, self.e = self.wilds_match() a, b = self.wilds() F = self.d/self.e x = self.ode_problem.sym params = self._linear_coeff_match(F, fx) if params: self.xarg, self.yarg = params u = Dummy('u') t = Dummy('t') self.y = Dummy('y') # Dummy substitution for df and f(x). dummy_eq = self.ode_problem.eq.subs(((fx.diff(x), t), (fx, u))) reps = ((x, x + self.xarg), (u, u + self.yarg), (t, fx.diff(x)), (u, fx)) dummy_eq = simplify(dummy_eq.subs(reps)) # get the re-cast values for e and d r2 = collect(expand(dummy_eq), [fx.diff(x), fx]).match(a*fx.diff(x) + b) if r2: self.d, self.e = r2[b], r2[a] orderd = homogeneous_order(self.d, x, fx) ordere = homogeneous_order(self.e, x, fx) if orderd == ordere and orderd is not None: self.d = self.d.subs(fx, self.y) self.e = self.e.subs(fx, self.y) return True return False return False def _linear_coeff_match(self,expr, func): r""" Helper function to match hint ``linear_coefficients``. Matches the expression to the form `(a_1 x + b_1 f(x) + c_1)/(a_2 x + b_2 f(x) + c_2)` where the following conditions hold: 1. `a_1`, `b_1`, `c_1`, `a_2`, `b_2`, `c_2` are Rationals; 2. `c_1` or `c_2` are not equal to zero; 3. `a_2 b_1 - a_1 b_2` is not equal to zero. Return ``xarg``, ``yarg`` where 1. ``xarg`` = `(b_2 c_1 - b_1 c_2)/(a_2 b_1 - a_1 b_2)` 2. ``yarg`` = `(a_1 c_2 - a_2 c_1)/(a_2 b_1 - a_1 b_2)` Examples ======== >>> from sympy import Function >>> from sympy.abc import x >>> from sympy.solvers.ode.single import LinearCoefficients >>> from sympy.functions.elementary.trigonometric import sin >>> f = Function('f') >>> eq = (-25*f(x) - 8*x + 62)/(4*f(x) + 11*x - 11) >>> obj = LinearCoefficients(eq) >>> obj._linear_coeff_match(eq, f(x)) (1/9, 22/9) >>> eq = sin((-5*f(x) - 8*x + 6)/(4*f(x) + x - 1)) >>> obj = LinearCoefficients(eq) >>> obj._linear_coeff_match(eq, f(x)) (19/27, 2/27) >>> eq = sin(f(x)/x) >>> obj = LinearCoefficients(eq) >>> obj._linear_coeff_match(eq, f(x)) """ f = func.func x = func.args[0] def abc(eq): r''' Internal function of _linear_coeff_match that returns Rationals a, b, c if eq is a*x + b*f(x) + c, else None. ''' eq = _mexpand(eq) c = eq.as_independent(x, f(x), as_Add=True)[0] if not c.is_Rational: return a = eq.coeff(x) if not a.is_Rational: return b = eq.coeff(f(x)) if not b.is_Rational: return if eq == a*x + b*f(x) + c: return a, b, c def match(arg): r''' Internal function of _linear_coeff_match that returns Rationals a1, b1, c1, a2, b2, c2 and a2*b1 - a1*b2 of the expression (a1*x + b1*f(x) + c1)/(a2*x + b2*f(x) + c2) if one of c1 or c2 and a2*b1 - a1*b2 is non-zero, else None. ''' n, d = arg.together().as_numer_denom() m = abc(n) if m is not None: a1, b1, c1 = m m = abc(d) if m is not None: a2, b2, c2 = m d = a2*b1 - a1*b2 if (c1 or c2) and d: return a1, b1, c1, a2, b2, c2, d m = [fi.args[0] for fi in expr.atoms(Function) if fi.func != f and len(fi.args) == 1 and not fi.args[0].is_Function] or {expr} m1 = match(m.pop()) if m1 and all(match(mi) == m1 for mi in m): a1, b1, c1, a2, b2, c2, denom = m1 return (b2*c1 - b1*c2)/denom, (a1*c2 - a2*c1)/denom def _get_match_object(self): fx = self.ode_problem.func x = self.ode_problem.sym self.u1 = Dummy('u1') u = Dummy('u') return [self.d, self.e, fx, x, u, self.u1, self.y, self.xarg, self.yarg] # Avoid circular import: from .ode import dsolve, ode_sol_simplicity, odesimp, homogeneous_order
daf095ab0d5396fc403ec262d8cc91a9ee3d5a67d77fdc739dbb9244562d9b3d
from sympy.core.containers import Tuple from sympy.core.compatibility import ordered from sympy.core.function import (Function, Lambda, nfloat, diff) from sympy.core.mod import Mod from sympy.core.numbers import (E, I, Rational, oo, pi) from sympy.core.relational import (Eq, Gt, Ne) from sympy.core.singleton import S from sympy.core.symbol import (Dummy, Symbol, symbols) from sympy.functions.elementary.complexes import (Abs, arg, im, re, sign) from sympy.functions.elementary.exponential import (LambertW, exp, log) from sympy.functions.elementary.hyperbolic import (HyperbolicFunction, sinh, tanh, cosh, sech, coth) from sympy.functions.elementary.miscellaneous import sqrt, Min, Max from sympy.functions.elementary.piecewise import Piecewise from sympy.functions.elementary.trigonometric import ( TrigonometricFunction, acos, acot, acsc, asec, asin, atan, atan2, cos, cot, csc, sec, sin, tan) from sympy.functions.special.error_functions import (erf, erfc, erfcinv, erfinv) from sympy.logic.boolalg import And from sympy.matrices.dense import MutableDenseMatrix as Matrix from sympy.matrices.immutable import ImmutableDenseMatrix from sympy.polys.polytools import Poly from sympy.polys.rootoftools import CRootOf from sympy.sets.contains import Contains from sympy.sets.conditionset import ConditionSet from sympy.sets.fancysets import ImageSet, Range from sympy.sets.sets import (Complement, EmptySet, FiniteSet, Intersection, Interval, Union, imageset, ProductSet) from sympy.simplify import simplify from sympy.tensor.indexed import Indexed from sympy.utilities.iterables import numbered_symbols from sympy.testing.pytest import (XFAIL, raises, skip, slow, SKIP, _both_exp_pow) from sympy.testing.randtest import verify_numerically as tn from sympy.physics.units import cm from sympy.solvers import solve from sympy.solvers.solveset import ( solveset_real, domain_check, solveset_complex, linear_eq_to_matrix, linsolve, _is_function_class_equation, invert_real, invert_complex, solveset, solve_decomposition, substitution, nonlinsolve, solvify, _is_finite_with_finite_vars, _transolve, _is_exponential, _solve_exponential, _is_logarithmic, _is_lambert, _solve_logarithm, _term_factors, _is_modular, NonlinearError) from sympy.abc import (a, b, c, d, e, f, g, h, i, j, k, l, m, n, q, r, t, w, x, y, z) def dumeq(i, j): if type(i) in (list, tuple): return all(dumeq(i, j) for i, j in zip(i, j)) return i == j or i.dummy_eq(j) @_both_exp_pow def test_invert_real(): x = Symbol('x', real=True) def ireal(x, s=S.Reals): return Intersection(s, x) # issue 14223 assert invert_real(x, 0, x, Interval(1, 2)) == (x, S.EmptySet) assert invert_real(exp(x), z, x) == (x, ireal(FiniteSet(log(z)))) y = Symbol('y', positive=True) n = Symbol('n', real=True) assert invert_real(x + 3, y, x) == (x, FiniteSet(y - 3)) assert invert_real(x*3, y, x) == (x, FiniteSet(y / 3)) assert invert_real(exp(x), y, x) == (x, FiniteSet(log(y))) assert invert_real(exp(3*x), y, x) == (x, FiniteSet(log(y) / 3)) assert invert_real(exp(x + 3), y, x) == (x, FiniteSet(log(y) - 3)) assert invert_real(exp(x) + 3, y, x) == (x, ireal(FiniteSet(log(y - 3)))) assert invert_real(exp(x)*3, y, x) == (x, FiniteSet(log(y / 3))) assert invert_real(log(x), y, x) == (x, FiniteSet(exp(y))) assert invert_real(log(3*x), y, x) == (x, FiniteSet(exp(y) / 3)) assert invert_real(log(x + 3), y, x) == (x, FiniteSet(exp(y) - 3)) assert invert_real(Abs(x), y, x) == (x, FiniteSet(y, -y)) assert invert_real(2**x, y, x) == (x, FiniteSet(log(y)/log(2))) assert invert_real(2**exp(x), y, x) == (x, ireal(FiniteSet(log(log(y)/log(2))))) assert invert_real(x**2, y, x) == (x, FiniteSet(sqrt(y), -sqrt(y))) assert invert_real(x**S.Half, y, x) == (x, FiniteSet(y**2)) raises(ValueError, lambda: invert_real(x, x, x)) # issue 21236 assert invert_real(x**pi, y, x) == (x, FiniteSet(y**(1/pi))) assert invert_real(x**pi, -E, x) == (x, EmptySet()) assert invert_real(x**Rational(3/2), 1000, x) == (x, FiniteSet(100)) assert invert_real(x**1.0, 1, x) == (x**1.0, FiniteSet(1)) raises(ValueError, lambda: invert_real(S.One, y, x)) assert invert_real(x**31 + x, y, x) == (x**31 + x, FiniteSet(y)) lhs = x**31 + x base_values = FiniteSet(y - 1, -y - 1) assert invert_real(Abs(x**31 + x + 1), y, x) == (lhs, base_values) assert dumeq(invert_real(sin(x), y, x), (x, imageset(Lambda(n, n*pi + (-1)**n*asin(y)), S.Integers))) assert dumeq(invert_real(sin(exp(x)), y, x), (x, imageset(Lambda(n, log((-1)**n*asin(y) + n*pi)), S.Integers))) assert dumeq(invert_real(csc(x), y, x), (x, imageset(Lambda(n, n*pi + (-1)**n*acsc(y)), S.Integers))) assert dumeq(invert_real(csc(exp(x)), y, x), (x, imageset(Lambda(n, log((-1)**n*acsc(y) + n*pi)), S.Integers))) assert dumeq(invert_real(cos(x), y, x), (x, Union(imageset(Lambda(n, 2*n*pi + acos(y)), S.Integers), \ imageset(Lambda(n, 2*n*pi - acos(y)), S.Integers)))) assert dumeq(invert_real(cos(exp(x)), y, x), (x, Union(imageset(Lambda(n, log(2*n*pi + acos(y))), S.Integers), \ imageset(Lambda(n, log(2*n*pi - acos(y))), S.Integers)))) assert dumeq(invert_real(sec(x), y, x), (x, Union(imageset(Lambda(n, 2*n*pi + asec(y)), S.Integers), \ imageset(Lambda(n, 2*n*pi - asec(y)), S.Integers)))) assert dumeq(invert_real(sec(exp(x)), y, x), (x, Union(imageset(Lambda(n, log(2*n*pi + asec(y))), S.Integers), \ imageset(Lambda(n, log(2*n*pi - asec(y))), S.Integers)))) assert dumeq(invert_real(tan(x), y, x), (x, imageset(Lambda(n, n*pi + atan(y)), S.Integers))) assert dumeq(invert_real(tan(exp(x)), y, x), (x, imageset(Lambda(n, log(n*pi + atan(y))), S.Integers))) assert dumeq(invert_real(cot(x), y, x), (x, imageset(Lambda(n, n*pi + acot(y)), S.Integers))) assert dumeq(invert_real(cot(exp(x)), y, x), (x, imageset(Lambda(n, log(n*pi + acot(y))), S.Integers))) assert dumeq(invert_real(tan(tan(x)), y, x), (tan(x), imageset(Lambda(n, n*pi + atan(y)), S.Integers))) x = Symbol('x', positive=True) assert invert_real(x**pi, y, x) == (x, FiniteSet(y**(1/pi))) def test_invert_complex(): assert invert_complex(x + 3, y, x) == (x, FiniteSet(y - 3)) assert invert_complex(x*3, y, x) == (x, FiniteSet(y / 3)) assert invert_complex((x - 1)**3, 0, x) == (x, FiniteSet(1)) assert dumeq(invert_complex(exp(x), y, x), (x, imageset(Lambda(n, I*(2*pi*n + arg(y)) + log(Abs(y))), S.Integers))) assert invert_complex(log(x), y, x) == (x, FiniteSet(exp(y))) raises(ValueError, lambda: invert_real(1, y, x)) raises(ValueError, lambda: invert_complex(x, x, x)) raises(ValueError, lambda: invert_complex(x, x, 1)) # https://github.com/skirpichev/omg/issues/16 assert invert_complex(sinh(x), 0, x) != (x, FiniteSet(0)) def test_domain_check(): assert domain_check(1/(1 + (1/(x+1))**2), x, -1) is False assert domain_check(x**2, x, 0) is True assert domain_check(x, x, oo) is False assert domain_check(0, x, oo) is False def test_issue_11536(): assert solveset(0**x - 100, x, S.Reals) == S.EmptySet assert solveset(0**x - 1, x, S.Reals) == FiniteSet(0) def test_issue_17479(): from sympy.solvers.solveset import nonlinsolve f = (x**2 + y**2)**2 + (x**2 + z**2)**2 - 2*(2*x**2 + y**2 + z**2) fx = f.diff(x) fy = f.diff(y) fz = f.diff(z) sol = nonlinsolve([fx, fy, fz], [x, y, z]) assert len(sol) >= 4 and len(sol) <= 20 # nonlinsolve has been giving a varying number of solutions # (originally 18, then 20, now 19) due to various internal changes. # Unfortunately not all the solutions are actually valid and some are # redundant. Since the original issue was that an exception was raised, # this first test only checks that nonlinsolve returns a "plausible" # solution set. The next test checks the result for correctness. @XFAIL def test_issue_18449(): x, y, z = symbols("x, y, z") f = (x**2 + y**2)**2 + (x**2 + z**2)**2 - 2*(2*x**2 + y**2 + z**2) fx = diff(f, x) fy = diff(f, y) fz = diff(f, z) sol = nonlinsolve([fx, fy, fz], [x, y, z]) for (xs, ys, zs) in sol: d = {x: xs, y: ys, z: zs} assert tuple(_.subs(d).simplify() for _ in (fx, fy, fz)) == (0, 0, 0) # After simplification and removal of duplicate elements, there should # only be 4 parametric solutions left: # simplifiedsolutions = FiniteSet((sqrt(1 - z**2), z, z), # (-sqrt(1 - z**2), z, z), # (sqrt(1 - z**2), -z, z), # (-sqrt(1 - z**2), -z, z)) # TODO: Is the above solution set definitely complete? def test_issue_21047(): f = (2 - x)**2 + (sqrt(x - 1) - 1)**6 assert(solveset(f, x, S.Reals)) == FiniteSet(2) f = (sqrt(x)-1)**2 + (sqrt(x)+1)**2 -2*x**2 + sqrt(2) assert solveset(f, x, S.Reals) == FiniteSet( S.Half - sqrt(2*sqrt(2) + 5)/2, S.Half + sqrt(2*sqrt(2) + 5)/2) def test_is_function_class_equation(): from sympy.abc import x, a assert _is_function_class_equation(TrigonometricFunction, tan(x), x) is True assert _is_function_class_equation(TrigonometricFunction, tan(x) - 1, x) is True assert _is_function_class_equation(TrigonometricFunction, tan(x) + sin(x), x) is True assert _is_function_class_equation(TrigonometricFunction, tan(x) + sin(x) - a, x) is True assert _is_function_class_equation(TrigonometricFunction, sin(x)*tan(x) + sin(x), x) is True assert _is_function_class_equation(TrigonometricFunction, sin(x)*tan(x + a) + sin(x), x) is True assert _is_function_class_equation(TrigonometricFunction, sin(x)*tan(x*a) + sin(x), x) is True assert _is_function_class_equation(TrigonometricFunction, a*tan(x) - 1, x) is True assert _is_function_class_equation(TrigonometricFunction, tan(x)**2 + sin(x) - 1, x) is True assert _is_function_class_equation(TrigonometricFunction, tan(x) + x, x) is False assert _is_function_class_equation(TrigonometricFunction, tan(x**2), x) is False assert _is_function_class_equation(TrigonometricFunction, tan(x**2) + sin(x), x) is False assert _is_function_class_equation(TrigonometricFunction, tan(x)**sin(x), x) is False assert _is_function_class_equation(TrigonometricFunction, tan(sin(x)) + sin(x), x) is False assert _is_function_class_equation(HyperbolicFunction, tanh(x), x) is True assert _is_function_class_equation(HyperbolicFunction, tanh(x) - 1, x) is True assert _is_function_class_equation(HyperbolicFunction, tanh(x) + sinh(x), x) is True assert _is_function_class_equation(HyperbolicFunction, tanh(x) + sinh(x) - a, x) is True assert _is_function_class_equation(HyperbolicFunction, sinh(x)*tanh(x) + sinh(x), x) is True assert _is_function_class_equation(HyperbolicFunction, sinh(x)*tanh(x + a) + sinh(x), x) is True assert _is_function_class_equation(HyperbolicFunction, sinh(x)*tanh(x*a) + sinh(x), x) is True assert _is_function_class_equation(HyperbolicFunction, a*tanh(x) - 1, x) is True assert _is_function_class_equation(HyperbolicFunction, tanh(x)**2 + sinh(x) - 1, x) is True assert _is_function_class_equation(HyperbolicFunction, tanh(x) + x, x) is False assert _is_function_class_equation(HyperbolicFunction, tanh(x**2), x) is False assert _is_function_class_equation(HyperbolicFunction, tanh(x**2) + sinh(x), x) is False assert _is_function_class_equation(HyperbolicFunction, tanh(x)**sinh(x), x) is False assert _is_function_class_equation(HyperbolicFunction, tanh(sinh(x)) + sinh(x), x) is False def test_garbage_input(): raises(ValueError, lambda: solveset_real([y], y)) x = Symbol('x', real=True) assert solveset_real(x, 1) == S.EmptySet assert solveset_real(x - 1, 1) == FiniteSet(x) assert solveset_real(x, pi) == S.EmptySet assert solveset_real(x, x**2) == S.EmptySet raises(ValueError, lambda: solveset_complex([x], x)) assert solveset_complex(x, pi) == S.EmptySet raises(ValueError, lambda: solveset((x, y), x)) raises(ValueError, lambda: solveset(x + 1, S.Reals)) raises(ValueError, lambda: solveset(x + 1, x, 2)) def test_solve_mul(): assert solveset_real((a*x + b)*(exp(x) - 3), x) == \ Union({log(3)}, Intersection({-b/a}, S.Reals)) anz = Symbol('anz', nonzero=True) bb = Symbol('bb', real=True) assert solveset_real((anz*x + bb)*(exp(x) - 3), x) == \ FiniteSet(-bb/anz, log(3)) assert solveset_real((2*x + 8)*(8 + exp(x)), x) == FiniteSet(S(-4)) assert solveset_real(x/log(x), x) == EmptySet() def test_solve_invert(): assert solveset_real(exp(x) - 3, x) == FiniteSet(log(3)) assert solveset_real(log(x) - 3, x) == FiniteSet(exp(3)) assert solveset_real(3**(x + 2), x) == FiniteSet() assert solveset_real(3**(2 - x), x) == FiniteSet() assert solveset_real(y - b*exp(a/x), x) == Intersection( S.Reals, FiniteSet(a/log(y/b))) # issue 4504 assert solveset_real(2**x - 10, x) == FiniteSet(1 + log(5)/log(2)) def test_errorinverses(): assert solveset_real(erf(x) - S.Half, x) == \ FiniteSet(erfinv(S.Half)) assert solveset_real(erfinv(x) - 2, x) == \ FiniteSet(erf(2)) assert solveset_real(erfc(x) - S.One, x) == \ FiniteSet(erfcinv(S.One)) assert solveset_real(erfcinv(x) - 2, x) == FiniteSet(erfc(2)) def test_solve_polynomial(): x = Symbol('x', real=True) y = Symbol('y', real=True) assert solveset_real(3*x - 2, x) == FiniteSet(Rational(2, 3)) assert solveset_real(x**2 - 1, x) == FiniteSet(-S.One, S.One) assert solveset_real(x - y**3, x) == FiniteSet(y ** 3) a11, a12, a21, a22, b1, b2 = symbols('a11, a12, a21, a22, b1, b2') assert solveset_real(x**3 - 15*x - 4, x) == FiniteSet( -2 + 3 ** S.Half, S(4), -2 - 3 ** S.Half) assert solveset_real(sqrt(x) - 1, x) == FiniteSet(1) assert solveset_real(sqrt(x) - 2, x) == FiniteSet(4) assert solveset_real(x**Rational(1, 4) - 2, x) == FiniteSet(16) assert solveset_real(x**Rational(1, 3) - 3, x) == FiniteSet(27) assert len(solveset_real(x**5 + x**3 + 1, x)) == 1 assert len(solveset_real(-2*x**3 + 4*x**2 - 2*x + 6, x)) > 0 assert solveset_real(x**6 + x**4 + I, x) is S.EmptySet def test_return_root_of(): f = x**5 - 15*x**3 - 5*x**2 + 10*x + 20 s = list(solveset_complex(f, x)) for root in s: assert root.func == CRootOf # if one uses solve to get the roots of a polynomial that has a CRootOf # solution, make sure that the use of nfloat during the solve process # doesn't fail. Note: if you want numerical solutions to a polynomial # it is *much* faster to use nroots to get them than to solve the # equation only to get CRootOf solutions which are then numerically # evaluated. So for eq = x**5 + 3*x + 7 do Poly(eq).nroots() rather # than [i.n() for i in solve(eq)] to get the numerical roots of eq. assert nfloat(list(solveset_complex(x**5 + 3*x**3 + 7, x))[0], exponent=False) == CRootOf(x**5 + 3*x**3 + 7, 0).n() sol = list(solveset_complex(x**6 - 2*x + 2, x)) assert all(isinstance(i, CRootOf) for i in sol) and len(sol) == 6 f = x**5 - 15*x**3 - 5*x**2 + 10*x + 20 s = list(solveset_complex(f, x)) for root in s: assert root.func == CRootOf s = x**5 + 4*x**3 + 3*x**2 + Rational(7, 4) assert solveset_complex(s, x) == \ FiniteSet(*Poly(s*4, domain='ZZ').all_roots()) # Refer issue #7876 eq = x*(x - 1)**2*(x + 1)*(x**6 - x + 1) assert solveset_complex(eq, x) == \ FiniteSet(-1, 0, 1, CRootOf(x**6 - x + 1, 0), CRootOf(x**6 - x + 1, 1), CRootOf(x**6 - x + 1, 2), CRootOf(x**6 - x + 1, 3), CRootOf(x**6 - x + 1, 4), CRootOf(x**6 - x + 1, 5)) def test_solveset_sqrt_1(): assert solveset_real(sqrt(5*x + 6) - 2 - x, x) == \ FiniteSet(-S.One, S(2)) assert solveset_real(sqrt(x - 1) - x + 7, x) == FiniteSet(10) assert solveset_real(sqrt(x - 2) - 5, x) == FiniteSet(27) assert solveset_real(sqrt(x) - 2 - 5, x) == FiniteSet(49) assert solveset_real(sqrt(x**3), x) == FiniteSet(0) assert solveset_real(sqrt(x - 1), x) == FiniteSet(1) def test_solveset_sqrt_2(): x = Symbol('x', real=True) y = Symbol('y', real=True) # http://tutorial.math.lamar.edu/Classes/Alg/SolveRadicalEqns.aspx#Solve_Rad_Ex2_a assert solveset_real(sqrt(2*x - 1) - sqrt(x - 4) - 2, x) == \ FiniteSet(S(5), S(13)) assert solveset_real(sqrt(x + 7) + 2 - sqrt(3 - x), x) == \ FiniteSet(-6) # http://www.purplemath.com/modules/solverad.htm assert solveset_real(sqrt(17*x - sqrt(x**2 - 5)) - 7, x) == \ FiniteSet(3) eq = x + 1 - (x**4 + 4*x**3 - x)**Rational(1, 4) assert solveset_real(eq, x) == FiniteSet(Rational(-1, 2), Rational(-1, 3)) eq = sqrt(2*x + 9) - sqrt(x + 1) - sqrt(x + 4) assert solveset_real(eq, x) == FiniteSet(0) eq = sqrt(x + 4) + sqrt(2*x - 1) - 3*sqrt(x - 1) assert solveset_real(eq, x) == FiniteSet(5) eq = sqrt(x)*sqrt(x - 7) - 12 assert solveset_real(eq, x) == FiniteSet(16) eq = sqrt(x - 3) + sqrt(x) - 3 assert solveset_real(eq, x) == FiniteSet(4) eq = sqrt(2*x**2 - 7) - (3 - x) assert solveset_real(eq, x) == FiniteSet(-S(8), S(2)) # others eq = sqrt(9*x**2 + 4) - (3*x + 2) assert solveset_real(eq, x) == FiniteSet(0) assert solveset_real(sqrt(x - 3) - sqrt(x) - 3, x) == FiniteSet() eq = (2*x - 5)**Rational(1, 3) - 3 assert solveset_real(eq, x) == FiniteSet(16) assert solveset_real(sqrt(x) + sqrt(sqrt(x)) - 4, x) == \ FiniteSet((Rational(-1, 2) + sqrt(17)/2)**4) eq = sqrt(x) - sqrt(x - 1) + sqrt(sqrt(x)) assert solveset_real(eq, x) == FiniteSet() eq = (x - 4)**2 + (sqrt(x) - 2)**4 assert solveset_real(eq, x) == FiniteSet(-4, 4) eq = (sqrt(x) + sqrt(x + 1) + sqrt(1 - x) - 6*sqrt(5)/5) ans = solveset_real(eq, x) ra = S('''-1484/375 - 4*(-1/2 + sqrt(3)*I/2)*(-12459439/52734375 + 114*sqrt(12657)/78125)**(1/3) - 172564/(140625*(-1/2 + sqrt(3)*I/2)*(-12459439/52734375 + 114*sqrt(12657)/78125)**(1/3))''') rb = Rational(4, 5) assert all(abs(eq.subs(x, i).n()) < 1e-10 for i in (ra, rb)) and \ len(ans) == 2 and \ {i.n(chop=True) for i in ans} == \ {i.n(chop=True) for i in (ra, rb)} assert solveset_real(sqrt(x) + x**Rational(1, 3) + x**Rational(1, 4), x) == FiniteSet(0) assert solveset_real(x/sqrt(x**2 + 1), x) == FiniteSet(0) eq = (x - y**3)/((y**2)*sqrt(1 - y**2)) assert solveset_real(eq, x) == FiniteSet(y**3) # issue 4497 assert solveset_real(1/(5 + x)**Rational(1, 5) - 9, x) == \ FiniteSet(Rational(-295244, 59049)) @XFAIL def test_solve_sqrt_fail(): # this only works if we check real_root(eq.subs(x, Rational(1, 3))) # but checksol doesn't work like that eq = (x**3 - 3*x**2)**Rational(1, 3) + 1 - x assert solveset_real(eq, x) == FiniteSet(Rational(1, 3)) @slow def test_solve_sqrt_3(): R = Symbol('R') eq = sqrt(2)*R*sqrt(1/(R + 1)) + (R + 1)*(sqrt(2)*sqrt(1/(R + 1)) - 1) sol = solveset_complex(eq, R) fset = [Rational(5, 3) + 4*sqrt(10)*cos(atan(3*sqrt(111)/251)/3)/3, -sqrt(10)*cos(atan(3*sqrt(111)/251)/3)/3 + 40*re(1/((Rational(-1, 2) - sqrt(3)*I/2)*(Rational(251, 27) + sqrt(111)*I/9)**Rational(1, 3)))/9 + sqrt(30)*sin(atan(3*sqrt(111)/251)/3)/3 + Rational(5, 3) + I*(-sqrt(30)*cos(atan(3*sqrt(111)/251)/3)/3 - sqrt(10)*sin(atan(3*sqrt(111)/251)/3)/3 + 40*im(1/((Rational(-1, 2) - sqrt(3)*I/2)*(Rational(251, 27) + sqrt(111)*I/9)**Rational(1, 3)))/9)] cset = [40*re(1/((Rational(-1, 2) + sqrt(3)*I/2)*(Rational(251, 27) + sqrt(111)*I/9)**Rational(1, 3)))/9 - sqrt(10)*cos(atan(3*sqrt(111)/251)/3)/3 - sqrt(30)*sin(atan(3*sqrt(111)/251)/3)/3 + Rational(5, 3) + I*(40*im(1/((Rational(-1, 2) + sqrt(3)*I/2)*(Rational(251, 27) + sqrt(111)*I/9)**Rational(1, 3)))/9 - sqrt(10)*sin(atan(3*sqrt(111)/251)/3)/3 + sqrt(30)*cos(atan(3*sqrt(111)/251)/3)/3)] assert sol._args[0] == FiniteSet(*fset) assert sol._args[1] == ConditionSet( R, Eq(sqrt(2)*R*sqrt(1/(R + 1)) + (R + 1)*(sqrt(2)*sqrt(1/(R + 1)) - 1), 0), FiniteSet(*cset)) # the number of real roots will depend on the value of m: for m=1 there are 4 # and for m=-1 there are none. eq = -sqrt((m - q)**2 + (-m/(2*q) + S.Half)**2) + sqrt((-m**2/2 - sqrt( 4*m**4 - 4*m**2 + 8*m + 1)/4 - Rational(1, 4))**2 + (m**2/2 - m - sqrt( 4*m**4 - 4*m**2 + 8*m + 1)/4 - Rational(1, 4))**2) unsolved_object = ConditionSet(q, Eq(sqrt((m - q)**2 + (-m/(2*q) + S.Half)**2) - sqrt((-m**2/2 - sqrt(4*m**4 - 4*m**2 + 8*m + 1)/4 - Rational(1, 4))**2 + (m**2/2 - m - sqrt(4*m**4 - 4*m**2 + 8*m + 1)/4 - Rational(1, 4))**2), 0), S.Reals) assert solveset_real(eq, q) == unsolved_object def test_solve_polynomial_symbolic_param(): assert solveset_complex((x**2 - 1)**2 - a, x) == \ FiniteSet(sqrt(1 + sqrt(a)), -sqrt(1 + sqrt(a)), sqrt(1 - sqrt(a)), -sqrt(1 - sqrt(a))) # issue 4507 assert solveset_complex(y - b/(1 + a*x), x) == \ FiniteSet((b/y - 1)/a) - FiniteSet(-1/a) # issue 4508 assert solveset_complex(y - b*x/(a + x), x) == \ FiniteSet(-a*y/(y - b)) - FiniteSet(-a) def test_solve_rational(): assert solveset_real(1/x + 1, x) == FiniteSet(-S.One) assert solveset_real(1/exp(x) - 1, x) == FiniteSet(0) assert solveset_real(x*(1 - 5/x), x) == FiniteSet(5) assert solveset_real(2*x/(x + 2) - 1, x) == FiniteSet(2) assert solveset_real((x**2/(7 - x)).diff(x), x) == \ FiniteSet(S.Zero, S(14)) def test_solveset_real_gen_is_pow(): assert solveset_real(sqrt(1) + 1, x) == EmptySet() def test_no_sol(): assert solveset(1 - oo*x) == EmptySet() assert solveset(oo*x, x) == EmptySet() assert solveset(oo*x - oo, x) == EmptySet() assert solveset_real(4, x) == EmptySet() assert solveset_real(exp(x), x) == EmptySet() assert solveset_real(x**2 + 1, x) == EmptySet() assert solveset_real(-3*a/sqrt(x), x) == EmptySet() assert solveset_real(1/x, x) == EmptySet() assert solveset_real(-(1 + x)/(2 + x)**2 + 1/(2 + x), x) == \ EmptySet() def test_sol_zero_real(): assert solveset_real(0, x) == S.Reals assert solveset(0, x, Interval(1, 2)) == Interval(1, 2) assert solveset_real(-x**2 - 2*x + (x + 1)**2 - 1, x) == S.Reals def test_no_sol_rational_extragenous(): assert solveset_real((x/(x + 1) + 3)**(-2), x) == EmptySet() assert solveset_real((x - 1)/(1 + 1/(x - 1)), x) == EmptySet() def test_solve_polynomial_cv_1a(): """ Test for solving on equations that can be converted to a polynomial equation using the change of variable y -> x**Rational(p, q) """ assert solveset_real(sqrt(x) - 1, x) == FiniteSet(1) assert solveset_real(sqrt(x) - 2, x) == FiniteSet(4) assert solveset_real(x**Rational(1, 4) - 2, x) == FiniteSet(16) assert solveset_real(x**Rational(1, 3) - 3, x) == FiniteSet(27) assert solveset_real(x*(x**(S.One / 3) - 3), x) == \ FiniteSet(S.Zero, S(27)) def test_solveset_real_rational(): """Test solveset_real for rational functions""" x = Symbol('x', real=True) y = Symbol('y', real=True) assert solveset_real((x - y**3) / ((y**2)*sqrt(1 - y**2)), x) \ == FiniteSet(y**3) # issue 4486 assert solveset_real(2*x/(x + 2) - 1, x) == FiniteSet(2) def test_solveset_real_log(): assert solveset_real(log((x-1)*(x+1)), x) == \ FiniteSet(sqrt(2), -sqrt(2)) def test_poly_gens(): assert solveset_real(4**(2*(x**2) + 2*x) - 8, x) == \ FiniteSet(Rational(-3, 2), S.Half) def test_solve_abs(): n = Dummy('n') raises(ValueError, lambda: solveset(Abs(x) - 1, x)) assert solveset(Abs(x) - n, x, S.Reals).dummy_eq( ConditionSet(x, Contains(n, Interval(0, oo)), {-n, n})) assert solveset_real(Abs(x) - 2, x) == FiniteSet(-2, 2) assert solveset_real(Abs(x) + 2, x) is S.EmptySet assert solveset_real(Abs(x + 3) - 2*Abs(x - 3), x) == \ FiniteSet(1, 9) assert solveset_real(2*Abs(x) - Abs(x - 1), x) == \ FiniteSet(-1, Rational(1, 3)) sol = ConditionSet( x, And( Contains(b, Interval(0, oo)), Contains(a + b, Interval(0, oo)), Contains(a - b, Interval(0, oo))), FiniteSet(-a - b - 3, -a + b - 3, a - b - 3, a + b - 3)) eq = Abs(Abs(x + 3) - a) - b assert invert_real(eq, 0, x)[1] == sol reps = {a: 3, b: 1} eqab = eq.subs(reps) for si in sol.subs(reps): assert not eqab.subs(x, si) assert dumeq(solveset(Eq(sin(Abs(x)), 1), x, domain=S.Reals), Union( Intersection(Interval(0, oo), ImageSet(Lambda(n, (-1)**n*pi/2 + n*pi), S.Integers)), Intersection(Interval(-oo, 0), ImageSet(Lambda(n, n*pi - (-1)**(-n)*pi/2), S.Integers)))) def test_issue_9824(): assert dumeq(solveset(sin(x)**2 - 2*sin(x) + 1, x), ImageSet(Lambda(n, 2*n*pi + pi/2), S.Integers)) assert dumeq(solveset(cos(x)**2 - 2*cos(x) + 1, x), ImageSet(Lambda(n, 2*n*pi), S.Integers)) def test_issue_9565(): assert solveset_real(Abs((x - 1)/(x - 5)) <= Rational(1, 3), x) == Interval(-1, 2) def test_issue_10069(): eq = abs(1/(x - 1)) - 1 > 0 assert solveset_real(eq, x) == Union( Interval.open(0, 1), Interval.open(1, 2)) def test_real_imag_splitting(): a, b = symbols('a b', real=True) assert solveset_real(sqrt(a**2 - b**2) - 3, a) == \ FiniteSet(-sqrt(b**2 + 9), sqrt(b**2 + 9)) assert solveset_real(sqrt(a**2 + b**2) - 3, a) != \ S.EmptySet def test_units(): assert solveset_real(1/x - 1/(2*cm), x) == FiniteSet(2*cm) def test_solve_only_exp_1(): y = Symbol('y', positive=True) assert solveset_real(exp(x) - y, x) == FiniteSet(log(y)) assert solveset_real(exp(x) + exp(-x) - 4, x) == \ FiniteSet(log(-sqrt(3) + 2), log(sqrt(3) + 2)) assert solveset_real(exp(x) + exp(-x) - y, x) != S.EmptySet def test_atan2(): # The .inverse() method on atan2 works only if x.is_real is True and the # second argument is a real constant assert solveset_real(atan2(x, 2) - pi/3, x) == FiniteSet(2*sqrt(3)) def test_piecewise_solveset(): eq = Piecewise((x - 2, Gt(x, 2)), (2 - x, True)) - 3 assert set(solveset_real(eq, x)) == set(FiniteSet(-1, 5)) absxm3 = Piecewise( (x - 3, 0 <= x - 3), (3 - x, 0 > x - 3)) y = Symbol('y', positive=True) assert solveset_real(absxm3 - y, x) == FiniteSet(-y + 3, y + 3) f = Piecewise(((x - 2)**2, x >= 0), (0, True)) assert solveset(f, x, domain=S.Reals) == Union(FiniteSet(2), Interval(-oo, 0, True, True)) assert solveset( Piecewise((x + 1, x > 0), (I, True)) - I, x, S.Reals ) == Interval(-oo, 0) assert solveset(Piecewise((x - 1, Ne(x, I)), (x, True)), x) == FiniteSet(1) # issue 19718 g = Piecewise((1, x > 10), (0, True)) assert solveset(g > 0, x, S.Reals) == Interval.open(10, oo) from sympy.logic.boolalg import BooleanTrue f = BooleanTrue() assert solveset(f, x, domain=Interval(-3, 10)) == Interval(-3, 10) # issue 20552 f = Piecewise((0, Eq(x, 0)), (x**2/Abs(x), True)) g = Piecewise((0, Eq(x, pi)), ((x - pi)/sin(x), True)) assert solveset(f, x, domain=S.Reals) == FiniteSet(0) assert solveset(g) == FiniteSet(pi) def test_solveset_complex_polynomial(): assert solveset_complex(a*x**2 + b*x + c, x) == \ FiniteSet(-b/(2*a) - sqrt(-4*a*c + b**2)/(2*a), -b/(2*a) + sqrt(-4*a*c + b**2)/(2*a)) assert solveset_complex(x - y**3, y) == FiniteSet( (-x**Rational(1, 3))/2 + I*sqrt(3)*x**Rational(1, 3)/2, x**Rational(1, 3), (-x**Rational(1, 3))/2 - I*sqrt(3)*x**Rational(1, 3)/2) assert solveset_complex(x + 1/x - 1, x) == \ FiniteSet(S.Half + I*sqrt(3)/2, S.Half - I*sqrt(3)/2) def test_sol_zero_complex(): assert solveset_complex(0, x) == S.Complexes def test_solveset_complex_rational(): assert solveset_complex((x - 1)*(x - I)/(x - 3), x) == \ FiniteSet(1, I) assert solveset_complex((x - y**3)/((y**2)*sqrt(1 - y**2)), x) == \ FiniteSet(y**3) assert solveset_complex(-x**2 - I, x) == \ FiniteSet(-sqrt(2)/2 + sqrt(2)*I/2, sqrt(2)/2 - sqrt(2)*I/2) def test_solve_quintics(): skip("This test is too slow") f = x**5 - 110*x**3 - 55*x**2 + 2310*x + 979 s = solveset_complex(f, x) for root in s: res = f.subs(x, root.n()).n() assert tn(res, 0) f = x**5 + 15*x + 12 s = solveset_complex(f, x) for root in s: res = f.subs(x, root.n()).n() assert tn(res, 0) def test_solveset_complex_exp(): from sympy.abc import x, n assert dumeq(solveset_complex(exp(x) - 1, x), imageset(Lambda(n, I*2*n*pi), S.Integers)) assert dumeq(solveset_complex(exp(x) - I, x), imageset(Lambda(n, I*(2*n*pi + pi/2)), S.Integers)) assert solveset_complex(1/exp(x), x) == S.EmptySet assert dumeq(solveset_complex(sinh(x).rewrite(exp), x), imageset(Lambda(n, n*pi*I), S.Integers)) def test_solveset_real_exp(): from sympy.abc import x, y assert solveset(Eq((-2)**x, 4), x, S.Reals) == FiniteSet(2) assert solveset(Eq(-2**x, 4), x, S.Reals) == S.EmptySet assert solveset(Eq((-3)**x, 27), x, S.Reals) == S.EmptySet assert solveset(Eq((-5)**(x+1), 625), x, S.Reals) == FiniteSet(3) assert solveset(Eq(2**(x-3), -16), x, S.Reals) == S.EmptySet assert solveset(Eq((-3)**(x - 3), -3**39), x, S.Reals) == FiniteSet(42) assert solveset(Eq(2**x, y), x, S.Reals) == Intersection(S.Reals, FiniteSet(log(y)/log(2))) assert invert_real((-2)**(2*x) - 16, 0, x) == (x, FiniteSet(2)) def test_solve_complex_log(): assert solveset_complex(log(x), x) == FiniteSet(1) assert solveset_complex(1 - log(a + 4*x**2), x) == \ FiniteSet(-sqrt(-a + E)/2, sqrt(-a + E)/2) def test_solve_complex_sqrt(): assert solveset_complex(sqrt(5*x + 6) - 2 - x, x) == \ FiniteSet(-S.One, S(2)) assert solveset_complex(sqrt(5*x + 6) - (2 + 2*I) - x, x) == \ FiniteSet(-S(2), 3 - 4*I) assert solveset_complex(4*x*(1 - a * sqrt(x)), x) == \ FiniteSet(S.Zero, 1 / a ** 2) def test_solveset_complex_tan(): s = solveset_complex(tan(x).rewrite(exp), x) assert dumeq(s, imageset(Lambda(n, pi*n), S.Integers) - \ imageset(Lambda(n, pi*n + pi/2), S.Integers)) @_both_exp_pow def test_solve_trig(): from sympy.abc import n assert dumeq(solveset_real(sin(x), x), Union(imageset(Lambda(n, 2*pi*n), S.Integers), imageset(Lambda(n, 2*pi*n + pi), S.Integers))) assert dumeq(solveset_real(sin(x) - 1, x), imageset(Lambda(n, 2*pi*n + pi/2), S.Integers)) assert dumeq(solveset_real(cos(x), x), Union(imageset(Lambda(n, 2*pi*n + pi/2), S.Integers), imageset(Lambda(n, 2*pi*n + pi*Rational(3, 2)), S.Integers))) assert dumeq(solveset_real(sin(x) + cos(x), x), Union(imageset(Lambda(n, 2*n*pi + pi*Rational(3, 4)), S.Integers), imageset(Lambda(n, 2*n*pi + pi*Rational(7, 4)), S.Integers))) assert solveset_real(sin(x)**2 + cos(x)**2, x) == S.EmptySet assert dumeq(solveset_complex(cos(x) - S.Half, x), Union(imageset(Lambda(n, 2*n*pi + pi*Rational(5, 3)), S.Integers), imageset(Lambda(n, 2*n*pi + pi/3), S.Integers))) assert dumeq(solveset(sin(y + a) - sin(y), a, domain=S.Reals), Union(ImageSet(Lambda(n, 2*n*pi), S.Integers), Intersection(ImageSet(Lambda(n, -I*(I*( 2*n*pi + arg(-exp(-2*I*y))) + 2*im(y))), S.Integers), S.Reals))) assert dumeq(solveset_real(sin(2*x)*cos(x) + cos(2*x)*sin(x)-1, x), ImageSet(Lambda(n, n*pi*Rational(2, 3) + pi/6), S.Integers)) assert dumeq(solveset_real(2*tan(x)*sin(x) + 1, x), Union( ImageSet(Lambda(n, 2*n*pi + atan(sqrt(2)*sqrt(-1 + sqrt(17))/ (1 - sqrt(17))) + pi), S.Integers), ImageSet(Lambda(n, 2*n*pi - atan(sqrt(2)*sqrt(-1 + sqrt(17))/ (1 - sqrt(17))) + pi), S.Integers))) assert dumeq(solveset_real(cos(2*x)*cos(4*x) - 1, x), ImageSet(Lambda(n, n*pi), S.Integers)) assert dumeq(solveset(sin(x/10) + Rational(3, 4)), Union( ImageSet(Lambda(n, 20*n*pi + 10*atan(3*sqrt(7)/7) + 10*pi), S.Integers), ImageSet(Lambda(n, 20*n*pi - 10*atan(3*sqrt(7)/7) + 20*pi), S.Integers))) assert dumeq(solveset(cos(x/15) + cos(x/5)), Union( ImageSet(Lambda(n, 30*n*pi + 15*pi/2), S.Integers), ImageSet(Lambda(n, 30*n*pi + 45*pi/2), S.Integers), ImageSet(Lambda(n, 30*n*pi + 75*pi/4), S.Integers), ImageSet(Lambda(n, 30*n*pi + 45*pi/4), S.Integers), ImageSet(Lambda(n, 30*n*pi + 105*pi/4), S.Integers), ImageSet(Lambda(n, 30*n*pi + 15*pi/4), S.Integers))) assert dumeq(solveset(sec(sqrt(2)*x/3) + 5), Union( ImageSet(Lambda(n, 3*sqrt(2)*(2*n*pi - pi + atan(2*sqrt(6)))/2), S.Integers), ImageSet(Lambda(n, 3*sqrt(2)*(2*n*pi - atan(2*sqrt(6)) + pi)/2), S.Integers))) assert dumeq(simplify(solveset(tan(pi*x) - cot(pi/2*x))), Union( ImageSet(Lambda(n, 4*n + 1), S.Integers), ImageSet(Lambda(n, 4*n + 3), S.Integers), ImageSet(Lambda(n, 4*n + Rational(7, 3)), S.Integers), ImageSet(Lambda(n, 4*n + Rational(5, 3)), S.Integers), ImageSet(Lambda(n, 4*n + Rational(11, 3)), S.Integers), ImageSet(Lambda(n, 4*n + Rational(1, 3)), S.Integers))) assert dumeq(solveset(cos(9*x)), Union( ImageSet(Lambda(n, 2*n*pi/9 + pi/18), S.Integers), ImageSet(Lambda(n, 2*n*pi/9 + pi/6), S.Integers))) assert dumeq(solveset(sin(8*x) + cot(12*x), x, S.Reals), Union( ImageSet(Lambda(n, n*pi/2 + pi/8), S.Integers), ImageSet(Lambda(n, n*pi/2 + 3*pi/8), S.Integers), ImageSet(Lambda(n, n*pi/2 + 5*pi/16), S.Integers), ImageSet(Lambda(n, n*pi/2 + 3*pi/16), S.Integers), ImageSet(Lambda(n, n*pi/2 + 7*pi/16), S.Integers), ImageSet(Lambda(n, n*pi/2 + pi/16), S.Integers))) # This is the only remaining solveset test that actually ends up being solved # by _solve_trig2(). All others are handled by the improved _solve_trig1. assert dumeq(solveset_real(2*cos(x)*cos(2*x) - 1, x), Union(ImageSet(Lambda(n, 2*n*pi + 2*atan(sqrt(-2*2**Rational(1, 3)*(67 + 9*sqrt(57))**Rational(2, 3) + 8*2**Rational(2, 3) + 11*(67 + 9*sqrt(57))**Rational(1, 3))/(3*(67 + 9*sqrt(57))**Rational(1, 6)))), S.Integers), ImageSet(Lambda(n, 2*n*pi - 2*atan(sqrt(-2*2**Rational(1, 3)*(67 + 9*sqrt(57))**Rational(2, 3) + 8*2**Rational(2, 3) + 11*(67 + 9*sqrt(57))**Rational(1, 3))/(3*(67 + 9*sqrt(57))**Rational(1, 6))) + 2*pi), S.Integers))) # issue #16870 assert dumeq(simplify(solveset(sin(x/180*pi) - S.Half, x, S.Reals)), Union( ImageSet(Lambda(n, 360*n + 150), S.Integers), ImageSet(Lambda(n, 360*n + 30), S.Integers))) def test_solve_hyperbolic(): # actual solver: _solve_trig1 n = Dummy('n') assert solveset(sinh(x) + cosh(x), x) == S.EmptySet assert solveset(sinh(x) + cos(x), x) == ConditionSet(x, Eq(cos(x) + sinh(x), 0), S.Complexes) assert solveset_real(sinh(x) + sech(x), x) == FiniteSet( log(sqrt(sqrt(5) - 2))) assert solveset_real(3*cosh(2*x) - 5, x) == FiniteSet( -log(3)/2, log(3)/2) assert solveset_real(sinh(x - 3) - 2, x) == FiniteSet( log((2 + sqrt(5))*exp(3))) assert solveset_real(cosh(2*x) + 2*sinh(x) - 5, x) == FiniteSet( log(-2 + sqrt(5)), log(1 + sqrt(2))) assert solveset_real((coth(x) + sinh(2*x))/cosh(x) - 3, x) == FiniteSet( log(S.Half + sqrt(5)/2), log(1 + sqrt(2))) assert solveset_real(cosh(x)*sinh(x) - 2, x) == FiniteSet( log(4 + sqrt(17))/2) assert solveset_real(sinh(x) + tanh(x) - 1, x) == FiniteSet( log(sqrt(2)/2 + sqrt(-S(1)/2 + sqrt(2)))) assert dumeq(solveset_complex(sinh(x) - I/2, x), Union( ImageSet(Lambda(n, I*(2*n*pi + 5*pi/6)), S.Integers), ImageSet(Lambda(n, I*(2*n*pi + pi/6)), S.Integers))) assert dumeq(solveset_complex(sinh(x) + sech(x), x), Union( ImageSet(Lambda(n, 2*n*I*pi + log(sqrt(-2 + sqrt(5)))), S.Integers), ImageSet(Lambda(n, I*(2*n*pi + pi/2) + log(sqrt(2 + sqrt(5)))), S.Integers), ImageSet(Lambda(n, I*(2*n*pi + pi) + log(sqrt(-2 + sqrt(5)))), S.Integers), ImageSet(Lambda(n, I*(2*n*pi - pi/2) + log(sqrt(2 + sqrt(5)))), S.Integers))) assert dumeq(solveset(sinh(x/10) + Rational(3, 4)), Union( ImageSet(Lambda(n, 10*I*(2*n*pi + pi) + 10*log(2)), S.Integers), ImageSet(Lambda(n, 20*n*I*pi - 10*log(2)), S.Integers))) assert dumeq(solveset(cosh(x/15) + cosh(x/5)), Union( ImageSet(Lambda(n, 15*I*(2*n*pi + pi/2)), S.Integers), ImageSet(Lambda(n, 15*I*(2*n*pi - pi/2)), S.Integers), ImageSet(Lambda(n, 15*I*(2*n*pi - 3*pi/4)), S.Integers), ImageSet(Lambda(n, 15*I*(2*n*pi + 3*pi/4)), S.Integers), ImageSet(Lambda(n, 15*I*(2*n*pi - pi/4)), S.Integers), ImageSet(Lambda(n, 15*I*(2*n*pi + pi/4)), S.Integers))) assert dumeq(solveset(sech(sqrt(2)*x/3) + 5), Union( ImageSet(Lambda(n, 3*sqrt(2)*I*(2*n*pi - pi + atan(2*sqrt(6)))/2), S.Integers), ImageSet(Lambda(n, 3*sqrt(2)*I*(2*n*pi - atan(2*sqrt(6)) + pi)/2), S.Integers))) assert dumeq(solveset(tanh(pi*x) - coth(pi/2*x)), Union( ImageSet(Lambda(n, 2*I*(2*n*pi + pi/2)/pi), S.Integers), ImageSet(Lambda(n, 2*I*(2*n*pi - pi/2)/pi), S.Integers))) assert dumeq(solveset(cosh(9*x)), Union( ImageSet(Lambda(n, I*(2*n*pi + pi/2)/9), S.Integers), ImageSet(Lambda(n, I*(2*n*pi - pi/2)/9), S.Integers))) # issues #9606 / #9531: assert solveset(sinh(x), x, S.Reals) == FiniteSet(0) assert dumeq(solveset(sinh(x), x, S.Complexes), Union( ImageSet(Lambda(n, I*(2*n*pi + pi)), S.Integers), ImageSet(Lambda(n, 2*n*I*pi), S.Integers))) # issues #11218 / #18427 assert dumeq(solveset(sin(pi*x), x, S.Reals), Union( ImageSet(Lambda(n, (2*n*pi + pi)/pi), S.Integers), ImageSet(Lambda(n, 2*n), S.Integers))) assert dumeq(solveset(sin(pi*x), x), Union( ImageSet(Lambda(n, (2*n*pi + pi)/pi), S.Integers), ImageSet(Lambda(n, 2*n), S.Integers))) # issue #17543 assert dumeq(simplify(solveset(I*cot(8*x - 8*E), x)), Union( ImageSet(Lambda(n, n*pi/4 - 13*pi/16 + E), S.Integers), ImageSet(Lambda(n, n*pi/4 - 11*pi/16 + E), S.Integers))) # issues #18490 / #19489 assert solveset(cosh(x) + cosh(3*x) - cosh(5*x), x, S.Reals ).dummy_eq(ConditionSet(x, Eq(cosh(x) + cosh(3*x) - cosh(5*x), 0), S.Reals)) assert solveset(sinh(8*x) + coth(12*x)).dummy_eq( ConditionSet(x, Eq(sinh(8*x) + coth(12*x), 0), S.Complexes)) def test_solve_trig_hyp_symbolic(): # actual solver: _solve_trig1 assert dumeq(solveset(sin(a*x), x), ConditionSet(x, Ne(a, 0), Union( ImageSet(Lambda(n, (2*n*pi + pi)/a), S.Integers), ImageSet(Lambda(n, 2*n*pi/a), S.Integers)))) assert dumeq(solveset(cosh(x/a), x), ConditionSet(x, Ne(a, 0), Union( ImageSet(Lambda(n, I*a*(2*n*pi + pi/2)), S.Integers), ImageSet(Lambda(n, I*a*(2*n*pi - pi/2)), S.Integers)))) assert dumeq(solveset(sin(2*sqrt(3)/3*a**2/(b*pi)*x) + cos(4*sqrt(3)/3*a**2/(b*pi)*x), x), ConditionSet(x, Ne(b, 0) & Ne(a**2, 0), Union( ImageSet(Lambda(n, sqrt(3)*pi*b*(2*n*pi + pi/2)/(2*a**2)), S.Integers), ImageSet(Lambda(n, sqrt(3)*pi*b*(2*n*pi - 5*pi/6)/(2*a**2)), S.Integers), ImageSet(Lambda(n, sqrt(3)*pi*b*(2*n*pi - pi/6)/(2*a**2)), S.Integers)))) assert dumeq(simplify(solveset(cot((1 + I)*x) - cot((3 + 3*I)*x), x)), Union( ImageSet(Lambda(n, pi*(1 - I)*(4*n + 1)/4), S.Integers), ImageSet(Lambda(n, pi*(1 - I)*(4*n - 1)/4), S.Integers))) assert dumeq(solveset(cosh((a**2 + 1)*x) - 3, x), ConditionSet(x, Ne(a**2 + 1, 0), Union( ImageSet(Lambda(n, (2*n*I*pi + log(3 - 2*sqrt(2)))/(a**2 + 1)), S.Integers), ImageSet(Lambda(n, (2*n*I*pi + log(2*sqrt(2) + 3))/(a**2 + 1)), S.Integers)))) ar = Symbol('ar', real=True) assert solveset(cosh((ar**2 + 1)*x) - 2, x, S.Reals) == FiniteSet( log(sqrt(3) + 2)/(ar**2 + 1), log(2 - sqrt(3))/(ar**2 + 1)) def test_issue_9616(): assert dumeq(solveset(sinh(x) + tanh(x) - 1, x), Union( ImageSet(Lambda(n, 2*n*I*pi + log(sqrt(2)/2 + sqrt(-S.Half + sqrt(2)))), S.Integers), ImageSet(Lambda(n, I*(2*n*pi - atan(sqrt(2)*sqrt(S.Half + sqrt(2))) + pi) + log(sqrt(1 + sqrt(2)))), S.Integers), ImageSet(Lambda(n, I*(2*n*pi + pi) + log(-sqrt(2)/2 + sqrt(-S.Half + sqrt(2)))), S.Integers), ImageSet(Lambda(n, I*(2*n*pi - pi + atan(sqrt(2)*sqrt(S.Half + sqrt(2)))) + log(sqrt(1 + sqrt(2)))), S.Integers))) f1 = (sinh(x)).rewrite(exp) f2 = (tanh(x)).rewrite(exp) assert dumeq(solveset(f1 + f2 - 1, x), Union( Complement(ImageSet( Lambda(n, I*(2*n*pi + pi) + log(-sqrt(2)/2 + sqrt(-S.Half + sqrt(2)))), S.Integers), ImageSet(Lambda(n, I*(2*n*pi + pi)/2), S.Integers)), Complement(ImageSet(Lambda(n, I*(2*n*pi - pi + atan(sqrt(2)*sqrt(S.Half + sqrt(2)))) + log(sqrt(1 + sqrt(2)))), S.Integers), ImageSet(Lambda(n, I*(2*n*pi + pi)/2), S.Integers)), Complement(ImageSet(Lambda(n, I*(2*n*pi - atan(sqrt(2)*sqrt(S.Half + sqrt(2))) + pi) + log(sqrt(1 + sqrt(2)))), S.Integers), ImageSet(Lambda(n, I*(2*n*pi + pi)/2), S.Integers)), Complement( ImageSet(Lambda(n, 2*n*I*pi + log(sqrt(2)/2 + sqrt(-S.Half + sqrt(2)))), S.Integers), ImageSet(Lambda(n, I*(2*n*pi + pi)/2), S.Integers)))) def test_solve_invalid_sol(): assert 0 not in solveset_real(sin(x)/x, x) assert 0 not in solveset_complex((exp(x) - 1)/x, x) @XFAIL def test_solve_trig_simplified(): from sympy.abc import n assert dumeq(solveset_real(sin(x), x), imageset(Lambda(n, n*pi), S.Integers)) assert dumeq(solveset_real(cos(x), x), imageset(Lambda(n, n*pi + pi/2), S.Integers)) assert dumeq(solveset_real(cos(x) + sin(x), x), imageset(Lambda(n, n*pi - pi/4), S.Integers)) @XFAIL def test_solve_lambert(): assert solveset_real(x*exp(x) - 1, x) == FiniteSet(LambertW(1)) assert solveset_real(exp(x) + x, x) == FiniteSet(-LambertW(1)) assert solveset_real(x + 2**x, x) == \ FiniteSet(-LambertW(log(2))/log(2)) # issue 4739 ans = solveset_real(3*x + 5 + 2**(-5*x + 3), x) assert ans == FiniteSet(Rational(-5, 3) + LambertW(-10240*2**Rational(1, 3)*log(2)/3)/(5*log(2))) eq = 2*(3*x + 4)**5 - 6*7**(3*x + 9) result = solveset_real(eq, x) ans = FiniteSet((log(2401) + 5*LambertW(-log(7**(7*3**Rational(1, 5)/5))))/(3*log(7))/-1) assert result == ans assert solveset_real(eq.expand(), x) == result assert solveset_real(5*x - 1 + 3*exp(2 - 7*x), x) == \ FiniteSet(Rational(1, 5) + LambertW(-21*exp(Rational(3, 5))/5)/7) assert solveset_real(2*x + 5 + log(3*x - 2), x) == \ FiniteSet(Rational(2, 3) + LambertW(2*exp(Rational(-19, 3))/3)/2) assert solveset_real(3*x + log(4*x), x) == \ FiniteSet(LambertW(Rational(3, 4))/3) assert solveset_real(x**x - 2) == FiniteSet(exp(LambertW(log(2)))) a = Symbol('a') assert solveset_real(-a*x + 2*x*log(x), x) == FiniteSet(exp(a/2)) a = Symbol('a', real=True) assert solveset_real(a/x + exp(x/2), x) == \ FiniteSet(2*LambertW(-a/2)) assert solveset_real((a/x + exp(x/2)).diff(x), x) == \ FiniteSet(4*LambertW(sqrt(2)*sqrt(a)/4)) # coverage test assert solveset_real(tanh(x + 3)*tanh(x - 3) - 1, x) == EmptySet() assert solveset_real((x**2 - 2*x + 1).subs(x, log(x) + 3*x), x) == \ FiniteSet(LambertW(3*S.Exp1)/3) assert solveset_real((x**2 - 2*x + 1).subs(x, (log(x) + 3*x)**2 - 1), x) == \ FiniteSet(LambertW(3*exp(-sqrt(2)))/3, LambertW(3*exp(sqrt(2)))/3) assert solveset_real((x**2 - 2*x - 2).subs(x, log(x) + 3*x), x) == \ FiniteSet(LambertW(3*exp(1 + sqrt(3)))/3, LambertW(3*exp(-sqrt(3) + 1))/3) assert solveset_real(x*log(x) + 3*x + 1, x) == \ FiniteSet(exp(-3 + LambertW(-exp(3)))) eq = (x*exp(x) - 3).subs(x, x*exp(x)) assert solveset_real(eq, x) == \ FiniteSet(LambertW(3*exp(-LambertW(3)))) assert solveset_real(3*log(a**(3*x + 5)) + a**(3*x + 5), x) == \ FiniteSet(-((log(a**5) + LambertW(Rational(1, 3)))/(3*log(a)))) p = symbols('p', positive=True) assert solveset_real(3*log(p**(3*x + 5)) + p**(3*x + 5), x) == \ FiniteSet( log((-3**Rational(1, 3) - 3**Rational(5, 6)*I)*LambertW(Rational(1, 3))**Rational(1, 3)/(2*p**Rational(5, 3)))/log(p), log((-3**Rational(1, 3) + 3**Rational(5, 6)*I)*LambertW(Rational(1, 3))**Rational(1, 3)/(2*p**Rational(5, 3)))/log(p), log((3*LambertW(Rational(1, 3))/p**5)**(1/(3*log(p)))),) # checked numerically # check collection b = Symbol('b') eq = 3*log(a**(3*x + 5)) + b*log(a**(3*x + 5)) + a**(3*x + 5) assert solveset_real(eq, x) == FiniteSet( -((log(a**5) + LambertW(1/(b + 3)))/(3*log(a)))) # issue 4271 assert solveset_real((a/x + exp(x/2)).diff(x, 2), x) == FiniteSet( 6*LambertW((-1)**Rational(1, 3)*a**Rational(1, 3)/3)) assert solveset_real(x**3 - 3**x, x) == \ FiniteSet(-3/log(3)*LambertW(-log(3)/3)) assert solveset_real(3**cos(x) - cos(x)**3) == FiniteSet( acos(-3*LambertW(-log(3)/3)/log(3))) assert solveset_real(x**2 - 2**x, x) == \ solveset_real(-x**2 + 2**x, x) assert solveset_real(3*log(x) - x*log(3)) == FiniteSet( -3*LambertW(-log(3)/3)/log(3), -3*LambertW(-log(3)/3, -1)/log(3)) assert solveset_real(LambertW(2*x) - y) == FiniteSet( y*exp(y)/2) @XFAIL def test_other_lambert(): a = Rational(6, 5) assert solveset_real(x**a - a**x, x) == FiniteSet( a, -a*LambertW(-log(a)/a)/log(a)) @_both_exp_pow def test_solveset(): f = Function('f') raises(ValueError, lambda: solveset(x + y)) assert solveset(x, 1) == S.EmptySet assert solveset(f(1)**2 + y + 1, f(1) ) == FiniteSet(-sqrt(-y - 1), sqrt(-y - 1)) assert solveset(f(1)**2 - 1, f(1), S.Reals) == FiniteSet(-1, 1) assert solveset(f(1)**2 + 1, f(1)) == FiniteSet(-I, I) assert solveset(x - 1, 1) == FiniteSet(x) assert solveset(sin(x) - cos(x), sin(x)) == FiniteSet(cos(x)) assert solveset(0, domain=S.Reals) == S.Reals assert solveset(1) == S.EmptySet assert solveset(True, domain=S.Reals) == S.Reals # issue 10197 assert solveset(False, domain=S.Reals) == S.EmptySet assert solveset(exp(x) - 1, domain=S.Reals) == FiniteSet(0) assert solveset(exp(x) - 1, x, S.Reals) == FiniteSet(0) assert solveset(Eq(exp(x), 1), x, S.Reals) == FiniteSet(0) assert solveset(exp(x) - 1, exp(x), S.Reals) == FiniteSet(1) A = Indexed('A', x) assert solveset(A - 1, A, S.Reals) == FiniteSet(1) assert solveset(x - 1 >= 0, x, S.Reals) == Interval(1, oo) assert solveset(exp(x) - 1 >= 0, x, S.Reals) == Interval(0, oo) assert dumeq(solveset(exp(x) - 1, x), imageset(Lambda(n, 2*I*pi*n), S.Integers)) assert dumeq(solveset(Eq(exp(x), 1), x), imageset(Lambda(n, 2*I*pi*n), S.Integers)) # issue 13825 assert solveset(x**2 + f(0) + 1, x) == {-sqrt(-f(0) - 1), sqrt(-f(0) - 1)} # issue 19977 assert solveset(atan(log(x)) > 0, x, domain=Interval.open(0, oo)) == Interval.open(1, oo) @_both_exp_pow def test_multi_exp(): k1, k2, k3 = symbols('k1, k2, k3') assert dumeq(solveset(exp(exp(x)) - 5, x),\ imageset(Lambda(((k1, n),), I*(2*k1*pi + arg(2*n*I*pi + log(5))) + log(Abs(2*n*I*pi + log(5)))),\ ProductSet(S.Integers, S.Integers))) assert dumeq(solveset((d*exp(exp(a*x + b)) + c), x),\ imageset(Lambda(x, (-b + x)/a), ImageSet(Lambda(((k1, n),), \ I*(2*k1*pi + arg(I*(2*n*pi + arg(-c/d)) + log(Abs(c/d)))) + log(Abs(I*(2*n*pi + arg(-c/d)) + log(Abs(c/d))))), \ ProductSet(S.Integers, S.Integers)))) assert dumeq(solveset((d*exp(exp(exp(a*x + b))) + c), x),\ imageset(Lambda(x, (-b + x)/a), ImageSet(Lambda(((k2, k1, n),), \ I*(2*k2*pi + arg(I*(2*k1*pi + arg(I*(2*n*pi + arg(-c/d)) + log(Abs(c/d)))) + \ log(Abs(I*(2*n*pi + arg(-c/d)) + log(Abs(c/d)))))) + log(Abs(I*(2*k1*pi + arg(I*(2*n*pi + arg(-c/d)) + \ log(Abs(c/d)))) + log(Abs(I*(2*n*pi + arg(-c/d)) + log(Abs(c/d))))))), \ ProductSet(S.Integers, S.Integers, S.Integers)))) assert dumeq(solveset((d*exp(exp(exp(exp(a*x + b)))) + c), x),\ ImageSet(Lambda(x, (-b + x)/a), ImageSet(Lambda(((k3, k2, k1, n),), \ I*(2*k3*pi + arg(I*(2*k2*pi + arg(I*(2*k1*pi + arg(I*(2*n*pi + arg(-c/d)) + log(Abs(c/d)))) + \ log(Abs(I*(2*n*pi + arg(-c/d)) + log(Abs(c/d)))))) + log(Abs(I*(2*k1*pi + arg(I*(2*n*pi + arg(-c/d)) + \ log(Abs(c/d)))) + log(Abs(I*(2*n*pi + arg(-c/d)) + log(Abs(c/d)))))))) + log(Abs(I*(2*k2*pi + \ arg(I*(2*k1*pi + arg(I*(2*n*pi + arg(-c/d)) + log(Abs(c/d)))) + log(Abs(I*(2*n*pi + arg(-c/d)) + log(Abs(c/d)))))) + \ log(Abs(I*(2*k1*pi + arg(I*(2*n*pi + arg(-c/d)) + log(Abs(c/d)))) + log(Abs(I*(2*n*pi + arg(-c/d)) + log(Abs(c/d))))))))), \ ProductSet(S.Integers, S.Integers, S.Integers, S.Integers)))) def test__solveset_multi(): from sympy.solvers.solveset import _solveset_multi from sympy import Reals # Basic univariate case: from sympy.abc import x assert _solveset_multi([x**2-1], [x], [S.Reals]) == FiniteSet((1,), (-1,)) # Linear systems of two equations from sympy.abc import x, y assert _solveset_multi([x+y, x+1], [x, y], [Reals, Reals]) == FiniteSet((-1, 1)) assert _solveset_multi([x+y, x+1], [y, x], [Reals, Reals]) == FiniteSet((1, -1)) assert _solveset_multi([x+y, x-y-1], [x, y], [Reals, Reals]) == FiniteSet((S(1)/2, -S(1)/2)) assert _solveset_multi([x-1, y-2], [x, y], [Reals, Reals]) == FiniteSet((1, 2)) # assert dumeq(_solveset_multi([x+y], [x, y], [Reals, Reals]), ImageSet(Lambda(x, (x, -x)), Reals)) assert dumeq(_solveset_multi([x+y], [x, y], [Reals, Reals]), Union( ImageSet(Lambda(((x,),), (x, -x)), ProductSet(Reals)), ImageSet(Lambda(((y,),), (-y, y)), ProductSet(Reals)))) assert _solveset_multi([x+y, x+y+1], [x, y], [Reals, Reals]) == S.EmptySet assert _solveset_multi([x+y, x-y, x-1], [x, y], [Reals, Reals]) == S.EmptySet assert _solveset_multi([x+y, x-y, x-1], [y, x], [Reals, Reals]) == S.EmptySet # Systems of three equations: from sympy.abc import x, y, z assert _solveset_multi([x+y+z-1, x+y-z-2, x-y-z-3], [x, y, z], [Reals, Reals, Reals]) == FiniteSet((2, -S.Half, -S.Half)) # Nonlinear systems: from sympy.abc import r, theta, z, x, y assert _solveset_multi([x**2+y**2-2, x+y], [x, y], [Reals, Reals]) == FiniteSet((-1, 1), (1, -1)) assert _solveset_multi([x**2-1, y], [x, y], [Reals, Reals]) == FiniteSet((1, 0), (-1, 0)) #assert _solveset_multi([x**2-y**2], [x, y], [Reals, Reals]) == Union( # ImageSet(Lambda(x, (x, -x)), Reals), ImageSet(Lambda(x, (x, x)), Reals)) assert dumeq(_solveset_multi([x**2-y**2], [x, y], [Reals, Reals]), Union( ImageSet(Lambda(((x,),), (x, -Abs(x))), ProductSet(Reals)), ImageSet(Lambda(((x,),), (x, Abs(x))), ProductSet(Reals)), ImageSet(Lambda(((y,),), (-Abs(y), y)), ProductSet(Reals)), ImageSet(Lambda(((y,),), (Abs(y), y)), ProductSet(Reals)))) assert _solveset_multi([r*cos(theta)-1, r*sin(theta)], [theta, r], [Interval(0, pi), Interval(-1, 1)]) == FiniteSet((0, 1), (pi, -1)) assert _solveset_multi([r*cos(theta)-1, r*sin(theta)], [r, theta], [Interval(0, 1), Interval(0, pi)]) == FiniteSet((1, 0)) #assert _solveset_multi([r*cos(theta)-r, r*sin(theta)], [r, theta], # [Interval(0, 1), Interval(0, pi)]) == ? assert dumeq(_solveset_multi([r*cos(theta)-r, r*sin(theta)], [r, theta], [Interval(0, 1), Interval(0, pi)]), Union( ImageSet(Lambda(((r,),), (r, 0)), ImageSet(Lambda(r, (r,)), Interval(0, 1))), ImageSet(Lambda(((theta,),), (0, theta)), ImageSet(Lambda(theta, (theta,)), Interval(0, pi))))) def test_conditionset(): assert solveset(Eq(sin(x)**2 + cos(x)**2, 1), x, domain=S.Reals ) is S.Reals assert solveset(Eq(x**2 + x*sin(x), 1), x, domain=S.Reals ).dummy_eq(ConditionSet(x, Eq(x**2 + x*sin(x) - 1, 0), S.Reals)) assert dumeq(solveset(Eq(-I*(exp(I*x) - exp(-I*x))/2, 1), x ), imageset(Lambda(n, 2*n*pi + pi/2), S.Integers)) assert solveset(x + sin(x) > 1, x, domain=S.Reals ).dummy_eq(ConditionSet(x, x + sin(x) > 1, S.Reals)) assert solveset(Eq(sin(Abs(x)), x), x, domain=S.Reals ).dummy_eq(ConditionSet(x, Eq(-x + sin(Abs(x)), 0), S.Reals)) assert solveset(y**x-z, x, S.Reals ).dummy_eq(ConditionSet(x, Eq(y**x - z, 0), S.Reals)) @XFAIL def test_conditionset_equality(): ''' Checking equality of different representations of ConditionSet''' assert solveset(Eq(tan(x), y), x) == ConditionSet(x, Eq(tan(x), y), S.Complexes) def test_solveset_domain(): assert solveset(x**2 - x - 6, x, Interval(0, oo)) == FiniteSet(3) assert solveset(x**2 - 1, x, Interval(0, oo)) == FiniteSet(1) assert solveset(x**4 - 16, x, Interval(0, 10)) == FiniteSet(2) def test_improve_coverage(): solution = solveset(exp(x) + sin(x), x, S.Reals) unsolved_object = ConditionSet(x, Eq(exp(x) + sin(x), 0), S.Reals) assert solution.dummy_eq(unsolved_object) def test_issue_9522(): expr1 = Eq(1/(x**2 - 4) + x, 1/(x**2 - 4) + 2) expr2 = Eq(1/x + x, 1/x) assert solveset(expr1, x, S.Reals) == EmptySet() assert solveset(expr2, x, S.Reals) == EmptySet() def test_solvify(): assert solvify(x**2 + 10, x, S.Reals) == [] assert solvify(x**3 + 1, x, S.Complexes) == [-1, S.Half - sqrt(3)*I/2, S.Half + sqrt(3)*I/2] assert solvify(log(x), x, S.Reals) == [1] assert solvify(cos(x), x, S.Reals) == [pi/2, pi*Rational(3, 2)] assert solvify(sin(x) + 1, x, S.Reals) == [pi*Rational(3, 2)] raises(NotImplementedError, lambda: solvify(sin(exp(x)), x, S.Complexes)) def test_solvify_piecewise(): p1 = Piecewise((0, x < -1), (x**2, x <= 1), (log(x), True)) p2 = Piecewise((0, x < -10), (x**2 + 5*x - 6, x >= -9)) p3 = Piecewise((0, Eq(x, 0)), (x**2/Abs(x), True)) p4 = Piecewise((0, Eq(x, pi)), ((x - pi)/sin(x), True)) # issue 21079 assert solvify(p1, x, S.Reals) == [0] assert solvify(p2, x, S.Reals) == [-6, 1] assert solvify(p3, x, S.Reals) == [0] assert solvify(p4, x, S.Reals) == [pi] def test_abs_invert_solvify(): x = Symbol('x',positive=True) assert solvify(sin(Abs(x)), x, S.Reals) == [0, pi] x = Symbol('x') assert solvify(sin(Abs(x)), x, S.Reals) is None def test_linear_eq_to_matrix(): eqns1 = [2*x + y - 2*z - 3, x - y - z, x + y + 3*z - 12] eqns2 = [Eq(3*x + 2*y - z, 1), Eq(2*x - 2*y + 4*z, -2), -2*x + y - 2*z] A, B = linear_eq_to_matrix(eqns1, x, y, z) assert A == Matrix([[2, 1, -2], [1, -1, -1], [1, 1, 3]]) assert B == Matrix([[3], [0], [12]]) A, B = linear_eq_to_matrix(eqns2, x, y, z) assert A == Matrix([[3, 2, -1], [2, -2, 4], [-2, 1, -2]]) assert B == Matrix([[1], [-2], [0]]) # Pure symbolic coefficients eqns3 = [a*b*x + b*y + c*z - d, e*x + d*x + f*y + g*z - h, i*x + j*y + k*z - l] A, B = linear_eq_to_matrix(eqns3, x, y, z) assert A == Matrix([[a*b, b, c], [d + e, f, g], [i, j, k]]) assert B == Matrix([[d], [h], [l]]) # raise ValueError if # 1) no symbols are given raises(ValueError, lambda: linear_eq_to_matrix(eqns3)) # 2) there are duplicates raises(ValueError, lambda: linear_eq_to_matrix(eqns3, [x, x, y])) # 3) there are non-symbols raises(ValueError, lambda: linear_eq_to_matrix(eqns3, [x, 1/a, y])) # 4) a nonlinear term is detected in the original expression raises(NonlinearError, lambda: linear_eq_to_matrix(Eq(1/x + x, 1/x), [x])) assert linear_eq_to_matrix(1, x) == (Matrix([[0]]), Matrix([[-1]])) # issue 15195 assert linear_eq_to_matrix(x + y*(z*(3*x + 2) + 3), x) == ( Matrix([[3*y*z + 1]]), Matrix([[-y*(2*z + 3)]])) assert linear_eq_to_matrix(Matrix( [[a*x + b*y - 7], [5*x + 6*y - c]]), x, y) == ( Matrix([[a, b], [5, 6]]), Matrix([[7], [c]])) # issue 15312 assert linear_eq_to_matrix(Eq(x + 2, 1), x) == ( Matrix([[1]]), Matrix([[-1]])) def test_issue_16577(): assert linear_eq_to_matrix(Eq(a*(2*x + 3*y) + 4*y, 5), x, y) == ( Matrix([[2*a, 3*a + 4]]), Matrix([[5]])) def test_linsolve(): x1, x2, x3, x4 = symbols('x1, x2, x3, x4') # Test for different input forms M = Matrix([[1, 2, 1, 1, 7], [1, 2, 2, -1, 12], [2, 4, 0, 6, 4]]) system1 = A, B = M[:, :-1], M[:, -1] Eqns = [x1 + 2*x2 + x3 + x4 - 7, x1 + 2*x2 + 2*x3 - x4 - 12, 2*x1 + 4*x2 + 6*x4 - 4] sol = FiniteSet((-2*x2 - 3*x4 + 2, x2, 2*x4 + 5, x4)) assert linsolve(Eqns, (x1, x2, x3, x4)) == sol assert linsolve(Eqns, *(x1, x2, x3, x4)) == sol assert linsolve(system1, (x1, x2, x3, x4)) == sol assert linsolve(system1, *(x1, x2, x3, x4)) == sol # issue 9667 - symbols can be Dummy symbols x1, x2, x3, x4 = symbols('x:4', cls=Dummy) assert linsolve(system1, x1, x2, x3, x4) == FiniteSet( (-2*x2 - 3*x4 + 2, x2, 2*x4 + 5, x4)) # raise ValueError for garbage value raises(ValueError, lambda: linsolve(Eqns)) raises(ValueError, lambda: linsolve(x1)) raises(ValueError, lambda: linsolve(x1, x2)) raises(ValueError, lambda: linsolve((A,), x1, x2)) raises(ValueError, lambda: linsolve(A, B, x1, x2)) #raise ValueError if equations are non-linear in given variables raises(NonlinearError, lambda: linsolve([x + y - 1, x ** 2 + y - 3], [x, y])) raises(NonlinearError, lambda: linsolve([cos(x) + y, x + y], [x, y])) assert linsolve([x + z - 1, x ** 2 + y - 3], [z, y]) == {(-x + 1, -x**2 + 3)} # Fully symbolic test A = Matrix([[a, b], [c, d]]) B = Matrix([[e], [g]]) system2 = (A, B) sol = FiniteSet(((-b*g + d*e)/(a*d - b*c), (a*g - c*e)/(a*d - b*c))) assert linsolve(system2, [x, y]) == sol # No solution A = Matrix([[1, 2, 3], [2, 4, 6], [3, 6, 9]]) B = Matrix([0, 0, 1]) assert linsolve((A, B), (x, y, z)) == EmptySet() # Issue #10056 A, B, J1, J2 = symbols('A B J1 J2') Augmatrix = Matrix([ [2*I*J1, 2*I*J2, -2/J1], [-2*I*J2, -2*I*J1, 2/J2], [0, 2, 2*I/(J1*J2)], [2, 0, 0], ]) assert linsolve(Augmatrix, A, B) == FiniteSet((0, I/(J1*J2))) # Issue #10121 - Assignment of free variables Augmatrix = Matrix([[0, 1, 0, 0, 0, 0], [0, 0, 0, 1, 0, 0]]) assert linsolve(Augmatrix, a, b, c, d, e) == FiniteSet((a, 0, c, 0, e)) #raises(IndexError, lambda: linsolve(Augmatrix, a, b, c)) x0, x1, x2, _x0 = symbols('tau0 tau1 tau2 _tau0') assert linsolve(Matrix([[0, 1, 0, 0, 0, 0], [0, 0, 0, 1, 0, _x0]]) ) == FiniteSet((x0, 0, x1, _x0, x2)) x0, x1, x2, _x0 = symbols('tau00 tau01 tau02 tau0') assert linsolve(Matrix([[0, 1, 0, 0, 0, 0], [0, 0, 0, 1, 0, _x0]]) ) == FiniteSet((x0, 0, x1, _x0, x2)) x0, x1, x2, _x0 = symbols('tau00 tau01 tau02 tau1') assert linsolve(Matrix([[0, 1, 0, 0, 0, 0], [0, 0, 0, 1, 0, _x0]]) ) == FiniteSet((x0, 0, x1, _x0, x2)) # symbols can be given as generators x0, x2, x4 = symbols('x0, x2, x4') assert linsolve(Augmatrix, numbered_symbols('x') ) == FiniteSet((x0, 0, x2, 0, x4)) Augmatrix[-1, -1] = x0 # use Dummy to avoid clash; the names may clash but the symbols # will not Augmatrix[-1, -1] = symbols('_x0') assert len(linsolve( Augmatrix, numbered_symbols('x', cls=Dummy)).free_symbols) == 4 # Issue #12604 f = Function('f') assert linsolve([f(x) - 5], f(x)) == FiniteSet((5,)) # Issue #14860 from sympy.physics.units import meter, newton, kilo kN = kilo*newton Eqns = [8*kN + x + y, 28*kN*meter + 3*x*meter] assert linsolve(Eqns, x, y) == { (kilo*newton*Rational(-28, 3), kN*Rational(4, 3))} # linsolve fully expands expressions, so removable singularities # and other nonlinearity does not raise an error assert linsolve([Eq(x, x + y)], [x, y]) == {(x, 0)} assert linsolve([Eq(1/x, 1/x + y)], [x, y]) == {(x, 0)} assert linsolve([Eq(y/x, y/x + y)], [x, y]) == {(x, 0)} assert linsolve([Eq(x*(x + 1), x**2 + y)], [x, y]) == {(y, y)} # corner cases # # XXX: The case below should give the same as for [0] # assert linsolve([], [x]) == {(x,)} assert linsolve([], [x]) == EmptySet() assert linsolve([0], [x]) == {(x,)} assert linsolve([x], [x, y]) == {(0, y)} assert linsolve([x, 0], [x, y]) == {(0, y)} def test_linsolve_large_sparse(): # # This is mainly a performance test # def _mk_eqs_sol(n): xs = symbols('x:{}'.format(n)) ys = symbols('y:{}'.format(n)) syms = xs + ys eqs = [] sol = (-S.Half,) * n + (S.Half,) * n for xi, yi in zip(xs, ys): eqs.extend([xi + yi, xi - yi + 1]) return eqs, syms, FiniteSet(sol) n = 500 eqs, syms, sol = _mk_eqs_sol(n) assert linsolve(eqs, syms) == sol def test_linsolve_immutable(): A = ImmutableDenseMatrix([[1, 1, 2], [0, 1, 2], [0, 0, 1]]) B = ImmutableDenseMatrix([2, 1, -1]) assert linsolve([A, B], (x, y, z)) == FiniteSet((1, 3, -1)) A = ImmutableDenseMatrix([[1, 1, 7], [1, -1, 3]]) assert linsolve(A) == FiniteSet((5, 2)) def test_solve_decomposition(): n = Dummy('n') f1 = exp(3*x) - 6*exp(2*x) + 11*exp(x) - 6 f2 = sin(x)**2 - 2*sin(x) + 1 f3 = sin(x)**2 - sin(x) f4 = sin(x + 1) f5 = exp(x + 2) - 1 f6 = 1/log(x) f7 = 1/x s1 = ImageSet(Lambda(n, 2*n*pi), S.Integers) s2 = ImageSet(Lambda(n, 2*n*pi + pi), S.Integers) s3 = ImageSet(Lambda(n, 2*n*pi + pi/2), S.Integers) s4 = ImageSet(Lambda(n, 2*n*pi - 1), S.Integers) s5 = ImageSet(Lambda(n, 2*n*pi - 1 + pi), S.Integers) assert solve_decomposition(f1, x, S.Reals) == FiniteSet(0, log(2), log(3)) assert dumeq(solve_decomposition(f2, x, S.Reals), s3) assert dumeq(solve_decomposition(f3, x, S.Reals), Union(s1, s2, s3)) assert dumeq(solve_decomposition(f4, x, S.Reals), Union(s4, s5)) assert solve_decomposition(f5, x, S.Reals) == FiniteSet(-2) assert solve_decomposition(f6, x, S.Reals) == S.EmptySet assert solve_decomposition(f7, x, S.Reals) == S.EmptySet assert solve_decomposition(x, x, Interval(1, 2)) == S.EmptySet # nonlinsolve testcases def test_nonlinsolve_basic(): assert nonlinsolve([],[]) == S.EmptySet assert nonlinsolve([],[x, y]) == S.EmptySet system = [x, y - x - 5] assert nonlinsolve([x],[x, y]) == FiniteSet((0, y)) assert nonlinsolve(system, [y]) == FiniteSet((x + 5,)) soln = (ImageSet(Lambda(n, 2*n*pi + pi/2), S.Integers),) assert dumeq(nonlinsolve([sin(x) - 1], [x]), FiniteSet(tuple(soln))) assert nonlinsolve([x**2 - 1], [x]) == FiniteSet((-1,), (1,)) soln = FiniteSet((y, y)) assert nonlinsolve([x - y, 0], x, y) == soln assert nonlinsolve([0, x - y], x, y) == soln assert nonlinsolve([x - y, x - y], x, y) == soln assert nonlinsolve([x, 0], x, y) == FiniteSet((0, y)) f = Function('f') assert nonlinsolve([f(x), 0], f(x), y) == FiniteSet((0, y)) assert nonlinsolve([f(x), 0], f(x), f(y)) == FiniteSet((0, f(y))) A = Indexed('A', x) assert nonlinsolve([A, 0], A, y) == FiniteSet((0, y)) assert nonlinsolve([x**2 -1], [sin(x)]) == FiniteSet((S.EmptySet,)) assert nonlinsolve([x**2 -1], sin(x)) == FiniteSet((S.EmptySet,)) assert nonlinsolve([x**2 -1], 1) == FiniteSet((x**2,)) assert nonlinsolve([x**2 -1], x + y) == FiniteSet((S.EmptySet,)) assert nonlinsolve([Eq(1, x + y), Eq(1, -x + y - 1), Eq(1, -x + y - 1)], x, y) == FiniteSet( (-S.Half, 3*S.Half)) def test_nonlinsolve_abs(): soln = FiniteSet((y, y), (-y, y)) assert nonlinsolve([Abs(x) - y], x, y) == soln def test_raise_exception_nonlinsolve(): raises(IndexError, lambda: nonlinsolve([x**2 -1], [])) raises(ValueError, lambda: nonlinsolve([x**2 -1])) raises(NotImplementedError, lambda: nonlinsolve([(x+y)**2 - 9, x**2 - y**2 - 0.75], (x, y))) def test_trig_system(): # TODO: add more simple testcases when solveset returns # simplified soln for Trig eq assert nonlinsolve([sin(x) - 1, cos(x) -1 ], x) == S.EmptySet soln1 = (ImageSet(Lambda(n, 2*n*pi + pi/2), S.Integers),) soln = FiniteSet(soln1) assert dumeq(nonlinsolve([sin(x) - 1, cos(x)], x), soln) @XFAIL def test_trig_system_fail(): # fails because solveset trig solver is not much smart. sys = [x + y - pi/2, sin(x) + sin(y) - 1] # solveset returns conditionset for sin(x) + sin(y) - 1 soln_1 = (ImageSet(Lambda(n, n*pi + pi/2), S.Integers), ImageSet(Lambda(n, n*pi), S.Integers)) soln_1 = FiniteSet(soln_1) soln_2 = (ImageSet(Lambda(n, n*pi), S.Integers), ImageSet(Lambda(n, n*pi+ pi/2), S.Integers)) soln_2 = FiniteSet(soln_2) soln = soln_1 + soln_2 assert dumeq(nonlinsolve(sys, [x, y]), soln) # Add more cases from here # http://www.vitutor.com/geometry/trigonometry/equations_systems.html#uno sys = [sin(x) + sin(y) - (sqrt(3)+1)/2, sin(x) - sin(y) - (sqrt(3) - 1)/2] soln_x = Union(ImageSet(Lambda(n, 2*n*pi + pi/3), S.Integers), ImageSet(Lambda(n, 2*n*pi + pi*Rational(2, 3)), S.Integers)) soln_y = Union(ImageSet(Lambda(n, 2*n*pi + pi/6), S.Integers), ImageSet(Lambda(n, 2*n*pi + pi*Rational(5, 6)), S.Integers)) assert dumeq(nonlinsolve(sys, [x, y]), FiniteSet((soln_x, soln_y))) def test_nonlinsolve_positive_dimensional(): x, y, z, a, b, c, d = symbols('x, y, z, a, b, c, d', extended_real=True) assert nonlinsolve([x*y, x*y - x], [x, y]) == FiniteSet((0, y)) system = [a**2 + a*c, a - b] assert nonlinsolve(system, [a, b]) == FiniteSet((0, 0), (-c, -c)) # here (a= 0, b = 0) is independent soln so both is printed. # if symbols = [a, b, c] then only {a : -c ,b : -c} eq1 = a + b + c + d eq2 = a*b + b*c + c*d + d*a eq3 = a*b*c + b*c*d + c*d*a + d*a*b eq4 = a*b*c*d - 1 system = [eq1, eq2, eq3, eq4] sol1 = (-1/d, -d, 1/d, FiniteSet(d) - FiniteSet(0)) sol2 = (1/d, -d, -1/d, FiniteSet(d) - FiniteSet(0)) soln = FiniteSet(sol1, sol2) assert nonlinsolve(system, [a, b, c, d]) == soln def test_nonlinsolve_polysys(): x, y, z = symbols('x, y, z', real=True) assert nonlinsolve([x**2 + y - 2, x**2 + y], [x, y]) == S.EmptySet s = (-y + 2, y) assert nonlinsolve([(x + y)**2 - 4, x + y - 2], [x, y]) == FiniteSet(s) system = [x**2 - y**2] soln_real = FiniteSet((-y, y), (y, y)) soln_complex = FiniteSet((-Abs(y), y), (Abs(y), y)) soln =soln_real + soln_complex assert nonlinsolve(system, [x, y]) == soln system = [x**2 - y**2] soln_real= FiniteSet((y, -y), (y, y)) soln_complex = FiniteSet((y, -Abs(y)), (y, Abs(y))) soln = soln_real + soln_complex assert nonlinsolve(system, [y, x]) == soln system = [x**2 + y - 3, x - y - 4] assert nonlinsolve(system, (x, y)) != nonlinsolve(system, (y, x)) def test_nonlinsolve_using_substitution(): x, y, z, n = symbols('x, y, z, n', real = True) system = [(x + y)*n - y**2 + 2] s_x = (n*y - y**2 + 2)/n soln = (-s_x, y) assert nonlinsolve(system, [x, y]) == FiniteSet(soln) system = [z**2*x**2 - z**2*y**2/exp(x)] soln_real_1 = (y, x, 0) soln_real_2 = (-exp(x/2)*Abs(x), x, z) soln_real_3 = (exp(x/2)*Abs(x), x, z) soln_complex_1 = (-x*exp(x/2), x, z) soln_complex_2 = (x*exp(x/2), x, z) syms = [y, x, z] soln = FiniteSet(soln_real_1, soln_complex_1, soln_complex_2,\ soln_real_2, soln_real_3) assert nonlinsolve(system,syms) == soln def test_nonlinsolve_complex(): n = Dummy('n') assert dumeq(nonlinsolve([exp(x) - sin(y), 1/y - 3], [x, y]), { (ImageSet(Lambda(n, 2*n*I*pi + log(sin(Rational(1, 3)))), S.Integers), Rational(1, 3))}) system = [exp(x) - sin(y), 1/exp(y) - 3] assert dumeq(nonlinsolve(system, [x, y]), { (ImageSet(Lambda(n, I*(2*n*pi + pi) + log(sin(log(3)))), S.Integers), -log(3)), (ImageSet(Lambda(n, I*(2*n*pi + arg(sin(2*n*I*pi - log(3)))) + log(Abs(sin(2*n*I*pi - log(3))))), S.Integers), ImageSet(Lambda(n, 2*n*I*pi - log(3)), S.Integers))}) system = [exp(x) - sin(y), y**2 - 4] assert dumeq(nonlinsolve(system, [x, y]), { (ImageSet(Lambda(n, I*(2*n*pi + pi) + log(sin(2))), S.Integers), -2), (ImageSet(Lambda(n, 2*n*I*pi + log(sin(2))), S.Integers), 2)}) @XFAIL def test_solve_nonlinear_trans(): # After the transcendental equation solver these will work x, y, z = symbols('x, y, z', real=True) soln1 = FiniteSet((2*LambertW(y/2), y)) soln2 = FiniteSet((-x*sqrt(exp(x)), y), (x*sqrt(exp(x)), y)) soln3 = FiniteSet((x*exp(x/2), x)) soln4 = FiniteSet(2*LambertW(y/2), y) assert nonlinsolve([x**2 - y**2/exp(x)], [x, y]) == soln1 assert nonlinsolve([x**2 - y**2/exp(x)], [y, x]) == soln2 assert nonlinsolve([x**2 - y**2/exp(x)], [y, x]) == soln3 assert nonlinsolve([x**2 - y**2/exp(x)], [x, y]) == soln4 def test_issue_19050(): # test_issue_19050 --> TypeError removed assert dumeq(nonlinsolve([x + y, sin(y)], [x, y]), FiniteSet((ImageSet(Lambda(n, -2*n*pi), S.Integers), ImageSet(Lambda(n, 2*n*pi), S.Integers)),\ (ImageSet(Lambda(n, -2*n*pi - pi), S.Integers), ImageSet(Lambda(n, 2*n*pi + pi), S.Integers)))) assert dumeq(nonlinsolve([x + y, sin(y) + cos(y)], [x, y]), FiniteSet((ImageSet(Lambda(n, -2*n*pi - 3*pi/4), S.Integers), ImageSet(Lambda(n, 2*n*pi + 3*pi/4), S.Integers)), \ (ImageSet(Lambda(n, -2*n*pi - 7*pi/4), S.Integers), ImageSet(Lambda(n, 2*n*pi + 7*pi/4), S.Integers)))) def test_issue_16618(): # AttributeError is removed ! eqn = [sin(x)*sin(y), cos(x)*cos(y) - 1] ans = FiniteSet((x, 2*n*pi), (2*n*pi, y), (x, 2*n*pi + pi), (2*n*pi + pi, y)) sol = nonlinsolve(eqn, [x, y]) for i0, j0 in zip(ordered(sol), ordered(ans)): assert len(i0) == len(j0) == 2 assert all(a.dummy_eq(b) for a, b in zip(i0, j0)) assert len(sol) == len(ans) def test_issue_17566(): assert nonlinsolve([32*(2**x)/2**(-y) - 4**y, 27*(3**x) - 1/3**y], x, y) ==\ FiniteSet((-log(81)/log(3), 1)) def test_issue_19587(): n,m = symbols('n m') assert nonlinsolve([32*2**m*2**n - 4**n, 27*3**m - 3**(-n)], m, n) ==\ FiniteSet((-log(81)/log(3), 1)) def test_issue_5132_1(): system = [sqrt(x**2 + y**2) - sqrt(10), x + y - 4] assert nonlinsolve(system, [x, y]) == FiniteSet((1, 3), (3, 1)) n = Dummy('n') eqs = [exp(x)**2 - sin(y) + z**2, 1/exp(y) - 3] s_real_y = -log(3) s_real_z = sqrt(-exp(2*x) - sin(log(3))) soln_real = FiniteSet((s_real_y, s_real_z), (s_real_y, -s_real_z)) lam = Lambda(n, 2*n*I*pi + -log(3)) s_complex_y = ImageSet(lam, S.Integers) lam = Lambda(n, sqrt(-exp(2*x) + sin(2*n*I*pi + -log(3)))) s_complex_z_1 = ImageSet(lam, S.Integers) lam = Lambda(n, -sqrt(-exp(2*x) + sin(2*n*I*pi + -log(3)))) s_complex_z_2 = ImageSet(lam, S.Integers) soln_complex = FiniteSet( (s_complex_y, s_complex_z_1), (s_complex_y, s_complex_z_2) ) soln = soln_real + soln_complex assert dumeq(nonlinsolve(eqs, [y, z]), soln) def test_issue_5132_2(): x, y = symbols('x, y', real=True) eqs = [exp(x)**2 - sin(y) + z**2, 1/exp(y) - 3] n = Dummy('n') soln_real = (log(-z**2 + sin(y))/2, z) lam = Lambda( n, I*(2*n*pi + arg(-z**2 + sin(y)))/2 + log(Abs(z**2 - sin(y)))/2) img = ImageSet(lam, S.Integers) # not sure about the complex soln. But it looks correct. soln_complex = (img, z) soln = FiniteSet(soln_real, soln_complex) assert dumeq(nonlinsolve(eqs, [x, z]), soln) system = [r - x**2 - y**2, tan(t) - y/x] s_x = sqrt(r/(tan(t)**2 + 1)) s_y = sqrt(r/(tan(t)**2 + 1))*tan(t) soln = FiniteSet((s_x, s_y), (-s_x, -s_y)) assert nonlinsolve(system, [x, y]) == soln def test_issue_6752(): a,b,c,d = symbols('a, b, c, d', real=True) assert nonlinsolve([a**2 + a, a - b], [a, b]) == {(-1, -1), (0, 0)} @SKIP("slow") def test_issue_5114_solveset(): # slow testcase from sympy.abc import d, e, f, g, h, i, j, k, l, o, p, q, r # there is no 'a' in the equation set but this is how the # problem was originally posed syms = [a, b, c, f, h, k, n] eqs = [b + r/d - c/d, c*(1/d + 1/e + 1/g) - f/g - r/d, f*(1/g + 1/i + 1/j) - c/g - h/i, h*(1/i + 1/l + 1/m) - f/i - k/m, k*(1/m + 1/o + 1/p) - h/m - n/p, n*(1/p + 1/q) - k/p] assert len(nonlinsolve(eqs, syms)) == 1 @SKIP("Hangs") def _test_issue_5335(): # Not able to check zero dimensional system. # is_zero_dimensional Hangs lam, a0, conc = symbols('lam a0 conc') eqs = [lam + 2*y - a0*(1 - x/2)*x - 0.005*x/2*x, a0*(1 - x/2)*x - 1*y - 0.743436700916726*y, x + y - conc] sym = [x, y, a0] # there are 4 solutions but only two are valid assert len(nonlinsolve(eqs, sym)) == 2 # float eqs = [lam + 2*y - a0*(1 - x/2)*x - 0.005*x/2*x, a0*(1 - x/2)*x - 1*y - 0.743436700916726*y, x + y - conc] sym = [x, y, a0] assert len(nonlinsolve(eqs, sym)) == 2 def test_issue_2777(): # the equations represent two circles x, y = symbols('x y', real=True) e1, e2 = sqrt(x**2 + y**2) - 10, sqrt(y**2 + (-x + 10)**2) - 3 a, b = Rational(191, 20), 3*sqrt(391)/20 ans = {(a, -b), (a, b)} assert nonlinsolve((e1, e2), (x, y)) == ans assert nonlinsolve((e1, e2/(x - a)), (x, y)) == S.EmptySet # make the 2nd circle's radius be -3 e2 += 6 assert nonlinsolve((e1, e2), (x, y)) == S.EmptySet def test_issue_8828(): x1 = 0 y1 = -620 r1 = 920 x2 = 126 y2 = 276 x3 = 51 y3 = 205 r3 = 104 v = [x, y, z] f1 = (x - x1)**2 + (y - y1)**2 - (r1 - z)**2 f2 = (x2 - x)**2 + (y2 - y)**2 - z**2 f3 = (x - x3)**2 + (y - y3)**2 - (r3 - z)**2 F = [f1, f2, f3] g1 = sqrt((x - x1)**2 + (y - y1)**2) + z - r1 g2 = f2 g3 = sqrt((x - x3)**2 + (y - y3)**2) + z - r3 G = [g1, g2, g3] # both soln same A = nonlinsolve(F, v) B = nonlinsolve(G, v) assert A == B def test_nonlinsolve_conditionset(): # when solveset failed to solve all the eq # return conditionset f = Function('f') f1 = f(x) - pi/2 f2 = f(y) - pi*Rational(3, 2) intermediate_system = Eq(2*f(x) - pi, 0) & Eq(2*f(y) - 3*pi, 0) symbols = Tuple(x, y) soln = ConditionSet( symbols, intermediate_system, S.Complexes**2) assert nonlinsolve([f1, f2], [x, y]) == soln def test_substitution_basic(): assert substitution([], [x, y]) == S.EmptySet assert substitution([], []) == S.EmptySet system = [2*x**2 + 3*y**2 - 30, 3*x**2 - 2*y**2 - 19] soln = FiniteSet((-3, -2), (-3, 2), (3, -2), (3, 2)) assert substitution(system, [x, y]) == soln soln = FiniteSet((-1, 1)) assert substitution([x + y], [x], [{y: 1}], [y], set(), [x, y]) == soln assert substitution( [x + y], [x], [{y: 1}], [y], {x + 1}, [y, x]) == S.EmptySet def test_issue_5132_substitution(): x, y, z, r, t = symbols('x, y, z, r, t', real=True) system = [r - x**2 - y**2, tan(t) - y/x] s_x_1 = Complement(FiniteSet(-sqrt(r/(tan(t)**2 + 1))), FiniteSet(0)) s_x_2 = Complement(FiniteSet(sqrt(r/(tan(t)**2 + 1))), FiniteSet(0)) s_y = sqrt(r/(tan(t)**2 + 1))*tan(t) soln = FiniteSet((s_x_2, s_y)) + FiniteSet((s_x_1, -s_y)) assert substitution(system, [x, y]) == soln n = Dummy('n') eqs = [exp(x)**2 - sin(y) + z**2, 1/exp(y) - 3] s_real_y = -log(3) s_real_z = sqrt(-exp(2*x) - sin(log(3))) soln_real = FiniteSet((s_real_y, s_real_z), (s_real_y, -s_real_z)) lam = Lambda(n, 2*n*I*pi + -log(3)) s_complex_y = ImageSet(lam, S.Integers) lam = Lambda(n, sqrt(-exp(2*x) + sin(2*n*I*pi + -log(3)))) s_complex_z_1 = ImageSet(lam, S.Integers) lam = Lambda(n, -sqrt(-exp(2*x) + sin(2*n*I*pi + -log(3)))) s_complex_z_2 = ImageSet(lam, S.Integers) soln_complex = FiniteSet( (s_complex_y, s_complex_z_1), (s_complex_y, s_complex_z_2)) soln = soln_real + soln_complex assert dumeq(substitution(eqs, [y, z]), soln) def test_raises_substitution(): raises(ValueError, lambda: substitution([x**2 -1], [])) raises(TypeError, lambda: substitution([x**2 -1])) raises(ValueError, lambda: substitution([x**2 -1], [sin(x)])) raises(TypeError, lambda: substitution([x**2 -1], x)) raises(TypeError, lambda: substitution([x**2 -1], 1)) def test_issue_21022(): from sympy.core.sympify import sympify eqs = [ 'k-16', 'p-8', 'y*y+z*z-x*x', 'd - x + p', 'd*d+k*k-y*y', 'z*z-p*p-k*k', 'abc-efg', ] efg = Symbol('efg') eqs = [sympify(x) for x in eqs] syb = list(ordered(set.union(*[x.free_symbols for x in eqs]))) res = nonlinsolve(eqs, syb) ans = FiniteSet( (efg, sqrt(-16 + sqrt(640 - 128*sqrt(5))*sqrt(128*sqrt(5) + 640)/16)*sqrt(16 + sqrt(640 - 128*sqrt(5))*sqrt(128*sqrt(5) + 640)/16), efg, 16, 8, 8 + sqrt(-16 + sqrt(640 - 128*sqrt(5))*sqrt(128*sqrt(5) + 640)/16)*sqrt(16 + sqrt(640 - 128*sqrt(5))*sqrt(128*sqrt(5) + 640)/16), sqrt(640 - 128*sqrt(5))*sqrt(128*sqrt(5) + 640)/16, -8*sqrt(5)), (efg, sqrt(-16 + sqrt(640 - 128*sqrt(5))*sqrt(128*sqrt(5) + 640)/16)*sqrt(16 + sqrt(640 - 128*sqrt(5))*sqrt(128*sqrt(5) + 640)/16), efg, 16, 8, 8 + sqrt(-16 + sqrt(640 - 128*sqrt(5))*sqrt(128*sqrt(5) + 640)/16)*sqrt(16 + sqrt(640 - 128*sqrt(5))*sqrt(128*sqrt(5) + 640)/16), sqrt(640 - 128*sqrt(5))*sqrt(128*sqrt(5) + 640)/16, 8*sqrt(5)), (efg, -sqrt(-16 + sqrt(640 - 128*sqrt(5))*sqrt(128*sqrt(5) + 640)/16)*sqrt(16 + sqrt(640 - 128*sqrt(5))*sqrt(128*sqrt(5) + 640)/16), efg, 16, 8, -sqrt(-16 + sqrt(640 - 128*sqrt(5))*sqrt(128*sqrt(5) + 640)/16)*sqrt(16 + sqrt(640 - 128*sqrt(5))*sqrt(128*sqrt(5) + 640)/16) + 8, sqrt(640 - 128*sqrt(5))*sqrt(128*sqrt(5) + 640)/16, -8*sqrt(5)), (efg, -sqrt(-16 + sqrt(640 - 128*sqrt(5))*sqrt(128*sqrt(5) + 640)/16)*sqrt(16 + sqrt(640 - 128*sqrt(5))*sqrt(128*sqrt(5) + 640)/16), efg, 16, 8, -sqrt(-16 + sqrt(640 - 128*sqrt(5))*sqrt(128*sqrt(5) + 640)/16)*sqrt(16 + sqrt(640 - 128*sqrt(5))*sqrt(128*sqrt(5) + 640)/16) + 8, sqrt(640 - 128*sqrt(5))*sqrt(128*sqrt(5) + 640)/16, 8*sqrt(5)) ) assert len(res) == len(ans) == 4 assert res == ans for result in res.args: assert len(result) == 8 def test_issue_17933(): eq1 = x*sin(45) - y*cos(q) eq2 = x*cos(45) - y*sin(q) eq3 = 9*x*sin(45)/10 + y*cos(q) eq4 = 9*x*cos(45)/10 + y*sin(z) - z assert nonlinsolve([eq1, eq2, eq3, eq4], x, y, z, q) ==\ FiniteSet((0, 0, 0, q)) def test_issue_14565(): # removed redundancy assert dumeq(nonlinsolve([k + m, k + m*exp(-2*pi*k)], [k, m]) , FiniteSet((-n*I, ImageSet(Lambda(n, n*I), S.Integers)))) # end of tests for nonlinsolve def test_issue_9556(): b = Symbol('b', positive=True) assert solveset(Abs(x) + 1, x, S.Reals) == EmptySet() assert solveset(Abs(x) + b, x, S.Reals) == EmptySet() assert solveset(Eq(b, -1), b, S.Reals) == EmptySet() def test_issue_9611(): assert solveset(Eq(x - x + a, a), x, S.Reals) == S.Reals assert solveset(Eq(y - y + a, a), y) == S.Complexes def test_issue_9557(): assert solveset(x**2 + a, x, S.Reals) == Intersection(S.Reals, FiniteSet(-sqrt(-a), sqrt(-a))) def test_issue_9778(): x = Symbol('x', real=True) y = Symbol('y', real=True) assert solveset(x**3 + 1, x, S.Reals) == FiniteSet(-1) assert solveset(x**Rational(3, 5) + 1, x, S.Reals) == S.EmptySet assert solveset(x**3 + y, x, S.Reals) == \ FiniteSet(-Abs(y)**Rational(1, 3)*sign(y)) def test_issue_10214(): assert solveset(x**Rational(3, 2) + 4, x, S.Reals) == S.EmptySet assert solveset(x**(Rational(-3, 2)) + 4, x, S.Reals) == S.EmptySet ans = FiniteSet(-2**Rational(2, 3)) assert solveset(x**(S(3)) + 4, x, S.Reals) == ans assert (x**(S(3)) + 4).subs(x,list(ans)[0]) == 0 # substituting ans and verifying the result. assert (x**(S(3)) + 4).subs(x,-(-2)**Rational(2, 3)) == 0 def test_issue_9849(): assert solveset(Abs(sin(x)) + 1, x, S.Reals) == S.EmptySet def test_issue_9953(): assert linsolve([ ], x) == S.EmptySet def test_issue_9913(): assert solveset(2*x + 1/(x - 10)**2, x, S.Reals) == \ FiniteSet(-(3*sqrt(24081)/4 + Rational(4027, 4))**Rational(1, 3)/3 - 100/ (3*(3*sqrt(24081)/4 + Rational(4027, 4))**Rational(1, 3)) + Rational(20, 3)) def test_issue_10397(): assert solveset(sqrt(x), x, S.Complexes) == FiniteSet(0) def test_issue_14987(): raises(ValueError, lambda: linear_eq_to_matrix( [x**2], x)) raises(ValueError, lambda: linear_eq_to_matrix( [x*(-3/x + 1) + 2*y - a], [x, y])) raises(ValueError, lambda: linear_eq_to_matrix( [(x**2 - 3*x)/(x - 3) - 3], x)) raises(ValueError, lambda: linear_eq_to_matrix( [(x + 1)**3 - x**3 - 3*x**2 + 7], x)) raises(ValueError, lambda: linear_eq_to_matrix( [x*(1/x + 1) + y], [x, y])) raises(ValueError, lambda: linear_eq_to_matrix( [(x + 1)*y], [x, y])) raises(ValueError, lambda: linear_eq_to_matrix( [Eq(1/x, 1/x + y)], [x, y])) raises(ValueError, lambda: linear_eq_to_matrix( [Eq(y/x, y/x + y)], [x, y])) raises(ValueError, lambda: linear_eq_to_matrix( [Eq(x*(x + 1), x**2 + y)], [x, y])) def test_simplification(): eq = x + (a - b)/(-2*a + 2*b) assert solveset(eq, x) == FiniteSet(S.Half) assert solveset(eq, x, S.Reals) == Intersection({-((a - b)/(-2*a + 2*b))}, S.Reals) # So that ap - bn is not zero: ap = Symbol('ap', positive=True) bn = Symbol('bn', negative=True) eq = x + (ap - bn)/(-2*ap + 2*bn) assert solveset(eq, x) == FiniteSet(S.Half) assert solveset(eq, x, S.Reals) == FiniteSet(S.Half) def test_integer_domain_relational(): eq1 = 2*x + 3 > 0 eq2 = x**2 + 3*x - 2 >= 0 eq3 = x + 1/x > -2 + 1/x eq4 = x + sqrt(x**2 - 5) > 0 eq = x + 1/x > -2 + 1/x eq5 = eq.subs(x,log(x)) eq6 = log(x)/x <= 0 eq7 = log(x)/x < 0 eq8 = x/(x-3) < 3 eq9 = x/(x**2-3) < 3 assert solveset(eq1, x, S.Integers) == Range(-1, oo, 1) assert solveset(eq2, x, S.Integers) == Union(Range(-oo, -3, 1), Range(1, oo, 1)) assert solveset(eq3, x, S.Integers) == Union(Range(-1, 0, 1), Range(1, oo, 1)) assert solveset(eq4, x, S.Integers) == Range(3, oo, 1) assert solveset(eq5, x, S.Integers) == Range(2, oo, 1) assert solveset(eq6, x, S.Integers) == Range(1, 2, 1) assert solveset(eq7, x, S.Integers) == S.EmptySet assert solveset(eq8, x, domain=Range(0,5)) == Range(0, 3, 1) assert solveset(eq9, x, domain=Range(0,5)) == Union(Range(0, 2, 1), Range(2, 5, 1)) # test_issue_19794 assert solveset(x + 2 < 0, x, S.Integers) == Range(-oo, -2, 1) def test_issue_10555(): f = Function('f') g = Function('g') assert solveset(f(x) - pi/2, x, S.Reals).dummy_eq( ConditionSet(x, Eq(f(x) - pi/2, 0), S.Reals)) assert solveset(f(g(x)) - pi/2, g(x), S.Reals).dummy_eq( ConditionSet(g(x), Eq(f(g(x)) - pi/2, 0), S.Reals)) def test_issue_8715(): eq = x + 1/x > -2 + 1/x assert solveset(eq, x, S.Reals) == \ (Interval.open(-2, oo) - FiniteSet(0)) assert solveset(eq.subs(x,log(x)), x, S.Reals) == \ Interval.open(exp(-2), oo) - FiniteSet(1) def test_issue_11174(): eq = z**2 + exp(2*x) - sin(y) soln = Intersection(S.Reals, FiniteSet(log(-z**2 + sin(y))/2)) assert solveset(eq, x, S.Reals) == soln eq = sqrt(r)*Abs(tan(t))/sqrt(tan(t)**2 + 1) + x*tan(t) s = -sqrt(r)*Abs(tan(t))/(sqrt(tan(t)**2 + 1)*tan(t)) soln = Intersection(S.Reals, FiniteSet(s)) assert solveset(eq, x, S.Reals) == soln def test_issue_11534(): # eq and eq2 should give the same solution as a Complement x = Symbol('x', real=True) y = Symbol('y', real=True) eq = -y + x/sqrt(-x**2 + 1) eq2 = -y**2 + x**2/(-x**2 + 1) soln = Complement(FiniteSet(-y/sqrt(y**2 + 1), y/sqrt(y**2 + 1)), FiniteSet(-1, 1)) assert solveset(eq, x, S.Reals) == soln assert solveset(eq2, x, S.Reals) == soln def test_issue_10477(): assert solveset((x**2 + 4*x - 3)/x < 2, x, S.Reals) == \ Union(Interval.open(-oo, -3), Interval.open(0, 1)) def test_issue_10671(): assert solveset(sin(y), y, Interval(0, pi)) == FiniteSet(0, pi) i = Interval(1, 10) assert solveset((1/x).diff(x) < 0, x, i) == i def test_issue_11064(): eq = x + sqrt(x**2 - 5) assert solveset(eq > 0, x, S.Reals) == \ Interval(sqrt(5), oo) assert solveset(eq < 0, x, S.Reals) == \ Interval(-oo, -sqrt(5)) assert solveset(eq > sqrt(5), x, S.Reals) == \ Interval.Lopen(sqrt(5), oo) def test_issue_12478(): eq = sqrt(x - 2) + 2 soln = solveset_real(eq, x) assert soln is S.EmptySet assert solveset(eq < 0, x, S.Reals) is S.EmptySet assert solveset(eq > 0, x, S.Reals) == Interval(2, oo) def test_issue_12429(): eq = solveset(log(x)/x <= 0, x, S.Reals) sol = Interval.Lopen(0, 1) assert eq == sol def test_solveset_arg(): assert solveset(arg(x), x, S.Reals) == Interval.open(0, oo) assert solveset(arg(4*x -3), x) == Interval.open(Rational(3, 4), oo) def test__is_finite_with_finite_vars(): f = _is_finite_with_finite_vars # issue 12482 assert all(f(1/x) is None for x in ( Dummy(), Dummy(real=True), Dummy(complex=True))) assert f(1/Dummy(real=False)) is True # b/c it's finite but not 0 def test_issue_13550(): assert solveset(x**2 - 2*x - 15, symbol = x, domain = Interval(-oo, 0)) == FiniteSet(-3) def test_issue_13849(): assert nonlinsolve((t*(sqrt(5) + sqrt(2)) - sqrt(2), t), t) == EmptySet() def test_issue_14223(): assert solveset((Abs(x + Min(x, 2)) - 2).rewrite(Piecewise), x, S.Reals) == FiniteSet(-1, 1) assert solveset((Abs(x + Min(x, 2)) - 2).rewrite(Piecewise), x, Interval(0, 2)) == FiniteSet(1) def test_issue_10158(): dom = S.Reals assert solveset(x*Max(x, 15) - 10, x, dom) == FiniteSet(Rational(2, 3)) assert solveset(x*Min(x, 15) - 10, x, dom) == FiniteSet(-sqrt(10), sqrt(10)) assert solveset(Max(Abs(x - 3) - 1, x + 2) - 3, x, dom) == FiniteSet(-1, 1) assert solveset(Abs(x - 1) - Abs(y), x, dom) == FiniteSet(-Abs(y) + 1, Abs(y) + 1) assert solveset(Abs(x + 4*Abs(x + 1)), x, dom) == FiniteSet(Rational(-4, 3), Rational(-4, 5)) assert solveset(2*Abs(x + Abs(x + Max(3, x))) - 2, x, S.Reals) == FiniteSet(-1, -2) dom = S.Complexes raises(ValueError, lambda: solveset(x*Max(x, 15) - 10, x, dom)) raises(ValueError, lambda: solveset(x*Min(x, 15) - 10, x, dom)) raises(ValueError, lambda: solveset(Max(Abs(x - 3) - 1, x + 2) - 3, x, dom)) raises(ValueError, lambda: solveset(Abs(x - 1) - Abs(y), x, dom)) raises(ValueError, lambda: solveset(Abs(x + 4*Abs(x + 1)), x, dom)) def test_issue_14300(): f = 1 - exp(-18000000*x) - y a1 = FiniteSet(-log(-y + 1)/18000000) assert solveset(f, x, S.Reals) == \ Intersection(S.Reals, a1) assert dumeq(solveset(f, x), ImageSet(Lambda(n, -I*(2*n*pi + arg(-y + 1))/18000000 - log(Abs(y - 1))/18000000), S.Integers)) def test_issue_14454(): number = CRootOf(x**4 + x - 1, 2) raises(ValueError, lambda: invert_real(number, 0, x, S.Reals)) assert invert_real(x**2, number, x, S.Reals) # no error def test_issue_17882(): assert solveset(-8*x**2/(9*(x**2 - 1)**(S(4)/3)) + 4/(3*(x**2 - 1)**(S(1)/3)), x, S.Complexes) == \ FiniteSet(sqrt(3), -sqrt(3)) def test_term_factors(): assert list(_term_factors(3**x - 2)) == [-2, 3**x] expr = 4**(x + 1) + 4**(x + 2) + 4**(x - 1) - 3**(x + 2) - 3**(x + 3) assert set(_term_factors(expr)) == { 3**(x + 2), 4**(x + 2), 3**(x + 3), 4**(x - 1), -1, 4**(x + 1)} #################### tests for transolve and its helpers ############### def test_transolve(): assert _transolve(3**x, x, S.Reals) == S.EmptySet assert _transolve(3**x - 9**(x + 5), x, S.Reals) == FiniteSet(-10) def test_issue_21276(): eq = (2*x*(y - z) - y*erf(y - z) - y + z*erf(y - z) + z)**2 assert solveset(eq.expand(), y) == FiniteSet(z, z + erfinv(2*x - 1)) # exponential tests def test_exponential_real(): from sympy.abc import x, y, z e1 = 3**(2*x) - 2**(x + 3) e2 = 4**(5 - 9*x) - 8**(2 - x) e3 = 2**x + 4**x e4 = exp(log(5)*x) - 2**x e5 = exp(x/y)*exp(-z/y) - 2 e6 = 5**(x/2) - 2**(x/3) e7 = 4**(x + 1) + 4**(x + 2) + 4**(x - 1) - 3**(x + 2) - 3**(x + 3) e8 = -9*exp(-2*x + 5) + 4*exp(3*x + 1) e9 = 2**x + 4**x + 8**x - 84 e10 = 29*2**(x + 1)*615**(x) - 123*2726**(x) assert solveset(e1, x, S.Reals) == FiniteSet( -3*log(2)/(-2*log(3) + log(2))) assert solveset(e2, x, S.Reals) == FiniteSet(Rational(4, 15)) assert solveset(e3, x, S.Reals) == S.EmptySet assert solveset(e4, x, S.Reals) == FiniteSet(0) assert solveset(e5, x, S.Reals) == Intersection( S.Reals, FiniteSet(y*log(2*exp(z/y)))) assert solveset(e6, x, S.Reals) == FiniteSet(0) assert solveset(e7, x, S.Reals) == FiniteSet(2) assert solveset(e8, x, S.Reals) == FiniteSet(-2*log(2)/5 + 2*log(3)/5 + Rational(4, 5)) assert solveset(e9, x, S.Reals) == FiniteSet(2) assert solveset(e10,x, S.Reals) == FiniteSet((-log(29) - log(2) + log(123))/(-log(2726) + log(2) + log(615))) assert solveset_real(-9*exp(-2*x + 5) + 2**(x + 1), x) == FiniteSet( -((-5 - 2*log(3) + log(2))/(log(2) + 2))) assert solveset_real(4**(x/2) - 2**(x/3), x) == FiniteSet(0) b = sqrt(6)*sqrt(log(2))/sqrt(log(5)) assert solveset_real(5**(x/2) - 2**(3/x), x) == FiniteSet(-b, b) # coverage test C1, C2 = symbols('C1 C2') f = Function('f') assert solveset_real(C1 + C2/x**2 - exp(-f(x)), f(x)) == Intersection( S.Reals, FiniteSet(-log(C1 + C2/x**2))) y = symbols('y', positive=True) assert solveset_real(x**2 - y**2/exp(x), y) == Intersection( S.Reals, FiniteSet(-sqrt(x**2*exp(x)), sqrt(x**2*exp(x)))) p = Symbol('p', positive=True) assert solveset_real((1/p + 1)**(p + 1), p).dummy_eq( ConditionSet(x, Eq((1 + 1/x)**(x + 1), 0), S.Reals)) @XFAIL def test_exponential_complex(): from sympy.abc import x from sympy import Dummy n = Dummy('n') assert dumeq(solveset_complex(2**x + 4**x, x),imageset( Lambda(n, I*(2*n*pi + pi)/log(2)), S.Integers)) assert solveset_complex(x**z*y**z - 2, z) == FiniteSet( log(2)/(log(x) + log(y))) assert dumeq(solveset_complex(4**(x/2) - 2**(x/3), x), imageset( Lambda(n, 3*n*I*pi/log(2)), S.Integers)) assert dumeq(solveset(2**x + 32, x), imageset( Lambda(n, (I*(2*n*pi + pi) + 5*log(2))/log(2)), S.Integers)) eq = (2**exp(y**2/x) + 2)/(x**2 + 15) a = sqrt(x)*sqrt(-log(log(2)) + log(log(2) + 2*n*I*pi)) assert solveset_complex(eq, y) == FiniteSet(-a, a) union1 = imageset(Lambda(n, I*(2*n*pi - pi*Rational(2, 3))/log(2)), S.Integers) union2 = imageset(Lambda(n, I*(2*n*pi + pi*Rational(2, 3))/log(2)), S.Integers) assert dumeq(solveset(2**x + 4**x + 8**x, x), Union(union1, union2)) eq = 4**(x + 1) + 4**(x + 2) + 4**(x - 1) - 3**(x + 2) - 3**(x + 3) res = solveset(eq, x) num = 2*n*I*pi - 4*log(2) + 2*log(3) den = -2*log(2) + log(3) ans = imageset(Lambda(n, num/den), S.Integers) assert dumeq(res, ans) def test_expo_conditionset(): f1 = (exp(x) + 1)**x - 2 f2 = (x + 2)**y*x - 3 f3 = 2**x - exp(x) - 3 f4 = log(x) - exp(x) f5 = 2**x + 3**x - 5**x assert solveset(f1, x, S.Reals).dummy_eq(ConditionSet( x, Eq((exp(x) + 1)**x - 2, 0), S.Reals)) assert solveset(f2, x, S.Reals).dummy_eq(ConditionSet( x, Eq(x*(x + 2)**y - 3, 0), S.Reals)) assert solveset(f3, x, S.Reals).dummy_eq(ConditionSet( x, Eq(2**x - exp(x) - 3, 0), S.Reals)) assert solveset(f4, x, S.Reals).dummy_eq(ConditionSet( x, Eq(-exp(x) + log(x), 0), S.Reals)) assert solveset(f5, x, S.Reals).dummy_eq(ConditionSet( x, Eq(2**x + 3**x - 5**x, 0), S.Reals)) def test_exponential_symbols(): x, y, z = symbols('x y z', positive=True) xr, zr = symbols('xr, zr', real=True) assert solveset(z**x - y, x, S.Reals) == Intersection( S.Reals, FiniteSet(log(y)/log(z))) f1 = 2*x**w - 4*y**w f2 = (x/y)**w - 2 sol1 = Intersection({log(2)/(log(x) - log(y))}, S.Reals) sol2 = Intersection({log(2)/log(x/y)}, S.Reals) assert solveset(f1, w, S.Reals) == sol1, solveset(f1, w, S.Reals) assert solveset(f2, w, S.Reals) == sol2, solveset(f2, w, S.Reals) assert solveset(x**x, x, Interval.Lopen(0,oo)).dummy_eq( ConditionSet(w, Eq(w**w, 0), Interval.open(0, oo))) assert solveset(x**y - 1, y, S.Reals) == FiniteSet(0) assert solveset(exp(x/y)*exp(-z/y) - 2, y, S.Reals) == \ Complement(ConditionSet(y, Eq(im(x)/y, 0) & Eq(im(z)/y, 0), \ Complement(Intersection(FiniteSet((x - z)/log(2)), S.Reals), FiniteSet(0))), FiniteSet(0)) assert solveset(exp(xr/y)*exp(-zr/y) - 2, y, S.Reals) == \ Complement(FiniteSet((xr - zr)/log(2)), FiniteSet(0)) assert solveset(a**x - b**x, x).dummy_eq(ConditionSet( w, Ne(a, 0) & Ne(b, 0), FiniteSet(0))) def test_ignore_assumptions(): # make sure assumptions are ignored xpos = symbols('x', positive=True) x = symbols('x') assert solveset_complex(xpos**2 - 4, xpos ) == solveset_complex(x**2 - 4, x) @XFAIL def test_issue_10864(): assert solveset(x**(y*z) - x, x, S.Reals) == FiniteSet(1) @XFAIL def test_solve_only_exp_2(): assert solveset_real(sqrt(exp(x)) + sqrt(exp(-x)) - 4, x) == \ FiniteSet(2*log(-sqrt(3) + 2), 2*log(sqrt(3) + 2)) def test_is_exponential(): assert _is_exponential(y, x) is False assert _is_exponential(3**x - 2, x) is True assert _is_exponential(5**x - 7**(2 - x), x) is True assert _is_exponential(sin(2**x) - 4*x, x) is False assert _is_exponential(x**y - z, y) is True assert _is_exponential(x**y - z, x) is False assert _is_exponential(2**x + 4**x - 1, x) is True assert _is_exponential(x**(y*z) - x, x) is False assert _is_exponential(x**(2*x) - 3**x, x) is False assert _is_exponential(x**y - y*z, y) is False assert _is_exponential(x**y - x*z, y) is True def test_solve_exponential(): assert _solve_exponential(3**(2*x) - 2**(x + 3), 0, x, S.Reals) == \ FiniteSet(-3*log(2)/(-2*log(3) + log(2))) assert _solve_exponential(2**y + 4**y, 1, y, S.Reals) == \ FiniteSet(log(Rational(-1, 2) + sqrt(5)/2)/log(2)) assert _solve_exponential(2**y + 4**y, 0, y, S.Reals) == \ S.EmptySet assert _solve_exponential(2**x + 3**x - 5**x, 0, x, S.Reals) == \ ConditionSet(x, Eq(2**x + 3**x - 5**x, 0), S.Reals) # end of exponential tests # logarithmic tests def test_logarithmic(): assert solveset_real(log(x - 3) + log(x + 3), x) == FiniteSet( -sqrt(10), sqrt(10)) assert solveset_real(log(x + 1) - log(2*x - 1), x) == FiniteSet(2) assert solveset_real(log(x + 3) + log(1 + 3/x) - 3, x) == FiniteSet( -3 + sqrt(-12 + exp(3))*exp(Rational(3, 2))/2 + exp(3)/2, -sqrt(-12 + exp(3))*exp(Rational(3, 2))/2 - 3 + exp(3)/2) eq = z - log(x) + log(y/(x*(-1 + y**2/x**2))) assert solveset_real(eq, x) == \ Intersection(S.Reals, FiniteSet(-sqrt(y**2 - y*exp(z)), sqrt(y**2 - y*exp(z)))) - \ Intersection(S.Reals, FiniteSet(-sqrt(y**2), sqrt(y**2))) assert solveset_real( log(3*x) - log(-x + 1) - log(4*x + 1), x) == FiniteSet(Rational(-1, 2), S.Half) assert solveset(log(x**y) - y*log(x), x, S.Reals) == S.Reals @XFAIL def test_uselogcombine_2(): eq = log(exp(2*x) + 1) + log(-tanh(x) + 1) - log(2) assert solveset_real(eq, x) == EmptySet() eq = log(8*x) - log(sqrt(x) + 1) - 2 assert solveset_real(eq, x) == EmptySet() def test_is_logarithmic(): assert _is_logarithmic(y, x) is False assert _is_logarithmic(log(x), x) is True assert _is_logarithmic(log(x) - 3, x) is True assert _is_logarithmic(log(x)*log(y), x) is True assert _is_logarithmic(log(x)**2, x) is False assert _is_logarithmic(log(x - 3) + log(x + 3), x) is True assert _is_logarithmic(log(x**y) - y*log(x), x) is True assert _is_logarithmic(sin(log(x)), x) is False assert _is_logarithmic(x + y, x) is False assert _is_logarithmic(log(3*x) - log(1 - x) + 4, x) is True assert _is_logarithmic(log(x) + log(y) + x, x) is False assert _is_logarithmic(log(log(x - 3)) + log(x - 3), x) is True assert _is_logarithmic(log(log(3) + x) + log(x), x) is True assert _is_logarithmic(log(x)*(y + 3) + log(x), y) is False def test_solve_logarithm(): y = Symbol('y') assert _solve_logarithm(log(x**y) - y*log(x), 0, x, S.Reals) == S.Reals y = Symbol('y', positive=True) assert _solve_logarithm(log(x)*log(y), 0, x, S.Reals) == FiniteSet(1) # end of logarithmic tests # lambert tests def test_is_lambert(): a, b, c = symbols('a,b,c') assert _is_lambert(x**2, x) is False assert _is_lambert(a**x**2+b*x+c, x) is True assert _is_lambert(E**2, x) is False assert _is_lambert(x*E**2, x) is False assert _is_lambert(3*log(x) - x*log(3), x) is True assert _is_lambert(log(log(x - 3)) + log(x-3), x) is True assert _is_lambert(5*x - 1 + 3*exp(2 - 7*x), x) is True assert _is_lambert((a/x + exp(x/2)).diff(x, 2), x) is True assert _is_lambert((x**2 - 2*x + 1).subs(x, (log(x) + 3*x)**2 - 1), x) is True assert _is_lambert(x*sinh(x) - 1, x) is True assert _is_lambert(x*cos(x) - 5, x) is True assert _is_lambert(tanh(x) - 5*x, x) is True assert _is_lambert(cosh(x) - sinh(x), x) is False # end of lambert tests def test_linear_coeffs(): from sympy.solvers.solveset import linear_coeffs assert linear_coeffs(0, x) == [0, 0] assert all(i is S.Zero for i in linear_coeffs(0, x)) assert linear_coeffs(x + 2*y + 3, x, y) == [1, 2, 3] assert linear_coeffs(x + 2*y + 3, y, x) == [2, 1, 3] assert linear_coeffs(x + 2*x**2 + 3, x, x**2) == [1, 2, 3] raises(ValueError, lambda: linear_coeffs(x + 2*x**2 + x**3, x, x**2)) raises(ValueError, lambda: linear_coeffs(1/x*(x - 1) + 1/x, x)) assert linear_coeffs(a*(x + y), x, y) == [a, a, 0] assert linear_coeffs(1.0, x, y) == [0, 0, 1.0] # modular tests def test_is_modular(): assert _is_modular(y, x) is False assert _is_modular(Mod(x, 3) - 1, x) is True assert _is_modular(Mod(x**3 - 3*x**2 - x + 1, 3) - 1, x) is True assert _is_modular(Mod(exp(x + y), 3) - 2, x) is True assert _is_modular(Mod(exp(x + y), 3) - log(x), x) is True assert _is_modular(Mod(x, 3) - 1, y) is False assert _is_modular(Mod(x, 3)**2 - 5, x) is False assert _is_modular(Mod(x, 3)**2 - y, x) is False assert _is_modular(exp(Mod(x, 3)) - 1, x) is False assert _is_modular(Mod(3, y) - 1, y) is False def test_invert_modular(): n = Dummy('n', integer=True) from sympy.solvers.solveset import _invert_modular as invert_modular # non invertible cases assert invert_modular(Mod(sin(x), 7), S(5), n, x) == (Mod(sin(x), 7), 5) assert invert_modular(Mod(exp(x), 7), S(5), n, x) == (Mod(exp(x), 7), 5) assert invert_modular(Mod(log(x), 7), S(5), n, x) == (Mod(log(x), 7), 5) # a is symbol assert dumeq(invert_modular(Mod(x, 7), S(5), n, x), (x, ImageSet(Lambda(n, 7*n + 5), S.Integers))) # a.is_Add assert dumeq(invert_modular(Mod(x + 8, 7), S(5), n, x), (x, ImageSet(Lambda(n, 7*n + 4), S.Integers))) assert invert_modular(Mod(x**2 + x, 7), S(5), n, x) == \ (Mod(x**2 + x, 7), 5) # a.is_Mul assert dumeq(invert_modular(Mod(3*x, 7), S(5), n, x), (x, ImageSet(Lambda(n, 7*n + 4), S.Integers))) assert invert_modular(Mod((x + 1)*(x + 2), 7), S(5), n, x) == \ (Mod((x + 1)*(x + 2), 7), 5) # a.is_Pow assert invert_modular(Mod(x**4, 7), S(5), n, x) == \ (x, EmptySet()) assert dumeq(invert_modular(Mod(3**x, 4), S(3), n, x), (x, ImageSet(Lambda(n, 2*n + 1), S.Naturals0))) assert dumeq(invert_modular(Mod(2**(x**2 + x + 1), 7), S(2), n, x), (x**2 + x + 1, ImageSet(Lambda(n, 3*n + 1), S.Naturals0))) assert invert_modular(Mod(sin(x)**4, 7), S(5), n, x) == (x, EmptySet()) def test_solve_modular(): n = Dummy('n', integer=True) # if rhs has symbol (need to be implemented in future). assert solveset(Mod(x, 4) - x, x, S.Integers ).dummy_eq( ConditionSet(x, Eq(-x + Mod(x, 4), 0), S.Integers)) # when _invert_modular fails to invert assert solveset(3 - Mod(sin(x), 7), x, S.Integers ).dummy_eq( ConditionSet(x, Eq(Mod(sin(x), 7) - 3, 0), S.Integers)) assert solveset(3 - Mod(log(x), 7), x, S.Integers ).dummy_eq( ConditionSet(x, Eq(Mod(log(x), 7) - 3, 0), S.Integers)) assert solveset(3 - Mod(exp(x), 7), x, S.Integers ).dummy_eq(ConditionSet(x, Eq(Mod(exp(x), 7) - 3, 0), S.Integers)) # EmptySet solution definitely assert solveset(7 - Mod(x, 5), x, S.Integers) == EmptySet() assert solveset(5 - Mod(x, 5), x, S.Integers) == EmptySet() # Negative m assert dumeq(solveset(2 + Mod(x, -3), x, S.Integers), ImageSet(Lambda(n, -3*n - 2), S.Integers)) assert solveset(4 + Mod(x, -3), x, S.Integers) == EmptySet() # linear expression in Mod assert dumeq(solveset(3 - Mod(x, 5), x, S.Integers), ImageSet(Lambda(n, 5*n + 3), S.Integers)) assert dumeq(solveset(3 - Mod(5*x - 8, 7), x, S.Integers), ImageSet(Lambda(n, 7*n + 5), S.Integers)) assert dumeq(solveset(3 - Mod(5*x, 7), x, S.Integers), ImageSet(Lambda(n, 7*n + 2), S.Integers)) # higher degree expression in Mod assert dumeq(solveset(Mod(x**2, 160) - 9, x, S.Integers), Union(ImageSet(Lambda(n, 160*n + 3), S.Integers), ImageSet(Lambda(n, 160*n + 13), S.Integers), ImageSet(Lambda(n, 160*n + 67), S.Integers), ImageSet(Lambda(n, 160*n + 77), S.Integers), ImageSet(Lambda(n, 160*n + 83), S.Integers), ImageSet(Lambda(n, 160*n + 93), S.Integers), ImageSet(Lambda(n, 160*n + 147), S.Integers), ImageSet(Lambda(n, 160*n + 157), S.Integers))) assert solveset(3 - Mod(x**4, 7), x, S.Integers) == EmptySet() assert dumeq(solveset(Mod(x**4, 17) - 13, x, S.Integers), Union(ImageSet(Lambda(n, 17*n + 3), S.Integers), ImageSet(Lambda(n, 17*n + 5), S.Integers), ImageSet(Lambda(n, 17*n + 12), S.Integers), ImageSet(Lambda(n, 17*n + 14), S.Integers))) # a.is_Pow tests assert dumeq(solveset(Mod(7**x, 41) - 15, x, S.Integers), ImageSet(Lambda(n, 40*n + 3), S.Naturals0)) assert dumeq(solveset(Mod(12**x, 21) - 18, x, S.Integers), ImageSet(Lambda(n, 6*n + 2), S.Naturals0)) assert dumeq(solveset(Mod(3**x, 4) - 3, x, S.Integers), ImageSet(Lambda(n, 2*n + 1), S.Naturals0)) assert dumeq(solveset(Mod(2**x, 7) - 2 , x, S.Integers), ImageSet(Lambda(n, 3*n + 1), S.Naturals0)) assert dumeq(solveset(Mod(3**(3**x), 4) - 3, x, S.Integers), Intersection(ImageSet(Lambda(n, Intersection({log(2*n + 1)/log(3)}, S.Integers)), S.Naturals0), S.Integers)) # Implemented for m without primitive root assert solveset(Mod(x**3, 7) - 2, x, S.Integers) == EmptySet() assert dumeq(solveset(Mod(x**3, 8) - 1, x, S.Integers), ImageSet(Lambda(n, 8*n + 1), S.Integers)) assert dumeq(solveset(Mod(x**4, 9) - 4, x, S.Integers), Union(ImageSet(Lambda(n, 9*n + 4), S.Integers), ImageSet(Lambda(n, 9*n + 5), S.Integers))) # domain intersection assert dumeq(solveset(3 - Mod(5*x - 8, 7), x, S.Naturals0), Intersection(ImageSet(Lambda(n, 7*n + 5), S.Integers), S.Naturals0)) # Complex args assert solveset(Mod(x, 3) - I, x, S.Integers) == \ EmptySet() assert solveset(Mod(I*x, 3) - 2, x, S.Integers ).dummy_eq( ConditionSet(x, Eq(Mod(I*x, 3) - 2, 0), S.Integers)) assert solveset(Mod(I + x, 3) - 2, x, S.Integers ).dummy_eq( ConditionSet(x, Eq(Mod(x + I, 3) - 2, 0), S.Integers)) # issue 17373 (https://github.com/sympy/sympy/issues/17373) assert dumeq(solveset(Mod(x**4, 14) - 11, x, S.Integers), Union(ImageSet(Lambda(n, 14*n + 3), S.Integers), ImageSet(Lambda(n, 14*n + 11), S.Integers))) assert dumeq(solveset(Mod(x**31, 74) - 43, x, S.Integers), ImageSet(Lambda(n, 74*n + 31), S.Integers)) # issue 13178 n = symbols('n', integer=True) a = 742938285 b = 1898888478 m = 2**31 - 1 c = 20170816 assert dumeq(solveset(c - Mod(a**n*b, m), n, S.Integers), ImageSet(Lambda(n, 2147483646*n + 100), S.Naturals0)) assert dumeq(solveset(c - Mod(a**n*b, m), n, S.Naturals0), Intersection(ImageSet(Lambda(n, 2147483646*n + 100), S.Naturals0), S.Naturals0)) assert dumeq(solveset(c - Mod(a**(2*n)*b, m), n, S.Integers), Intersection(ImageSet(Lambda(n, 1073741823*n + 50), S.Naturals0), S.Integers)) assert solveset(c - Mod(a**(2*n + 7)*b, m), n, S.Integers) == EmptySet() assert dumeq(solveset(c - Mod(a**(n - 4)*b, m), n, S.Integers), Intersection(ImageSet(Lambda(n, 2147483646*n + 104), S.Naturals0), S.Integers)) # end of modular tests def test_issue_17276(): assert nonlinsolve([Eq(x, 5**(S(1)/5)), Eq(x*y, 25*sqrt(5))], x, y) == \ FiniteSet((5**(S(1)/5), 25*5**(S(3)/10))) def test_issue_10426(): x = Dummy('x') a = Symbol('a') n = Dummy('n') assert (solveset(sin(x + a) - sin(x), a)).dummy_eq(Dummy('x')) == (Union( ImageSet(Lambda(n, 2*n*pi), S.Integers), Intersection(S.Complexes, ImageSet(Lambda(n, -I*(I*(2*n*pi + arg(-exp(-2*I*x))) + 2*im(x))), S.Integers)))).dummy_eq(Dummy('x,n')) def test_issue_18208(): vars = symbols('x0:16') + symbols('y0:12') x0, x1, x2, x3, x4, x5, x6, x7, x8, x9, x10, x11, x12, x13, x14, x15,\ y0, y1, y2, y3, y4, y5, y6, y7, y8, y9, y10, y11 = vars eqs = [x0 + x1 + x2 + x3 - 51, x0 + x1 + x4 + x5 - 46, x2 + x3 + x6 + x7 - 39, x0 + x3 + x4 + x7 - 50, x1 + x2 + x5 + x6 - 35, x4 + x5 + x6 + x7 - 34, x4 + x5 + x8 + x9 - 46, x10 + x11 + x6 + x7 - 23, x11 + x4 + x7 + x8 - 25, x10 + x5 + x6 + x9 - 44, x10 + x11 + x8 + x9 - 35, x12 + x13 + x8 + x9 - 35, x10 + x11 + x14 + x15 - 29, x11 + x12 + x15 + x8 - 35, x10 + x13 + x14 + x9 - 29, x12 + x13 + x14 + x15 - 29, y0 + y1 + y2 + y3 - 55, y0 + y1 + y4 + y5 - 53, y2 + y3 + y6 + y7 - 56, y0 + y3 + y4 + y7 - 57, y1 + y2 + y5 + y6 - 52, y4 + y5 + y6 + y7 - 54, y4 + y5 + y8 + y9 - 48, y10 + y11 + y6 + y7 - 60, y11 + y4 + y7 + y8 - 51, y10 + y5 + y6 + y9 - 57, y10 + y11 + y8 + y9 - 54, x10 - 2, x11 - 5, x12 - 1, x13 - 6, x14 - 1, x15 - 21, y0 - 12, y1 - 20] expected = [38 - x3, x3 - 10, 23 - x3, x3, 12 - x7, x7 + 6, 16 - x7, x7, 8, 20, 2, 5, 1, 6, 1, 21, 12, 20, -y11 + y9 + 2, y11 - y9 + 21, -y11 - y7 + y9 + 24, y11 + y7 - y9 - 3, 33 - y7, y7, 27 - y9, y9, 27 - y11, y11] A, b = linear_eq_to_matrix(eqs, vars) # solve solve_expected = {v:eq for v, eq in zip(vars, expected) if v != eq} assert solve(eqs, vars) == solve_expected # linsolve linsolve_expected = FiniteSet(Tuple(*expected)) assert linsolve(eqs, vars) == linsolve_expected assert linsolve((A, b), vars) == linsolve_expected # gauss_jordan_solve gj_solve, new_vars = A.gauss_jordan_solve(b) gj_solve = [i for i in gj_solve] tau0, tau1, tau2, tau3, tau4 = symbols([str(v) for v in new_vars]) gj_expected = linsolve_expected.subs(zip([x3, x7, y7, y9, y11], new_vars)) assert FiniteSet(Tuple(*gj_solve)) == gj_expected # nonlinsolve # The solution set of nonlinsolve is currently equivalent to linsolve and is # also correct. However, we would prefer to use the same symbols as parameters # for the solution to the underdetermined system in all cases if possible. # We want a solution that is not just equivalent but also given in the same form. # This test may be changed should nonlinsolve be modified in this way. nonlinsolve_expected = FiniteSet((38 - x3, x3 - 10, 23 - x3, x3, 12 - x7, x7 + 6, 16 - x7, x7, 8, 20, 2, 5, 1, 6, 1, 21, 12, 20, -y5 + y7 - 1, y5 - y7 + 24, 21 - y5, y5, 33 - y7, y7, 27 - y9, y9, -y5 + y7 - y9 + 24, y5 - y7 + y9 + 3)) assert nonlinsolve(eqs, vars) == nonlinsolve_expected @XFAIL def test_substitution_with_infeasible_solution(): a00, a01, a10, a11, l0, l1, l2, l3, m0, m1, m2, m3, m4, m5, m6, m7, c00, c01, c10, c11, p00, p01, p10, p11 = symbols( 'a00, a01, a10, a11, l0, l1, l2, l3, m0, m1, m2, m3, m4, m5, m6, m7, c00, c01, c10, c11, p00, p01, p10, p11' ) solvefor = [p00, p01, p10, p11, c00, c01, c10, c11, m0, m1, m3, l0, l1, l2, l3] system = [ -l0 * c00 - l1 * c01 + m0 + c00 + c01, -l0 * c10 - l1 * c11 + m1, -l2 * c00 - l3 * c01 + c00 + c01, -l2 * c10 - l3 * c11 + m3, -l0 * p00 - l2 * p10 + p00 + p10, -l1 * p00 - l3 * p10 + p00 + p10, -l0 * p01 - l2 * p11, -l1 * p01 - l3 * p11, -a00 + c00 * p00 + c10 * p01, -a01 + c01 * p00 + c11 * p01, -a10 + c00 * p10 + c10 * p11, -a11 + c01 * p10 + c11 * p11, -m0 * p00, -m1 * p01, -m2 * p10, -m3 * p11, -m4 * c00, -m5 * c01, -m6 * c10, -m7 * c11, m2, m4, m5, m6, m7 ] sol = FiniteSet( (0, Complement(FiniteSet(p01), FiniteSet(0)), 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, l2, l3), (p00, Complement(FiniteSet(p01), FiniteSet(0)), 0, p11, 0, 0, 0, 0, 0, 0, 0, 1, 1, -p01/p11, -p01/p11), (0, Complement(FiniteSet(p01), FiniteSet(0)), 0, p11, 0, 0, 0, 0, 0, 0, 0, 1, -l3*p11/p01, -p01/p11, l3), (0, Complement(FiniteSet(p01), FiniteSet(0)), 0, p11, 0, 0, 0, 0, 0, 0, 0, -l2*p11/p01, -l3*p11/p01, l2, l3), ) assert sol != nonlinsolve(system, solvefor) def test_issue_21236(): x, z = symbols("x z") y = symbols('y', rational=True) assert solveset(x**y - z, x, S.Reals) == ConditionSet(x, Eq(x**y - z, 0), S.Reals) e1, e2 = symbols('e1 e2', even=True) y = e1/e2 # don't know if num or den will be odd and the other even assert solveset(x**y - z, x, S.Reals) == ConditionSet(x, Eq(x**y - z, 0), S.Reals)
4e2214240b3f99f1941e0e59572550a9b99f97f01e43fdd37e2894f1a2295ada
from sympy import (acosh, cos, Derivative, diff, Eq, exp, Function, I, Integral, log, O, pi, Rational, S, sin, sqrt, Subs, Symbol, tan, symbols, Poly, re, im, atan2, collect) from sympy.solvers.ode import (classify_ode, homogeneous_order, dsolve) from sympy.solvers.ode.subscheck import checkodesol from sympy.solvers.ode.ode import (_undetermined_coefficients_match, classify_sysode, constant_renumber, constantsimp, get_numbered_constants, solve_ics) from sympy.solvers.ode.single import LinearCoefficients from sympy.solvers.deutils import ode_order from sympy.testing.pytest import XFAIL, raises, slow C0, C1, C2, C3, C4, C5, C6, C7, C8, C9, C10 = symbols('C0:11') u, x, y, z = symbols('u,x:z', real=True) f = Function('f') g = Function('g') h = Function('h') # Note: Examples which were specifically testing Single ODE solver are moved to test_single.py # and all the system of ode examples are moved to test_systems.py # Note: the tests below may fail (but still be correct) if ODE solver, # the integral engine, solve(), or even simplify() changes. Also, in # differently formatted solutions, the arbitrary constants might not be # equal. Using specific hints in tests can help to avoid this. # Tests of order higher than 1 should run the solutions through # constant_renumber because it will normalize it (constant_renumber causes # dsolve() to return different results on different machines) def test_get_numbered_constants(): with raises(ValueError): get_numbered_constants(None) def test_dsolve_all_hint(): eq = f(x).diff(x) output = dsolve(eq, hint='all') # Match the Dummy variables: sol1 = output['separable_Integral'] _y = sol1.lhs.args[1][0] sol1 = output['1st_homogeneous_coeff_subs_dep_div_indep_Integral'] _u1 = sol1.rhs.args[1].args[1][0] expected = {'Bernoulli_Integral': Eq(f(x), C1 + Integral(0, x)), '1st_homogeneous_coeff_best': Eq(f(x), C1), 'Bernoulli': Eq(f(x), C1), 'nth_algebraic': Eq(f(x), C1), 'nth_linear_euler_eq_homogeneous': Eq(f(x), C1), 'nth_linear_constant_coeff_homogeneous': Eq(f(x), C1), 'separable': Eq(f(x), C1), '1st_homogeneous_coeff_subs_indep_div_dep': Eq(f(x), C1), 'nth_algebraic_Integral': Eq(f(x), C1), '1st_linear': Eq(f(x), C1), '1st_linear_Integral': Eq(f(x), C1 + Integral(0, x)), '1st_exact': Eq(f(x), C1), '1st_exact_Integral': Eq(Subs(Integral(0, x) + Integral(1, _y), _y, f(x)), C1), 'lie_group': Eq(f(x), C1), '1st_homogeneous_coeff_subs_dep_div_indep': Eq(f(x), C1), '1st_homogeneous_coeff_subs_dep_div_indep_Integral': Eq(log(x), C1 + Integral(-1/_u1, (_u1, f(x)/x))), '1st_power_series': Eq(f(x), C1), 'separable_Integral': Eq(Integral(1, (_y, f(x))), C1 + Integral(0, x)), '1st_homogeneous_coeff_subs_indep_div_dep_Integral': Eq(f(x), C1), 'best': Eq(f(x), C1), 'best_hint': 'nth_algebraic', 'default': 'nth_algebraic', 'order': 1} assert output == expected assert dsolve(eq, hint='best') == Eq(f(x), C1) def test_dsolve_ics(): # Maybe this should just use one of the solutions instead of raising... with raises(NotImplementedError): dsolve(f(x).diff(x) - sqrt(f(x)), ics={f(1):1}) @slow def test_dsolve_options(): eq = x*f(x).diff(x) + f(x) a = dsolve(eq, hint='all') b = dsolve(eq, hint='all', simplify=False) c = dsolve(eq, hint='all_Integral') keys = ['1st_exact', '1st_exact_Integral', '1st_homogeneous_coeff_best', '1st_homogeneous_coeff_subs_dep_div_indep', '1st_homogeneous_coeff_subs_dep_div_indep_Integral', '1st_homogeneous_coeff_subs_indep_div_dep', '1st_homogeneous_coeff_subs_indep_div_dep_Integral', '1st_linear', '1st_linear_Integral', 'Bernoulli', 'Bernoulli_Integral', 'almost_linear', 'almost_linear_Integral', 'best', 'best_hint', 'default', 'lie_group', 'nth_linear_euler_eq_homogeneous', 'order', 'separable', 'separable_Integral'] Integral_keys = ['1st_exact_Integral', '1st_homogeneous_coeff_subs_dep_div_indep_Integral', '1st_homogeneous_coeff_subs_indep_div_dep_Integral', '1st_linear_Integral', 'Bernoulli_Integral', 'almost_linear_Integral', 'best', 'best_hint', 'default', 'nth_linear_euler_eq_homogeneous', 'order', 'separable_Integral'] assert sorted(a.keys()) == keys assert a['order'] == ode_order(eq, f(x)) assert a['best'] == Eq(f(x), C1/x) assert dsolve(eq, hint='best') == Eq(f(x), C1/x) assert a['default'] == 'separable' assert a['best_hint'] == 'separable' assert not a['1st_exact'].has(Integral) assert not a['separable'].has(Integral) assert not a['1st_homogeneous_coeff_best'].has(Integral) assert not a['1st_homogeneous_coeff_subs_dep_div_indep'].has(Integral) assert not a['1st_homogeneous_coeff_subs_indep_div_dep'].has(Integral) assert not a['1st_linear'].has(Integral) assert a['1st_linear_Integral'].has(Integral) assert a['1st_exact_Integral'].has(Integral) assert a['1st_homogeneous_coeff_subs_dep_div_indep_Integral'].has(Integral) assert a['1st_homogeneous_coeff_subs_indep_div_dep_Integral'].has(Integral) assert a['separable_Integral'].has(Integral) assert sorted(b.keys()) == keys assert b['order'] == ode_order(eq, f(x)) assert b['best'] == Eq(f(x), C1/x) assert dsolve(eq, hint='best', simplify=False) == Eq(f(x), C1/x) assert b['default'] == 'separable' assert b['best_hint'] == '1st_linear' assert a['separable'] != b['separable'] assert a['1st_homogeneous_coeff_subs_dep_div_indep'] != \ b['1st_homogeneous_coeff_subs_dep_div_indep'] assert a['1st_homogeneous_coeff_subs_indep_div_dep'] != \ b['1st_homogeneous_coeff_subs_indep_div_dep'] assert not b['1st_exact'].has(Integral) assert not b['separable'].has(Integral) assert not b['1st_homogeneous_coeff_best'].has(Integral) assert not b['1st_homogeneous_coeff_subs_dep_div_indep'].has(Integral) assert not b['1st_homogeneous_coeff_subs_indep_div_dep'].has(Integral) assert not b['1st_linear'].has(Integral) assert b['1st_linear_Integral'].has(Integral) assert b['1st_exact_Integral'].has(Integral) assert b['1st_homogeneous_coeff_subs_dep_div_indep_Integral'].has(Integral) assert b['1st_homogeneous_coeff_subs_indep_div_dep_Integral'].has(Integral) assert b['separable_Integral'].has(Integral) assert sorted(c.keys()) == Integral_keys raises(ValueError, lambda: dsolve(eq, hint='notarealhint')) raises(ValueError, lambda: dsolve(eq, hint='Liouville')) assert dsolve(f(x).diff(x) - 1/f(x)**2, hint='all')['best'] == \ dsolve(f(x).diff(x) - 1/f(x)**2, hint='best') assert dsolve(f(x) + f(x).diff(x) + sin(x).diff(x) + 1, f(x), hint="1st_linear_Integral") == \ Eq(f(x), (C1 + Integral((-sin(x).diff(x) - 1)* exp(Integral(1, x)), x))*exp(-Integral(1, x))) def test_classify_ode(): assert classify_ode(f(x).diff(x, 2), f(x)) == \ ( 'nth_algebraic', 'nth_linear_constant_coeff_homogeneous', 'nth_linear_euler_eq_homogeneous', 'Liouville', '2nd_power_series_ordinary', 'nth_algebraic_Integral', 'Liouville_Integral', ) assert classify_ode(f(x), f(x)) == ('nth_algebraic', 'nth_algebraic_Integral') assert classify_ode(Eq(f(x).diff(x), 0), f(x)) == ( 'nth_algebraic', 'separable', '1st_exact', '1st_linear', 'Bernoulli', '1st_homogeneous_coeff_best', '1st_homogeneous_coeff_subs_indep_div_dep', '1st_homogeneous_coeff_subs_dep_div_indep', '1st_power_series', 'lie_group', 'nth_linear_constant_coeff_homogeneous', 'nth_linear_euler_eq_homogeneous', 'nth_algebraic_Integral', 'separable_Integral', '1st_exact_Integral', '1st_linear_Integral', 'Bernoulli_Integral', '1st_homogeneous_coeff_subs_indep_div_dep_Integral', '1st_homogeneous_coeff_subs_dep_div_indep_Integral') assert classify_ode(f(x).diff(x)**2, f(x)) == ('factorable', 'nth_algebraic', 'separable', '1st_exact', '1st_linear', 'Bernoulli', '1st_homogeneous_coeff_best', '1st_homogeneous_coeff_subs_indep_div_dep', '1st_homogeneous_coeff_subs_dep_div_indep', '1st_power_series', 'lie_group', 'nth_linear_constant_coeff_homogeneous', 'nth_linear_euler_eq_homogeneous', 'nth_algebraic_Integral', 'separable_Integral', '1st_exact_Integral', '1st_linear_Integral', 'Bernoulli_Integral', '1st_homogeneous_coeff_subs_indep_div_dep_Integral', '1st_homogeneous_coeff_subs_dep_div_indep_Integral') # issue 4749: f(x) should be cleared from highest derivative before classifying a = classify_ode(Eq(f(x).diff(x) + f(x), x), f(x)) b = classify_ode(f(x).diff(x)*f(x) + f(x)*f(x) - x*f(x), f(x)) c = classify_ode(f(x).diff(x)/f(x) + f(x)/f(x) - x/f(x), f(x)) assert a == ('1st_exact', '1st_linear', 'Bernoulli', 'almost_linear', '1st_power_series', "lie_group", 'nth_linear_constant_coeff_undetermined_coefficients', 'nth_linear_constant_coeff_variation_of_parameters', '1st_exact_Integral', '1st_linear_Integral', 'Bernoulli_Integral', 'almost_linear_Integral', 'nth_linear_constant_coeff_variation_of_parameters_Integral') assert b == ('factorable', '1st_linear', 'Bernoulli', '1st_power_series', 'lie_group', 'nth_linear_constant_coeff_undetermined_coefficients', 'nth_linear_constant_coeff_variation_of_parameters', '1st_linear_Integral', 'Bernoulli_Integral', 'nth_linear_constant_coeff_variation_of_parameters_Integral') assert c == ('1st_linear', 'Bernoulli', '1st_power_series', 'lie_group', 'nth_linear_constant_coeff_undetermined_coefficients', 'nth_linear_constant_coeff_variation_of_parameters', '1st_linear_Integral', 'Bernoulli_Integral', 'nth_linear_constant_coeff_variation_of_parameters_Integral') assert classify_ode( 2*x*f(x)*f(x).diff(x) + (1 + x)*f(x)**2 - exp(x), f(x) ) == ('1st_exact', 'Bernoulli', 'almost_linear', 'lie_group', '1st_exact_Integral', 'Bernoulli_Integral', 'almost_linear_Integral') assert 'Riccati_special_minus2' in \ classify_ode(2*f(x).diff(x) + f(x)**2 - f(x)/x + 3*x**(-2), f(x)) raises(ValueError, lambda: classify_ode(x + f(x, y).diff(x).diff( y), f(x, y))) # issue 5176 k = Symbol('k') assert classify_ode(f(x).diff(x)/(k*f(x) + k*x*f(x)) + 2*f(x)/(k*f(x) + k*x*f(x)) + x*f(x).diff(x)/(k*f(x) + k*x*f(x)) + z, f(x)) == \ ('separable', '1st_exact', '1st_linear', 'Bernoulli', '1st_power_series', 'lie_group', 'separable_Integral', '1st_exact_Integral', '1st_linear_Integral', 'Bernoulli_Integral') # preprocessing ans = ('nth_algebraic', 'separable', '1st_exact', '1st_linear', 'Bernoulli', '1st_homogeneous_coeff_best', '1st_homogeneous_coeff_subs_indep_div_dep', '1st_homogeneous_coeff_subs_dep_div_indep', '1st_power_series', 'lie_group', 'nth_linear_constant_coeff_undetermined_coefficients', 'nth_linear_euler_eq_nonhomogeneous_undetermined_coefficients', 'nth_linear_constant_coeff_variation_of_parameters', 'nth_linear_euler_eq_nonhomogeneous_variation_of_parameters', 'nth_algebraic_Integral', 'separable_Integral', '1st_exact_Integral', '1st_linear_Integral', 'Bernoulli_Integral', '1st_homogeneous_coeff_subs_indep_div_dep_Integral', '1st_homogeneous_coeff_subs_dep_div_indep_Integral', 'nth_linear_constant_coeff_variation_of_parameters_Integral', 'nth_linear_euler_eq_nonhomogeneous_variation_of_parameters_Integral') # w/o f(x) given assert classify_ode(diff(f(x) + x, x) + diff(f(x), x)) == ans # w/ f(x) and prep=True assert classify_ode(diff(f(x) + x, x) + diff(f(x), x), f(x), prep=True) == ans assert classify_ode(Eq(2*x**3*f(x).diff(x), 0), f(x)) == \ ('factorable', 'nth_algebraic', 'separable', '1st_exact', '1st_linear', 'Bernoulli', '1st_power_series', 'lie_group', 'nth_linear_euler_eq_homogeneous', 'nth_algebraic_Integral', 'separable_Integral', '1st_exact_Integral', '1st_linear_Integral', 'Bernoulli_Integral') assert classify_ode(Eq(2*f(x)**3*f(x).diff(x), 0), f(x)) == \ ('factorable', 'nth_algebraic', 'separable', '1st_exact', '1st_linear', 'Bernoulli', '1st_power_series', 'lie_group', 'nth_algebraic_Integral', 'separable_Integral', '1st_exact_Integral', '1st_linear_Integral', 'Bernoulli_Integral') # test issue 13864 assert classify_ode(Eq(diff(f(x), x) - f(x)**x, 0), f(x)) == \ ('1st_power_series', 'lie_group') assert isinstance(classify_ode(Eq(f(x), 5), f(x), dict=True), dict) def test_classify_ode_ics(): # Dummy eq = f(x).diff(x, x) - f(x) # Not f(0) or f'(0) ics = {x: 1} raises(ValueError, lambda: classify_ode(eq, f(x), ics=ics)) ############################ # f(0) type (AppliedUndef) # ############################ # Wrong function ics = {g(0): 1} raises(ValueError, lambda: classify_ode(eq, f(x), ics=ics)) # Contains x ics = {f(x): 1} raises(ValueError, lambda: classify_ode(eq, f(x), ics=ics)) # Too many args ics = {f(0, 0): 1} raises(ValueError, lambda: classify_ode(eq, f(x), ics=ics)) # point contains f # XXX: Should be NotImplementedError ics = {f(0): f(1)} raises(ValueError, lambda: classify_ode(eq, f(x), ics=ics)) # Does not raise ics = {f(0): 1} classify_ode(eq, f(x), ics=ics) ##################### # f'(0) type (Subs) # ##################### # Wrong function ics = {g(x).diff(x).subs(x, 0): 1} raises(ValueError, lambda: classify_ode(eq, f(x), ics=ics)) # Contains x ics = {f(y).diff(y).subs(y, x): 1} raises(ValueError, lambda: classify_ode(eq, f(x), ics=ics)) # Wrong variable ics = {f(y).diff(y).subs(y, 0): 1} raises(ValueError, lambda: classify_ode(eq, f(x), ics=ics)) # Too many args ics = {f(x, y).diff(x).subs(x, 0): 1} raises(ValueError, lambda: classify_ode(eq, f(x), ics=ics)) # Derivative wrt wrong vars ics = {Derivative(f(x), x, y).subs(x, 0): 1} raises(ValueError, lambda: classify_ode(eq, f(x), ics=ics)) # point contains f # XXX: Should be NotImplementedError ics = {f(x).diff(x).subs(x, 0): f(0)} raises(ValueError, lambda: classify_ode(eq, f(x), ics=ics)) # Does not raise ics = {f(x).diff(x).subs(x, 0): 1} classify_ode(eq, f(x), ics=ics) ########################### # f'(y) type (Derivative) # ########################### # Wrong function ics = {g(x).diff(x).subs(x, y): 1} raises(ValueError, lambda: classify_ode(eq, f(x), ics=ics)) # Contains x ics = {f(y).diff(y).subs(y, x): 1} raises(ValueError, lambda: classify_ode(eq, f(x), ics=ics)) # Too many args ics = {f(x, y).diff(x).subs(x, y): 1} raises(ValueError, lambda: classify_ode(eq, f(x), ics=ics)) # Derivative wrt wrong vars ics = {Derivative(f(x), x, z).subs(x, y): 1} raises(ValueError, lambda: classify_ode(eq, f(x), ics=ics)) # point contains f # XXX: Should be NotImplementedError ics = {f(x).diff(x).subs(x, y): f(0)} raises(ValueError, lambda: classify_ode(eq, f(x), ics=ics)) # Does not raise ics = {f(x).diff(x).subs(x, y): 1} classify_ode(eq, f(x), ics=ics) def test_classify_sysode(): # Here x is assumed to be x(t) and y as y(t) for simplicity. # Similarly diff(x,t) and diff(y,y) is assumed to be x1 and y1 respectively. k, l, m, n = symbols('k, l, m, n', Integer=True) k1, k2, k3, l1, l2, l3, m1, m2, m3 = symbols('k1, k2, k3, l1, l2, l3, m1, m2, m3', Integer=True) P, Q, R, p, q, r = symbols('P, Q, R, p, q, r', cls=Function) P1, P2, P3, Q1, Q2, R1, R2 = symbols('P1, P2, P3, Q1, Q2, R1, R2', cls=Function) x, y, z = symbols('x, y, z', cls=Function) t = symbols('t') x1 = diff(x(t),t) ; y1 = diff(y(t),t) ; eq6 = (Eq(x1, exp(k*x(t))*P(x(t),y(t))), Eq(y1,r(y(t))*P(x(t),y(t)))) sol6 = {'no_of_equation': 2, 'func_coeff': {(0, x(t), 0): 0, (1, x(t), 1): 0, (0, x(t), 1): 1, (1, y(t), 0): 0, \ (1, x(t), 0): 0, (0, y(t), 1): 0, (0, y(t), 0): 0, (1, y(t), 1): 1}, 'type_of_equation': 'type2', 'func': \ [x(t), y(t)], 'is_linear': False, 'eq': [-P(x(t), y(t))*exp(k*x(t)) + Derivative(x(t), t), -P(x(t), \ y(t))*r(y(t)) + Derivative(y(t), t)], 'order': {y(t): 1, x(t): 1}} assert classify_sysode(eq6) == sol6 eq7 = (Eq(x1, x(t)**2+y(t)/x(t)), Eq(y1, x(t)/y(t))) sol7 = {'no_of_equation': 2, 'func_coeff': {(0, x(t), 0): 0, (1, x(t), 1): 0, (0, x(t), 1): 1, (1, y(t), 0): 0, \ (1, x(t), 0): -1/y(t), (0, y(t), 1): 0, (0, y(t), 0): -1/x(t), (1, y(t), 1): 1}, 'type_of_equation': 'type3', \ 'func': [x(t), y(t)], 'is_linear': False, 'eq': [-x(t)**2 + Derivative(x(t), t) - y(t)/x(t), -x(t)/y(t) + \ Derivative(y(t), t)], 'order': {y(t): 1, x(t): 1}} assert classify_sysode(eq7) == sol7 eq8 = (Eq(x1, P1(x(t))*Q1(y(t))*R(x(t),y(t),t)), Eq(y1, P1(x(t))*Q1(y(t))*R(x(t),y(t),t))) sol8 = {'func': [x(t), y(t)], 'is_linear': False, 'type_of_equation': 'type4', 'eq': \ [-P1(x(t))*Q1(y(t))*R(x(t), y(t), t) + Derivative(x(t), t), -P1(x(t))*Q1(y(t))*R(x(t), y(t), t) + \ Derivative(y(t), t)], 'func_coeff': {(0, y(t), 1): 0, (1, y(t), 1): 1, (1, x(t), 1): 0, (0, y(t), 0): 0, \ (1, x(t), 0): 0, (0, x(t), 0): 0, (1, y(t), 0): 0, (0, x(t), 1): 1}, 'order': {y(t): 1, x(t): 1}, 'no_of_equation': 2} assert classify_sysode(eq8) == sol8 eq11 = (Eq(x1,x(t)*y(t)**3), Eq(y1,y(t)**5)) sol11 = {'no_of_equation': 2, 'func_coeff': {(0, x(t), 0): -y(t)**3, (1, x(t), 1): 0, (0, x(t), 1): 1, \ (1, y(t), 0): 0, (1, x(t), 0): 0, (0, y(t), 1): 0, (0, y(t), 0): 0, (1, y(t), 1): 1}, 'type_of_equation': \ 'type1', 'func': [x(t), y(t)], 'is_linear': False, 'eq': [-x(t)*y(t)**3 + Derivative(x(t), t), \ -y(t)**5 + Derivative(y(t), t)], 'order': {y(t): 1, x(t): 1}} assert classify_sysode(eq11) == sol11 eq13 = (Eq(x1,x(t)*y(t)*sin(t)**2), Eq(y1,y(t)**2*sin(t)**2)) sol13 = {'no_of_equation': 2, 'func_coeff': {(0, x(t), 0): -y(t)*sin(t)**2, (1, x(t), 1): 0, (0, x(t), 1): 1, \ (1, y(t), 0): 0, (1, x(t), 0): 0, (0, y(t), 1): 0, (0, y(t), 0): -x(t)*sin(t)**2, (1, y(t), 1): 1}, \ 'type_of_equation': 'type4', 'func': [x(t), y(t)], 'is_linear': False, 'eq': [-x(t)*y(t)*sin(t)**2 + \ Derivative(x(t), t), -y(t)**2*sin(t)**2 + Derivative(y(t), t)], 'order': {y(t): 1, x(t): 1}} assert classify_sysode(eq13) == sol13 def test_solve_ics(): # Basic tests that things work from dsolve. assert dsolve(f(x).diff(x) - 1/f(x), f(x), ics={f(1): 2}) == \ Eq(f(x), sqrt(2 * x + 2)) assert dsolve(f(x).diff(x) - f(x), f(x), ics={f(0): 1}) == Eq(f(x), exp(x)) assert dsolve(f(x).diff(x) - f(x), f(x), ics={f(x).diff(x).subs(x, 0): 1}) == Eq(f(x), exp(x)) assert dsolve(f(x).diff(x, x) + f(x), f(x), ics={f(0): 1, f(x).diff(x).subs(x, 0): 1}) == Eq(f(x), sin(x) + cos(x)) assert dsolve([f(x).diff(x) - f(x) + g(x), g(x).diff(x) - g(x) - f(x)], [f(x), g(x)], ics={f(0): 1, g(0): 0}) == [Eq(f(x), exp(x)*cos(x)), Eq(g(x), exp(x)*sin(x))] # Test cases where dsolve returns two solutions. eq = (x**2*f(x)**2 - x).diff(x) assert dsolve(eq, f(x), ics={f(1): 0}) == [Eq(f(x), -sqrt(x - 1)/x), Eq(f(x), sqrt(x - 1)/x)] assert dsolve(eq, f(x), ics={f(x).diff(x).subs(x, 1): 0}) == [Eq(f(x), -sqrt(x - S.Half)/x), Eq(f(x), sqrt(x - S.Half)/x)] eq = cos(f(x)) - (x*sin(f(x)) - f(x)**2)*f(x).diff(x) assert dsolve(eq, f(x), ics={f(0):1}, hint='1st_exact', simplify=False) == Eq(x*cos(f(x)) + f(x)**3/3, Rational(1, 3)) assert dsolve(eq, f(x), ics={f(0):1}, hint='1st_exact', simplify=True) == Eq(x*cos(f(x)) + f(x)**3/3, Rational(1, 3)) assert solve_ics([Eq(f(x), C1*exp(x))], [f(x)], [C1], {f(0): 1}) == {C1: 1} assert solve_ics([Eq(f(x), C1*sin(x) + C2*cos(x))], [f(x)], [C1, C2], {f(0): 1, f(pi/2): 1}) == {C1: 1, C2: 1} assert solve_ics([Eq(f(x), C1*sin(x) + C2*cos(x))], [f(x)], [C1, C2], {f(0): 1, f(x).diff(x).subs(x, 0): 1}) == {C1: 1, C2: 1} assert solve_ics([Eq(f(x), C1*sin(x) + C2*cos(x))], [f(x)], [C1, C2], {f(0): 1}) == \ {C2: 1} # Some more complicated tests Refer to PR #16098 assert set(dsolve(f(x).diff(x)*(f(x).diff(x, 2)-x), ics={f(0):0, f(x).diff(x).subs(x, 1):0})) == \ {Eq(f(x), 0), Eq(f(x), x ** 3 / 6 - x / 2)} assert set(dsolve(f(x).diff(x)*(f(x).diff(x, 2)-x), ics={f(0):0})) == \ {Eq(f(x), 0), Eq(f(x), C2*x + x**3/6)} K, r, f0 = symbols('K r f0') sol = Eq(f(x), K*f0*exp(r*x)/((-K + f0)*(f0*exp(r*x)/(-K + f0) - 1))) assert (dsolve(Eq(f(x).diff(x), r * f(x) * (1 - f(x) / K)), f(x), ics={f(0): f0})) == sol #Order dependent issues Refer to PR #16098 assert set(dsolve(f(x).diff(x)*(f(x).diff(x, 2)-x), ics={f(x).diff(x).subs(x,0):0, f(0):0})) == \ {Eq(f(x), 0), Eq(f(x), x ** 3 / 6)} assert set(dsolve(f(x).diff(x)*(f(x).diff(x, 2)-x), ics={f(0):0, f(x).diff(x).subs(x,0):0})) == \ {Eq(f(x), 0), Eq(f(x), x ** 3 / 6)} # XXX: Ought to be ValueError raises(ValueError, lambda: solve_ics([Eq(f(x), C1*sin(x) + C2*cos(x))], [f(x)], [C1, C2], {f(0): 1, f(pi): 1})) # Degenerate case. f'(0) is identically 0. raises(ValueError, lambda: solve_ics([Eq(f(x), sqrt(C1 - x**2))], [f(x)], [C1], {f(x).diff(x).subs(x, 0): 0})) EI, q, L = symbols('EI q L') # eq = Eq(EI*diff(f(x), x, 4), q) sols = [Eq(f(x), C1 + C2*x + C3*x**2 + C4*x**3 + q*x**4/(24*EI))] funcs = [f(x)] constants = [C1, C2, C3, C4] # Test both cases, Derivative (the default from f(x).diff(x).subs(x, L)), # and Subs ics1 = {f(0): 0, f(x).diff(x).subs(x, 0): 0, f(L).diff(L, 2): 0, f(L).diff(L, 3): 0} ics2 = {f(0): 0, f(x).diff(x).subs(x, 0): 0, Subs(f(x).diff(x, 2), x, L): 0, Subs(f(x).diff(x, 3), x, L): 0} solved_constants1 = solve_ics(sols, funcs, constants, ics1) solved_constants2 = solve_ics(sols, funcs, constants, ics2) assert solved_constants1 == solved_constants2 == { C1: 0, C2: 0, C3: L**2*q/(4*EI), C4: -L*q/(6*EI)} def test_ode_order(): f = Function('f') g = Function('g') x = Symbol('x') assert ode_order(3*x*exp(f(x)), f(x)) == 0 assert ode_order(x*diff(f(x), x) + 3*x*f(x) - sin(x)/x, f(x)) == 1 assert ode_order(x**2*f(x).diff(x, x) + x*diff(f(x), x) - f(x), f(x)) == 2 assert ode_order(diff(x*exp(f(x)), x, x), f(x)) == 2 assert ode_order(diff(x*diff(x*exp(f(x)), x, x), x), f(x)) == 3 assert ode_order(diff(f(x), x, x), g(x)) == 0 assert ode_order(diff(f(x), x, x)*diff(g(x), x), f(x)) == 2 assert ode_order(diff(f(x), x, x)*diff(g(x), x), g(x)) == 1 assert ode_order(diff(x*diff(x*exp(f(x)), x, x), x), g(x)) == 0 # issue 5835: ode_order has to also work for unevaluated derivatives # (ie, without using doit()). assert ode_order(Derivative(x*f(x), x), f(x)) == 1 assert ode_order(x*sin(Derivative(x*f(x)**2, x, x)), f(x)) == 2 assert ode_order(Derivative(x*Derivative(x*exp(f(x)), x, x), x), g(x)) == 0 assert ode_order(Derivative(f(x), x, x), g(x)) == 0 assert ode_order(Derivative(x*exp(f(x)), x, x), f(x)) == 2 assert ode_order(Derivative(f(x), x, x)*Derivative(g(x), x), g(x)) == 1 assert ode_order(Derivative(x*Derivative(f(x), x, x), x), f(x)) == 3 assert ode_order( x*sin(Derivative(x*Derivative(f(x), x)**2, x, x)), f(x)) == 3 def test_homogeneous_order(): assert homogeneous_order(exp(y/x) + tan(y/x), x, y) == 0 assert homogeneous_order(x**2 + sin(x)*cos(y), x, y) is None assert homogeneous_order(x - y - x*sin(y/x), x, y) == 1 assert homogeneous_order((x*y + sqrt(x**4 + y**4) + x**2*(log(x) - log(y)))/ (pi*x**Rational(2, 3)*sqrt(y)**3), x, y) == Rational(-1, 6) assert homogeneous_order(y/x*cos(y/x) - x/y*sin(y/x) + cos(y/x), x, y) == 0 assert homogeneous_order(f(x), x, f(x)) == 1 assert homogeneous_order(f(x)**2, x, f(x)) == 2 assert homogeneous_order(x*y*z, x, y) == 2 assert homogeneous_order(x*y*z, x, y, z) == 3 assert homogeneous_order(x**2*f(x)/sqrt(x**2 + f(x)**2), f(x)) is None assert homogeneous_order(f(x, y)**2, x, f(x, y), y) == 2 assert homogeneous_order(f(x, y)**2, x, f(x), y) is None assert homogeneous_order(f(x, y)**2, x, f(x, y)) is None assert homogeneous_order(f(y, x)**2, x, y, f(x, y)) is None assert homogeneous_order(f(y), f(x), x) is None assert homogeneous_order(-f(x)/x + 1/sin(f(x)/ x), f(x), x) == 0 assert homogeneous_order(log(1/y) + log(x**2), x, y) is None assert homogeneous_order(log(1/y) + log(x), x, y) == 0 assert homogeneous_order(log(x/y), x, y) == 0 assert homogeneous_order(2*log(1/y) + 2*log(x), x, y) == 0 a = Symbol('a') assert homogeneous_order(a*log(1/y) + a*log(x), x, y) == 0 assert homogeneous_order(f(x).diff(x), x, y) is None assert homogeneous_order(-f(x).diff(x) + x, x, y) is None assert homogeneous_order(O(x), x, y) is None assert homogeneous_order(x + O(x**2), x, y) is None assert homogeneous_order(x**pi, x) == pi assert homogeneous_order(x**x, x) is None raises(ValueError, lambda: homogeneous_order(x*y)) @XFAIL def test_noncircularized_real_imaginary_parts(): # If this passes, lines numbered 3878-3882 (at the time of this commit) # of sympy/solvers/ode.py for nth_linear_constant_coeff_homogeneous # should be removed. y = sqrt(1+x) i, r = im(y), re(y) assert not (i.has(atan2) and r.has(atan2)) def test_collect_respecting_exponentials(): # If this test passes, lines 1306-1311 (at the time of this commit) # of sympy/solvers/ode.py should be removed. sol = 1 + exp(x/2) assert sol == collect( sol, exp(x/3)) def test_undetermined_coefficients_match(): assert _undetermined_coefficients_match(g(x), x) == {'test': False} assert _undetermined_coefficients_match(sin(2*x + sqrt(5)), x) == \ {'test': True, 'trialset': {cos(2*x + sqrt(5)), sin(2*x + sqrt(5))}} assert _undetermined_coefficients_match(sin(x)*cos(x), x) == \ {'test': False} s = {cos(x), x*cos(x), x**2*cos(x), x**2*sin(x), x*sin(x), sin(x)} assert _undetermined_coefficients_match(sin(x)*(x**2 + x + 1), x) == \ {'test': True, 'trialset': s} assert _undetermined_coefficients_match( sin(x)*x**2 + sin(x)*x + sin(x), x) == {'test': True, 'trialset': s} assert _undetermined_coefficients_match( exp(2*x)*sin(x)*(x**2 + x + 1), x ) == { 'test': True, 'trialset': {exp(2*x)*sin(x), x**2*exp(2*x)*sin(x), cos(x)*exp(2*x), x**2*cos(x)*exp(2*x), x*cos(x)*exp(2*x), x*exp(2*x)*sin(x)}} assert _undetermined_coefficients_match(1/sin(x), x) == {'test': False} assert _undetermined_coefficients_match(log(x), x) == {'test': False} assert _undetermined_coefficients_match(2**(x)*(x**2 + x + 1), x) == \ {'test': True, 'trialset': {2**x, x*2**x, x**2*2**x}} assert _undetermined_coefficients_match(x**y, x) == {'test': False} assert _undetermined_coefficients_match(exp(x)*exp(2*x + 1), x) == \ {'test': True, 'trialset': {exp(1 + 3*x)}} assert _undetermined_coefficients_match(sin(x)*(x**2 + x + 1), x) == \ {'test': True, 'trialset': {x*cos(x), x*sin(x), x**2*cos(x), x**2*sin(x), cos(x), sin(x)}} assert _undetermined_coefficients_match(sin(x)*(x + sin(x)), x) == \ {'test': False} assert _undetermined_coefficients_match(sin(x)*(x + sin(2*x)), x) == \ {'test': False} assert _undetermined_coefficients_match(sin(x)*tan(x), x) == \ {'test': False} assert _undetermined_coefficients_match( x**2*sin(x)*exp(x) + x*sin(x) + x, x ) == { 'test': True, 'trialset': {x**2*cos(x)*exp(x), x, cos(x), S.One, exp(x)*sin(x), sin(x), x*exp(x)*sin(x), x*cos(x), x*cos(x)*exp(x), x*sin(x), cos(x)*exp(x), x**2*exp(x)*sin(x)}} assert _undetermined_coefficients_match(4*x*sin(x - 2), x) == { 'trialset': {x*cos(x - 2), x*sin(x - 2), cos(x - 2), sin(x - 2)}, 'test': True, } assert _undetermined_coefficients_match(2**x*x, x) == \ {'test': True, 'trialset': {2**x, x*2**x}} assert _undetermined_coefficients_match(2**x*exp(2*x), x) == \ {'test': True, 'trialset': {2**x*exp(2*x)}} assert _undetermined_coefficients_match(exp(-x)/x, x) == \ {'test': False} # Below are from Ordinary Differential Equations, # Tenenbaum and Pollard, pg. 231 assert _undetermined_coefficients_match(S(4), x) == \ {'test': True, 'trialset': {S.One}} assert _undetermined_coefficients_match(12*exp(x), x) == \ {'test': True, 'trialset': {exp(x)}} assert _undetermined_coefficients_match(exp(I*x), x) == \ {'test': True, 'trialset': {exp(I*x)}} assert _undetermined_coefficients_match(sin(x), x) == \ {'test': True, 'trialset': {cos(x), sin(x)}} assert _undetermined_coefficients_match(cos(x), x) == \ {'test': True, 'trialset': {cos(x), sin(x)}} assert _undetermined_coefficients_match(8 + 6*exp(x) + 2*sin(x), x) == \ {'test': True, 'trialset': {S.One, cos(x), sin(x), exp(x)}} assert _undetermined_coefficients_match(x**2, x) == \ {'test': True, 'trialset': {S.One, x, x**2}} assert _undetermined_coefficients_match(9*x*exp(x) + exp(-x), x) == \ {'test': True, 'trialset': {x*exp(x), exp(x), exp(-x)}} assert _undetermined_coefficients_match(2*exp(2*x)*sin(x), x) == \ {'test': True, 'trialset': {exp(2*x)*sin(x), cos(x)*exp(2*x)}} assert _undetermined_coefficients_match(x - sin(x), x) == \ {'test': True, 'trialset': {S.One, x, cos(x), sin(x)}} assert _undetermined_coefficients_match(x**2 + 2*x, x) == \ {'test': True, 'trialset': {S.One, x, x**2}} assert _undetermined_coefficients_match(4*x*sin(x), x) == \ {'test': True, 'trialset': {x*cos(x), x*sin(x), cos(x), sin(x)}} assert _undetermined_coefficients_match(x*sin(2*x), x) == \ {'test': True, 'trialset': {x*cos(2*x), x*sin(2*x), cos(2*x), sin(2*x)}} assert _undetermined_coefficients_match(x**2*exp(-x), x) == \ {'test': True, 'trialset': {x*exp(-x), x**2*exp(-x), exp(-x)}} assert _undetermined_coefficients_match(2*exp(-x) - x**2*exp(-x), x) == \ {'test': True, 'trialset': {x*exp(-x), x**2*exp(-x), exp(-x)}} assert _undetermined_coefficients_match(exp(-2*x) + x**2, x) == \ {'test': True, 'trialset': {S.One, x, x**2, exp(-2*x)}} assert _undetermined_coefficients_match(x*exp(-x), x) == \ {'test': True, 'trialset': {x*exp(-x), exp(-x)}} assert _undetermined_coefficients_match(x + exp(2*x), x) == \ {'test': True, 'trialset': {S.One, x, exp(2*x)}} assert _undetermined_coefficients_match(sin(x) + exp(-x), x) == \ {'test': True, 'trialset': {cos(x), sin(x), exp(-x)}} assert _undetermined_coefficients_match(exp(x), x) == \ {'test': True, 'trialset': {exp(x)}} # converted from sin(x)**2 assert _undetermined_coefficients_match(S.Half - cos(2*x)/2, x) == \ {'test': True, 'trialset': {S.One, cos(2*x), sin(2*x)}} # converted from exp(2*x)*sin(x)**2 assert _undetermined_coefficients_match( exp(2*x)*(S.Half + cos(2*x)/2), x ) == { 'test': True, 'trialset': {exp(2*x)*sin(2*x), cos(2*x)*exp(2*x), exp(2*x)}} assert _undetermined_coefficients_match(2*x + sin(x) + cos(x), x) == \ {'test': True, 'trialset': {S.One, x, cos(x), sin(x)}} # converted from sin(2*x)*sin(x) assert _undetermined_coefficients_match(cos(x)/2 - cos(3*x)/2, x) == \ {'test': True, 'trialset': {cos(x), cos(3*x), sin(x), sin(3*x)}} assert _undetermined_coefficients_match(cos(x**2), x) == {'test': False} assert _undetermined_coefficients_match(2**(x**2), x) == {'test': False} def test_issue_4785(): from sympy.abc import A eq = x + A*(x + diff(f(x), x) + f(x)) + diff(f(x), x) + f(x) + 2 assert classify_ode(eq, f(x)) == ('1st_exact', '1st_linear', 'almost_linear', '1st_power_series', 'lie_group', 'nth_linear_constant_coeff_undetermined_coefficients', 'nth_linear_constant_coeff_variation_of_parameters', '1st_exact_Integral', '1st_linear_Integral', 'almost_linear_Integral', 'nth_linear_constant_coeff_variation_of_parameters_Integral') # issue 4864 eq = (x**2 + f(x)**2)*f(x).diff(x) - 2*x*f(x) assert classify_ode(eq, f(x)) == ('1st_exact', '1st_homogeneous_coeff_best', '1st_homogeneous_coeff_subs_indep_div_dep', '1st_homogeneous_coeff_subs_dep_div_indep', '1st_power_series', 'lie_group', '1st_exact_Integral', '1st_homogeneous_coeff_subs_indep_div_dep_Integral', '1st_homogeneous_coeff_subs_dep_div_indep_Integral') def test_issue_4825(): raises(ValueError, lambda: dsolve(f(x, y).diff(x) - y*f(x, y), f(x))) assert classify_ode(f(x, y).diff(x) - y*f(x, y), f(x), dict=True) == \ {'order': 0, 'default': None, 'ordered_hints': ()} # See also issue 3793, test Z13. raises(ValueError, lambda: dsolve(f(x).diff(x), f(y))) assert classify_ode(f(x).diff(x), f(y), dict=True) == \ {'order': 0, 'default': None, 'ordered_hints': ()} def test_constant_renumber_order_issue_5308(): from sympy.utilities.iterables import variations assert constant_renumber(C1*x + C2*y) == \ constant_renumber(C1*y + C2*x) == \ C1*x + C2*y e = C1*(C2 + x)*(C3 + y) for a, b, c in variations([C1, C2, C3], 3): assert constant_renumber(a*(b + x)*(c + y)) == e def test_constant_renumber(): e1, e2, x, y = symbols("e1:3 x y") exprs = [e2*x, e1*x + e2*y] assert constant_renumber(exprs[0]) == e2*x assert constant_renumber(exprs[0], variables=[x]) == C1*x assert constant_renumber(exprs[0], variables=[x], newconstants=[C2]) == C2*x assert constant_renumber(exprs, variables=[x, y]) == [C1*x, C1*y + C2*x] assert constant_renumber(exprs, variables=[x, y], newconstants=symbols("C3:5")) == [C3*x, C3*y + C4*x] def test_issue_5770(): k = Symbol("k", real=True) t = Symbol('t') w = Function('w') sol = dsolve(w(t).diff(t, 6) - k**6*w(t), w(t)) assert len([s for s in sol.free_symbols if s.name.startswith('C')]) == 6 assert constantsimp((C1*cos(x) + C2*cos(x))*exp(x), {C1, C2}) == \ C1*cos(x)*exp(x) assert constantsimp(C1*cos(x) + C2*cos(x) + C3*sin(x), {C1, C2, C3}) == \ C1*cos(x) + C3*sin(x) assert constantsimp(exp(C1 + x), {C1}) == C1*exp(x) assert constantsimp(x + C1 + y, {C1, y}) == C1 + x assert constantsimp(x + C1 + Integral(x, (x, 1, 2)), {C1}) == C1 + x def test_issue_5112_5430(): assert homogeneous_order(-log(x) + acosh(x), x) is None assert homogeneous_order(y - log(x), x, y) is None def test_issue_5095(): f = Function('f') raises(ValueError, lambda: dsolve(f(x).diff(x)**2, f(x), 'fdsjf')) def test_homogeneous_function(): f = Function('f') eq1 = tan(x + f(x)) eq2 = sin((3*x)/(4*f(x))) eq3 = cos(x*f(x)*Rational(3, 4)) eq4 = log((3*x + 4*f(x))/(5*f(x) + 7*x)) eq5 = exp((2*x**2)/(3*f(x)**2)) eq6 = log((3*x + 4*f(x))/(5*f(x) + 7*x) + exp((2*x**2)/(3*f(x)**2))) eq7 = sin((3*x)/(5*f(x) + x**2)) assert homogeneous_order(eq1, x, f(x)) == None assert homogeneous_order(eq2, x, f(x)) == 0 assert homogeneous_order(eq3, x, f(x)) == None assert homogeneous_order(eq4, x, f(x)) == 0 assert homogeneous_order(eq5, x, f(x)) == 0 assert homogeneous_order(eq6, x, f(x)) == 0 assert homogeneous_order(eq7, x, f(x)) == None def test_linear_coeff_match(): n, d = z*(2*x + 3*f(x) + 5), z*(7*x + 9*f(x) + 11) rat = n/d eq1 = sin(rat) + cos(rat.expand()) obj1 = LinearCoefficients(eq1) eq2 = rat obj2 = LinearCoefficients(eq2) eq3 = log(sin(rat)) obj3 = LinearCoefficients(eq3) ans = (4, Rational(-13, 3)) assert obj1._linear_coeff_match(eq1, f(x)) == ans assert obj2._linear_coeff_match(eq2, f(x)) == ans assert obj3._linear_coeff_match(eq3, f(x)) == ans # no c eq4 = (3*x)/f(x) obj4 = LinearCoefficients(eq4) # not x and f(x) eq5 = (3*x + 2)/x obj5 = LinearCoefficients(eq5) # denom will be zero eq6 = (3*x + 2*f(x) + 1)/(3*x + 2*f(x) + 5) obj6 = LinearCoefficients(eq6) # not rational coefficient eq7 = (3*x + 2*f(x) + sqrt(2))/(3*x + 2*f(x) + 5) obj7 = LinearCoefficients(eq7) assert obj4._linear_coeff_match(eq4, f(x)) is None assert obj5._linear_coeff_match(eq5, f(x)) is None assert obj6._linear_coeff_match(eq6, f(x)) is None assert obj7._linear_coeff_match(eq7, f(x)) is None def test_constantsimp_take_problem(): c = exp(C1) + 2 assert len(Poly(constantsimp(exp(C1) + c + c*x, [C1])).gens) == 2 def test_series(): C1 = Symbol("C1") eq = f(x).diff(x) - f(x) sol = Eq(f(x), C1 + C1*x + C1*x**2/2 + C1*x**3/6 + C1*x**4/24 + C1*x**5/120 + O(x**6)) assert dsolve(eq, hint='1st_power_series') == sol assert checkodesol(eq, sol, order=1)[0] eq = f(x).diff(x) - x*f(x) sol = Eq(f(x), C1*x**4/8 + C1*x**2/2 + C1 + O(x**6)) assert dsolve(eq, hint='1st_power_series') == sol assert checkodesol(eq, sol, order=1)[0] eq = f(x).diff(x) - sin(x*f(x)) sol = Eq(f(x), (x - 2)**2*(1+ sin(4))*cos(4) + (x - 2)*sin(4) + 2 + O(x**3)) assert dsolve(eq, hint='1st_power_series', ics={f(2): 2}, n=3) == sol # FIXME: The solution here should be O((x-2)**3) so is incorrect #assert checkodesol(eq, sol, order=1)[0] @slow def test_2nd_power_series_ordinary(): C1, C2 = symbols("C1 C2") eq = f(x).diff(x, 2) - x*f(x) assert classify_ode(eq) == ('2nd_linear_airy', '2nd_power_series_ordinary') sol = Eq(f(x), C2*(x**3/6 + 1) + C1*x*(x**3/12 + 1) + O(x**6)) assert dsolve(eq, hint='2nd_power_series_ordinary') == sol assert checkodesol(eq, sol) == (True, 0) sol = Eq(f(x), C2*((x + 2)**4/6 + (x + 2)**3/6 - (x + 2)**2 + 1) + C1*(x + (x + 2)**4/12 - (x + 2)**3/3 + S(2)) + O(x**6)) assert dsolve(eq, hint='2nd_power_series_ordinary', x0=-2) == sol # FIXME: Solution should be O((x+2)**6) # assert checkodesol(eq, sol) == (True, 0) sol = Eq(f(x), C2*x + C1 + O(x**2)) assert dsolve(eq, hint='2nd_power_series_ordinary', n=2) == sol assert checkodesol(eq, sol) == (True, 0) eq = (1 + x**2)*(f(x).diff(x, 2)) + 2*x*(f(x).diff(x)) -2*f(x) assert classify_ode(eq) == ('2nd_power_series_ordinary',) sol = Eq(f(x), C2*(-x**4/3 + x**2 + 1) + C1*x + O(x**6)) assert dsolve(eq) == sol assert checkodesol(eq, sol) == (True, 0) eq = f(x).diff(x, 2) + x*(f(x).diff(x)) + f(x) assert classify_ode(eq) == ('2nd_power_series_ordinary',) sol = Eq(f(x), C2*(x**4/8 - x**2/2 + 1) + C1*x*(-x**2/3 + 1) + O(x**6)) assert dsolve(eq) == sol # FIXME: checkodesol fails for this solution... # assert checkodesol(eq, sol) == (True, 0) eq = f(x).diff(x, 2) + f(x).diff(x) - x*f(x) assert classify_ode(eq) == ('2nd_power_series_ordinary',) sol = Eq(f(x), C2*(-x**4/24 + x**3/6 + 1) + C1*x*(x**3/24 + x**2/6 - x/2 + 1) + O(x**6)) assert dsolve(eq) == sol # FIXME: checkodesol fails for this solution... # assert checkodesol(eq, sol) == (True, 0) eq = f(x).diff(x, 2) + x*f(x) assert classify_ode(eq) == ('2nd_linear_airy', '2nd_power_series_ordinary') sol = Eq(f(x), C2*(x**6/180 - x**3/6 + 1) + C1*x*(-x**3/12 + 1) + O(x**7)) assert dsolve(eq, hint='2nd_power_series_ordinary', n=7) == sol assert checkodesol(eq, sol) == (True, 0) def test_2nd_power_series_regular(): C1, C2, a = symbols("C1 C2 a") eq = x**2*(f(x).diff(x, 2)) - 3*x*(f(x).diff(x)) + (4*x + 4)*f(x) sol = Eq(f(x), C1*x**2*(-16*x**3/9 + 4*x**2 - 4*x + 1) + O(x**6)) assert dsolve(eq, hint='2nd_power_series_regular') == sol assert checkodesol(eq, sol) == (True, 0) eq = 4*x**2*(f(x).diff(x, 2)) -8*x**2*(f(x).diff(x)) + (4*x**2 + 1)*f(x) sol = Eq(f(x), C1*sqrt(x)*(x**4/24 + x**3/6 + x**2/2 + x + 1) + O(x**6)) assert dsolve(eq, hint='2nd_power_series_regular') == sol assert checkodesol(eq, sol) == (True, 0) eq = x**2*(f(x).diff(x, 2)) - x**2*(f(x).diff(x)) + ( x**2 - 2)*f(x) sol = Eq(f(x), C1*(-x**6/720 - 3*x**5/80 - x**4/8 + x**2/2 + x/2 + 1)/x + C2*x**2*(-x**3/60 + x**2/20 + x/2 + 1) + O(x**6)) assert dsolve(eq) == sol assert checkodesol(eq, sol) == (True, 0) eq = x**2*(f(x).diff(x, 2)) + x*(f(x).diff(x)) + (x**2 - Rational(1, 4))*f(x) sol = Eq(f(x), C1*(x**4/24 - x**2/2 + 1)/sqrt(x) + C2*sqrt(x)*(x**4/120 - x**2/6 + 1) + O(x**6)) assert dsolve(eq, hint='2nd_power_series_regular') == sol assert checkodesol(eq, sol) == (True, 0) eq = x*f(x).diff(x, 2) + f(x).diff(x) - a*x*f(x) sol = Eq(f(x), C1*(a**2*x**4/64 + a*x**2/4 + 1) + O(x**6)) assert dsolve(eq, f(x), hint="2nd_power_series_regular") == sol assert checkodesol(eq, sol) == (True, 0) eq = f(x).diff(x, 2) + ((1 - x)/x)*f(x).diff(x) + (a/x)*f(x) sol = Eq(f(x), C1*(-a*x**5*(a - 4)*(a - 3)*(a - 2)*(a - 1)/14400 + \ a*x**4*(a - 3)*(a - 2)*(a - 1)/576 - a*x**3*(a - 2)*(a - 1)/36 + \ a*x**2*(a - 1)/4 - a*x + 1) + O(x**6)) assert dsolve(eq, f(x), hint="2nd_power_series_regular") == sol assert checkodesol(eq, sol) == (True, 0) def test_issue_15056(): t = Symbol('t') C3 = Symbol('C3') assert get_numbered_constants(Symbol('C1') * Function('C2')(t)) == C3 def test_issue_15913(): eq = -C1/x - 2*x*f(x) - f(x) + Derivative(f(x), x) sol = C2*exp(x**2 + x) + exp(x**2 + x)*Integral(C1*exp(-x**2 - x)/x, x) assert checkodesol(eq, sol) == (True, 0) sol = C1 + C2*exp(-x*y) eq = Derivative(y*f(x), x) + f(x).diff(x, 2) assert checkodesol(eq, sol, f(x)) == (True, 0) def test_issue_16146(): raises(ValueError, lambda: dsolve([f(x).diff(x), g(x).diff(x)], [f(x), g(x), h(x)])) raises(ValueError, lambda: dsolve([f(x).diff(x), g(x).diff(x)], [f(x)])) def test_dsolve_remove_redundant_solutions(): eq = (f(x)-2)*f(x).diff(x) sol = Eq(f(x), C1) assert dsolve(eq) == sol eq = (f(x)-sin(x))*(f(x).diff(x, 2)) sol = {Eq(f(x), C1 + C2*x), Eq(f(x), sin(x))} assert set(dsolve(eq)) == sol eq = (f(x)**2-2*f(x)+1)*f(x).diff(x, 3) sol = Eq(f(x), C1 + C2*x + C3*x**2) assert dsolve(eq) == sol def test_issue_13060(): A, B = symbols("A B", cls=Function) t = Symbol("t") eq = [Eq(Derivative(A(t), t), A(t)*B(t)), Eq(Derivative(B(t), t), A(t)*B(t))] sol = dsolve(eq) assert checkodesol(eq, sol) == (True, [0, 0])
e2bd9b0ac3054f75b3f03abd385928e29921b36741c8357222b55a3781b7968d
from sympy.core.backend import (S, sympify, expand, sqrt, Add, zeros, acos, ImmutableMatrix as Matrix) from sympy import trigsimp from sympy.printing.defaults import Printable from sympy.utilities.misc import filldedent from sympy.core.evalf import EvalfMixin, prec_to_dps __all__ = ['Vector'] class Vector(Printable, EvalfMixin): """The class used to define vectors. It along with ReferenceFrame are the building blocks of describing a classical mechanics system in PyDy and sympy.physics.vector. Attributes ========== simp : Boolean Let certain methods use trigsimp on their outputs """ simp = False is_number = False def __init__(self, inlist): """This is the constructor for the Vector class. You shouldn't be calling this, it should only be used by other functions. You should be treating Vectors like you would with if you were doing the math by hand, and getting the first 3 from the standard basis vectors from a ReferenceFrame. The only exception is to create a zero vector: zv = Vector(0) """ self.args = [] if inlist == 0: inlist = [] if isinstance(inlist, dict): d = inlist else: d = {} for inp in inlist: if inp[1] in d: d[inp[1]] += inp[0] else: d[inp[1]] = inp[0] for k, v in d.items(): if v != Matrix([0, 0, 0]): self.args.append((v, k)) @property def func(self): """Returns the class Vector. """ return Vector def __hash__(self): return hash(tuple(self.args)) def __add__(self, other): """The add operator for Vector. """ if other == 0: return self other = _check_vector(other) return Vector(self.args + other.args) def __and__(self, other): """Dot product of two vectors. Returns a scalar, the dot product of the two Vectors Parameters ========== other : Vector The Vector which we are dotting with Examples ======== >>> from sympy.physics.vector import ReferenceFrame, dot >>> from sympy import symbols >>> q1 = symbols('q1') >>> N = ReferenceFrame('N') >>> dot(N.x, N.x) 1 >>> dot(N.x, N.y) 0 >>> A = N.orientnew('A', 'Axis', [q1, N.x]) >>> dot(N.y, A.y) cos(q1) """ from sympy.physics.vector.dyadic import Dyadic if isinstance(other, Dyadic): return NotImplemented other = _check_vector(other) out = S.Zero for i, v1 in enumerate(self.args): for j, v2 in enumerate(other.args): out += ((v2[0].T) * (v2[1].dcm(v1[1])) * (v1[0]))[0] if Vector.simp: return trigsimp(sympify(out), recursive=True) else: return sympify(out) def __truediv__(self, other): """This uses mul and inputs self and 1 divided by other. """ return self.__mul__(sympify(1) / other) def __eq__(self, other): """Tests for equality. It is very import to note that this is only as good as the SymPy equality test; False does not always mean they are not equivalent Vectors. If other is 0, and self is empty, returns True. If other is 0 and self is not empty, returns False. If none of the above, only accepts other as a Vector. """ if other == 0: other = Vector(0) try: other = _check_vector(other) except TypeError: return False if (self.args == []) and (other.args == []): return True elif (self.args == []) or (other.args == []): return False frame = self.args[0][1] for v in frame: if expand((self - other) & v) != 0: return False return True def __mul__(self, other): """Multiplies the Vector by a sympifyable expression. Parameters ========== other : Sympifyable The scalar to multiply this Vector with Examples ======== >>> from sympy.physics.vector import ReferenceFrame >>> from sympy import Symbol >>> N = ReferenceFrame('N') >>> b = Symbol('b') >>> V = 10 * b * N.x >>> print(V) 10*b*N.x """ newlist = [v for v in self.args] for i, v in enumerate(newlist): newlist[i] = (sympify(other) * newlist[i][0], newlist[i][1]) return Vector(newlist) def __ne__(self, other): return not self == other def __neg__(self): return self * -1 def __or__(self, other): """Outer product between two Vectors. A rank increasing operation, which returns a Dyadic from two Vectors Parameters ========== other : Vector The Vector to take the outer product with Examples ======== >>> from sympy.physics.vector import ReferenceFrame, outer >>> N = ReferenceFrame('N') >>> outer(N.x, N.x) (N.x|N.x) """ from sympy.physics.vector.dyadic import Dyadic other = _check_vector(other) ol = Dyadic(0) for i, v in enumerate(self.args): for i2, v2 in enumerate(other.args): # it looks this way because if we are in the same frame and # use the enumerate function on the same frame in a nested # fashion, then bad things happen ol += Dyadic([(v[0][0] * v2[0][0], v[1].x, v2[1].x)]) ol += Dyadic([(v[0][0] * v2[0][1], v[1].x, v2[1].y)]) ol += Dyadic([(v[0][0] * v2[0][2], v[1].x, v2[1].z)]) ol += Dyadic([(v[0][1] * v2[0][0], v[1].y, v2[1].x)]) ol += Dyadic([(v[0][1] * v2[0][1], v[1].y, v2[1].y)]) ol += Dyadic([(v[0][1] * v2[0][2], v[1].y, v2[1].z)]) ol += Dyadic([(v[0][2] * v2[0][0], v[1].z, v2[1].x)]) ol += Dyadic([(v[0][2] * v2[0][1], v[1].z, v2[1].y)]) ol += Dyadic([(v[0][2] * v2[0][2], v[1].z, v2[1].z)]) return ol def _latex(self, printer): """Latex Printing method. """ ar = self.args # just to shorten things if len(ar) == 0: return str(0) ol = [] # output list, to be concatenated to a string for i, v in enumerate(ar): for j in 0, 1, 2: # if the coef of the basis vector is 1, we skip the 1 if ar[i][0][j] == 1: ol.append(' + ' + ar[i][1].latex_vecs[j]) # if the coef of the basis vector is -1, we skip the 1 elif ar[i][0][j] == -1: ol.append(' - ' + ar[i][1].latex_vecs[j]) elif ar[i][0][j] != 0: # If the coefficient of the basis vector is not 1 or -1; # also, we might wrap it in parentheses, for readability. arg_str = printer._print(ar[i][0][j]) if isinstance(ar[i][0][j], Add): arg_str = "(%s)" % arg_str if arg_str[0] == '-': arg_str = arg_str[1:] str_start = ' - ' else: str_start = ' + ' ol.append(str_start + arg_str + ar[i][1].latex_vecs[j]) outstr = ''.join(ol) if outstr.startswith(' + '): outstr = outstr[3:] elif outstr.startswith(' '): outstr = outstr[1:] return outstr def _pretty(self, printer): """Pretty Printing method. """ from sympy.printing.pretty.stringpict import prettyForm e = self class Fake: def render(self, *args, **kwargs): ar = e.args # just to shorten things if len(ar) == 0: return str(0) pforms = [] # output list, to be concatenated to a string for i, v in enumerate(ar): for j in 0, 1, 2: # if the coef of the basis vector is 1, we skip the 1 if ar[i][0][j] == 1: pform = printer._print(ar[i][1].pretty_vecs[j]) # if the coef of the basis vector is -1, we skip the 1 elif ar[i][0][j] == -1: pform = printer._print(ar[i][1].pretty_vecs[j]) pform = prettyForm(*pform.left(" - ")) bin = prettyForm.NEG pform = prettyForm(binding=bin, *pform) elif ar[i][0][j] != 0: # If the basis vector coeff is not 1 or -1, # we might wrap it in parentheses, for readability. pform = printer._print(ar[i][0][j]) if isinstance(ar[i][0][j], Add): tmp = pform.parens() pform = prettyForm(tmp[0], tmp[1]) pform = prettyForm(*pform.right(" ", ar[i][1].pretty_vecs[j])) else: continue pforms.append(pform) pform = prettyForm.__add__(*pforms) kwargs["wrap_line"] = kwargs.get("wrap_line") kwargs["num_columns"] = kwargs.get("num_columns") out_str = pform.render(*args, **kwargs) mlines = [line.rstrip() for line in out_str.split("\n")] return "\n".join(mlines) return Fake() def __ror__(self, other): """Outer product between two Vectors. A rank increasing operation, which returns a Dyadic from two Vectors Parameters ========== other : Vector The Vector to take the outer product with Examples ======== >>> from sympy.physics.vector import ReferenceFrame, outer >>> N = ReferenceFrame('N') >>> outer(N.x, N.x) (N.x|N.x) """ from sympy.physics.vector.dyadic import Dyadic other = _check_vector(other) ol = Dyadic(0) for i, v in enumerate(other.args): for i2, v2 in enumerate(self.args): # it looks this way because if we are in the same frame and # use the enumerate function on the same frame in a nested # fashion, then bad things happen ol += Dyadic([(v[0][0] * v2[0][0], v[1].x, v2[1].x)]) ol += Dyadic([(v[0][0] * v2[0][1], v[1].x, v2[1].y)]) ol += Dyadic([(v[0][0] * v2[0][2], v[1].x, v2[1].z)]) ol += Dyadic([(v[0][1] * v2[0][0], v[1].y, v2[1].x)]) ol += Dyadic([(v[0][1] * v2[0][1], v[1].y, v2[1].y)]) ol += Dyadic([(v[0][1] * v2[0][2], v[1].y, v2[1].z)]) ol += Dyadic([(v[0][2] * v2[0][0], v[1].z, v2[1].x)]) ol += Dyadic([(v[0][2] * v2[0][1], v[1].z, v2[1].y)]) ol += Dyadic([(v[0][2] * v2[0][2], v[1].z, v2[1].z)]) return ol def __rsub__(self, other): return (-1 * self) + other def _sympystr(self, printer, order=True): """Printing method. """ if not order or len(self.args) == 1: ar = list(self.args) elif len(self.args) == 0: return printer._print(0) else: d = {v[1]: v[0] for v in self.args} keys = sorted(d.keys(), key=lambda x: x.index) ar = [] for key in keys: ar.append((d[key], key)) ol = [] # output list, to be concatenated to a string for i, v in enumerate(ar): for j in 0, 1, 2: # if the coef of the basis vector is 1, we skip the 1 if ar[i][0][j] == 1: ol.append(' + ' + ar[i][1].str_vecs[j]) # if the coef of the basis vector is -1, we skip the 1 elif ar[i][0][j] == -1: ol.append(' - ' + ar[i][1].str_vecs[j]) elif ar[i][0][j] != 0: # If the coefficient of the basis vector is not 1 or -1; # also, we might wrap it in parentheses, for readability. arg_str = printer._print(ar[i][0][j]) if isinstance(ar[i][0][j], Add): arg_str = "(%s)" % arg_str if arg_str[0] == '-': arg_str = arg_str[1:] str_start = ' - ' else: str_start = ' + ' ol.append(str_start + arg_str + '*' + ar[i][1].str_vecs[j]) outstr = ''.join(ol) if outstr.startswith(' + '): outstr = outstr[3:] elif outstr.startswith(' '): outstr = outstr[1:] return outstr def __sub__(self, other): """The subtraction operator. """ return self.__add__(other * -1) def __xor__(self, other): """The cross product operator for two Vectors. Returns a Vector, expressed in the same ReferenceFrames as self. Parameters ========== other : Vector The Vector which we are crossing with Examples ======== >>> from sympy.physics.vector import ReferenceFrame >>> from sympy import symbols >>> q1 = symbols('q1') >>> N = ReferenceFrame('N') >>> N.x ^ N.y N.z >>> A = N.orientnew('A', 'Axis', [q1, N.x]) >>> A.x ^ N.y N.z >>> N.y ^ A.x - sin(q1)*A.y - cos(q1)*A.z """ from sympy.physics.vector.dyadic import Dyadic if isinstance(other, Dyadic): return NotImplemented other = _check_vector(other) if other.args == []: return Vector(0) def _det(mat): """This is needed as a little method for to find the determinant of a list in python; needs to work for a 3x3 list. SymPy's Matrix won't take in Vector, so need a custom function. You shouldn't be calling this. """ return (mat[0][0] * (mat[1][1] * mat[2][2] - mat[1][2] * mat[2][1]) + mat[0][1] * (mat[1][2] * mat[2][0] - mat[1][0] * mat[2][2]) + mat[0][2] * (mat[1][0] * mat[2][1] - mat[1][1] * mat[2][0])) outlist = [] ar = other.args # For brevity for i, v in enumerate(ar): tempx = v[1].x tempy = v[1].y tempz = v[1].z tempm = ([[tempx, tempy, tempz], [self & tempx, self & tempy, self & tempz], [Vector([ar[i]]) & tempx, Vector([ar[i]]) & tempy, Vector([ar[i]]) & tempz]]) outlist += _det(tempm).args return Vector(outlist) __radd__ = __add__ __rand__ = __and__ __rmul__ = __mul__ def separate(self): """ The constituents of this vector in different reference frames, as per its definition. Returns a dict mapping each ReferenceFrame to the corresponding constituent Vector. Examples ======== >>> from sympy.physics.vector import ReferenceFrame >>> R1 = ReferenceFrame('R1') >>> R2 = ReferenceFrame('R2') >>> v = R1.x + R2.x >>> v.separate() == {R1: R1.x, R2: R2.x} True """ components = {} for x in self.args: components[x[1]] = Vector([x]) return components def dot(self, other): return self & other dot.__doc__ = __and__.__doc__ def cross(self, other): return self ^ other cross.__doc__ = __xor__.__doc__ def outer(self, other): return self | other outer.__doc__ = __or__.__doc__ def diff(self, var, frame, var_in_dcm=True): """Returns the partial derivative of the vector with respect to a variable in the provided reference frame. Parameters ========== var : Symbol What the partial derivative is taken with respect to. frame : ReferenceFrame The reference frame that the partial derivative is taken in. var_in_dcm : boolean If true, the differentiation algorithm assumes that the variable may be present in any of the direction cosine matrices that relate the frame to the frames of any component of the vector. But if it is known that the variable is not present in the direction cosine matrices, false can be set to skip full reexpression in the desired frame. Examples ======== >>> from sympy import Symbol >>> from sympy.physics.vector import dynamicsymbols, ReferenceFrame >>> from sympy.physics.vector import Vector >>> from sympy.physics.vector import init_vprinting >>> init_vprinting(pretty_print=False) >>> Vector.simp = True >>> t = Symbol('t') >>> q1 = dynamicsymbols('q1') >>> N = ReferenceFrame('N') >>> A = N.orientnew('A', 'Axis', [q1, N.y]) >>> A.x.diff(t, N) - q1'*A.z >>> B = ReferenceFrame('B') >>> u1, u2 = dynamicsymbols('u1, u2') >>> v = u1 * A.x + u2 * B.y >>> v.diff(u2, N, var_in_dcm=False) B.y """ from sympy.physics.vector.frame import _check_frame var = sympify(var) _check_frame(frame) inlist = [] for vector_component in self.args: measure_number = vector_component[0] component_frame = vector_component[1] if component_frame == frame: inlist += [(measure_number.diff(var), frame)] else: # If the direction cosine matrix relating the component frame # with the derivative frame does not contain the variable. if not var_in_dcm or (frame.dcm(component_frame).diff(var) == zeros(3, 3)): inlist += [(measure_number.diff(var), component_frame)] else: # else express in the frame reexp_vec_comp = Vector([vector_component]).express(frame) deriv = reexp_vec_comp.args[0][0].diff(var) inlist += Vector([(deriv, frame)]).express(component_frame).args return Vector(inlist) def express(self, otherframe, variables=False): """ Returns a Vector equivalent to this one, expressed in otherframe. Uses the global express method. Parameters ========== otherframe : ReferenceFrame The frame for this Vector to be described in variables : boolean If True, the coordinate symbols(if present) in this Vector are re-expressed in terms otherframe Examples ======== >>> from sympy.physics.vector import ReferenceFrame, dynamicsymbols >>> from sympy.physics.vector import init_vprinting >>> init_vprinting(pretty_print=False) >>> q1 = dynamicsymbols('q1') >>> N = ReferenceFrame('N') >>> A = N.orientnew('A', 'Axis', [q1, N.y]) >>> A.x.express(N) cos(q1)*N.x - sin(q1)*N.z """ from sympy.physics.vector import express return express(self, otherframe, variables=variables) def to_matrix(self, reference_frame): """Returns the matrix form of the vector with respect to the given frame. Parameters ---------- reference_frame : ReferenceFrame The reference frame that the rows of the matrix correspond to. Returns ------- matrix : ImmutableMatrix, shape(3,1) The matrix that gives the 1D vector. Examples ======== >>> from sympy import symbols >>> from sympy.physics.vector import ReferenceFrame >>> a, b, c = symbols('a, b, c') >>> N = ReferenceFrame('N') >>> vector = a * N.x + b * N.y + c * N.z >>> vector.to_matrix(N) Matrix([ [a], [b], [c]]) >>> beta = symbols('beta') >>> A = N.orientnew('A', 'Axis', (beta, N.x)) >>> vector.to_matrix(A) Matrix([ [ a], [ b*cos(beta) + c*sin(beta)], [-b*sin(beta) + c*cos(beta)]]) """ return Matrix([self.dot(unit_vec) for unit_vec in reference_frame]).reshape(3, 1) def doit(self, **hints): """Calls .doit() on each term in the Vector""" d = {} for v in self.args: d[v[1]] = v[0].applyfunc(lambda x: x.doit(**hints)) return Vector(d) def dt(self, otherframe): """ Returns a Vector which is the time derivative of the self Vector, taken in frame otherframe. Calls the global time_derivative method Parameters ========== otherframe : ReferenceFrame The frame to calculate the time derivative in """ from sympy.physics.vector import time_derivative return time_derivative(self, otherframe) def simplify(self): """Returns a simplified Vector.""" d = {} for v in self.args: d[v[1]] = v[0].simplify() return Vector(d) def subs(self, *args, **kwargs): """Substitution on the Vector. Examples ======== >>> from sympy.physics.vector import ReferenceFrame >>> from sympy import Symbol >>> N = ReferenceFrame('N') >>> s = Symbol('s') >>> a = N.x * s >>> a.subs({s: 2}) 2*N.x """ d = {} for v in self.args: d[v[1]] = v[0].subs(*args, **kwargs) return Vector(d) def magnitude(self): """Returns the magnitude (Euclidean norm) of self.""" return sqrt(self & self) def normalize(self): """Returns a Vector of magnitude 1, codirectional with self.""" return Vector(self.args + []) / self.magnitude() def applyfunc(self, f): """Apply a function to each component of a vector.""" if not callable(f): raise TypeError("`f` must be callable.") d = {} for v in self.args: d[v[1]] = v[0].applyfunc(f) return Vector(d) def angle_between(self, vec): """ Returns the smallest angle between Vector 'vec' and self. Parameter ========= vec : Vector The Vector between which angle is needed. Examples ======== >>> from sympy.physics.vector import ReferenceFrame >>> A = ReferenceFrame("A") >>> v1 = A.x >>> v2 = A.y >>> v1.angle_between(v2) pi/2 >>> v3 = A.x + A.y + A.z >>> v1.angle_between(v3) acos(sqrt(3)/3) """ vec1 = self.normalize() vec2 = vec.normalize() angle = acos(vec1.dot(vec2)) return angle def free_symbols(self, reference_frame): """ Returns the free symbols in the measure numbers of the vector expressed in the given reference frame. Parameter ========= reference_frame : ReferenceFrame The frame with respect to which the free symbols of the given vector is to be determined. """ return self.to_matrix(reference_frame).free_symbols def _eval_evalf(self, prec): if not self.args: return self new_args = [] for mat, frame in self.args: new_args.append([mat.evalf(n=prec_to_dps(prec)), frame]) return Vector(new_args) def xreplace(self, rule): """ Replace occurrences of objects within the measure numbers of the vector. Parameters ========== rule : dict-like Expresses a replacement rule. Returns ======= Vector Result of the replacement. Examples ======== >>> from sympy import symbols, pi >>> from sympy.physics.vector import ReferenceFrame >>> A = ReferenceFrame('A') >>> x, y, z = symbols('x y z') >>> ((1 + x*y) * A.x).xreplace({x: pi}) (pi*y + 1)*A.x >>> ((1 + x*y) * A.x).xreplace({x: pi, y: 2}) (1 + 2*pi)*A.x Replacements occur only if an entire node in the expression tree is matched: >>> ((x*y + z) * A.x).xreplace({x*y: pi}) (z + pi)*A.x >>> ((x*y*z) * A.x).xreplace({x*y: pi}) x*y*z*A.x """ new_args = [] for mat, frame in self.args: mat = mat.xreplace(rule) new_args.append([mat, frame]) return Vector(new_args) class VectorTypeError(TypeError): def __init__(self, other, want): msg = filldedent("Expected an instance of %s, but received object " "'%s' of %s." % (type(want), other, type(other))) super().__init__(msg) def _check_vector(other): if not isinstance(other, Vector): raise TypeError('A Vector must be supplied') return other
0f9f43805bda26eedc36f61a74d850413c5968ca64d3f6c244307a65cf0b12e8
from sympy import symbols, pi, sin, cos, Float, ImmutableMatrix as Matrix from sympy.physics.vector import ReferenceFrame, Vector, dynamicsymbols, dot from sympy.abc import x, y, z from sympy.testing.pytest import raises Vector.simp = True A = ReferenceFrame('A') def test_Vector(): assert A.x != A.y assert A.y != A.z assert A.z != A.x assert A.x + 0 == A.x v1 = x*A.x + y*A.y + z*A.z v2 = x**2*A.x + y**2*A.y + z**2*A.z v3 = v1 + v2 v4 = v1 - v2 assert isinstance(v1, Vector) assert dot(v1, A.x) == x assert dot(v1, A.y) == y assert dot(v1, A.z) == z assert isinstance(v2, Vector) assert dot(v2, A.x) == x**2 assert dot(v2, A.y) == y**2 assert dot(v2, A.z) == z**2 assert isinstance(v3, Vector) # We probably shouldn't be using simplify in dot... assert dot(v3, A.x) == x**2 + x assert dot(v3, A.y) == y**2 + y assert dot(v3, A.z) == z**2 + z assert isinstance(v4, Vector) # We probably shouldn't be using simplify in dot... assert dot(v4, A.x) == x - x**2 assert dot(v4, A.y) == y - y**2 assert dot(v4, A.z) == z - z**2 assert v1.to_matrix(A) == Matrix([[x], [y], [z]]) q = symbols('q') B = A.orientnew('B', 'Axis', (q, A.x)) assert v1.to_matrix(B) == Matrix([[x], [ y * cos(q) + z * sin(q)], [-y * sin(q) + z * cos(q)]]) #Test the separate method B = ReferenceFrame('B') v5 = x*A.x + y*A.y + z*B.z assert Vector(0).separate() == {} assert v1.separate() == {A: v1} assert v5.separate() == {A: x*A.x + y*A.y, B: z*B.z} #Test the free_symbols property v6 = x*A.x + y*A.y + z*A.z assert v6.free_symbols(A) == {x,y,z} raises(TypeError, lambda: v3.applyfunc(v1)) def test_Vector_diffs(): q1, q2, q3, q4 = dynamicsymbols('q1 q2 q3 q4') q1d, q2d, q3d, q4d = dynamicsymbols('q1 q2 q3 q4', 1) q1dd, q2dd, q3dd, q4dd = dynamicsymbols('q1 q2 q3 q4', 2) N = ReferenceFrame('N') A = N.orientnew('A', 'Axis', [q3, N.z]) B = A.orientnew('B', 'Axis', [q2, A.x]) v1 = q2 * A.x + q3 * N.y v2 = q3 * B.x + v1 v3 = v1.dt(B) v4 = v2.dt(B) v5 = q1*A.x + q2*A.y + q3*A.z assert v1.dt(N) == q2d * A.x + q2 * q3d * A.y + q3d * N.y assert v1.dt(A) == q2d * A.x + q3 * q3d * N.x + q3d * N.y assert v1.dt(B) == (q2d * A.x + q3 * q3d * N.x + q3d *\ N.y - q3 * cos(q3) * q2d * N.z) assert v2.dt(N) == (q2d * A.x + (q2 + q3) * q3d * A.y + q3d * B.x + q3d * N.y) assert v2.dt(A) == q2d * A.x + q3d * B.x + q3 * q3d * N.x + q3d * N.y assert v2.dt(B) == (q2d * A.x + q3d * B.x + q3 * q3d * N.x + q3d * N.y - q3 * cos(q3) * q2d * N.z) assert v3.dt(N) == (q2dd * A.x + q2d * q3d * A.y + (q3d**2 + q3 * q3dd) * N.x + q3dd * N.y + (q3 * sin(q3) * q2d * q3d - cos(q3) * q2d * q3d - q3 * cos(q3) * q2dd) * N.z) assert v3.dt(A) == (q2dd * A.x + (2 * q3d**2 + q3 * q3dd) * N.x + (q3dd - q3 * q3d**2) * N.y + (q3 * sin(q3) * q2d * q3d - cos(q3) * q2d * q3d - q3 * cos(q3) * q2dd) * N.z) assert v3.dt(B) == (q2dd * A.x - q3 * cos(q3) * q2d**2 * A.y + (2 * q3d**2 + q3 * q3dd) * N.x + (q3dd - q3 * q3d**2) * N.y + (2 * q3 * sin(q3) * q2d * q3d - 2 * cos(q3) * q2d * q3d - q3 * cos(q3) * q2dd) * N.z) assert v4.dt(N) == (q2dd * A.x + q3d * (q2d + q3d) * A.y + q3dd * B.x + (q3d**2 + q3 * q3dd) * N.x + q3dd * N.y + (q3 * sin(q3) * q2d * q3d - cos(q3) * q2d * q3d - q3 * cos(q3) * q2dd) * N.z) assert v4.dt(A) == (q2dd * A.x + q3dd * B.x + (2 * q3d**2 + q3 * q3dd) * N.x + (q3dd - q3 * q3d**2) * N.y + (q3 * sin(q3) * q2d * q3d - cos(q3) * q2d * q3d - q3 * cos(q3) * q2dd) * N.z) assert v4.dt(B) == (q2dd * A.x - q3 * cos(q3) * q2d**2 * A.y + q3dd * B.x + (2 * q3d**2 + q3 * q3dd) * N.x + (q3dd - q3 * q3d**2) * N.y + (2 * q3 * sin(q3) * q2d * q3d - 2 * cos(q3) * q2d * q3d - q3 * cos(q3) * q2dd) * N.z) assert v5.dt(B) == q1d*A.x + (q3*q2d + q2d)*A.y + (-q2*q2d + q3d)*A.z assert v5.dt(A) == q1d*A.x + q2d*A.y + q3d*A.z assert v5.dt(N) == (-q2*q3d + q1d)*A.x + (q1*q3d + q2d)*A.y + q3d*A.z assert v3.diff(q1d, N) == 0 assert v3.diff(q2d, N) == A.x - q3 * cos(q3) * N.z assert v3.diff(q3d, N) == q3 * N.x + N.y assert v3.diff(q1d, A) == 0 assert v3.diff(q2d, A) == A.x - q3 * cos(q3) * N.z assert v3.diff(q3d, A) == q3 * N.x + N.y assert v3.diff(q1d, B) == 0 assert v3.diff(q2d, B) == A.x - q3 * cos(q3) * N.z assert v3.diff(q3d, B) == q3 * N.x + N.y assert v4.diff(q1d, N) == 0 assert v4.diff(q2d, N) == A.x - q3 * cos(q3) * N.z assert v4.diff(q3d, N) == B.x + q3 * N.x + N.y assert v4.diff(q1d, A) == 0 assert v4.diff(q2d, A) == A.x - q3 * cos(q3) * N.z assert v4.diff(q3d, A) == B.x + q3 * N.x + N.y assert v4.diff(q1d, B) == 0 assert v4.diff(q2d, B) == A.x - q3 * cos(q3) * N.z assert v4.diff(q3d, B) == B.x + q3 * N.x + N.y def test_vector_var_in_dcm(): N = ReferenceFrame('N') A = ReferenceFrame('A') B = ReferenceFrame('B') u1, u2, u3, u4 = dynamicsymbols('u1 u2 u3 u4') v = u1 * u2 * A.x + u3 * N.y + u4**2 * N.z assert v.diff(u1, N, var_in_dcm=False) == u2 * A.x assert v.diff(u1, A, var_in_dcm=False) == u2 * A.x assert v.diff(u3, N, var_in_dcm=False) == N.y assert v.diff(u3, A, var_in_dcm=False) == N.y assert v.diff(u3, B, var_in_dcm=False) == N.y assert v.diff(u4, N, var_in_dcm=False) == 2 * u4 * N.z raises(ValueError, lambda: v.diff(u1, N)) def test_vector_simplify(): x, y, z, k, n, m, w, f, s, A = symbols('x, y, z, k, n, m, w, f, s, A') N = ReferenceFrame('N') test1 = (1 / x + 1 / y) * N.x assert (test1 & N.x) != (x + y) / (x * y) test1 = test1.simplify() assert (test1 & N.x) == (x + y) / (x * y) test2 = (A**2 * s**4 / (4 * pi * k * m**3)) * N.x test2 = test2.simplify() assert (test2 & N.x) == (A**2 * s**4 / (4 * pi * k * m**3)) test3 = ((4 + 4 * x - 2 * (2 + 2 * x)) / (2 + 2 * x)) * N.x test3 = test3.simplify() assert (test3 & N.x) == 0 test4 = ((-4 * x * y**2 - 2 * y**3 - 2 * x**2 * y) / (x + y)**2) * N.x test4 = test4.simplify() assert (test4 & N.x) == -2 * y def test_vector_evalf(): a, b = symbols('a b') v = pi * A.x assert v.evalf(2) == Float('3.1416', 2) * A.x v = pi * A.x + 5 * a * A.y - b * A.z assert v.evalf(3) == Float('3.1416', 3) * A.x + Float('5', 3) * a * A.y - b * A.z assert v.evalf(5, subs={a: 1.234, b:5.8973}) == Float('3.1415926536', 5) * A.x + Float('6.17', 5) * A.y - Float('5.8973', 5) * A.z def test_vector_angle(): A = ReferenceFrame('A') v1 = A.x + A.y v2 = A.z assert v1.angle_between(v2) == pi/2 B = ReferenceFrame('B') B.orient_axis(A, A.x, pi) v3 = A.x v4 = B.x assert v3.angle_between(v4) == 0 def test_vector_xreplace(): x, y, z = symbols('x y z') v = x**2 * A.x + x*y * A.y + x*y*z * A.z assert v.xreplace({x : cos(x)}) == cos(x)**2 * A.x + y*cos(x) * A.y + y*z*cos(x) * A.z assert v.xreplace({x*y : pi}) == x**2 * A.x + pi * A.y + x*y*z * A.z assert v.xreplace({x*y*z : 1}) == x**2*A.x + x*y*A.y + A.z assert v.xreplace({x:1, z:0}) == A.x + y * A.y raises(TypeError, lambda: v.xreplace()) raises(TypeError, lambda: v.xreplace([x, y]))
22920a0673914a5fbca39f01e6b58e1650a529c3fc8deb265ede2dbb9eaccd23
from sympy import (S, Dummy, Lambda, symbols, Interval, Intersection, Set, EmptySet, FiniteSet, Union, ComplexRegion, Mul) from sympy.multipledispatch import dispatch from sympy.sets.conditionset import ConditionSet from sympy.sets.fancysets import (Integers, Naturals, Reals, Range, ImageSet, Rationals) from sympy.sets.sets import UniversalSet, imageset, ProductSet from sympy.simplify.radsimp import numer @dispatch(ConditionSet, ConditionSet) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 return None @dispatch(ConditionSet, Set) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 return ConditionSet(a.sym, a.condition, Intersection(a.base_set, b)) @dispatch(Naturals, Integers) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 return a @dispatch(Naturals, Naturals) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 return a if a is S.Naturals else b @dispatch(Interval, Naturals) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 return intersection_sets(b, a) @dispatch(ComplexRegion, Set) # type: ignore # noqa:F811 def intersection_sets(self, other): # noqa:F811 if other.is_ComplexRegion: # self in rectangular form if (not self.polar) and (not other.polar): return ComplexRegion(Intersection(self.sets, other.sets)) # self in polar form elif self.polar and other.polar: r1, theta1 = self.a_interval, self.b_interval r2, theta2 = other.a_interval, other.b_interval new_r_interval = Intersection(r1, r2) new_theta_interval = Intersection(theta1, theta2) # 0 and 2*Pi means the same if ((2*S.Pi in theta1 and S.Zero in theta2) or (2*S.Pi in theta2 and S.Zero in theta1)): new_theta_interval = Union(new_theta_interval, FiniteSet(0)) return ComplexRegion(new_r_interval*new_theta_interval, polar=True) if other.is_subset(S.Reals): new_interval = [] x = symbols("x", cls=Dummy, real=True) # self in rectangular form if not self.polar: for element in self.psets: if S.Zero in element.args[1]: new_interval.append(element.args[0]) new_interval = Union(*new_interval) return Intersection(new_interval, other) # self in polar form elif self.polar: for element in self.psets: if S.Zero in element.args[1]: new_interval.append(element.args[0]) if S.Pi in element.args[1]: new_interval.append(ImageSet(Lambda(x, -x), element.args[0])) if S.Zero in element.args[0]: new_interval.append(FiniteSet(0)) new_interval = Union(*new_interval) return Intersection(new_interval, other) @dispatch(Integers, Reals) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 return a @dispatch(Range, Interval) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 from sympy.functions.elementary.integers import floor, ceiling if not all(i.is_number for i in b.args[:2]): return # In case of null Range, return an EmptySet. if a.size == 0: return S.EmptySet # trim down to self's size, and represent # as a Range with step 1. start = ceiling(max(b.inf, a.inf)) if start not in b: start += 1 end = floor(min(b.sup, a.sup)) if end not in b: end -= 1 return intersection_sets(a, Range(start, end + 1)) @dispatch(Range, Naturals) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 return intersection_sets(a, Interval(b.inf, S.Infinity)) @dispatch(Range, Range) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 from sympy.solvers.diophantine.diophantine import diop_linear from sympy.core.numbers import ilcm from sympy import sign # non-overlap quick exits if not b: return S.EmptySet if not a: return S.EmptySet if b.sup < a.inf: return S.EmptySet if b.inf > a.sup: return S.EmptySet # work with finite end at the start r1 = a if r1.start.is_infinite: r1 = r1.reversed r2 = b if r2.start.is_infinite: r2 = r2.reversed # If both ends are infinite then it means that one Range is just the set # of all integers (the step must be 1). if r1.start.is_infinite: return b if r2.start.is_infinite: return a # this equation represents the values of the Range; # it's a linear equation eq = lambda r, i: r.start + i*r.step # we want to know when the two equations might # have integer solutions so we use the diophantine # solver va, vb = diop_linear(eq(r1, Dummy('a')) - eq(r2, Dummy('b'))) # check for no solution no_solution = va is None and vb is None if no_solution: return S.EmptySet # there is a solution # ------------------- # find the coincident point, c a0 = va.as_coeff_Add()[0] c = eq(r1, a0) # find the first point, if possible, in each range # since c may not be that point def _first_finite_point(r1, c): if c == r1.start: return c # st is the signed step we need to take to # get from c to r1.start st = sign(r1.start - c)*step # use Range to calculate the first point: # we want to get as close as possible to # r1.start; the Range will not be null since # it will at least contain c s1 = Range(c, r1.start + st, st)[-1] if s1 == r1.start: pass else: # if we didn't hit r1.start then, if the # sign of st didn't match the sign of r1.step # we are off by one and s1 is not in r1 if sign(r1.step) != sign(st): s1 -= st if s1 not in r1: return return s1 # calculate the step size of the new Range step = abs(ilcm(r1.step, r2.step)) s1 = _first_finite_point(r1, c) if s1 is None: return S.EmptySet s2 = _first_finite_point(r2, c) if s2 is None: return S.EmptySet # replace the corresponding start or stop in # the original Ranges with these points; the # result must have at least one point since # we know that s1 and s2 are in the Ranges def _updated_range(r, first): st = sign(r.step)*step if r.start.is_finite: rv = Range(first, r.stop, st) else: rv = Range(r.start, first + st, st) return rv r1 = _updated_range(a, s1) r2 = _updated_range(b, s2) # work with them both in the increasing direction if sign(r1.step) < 0: r1 = r1.reversed if sign(r2.step) < 0: r2 = r2.reversed # return clipped Range with positive step; it # can't be empty at this point start = max(r1.start, r2.start) stop = min(r1.stop, r2.stop) return Range(start, stop, step) @dispatch(Range, Integers) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 return a @dispatch(ImageSet, Set) # type: ignore # noqa:F811 def intersection_sets(self, other): # noqa:F811 from sympy.solvers.diophantine import diophantine # Only handle the straight-forward univariate case if (len(self.lamda.variables) > 1 or self.lamda.signature != self.lamda.variables): return None base_set = self.base_sets[0] # Intersection between ImageSets with Integers as base set # For {f(n) : n in Integers} & {g(m) : m in Integers} we solve the # diophantine equations f(n)=g(m). # If the solutions for n are {h(t) : t in Integers} then we return # {f(h(t)) : t in integers}. # If the solutions for n are {n_1, n_2, ..., n_k} then we return # {f(n_i) : 1 <= i <= k}. if base_set is S.Integers: gm = None if isinstance(other, ImageSet) and other.base_sets == (S.Integers,): gm = other.lamda.expr var = other.lamda.variables[0] # Symbol of second ImageSet lambda must be distinct from first m = Dummy('m') gm = gm.subs(var, m) elif other is S.Integers: m = gm = Dummy('m') if gm is not None: fn = self.lamda.expr n = self.lamda.variables[0] try: solns = list(diophantine(fn - gm, syms=(n, m), permute=True)) except (TypeError, NotImplementedError): # TypeError if equation not polynomial with rational coeff. # NotImplementedError if correct format but no solver. return # 3 cases are possible for solns: # - empty set, # - one or more parametric (infinite) solutions, # - a finite number of (non-parametric) solution couples. # Among those, there is one type of solution set that is # not helpful here: multiple parametric solutions. if len(solns) == 0: return EmptySet elif any(not isinstance(s, int) and s.free_symbols for tupl in solns for s in tupl): if len(solns) == 1: soln, solm = solns[0] (t,) = soln.free_symbols expr = fn.subs(n, soln.subs(t, n)).expand() return imageset(Lambda(n, expr), S.Integers) else: return else: return FiniteSet(*(fn.subs(n, s[0]) for s in solns)) if other == S.Reals: from sympy.core.function import expand_complex from sympy.solvers.solvers import denoms, solve_linear from sympy.core.relational import Eq def _solution_union(exprs, sym): # return a union of linear solutions to i in expr; # if i cannot be solved, use a ConditionSet for solution sols = [] for i in exprs: x, xis = solve_linear(i, 0, [sym]) if x == sym: sols.append(FiniteSet(xis)) else: sols.append(ConditionSet(sym, Eq(i, 0))) return Union(*sols) f = self.lamda.expr n = self.lamda.variables[0] n_ = Dummy(n.name, real=True) f_ = f.subs(n, n_) re, im = f_.as_real_imag() im = expand_complex(im) re = re.subs(n_, n) im = im.subs(n_, n) ifree = im.free_symbols lam = Lambda(n, re) if im.is_zero: # allow re-evaluation # of self in this case to make # the result canonical pass elif im.is_zero is False: return S.EmptySet elif ifree != {n}: return None else: # univarite imaginary part in same variable; # use numer instead of as_numer_denom to keep # this as fast as possible while still handling # simple cases base_set &= _solution_union( Mul.make_args(numer(im)), n) # exclude values that make denominators 0 base_set -= _solution_union(denoms(f), n) return imageset(lam, base_set) elif isinstance(other, Interval): from sympy.solvers.solveset import (invert_real, invert_complex, solveset) f = self.lamda.expr n = self.lamda.variables[0] new_inf, new_sup = None, None new_lopen, new_ropen = other.left_open, other.right_open if f.is_real: inverter = invert_real else: inverter = invert_complex g1, h1 = inverter(f, other.inf, n) g2, h2 = inverter(f, other.sup, n) if all(isinstance(i, FiniteSet) for i in (h1, h2)): if g1 == n: if len(h1) == 1: new_inf = h1.args[0] if g2 == n: if len(h2) == 1: new_sup = h2.args[0] # TODO: Design a technique to handle multiple-inverse # functions # Any of the new boundary values cannot be determined if any(i is None for i in (new_sup, new_inf)): return range_set = S.EmptySet if all(i.is_real for i in (new_sup, new_inf)): # this assumes continuity of underlying function # however fixes the case when it is decreasing if new_inf > new_sup: new_inf, new_sup = new_sup, new_inf new_interval = Interval(new_inf, new_sup, new_lopen, new_ropen) range_set = base_set.intersect(new_interval) else: if other.is_subset(S.Reals): solutions = solveset(f, n, S.Reals) if not isinstance(range_set, (ImageSet, ConditionSet)): range_set = solutions.intersect(other) else: return if range_set is S.EmptySet: return S.EmptySet elif isinstance(range_set, Range) and range_set.size is not S.Infinity: range_set = FiniteSet(*list(range_set)) if range_set is not None: return imageset(Lambda(n, f), range_set) return else: return @dispatch(ProductSet, ProductSet) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 if len(b.args) != len(a.args): return S.EmptySet return ProductSet(*(i.intersect(j) for i, j in zip(a.sets, b.sets))) @dispatch(Interval, Interval) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 # handle (-oo, oo) infty = S.NegativeInfinity, S.Infinity if a == Interval(*infty): l, r = a.left, a.right if l.is_real or l in infty or r.is_real or r in infty: return b # We can't intersect [0,3] with [x,6] -- we don't know if x>0 or x<0 if not a._is_comparable(b): return None empty = False if a.start <= b.end and b.start <= a.end: # Get topology right. if a.start < b.start: start = b.start left_open = b.left_open elif a.start > b.start: start = a.start left_open = a.left_open else: start = a.start left_open = a.left_open or b.left_open if a.end < b.end: end = a.end right_open = a.right_open elif a.end > b.end: end = b.end right_open = b.right_open else: end = a.end right_open = a.right_open or b.right_open if end - start == 0 and (left_open or right_open): empty = True else: empty = True if empty: return S.EmptySet return Interval(start, end, left_open, right_open) @dispatch(type(EmptySet), Set) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 return S.EmptySet @dispatch(UniversalSet, Set) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 return b @dispatch(FiniteSet, FiniteSet) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 return FiniteSet(*(a._elements & b._elements)) @dispatch(FiniteSet, Set) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 try: return FiniteSet(*[el for el in a if el in b]) except TypeError: return None # could not evaluate `el in b` due to symbolic ranges. @dispatch(Set, Set) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 return None @dispatch(Integers, Rationals) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 return a @dispatch(Naturals, Rationals) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 return a @dispatch(Rationals, Reals) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 return a def _intlike_interval(a, b): try: from sympy.functions.elementary.integers import floor, ceiling if b._inf is S.NegativeInfinity and b._sup is S.Infinity: return a s = Range(max(a.inf, ceiling(b.left)), floor(b.right) + 1) return intersection_sets(s, b) # take out endpoints if open interval except ValueError: return None @dispatch(Integers, Interval) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 return _intlike_interval(a, b) @dispatch(Naturals, Interval) # type: ignore # noqa:F811 def intersection_sets(a, b): # noqa:F811 return _intlike_interval(a, b)
df67cb5958d56936ac2c410a14ea4bb7809a2e91e2ddd8e486aa5206dc78e42e
from sympy.core.expr import unchanged from sympy.sets.fancysets import (ImageSet, Range, normalize_theta_set, ComplexRegion) from sympy.sets.sets import (FiniteSet, Interval, Union, imageset, Intersection, ProductSet, Contains) from sympy.sets.conditionset import ConditionSet from sympy.simplify.simplify import simplify from sympy import (S, Symbol, Lambda, symbols, cos, sin, pi, oo, Basic, Rational, sqrt, tan, log, exp, Abs, I, Tuple, eye, Dummy, floor, And, Eq) from sympy.utilities.iterables import cartes from sympy.testing.pytest import XFAIL, raises from sympy.abc import x, y, t, z from sympy.core.mod import Mod import itertools def test_naturals(): N = S.Naturals assert 5 in N assert -5 not in N assert 5.5 not in N ni = iter(N) a, b, c, d = next(ni), next(ni), next(ni), next(ni) assert (a, b, c, d) == (1, 2, 3, 4) assert isinstance(a, Basic) assert N.intersect(Interval(-5, 5)) == Range(1, 6) assert N.intersect(Interval(-5, 5, True, True)) == Range(1, 5) assert N.boundary == N assert N.is_open == False assert N.is_closed == True assert N.inf == 1 assert N.sup is oo assert not N.contains(oo) for s in (S.Naturals0, S.Naturals): assert s.intersection(S.Reals) is s assert s.is_subset(S.Reals) assert N.as_relational(x) == And(Eq(floor(x), x), x >= 1, x < oo) def test_naturals0(): N = S.Naturals0 assert 0 in N assert -1 not in N assert next(iter(N)) == 0 assert not N.contains(oo) assert N.contains(sin(x)) == Contains(sin(x), N) def test_integers(): Z = S.Integers assert 5 in Z assert -5 in Z assert 5.5 not in Z assert not Z.contains(oo) assert not Z.contains(-oo) zi = iter(Z) a, b, c, d = next(zi), next(zi), next(zi), next(zi) assert (a, b, c, d) == (0, 1, -1, 2) assert isinstance(a, Basic) assert Z.intersect(Interval(-5, 5)) == Range(-5, 6) assert Z.intersect(Interval(-5, 5, True, True)) == Range(-4, 5) assert Z.intersect(Interval(5, S.Infinity)) == Range(5, S.Infinity) assert Z.intersect(Interval.Lopen(5, S.Infinity)) == Range(6, S.Infinity) assert Z.inf is -oo assert Z.sup is oo assert Z.boundary == Z assert Z.is_open == False assert Z.is_closed == True assert Z.as_relational(x) == And(Eq(floor(x), x), -oo < x, x < oo) def test_ImageSet(): raises(ValueError, lambda: ImageSet(x, S.Integers)) assert ImageSet(Lambda(x, 1), S.Integers) == FiniteSet(1) assert ImageSet(Lambda(x, y), S.Integers) == {y} assert ImageSet(Lambda(x, 1), S.EmptySet) == S.EmptySet empty = Intersection(FiniteSet(log(2)/pi), S.Integers) assert unchanged(ImageSet, Lambda(x, 1), empty) # issue #17471 squares = ImageSet(Lambda(x, x**2), S.Naturals) assert 4 in squares assert 5 not in squares assert FiniteSet(*range(10)).intersect(squares) == FiniteSet(1, 4, 9) assert 16 not in squares.intersect(Interval(0, 10)) si = iter(squares) a, b, c, d = next(si), next(si), next(si), next(si) assert (a, b, c, d) == (1, 4, 9, 16) harmonics = ImageSet(Lambda(x, 1/x), S.Naturals) assert Rational(1, 5) in harmonics assert Rational(.25) in harmonics assert 0.25 not in harmonics assert Rational(.3) not in harmonics assert (1, 2) not in harmonics assert harmonics.is_iterable assert imageset(x, -x, Interval(0, 1)) == Interval(-1, 0) assert ImageSet(Lambda(x, x**2), Interval(0, 2)).doit() == Interval(0, 4) assert ImageSet(Lambda((x, y), 2*x), {4}, {3}).doit() == FiniteSet(8) assert (ImageSet(Lambda((x, y), x+y), {1, 2, 3}, {10, 20, 30}).doit() == FiniteSet(11, 12, 13, 21, 22, 23, 31, 32, 33)) c = Interval(1, 3) * Interval(1, 3) assert Tuple(2, 6) in ImageSet(Lambda(((x, y),), (x, 2*y)), c) assert Tuple(2, S.Half) in ImageSet(Lambda(((x, y),), (x, 1/y)), c) assert Tuple(2, -2) not in ImageSet(Lambda(((x, y),), (x, y**2)), c) assert Tuple(2, -2) in ImageSet(Lambda(((x, y),), (x, -2)), c) c3 = ProductSet(Interval(3, 7), Interval(8, 11), Interval(5, 9)) assert Tuple(8, 3, 9) in ImageSet(Lambda(((t, y, x),), (y, t, x)), c3) assert Tuple(Rational(1, 8), 3, 9) in ImageSet(Lambda(((t, y, x),), (1/y, t, x)), c3) assert 2/pi not in ImageSet(Lambda(((x, y),), 2/x), c) assert 2/S(100) not in ImageSet(Lambda(((x, y),), 2/x), c) assert Rational(2, 3) in ImageSet(Lambda(((x, y),), 2/x), c) S1 = imageset(lambda x, y: x + y, S.Integers, S.Naturals) assert S1.base_pset == ProductSet(S.Integers, S.Naturals) assert S1.base_sets == (S.Integers, S.Naturals) # Passing a set instead of a FiniteSet shouldn't raise assert unchanged(ImageSet, Lambda(x, x**2), {1, 2, 3}) S2 = ImageSet(Lambda(((x, y),), x+y), {(1, 2), (3, 4)}) assert 3 in S2.doit() # FIXME: This doesn't yet work: #assert 3 in S2 assert S2._contains(3) is None raises(TypeError, lambda: ImageSet(Lambda(x, x**2), 1)) def test_image_is_ImageSet(): assert isinstance(imageset(x, sqrt(sin(x)), Range(5)), ImageSet) def test_halfcircle(): r, th = symbols('r, theta', real=True) L = Lambda(((r, th),), (r*cos(th), r*sin(th))) halfcircle = ImageSet(L, Interval(0, 1)*Interval(0, pi)) assert (1, 0) in halfcircle assert (0, -1) not in halfcircle assert (0, 0) in halfcircle assert halfcircle._contains((r, 0)) is None # This one doesn't work: #assert (r, 2*pi) not in halfcircle assert not halfcircle.is_iterable def test_ImageSet_iterator_not_injective(): L = Lambda(x, x - x % 2) # produces 0, 2, 2, 4, 4, 6, 6, ... evens = ImageSet(L, S.Naturals) i = iter(evens) # No repeats here assert (next(i), next(i), next(i), next(i)) == (0, 2, 4, 6) def test_inf_Range_len(): raises(ValueError, lambda: len(Range(0, oo, 2))) assert Range(0, oo, 2).size is S.Infinity assert Range(0, -oo, -2).size is S.Infinity assert Range(oo, 0, -2).size is S.Infinity assert Range(-oo, 0, 2).size is S.Infinity def test_Range_set(): empty = Range(0) assert Range(5) == Range(0, 5) == Range(0, 5, 1) r = Range(10, 20, 2) assert 12 in r assert 8 not in r assert 11 not in r assert 30 not in r assert list(Range(0, 5)) == list(range(5)) assert list(Range(5, 0, -1)) == list(range(5, 0, -1)) assert Range(5, 15).sup == 14 assert Range(5, 15).inf == 5 assert Range(15, 5, -1).sup == 15 assert Range(15, 5, -1).inf == 6 assert Range(10, 67, 10).sup == 60 assert Range(60, 7, -10).inf == 10 assert len(Range(10, 38, 10)) == 3 assert Range(0, 0, 5) == empty assert Range(oo, oo, 1) == empty assert Range(oo, 1, 1) == empty assert Range(-oo, 1, -1) == empty assert Range(1, oo, -1) == empty assert Range(1, -oo, 1) == empty assert Range(1, -4, oo) == empty ip = symbols('ip', positive=True) assert Range(0, ip, -1) == empty assert Range(0, -ip, 1) == empty assert Range(1, -4, -oo) == Range(1, 2) assert Range(1, 4, oo) == Range(1, 2) assert Range(-oo, oo).size == oo assert Range(oo, -oo, -1).size == oo raises(ValueError, lambda: Range(-oo, oo, 2)) raises(ValueError, lambda: Range(x, pi, y)) raises(ValueError, lambda: Range(x, y, 0)) assert 5 in Range(0, oo, 5) assert -5 in Range(-oo, 0, 5) assert oo not in Range(0, oo) ni = symbols('ni', integer=False) assert ni not in Range(oo) u = symbols('u', integer=None) assert Range(oo).contains(u) is not False inf = symbols('inf', infinite=True) assert inf not in Range(-oo, oo) raises(ValueError, lambda: Range(0, oo, 2)[-1]) raises(ValueError, lambda: Range(0, -oo, -2)[-1]) assert Range(-oo, 1, 1)[-1] is S.Zero assert Range(oo, 1, -1)[-1] == 2 assert inf not in Range(oo) assert Range(1, 10, 1)[-1] == 9 assert all(i.is_Integer for i in Range(0, -1, 1)) it = iter(Range(-oo, 0, 2)) raises(TypeError, lambda: next(it)) assert empty.intersect(S.Integers) == empty assert Range(-1, 10, 1).intersect(S.Integers) == Range(-1, 10, 1) assert Range(-1, 10, 1).intersect(S.Naturals) == Range(1, 10, 1) assert Range(-1, 10, 1).intersect(S.Naturals0) == Range(0, 10, 1) # test slicing assert Range(1, 10, 1)[5] == 6 assert Range(1, 12, 2)[5] == 11 assert Range(1, 10, 1)[-1] == 9 assert Range(1, 10, 3)[-1] == 7 raises(ValueError, lambda: Range(oo,0,-1)[1:3:0]) raises(ValueError, lambda: Range(oo,0,-1)[:1]) raises(ValueError, lambda: Range(1, oo)[-2]) raises(ValueError, lambda: Range(-oo, 1)[2]) raises(IndexError, lambda: Range(10)[-20]) raises(IndexError, lambda: Range(10)[20]) raises(ValueError, lambda: Range(2, -oo, -2)[2:2:0]) assert Range(2, -oo, -2)[2:2:2] == empty assert Range(2, -oo, -2)[:2:2] == Range(2, -2, -4) raises(ValueError, lambda: Range(-oo, 4, 2)[:2:2]) assert Range(-oo, 4, 2)[::-2] == Range(2, -oo, -4) raises(ValueError, lambda: Range(-oo, 4, 2)[::2]) assert Range(oo, 2, -2)[::] == Range(oo, 2, -2) assert Range(-oo, 4, 2)[:-2:-2] == Range(2, 0, -4) assert Range(-oo, 4, 2)[:-2:2] == Range(-oo, 0, 4) raises(ValueError, lambda: Range(-oo, 4, 2)[:0:-2]) raises(ValueError, lambda: Range(-oo, 4, 2)[:2:-2]) assert Range(-oo, 4, 2)[-2::-2] == Range(0, -oo, -4) raises(ValueError, lambda: Range(-oo, 4, 2)[-2:0:-2]) raises(ValueError, lambda: Range(-oo, 4, 2)[0::2]) assert Range(oo, 2, -2)[0::] == Range(oo, 2, -2) raises(ValueError, lambda: Range(-oo, 4, 2)[0:-2:2]) assert Range(oo, 2, -2)[0:-2:] == Range(oo, 6, -2) raises(ValueError, lambda: Range(oo, 2, -2)[0:2:]) raises(ValueError, lambda: Range(-oo, 4, 2)[2::-1]) assert Range(-oo, 4, 2)[-2::2] == Range(0, 4, 4) assert Range(oo, 0, -2)[-10:0:2] == empty raises(ValueError, lambda: Range(oo, 0, -2)[0]) raises(ValueError, lambda: Range(oo, 0, -2)[-10:10:2]) raises(ValueError, lambda: Range(oo, 0, -2)[0::-2]) assert Range(oo, 0, -2)[0:-4:-2] == empty assert Range(oo, 0, -2)[:0:2] == empty raises(ValueError, lambda: Range(oo, 0, -2)[:1:-1]) # test empty Range assert Range(x, x, y) == empty assert empty.reversed == empty assert 0 not in empty assert list(empty) == [] assert len(empty) == 0 assert empty.size is S.Zero assert empty.intersect(FiniteSet(0)) is S.EmptySet assert bool(empty) is False raises(IndexError, lambda: empty[0]) assert empty[:0] == empty raises(NotImplementedError, lambda: empty.inf) raises(NotImplementedError, lambda: empty.sup) assert empty.as_relational(x) is S.false AB = [None] + list(range(12)) for R in [ Range(1, 10), Range(1, 10, 2), ]: r = list(R) for a, b, c in cartes(AB, AB, [-3, -1, None, 1, 3]): for reverse in range(2): r = list(reversed(r)) R = R.reversed result = list(R[a:b:c]) ans = r[a:b:c] txt = ('\n%s[%s:%s:%s] = %s -> %s' % ( R, a, b, c, result, ans)) check = ans == result assert check, txt assert Range(1, 10, 1).boundary == Range(1, 10, 1) for r in (Range(1, 10, 2), Range(1, oo, 2)): rev = r.reversed assert r.inf == rev.inf and r.sup == rev.sup assert r.step == -rev.step builtin_range = range raises(TypeError, lambda: Range(builtin_range(1))) assert S(builtin_range(10)) == Range(10) assert S(builtin_range(1000000000000)) == Range(1000000000000) # test Range.as_relational assert Range(1, 4).as_relational(x) == (x >= 1) & (x <= 3) & Eq(Mod(x, 1), 0) assert Range(oo, 1, -2).as_relational(x) == (x >= 3) & (x < oo) & Eq(Mod(x + 1, -2), 0) def test_Range_symbolic(): # symbolic Range xr = Range(x, x + 4, 5) sr = Range(x, y, t) i = Symbol('i', integer=True) ip = Symbol('i', integer=True, positive=True) ipr = Range(ip) inr = Range(0, -ip, -1) ir = Range(i, i + 19, 2) ir2 = Range(i, i*8, 3*i) i = Symbol('i', integer=True) inf = symbols('inf', infinite=True) raises(ValueError, lambda: Range(inf)) raises(ValueError, lambda: Range(inf, 0, -1)) raises(ValueError, lambda: Range(inf, inf, 1)) raises(ValueError, lambda: Range(1, 1, inf)) # args assert xr.args == (x, x + 5, 5) assert sr.args == (x, y, t) assert ir.args == (i, i + 20, 2) assert ir2.args == (i, 10*i, 3*i) # reversed raises(ValueError, lambda: xr.reversed) raises(ValueError, lambda: sr.reversed) assert ipr.reversed.args == (ip - 1, -1, -1) assert inr.reversed.args == (-ip + 1, 1, 1) assert ir.reversed.args == (i + 18, i - 2, -2) assert ir2.reversed.args == (7*i, -2*i, -3*i) # contains assert inf not in sr assert inf not in ir assert 0 in ipr assert 0 in inr raises(TypeError, lambda: 1 in ipr) raises(TypeError, lambda: -1 in inr) assert .1 not in sr assert .1 not in ir assert i + 1 not in ir assert i + 2 in ir raises(TypeError, lambda: x in xr) # XXX is this what contains is supposed to do? raises(TypeError, lambda: 1 in sr) # XXX is this what contains is supposed to do? # iter raises(ValueError, lambda: next(iter(xr))) raises(ValueError, lambda: next(iter(sr))) assert next(iter(ir)) == i assert next(iter(ir2)) == i assert sr.intersect(S.Integers) == sr assert sr.intersect(FiniteSet(x)) == Intersection({x}, sr) raises(ValueError, lambda: sr[:2]) raises(ValueError, lambda: xr[0]) raises(ValueError, lambda: sr[0]) # len assert len(ir) == ir.size == 10 assert len(ir2) == ir2.size == 3 raises(ValueError, lambda: len(xr)) raises(ValueError, lambda: xr.size) raises(ValueError, lambda: len(sr)) raises(ValueError, lambda: sr.size) # bool assert bool(Range(0)) == False assert bool(xr) assert bool(ir) assert bool(ipr) assert bool(inr) raises(ValueError, lambda: bool(sr)) raises(ValueError, lambda: bool(ir2)) # inf raises(ValueError, lambda: xr.inf) raises(ValueError, lambda: sr.inf) assert ipr.inf == 0 assert inr.inf == -ip + 1 assert ir.inf == i raises(ValueError, lambda: ir2.inf) # sup raises(ValueError, lambda: xr.sup) raises(ValueError, lambda: sr.sup) assert ipr.sup == ip - 1 assert inr.sup == 0 assert ir.inf == i raises(ValueError, lambda: ir2.sup) # getitem raises(ValueError, lambda: xr[0]) raises(ValueError, lambda: sr[0]) raises(ValueError, lambda: sr[-1]) raises(ValueError, lambda: sr[:2]) assert ir[:2] == Range(i, i + 4, 2) assert ir[0] == i assert ir[-2] == i + 16 assert ir[-1] == i + 18 assert ir2[:2] == Range(i, 7*i, 3*i) assert ir2[0] == i assert ir2[-2] == 4*i assert ir2[-1] == 7*i raises(ValueError, lambda: Range(i)[-1]) assert ipr[0] == ipr.inf == 0 assert ipr[-1] == ipr.sup == ip - 1 assert inr[0] == inr.sup == 0 assert inr[-1] == inr.inf == -ip + 1 raises(ValueError, lambda: ipr[-2]) assert ir.inf == i assert ir.sup == i + 18 raises(ValueError, lambda: Range(i).inf) # as_relational assert ir.as_relational(x) == ((x >= i) & (x <= i + 18) & Eq(Mod(-i + x, 2), 0)) assert ir2.as_relational(x) == Eq( Mod(-i + x, 3*i), 0) & (((x >= i) & (x <= 7*i) & (3*i >= 1)) | ((x <= i) & (x >= 7*i) & (3*i <= -1))) assert Range(i, i + 1).as_relational(x) == Eq(x, i) assert sr.as_relational(z) == Eq( Mod(t, 1), 0) & Eq(Mod(x, 1), 0) & Eq(Mod(-x + z, t), 0 ) & (((z >= x) & (z <= -t + y) & (t >= 1)) | ((z <= x) & (z >= -t + y) & (t <= -1))) assert xr.as_relational(z) == Eq(z, x) & Eq(Mod(x, 1), 0) # symbols can clash if user wants (but it must be integer) assert xr.as_relational(x) == Eq(Mod(x, 1), 0) # contains() for symbolic values (issue #18146) e = Symbol('e', integer=True, even=True) o = Symbol('o', integer=True, odd=True) assert Range(5).contains(i) == And(i >= 0, i <= 4) assert Range(1).contains(i) == Eq(i, 0) assert Range(-oo, 5, 1).contains(i) == (i <= 4) assert Range(-oo, oo).contains(i) == True assert Range(0, 8, 2).contains(i) == Contains(i, Range(0, 8, 2)) assert Range(0, 8, 2).contains(e) == And(e >= 0, e <= 6) assert Range(0, 8, 2).contains(2*i) == And(2*i >= 0, 2*i <= 6) assert Range(0, 8, 2).contains(o) == False assert Range(1, 9, 2).contains(e) == False assert Range(1, 9, 2).contains(o) == And(o >= 1, o <= 7) assert Range(8, 0, -2).contains(o) == False assert Range(9, 1, -2).contains(o) == And(o >= 3, o <= 9) assert Range(-oo, 8, 2).contains(i) == Contains(i, Range(-oo, 8, 2)) def test_range_range_intersection(): for a, b, r in [ (Range(0), Range(1), S.EmptySet), (Range(3), Range(4, oo), S.EmptySet), (Range(3), Range(-3, -1), S.EmptySet), (Range(1, 3), Range(0, 3), Range(1, 3)), (Range(1, 3), Range(1, 4), Range(1, 3)), (Range(1, oo, 2), Range(2, oo, 2), S.EmptySet), (Range(0, oo, 2), Range(oo), Range(0, oo, 2)), (Range(0, oo, 2), Range(100), Range(0, 100, 2)), (Range(2, oo, 2), Range(oo), Range(2, oo, 2)), (Range(0, oo, 2), Range(5, 6), S.EmptySet), (Range(2, 80, 1), Range(55, 71, 4), Range(55, 71, 4)), (Range(0, 6, 3), Range(-oo, 5, 3), S.EmptySet), (Range(0, oo, 2), Range(5, oo, 3), Range(8, oo, 6)), (Range(4, 6, 2), Range(2, 16, 7), S.EmptySet),]: assert a.intersect(b) == r assert a.intersect(b.reversed) == r assert a.reversed.intersect(b) == r assert a.reversed.intersect(b.reversed) == r a, b = b, a assert a.intersect(b) == r assert a.intersect(b.reversed) == r assert a.reversed.intersect(b) == r assert a.reversed.intersect(b.reversed) == r def test_range_interval_intersection(): p = symbols('p', positive=True) assert isinstance(Range(3).intersect(Interval(p, p + 2)), Intersection) assert Range(4).intersect(Interval(0, 3)) == Range(4) assert Range(4).intersect(Interval(-oo, oo)) == Range(4) assert Range(4).intersect(Interval(1, oo)) == Range(1, 4) assert Range(4).intersect(Interval(1.1, oo)) == Range(2, 4) assert Range(4).intersect(Interval(0.1, 3)) == Range(1, 4) assert Range(4).intersect(Interval(0.1, 3.1)) == Range(1, 4) assert Range(4).intersect(Interval.open(0, 3)) == Range(1, 3) assert Range(4).intersect(Interval.open(0.1, 0.5)) is S.EmptySet # Null Range intersections assert Range(0).intersect(Interval(0.2, 0.8)) is S.EmptySet assert Range(0).intersect(Interval(-oo, oo)) is S.EmptySet def test_range_is_finite_set(): assert Range(-100, 100).is_finite_set is True assert Range(2, oo).is_finite_set is False assert Range(-oo, 50).is_finite_set is False assert Range(-oo, oo).is_finite_set is False assert Range(oo, -oo).is_finite_set is True assert Range(0, 0).is_finite_set is True assert Range(oo, oo).is_finite_set is True assert Range(-oo, -oo).is_finite_set is True n = Symbol('n', integer=True) m = Symbol('m', integer=True) assert Range(n, n + 49).is_finite_set is True assert Range(n, 0).is_finite_set is True assert Range(-3, n + 7).is_finite_set is True assert Range(n, m).is_finite_set is True assert Range(n + m, m - n).is_finite_set is True assert Range(n, n + m + n).is_finite_set is True assert Range(n, oo).is_finite_set is False assert Range(-oo, n).is_finite_set is False # assert Range(n, -oo).is_finite_set is True # assert Range(oo, n).is_finite_set is True # Above tests fail due to a (potential) bug in sympy.sets.fancysets.Range.size (See issue #18999) def test_Integers_eval_imageset(): ans = ImageSet(Lambda(x, 2*x + Rational(3, 7)), S.Integers) im = imageset(Lambda(x, -2*x + Rational(3, 7)), S.Integers) assert im == ans im = imageset(Lambda(x, -2*x - Rational(11, 7)), S.Integers) assert im == ans y = Symbol('y') L = imageset(x, 2*x + y, S.Integers) assert y + 4 in L a, b, c = 0.092, 0.433, 0.341 assert a in imageset(x, a + c*x, S.Integers) assert b in imageset(x, b + c*x, S.Integers) _x = symbols('x', negative=True) eq = _x**2 - _x + 1 assert imageset(_x, eq, S.Integers).lamda.expr == _x**2 + _x + 1 eq = 3*_x - 1 assert imageset(_x, eq, S.Integers).lamda.expr == 3*_x + 2 assert imageset(x, (x, 1/x), S.Integers) == \ ImageSet(Lambda(x, (x, 1/x)), S.Integers) def test_Range_eval_imageset(): a, b, c = symbols('a b c') assert imageset(x, a*(x + b) + c, Range(3)) == \ imageset(x, a*x + a*b + c, Range(3)) eq = (x + 1)**2 assert imageset(x, eq, Range(3)).lamda.expr == eq eq = a*(x + b) + c r = Range(3, -3, -2) imset = imageset(x, eq, r) assert imset.lamda.expr != eq assert list(imset) == [eq.subs(x, i).expand() for i in list(r)] def test_fun(): assert (FiniteSet(*ImageSet(Lambda(x, sin(pi*x/4)), Range(-10, 11))) == FiniteSet(-1, -sqrt(2)/2, 0, sqrt(2)/2, 1)) def test_Reals(): assert 5 in S.Reals assert S.Pi in S.Reals assert -sqrt(2) in S.Reals assert (2, 5) not in S.Reals assert sqrt(-1) not in S.Reals assert S.Reals == Interval(-oo, oo) assert S.Reals != Interval(0, oo) assert S.Reals.is_subset(Interval(-oo, oo)) assert S.Reals.intersect(Range(-oo, oo)) == Range(-oo, oo) def test_Complex(): assert 5 in S.Complexes assert 5 + 4*I in S.Complexes assert S.Pi in S.Complexes assert -sqrt(2) in S.Complexes assert -I in S.Complexes assert sqrt(-1) in S.Complexes assert S.Complexes.intersect(S.Reals) == S.Reals assert S.Complexes.union(S.Reals) == S.Complexes assert S.Complexes == ComplexRegion(S.Reals*S.Reals) assert (S.Complexes == ComplexRegion(Interval(1, 2)*Interval(3, 4))) == False assert str(S.Complexes) == "S.Complexes" assert repr(S.Complexes) == "S.Complexes" def take(n, iterable): "Return first n items of the iterable as a list" return list(itertools.islice(iterable, n)) def test_intersections(): assert S.Integers.intersect(S.Reals) == S.Integers assert 5 in S.Integers.intersect(S.Reals) assert 5 in S.Integers.intersect(S.Reals) assert -5 not in S.Naturals.intersect(S.Reals) assert 5.5 not in S.Integers.intersect(S.Reals) assert 5 in S.Integers.intersect(Interval(3, oo)) assert -5 in S.Integers.intersect(Interval(-oo, 3)) assert all(x.is_Integer for x in take(10, S.Integers.intersect(Interval(3, oo)) )) def test_infinitely_indexed_set_1(): from sympy.abc import n, m, t assert imageset(Lambda(n, n), S.Integers) == imageset(Lambda(m, m), S.Integers) assert imageset(Lambda(n, 2*n), S.Integers).intersect( imageset(Lambda(m, 2*m + 1), S.Integers)) is S.EmptySet assert imageset(Lambda(n, 2*n), S.Integers).intersect( imageset(Lambda(n, 2*n + 1), S.Integers)) is S.EmptySet assert imageset(Lambda(m, 2*m), S.Integers).intersect( imageset(Lambda(n, 3*n), S.Integers)).dummy_eq( ImageSet(Lambda(t, 6*t), S.Integers)) assert imageset(x, x/2 + Rational(1, 3), S.Integers).intersect(S.Integers) is S.EmptySet assert imageset(x, x/2 + S.Half, S.Integers).intersect(S.Integers) is S.Integers # https://github.com/sympy/sympy/issues/17355 S53 = ImageSet(Lambda(n, 5*n + 3), S.Integers) assert S53.intersect(S.Integers) == S53 def test_infinitely_indexed_set_2(): from sympy.abc import n a = Symbol('a', integer=True) assert imageset(Lambda(n, n), S.Integers) == \ imageset(Lambda(n, n + a), S.Integers) assert imageset(Lambda(n, n + pi), S.Integers) == \ imageset(Lambda(n, n + a + pi), S.Integers) assert imageset(Lambda(n, n), S.Integers) == \ imageset(Lambda(n, -n + a), S.Integers) assert imageset(Lambda(n, -6*n), S.Integers) == \ ImageSet(Lambda(n, 6*n), S.Integers) assert imageset(Lambda(n, 2*n + pi), S.Integers) == \ ImageSet(Lambda(n, 2*n + pi - 2), S.Integers) def test_imageset_intersect_real(): from sympy import I from sympy.abc import n assert imageset(Lambda(n, n + (n - 1)*(n + 1)*I), S.Integers).intersect(S.Reals) == FiniteSet(-1, 1) im = (n - 1)*(n + S.Half) assert imageset(Lambda(n, n + im*I), S.Integers ).intersect(S.Reals) == FiniteSet(1) assert imageset(Lambda(n, n + im*(n + 1)*I), S.Naturals0 ).intersect(S.Reals) == FiniteSet(1) assert imageset(Lambda(n, n/2 + im.expand()*I), S.Integers ).intersect(S.Reals) == ImageSet(Lambda(x, x/2), ConditionSet( n, Eq(n**2 - n/2 - S(1)/2, 0), S.Integers)) assert imageset(Lambda(n, n/(1/n - 1) + im*(n + 1)*I), S.Integers ).intersect(S.Reals) == FiniteSet(S.Half) assert imageset(Lambda(n, n/(n - 6) + (n - 3)*(n + 1)*I/(2*n + 2)), S.Integers).intersect( S.Reals) == FiniteSet(-1) assert imageset(Lambda(n, n/(n**2 - 9) + (n - 3)*(n + 1)*I/(2*n + 2)), S.Integers).intersect( S.Reals) is S.EmptySet s = ImageSet( Lambda(n, -I*(I*(2*pi*n - pi/4) + log(Abs(sqrt(-I))))), S.Integers) # s is unevaluated, but after intersection the result # should be canonical assert s.intersect(S.Reals) == imageset( Lambda(n, 2*n*pi - pi/4), S.Integers) == ImageSet( Lambda(n, 2*pi*n + pi*Rational(7, 4)), S.Integers) def test_imageset_intersect_interval(): from sympy.abc import n f1 = ImageSet(Lambda(n, n*pi), S.Integers) f2 = ImageSet(Lambda(n, 2*n), Interval(0, pi)) f3 = ImageSet(Lambda(n, 2*n*pi + pi/2), S.Integers) # complex expressions f4 = ImageSet(Lambda(n, n*I*pi), S.Integers) f5 = ImageSet(Lambda(n, 2*I*n*pi + pi/2), S.Integers) # non-linear expressions f6 = ImageSet(Lambda(n, log(n)), S.Integers) f7 = ImageSet(Lambda(n, n**2), S.Integers) f8 = ImageSet(Lambda(n, Abs(n)), S.Integers) f9 = ImageSet(Lambda(n, exp(n)), S.Naturals0) assert f1.intersect(Interval(-1, 1)) == FiniteSet(0) assert f1.intersect(Interval(0, 2*pi, False, True)) == FiniteSet(0, pi) assert f2.intersect(Interval(1, 2)) == Interval(1, 2) assert f3.intersect(Interval(-1, 1)) == S.EmptySet assert f3.intersect(Interval(-5, 5)) == FiniteSet(pi*Rational(-3, 2), pi/2) assert f4.intersect(Interval(-1, 1)) == FiniteSet(0) assert f4.intersect(Interval(1, 2)) == S.EmptySet assert f5.intersect(Interval(0, 1)) == S.EmptySet assert f6.intersect(Interval(0, 1)) == FiniteSet(S.Zero, log(2)) assert f7.intersect(Interval(0, 10)) == Intersection(f7, Interval(0, 10)) assert f8.intersect(Interval(0, 2)) == Intersection(f8, Interval(0, 2)) assert f9.intersect(Interval(1, 2)) == Intersection(f9, Interval(1, 2)) def test_imageset_intersect_diophantine(): from sympy.abc import m, n # Check that same lambda variable for both ImageSets is handled correctly img1 = ImageSet(Lambda(n, 2*n + 1), S.Integers) img2 = ImageSet(Lambda(n, 4*n + 1), S.Integers) assert img1.intersect(img2) == img2 # Empty solution set returned by diophantine: assert ImageSet(Lambda(n, 2*n), S.Integers).intersect( ImageSet(Lambda(n, 2*n + 1), S.Integers)) == S.EmptySet # Check intersection with S.Integers: assert ImageSet(Lambda(n, 9/n + 20*n/3), S.Integers).intersect( S.Integers) == FiniteSet(-61, -23, 23, 61) # Single solution (2, 3) for diophantine solution: assert ImageSet(Lambda(n, (n - 2)**2), S.Integers).intersect( ImageSet(Lambda(n, -(n - 3)**2), S.Integers)) == FiniteSet(0) # Single parametric solution for diophantine solution: assert ImageSet(Lambda(n, n**2 + 5), S.Integers).intersect( ImageSet(Lambda(m, 2*m), S.Integers)).dummy_eq(ImageSet( Lambda(n, 4*n**2 + 4*n + 6), S.Integers)) # 4 non-parametric solution couples for dioph. equation: assert ImageSet(Lambda(n, n**2 - 9), S.Integers).intersect( ImageSet(Lambda(m, -m**2), S.Integers)) == FiniteSet(-9, 0) # Double parametric solution for diophantine solution: assert ImageSet(Lambda(m, m**2 + 40), S.Integers).intersect( ImageSet(Lambda(n, 41*n), S.Integers)).dummy_eq(Intersection( ImageSet(Lambda(m, m**2 + 40), S.Integers), ImageSet(Lambda(n, 41*n), S.Integers))) # Check that diophantine returns *all* (8) solutions (permute=True) assert ImageSet(Lambda(n, n**4 - 2**4), S.Integers).intersect( ImageSet(Lambda(m, -m**4 + 3**4), S.Integers)) == FiniteSet(0, 65) assert ImageSet(Lambda(n, pi/12 + n*5*pi/12), S.Integers).intersect( ImageSet(Lambda(n, 7*pi/12 + n*11*pi/12), S.Integers)).dummy_eq(ImageSet( Lambda(n, 55*pi*n/12 + 17*pi/4), S.Integers)) # TypeError raised by diophantine (#18081) assert ImageSet(Lambda(n, n*log(2)), S.Integers).intersection( S.Integers).dummy_eq(Intersection(ImageSet( Lambda(n, n*log(2)), S.Integers), S.Integers)) # NotImplementedError raised by diophantine (no solver for cubic_thue) assert ImageSet(Lambda(n, n**3 + 1), S.Integers).intersect( ImageSet(Lambda(n, n**3), S.Integers)).dummy_eq(Intersection( ImageSet(Lambda(n, n**3 + 1), S.Integers), ImageSet(Lambda(n, n**3), S.Integers))) def test_infinitely_indexed_set_3(): from sympy.abc import n, m, t assert imageset(Lambda(m, 2*pi*m), S.Integers).intersect( imageset(Lambda(n, 3*pi*n), S.Integers)).dummy_eq( ImageSet(Lambda(t, 6*pi*t), S.Integers)) assert imageset(Lambda(n, 2*n + 1), S.Integers) == \ imageset(Lambda(n, 2*n - 1), S.Integers) assert imageset(Lambda(n, 3*n + 2), S.Integers) == \ imageset(Lambda(n, 3*n - 1), S.Integers) def test_ImageSet_simplification(): from sympy.abc import n, m assert imageset(Lambda(n, n), S.Integers) == S.Integers assert imageset(Lambda(n, sin(n)), imageset(Lambda(m, tan(m)), S.Integers)) == \ imageset(Lambda(m, sin(tan(m))), S.Integers) assert imageset(n, 1 + 2*n, S.Naturals) == Range(3, oo, 2) assert imageset(n, 1 + 2*n, S.Naturals0) == Range(1, oo, 2) assert imageset(n, 1 - 2*n, S.Naturals) == Range(-1, -oo, -2) def test_ImageSet_contains(): from sympy.abc import x assert (2, S.Half) in imageset(x, (x, 1/x), S.Integers) assert imageset(x, x + I*3, S.Integers).intersection(S.Reals) is S.EmptySet i = Dummy(integer=True) q = imageset(x, x + I*y, S.Integers).intersection(S.Reals) assert q.subs(y, I*i).intersection(S.Integers) is S.Integers q = imageset(x, x + I*y/x, S.Integers).intersection(S.Reals) assert q.subs(y, 0) is S.Integers assert q.subs(y, I*i*x).intersection(S.Integers) is S.Integers z = cos(1)**2 + sin(1)**2 - 1 q = imageset(x, x + I*z, S.Integers).intersection(S.Reals) assert q is not S.EmptySet def test_ComplexRegion_contains(): r = Symbol('r', real=True) # contains in ComplexRegion a = Interval(2, 3) b = Interval(4, 6) c = Interval(7, 9) c1 = ComplexRegion(a*b) c2 = ComplexRegion(Union(a*b, c*a)) assert 2.5 + 4.5*I in c1 assert 2 + 4*I in c1 assert 3 + 4*I in c1 assert 8 + 2.5*I in c2 assert 2.5 + 6.1*I not in c1 assert 4.5 + 3.2*I not in c1 assert c1.contains(x) == Contains(x, c1, evaluate=False) assert c1.contains(r) == False assert c2.contains(x) == Contains(x, c2, evaluate=False) assert c2.contains(r) == False r1 = Interval(0, 1) theta1 = Interval(0, 2*S.Pi) c3 = ComplexRegion(r1*theta1, polar=True) assert (0.5 + I*Rational(6, 10)) in c3 assert (S.Half + I*Rational(6, 10)) in c3 assert (S.Half + .6*I) in c3 assert (0.5 + .6*I) in c3 assert I in c3 assert 1 in c3 assert 0 in c3 assert 1 + I not in c3 assert 1 - I not in c3 assert c3.contains(x) == Contains(x, c3, evaluate=False) assert c3.contains(r + 2*I) == Contains( r + 2*I, c3, evaluate=False) # is in fact False assert c3.contains(1/(1 + r**2)) == Contains( 1/(1 + r**2), c3, evaluate=False) # is in fact True r2 = Interval(0, 3) theta2 = Interval(pi, 2*pi, left_open=True) c4 = ComplexRegion(r2*theta2, polar=True) assert c4.contains(0) == True assert c4.contains(2 + I) == False assert c4.contains(-2 + I) == False assert c4.contains(-2 - I) == True assert c4.contains(2 - I) == True assert c4.contains(-2) == False assert c4.contains(2) == True assert c4.contains(x) == Contains(x, c4, evaluate=False) assert c4.contains(3/(1 + r**2)) == Contains( 3/(1 + r**2), c4, evaluate=False) # is in fact True raises(ValueError, lambda: ComplexRegion(r1*theta1, polar=2)) def test_ComplexRegion_intersect(): # Polar form X_axis = ComplexRegion(Interval(0, oo)*FiniteSet(0, S.Pi), polar=True) unit_disk = ComplexRegion(Interval(0, 1)*Interval(0, 2*S.Pi), polar=True) upper_half_unit_disk = ComplexRegion(Interval(0, 1)*Interval(0, S.Pi), polar=True) upper_half_disk = ComplexRegion(Interval(0, oo)*Interval(0, S.Pi), polar=True) lower_half_disk = ComplexRegion(Interval(0, oo)*Interval(S.Pi, 2*S.Pi), polar=True) right_half_disk = ComplexRegion(Interval(0, oo)*Interval(-S.Pi/2, S.Pi/2), polar=True) first_quad_disk = ComplexRegion(Interval(0, oo)*Interval(0, S.Pi/2), polar=True) assert upper_half_disk.intersect(unit_disk) == upper_half_unit_disk assert right_half_disk.intersect(first_quad_disk) == first_quad_disk assert upper_half_disk.intersect(right_half_disk) == first_quad_disk assert upper_half_disk.intersect(lower_half_disk) == X_axis c1 = ComplexRegion(Interval(0, 4)*Interval(0, 2*S.Pi), polar=True) assert c1.intersect(Interval(1, 5)) == Interval(1, 4) assert c1.intersect(Interval(4, 9)) == FiniteSet(4) assert c1.intersect(Interval(5, 12)) is S.EmptySet # Rectangular form X_axis = ComplexRegion(Interval(-oo, oo)*FiniteSet(0)) unit_square = ComplexRegion(Interval(-1, 1)*Interval(-1, 1)) upper_half_unit_square = ComplexRegion(Interval(-1, 1)*Interval(0, 1)) upper_half_plane = ComplexRegion(Interval(-oo, oo)*Interval(0, oo)) lower_half_plane = ComplexRegion(Interval(-oo, oo)*Interval(-oo, 0)) right_half_plane = ComplexRegion(Interval(0, oo)*Interval(-oo, oo)) first_quad_plane = ComplexRegion(Interval(0, oo)*Interval(0, oo)) assert upper_half_plane.intersect(unit_square) == upper_half_unit_square assert right_half_plane.intersect(first_quad_plane) == first_quad_plane assert upper_half_plane.intersect(right_half_plane) == first_quad_plane assert upper_half_plane.intersect(lower_half_plane) == X_axis c1 = ComplexRegion(Interval(-5, 5)*Interval(-10, 10)) assert c1.intersect(Interval(2, 7)) == Interval(2, 5) assert c1.intersect(Interval(5, 7)) == FiniteSet(5) assert c1.intersect(Interval(6, 9)) is S.EmptySet # unevaluated object C1 = ComplexRegion(Interval(0, 1)*Interval(0, 2*S.Pi), polar=True) C2 = ComplexRegion(Interval(-1, 1)*Interval(-1, 1)) assert C1.intersect(C2) == Intersection(C1, C2, evaluate=False) def test_ComplexRegion_union(): # Polar form c1 = ComplexRegion(Interval(0, 1)*Interval(0, 2*S.Pi), polar=True) c2 = ComplexRegion(Interval(0, 1)*Interval(0, S.Pi), polar=True) c3 = ComplexRegion(Interval(0, oo)*Interval(0, S.Pi), polar=True) c4 = ComplexRegion(Interval(0, oo)*Interval(S.Pi, 2*S.Pi), polar=True) p1 = Union(Interval(0, 1)*Interval(0, 2*S.Pi), Interval(0, 1)*Interval(0, S.Pi)) p2 = Union(Interval(0, oo)*Interval(0, S.Pi), Interval(0, oo)*Interval(S.Pi, 2*S.Pi)) assert c1.union(c2) == ComplexRegion(p1, polar=True) assert c3.union(c4) == ComplexRegion(p2, polar=True) # Rectangular form c5 = ComplexRegion(Interval(2, 5)*Interval(6, 9)) c6 = ComplexRegion(Interval(4, 6)*Interval(10, 12)) c7 = ComplexRegion(Interval(0, 10)*Interval(-10, 0)) c8 = ComplexRegion(Interval(12, 16)*Interval(14, 20)) p3 = Union(Interval(2, 5)*Interval(6, 9), Interval(4, 6)*Interval(10, 12)) p4 = Union(Interval(0, 10)*Interval(-10, 0), Interval(12, 16)*Interval(14, 20)) assert c5.union(c6) == ComplexRegion(p3) assert c7.union(c8) == ComplexRegion(p4) assert c1.union(Interval(2, 4)) == Union(c1, Interval(2, 4), evaluate=False) assert c5.union(Interval(2, 4)) == Union(c5, ComplexRegion.from_real(Interval(2, 4))) def test_ComplexRegion_from_real(): c1 = ComplexRegion(Interval(0, 1) * Interval(0, 2 * S.Pi), polar=True) raises(ValueError, lambda: c1.from_real(c1)) assert c1.from_real(Interval(-1, 1)) == ComplexRegion(Interval(-1, 1) * FiniteSet(0), False) def test_ComplexRegion_measure(): a, b = Interval(2, 5), Interval(4, 8) theta1, theta2 = Interval(0, 2*S.Pi), Interval(0, S.Pi) c1 = ComplexRegion(a*b) c2 = ComplexRegion(Union(a*theta1, b*theta2), polar=True) assert c1.measure == 12 assert c2.measure == 9*pi def test_normalize_theta_set(): # Interval assert normalize_theta_set(Interval(pi, 2*pi)) == \ Union(FiniteSet(0), Interval.Ropen(pi, 2*pi)) assert normalize_theta_set(Interval(pi*Rational(9, 2), 5*pi)) == Interval(pi/2, pi) assert normalize_theta_set(Interval(pi*Rational(-3, 2), pi/2)) == Interval.Ropen(0, 2*pi) assert normalize_theta_set(Interval.open(pi*Rational(-3, 2), pi/2)) == \ Union(Interval.Ropen(0, pi/2), Interval.open(pi/2, 2*pi)) assert normalize_theta_set(Interval.open(pi*Rational(-7, 2), pi*Rational(-3, 2))) == \ Union(Interval.Ropen(0, pi/2), Interval.open(pi/2, 2*pi)) assert normalize_theta_set(Interval(-pi/2, pi/2)) == \ Union(Interval(0, pi/2), Interval.Ropen(pi*Rational(3, 2), 2*pi)) assert normalize_theta_set(Interval.open(-pi/2, pi/2)) == \ Union(Interval.Ropen(0, pi/2), Interval.open(pi*Rational(3, 2), 2*pi)) assert normalize_theta_set(Interval(-4*pi, 3*pi)) == Interval.Ropen(0, 2*pi) assert normalize_theta_set(Interval(pi*Rational(-3, 2), -pi/2)) == Interval(pi/2, pi*Rational(3, 2)) assert normalize_theta_set(Interval.open(0, 2*pi)) == Interval.open(0, 2*pi) assert normalize_theta_set(Interval.Ropen(-pi/2, pi/2)) == \ Union(Interval.Ropen(0, pi/2), Interval.Ropen(pi*Rational(3, 2), 2*pi)) assert normalize_theta_set(Interval.Lopen(-pi/2, pi/2)) == \ Union(Interval(0, pi/2), Interval.open(pi*Rational(3, 2), 2*pi)) assert normalize_theta_set(Interval(-pi/2, pi/2)) == \ Union(Interval(0, pi/2), Interval.Ropen(pi*Rational(3, 2), 2*pi)) assert normalize_theta_set(Interval.open(4*pi, pi*Rational(9, 2))) == Interval.open(0, pi/2) assert normalize_theta_set(Interval.Lopen(4*pi, pi*Rational(9, 2))) == Interval.Lopen(0, pi/2) assert normalize_theta_set(Interval.Ropen(4*pi, pi*Rational(9, 2))) == Interval.Ropen(0, pi/2) assert normalize_theta_set(Interval.open(3*pi, 5*pi)) == \ Union(Interval.Ropen(0, pi), Interval.open(pi, 2*pi)) # FiniteSet assert normalize_theta_set(FiniteSet(0, pi, 3*pi)) == FiniteSet(0, pi) assert normalize_theta_set(FiniteSet(0, pi/2, pi, 2*pi)) == FiniteSet(0, pi/2, pi) assert normalize_theta_set(FiniteSet(0, -pi/2, -pi, -2*pi)) == FiniteSet(0, pi, pi*Rational(3, 2)) assert normalize_theta_set(FiniteSet(pi*Rational(-3, 2), pi/2)) == \ FiniteSet(pi/2) assert normalize_theta_set(FiniteSet(2*pi)) == FiniteSet(0) # Unions assert normalize_theta_set(Union(Interval(0, pi/3), Interval(pi/2, pi))) == \ Union(Interval(0, pi/3), Interval(pi/2, pi)) assert normalize_theta_set(Union(Interval(0, pi), Interval(2*pi, pi*Rational(7, 3)))) == \ Interval(0, pi) # ValueError for non-real sets raises(ValueError, lambda: normalize_theta_set(S.Complexes)) # NotImplementedError for subset of reals raises(NotImplementedError, lambda: normalize_theta_set(Interval(0, 1))) # NotImplementedError without pi as coefficient raises(NotImplementedError, lambda: normalize_theta_set(Interval(1, 2*pi))) raises(NotImplementedError, lambda: normalize_theta_set(Interval(2*pi, 10))) raises(NotImplementedError, lambda: normalize_theta_set(FiniteSet(0, 3, 3*pi))) def test_ComplexRegion_FiniteSet(): x, y, z, a, b, c = symbols('x y z a b c') # Issue #9669 assert ComplexRegion(FiniteSet(a, b, c)*FiniteSet(x, y, z)) == \ FiniteSet(a + I*x, a + I*y, a + I*z, b + I*x, b + I*y, b + I*z, c + I*x, c + I*y, c + I*z) assert ComplexRegion(FiniteSet(2)*FiniteSet(3)) == FiniteSet(2 + 3*I) def test_union_RealSubSet(): assert (S.Complexes).union(Interval(1, 2)) == S.Complexes assert (S.Complexes).union(S.Integers) == S.Complexes def test_issue_9980(): c1 = ComplexRegion(Interval(1, 2)*Interval(2, 3)) c2 = ComplexRegion(Interval(1, 5)*Interval(1, 3)) R = Union(c1, c2) assert simplify(R) == ComplexRegion(Union(Interval(1, 2)*Interval(2, 3), \ Interval(1, 5)*Interval(1, 3)), False) assert c1.func(*c1.args) == c1 assert R.func(*R.args) == R def test_issue_11732(): interval12 = Interval(1, 2) finiteset1234 = FiniteSet(1, 2, 3, 4) pointComplex = Tuple(1, 5) assert (interval12 in S.Naturals) == False assert (interval12 in S.Naturals0) == False assert (interval12 in S.Integers) == False assert (interval12 in S.Complexes) == False assert (finiteset1234 in S.Naturals) == False assert (finiteset1234 in S.Naturals0) == False assert (finiteset1234 in S.Integers) == False assert (finiteset1234 in S.Complexes) == False assert (pointComplex in S.Naturals) == False assert (pointComplex in S.Naturals0) == False assert (pointComplex in S.Integers) == False assert (pointComplex in S.Complexes) == True def test_issue_11730(): unit = Interval(0, 1) square = ComplexRegion(unit ** 2) assert Union(S.Complexes, FiniteSet(oo)) != S.Complexes assert Union(S.Complexes, FiniteSet(eye(4))) != S.Complexes assert Union(unit, square) == square assert Intersection(S.Reals, square) == unit def test_issue_11938(): unit = Interval(0, 1) ival = Interval(1, 2) cr1 = ComplexRegion(ival * unit) assert Intersection(cr1, S.Reals) == ival assert Intersection(cr1, unit) == FiniteSet(1) arg1 = Interval(0, S.Pi) arg2 = FiniteSet(S.Pi) arg3 = Interval(S.Pi / 4, 3 * S.Pi / 4) cp1 = ComplexRegion(unit * arg1, polar=True) cp2 = ComplexRegion(unit * arg2, polar=True) cp3 = ComplexRegion(unit * arg3, polar=True) assert Intersection(cp1, S.Reals) == Interval(-1, 1) assert Intersection(cp2, S.Reals) == Interval(-1, 0) assert Intersection(cp3, S.Reals) == FiniteSet(0) def test_issue_11914(): a, b = Interval(0, 1), Interval(0, pi) c, d = Interval(2, 3), Interval(pi, 3 * pi / 2) cp1 = ComplexRegion(a * b, polar=True) cp2 = ComplexRegion(c * d, polar=True) assert -3 in cp1.union(cp2) assert -3 in cp2.union(cp1) assert -5 not in cp1.union(cp2) def test_issue_9543(): assert ImageSet(Lambda(x, x**2), S.Naturals).is_subset(S.Reals) def test_issue_16871(): assert ImageSet(Lambda(x, x), FiniteSet(1)) == {1} assert ImageSet(Lambda(x, x - 3), S.Integers ).intersection(S.Integers) is S.Integers @XFAIL def test_issue_16871b(): assert ImageSet(Lambda(x, x - 3), S.Integers).is_subset(S.Integers) def test_issue_18050(): assert imageset(Lambda(x, I*x + 1), S.Integers ) == ImageSet(Lambda(x, I*x + 1), S.Integers) assert imageset(Lambda(x, 3*I*x + 4 + 8*I), S.Integers ) == ImageSet(Lambda(x, 3*I*x + 4 + 2*I), S.Integers) # no 'Mod' for next 2 tests: assert imageset(Lambda(x, 2*x + 3*I), S.Integers ) == ImageSet(Lambda(x, 2*x + 3*I), S.Integers) r = Symbol('r', positive=True) assert imageset(Lambda(x, r*x + 10), S.Integers ) == ImageSet(Lambda(x, r*x + 10), S.Integers) # reduce real part: assert imageset(Lambda(x, 3*x + 8 + 5*I), S.Integers ) == ImageSet(Lambda(x, 3*x + 2 + 5*I), S.Integers) def test_Rationals(): assert S.Integers.is_subset(S.Rationals) assert S.Naturals.is_subset(S.Rationals) assert S.Naturals0.is_subset(S.Rationals) assert S.Rationals.is_subset(S.Reals) assert S.Rationals.inf is -oo assert S.Rationals.sup is oo it = iter(S.Rationals) assert [next(it) for i in range(12)] == [ 0, 1, -1, S.Half, 2, Rational(-1, 2), -2, Rational(1, 3), 3, Rational(-1, 3), -3, Rational(2, 3)] assert Basic() not in S.Rationals assert S.Half in S.Rationals assert S.Rationals.contains(0.5) == Contains(0.5, S.Rationals, evaluate=False) assert 2 in S.Rationals r = symbols('r', rational=True) assert r in S.Rationals raises(TypeError, lambda: x in S.Rationals) # issue #18134: assert S.Rationals.boundary == S.Reals assert S.Rationals.closure == S.Reals assert S.Rationals.is_open == False assert S.Rationals.is_closed == False def test_NZQRC_unions(): # check that all trivial number set unions are simplified: nbrsets = (S.Naturals, S.Naturals0, S.Integers, S.Rationals, S.Reals, S.Complexes) unions = (Union(a, b) for a in nbrsets for b in nbrsets) assert all(u.is_Union is False for u in unions) def test_imageset_intersection(): n = Dummy() s = ImageSet(Lambda(n, -I*(I*(2*pi*n - pi/4) + log(Abs(sqrt(-I))))), S.Integers) assert s.intersect(S.Reals) == ImageSet( Lambda(n, 2*pi*n + pi*Rational(7, 4)), S.Integers) def test_issue_17858(): assert 1 in Range(-oo, oo) assert 0 in Range(oo, -oo, -1) assert oo not in Range(-oo, oo) assert -oo not in Range(-oo, oo) def test_issue_17859(): r = Range(-oo,oo) raises(ValueError,lambda: r[::2]) raises(ValueError, lambda: r[::-2]) r = Range(oo,-oo,-1) raises(ValueError,lambda: r[::2]) raises(ValueError, lambda: r[::-2])
54069084f9e1ac328c343a0fd5cd0f908b8e2a9331af1dbd6a790327bbf31e77
#!/usr/bin/env python """Distutils based setup script for SymPy. This uses Distutils (https://python.org/sigs/distutils-sig/) the standard python mechanism for installing packages. Optionally, you can use Setuptools (https://setuptools.readthedocs.io/en/latest/) to automatically handle dependencies. For the easiest installation just type the command (you'll probably need root privileges for that): python setup.py install This will install the library in the default location. For instructions on how to customize the install procedure read the output of: python setup.py --help install In addition, there are some other commands: python setup.py clean -> will clean all trash (*.pyc and stuff) python setup.py test -> will run the complete test suite python setup.py bench -> will run the complete benchmark suite python setup.py audit -> will run pyflakes checker on source code To get a full list of available commands, read the output of: python setup.py --help-commands Or, if all else fails, feel free to write to the sympy list at [email protected] and ask for help. """ import sys import os import shutil import glob import subprocess from distutils.command.sdist import sdist min_mpmath_version = '0.19' # This directory dir_setup = os.path.dirname(os.path.realpath(__file__)) extra_kwargs = {} try: from setuptools import setup, Command extra_kwargs['zip_safe'] = False extra_kwargs['entry_points'] = { 'console_scripts': [ 'isympy = isympy:main', ] } except ImportError: from distutils.core import setup, Command extra_kwargs['scripts'] = ['bin/isympy'] # handle mpmath deps in the hard way: from distutils.version import LooseVersion try: import mpmath if mpmath.__version__ < LooseVersion(min_mpmath_version): raise ImportError except ImportError: print("Please install the mpmath package with a version >= %s" % min_mpmath_version) sys.exit(-1) if sys.version_info < (3, 6): print("SymPy requires Python 3.6 or newer. Python %d.%d detected" % sys.version_info[:2]) sys.exit(-1) # Check that this list is uptodate against the result of the command: # python bin/generate_module_list.py modules = [ 'sympy.algebras', 'sympy.assumptions', 'sympy.assumptions.handlers', 'sympy.assumptions.predicates', 'sympy.assumptions.relation', 'sympy.benchmarks', 'sympy.calculus', 'sympy.categories', 'sympy.codegen', 'sympy.combinatorics', 'sympy.concrete', 'sympy.core', 'sympy.core.benchmarks', 'sympy.crypto', 'sympy.diffgeom', 'sympy.discrete', 'sympy.external', 'sympy.functions', 'sympy.functions.combinatorial', 'sympy.functions.elementary', 'sympy.functions.elementary.benchmarks', 'sympy.functions.special', 'sympy.functions.special.benchmarks', 'sympy.geometry', 'sympy.holonomic', 'sympy.integrals', 'sympy.integrals.benchmarks', 'sympy.integrals.rubi', 'sympy.integrals.rubi.parsetools', 'sympy.integrals.rubi.rubi_tests', 'sympy.integrals.rubi.rules', 'sympy.interactive', 'sympy.liealgebras', 'sympy.logic', 'sympy.logic.algorithms', 'sympy.logic.utilities', 'sympy.matrices', 'sympy.matrices.benchmarks', 'sympy.matrices.expressions', 'sympy.multipledispatch', 'sympy.ntheory', 'sympy.parsing', 'sympy.parsing.autolev', 'sympy.parsing.autolev._antlr', 'sympy.parsing.c', 'sympy.parsing.fortran', 'sympy.parsing.latex', 'sympy.parsing.latex._antlr', 'sympy.physics', 'sympy.physics.continuum_mechanics', 'sympy.physics.control', 'sympy.physics.hep', 'sympy.physics.mechanics', 'sympy.physics.optics', 'sympy.physics.quantum', 'sympy.physics.units', 'sympy.physics.units.definitions', 'sympy.physics.units.systems', 'sympy.physics.vector', 'sympy.plotting', 'sympy.plotting.intervalmath', 'sympy.plotting.pygletplot', 'sympy.polys', 'sympy.polys.agca', 'sympy.polys.benchmarks', 'sympy.polys.domains', 'sympy.polys.matrices', 'sympy.printing', 'sympy.printing.pretty', 'sympy.sandbox', 'sympy.series', 'sympy.series.benchmarks', 'sympy.sets', 'sympy.sets.handlers', 'sympy.simplify', 'sympy.solvers', 'sympy.solvers.benchmarks', 'sympy.solvers.diophantine', 'sympy.solvers.ode', 'sympy.stats', 'sympy.stats.sampling', 'sympy.strategies', 'sympy.strategies.branch', 'sympy.tensor', 'sympy.tensor.array', 'sympy.tensor.array.expressions', 'sympy.testing', 'sympy.unify', 'sympy.utilities', 'sympy.utilities._compilation', 'sympy.utilities.mathml', 'sympy.vector', ] class audit(Command): """Audits SymPy's source code for following issues: - Names which are used but not defined or used before they are defined. - Names which are redefined without having been used. """ description = "Audit SymPy source with PyFlakes" user_options = [] def initialize_options(self): self.all = None def finalize_options(self): pass def run(self): try: import pyflakes.scripts.pyflakes as flakes except ImportError: print("In order to run the audit, you need to have PyFlakes installed.") sys.exit(-1) dirs = (os.path.join(*d) for d in (m.split('.') for m in modules)) warns = 0 for dir in dirs: for filename in os.listdir(dir): if filename.endswith('.py') and filename != '__init__.py': warns += flakes.checkPath(os.path.join(dir, filename)) if warns > 0: print("Audit finished with total %d warnings" % warns) class clean(Command): """Cleans *.pyc and debian trashs, so you should get the same copy as is in the VCS. """ description = "remove build files" user_options = [("all", "a", "the same")] def initialize_options(self): self.all = None def finalize_options(self): pass def run(self): curr_dir = os.getcwd() for root, dirs, files in os.walk(dir_setup): for file in files: if file.endswith('.pyc') and os.path.isfile: os.remove(os.path.join(root, file)) os.chdir(dir_setup) names = ["python-build-stamp-2.4", "MANIFEST", "build", "dist", "doc/_build", "sample.tex"] for f in names: if os.path.isfile(f): os.remove(f) elif os.path.isdir(f): shutil.rmtree(f) for name in glob.glob(os.path.join(dir_setup, "doc", "src", "modules", "physics", "vector", "*.pdf")): if os.path.isfile(name): os.remove(name) os.chdir(curr_dir) class test_sympy(Command): """Runs all tests under the sympy/ folder """ description = "run all tests and doctests; also see bin/test and bin/doctest" user_options = [] # distutils complains if this is not here. def __init__(self, *args): self.args = args[0] # so we can pass it to other classes Command.__init__(self, *args) def initialize_options(self): # distutils wants this pass def finalize_options(self): # this too pass def run(self): from sympy.utilities import runtests runtests.run_all_tests() class run_benchmarks(Command): """Runs all SymPy benchmarks""" description = "run all benchmarks" user_options = [] # distutils complains if this is not here. def __init__(self, *args): self.args = args[0] # so we can pass it to other classes Command.__init__(self, *args) def initialize_options(self): # distutils wants this pass def finalize_options(self): # this too pass # we use py.test like architecture: # # o collector -- collects benchmarks # o runner -- executes benchmarks # o presenter -- displays benchmarks results # # this is done in sympy.utilities.benchmarking on top of py.test def run(self): from sympy.utilities import benchmarking benchmarking.main(['sympy']) class antlr(Command): """Generate code with antlr4""" description = "generate parser code from antlr grammars" user_options = [] # distutils complains if this is not here. def __init__(self, *args): self.args = args[0] # so we can pass it to other classes Command.__init__(self, *args) def initialize_options(self): # distutils wants this pass def finalize_options(self): # this too pass def run(self): from sympy.parsing.latex._build_latex_antlr import build_parser if not build_parser(): sys.exit(-1) class sdist_sympy(sdist): def run(self): # Fetch git commit hash and write down to commit_hash.txt before # shipped in tarball. commit_hash = None commit_hash_filepath = 'doc/commit_hash.txt' try: commit_hash = \ subprocess.check_output(['git', 'rev-parse', 'HEAD']) commit_hash = commit_hash.decode('ascii') commit_hash = commit_hash.rstrip() print('Commit hash found : {}.'.format(commit_hash)) print('Writing it to {}.'.format(commit_hash_filepath)) except: pass if commit_hash: with open(commit_hash_filepath, 'w') as f: f.write(commit_hash) super(sdist_sympy, self).run() try: os.remove(commit_hash_filepath) print( 'Successfully removed temporary file {}.' .format(commit_hash_filepath)) except OSError as e: print("Error deleting %s - %s." % (e.filename, e.strerror)) # Check that this list is uptodate against the result of the command: # python bin/generate_test_list.py tests = [ 'sympy.algebras.tests', 'sympy.assumptions.tests', 'sympy.calculus.tests', 'sympy.categories.tests', 'sympy.codegen.tests', 'sympy.combinatorics.tests', 'sympy.concrete.tests', 'sympy.core.tests', 'sympy.crypto.tests', 'sympy.diffgeom.tests', 'sympy.discrete.tests', 'sympy.external.tests', 'sympy.functions.combinatorial.tests', 'sympy.functions.elementary.tests', 'sympy.functions.special.tests', 'sympy.geometry.tests', 'sympy.holonomic.tests', 'sympy.integrals.rubi.parsetools.tests', 'sympy.integrals.rubi.rubi_tests.tests', 'sympy.integrals.rubi.tests', 'sympy.integrals.tests', 'sympy.interactive.tests', 'sympy.liealgebras.tests', 'sympy.logic.tests', 'sympy.matrices.expressions.tests', 'sympy.matrices.tests', 'sympy.multipledispatch.tests', 'sympy.ntheory.tests', 'sympy.parsing.tests', 'sympy.physics.continuum_mechanics.tests', 'sympy.physics.control.tests', 'sympy.physics.hep.tests', 'sympy.physics.mechanics.tests', 'sympy.physics.optics.tests', 'sympy.physics.quantum.tests', 'sympy.physics.tests', 'sympy.physics.units.tests', 'sympy.physics.vector.tests', 'sympy.plotting.intervalmath.tests', 'sympy.plotting.pygletplot.tests', 'sympy.plotting.tests', 'sympy.polys.agca.tests', 'sympy.polys.domains.tests', 'sympy.polys.matrices.tests', 'sympy.polys.tests', 'sympy.printing.pretty.tests', 'sympy.printing.tests', 'sympy.sandbox.tests', 'sympy.series.tests', 'sympy.sets.tests', 'sympy.simplify.tests', 'sympy.solvers.diophantine.tests', 'sympy.solvers.ode.tests', 'sympy.solvers.tests', 'sympy.stats.sampling.tests', 'sympy.stats.tests', 'sympy.strategies.branch.tests', 'sympy.strategies.tests', 'sympy.tensor.array.expressions.tests', 'sympy.tensor.array.tests', 'sympy.tensor.tests', 'sympy.testing.tests', 'sympy.unify.tests', 'sympy.utilities._compilation.tests', 'sympy.utilities.tests', 'sympy.vector.tests', ] with open(os.path.join(dir_setup, 'sympy', 'release.py')) as f: # Defines __version__ exec(f.read()) if __name__ == '__main__': setup(name='sympy', version=__version__, description='Computer algebra system (CAS) in Python', author='SymPy development team', author_email='[email protected]', license='BSD', keywords="Math CAS", url='https://sympy.org', py_modules=['isympy'], packages=['sympy'] + modules + tests, ext_modules=[], package_data={ 'sympy.utilities.mathml': ['data/*.xsl'], 'sympy.logic.benchmarks': ['input/*.cnf'], 'sympy.parsing.autolev': [ '*.g4', 'test-examples/*.al', 'test-examples/*.py', 'test-examples/pydy-example-repo/*.al', 'test-examples/pydy-example-repo/*.py', 'test-examples/README.txt', ], 'sympy.parsing.latex': ['*.txt', '*.g4'], 'sympy.integrals.rubi.parsetools': ['header.py.txt'], 'sympy.plotting.tests': ['test_region_*.png'], }, data_files=[('share/man/man1', ['doc/man/isympy.1'])], cmdclass={'test': test_sympy, 'bench': run_benchmarks, 'clean': clean, 'audit': audit, 'antlr': antlr, 'sdist': sdist_sympy, }, python_requires='>=3.6', classifiers=[ 'License :: OSI Approved :: BSD License', 'Operating System :: OS Independent', 'Programming Language :: Python', 'Topic :: Scientific/Engineering', 'Topic :: Scientific/Engineering :: Mathematics', 'Topic :: Scientific/Engineering :: Physics', 'Programming Language :: Python :: 3', 'Programming Language :: Python :: 3.6', 'Programming Language :: Python :: 3.7', 'Programming Language :: Python :: 3.8', 'Programming Language :: Python :: 3 :: Only', 'Programming Language :: Python :: Implementation :: CPython', 'Programming Language :: Python :: Implementation :: PyPy', ], install_requires=[ 'mpmath>=%s' % min_mpmath_version, ], **extra_kwargs )
4108c624627a960e67a3aef36397c58e905529c9c2ceb4d0fd8f3e3d12a29932
#!/usr/bin/env python import os import json from subprocess import check_output from collections import OrderedDict, defaultdict from collections.abc import Mapping import glob from contextlib import contextmanager import requests from requests_oauthlib import OAuth2 def main(version, push=None): """ WARNING: If push is given as --push then this will push the release to github. """ push = push == '--push' _GitHub_release(version, push) def error(msg): raise ValueError(msg) def blue(text): return "\033[34m%s\033[0m" % text def red(text): return "\033[31m%s\033[0m" % text def green(text): return "\033[32m%s\033[0m" % text def _GitHub_release(version, push, username=None, user='sympy', token=None, token_file_path="~/.sympy/release-token", repo='sympy', draft=False): """ Upload the release files to GitHub. The tag must be pushed up first. You can test on another repo by changing user and repo. """ if not requests: error("requests and requests-oauthlib must be installed to upload to GitHub") release_text = GitHub_release_text(version) short_version = get_sympy_short_version(version) tag = 'sympy-' + version prerelease = short_version != version urls = URLs(user=user, repo=repo) if not username: username = input("GitHub username: ") token = load_token_file(token_file_path) if not token: username, password, token = GitHub_authenticate(urls, username, token) # If the tag in question is not pushed up yet, then GitHub will just # create it off of master automatically, which is not what we want. We # could make it create it off the release branch, but even then, we would # not be sure that the correct commit is tagged. So we require that the # tag exist first. if not check_tag_exists(version): sys.exit(red("The tag for this version has not been pushed yet. Cannot upload the release.")) # See https://developer.github.com/v3/repos/releases/#create-a-release # First, create the release post = {} post['tag_name'] = tag post['name'] = "SymPy " + version post['body'] = release_text post['draft'] = draft post['prerelease'] = prerelease print("Creating release for tag", tag, end=' ') if push: result = query_GitHub(urls.releases_url, username, password=None, token=token, data=json.dumps(post)).json() release_id = result['id'] else: print(green("Not pushing!")) print(green("Done")) # Then, upload all the files to it. for key in descriptions: tarball = get_tarball_name(key, version) params = {} params['name'] = tarball if tarball.endswith('gz'): headers = {'Content-Type':'application/gzip'} elif tarball.endswith('pdf'): headers = {'Content-Type':'application/pdf'} elif tarball.endswith('zip'): headers = {'Content-Type':'application/zip'} else: headers = {'Content-Type':'application/octet-stream'} print("Uploading", tarball, end=' ') sys.stdout.flush() with open(os.path.join('release/release-' + version, tarball), 'rb') as f: if push: result = query_GitHub(urls.release_uploads_url % release_id, username, password=None, token=token, data=f, params=params, headers=headers).json() else: print(green("Not uploading!")) print(green("Done")) # TODO: download the files and check that they have the right sha256 sum def GitHub_release_text(version): """ Generate text to put in the GitHub release Markdown box """ shortversion = get_sympy_short_version(version) htmltable = table(version) out = """\ See https://github.com/sympy/sympy/wiki/release-notes-for-{shortversion} for the release notes. {htmltable} **Note**: Do not download the **Source code (zip)** or the **Source code (tar.gz)** files below. """ out = out.format(shortversion=shortversion, htmltable=htmltable) print(blue("Here are the release notes to copy into the GitHub release " "Markdown form:")) print() print(out) return out def get_sympy_short_version(version): """ Get the short version of SymPy being released, not including any rc tags (like 0.7.3) """ parts = version.split('.') # Remove rc tags # Handle both 1.0.rc1 and 1.1rc1 if not parts[-1].isdigit(): if parts[-1][0].isdigit(): parts[-1] = parts[-1][0] else: parts.pop(-1) return '.'.join(parts) class URLs(object): """ This class contains URLs and templates which used in requests to GitHub API """ def __init__(self, user="sympy", repo="sympy", api_url="https://api.github.com", authorize_url="https://api.github.com/authorizations", uploads_url='https://uploads.github.com', main_url='https://github.com'): """Generates all URLs and templates""" self.user = user self.repo = repo self.api_url = api_url self.authorize_url = authorize_url self.uploads_url = uploads_url self.main_url = main_url self.pull_list_url = api_url + "/repos" + "/" + user + "/" + repo + "/pulls" self.issue_list_url = api_url + "/repos/" + user + "/" + repo + "/issues" self.releases_url = api_url + "/repos/" + user + "/" + repo + "/releases" self.single_issue_template = self.issue_list_url + "/%d" self.single_pull_template = self.pull_list_url + "/%d" self.user_info_template = api_url + "/users/%s" self.user_repos_template = api_url + "/users/%s/repos" self.issue_comment_template = (api_url + "/repos" + "/" + user + "/" + repo + "/issues/%d" + "/comments") self.release_uploads_url = (uploads_url + "/repos/" + user + "/" + repo + "/releases/%d" + "/assets") self.release_download_url = (main_url + "/" + user + "/" + repo + "/releases/download/%s/%s") def load_token_file(path="~/.sympy/release-token"): print("> Using token file %s" % path) path = os.path.expanduser(path) path = os.path.abspath(path) if os.path.isfile(path): try: with open(path) as f: token = f.readline() except IOError: print("> Unable to read token file") return else: print("> Token file does not exist") return return token.strip() def GitHub_authenticate(urls, username, token=None): _login_message = """\ Enter your GitHub username & password or press ^C to quit. The password will be kept as a Python variable as long as this script is running and https to authenticate with GitHub, otherwise not saved anywhere else:\ """ if username: print("> Authenticating as %s" % username) else: print(_login_message) username = input("Username: ") authenticated = False if token: print("> Authenticating using token") try: GitHub_check_authentication(urls, username, None, token) except AuthenticationFailed: print("> Authentication failed") else: print("> OK") password = None authenticated = True while not authenticated: password = getpass("Password: ") try: print("> Checking username and password ...") GitHub_check_authentication(urls, username, password, None) except AuthenticationFailed: print("> Authentication failed") else: print("> OK.") authenticated = True if password: generate = input("> Generate API token? [Y/n] ") if generate.lower() in ["y", "ye", "yes", ""]: name = input("> Name of token on GitHub? [SymPy Release] ") if name == "": name = "SymPy Release" token = generate_token(urls, username, password, name=name) print("Your token is", token) print("Use this token from now on as GitHub_release:token=" + token + ",username=" + username) print(red("DO NOT share this token with anyone")) save = input("Do you want to save this token to a file [yes]? ") if save.lower().strip() in ['y', 'yes', 'ye', '']: save_token_file(token) return username, password, token def run(*cmdline, cwd=None): """ Run command in subprocess and get lines of output """ return check_output(cmdline, encoding='utf-8', cwd=cwd).splitlines() def check_tag_exists(version): """ Check if the tag for this release has been uploaded yet. """ tag = 'sympy-' + version all_tag_lines = run('git', 'ls-remote', '--tags', 'origin') return any(tag in tag_line for tag_line in all_tag_lines) def generate_token(urls, username, password, OTP=None, name="SymPy Release"): enc_data = json.dumps( { "scopes": ["public_repo"], "note": name } ) url = urls.authorize_url rep = query_GitHub(url, username=username, password=password, data=enc_data).json() return rep["token"] def GitHub_check_authentication(urls, username, password, token): """ Checks that username & password is valid. """ query_GitHub(urls.api_url, username, password, token) class AuthenticationFailed(Exception): pass def query_GitHub(url, username=None, password=None, token=None, data=None, OTP=None, headers=None, params=None, files=None): """ Query GitHub API. In case of a multipage result, DOES NOT query the next page. """ headers = headers or {} if OTP: headers['X-GitHub-OTP'] = OTP if token: auth = OAuth2(client_id=username, token=dict(access_token=token, token_type='bearer')) else: auth = HTTPBasicAuth(username, password) if data: r = requests.post(url, auth=auth, data=data, headers=headers, params=params, files=files) else: r = requests.get(url, auth=auth, headers=headers, params=params, stream=True) if r.status_code == 401: two_factor = r.headers.get('X-GitHub-OTP') if two_factor: print("A two-factor authentication code is required:", two_factor.split(';')[1].strip()) OTP = input("Authentication code: ") return query_GitHub(url, username=username, password=password, token=token, data=data, OTP=OTP) raise AuthenticationFailed("invalid username or password") r.raise_for_status() return r def save_token_file(token): token_file = input("> Enter token file location [~/.sympy/release-token] ") token_file = token_file or "~/.sympy/release-token" token_file_expand = os.path.expanduser(token_file) token_file_expand = os.path.abspath(token_file_expand) token_folder, _ = os.path.split(token_file_expand) try: if not os.path.isdir(token_folder): os.mkdir(token_folder, 0o700) with open(token_file_expand, 'w') as f: f.write(token + '\n') os.chmod(token_file_expand, stat.S_IREAD | stat.S_IWRITE) except OSError as e: print("> Unable to create folder for token file: ", e) return except IOError as e: print("> Unable to save token file: ", e) return return token_file def table(version): """ Make an html table of the downloads. This is for pasting into the GitHub releases page. See GitHub_release(). """ tarball_formatter_dict = dict(_tarball_format(version)) shortversion = get_sympy_short_version(version) tarball_formatter_dict['version'] = shortversion sha256s = [i.split('\t') for i in _sha256(version, print_=False, local=True).split('\n')] sha256s_dict = {name: sha256 for sha256, name in sha256s} sizes = [i.split('\t') for i in _size(version, print_=False).split('\n')] sizes_dict = {name: size for size, name in sizes} table = [] # https://docs.python.org/2/library/contextlib.html#contextlib.contextmanager. Not # recommended as a real way to generate html, but it works better than # anything else I've tried. @contextmanager def tag(name): table.append("<%s>" % name) yield table.append("</%s>" % name) @contextmanager def a_href(link): table.append("<a href=\"%s\">" % link) yield table.append("</a>") with tag('table'): with tag('tr'): for headname in ["Filename", "Description", "size", "sha256"]: with tag("th"): table.append(headname) for key in descriptions: name = get_tarball_name(key, version) with tag('tr'): with tag('td'): with a_href('https://github.com/sympy/sympy/releases/download/sympy-%s/%s' % (version, name)): with tag('b'): table.append(name) with tag('td'): table.append(descriptions[key].format(**tarball_formatter_dict)) with tag('td'): table.append(sizes_dict[name]) with tag('td'): table.append(sha256s_dict[name]) out = ' '.join(table) return out descriptions = OrderedDict([ ('source', "The SymPy source installer.",), ('wheel', "A wheel of the package.",), ('html', '''Html documentation. This is the same as the <a href="https://docs.sympy.org/latest/index.html">online documentation</a>.''',), ('pdf', '''Pdf version of the <a href="https://docs.sympy.org/latest/index.html"> html documentation</a>.''',), ]) def _size(version, print_=True): """ Print the sizes of the release files. Run locally. """ out = run(*(['du', '-h'] + release_files(version))) out = [i.split() for i in out] out = '\n'.join(["%s\t%s" % (i, os.path.split(j)[1]) for i, j in out]) if print_: print(out) return out def _sha256(version, print_=True, local=False): if local: out = run(*(['shasum', '-a', '256'] + release_files(version))) else: raise ValueError('Should not get here...') # out = run(*(['shasum', '-a', '256', '/root/release/*'])) # Remove the release/ part for printing. Useful for copy-pasting into the # release notes. out = [i.split() for i in out] out = '\n'.join(["%s\t%s" % (i, os.path.split(j)[1]) for i, j in out]) if print_: print(out) return out def get_tarball_name(file, version): """ Get the name of a tarball file should be one of source-orig: The original name of the source tarball source-orig-notar: The name of the untarred directory source: The source tarball (after renaming) wheel: The wheel html: The name of the html zip html-nozip: The name of the html, without ".zip" pdf-orig: The original name of the pdf file pdf: The name of the pdf file (after renaming) """ doctypename = defaultdict(str, {'html': 'zip', 'pdf': 'pdf'}) if file in {'source-orig', 'source'}: name = 'sympy-{version}.tar.gz' elif file == 'source-orig-notar': name = "sympy-{version}" elif file in {'html', 'pdf', 'html-nozip'}: name = "sympy-docs-{type}-{version}" if file == 'html-nozip': # zip files keep the name of the original zipped directory. See # https://github.com/sympy/sympy/issues/7087. file = 'html' else: name += ".{extension}" elif file == 'pdf-orig': name = "sympy-{version}.pdf" elif file == 'wheel': name = 'sympy-{version}-py3-none-any.whl' else: raise ValueError(file + " is not a recognized argument") ret = name.format(version=version, type=file, extension=doctypename[file]) return ret def release_files(version): """ Returns the list of local release files """ paths = glob.glob('release/release-' + version + '/*') if not paths: raise ValueError("No release files found") return paths tarball_name_types = { 'source-orig', 'source-orig-notar', 'source', 'wheel', 'html', 'html-nozip', 'pdf-orig', 'pdf', } # Have to make this lazy so that version can be defined. class _tarball_format(Mapping): def __init__(self, version): self.version = version def __getitem__(self, name): return get_tarball_name(name, self.version) def __iter__(self): return iter(tarball_name_types) def __len__(self): return len(tarball_name_types) if __name__ == "__main__": import sys main(*sys.argv[1:])
5b46c2e75f53e6f7e895a82c60c2856eb5e89010e5ad1e560a56f2d0e6cda151
""" SymPy is a Python library for symbolic mathematics. It aims to become a full-featured computer algebra system (CAS) while keeping the code as simple as possible in order to be comprehensible and easily extensible. SymPy is written entirely in Python. It depends on mpmath, and other external libraries may be optionally for things like plotting support. See the webpage for more information and documentation: https://sympy.org """ import sys if sys.version_info < (3, 6): raise ImportError("Python version 3.6 or above is required for SymPy.") del sys try: import mpmath except ImportError: raise ImportError("SymPy now depends on mpmath as an external library. " "See https://docs.sympy.org/latest/install.html#mpmath for more information.") del mpmath from sympy.release import __version__ if 'dev' in __version__: def enable_warnings(): import warnings warnings.filterwarnings('default', '.*', DeprecationWarning, module='sympy.*') del warnings enable_warnings() del enable_warnings def __sympy_debug(): # helper function so we don't import os globally import os debug_str = os.getenv('SYMPY_DEBUG', 'False') if debug_str in ('True', 'False'): return eval(debug_str) else: raise RuntimeError("unrecognized value for SYMPY_DEBUG: %s" % debug_str) SYMPY_DEBUG = __sympy_debug() # type: bool from .core import (sympify, SympifyError, cacheit, Basic, Atom, preorder_traversal, S, Expr, AtomicExpr, UnevaluatedExpr, Symbol, Wild, Dummy, symbols, var, Number, Float, Rational, Integer, NumberSymbol, RealNumber, igcd, ilcm, seterr, E, I, nan, oo, pi, zoo, AlgebraicNumber, comp, mod_inverse, Pow, integer_nthroot, integer_log, Mul, prod, Add, Mod, Rel, Eq, Ne, Lt, Le, Gt, Ge, Equality, GreaterThan, LessThan, Unequality, StrictGreaterThan, StrictLessThan, vectorize, Lambda, WildFunction, Derivative, diff, FunctionClass, Function, Subs, expand, PoleError, count_ops, expand_mul, expand_log, expand_func, expand_trig, expand_complex, expand_multinomial, nfloat, expand_power_base, expand_power_exp, arity, PrecisionExhausted, N, evalf, Tuple, Dict, gcd_terms, factor_terms, factor_nc, evaluate, Catalan, EulerGamma, GoldenRatio, TribonacciConstant) from .logic import (to_cnf, to_dnf, to_nnf, And, Or, Not, Xor, Nand, Nor, Implies, Equivalent, ITE, POSform, SOPform, simplify_logic, bool_map, true, false, satisfiable) from .assumptions import (AppliedPredicate, Predicate, AssumptionsContext, assuming, Q, ask, register_handler, remove_handler, refine) from .polys import (Poly, PurePoly, poly_from_expr, parallel_poly_from_expr, degree, total_degree, degree_list, LC, LM, LT, pdiv, prem, pquo, pexquo, div, rem, quo, exquo, half_gcdex, gcdex, invert, subresultants, resultant, discriminant, cofactors, gcd_list, gcd, lcm_list, lcm, terms_gcd, trunc, monic, content, primitive, compose, decompose, sturm, gff_list, gff, sqf_norm, sqf_part, sqf_list, sqf, factor_list, factor, intervals, refine_root, count_roots, real_roots, nroots, ground_roots, nth_power_roots_poly, cancel, reduced, groebner, is_zero_dimensional, GroebnerBasis, poly, symmetrize, horner, interpolate, rational_interpolate, viete, together, BasePolynomialError, ExactQuotientFailed, PolynomialDivisionFailed, OperationNotSupported, HeuristicGCDFailed, HomomorphismFailed, IsomorphismFailed, ExtraneousFactors, EvaluationFailed, RefinementFailed, CoercionFailed, NotInvertible, NotReversible, NotAlgebraic, DomainError, PolynomialError, UnificationFailed, GeneratorsError, GeneratorsNeeded, ComputationFailed, UnivariatePolynomialError, MultivariatePolynomialError, PolificationFailed, OptionError, FlagError, minpoly, minimal_polynomial, primitive_element, field_isomorphism, to_number_field, isolate, itermonomials, Monomial, lex, grlex, grevlex, ilex, igrlex, igrevlex, CRootOf, rootof, RootOf, ComplexRootOf, RootSum, roots, Domain, FiniteField, IntegerRing, RationalField, RealField, ComplexField, PythonFiniteField, GMPYFiniteField, PythonIntegerRing, GMPYIntegerRing, PythonRational, GMPYRationalField, AlgebraicField, PolynomialRing, FractionField, ExpressionDomain, FF_python, FF_gmpy, ZZ_python, ZZ_gmpy, QQ_python, QQ_gmpy, GF, FF, ZZ, QQ, ZZ_I, QQ_I, RR, CC, EX, EXRAW, construct_domain, swinnerton_dyer_poly, cyclotomic_poly, symmetric_poly, random_poly, interpolating_poly, jacobi_poly, chebyshevt_poly, chebyshevu_poly, hermite_poly, legendre_poly, laguerre_poly, apart, apart_list, assemble_partfrac_list, Options, ring, xring, vring, sring, field, xfield, vfield, sfield) from .series import (Order, O, limit, Limit, gruntz, series, approximants, residue, EmptySequence, SeqPer, SeqFormula, sequence, SeqAdd, SeqMul, fourier_series, fps, difference_delta, limit_seq) from .functions import (factorial, factorial2, rf, ff, binomial, RisingFactorial, FallingFactorial, subfactorial, carmichael, fibonacci, lucas, motzkin, tribonacci, harmonic, bernoulli, bell, euler, catalan, genocchi, partition, sqrt, root, Min, Max, Id, real_root, cbrt, re, im, sign, Abs, conjugate, arg, polar_lift, periodic_argument, unbranched_argument, principal_branch, transpose, adjoint, polarify, unpolarify, sin, cos, tan, sec, csc, cot, sinc, asin, acos, atan, asec, acsc, acot, atan2, exp_polar, exp, ln, log, LambertW, sinh, cosh, tanh, coth, sech, csch, asinh, acosh, atanh, acoth, asech, acsch, floor, ceiling, frac, Piecewise, piecewise_fold, erf, erfc, erfi, erf2, erfinv, erfcinv, erf2inv, Ei, expint, E1, li, Li, Si, Ci, Shi, Chi, fresnels, fresnelc, gamma, lowergamma, uppergamma, polygamma, loggamma, digamma, trigamma, multigamma, dirichlet_eta, zeta, lerchphi, polylog, stieltjes, Eijk, LeviCivita, KroneckerDelta, SingularityFunction, DiracDelta, Heaviside, bspline_basis, bspline_basis_set, interpolating_spline, besselj, bessely, besseli, besselk, hankel1, hankel2, jn, yn, jn_zeros, hn1, hn2, airyai, airybi, airyaiprime, airybiprime, marcumq, hyper, meijerg, appellf1, legendre, assoc_legendre, hermite, chebyshevt, chebyshevu, chebyshevu_root, chebyshevt_root, laguerre, assoc_laguerre, gegenbauer, jacobi, jacobi_normalized, Ynm, Ynm_c, Znm, elliptic_k, elliptic_f, elliptic_e, elliptic_pi, beta, mathieus, mathieuc, mathieusprime, mathieucprime, riemann_xi, betainc, betainc_regularized) from .ntheory import (nextprime, prevprime, prime, primepi, primerange, randprime, Sieve, sieve, primorial, cycle_length, composite, compositepi, isprime, divisors, proper_divisors, factorint, multiplicity, perfect_power, pollard_pm1, pollard_rho, primefactors, totient, trailing, divisor_count, proper_divisor_count, divisor_sigma, factorrat, reduced_totient, primenu, primeomega, mersenne_prime_exponent, is_perfect, is_mersenne_prime, is_abundant, is_deficient, is_amicable, abundance, npartitions, is_primitive_root, is_quad_residue, legendre_symbol, jacobi_symbol, n_order, sqrt_mod, quadratic_residues, primitive_root, nthroot_mod, is_nthpow_residue, sqrt_mod_iter, mobius, discrete_log, quadratic_congruence, binomial_coefficients, binomial_coefficients_list, multinomial_coefficients, continued_fraction_periodic, continued_fraction_iterator, continued_fraction_reduce, continued_fraction_convergents, continued_fraction, egyptian_fraction) from .concrete import product, Product, summation, Sum from .discrete import (fft, ifft, ntt, intt, fwht, ifwht, mobius_transform, inverse_mobius_transform, convolution, covering_product, intersecting_product) from .simplify import (simplify, hypersimp, hypersimilar, logcombine, separatevars, posify, besselsimp, kroneckersimp, signsimp, bottom_up, nsimplify, FU, fu, sqrtdenest, cse, use, epath, EPath, hyperexpand, collect, rcollect, radsimp, collect_const, fraction, numer, denom, trigsimp, exptrigsimp, powsimp, powdenest, combsimp, gammasimp, ratsimp, ratsimpmodprime) from .sets import (Set, Interval, Union, EmptySet, FiniteSet, ProductSet, Intersection, DisjointUnion, imageset, Complement, SymmetricDifference, ImageSet, Range, ComplexRegion, Reals, Contains, ConditionSet, Ordinal, OmegaPower, ord0, PowerSet, Naturals, Naturals0, UniversalSet, Integers, Rationals) from .solvers import (solve, solve_linear_system, solve_linear_system_LU, solve_undetermined_coeffs, nsolve, solve_linear, checksol, det_quick, inv_quick, check_assumptions, failing_assumptions, diophantine, rsolve, rsolve_poly, rsolve_ratio, rsolve_hyper, checkodesol, classify_ode, dsolve, homogeneous_order, solve_poly_system, solve_triangulated, pde_separate, pde_separate_add, pde_separate_mul, pdsolve, classify_pde, checkpdesol, ode_order, reduce_inequalities, reduce_abs_inequality, reduce_abs_inequalities, solve_poly_inequality, solve_rational_inequalities, solve_univariate_inequality, decompogen, solveset, linsolve, linear_eq_to_matrix, nonlinsolve, substitution, Complexes) from .matrices import (ShapeError, NonSquareMatrixError, GramSchmidt, casoratian, diag, eye, hessian, jordan_cell, list2numpy, matrix2numpy, matrix_multiply_elementwise, ones, randMatrix, rot_axis1, rot_axis2, rot_axis3, symarray, wronskian, zeros, MutableDenseMatrix, DeferredVector, MatrixBase, Matrix, MutableMatrix, MutableSparseMatrix, banded, ImmutableDenseMatrix, ImmutableSparseMatrix, ImmutableMatrix, SparseMatrix, MatrixSlice, BlockDiagMatrix, BlockMatrix, FunctionMatrix, Identity, Inverse, MatAdd, MatMul, MatPow, MatrixExpr, MatrixSymbol, Trace, Transpose, ZeroMatrix, OneMatrix, blockcut, block_collapse, matrix_symbols, Adjoint, hadamard_product, HadamardProduct, HadamardPower, Determinant, det, diagonalize_vector, DiagMatrix, DiagonalMatrix, DiagonalOf, trace, DotProduct, kronecker_product, KroneckerProduct, PermutationMatrix, MatrixPermute, Permanent, per) from .geometry import (Point, Point2D, Point3D, Line, Ray, Segment, Line2D, Segment2D, Ray2D, Line3D, Segment3D, Ray3D, Plane, Ellipse, Circle, Polygon, RegularPolygon, Triangle, rad, deg, are_similar, centroid, convex_hull, idiff, intersection, closest_points, farthest_points, GeometryError, Curve, Parabola) from .utilities import (flatten, group, take, subsets, variations, numbered_symbols, cartes, capture, dict_merge, postorder_traversal, interactive_traversal, prefixes, postfixes, sift, topological_sort, unflatten, has_dups, has_variety, reshape, default_sort_key, ordered, rotations, filldedent, lambdify, source, threaded, xthreaded, public, memoize_property, timed) from .integrals import (integrate, Integral, line_integrate, mellin_transform, inverse_mellin_transform, MellinTransform, InverseMellinTransform, laplace_transform, inverse_laplace_transform, LaplaceTransform, InverseLaplaceTransform, fourier_transform, inverse_fourier_transform, FourierTransform, InverseFourierTransform, sine_transform, inverse_sine_transform, SineTransform, InverseSineTransform, cosine_transform, inverse_cosine_transform, CosineTransform, InverseCosineTransform, hankel_transform, inverse_hankel_transform, HankelTransform, InverseHankelTransform, singularityintegrate) from .tensor import (IndexedBase, Idx, Indexed, get_contraction_structure, get_indices, shape, MutableDenseNDimArray, ImmutableDenseNDimArray, MutableSparseNDimArray, ImmutableSparseNDimArray, NDimArray, tensorproduct, tensorcontraction, tensordiagonal, derive_by_array, permutedims, Array, DenseNDimArray, SparseNDimArray) from .parsing import parse_expr from .calculus import (euler_equations, singularities, is_increasing, is_strictly_increasing, is_decreasing, is_strictly_decreasing, is_monotonic, finite_diff_weights, apply_finite_diff, as_finite_diff, differentiate_finite, periodicity, not_empty_in, AccumBounds, is_convex, stationary_points, minimum, maximum) from .algebras import Quaternion from .printing import (pager_print, pretty, pretty_print, pprint, pprint_use_unicode, pprint_try_use_unicode, latex, print_latex, multiline_latex, mathml, print_mathml, python, print_python, pycode, ccode, print_ccode, glsl_code, print_glsl, cxxcode, fcode, print_fcode, rcode, print_rcode, jscode, print_jscode, julia_code, mathematica_code, octave_code, rust_code, print_gtk, preview, srepr, print_tree, StrPrinter, sstr, sstrrepr, TableForm, dotprint, maple_code, print_maple_code) from .testing import test, doctest # This module causes conflicts with other modules: # from .stats import * # Adds about .04-.05 seconds of import time # from combinatorics import * # This module is slow to import: #from physics import units from .plotting import plot, textplot, plot_backends, plot_implicit, plot_parametric from .interactive import init_session, init_printing evalf._create_evalf_table() __all__ = [ # sympy.core 'sympify', 'SympifyError', 'cacheit', 'Basic', 'Atom', 'preorder_traversal', 'S', 'Expr', 'AtomicExpr', 'UnevaluatedExpr', 'Symbol', 'Wild', 'Dummy', 'symbols', 'var', 'Number', 'Float', 'Rational', 'Integer', 'NumberSymbol', 'RealNumber', 'igcd', 'ilcm', 'seterr', 'E', 'I', 'nan', 'oo', 'pi', 'zoo', 'AlgebraicNumber', 'comp', 'mod_inverse', 'Pow', 'integer_nthroot', 'integer_log', 'Mul', 'prod', 'Add', 'Mod', 'Rel', 'Eq', 'Ne', 'Lt', 'Le', 'Gt', 'Ge', 'Equality', 'GreaterThan', 'LessThan', 'Unequality', 'StrictGreaterThan', 'StrictLessThan', 'vectorize', 'Lambda', 'WildFunction', 'Derivative', 'diff', 'FunctionClass', 'Function', 'Subs', 'expand', 'PoleError', 'count_ops', 'expand_mul', 'expand_log', 'expand_func', 'expand_trig', 'expand_complex', 'expand_multinomial', 'nfloat', 'expand_power_base', 'expand_power_exp', 'arity', 'PrecisionExhausted', 'N', 'evalf', 'Tuple', 'Dict', 'gcd_terms', 'factor_terms', 'factor_nc', 'evaluate', 'Catalan', 'EulerGamma', 'GoldenRatio', 'TribonacciConstant', # sympy.logic 'to_cnf', 'to_dnf', 'to_nnf', 'And', 'Or', 'Not', 'Xor', 'Nand', 'Nor', 'Implies', 'Equivalent', 'ITE', 'POSform', 'SOPform', 'simplify_logic', 'bool_map', 'true', 'false', 'satisfiable', # sympy.assumptions 'AppliedPredicate', 'Predicate', 'AssumptionsContext', 'assuming', 'Q', 'ask', 'register_handler', 'remove_handler', 'refine', # sympy.polys 'Poly', 'PurePoly', 'poly_from_expr', 'parallel_poly_from_expr', 'degree', 'total_degree', 'degree_list', 'LC', 'LM', 'LT', 'pdiv', 'prem', 'pquo', 'pexquo', 'div', 'rem', 'quo', 'exquo', 'half_gcdex', 'gcdex', 'invert', 'subresultants', 'resultant', 'discriminant', 'cofactors', 'gcd_list', 'gcd', 'lcm_list', 'lcm', 'terms_gcd', 'trunc', 'monic', 'content', 'primitive', 'compose', 'decompose', 'sturm', 'gff_list', 'gff', 'sqf_norm', 'sqf_part', 'sqf_list', 'sqf', 'factor_list', 'factor', 'intervals', 'refine_root', 'count_roots', 'real_roots', 'nroots', 'ground_roots', 'nth_power_roots_poly', 'cancel', 'reduced', 'groebner', 'is_zero_dimensional', 'GroebnerBasis', 'poly', 'symmetrize', 'horner', 'interpolate', 'rational_interpolate', 'viete', 'together', 'BasePolynomialError', 'ExactQuotientFailed', 'PolynomialDivisionFailed', 'OperationNotSupported', 'HeuristicGCDFailed', 'HomomorphismFailed', 'IsomorphismFailed', 'ExtraneousFactors', 'EvaluationFailed', 'RefinementFailed', 'CoercionFailed', 'NotInvertible', 'NotReversible', 'NotAlgebraic', 'DomainError', 'PolynomialError', 'UnificationFailed', 'GeneratorsError', 'GeneratorsNeeded', 'ComputationFailed', 'UnivariatePolynomialError', 'MultivariatePolynomialError', 'PolificationFailed', 'OptionError', 'FlagError', 'minpoly', 'minimal_polynomial', 'primitive_element', 'field_isomorphism', 'to_number_field', 'isolate', 'itermonomials', 'Monomial', 'lex', 'grlex', 'grevlex', 'ilex', 'igrlex', 'igrevlex', 'CRootOf', 'rootof', 'RootOf', 'ComplexRootOf', 'RootSum', 'roots', 'Domain', 'FiniteField', 'IntegerRing', 'RationalField', 'RealField', 'ComplexField', 'PythonFiniteField', 'GMPYFiniteField', 'PythonIntegerRing', 'GMPYIntegerRing', 'PythonRational', 'GMPYRationalField', 'AlgebraicField', 'PolynomialRing', 'FractionField', 'ExpressionDomain', 'FF_python', 'FF_gmpy', 'ZZ_python', 'ZZ_gmpy', 'QQ_python', 'QQ_gmpy', 'GF', 'FF', 'ZZ', 'QQ', 'ZZ_I', 'QQ_I', 'RR', 'CC', 'EX', 'EXRAW', 'construct_domain', 'swinnerton_dyer_poly', 'cyclotomic_poly', 'symmetric_poly', 'random_poly', 'interpolating_poly', 'jacobi_poly', 'chebyshevt_poly', 'chebyshevu_poly', 'hermite_poly', 'legendre_poly', 'laguerre_poly', 'apart', 'apart_list', 'assemble_partfrac_list', 'Options', 'ring', 'xring', 'vring', 'sring', 'field', 'xfield', 'vfield', 'sfield', # sympy.series 'Order', 'O', 'limit', 'Limit', 'gruntz', 'series', 'approximants', 'residue', 'EmptySequence', 'SeqPer', 'SeqFormula', 'sequence', 'SeqAdd', 'SeqMul', 'fourier_series', 'fps', 'difference_delta', 'limit_seq', # sympy.functions 'factorial', 'factorial2', 'rf', 'ff', 'binomial', 'RisingFactorial', 'FallingFactorial', 'subfactorial', 'carmichael', 'fibonacci', 'lucas', 'motzkin', 'tribonacci', 'harmonic', 'bernoulli', 'bell', 'euler', 'catalan', 'genocchi', 'partition', 'sqrt', 'root', 'Min', 'Max', 'Id', 'real_root', 'cbrt', 're', 'im', 'sign', 'Abs', 'conjugate', 'arg', 'polar_lift', 'periodic_argument', 'unbranched_argument', 'principal_branch', 'transpose', 'adjoint', 'polarify', 'unpolarify', 'sin', 'cos', 'tan', 'sec', 'csc', 'cot', 'sinc', 'asin', 'acos', 'atan', 'asec', 'acsc', 'acot', 'atan2', 'exp_polar', 'exp', 'ln', 'log', 'LambertW', 'sinh', 'cosh', 'tanh', 'coth', 'sech', 'csch', 'asinh', 'acosh', 'atanh', 'acoth', 'asech', 'acsch', 'floor', 'ceiling', 'frac', 'Piecewise', 'piecewise_fold', 'erf', 'erfc', 'erfi', 'erf2', 'erfinv', 'erfcinv', 'erf2inv', 'Ei', 'expint', 'E1', 'li', 'Li', 'Si', 'Ci', 'Shi', 'Chi', 'fresnels', 'fresnelc', 'gamma', 'lowergamma', 'uppergamma', 'polygamma', 'loggamma', 'digamma', 'trigamma', 'multigamma', 'dirichlet_eta', 'zeta', 'lerchphi', 'polylog', 'stieltjes', 'Eijk', 'LeviCivita', 'KroneckerDelta', 'SingularityFunction', 'DiracDelta', 'Heaviside', 'bspline_basis', 'bspline_basis_set', 'interpolating_spline', 'besselj', 'bessely', 'besseli', 'besselk', 'hankel1', 'hankel2', 'jn', 'yn', 'jn_zeros', 'hn1', 'hn2', 'airyai', 'airybi', 'airyaiprime', 'airybiprime', 'marcumq', 'hyper', 'meijerg', 'appellf1', 'legendre', 'assoc_legendre', 'hermite', 'chebyshevt', 'chebyshevu', 'chebyshevu_root', 'chebyshevt_root', 'laguerre', 'assoc_laguerre', 'gegenbauer', 'jacobi', 'jacobi_normalized', 'Ynm', 'Ynm_c', 'Znm', 'elliptic_k', 'elliptic_f', 'elliptic_e', 'elliptic_pi', 'beta', 'mathieus', 'mathieuc', 'mathieusprime', 'mathieucprime', 'riemann_xi','betainc', 'betainc_regularized', # sympy.ntheory 'nextprime', 'prevprime', 'prime', 'primepi', 'primerange', 'randprime', 'Sieve', 'sieve', 'primorial', 'cycle_length', 'composite', 'compositepi', 'isprime', 'divisors', 'proper_divisors', 'factorint', 'multiplicity', 'perfect_power', 'pollard_pm1', 'pollard_rho', 'primefactors', 'totient', 'trailing', 'divisor_count', 'proper_divisor_count', 'divisor_sigma', 'factorrat', 'reduced_totient', 'primenu', 'primeomega', 'mersenne_prime_exponent', 'is_perfect', 'is_mersenne_prime', 'is_abundant', 'is_deficient', 'is_amicable', 'abundance', 'npartitions', 'is_primitive_root', 'is_quad_residue', 'legendre_symbol', 'jacobi_symbol', 'n_order', 'sqrt_mod', 'quadratic_residues', 'primitive_root', 'nthroot_mod', 'is_nthpow_residue', 'sqrt_mod_iter', 'mobius', 'discrete_log', 'quadratic_congruence', 'binomial_coefficients', 'binomial_coefficients_list', 'multinomial_coefficients', 'continued_fraction_periodic', 'continued_fraction_iterator', 'continued_fraction_reduce', 'continued_fraction_convergents', 'continued_fraction', 'egyptian_fraction', # sympy.concrete 'product', 'Product', 'summation', 'Sum', # sympy.discrete 'fft', 'ifft', 'ntt', 'intt', 'fwht', 'ifwht', 'mobius_transform', 'inverse_mobius_transform', 'convolution', 'covering_product', 'intersecting_product', # sympy.simplify 'simplify', 'hypersimp', 'hypersimilar', 'logcombine', 'separatevars', 'posify', 'besselsimp', 'kroneckersimp', 'signsimp', 'bottom_up', 'nsimplify', 'FU', 'fu', 'sqrtdenest', 'cse', 'use', 'epath', 'EPath', 'hyperexpand', 'collect', 'rcollect', 'radsimp', 'collect_const', 'fraction', 'numer', 'denom', 'trigsimp', 'exptrigsimp', 'powsimp', 'powdenest', 'combsimp', 'gammasimp', 'ratsimp', 'ratsimpmodprime', # sympy.sets 'Set', 'Interval', 'Union', 'EmptySet', 'FiniteSet', 'ProductSet', 'Intersection', 'imageset', 'DisjointUnion', 'Complement', 'SymmetricDifference', 'ImageSet', 'Range', 'ComplexRegion', 'Reals', 'Contains', 'ConditionSet', 'Ordinal', 'OmegaPower', 'ord0', 'PowerSet', 'Reals', 'Naturals', 'Naturals0', 'UniversalSet', 'Integers', 'Rationals', # sympy.solvers 'solve', 'solve_linear_system', 'solve_linear_system_LU', 'solve_undetermined_coeffs', 'nsolve', 'solve_linear', 'checksol', 'det_quick', 'inv_quick', 'check_assumptions', 'failing_assumptions', 'diophantine', 'rsolve', 'rsolve_poly', 'rsolve_ratio', 'rsolve_hyper', 'checkodesol', 'classify_ode', 'dsolve', 'homogeneous_order', 'solve_poly_system', 'solve_triangulated', 'pde_separate', 'pde_separate_add', 'pde_separate_mul', 'pdsolve', 'classify_pde', 'checkpdesol', 'ode_order', 'reduce_inequalities', 'reduce_abs_inequality', 'reduce_abs_inequalities', 'solve_poly_inequality', 'solve_rational_inequalities', 'solve_univariate_inequality', 'decompogen', 'solveset', 'linsolve', 'linear_eq_to_matrix', 'nonlinsolve', 'substitution', 'Complexes', # sympy.matrices 'ShapeError', 'NonSquareMatrixError', 'GramSchmidt', 'casoratian', 'diag', 'eye', 'hessian', 'jordan_cell', 'list2numpy', 'matrix2numpy', 'matrix_multiply_elementwise', 'ones', 'randMatrix', 'rot_axis1', 'rot_axis2', 'rot_axis3', 'symarray', 'wronskian', 'zeros', 'MutableDenseMatrix', 'DeferredVector', 'MatrixBase', 'Matrix', 'MutableMatrix', 'MutableSparseMatrix', 'banded', 'ImmutableDenseMatrix', 'ImmutableSparseMatrix', 'ImmutableMatrix', 'SparseMatrix', 'MatrixSlice', 'BlockDiagMatrix', 'BlockMatrix', 'FunctionMatrix', 'Identity', 'Inverse', 'MatAdd', 'MatMul', 'MatPow', 'MatrixExpr', 'MatrixSymbol', 'Trace', 'Transpose', 'ZeroMatrix', 'OneMatrix', 'blockcut', 'block_collapse', 'matrix_symbols', 'Adjoint', 'hadamard_product', 'HadamardProduct', 'HadamardPower', 'Determinant', 'det', 'diagonalize_vector', 'DiagMatrix', 'DiagonalMatrix', 'DiagonalOf', 'trace', 'DotProduct', 'kronecker_product', 'KroneckerProduct', 'PermutationMatrix', 'MatrixPermute', 'Permanent', 'per', # sympy.geometry 'Point', 'Point2D', 'Point3D', 'Line', 'Ray', 'Segment', 'Line2D', 'Segment2D', 'Ray2D', 'Line3D', 'Segment3D', 'Ray3D', 'Plane', 'Ellipse', 'Circle', 'Polygon', 'RegularPolygon', 'Triangle', 'rad', 'deg', 'are_similar', 'centroid', 'convex_hull', 'idiff', 'intersection', 'closest_points', 'farthest_points', 'GeometryError', 'Curve', 'Parabola', # sympy.utilities 'flatten', 'group', 'take', 'subsets', 'variations', 'numbered_symbols', 'cartes', 'capture', 'dict_merge', 'postorder_traversal', 'interactive_traversal', 'prefixes', 'postfixes', 'sift', 'topological_sort', 'unflatten', 'has_dups', 'has_variety', 'reshape', 'default_sort_key', 'ordered', 'rotations', 'filldedent', 'lambdify', 'source', 'threaded', 'xthreaded', 'public', 'memoize_property', 'test', 'doctest', 'timed', # sympy.integrals 'integrate', 'Integral', 'line_integrate', 'mellin_transform', 'inverse_mellin_transform', 'MellinTransform', 'InverseMellinTransform', 'laplace_transform', 'inverse_laplace_transform', 'LaplaceTransform', 'InverseLaplaceTransform', 'fourier_transform', 'inverse_fourier_transform', 'FourierTransform', 'InverseFourierTransform', 'sine_transform', 'inverse_sine_transform', 'SineTransform', 'InverseSineTransform', 'cosine_transform', 'inverse_cosine_transform', 'CosineTransform', 'InverseCosineTransform', 'hankel_transform', 'inverse_hankel_transform', 'HankelTransform', 'InverseHankelTransform', 'singularityintegrate', # sympy.tensor 'IndexedBase', 'Idx', 'Indexed', 'get_contraction_structure', 'get_indices', 'shape', 'MutableDenseNDimArray', 'ImmutableDenseNDimArray', 'MutableSparseNDimArray', 'ImmutableSparseNDimArray', 'NDimArray', 'tensorproduct', 'tensorcontraction', 'tensordiagonal', 'derive_by_array', 'permutedims', 'Array', 'DenseNDimArray', 'SparseNDimArray', # sympy.parsing 'parse_expr', # sympy.calculus 'euler_equations', 'singularities', 'is_increasing', 'is_strictly_increasing', 'is_decreasing', 'is_strictly_decreasing', 'is_monotonic', 'finite_diff_weights', 'apply_finite_diff', 'as_finite_diff', 'differentiate_finite', 'periodicity', 'not_empty_in', 'AccumBounds', 'is_convex', 'stationary_points', 'minimum', 'maximum', # sympy.algebras 'Quaternion', # sympy.printing 'pager_print', 'pretty', 'pretty_print', 'pprint', 'pprint_use_unicode', 'pprint_try_use_unicode', 'latex', 'print_latex', 'multiline_latex', 'mathml', 'print_mathml', 'python', 'print_python', 'pycode', 'ccode', 'print_ccode', 'glsl_code', 'print_glsl', 'cxxcode', 'fcode', 'print_fcode', 'rcode', 'print_rcode', 'jscode', 'print_jscode', 'julia_code', 'mathematica_code', 'octave_code', 'rust_code', 'print_gtk', 'preview', 'srepr', 'print_tree', 'StrPrinter', 'sstr', 'sstrrepr', 'TableForm', 'dotprint', 'maple_code', 'print_maple_code', # sympy.plotting 'plot', 'textplot', 'plot_backends', 'plot_implicit', 'plot_parametric', # sympy.interactive 'init_session', 'init_printing', # sympy.testing 'test', 'doctest', ] #===========================================================================# # # # XXX: The names below were importable before sympy 1.6 using # # # # from sympy import * # # # # This happened implicitly because there was no __all__ defined in this # # __init__.py file. Not every package is imported. The list matches what # # would have been imported before. It is possible that these packages will # # not be imported by a star-import from sympy in future. # # # #===========================================================================# __all__.extend([ 'algebras', 'assumptions', 'calculus', 'concrete', 'discrete', 'external', 'functions', 'geometry', 'interactive', 'multipledispatch', 'ntheory', 'parsing', 'plotting', 'polys', 'printing', 'release', 'strategies', 'tensor', 'utilities', ])
8bfd1c79b39c14ed581f6f60a0bb0b1260a10e603f9185a79af5c90a4a466718
from __future__ import print_function, division import random import itertools from typing import Sequence as tSequence, Union as tUnion, List as tList, Tuple as tTuple from sympy import (Matrix, MatrixSymbol, S, Indexed, Basic, Tuple, Range, Set, And, Eq, FiniteSet, ImmutableMatrix, Integer, igcd, Lambda, Mul, Dummy, IndexedBase, Add, Interval, oo, linsolve, eye, Or, Not, Intersection, factorial, Contains, Union, Expr, Function, exp, cacheit, sqrt, pi, gamma, Ge, Piecewise, Symbol, NonSquareMatrixError, EmptySet, ceiling, MatrixBase, ConditionSet, ones, zeros, Identity, Rational, Lt, Gt, Le, Ne, BlockMatrix, Sum) from sympy.core.relational import Relational from sympy.logic.boolalg import Boolean from sympy.utilities.exceptions import SymPyDeprecationWarning from sympy.utilities.iterables import strongly_connected_components from sympy.stats.joint_rv import JointDistribution from sympy.stats.joint_rv_types import JointDistributionHandmade from sympy.stats.rv import (RandomIndexedSymbol, random_symbols, RandomSymbol, _symbol_converter, _value_check, pspace, given, dependent, is_random, sample_iter, Distribution, Density) from sympy.stats.stochastic_process import StochasticPSpace from sympy.stats.symbolic_probability import Probability, Expectation from sympy.stats.frv_types import Bernoulli, BernoulliDistribution, FiniteRV from sympy.stats.drv_types import Poisson, PoissonDistribution from sympy.stats.crv_types import Normal, NormalDistribution, Gamma, GammaDistribution from sympy.core.sympify import _sympify, sympify __all__ = [ 'StochasticProcess', 'DiscreteTimeStochasticProcess', 'DiscreteMarkovChain', 'TransitionMatrixOf', 'StochasticStateSpaceOf', 'GeneratorMatrixOf', 'ContinuousMarkovChain', 'BernoulliProcess', 'PoissonProcess', 'WienerProcess', 'GammaProcess' ] @is_random.register(Indexed) def _(x): return is_random(x.base) @is_random.register(RandomIndexedSymbol) # type: ignore def _(x): return True def _set_converter(itr): """ Helper function for converting list/tuple/set to Set. If parameter is not an instance of list/tuple/set then no operation is performed. Returns ======= Set The argument converted to Set. Raises ====== TypeError If the argument is not an instance of list/tuple/set. """ if isinstance(itr, (list, tuple, set)): itr = FiniteSet(*itr) if not isinstance(itr, Set): raise TypeError("%s is not an instance of list/tuple/set."%(itr)) return itr def _state_converter(itr: tSequence) -> tUnion[Tuple, Range]: """ Helper function for converting list/tuple/set/Range/Tuple/FiniteSet to tuple/Range. """ if isinstance(itr, (Tuple, set, FiniteSet)): itr = Tuple(*(sympify(i) if isinstance(i, str) else i for i in itr)) elif isinstance(itr, (list, tuple)): # check if states are unique if len(set(itr)) != len(itr): raise ValueError('The state space must have unique elements.') itr = Tuple(*(sympify(i) if isinstance(i, str) else i for i in itr)) elif isinstance(itr, Range): # the only ordered set in sympy I know of # try to convert to tuple try: itr = Tuple(*(sympify(i) if isinstance(i, str) else i for i in itr)) except ValueError: pass else: raise TypeError("%s is not an instance of list/tuple/set/Range/Tuple/FiniteSet." % (itr)) return itr def _sym_sympify(arg): """ Converts an arbitrary expression to a type that can be used inside SymPy. As generally strings are unwise to use in the expressions, it returns the Symbol of argument if the string type argument is passed. Parameters ========= arg: The parameter to be converted to be used in Sympy. Returns ======= The converted parameter. """ if isinstance(arg, str): return Symbol(arg) else: return _sympify(arg) def _matrix_checks(matrix): if not isinstance(matrix, (Matrix, MatrixSymbol, ImmutableMatrix)): raise TypeError("Transition probabilities either should " "be a Matrix or a MatrixSymbol.") if matrix.shape[0] != matrix.shape[1]: raise NonSquareMatrixError("%s is not a square matrix"%(matrix)) if isinstance(matrix, Matrix): matrix = ImmutableMatrix(matrix.tolist()) return matrix class StochasticProcess(Basic): """ Base class for all the stochastic processes whether discrete or continuous. Parameters ========== sym: Symbol or str state_space: Set The state space of the stochastic process, by default S.Reals. For discrete sets it is zero indexed. See Also ======== DiscreteTimeStochasticProcess """ index_set = S.Reals def __new__(cls, sym, state_space=S.Reals, **kwargs): sym = _symbol_converter(sym) state_space = _set_converter(state_space) return Basic.__new__(cls, sym, state_space) @property def symbol(self): return self.args[0] @property def state_space(self) -> tUnion[FiniteSet, Range]: if not isinstance(self.args[1], (FiniteSet, Range)): return FiniteSet(*self.args[1]) return self.args[1] def _deprecation_warn_distribution(self): SymPyDeprecationWarning( feature="Calling distribution with RandomIndexedSymbol", useinstead="distribution with just timestamp as argument", issue=20078, deprecated_since_version="1.7.1" ).warn() def distribution(self, key=None): if key is None: self._deprecation_warn_distribution() return Distribution() def density(self, x): return Density() def __call__(self, time): """ Overridden in ContinuousTimeStochasticProcess. """ raise NotImplementedError("Use [] for indexing discrete time stochastic process.") def __getitem__(self, time): """ Overridden in DiscreteTimeStochasticProcess. """ raise NotImplementedError("Use () for indexing continuous time stochastic process.") def probability(self, condition): raise NotImplementedError() def joint_distribution(self, *args): """ Computes the joint distribution of the random indexed variables. Parameters ========== args: iterable The finite list of random indexed variables/the key of a stochastic process whose joint distribution has to be computed. Returns ======= JointDistribution The joint distribution of the list of random indexed variables. An unevaluated object is returned if it is not possible to compute the joint distribution. Raises ====== ValueError: When the arguments passed are not of type RandomIndexSymbol or Number. """ args = list(args) for i, arg in enumerate(args): if S(arg).is_Number: if self.index_set.is_subset(S.Integers): args[i] = self.__getitem__(arg) else: args[i] = self.__call__(arg) elif not isinstance(arg, RandomIndexedSymbol): raise ValueError("Expected a RandomIndexedSymbol or " "key not %s"%(type(arg))) if args[0].pspace.distribution == Distribution(): return JointDistribution(*args) density = Lambda(tuple(args), expr=Mul.fromiter(arg.pspace.process.density(arg) for arg in args)) return JointDistributionHandmade(density) def expectation(self, condition, given_condition): raise NotImplementedError("Abstract method for expectation queries.") def sample(self): raise NotImplementedError("Abstract method for sampling queries.") class DiscreteTimeStochasticProcess(StochasticProcess): """ Base class for all discrete stochastic processes. """ def __getitem__(self, time): """ For indexing discrete time stochastic processes. Returns ======= RandomIndexedSymbol """ time = sympify(time) if not time.is_symbol and time not in self.index_set: raise IndexError("%s is not in the index set of %s"%(time, self.symbol)) idx_obj = Indexed(self.symbol, time) pspace_obj = StochasticPSpace(self.symbol, self, self.distribution(time)) return RandomIndexedSymbol(idx_obj, pspace_obj) class ContinuousTimeStochasticProcess(StochasticProcess): """ Base class for all continuous time stochastic process. """ def __call__(self, time): """ For indexing continuous time stochastic processes. Returns ======= RandomIndexedSymbol """ time = sympify(time) if not time.is_symbol and time not in self.index_set: raise IndexError("%s is not in the index set of %s"%(time, self.symbol)) func_obj = Function(self.symbol)(time) pspace_obj = StochasticPSpace(self.symbol, self, self.distribution(time)) return RandomIndexedSymbol(func_obj, pspace_obj) class TransitionMatrixOf(Boolean): """ Assumes that the matrix is the transition matrix of the process. """ def __new__(cls, process, matrix): if not isinstance(process, DiscreteMarkovChain): raise ValueError("Currently only DiscreteMarkovChain " "support TransitionMatrixOf.") matrix = _matrix_checks(matrix) return Basic.__new__(cls, process, matrix) process = property(lambda self: self.args[0]) matrix = property(lambda self: self.args[1]) class GeneratorMatrixOf(TransitionMatrixOf): """ Assumes that the matrix is the generator matrix of the process. """ def __new__(cls, process, matrix): if not isinstance(process, ContinuousMarkovChain): raise ValueError("Currently only ContinuousMarkovChain " "support GeneratorMatrixOf.") matrix = _matrix_checks(matrix) return Basic.__new__(cls, process, matrix) class StochasticStateSpaceOf(Boolean): def __new__(cls, process, state_space): if not isinstance(process, (DiscreteMarkovChain, ContinuousMarkovChain)): raise ValueError("Currently only DiscreteMarkovChain and ContinuousMarkovChain " "support StochasticStateSpaceOf.") state_space = _state_converter(state_space) if isinstance(state_space, Range): ss_size = ceiling((state_space.stop - state_space.start) / state_space.step) else: ss_size = len(state_space) state_index = Range(ss_size) return Basic.__new__(cls, process, state_index) process = property(lambda self: self.args[0]) state_index = property(lambda self: self.args[1]) class MarkovProcess(StochasticProcess): """ Contains methods that handle queries common to Markov processes. """ @property def number_of_states(self) -> tUnion[Integer, Symbol]: """ The number of states in the Markov Chain. """ return _sympify(self.args[2].shape[0]) @property def _state_index(self) -> Range: """ Returns state index as Range. """ return self.args[1] @classmethod def _sanity_checks(cls, state_space, trans_probs): # Try to never have None as state_space or trans_probs. # This helps a lot if we get it done at the start. if (state_space is None) and (trans_probs is None): _n = Dummy('n', integer=True, nonnegative=True) state_space = _state_converter(Range(_n)) trans_probs = _matrix_checks(MatrixSymbol('_T', _n, _n)) elif state_space is None: trans_probs = _matrix_checks(trans_probs) state_space = _state_converter(Range(trans_probs.shape[0])) elif trans_probs is None: state_space = _state_converter(state_space) if isinstance(state_space, Range): _n = ceiling((state_space.stop - state_space.start) / state_space.step) else: _n = len(state_space) trans_probs = MatrixSymbol('_T', _n, _n) else: state_space = _state_converter(state_space) trans_probs = _matrix_checks(trans_probs) # Range object doesn't want to give a symbolic size # so we do it ourselves. if isinstance(state_space, Range): ss_size = ceiling((state_space.stop - state_space.start) / state_space.step) else: ss_size = len(state_space) if ss_size != trans_probs.shape[0]: raise ValueError('The size of the state space and the number of ' 'rows of the transition matrix must be the same.') return state_space, trans_probs def _extract_information(self, given_condition): """ Helper function to extract information, like, transition matrix/generator matrix, state space, etc. """ if isinstance(self, DiscreteMarkovChain): trans_probs = self.transition_probabilities state_index = self._state_index elif isinstance(self, ContinuousMarkovChain): trans_probs = self.generator_matrix state_index = self._state_index if isinstance(given_condition, And): gcs = given_condition.args given_condition = S.true for gc in gcs: if isinstance(gc, TransitionMatrixOf): trans_probs = gc.matrix if isinstance(gc, StochasticStateSpaceOf): state_index = gc.state_index if isinstance(gc, Relational): given_condition = given_condition & gc if isinstance(given_condition, TransitionMatrixOf): trans_probs = given_condition.matrix given_condition = S.true if isinstance(given_condition, StochasticStateSpaceOf): state_index = given_condition.state_index given_condition = S.true return trans_probs, state_index, given_condition def _check_trans_probs(self, trans_probs, row_sum=1): """ Helper function for checking the validity of transition probabilities. """ if not isinstance(trans_probs, MatrixSymbol): rows = trans_probs.tolist() for row in rows: if (sum(row) - row_sum) != 0: raise ValueError("Values in a row must sum to %s. " "If you are using Float or floats then please use Rational."%(row_sum)) def _work_out_state_index(self, state_index, given_condition, trans_probs): """ Helper function to extract state space if there is a random symbol in the given condition. """ # if given condition is None, then there is no need to work out # state_space from random variables if given_condition != None: rand_var = list(given_condition.atoms(RandomSymbol) - given_condition.atoms(RandomIndexedSymbol)) if len(rand_var) == 1: state_index = rand_var[0].pspace.set # `not None` is `True`. So the old test fails for symbolic sizes. # Need to build the statement differently. sym_cond = not isinstance(self.number_of_states, (int, Integer)) cond1 = not sym_cond and len(state_index) != trans_probs.shape[0] if cond1: raise ValueError("state space is not compatible with the transition probabilities.") if not isinstance(trans_probs.shape[0], Symbol): state_index = FiniteSet(*[i for i in range(trans_probs.shape[0])]) return state_index @cacheit def _preprocess(self, given_condition, evaluate): """ Helper function for pre-processing the information. """ is_insufficient = False if not evaluate: # avoid pre-processing if the result is not to be evaluated return (True, None, None, None) # extracting transition matrix and state space trans_probs, state_index, given_condition = self._extract_information(given_condition) # given_condition does not have sufficient information # for computations if trans_probs is None or \ given_condition is None: is_insufficient = True else: # checking transition probabilities if isinstance(self, DiscreteMarkovChain): self._check_trans_probs(trans_probs, row_sum=1) elif isinstance(self, ContinuousMarkovChain): self._check_trans_probs(trans_probs, row_sum=0) # working out state space state_index = self._work_out_state_index(state_index, given_condition, trans_probs) return is_insufficient, trans_probs, state_index, given_condition def replace_with_index(self, condition): if isinstance(condition, Relational): lhs, rhs = condition.lhs, condition.rhs if not isinstance(lhs, RandomIndexedSymbol): lhs, rhs = rhs, lhs condition = type(condition)(self.index_of.get(lhs, lhs), self.index_of.get(rhs, rhs)) return condition def probability(self, condition, given_condition=None, evaluate=True, **kwargs): """ Handles probability queries for Markov process. Parameters ========== condition: Relational given_condition: Relational/And Returns ======= Probability If the information is not sufficient. Expr In all other cases. Note ==== Any information passed at the time of query overrides any information passed at the time of object creation like transition probabilities, state space. Pass the transition matrix using TransitionMatrixOf, generator matrix using GeneratorMatrixOf and state space using StochasticStateSpaceOf in given_condition using & or And. """ check, mat, state_index, new_given_condition = \ self._preprocess(given_condition, evaluate) rv = list(condition.atoms(RandomIndexedSymbol)) symbolic = False for sym in rv: if sym.key.is_symbol: symbolic = True break if check: return Probability(condition, new_given_condition) if isinstance(self, ContinuousMarkovChain): trans_probs = self.transition_probabilities(mat) elif isinstance(self, DiscreteMarkovChain): trans_probs = mat condition = self.replace_with_index(condition) given_condition = self.replace_with_index(given_condition) new_given_condition = self.replace_with_index(new_given_condition) if isinstance(condition, Relational): if isinstance(new_given_condition, And): gcs = new_given_condition.args else: gcs = (new_given_condition, ) min_key_rv = list(new_given_condition.atoms(RandomIndexedSymbol)) if len(min_key_rv): min_key_rv = min_key_rv[0] for r in rv: if min_key_rv.key.is_symbol or r.key.is_symbol: continue if min_key_rv.key > r.key: return Probability(condition) else: min_key_rv = None return Probability(condition) if symbolic: return self._symbolic_probability(condition, new_given_condition, rv, min_key_rv) if len(rv) > 1: rv[0] = condition.lhs rv[1] = condition.rhs if rv[0].key < rv[1].key: rv[0], rv[1] = rv[1], rv[0] if isinstance(condition, Gt): condition = Lt(condition.lhs, condition.rhs) elif isinstance(condition, Lt): condition = Gt(condition.lhs, condition.rhs) elif isinstance(condition, Ge): condition = Le(condition.lhs, condition.rhs) elif isinstance(condition, Le): condition = Ge(condition.lhs, condition.rhs) s = Rational(0, 1) n = len(self.state_space) if isinstance(condition, Eq) or isinstance(condition, Ne): for i in range(0, n): s += self.probability(Eq(rv[0], i), Eq(rv[1], i)) * self.probability(Eq(rv[1], i), new_given_condition) return s if isinstance(condition, Eq) else 1 - s else: upper = 0 greater = False if isinstance(condition, Ge) or isinstance(condition, Lt): upper = 1 if isinstance(condition, Gt) or isinstance(condition, Ge): greater = True for i in range(0, n): if i <= n//2: for j in range(0, i + upper): s += self.probability(Eq(rv[0], i), Eq(rv[1], j)) * self.probability(Eq(rv[1], j), new_given_condition) else: s += self.probability(Eq(rv[0], i), new_given_condition) for j in range(i + upper, n): s -= self.probability(Eq(rv[0], i), Eq(rv[1], j)) * self.probability(Eq(rv[1], j), new_given_condition) return s if greater else 1 - s rv = rv[0] states = condition.as_set() prob, gstate = dict(), None for gc in gcs: if gc.has(min_key_rv): if gc.has(Probability): p, gp = (gc.rhs, gc.lhs) if isinstance(gc.lhs, Probability) \ else (gc.lhs, gc.rhs) gr = gp.args[0] gset = Intersection(gr.as_set(), state_index) gstate = list(gset)[0] prob[gset] = p else: _, gstate = (gc.lhs.key, gc.rhs) if isinstance(gc.lhs, RandomIndexedSymbol) \ else (gc.rhs.key, gc.lhs) if any((k not in self.index_set) for k in (rv.key, min_key_rv.key)): raise IndexError("The timestamps of the process are not in it's index set.") states = Intersection(states, state_index) if not isinstance(self.number_of_states, Symbol) else states for state in Union(states, FiniteSet(gstate)): if not isinstance(state, (int, Integer)) or Ge(state, mat.shape[0]) is True: raise IndexError("No information is available for (%s, %s) in " "transition probabilities of shape, (%s, %s). " "State space is zero indexed." %(gstate, state, mat.shape[0], mat.shape[1])) if prob: gstates = Union(*prob.keys()) if len(gstates) == 1: gstate = list(gstates)[0] gprob = list(prob.values())[0] prob[gstates] = gprob elif len(gstates) == len(state_index) - 1: gstate = list(state_index - gstates)[0] gprob = S.One - sum(prob.values()) prob[state_index - gstates] = gprob else: raise ValueError("Conflicting information.") else: gprob = S.One if min_key_rv == rv: return sum([prob[FiniteSet(state)] for state in states]) if isinstance(self, ContinuousMarkovChain): return gprob * sum([trans_probs(rv.key - min_key_rv.key).__getitem__((gstate, state)) for state in states]) if isinstance(self, DiscreteMarkovChain): return gprob * sum([(trans_probs**(rv.key - min_key_rv.key)).__getitem__((gstate, state)) for state in states]) if isinstance(condition, Not): expr = condition.args[0] return S.One - self.probability(expr, given_condition, evaluate, **kwargs) if isinstance(condition, And): compute_later, state2cond, conds = [], dict(), condition.args for expr in conds: if isinstance(expr, Relational): ris = list(expr.atoms(RandomIndexedSymbol))[0] if state2cond.get(ris, None) is None: state2cond[ris] = S.true state2cond[ris] &= expr else: compute_later.append(expr) ris = [] for ri in state2cond: ris.append(ri) cset = Intersection(state2cond[ri].as_set(), state_index) if len(cset) == 0: return S.Zero state2cond[ri] = cset.as_relational(ri) sorted_ris = sorted(ris, key=lambda ri: ri.key) prod = self.probability(state2cond[sorted_ris[0]], given_condition, evaluate, **kwargs) for i in range(1, len(sorted_ris)): ri, prev_ri = sorted_ris[i], sorted_ris[i-1] if not isinstance(state2cond[ri], Eq): raise ValueError("The process is in multiple states at %s, unable to determine the probability."%(ri)) mat_of = TransitionMatrixOf(self, mat) if isinstance(self, DiscreteMarkovChain) else GeneratorMatrixOf(self, mat) prod *= self.probability(state2cond[ri], state2cond[prev_ri] & mat_of & StochasticStateSpaceOf(self, state_index), evaluate, **kwargs) for expr in compute_later: prod *= self.probability(expr, given_condition, evaluate, **kwargs) return prod if isinstance(condition, Or): return sum([self.probability(expr, given_condition, evaluate, **kwargs) for expr in condition.args]) raise NotImplementedError("Mechanism for handling (%s, %s) queries hasn't been " "implemented yet."%(condition, given_condition)) def _symbolic_probability(self, condition, new_given_condition, rv, min_key_rv): #Function to calculate probability for queries with symbols if isinstance(condition, Relational): curr_state = new_given_condition.rhs if isinstance(new_given_condition.lhs, RandomIndexedSymbol) \ else new_given_condition.lhs next_state = condition.rhs if isinstance(condition.lhs, RandomIndexedSymbol) \ else condition.lhs if isinstance(condition, Eq) or isinstance(condition, Ne): if isinstance(self, DiscreteMarkovChain): P = self.transition_probabilities**(rv[0].key - min_key_rv.key) else: P = exp(self.generator_matrix*(rv[0].key - min_key_rv.key)) prob = P[curr_state, next_state] if isinstance(condition, Eq) else 1 - P[curr_state, next_state] return Piecewise((prob, rv[0].key > min_key_rv.key), (Probability(condition), True)) else: upper = 1 greater = False if isinstance(condition, Ge) or isinstance(condition, Lt): upper = 0 if isinstance(condition, Gt) or isinstance(condition, Ge): greater = True k = Dummy('k') condition = Eq(condition.lhs, k) if isinstance(condition.lhs, RandomIndexedSymbol)\ else Eq(condition.rhs, k) total = Sum(self.probability(condition, new_given_condition), (k, next_state + upper, self.state_space._sup)) return Piecewise((total, rv[0].key > min_key_rv.key), (Probability(condition), True)) if greater\ else Piecewise((1 - total, rv[0].key > min_key_rv.key), (Probability(condition), True)) else: return Probability(condition, new_given_condition) def expectation(self, expr, condition=None, evaluate=True, **kwargs): """ Handles expectation queries for markov process. Parameters ========== expr: RandomIndexedSymbol, Relational, Logic Condition for which expectation has to be computed. Must contain a RandomIndexedSymbol of the process. condition: Relational, Logic The given conditions under which computations should be done. Returns ======= Expectation Unevaluated object if computations cannot be done due to insufficient information. Expr In all other cases when the computations are successful. Note ==== Any information passed at the time of query overrides any information passed at the time of object creation like transition probabilities, state space. Pass the transition matrix using TransitionMatrixOf, generator matrix using GeneratorMatrixOf and state space using StochasticStateSpaceOf in given_condition using & or And. """ check, mat, state_index, condition = \ self._preprocess(condition, evaluate) if check: return Expectation(expr, condition) rvs = random_symbols(expr) if isinstance(expr, Expr) and isinstance(condition, Eq) \ and len(rvs) == 1: # handle queries similar to E(f(X[i]), Eq(X[i-m], <some-state>)) condition=self.replace_with_index(condition) state_index=self.replace_with_index(state_index) rv = list(rvs)[0] lhsg, rhsg = condition.lhs, condition.rhs if not isinstance(lhsg, RandomIndexedSymbol): lhsg, rhsg = (rhsg, lhsg) if rhsg not in state_index: raise ValueError("%s state is not in the state space."%(rhsg)) if rv.key < lhsg.key: raise ValueError("Incorrect given condition is given, expectation " "time %s < time %s"%(rv.key, rv.key)) mat_of = TransitionMatrixOf(self, mat) if isinstance(self, DiscreteMarkovChain) else GeneratorMatrixOf(self, mat) cond = condition & mat_of & \ StochasticStateSpaceOf(self, state_index) func = lambda s: self.probability(Eq(rv, s), cond) * expr.subs(rv, self._state_index[s]) return sum([func(s) for s in state_index]) raise NotImplementedError("Mechanism for handling (%s, %s) queries hasn't been " "implemented yet."%(expr, condition)) class DiscreteMarkovChain(DiscreteTimeStochasticProcess, MarkovProcess): """ Represents a finite discrete time-homogeneous Markov chain. This type of Markov Chain can be uniquely characterised by its (ordered) state space and its one-step transition probability matrix. Parameters ========== sym: The name given to the Markov Chain state_space: Optional, by default, Range(n) trans_probs: Optional, by default, MatrixSymbol('_T', n, n) Examples ======== >>> from sympy.stats import DiscreteMarkovChain, TransitionMatrixOf, P, E >>> from sympy import Matrix, MatrixSymbol, Eq, symbols >>> T = Matrix([[0.5, 0.2, 0.3],[0.2, 0.5, 0.3],[0.2, 0.3, 0.5]]) >>> Y = DiscreteMarkovChain("Y", [0, 1, 2], T) >>> YS = DiscreteMarkovChain("Y") >>> Y.state_space FiniteSet(0, 1, 2) >>> Y.transition_probabilities Matrix([ [0.5, 0.2, 0.3], [0.2, 0.5, 0.3], [0.2, 0.3, 0.5]]) >>> TS = MatrixSymbol('T', 3, 3) >>> P(Eq(YS[3], 2), Eq(YS[1], 1) & TransitionMatrixOf(YS, TS)) T[0, 2]*T[1, 0] + T[1, 1]*T[1, 2] + T[1, 2]*T[2, 2] >>> P(Eq(Y[3], 2), Eq(Y[1], 1)).round(2) 0.36 Probabilities will be calculated based on indexes rather than state names. For example, with the Sunny-Cloudy-Rainy model with string state names: >>> from sympy.core.symbol import Str >>> Y = DiscreteMarkovChain("Y", [Str('Sunny'), Str('Cloudy'), Str('Rainy')], T) >>> P(Eq(Y[3], 2), Eq(Y[1], 1)).round(2) 0.36 This gives the same answer as the ``[0, 1, 2]`` state space. Currently, there is no support for state names within probability and expectation statements. Here is a work-around using ``Str``: >>> P(Eq(Str('Rainy'), Y[3]), Eq(Y[1], Str('Cloudy'))).round(2) 0.36 Symbol state names can also be used: >>> sunny, cloudy, rainy = symbols('Sunny, Cloudy, Rainy') >>> Y = DiscreteMarkovChain("Y", [sunny, cloudy, rainy], T) >>> P(Eq(Y[3], rainy), Eq(Y[1], cloudy)).round(2) 0.36 Expectations will be calculated as follows: >>> E(Y[3], Eq(Y[1], cloudy)) 0.38*Cloudy + 0.36*Rainy + 0.26*Sunny Probability of expressions with multiple RandomIndexedSymbols can also be calculated provided there is only 1 RandomIndexedSymbol in the given condition. It is always better to use Rational instead of floating point numbers for the probabilities in the transition matrix to avoid errors. >>> from sympy import Gt, Le, Rational >>> T = Matrix([[Rational(5, 10), Rational(3, 10), Rational(2, 10)], [Rational(2, 10), Rational(7, 10), Rational(1, 10)], [Rational(3, 10), Rational(3, 10), Rational(4, 10)]]) >>> Y = DiscreteMarkovChain("Y", [0, 1, 2], T) >>> P(Eq(Y[3], Y[1]), Eq(Y[0], 0)).round(3) 0.409 >>> P(Gt(Y[3], Y[1]), Eq(Y[0], 0)).round(2) 0.36 >>> P(Le(Y[15], Y[10]), Eq(Y[8], 2)).round(7) 0.6963328 Symbolic probability queries are also supported >>> from sympy import symbols, Matrix, Rational, Eq, Gt >>> from sympy.stats import P, DiscreteMarkovChain >>> a, b, c, d = symbols('a b c d') >>> T = Matrix([[Rational(1, 10), Rational(4, 10), Rational(5, 10)], [Rational(3, 10), Rational(4, 10), Rational(3, 10)], [Rational(7, 10), Rational(2, 10), Rational(1, 10)]]) >>> Y = DiscreteMarkovChain("Y", [0, 1, 2], T) >>> query = P(Eq(Y[a], b), Eq(Y[c], d)) >>> query.subs({a:10 ,b:2, c:5, d:1}).round(4) 0.3096 >>> P(Eq(Y[10], 2), Eq(Y[5], 1)).evalf().round(4) 0.3096 >>> query_gt = P(Gt(Y[a], b), Eq(Y[c], d)) >>> query_gt.subs({a:21, b:0, c:5, d:0}).evalf().round(5) 0.64705 >>> P(Gt(Y[21], 0), Eq(Y[5], 0)).round(5) 0.64705 There is limited support for arbitrarily sized states: >>> n = symbols('n', nonnegative=True, integer=True) >>> T = MatrixSymbol('T', n, n) >>> Y = DiscreteMarkovChain("Y", trans_probs=T) >>> Y.state_space Range(0, n, 1) >>> query = P(Eq(Y[a], b), Eq(Y[c], d)) >>> query.subs({a:10, b:2, c:5, d:1}) (T**5)[1, 2] References ========== .. [1] https://en.wikipedia.org/wiki/Markov_chain#Discrete-time_Markov_chain .. [2] https://www.dartmouth.edu/~chance/teaching_aids/books_articles/probability_book/Chapter11.pdf """ index_set = S.Naturals0 def __new__(cls, sym, state_space=None, trans_probs=None): # type: (Basic, tUnion[str, Symbol], tSequence, tUnion[MatrixBase, MatrixSymbol]) -> DiscreteMarkovChain sym = _symbol_converter(sym) state_space, trans_probs = MarkovProcess._sanity_checks(state_space, trans_probs) obj = Basic.__new__(cls, sym, state_space, trans_probs) indices = dict() if isinstance(obj.number_of_states, Integer): for index, state in enumerate(obj._state_index): indices[state] = index obj.index_of = indices return obj @property def transition_probabilities(self) -> tUnion[MatrixBase, MatrixSymbol]: """ Transition probabilities of discrete Markov chain, either an instance of Matrix or MatrixSymbol. """ return self.args[2] def communication_classes(self) -> tList[tTuple[tList[Basic], Boolean, Integer]]: """ Returns the list of communication classes that partition the states of the markov chain. A communication class is defined to be a set of states such that every state in that set is reachable from every other state in that set. Due to its properties this forms a class in the mathematical sense. Communication classes are also known as recurrence classes. Returns ======= classes The ``classes`` are a list of tuples. Each tuple represents a single communication class with its properties. The first element in the tuple is the list of states in the class, the second element is whether the class is recurrent and the third element is the period of the communication class. Examples ======== >>> from sympy.stats import DiscreteMarkovChain >>> from sympy import Matrix >>> T = Matrix([[0, 1, 0], ... [1, 0, 0], ... [1, 0, 0]]) >>> X = DiscreteMarkovChain('X', [1, 2, 3], T) >>> classes = X.communication_classes() >>> for states, is_recurrent, period in classes: ... states, is_recurrent, period ([1, 2], True, 2) ([3], False, 1) From this we can see that states ``1`` and ``2`` communicate, are recurrent and have a period of 2. We can also see state ``3`` is transient with a period of 1. Notes ===== The algorithm used is of order ``O(n**2)`` where ``n`` is the number of states in the markov chain. It uses Tarjan's algorithm to find the classes themselves and then it uses a breadth-first search algorithm to find each class's periodicity. Most of the algorithm's components approach ``O(n)`` as the matrix becomes more and more sparse. References ========== .. [1] http://www.columbia.edu/~ww2040/4701Sum07/4701-06-Notes-MCII.pdf .. [2] http://cecas.clemson.edu/~shierd/Shier/markov.pdf .. [3] https://ujcontent.uj.ac.za/vital/access/services/Download/uj:7506/CONTENT1 .. [4] https://www.mathworks.com/help/econ/dtmc.classify.html """ n = self.number_of_states T = self.transition_probabilities if isinstance(T, MatrixSymbol): raise NotImplementedError("Cannot perform the operation with a symbolic matrix.") # begin Tarjan's algorithm V = Range(n) # don't use state names. Rather use state # indexes since we use them for matrix # indexing here and later onward E = [(i, j) for i in V for j in V if T[i, j] != 0] classes = strongly_connected_components((V, E)) # end Tarjan's algorithm recurrence = [] periods = [] for class_ in classes: # begin recurrent check (similar to self._check_trans_probs()) submatrix = T[class_, class_] # get the submatrix with those states is_recurrent = S.true rows = submatrix.tolist() for row in rows: if (sum(row) - 1) != 0: is_recurrent = S.false break recurrence.append(is_recurrent) # end recurrent check # begin breadth-first search non_tree_edge_values = set() visited = {class_[0]} newly_visited = {class_[0]} level = {class_[0]: 0} current_level = 0 done = False # imitate a do-while loop while not done: # runs at most len(class_) times done = len(visited) == len(class_) current_level += 1 # this loop and the while loop above run a combined len(class_) number of times. # so this triple nested loop runs through each of the n states once. for i in newly_visited: # the loop below runs len(class_) number of times # complexity is around about O(n * avg(len(class_))) newly_visited = {j for j in class_ if T[i, j] != 0} new_tree_edges = newly_visited.difference(visited) for j in new_tree_edges: level[j] = current_level new_non_tree_edges = newly_visited.intersection(visited) new_non_tree_edge_values = {level[i]-level[j]+1 for j in new_non_tree_edges} non_tree_edge_values = non_tree_edge_values.union(new_non_tree_edge_values) visited = visited.union(new_tree_edges) # igcd needs at least 2 arguments positive_ntev = {val_e for val_e in non_tree_edge_values if val_e > 0} if len(positive_ntev) == 0: periods.append(len(class_)) elif len(positive_ntev) == 1: periods.append(positive_ntev.pop()) else: periods.append(igcd(*positive_ntev)) # end breadth-first search # convert back to the user's state names classes = [[self._state_index[i] for i in class_] for class_ in classes] return sympify(list(zip(classes, recurrence, periods))) def fundamental_matrix(self): """ Each entry fundamental matrix can be interpreted as the expected number of times the chains is in state j if it started in state i. References ========== .. [1] https://lips.cs.princeton.edu/the-fundamental-matrix-of-a-finite-markov-chain/ """ _, _, _, Q = self.decompose() if Q.shape[0] > 0: # if non-ergodic I = eye(Q.shape[0]) if (I - Q).det() == 0: raise ValueError("The fundamental matrix doesn't exist.") return (I - Q).inv().as_immutable() else: # if ergodic P = self.transition_probabilities I = eye(P.shape[0]) w = self.fixed_row_vector() W = Matrix([list(w) for i in range(0, P.shape[0])]) if (I - P + W).det() == 0: raise ValueError("The fundamental matrix doesn't exist.") return (I - P + W).inv().as_immutable() def absorbing_probabilities(self): """ Computes the absorbing probabilities, i.e., the ij-th entry of the matrix denotes the probability of Markov chain being absorbed in state j starting from state i. """ _, _, R, _ = self.decompose() N = self.fundamental_matrix() if R is None or N is None: return None return N*R def absorbing_probabilites(self): SymPyDeprecationWarning( feature="absorbing_probabilites", useinstead="absorbing_probabilities", issue=20042, deprecated_since_version="1.7" ).warn() return self.absorbing_probabilities() def is_regular(self): tuples = self.communication_classes() if len(tuples) == 0: return S.false # not defined for a 0x0 matrix classes, _, periods = list(zip(*tuples)) return And(len(classes) == 1, periods[0] == 1) def is_ergodic(self): tuples = self.communication_classes() if len(tuples) == 0: return S.false # not defined for a 0x0 matrix classes, _, _ = list(zip(*tuples)) return S(len(classes) == 1) def is_absorbing_state(self, state): trans_probs = self.transition_probabilities if isinstance(trans_probs, ImmutableMatrix) and \ state < trans_probs.shape[0]: return S(trans_probs[state, state]) is S.One def is_absorbing_chain(self): states, A, B, C = self.decompose() r = A.shape[0] return And(r > 0, A == Identity(r).as_explicit()) def stationary_distribution(self, condition_set=False) -> tUnion[ImmutableMatrix, ConditionSet, Lambda]: """ The stationary distribution is any row vector, p, that solves p = pP, is row stochastic and each element in p must be nonnegative. That means in matrix form: :math:`(P-I)^T p^T = 0` and :math:`(1, ..., 1) p = 1` where ``P`` is the one-step transition matrix. All time-homogeneous Markov Chains with a finite state space have at least one stationary distribution. In addition, if a finite time-homogeneous Markov Chain is irreducible, the stationary distribution is unique. Parameters ========== condition_set : bool If the chain has a symbolic size or transition matrix, it will return a ``Lambda`` if ``False`` and return a ``ConditionSet`` if ``True``. Examples ======== >>> from sympy.stats import DiscreteMarkovChain >>> from sympy import Matrix, S An irreducible Markov Chain >>> T = Matrix([[S(1)/2, S(1)/2, 0], ... [S(4)/5, S(1)/5, 0], ... [1, 0, 0]]) >>> X = DiscreteMarkovChain('X', trans_probs=T) >>> X.stationary_distribution() Matrix([[8/13, 5/13, 0]]) A reducible Markov Chain >>> T = Matrix([[S(1)/2, S(1)/2, 0], ... [S(4)/5, S(1)/5, 0], ... [0, 0, 1]]) >>> X = DiscreteMarkovChain('X', trans_probs=T) >>> X.stationary_distribution() Matrix([[8/13 - 8*tau0/13, 5/13 - 5*tau0/13, tau0]]) >>> Y = DiscreteMarkovChain('Y') >>> Y.stationary_distribution() Lambda((wm, _T), Eq(wm*_T, wm)) >>> Y.stationary_distribution(condition_set=True) ConditionSet(wm, Eq(wm*_T, wm)) References ========== .. [1] https://www.probabilitycourse.com/chapter11/11_2_6_stationary_and_limiting_distributions.php .. [2] https://galton.uchicago.edu/~yibi/teaching/stat317/2014/Lectures/Lecture4_6up.pdf See Also ======== sympy.stats.DiscreteMarkovChain.limiting_distribution """ trans_probs = self.transition_probabilities n = self.number_of_states if n == 0: return ImmutableMatrix(Matrix([[]])) # symbolic matrix version if isinstance(trans_probs, MatrixSymbol): wm = MatrixSymbol('wm', 1, n) if condition_set: return ConditionSet(wm, Eq(wm * trans_probs, wm)) else: return Lambda((wm, trans_probs), Eq(wm * trans_probs, wm)) # numeric matrix version a = Matrix(trans_probs - Identity(n)).T a[0, 0:n] = ones(1, n) b = zeros(n, 1) b[0, 0] = 1 soln = list(linsolve((a, b)))[0] return ImmutableMatrix([[sol for sol in soln]]) def fixed_row_vector(self): """ A wrapper for ``stationary_distribution()``. """ return self.stationary_distribution() @property def limiting_distribution(self): """ The fixed row vector is the limiting distribution of a discrete Markov chain. """ return self.fixed_row_vector() def decompose(self) -> tTuple[tList[Basic], ImmutableMatrix, ImmutableMatrix, ImmutableMatrix]: """ Decomposes the transition matrix into submatrices with special properties. The transition matrix can be decomposed into 4 submatrices: - A - the submatrix from recurrent states to recurrent states. - B - the submatrix from transient to recurrent states. - C - the submatrix from transient to transient states. - O - the submatrix of zeros for recurrent to transient states. Returns ======= states, A, B, C ``states`` - a list of state names with the first being the recurrent states and the last being the transient states in the order of the row names of A and then the row names of C. ``A`` - the submatrix from recurrent states to recurrent states. ``B`` - the submatrix from transient to recurrent states. ``C`` - the submatrix from transient to transient states. Examples ======== >>> from sympy.stats import DiscreteMarkovChain >>> from sympy import Matrix, S One can decompose this chain for example: >>> T = Matrix([[S(1)/2, S(1)/2, 0, 0, 0], ... [S(2)/5, S(1)/5, S(2)/5, 0, 0], ... [0, 0, 1, 0, 0], ... [0, 0, S(1)/2, S(1)/2, 0], ... [S(1)/2, 0, 0, 0, S(1)/2]]) >>> X = DiscreteMarkovChain('X', trans_probs=T) >>> states, A, B, C = X.decompose() >>> states [2, 0, 1, 3, 4] >>> A # recurrent to recurrent Matrix([[1]]) >>> B # transient to recurrent Matrix([ [ 0], [2/5], [1/2], [ 0]]) >>> C # transient to transient Matrix([ [1/2, 1/2, 0, 0], [2/5, 1/5, 0, 0], [ 0, 0, 1/2, 0], [1/2, 0, 0, 1/2]]) This means that state 2 is the only absorbing state (since A is a 1x1 matrix). B is a 4x1 matrix since the 4 remaining transient states all merge into reccurent state 2. And C is the 4x4 matrix that shows how the transient states 0, 1, 3, 4 all interact. See Also ======== sympy.stats.DiscreteMarkovChain.communication_classes sympy.stats.DiscreteMarkovChain.canonical_form References ========== .. [1] https://en.wikipedia.org/wiki/Absorbing_Markov_chain .. [2] http://people.brandeis.edu/~igusa/Math56aS08/Math56a_S08_notes015.pdf """ trans_probs = self.transition_probabilities classes = self.communication_classes() r_states = [] t_states = [] for states, recurrent, period in classes: if recurrent: r_states += states else: t_states += states states = r_states + t_states indexes = [self.index_of[state] for state in states] A = Matrix(len(r_states), len(r_states), lambda i, j: trans_probs[indexes[i], indexes[j]]) B = Matrix(len(t_states), len(r_states), lambda i, j: trans_probs[indexes[len(r_states) + i], indexes[j]]) C = Matrix(len(t_states), len(t_states), lambda i, j: trans_probs[indexes[len(r_states) + i], indexes[len(r_states) + j]]) return states, A.as_immutable(), B.as_immutable(), C.as_immutable() def canonical_form(self) -> tTuple[tList[Basic], ImmutableMatrix]: """ Reorders the one-step transition matrix so that recurrent states appear first and transient states appear last. Other representations include inserting transient states first and recurrent states last. Returns ======= states, P_new ``states`` is the list that describes the order of the new states in the matrix so that the ith element in ``states`` is the state of the ith row of A. ``P_new`` is the new transition matrix in canonical form. Examples ======== >>> from sympy.stats import DiscreteMarkovChain >>> from sympy import Matrix, S You can convert your chain into canonical form: >>> T = Matrix([[S(1)/2, S(1)/2, 0, 0, 0], ... [S(2)/5, S(1)/5, S(2)/5, 0, 0], ... [0, 0, 1, 0, 0], ... [0, 0, S(1)/2, S(1)/2, 0], ... [S(1)/2, 0, 0, 0, S(1)/2]]) >>> X = DiscreteMarkovChain('X', list(range(1, 6)), trans_probs=T) >>> states, new_matrix = X.canonical_form() >>> states [3, 1, 2, 4, 5] >>> new_matrix Matrix([ [ 1, 0, 0, 0, 0], [ 0, 1/2, 1/2, 0, 0], [2/5, 2/5, 1/5, 0, 0], [1/2, 0, 0, 1/2, 0], [ 0, 1/2, 0, 0, 1/2]]) The new states are [3, 1, 2, 4, 5] and you can create a new chain with this and its canonical form will remain the same (since it is already in canonical form). >>> X = DiscreteMarkovChain('X', states, new_matrix) >>> states, new_matrix = X.canonical_form() >>> states [3, 1, 2, 4, 5] >>> new_matrix Matrix([ [ 1, 0, 0, 0, 0], [ 0, 1/2, 1/2, 0, 0], [2/5, 2/5, 1/5, 0, 0], [1/2, 0, 0, 1/2, 0], [ 0, 1/2, 0, 0, 1/2]]) This is not limited to absorbing chains: >>> T = Matrix([[0, 5, 5, 0, 0], ... [0, 0, 0, 10, 0], ... [5, 0, 5, 0, 0], ... [0, 10, 0, 0, 0], ... [0, 3, 0, 3, 4]])/10 >>> X = DiscreteMarkovChain('X', trans_probs=T) >>> states, new_matrix = X.canonical_form() >>> states [1, 3, 0, 2, 4] >>> new_matrix Matrix([ [ 0, 1, 0, 0, 0], [ 1, 0, 0, 0, 0], [ 1/2, 0, 0, 1/2, 0], [ 0, 0, 1/2, 1/2, 0], [3/10, 3/10, 0, 0, 2/5]]) See Also ======== sympy.stats.DiscreteMarkovChain.communication_classes sympy.stats.DiscreteMarkovChain.decompose References ========== .. [1] https://onlinelibrary.wiley.com/doi/pdf/10.1002/9780470316887.app1 .. [2] http://www.columbia.edu/~ww2040/6711F12/lect1023big.pdf """ states, A, B, C = self.decompose() O = zeros(A.shape[0], C.shape[1]) return states, BlockMatrix([[A, O], [B, C]]).as_explicit() def sample(self): """ Returns ======= sample: iterator object iterator object containing the sample """ if not isinstance(self.transition_probabilities, (Matrix, ImmutableMatrix)): raise ValueError("Transition Matrix must be provided for sampling") Tlist = self.transition_probabilities.tolist() samps = [random.choice(list(self.state_space))] yield samps[0] time = 1 densities = {} for state in self.state_space: states = list(self.state_space) densities[state] = {states[i]: Tlist[state][i] for i in range(len(states))} while time < S.Infinity: samps.append((next(sample_iter(FiniteRV("_", densities[samps[time - 1]]))))) yield samps[time] time += 1 class ContinuousMarkovChain(ContinuousTimeStochasticProcess, MarkovProcess): """ Represents continuous time Markov chain. Parameters ========== sym: Symbol/str state_space: Set Optional, by default, S.Reals gen_mat: Matrix/ImmutableMatrix/MatrixSymbol Optional, by default, None Examples ======== >>> from sympy.stats import ContinuousMarkovChain, P >>> from sympy import Matrix, S, Eq, Gt >>> G = Matrix([[-S(1), S(1)], [S(1), -S(1)]]) >>> C = ContinuousMarkovChain('C', state_space=[0, 1], gen_mat=G) >>> C.limiting_distribution() Matrix([[1/2, 1/2]]) >>> C.state_space FiniteSet(0, 1) >>> C.generator_matrix Matrix([ [-1, 1], [ 1, -1]]) Probability queries are supported >>> P(Eq(C(1.96), 0), Eq(C(0.78), 1)).round(5) 0.45279 >>> P(Gt(C(1.7), 0), Eq(C(0.82), 1)).round(5) 0.58602 Probability of expressions with multiple RandomIndexedSymbols can also be calculated provided there is only 1 RandomIndexedSymbol in the given condition. It is always better to use Rational instead of floating point numbers for the probabilities in the generator matrix to avoid errors. >>> from sympy import Gt, Le, Rational >>> G = Matrix([[-S(1), Rational(1, 10), Rational(9, 10)], [Rational(2, 5), -S(1), Rational(3, 5)], [Rational(1, 2), Rational(1, 2), -S(1)]]) >>> C = ContinuousMarkovChain('C', state_space=[0, 1, 2], gen_mat=G) >>> P(Eq(C(3.92), C(1.75)), Eq(C(0.46), 0)).round(5) 0.37933 >>> P(Gt(C(3.92), C(1.75)), Eq(C(0.46), 0)).round(5) 0.34211 >>> P(Le(C(1.57), C(3.14)), Eq(C(1.22), 1)).round(4) 0.7143 Symbolic probability queries are also supported >>> from sympy import S, symbols, Matrix, Rational, Eq, Gt >>> from sympy.stats import P, ContinuousMarkovChain >>> a,b,c,d = symbols('a b c d') >>> G = Matrix([[-S(1), Rational(1, 10), Rational(9, 10)], [Rational(2, 5), -S(1), Rational(3, 5)], [Rational(1, 2), Rational(1, 2), -S(1)]]) >>> C = ContinuousMarkovChain('C', state_space=[0, 1, 2], gen_mat=G) >>> query = P(Eq(C(a), b), Eq(C(c), d)) >>> query.subs({a:3.65 ,b:2, c:1.78, d:1}).evalf().round(10) 0.4002723175 >>> P(Eq(C(3.65), 2), Eq(C(1.78), 1)).round(10) 0.4002723175 >>> query_gt = P(Gt(C(a), b), Eq(C(c), d)) >>> query_gt.subs({a:43.2 ,b:0, c:3.29, d:2}).evalf().round(10) 0.6832579186 >>> P(Gt(C(43.2), 0), Eq(C(3.29), 2)).round(10) 0.6832579186 References ========== .. [1] https://en.wikipedia.org/wiki/Markov_chain#Continuous-time_Markov_chain .. [2] http://u.math.biu.ac.il/~amirgi/CTMCnotes.pdf """ index_set = S.Reals def __new__(cls, sym, state_space=None, gen_mat=None): sym = _symbol_converter(sym) state_space, gen_mat = MarkovProcess._sanity_checks(state_space, gen_mat) obj = Basic.__new__(cls, sym, state_space, gen_mat) indices = dict() if isinstance(obj.number_of_states, Integer): for index, state in enumerate(obj.state_space): indices[state] = index obj.index_of = indices return obj @property def generator_matrix(self): return self.args[2] @cacheit def transition_probabilities(self, gen_mat=None): t = Dummy('t') if isinstance(gen_mat, (Matrix, ImmutableMatrix)) and \ gen_mat.is_diagonalizable(): # for faster computation use diagonalized generator matrix Q, D = gen_mat.diagonalize() return Lambda(t, Q*exp(t*D)*Q.inv()) if gen_mat != None: return Lambda(t, exp(t*gen_mat)) def limiting_distribution(self): gen_mat = self.generator_matrix if gen_mat is None: return None if isinstance(gen_mat, MatrixSymbol): wm = MatrixSymbol('wm', 1, gen_mat.shape[0]) return Lambda((wm, gen_mat), Eq(wm*gen_mat, wm)) w = IndexedBase('w') wi = [w[i] for i in range(gen_mat.shape[0])] wm = Matrix([wi]) eqs = (wm*gen_mat).tolist()[0] eqs.append(sum(wi) - 1) soln = list(linsolve(eqs, wi))[0] return ImmutableMatrix([[sol for sol in soln]]) class BernoulliProcess(DiscreteTimeStochasticProcess): """ The Bernoulli process consists of repeated independent Bernoulli process trials with the same parameter `p`. It's assumed that the probability `p` applies to every trial and that the outcomes of each trial are independent of all the rest. Therefore Bernoulli Processs is Discrete State and Discrete Time Stochastic Process. Parameters ========== sym: Symbol/str success: Integer/str The event which is considered to be success, by default is 1. failure: Integer/str The event which is considered to be failure, by default is 0. p: Real Number between 0 and 1 Represents the probability of getting success. Examples ======== >>> from sympy.stats import BernoulliProcess, P, E >>> from sympy import Eq, Gt >>> B = BernoulliProcess("B", p=0.7, success=1, failure=0) >>> B.state_space FiniteSet(0, 1) >>> (B.p).round(2) 0.70 >>> B.success 1 >>> B.failure 0 >>> X = B[1] + B[2] + B[3] >>> P(Eq(X, 0)).round(2) 0.03 >>> P(Eq(X, 2)).round(2) 0.44 >>> P(Eq(X, 4)).round(2) 0 >>> P(Gt(X, 1)).round(2) 0.78 >>> P(Eq(B[1], 0) & Eq(B[2], 1) & Eq(B[3], 0) & Eq(B[4], 1)).round(2) 0.04 >>> B.joint_distribution(B[1], B[2]) JointDistributionHandmade(Lambda((B[1], B[2]), Piecewise((0.7, Eq(B[1], 1)), (0.3, Eq(B[1], 0)), (0, True))*Piecewise((0.7, Eq(B[2], 1)), (0.3, Eq(B[2], 0)), (0, True)))) >>> E(2*B[1] + B[2]).round(2) 2.10 >>> P(B[1] < 1).round(2) 0.30 References ========== .. [1] https://en.wikipedia.org/wiki/Bernoulli_process .. [2] https://mathcs.clarku.edu/~djoyce/ma217/bernoulli.pdf """ index_set = S.Naturals0 def __new__(cls, sym, p, success=1, failure=0): _value_check(p >= 0 and p <= 1, 'Value of p must be between 0 and 1.') sym = _symbol_converter(sym) p = _sympify(p) success = _sym_sympify(success) failure = _sym_sympify(failure) return Basic.__new__(cls, sym, p, success, failure) @property def symbol(self): return self.args[0] @property def p(self): return self.args[1] @property def success(self): return self.args[2] @property def failure(self): return self.args[3] @property def state_space(self): return _set_converter([self.success, self.failure]) def distribution(self, key=None): if key is None: self._deprecation_warn_distribution() return BernoulliDistribution(self.p) return BernoulliDistribution(self.p, self.success, self.failure) def simple_rv(self, rv): return Bernoulli(rv.name, p=self.p, succ=self.success, fail=self.failure) def expectation(self, expr, condition=None, evaluate=True, **kwargs): """ Computes expectation. Parameters ========== expr: RandomIndexedSymbol, Relational, Logic Condition for which expectation has to be computed. Must contain a RandomIndexedSymbol of the process. condition: Relational, Logic The given conditions under which computations should be done. Returns ======= Expectation of the RandomIndexedSymbol. """ return _SubstituteRV._expectation(expr, condition, evaluate, **kwargs) def probability(self, condition, given_condition=None, evaluate=True, **kwargs): """ Computes probability. Parameters ========== condition: Relational Condition for which probability has to be computed. Must contain a RandomIndexedSymbol of the process. given_condition: Relational/And The given conditions under which computations should be done. Returns ======= Probability of the condition. """ return _SubstituteRV._probability(condition, given_condition, evaluate, **kwargs) def density(self, x): return Piecewise((self.p, Eq(x, self.success)), (1 - self.p, Eq(x, self.failure)), (S.Zero, True)) class _SubstituteRV: """ Internal class to handle the queries of expectation and probability by substitution. """ @staticmethod def _rvindexed_subs(expr, condition=None): """ Substitutes the RandomIndexedSymbol with the RandomSymbol with same name, distribution and probability as RandomIndexedSymbol. Parameters ========== expr: RandomIndexedSymbol, Relational, Logic Condition for which expectation has to be computed. Must contain a RandomIndexedSymbol of the process. condition: Relational, Logic The given conditions under which computations should be done. """ rvs_expr = random_symbols(expr) if len(rvs_expr) != 0: swapdict_expr = {} for rv in rvs_expr: if isinstance(rv, RandomIndexedSymbol): newrv = rv.pspace.process.simple_rv(rv) # substitute with equivalent simple rv swapdict_expr[rv] = newrv expr = expr.subs(swapdict_expr) rvs_cond = random_symbols(condition) if len(rvs_cond)!=0: swapdict_cond = {} for rv in rvs_cond: if isinstance(rv, RandomIndexedSymbol): newrv = rv.pspace.process.simple_rv(rv) swapdict_cond[rv] = newrv condition = condition.subs(swapdict_cond) return expr, condition @classmethod def _expectation(self, expr, condition=None, evaluate=True, **kwargs): """ Internal method for computing expectation of indexed RV. Parameters ========== expr: RandomIndexedSymbol, Relational, Logic Condition for which expectation has to be computed. Must contain a RandomIndexedSymbol of the process. condition: Relational, Logic The given conditions under which computations should be done. Returns ======= Expectation of the RandomIndexedSymbol. """ new_expr, new_condition = self._rvindexed_subs(expr, condition) if not is_random(new_expr): return new_expr new_pspace = pspace(new_expr) if new_condition is not None: new_expr = given(new_expr, new_condition) if new_expr.is_Add: # As E is Linear return Add(*[new_pspace.compute_expectation( expr=arg, evaluate=evaluate, **kwargs) for arg in new_expr.args]) return new_pspace.compute_expectation( new_expr, evaluate=evaluate, **kwargs) @classmethod def _probability(self, condition, given_condition=None, evaluate=True, **kwargs): """ Internal method for computing probability of indexed RV Parameters ========== condition: Relational Condition for which probability has to be computed. Must contain a RandomIndexedSymbol of the process. given_condition: Relational/And The given conditions under which computations should be done. Returns ======= Probability of the condition. """ new_condition, new_givencondition = self._rvindexed_subs(condition, given_condition) if isinstance(new_givencondition, RandomSymbol): condrv = random_symbols(new_condition) if len(condrv) == 1 and condrv[0] == new_givencondition: return BernoulliDistribution(self._probability(new_condition), 0, 1) if any([dependent(rv, new_givencondition) for rv in condrv]): return Probability(new_condition, new_givencondition) else: return self._probability(new_condition) if new_givencondition is not None and \ not isinstance(new_givencondition, (Relational, Boolean)): raise ValueError("%s is not a relational or combination of relationals" % (new_givencondition)) if new_givencondition == False or new_condition == False: return S.Zero if new_condition == True: return S.One if not isinstance(new_condition, (Relational, Boolean)): raise ValueError("%s is not a relational or combination of relationals" % (new_condition)) if new_givencondition is not None: # If there is a condition # Recompute on new conditional expr return self._probability(given(new_condition, new_givencondition, **kwargs), **kwargs) result = pspace(new_condition).probability(new_condition, **kwargs) if evaluate and hasattr(result, 'doit'): return result.doit() else: return result def get_timerv_swaps(expr, condition): """ Finds the appropriate interval for each time stamp in expr by parsing the given condition and returns intervals for each timestamp and dictionary that maps variable time-stamped Random Indexed Symbol to its corresponding Random Indexed variable with fixed time stamp. Parameters ========== expr: Sympy Expression Expression containing Random Indexed Symbols with variable time stamps condition: Relational/Boolean Expression Expression containing time bounds of variable time stamps in expr Examples ======== >>> from sympy.stats.stochastic_process_types import get_timerv_swaps, PoissonProcess >>> from sympy import symbols, Contains, Interval >>> x, t, d = symbols('x t d', positive=True) >>> X = PoissonProcess("X", 3) >>> get_timerv_swaps(x*X(t), Contains(t, Interval.Lopen(0, 1))) ([Interval.Lopen(0, 1)], {X(t): X(1)}) >>> get_timerv_swaps((X(t)**2 + X(d)**2), Contains(t, Interval.Lopen(0, 1)) ... & Contains(d, Interval.Ropen(1, 4))) # doctest: +SKIP ([Interval.Ropen(1, 4), Interval.Lopen(0, 1)], {X(d): X(3), X(t): X(1)}) Returns ======= intervals: list List of Intervals/FiniteSet on which each time stamp is defined rv_swap: dict Dictionary mapping variable time Random Indexed Symbol to constant time Random Indexed Variable """ if not isinstance(condition, (Relational, Boolean)): raise ValueError("%s is not a relational or combination of relationals" % (condition)) expr_syms = list(expr.atoms(RandomIndexedSymbol)) if isinstance(condition, (And, Or)): given_cond_args = condition.args else: # single condition given_cond_args = (condition, ) rv_swap = {} intervals = [] for expr_sym in expr_syms: for arg in given_cond_args: if arg.has(expr_sym.key) and isinstance(expr_sym.key, Symbol): intv = _set_converter(arg.args[1]) diff_key = intv._sup - intv._inf if diff_key == oo: raise ValueError("%s should have finite bounds" % str(expr_sym.name)) elif diff_key == S.Zero: # has singleton set diff_key = intv._sup rv_swap[expr_sym] = expr_sym.subs({expr_sym.key: diff_key}) intervals.append(intv) return intervals, rv_swap class CountingProcess(ContinuousTimeStochasticProcess): """ This class handles the common methods of the Counting Processes such as Poisson, Wiener and Gamma Processes """ index_set = _set_converter(Interval(0, oo)) @property def symbol(self): return self.args[0] def expectation(self, expr, condition=None, evaluate=True, **kwargs): """ Computes expectation Parameters ========== expr: RandomIndexedSymbol, Relational, Logic Condition for which expectation has to be computed. Must contain a RandomIndexedSymbol of the process. condition: Relational, Boolean The given conditions under which computations should be done, i.e, the intervals on which each variable time stamp in expr is defined Returns ======= Expectation of the given expr """ if condition is not None: intervals, rv_swap = get_timerv_swaps(expr, condition) # they are independent when they have non-overlapping intervals if len(intervals) == 1 or all(Intersection(*intv_comb) == EmptySet for intv_comb in itertools.combinations(intervals, 2)): if expr.is_Add: return Add.fromiter(self.expectation(arg, condition) for arg in expr.args) expr = expr.subs(rv_swap) else: return Expectation(expr, condition) return _SubstituteRV._expectation(expr, evaluate=evaluate, **kwargs) def _solve_argwith_tworvs(self, arg): if arg.args[0].key >= arg.args[1].key or isinstance(arg, Eq): diff_key = abs(arg.args[0].key - arg.args[1].key) rv = arg.args[0] arg = arg.__class__(rv.pspace.process(diff_key), 0) else: diff_key = arg.args[1].key - arg.args[0].key rv = arg.args[1] arg = arg.__class__(rv.pspace.process(diff_key), 0) return arg def _solve_numerical(self, condition, given_condition=None): if isinstance(condition, And): args_list = list(condition.args) else: args_list = [condition] if given_condition is not None: if isinstance(given_condition, And): args_list.extend(list(given_condition.args)) else: args_list.extend([given_condition]) # sort the args based on timestamp to get the independent increments in # each segment using all the condition args as well as given_condition args args_list = sorted(args_list, key=lambda x: x.args[0].key) result = [] cond_args = list(condition.args) if isinstance(condition, And) else [condition] if args_list[0] in cond_args and not (is_random(args_list[0].args[0]) and is_random(args_list[0].args[1])): result.append(_SubstituteRV._probability(args_list[0])) if is_random(args_list[0].args[0]) and is_random(args_list[0].args[1]): arg = self._solve_argwith_tworvs(args_list[0]) result.append(_SubstituteRV._probability(arg)) for i in range(len(args_list) - 1): curr, nex = args_list[i], args_list[i + 1] diff_key = nex.args[0].key - curr.args[0].key working_set = curr.args[0].pspace.process.state_space if curr.args[1] > nex.args[1]: #impossible condition so return 0 result.append(0) break if isinstance(curr, Eq): working_set = Intersection(working_set, Interval.Lopen(curr.args[1], oo)) else: working_set = Intersection(working_set, curr.as_set()) if isinstance(nex, Eq): working_set = Intersection(working_set, Interval(-oo, nex.args[1])) else: working_set = Intersection(working_set, nex.as_set()) if working_set == EmptySet: rv = Eq(curr.args[0].pspace.process(diff_key), 0) result.append(_SubstituteRV._probability(rv)) else: if working_set.is_finite_set: if isinstance(curr, Eq) and isinstance(nex, Eq): rv = Eq(curr.args[0].pspace.process(diff_key), len(working_set)) result.append(_SubstituteRV._probability(rv)) elif isinstance(curr, Eq) ^ isinstance(nex, Eq): result.append(Add.fromiter(_SubstituteRV._probability(Eq( curr.args[0].pspace.process(diff_key), x)) for x in range(len(working_set)))) else: n = len(working_set) result.append(Add.fromiter((n - x)*_SubstituteRV._probability(Eq( curr.args[0].pspace.process(diff_key), x)) for x in range(n))) else: result.append(_SubstituteRV._probability( curr.args[0].pspace.process(diff_key) <= working_set._sup - working_set._inf)) return Mul.fromiter(result) def probability(self, condition, given_condition=None, evaluate=True, **kwargs): """ Computes probability. Parameters ========== condition: Relational Condition for which probability has to be computed. Must contain a RandomIndexedSymbol of the process. given_condition: Relational, Boolean The given conditions under which computations should be done, i.e, the intervals on which each variable time stamp in expr is defined Returns ======= Probability of the condition """ check_numeric = True if isinstance(condition, (And, Or)): cond_args = condition.args else: cond_args = (condition, ) # check that condition args are numeric or not if not all(arg.args[0].key.is_number for arg in cond_args): check_numeric = False if given_condition is not None: check_given_numeric = True if isinstance(given_condition, (And, Or)): given_cond_args = given_condition.args else: given_cond_args = (given_condition, ) # check that given condition args are numeric or not if given_condition.has(Contains): check_given_numeric = False # Handle numerical queries if check_numeric and check_given_numeric: res = [] if isinstance(condition, Or): res.append(Add.fromiter(self._solve_numerical(arg, given_condition) for arg in condition.args)) if isinstance(given_condition, Or): res.append(Add.fromiter(self._solve_numerical(condition, arg) for arg in given_condition.args)) if res: return Add.fromiter(res) return self._solve_numerical(condition, given_condition) # No numeric queries, go by Contains?... then check that all the # given condition are in form of `Contains` if not all(arg.has(Contains) for arg in given_cond_args): raise ValueError("If given condition is passed with `Contains`, then " "please pass the evaluated condition with its corresponding information " "in terms of intervals of each time stamp to be passed in given condition.") intervals, rv_swap = get_timerv_swaps(condition, given_condition) # they are independent when they have non-overlapping intervals if len(intervals) == 1 or all(Intersection(*intv_comb) == EmptySet for intv_comb in itertools.combinations(intervals, 2)): if isinstance(condition, And): return Mul.fromiter(self.probability(arg, given_condition) for arg in condition.args) elif isinstance(condition, Or): return Add.fromiter(self.probability(arg, given_condition) for arg in condition.args) condition = condition.subs(rv_swap) else: return Probability(condition, given_condition) if check_numeric: return self._solve_numerical(condition) return _SubstituteRV._probability(condition, evaluate=evaluate, **kwargs) class PoissonProcess(CountingProcess): """ The Poisson process is a counting process. It is usually used in scenarios where we are counting the occurrences of certain events that appear to happen at a certain rate, but completely at random. Parameters ========== sym: Symbol/str lamda: Positive number Rate of the process, ``lamda > 0`` Examples ======== >>> from sympy.stats import PoissonProcess, P, E >>> from sympy import symbols, Eq, Ne, Contains, Interval >>> X = PoissonProcess("X", lamda=3) >>> X.state_space Naturals0 >>> X.lamda 3 >>> t1, t2 = symbols('t1 t2', positive=True) >>> P(X(t1) < 4) (9*t1**3/2 + 9*t1**2/2 + 3*t1 + 1)*exp(-3*t1) >>> P(Eq(X(t1), 2) | Ne(X(t1), 4), Contains(t1, Interval.Ropen(2, 4))) 1 - 36*exp(-6) >>> P(Eq(X(t1), 2) & Eq(X(t2), 3), Contains(t1, Interval.Lopen(0, 2)) ... & Contains(t2, Interval.Lopen(2, 4))) 648*exp(-12) >>> E(X(t1)) 3*t1 >>> E(X(t1)**2 + 2*X(t2), Contains(t1, Interval.Lopen(0, 1)) ... & Contains(t2, Interval.Lopen(1, 2))) 18 >>> P(X(3) < 1, Eq(X(1), 0)) exp(-6) >>> P(Eq(X(4), 3), Eq(X(2), 3)) exp(-6) >>> P(X(2) <= 3, X(1) > 1) 5*exp(-3) Merging two Poisson Processes >>> Y = PoissonProcess("Y", lamda=4) >>> Z = X + Y >>> Z.lamda 7 Splitting a Poisson Process into two independent Poisson Processes >>> N, M = Z.split(l1=2, l2=5) >>> N.lamda, M.lamda (2, 5) References ========== .. [1] https://www.probabilitycourse.com/chapter11/11_0_0_intro.php .. [2] https://en.wikipedia.org/wiki/Poisson_point_process """ def __new__(cls, sym, lamda): _value_check(lamda > 0, 'lamda should be a positive number.') sym = _symbol_converter(sym) lamda = _sympify(lamda) return Basic.__new__(cls, sym, lamda) @property def lamda(self): return self.args[1] @property def state_space(self): return S.Naturals0 def distribution(self, key): if isinstance(key, RandomIndexedSymbol): self._deprecation_warn_distribution() return PoissonDistribution(self.lamda*key.key) return PoissonDistribution(self.lamda*key) def density(self, x): return (self.lamda*x.key)**x / factorial(x) * exp(-(self.lamda*x.key)) def simple_rv(self, rv): return Poisson(rv.name, lamda=self.lamda*rv.key) def __add__(self, other): if not isinstance(other, PoissonProcess): raise ValueError("Only instances of Poisson Process can be merged") return PoissonProcess(Dummy(self.symbol.name + other.symbol.name), self.lamda + other.lamda) def split(self, l1, l2): if _sympify(l1 + l2) != self.lamda: raise ValueError("Sum of l1 and l2 should be %s" % str(self.lamda)) return PoissonProcess(Dummy("l1"), l1), PoissonProcess(Dummy("l2"), l2) class WienerProcess(CountingProcess): """ The Wiener process is a real valued continuous-time stochastic process. In physics it is used to study Brownian motion and therefore also known as Brownian Motion. Parameters ========== sym: Symbol/str Examples ======== >>> from sympy.stats import WienerProcess, P, E >>> from sympy import symbols, Contains, Interval >>> X = WienerProcess("X") >>> X.state_space Reals >>> t1, t2 = symbols('t1 t2', positive=True) >>> P(X(t1) < 7).simplify() erf(7*sqrt(2)/(2*sqrt(t1)))/2 + 1/2 >>> P((X(t1) > 2) | (X(t1) < 4), Contains(t1, Interval.Ropen(2, 4))).simplify() -erf(1)/2 + erf(2)/2 + 1 >>> E(X(t1)) 0 >>> E(X(t1) + 2*X(t2), Contains(t1, Interval.Lopen(0, 1)) ... & Contains(t2, Interval.Lopen(1, 2))) 0 References ========== .. [1] https://www.probabilitycourse.com/chapter11/11_4_0_brownian_motion_wiener_process.php .. [2] https://en.wikipedia.org/wiki/Wiener_process """ def __new__(cls, sym): sym = _symbol_converter(sym) return Basic.__new__(cls, sym) @property def state_space(self): return S.Reals def distribution(self, key): if isinstance(key, RandomIndexedSymbol): self._deprecation_warn_distribution() return NormalDistribution(0, sqrt(key.key)) return NormalDistribution(0, sqrt(key)) def density(self, x): return exp(-x**2/(2*x.key)) / (sqrt(2*pi)*sqrt(x.key)) def simple_rv(self, rv): return Normal(rv.name, 0, sqrt(rv.key)) class GammaProcess(CountingProcess): """ A Gamma process is a random process with independent gamma distributed increments. It is a pure-jump increasing Levy process. Parameters ========== sym: Symbol/str lamda: Positive number Jump size of the process, ``lamda > 0`` gamma: Positive number Rate of jump arrivals, ``gamma > 0`` Examples ======== >>> from sympy.stats import GammaProcess, E, P, variance >>> from sympy import symbols, Contains, Interval, Not >>> t, d, x, l, g = symbols('t d x l g', positive=True) >>> X = GammaProcess("X", l, g) >>> E(X(t)) g*t/l >>> variance(X(t)).simplify() g*t/l**2 >>> X = GammaProcess('X', 1, 2) >>> P(X(t) < 1).simplify() lowergamma(2*t, 1)/gamma(2*t) >>> P(Not((X(t) < 5) & (X(d) > 3)), Contains(t, Interval.Ropen(2, 4)) & ... Contains(d, Interval.Lopen(7, 8))).simplify() -4*exp(-3) + 472*exp(-8)/3 + 1 >>> E(X(2) + x*E(X(5))) 10*x + 4 References ========== .. [1] https://en.wikipedia.org/wiki/Gamma_process """ def __new__(cls, sym, lamda, gamma): _value_check(lamda > 0, 'lamda should be a positive number') _value_check(gamma > 0, 'gamma should be a positive number') sym = _symbol_converter(sym) gamma = _sympify(gamma) lamda = _sympify(lamda) return Basic.__new__(cls, sym, lamda, gamma) @property def lamda(self): return self.args[1] @property def gamma(self): return self.args[2] @property def state_space(self): return _set_converter(Interval(0, oo)) def distribution(self, key): if isinstance(key, RandomIndexedSymbol): self._deprecation_warn_distribution() return GammaDistribution(self.gamma*key.key, 1/self.lamda) return GammaDistribution(self.gamma*key, 1/self.lamda) def density(self, x): k = self.gamma*x.key theta = 1/self.lamda return x**(k - 1) * exp(-x/theta) / (gamma(k)*theta**k) def simple_rv(self, rv): return Gamma(rv.name, self.gamma*rv.key, 1/self.lamda)
cb5929126f1529b31d999033bf50ad083aa974d96cba1382c7caddfe25311ae4
from sympy import S, Basic, exp, multigamma, pi, prod from sympy.core.sympify import sympify, _sympify from sympy.matrices import (ImmutableMatrix, Inverse, Trace, Determinant, MatrixSymbol, MatrixBase, Transpose, MatrixSet, matrix2numpy) from sympy.stats.rv import (_value_check, RandomMatrixSymbol, NamedArgsMixin, PSpace, _symbol_converter, MatrixDomain, Distribution) from sympy.external import import_module ################################################################################ #------------------------Matrix Probability Space------------------------------# ################################################################################ class MatrixPSpace(PSpace): """ Represents probability space for Matrix Distributions. """ def __new__(cls, sym, distribution, dim_n, dim_m): sym = _symbol_converter(sym) dim_n, dim_m = _sympify(dim_n), _sympify(dim_m) if not (dim_n.is_integer and dim_m.is_integer): raise ValueError("Dimensions should be integers") return Basic.__new__(cls, sym, distribution, dim_n, dim_m) distribution = property(lambda self: self.args[1]) symbol = property(lambda self: self.args[0]) @property def domain(self): return MatrixDomain(self.symbol, self.distribution.set) @property def value(self): return RandomMatrixSymbol(self.symbol, self.args[2], self.args[3], self) @property def values(self): return {self.value} def compute_density(self, expr, *args): rms = expr.atoms(RandomMatrixSymbol) if len(rms) > 1 or (not isinstance(expr, RandomMatrixSymbol)): raise NotImplementedError("Currently, no algorithm has been " "implemented to handle general expressions containing " "multiple matrix distributions.") return self.distribution.pdf(expr) def sample(self, size=(), library='scipy', seed=None): """ Internal sample method Returns dictionary mapping RandomMatrixSymbol to realization value. """ return {self.value: self.distribution.sample(size, library=library, seed=seed)} def rv(symbol, cls, args): args = list(map(sympify, args)) dist = cls(*args) dist.check(*args) dim = dist.dimension pspace = MatrixPSpace(symbol, dist, dim[0], dim[1]) return pspace.value class SampleMatrixScipy: """Returns the sample from scipy of the given distribution""" def __new__(cls, dist, size, seed=None): return cls._sample_scipy(dist, size, seed) @classmethod def _sample_scipy(cls, dist, size, seed): """Sample from SciPy.""" from scipy import stats as scipy_stats import numpy scipy_rv_map = { 'WishartDistribution': lambda dist, size, rand_state: scipy_stats.wishart.rvs( df=int(dist.n), scale=matrix2numpy(dist.scale_matrix, float), size=size), 'MatrixNormalDistribution': lambda dist, size, rand_state: scipy_stats.matrix_normal.rvs( mean=matrix2numpy(dist.location_matrix, float), rowcov=matrix2numpy(dist.scale_matrix_1, float), colcov=matrix2numpy(dist.scale_matrix_2, float), size=size, random_state=rand_state) } sample_shape = { 'WishartDistribution': lambda dist: dist.scale_matrix.shape, 'MatrixNormalDistribution' : lambda dist: dist.location_matrix.shape } dist_list = scipy_rv_map.keys() if dist.__class__.__name__ not in dist_list: return None if seed is None or isinstance(seed, int): rand_state = numpy.random.default_rng(seed=seed) else: rand_state = seed samp = scipy_rv_map[dist.__class__.__name__](dist, prod(size), rand_state) return samp.reshape(size + sample_shape[dist.__class__.__name__](dist)) class SampleMatrixNumpy: """Returns the sample from numpy of the given distribution""" ### TODO: Add tests after adding matrix distributions in numpy_rv_map def __new__(cls, dist, size, seed=None): return cls._sample_numpy(dist, size, seed) @classmethod def _sample_numpy(cls, dist, size, seed): """Sample from NumPy.""" numpy_rv_map = { } sample_shape = { } dist_list = numpy_rv_map.keys() if dist.__class__.__name__ not in dist_list: return None import numpy if seed is None or isinstance(seed, int): rand_state = numpy.random.default_rng(seed=seed) else: rand_state = seed samp = numpy_rv_map[dist.__class__.__name__](dist, prod(size), rand_state) return samp.reshape(size + sample_shape[dist.__class__.__name__](dist)) class SampleMatrixPymc: """Returns the sample from pymc3 of the given distribution""" def __new__(cls, dist, size, seed=None): return cls._sample_pymc3(dist, size, seed) @classmethod def _sample_pymc3(cls, dist, size, seed): """Sample from PyMC3.""" import pymc3 pymc3_rv_map = { 'MatrixNormalDistribution': lambda dist: pymc3.MatrixNormal('X', mu=matrix2numpy(dist.location_matrix, float), rowcov=matrix2numpy(dist.scale_matrix_1, float), colcov=matrix2numpy(dist.scale_matrix_2, float), shape=dist.location_matrix.shape), 'WishartDistribution': lambda dist: pymc3.WishartBartlett('X', nu=int(dist.n), S=matrix2numpy(dist.scale_matrix, float)) } sample_shape = { 'WishartDistribution': lambda dist: dist.scale_matrix.shape, 'MatrixNormalDistribution' : lambda dist: dist.location_matrix.shape } dist_list = pymc3_rv_map.keys() if dist.__class__.__name__ not in dist_list: return None import logging logging.getLogger("pymc3").setLevel(logging.ERROR) with pymc3.Model(): pymc3_rv_map[dist.__class__.__name__](dist) samps = pymc3.sample(draws=prod(size), chains=1, progressbar=False, random_seed=seed, return_inferencedata=False, compute_convergence_checks=False)['X'] return samps.reshape(size + sample_shape[dist.__class__.__name__](dist)) _get_sample_class_matrixrv = { 'scipy': SampleMatrixScipy, 'pymc3': SampleMatrixPymc, 'numpy': SampleMatrixNumpy } ################################################################################ #-------------------------Matrix Distribution----------------------------------# ################################################################################ class MatrixDistribution(Distribution, NamedArgsMixin): """ Abstract class for Matrix Distribution. """ def __new__(cls, *args): args = list(map(sympify, args)) return Basic.__new__(cls, *args) @staticmethod def check(*args): pass def __call__(self, expr): if isinstance(expr, list): expr = ImmutableMatrix(expr) return self.pdf(expr) def sample(self, size=(), library='scipy', seed=None): """ Internal sample method Returns dictionary mapping RandomSymbol to realization value. """ libraries = ['scipy', 'numpy', 'pymc3'] if library not in libraries: raise NotImplementedError("Sampling from %s is not supported yet." % str(library)) if not import_module(library): raise ValueError("Failed to import %s" % library) samps = _get_sample_class_matrixrv[library](self, size, seed) if samps is not None: return samps raise NotImplementedError( "Sampling for %s is not currently implemented from %s" % (self.__class__.__name__, library) ) ################################################################################ #------------------------Matrix Distribution Types-----------------------------# ################################################################################ #------------------------------------------------------------------------------- # Matrix Gamma distribution ---------------------------------------------------- class MatrixGammaDistribution(MatrixDistribution): _argnames = ('alpha', 'beta', 'scale_matrix') @staticmethod def check(alpha, beta, scale_matrix): if not isinstance(scale_matrix , MatrixSymbol): _value_check(scale_matrix.is_positive_definite, "The shape " "matrix must be positive definite.") _value_check(scale_matrix.is_square, "Should " "be square matrix") _value_check(alpha.is_positive, "Shape parameter should be positive.") _value_check(beta.is_positive, "Scale parameter should be positive.") @property def set(self): k = self.scale_matrix.shape[0] return MatrixSet(k, k, S.Reals) @property def dimension(self): return self.scale_matrix.shape def pdf(self, x): alpha , beta , scale_matrix = self.alpha, self.beta, self.scale_matrix p = scale_matrix.shape[0] if isinstance(x, list): x = ImmutableMatrix(x) if not isinstance(x, (MatrixBase, MatrixSymbol)): raise ValueError("%s should be an isinstance of Matrix " "or MatrixSymbol" % str(x)) sigma_inv_x = - Inverse(scale_matrix)*x / beta term1 = exp(Trace(sigma_inv_x))/((beta**(p*alpha)) * multigamma(alpha, p)) term2 = (Determinant(scale_matrix))**(-alpha) term3 = (Determinant(x))**(alpha - S(p + 1)/2) return term1 * term2 * term3 def MatrixGamma(symbol, alpha, beta, scale_matrix): """ Creates a random variable with Matrix Gamma Distribution. The density of the said distribution can be found at [1]. Parameters ========== alpha: Positive Real number Shape Parameter beta: Positive Real number Scale Parameter scale_matrix: Positive definite real square matrix Scale Matrix Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import density, MatrixGamma >>> from sympy import MatrixSymbol, symbols >>> a, b = symbols('a b', positive=True) >>> M = MatrixGamma('M', a, b, [[2, 1], [1, 2]]) >>> X = MatrixSymbol('X', 2, 2) >>> density(M)(X).doit() exp(Trace(Matrix([ [-2/3, 1/3], [ 1/3, -2/3]])*X)/b)*Determinant(X)**(a - 3/2)/(3**a*sqrt(pi)*b**(2*a)*gamma(a)*gamma(a - 1/2)) >>> density(M)([[1, 0], [0, 1]]).doit() exp(-4/(3*b))/(3**a*sqrt(pi)*b**(2*a)*gamma(a)*gamma(a - 1/2)) References ========== .. [1] https://en.wikipedia.org/wiki/Matrix_gamma_distribution """ if isinstance(scale_matrix, list): scale_matrix = ImmutableMatrix(scale_matrix) return rv(symbol, MatrixGammaDistribution, (alpha, beta, scale_matrix)) #------------------------------------------------------------------------------- # Wishart Distribution --------------------------------------------------------- class WishartDistribution(MatrixDistribution): _argnames = ('n', 'scale_matrix') @staticmethod def check(n, scale_matrix): if not isinstance(scale_matrix , MatrixSymbol): _value_check(scale_matrix.is_positive_definite, "The shape " "matrix must be positive definite.") _value_check(scale_matrix.is_square, "Should " "be square matrix") _value_check(n.is_positive, "Shape parameter should be positive.") @property def set(self): k = self.scale_matrix.shape[0] return MatrixSet(k, k, S.Reals) @property def dimension(self): return self.scale_matrix.shape def pdf(self, x): n, scale_matrix = self.n, self.scale_matrix p = scale_matrix.shape[0] if isinstance(x, list): x = ImmutableMatrix(x) if not isinstance(x, (MatrixBase, MatrixSymbol)): raise ValueError("%s should be an isinstance of Matrix " "or MatrixSymbol" % str(x)) sigma_inv_x = - Inverse(scale_matrix)*x / S(2) term1 = exp(Trace(sigma_inv_x))/((2**(p*n/S(2))) * multigamma(n/S(2), p)) term2 = (Determinant(scale_matrix))**(-n/S(2)) term3 = (Determinant(x))**(S(n - p - 1)/2) return term1 * term2 * term3 def Wishart(symbol, n, scale_matrix): """ Creates a random variable with Wishart Distribution. The density of the said distribution can be found at [1]. Parameters ========== n: Positive Real number Represents degrees of freedom scale_matrix: Positive definite real square matrix Scale Matrix Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import density, Wishart >>> from sympy import MatrixSymbol, symbols >>> n = symbols('n', positive=True) >>> W = Wishart('W', n, [[2, 1], [1, 2]]) >>> X = MatrixSymbol('X', 2, 2) >>> density(W)(X).doit() exp(Trace(Matrix([ [-1/3, 1/6], [ 1/6, -1/3]])*X))*Determinant(X)**(n/2 - 3/2)/(2**n*3**(n/2)*sqrt(pi)*gamma(n/2)*gamma(n/2 - 1/2)) >>> density(W)([[1, 0], [0, 1]]).doit() exp(-2/3)/(2**n*3**(n/2)*sqrt(pi)*gamma(n/2)*gamma(n/2 - 1/2)) References ========== .. [1] https://en.wikipedia.org/wiki/Wishart_distribution """ if isinstance(scale_matrix, list): scale_matrix = ImmutableMatrix(scale_matrix) return rv(symbol, WishartDistribution, (n, scale_matrix)) #------------------------------------------------------------------------------- # Matrix Normal distribution --------------------------------------------------- class MatrixNormalDistribution(MatrixDistribution): _argnames = ('location_matrix', 'scale_matrix_1', 'scale_matrix_2') @staticmethod def check(location_matrix, scale_matrix_1, scale_matrix_2): if not isinstance(scale_matrix_1 , MatrixSymbol): _value_check(scale_matrix_1.is_positive_definite, "The shape " "matrix must be positive definite.") if not isinstance(scale_matrix_2 , MatrixSymbol): _value_check(scale_matrix_2.is_positive_definite, "The shape " "matrix must be positive definite.") _value_check(scale_matrix_1.is_square, "Scale matrix 1 should be " "be square matrix") _value_check(scale_matrix_2.is_square, "Scale matrix 2 should be " "be square matrix") n = location_matrix.shape[0] p = location_matrix.shape[1] _value_check(scale_matrix_1.shape[0] == n, "Scale matrix 1 should be" " of shape %s x %s"% (str(n), str(n))) _value_check(scale_matrix_2.shape[0] == p, "Scale matrix 2 should be" " of shape %s x %s"% (str(p), str(p))) @property def set(self): n, p = self.location_matrix.shape return MatrixSet(n, p, S.Reals) @property def dimension(self): return self.location_matrix.shape def pdf(self, x): M , U , V = self.location_matrix, self.scale_matrix_1, self.scale_matrix_2 n, p = M.shape if isinstance(x, list): x = ImmutableMatrix(x) if not isinstance(x, (MatrixBase, MatrixSymbol)): raise ValueError("%s should be an isinstance of Matrix " "or MatrixSymbol" % str(x)) term1 = Inverse(V)*Transpose(x - M)*Inverse(U)*(x - M) num = exp(-Trace(term1)/S(2)) den = (2*pi)**(S(n*p)/2) * Determinant(U)**S(p)/2 * Determinant(V)**S(n)/2 return num/den def MatrixNormal(symbol, location_matrix, scale_matrix_1, scale_matrix_2): """ Creates a random variable with Matrix Normal Distribution. The density of the said distribution can be found at [1]. Parameters ========== location_matrix: Real ``n x p`` matrix Represents degrees of freedom scale_matrix_1: Positive definite matrix Scale Matrix of shape ``n x n`` scale_matrix_2: Positive definite matrix Scale Matrix of shape ``p x p`` Returns ======= RandomSymbol Examples ======== >>> from sympy import MatrixSymbol >>> from sympy.stats import density, MatrixNormal >>> M = MatrixNormal('M', [[1, 2]], [1], [[1, 0], [0, 1]]) >>> X = MatrixSymbol('X', 1, 2) >>> density(M)(X).doit() 2*exp(-Trace((Matrix([ [-1], [-2]]) + X.T)*(Matrix([[-1, -2]]) + X))/2)/pi >>> density(M)([[3, 4]]).doit() 2*exp(-4)/pi References ========== .. [1] https://en.wikipedia.org/wiki/Matrix_normal_distribution """ if isinstance(location_matrix, list): location_matrix = ImmutableMatrix(location_matrix) if isinstance(scale_matrix_1, list): scale_matrix_1 = ImmutableMatrix(scale_matrix_1) if isinstance(scale_matrix_2, list): scale_matrix_2 = ImmutableMatrix(scale_matrix_2) args = (location_matrix, scale_matrix_1, scale_matrix_2) return rv(symbol, MatrixNormalDistribution, args) #------------------------------------------------------------------------------- # Matrix Student's T distribution --------------------------------------------------- class MatrixStudentTDistribution(MatrixDistribution): _argnames = ('nu', 'location_matrix', 'scale_matrix_1', 'scale_matrix_2') @staticmethod def check(nu, location_matrix, scale_matrix_1, scale_matrix_2): if not isinstance(scale_matrix_1, MatrixSymbol): _value_check(scale_matrix_1.is_positive_definite != False, "The shape " "matrix must be positive definite.") if not isinstance(scale_matrix_2, MatrixSymbol): _value_check(scale_matrix_2.is_positive_definite != False, "The shape " "matrix must be positive definite.") _value_check(scale_matrix_1.is_square != False, "Scale matrix 1 should be " "be square matrix") _value_check(scale_matrix_2.is_square != False, "Scale matrix 2 should be " "be square matrix") n = location_matrix.shape[0] p = location_matrix.shape[1] _value_check(scale_matrix_1.shape[0] == p, "Scale matrix 1 should be" " of shape %s x %s" % (str(p), str(p))) _value_check(scale_matrix_2.shape[0] == n, "Scale matrix 2 should be" " of shape %s x %s" % (str(n), str(n))) _value_check(nu.is_positive != False, "Degrees of freedom must be positive") @property def set(self): n, p = self.location_matrix.shape return MatrixSet(n, p, S.Reals) @property def dimension(self): return self.location_matrix.shape def pdf(self, x): from sympy import eye if isinstance(x, list): x = ImmutableMatrix(x) if not isinstance(x, (MatrixBase, MatrixSymbol)): raise ValueError("%s should be an isinstance of Matrix " "or MatrixSymbol" % str(x)) nu, M, Omega, Sigma = self.nu, self.location_matrix, self.scale_matrix_1, self.scale_matrix_2 n, p = M.shape K = multigamma((nu + n + p - 1)/2, p) * Determinant(Omega)**(-n/2) * Determinant(Sigma)**(-p/2) \ / ((pi)**(n*p/2) * multigamma((nu + p - 1)/2, p)) return K * (Determinant(eye(n) + Inverse(Sigma)*(x - M)*Inverse(Omega)*Transpose(x - M))) \ **(-(nu + n + p -1)/2) def MatrixStudentT(symbol, nu, location_matrix, scale_matrix_1, scale_matrix_2): """ Creates a random variable with Matrix Gamma Distribution. The density of the said distribution can be found at [1]. Parameters ========== nu: Positive Real number degrees of freedom location_matrix: Positive definite real square matrix Location Matrix of shape ``n x p`` scale_matrix_1: Positive definite real square matrix Scale Matrix of shape ``p x p`` scale_matrix_2: Positive definite real square matrix Scale Matrix of shape ``n x n`` Returns ======= RandomSymbol Examples ======== >>> from sympy import MatrixSymbol,symbols >>> from sympy.stats import density, MatrixStudentT >>> v = symbols('v',positive=True) >>> M = MatrixStudentT('M', v, [[1, 2]], [[1, 0], [0, 1]], [1]) >>> X = MatrixSymbol('X', 1, 2) >>> density(M)(X) gamma(v/2 + 1)*Determinant((Matrix([[-1, -2]]) + X)*(Matrix([ [-1], [-2]]) + X.T) + Matrix([[1]]))**(-v/2 - 1)/(pi**1.0*gamma(v/2)*Determinant(Matrix([[1]]))**1.0*Determinant(Matrix([ [1, 0], [0, 1]]))**0.5) References ========== .. [1] https://en.wikipedia.org/wiki/Matrix_t-distribution """ if isinstance(location_matrix, list): location_matrix = ImmutableMatrix(location_matrix) if isinstance(scale_matrix_1, list): scale_matrix_1 = ImmutableMatrix(scale_matrix_1) if isinstance(scale_matrix_2, list): scale_matrix_2 = ImmutableMatrix(scale_matrix_2) args = (nu, location_matrix, scale_matrix_1, scale_matrix_2) return rv(symbol, MatrixStudentTDistribution, args)
ab60e1a82385b7d37cdee6b1a1da6b8b72442e192ea55507aa80f7d0d6b1a706
from sympy import (sympify, S, pi, sqrt, exp, Lambda, Indexed, besselk, gamma, Interval, Range, factorial, Mul, Integer, Add, rf, Eq, Piecewise, ones, Symbol, Pow, Rational, Sum, Intersection, Matrix, symbols, Product, IndexedBase) from sympy.matrices import ImmutableMatrix, MatrixSymbol from sympy.matrices.expressions.determinant import det from sympy.matrices.expressions.matexpr import MatrixElement from sympy.stats.joint_rv import JointDistribution, JointPSpace, MarginalDistribution from sympy.stats.rv import _value_check, random_symbols __all__ = ['JointRV', 'MultivariateNormal', 'MultivariateLaplace', 'Dirichlet', 'GeneralizedMultivariateLogGamma', 'GeneralizedMultivariateLogGammaOmega', 'Multinomial', 'MultivariateBeta', 'MultivariateEwens', 'MultivariateT', 'NegativeMultinomial', 'NormalGamma' ] def multivariate_rv(cls, sym, *args): args = list(map(sympify, args)) dist = cls(*args) args = dist.args dist.check(*args) return JointPSpace(sym, dist).value def marginal_distribution(rv, *indices): """ Marginal distribution function of a joint random variable. Parameters ========== rv: A random variable with a joint probability distribution. indices: component indices or the indexed random symbol for whom the joint distribution is to be calculated Returns ======= A Lambda expression in `sym`. Examples ======== >>> from sympy.stats import MultivariateNormal, marginal_distribution >>> m = MultivariateNormal('X', [1, 2], [[2, 1], [1, 2]]) >>> marginal_distribution(m, m[0])(1) 1/(2*sqrt(pi)) """ indices = list(indices) for i in range(len(indices)): if isinstance(indices[i], Indexed): indices[i] = indices[i].args[1] prob_space = rv.pspace if not indices: raise ValueError( "At least one component for marginal density is needed.") if hasattr(prob_space.distribution, '_marginal_distribution'): return prob_space.distribution._marginal_distribution(indices, rv.symbol) return prob_space.marginal_distribution(*indices) class JointDistributionHandmade(JointDistribution): _argnames = ('pdf',) is_Continuous = True @property def set(self): return self.args[1] def JointRV(symbol, pdf, _set=None): """ Create a Joint Random Variable where each of its component is conitinuous, given the following: -- a symbol -- a PDF in terms of indexed symbols of the symbol given as the first argument NOTE: As of now, the set for each component for a `JointRV` is equal to the set of all integers, which can not be changed. Examples ======== >>> from sympy import exp, pi, Indexed, S >>> from sympy.stats import density, JointRV >>> x1, x2 = (Indexed('x', i) for i in (1, 2)) >>> pdf = exp(-x1**2/2 + x1 - x2**2/2 - S(1)/2)/(2*pi) >>> N1 = JointRV('x', pdf) #Multivariate Normal distribution >>> density(N1)(1, 2) exp(-2)/(2*pi) Returns ======= RandomSymbol """ #TODO: Add support for sets provided by the user symbol = sympify(symbol) syms = list(i for i in pdf.free_symbols if isinstance(i, Indexed) and i.base == IndexedBase(symbol)) syms = tuple(sorted(syms, key = lambda index: index.args[1])) _set = S.Reals**len(syms) pdf = Lambda(syms, pdf) dist = JointDistributionHandmade(pdf, _set) jrv = JointPSpace(symbol, dist).value rvs = random_symbols(pdf) if len(rvs) != 0: dist = MarginalDistribution(dist, (jrv,)) return JointPSpace(symbol, dist).value return jrv #------------------------------------------------------------------------------- # Multivariate Normal distribution --------------------------------------------- class MultivariateNormalDistribution(JointDistribution): _argnames = ('mu', 'sigma') is_Continuous=True @property def set(self): k = self.mu.shape[0] return S.Reals**k @staticmethod def check(mu, sigma): _value_check(mu.shape[0] == sigma.shape[0], "Size of the mean vector and covariance matrix are incorrect.") #check if covariance matrix is positive definite or not. if not isinstance(sigma, MatrixSymbol): _value_check(sigma.is_positive_definite, "The covariance matrix must be positive definite. ") def pdf(self, *args): mu, sigma = self.mu, self.sigma k = mu.shape[0] if len(args) == 1 and args[0].is_Matrix: args = args[0] else: args = ImmutableMatrix(args) x = args - mu density = S.One/sqrt((2*pi)**(k)*det(sigma))*exp( Rational(-1, 2)*x.transpose()*(sigma.inv()*x)) return MatrixElement(density, 0, 0) def _marginal_distribution(self, indices, sym): sym = ImmutableMatrix([Indexed(sym, i) for i in indices]) _mu, _sigma = self.mu, self.sigma k = self.mu.shape[0] for i in range(k): if i not in indices: _mu = _mu.row_del(i) _sigma = _sigma.col_del(i) _sigma = _sigma.row_del(i) return Lambda(tuple(sym), S.One/sqrt((2*pi)**(len(_mu))*det(_sigma))*exp( Rational(-1, 2)*(_mu - sym).transpose()*(_sigma.inv()*\ (_mu - sym)))[0]) def MultivariateNormal(name, mu, sigma): """ Creates a continuous random variable with Multivariate Normal Distribution. The density of the multivariate normal distribution can be found at [1]. Parameters ========== mu : List representing the mean or the mean vector sigma : Positive definite square matrix Represents covariance Matrix Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import MultivariateNormal, density, marginal_distribution >>> from sympy import symbols, MatrixSymbol >>> X = MultivariateNormal('X', [3, 4], [[2, 1], [1, 2]]) >>> y, z = symbols('y z') >>> density(X)(y, z) sqrt(3)*exp(-y**2/3 + y*z/3 + 2*y/3 - z**2/3 + 5*z/3 - 13/3)/(6*pi) >>> density(X)(1, 2) sqrt(3)*exp(-4/3)/(6*pi) >>> marginal_distribution(X, X[1])(y) exp(-(y - 4)**2/4)/(2*sqrt(pi)) >>> marginal_distribution(X, X[0])(y) exp(-(y - 3)**2/4)/(2*sqrt(pi)) The example below shows that it is also possible to use symbolic parameters to define the MultivariateNormal class. >>> n = symbols('n', natural=True) >>> Sg = MatrixSymbol('Sg', n, n) >>> mu = MatrixSymbol('mu', n, 1) >>> obs = MatrixSymbol('obs', n, 1) >>> X = MultivariateNormal('X', mu, Sg) The density of a multivariate normal can be calculated using a matrix argument, as shown below. >>> density(X)(obs) (exp(((1/2)*mu.T - (1/2)*obs.T)*Sg**(-1)*(-mu + obs))/sqrt((2*pi)**n*Determinant(Sg)))[0, 0] References ========== .. [1] https://en.wikipedia.org/wiki/Multivariate_normal_distribution """ return multivariate_rv(MultivariateNormalDistribution, name, mu, sigma) #------------------------------------------------------------------------------- # Multivariate Laplace distribution -------------------------------------------- class MultivariateLaplaceDistribution(JointDistribution): _argnames = ('mu', 'sigma') is_Continuous=True @property def set(self): k = self.mu.shape[0] return S.Reals**k @staticmethod def check(mu, sigma): _value_check(mu.shape[0] == sigma.shape[0], "Size of the mean vector and covariance matrix are incorrect.") # check if covariance matrix is positive definite or not. if not isinstance(sigma, MatrixSymbol): _value_check(sigma.is_positive_definite, "The covariance matrix must be positive definite. ") def pdf(self, *args): mu, sigma = self.mu, self.sigma mu_T = mu.transpose() k = S(mu.shape[0]) sigma_inv = sigma.inv() args = ImmutableMatrix(args) args_T = args.transpose() x = (mu_T*sigma_inv*mu)[0] y = (args_T*sigma_inv*args)[0] v = 1 - k/2 return S(2)/((2*pi)**(S(k)/2)*sqrt(det(sigma)))\ *(y/(2 + x))**(S(v)/2)*besselk(v, sqrt((2 + x)*(y)))\ *exp((args_T*sigma_inv*mu)[0]) def MultivariateLaplace(name, mu, sigma): """ Creates a continuous random variable with Multivariate Laplace Distribution. The density of the multivariate Laplace distribution can be found at [1]. Parameters ========== mu : List representing the mean or the mean vector sigma : Positive definite square matrix Represents covariance Matrix Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import MultivariateLaplace, density >>> from sympy import symbols >>> y, z = symbols('y z') >>> X = MultivariateLaplace('X', [2, 4], [[3, 1], [1, 3]]) >>> density(X)(y, z) sqrt(2)*exp(y/4 + 5*z/4)*besselk(0, sqrt(15*y*(3*y/8 - z/8)/2 + 15*z*(-y/8 + 3*z/8)/2))/(4*pi) >>> density(X)(1, 2) sqrt(2)*exp(11/4)*besselk(0, sqrt(165)/4)/(4*pi) References ========== .. [1] https://en.wikipedia.org/wiki/Multivariate_Laplace_distribution """ return multivariate_rv(MultivariateLaplaceDistribution, name, mu, sigma) #------------------------------------------------------------------------------- # Multivariate StudentT distribution ------------------------------------------- class MultivariateTDistribution(JointDistribution): _argnames = ('mu', 'shape_mat', 'dof') is_Continuous=True @property def set(self): k = self.mu.shape[0] return S.Reals**k @staticmethod def check(mu, sigma, v): _value_check(mu.shape[0] == sigma.shape[0], "Size of the location vector and shape matrix are incorrect.") # check if covariance matrix is positive definite or not. if not isinstance(sigma, MatrixSymbol): _value_check(sigma.is_positive_definite, "The shape matrix must be positive definite. ") def pdf(self, *args): mu, sigma = self.mu, self.shape_mat v = S(self.dof) k = S(mu.shape[0]) sigma_inv = sigma.inv() args = ImmutableMatrix(args) x = args - mu return gamma((k + v)/2)/(gamma(v/2)*(v*pi)**(k/2)*sqrt(det(sigma)))\ *(1 + 1/v*(x.transpose()*sigma_inv*x)[0])**((-v - k)/2) def MultivariateT(syms, mu, sigma, v): """ Creates a joint random variable with multivariate T-distribution. Parameters ========== syms: A symbol/str For identifying the random variable. mu: A list/matrix Representing the location vector sigma: The shape matrix for the distribution Examples ======== >>> from sympy.stats import density, MultivariateT >>> from sympy import Symbol >>> x = Symbol("x") >>> X = MultivariateT("x", [1, 1], [[1, 0], [0, 1]], 2) >>> density(X)(1, 2) 2/(9*pi) Returns ======= RandomSymbol """ return multivariate_rv(MultivariateTDistribution, syms, mu, sigma, v) #------------------------------------------------------------------------------- # Multivariate Normal Gamma distribution --------------------------------------- class NormalGammaDistribution(JointDistribution): _argnames = ('mu', 'lamda', 'alpha', 'beta') is_Continuous=True @staticmethod def check(mu, lamda, alpha, beta): _value_check(mu.is_real, "Location must be real.") _value_check(lamda > 0, "Lambda must be positive") _value_check(alpha > 0, "alpha must be positive") _value_check(beta > 0, "beta must be positive") @property def set(self): return S.Reals*Interval(0, S.Infinity) def pdf(self, x, tau): beta, alpha, lamda = self.beta, self.alpha, self.lamda mu = self.mu return beta**alpha*sqrt(lamda)/(gamma(alpha)*sqrt(2*pi))*\ tau**(alpha - S.Half)*exp(-1*beta*tau)*\ exp(-1*(lamda*tau*(x - mu)**2)/S(2)) def _marginal_distribution(self, indices, *sym): if len(indices) == 2: return self.pdf(*sym) if indices[0] == 0: #For marginal over `x`, return non-standardized Student-T's #distribution x = sym[0] v, mu, sigma = self.alpha - S.Half, self.mu, \ S(self.beta)/(self.lamda * self.alpha) return Lambda(sym, gamma((v + 1)/2)/(gamma(v/2)*sqrt(pi*v)*sigma)*\ (1 + 1/v*((x - mu)/sigma)**2)**((-v -1)/2)) #For marginal over `tau`, return Gamma distribution as per construction from sympy.stats.crv_types import GammaDistribution return Lambda(sym, GammaDistribution(self.alpha, self.beta)(sym[0])) def NormalGamma(sym, mu, lamda, alpha, beta): """ Creates a bivariate joint random variable with multivariate Normal gamma distribution. Parameters ========== sym: A symbol/str For identifying the random variable. mu: A real number The mean of the normal distribution lamda: A positive integer Parameter of joint distribution alpha: A positive integer Parameter of joint distribution beta: A positive integer Parameter of joint distribution Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import density, NormalGamma >>> from sympy import symbols >>> X = NormalGamma('x', 0, 1, 2, 3) >>> y, z = symbols('y z') >>> density(X)(y, z) 9*sqrt(2)*z**(3/2)*exp(-3*z)*exp(-y**2*z/2)/(2*sqrt(pi)) References ========== .. [1] https://en.wikipedia.org/wiki/Normal-gamma_distribution """ return multivariate_rv(NormalGammaDistribution, sym, mu, lamda, alpha, beta) #------------------------------------------------------------------------------- # Multivariate Beta/Dirichlet distribution ------------------------------------- class MultivariateBetaDistribution(JointDistribution): _argnames = ('alpha',) is_Continuous = True @staticmethod def check(alpha): _value_check(len(alpha) >= 2, "At least two categories should be passed.") for a_k in alpha: _value_check((a_k > 0) != False, "Each concentration parameter" " should be positive.") @property def set(self): k = len(self.alpha) return Interval(0, 1)**k def pdf(self, *syms): alpha = self.alpha B = Mul.fromiter(map(gamma, alpha))/gamma(Add(*alpha)) return Mul.fromiter(sym**(a_k - 1) for a_k, sym in zip(alpha, syms))/B def MultivariateBeta(syms, *alpha): """ Creates a continuous random variable with Dirichlet/Multivariate Beta Distribution. The density of the dirichlet distribution can be found at [1]. Parameters ========== alpha: Positive real numbers Signifies concentration numbers. Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import density, MultivariateBeta, marginal_distribution >>> from sympy import Symbol >>> a1 = Symbol('a1', positive=True) >>> a2 = Symbol('a2', positive=True) >>> B = MultivariateBeta('B', [a1, a2]) >>> C = MultivariateBeta('C', a1, a2) >>> x = Symbol('x') >>> y = Symbol('y') >>> density(B)(x, y) x**(a1 - 1)*y**(a2 - 1)*gamma(a1 + a2)/(gamma(a1)*gamma(a2)) >>> marginal_distribution(C, C[0])(x) x**(a1 - 1)*gamma(a1 + a2)/(a2*gamma(a1)*gamma(a2)) References ========== .. [1] https://en.wikipedia.org/wiki/Dirichlet_distribution .. [2] http://mathworld.wolfram.com/DirichletDistribution.html """ if not isinstance(alpha[0], list): alpha = (list(alpha),) return multivariate_rv(MultivariateBetaDistribution, syms, alpha[0]) Dirichlet = MultivariateBeta #------------------------------------------------------------------------------- # Multivariate Ewens distribution ---------------------------------------------- class MultivariateEwensDistribution(JointDistribution): _argnames = ('n', 'theta') is_Discrete = True is_Continuous = False @staticmethod def check(n, theta): _value_check((n > 0), "sample size should be positive integer.") _value_check(theta.is_positive, "mutation rate should be positive.") @property def set(self): if not isinstance(self.n, Integer): i = Symbol('i', integer=True, positive=True) return Product(Intersection(S.Naturals0, Interval(0, self.n//i)), (i, 1, self.n)) prod_set = Range(0, self.n + 1) for i in range(2, self.n + 1): prod_set *= Range(0, self.n//i + 1) return prod_set.flatten() def pdf(self, *syms): n, theta = self.n, self.theta condi = isinstance(self.n, Integer) if not (isinstance(syms[0], IndexedBase) or condi): raise ValueError("Please use IndexedBase object for syms as " "the dimension is symbolic") term_1 = factorial(n)/rf(theta, n) if condi: term_2 = Mul.fromiter(theta**syms[j]/((j+1)**syms[j]*factorial(syms[j])) for j in range(n)) cond = Eq(sum([(k + 1)*syms[k] for k in range(n)]), n) return Piecewise((term_1 * term_2, cond), (0, True)) syms = syms[0] j, k = symbols('j, k', positive=True, integer=True) term_2 = Product(theta**syms[j]/((j+1)**syms[j]*factorial(syms[j])), (j, 0, n - 1)) cond = Eq(Sum((k + 1)*syms[k], (k, 0, n - 1)), n) return Piecewise((term_1 * term_2, cond), (0, True)) def MultivariateEwens(syms, n, theta): """ Creates a discrete random variable with Multivariate Ewens Distribution. The density of the said distribution can be found at [1]. Parameters ========== n: Positive integer Size of the sample or the integer whose partitions are considered theta: Positive real number Denotes Mutation rate Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import density, marginal_distribution, MultivariateEwens >>> from sympy import Symbol >>> a1 = Symbol('a1', positive=True) >>> a2 = Symbol('a2', positive=True) >>> ed = MultivariateEwens('E', 2, 1) >>> density(ed)(a1, a2) Piecewise((1/(2**a2*factorial(a1)*factorial(a2)), Eq(a1 + 2*a2, 2)), (0, True)) >>> marginal_distribution(ed, ed[0])(a1) Piecewise((1/factorial(a1), Eq(a1, 2)), (0, True)) References ========== .. [1] https://en.wikipedia.org/wiki/Ewens%27s_sampling_formula .. [2] http://www.stat.rutgers.edu/home/hcrane/Papers/STS529.pdf """ return multivariate_rv(MultivariateEwensDistribution, syms, n, theta) #------------------------------------------------------------------------------- # Generalized Multivariate Log Gamma distribution ------------------------------ class GeneralizedMultivariateLogGammaDistribution(JointDistribution): _argnames = ('delta', 'v', 'lamda', 'mu') is_Continuous=True def check(self, delta, v, l, mu): _value_check((delta >= 0, delta <= 1), "delta must be in range [0, 1].") _value_check((v > 0), "v must be positive") for lk in l: _value_check((lk > 0), "lamda must be a positive vector.") for muk in mu: _value_check((muk > 0), "mu must be a positive vector.") _value_check(len(l) > 1,"the distribution should have at least" " two random variables.") @property def set(self): return S.Reals**len(self.lamda) def pdf(self, *y): from sympy.functions.special.gamma_functions import gamma d, v, l, mu = self.delta, self.v, self.lamda, self.mu n = Symbol('n', negative=False, integer=True) k = len(l) sterm1 = Pow((1 - d), n)/\ ((gamma(v + n)**(k - 1))*gamma(v)*gamma(n + 1)) sterm2 = Mul.fromiter(mui*li**(-v - n) for mui, li in zip(mu, l)) term1 = sterm1 * sterm2 sterm3 = (v + n) * sum([mui * yi for mui, yi in zip(mu, y)]) sterm4 = sum([exp(mui * yi)/li for (mui, yi, li) in zip(mu, y, l)]) term2 = exp(sterm3 - sterm4) return Pow(d, v) * Sum(term1 * term2, (n, 0, S.Infinity)) def GeneralizedMultivariateLogGamma(syms, delta, v, lamda, mu): """ Creates a joint random variable with generalized multivariate log gamma distribution. The joint pdf can be found at [1]. Parameters ========== syms: list/tuple/set of symbols for identifying each component delta: A constant in range [0, 1] v: Positive real number lamda: List of positive real numbers mu: List of positive real numbers Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import density >>> from sympy.stats.joint_rv_types import GeneralizedMultivariateLogGamma >>> from sympy import symbols, S >>> v = 1 >>> l, mu = [1, 1, 1], [1, 1, 1] >>> d = S.Half >>> y = symbols('y_1:4', positive=True) >>> Gd = GeneralizedMultivariateLogGamma('G', d, v, l, mu) >>> density(Gd)(y[0], y[1], y[2]) Sum(exp((n + 1)*(y_1 + y_2 + y_3) - exp(y_1) - exp(y_2) - exp(y_3))/(2**n*gamma(n + 1)**3), (n, 0, oo))/2 References ========== .. [1] https://en.wikipedia.org/wiki/Generalized_multivariate_log-gamma_distribution .. [2] https://www.researchgate.net/publication/234137346_On_a_multivariate_log-gamma_distribution_and_the_use_of_the_distribution_in_the_Bayesian_analysis Note ==== If the GeneralizedMultivariateLogGamma is too long to type use, `from sympy.stats.joint_rv_types import GeneralizedMultivariateLogGamma as GMVLG` If you want to pass the matrix omega instead of the constant delta, then use, GeneralizedMultivariateLogGammaOmega. """ return multivariate_rv(GeneralizedMultivariateLogGammaDistribution, syms, delta, v, lamda, mu) def GeneralizedMultivariateLogGammaOmega(syms, omega, v, lamda, mu): """ Extends GeneralizedMultivariateLogGamma. Parameters ========== syms: list/tuple/set of symbols For identifying each component omega: A square matrix Every element of square matrix must be absolute value of square root of correlation coefficient v: Positive real number lamda: List of positive real numbers mu: List of positive real numbers Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import density >>> from sympy.stats.joint_rv_types import GeneralizedMultivariateLogGammaOmega >>> from sympy import Matrix, symbols, S >>> omega = Matrix([[1, S.Half, S.Half], [S.Half, 1, S.Half], [S.Half, S.Half, 1]]) >>> v = 1 >>> l, mu = [1, 1, 1], [1, 1, 1] >>> G = GeneralizedMultivariateLogGammaOmega('G', omega, v, l, mu) >>> y = symbols('y_1:4', positive=True) >>> density(G)(y[0], y[1], y[2]) sqrt(2)*Sum((1 - sqrt(2)/2)**n*exp((n + 1)*(y_1 + y_2 + y_3) - exp(y_1) - exp(y_2) - exp(y_3))/gamma(n + 1)**3, (n, 0, oo))/2 References ========== .. [1] https://en.wikipedia.org/wiki/Generalized_multivariate_log-gamma_distribution .. [2] https://www.researchgate.net/publication/234137346_On_a_multivariate_log-gamma_distribution_and_the_use_of_the_distribution_in_the_Bayesian_analysis Notes ===== If the GeneralizedMultivariateLogGammaOmega is too long to type use, `from sympy.stats.joint_rv_types import GeneralizedMultivariateLogGammaOmega as GMVLGO` """ _value_check((omega.is_square, isinstance(omega, Matrix)), "omega must be a" " square matrix") for val in omega.values(): _value_check((val >= 0, val <= 1), "all values in matrix must be between 0 and 1(both inclusive).") _value_check(omega.diagonal().equals(ones(1, omega.shape[0])), "all the elements of diagonal should be 1.") _value_check((omega.shape[0] == len(lamda), len(lamda) == len(mu)), "lamda, mu should be of same length and omega should " " be of shape (length of lamda, length of mu)") _value_check(len(lamda) > 1,"the distribution should have at least" " two random variables.") delta = Pow(Rational(omega.det()), Rational(1, len(lamda) - 1)) return GeneralizedMultivariateLogGamma(syms, delta, v, lamda, mu) #------------------------------------------------------------------------------- # Multinomial distribution ----------------------------------------------------- class MultinomialDistribution(JointDistribution): _argnames = ('n', 'p') is_Continuous=False is_Discrete = True @staticmethod def check(n, p): _value_check(n > 0, "number of trials must be a positive integer") for p_k in p: _value_check((p_k >= 0, p_k <= 1), "probability must be in range [0, 1]") _value_check(Eq(sum(p), 1), "probabilities must sum to 1") @property def set(self): return Intersection(S.Naturals0, Interval(0, self.n))**len(self.p) def pdf(self, *x): n, p = self.n, self.p term_1 = factorial(n)/Mul.fromiter(factorial(x_k) for x_k in x) term_2 = Mul.fromiter(p_k**x_k for p_k, x_k in zip(p, x)) return Piecewise((term_1 * term_2, Eq(sum(x), n)), (0, True)) def Multinomial(syms, n, *p): """ Creates a discrete random variable with Multinomial Distribution. The density of the said distribution can be found at [1]. Parameters ========== n: Positive integer Represents number of trials p: List of event probabilites Must be in the range of [0, 1] Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import density, Multinomial, marginal_distribution >>> from sympy import symbols >>> x1, x2, x3 = symbols('x1, x2, x3', nonnegative=True, integer=True) >>> p1, p2, p3 = symbols('p1, p2, p3', positive=True) >>> M = Multinomial('M', 3, p1, p2, p3) >>> density(M)(x1, x2, x3) Piecewise((6*p1**x1*p2**x2*p3**x3/(factorial(x1)*factorial(x2)*factorial(x3)), Eq(x1 + x2 + x3, 3)), (0, True)) >>> marginal_distribution(M, M[0])(x1).subs(x1, 1) 3*p1*p2**2 + 6*p1*p2*p3 + 3*p1*p3**2 References ========== .. [1] https://en.wikipedia.org/wiki/Multinomial_distribution .. [2] http://mathworld.wolfram.com/MultinomialDistribution.html """ if not isinstance(p[0], list): p = (list(p), ) return multivariate_rv(MultinomialDistribution, syms, n, p[0]) #------------------------------------------------------------------------------- # Negative Multinomial Distribution -------------------------------------------- class NegativeMultinomialDistribution(JointDistribution): _argnames = ('k0', 'p') is_Continuous=False is_Discrete = True @staticmethod def check(k0, p): _value_check(k0 > 0, "number of failures must be a positive integer") for p_k in p: _value_check((p_k >= 0, p_k <= 1), "probability must be in range [0, 1].") _value_check(sum(p) <= 1, "success probabilities must not be greater than 1.") @property def set(self): return Range(0, S.Infinity)**len(self.p) def pdf(self, *k): k0, p = self.k0, self.p term_1 = (gamma(k0 + sum(k))*(1 - sum(p))**k0)/gamma(k0) term_2 = Mul.fromiter(pi**ki/factorial(ki) for pi, ki in zip(p, k)) return term_1 * term_2 def NegativeMultinomial(syms, k0, *p): """ Creates a discrete random variable with Negative Multinomial Distribution. The density of the said distribution can be found at [1]. Parameters ========== k0: positive integer Represents number of failures before the experiment is stopped p: List of event probabilites Must be in the range of [0, 1] Returns ======= RandomSymbol Examples ======== >>> from sympy.stats import density, NegativeMultinomial, marginal_distribution >>> from sympy import symbols >>> x1, x2, x3 = symbols('x1, x2, x3', nonnegative=True, integer=True) >>> p1, p2, p3 = symbols('p1, p2, p3', positive=True) >>> N = NegativeMultinomial('M', 3, p1, p2, p3) >>> N_c = NegativeMultinomial('M', 3, 0.1, 0.1, 0.1) >>> density(N)(x1, x2, x3) p1**x1*p2**x2*p3**x3*(-p1 - p2 - p3 + 1)**3*gamma(x1 + x2 + x3 + 3)/(2*factorial(x1)*factorial(x2)*factorial(x3)) >>> marginal_distribution(N_c, N_c[0])(1).evalf().round(2) 0.25 References ========== .. [1] https://en.wikipedia.org/wiki/Negative_multinomial_distribution .. [2] http://mathworld.wolfram.com/NegativeBinomialDistribution.html """ if not isinstance(p[0], list): p = (list(p), ) return multivariate_rv(NegativeMultinomialDistribution, syms, k0, p[0])
75063081da48fdf8d9e30bd59f5001082e8b9c0e743ce153916095c89ff4882b
""" Main Random Variables Module Defines abstract random variable type. Contains interfaces for probability space object (PSpace) as well as standard operators, P, E, sample, density, where, quantile See Also ======== sympy.stats.crv sympy.stats.frv sympy.stats.rv_interface """ from functools import singledispatch from typing import Tuple as tTuple from sympy import (Basic, S, Expr, Symbol, Tuple, And, Add, Eq, lambdify, Or, Equality, Lambda, sympify, Dummy, Ne, KroneckerDelta, DiracDelta, Mul, Indexed, MatrixSymbol, Function, prod) from sympy.core.relational import Relational from sympy.core.sympify import _sympify from sympy.sets.sets import FiniteSet, ProductSet, Intersection from sympy.solvers.solveset import solveset from sympy.external import import_module from sympy.utilities.misc import filldedent from sympy.utilities.decorator import doctest_depends_on from sympy.utilities.exceptions import SymPyDeprecationWarning import warnings x = Symbol('x') @singledispatch def is_random(x): return False @is_random.register(Basic) def _(x): atoms = x.free_symbols return any([is_random(i) for i in atoms]) class RandomDomain(Basic): """ Represents a set of variables and the values which they can take. See Also ======== sympy.stats.crv.ContinuousDomain sympy.stats.frv.FiniteDomain """ is_ProductDomain = False is_Finite = False is_Continuous = False is_Discrete = False def __new__(cls, symbols, *args): symbols = FiniteSet(*symbols) return Basic.__new__(cls, symbols, *args) @property def symbols(self): return self.args[0] @property def set(self): return self.args[1] def __contains__(self, other): raise NotImplementedError() def compute_expectation(self, expr): raise NotImplementedError() class SingleDomain(RandomDomain): """ A single variable and its domain. See Also ======== sympy.stats.crv.SingleContinuousDomain sympy.stats.frv.SingleFiniteDomain """ def __new__(cls, symbol, set): assert symbol.is_Symbol return Basic.__new__(cls, symbol, set) @property def symbol(self): return self.args[0] @property def symbols(self): return FiniteSet(self.symbol) def __contains__(self, other): if len(other) != 1: return False sym, val = tuple(other)[0] return self.symbol == sym and val in self.set class MatrixDomain(RandomDomain): """ A Random Matrix variable and its domain. """ def __new__(cls, symbol, set): symbol, set = _symbol_converter(symbol), _sympify(set) return Basic.__new__(cls, symbol, set) @property def symbol(self): return self.args[0] @property def symbols(self): return FiniteSet(self.symbol) class ConditionalDomain(RandomDomain): """ A RandomDomain with an attached condition. See Also ======== sympy.stats.crv.ConditionalContinuousDomain sympy.stats.frv.ConditionalFiniteDomain """ def __new__(cls, fulldomain, condition): condition = condition.xreplace({rs: rs.symbol for rs in random_symbols(condition)}) return Basic.__new__(cls, fulldomain, condition) @property def symbols(self): return self.fulldomain.symbols @property def fulldomain(self): return self.args[0] @property def condition(self): return self.args[1] @property def set(self): raise NotImplementedError("Set of Conditional Domain not Implemented") def as_boolean(self): return And(self.fulldomain.as_boolean(), self.condition) class PSpace(Basic): """ A Probability Space. Explanation =========== Probability Spaces encode processes that equal different values probabilistically. These underly Random Symbols which occur in SymPy expressions and contain the mechanics to evaluate statistical statements. See Also ======== sympy.stats.crv.ContinuousPSpace sympy.stats.frv.FinitePSpace """ is_Finite = None # type: bool is_Continuous = None # type: bool is_Discrete = None # type: bool is_real = None # type: bool @property def domain(self): return self.args[0] @property def density(self): return self.args[1] @property def values(self): return frozenset(RandomSymbol(sym, self) for sym in self.symbols) @property def symbols(self): return self.domain.symbols def where(self, condition): raise NotImplementedError() def compute_density(self, expr): raise NotImplementedError() def sample(self, size=(), library='scipy', seed=None): raise NotImplementedError() def probability(self, condition): raise NotImplementedError() def compute_expectation(self, expr): raise NotImplementedError() class SinglePSpace(PSpace): """ Represents the probabilities of a set of random events that can be attributed to a single variable/symbol. """ def __new__(cls, s, distribution): s = _symbol_converter(s) return Basic.__new__(cls, s, distribution) @property def value(self): return RandomSymbol(self.symbol, self) @property def symbol(self): return self.args[0] @property def distribution(self): return self.args[1] @property def pdf(self): return self.distribution.pdf(self.symbol) class RandomSymbol(Expr): """ Random Symbols represent ProbabilitySpaces in SymPy Expressions. In principle they can take on any value that their symbol can take on within the associated PSpace with probability determined by the PSpace Density. Explanation =========== Random Symbols contain pspace and symbol properties. The pspace property points to the represented Probability Space The symbol is a standard SymPy Symbol that is used in that probability space for example in defining a density. You can form normal SymPy expressions using RandomSymbols and operate on those expressions with the Functions E - Expectation of a random expression P - Probability of a condition density - Probability Density of an expression given - A new random expression (with new random symbols) given a condition An object of the RandomSymbol type should almost never be created by the user. They tend to be created instead by the PSpace class's value method. Traditionally a user doesn't even do this but instead calls one of the convenience functions Normal, Exponential, Coin, Die, FiniteRV, etc.... """ def __new__(cls, symbol, pspace=None): from sympy.stats.joint_rv import JointRandomSymbol if pspace is None: # Allow single arg, representing pspace == PSpace() pspace = PSpace() symbol = _symbol_converter(symbol) if not isinstance(pspace, PSpace): raise TypeError("pspace variable should be of type PSpace") if cls == JointRandomSymbol and isinstance(pspace, SinglePSpace): cls = RandomSymbol return Basic.__new__(cls, symbol, pspace) is_finite = True is_symbol = True is_Atom = True _diff_wrt = True pspace = property(lambda self: self.args[1]) symbol = property(lambda self: self.args[0]) name = property(lambda self: self.symbol.name) def _eval_is_positive(self): return self.symbol.is_positive def _eval_is_integer(self): return self.symbol.is_integer def _eval_is_real(self): return self.symbol.is_real or self.pspace.is_real @property def is_commutative(self): return self.symbol.is_commutative @property def free_symbols(self): return {self} class RandomIndexedSymbol(RandomSymbol): def __new__(cls, idx_obj, pspace=None): if pspace is None: # Allow single arg, representing pspace == PSpace() pspace = PSpace() if not isinstance(idx_obj, (Indexed, Function)): raise TypeError("An Function or Indexed object is expected not %s"%(idx_obj)) return Basic.__new__(cls, idx_obj, pspace) symbol = property(lambda self: self.args[0]) name = property(lambda self: str(self.args[0])) @property def key(self): if isinstance(self.symbol, Indexed): return self.symbol.args[1] elif isinstance(self.symbol, Function): return self.symbol.args[0] @property def free_symbols(self): if self.key.free_symbols: free_syms = self.key.free_symbols free_syms.add(self) return free_syms return {self} @property def pspace(self): return self.args[1] class RandomMatrixSymbol(RandomSymbol, MatrixSymbol): # type: ignore def __new__(cls, symbol, n, m, pspace=None): n, m = _sympify(n), _sympify(m) symbol = _symbol_converter(symbol) if pspace is None: # Allow single arg, representing pspace == PSpace() pspace = PSpace() return Basic.__new__(cls, symbol, n, m, pspace) symbol = property(lambda self: self.args[0]) pspace = property(lambda self: self.args[3]) class ProductPSpace(PSpace): """ Abstract class for representing probability spaces with multiple random variables. See Also ======== sympy.stats.rv.IndependentProductPSpace sympy.stats.joint_rv.JointPSpace """ pass class IndependentProductPSpace(ProductPSpace): """ A probability space resulting from the merger of two independent probability spaces. Often created using the function, pspace. """ def __new__(cls, *spaces): rs_space_dict = {} for space in spaces: for value in space.values: rs_space_dict[value] = space symbols = FiniteSet(*[val.symbol for val in rs_space_dict.keys()]) # Overlapping symbols from sympy.stats.joint_rv import MarginalDistribution from sympy.stats.compound_rv import CompoundDistribution if len(symbols) < sum(len(space.symbols) for space in spaces if not isinstance(space.distribution, ( CompoundDistribution, MarginalDistribution))): raise ValueError("Overlapping Random Variables") if all(space.is_Finite for space in spaces): from sympy.stats.frv import ProductFinitePSpace cls = ProductFinitePSpace obj = Basic.__new__(cls, *FiniteSet(*spaces)) return obj @property def pdf(self): p = Mul(*[space.pdf for space in self.spaces]) return p.subs({rv: rv.symbol for rv in self.values}) @property def rs_space_dict(self): d = {} for space in self.spaces: for value in space.values: d[value] = space return d @property def symbols(self): return FiniteSet(*[val.symbol for val in self.rs_space_dict.keys()]) @property def spaces(self): return FiniteSet(*self.args) @property def values(self): return sumsets(space.values for space in self.spaces) def compute_expectation(self, expr, rvs=None, evaluate=False, **kwargs): rvs = rvs or self.values rvs = frozenset(rvs) for space in self.spaces: expr = space.compute_expectation(expr, rvs & space.values, evaluate=False, **kwargs) if evaluate and hasattr(expr, 'doit'): return expr.doit(**kwargs) return expr @property def domain(self): return ProductDomain(*[space.domain for space in self.spaces]) @property def density(self): raise NotImplementedError("Density not available for ProductSpaces") def sample(self, size=(), library='scipy', seed=None): return {k: v for space in self.spaces for k, v in space.sample(size=size, library=library, seed=seed).items()} def probability(self, condition, **kwargs): cond_inv = False if isinstance(condition, Ne): condition = Eq(condition.args[0], condition.args[1]) cond_inv = True elif isinstance(condition, And): # they are independent return Mul(*[self.probability(arg) for arg in condition.args]) elif isinstance(condition, Or): # they are independent return Add(*[self.probability(arg) for arg in condition.args]) expr = condition.lhs - condition.rhs rvs = random_symbols(expr) dens = self.compute_density(expr) if any([pspace(rv).is_Continuous for rv in rvs]): from sympy.stats.crv import SingleContinuousPSpace from sympy.stats.crv_types import ContinuousDistributionHandmade if expr in self.values: # Marginalize all other random symbols out of the density randomsymbols = tuple(set(self.values) - frozenset([expr])) symbols = tuple(rs.symbol for rs in randomsymbols) pdf = self.domain.integrate(self.pdf, symbols, **kwargs) return Lambda(expr.symbol, pdf) dens = ContinuousDistributionHandmade(dens) z = Dummy('z', real=True) space = SingleContinuousPSpace(z, dens) result = space.probability(condition.__class__(space.value, 0)) else: from sympy.stats.drv import SingleDiscretePSpace from sympy.stats.drv_types import DiscreteDistributionHandmade dens = DiscreteDistributionHandmade(dens) z = Dummy('z', integer=True) space = SingleDiscretePSpace(z, dens) result = space.probability(condition.__class__(space.value, 0)) return result if not cond_inv else S.One - result def compute_density(self, expr, **kwargs): rvs = random_symbols(expr) if any(pspace(rv).is_Continuous for rv in rvs): z = Dummy('z', real=True) expr = self.compute_expectation(DiracDelta(expr - z), **kwargs) else: z = Dummy('z', integer=True) expr = self.compute_expectation(KroneckerDelta(expr, z), **kwargs) return Lambda(z, expr) def compute_cdf(self, expr, **kwargs): raise ValueError("CDF not well defined on multivariate expressions") def conditional_space(self, condition, normalize=True, **kwargs): rvs = random_symbols(condition) condition = condition.xreplace({rv: rv.symbol for rv in self.values}) if any([pspace(rv).is_Continuous for rv in rvs]): from sympy.stats.crv import (ConditionalContinuousDomain, ContinuousPSpace) space = ContinuousPSpace domain = ConditionalContinuousDomain(self.domain, condition) elif any([pspace(rv).is_Discrete for rv in rvs]): from sympy.stats.drv import (ConditionalDiscreteDomain, DiscretePSpace) space = DiscretePSpace domain = ConditionalDiscreteDomain(self.domain, condition) elif all([pspace(rv).is_Finite for rv in rvs]): from sympy.stats.frv import FinitePSpace return FinitePSpace.conditional_space(self, condition) if normalize: replacement = {rv: Dummy(str(rv)) for rv in self.symbols} norm = domain.compute_expectation(self.pdf, **kwargs) pdf = self.pdf / norm.xreplace(replacement) # XXX: Converting symbols from set to tuple. The order matters to # Lambda though so we shouldn't be starting with a set here... density = Lambda(tuple(domain.symbols), pdf) return space(domain, density) class ProductDomain(RandomDomain): """ A domain resulting from the merger of two independent domains. See Also ======== sympy.stats.crv.ProductContinuousDomain sympy.stats.frv.ProductFiniteDomain """ is_ProductDomain = True def __new__(cls, *domains): # Flatten any product of products domains2 = [] for domain in domains: if not domain.is_ProductDomain: domains2.append(domain) else: domains2.extend(domain.domains) domains2 = FiniteSet(*domains2) if all(domain.is_Finite for domain in domains2): from sympy.stats.frv import ProductFiniteDomain cls = ProductFiniteDomain if all(domain.is_Continuous for domain in domains2): from sympy.stats.crv import ProductContinuousDomain cls = ProductContinuousDomain if all(domain.is_Discrete for domain in domains2): from sympy.stats.drv import ProductDiscreteDomain cls = ProductDiscreteDomain return Basic.__new__(cls, *domains2) @property def sym_domain_dict(self): return {symbol: domain for domain in self.domains for symbol in domain.symbols} @property def symbols(self): return FiniteSet(*[sym for domain in self.domains for sym in domain.symbols]) @property def domains(self): return self.args @property def set(self): return ProductSet(*(domain.set for domain in self.domains)) def __contains__(self, other): # Split event into each subdomain for domain in self.domains: # Collect the parts of this event which associate to this domain elem = frozenset([item for item in other if sympify(domain.symbols.contains(item[0])) is S.true]) # Test this sub-event if elem not in domain: return False # All subevents passed return True def as_boolean(self): return And(*[domain.as_boolean() for domain in self.domains]) def random_symbols(expr): """ Returns all RandomSymbols within a SymPy Expression. """ atoms = getattr(expr, 'atoms', None) if atoms is not None: comp = lambda rv: rv.symbol.name l = list(atoms(RandomSymbol)) return sorted(l, key=comp) else: return [] def pspace(expr): """ Returns the underlying Probability Space of a random expression. For internal use. Examples ======== >>> from sympy.stats import pspace, Normal >>> X = Normal('X', 0, 1) >>> pspace(2*X + 1) == X.pspace True """ expr = sympify(expr) if isinstance(expr, RandomSymbol) and expr.pspace is not None: return expr.pspace if expr.has(RandomMatrixSymbol): rm = list(expr.atoms(RandomMatrixSymbol))[0] return rm.pspace rvs = random_symbols(expr) if not rvs: raise ValueError("Expression containing Random Variable expected, not %s" % (expr)) # If only one space present if all(rv.pspace == rvs[0].pspace for rv in rvs): return rvs[0].pspace from sympy.stats.compound_rv import CompoundPSpace from sympy.stats.stochastic_process import StochasticPSpace for rv in rvs: if isinstance(rv.pspace, (CompoundPSpace, StochasticPSpace)): return rv.pspace # Otherwise make a product space return IndependentProductPSpace(*[rv.pspace for rv in rvs]) def sumsets(sets): """ Union of sets """ return frozenset().union(*sets) def rs_swap(a, b): """ Build a dictionary to swap RandomSymbols based on their underlying symbol. i.e. if ``X = ('x', pspace1)`` and ``Y = ('x', pspace2)`` then ``X`` and ``Y`` match and the key, value pair ``{X:Y}`` will appear in the result Inputs: collections a and b of random variables which share common symbols Output: dict mapping RVs in a to RVs in b """ d = {} for rsa in a: d[rsa] = [rsb for rsb in b if rsa.symbol == rsb.symbol][0] return d def given(expr, condition=None, **kwargs): r""" Conditional Random Expression. Explanation =========== From a random expression and a condition on that expression creates a new probability space from the condition and returns the same expression on that conditional probability space. Examples ======== >>> from sympy.stats import given, density, Die >>> X = Die('X', 6) >>> Y = given(X, X > 3) >>> density(Y).dict {4: 1/3, 5: 1/3, 6: 1/3} Following convention, if the condition is a random symbol then that symbol is considered fixed. >>> from sympy.stats import Normal >>> from sympy import pprint >>> from sympy.abc import z >>> X = Normal('X', 0, 1) >>> Y = Normal('Y', 0, 1) >>> pprint(density(X + Y, Y)(z), use_unicode=False) 2 -(-Y + z) ----------- ___ 2 \/ 2 *e ------------------ ____ 2*\/ pi """ if not is_random(condition) or pspace_independent(expr, condition): return expr if isinstance(condition, RandomSymbol): condition = Eq(condition, condition.symbol) condsymbols = random_symbols(condition) if (isinstance(condition, Equality) and len(condsymbols) == 1 and not isinstance(pspace(expr).domain, ConditionalDomain)): rv = tuple(condsymbols)[0] results = solveset(condition, rv) if isinstance(results, Intersection) and S.Reals in results.args: results = list(results.args[1]) sums = 0 for res in results: temp = expr.subs(rv, res) if temp == True: return True if temp != False: # XXX: This seems nonsensical but preserves existing behaviour # after the change that Relational is no longer a subclass of # Expr. Here expr is sometimes Relational and sometimes Expr # but we are trying to add them with +=. This needs to be # fixed somehow. if sums == 0 and isinstance(expr, Relational): sums = expr.subs(rv, res) else: sums += expr.subs(rv, res) if sums == 0: return False return sums # Get full probability space of both the expression and the condition fullspace = pspace(Tuple(expr, condition)) # Build new space given the condition space = fullspace.conditional_space(condition, **kwargs) # Dictionary to swap out RandomSymbols in expr with new RandomSymbols # That point to the new conditional space swapdict = rs_swap(fullspace.values, space.values) # Swap random variables in the expression expr = expr.xreplace(swapdict) return expr def expectation(expr, condition=None, numsamples=None, evaluate=True, **kwargs): """ Returns the expected value of a random expression. Parameters ========== expr : Expr containing RandomSymbols The expression of which you want to compute the expectation value given : Expr containing RandomSymbols A conditional expression. E(X, X>0) is expectation of X given X > 0 numsamples : int Enables sampling and approximates the expectation with this many samples evalf : Bool (defaults to True) If sampling return a number rather than a complex expression evaluate : Bool (defaults to True) In case of continuous systems return unevaluated integral Examples ======== >>> from sympy.stats import E, Die >>> X = Die('X', 6) >>> E(X) 7/2 >>> E(2*X + 1) 8 >>> E(X, X > 3) # Expectation of X given that it is above 3 5 """ if not is_random(expr): # expr isn't random? return expr kwargs['numsamples'] = numsamples from sympy.stats.symbolic_probability import Expectation if evaluate: return Expectation(expr, condition).doit(**kwargs) return Expectation(expr, condition) def probability(condition, given_condition=None, numsamples=None, evaluate=True, **kwargs): """ Probability that a condition is true, optionally given a second condition. Parameters ========== condition : Combination of Relationals containing RandomSymbols The condition of which you want to compute the probability given_condition : Combination of Relationals containing RandomSymbols A conditional expression. P(X > 1, X > 0) is expectation of X > 1 given X > 0 numsamples : int Enables sampling and approximates the probability with this many samples evaluate : Bool (defaults to True) In case of continuous systems return unevaluated integral Examples ======== >>> from sympy.stats import P, Die >>> from sympy import Eq >>> X, Y = Die('X', 6), Die('Y', 6) >>> P(X > 3) 1/2 >>> P(Eq(X, 5), X > 2) # Probability that X == 5 given that X > 2 1/4 >>> P(X > Y) 5/12 """ kwargs['numsamples'] = numsamples from sympy.stats.symbolic_probability import Probability if evaluate: return Probability(condition, given_condition).doit(**kwargs) ### TODO: Remove the user warnings in the future releases message = ("Since version 1.7, using `evaluate=False` returns `Probability` " "object. If you want unevaluated Integral/Sum use " "`P(condition, given_condition, evaluate=False).rewrite(Integral)`") warnings.warn(filldedent(message)) return Probability(condition, given_condition) class Density(Basic): expr = property(lambda self: self.args[0]) @property def condition(self): if len(self.args) > 1: return self.args[1] else: return None def doit(self, evaluate=True, **kwargs): from sympy.stats.random_matrix import RandomMatrixPSpace from sympy.stats.joint_rv import JointPSpace from sympy.stats.matrix_distributions import MatrixPSpace from sympy.stats.compound_rv import CompoundPSpace from sympy.stats.frv import SingleFiniteDistribution expr, condition = self.expr, self.condition if isinstance(expr, SingleFiniteDistribution): return expr.dict if condition is not None: # Recompute on new conditional expr expr = given(expr, condition, **kwargs) if not random_symbols(expr): return Lambda(x, DiracDelta(x - expr)) if isinstance(expr, RandomSymbol): if isinstance(expr.pspace, (SinglePSpace, JointPSpace, MatrixPSpace)) and \ hasattr(expr.pspace, 'distribution'): return expr.pspace.distribution elif isinstance(expr.pspace, RandomMatrixPSpace): return expr.pspace.model if isinstance(pspace(expr), CompoundPSpace): kwargs['compound_evaluate'] = evaluate result = pspace(expr).compute_density(expr, **kwargs) if evaluate and hasattr(result, 'doit'): return result.doit() else: return result def density(expr, condition=None, evaluate=True, numsamples=None, **kwargs): """ Probability density of a random expression, optionally given a second condition. Explanation =========== This density will take on different forms for different types of probability spaces. Discrete variables produce Dicts. Continuous variables produce Lambdas. Parameters ========== expr : Expr containing RandomSymbols The expression of which you want to compute the density value condition : Relational containing RandomSymbols A conditional expression. density(X > 1, X > 0) is density of X > 1 given X > 0 numsamples : int Enables sampling and approximates the density with this many samples Examples ======== >>> from sympy.stats import density, Die, Normal >>> from sympy import Symbol >>> x = Symbol('x') >>> D = Die('D', 6) >>> X = Normal(x, 0, 1) >>> density(D).dict {1: 1/6, 2: 1/6, 3: 1/6, 4: 1/6, 5: 1/6, 6: 1/6} >>> density(2*D).dict {2: 1/6, 4: 1/6, 6: 1/6, 8: 1/6, 10: 1/6, 12: 1/6} >>> density(X)(x) sqrt(2)*exp(-x**2/2)/(2*sqrt(pi)) """ if numsamples: return sampling_density(expr, condition, numsamples=numsamples, **kwargs) return Density(expr, condition).doit(evaluate=evaluate, **kwargs) def cdf(expr, condition=None, evaluate=True, **kwargs): """ Cumulative Distribution Function of a random expression. optionally given a second condition. Explanation =========== This density will take on different forms for different types of probability spaces. Discrete variables produce Dicts. Continuous variables produce Lambdas. Examples ======== >>> from sympy.stats import density, Die, Normal, cdf >>> D = Die('D', 6) >>> X = Normal('X', 0, 1) >>> density(D).dict {1: 1/6, 2: 1/6, 3: 1/6, 4: 1/6, 5: 1/6, 6: 1/6} >>> cdf(D) {1: 1/6, 2: 1/3, 3: 1/2, 4: 2/3, 5: 5/6, 6: 1} >>> cdf(3*D, D > 2) {9: 1/4, 12: 1/2, 15: 3/4, 18: 1} >>> cdf(X) Lambda(_z, erf(sqrt(2)*_z/2)/2 + 1/2) """ if condition is not None: # If there is a condition # Recompute on new conditional expr return cdf(given(expr, condition, **kwargs), **kwargs) # Otherwise pass work off to the ProbabilitySpace result = pspace(expr).compute_cdf(expr, **kwargs) if evaluate and hasattr(result, 'doit'): return result.doit() else: return result def characteristic_function(expr, condition=None, evaluate=True, **kwargs): """ Characteristic function of a random expression, optionally given a second condition. Returns a Lambda. Examples ======== >>> from sympy.stats import Normal, DiscreteUniform, Poisson, characteristic_function >>> X = Normal('X', 0, 1) >>> characteristic_function(X) Lambda(_t, exp(-_t**2/2)) >>> Y = DiscreteUniform('Y', [1, 2, 7]) >>> characteristic_function(Y) Lambda(_t, exp(7*_t*I)/3 + exp(2*_t*I)/3 + exp(_t*I)/3) >>> Z = Poisson('Z', 2) >>> characteristic_function(Z) Lambda(_t, exp(2*exp(_t*I) - 2)) """ if condition is not None: return characteristic_function(given(expr, condition, **kwargs), **kwargs) result = pspace(expr).compute_characteristic_function(expr, **kwargs) if evaluate and hasattr(result, 'doit'): return result.doit() else: return result def moment_generating_function(expr, condition=None, evaluate=True, **kwargs): if condition is not None: return moment_generating_function(given(expr, condition, **kwargs), **kwargs) result = pspace(expr).compute_moment_generating_function(expr, **kwargs) if evaluate and hasattr(result, 'doit'): return result.doit() else: return result def where(condition, given_condition=None, **kwargs): """ Returns the domain where a condition is True. Examples ======== >>> from sympy.stats import where, Die, Normal >>> from sympy import And >>> D1, D2 = Die('a', 6), Die('b', 6) >>> a, b = D1.symbol, D2.symbol >>> X = Normal('x', 0, 1) >>> where(X**2<1) Domain: (-1 < x) & (x < 1) >>> where(X**2<1).set Interval.open(-1, 1) >>> where(And(D1<=D2 , D2<3)) Domain: (Eq(a, 1) & Eq(b, 1)) | (Eq(a, 1) & Eq(b, 2)) | (Eq(a, 2) & Eq(b, 2)) """ if given_condition is not None: # If there is a condition # Recompute on new conditional expr return where(given(condition, given_condition, **kwargs), **kwargs) # Otherwise pass work off to the ProbabilitySpace return pspace(condition).where(condition, **kwargs) @doctest_depends_on(modules=('scipy',)) def sample(expr, condition=None, size=(), library='scipy', numsamples=1, seed=None, **kwargs): """ A realization of the random expression. Parameters ========== expr : Expression of random variables Expression from which sample is extracted condition : Expr containing RandomSymbols A conditional expression size : int, tuple Represents size of each sample in numsamples library : str - 'scipy' : Sample using scipy - 'numpy' : Sample using numpy - 'pymc3' : Sample using PyMC3 Choose any of the available options to sample from as string, by default is 'scipy' numsamples : int Number of samples, each with size as ``size``. The ``numsamples`` parameter is deprecated and is only provided for compatibility with v1.8. Use a list comprehension or an additional dimension in ``size`` instead. seed : An object to be used as seed by the given external library for sampling `expr`. Following is the list of possible types of object for the supported libraries, - 'scipy': int, numpy.random.RandomState, numpy.random.Generator - 'numpy': int, numpy.random.RandomState, numpy.random.Generator - 'pymc3': int Optional, by default None, in which case seed settings related to the given library will be used. No modifications to environment's global seed settings are done by this argument. Returns ======= sample: float/list/numpy.ndarray one sample or a collection of samples of the random expression. - sample(X) returns float/numpy.float64/numpy.int64 object. - sample(X, size=int/tuple) returns numpy.ndarray object. Examples ======== >>> from sympy.stats import Die, sample, Normal, Geometric >>> X, Y, Z = Die('X', 6), Die('Y', 6), Die('Z', 6) # Finite Random Variable >>> die_roll = sample(X + Y + Z) >>> die_roll # doctest: +SKIP 3 >>> N = Normal('N', 3, 4) # Continuous Random Variable >>> samp = sample(N) >>> samp in N.pspace.domain.set True >>> samp = sample(N, N>0) >>> samp > 0 True >>> samp_list = sample(N, size=4) >>> [sam in N.pspace.domain.set for sam in samp_list] [True, True, True, True] >>> sample(N, size = (2,3)) # doctest: +SKIP array([[5.42519758, 6.40207856, 4.94991743], [1.85819627, 6.83403519, 1.9412172 ]]) >>> G = Geometric('G', 0.5) # Discrete Random Variable >>> samp_list = sample(G, size=3) >>> samp_list # doctest: +SKIP [1, 3, 2] >>> [sam in G.pspace.domain.set for sam in samp_list] [True, True, True] >>> MN = Normal("MN", [3, 4], [[2, 1], [1, 2]]) # Joint Random Variable >>> samp_list = sample(MN, size=4) >>> samp_list # doctest: +SKIP [array([2.85768055, 3.38954165]), array([4.11163337, 4.3176591 ]), array([0.79115232, 1.63232916]), array([4.01747268, 3.96716083])] >>> [tuple(sam) in MN.pspace.domain.set for sam in samp_list] [True, True, True, True] .. versionchanged:: 1.7.0 sample used to return an iterator containing the samples instead of value. .. versionchanged:: 1.9.0 sample returns values or array of values instead of an iterator and numsamples is deprecated. """ iterator = sample_iter(expr, condition, size=size, library=library, numsamples=numsamples, seed=seed) if numsamples != 1: SymPyDeprecationWarning( feature="numsamples parameter", issue=21723, deprecated_since_version="1.9", useinstead="a list comprehension or an additional dimension in ``size``").warn() return [next(iterator) for i in range(numsamples)] return next(iterator) def quantile(expr, evaluate=True, **kwargs): r""" Return the :math:`p^{th}` order quantile of a probability distribution. Explanation =========== Quantile is defined as the value at which the probability of the random variable is less than or equal to the given probability. ..math:: Q(p) = inf{x \in (-\infty, \infty) such that p <= F(x)} Examples ======== >>> from sympy.stats import quantile, Die, Exponential >>> from sympy import Symbol, pprint >>> p = Symbol("p") >>> l = Symbol("lambda", positive=True) >>> X = Exponential("x", l) >>> quantile(X)(p) -log(1 - p)/lambda >>> D = Die("d", 6) >>> pprint(quantile(D)(p), use_unicode=False) /nan for Or(p > 1, p < 0) | | 1 for p <= 1/6 | | 2 for p <= 1/3 | < 3 for p <= 1/2 | | 4 for p <= 2/3 | | 5 for p <= 5/6 | \ 6 for p <= 1 """ result = pspace(expr).compute_quantile(expr, **kwargs) if evaluate and hasattr(result, 'doit'): return result.doit() else: return result def sample_iter(expr, condition=None, size=(), library='scipy', numsamples=S.Infinity, seed=None, **kwargs): """ Returns an iterator of realizations from the expression given a condition. Parameters ========== expr: Expr Random expression to be realized condition: Expr, optional A conditional expression size : int, tuple Represents size of each sample in numsamples numsamples: integer, optional Length of the iterator (defaults to infinity) seed : An object to be used as seed by the given external library for sampling `expr`. Following is the list of possible types of object for the supported libraries, - 'scipy': int, numpy.random.RandomState, numpy.random.Generator - 'numpy': int, numpy.random.RandomState, numpy.random.Generator - 'pymc3': int Optional, by default None, in which case seed settings related to the given library will be used. No modifications to environment's global seed settings are done by this argument. Examples ======== >>> from sympy.stats import Normal, sample_iter >>> X = Normal('X', 0, 1) >>> expr = X*X + 3 >>> iterator = sample_iter(expr, numsamples=3) # doctest: +SKIP >>> list(iterator) # doctest: +SKIP [12, 4, 7] Returns ======= sample_iter: iterator object iterator object containing the sample/samples of given expr See Also ======== sample sampling_P sampling_E """ from sympy.stats.joint_rv import JointRandomSymbol if not import_module(library): raise ValueError("Failed to import %s" % library) if condition is not None: ps = pspace(Tuple(expr, condition)) else: ps = pspace(expr) rvs = list(ps.values) if isinstance(expr, JointRandomSymbol): expr = expr.subs({expr: RandomSymbol(expr.symbol, expr.pspace)}) else: sub = {} for arg in expr.args: if isinstance(arg, JointRandomSymbol): sub[arg] = RandomSymbol(arg.symbol, arg.pspace) expr = expr.subs(sub) def fn_subs(*args): return expr.subs({rv: arg for rv, arg in zip(rvs, args)}) def given_fn_subs(*args): if condition is not None: return condition.subs({rv: arg for rv, arg in zip(rvs, args)}) return False if library == 'pymc3': # Currently unable to lambdify in pymc3 # TODO : Remove 'pymc3' when lambdify accepts 'pymc3' as module fn = lambdify(rvs, expr, **kwargs) else: fn = lambdify(rvs, expr, modules=library, **kwargs) if condition is not None: given_fn = lambdify(rvs, condition, **kwargs) def return_generator_infinite(): count = 0 _size = (1,)+((size,) if isinstance(size, int) else size) while count < numsamples: d = ps.sample(size=_size, library=library, seed=seed) # a dictionary that maps RVs to values args = [d[rv][0] for rv in rvs] if condition is not None: # Check that these values satisfy the condition # TODO: Replace the try-except block with only given_fn(*args) # once lambdify works with unevaluated SymPy objects. try: gd = given_fn(*args) except (NameError, TypeError): gd = given_fn_subs(*args) if gd != True and gd != False: raise ValueError( "Conditions must not contain free symbols") if not gd: # If the values don't satisfy then try again continue yield fn(*args) count += 1 def return_generator_finite(): faulty = True while faulty: d = ps.sample(size=(numsamples,) + ((size,) if isinstance(size, int) else size), library=library, seed=seed) # a dictionary that maps RVs to values faulty = False count = 0 while count < numsamples and not faulty: args = [d[rv][count] for rv in rvs] if condition is not None: # Check that these values satisfy the condition # TODO: Replace the try-except block with only given_fn(*args) # once lambdify works with unevaluated SymPy objects. try: gd = given_fn(*args) except (NameError, TypeError): gd = given_fn_subs(*args) if gd != True and gd != False: raise ValueError( "Conditions must not contain free symbols") if not gd: # If the values don't satisfy then try again faulty = True count += 1 count = 0 while count < numsamples: args = [d[rv][count] for rv in rvs] # TODO: Replace the try-except block with only fn(*args) # once lambdify works with unevaluated SymPy objects. try: yield fn(*args) except (NameError, TypeError): yield fn_subs(*args) count += 1 if numsamples is S.Infinity: return return_generator_infinite() return return_generator_finite() def sample_iter_lambdify(expr, condition=None, size=(), numsamples=S.Infinity, seed=None, **kwargs): return sample_iter(expr, condition=condition, size=size, numsamples=numsamples, seed=seed, **kwargs) def sample_iter_subs(expr, condition=None, size=(), numsamples=S.Infinity, seed=None, **kwargs): return sample_iter(expr, condition=condition, size=size, numsamples=numsamples, seed=seed, **kwargs) def sampling_P(condition, given_condition=None, library='scipy', numsamples=1, evalf=True, seed=None, **kwargs): """ Sampling version of P. See Also ======== P sampling_E sampling_density """ count_true = 0 count_false = 0 samples = sample_iter(condition, given_condition, library=library, numsamples=numsamples, seed=seed, **kwargs) for sample in samples: if sample: count_true += 1 else: count_false += 1 result = S(count_true) / numsamples if evalf: return result.evalf() else: return result def sampling_E(expr, given_condition=None, library='scipy', numsamples=1, evalf=True, seed=None, **kwargs): """ Sampling version of E. See Also ======== P sampling_P sampling_density """ samples = list(sample_iter(expr, given_condition, library=library, numsamples=numsamples, seed=seed, **kwargs)) result = Add(*[samp for samp in samples]) / numsamples if evalf: return result.evalf() else: return result def sampling_density(expr, given_condition=None, library='scipy', numsamples=1, seed=None, **kwargs): """ Sampling version of density. See Also ======== density sampling_P sampling_E """ results = {} for result in sample_iter(expr, given_condition, library=library, numsamples=numsamples, seed=seed, **kwargs): results[result] = results.get(result, 0) + 1 return results def dependent(a, b): """ Dependence of two random expressions. Two expressions are independent if knowledge of one does not change computations on the other. Examples ======== >>> from sympy.stats import Normal, dependent, given >>> from sympy import Tuple, Eq >>> X, Y = Normal('X', 0, 1), Normal('Y', 0, 1) >>> dependent(X, Y) False >>> dependent(2*X + Y, -Y) True >>> X, Y = given(Tuple(X, Y), Eq(X + Y, 3)) >>> dependent(X, Y) True See Also ======== independent """ if pspace_independent(a, b): return False z = Symbol('z', real=True) # Dependent if density is unchanged when one is given information about # the other return (density(a, Eq(b, z)) != density(a) or density(b, Eq(a, z)) != density(b)) def independent(a, b): """ Independence of two random expressions. Two expressions are independent if knowledge of one does not change computations on the other. Examples ======== >>> from sympy.stats import Normal, independent, given >>> from sympy import Tuple, Eq >>> X, Y = Normal('X', 0, 1), Normal('Y', 0, 1) >>> independent(X, Y) True >>> independent(2*X + Y, -Y) False >>> X, Y = given(Tuple(X, Y), Eq(X + Y, 3)) >>> independent(X, Y) False See Also ======== dependent """ return not dependent(a, b) def pspace_independent(a, b): """ Tests for independence between a and b by checking if their PSpaces have overlapping symbols. This is a sufficient but not necessary condition for independence and is intended to be used internally. Notes ===== pspace_independent(a, b) implies independent(a, b) independent(a, b) does not imply pspace_independent(a, b) """ a_symbols = set(pspace(b).symbols) b_symbols = set(pspace(a).symbols) if len(set(random_symbols(a)).intersection(random_symbols(b))) != 0: return False if len(a_symbols.intersection(b_symbols)) == 0: return True return None def rv_subs(expr, symbols=None): """ Given a random expression replace all random variables with their symbols. If symbols keyword is given restrict the swap to only the symbols listed. """ if symbols is None: symbols = random_symbols(expr) if not symbols: return expr swapdict = {rv: rv.symbol for rv in symbols} return expr.subs(swapdict) class NamedArgsMixin: _argnames = () # type: tTuple[str, ...] def __getattr__(self, attr): try: return self.args[self._argnames.index(attr)] except ValueError: raise AttributeError("'%s' object has no attribute '%s'" % ( type(self).__name__, attr)) class Distribution(Basic): def sample(self, size=(), library='scipy', seed=None): """ A random realization from the distribution """ module = import_module(library) if library in {'scipy', 'numpy', 'pymc3'} and module is None: raise ValueError("Failed to import %s" % library) if library == 'scipy': # scipy does not require map as it can handle using custom distributions. # However, we will still use a map where we can. # TODO: do this for drv.py and frv.py if necessary. # TODO: add more distributions here if there are more # See links below referring to sections beginning with "A common parametrization..." # I will remove all these comments if everything is ok. from sympy.stats.sampling.sample_scipy import do_sample_scipy import numpy if seed is None or isinstance(seed, int): rand_state = numpy.random.default_rng(seed=seed) else: rand_state = seed samps = do_sample_scipy(self, size, rand_state) elif library == 'numpy': from sympy.stats.sampling.sample_numpy import do_sample_numpy import numpy if seed is None or isinstance(seed, int): rand_state = numpy.random.default_rng(seed=seed) else: rand_state = seed _size = None if size == () else size samps = do_sample_numpy(self, _size, rand_state) elif library == 'pymc3': from sympy.stats.sampling.sample_pymc3 import do_sample_pymc3 import logging logging.getLogger("pymc3").setLevel(logging.ERROR) import pymc3 with pymc3.Model(): if do_sample_pymc3(self): samps = pymc3.sample(draws=prod(size), chains=1, compute_convergence_checks=False, progressbar=False, random_seed=seed, return_inferencedata=False)[:]['X'] samps = samps.reshape(size) else: samps = None else: raise NotImplementedError("Sampling from %s is not supported yet." % str(library)) if samps is not None: return samps raise NotImplementedError( "Sampling for %s is not currently implemented from %s" % (self, library)) def _value_check(condition, message): """ Raise a ValueError with message if condition is False, else return True if all conditions were True, else False. Examples ======== >>> from sympy.stats.rv import _value_check >>> from sympy.abc import a, b, c >>> from sympy import And, Dummy >>> _value_check(2 < 3, '') True Here, the condition is not False, but it doesn't evaluate to True so False is returned (but no error is raised). So checking if the return value is True or False will tell you if all conditions were evaluated. >>> _value_check(a < b, '') False In this case the condition is False so an error is raised: >>> r = Dummy(real=True) >>> _value_check(r < r - 1, 'condition is not true') Traceback (most recent call last): ... ValueError: condition is not true If no condition of many conditions must be False, they can be checked by passing them as an iterable: >>> _value_check((a < 0, b < 0, c < 0), '') False The iterable can be a generator, too: >>> _value_check((i < 0 for i in (a, b, c)), '') False The following are equivalent to the above but do not pass an iterable: >>> all(_value_check(i < 0, '') for i in (a, b, c)) False >>> _value_check(And(a < 0, b < 0, c < 0), '') False """ from sympy.core.compatibility import iterable from sympy.core.logic import fuzzy_and if not iterable(condition): condition = [condition] truth = fuzzy_and(condition) if truth == False: raise ValueError(message) return truth == True def _symbol_converter(sym): """ Casts the parameter to Symbol if it is 'str' otherwise no operation is performed on it. Parameters ========== sym The parameter to be converted. Returns ======= Symbol the parameter converted to Symbol. Raises ====== TypeError If the parameter is not an instance of both str and Symbol. Examples ======== >>> from sympy import Symbol >>> from sympy.stats.rv import _symbol_converter >>> s = _symbol_converter('s') >>> isinstance(s, Symbol) True >>> _symbol_converter(1) Traceback (most recent call last): ... TypeError: 1 is neither a Symbol nor a string >>> r = Symbol('r') >>> isinstance(r, Symbol) True """ if isinstance(sym, str): sym = Symbol(sym) if not isinstance(sym, Symbol): raise TypeError("%s is neither a Symbol nor a string"%(sym)) return sym def sample_stochastic_process(process): """ This function is used to sample from stochastic process. Parameters ========== process: StochasticProcess Process used to extract the samples. It must be an instance of StochasticProcess Examples ======== >>> from sympy.stats import sample_stochastic_process, DiscreteMarkovChain >>> from sympy import Matrix >>> T = Matrix([[0.5, 0.2, 0.3],[0.2, 0.5, 0.3],[0.2, 0.3, 0.5]]) >>> Y = DiscreteMarkovChain("Y", [0, 1, 2], T) >>> next(sample_stochastic_process(Y)) in Y.state_space # doctest: +SKIP True >>> next(sample_stochastic_process(Y)) # doctest: +SKIP 0 >>> next(sample_stochastic_process(Y)) # doctest: +SKIP 2 Returns ======= sample: iterator object iterator object containing the sample of given process """ from sympy.stats.stochastic_process_types import StochasticProcess if not isinstance(process, StochasticProcess): raise ValueError("Process must be an instance of Stochastic Process") return process.sample()
f98302c087a28daed6e01c0b572cfb12e1b76564809d14c77b4ebac566aa8ff9
""" Joint Random Variables Module See Also ======== sympy.stats.rv sympy.stats.frv sympy.stats.crv sympy.stats.drv """ from sympy import (Basic, Lambda, sympify, Indexed, Symbol, ProductSet, S, Dummy, prod) from sympy.concrete.products import Product from sympy.concrete.summations import Sum, summation from sympy.core.compatibility import iterable from sympy.core.containers import Tuple from sympy.integrals.integrals import Integral, integrate from sympy.matrices import ImmutableMatrix, matrix2numpy, list2numpy from sympy.stats.crv import SingleContinuousDistribution, SingleContinuousPSpace from sympy.stats.drv import SingleDiscreteDistribution, SingleDiscretePSpace from sympy.stats.rv import (ProductPSpace, NamedArgsMixin, Distribution, ProductDomain, RandomSymbol, random_symbols, SingleDomain, _symbol_converter) from sympy.utilities.misc import filldedent from sympy.external import import_module # __all__ = ['marginal_distribution'] class JointPSpace(ProductPSpace): """ Represents a joint probability space. Represented using symbols for each component and a distribution. """ def __new__(cls, sym, dist): if isinstance(dist, SingleContinuousDistribution): return SingleContinuousPSpace(sym, dist) if isinstance(dist, SingleDiscreteDistribution): return SingleDiscretePSpace(sym, dist) sym = _symbol_converter(sym) return Basic.__new__(cls, sym, dist) @property def set(self): return self.domain.set @property def symbol(self): return self.args[0] @property def distribution(self): return self.args[1] @property def value(self): return JointRandomSymbol(self.symbol, self) @property def component_count(self): _set = self.distribution.set if isinstance(_set, ProductSet): return S(len(_set.args)) elif isinstance(_set, Product): return _set.limits[0][-1] return S.One @property def pdf(self): sym = [Indexed(self.symbol, i) for i in range(self.component_count)] return self.distribution(*sym) @property def domain(self): rvs = random_symbols(self.distribution) if not rvs: return SingleDomain(self.symbol, self.distribution.set) return ProductDomain(*[rv.pspace.domain for rv in rvs]) def component_domain(self, index): return self.set.args[index] def marginal_distribution(self, *indices): count = self.component_count if count.atoms(Symbol): raise ValueError("Marginal distributions cannot be computed " "for symbolic dimensions. It is a work under progress.") orig = [Indexed(self.symbol, i) for i in range(count)] all_syms = [Symbol(str(i)) for i in orig] replace_dict = dict(zip(all_syms, orig)) sym = tuple(Symbol(str(Indexed(self.symbol, i))) for i in indices) limits = list([i,] for i in all_syms if i not in sym) index = 0 for i in range(count): if i not in indices: limits[index].append(self.distribution.set.args[i]) limits[index] = tuple(limits[index]) index += 1 if self.distribution.is_Continuous: f = Lambda(sym, integrate(self.distribution(*all_syms), *limits)) elif self.distribution.is_Discrete: f = Lambda(sym, summation(self.distribution(*all_syms), *limits)) return f.xreplace(replace_dict) def compute_expectation(self, expr, rvs=None, evaluate=False, **kwargs): syms = tuple(self.value[i] for i in range(self.component_count)) rvs = rvs or syms if not any([i in rvs for i in syms]): return expr expr = expr*self.pdf for rv in rvs: if isinstance(rv, Indexed): expr = expr.xreplace({rv: Indexed(str(rv.base), rv.args[1])}) elif isinstance(rv, RandomSymbol): expr = expr.xreplace({rv: rv.symbol}) if self.value in random_symbols(expr): raise NotImplementedError(filldedent(''' Expectations of expression with unindexed joint random symbols cannot be calculated yet.''')) limits = tuple((Indexed(str(rv.base),rv.args[1]), self.distribution.set.args[rv.args[1]]) for rv in syms) return Integral(expr, *limits) def where(self, condition): raise NotImplementedError() def compute_density(self, expr): raise NotImplementedError() def sample(self, size=(), library='scipy', seed=None): """ Internal sample method Returns dictionary mapping RandomSymbol to realization value. """ return {RandomSymbol(self.symbol, self): self.distribution.sample(size, library=library, seed=seed)} def probability(self, condition): raise NotImplementedError() class SampleJointScipy: """Returns the sample from scipy of the given distribution""" def __new__(cls, dist, size, seed=None): return cls._sample_scipy(dist, size, seed) @classmethod def _sample_scipy(cls, dist, size, seed): """Sample from SciPy.""" import numpy if seed is None or isinstance(seed, int): rand_state = numpy.random.default_rng(seed=seed) else: rand_state = seed from scipy import stats as scipy_stats scipy_rv_map = { 'MultivariateNormalDistribution': lambda dist, size: scipy_stats.multivariate_normal.rvs( mean=matrix2numpy(dist.mu).flatten(), cov=matrix2numpy(dist.sigma), size=size, random_state=rand_state), 'MultivariateBetaDistribution': lambda dist, size: scipy_stats.dirichlet.rvs( alpha=list2numpy(dist.alpha, float).flatten(), size=size, random_state=rand_state), 'MultinomialDistribution': lambda dist, size: scipy_stats.multinomial.rvs( n=int(dist.n), p=list2numpy(dist.p, float).flatten(), size=size, random_state=rand_state) } sample_shape = { 'MultivariateNormalDistribution': lambda dist: matrix2numpy(dist.mu).flatten().shape, 'MultivariateBetaDistribution': lambda dist: list2numpy(dist.alpha).flatten().shape, 'MultinomialDistribution': lambda dist: list2numpy(dist.p).flatten().shape } dist_list = scipy_rv_map.keys() if dist.__class__.__name__ not in dist_list: return None samples = scipy_rv_map[dist.__class__.__name__](dist, size) return samples.reshape(size + sample_shape[dist.__class__.__name__](dist)) class SampleJointNumpy: """Returns the sample from numpy of the given distribution""" def __new__(cls, dist, size, seed=None): return cls._sample_numpy(dist, size, seed) @classmethod def _sample_numpy(cls, dist, size, seed): """Sample from NumPy.""" import numpy if seed is None or isinstance(seed, int): rand_state = numpy.random.default_rng(seed=seed) else: rand_state = seed numpy_rv_map = { 'MultivariateNormalDistribution': lambda dist, size: rand_state.multivariate_normal( mean=matrix2numpy(dist.mu, float).flatten(), cov=matrix2numpy(dist.sigma, float), size=size), 'MultivariateBetaDistribution': lambda dist, size: rand_state.dirichlet( alpha=list2numpy(dist.alpha, float).flatten(), size=size), 'MultinomialDistribution': lambda dist, size: rand_state.multinomial( n=int(dist.n), pvals=list2numpy(dist.p, float).flatten(), size=size) } sample_shape = { 'MultivariateNormalDistribution': lambda dist: matrix2numpy(dist.mu).flatten().shape, 'MultivariateBetaDistribution': lambda dist: list2numpy(dist.alpha).flatten().shape, 'MultinomialDistribution': lambda dist: list2numpy(dist.p).flatten().shape } dist_list = numpy_rv_map.keys() if dist.__class__.__name__ not in dist_list: return None samples = numpy_rv_map[dist.__class__.__name__](dist, prod(size)) return samples.reshape(size + sample_shape[dist.__class__.__name__](dist)) class SampleJointPymc: """Returns the sample from pymc3 of the given distribution""" def __new__(cls, dist, size, seed=None): return cls._sample_pymc3(dist, size, seed) @classmethod def _sample_pymc3(cls, dist, size, seed): """Sample from PyMC3.""" import pymc3 pymc3_rv_map = { 'MultivariateNormalDistribution': lambda dist: pymc3.MvNormal('X', mu=matrix2numpy(dist.mu, float).flatten(), cov=matrix2numpy(dist.sigma, float), shape=(1, dist.mu.shape[0])), 'MultivariateBetaDistribution': lambda dist: pymc3.Dirichlet('X', a=list2numpy(dist.alpha, float).flatten()), 'MultinomialDistribution': lambda dist: pymc3.Multinomial('X', n=int(dist.n), p=list2numpy(dist.p, float).flatten(), shape=(1, len(dist.p))) } sample_shape = { 'MultivariateNormalDistribution': lambda dist: matrix2numpy(dist.mu).flatten().shape, 'MultivariateBetaDistribution': lambda dist: list2numpy(dist.alpha).flatten().shape, 'MultinomialDistribution': lambda dist: list2numpy(dist.p).flatten().shape } dist_list = pymc3_rv_map.keys() if dist.__class__.__name__ not in dist_list: return None import logging logging.getLogger("pymc3").setLevel(logging.ERROR) with pymc3.Model(): pymc3_rv_map[dist.__class__.__name__](dist) samples = pymc3.sample(draws=prod(size), chains=1, progressbar=False, random_seed=seed, return_inferencedata=False, compute_convergence_checks=False)[:]['X'] return samples.reshape(size + sample_shape[dist.__class__.__name__](dist)) _get_sample_class_jrv = { 'scipy': SampleJointScipy, 'pymc3': SampleJointPymc, 'numpy': SampleJointNumpy } class JointDistribution(Distribution, NamedArgsMixin): """ Represented by the random variables part of the joint distribution. Contains methods for PDF, CDF, sampling, marginal densities, etc. """ _argnames = ('pdf', ) def __new__(cls, *args): args = list(map(sympify, args)) for i in range(len(args)): if isinstance(args[i], list): args[i] = ImmutableMatrix(args[i]) return Basic.__new__(cls, *args) @property def domain(self): return ProductDomain(self.symbols) @property def pdf(self): return self.density.args[1] def cdf(self, other): if not isinstance(other, dict): raise ValueError("%s should be of type dict, got %s"%(other, type(other))) rvs = other.keys() _set = self.domain.set.sets expr = self.pdf(tuple(i.args[0] for i in self.symbols)) for i in range(len(other)): if rvs[i].is_Continuous: density = Integral(expr, (rvs[i], _set[i].inf, other[rvs[i]])) elif rvs[i].is_Discrete: density = Sum(expr, (rvs[i], _set[i].inf, other[rvs[i]])) return density def sample(self, size=(), library='scipy', seed=None): """ A random realization from the distribution """ libraries = ['scipy', 'numpy', 'pymc3'] if library not in libraries: raise NotImplementedError("Sampling from %s is not supported yet." % str(library)) if not import_module(library): raise ValueError("Failed to import %s" % library) samps = _get_sample_class_jrv[library](self, size, seed=seed) if samps is not None: return samps raise NotImplementedError( "Sampling for %s is not currently implemented from %s" % (self.__class__.__name__, library) ) def __call__(self, *args): return self.pdf(*args) class JointRandomSymbol(RandomSymbol): """ Representation of random symbols with joint probability distributions to allow indexing." """ def __getitem__(self, key): if isinstance(self.pspace, JointPSpace): if (self.pspace.component_count <= key) == True: raise ValueError("Index keys for %s can only up to %s." % (self.name, self.pspace.component_count - 1)) return Indexed(self, key) class MarginalDistribution(Distribution): """ Represents the marginal distribution of a joint probability space. Initialised using a probability distribution and random variables(or their indexed components) which should be a part of the resultant distribution. """ def __new__(cls, dist, *rvs): if len(rvs) == 1 and iterable(rvs[0]): rvs = tuple(rvs[0]) if not all([isinstance(rv, (Indexed, RandomSymbol))] for rv in rvs): raise ValueError(filldedent('''Marginal distribution can be intitialised only in terms of random variables or indexed random variables''')) rvs = Tuple.fromiter(rv for rv in rvs) if not isinstance(dist, JointDistribution) and len(random_symbols(dist)) == 0: return dist return Basic.__new__(cls, dist, rvs) def check(self): pass @property def set(self): rvs = [i for i in self.args[1] if isinstance(i, RandomSymbol)] return ProductSet(*[rv.pspace.set for rv in rvs]) @property def symbols(self): rvs = self.args[1] return {rv.pspace.symbol for rv in rvs} def pdf(self, *x): expr, rvs = self.args[0], self.args[1] marginalise_out = [i for i in random_symbols(expr) if i not in rvs] if isinstance(expr, JointDistribution): count = len(expr.domain.args) x = Dummy('x', real=True, finite=True) syms = tuple(Indexed(x, i) for i in count) expr = expr.pdf(syms) else: syms = tuple(rv.pspace.symbol if isinstance(rv, RandomSymbol) else rv.args[0] for rv in rvs) return Lambda(syms, self.compute_pdf(expr, marginalise_out))(*x) def compute_pdf(self, expr, rvs): for rv in rvs: lpdf = 1 if isinstance(rv, RandomSymbol): lpdf = rv.pspace.pdf expr = self.marginalise_out(expr*lpdf, rv) return expr def marginalise_out(self, expr, rv): from sympy.concrete.summations import Sum if isinstance(rv, RandomSymbol): dom = rv.pspace.set elif isinstance(rv, Indexed): dom = rv.base.component_domain( rv.pspace.component_domain(rv.args[1])) expr = expr.xreplace({rv: rv.pspace.symbol}) if rv.pspace.is_Continuous: #TODO: Modify to support integration #for all kinds of sets. expr = Integral(expr, (rv.pspace.symbol, dom)) elif rv.pspace.is_Discrete: #incorporate this into `Sum`/`summation` if dom in (S.Integers, S.Naturals, S.Naturals0): dom = (dom.inf, dom.sup) expr = Sum(expr, (rv.pspace.symbol, dom)) return expr def __call__(self, *args): return self.pdf(*args)
fa5f027f34d7ba2709d9a9dbe7f6e084e462b2a0900b1364c41ae0e1dcf2435c
import itertools from sympy import (Expr, Add, Mul, S, Integral, Eq, Sum, Symbol, expand as _expand, Not) from sympy.core.compatibility import default_sort_key from sympy.core.parameters import global_parameters from sympy.core.sympify import _sympify from sympy.core.relational import Relational from sympy.logic.boolalg import Boolean from sympy.stats import variance, covariance from sympy.stats.rv import (RandomSymbol, pspace, dependent, given, sampling_E, RandomIndexedSymbol, is_random, PSpace, sampling_P, random_symbols) __all__ = ['Probability', 'Expectation', 'Variance', 'Covariance'] @is_random.register(Expr) def _(x): atoms = x.free_symbols if len(atoms) == 1 and next(iter(atoms)) == x: return False return any([is_random(i) for i in atoms]) @is_random.register(RandomSymbol) # type: ignore def _(x): return True class Probability(Expr): """ Symbolic expression for the probability. Examples ======== >>> from sympy.stats import Probability, Normal >>> from sympy import Integral >>> X = Normal("X", 0, 1) >>> prob = Probability(X > 1) >>> prob Probability(X > 1) Integral representation: >>> prob.rewrite(Integral) Integral(sqrt(2)*exp(-_z**2/2)/(2*sqrt(pi)), (_z, 1, oo)) Evaluation of the integral: >>> prob.evaluate_integral() sqrt(2)*(-sqrt(2)*sqrt(pi)*erf(sqrt(2)/2) + sqrt(2)*sqrt(pi))/(4*sqrt(pi)) """ def __new__(cls, prob, condition=None, **kwargs): prob = _sympify(prob) if condition is None: obj = Expr.__new__(cls, prob) else: condition = _sympify(condition) obj = Expr.__new__(cls, prob, condition) obj._condition = condition return obj def doit(self, **hints): condition = self.args[0] given_condition = self._condition numsamples = hints.get('numsamples', False) for_rewrite = not hints.get('for_rewrite', False) if isinstance(condition, Not): return S.One - self.func(condition.args[0], given_condition, evaluate=for_rewrite).doit(**hints) if condition.has(RandomIndexedSymbol): return pspace(condition).probability(condition, given_condition, evaluate=for_rewrite) if isinstance(given_condition, RandomSymbol): condrv = random_symbols(condition) if len(condrv) == 1 and condrv[0] == given_condition: from sympy.stats.frv_types import BernoulliDistribution return BernoulliDistribution(self.func(condition).doit(**hints), 0, 1) if any([dependent(rv, given_condition) for rv in condrv]): return Probability(condition, given_condition) else: return Probability(condition).doit() if given_condition is not None and \ not isinstance(given_condition, (Relational, Boolean)): raise ValueError("%s is not a relational or combination of relationals" % (given_condition)) if given_condition == False or condition is S.false: return S.Zero if not isinstance(condition, (Relational, Boolean)): raise ValueError("%s is not a relational or combination of relationals" % (condition)) if condition is S.true: return S.One if numsamples: return sampling_P(condition, given_condition, numsamples=numsamples) if given_condition is not None: # If there is a condition # Recompute on new conditional expr return Probability(given(condition, given_condition)).doit() # Otherwise pass work off to the ProbabilitySpace if pspace(condition) == PSpace(): return Probability(condition, given_condition) result = pspace(condition).probability(condition) if hasattr(result, 'doit') and for_rewrite: return result.doit() else: return result def _eval_rewrite_as_Integral(self, arg, condition=None, **kwargs): return self.func(arg, condition=condition).doit(for_rewrite=True) _eval_rewrite_as_Sum = _eval_rewrite_as_Integral def evaluate_integral(self): return self.rewrite(Integral).doit() class Expectation(Expr): """ Symbolic expression for the expectation. Examples ======== >>> from sympy.stats import Expectation, Normal, Probability, Poisson >>> from sympy import symbols, Integral, Sum >>> mu = symbols("mu") >>> sigma = symbols("sigma", positive=True) >>> X = Normal("X", mu, sigma) >>> Expectation(X) Expectation(X) >>> Expectation(X).evaluate_integral().simplify() mu To get the integral expression of the expectation: >>> Expectation(X).rewrite(Integral) Integral(sqrt(2)*X*exp(-(X - mu)**2/(2*sigma**2))/(2*sqrt(pi)*sigma), (X, -oo, oo)) The same integral expression, in more abstract terms: >>> Expectation(X).rewrite(Probability) Integral(x*Probability(Eq(X, x)), (x, -oo, oo)) To get the Summation expression of the expectation for discrete random variables: >>> lamda = symbols('lamda', positive=True) >>> Z = Poisson('Z', lamda) >>> Expectation(Z).rewrite(Sum) Sum(Z*lamda**Z*exp(-lamda)/factorial(Z), (Z, 0, oo)) This class is aware of some properties of the expectation: >>> from sympy.abc import a >>> Expectation(a*X) Expectation(a*X) >>> Y = Normal("Y", 1, 2) >>> Expectation(X + Y) Expectation(X + Y) To expand the ``Expectation`` into its expression, use ``expand()``: >>> Expectation(X + Y).expand() Expectation(X) + Expectation(Y) >>> Expectation(a*X + Y).expand() a*Expectation(X) + Expectation(Y) >>> Expectation(a*X + Y) Expectation(a*X + Y) >>> Expectation((X + Y)*(X - Y)).expand() Expectation(X**2) - Expectation(Y**2) To evaluate the ``Expectation``, use ``doit()``: >>> Expectation(X + Y).doit() mu + 1 >>> Expectation(X + Expectation(Y + Expectation(2*X))).doit() 3*mu + 1 To prevent evaluating nested ``Expectation``, use ``doit(deep=False)`` >>> Expectation(X + Expectation(Y)).doit(deep=False) mu + Expectation(Expectation(Y)) >>> Expectation(X + Expectation(Y + Expectation(2*X))).doit(deep=False) mu + Expectation(Expectation(Y + Expectation(2*X))) """ def __new__(cls, expr, condition=None, **kwargs): expr = _sympify(expr) if expr.is_Matrix: from sympy.stats.symbolic_multivariate_probability import ExpectationMatrix return ExpectationMatrix(expr, condition) if condition is None: if not is_random(expr): return expr obj = Expr.__new__(cls, expr) else: condition = _sympify(condition) obj = Expr.__new__(cls, expr, condition) obj._condition = condition return obj def expand(self, **hints): expr = self.args[0] condition = self._condition if not is_random(expr): return expr if isinstance(expr, Add): return Add.fromiter(Expectation(a, condition=condition).expand() for a in expr.args) expand_expr = _expand(expr) if isinstance(expand_expr, Add): return Add.fromiter(Expectation(a, condition=condition).expand() for a in expand_expr.args) elif isinstance(expr, Mul): rv = [] nonrv = [] for a in expr.args: if is_random(a): rv.append(a) else: nonrv.append(a) return Mul.fromiter(nonrv)*Expectation(Mul.fromiter(rv), condition=condition) return self def doit(self, **hints): deep = hints.get('deep', True) condition = self._condition expr = self.args[0] numsamples = hints.get('numsamples', False) for_rewrite = not hints.get('for_rewrite', False) if deep: expr = expr.doit(**hints) if not is_random(expr) or isinstance(expr, Expectation): # expr isn't random? return expr if numsamples: # Computing by monte carlo sampling? evalf = hints.get('evalf', True) return sampling_E(expr, condition, numsamples=numsamples, evalf=evalf) if expr.has(RandomIndexedSymbol): return pspace(expr).compute_expectation(expr, condition) # Create new expr and recompute E if condition is not None: # If there is a condition return self.func(given(expr, condition)).doit(**hints) # A few known statements for efficiency if expr.is_Add: # We know that E is Linear return Add(*[self.func(arg, condition).doit(**hints) if not isinstance(arg, Expectation) else self.func(arg, condition) for arg in expr.args]) if expr.is_Mul: if expr.atoms(Expectation): return expr if pspace(expr) == PSpace(): return self.func(expr) # Otherwise case is simple, pass work off to the ProbabilitySpace result = pspace(expr).compute_expectation(expr, evaluate=for_rewrite) if hasattr(result, 'doit') and for_rewrite: return result.doit(**hints) else: return result def _eval_rewrite_as_Probability(self, arg, condition=None, **kwargs): rvs = arg.atoms(RandomSymbol) if len(rvs) > 1: raise NotImplementedError() if len(rvs) == 0: return arg rv = rvs.pop() if rv.pspace is None: raise ValueError("Probability space not known") symbol = rv.symbol if symbol.name[0].isupper(): symbol = Symbol(symbol.name.lower()) else : symbol = Symbol(symbol.name + "_1") if rv.pspace.is_Continuous: return Integral(arg.replace(rv, symbol)*Probability(Eq(rv, symbol), condition), (symbol, rv.pspace.domain.set.inf, rv.pspace.domain.set.sup)) else: if rv.pspace.is_Finite: raise NotImplementedError else: return Sum(arg.replace(rv, symbol)*Probability(Eq(rv, symbol), condition), (symbol, rv.pspace.domain.set.inf, rv.pspace.set.sup)) def _eval_rewrite_as_Integral(self, arg, condition=None, **kwargs): return self.func(arg, condition=condition).doit(deep=False, for_rewrite=True) _eval_rewrite_as_Sum = _eval_rewrite_as_Integral # For discrete this will be Sum def evaluate_integral(self): return self.rewrite(Integral).doit() evaluate_sum = evaluate_integral class Variance(Expr): """ Symbolic expression for the variance. Examples ======== >>> from sympy import symbols, Integral >>> from sympy.stats import Normal, Expectation, Variance, Probability >>> mu = symbols("mu", positive=True) >>> sigma = symbols("sigma", positive=True) >>> X = Normal("X", mu, sigma) >>> Variance(X) Variance(X) >>> Variance(X).evaluate_integral() sigma**2 Integral representation of the underlying calculations: >>> Variance(X).rewrite(Integral) Integral(sqrt(2)*(X - Integral(sqrt(2)*X*exp(-(X - mu)**2/(2*sigma**2))/(2*sqrt(pi)*sigma), (X, -oo, oo)))**2*exp(-(X - mu)**2/(2*sigma**2))/(2*sqrt(pi)*sigma), (X, -oo, oo)) Integral representation, without expanding the PDF: >>> Variance(X).rewrite(Probability) -Integral(x*Probability(Eq(X, x)), (x, -oo, oo))**2 + Integral(x**2*Probability(Eq(X, x)), (x, -oo, oo)) Rewrite the variance in terms of the expectation >>> Variance(X).rewrite(Expectation) -Expectation(X)**2 + Expectation(X**2) Some transformations based on the properties of the variance may happen: >>> from sympy.abc import a >>> Y = Normal("Y", 0, 1) >>> Variance(a*X) Variance(a*X) To expand the variance in its expression, use ``expand()``: >>> Variance(a*X).expand() a**2*Variance(X) >>> Variance(X + Y) Variance(X + Y) >>> Variance(X + Y).expand() 2*Covariance(X, Y) + Variance(X) + Variance(Y) """ def __new__(cls, arg, condition=None, **kwargs): arg = _sympify(arg) if arg.is_Matrix: from sympy.stats.symbolic_multivariate_probability import VarianceMatrix return VarianceMatrix(arg, condition) if condition is None: obj = Expr.__new__(cls, arg) else: condition = _sympify(condition) obj = Expr.__new__(cls, arg, condition) obj._condition = condition return obj def expand(self, **hints): arg = self.args[0] condition = self._condition if not is_random(arg): return S.Zero if isinstance(arg, RandomSymbol): return self elif isinstance(arg, Add): rv = [] for a in arg.args: if is_random(a): rv.append(a) variances = Add(*map(lambda xv: Variance(xv, condition).expand(), rv)) map_to_covar = lambda x: 2*Covariance(*x, condition=condition).expand() covariances = Add(*map(map_to_covar, itertools.combinations(rv, 2))) return variances + covariances elif isinstance(arg, Mul): nonrv = [] rv = [] for a in arg.args: if is_random(a): rv.append(a) else: nonrv.append(a**2) if len(rv) == 0: return S.Zero return Mul.fromiter(nonrv)*Variance(Mul.fromiter(rv), condition) # this expression contains a RandomSymbol somehow: return self def _eval_rewrite_as_Expectation(self, arg, condition=None, **kwargs): e1 = Expectation(arg**2, condition) e2 = Expectation(arg, condition)**2 return e1 - e2 def _eval_rewrite_as_Probability(self, arg, condition=None, **kwargs): return self.rewrite(Expectation).rewrite(Probability) def _eval_rewrite_as_Integral(self, arg, condition=None, **kwargs): return variance(self.args[0], self._condition, evaluate=False) _eval_rewrite_as_Sum = _eval_rewrite_as_Integral def evaluate_integral(self): return self.rewrite(Integral).doit() class Covariance(Expr): """ Symbolic expression for the covariance. Examples ======== >>> from sympy.stats import Covariance >>> from sympy.stats import Normal >>> X = Normal("X", 3, 2) >>> Y = Normal("Y", 0, 1) >>> Z = Normal("Z", 0, 1) >>> W = Normal("W", 0, 1) >>> cexpr = Covariance(X, Y) >>> cexpr Covariance(X, Y) Evaluate the covariance, `X` and `Y` are independent, therefore zero is the result: >>> cexpr.evaluate_integral() 0 Rewrite the covariance expression in terms of expectations: >>> from sympy.stats import Expectation >>> cexpr.rewrite(Expectation) Expectation(X*Y) - Expectation(X)*Expectation(Y) In order to expand the argument, use ``expand()``: >>> from sympy.abc import a, b, c, d >>> Covariance(a*X + b*Y, c*Z + d*W) Covariance(a*X + b*Y, c*Z + d*W) >>> Covariance(a*X + b*Y, c*Z + d*W).expand() a*c*Covariance(X, Z) + a*d*Covariance(W, X) + b*c*Covariance(Y, Z) + b*d*Covariance(W, Y) This class is aware of some properties of the covariance: >>> Covariance(X, X).expand() Variance(X) >>> Covariance(a*X, b*Y).expand() a*b*Covariance(X, Y) """ def __new__(cls, arg1, arg2, condition=None, **kwargs): arg1 = _sympify(arg1) arg2 = _sympify(arg2) if arg1.is_Matrix or arg2.is_Matrix: from sympy.stats.symbolic_multivariate_probability import CrossCovarianceMatrix return CrossCovarianceMatrix(arg1, arg2, condition) if kwargs.pop('evaluate', global_parameters.evaluate): arg1, arg2 = sorted([arg1, arg2], key=default_sort_key) if condition is None: obj = Expr.__new__(cls, arg1, arg2) else: condition = _sympify(condition) obj = Expr.__new__(cls, arg1, arg2, condition) obj._condition = condition return obj def expand(self, **hints): arg1 = self.args[0] arg2 = self.args[1] condition = self._condition if arg1 == arg2: return Variance(arg1, condition).expand() if not is_random(arg1): return S.Zero if not is_random(arg2): return S.Zero arg1, arg2 = sorted([arg1, arg2], key=default_sort_key) if isinstance(arg1, RandomSymbol) and isinstance(arg2, RandomSymbol): return Covariance(arg1, arg2, condition) coeff_rv_list1 = self._expand_single_argument(arg1.expand()) coeff_rv_list2 = self._expand_single_argument(arg2.expand()) addends = [a*b*Covariance(*sorted([r1, r2], key=default_sort_key), condition=condition) for (a, r1) in coeff_rv_list1 for (b, r2) in coeff_rv_list2] return Add.fromiter(addends) @classmethod def _expand_single_argument(cls, expr): # return (coefficient, random_symbol) pairs: if isinstance(expr, RandomSymbol): return [(S.One, expr)] elif isinstance(expr, Add): outval = [] for a in expr.args: if isinstance(a, Mul): outval.append(cls._get_mul_nonrv_rv_tuple(a)) elif is_random(a): outval.append((S.One, a)) return outval elif isinstance(expr, Mul): return [cls._get_mul_nonrv_rv_tuple(expr)] elif is_random(expr): return [(S.One, expr)] @classmethod def _get_mul_nonrv_rv_tuple(cls, m): rv = [] nonrv = [] for a in m.args: if is_random(a): rv.append(a) else: nonrv.append(a) return (Mul.fromiter(nonrv), Mul.fromiter(rv)) def _eval_rewrite_as_Expectation(self, arg1, arg2, condition=None, **kwargs): e1 = Expectation(arg1*arg2, condition) e2 = Expectation(arg1, condition)*Expectation(arg2, condition) return e1 - e2 def _eval_rewrite_as_Probability(self, arg1, arg2, condition=None, **kwargs): return self.rewrite(Expectation).rewrite(Probability) def _eval_rewrite_as_Integral(self, arg1, arg2, condition=None, **kwargs): return covariance(self.args[0], self.args[1], self._condition, evaluate=False) _eval_rewrite_as_Sum = _eval_rewrite_as_Integral def evaluate_integral(self): return self.rewrite(Integral).doit() class Moment(Expr): """ Symbolic class for Moment Examples ======== >>> from sympy import Symbol, Integral >>> from sympy.stats import Normal, Expectation, Probability, Moment >>> mu = Symbol('mu', real=True) >>> sigma = Symbol('sigma', real=True, positive=True) >>> X = Normal('X', mu, sigma) >>> M = Moment(X, 3, 1) To evaluate the result of Moment use `doit`: >>> M.doit() mu**3 - 3*mu**2 + 3*mu*sigma**2 + 3*mu - 3*sigma**2 - 1 Rewrite the Moment expression in terms of Expectation: >>> M.rewrite(Expectation) Expectation((X - 1)**3) Rewrite the Moment expression in terms of Probability: >>> M.rewrite(Probability) Integral((x - 1)**3*Probability(Eq(X, x)), (x, -oo, oo)) Rewrite the Moment expression in terms of Integral: >>> M.rewrite(Integral) Integral(sqrt(2)*(X - 1)**3*exp(-(X - mu)**2/(2*sigma**2))/(2*sqrt(pi)*sigma), (X, -oo, oo)) """ def __new__(cls, X, n, c=0, condition=None, **kwargs): X = _sympify(X) n = _sympify(n) c = _sympify(c) if condition is not None: condition = _sympify(condition) return super().__new__(cls, X, n, c, condition) else: return super().__new__(cls, X, n, c) def doit(self, **hints): if not is_random(self.args[0]): return self.args[0] return self.rewrite(Expectation).doit(**hints) def _eval_rewrite_as_Expectation(self, X, n, c=0, condition=None, **kwargs): return Expectation((X - c)**n, condition) def _eval_rewrite_as_Probability(self, X, n, c=0, condition=None, **kwargs): return self.rewrite(Expectation).rewrite(Probability) def _eval_rewrite_as_Integral(self, X, n, c=0, condition=None, **kwargs): return self.rewrite(Expectation).rewrite(Integral) class CentralMoment(Expr): """ Symbolic class Central Moment Examples ======== >>> from sympy import Symbol, Integral >>> from sympy.stats import Normal, Expectation, Probability, CentralMoment >>> mu = Symbol('mu', real=True) >>> sigma = Symbol('sigma', real=True, positive=True) >>> X = Normal('X', mu, sigma) >>> CM = CentralMoment(X, 4) To evaluate the result of CentralMoment use `doit`: >>> CM.doit().simplify() 3*sigma**4 Rewrite the CentralMoment expression in terms of Expectation: >>> CM.rewrite(Expectation) Expectation((X - Expectation(X))**4) Rewrite the CentralMoment expression in terms of Probability: >>> CM.rewrite(Probability) Integral((x - Integral(x*Probability(True), (x, -oo, oo)))**4*Probability(Eq(X, x)), (x, -oo, oo)) Rewrite the CentralMoment expression in terms of Integral: >>> CM.rewrite(Integral) Integral(sqrt(2)*(X - Integral(sqrt(2)*X*exp(-(X - mu)**2/(2*sigma**2))/(2*sqrt(pi)*sigma), (X, -oo, oo)))**4*exp(-(X - mu)**2/(2*sigma**2))/(2*sqrt(pi)*sigma), (X, -oo, oo)) """ def __new__(cls, X, n, condition=None, **kwargs): X = _sympify(X) n = _sympify(n) if condition is not None: condition = _sympify(condition) return super().__new__(cls, X, n, condition) else: return super().__new__(cls, X, n) def doit(self, **hints): if not is_random(self.args[0]): return self.args[0] return self.rewrite(Expectation).doit(**hints) def _eval_rewrite_as_Expectation(self, X, n, condition=None, **kwargs): mu = Expectation(X, condition, **kwargs) return Moment(X, n, mu, condition, **kwargs).rewrite(Expectation) def _eval_rewrite_as_Probability(self, X, n, condition=None, **kwargs): return self.rewrite(Expectation).rewrite(Probability) def _eval_rewrite_as_Integral(self, X, n, condition=None, **kwargs): return self.rewrite(Expectation).rewrite(Integral)
eedba592ddc25699c366bc4cd6585366004549aa6ea2cce70b6d8f02c21e283f
from sympy.ntheory import sieve, isprime from sympy.core.power import integer_log from sympy.core.compatibility import as_int import random rgen = random.Random() #----------------------------------------------------------------------------# # # # Lenstra's Elliptic Curve Factorization # # # #----------------------------------------------------------------------------# class Point: """Montgomery form of Points in an elliptic curve. In this form, the addition and doubling of points does not need any y-coordinate information thus decreasing the number of operations. Using Montgomery form we try to perform point addition and doubling in least amount of multiplications. The elliptic curve used here is of the form (E : b*y**2*z = x**3 + a*x**2*z + x*z**2). The a_24 parameter is equal to (a + 2)/4. References ========== .. [1] http://www.hyperelliptic.org/tanja/SHARCS/talks06/Gaj.pdf """ def __init__(self, x_cord, z_cord, a_24, mod): """ Initial parameters for the Point class. Parameters ========== x_cord : X coordinate of the Point z_cord : Z coordinate of the Point a_24 : Parameter of the elliptic curve in Montgomery form mod : modulus """ self.x_cord = x_cord self.z_cord = z_cord self.a_24 = a_24 self.mod = mod def __eq__(self, other): """Two points are equal if X/Z of both points are equal """ from sympy import mod_inverse if self.a_24 != other.a_24 or self.mod != other.mod: return False return self.x_cord * mod_inverse(self.z_cord, self.mod) % self.mod ==\ other.x_cord * mod_inverse(other.z_cord, self.mod) % self.mod def add(self, Q, diff): """ Add two points self and Q where diff = self - Q. Moreover the assumption is self.x_cord*Q.x_cord*(self.x_cord - Q.x_cord) != 0. This algorithm requires 6 multiplications. Here the difference between the points is already known and using this algorihtm speeds up the addition by reducing the number of multiplication required. Also in the mont_ladder algorithm is constructed in a way so that the difference between intermediate points is always equal to the initial point. So, we always know what the difference between the point is. Parameters ========== Q : point on the curve in Montgomery form diff : self - Q Examples ======== >>> from sympy.ntheory.ecm import Point >>> p1 = Point(11, 16, 7, 29) >>> p2 = Point(13, 10, 7, 29) >>> p3 = p2.add(p1, p1) >>> p3.x_cord 23 >>> p3.z_cord 17 """ u = (self.x_cord - self.z_cord)*(Q.x_cord + Q.z_cord) v = (self.x_cord + self.z_cord)*(Q.x_cord - Q.z_cord) add, subt = u + v, u - v x_cord = diff.z_cord * add * add % self.mod z_cord = diff.x_cord * subt * subt % self.mod return Point(x_cord, z_cord, self.a_24, self.mod) def double(self): """ Doubles a point in an elliptic curve in Montgomery form. This algorithm requires 5 multiplications. Examples ======== >>> from sympy.ntheory.ecm import Point >>> p1 = Point(11, 16, 7, 29) >>> p2 = p1.double() >>> p2.x_cord 13 >>> p2.z_cord 10 """ u, v = self.x_cord + self.z_cord, self.x_cord - self.z_cord u, v = u*u, v*v diff = u - v x_cord = u*v % self.mod z_cord = diff*(v + self.a_24*diff) % self.mod return Point(x_cord, z_cord, self.a_24, self.mod) def mont_ladder(self, k): """ Scalar multiplication of a point in Montgomery form using Montgomery Ladder Algorithm. A total of 11 multiplications are required in each step of this algorithm. Parameters ========== k : The positive integer multiplier Examples ======== >>> from sympy.ntheory.ecm import Point >>> p1 = Point(11, 16, 7, 29) >>> p3 = p1.mont_ladder(3) >>> p3.x_cord 23 >>> p3.z_cord 17 """ Q = self R = self.double() for i in bin(k)[3:]: if i == '1': Q = R.add(Q, self) R = R.double() else: R = Q.add(R, self) Q = Q.double() return Q def _ecm_one_factor(n, B1=10000, B2=100000, max_curve=200): """Returns one factor of n using Lenstra's 2 Stage Elliptic curve Factorization with Suyama's Parameterization. Here Montgomery arithmetic is used for fast computation of addition and doubling of points in elliptic curve. This ECM method considers elliptic curves in Montgomery form (E : b*y**2*z = x**3 + a*x**2*z + x*z**2) and involves elliptic curve operations (mod N), where the elements in Z are reduced (mod N). Since N is not a prime, E over FF(N) is not really an elliptic curve but we can still do point additions and doubling as if FF(N) was a field. Stage 1 : The basic algorithm involves taking a random point (P) on an elliptic curve in FF(N). The compute k*P using Montgomery ladder algorithm. Let q be an unknown factor of N. Then the order of the curve E, |E(FF(q))|, might be a smooth number that divides k. Then we have k = l * |E(FF(q))| for some l. For any point belonging to the curve E, |E(FF(q))|*P = O, hence k*P = l*|E(FF(q))|*P. Thus kP.z_cord = 0 (mod q), and the unknownn factor of N (q) can be recovered by taking gcd(kP.z_cord, N). Stage 2 : This is a continuation of Stage 1 if k*P != O. The idea utilize the fact that even if kP != 0, the value of k might miss just one large prime divisor of |E(FF(q))|. In this case we only need to compute the scalar multiplication by p to get p*k*P = O. Here a second bound B2 restrict the size of possible values of p. Parameters ========== n : Number to be Factored B1 : Stage 1 Bound B2 : Stage 2 Bound max_curve : Maximum number of curves generated References ========== .. [1] Carl Pomerance and Richard Crandall "Prime Numbers: A Computational Perspective" (2nd Ed.), page 344 """ from sympy import gcd, mod_inverse, sqrt n = as_int(n) if B1 % 2 != 0 or B2 % 2 != 0: raise ValueError("The Bounds should be an even integer") sieve.extend(B2) if isprime(n): return n curve = 0 D = int(sqrt(B2)) beta = [0]*(D + 1) S = [0]*(D + 1) k = 1 for p in sieve.primerange(1, B1 + 1): k *= pow(p, integer_log(B1, p)[0]) while(curve <= max_curve): curve += 1 #Suyama's Paramatrization sigma = rgen.randint(6, n - 1) u = (sigma*sigma - 5) % n v = (4*sigma) % n diff = v - u u_3 = pow(u, 3, n) try: C = (pow(diff, 3, n)*(3*u + v)*mod_inverse(4*u_3*v, n) - 2) % n except ValueError: #If the mod_inverse(4*u_3*v, n) doesn't exist return gcd(4*u_3*v, n) a24 = (C + 2)*mod_inverse(4, n) % n Q = Point(u_3 , pow(v, 3, n), a24, n) Q = Q.mont_ladder(k) g = gcd(Q.z_cord, n) #Stage 1 factor if g != 1 and g != n: return g #Stage 1 failure. Q.z = 0, Try another curve elif g == n: continue #Stage 2 - Improved Standard Continuation S[1] = Q.double() S[2] = S[1].double() beta[1] = (S[1].x_cord*S[1].z_cord) % n beta[2] = (S[2].x_cord*S[2].z_cord) % n for d in range(3, D + 1): S[d] = S[d - 1].add(S[1], S[d - 2]) beta[d] = (S[d].x_cord*S[d].z_cord) % n g = 1 B = B1 - 1 T = Q.mont_ladder(B - 2*D) R = Q.mont_ladder(B) for r in range(B, B2, 2*D): alpha = (R.x_cord*R.z_cord) % n for q in sieve.primerange(r + 2, r + 2*D + 1): delta = (q - r) // 2 f = (R.x_cord - S[d].x_cord)*(R.z_cord + S[d].z_cord) -\ alpha + beta[delta] g = (g*f) % n #Swap T, R = R, R.add(S[D], T) g = gcd(n, g) #Stage 2 Factor found if g != 1 and g != n: return g #ECM failed, Increase the bounds raise ValueError("Increase the bounds") def ecm(n, B1=10000, B2=100000, max_curve=200, seed=1234): """Performs factorization using Lenstra's Elliptic curve method. This function repeatedly calls `ecm_one_factor` to compute the factors of n. First all the small factors are taken out using trial division. Then `ecm_one_factor` is used to compute one factor at a time. Parameters ========== n : Number to be Factored B1 : Stage 1 Bound B2 : Stage 2 Bound max_curve : Maximum number of curves generated seed : Initialize pseudorandom generator Examples ======== >>> from sympy.ntheory import ecm >>> ecm(25645121643901801) {5394769, 4753701529} >>> ecm(9804659461513846513) {4641991, 2112166839943} """ _factors = set() for prime in sieve.primerange(1, 100000): if n % prime == 0: _factors.add(prime) while(n % prime == 0): n //= prime rgen.seed(seed) while(n > 1): try: factor = _ecm_one_factor(n, B1, B2, max_curve) except ValueError: raise ValueError("Increase the bounds") _factors.add(factor) n //= factor factors = set() for factor in _factors: if isprime(factor): factors.add(factor) continue factors |= ecm(factor) return factors
9db508dc1c221c18a05805764cb0189124d0a3287cb6791790a561839e9919bc
""" Primality testing """ from sympy.core.compatibility import as_int from mpmath.libmp import bitcount as _bitlength def _int_tuple(*i): return tuple(int(_) for _ in i) def is_euler_pseudoprime(n, b): """Returns True if n is prime or an Euler pseudoprime to base b, else False. Euler Pseudoprime : In arithmetic, an odd composite integer n is called an euler pseudoprime to base a, if a and n are coprime and satisfy the modular arithmetic congruence relation : a ^ (n-1)/2 = + 1(mod n) or a ^ (n-1)/2 = - 1(mod n) (where mod refers to the modulo operation). Examples ======== >>> from sympy.ntheory.primetest import is_euler_pseudoprime >>> is_euler_pseudoprime(2, 5) True References ========== .. [1] https://en.wikipedia.org/wiki/Euler_pseudoprime """ from sympy.ntheory.factor_ import trailing if not mr(n, [b]): return False n = as_int(n) r = n - 1 c = pow(b, r >> trailing(r), n) if c == 1: return True while True: if c == n - 1: return True c = pow(c, 2, n) if c == 1: return False def is_square(n, prep=True): """Return True if n == a * a for some integer a, else False. If n is suspected of *not* being a square then this is a quick method of confirming that it is not. Examples ======== >>> from sympy.ntheory.primetest import is_square >>> is_square(25) True >>> is_square(2) False References ========== [1] http://mersenneforum.org/showpost.php?p=110896 See Also ======== sympy.core.power.integer_nthroot """ if prep: n = as_int(n) if n < 0: return False if n in [0, 1]: return True m = n & 127 if not ((m*0x8bc40d7d) & (m*0xa1e2f5d1) & 0x14020a): m = n % 63 if not ((m*0x3d491df7) & (m*0xc824a9f9) & 0x10f14008): from sympy.core.power import integer_nthroot return integer_nthroot(n, 2)[1] return False def _test(n, base, s, t): """Miller-Rabin strong pseudoprime test for one base. Return False if n is definitely composite, True if n is probably prime, with a probability greater than 3/4. """ # do the Fermat test b = pow(base, t, n) if b == 1 or b == n - 1: return True else: for j in range(1, s): b = pow(b, 2, n) if b == n - 1: return True # see I. Niven et al. "An Introduction to Theory of Numbers", page 78 if b == 1: return False return False def mr(n, bases): """Perform a Miller-Rabin strong pseudoprime test on n using a given list of bases/witnesses. References ========== - Richard Crandall & Carl Pomerance (2005), "Prime Numbers: A Computational Perspective", Springer, 2nd edition, 135-138 A list of thresholds and the bases they require are here: https://en.wikipedia.org/wiki/Miller%E2%80%93Rabin_primality_test#Deterministic_variants Examples ======== >>> from sympy.ntheory.primetest import mr >>> mr(1373651, [2, 3]) False >>> mr(479001599, [31, 73]) True """ from sympy.ntheory.factor_ import trailing from sympy.polys.domains import ZZ n = as_int(n) if n < 2: return False # remove powers of 2 from n-1 (= t * 2**s) s = trailing(n - 1) t = n >> s for base in bases: # Bases >= n are wrapped, bases < 2 are invalid if base >= n: base %= n if base >= 2: base = ZZ(base) if not _test(n, base, s, t): return False return True def _lucas_sequence(n, P, Q, k): """Return the modular Lucas sequence (U_k, V_k, Q_k). Given a Lucas sequence defined by P, Q, returns the kth values for U and V, along with Q^k, all modulo n. This is intended for use with possibly very large values of n and k, where the combinatorial functions would be completely unusable. The modular Lucas sequences are used in numerous places in number theory, especially in the Lucas compositeness tests and the various n + 1 proofs. Examples ======== >>> from sympy.ntheory.primetest import _lucas_sequence >>> N = 10**2000 + 4561 >>> sol = U, V, Qk = _lucas_sequence(N, 3, 1, N//2); sol (0, 2, 1) """ D = P*P - 4*Q if n < 2: raise ValueError("n must be >= 2") if k < 0: raise ValueError("k must be >= 0") if D == 0: raise ValueError("D must not be zero") if k == 0: return _int_tuple(0, 2, Q) U = 1 V = P Qk = Q b = _bitlength(k) if Q == 1: # Optimization for extra strong tests. while b > 1: U = (U*V) % n V = (V*V - 2) % n b -= 1 if (k >> (b - 1)) & 1: U, V = U*P + V, V*P + U*D if U & 1: U += n if V & 1: V += n U, V = U >> 1, V >> 1 elif P == 1 and Q == -1: # Small optimization for 50% of Selfridge parameters. while b > 1: U = (U*V) % n if Qk == 1: V = (V*V - 2) % n else: V = (V*V + 2) % n Qk = 1 b -= 1 if (k >> (b-1)) & 1: U, V = U + V, V + U*D if U & 1: U += n if V & 1: V += n U, V = U >> 1, V >> 1 Qk = -1 else: # The general case with any P and Q. while b > 1: U = (U*V) % n V = (V*V - 2*Qk) % n Qk *= Qk b -= 1 if (k >> (b - 1)) & 1: U, V = U*P + V, V*P + U*D if U & 1: U += n if V & 1: V += n U, V = U >> 1, V >> 1 Qk *= Q Qk %= n return _int_tuple(U % n, V % n, Qk) def _lucas_selfridge_params(n): """Calculates the Selfridge parameters (D, P, Q) for n. This is method A from page 1401 of Baillie and Wagstaff. References ========== - "Lucas Pseudoprimes", Baillie and Wagstaff, 1980. http://mpqs.free.fr/LucasPseudoprimes.pdf """ from sympy.core import igcd from sympy.ntheory.residue_ntheory import jacobi_symbol D = 5 while True: g = igcd(abs(D), n) if g > 1 and g != n: return (0, 0, 0) if jacobi_symbol(D, n) == -1: break if D > 0: D = -D - 2 else: D = -D + 2 return _int_tuple(D, 1, (1 - D)/4) def _lucas_extrastrong_params(n): """Calculates the "extra strong" parameters (D, P, Q) for n. References ========== - OEIS A217719: Extra Strong Lucas Pseudoprimes https://oeis.org/A217719 - https://en.wikipedia.org/wiki/Lucas_pseudoprime """ from sympy.core import igcd from sympy.ntheory.residue_ntheory import jacobi_symbol P, Q, D = 3, 1, 5 while True: g = igcd(D, n) if g > 1 and g != n: return (0, 0, 0) if jacobi_symbol(D, n) == -1: break P += 1 D = P*P - 4 return _int_tuple(D, P, Q) def is_lucas_prp(n): """Standard Lucas compositeness test with Selfridge parameters. Returns False if n is definitely composite, and True if n is a Lucas probable prime. This is typically used in combination with the Miller-Rabin test. References ========== - "Lucas Pseudoprimes", Baillie and Wagstaff, 1980. http://mpqs.free.fr/LucasPseudoprimes.pdf - OEIS A217120: Lucas Pseudoprimes https://oeis.org/A217120 - https://en.wikipedia.org/wiki/Lucas_pseudoprime Examples ======== >>> from sympy.ntheory.primetest import isprime, is_lucas_prp >>> for i in range(10000): ... if is_lucas_prp(i) and not isprime(i): ... print(i) 323 377 1159 1829 3827 5459 5777 9071 9179 """ n = as_int(n) if n == 2: return True if n < 2 or (n % 2) == 0: return False if is_square(n, False): return False D, P, Q = _lucas_selfridge_params(n) if D == 0: return False U, V, Qk = _lucas_sequence(n, P, Q, n+1) return U == 0 def is_strong_lucas_prp(n): """Strong Lucas compositeness test with Selfridge parameters. Returns False if n is definitely composite, and True if n is a strong Lucas probable prime. This is often used in combination with the Miller-Rabin test, and in particular, when combined with M-R base 2 creates the strong BPSW test. References ========== - "Lucas Pseudoprimes", Baillie and Wagstaff, 1980. http://mpqs.free.fr/LucasPseudoprimes.pdf - OEIS A217255: Strong Lucas Pseudoprimes https://oeis.org/A217255 - https://en.wikipedia.org/wiki/Lucas_pseudoprime - https://en.wikipedia.org/wiki/Baillie-PSW_primality_test Examples ======== >>> from sympy.ntheory.primetest import isprime, is_strong_lucas_prp >>> for i in range(20000): ... if is_strong_lucas_prp(i) and not isprime(i): ... print(i) 5459 5777 10877 16109 18971 """ from sympy.ntheory.factor_ import trailing n = as_int(n) if n == 2: return True if n < 2 or (n % 2) == 0: return False if is_square(n, False): return False D, P, Q = _lucas_selfridge_params(n) if D == 0: return False # remove powers of 2 from n+1 (= k * 2**s) s = trailing(n + 1) k = (n+1) >> s U, V, Qk = _lucas_sequence(n, P, Q, k) if U == 0 or V == 0: return True for r in range(1, s): V = (V*V - 2*Qk) % n if V == 0: return True Qk = pow(Qk, 2, n) return False def is_extra_strong_lucas_prp(n): """Extra Strong Lucas compositeness test. Returns False if n is definitely composite, and True if n is a "extra strong" Lucas probable prime. The parameters are selected using P = 3, Q = 1, then incrementing P until (D|n) == -1. The test itself is as defined in Grantham 2000, from the Mo and Jones preprint. The parameter selection and test are the same as used in OEIS A217719, Perl's Math::Prime::Util, and the Lucas pseudoprime page on Wikipedia. With these parameters, there are no counterexamples below 2^64 nor any known above that range. It is 20-50% faster than the strong test. Because of the different parameters selected, there is no relationship between the strong Lucas pseudoprimes and extra strong Lucas pseudoprimes. In particular, one is not a subset of the other. References ========== - "Frobenius Pseudoprimes", Jon Grantham, 2000. http://www.ams.org/journals/mcom/2001-70-234/S0025-5718-00-01197-2/ - OEIS A217719: Extra Strong Lucas Pseudoprimes https://oeis.org/A217719 - https://en.wikipedia.org/wiki/Lucas_pseudoprime Examples ======== >>> from sympy.ntheory.primetest import isprime, is_extra_strong_lucas_prp >>> for i in range(20000): ... if is_extra_strong_lucas_prp(i) and not isprime(i): ... print(i) 989 3239 5777 10877 """ # Implementation notes: # 1) the parameters differ from Thomas R. Nicely's. His parameter # selection leads to pseudoprimes that overlap M-R tests, and # contradict Baillie and Wagstaff's suggestion of (D|n) = -1. # 2) The MathWorld page as of June 2013 specifies Q=-1. The Lucas # sequence must have Q=1. See Grantham theorem 2.3, any of the # references on the MathWorld page, or run it and see Q=-1 is wrong. from sympy.ntheory.factor_ import trailing n = as_int(n) if n == 2: return True if n < 2 or (n % 2) == 0: return False if is_square(n, False): return False D, P, Q = _lucas_extrastrong_params(n) if D == 0: return False # remove powers of 2 from n+1 (= k * 2**s) s = trailing(n + 1) k = (n+1) >> s U, V, Qk = _lucas_sequence(n, P, Q, k) if U == 0 and (V == 2 or V == n - 2): return True for r in range(1, s): if V == 0: return True V = (V*V - 2) % n return False def isprime(n): """ Test if n is a prime number (True) or not (False). For n < 2^64 the answer is definitive; larger n values have a small probability of actually being pseudoprimes. Negative numbers (e.g. -2) are not considered prime. The first step is looking for trivial factors, which if found enables a quick return. Next, if the sieve is large enough, use bisection search on the sieve. For small numbers, a set of deterministic Miller-Rabin tests are performed with bases that are known to have no counterexamples in their range. Finally if the number is larger than 2^64, a strong BPSW test is performed. While this is a probable prime test and we believe counterexamples exist, there are no known counterexamples. Examples ======== >>> from sympy.ntheory import isprime >>> isprime(13) True >>> isprime(13.0) # limited precision False >>> isprime(15) False Notes ===== This routine is intended only for integer input, not numerical expressions which may represent numbers. Floats are also rejected as input because they represent numbers of limited precision. While it is tempting to permit 7.0 to represent an integer there are errors that may "pass silently" if this is allowed: >>> from sympy import Float, S >>> int(1e3) == 1e3 == 10**3 True >>> int(1e23) == 1e23 True >>> int(1e23) == 10**23 False >>> near_int = 1 + S(1)/10**19 >>> near_int == int(near_int) False >>> n = Float(near_int, 10) # truncated by precision >>> n == int(n) True >>> n = Float(near_int, 20) >>> n == int(n) False See Also ======== sympy.ntheory.generate.primerange : Generates all primes in a given range sympy.ntheory.generate.primepi : Return the number of primes less than or equal to n sympy.ntheory.generate.prime : Return the nth prime References ========== - https://en.wikipedia.org/wiki/Strong_pseudoprime - "Lucas Pseudoprimes", Baillie and Wagstaff, 1980. http://mpqs.free.fr/LucasPseudoprimes.pdf - https://en.wikipedia.org/wiki/Baillie-PSW_primality_test """ try: n = as_int(n) except ValueError: return False # Step 1, do quick composite testing via trial division. The individual # modulo tests benchmark faster than one or two primorial igcds for me. # The point here is just to speedily handle small numbers and many # composites. Step 2 only requires that n <= 2 get handled here. if n in [2, 3, 5]: return True if n < 2 or (n % 2) == 0 or (n % 3) == 0 or (n % 5) == 0: return False if n < 49: return True if (n % 7) == 0 or (n % 11) == 0 or (n % 13) == 0 or (n % 17) == 0 or \ (n % 19) == 0 or (n % 23) == 0 or (n % 29) == 0 or (n % 31) == 0 or \ (n % 37) == 0 or (n % 41) == 0 or (n % 43) == 0 or (n % 47) == 0: return False if n < 2809: return True if n <= 23001: return pow(2, n, n) == 2 and n not in [7957, 8321, 13747, 18721, 19951] # bisection search on the sieve if the sieve is large enough from sympy.ntheory.generate import sieve as s if n <= s._list[-1]: l, u = s.search(n) return l == u # If we have GMPY2, skip straight to step 3 and do a strong BPSW test. # This should be a bit faster than our step 2, and for large values will # be a lot faster than our step 3 (C+GMP vs. Python). from sympy.core.compatibility import HAS_GMPY if HAS_GMPY == 2: from gmpy2 import is_strong_prp, is_strong_selfridge_prp return is_strong_prp(n, 2) and is_strong_selfridge_prp(n) # Step 2: deterministic Miller-Rabin testing for numbers < 2^64. See: # https://miller-rabin.appspot.com/ # for lists. We have made sure the M-R routine will successfully handle # bases larger than n, so we can use the minimal set. if n < 341531: return mr(n, [9345883071009581737]) if n < 885594169: return mr(n, [725270293939359937, 3569819667048198375]) if n < 350269456337: return mr(n, [4230279247111683200, 14694767155120705706, 16641139526367750375]) if n < 55245642489451: return mr(n, [2, 141889084524735, 1199124725622454117, 11096072698276303650]) if n < 7999252175582851: return mr(n, [2, 4130806001517, 149795463772692060, 186635894390467037, 3967304179347715805]) if n < 585226005592931977: return mr(n, [2, 123635709730000, 9233062284813009, 43835965440333360, 761179012939631437, 1263739024124850375]) if n < 18446744073709551616: return mr(n, [2, 325, 9375, 28178, 450775, 9780504, 1795265022]) # We could do this instead at any point: #if n < 18446744073709551616: # return mr(n, [2]) and is_extra_strong_lucas_prp(n) # Here are tests that are safe for MR routines that don't understand # large bases. #if n < 9080191: # return mr(n, [31, 73]) #if n < 19471033: # return mr(n, [2, 299417]) #if n < 38010307: # return mr(n, [2, 9332593]) #if n < 316349281: # return mr(n, [11000544, 31481107]) #if n < 4759123141: # return mr(n, [2, 7, 61]) #if n < 105936894253: # return mr(n, [2, 1005905886, 1340600841]) #if n < 31858317218647: # return mr(n, [2, 642735, 553174392, 3046413974]) #if n < 3071837692357849: # return mr(n, [2, 75088, 642735, 203659041, 3613982119]) #if n < 18446744073709551616: # return mr(n, [2, 325, 9375, 28178, 450775, 9780504, 1795265022]) # Step 3: BPSW. # # Time for isprime(10**2000 + 4561), no gmpy or gmpy2 installed # 44.0s old isprime using 46 bases # 5.3s strong BPSW + one random base # 4.3s extra strong BPSW + one random base # 4.1s strong BPSW # 3.2s extra strong BPSW # Classic BPSW from page 1401 of the paper. See alternate ideas below. return mr(n, [2]) and is_strong_lucas_prp(n) # Using extra strong test, which is somewhat faster #return mr(n, [2]) and is_extra_strong_lucas_prp(n) # Add a random M-R base #import random #return mr(n, [2, random.randint(3, n-1)]) and is_strong_lucas_prp(n) def is_gaussian_prime(num): r"""Test if num is a Gaussian prime number. References ========== .. [1] https://oeis.org/wiki/Gaussian_primes """ from sympy import sympify num = sympify(num) a, b = num.as_real_imag() a = as_int(a, strict=False) b = as_int(b, strict=False) if a == 0: b = abs(b) return isprime(b) and b % 4 == 3 elif b == 0: a = abs(a) return isprime(a) and a % 4 == 3 return isprime(a**2 + b**2)
5dda2069b63640692c8b3ec24c1b028d7f739f72a967af3371c8881910d5082c
from sympy import Integer, Rational, Tuple import sympy.polys from math import gcd def egyptian_fraction(r, algorithm="Greedy"): """ Return the list of denominators of an Egyptian fraction expansion [1]_ of the said rational `r`. Parameters ========== r : Rational or (p, q) a positive rational number, ``p/q``. algorithm : { "Greedy", "Graham Jewett", "Takenouchi", "Golomb" }, optional Denotes the algorithm to be used (the default is "Greedy"). Examples ======== >>> from sympy import Rational >>> from sympy.ntheory.egyptian_fraction import egyptian_fraction >>> egyptian_fraction(Rational(3, 7)) [3, 11, 231] >>> egyptian_fraction((3, 7), "Graham Jewett") [7, 8, 9, 56, 57, 72, 3192] >>> egyptian_fraction((3, 7), "Takenouchi") [4, 7, 28] >>> egyptian_fraction((3, 7), "Golomb") [3, 15, 35] >>> egyptian_fraction((11, 5), "Golomb") [1, 2, 3, 4, 9, 234, 1118, 2580] See Also ======== sympy.core.numbers.Rational Notes ===== Currently the following algorithms are supported: 1) Greedy Algorithm Also called the Fibonacci-Sylvester algorithm [2]_. At each step, extract the largest unit fraction less than the target and replace the target with the remainder. It has some distinct properties: a) Given `p/q` in lowest terms, generates an expansion of maximum length `p`. Even as the numerators get large, the number of terms is seldom more than a handful. b) Uses minimal memory. c) The terms can blow up (standard examples of this are 5/121 and 31/311). The denominator is at most squared at each step (doubly-exponential growth) and typically exhibits singly-exponential growth. 2) Graham Jewett Algorithm The algorithm suggested by the result of Graham and Jewett. Note that this has a tendency to blow up: the length of the resulting expansion is always ``2**(x/gcd(x, y)) - 1``. See [3]_. 3) Takenouchi Algorithm The algorithm suggested by Takenouchi (1921). Differs from the Graham-Jewett algorithm only in the handling of duplicates. See [3]_. 4) Golomb's Algorithm A method given by Golumb (1962), using modular arithmetic and inverses. It yields the same results as a method using continued fractions proposed by Bleicher (1972). See [4]_. If the given rational is greater than or equal to 1, a greedy algorithm of summing the harmonic sequence 1/1 + 1/2 + 1/3 + ... is used, taking all the unit fractions of this sequence until adding one more would be greater than the given number. This list of denominators is prefixed to the result from the requested algorithm used on the remainder. For example, if r is 8/3, using the Greedy algorithm, we get [1, 2, 3, 4, 5, 6, 7, 14, 420], where the beginning of the sequence, [1, 2, 3, 4, 5, 6, 7] is part of the harmonic sequence summing to 363/140, leaving a remainder of 31/420, which yields [14, 420] by the Greedy algorithm. The result of egyptian_fraction(Rational(8, 3), "Golomb") is [1, 2, 3, 4, 5, 6, 7, 14, 574, 2788, 6460, 11590, 33062, 113820], and so on. References ========== .. [1] https://en.wikipedia.org/wiki/Egyptian_fraction .. [2] https://en.wikipedia.org/wiki/Greedy_algorithm_for_Egyptian_fractions .. [3] https://www.ics.uci.edu/~eppstein/numth/egypt/conflict.html .. [4] http://ami.ektf.hu/uploads/papers/finalpdf/AMI_42_from129to134.pdf """ if not isinstance(r, Rational): if isinstance(r, (Tuple, tuple)) and len(r) == 2: r = Rational(*r) else: raise ValueError("Value must be a Rational or tuple of ints") if r <= 0: raise ValueError("Value must be positive") # common cases that all methods agree on x, y = r.as_numer_denom() if y == 1 and x == 2: return [Integer(i) for i in [1, 2, 3, 6]] if x == y + 1: return [Integer(1), y] prefix, rem = egypt_harmonic(r) if rem == 0: return prefix # work in python ints x, y = rem.p, rem.q # assert x < y and gcd(x, y) = 1 if algorithm == "Greedy": postfix = egypt_greedy(x, y) elif algorithm == "Graham Jewett": postfix = egypt_graham_jewett(x, y) elif algorithm == "Takenouchi": postfix = egypt_takenouchi(x, y) elif algorithm == "Golomb": postfix = egypt_golomb(x, y) else: raise ValueError("Entered invalid algorithm") return prefix + [Integer(i) for i in postfix] def egypt_greedy(x, y): # assumes gcd(x, y) == 1 if x == 1: return [y] else: a = (-y) % x b = y*(y//x + 1) c = gcd(a, b) if c > 1: num, denom = a//c, b//c else: num, denom = a, b return [y//x + 1] + egypt_greedy(num, denom) def egypt_graham_jewett(x, y): # assumes gcd(x, y) == 1 l = [y] * x # l is now a list of integers whose reciprocals sum to x/y. # we shall now proceed to manipulate the elements of l without # changing the reciprocated sum until all elements are unique. while len(l) != len(set(l)): l.sort() # so the list has duplicates. find a smallest pair for i in range(len(l) - 1): if l[i] == l[i + 1]: break # we have now identified a pair of identical # elements: l[i] and l[i + 1]. # now comes the application of the result of graham and jewett: l[i + 1] = l[i] + 1 # and we just iterate that until the list has no duplicates. l.append(l[i]*(l[i] + 1)) return sorted(l) def egypt_takenouchi(x, y): # assumes gcd(x, y) == 1 # special cases for 3/y if x == 3: if y % 2 == 0: return [y//2, y] i = (y - 1)//2 j = i + 1 k = j + i return [j, k, j*k] l = [y] * x while len(l) != len(set(l)): l.sort() for i in range(len(l) - 1): if l[i] == l[i + 1]: break k = l[i] if k % 2 == 0: l[i] = l[i] // 2 del l[i + 1] else: l[i], l[i + 1] = (k + 1)//2, k*(k + 1)//2 return sorted(l) def egypt_golomb(x, y): # assumes x < y and gcd(x, y) == 1 if x == 1: return [y] xp = sympy.polys.ZZ.invert(int(x), int(y)) rv = [xp*y] rv.extend(egypt_golomb((x*xp - 1)//y, xp)) return sorted(rv) def egypt_harmonic(r): # assumes r is Rational rv = [] d = Integer(1) acc = Integer(0) while acc + 1/d <= r: acc += 1/d rv.append(d) d += 1 return (rv, r - acc)
6be789fe450a7e3c843861386fb9b99c223c39629734db06498d3efb716b0399
from sympy.combinatorics.permutations import Permutation, _af_rmul, \ _af_invert, _af_new from sympy.combinatorics.perm_groups import PermutationGroup, _orbit, \ _orbit_transversal from sympy.combinatorics.util import _distribute_gens_by_base, \ _orbits_transversals_from_bsgs """ References for tensor canonicalization: [1] R. Portugal "Algorithmic simplification of tensor expressions", J. Phys. A 32 (1999) 7779-7789 [2] R. Portugal, B.F. Svaiter "Group-theoretic Approach for Symbolic Tensor Manipulation: I. Free Indices" arXiv:math-ph/0107031v1 [3] L.R.U. Manssur, R. Portugal "Group-theoretic Approach for Symbolic Tensor Manipulation: II. Dummy Indices" arXiv:math-ph/0107032v1 [4] xperm.c part of XPerm written by J. M. Martin-Garcia http://www.xact.es/index.html """ def dummy_sgs(dummies, sym, n): """ Return the strong generators for dummy indices. Parameters ========== dummies : List of dummy indices. `dummies[2k], dummies[2k+1]` are paired indices. In base form, the dummy indices are always in consecutive positions. sym : symmetry under interchange of contracted dummies:: * None no symmetry * 0 commuting * 1 anticommuting n : number of indices Examples ======== >>> from sympy.combinatorics.tensor_can import dummy_sgs >>> dummy_sgs(list(range(2, 8)), 0, 8) [[0, 1, 3, 2, 4, 5, 6, 7, 8, 9], [0, 1, 2, 3, 5, 4, 6, 7, 8, 9], [0, 1, 2, 3, 4, 5, 7, 6, 8, 9], [0, 1, 4, 5, 2, 3, 6, 7, 8, 9], [0, 1, 2, 3, 6, 7, 4, 5, 8, 9]] """ if len(dummies) > n: raise ValueError("List too large") res = [] # exchange of contravariant and covariant indices if sym is not None: for j in dummies[::2]: a = list(range(n + 2)) if sym == 1: a[n] = n + 1 a[n + 1] = n a[j], a[j + 1] = a[j + 1], a[j] res.append(a) # rename dummy indices for j in dummies[:-3:2]: a = list(range(n + 2)) a[j:j + 4] = a[j + 2], a[j + 3], a[j], a[j + 1] res.append(a) return res def _min_dummies(dummies, sym, indices): """ Return list of minima of the orbits of indices in group of dummies. See ``double_coset_can_rep`` for the description of ``dummies`` and ``sym``. ``indices`` is the initial list of dummy indices. Examples ======== >>> from sympy.combinatorics.tensor_can import _min_dummies >>> _min_dummies([list(range(2, 8))], [0], list(range(10))) [0, 1, 2, 2, 2, 2, 2, 2, 8, 9] """ num_types = len(sym) m = [] for dx in dummies: if dx: m.append(min(dx)) else: m.append(None) res = indices[:] for i in range(num_types): for c, i in enumerate(indices): for j in range(num_types): if i in dummies[j]: res[c] = m[j] break return res def _trace_S(s, j, b, S_cosets): """ Return the representative h satisfying s[h[b]] == j If there is not such a representative return None """ for h in S_cosets[b]: if s[h[b]] == j: return h return None def _trace_D(gj, p_i, Dxtrav): """ Return the representative h satisfying h[gj] == p_i If there is not such a representative return None """ for h in Dxtrav: if h[gj] == p_i: return h return None def _dumx_remove(dumx, dumx_flat, p0): """ remove p0 from dumx """ res = [] for dx in dumx: if p0 not in dx: res.append(dx) continue k = dx.index(p0) if k % 2 == 0: p0_paired = dx[k + 1] else: p0_paired = dx[k - 1] dx.remove(p0) dx.remove(p0_paired) dumx_flat.remove(p0) dumx_flat.remove(p0_paired) res.append(dx) def transversal2coset(size, base, transversal): a = [] j = 0 for i in range(size): if i in base: a.append(sorted(transversal[j].values())) j += 1 else: a.append([list(range(size))]) j = len(a) - 1 while a[j] == [list(range(size))]: j -= 1 return a[:j + 1] def double_coset_can_rep(dummies, sym, b_S, sgens, S_transversals, g): """ Butler-Portugal algorithm for tensor canonicalization with dummy indices. Parameters ========== dummies list of lists of dummy indices, one list for each type of index; the dummy indices are put in order contravariant, covariant [d0, -d0, d1, -d1, ...]. sym list of the symmetries of the index metric for each type. possible symmetries of the metrics * 0 symmetric * 1 antisymmetric * None no symmetry b_S base of a minimal slot symmetry BSGS. sgens generators of the slot symmetry BSGS. S_transversals transversals for the slot BSGS. g permutation representing the tensor. Returns ======= Return 0 if the tensor is zero, else return the array form of the permutation representing the canonical form of the tensor. Notes ===== A tensor with dummy indices can be represented in a number of equivalent ways which typically grows exponentially with the number of indices. To be able to establish if two tensors with many indices are equal becomes computationally very slow in absence of an efficient algorithm. The Butler-Portugal algorithm [3] is an efficient algorithm to put tensors in canonical form, solving the above problem. Portugal observed that a tensor can be represented by a permutation, and that the class of tensors equivalent to it under slot and dummy symmetries is equivalent to the double coset `D*g*S` (Note: in this documentation we use the conventions for multiplication of permutations p, q with (p*q)(i) = p[q[i]] which is opposite to the one used in the Permutation class) Using the algorithm by Butler to find a representative of the double coset one can find a canonical form for the tensor. To see this correspondence, let `g` be a permutation in array form; a tensor with indices `ind` (the indices including both the contravariant and the covariant ones) can be written as `t = T(ind[g[0]],..., ind[g[n-1]])`, where `n= len(ind)`; `g` has size `n + 2`, the last two indices for the sign of the tensor (trick introduced in [4]). A slot symmetry transformation `s` is a permutation acting on the slots `t -> T(ind[(g*s)[0]],..., ind[(g*s)[n-1]])` A dummy symmetry transformation acts on `ind` `t -> T(ind[(d*g)[0]],..., ind[(d*g)[n-1]])` Being interested only in the transformations of the tensor under these symmetries, one can represent the tensor by `g`, which transforms as `g -> d*g*s`, so it belongs to the coset `D*g*S`, or in other words to the set of all permutations allowed by the slot and dummy symmetries. Let us explain the conventions by an example. Given a tensor `T^{d3 d2 d1}{}_{d1 d2 d3}` with the slot symmetries `T^{a0 a1 a2 a3 a4 a5} = -T^{a2 a1 a0 a3 a4 a5}` `T^{a0 a1 a2 a3 a4 a5} = -T^{a4 a1 a2 a3 a0 a5}` and symmetric metric, find the tensor equivalent to it which is the lowest under the ordering of indices: lexicographic ordering `d1, d2, d3` and then contravariant before covariant index; that is the canonical form of the tensor. The canonical form is `-T^{d1 d2 d3}{}_{d1 d2 d3}` obtained using `T^{a0 a1 a2 a3 a4 a5} = -T^{a2 a1 a0 a3 a4 a5}`. To convert this problem in the input for this function, use the following ordering of the index names (- for covariant for short) `d1, -d1, d2, -d2, d3, -d3` `T^{d3 d2 d1}{}_{d1 d2 d3}` corresponds to `g = [4, 2, 0, 1, 3, 5, 6, 7]` where the last two indices are for the sign `sgens = [Permutation(0, 2)(6, 7), Permutation(0, 4)(6, 7)]` sgens[0] is the slot symmetry `-(0, 2)` `T^{a0 a1 a2 a3 a4 a5} = -T^{a2 a1 a0 a3 a4 a5}` sgens[1] is the slot symmetry `-(0, 4)` `T^{a0 a1 a2 a3 a4 a5} = -T^{a4 a1 a2 a3 a0 a5}` The dummy symmetry group D is generated by the strong base generators `[(0, 1), (2, 3), (4, 5), (0, 2)(1, 3), (0, 4)(1, 5)]` where the first three interchange covariant and contravariant positions of the same index (d1 <-> -d1) and the last two interchange the dummy indices themselves (d1 <-> d2). The dummy symmetry acts from the left `d = [1, 0, 2, 3, 4, 5, 6, 7]` exchange `d1 <-> -d1` `T^{d3 d2 d1}{}_{d1 d2 d3} == T^{d3 d2}{}_{d1}{}^{d1}{}_{d2 d3}` `g=[4, 2, 0, 1, 3, 5, 6, 7] -> [4, 2, 1, 0, 3, 5, 6, 7] = _af_rmul(d, g)` which differs from `_af_rmul(g, d)`. The slot symmetry acts from the right `s = [2, 1, 0, 3, 4, 5, 7, 6]` exchanges slots 0 and 2 and changes sign `T^{d3 d2 d1}{}_{d1 d2 d3} == -T^{d1 d2 d3}{}_{d1 d2 d3}` `g=[4,2,0,1,3,5,6,7] -> [0, 2, 4, 1, 3, 5, 7, 6] = _af_rmul(g, s)` Example in which the tensor is zero, same slot symmetries as above: `T^{d2}{}_{d1 d3}{}^{d1 d3}{}_{d2}` `= -T^{d3}{}_{d1 d3}{}^{d1 d2}{}_{d2}` under slot symmetry `-(0,4)`; `= T_{d3 d1}{}^{d3}{}^{d1 d2}{}_{d2}` under slot symmetry `-(0,2)`; `= T^{d3}{}_{d1 d3}{}^{d1 d2}{}_{d2}` symmetric metric; `= 0` since two of these lines have tensors differ only for the sign. The double coset D*g*S consists of permutations `h = d*g*s` corresponding to equivalent tensors; if there are two `h` which are the same apart from the sign, return zero; otherwise choose as representative the tensor with indices ordered lexicographically according to `[d1, -d1, d2, -d2, d3, -d3]` that is `rep = min(D*g*S) = min([d*g*s for d in D for s in S])` The indices are fixed one by one; first choose the lowest index for slot 0, then the lowest remaining index for slot 1, etc. Doing this one obtains a chain of stabilizers `S -> S_{b0} -> S_{b0,b1} -> ...` and `D -> D_{p0} -> D_{p0,p1} -> ...` where `[b0, b1, ...] = range(b)` is a base of the symmetric group; the strong base `b_S` of S is an ordered sublist of it; therefore it is sufficient to compute once the strong base generators of S using the Schreier-Sims algorithm; the stabilizers of the strong base generators are the strong base generators of the stabilizer subgroup. `dbase = [p0, p1, ...]` is not in general in lexicographic order, so that one must recompute the strong base generators each time; however this is trivial, there is no need to use the Schreier-Sims algorithm for D. The algorithm keeps a TAB of elements `(s_i, d_i, h_i)` where `h_i = d_i*g*s_i` satisfying `h_i[j] = p_j` for `0 <= j < i` starting from `s_0 = id, d_0 = id, h_0 = g`. The equations `h_0[0] = p_0, h_1[1] = p_1,...` are solved in this order, choosing each time the lowest possible value of p_i For `j < i` `d_i*g*s_i*S_{b_0,...,b_{i-1}}*b_j = D_{p_0,...,p_{i-1}}*p_j` so that for dx in `D_{p_0,...,p_{i-1}}` and sx in `S_{base[0],...,base[i-1]}` one has `dx*d_i*g*s_i*sx*b_j = p_j` Search for dx, sx such that this equation holds for `j = i`; it can be written as `s_i*sx*b_j = J, dx*d_i*g*J = p_j` `sx*b_j = s_i**-1*J; sx = trace(s_i**-1, S_{b_0,...,b_{i-1}})` `dx**-1*p_j = d_i*g*J; dx = trace(d_i*g*J, D_{p_0,...,p_{i-1}})` `s_{i+1} = s_i*trace(s_i**-1*J, S_{b_0,...,b_{i-1}})` `d_{i+1} = trace(d_i*g*J, D_{p_0,...,p_{i-1}})**-1*d_i` `h_{i+1}*b_i = d_{i+1}*g*s_{i+1}*b_i = p_i` `h_n*b_j = p_j` for all j, so that `h_n` is the solution. Add the found `(s, d, h)` to TAB1. At the end of the iteration sort TAB1 with respect to the `h`; if there are two consecutive `h` in TAB1 which differ only for the sign, the tensor is zero, so return 0; if there are two consecutive `h` which are equal, keep only one. Then stabilize the slot generators under `i` and the dummy generators under `p_i`. Assign `TAB = TAB1` at the end of the iteration step. At the end `TAB` contains a unique `(s, d, h)`, since all the slots of the tensor `h` have been fixed to have the minimum value according to the symmetries. The algorithm returns `h`. It is important that the slot BSGS has lexicographic minimal base, otherwise there is an `i` which does not belong to the slot base for which `p_i` is fixed by the dummy symmetry only, while `i` is not invariant from the slot stabilizer, so `p_i` is not in general the minimal value. This algorithm differs slightly from the original algorithm [3]: the canonical form is minimal lexicographically, and the BSGS has minimal base under lexicographic order. Equal tensors `h` are eliminated from TAB. Examples ======== >>> from sympy.combinatorics.permutations import Permutation >>> from sympy.combinatorics.tensor_can import double_coset_can_rep, get_transversals >>> gens = [Permutation(x) for x in [[2, 1, 0, 3, 4, 5, 7, 6], [4, 1, 2, 3, 0, 5, 7, 6]]] >>> base = [0, 2] >>> g = Permutation([4, 2, 0, 1, 3, 5, 6, 7]) >>> transversals = get_transversals(base, gens) >>> double_coset_can_rep([list(range(6))], [0], base, gens, transversals, g) [0, 1, 2, 3, 4, 5, 7, 6] >>> g = Permutation([4, 1, 3, 0, 5, 2, 6, 7]) >>> double_coset_can_rep([list(range(6))], [0], base, gens, transversals, g) 0 """ size = g.size g = g.array_form num_dummies = size - 2 indices = list(range(num_dummies)) all_metrics_with_sym = all([_ is not None for _ in sym]) num_types = len(sym) dumx = dummies[:] dumx_flat = [] for dx in dumx: dumx_flat.extend(dx) b_S = b_S[:] sgensx = [h._array_form for h in sgens] if b_S: S_transversals = transversal2coset(size, b_S, S_transversals) # strong generating set for D dsgsx = [] for i in range(num_types): dsgsx.extend(dummy_sgs(dumx[i], sym[i], num_dummies)) idn = list(range(size)) # TAB = list of entries (s, d, h) where h = _af_rmuln(d,g,s) # for short, in the following d*g*s means _af_rmuln(d,g,s) TAB = [(idn, idn, g)] for i in range(size - 2): b = i testb = b in b_S and sgensx if testb: sgensx1 = [_af_new(_) for _ in sgensx] deltab = _orbit(size, sgensx1, b) else: deltab = {b} # p1 = min(IMAGES) = min(Union D_p*h*deltab for h in TAB) if all_metrics_with_sym: md = _min_dummies(dumx, sym, indices) else: md = [min(_orbit(size, [_af_new( ddx) for ddx in dsgsx], ii)) for ii in range(size - 2)] p_i = min([min([md[h[x]] for x in deltab]) for s, d, h in TAB]) dsgsx1 = [_af_new(_) for _ in dsgsx] Dxtrav = _orbit_transversal(size, dsgsx1, p_i, False, af=True) \ if dsgsx else None if Dxtrav: Dxtrav = [_af_invert(x) for x in Dxtrav] # compute the orbit of p_i for ii in range(num_types): if p_i in dumx[ii]: # the orbit is made by all the indices in dum[ii] if sym[ii] is not None: deltap = dumx[ii] else: # the orbit is made by all the even indices if p_i # is even, by all the odd indices if p_i is odd p_i_index = dumx[ii].index(p_i) % 2 deltap = dumx[ii][p_i_index::2] break else: deltap = [p_i] TAB1 = [] while TAB: s, d, h = TAB.pop() if min([md[h[x]] for x in deltab]) != p_i: continue deltab1 = [x for x in deltab if md[h[x]] == p_i] # NEXT = s*deltab1 intersection (d*g)**-1*deltap dg = _af_rmul(d, g) dginv = _af_invert(dg) sdeltab = [s[x] for x in deltab1] gdeltap = [dginv[x] for x in deltap] NEXT = [x for x in sdeltab if x in gdeltap] # d, s satisfy # d*g*s*base[i-1] = p_{i-1}; using the stabilizers # d*g*s*S_{base[0],...,base[i-1]}*base[i-1] = # D_{p_0,...,p_{i-1}}*p_{i-1} # so that to find d1, s1 satisfying d1*g*s1*b = p_i # one can look for dx in D_{p_0,...,p_{i-1}} and # sx in S_{base[0],...,base[i-1]} # d1 = dx*d; s1 = s*sx # d1*g*s1*b = dx*d*g*s*sx*b = p_i for j in NEXT: if testb: # solve s1*b = j with s1 = s*sx for some element sx # of the stabilizer of ..., base[i-1] # sx*b = s**-1*j; sx = _trace_S(s, j,...) # s1 = s*trace_S(s**-1*j,...) s1 = _trace_S(s, j, b, S_transversals) if not s1: continue else: s1 = [s[ix] for ix in s1] else: s1 = s # assert s1[b] == j # invariant # solve d1*g*j = p_i with d1 = dx*d for some element dg # of the stabilizer of ..., p_{i-1} # dx**-1*p_i = d*g*j; dx**-1 = trace_D(d*g*j,...) # d1 = trace_D(d*g*j,...)**-1*d # to save an inversion in the inner loop; notice we did # Dxtrav = [perm_af_invert(x) for x in Dxtrav] out of the loop if Dxtrav: d1 = _trace_D(dg[j], p_i, Dxtrav) if not d1: continue else: if p_i != dg[j]: continue d1 = idn assert d1[dg[j]] == p_i # invariant d1 = [d1[ix] for ix in d] h1 = [d1[g[ix]] for ix in s1] # assert h1[b] == p_i # invariant TAB1.append((s1, d1, h1)) # if TAB contains equal permutations, keep only one of them; # if TAB contains equal permutations up to the sign, return 0 TAB1.sort(key=lambda x: x[-1]) prev = [0] * size while TAB1: s, d, h = TAB1.pop() if h[:-2] == prev[:-2]: if h[-1] != prev[-1]: return 0 else: TAB.append((s, d, h)) prev = h # stabilize the SGS sgensx = [h for h in sgensx if h[b] == b] if b in b_S: b_S.remove(b) _dumx_remove(dumx, dumx_flat, p_i) dsgsx = [] for i in range(num_types): dsgsx.extend(dummy_sgs(dumx[i], sym[i], num_dummies)) return TAB[0][-1] def canonical_free(base, gens, g, num_free): """ Canonicalization of a tensor with respect to free indices choosing the minimum with respect to lexicographical ordering in the free indices. Explanation =========== ``base``, ``gens`` BSGS for slot permutation group ``g`` permutation representing the tensor ``num_free`` number of free indices The indices must be ordered with first the free indices See explanation in double_coset_can_rep The algorithm is a variation of the one given in [2]. Examples ======== >>> from sympy.combinatorics import Permutation >>> from sympy.combinatorics.tensor_can import canonical_free >>> gens = [[1, 0, 2, 3, 5, 4], [2, 3, 0, 1, 4, 5],[0, 1, 3, 2, 5, 4]] >>> gens = [Permutation(h) for h in gens] >>> base = [0, 2] >>> g = Permutation([2, 1, 0, 3, 4, 5]) >>> canonical_free(base, gens, g, 4) [0, 3, 1, 2, 5, 4] Consider the product of Riemann tensors ``T = R^{a}_{d0}^{d1,d2}*R_{d2,d1}^{d0,b}`` The order of the indices is ``[a, b, d0, -d0, d1, -d1, d2, -d2]`` The permutation corresponding to the tensor is ``g = [0, 3, 4, 6, 7, 5, 2, 1, 8, 9]`` In particular ``a`` is position ``0``, ``b`` is in position ``9``. Use the slot symmetries to get `T` is a form which is the minimal in lexicographic order in the free indices ``a`` and ``b``, e.g. ``-R^{a}_{d0}^{d1,d2}*R^{b,d0}_{d2,d1}`` corresponding to ``[0, 3, 4, 6, 1, 2, 7, 5, 9, 8]`` >>> from sympy.combinatorics.tensor_can import riemann_bsgs, tensor_gens >>> base, gens = riemann_bsgs >>> size, sbase, sgens = tensor_gens(base, gens, [[], []], 0) >>> g = Permutation([0, 3, 4, 6, 7, 5, 2, 1, 8, 9]) >>> canonical_free(sbase, [Permutation(h) for h in sgens], g, 2) [0, 3, 4, 6, 1, 2, 7, 5, 9, 8] """ g = g.array_form size = len(g) if not base: return g[:] transversals = get_transversals(base, gens) for x in sorted(g[:-2]): if x not in base: base.append(x) h = g for i, transv in enumerate(transversals): h_i = [size]*num_free # find the element s in transversals[i] such that # _af_rmul(h, s) has its free elements with the lowest position in h s = None for sk in transv.values(): h1 = _af_rmul(h, sk) hi = [h1.index(ix) for ix in range(num_free)] if hi < h_i: h_i = hi s = sk if s: h = _af_rmul(h, s) return h def _get_map_slots(size, fixed_slots): res = list(range(size)) pos = 0 for i in range(size): if i in fixed_slots: continue res[i] = pos pos += 1 return res def _lift_sgens(size, fixed_slots, free, s): a = [] j = k = 0 fd = list(zip(fixed_slots, free)) fd = [y for x, y in sorted(fd)] num_free = len(free) for i in range(size): if i in fixed_slots: a.append(fd[k]) k += 1 else: a.append(s[j] + num_free) j += 1 return a def canonicalize(g, dummies, msym, *v): """ canonicalize tensor formed by tensors Parameters ========== g : permutation representing the tensor dummies : list representing the dummy indices it can be a list of dummy indices of the same type or a list of lists of dummy indices, one list for each type of index; the dummy indices must come after the free indices, and put in order contravariant, covariant [d0, -d0, d1,-d1,...] msym : symmetry of the metric(s) it can be an integer or a list; in the first case it is the symmetry of the dummy index metric; in the second case it is the list of the symmetries of the index metric for each type v : list, (base_i, gens_i, n_i, sym_i) for tensors of type `i` base_i, gens_i : BSGS for tensors of this type. The BSGS should have minimal base under lexicographic ordering; if not, an attempt is made do get the minimal BSGS; in case of failure, canonicalize_naive is used, which is much slower. n_i : number of tensors of type `i`. sym_i : symmetry under exchange of component tensors of type `i`. Both for msym and sym_i the cases are * None no symmetry * 0 commuting * 1 anticommuting Returns ======= 0 if the tensor is zero, else return the array form of the permutation representing the canonical form of the tensor. Algorithm ========= First one uses canonical_free to get the minimum tensor under lexicographic order, using only the slot symmetries. If the component tensors have not minimal BSGS, it is attempted to find it; if the attempt fails canonicalize_naive is used instead. Compute the residual slot symmetry keeping fixed the free indices using tensor_gens(base, gens, list_free_indices, sym). Reduce the problem eliminating the free indices. Then use double_coset_can_rep and lift back the result reintroducing the free indices. Examples ======== one type of index with commuting metric; `A_{a b}` and `B_{a b}` antisymmetric and commuting `T = A_{d0 d1} * B^{d0}{}_{d2} * B^{d2 d1}` `ord = [d0,-d0,d1,-d1,d2,-d2]` order of the indices g = [1, 3, 0, 5, 4, 2, 6, 7] `T_c = 0` >>> from sympy.combinatorics.tensor_can import get_symmetric_group_sgs, canonicalize, bsgs_direct_product >>> from sympy.combinatorics import Permutation >>> base2a, gens2a = get_symmetric_group_sgs(2, 1) >>> t0 = (base2a, gens2a, 1, 0) >>> t1 = (base2a, gens2a, 2, 0) >>> g = Permutation([1, 3, 0, 5, 4, 2, 6, 7]) >>> canonicalize(g, range(6), 0, t0, t1) 0 same as above, but with `B_{a b}` anticommuting `T_c = -A^{d0 d1} * B_{d0}{}^{d2} * B_{d1 d2}` can = [0,2,1,4,3,5,7,6] >>> t1 = (base2a, gens2a, 2, 1) >>> canonicalize(g, range(6), 0, t0, t1) [0, 2, 1, 4, 3, 5, 7, 6] two types of indices `[a,b,c,d,e,f]` and `[m,n]`, in this order, both with commuting metric `f^{a b c}` antisymmetric, commuting `A_{m a}` no symmetry, commuting `T = f^c{}_{d a} * f^f{}_{e b} * A_m{}^d * A^{m b} * A_n{}^a * A^{n e}` ord = [c,f,a,-a,b,-b,d,-d,e,-e,m,-m,n,-n] g = [0,7,3, 1,9,5, 11,6, 10,4, 13,2, 12,8, 14,15] The canonical tensor is `T_c = -f^{c a b} * f^{f d e} * A^m{}_a * A_{m d} * A^n{}_b * A_{n e}` can = [0,2,4, 1,6,8, 10,3, 11,7, 12,5, 13,9, 15,14] >>> base_f, gens_f = get_symmetric_group_sgs(3, 1) >>> base1, gens1 = get_symmetric_group_sgs(1) >>> base_A, gens_A = bsgs_direct_product(base1, gens1, base1, gens1) >>> t0 = (base_f, gens_f, 2, 0) >>> t1 = (base_A, gens_A, 4, 0) >>> dummies = [range(2, 10), range(10, 14)] >>> g = Permutation([0, 7, 3, 1, 9, 5, 11, 6, 10, 4, 13, 2, 12, 8, 14, 15]) >>> canonicalize(g, dummies, [0, 0], t0, t1) [0, 2, 4, 1, 6, 8, 10, 3, 11, 7, 12, 5, 13, 9, 15, 14] """ from sympy.combinatorics.testutil import canonicalize_naive if not isinstance(msym, list): if not msym in [0, 1, None]: raise ValueError('msym must be 0, 1 or None') num_types = 1 else: num_types = len(msym) if not all(msymx in [0, 1, None] for msymx in msym): raise ValueError('msym entries must be 0, 1 or None') if len(dummies) != num_types: raise ValueError( 'dummies and msym must have the same number of elements') size = g.size num_tensors = 0 v1 = [] for i in range(len(v)): base_i, gens_i, n_i, sym_i = v[i] # check that the BSGS is minimal; # this property is used in double_coset_can_rep; # if it is not minimal use canonicalize_naive if not _is_minimal_bsgs(base_i, gens_i): mbsgs = get_minimal_bsgs(base_i, gens_i) if not mbsgs: can = canonicalize_naive(g, dummies, msym, *v) return can base_i, gens_i = mbsgs v1.append((base_i, gens_i, [[]] * n_i, sym_i)) num_tensors += n_i if num_types == 1 and not isinstance(msym, list): dummies = [dummies] msym = [msym] flat_dummies = [] for dumx in dummies: flat_dummies.extend(dumx) if flat_dummies and flat_dummies != list(range(flat_dummies[0], flat_dummies[-1] + 1)): raise ValueError('dummies is not valid') # slot symmetry of the tensor size1, sbase, sgens = gens_products(*v1) if size != size1: raise ValueError( 'g has size %d, generators have size %d' % (size, size1)) free = [i for i in range(size - 2) if i not in flat_dummies] num_free = len(free) # g1 minimal tensor under slot symmetry g1 = canonical_free(sbase, sgens, g, num_free) if not flat_dummies: return g1 # save the sign of g1 sign = 0 if g1[-1] == size - 1 else 1 # the free indices are kept fixed. # Determine free_i, the list of slots of tensors which are fixed # since they are occupied by free indices, which are fixed. start = 0 for i in range(len(v)): free_i = [] base_i, gens_i, n_i, sym_i = v[i] len_tens = gens_i[0].size - 2 # for each component tensor get a list od fixed islots for j in range(n_i): # get the elements corresponding to the component tensor h = g1[start:(start + len_tens)] fr = [] # get the positions of the fixed elements in h for k in free: if k in h: fr.append(h.index(k)) free_i.append(fr) start += len_tens v1[i] = (base_i, gens_i, free_i, sym_i) # BSGS of the tensor with fixed free indices # if tensor_gens fails in gens_product, use canonicalize_naive size, sbase, sgens = gens_products(*v1) # reduce the permutations getting rid of the free indices pos_free = [g1.index(x) for x in range(num_free)] size_red = size - num_free g1_red = [x - num_free for x in g1 if x in flat_dummies] if sign: g1_red.extend([size_red - 1, size_red - 2]) else: g1_red.extend([size_red - 2, size_red - 1]) map_slots = _get_map_slots(size, pos_free) sbase_red = [map_slots[i] for i in sbase if i not in pos_free] sgens_red = [_af_new([map_slots[i] for i in y._array_form if i not in pos_free]) for y in sgens] dummies_red = [[x - num_free for x in y] for y in dummies] transv_red = get_transversals(sbase_red, sgens_red) g1_red = _af_new(g1_red) g2 = double_coset_can_rep( dummies_red, msym, sbase_red, sgens_red, transv_red, g1_red) if g2 == 0: return 0 # lift to the case with the free indices g3 = _lift_sgens(size, pos_free, free, g2) return g3 def perm_af_direct_product(gens1, gens2, signed=True): """ Direct products of the generators gens1 and gens2. Examples ======== >>> from sympy.combinatorics.tensor_can import perm_af_direct_product >>> gens1 = [[1, 0, 2, 3], [0, 1, 3, 2]] >>> gens2 = [[1, 0]] >>> perm_af_direct_product(gens1, gens2, False) [[1, 0, 2, 3, 4, 5], [0, 1, 3, 2, 4, 5], [0, 1, 2, 3, 5, 4]] >>> gens1 = [[1, 0, 2, 3, 5, 4], [0, 1, 3, 2, 4, 5]] >>> gens2 = [[1, 0, 2, 3]] >>> perm_af_direct_product(gens1, gens2, True) [[1, 0, 2, 3, 4, 5, 7, 6], [0, 1, 3, 2, 4, 5, 6, 7], [0, 1, 2, 3, 5, 4, 6, 7]] """ gens1 = [list(x) for x in gens1] gens2 = [list(x) for x in gens2] s = 2 if signed else 0 n1 = len(gens1[0]) - s n2 = len(gens2[0]) - s start = list(range(n1)) end = list(range(n1, n1 + n2)) if signed: gens1 = [gen[:-2] + end + [gen[-2] + n2, gen[-1] + n2] for gen in gens1] gens2 = [start + [x + n1 for x in gen] for gen in gens2] else: gens1 = [gen + end for gen in gens1] gens2 = [start + [x + n1 for x in gen] for gen in gens2] res = gens1 + gens2 return res def bsgs_direct_product(base1, gens1, base2, gens2, signed=True): """ Direct product of two BSGS. Parameters ========== base1 : base of the first BSGS. gens1 : strong generating sequence of the first BSGS. base2, gens2 : similarly for the second BSGS. signed : flag for signed permutations. Examples ======== >>> from sympy.combinatorics.tensor_can import (get_symmetric_group_sgs, bsgs_direct_product) >>> base1, gens1 = get_symmetric_group_sgs(1) >>> base2, gens2 = get_symmetric_group_sgs(2) >>> bsgs_direct_product(base1, gens1, base2, gens2) ([1], [(4)(1 2)]) """ s = 2 if signed else 0 n1 = gens1[0].size - s base = list(base1) base += [x + n1 for x in base2] gens1 = [h._array_form for h in gens1] gens2 = [h._array_form for h in gens2] gens = perm_af_direct_product(gens1, gens2, signed) size = len(gens[0]) id_af = list(range(size)) gens = [h for h in gens if h != id_af] if not gens: gens = [id_af] return base, [_af_new(h) for h in gens] def get_symmetric_group_sgs(n, antisym=False): """ Return base, gens of the minimal BSGS for (anti)symmetric tensor Parameters ========== ``n``: rank of the tensor ``antisym`` : bool ``antisym = False`` symmetric tensor ``antisym = True`` antisymmetric tensor Examples ======== >>> from sympy.combinatorics.tensor_can import get_symmetric_group_sgs >>> get_symmetric_group_sgs(3) ([0, 1], [(4)(0 1), (4)(1 2)]) """ if n == 1: return [], [_af_new(list(range(3)))] gens = [Permutation(n - 1)(i, i + 1)._array_form for i in range(n - 1)] if antisym == 0: gens = [x + [n, n + 1] for x in gens] else: gens = [x + [n + 1, n] for x in gens] base = list(range(n - 1)) return base, [_af_new(h) for h in gens] riemann_bsgs = [0, 2], [Permutation(0, 1)(4, 5), Permutation(2, 3)(4, 5), Permutation(5)(0, 2)(1, 3)] def get_transversals(base, gens): """ Return transversals for the group with BSGS base, gens """ if not base: return [] stabs = _distribute_gens_by_base(base, gens) orbits, transversals = _orbits_transversals_from_bsgs(base, stabs) transversals = [{x: h._array_form for x, h in y.items()} for y in transversals] return transversals def _is_minimal_bsgs(base, gens): """ Check if the BSGS has minimal base under lexigographic order. base, gens BSGS Examples ======== >>> from sympy.combinatorics import Permutation >>> from sympy.combinatorics.tensor_can import riemann_bsgs, _is_minimal_bsgs >>> _is_minimal_bsgs(*riemann_bsgs) True >>> riemann_bsgs1 = ([2, 0], ([Permutation(5)(0, 1)(4, 5), Permutation(5)(0, 2)(1, 3)])) >>> _is_minimal_bsgs(*riemann_bsgs1) False """ base1 = [] sgs1 = gens[:] size = gens[0].size for i in range(size): if not all(h._array_form[i] == i for h in sgs1): base1.append(i) sgs1 = [h for h in sgs1 if h._array_form[i] == i] return base1 == base def get_minimal_bsgs(base, gens): """ Compute a minimal GSGS base, gens BSGS If base, gens is a minimal BSGS return it; else return a minimal BSGS if it fails in finding one, it returns None TODO: use baseswap in the case in which if it fails in finding a minimal BSGS Examples ======== >>> from sympy.combinatorics import Permutation >>> from sympy.combinatorics.tensor_can import get_minimal_bsgs >>> riemann_bsgs1 = ([2, 0], ([Permutation(5)(0, 1)(4, 5), Permutation(5)(0, 2)(1, 3)])) >>> get_minimal_bsgs(*riemann_bsgs1) ([0, 2], [(0 1)(4 5), (5)(0 2)(1 3), (2 3)(4 5)]) """ G = PermutationGroup(gens) base, gens = G.schreier_sims_incremental() if not _is_minimal_bsgs(base, gens): return None return base, gens def tensor_gens(base, gens, list_free_indices, sym=0): """ Returns size, res_base, res_gens BSGS for n tensors of the same type. Explanation =========== base, gens BSGS for tensors of this type list_free_indices list of the slots occupied by fixed indices for each of the tensors sym symmetry under commutation of two tensors sym None no symmetry sym 0 commuting sym 1 anticommuting Examples ======== >>> from sympy.combinatorics.tensor_can import tensor_gens, get_symmetric_group_sgs two symmetric tensors with 3 indices without free indices >>> base, gens = get_symmetric_group_sgs(3) >>> tensor_gens(base, gens, [[], []]) (8, [0, 1, 3, 4], [(7)(0 1), (7)(1 2), (7)(3 4), (7)(4 5), (7)(0 3)(1 4)(2 5)]) two symmetric tensors with 3 indices with free indices in slot 1 and 0 >>> tensor_gens(base, gens, [[1], [0]]) (8, [0, 4], [(7)(0 2), (7)(4 5)]) four symmetric tensors with 3 indices, two of which with free indices """ def _get_bsgs(G, base, gens, free_indices): """ return the BSGS for G.pointwise_stabilizer(free_indices) """ if not free_indices: return base[:], gens[:] else: H = G.pointwise_stabilizer(free_indices) base, sgs = H.schreier_sims_incremental() return base, sgs # if not base there is no slot symmetry for the component tensors # if list_free_indices.count([]) < 2 there is no commutation symmetry # so there is no resulting slot symmetry if not base and list_free_indices.count([]) < 2: n = len(list_free_indices) size = gens[0].size size = n * (size - 2) + 2 return size, [], [_af_new(list(range(size)))] # if any(list_free_indices) one needs to compute the pointwise # stabilizer, so G is needed if any(list_free_indices): G = PermutationGroup(gens) else: G = None # no_free list of lists of indices for component tensors without fixed # indices no_free = [] size = gens[0].size id_af = list(range(size)) num_indices = size - 2 if not list_free_indices[0]: no_free.append(list(range(num_indices))) res_base, res_gens = _get_bsgs(G, base, gens, list_free_indices[0]) for i in range(1, len(list_free_indices)): base1, gens1 = _get_bsgs(G, base, gens, list_free_indices[i]) res_base, res_gens = bsgs_direct_product(res_base, res_gens, base1, gens1, 1) if not list_free_indices[i]: no_free.append(list(range(size - 2, size - 2 + num_indices))) size += num_indices nr = size - 2 res_gens = [h for h in res_gens if h._array_form != id_af] # if sym there are no commuting tensors stop here if sym is None or not no_free: if not res_gens: res_gens = [_af_new(id_af)] return size, res_base, res_gens # if the component tensors have moinimal BSGS, so is their direct # product P; the slot symmetry group is S = P*C, where C is the group # to (anti)commute the component tensors with no free indices # a stabilizer has the property S_i = P_i*C_i; # the BSGS of P*C has SGS_P + SGS_C and the base is # the ordered union of the bases of P and C. # If P has minimal BSGS, so has S with this base. base_comm = [] for i in range(len(no_free) - 1): ind1 = no_free[i] ind2 = no_free[i + 1] a = list(range(ind1[0])) a.extend(ind2) a.extend(ind1) base_comm.append(ind1[0]) a.extend(list(range(ind2[-1] + 1, nr))) if sym == 0: a.extend([nr, nr + 1]) else: a.extend([nr + 1, nr]) res_gens.append(_af_new(a)) res_base = list(res_base) # each base is ordered; order the union of the two bases for i in base_comm: if i not in res_base: res_base.append(i) res_base.sort() if not res_gens: res_gens = [_af_new(id_af)] return size, res_base, res_gens def gens_products(*v): """ Returns size, res_base, res_gens BSGS for n tensors of different types. Explanation =========== v is a sequence of (base_i, gens_i, free_i, sym_i) where base_i, gens_i BSGS of tensor of type `i` free_i list of the fixed slots for each of the tensors of type `i`; if there are `n_i` tensors of type `i` and none of them have fixed slots, `free = [[]]*n_i` sym 0 (1) if the tensors of type `i` (anti)commute among themselves Examples ======== >>> from sympy.combinatorics.tensor_can import get_symmetric_group_sgs, gens_products >>> base, gens = get_symmetric_group_sgs(2) >>> gens_products((base, gens, [[], []], 0)) (6, [0, 2], [(5)(0 1), (5)(2 3), (5)(0 2)(1 3)]) >>> gens_products((base, gens, [[1], []], 0)) (6, [2], [(5)(2 3)]) """ res_size, res_base, res_gens = tensor_gens(*v[0]) for i in range(1, len(v)): size, base, gens = tensor_gens(*v[i]) res_base, res_gens = bsgs_direct_product(res_base, res_gens, base, gens, 1) res_size = res_gens[0].size id_af = list(range(res_size)) res_gens = [h for h in res_gens if h != id_af] if not res_gens: res_gens = [id_af] return res_size, res_base, res_gens
e42e170d72b3ca4191b63c34dda69cd33d915482c822bb830de24744c225e61c
""" Limits ====== Implemented according to the PhD thesis http://www.cybertester.com/data/gruntz.pdf, which contains very thorough descriptions of the algorithm including many examples. We summarize here the gist of it. All functions are sorted according to how rapidly varying they are at infinity using the following rules. Any two functions f and g can be compared using the properties of L: L=lim log|f(x)| / log|g(x)| (for x -> oo) We define >, < ~ according to:: 1. f > g .... L=+-oo we say that: - f is greater than any power of g - f is more rapidly varying than g - f goes to infinity/zero faster than g 2. f < g .... L=0 we say that: - f is lower than any power of g 3. f ~ g .... L!=0, +-oo we say that: - both f and g are bounded from above and below by suitable integral powers of the other Examples ======== :: 2 < x < exp(x) < exp(x**2) < exp(exp(x)) 2 ~ 3 ~ -5 x ~ x**2 ~ x**3 ~ 1/x ~ x**m ~ -x exp(x) ~ exp(-x) ~ exp(2x) ~ exp(x)**2 ~ exp(x+exp(-x)) f ~ 1/f So we can divide all the functions into comparability classes (x and x^2 belong to one class, exp(x) and exp(-x) belong to some other class). In principle, we could compare any two functions, but in our algorithm, we don't compare anything below the class 2~3~-5 (for example log(x) is below this), so we set 2~3~-5 as the lowest comparability class. Given the function f, we find the list of most rapidly varying (mrv set) subexpressions of it. This list belongs to the same comparability class. Let's say it is {exp(x), exp(2x)}. Using the rule f ~ 1/f we find an element "w" (either from the list or a new one) from the same comparability class which goes to zero at infinity. In our example we set w=exp(-x) (but we could also set w=exp(-2x) or w=exp(-3x) ...). We rewrite the mrv set using w, in our case {1/w, 1/w^2}, and substitute it into f. Then we expand f into a series in w:: f = c0*w^e0 + c1*w^e1 + ... + O(w^en), where e0<e1<...<en, c0!=0 but for x->oo, lim f = lim c0*w^e0, because all the other terms go to zero, because w goes to zero faster than the ci and ei. So:: for e0>0, lim f = 0 for e0<0, lim f = +-oo (the sign depends on the sign of c0) for e0=0, lim f = lim c0 We need to recursively compute limits at several places of the algorithm, but as is shown in the PhD thesis, it always finishes. Important functions from the implementation: compare(a, b, x) compares "a" and "b" by computing the limit L. mrv(e, x) returns list of most rapidly varying (mrv) subexpressions of "e" rewrite(e, Omega, x, wsym) rewrites "e" in terms of w leadterm(f, x) returns the lowest power term in the series of f mrv_leadterm(e, x) returns the lead term (c0, e0) for e limitinf(e, x) computes lim e (for x->oo) limit(e, z, z0) computes any limit by converting it to the case x->oo All the functions are really simple and straightforward except rewrite(), which is the most difficult/complex part of the algorithm. When the algorithm fails, the bugs are usually in the series expansion (i.e. in SymPy) or in rewrite. This code is almost exact rewrite of the Maple code inside the Gruntz thesis. Debugging --------- Because the gruntz algorithm is highly recursive, it's difficult to figure out what went wrong inside a debugger. Instead, turn on nice debug prints by defining the environment variable SYMPY_DEBUG. For example: [user@localhost]: SYMPY_DEBUG=True ./bin/isympy In [1]: limit(sin(x)/x, x, 0) limitinf(_x*sin(1/_x), _x) = 1 +-mrv_leadterm(_x*sin(1/_x), _x) = (1, 0) | +-mrv(_x*sin(1/_x), _x) = set([_x]) | | +-mrv(_x, _x) = set([_x]) | | +-mrv(sin(1/_x), _x) = set([_x]) | | +-mrv(1/_x, _x) = set([_x]) | | +-mrv(_x, _x) = set([_x]) | +-mrv_leadterm(exp(_x)*sin(exp(-_x)), _x, set([exp(_x)])) = (1, 0) | +-rewrite(exp(_x)*sin(exp(-_x)), set([exp(_x)]), _x, _w) = (1/_w*sin(_w), -_x) | +-sign(_x, _x) = 1 | +-mrv_leadterm(1, _x) = (1, 0) +-sign(0, _x) = 0 +-limitinf(1, _x) = 1 And check manually which line is wrong. Then go to the source code and debug this function to figure out the exact problem. """ from functools import reduce from sympy import cacheit from sympy.core import Basic, S, oo, I, Dummy, Wild, Mul, PoleError from sympy.functions import log, exp from sympy.series.order import Order from sympy.simplify import logcombine from sympy.simplify.powsimp import powsimp, powdenest from sympy.utilities.misc import debug_decorator as debug from sympy.utilities.timeutils import timethis timeit = timethis('gruntz') def compare(a, b, x): """Returns "<" if a<b, "=" for a == b, ">" for a>b""" # log(exp(...)) must always be simplified here for termination la, lb = log(a), log(b) if isinstance(a, Basic) and (isinstance(a, exp) or (a.is_Pow and a.base == S.Exp1)): la = a.exp if isinstance(b, Basic) and (isinstance(b, exp) or (b.is_Pow and b.base == S.Exp1)): lb = b.exp c = limitinf(la/lb, x) if c == 0: return "<" elif c.is_infinite: return ">" else: return "=" class SubsSet(dict): """ Stores (expr, dummy) pairs, and how to rewrite expr-s. Explanation =========== The gruntz algorithm needs to rewrite certain expressions in term of a new variable w. We cannot use subs, because it is just too smart for us. For example:: > Omega=[exp(exp(_p - exp(-_p))/(1 - 1/_p)), exp(exp(_p))] > O2=[exp(-exp(_p) + exp(-exp(-_p))*exp(_p)/(1 - 1/_p))/_w, 1/_w] > e = exp(exp(_p - exp(-_p))/(1 - 1/_p)) - exp(exp(_p)) > e.subs(Omega[0],O2[0]).subs(Omega[1],O2[1]) -1/w + exp(exp(p)*exp(-exp(-p))/(1 - 1/p)) is really not what we want! So we do it the hard way and keep track of all the things we potentially want to substitute by dummy variables. Consider the expression:: exp(x - exp(-x)) + exp(x) + x. The mrv set is {exp(x), exp(-x), exp(x - exp(-x))}. We introduce corresponding dummy variables d1, d2, d3 and rewrite:: d3 + d1 + x. This class first of all keeps track of the mapping expr->variable, i.e. will at this stage be a dictionary:: {exp(x): d1, exp(-x): d2, exp(x - exp(-x)): d3}. [It turns out to be more convenient this way round.] But sometimes expressions in the mrv set have other expressions from the mrv set as subexpressions, and we need to keep track of that as well. In this case, d3 is really exp(x - d2), so rewrites at this stage is:: {d3: exp(x-d2)}. The function rewrite uses all this information to correctly rewrite our expression in terms of w. In this case w can be chosen to be exp(-x), i.e. d2. The correct rewriting then is:: exp(-w)/w + 1/w + x. """ def __init__(self): self.rewrites = {} def __repr__(self): return super().__repr__() + ', ' + self.rewrites.__repr__() def __getitem__(self, key): if not key in self: self[key] = Dummy() return dict.__getitem__(self, key) def do_subs(self, e): """Substitute the variables with expressions""" for expr, var in self.items(): e = e.xreplace({var: expr}) return e def meets(self, s2): """Tell whether or not self and s2 have non-empty intersection""" return set(self.keys()).intersection(list(s2.keys())) != set() def union(self, s2, exps=None): """Compute the union of self and s2, adjusting exps""" res = self.copy() tr = {} for expr, var in s2.items(): if expr in self: if exps: exps = exps.xreplace({var: res[expr]}) tr[var] = res[expr] else: res[expr] = var for var, rewr in s2.rewrites.items(): res.rewrites[var] = rewr.xreplace(tr) return res, exps def copy(self): """Create a shallow copy of SubsSet""" r = SubsSet() r.rewrites = self.rewrites.copy() for expr, var in self.items(): r[expr] = var return r @debug def mrv(e, x): """Returns a SubsSet of most rapidly varying (mrv) subexpressions of 'e', and e rewritten in terms of these""" e = powsimp(e, deep=True, combine='exp') if not isinstance(e, Basic): raise TypeError("e should be an instance of Basic") if not e.has(x): return SubsSet(), e elif e == x: s = SubsSet() return s, s[x] elif e.is_Mul or e.is_Add: i, d = e.as_independent(x) # throw away x-independent terms if d.func != e.func: s, expr = mrv(d, x) return s, e.func(i, expr) a, b = d.as_two_terms() s1, e1 = mrv(a, x) s2, e2 = mrv(b, x) return mrv_max1(s1, s2, e.func(i, e1, e2), x) elif e.is_Pow and e.base != S.Exp1: e1 = S.One while e.is_Pow: b1 = e.base e1 *= e.exp e = b1 if b1 == 1: return SubsSet(), b1 if e1.has(x): base_lim = limitinf(b1, x) if base_lim is S.One: return mrv(exp(e1 * (b1 - 1)), x) return mrv(exp(e1 * log(b1)), x) else: s, expr = mrv(b1, x) return s, expr**e1 elif isinstance(e, log): s, expr = mrv(e.args[0], x) return s, log(expr) elif isinstance(e, exp) or (e.is_Pow and e.base == S.Exp1): # We know from the theory of this algorithm that exp(log(...)) may always # be simplified here, and doing so is vital for termination. if isinstance(e.exp, log): return mrv(e.exp.args[0], x) # if a product has an infinite factor the result will be # infinite if there is no zero, otherwise NaN; here, we # consider the result infinite if any factor is infinite li = limitinf(e.exp, x) if any(_.is_infinite for _ in Mul.make_args(li)): s1 = SubsSet() e1 = s1[e] s2, e2 = mrv(e.exp, x) su = s1.union(s2)[0] su.rewrites[e1] = exp(e2) return mrv_max3(s1, e1, s2, exp(e2), su, e1, x) else: s, expr = mrv(e.exp, x) return s, exp(expr) elif e.is_Function: l = [mrv(a, x) for a in e.args] l2 = [s for (s, _) in l if s != SubsSet()] if len(l2) != 1: # e.g. something like BesselJ(x, x) raise NotImplementedError("MRV set computation for functions in" " several variables not implemented.") s, ss = l2[0], SubsSet() args = [ss.do_subs(x[1]) for x in l] return s, e.func(*args) elif e.is_Derivative: raise NotImplementedError("MRV set computation for derviatives" " not implemented yet.") raise NotImplementedError( "Don't know how to calculate the mrv of '%s'" % e) def mrv_max3(f, expsf, g, expsg, union, expsboth, x): """ Computes the maximum of two sets of expressions f and g, which are in the same comparability class, i.e. max() compares (two elements of) f and g and returns either (f, expsf) [if f is larger], (g, expsg) [if g is larger] or (union, expsboth) [if f, g are of the same class]. """ if not isinstance(f, SubsSet): raise TypeError("f should be an instance of SubsSet") if not isinstance(g, SubsSet): raise TypeError("g should be an instance of SubsSet") if f == SubsSet(): return g, expsg elif g == SubsSet(): return f, expsf elif f.meets(g): return union, expsboth c = compare(list(f.keys())[0], list(g.keys())[0], x) if c == ">": return f, expsf elif c == "<": return g, expsg else: if c != "=": raise ValueError("c should be =") return union, expsboth def mrv_max1(f, g, exps, x): """Computes the maximum of two sets of expressions f and g, which are in the same comparability class, i.e. mrv_max1() compares (two elements of) f and g and returns the set, which is in the higher comparability class of the union of both, if they have the same order of variation. Also returns exps, with the appropriate substitutions made. """ u, b = f.union(g, exps) return mrv_max3(f, g.do_subs(exps), g, f.do_subs(exps), u, b, x) @debug @cacheit @timeit def sign(e, x): """ Returns a sign of an expression e(x) for x->oo. :: e > 0 for x sufficiently large ... 1 e == 0 for x sufficiently large ... 0 e < 0 for x sufficiently large ... -1 The result of this function is currently undefined if e changes sign arbitrarily often for arbitrarily large x (e.g. sin(x)). Note that this returns zero only if e is *constantly* zero for x sufficiently large. [If e is constant, of course, this is just the same thing as the sign of e.] """ from sympy import sign as _sign if not isinstance(e, Basic): raise TypeError("e should be an instance of Basic") if e.is_positive: return 1 elif e.is_negative: return -1 elif e.is_zero: return 0 elif not e.has(x): e = logcombine(e) return _sign(e) elif e == x: return 1 elif e.is_Mul: a, b = e.as_two_terms() sa = sign(a, x) if not sa: return 0 return sa * sign(b, x) elif isinstance(e, exp): return 1 elif e.is_Pow: if e.base == S.Exp1: return 1 s = sign(e.base, x) if s == 1: return 1 if e.exp.is_Integer: return s**e.exp elif isinstance(e, log): return sign(e.args[0] - 1, x) # if all else fails, do it the hard way c0, e0 = mrv_leadterm(e, x) return sign(c0, x) @debug @timeit @cacheit def limitinf(e, x, leadsimp=False): """Limit e(x) for x-> oo. Explanation =========== If ``leadsimp`` is True, an attempt is made to simplify the leading term of the series expansion of ``e``. That may succeed even if ``e`` cannot be simplified. """ # rewrite e in terms of tractable functions only if not e.has(x): return e # e is a constant if e.has(Order): e = e.expand().removeO() if not x.is_positive or x.is_integer: # We make sure that x.is_positive is True and x.is_integer is None # so we get all the correct mathematical behavior from the expression. # We need a fresh variable. p = Dummy('p', positive=True) e = e.subs(x, p) x = p e = e.rewrite('tractable', deep=True, limitvar=x) e = powdenest(e) c0, e0 = mrv_leadterm(e, x) sig = sign(e0, x) if sig == 1: return S.Zero # e0>0: lim f = 0 elif sig == -1: # e0<0: lim f = +-oo (the sign depends on the sign of c0) if c0.match(I*Wild("a", exclude=[I])): return c0*oo s = sign(c0, x) # the leading term shouldn't be 0: if s == 0: raise ValueError("Leading term should not be 0") return s*oo elif sig == 0: if leadsimp: c0 = c0.simplify() return limitinf(c0, x, leadsimp) # e0=0: lim f = lim c0 else: raise ValueError("{} could not be evaluated".format(sig)) def moveup2(s, x): r = SubsSet() for expr, var in s.items(): r[expr.xreplace({x: exp(x)})] = var for var, expr in s.rewrites.items(): r.rewrites[var] = s.rewrites[var].xreplace({x: exp(x)}) return r def moveup(l, x): return [e.xreplace({x: exp(x)}) for e in l] @debug @timeit def calculate_series(e, x, logx=None): """ Calculates at least one term of the series of ``e`` in ``x``. This is a place that fails most often, so it is in its own function. """ from sympy.polys import cancel from sympy.simplify import bottom_up for t in e.lseries(x, logx=logx): # bottom_up function is required for a specific case - when e is # -exp(p/(p + 1)) + exp(-p**2/(p + 1) + p). No current simplification # methods reduce this to 0 while not expanding polynomials. t = bottom_up(t, lambda w: getattr(w, 'normal', lambda: w)()) t = cancel(t, expand=False).factor() if t.has(exp) and t.has(log): t = powdenest(t) if not t.is_zero: break return t @debug @timeit @cacheit def mrv_leadterm(e, x): """Returns (c0, e0) for e.""" Omega = SubsSet() if not e.has(x): return (e, S.Zero) if Omega == SubsSet(): Omega, exps = mrv(e, x) if not Omega: # e really does not depend on x after simplification return exps, S.Zero if x in Omega: # move the whole omega up (exponentiate each term): Omega_up = moveup2(Omega, x) exps_up = moveup([exps], x)[0] # NOTE: there is no need to move this down! Omega = Omega_up exps = exps_up # # The positive dummy, w, is used here so log(w*2) etc. will expand; # a unique dummy is needed in this algorithm # # For limits of complex functions, the algorithm would have to be # improved, or just find limits of Re and Im components separately. # w = Dummy("w", real=True, positive=True) f, logw = rewrite(exps, Omega, x, w) series = calculate_series(f, w, logx=logw) try: lt = series.leadterm(w, logx=logw) except (ValueError, PoleError): lt = f.as_coeff_exponent(w) # as_coeff_exponent won't always split in required form. It may simply # return (f, 0) when a better form may be obtained. Example (-x)**(-pi) # can be written as (-1**(-pi), -pi) which as_coeff_exponent does not return if lt[0].has(w): base = f.as_base_exp()[0].as_coeff_exponent(w) ex = f.as_base_exp()[1] lt = (base[0]**ex, base[1]*ex) return (lt[0].subs(log(w), logw), lt[1]) def build_expression_tree(Omega, rewrites): r""" Helper function for rewrite. We need to sort Omega (mrv set) so that we replace an expression before we replace any expression in terms of which it has to be rewritten:: e1 ---> e2 ---> e3 \ -> e4 Here we can do e1, e2, e3, e4 or e1, e2, e4, e3. To do this we assemble the nodes into a tree, and sort them by height. This function builds the tree, rewrites then sorts the nodes. """ class Node: def ht(self): return reduce(lambda x, y: x + y, [x.ht() for x in self.before], 1) nodes = {} for expr, v in Omega: n = Node() n.before = [] n.var = v n.expr = expr nodes[v] = n for _, v in Omega: if v in rewrites: n = nodes[v] r = rewrites[v] for _, v2 in Omega: if r.has(v2): n.before.append(nodes[v2]) return nodes @debug @timeit def rewrite(e, Omega, x, wsym): """e(x) ... the function Omega ... the mrv set wsym ... the symbol which is going to be used for w Returns the rewritten e in terms of w and log(w). See test_rewrite1() for examples and correct results. """ from sympy import ilcm if not isinstance(Omega, SubsSet): raise TypeError("Omega should be an instance of SubsSet") if len(Omega) == 0: raise ValueError("Length can not be 0") # all items in Omega must be exponentials for t in Omega.keys(): if not isinstance(t, exp): raise ValueError("Value should be exp") rewrites = Omega.rewrites Omega = list(Omega.items()) nodes = build_expression_tree(Omega, rewrites) Omega.sort(key=lambda x: nodes[x[1]].ht(), reverse=True) # make sure we know the sign of each exp() term; after the loop, # g is going to be the "w" - the simplest one in the mrv set for g, _ in Omega: sig = sign(g.exp, x) if sig != 1 and sig != -1: raise NotImplementedError('Result depends on the sign of %s' % sig) if sig == 1: wsym = 1/wsym # if g goes to oo, substitute 1/w # O2 is a list, which results by rewriting each item in Omega using "w" O2 = [] denominators = [] for f, var in Omega: c = limitinf(f.exp/g.exp, x) if c.is_Rational: denominators.append(c.q) arg = f.exp if var in rewrites: if not isinstance(rewrites[var], exp): raise ValueError("Value should be exp") arg = rewrites[var].args[0] O2.append((var, exp((arg - c*g.exp).expand())*wsym**c)) # Remember that Omega contains subexpressions of "e". So now we find # them in "e" and substitute them for our rewriting, stored in O2 # the following powsimp is necessary to automatically combine exponentials, # so that the .xreplace() below succeeds: # TODO this should not be necessary f = powsimp(e, deep=True, combine='exp') for a, b in O2: f = f.xreplace({a: b}) for _, var in Omega: assert not f.has(var) # finally compute the logarithm of w (logw). logw = g.exp if sig == 1: logw = -logw # log(w)->log(1/w)=-log(w) # Some parts of sympy have difficulty computing series expansions with # non-integral exponents. The following heuristic improves the situation: exponent = reduce(ilcm, denominators, 1) f = f.subs({wsym: wsym**exponent}) logw /= exponent return f, logw def gruntz(e, z, z0, dir="+"): """ Compute the limit of e(z) at the point z0 using the Gruntz algorithm. Explanation =========== ``z0`` can be any expression, including oo and -oo. For ``dir="+"`` (default) it calculates the limit from the right (z->z0+) and for ``dir="-"`` the limit from the left (z->z0-). For infinite z0 (oo or -oo), the dir argument doesn't matter. This algorithm is fully described in the module docstring in the gruntz.py file. It relies heavily on the series expansion. Most frequently, gruntz() is only used if the faster limit() function (which uses heuristics) fails. """ if not z.is_symbol: raise NotImplementedError("Second argument must be a Symbol") # convert all limits to the limit z->oo; sign of z is handled in limitinf r = None if z0 == oo: e0 = e elif z0 == -oo: e0 = e.subs(z, -z) else: if str(dir) == "-": e0 = e.subs(z, z0 - 1/z) elif str(dir) == "+": e0 = e.subs(z, z0 + 1/z) else: raise NotImplementedError("dir must be '+' or '-'") try: r = limitinf(e0, z) except ValueError: r = limitinf(e0, z, leadsimp=True) # This is a bit of a heuristic for nice results... we always rewrite # tractable functions in terms of familiar intractable ones. # It might be nicer to rewrite the exactly to what they were initially, # but that would take some work to implement. return r.rewrite('intractable', deep=True)
a5c6d22a9a2fce806bb8a8c6129435c337181e12fba25cfd4641fe78f6d937a2
from sympy.core import S, Symbol, Add, sympify, Expr, PoleError, Mul from sympy.core.exprtools import factor_terms from sympy.functions.combinatorial.factorials import factorial from sympy.functions.special.gamma_functions import gamma from sympy.polys import PolynomialError, factor from sympy.series.order import Order from sympy.simplify.ratsimp import ratsimp from sympy.simplify.simplify import together from .gruntz import gruntz def limit(e, z, z0, dir="+"): """Computes the limit of ``e(z)`` at the point ``z0``. Parameters ========== e : expression, the limit of which is to be taken z : symbol representing the variable in the limit. Other symbols are treated as constants. Multivariate limits are not supported. z0 : the value toward which ``z`` tends. Can be any expression, including ``oo`` and ``-oo``. dir : string, optional (default: "+") The limit is bi-directional if ``dir="+-"``, from the right (z->z0+) if ``dir="+"``, and from the left (z->z0-) if ``dir="-"``. For infinite ``z0`` (``oo`` or ``-oo``), the ``dir`` argument is determined from the direction of the infinity (i.e., ``dir="-"`` for ``oo``). Examples ======== >>> from sympy import limit, sin, oo >>> from sympy.abc import x >>> limit(sin(x)/x, x, 0) 1 >>> limit(1/x, x, 0) # default dir='+' oo >>> limit(1/x, x, 0, dir="-") -oo >>> limit(1/x, x, 0, dir='+-') zoo >>> limit(1/x, x, oo) 0 Notes ===== First we try some heuristics for easy and frequent cases like "x", "1/x", "x**2" and similar, so that it's fast. For all other cases, we use the Gruntz algorithm (see the gruntz() function). See Also ======== limit_seq : returns the limit of a sequence. """ return Limit(e, z, z0, dir).doit(deep=False) def heuristics(e, z, z0, dir): """Computes the limit of an expression term-wise. Parameters are the same as for the ``limit`` function. Works with the arguments of expression ``e`` one by one, computing the limit of each and then combining the results. This approach works only for simple limits, but it is fast. """ from sympy.calculus.util import AccumBounds rv = None if abs(z0) is S.Infinity: rv = limit(e.subs(z, 1/z), z, S.Zero, "+" if z0 is S.Infinity else "-") if isinstance(rv, Limit): return elif e.is_Mul or e.is_Add or e.is_Pow or e.is_Function: r = [] for a in e.args: l = limit(a, z, z0, dir) if l.has(S.Infinity) and l.is_finite is None: if isinstance(e, Add): m = factor_terms(e) if not isinstance(m, Mul): # try together m = together(m) if not isinstance(m, Mul): # try factor if the previous methods failed m = factor(e) if isinstance(m, Mul): return heuristics(m, z, z0, dir) return return elif isinstance(l, Limit): return elif l is S.NaN: return else: r.append(l) if r: rv = e.func(*r) if rv is S.NaN and e.is_Mul and any(isinstance(rr, AccumBounds) for rr in r): r2 = [] e2 = [] for ii in range(len(r)): if isinstance(r[ii], AccumBounds): r2.append(r[ii]) else: e2.append(e.args[ii]) if len(e2) > 0: e3 = Mul(*e2).simplify() l = limit(e3, z, z0, dir) rv = l * Mul(*r2) if rv is S.NaN: try: rat_e = ratsimp(e) except PolynomialError: return if rat_e is S.NaN or rat_e == e: return return limit(rat_e, z, z0, dir) return rv class Limit(Expr): """Represents an unevaluated limit. Examples ======== >>> from sympy import Limit, sin >>> from sympy.abc import x >>> Limit(sin(x)/x, x, 0) Limit(sin(x)/x, x, 0) >>> Limit(1/x, x, 0, dir="-") Limit(1/x, x, 0, dir='-') """ def __new__(cls, e, z, z0, dir="+"): e = sympify(e) z = sympify(z) z0 = sympify(z0) if z0 is S.Infinity: dir = "-" elif z0 is S.NegativeInfinity: dir = "+" if(z0.has(z)): raise NotImplementedError("Limits approaching a variable point are" " not supported (%s -> %s)" % (z, z0)) if isinstance(dir, str): dir = Symbol(dir) elif not isinstance(dir, Symbol): raise TypeError("direction must be of type basestring or " "Symbol, not %s" % type(dir)) if str(dir) not in ('+', '-', '+-'): raise ValueError("direction must be one of '+', '-' " "or '+-', not %s" % dir) obj = Expr.__new__(cls) obj._args = (e, z, z0, dir) return obj @property def free_symbols(self): e = self.args[0] isyms = e.free_symbols isyms.difference_update(self.args[1].free_symbols) isyms.update(self.args[2].free_symbols) return isyms def pow_heuristics(self): from sympy import exp, log expr, z, z0, _ = self.args b, e = expr.base, expr.exp if not b.has(z): res = limit(e*log(b), z, z0) return exp(res) ex_lim = limit(e, z, z0) base_lim = limit(b, z, z0) if base_lim is S.One: if ex_lim in (S.Infinity, S.NegativeInfinity): res = limit(e*(b - 1), z, z0) return exp(res) if base_lim is S.NegativeInfinity and ex_lim is S.Infinity: return S.ComplexInfinity def doit(self, **hints): """Evaluates the limit. Parameters ========== deep : bool, optional (default: True) Invoke the ``doit`` method of the expressions involved before taking the limit. hints : optional keyword arguments To be passed to ``doit`` methods; only used if deep is True. """ from sympy import Abs, sign e, z, z0, dir = self.args if z0 is S.ComplexInfinity: raise NotImplementedError("Limits at complex " "infinity are not implemented") if hints.get('deep', True): e = e.doit(**hints) z = z.doit(**hints) z0 = z0.doit(**hints) if e == z: return z0 if not e.has(z): return e if z0 is S.NaN: return S.NaN if e.has(S.Infinity, S.NegativeInfinity, S.ComplexInfinity, S.NaN): return self if e.is_Order: return Order(limit(e.expr, z, z0), *e.args[1:]) cdir = 0 if str(dir) == "+": cdir = 1 elif str(dir) == "-": cdir = -1 def set_signs(expr): if not expr.args: return expr newargs = tuple(set_signs(arg) for arg in expr.args) if newargs != expr.args: expr = expr.func(*newargs) abs_flag = isinstance(expr, Abs) sign_flag = isinstance(expr, sign) if abs_flag or sign_flag: sig = limit(expr.args[0], z, z0, dir) if sig.is_zero: sig = limit(1/expr.args[0], z, z0, dir) if sig.is_extended_real: if (sig < 0) == True: return -expr.args[0] if abs_flag else S.NegativeOne elif (sig > 0) == True: return expr.args[0] if abs_flag else S.One return expr e = set_signs(e) if e.is_meromorphic(z, z0): if abs(z0) is S.Infinity: newe = e.subs(z, -1/z) else: newe = e.subs(z, z + z0) try: coeff, ex = newe.leadterm(z, cdir=cdir) except ValueError: pass else: if ex > 0: return S.Zero elif ex == 0: return coeff if str(dir) == "+" or not(int(ex) & 1): return S.Infinity*sign(coeff) elif str(dir) == "-": return S.NegativeInfinity*sign(coeff) else: return S.ComplexInfinity if abs(z0) is S.Infinity: if e.is_Mul: e = factor_terms(e) newe = e.subs(z, 1/z) # cdir changes sign as oo- should become 0+ cdir = -cdir else: newe = e.subs(z, z + z0) try: coeff, ex = newe.leadterm(z, cdir=cdir) except (ValueError, NotImplementedError, PoleError): # The NotImplementedError catching is for custom functions if e.is_Pow: r = self.pow_heuristics() if r is not None: return r else: if coeff.has(S.Infinity, S.NegativeInfinity, S.ComplexInfinity): return self if not coeff.has(z): if ex.is_positive: return S.Zero elif ex == 0: return coeff elif ex.is_negative: if ex.is_integer: if str(dir) == "-" or ex.is_even: return S.Infinity*sign(coeff) elif str(dir) == "+": return S.NegativeInfinity*sign(coeff) else: return S.ComplexInfinity else: if str(dir) == "+": return S.Infinity*sign(coeff) elif str(dir) == "-": return S.NegativeInfinity*sign(coeff)*S.NegativeOne**(S.One + ex) else: return S.ComplexInfinity # gruntz fails on factorials but works with the gamma function # If no factorial term is present, e should remain unchanged. # factorial is defined to be zero for negative inputs (which # differs from gamma) so only rewrite for positive z0. if z0.is_extended_positive: e = e.rewrite(factorial, gamma) l = None try: if str(dir) == '+-': r = gruntz(e, z, z0, '+') l = gruntz(e, z, z0, '-') if l != r: raise ValueError("The limit does not exist since " "left hand limit = %s and right hand limit = %s" % (l, r)) else: r = gruntz(e, z, z0, dir) if r is S.NaN or l is S.NaN: raise PoleError() except (PoleError, ValueError): if l is not None: raise r = heuristics(e, z, z0, dir) if r is None: return self return r
e7a95cc40e376044a2476df78257c480c8d0a523e6b7dafa3b7573de8fb7d782
"""Fourier Series""" from sympy import pi, oo, Wild from sympy.core.expr import Expr from sympy.core.add import Add from sympy.core.compatibility import is_sequence from sympy.core.containers import Tuple from sympy.core.singleton import S from sympy.core.symbol import Dummy, Symbol from sympy.core.sympify import sympify from sympy.functions.elementary.trigonometric import sin, cos, sinc from sympy.series.series_class import SeriesBase from sympy.series.sequences import SeqFormula from sympy.sets.sets import Interval from sympy.simplify.fu import TR2, TR1, TR10, sincos_to_sum def fourier_cos_seq(func, limits, n): """Returns the cos sequence in a Fourier series""" from sympy.integrals import integrate x, L = limits[0], limits[2] - limits[1] cos_term = cos(2*n*pi*x / L) formula = 2 * cos_term * integrate(func * cos_term, limits) / L a0 = formula.subs(n, S.Zero) / 2 return a0, SeqFormula(2 * cos_term * integrate(func * cos_term, limits) / L, (n, 1, oo)) def fourier_sin_seq(func, limits, n): """Returns the sin sequence in a Fourier series""" from sympy.integrals import integrate x, L = limits[0], limits[2] - limits[1] sin_term = sin(2*n*pi*x / L) return SeqFormula(2 * sin_term * integrate(func * sin_term, limits) / L, (n, 1, oo)) def _process_limits(func, limits): """ Limits should be of the form (x, start, stop). x should be a symbol. Both start and stop should be bounded. Explanation =========== * If x is not given, x is determined from func. * If limits is None. Limit of the form (x, -pi, pi) is returned. Examples ======== >>> from sympy.series.fourier import _process_limits as pari >>> from sympy.abc import x >>> pari(x**2, (x, -2, 2)) (x, -2, 2) >>> pari(x**2, (-2, 2)) (x, -2, 2) >>> pari(x**2, None) (x, -pi, pi) """ def _find_x(func): free = func.free_symbols if len(free) == 1: return free.pop() elif not free: return Dummy('k') else: raise ValueError( " specify dummy variables for %s. If the function contains" " more than one free symbol, a dummy variable should be" " supplied explicitly e.g. FourierSeries(m*n**2, (n, -pi, pi))" % func) x, start, stop = None, None, None if limits is None: x, start, stop = _find_x(func), -pi, pi if is_sequence(limits, Tuple): if len(limits) == 3: x, start, stop = limits elif len(limits) == 2: x = _find_x(func) start, stop = limits if not isinstance(x, Symbol) or start is None or stop is None: raise ValueError('Invalid limits given: %s' % str(limits)) unbounded = [S.NegativeInfinity, S.Infinity] if start in unbounded or stop in unbounded: raise ValueError("Both the start and end value should be bounded") return sympify((x, start, stop)) def finite_check(f, x, L): def check_fx(exprs, x): return x not in exprs.free_symbols def check_sincos(_expr, x, L): if isinstance(_expr, (sin, cos)): sincos_args = _expr.args[0] if sincos_args.match(a*(pi/L)*x + b) is not None: return True else: return False _expr = sincos_to_sum(TR2(TR1(f))) add_coeff = _expr.as_coeff_add() a = Wild('a', properties=[lambda k: k.is_Integer, lambda k: k != S.Zero, ]) b = Wild('b', properties=[lambda k: x not in k.free_symbols, ]) for s in add_coeff[1]: mul_coeffs = s.as_coeff_mul()[1] for t in mul_coeffs: if not (check_fx(t, x) or check_sincos(t, x, L)): return False, f return True, _expr class FourierSeries(SeriesBase): r"""Represents Fourier sine/cosine series. Explanation =========== This class only represents a fourier series. No computation is performed. For how to compute Fourier series, see the :func:`fourier_series` docstring. See Also ======== sympy.series.fourier.fourier_series """ def __new__(cls, *args): args = map(sympify, args) return Expr.__new__(cls, *args) @property def function(self): return self.args[0] @property def x(self): return self.args[1][0] @property def period(self): return (self.args[1][1], self.args[1][2]) @property def a0(self): return self.args[2][0] @property def an(self): return self.args[2][1] @property def bn(self): return self.args[2][2] @property def interval(self): return Interval(0, oo) @property def start(self): return self.interval.inf @property def stop(self): return self.interval.sup @property def length(self): return oo @property def L(self): return abs(self.period[1] - self.period[0]) / 2 def _eval_subs(self, old, new): x = self.x if old.has(x): return self def truncate(self, n=3): """ Return the first n nonzero terms of the series. If ``n`` is None return an iterator. Parameters ========== n : int or None Amount of non-zero terms in approximation or None. Returns ======= Expr or iterator : Approximation of function expanded into Fourier series. Examples ======== >>> from sympy import fourier_series, pi >>> from sympy.abc import x >>> s = fourier_series(x, (x, -pi, pi)) >>> s.truncate(4) 2*sin(x) - sin(2*x) + 2*sin(3*x)/3 - sin(4*x)/2 See Also ======== sympy.series.fourier.FourierSeries.sigma_approximation """ if n is None: return iter(self) terms = [] for t in self: if len(terms) == n: break if t is not S.Zero: terms.append(t) return Add(*terms) def sigma_approximation(self, n=3): r""" Return :math:`\sigma`-approximation of Fourier series with respect to order n. Explanation =========== Sigma approximation adjusts a Fourier summation to eliminate the Gibbs phenomenon which would otherwise occur at discontinuities. A sigma-approximated summation for a Fourier series of a T-periodical function can be written as .. math:: s(\theta) = \frac{1}{2} a_0 + \sum _{k=1}^{m-1} \operatorname{sinc} \Bigl( \frac{k}{m} \Bigr) \cdot \left[ a_k \cos \Bigl( \frac{2\pi k}{T} \theta \Bigr) + b_k \sin \Bigl( \frac{2\pi k}{T} \theta \Bigr) \right], where :math:`a_0, a_k, b_k, k=1,\ldots,{m-1}` are standard Fourier series coefficients and :math:`\operatorname{sinc} \Bigl( \frac{k}{m} \Bigr)` is a Lanczos :math:`\sigma` factor (expressed in terms of normalized :math:`\operatorname{sinc}` function). Parameters ========== n : int Highest order of the terms taken into account in approximation. Returns ======= Expr : Sigma approximation of function expanded into Fourier series. Examples ======== >>> from sympy import fourier_series, pi >>> from sympy.abc import x >>> s = fourier_series(x, (x, -pi, pi)) >>> s.sigma_approximation(4) 2*sin(x)*sinc(pi/4) - 2*sin(2*x)/pi + 2*sin(3*x)*sinc(3*pi/4)/3 See Also ======== sympy.series.fourier.FourierSeries.truncate Notes ===== The behaviour of :meth:`~sympy.series.fourier.FourierSeries.sigma_approximation` is different from :meth:`~sympy.series.fourier.FourierSeries.truncate` - it takes all nonzero terms of degree smaller than n, rather than first n nonzero ones. References ========== .. [1] https://en.wikipedia.org/wiki/Gibbs_phenomenon .. [2] https://en.wikipedia.org/wiki/Sigma_approximation """ terms = [sinc(pi * i / n) * t for i, t in enumerate(self[:n]) if t is not S.Zero] return Add(*terms) def shift(self, s): """ Shift the function by a term independent of x. Explanation =========== f(x) -> f(x) + s This is fast, if Fourier series of f(x) is already computed. Examples ======== >>> from sympy import fourier_series, pi >>> from sympy.abc import x >>> s = fourier_series(x**2, (x, -pi, pi)) >>> s.shift(1).truncate() -4*cos(x) + cos(2*x) + 1 + pi**2/3 """ s, x = sympify(s), self.x if x in s.free_symbols: raise ValueError("'%s' should be independent of %s" % (s, x)) a0 = self.a0 + s sfunc = self.function + s return self.func(sfunc, self.args[1], (a0, self.an, self.bn)) def shiftx(self, s): """ Shift x by a term independent of x. Explanation =========== f(x) -> f(x + s) This is fast, if Fourier series of f(x) is already computed. Examples ======== >>> from sympy import fourier_series, pi >>> from sympy.abc import x >>> s = fourier_series(x**2, (x, -pi, pi)) >>> s.shiftx(1).truncate() -4*cos(x + 1) + cos(2*x + 2) + pi**2/3 """ s, x = sympify(s), self.x if x in s.free_symbols: raise ValueError("'%s' should be independent of %s" % (s, x)) an = self.an.subs(x, x + s) bn = self.bn.subs(x, x + s) sfunc = self.function.subs(x, x + s) return self.func(sfunc, self.args[1], (self.a0, an, bn)) def scale(self, s): """ Scale the function by a term independent of x. Explanation =========== f(x) -> s * f(x) This is fast, if Fourier series of f(x) is already computed. Examples ======== >>> from sympy import fourier_series, pi >>> from sympy.abc import x >>> s = fourier_series(x**2, (x, -pi, pi)) >>> s.scale(2).truncate() -8*cos(x) + 2*cos(2*x) + 2*pi**2/3 """ s, x = sympify(s), self.x if x in s.free_symbols: raise ValueError("'%s' should be independent of %s" % (s, x)) an = self.an.coeff_mul(s) bn = self.bn.coeff_mul(s) a0 = self.a0 * s sfunc = self.args[0] * s return self.func(sfunc, self.args[1], (a0, an, bn)) def scalex(self, s): """ Scale x by a term independent of x. Explanation =========== f(x) -> f(s*x) This is fast, if Fourier series of f(x) is already computed. Examples ======== >>> from sympy import fourier_series, pi >>> from sympy.abc import x >>> s = fourier_series(x**2, (x, -pi, pi)) >>> s.scalex(2).truncate() -4*cos(2*x) + cos(4*x) + pi**2/3 """ s, x = sympify(s), self.x if x in s.free_symbols: raise ValueError("'%s' should be independent of %s" % (s, x)) an = self.an.subs(x, x * s) bn = self.bn.subs(x, x * s) sfunc = self.function.subs(x, x * s) return self.func(sfunc, self.args[1], (self.a0, an, bn)) def _eval_as_leading_term(self, x, logx=None, cdir=0): for t in self: if t is not S.Zero: return t def _eval_term(self, pt): if pt == 0: return self.a0 return self.an.coeff(pt) + self.bn.coeff(pt) def __neg__(self): return self.scale(-1) def __add__(self, other): if isinstance(other, FourierSeries): if self.period != other.period: raise ValueError("Both the series should have same periods") x, y = self.x, other.x function = self.function + other.function.subs(y, x) if self.x not in function.free_symbols: return function an = self.an + other.an bn = self.bn + other.bn a0 = self.a0 + other.a0 return self.func(function, self.args[1], (a0, an, bn)) return Add(self, other) def __sub__(self, other): return self.__add__(-other) class FiniteFourierSeries(FourierSeries): r"""Represents Finite Fourier sine/cosine series. For how to compute Fourier series, see the :func:`fourier_series` docstring. Parameters ========== f : Expr Expression for finding fourier_series limits : ( x, start, stop) x is the independent variable for the expression f (start, stop) is the period of the fourier series exprs: (a0, an, bn) or Expr a0 is the constant term a0 of the fourier series an is a dictionary of coefficients of cos terms an[k] = coefficient of cos(pi*(k/L)*x) bn is a dictionary of coefficients of sin terms bn[k] = coefficient of sin(pi*(k/L)*x) or exprs can be an expression to be converted to fourier form Methods ======= This class is an extension of FourierSeries class. Please refer to sympy.series.fourier.FourierSeries for further information. See Also ======== sympy.series.fourier.FourierSeries sympy.series.fourier.fourier_series """ def __new__(cls, f, limits, exprs): f = sympify(f) limits = sympify(limits) exprs = sympify(exprs) if not (type(exprs) == Tuple and len(exprs) == 3): # exprs is not of form (a0, an, bn) # Converts the expression to fourier form c, e = exprs.as_coeff_add() rexpr = c + Add(*[TR10(i) for i in e]) a0, exp_ls = rexpr.expand(trig=False, power_base=False, power_exp=False, log=False).as_coeff_add() x = limits[0] L = abs(limits[2] - limits[1]) / 2 a = Wild('a', properties=[lambda k: k.is_Integer, lambda k: k is not S.Zero, ]) b = Wild('b', properties=[lambda k: x not in k.free_symbols, ]) an = dict() bn = dict() # separates the coefficients of sin and cos terms in dictionaries an, and bn for p in exp_ls: t = p.match(b * cos(a * (pi / L) * x)) q = p.match(b * sin(a * (pi / L) * x)) if t: an[t[a]] = t[b] + an.get(t[a], S.Zero) elif q: bn[q[a]] = q[b] + bn.get(q[a], S.Zero) else: a0 += p exprs = Tuple(a0, an, bn) return Expr.__new__(cls, f, limits, exprs) @property def interval(self): _length = 1 if self.a0 else 0 _length += max(set(self.an.keys()).union(set(self.bn.keys()))) + 1 return Interval(0, _length) @property def length(self): return self.stop - self.start def shiftx(self, s): s, x = sympify(s), self.x if x in s.free_symbols: raise ValueError("'%s' should be independent of %s" % (s, x)) _expr = self.truncate().subs(x, x + s) sfunc = self.function.subs(x, x + s) return self.func(sfunc, self.args[1], _expr) def scale(self, s): s, x = sympify(s), self.x if x in s.free_symbols: raise ValueError("'%s' should be independent of %s" % (s, x)) _expr = self.truncate() * s sfunc = self.function * s return self.func(sfunc, self.args[1], _expr) def scalex(self, s): s, x = sympify(s), self.x if x in s.free_symbols: raise ValueError("'%s' should be independent of %s" % (s, x)) _expr = self.truncate().subs(x, x * s) sfunc = self.function.subs(x, x * s) return self.func(sfunc, self.args[1], _expr) def _eval_term(self, pt): if pt == 0: return self.a0 _term = self.an.get(pt, S.Zero) * cos(pt * (pi / self.L) * self.x) \ + self.bn.get(pt, S.Zero) * sin(pt * (pi / self.L) * self.x) return _term def __add__(self, other): if isinstance(other, FourierSeries): return other.__add__(fourier_series(self.function, self.args[1],\ finite=False)) elif isinstance(other, FiniteFourierSeries): if self.period != other.period: raise ValueError("Both the series should have same periods") x, y = self.x, other.x function = self.function + other.function.subs(y, x) if self.x not in function.free_symbols: return function return fourier_series(function, limits=self.args[1]) def fourier_series(f, limits=None, finite=True): r"""Computes the Fourier trigonometric series expansion. Explanation =========== Fourier trigonometric series of $f(x)$ over the interval $(a, b)$ is defined as: .. math:: \frac{a_0}{2} + \sum_{n=1}^{\infty} (a_n \cos(\frac{2n \pi x}{L}) + b_n \sin(\frac{2n \pi x}{L})) where the coefficients are: .. math:: L = b - a .. math:: a_0 = \frac{2}{L} \int_{a}^{b}{f(x) dx} .. math:: a_n = \frac{2}{L} \int_{a}^{b}{f(x) \cos(\frac{2n \pi x}{L}) dx} .. math:: b_n = \frac{2}{L} \int_{a}^{b}{f(x) \sin(\frac{2n \pi x}{L}) dx} The condition whether the function $f(x)$ given should be periodic or not is more than necessary, because it is sufficient to consider the series to be converging to $f(x)$ only in the given interval, not throughout the whole real line. This also brings a lot of ease for the computation because you don't have to make $f(x)$ artificially periodic by wrapping it with piecewise, modulo operations, but you can shape the function to look like the desired periodic function only in the interval $(a, b)$, and the computed series will automatically become the series of the periodic version of $f(x)$. This property is illustrated in the examples section below. Parameters ========== limits : (sym, start, end), optional *sym* denotes the symbol the series is computed with respect to. *start* and *end* denotes the start and the end of the interval where the fourier series converges to the given function. Default range is specified as $-\pi$ and $\pi$. Returns ======= FourierSeries A symbolic object representing the Fourier trigonometric series. Examples ======== Computing the Fourier series of $f(x) = x^2$: >>> from sympy import fourier_series, pi >>> from sympy.abc import x >>> f = x**2 >>> s = fourier_series(f, (x, -pi, pi)) >>> s1 = s.truncate(n=3) >>> s1 -4*cos(x) + cos(2*x) + pi**2/3 Shifting of the Fourier series: >>> s.shift(1).truncate() -4*cos(x) + cos(2*x) + 1 + pi**2/3 >>> s.shiftx(1).truncate() -4*cos(x + 1) + cos(2*x + 2) + pi**2/3 Scaling of the Fourier series: >>> s.scale(2).truncate() -8*cos(x) + 2*cos(2*x) + 2*pi**2/3 >>> s.scalex(2).truncate() -4*cos(2*x) + cos(4*x) + pi**2/3 Computing the Fourier series of $f(x) = x$: This illustrates how truncating to the higher order gives better convergence. .. plot:: :context: reset :format: doctest :include-source: True >>> from sympy import fourier_series, pi, plot >>> from sympy.abc import x >>> f = x >>> s = fourier_series(f, (x, -pi, pi)) >>> s1 = s.truncate(n = 3) >>> s2 = s.truncate(n = 5) >>> s3 = s.truncate(n = 7) >>> p = plot(f, s1, s2, s3, (x, -pi, pi), show=False, legend=True) >>> p[0].line_color = (0, 0, 0) >>> p[0].label = 'x' >>> p[1].line_color = (0.7, 0.7, 0.7) >>> p[1].label = 'n=3' >>> p[2].line_color = (0.5, 0.5, 0.5) >>> p[2].label = 'n=5' >>> p[3].line_color = (0.3, 0.3, 0.3) >>> p[3].label = 'n=7' >>> p.show() This illustrates how the series converges to different sawtooth waves if the different ranges are specified. .. plot:: :context: close-figs :format: doctest :include-source: True >>> s1 = fourier_series(x, (x, -1, 1)).truncate(10) >>> s2 = fourier_series(x, (x, -pi, pi)).truncate(10) >>> s3 = fourier_series(x, (x, 0, 1)).truncate(10) >>> p = plot(x, s1, s2, s3, (x, -5, 5), show=False, legend=True) >>> p[0].line_color = (0, 0, 0) >>> p[0].label = 'x' >>> p[1].line_color = (0.7, 0.7, 0.7) >>> p[1].label = '[-1, 1]' >>> p[2].line_color = (0.5, 0.5, 0.5) >>> p[2].label = '[-pi, pi]' >>> p[3].line_color = (0.3, 0.3, 0.3) >>> p[3].label = '[0, 1]' >>> p.show() Notes ===== Computing Fourier series can be slow due to the integration required in computing an, bn. It is faster to compute Fourier series of a function by using shifting and scaling on an already computed Fourier series rather than computing again. e.g. If the Fourier series of ``x**2`` is known the Fourier series of ``x**2 - 1`` can be found by shifting by ``-1``. See Also ======== sympy.series.fourier.FourierSeries References ========== .. [1] https://mathworld.wolfram.com/FourierSeries.html """ f = sympify(f) limits = _process_limits(f, limits) x = limits[0] if x not in f.free_symbols: return f if finite: L = abs(limits[2] - limits[1]) / 2 is_finite, res_f = finite_check(f, x, L) if is_finite: return FiniteFourierSeries(f, limits, res_f) n = Dummy('n') center = (limits[1] + limits[2]) / 2 if center.is_zero: neg_f = f.subs(x, -x) if f == neg_f: a0, an = fourier_cos_seq(f, limits, n) bn = SeqFormula(0, (1, oo)) return FourierSeries(f, limits, (a0, an, bn)) elif f == -neg_f: a0 = S.Zero an = SeqFormula(0, (1, oo)) bn = fourier_sin_seq(f, limits, n) return FourierSeries(f, limits, (a0, an, bn)) a0, an = fourier_cos_seq(f, limits, n) bn = fourier_sin_seq(f, limits, n) return FourierSeries(f, limits, (a0, an, bn))
a269480262d4ecccee7ccdcea42a3afaed83219d8fb0ad2835b02ccb6c9867ec
"""Formal Power Series""" from collections import defaultdict from sympy import oo, zoo, nan from sympy.core.add import Add from sympy.core.compatibility import iterable from sympy.core.expr import Expr from sympy.core.function import Derivative, Function, expand from sympy.core.mul import Mul from sympy.core.numbers import Rational from sympy.core.relational import Eq from sympy.sets.sets import Interval from sympy.core.singleton import S from sympy.core.symbol import Wild, Dummy, symbols, Symbol from sympy.core.sympify import sympify from sympy.discrete.convolutions import convolution from sympy.functions.combinatorial.factorials import binomial, factorial, rf from sympy.functions.combinatorial.numbers import bell from sympy.functions.elementary.integers import floor, frac, ceiling from sympy.functions.elementary.miscellaneous import Min, Max from sympy.functions.elementary.piecewise import Piecewise from sympy.series.limits import Limit from sympy.series.order import Order from sympy.simplify.powsimp import powsimp from sympy.series.sequences import sequence from sympy.series.series_class import SeriesBase def rational_algorithm(f, x, k, order=4, full=False): """ Rational algorithm for computing formula of coefficients of Formal Power Series of a function. Explanation =========== Applicable when f(x) or some derivative of f(x) is a rational function in x. :func:`rational_algorithm` uses :func:`~.apart` function for partial fraction decomposition. :func:`~.apart` by default uses 'undetermined coefficients method'. By setting ``full=True``, 'Bronstein's algorithm' can be used instead. Looks for derivative of a function up to 4'th order (by default). This can be overridden using order option. Parameters ========== x : Symbol order : int, optional Order of the derivative of ``f``, Default is 4. full : bool Returns ======= formula : Expr ind : Expr Independent terms. order : int full : bool Examples ======== >>> from sympy import log, atan >>> from sympy.series.formal import rational_algorithm as ra >>> from sympy.abc import x, k >>> ra(1 / (1 - x), x, k) (1, 0, 0) >>> ra(log(1 + x), x, k) (-1/((-1)**k*k), 0, 1) >>> ra(atan(x), x, k, full=True) ((-I/(2*(-I)**k) + I/(2*I**k))/k, 0, 1) Notes ===== By setting ``full=True``, range of admissible functions to be solved using ``rational_algorithm`` can be increased. This option should be used carefully as it can significantly slow down the computation as ``doit`` is performed on the :class:`~.RootSum` object returned by the :func:`~.apart` function. Use ``full=False`` whenever possible. See Also ======== sympy.polys.partfrac.apart References ========== .. [1] Formal Power Series - Dominik Gruntz, Wolfram Koepf .. [2] Power Series in Computer Algebra - Wolfram Koepf """ from sympy.polys import RootSum, apart from sympy.integrals import integrate diff = f ds = [] # list of diff for i in range(order + 1): if i: diff = diff.diff(x) if diff.is_rational_function(x): coeff, sep = S.Zero, S.Zero terms = apart(diff, x, full=full) if terms.has(RootSum): terms = terms.doit() for t in Add.make_args(terms): num, den = t.as_numer_denom() if not den.has(x): sep += t else: if isinstance(den, Mul): # m*(n*x - a)**j -> (n*x - a)**j ind = den.as_independent(x) den = ind[1] num /= ind[0] # (n*x - a)**j -> (x - b) den, j = den.as_base_exp() a, xterm = den.as_coeff_add(x) # term -> m/x**n if not a: sep += t continue xc = xterm[0].coeff(x) a /= -xc num /= xc**j ak = ((-1)**j * num * binomial(j + k - 1, k).rewrite(factorial) / a**(j + k)) coeff += ak # Hacky, better way? if coeff.is_zero: return None if (coeff.has(x) or coeff.has(zoo) or coeff.has(oo) or coeff.has(nan)): return None for j in range(i): coeff = (coeff / (k + j + 1)) sep = integrate(sep, x) sep += (ds.pop() - sep).limit(x, 0) # constant of integration return (coeff.subs(k, k - i), sep, i) else: ds.append(diff) return None def rational_independent(terms, x): """ Returns a list of all the rationally independent terms. Examples ======== >>> from sympy import sin, cos >>> from sympy.series.formal import rational_independent >>> from sympy.abc import x >>> rational_independent([cos(x), sin(x)], x) [cos(x), sin(x)] >>> rational_independent([x**2, sin(x), x*sin(x), x**3], x) [x**3 + x**2, x*sin(x) + sin(x)] """ if not terms: return [] ind = terms[0:1] for t in terms[1:]: n = t.as_independent(x)[1] for i, term in enumerate(ind): d = term.as_independent(x)[1] q = (n / d).cancel() if q.is_rational_function(x): ind[i] += t break else: ind.append(t) return ind def simpleDE(f, x, g, order=4): r""" Generates simple DE. Explanation =========== DE is of the form .. math:: f^k(x) + \sum\limits_{j=0}^{k-1} A_j f^j(x) = 0 where :math:`A_j` should be rational function in x. Generates DE's upto order 4 (default). DE's can also have free parameters. By increasing order, higher order DE's can be found. Yields a tuple of (DE, order). """ from sympy.solvers.solveset import linsolve a = symbols('a:%d' % (order)) def _makeDE(k): eq = f.diff(x, k) + Add(*[a[i]*f.diff(x, i) for i in range(0, k)]) DE = g(x).diff(x, k) + Add(*[a[i]*g(x).diff(x, i) for i in range(0, k)]) return eq, DE found = False for k in range(1, order + 1): eq, DE = _makeDE(k) eq = eq.expand() terms = eq.as_ordered_terms() ind = rational_independent(terms, x) if found or len(ind) == k: sol = dict(zip(a, (i for s in linsolve(ind, a[:k]) for i in s))) if sol: found = True DE = DE.subs(sol) DE = DE.as_numer_denom()[0] DE = DE.factor().as_coeff_mul(Derivative)[1][0] yield DE.collect(Derivative(g(x))), k def exp_re(DE, r, k): """Converts a DE with constant coefficients (explike) into a RE. Explanation =========== Performs the substitution: .. math:: f^j(x) \\to r(k + j) Normalises the terms so that lowest order of a term is always r(k). Examples ======== >>> from sympy import Function, Derivative >>> from sympy.series.formal import exp_re >>> from sympy.abc import x, k >>> f, r = Function('f'), Function('r') >>> exp_re(-f(x) + Derivative(f(x)), r, k) -r(k) + r(k + 1) >>> exp_re(Derivative(f(x), x) + Derivative(f(x), (x, 2)), r, k) r(k) + r(k + 1) See Also ======== sympy.series.formal.hyper_re """ RE = S.Zero g = DE.atoms(Function).pop() mini = None for t in Add.make_args(DE): coeff, d = t.as_independent(g) if isinstance(d, Derivative): j = d.derivative_count else: j = 0 if mini is None or j < mini: mini = j RE += coeff * r(k + j) if mini: RE = RE.subs(k, k - mini) return RE def hyper_re(DE, r, k): """ Converts a DE into a RE. Explanation =========== Performs the substitution: .. math:: x^l f^j(x) \\to (k + 1 - l)_j . a_{k + j - l} Normalises the terms so that lowest order of a term is always r(k). Examples ======== >>> from sympy import Function, Derivative >>> from sympy.series.formal import hyper_re >>> from sympy.abc import x, k >>> f, r = Function('f'), Function('r') >>> hyper_re(-f(x) + Derivative(f(x)), r, k) (k + 1)*r(k + 1) - r(k) >>> hyper_re(-x*f(x) + Derivative(f(x), (x, 2)), r, k) (k + 2)*(k + 3)*r(k + 3) - r(k) See Also ======== sympy.series.formal.exp_re """ RE = S.Zero g = DE.atoms(Function).pop() x = g.atoms(Symbol).pop() mini = None for t in Add.make_args(DE.expand()): coeff, d = t.as_independent(g) c, v = coeff.as_independent(x) l = v.as_coeff_exponent(x)[1] if isinstance(d, Derivative): j = d.derivative_count else: j = 0 RE += c * rf(k + 1 - l, j) * r(k + j - l) if mini is None or j - l < mini: mini = j - l RE = RE.subs(k, k - mini) m = Wild('m') return RE.collect(r(k + m)) def _transformation_a(f, x, P, Q, k, m, shift): f *= x**(-shift) P = P.subs(k, k + shift) Q = Q.subs(k, k + shift) return f, P, Q, m def _transformation_c(f, x, P, Q, k, m, scale): f = f.subs(x, x**scale) P = P.subs(k, k / scale) Q = Q.subs(k, k / scale) m *= scale return f, P, Q, m def _transformation_e(f, x, P, Q, k, m): f = f.diff(x) P = P.subs(k, k + 1) * (k + m + 1) Q = Q.subs(k, k + 1) * (k + 1) return f, P, Q, m def _apply_shift(sol, shift): return [(res, cond + shift) for res, cond in sol] def _apply_scale(sol, scale): return [(res, cond / scale) for res, cond in sol] def _apply_integrate(sol, x, k): return [(res / ((cond + 1)*(cond.as_coeff_Add()[1].coeff(k))), cond + 1) for res, cond in sol] def _compute_formula(f, x, P, Q, k, m, k_max): """Computes the formula for f.""" from sympy.polys import roots sol = [] for i in range(k_max + 1, k_max + m + 1): if (i < 0) == True: continue r = f.diff(x, i).limit(x, 0) / factorial(i) if r.is_zero: continue kterm = m*k + i res = r p = P.subs(k, kterm) q = Q.subs(k, kterm) c1 = p.subs(k, 1/k).leadterm(k)[0] c2 = q.subs(k, 1/k).leadterm(k)[0] res *= (-c1 / c2)**k for r, mul in roots(p, k).items(): res *= rf(-r, k)**mul for r, mul in roots(q, k).items(): res /= rf(-r, k)**mul sol.append((res, kterm)) return sol def _rsolve_hypergeometric(f, x, P, Q, k, m): """ Recursive wrapper to rsolve_hypergeometric. Explanation =========== Returns a Tuple of (formula, series independent terms, maximum power of x in independent terms) if successful otherwise ``None``. See :func:`rsolve_hypergeometric` for details. """ from sympy.polys import lcm, roots from sympy.integrals import integrate # transformation - c proots, qroots = roots(P, k), roots(Q, k) all_roots = dict(proots) all_roots.update(qroots) scale = lcm([r.as_numer_denom()[1] for r, t in all_roots.items() if r.is_rational]) f, P, Q, m = _transformation_c(f, x, P, Q, k, m, scale) # transformation - a qroots = roots(Q, k) if qroots: k_min = Min(*qroots.keys()) else: k_min = S.Zero shift = k_min + m f, P, Q, m = _transformation_a(f, x, P, Q, k, m, shift) l = (x*f).limit(x, 0) if not isinstance(l, Limit) and l != 0: # Ideally should only be l != 0 return None qroots = roots(Q, k) if qroots: k_max = Max(*qroots.keys()) else: k_max = S.Zero ind, mp = S.Zero, -oo for i in range(k_max + m + 1): r = f.diff(x, i).limit(x, 0) / factorial(i) if r.is_finite is False: old_f = f f, P, Q, m = _transformation_a(f, x, P, Q, k, m, i) f, P, Q, m = _transformation_e(f, x, P, Q, k, m) sol, ind, mp = _rsolve_hypergeometric(f, x, P, Q, k, m) sol = _apply_integrate(sol, x, k) sol = _apply_shift(sol, i) ind = integrate(ind, x) ind += (old_f - ind).limit(x, 0) # constant of integration mp += 1 return sol, ind, mp elif r: ind += r*x**(i + shift) pow_x = Rational((i + shift), scale) if pow_x > mp: mp = pow_x # maximum power of x ind = ind.subs(x, x**(1/scale)) sol = _compute_formula(f, x, P, Q, k, m, k_max) sol = _apply_shift(sol, shift) sol = _apply_scale(sol, scale) return sol, ind, mp def rsolve_hypergeometric(f, x, P, Q, k, m): """ Solves RE of hypergeometric type. Explanation =========== Attempts to solve RE of the form Q(k)*a(k + m) - P(k)*a(k) Transformations that preserve Hypergeometric type: a. x**n*f(x): b(k + m) = R(k - n)*b(k) b. f(A*x): b(k + m) = A**m*R(k)*b(k) c. f(x**n): b(k + n*m) = R(k/n)*b(k) d. f(x**(1/m)): b(k + 1) = R(k*m)*b(k) e. f'(x): b(k + m) = ((k + m + 1)/(k + 1))*R(k + 1)*b(k) Some of these transformations have been used to solve the RE. Returns ======= formula : Expr ind : Expr Independent terms. order : int Examples ======== >>> from sympy import exp, ln, S >>> from sympy.series.formal import rsolve_hypergeometric as rh >>> from sympy.abc import x, k >>> rh(exp(x), x, -S.One, (k + 1), k, 1) (Piecewise((1/factorial(k), Eq(Mod(k, 1), 0)), (0, True)), 1, 1) >>> rh(ln(1 + x), x, k**2, k*(k + 1), k, 1) (Piecewise(((-1)**(k - 1)*factorial(k - 1)/RisingFactorial(2, k - 1), Eq(Mod(k, 1), 0)), (0, True)), x, 2) References ========== .. [1] Formal Power Series - Dominik Gruntz, Wolfram Koepf .. [2] Power Series in Computer Algebra - Wolfram Koepf """ result = _rsolve_hypergeometric(f, x, P, Q, k, m) if result is None: return None sol_list, ind, mp = result sol_dict = defaultdict(lambda: S.Zero) for res, cond in sol_list: j, mk = cond.as_coeff_Add() c = mk.coeff(k) if j.is_integer is False: res *= x**frac(j) j = floor(j) res = res.subs(k, (k - j) / c) cond = Eq(k % c, j % c) sol_dict[cond] += res # Group together formula for same conditions sol = [] for cond, res in sol_dict.items(): sol.append((res, cond)) sol.append((S.Zero, True)) sol = Piecewise(*sol) if mp is -oo: s = S.Zero elif mp.is_integer is False: s = ceiling(mp) else: s = mp + 1 # save all the terms of # form 1/x**k in ind if s < 0: ind += sum(sequence(sol * x**k, (k, s, -1))) s = S.Zero return (sol, ind, s) def _solve_hyper_RE(f, x, RE, g, k): """See docstring of :func:`rsolve_hypergeometric` for details.""" terms = Add.make_args(RE) if len(terms) == 2: gs = list(RE.atoms(Function)) P, Q = map(RE.coeff, gs) m = gs[1].args[0] - gs[0].args[0] if m < 0: P, Q = Q, P m = abs(m) return rsolve_hypergeometric(f, x, P, Q, k, m) def _solve_explike_DE(f, x, DE, g, k): """Solves DE with constant coefficients.""" from sympy.solvers import rsolve for t in Add.make_args(DE): coeff, d = t.as_independent(g) if coeff.free_symbols: return RE = exp_re(DE, g, k) init = {} for i in range(len(Add.make_args(RE))): if i: f = f.diff(x) init[g(k).subs(k, i)] = f.limit(x, 0) sol = rsolve(RE, g(k), init) if sol: return (sol / factorial(k), S.Zero, S.Zero) def _solve_simple(f, x, DE, g, k): """Converts DE into RE and solves using :func:`rsolve`.""" from sympy.solvers import rsolve RE = hyper_re(DE, g, k) init = {} for i in range(len(Add.make_args(RE))): if i: f = f.diff(x) init[g(k).subs(k, i)] = f.limit(x, 0) / factorial(i) sol = rsolve(RE, g(k), init) if sol: return (sol, S.Zero, S.Zero) def _transform_explike_DE(DE, g, x, order, syms): """Converts DE with free parameters into DE with constant coefficients.""" from sympy.solvers.solveset import linsolve eq = [] highest_coeff = DE.coeff(Derivative(g(x), x, order)) for i in range(order): coeff = DE.coeff(Derivative(g(x), x, i)) coeff = (coeff / highest_coeff).expand().collect(x) for t in Add.make_args(coeff): eq.append(t) temp = [] for e in eq: if e.has(x): break elif e.has(Symbol): temp.append(e) else: eq = temp if eq: sol = dict(zip(syms, (i for s in linsolve(eq, list(syms)) for i in s))) if sol: DE = DE.subs(sol) DE = DE.factor().as_coeff_mul(Derivative)[1][0] DE = DE.collect(Derivative(g(x))) return DE def _transform_DE_RE(DE, g, k, order, syms): """Converts DE with free parameters into RE of hypergeometric type.""" from sympy.solvers.solveset import linsolve RE = hyper_re(DE, g, k) eq = [] for i in range(1, order): coeff = RE.coeff(g(k + i)) eq.append(coeff) sol = dict(zip(syms, (i for s in linsolve(eq, list(syms)) for i in s))) if sol: m = Wild('m') RE = RE.subs(sol) RE = RE.factor().as_numer_denom()[0].collect(g(k + m)) RE = RE.as_coeff_mul(g)[1][0] for i in range(order): # smallest order should be g(k) if RE.coeff(g(k + i)) and i: RE = RE.subs(k, k - i) break return RE def solve_de(f, x, DE, order, g, k): """ Solves the DE. Explanation =========== Tries to solve DE by either converting into a RE containing two terms or converting into a DE having constant coefficients. Returns ======= formula : Expr ind : Expr Independent terms. order : int Examples ======== >>> from sympy import Derivative as D, Function >>> from sympy import exp, ln >>> from sympy.series.formal import solve_de >>> from sympy.abc import x, k >>> f = Function('f') >>> solve_de(exp(x), x, D(f(x), x) - f(x), 1, f, k) (Piecewise((1/factorial(k), Eq(Mod(k, 1), 0)), (0, True)), 1, 1) >>> solve_de(ln(1 + x), x, (x + 1)*D(f(x), x, 2) + D(f(x)), 2, f, k) (Piecewise(((-1)**(k - 1)*factorial(k - 1)/RisingFactorial(2, k - 1), Eq(Mod(k, 1), 0)), (0, True)), x, 2) """ sol = None syms = DE.free_symbols.difference({g, x}) if syms: RE = _transform_DE_RE(DE, g, k, order, syms) else: RE = hyper_re(DE, g, k) if not RE.free_symbols.difference({k}): sol = _solve_hyper_RE(f, x, RE, g, k) if sol: return sol if syms: DE = _transform_explike_DE(DE, g, x, order, syms) if not DE.free_symbols.difference({x}): sol = _solve_explike_DE(f, x, DE, g, k) if sol: return sol def hyper_algorithm(f, x, k, order=4): """ Hypergeometric algorithm for computing Formal Power Series. Explanation =========== Steps: * Generates DE * Convert the DE into RE * Solves the RE Examples ======== >>> from sympy import exp, ln >>> from sympy.series.formal import hyper_algorithm >>> from sympy.abc import x, k >>> hyper_algorithm(exp(x), x, k) (Piecewise((1/factorial(k), Eq(Mod(k, 1), 0)), (0, True)), 1, 1) >>> hyper_algorithm(ln(1 + x), x, k) (Piecewise(((-1)**(k - 1)*factorial(k - 1)/RisingFactorial(2, k - 1), Eq(Mod(k, 1), 0)), (0, True)), x, 2) See Also ======== sympy.series.formal.simpleDE sympy.series.formal.solve_de """ g = Function('g') des = [] # list of DE's sol = None for DE, i in simpleDE(f, x, g, order): if DE is not None: sol = solve_de(f, x, DE, i, g, k) if sol: return sol if not DE.free_symbols.difference({x}): des.append(DE) # If nothing works # Try plain rsolve for DE in des: sol = _solve_simple(f, x, DE, g, k) if sol: return sol def _compute_fps(f, x, x0, dir, hyper, order, rational, full): """Recursive wrapper to compute fps. See :func:`compute_fps` for details. """ if x0 in [S.Infinity, S.NegativeInfinity]: dir = S.One if x0 is S.Infinity else -S.One temp = f.subs(x, 1/x) result = _compute_fps(temp, x, 0, dir, hyper, order, rational, full) if result is None: return None return (result[0], result[1].subs(x, 1/x), result[2].subs(x, 1/x)) elif x0 or dir == -S.One: if dir == -S.One: rep = -x + x0 rep2 = -x rep2b = x0 else: rep = x + x0 rep2 = x rep2b = -x0 temp = f.subs(x, rep) result = _compute_fps(temp, x, 0, S.One, hyper, order, rational, full) if result is None: return None return (result[0], result[1].subs(x, rep2 + rep2b), result[2].subs(x, rep2 + rep2b)) if f.is_polynomial(x): k = Dummy('k') ak = sequence(Coeff(f, x, k), (k, 1, oo)) xk = sequence(x**k, (k, 0, oo)) ind = f.coeff(x, 0) return ak, xk, ind # Break instances of Add # this allows application of different # algorithms on different terms increasing the # range of admissible functions. if isinstance(f, Add): result = False ak = sequence(S.Zero, (0, oo)) ind, xk = S.Zero, None for t in Add.make_args(f): res = _compute_fps(t, x, 0, S.One, hyper, order, rational, full) if res: if not result: result = True xk = res[1] if res[0].start > ak.start: seq = ak s, f = ak.start, res[0].start else: seq = res[0] s, f = res[0].start, ak.start save = Add(*[z[0]*z[1] for z in zip(seq[0:(f - s)], xk[s:f])]) ak += res[0] ind += res[2] + save else: ind += t if result: return ak, xk, ind return None # The symbolic term - symb, if present, is being separated from the function # Otherwise symb is being set to S.One syms = f.free_symbols.difference({x}) (f, symb) = expand(f).as_independent(*syms) if symb.is_zero: symb = S.One symb = powsimp(symb) result = None # from here on it's x0=0 and dir=1 handling k = Dummy('k') if rational: result = rational_algorithm(f, x, k, order, full) if result is None and hyper: result = hyper_algorithm(f, x, k, order) if result is None: return None ak = sequence(result[0], (k, result[2], oo)) xk_formula = powsimp(x**k * symb) xk = sequence(xk_formula, (k, 0, oo)) ind = powsimp(result[1] * symb) return ak, xk, ind def compute_fps(f, x, x0=0, dir=1, hyper=True, order=4, rational=True, full=False): """ Computes the formula for Formal Power Series of a function. Explanation =========== Tries to compute the formula by applying the following techniques (in order): * rational_algorithm * Hypergeometric algorithm Parameters ========== x : Symbol x0 : number, optional Point to perform series expansion about. Default is 0. dir : {1, -1, '+', '-'}, optional If dir is 1 or '+' the series is calculated from the right and for -1 or '-' the series is calculated from the left. For smooth functions this flag will not alter the results. Default is 1. hyper : {True, False}, optional Set hyper to False to skip the hypergeometric algorithm. By default it is set to False. order : int, optional Order of the derivative of ``f``, Default is 4. rational : {True, False}, optional Set rational to False to skip rational algorithm. By default it is set to True. full : {True, False}, optional Set full to True to increase the range of rational algorithm. See :func:`rational_algorithm` for details. By default it is set to False. Returns ======= ak : sequence Sequence of coefficients. xk : sequence Sequence of powers of x. ind : Expr Independent terms. mul : Pow Common terms. See Also ======== sympy.series.formal.rational_algorithm sympy.series.formal.hyper_algorithm """ f = sympify(f) x = sympify(x) if not f.has(x): return None x0 = sympify(x0) if dir == '+': dir = S.One elif dir == '-': dir = -S.One elif dir not in [S.One, -S.One]: raise ValueError("Dir must be '+' or '-'") else: dir = sympify(dir) return _compute_fps(f, x, x0, dir, hyper, order, rational, full) class Coeff(Function): """ Coeff(p, x, n) represents the nth coefficient of the polynomial p in x """ @classmethod def eval(cls, p, x, n): if p.is_polynomial(x) and n.is_integer: return p.coeff(x, n) class FormalPowerSeries(SeriesBase): """ Represents Formal Power Series of a function. Explanation =========== No computation is performed. This class should only to be used to represent a series. No checks are performed. For computing a series use :func:`fps`. See Also ======== sympy.series.formal.fps """ def __new__(cls, *args): args = map(sympify, args) return Expr.__new__(cls, *args) def __init__(self, *args): ak = args[4][0] k = ak.variables[0] self.ak_seq = sequence(ak.formula, (k, 1, oo)) self.fact_seq = sequence(factorial(k), (k, 1, oo)) self.bell_coeff_seq = self.ak_seq * self.fact_seq self.sign_seq = sequence((-1, 1), (k, 1, oo)) @property def function(self): return self.args[0] @property def x(self): return self.args[1] @property def x0(self): return self.args[2] @property def dir(self): return self.args[3] @property def ak(self): return self.args[4][0] @property def xk(self): return self.args[4][1] @property def ind(self): return self.args[4][2] @property def interval(self): return Interval(0, oo) @property def start(self): return self.interval.inf @property def stop(self): return self.interval.sup @property def length(self): return oo @property def infinite(self): """Returns an infinite representation of the series""" from sympy.concrete import Sum ak, xk = self.ak, self.xk k = ak.variables[0] inf_sum = Sum(ak.formula * xk.formula, (k, ak.start, ak.stop)) return self.ind + inf_sum def _get_pow_x(self, term): """Returns the power of x in a term.""" xterm, pow_x = term.as_independent(self.x)[1].as_base_exp() if not xterm.has(self.x): return S.Zero return pow_x def polynomial(self, n=6): """ Truncated series as polynomial. Explanation =========== Returns series expansion of ``f`` upto order ``O(x**n)`` as a polynomial(without ``O`` term). """ terms = [] sym = self.free_symbols for i, t in enumerate(self): xp = self._get_pow_x(t) if xp.has(*sym): xp = xp.as_coeff_add(*sym)[0] if xp >= n: break elif xp.is_integer is True and i == n + 1: break elif t is not S.Zero: terms.append(t) return Add(*terms) def truncate(self, n=6): """ Truncated series. Explanation =========== Returns truncated series expansion of f upto order ``O(x**n)``. If n is ``None``, returns an infinite iterator. """ if n is None: return iter(self) x, x0 = self.x, self.x0 pt_xk = self.xk.coeff(n) if x0 is S.NegativeInfinity: x0 = S.Infinity return self.polynomial(n) + Order(pt_xk, (x, x0)) def zero_coeff(self): return self._eval_term(0) def _eval_term(self, pt): try: pt_xk = self.xk.coeff(pt) pt_ak = self.ak.coeff(pt).simplify() # Simplify the coefficients except IndexError: term = S.Zero else: term = (pt_ak * pt_xk) if self.ind: ind = S.Zero sym = self.free_symbols for t in Add.make_args(self.ind): pow_x = self._get_pow_x(t) if pow_x.has(*sym): pow_x = pow_x.as_coeff_add(*sym)[0] if pt == 0 and pow_x < 1: ind += t elif pow_x >= pt and pow_x < pt + 1: ind += t term += ind return term.collect(self.x) def _eval_subs(self, old, new): x = self.x if old.has(x): return self def _eval_as_leading_term(self, x, logx=None, cdir=0): for t in self: if t is not S.Zero: return t def _eval_derivative(self, x): f = self.function.diff(x) ind = self.ind.diff(x) pow_xk = self._get_pow_x(self.xk.formula) ak = self.ak k = ak.variables[0] if ak.formula.has(x): form = [] for e, c in ak.formula.args: temp = S.Zero for t in Add.make_args(e): pow_x = self._get_pow_x(t) temp += t * (pow_xk + pow_x) form.append((temp, c)) form = Piecewise(*form) ak = sequence(form.subs(k, k + 1), (k, ak.start - 1, ak.stop)) else: ak = sequence((ak.formula * pow_xk).subs(k, k + 1), (k, ak.start - 1, ak.stop)) return self.func(f, self.x, self.x0, self.dir, (ak, self.xk, ind)) def integrate(self, x=None, **kwargs): """ Integrate Formal Power Series. Examples ======== >>> from sympy import fps, sin, integrate >>> from sympy.abc import x >>> f = fps(sin(x)) >>> f.integrate(x).truncate() -1 + x**2/2 - x**4/24 + O(x**6) >>> integrate(f, (x, 0, 1)) 1 - cos(1) """ from sympy.integrals import integrate if x is None: x = self.x elif iterable(x): return integrate(self.function, x) f = integrate(self.function, x) ind = integrate(self.ind, x) ind += (f - ind).limit(x, 0) # constant of integration pow_xk = self._get_pow_x(self.xk.formula) ak = self.ak k = ak.variables[0] if ak.formula.has(x): form = [] for e, c in ak.formula.args: temp = S.Zero for t in Add.make_args(e): pow_x = self._get_pow_x(t) temp += t / (pow_xk + pow_x + 1) form.append((temp, c)) form = Piecewise(*form) ak = sequence(form.subs(k, k - 1), (k, ak.start + 1, ak.stop)) else: ak = sequence((ak.formula / (pow_xk + 1)).subs(k, k - 1), (k, ak.start + 1, ak.stop)) return self.func(f, self.x, self.x0, self.dir, (ak, self.xk, ind)) def product(self, other, x=None, n=6): """ Multiplies two Formal Power Series, using discrete convolution and return the truncated terms upto specified order. Parameters ========== n : Number, optional Specifies the order of the term up to which the polynomial should be truncated. Examples ======== >>> from sympy import fps, sin, exp >>> from sympy.abc import x >>> f1 = fps(sin(x)) >>> f2 = fps(exp(x)) >>> f1.product(f2, x).truncate(4) x + x**2 + x**3/3 + O(x**4) See Also ======== sympy.discrete.convolutions sympy.series.formal.FormalPowerSeriesProduct """ if n is None: return iter(self) other = sympify(other) if not isinstance(other, FormalPowerSeries): raise ValueError("Both series should be an instance of FormalPowerSeries" " class.") if self.dir != other.dir: raise ValueError("Both series should be calculated from the" " same direction.") elif self.x0 != other.x0: raise ValueError("Both series should be calculated about the" " same point.") elif self.x != other.x: raise ValueError("Both series should have the same symbol.") return FormalPowerSeriesProduct(self, other) def coeff_bell(self, n): r""" self.coeff_bell(n) returns a sequence of Bell polynomials of the second kind. Note that ``n`` should be a integer. The second kind of Bell polynomials (are sometimes called "partial" Bell polynomials or incomplete Bell polynomials) are defined as .. math:: B_{n,k}(x_1, x_2,\dotsc x_{n-k+1}) = \sum_{j_1+j_2+j_2+\dotsb=k \atop j_1+2j_2+3j_2+\dotsb=n} \frac{n!}{j_1!j_2!\dotsb j_{n-k+1}!} \left(\frac{x_1}{1!} \right)^{j_1} \left(\frac{x_2}{2!} \right)^{j_2} \dotsb \left(\frac{x_{n-k+1}}{(n-k+1)!} \right) ^{j_{n-k+1}}. * ``bell(n, k, (x1, x2, ...))`` gives Bell polynomials of the second kind, `B_{n,k}(x_1, x_2, \dotsc, x_{n-k+1})`. See Also ======== sympy.functions.combinatorial.numbers.bell """ inner_coeffs = [bell(n, j, tuple(self.bell_coeff_seq[:n-j+1])) for j in range(1, n+1)] k = Dummy('k') return sequence(tuple(inner_coeffs), (k, 1, oo)) def compose(self, other, x=None, n=6): r""" Returns the truncated terms of the formal power series of the composed function, up to specified ``n``. Explanation =========== If ``f`` and ``g`` are two formal power series of two different functions, then the coefficient sequence ``ak`` of the composed formal power series `fp` will be as follows. .. math:: \sum\limits_{k=0}^{n} b_k B_{n,k}(x_1, x_2, \dotsc, x_{n-k+1}) Parameters ========== n : Number, optional Specifies the order of the term up to which the polynomial should be truncated. Examples ======== >>> from sympy import fps, sin, exp >>> from sympy.abc import x >>> f1 = fps(exp(x)) >>> f2 = fps(sin(x)) >>> f1.compose(f2, x).truncate() 1 + x + x**2/2 - x**4/8 - x**5/15 + O(x**6) >>> f1.compose(f2, x).truncate(8) 1 + x + x**2/2 - x**4/8 - x**5/15 - x**6/240 + x**7/90 + O(x**8) See Also ======== sympy.functions.combinatorial.numbers.bell sympy.series.formal.FormalPowerSeriesCompose References ========== .. [1] Comtet, Louis: Advanced combinatorics; the art of finite and infinite expansions. Reidel, 1974. """ if n is None: return iter(self) other = sympify(other) if not isinstance(other, FormalPowerSeries): raise ValueError("Both series should be an instance of FormalPowerSeries" " class.") if self.dir != other.dir: raise ValueError("Both series should be calculated from the" " same direction.") elif self.x0 != other.x0: raise ValueError("Both series should be calculated about the" " same point.") elif self.x != other.x: raise ValueError("Both series should have the same symbol.") if other._eval_term(0).as_coeff_mul(other.x)[0] is not S.Zero: raise ValueError("The formal power series of the inner function should not have any " "constant coefficient term.") return FormalPowerSeriesCompose(self, other) def inverse(self, x=None, n=6): r""" Returns the truncated terms of the inverse of the formal power series, up to specified ``n``. Explanation =========== If ``f`` and ``g`` are two formal power series of two different functions, then the coefficient sequence ``ak`` of the composed formal power series ``fp`` will be as follows. .. math:: \sum\limits_{k=0}^{n} (-1)^{k} x_0^{-k-1} B_{n,k}(x_1, x_2, \dotsc, x_{n-k+1}) Parameters ========== n : Number, optional Specifies the order of the term up to which the polynomial should be truncated. Examples ======== >>> from sympy import fps, exp, cos >>> from sympy.abc import x >>> f1 = fps(exp(x)) >>> f2 = fps(cos(x)) >>> f1.inverse(x).truncate() 1 - x + x**2/2 - x**3/6 + x**4/24 - x**5/120 + O(x**6) >>> f2.inverse(x).truncate(8) 1 + x**2/2 + 5*x**4/24 + 61*x**6/720 + O(x**8) See Also ======== sympy.functions.combinatorial.numbers.bell sympy.series.formal.FormalPowerSeriesInverse References ========== .. [1] Comtet, Louis: Advanced combinatorics; the art of finite and infinite expansions. Reidel, 1974. """ if n is None: return iter(self) if self._eval_term(0).is_zero: raise ValueError("Constant coefficient should exist for an inverse of a formal" " power series to exist.") return FormalPowerSeriesInverse(self) def __add__(self, other): other = sympify(other) if isinstance(other, FormalPowerSeries): if self.dir != other.dir: raise ValueError("Both series should be calculated from the" " same direction.") elif self.x0 != other.x0: raise ValueError("Both series should be calculated about the" " same point.") x, y = self.x, other.x f = self.function + other.function.subs(y, x) if self.x not in f.free_symbols: return f ak = self.ak + other.ak if self.ak.start > other.ak.start: seq = other.ak s, e = other.ak.start, self.ak.start else: seq = self.ak s, e = self.ak.start, other.ak.start save = Add(*[z[0]*z[1] for z in zip(seq[0:(e - s)], self.xk[s:e])]) ind = self.ind + other.ind + save return self.func(f, x, self.x0, self.dir, (ak, self.xk, ind)) elif not other.has(self.x): f = self.function + other ind = self.ind + other return self.func(f, self.x, self.x0, self.dir, (self.ak, self.xk, ind)) return Add(self, other) def __radd__(self, other): return self.__add__(other) def __neg__(self): return self.func(-self.function, self.x, self.x0, self.dir, (-self.ak, self.xk, -self.ind)) def __sub__(self, other): return self.__add__(-other) def __rsub__(self, other): return (-self).__add__(other) def __mul__(self, other): other = sympify(other) if other.has(self.x): return Mul(self, other) f = self.function * other ak = self.ak.coeff_mul(other) ind = self.ind * other return self.func(f, self.x, self.x0, self.dir, (ak, self.xk, ind)) def __rmul__(self, other): return self.__mul__(other) class FiniteFormalPowerSeries(FormalPowerSeries): """Base Class for Product, Compose and Inverse classes""" def __init__(self, *args): pass @property def ffps(self): return self.args[0] @property def gfps(self): return self.args[1] @property def f(self): return self.ffps.function @property def g(self): return self.gfps.function @property def infinite(self): raise NotImplementedError("No infinite version for an object of" " FiniteFormalPowerSeries class.") def _eval_terms(self, n): raise NotImplementedError("(%s)._eval_terms()" % self) def _eval_term(self, pt): raise NotImplementedError("By the current logic, one can get terms" "upto a certain order, instead of getting term by term.") def polynomial(self, n): return self._eval_terms(n) def truncate(self, n=6): ffps = self.ffps pt_xk = ffps.xk.coeff(n) x, x0 = ffps.x, ffps.x0 return self.polynomial(n) + Order(pt_xk, (x, x0)) def _eval_derivative(self, x): raise NotImplementedError def integrate(self, x): raise NotImplementedError class FormalPowerSeriesProduct(FiniteFormalPowerSeries): """Represents the product of two formal power series of two functions. Explanation =========== No computation is performed. Terms are calculated using a term by term logic, instead of a point by point logic. There are two differences between a :obj:`FormalPowerSeries` object and a :obj:`FormalPowerSeriesProduct` object. The first argument contains the two functions involved in the product. Also, the coefficient sequence contains both the coefficient sequence of the formal power series of the involved functions. See Also ======== sympy.series.formal.FormalPowerSeries sympy.series.formal.FiniteFormalPowerSeries """ def __init__(self, *args): ffps, gfps = self.ffps, self.gfps k = ffps.ak.variables[0] self.coeff1 = sequence(ffps.ak.formula, (k, 0, oo)) k = gfps.ak.variables[0] self.coeff2 = sequence(gfps.ak.formula, (k, 0, oo)) @property def function(self): """Function of the product of two formal power series.""" return self.f * self.g def _eval_terms(self, n): """ Returns the first ``n`` terms of the product formal power series. Term by term logic is implemented here. Examples ======== >>> from sympy import fps, sin, exp >>> from sympy.abc import x >>> f1 = fps(sin(x)) >>> f2 = fps(exp(x)) >>> fprod = f1.product(f2, x) >>> fprod._eval_terms(4) x**3/3 + x**2 + x See Also ======== sympy.series.formal.FormalPowerSeries.product """ coeff1, coeff2 = self.coeff1, self.coeff2 aks = convolution(coeff1[:n], coeff2[:n]) terms = [] for i in range(0, n): terms.append(aks[i] * self.ffps.xk.coeff(i)) return Add(*terms) class FormalPowerSeriesCompose(FiniteFormalPowerSeries): """ Represents the composed formal power series of two functions. Explanation =========== No computation is performed. Terms are calculated using a term by term logic, instead of a point by point logic. There are two differences between a :obj:`FormalPowerSeries` object and a :obj:`FormalPowerSeriesCompose` object. The first argument contains the outer function and the inner function involved in the omposition. Also, the coefficient sequence contains the generic sequence which is to be multiplied by a custom ``bell_seq`` finite sequence. The finite terms will then be added up to get the final terms. See Also ======== sympy.series.formal.FormalPowerSeries sympy.series.formal.FiniteFormalPowerSeries """ @property def function(self): """Function for the composed formal power series.""" f, g, x = self.f, self.g, self.ffps.x return f.subs(x, g) def _eval_terms(self, n): """ Returns the first `n` terms of the composed formal power series. Term by term logic is implemented here. Explanation =========== The coefficient sequence of the :obj:`FormalPowerSeriesCompose` object is the generic sequence. It is multiplied by ``bell_seq`` to get a sequence, whose terms are added up to get the final terms for the polynomial. Examples ======== >>> from sympy import fps, sin, exp >>> from sympy.abc import x >>> f1 = fps(exp(x)) >>> f2 = fps(sin(x)) >>> fcomp = f1.compose(f2, x) >>> fcomp._eval_terms(6) -x**5/15 - x**4/8 + x**2/2 + x + 1 >>> fcomp._eval_terms(8) x**7/90 - x**6/240 - x**5/15 - x**4/8 + x**2/2 + x + 1 See Also ======== sympy.series.formal.FormalPowerSeries.compose sympy.series.formal.FormalPowerSeries.coeff_bell """ ffps, gfps = self.ffps, self.gfps terms = [ffps.zero_coeff()] for i in range(1, n): bell_seq = gfps.coeff_bell(i) seq = (ffps.bell_coeff_seq * bell_seq) terms.append(Add(*(seq[:i])) / ffps.fact_seq[i-1] * ffps.xk.coeff(i)) return Add(*terms) class FormalPowerSeriesInverse(FiniteFormalPowerSeries): """ Represents the Inverse of a formal power series. Explanation =========== No computation is performed. Terms are calculated using a term by term logic, instead of a point by point logic. There is a single difference between a :obj:`FormalPowerSeries` object and a :obj:`FormalPowerSeriesInverse` object. The coefficient sequence contains the generic sequence which is to be multiplied by a custom ``bell_seq`` finite sequence. The finite terms will then be added up to get the final terms. See Also ======== sympy.series.formal.FormalPowerSeries sympy.series.formal.FiniteFormalPowerSeries """ def __init__(self, *args): ffps = self.ffps k = ffps.xk.variables[0] inv = ffps.zero_coeff() inv_seq = sequence(inv ** (-(k + 1)), (k, 1, oo)) self.aux_seq = ffps.sign_seq * ffps.fact_seq * inv_seq @property def function(self): """Function for the inverse of a formal power series.""" f = self.f return 1 / f @property def g(self): raise ValueError("Only one function is considered while performing" "inverse of a formal power series.") @property def gfps(self): raise ValueError("Only one function is considered while performing" "inverse of a formal power series.") def _eval_terms(self, n): """ Returns the first ``n`` terms of the composed formal power series. Term by term logic is implemented here. Explanation =========== The coefficient sequence of the `FormalPowerSeriesInverse` object is the generic sequence. It is multiplied by ``bell_seq`` to get a sequence, whose terms are added up to get the final terms for the polynomial. Examples ======== >>> from sympy import fps, exp, cos >>> from sympy.abc import x >>> f1 = fps(exp(x)) >>> f2 = fps(cos(x)) >>> finv1, finv2 = f1.inverse(), f2.inverse() >>> finv1._eval_terms(6) -x**5/120 + x**4/24 - x**3/6 + x**2/2 - x + 1 >>> finv2._eval_terms(8) 61*x**6/720 + 5*x**4/24 + x**2/2 + 1 See Also ======== sympy.series.formal.FormalPowerSeries.inverse sympy.series.formal.FormalPowerSeries.coeff_bell """ ffps = self.ffps terms = [ffps.zero_coeff()] for i in range(1, n): bell_seq = ffps.coeff_bell(i) seq = (self.aux_seq * bell_seq) terms.append(Add(*(seq[:i])) / ffps.fact_seq[i-1] * ffps.xk.coeff(i)) return Add(*terms) def fps(f, x=None, x0=0, dir=1, hyper=True, order=4, rational=True, full=False): """ Generates Formal Power Series of ``f``. Explanation =========== Returns the formal series expansion of ``f`` around ``x = x0`` with respect to ``x`` in the form of a ``FormalPowerSeries`` object. Formal Power Series is represented using an explicit formula computed using different algorithms. See :func:`compute_fps` for the more details regarding the computation of formula. Parameters ========== x : Symbol, optional If x is None and ``f`` is univariate, the univariate symbols will be supplied, otherwise an error will be raised. x0 : number, optional Point to perform series expansion about. Default is 0. dir : {1, -1, '+', '-'}, optional If dir is 1 or '+' the series is calculated from the right and for -1 or '-' the series is calculated from the left. For smooth functions this flag will not alter the results. Default is 1. hyper : {True, False}, optional Set hyper to False to skip the hypergeometric algorithm. By default it is set to False. order : int, optional Order of the derivative of ``f``, Default is 4. rational : {True, False}, optional Set rational to False to skip rational algorithm. By default it is set to True. full : {True, False}, optional Set full to True to increase the range of rational algorithm. See :func:`rational_algorithm` for details. By default it is set to False. Examples ======== >>> from sympy import fps, ln, atan, sin >>> from sympy.abc import x, n Rational Functions >>> fps(ln(1 + x)).truncate() x - x**2/2 + x**3/3 - x**4/4 + x**5/5 + O(x**6) >>> fps(atan(x), full=True).truncate() x - x**3/3 + x**5/5 + O(x**6) Symbolic Functions >>> fps(x**n*sin(x**2), x).truncate(8) -x**(n + 6)/6 + x**(n + 2) + O(x**(n + 8)) See Also ======== sympy.series.formal.FormalPowerSeries sympy.series.formal.compute_fps """ f = sympify(f) if x is None: free = f.free_symbols if len(free) == 1: x = free.pop() elif not free: return f else: raise NotImplementedError("multivariate formal power series") result = compute_fps(f, x, x0, dir, hyper, order, rational, full) if result is None: return f return FormalPowerSeries(f, x, x0, dir, result)
6bade01c85157a3a6d40e556656789d1e05d86807abf0c6a0a54e818773435fe
from sympy.core import S, sympify, Expr, Rational, Dummy from sympy.core import Add, Mul, expand_power_base, expand_log from sympy.core.cache import cacheit from sympy.core.compatibility import default_sort_key, is_sequence from sympy.core.containers import Tuple from sympy.sets.sets import Complement from sympy.utilities.iterables import uniq class Order(Expr): r""" Represents the limiting behavior of some function. Explanation =========== The order of a function characterizes the function based on the limiting behavior of the function as it goes to some limit. Only taking the limit point to be a number is currently supported. This is expressed in big O notation [1]_. The formal definition for the order of a function `g(x)` about a point `a` is such that `g(x) = O(f(x))` as `x \rightarrow a` if and only if for any `\delta > 0` there exists a `M > 0` such that `|g(x)| \leq M|f(x)|` for `|x-a| < \delta`. This is equivalent to `\lim_{x \rightarrow a} \sup |g(x)/f(x)| < \infty`. Let's illustrate it on the following example by taking the expansion of `\sin(x)` about 0: .. math :: \sin(x) = x - x^3/3! + O(x^5) where in this case `O(x^5) = x^5/5! - x^7/7! + \cdots`. By the definition of `O`, for any `\delta > 0` there is an `M` such that: .. math :: |x^5/5! - x^7/7! + ....| <= M|x^5| \text{ for } |x| < \delta or by the alternate definition: .. math :: \lim_{x \rightarrow 0} | (x^5/5! - x^7/7! + ....) / x^5| < \infty which surely is true, because .. math :: \lim_{x \rightarrow 0} | (x^5/5! - x^7/7! + ....) / x^5| = 1/5! As it is usually used, the order of a function can be intuitively thought of representing all terms of powers greater than the one specified. For example, `O(x^3)` corresponds to any terms proportional to `x^3, x^4,\ldots` and any higher power. For a polynomial, this leaves terms proportional to `x^2`, `x` and constants. Examples ======== >>> from sympy import O, oo, cos, pi >>> from sympy.abc import x, y >>> O(x + x**2) O(x) >>> O(x + x**2, (x, 0)) O(x) >>> O(x + x**2, (x, oo)) O(x**2, (x, oo)) >>> O(1 + x*y) O(1, x, y) >>> O(1 + x*y, (x, 0), (y, 0)) O(1, x, y) >>> O(1 + x*y, (x, oo), (y, oo)) O(x*y, (x, oo), (y, oo)) >>> O(1) in O(1, x) True >>> O(1, x) in O(1) False >>> O(x) in O(1, x) True >>> O(x**2) in O(x) True >>> O(x)*x O(x**2) >>> O(x) - O(x) O(x) >>> O(cos(x)) O(1) >>> O(cos(x), (x, pi/2)) O(x - pi/2, (x, pi/2)) References ========== .. [1] `Big O notation <https://en.wikipedia.org/wiki/Big_O_notation>`_ Notes ===== In ``O(f(x), x)`` the expression ``f(x)`` is assumed to have a leading term. ``O(f(x), x)`` is automatically transformed to ``O(f(x).as_leading_term(x),x)``. ``O(expr*f(x), x)`` is ``O(f(x), x)`` ``O(expr, x)`` is ``O(1)`` ``O(0, x)`` is 0. Multivariate O is also supported: ``O(f(x, y), x, y)`` is transformed to ``O(f(x, y).as_leading_term(x,y).as_leading_term(y), x, y)`` In the multivariate case, it is assumed the limits w.r.t. the various symbols commute. If no symbols are passed then all symbols in the expression are used and the limit point is assumed to be zero. """ is_Order = True __slots__ = () @cacheit def __new__(cls, expr, *args, **kwargs): expr = sympify(expr) if not args: if expr.is_Order: variables = expr.variables point = expr.point else: variables = list(expr.free_symbols) point = [S.Zero]*len(variables) else: args = list(args if is_sequence(args) else [args]) variables, point = [], [] if is_sequence(args[0]): for a in args: v, p = list(map(sympify, a)) variables.append(v) point.append(p) else: variables = list(map(sympify, args)) point = [S.Zero]*len(variables) if not all(v.is_symbol for v in variables): raise TypeError('Variables are not symbols, got %s' % variables) if len(list(uniq(variables))) != len(variables): raise ValueError('Variables are supposed to be unique symbols, got %s' % variables) if expr.is_Order: expr_vp = dict(expr.args[1:]) new_vp = dict(expr_vp) vp = dict(zip(variables, point)) for v, p in vp.items(): if v in new_vp.keys(): if p != new_vp[v]: raise NotImplementedError( "Mixing Order at different points is not supported.") else: new_vp[v] = p if set(expr_vp.keys()) == set(new_vp.keys()): return expr else: variables = list(new_vp.keys()) point = [new_vp[v] for v in variables] if expr is S.NaN: return S.NaN if any(x in p.free_symbols for x in variables for p in point): raise ValueError('Got %s as a point.' % point) if variables: if any(p != point[0] for p in point): raise NotImplementedError( "Multivariable orders at different points are not supported.") if point[0] is S.Infinity: s = {k: 1/Dummy() for k in variables} rs = {1/v: 1/k for k, v in s.items()} ps = [S.Zero for p in point] elif point[0] is S.NegativeInfinity: s = {k: -1/Dummy() for k in variables} rs = {-1/v: -1/k for k, v in s.items()} ps = [S.Zero for p in point] elif point[0] is not S.Zero: s = {k: Dummy() + point[0] for k in variables} rs = {(v - point[0]).together(): k - point[0] for k, v in s.items()} ps = [S.Zero for p in point] else: s = () rs = () ps = list(point) expr = expr.subs(s) if expr.is_Add: expr = expr.factor() if s: args = tuple([r[0] for r in rs.items()]) else: args = tuple(variables) if len(variables) > 1: # XXX: better way? We need this expand() to # workaround e.g: expr = x*(x + y). # (x*(x + y)).as_leading_term(x, y) currently returns # x*y (wrong order term!). That's why we want to deal with # expand()'ed expr (handled in "if expr.is_Add" branch below). expr = expr.expand() old_expr = None while old_expr != expr: old_expr = expr if expr.is_Add: lst = expr.extract_leading_order(args) expr = Add(*[f.expr for (e, f) in lst]) elif expr: from sympy import PoleError, Function try: expr = expr.as_leading_term(*args) except PoleError: if isinstance(expr, Function) or\ all(isinstance(arg, Function) for arg in expr.args): # It is not possible to simplify an expression # containing only functions (which raise error on # call to leading term) further pass else: orders = [] pts = tuple(zip(args, ps)) for arg in expr.args: try: lt = arg.as_leading_term(*args) except PoleError: lt = arg if lt not in args: order = Order(lt) else: order = Order(lt, *pts) orders.append(order) if expr.is_Add: new_expr = Order(Add(*orders), *pts) if new_expr.is_Add: new_expr = Order(Add(*[a.expr for a in new_expr.args]), *pts) expr = new_expr.expr elif expr.is_Mul: expr = Mul(*[a.expr for a in orders]) elif expr.is_Pow: expr = orders[0].expr**orders[1].expr expr = expr.as_independent(*args, as_Add=False)[1] expr = expand_power_base(expr) expr = expand_log(expr) if len(args) == 1: # The definition of O(f(x)) symbol explicitly stated that # the argument of f(x) is irrelevant. That's why we can # combine some power exponents (only "on top" of the # expression tree for f(x)), e.g.: # x**p * (-x)**q -> x**(p+q) for real p, q. x = args[0] margs = list(Mul.make_args( expr.as_independent(x, as_Add=False)[1])) for i, t in enumerate(margs): if t.is_Pow: b, q = t.args if b in (x, -x) and q.is_real and not q.has(x): margs[i] = x**q elif b.is_Pow and not b.exp.has(x): b, r = b.args if b in (x, -x) and r.is_real: margs[i] = x**(r*q) elif b.is_Mul and b.args[0] is S.NegativeOne: b = -b if b.is_Pow and not b.exp.has(x): b, r = b.args if b in (x, -x) and r.is_real: margs[i] = x**(r*q) expr = Mul(*margs) expr = expr.subs(rs) if expr.is_Order: expr = expr.expr if not expr.has(*variables) and not expr.is_zero: expr = S.One # create Order instance: vp = dict(zip(variables, point)) variables.sort(key=default_sort_key) point = [vp[v] for v in variables] args = (expr,) + Tuple(*zip(variables, point)) obj = Expr.__new__(cls, *args) return obj def _eval_nseries(self, x, n, logx, cdir=0): return self @property def expr(self): return self.args[0] @property def variables(self): if self.args[1:]: return tuple(x[0] for x in self.args[1:]) else: return () @property def point(self): if self.args[1:]: return tuple(x[1] for x in self.args[1:]) else: return () @property def free_symbols(self): return self.expr.free_symbols | set(self.variables) def _eval_power(b, e): if e.is_Number and e.is_nonnegative: return b.func(b.expr ** e, *b.args[1:]) if e == O(1): return b return def as_expr_variables(self, order_symbols): if order_symbols is None: order_symbols = self.args[1:] else: if (not all(o[1] == order_symbols[0][1] for o in order_symbols) and not all(p == self.point[0] for p in self.point)): # pragma: no cover raise NotImplementedError('Order at points other than 0 ' 'or oo not supported, got %s as a point.' % self.point) if order_symbols and order_symbols[0][1] != self.point[0]: raise NotImplementedError( "Multiplying Order at different points is not supported.") order_symbols = dict(order_symbols) for s, p in dict(self.args[1:]).items(): if s not in order_symbols.keys(): order_symbols[s] = p order_symbols = sorted(order_symbols.items(), key=lambda x: default_sort_key(x[0])) return self.expr, tuple(order_symbols) def removeO(self): return S.Zero def getO(self): return self @cacheit def contains(self, expr): r""" Return True if expr belongs to Order(self.expr, \*self.variables). Return False if self belongs to expr. Return None if the inclusion relation cannot be determined (e.g. when self and expr have different symbols). """ from sympy import powsimp if expr.is_zero: return True if expr is S.NaN: return False point = self.point[0] if self.point else S.Zero if expr.is_Order: if (any(p != point for p in expr.point) or any(p != point for p in self.point)): return None if expr.expr == self.expr: # O(1) + O(1), O(1) + O(1, x), etc. return all([x in self.args[1:] for x in expr.args[1:]]) if expr.expr.is_Add: return all([self.contains(x) for x in expr.expr.args]) if self.expr.is_Add and point.is_zero: return any([self.func(x, *self.args[1:]).contains(expr) for x in self.expr.args]) if self.variables and expr.variables: common_symbols = tuple( [s for s in self.variables if s in expr.variables]) elif self.variables: common_symbols = self.variables else: common_symbols = expr.variables if not common_symbols: return None if (self.expr.is_Pow and len(self.variables) == 1 and self.variables == expr.variables): symbol = self.variables[0] other = expr.expr.as_independent(symbol, as_Add=False)[1] if (other.is_Pow and other.base == symbol and self.expr.base == symbol): if point.is_zero: rv = (self.expr.exp - other.exp).is_nonpositive if point.is_infinite: rv = (self.expr.exp - other.exp).is_nonnegative if rv is not None: return rv r = None ratio = self.expr/expr.expr ratio = powsimp(ratio, deep=True, combine='exp') for s in common_symbols: from sympy.series.limits import Limit l = Limit(ratio, s, point).doit(heuristics=False) if not isinstance(l, Limit): l = l != 0 else: l = None if r is None: r = l else: if r != l: return return r if self.expr.is_Pow and len(self.variables) == 1: symbol = self.variables[0] other = expr.as_independent(symbol, as_Add=False)[1] if (other.is_Pow and other.base == symbol and self.expr.base == symbol): if point.is_zero: rv = (self.expr.exp - other.exp).is_nonpositive if point.is_infinite: rv = (self.expr.exp - other.exp).is_nonnegative if rv is not None: return rv obj = self.func(expr, *self.args[1:]) return self.contains(obj) def __contains__(self, other): result = self.contains(other) if result is None: raise TypeError('contains did not evaluate to a bool') return result def _eval_subs(self, old, new): if old in self.variables: newexpr = self.expr.subs(old, new) i = self.variables.index(old) newvars = list(self.variables) newpt = list(self.point) if new.is_symbol: newvars[i] = new else: syms = new.free_symbols if len(syms) == 1 or old in syms: if old in syms: var = self.variables[i] else: var = syms.pop() # First, try to substitute self.point in the "new" # expr to see if this is a fixed point. # E.g. O(y).subs(y, sin(x)) point = new.subs(var, self.point[i]) if point != self.point[i]: from sympy.solvers.solveset import solveset d = Dummy() sol = solveset(old - new.subs(var, d), d) if isinstance(sol, Complement): e1 = sol.args[0] e2 = sol.args[1] sol = set(e1) - set(e2) res = [dict(zip((d, ), sol))] point = d.subs(res[0]).limit(old, self.point[i]) newvars[i] = var newpt[i] = point elif old not in syms: del newvars[i], newpt[i] if not syms and new == self.point[i]: newvars.extend(syms) newpt.extend([S.Zero]*len(syms)) else: return return Order(newexpr, *zip(newvars, newpt)) def _eval_conjugate(self): expr = self.expr._eval_conjugate() if expr is not None: return self.func(expr, *self.args[1:]) def _eval_derivative(self, x): return self.func(self.expr.diff(x), *self.args[1:]) or self def _eval_transpose(self): expr = self.expr._eval_transpose() if expr is not None: return self.func(expr, *self.args[1:]) def _sage_(self): #XXX: SAGE doesn't have Order yet. Let's return 0 instead. return Rational(0)._sage_() def __neg__(self): return self O = Order
7ca5746fe81331ce931bee85e213b32c567c6f84b66db77cbfc8c7ac91baff4c
from collections import defaultdict from sympy import SYMPY_DEBUG from sympy.core import expand_power_base, sympify, Add, S, Mul, Derivative, Pow, symbols, expand_mul from sympy.core.add import _unevaluated_Add from sympy.core.compatibility import iterable, ordered, default_sort_key from sympy.core.parameters import global_parameters from sympy.core.exprtools import Factors, gcd_terms from sympy.core.function import _mexpand from sympy.core.mul import _keep_coeff, _unevaluated_Mul from sympy.core.numbers import Rational from sympy.functions import exp, sqrt, log from sympy.functions.elementary.complexes import Abs from sympy.polys import gcd from sympy.simplify.sqrtdenest import sqrtdenest def collect(expr, syms, func=None, evaluate=None, exact=False, distribute_order_term=True): """ Collect additive terms of an expression. Explanation =========== This function collects additive terms of an expression with respect to a list of expression up to powers with rational exponents. By the term symbol here are meant arbitrary expressions, which can contain powers, products, sums etc. In other words symbol is a pattern which will be searched for in the expression's terms. The input expression is not expanded by :func:`collect`, so user is expected to provide an expression in an appropriate form. This makes :func:`collect` more predictable as there is no magic happening behind the scenes. However, it is important to note, that powers of products are converted to products of powers using the :func:`~.expand_power_base` function. There are two possible types of output. First, if ``evaluate`` flag is set, this function will return an expression with collected terms or else it will return a dictionary with expressions up to rational powers as keys and collected coefficients as values. Examples ======== >>> from sympy import S, collect, expand, factor, Wild >>> from sympy.abc import a, b, c, x, y This function can collect symbolic coefficients in polynomials or rational expressions. It will manage to find all integer or rational powers of collection variable:: >>> collect(a*x**2 + b*x**2 + a*x - b*x + c, x) c + x**2*(a + b) + x*(a - b) The same result can be achieved in dictionary form:: >>> d = collect(a*x**2 + b*x**2 + a*x - b*x + c, x, evaluate=False) >>> d[x**2] a + b >>> d[x] a - b >>> d[S.One] c You can also work with multivariate polynomials. However, remember that this function is greedy so it will care only about a single symbol at time, in specification order:: >>> collect(x**2 + y*x**2 + x*y + y + a*y, [x, y]) x**2*(y + 1) + x*y + y*(a + 1) Also more complicated expressions can be used as patterns:: >>> from sympy import sin, log >>> collect(a*sin(2*x) + b*sin(2*x), sin(2*x)) (a + b)*sin(2*x) >>> collect(a*x*log(x) + b*(x*log(x)), x*log(x)) x*(a + b)*log(x) You can use wildcards in the pattern:: >>> w = Wild('w1') >>> collect(a*x**y - b*x**y, w**y) x**y*(a - b) It is also possible to work with symbolic powers, although it has more complicated behavior, because in this case power's base and symbolic part of the exponent are treated as a single symbol:: >>> collect(a*x**c + b*x**c, x) a*x**c + b*x**c >>> collect(a*x**c + b*x**c, x**c) x**c*(a + b) However if you incorporate rationals to the exponents, then you will get well known behavior:: >>> collect(a*x**(2*c) + b*x**(2*c), x**c) x**(2*c)*(a + b) Note also that all previously stated facts about :func:`collect` function apply to the exponential function, so you can get:: >>> from sympy import exp >>> collect(a*exp(2*x) + b*exp(2*x), exp(x)) (a + b)*exp(2*x) If you are interested only in collecting specific powers of some symbols then set ``exact`` flag in arguments:: >>> collect(a*x**7 + b*x**7, x, exact=True) a*x**7 + b*x**7 >>> collect(a*x**7 + b*x**7, x**7, exact=True) x**7*(a + b) You can also apply this function to differential equations, where derivatives of arbitrary order can be collected. Note that if you collect with respect to a function or a derivative of a function, all derivatives of that function will also be collected. Use ``exact=True`` to prevent this from happening:: >>> from sympy import Derivative as D, collect, Function >>> f = Function('f') (x) >>> collect(a*D(f,x) + b*D(f,x), D(f,x)) (a + b)*Derivative(f(x), x) >>> collect(a*D(D(f,x),x) + b*D(D(f,x),x), f) (a + b)*Derivative(f(x), (x, 2)) >>> collect(a*D(D(f,x),x) + b*D(D(f,x),x), D(f,x), exact=True) a*Derivative(f(x), (x, 2)) + b*Derivative(f(x), (x, 2)) >>> collect(a*D(f,x) + b*D(f,x) + a*f + b*f, f) (a + b)*f(x) + (a + b)*Derivative(f(x), x) Or you can even match both derivative order and exponent at the same time:: >>> collect(a*D(D(f,x),x)**2 + b*D(D(f,x),x)**2, D(f,x)) (a + b)*Derivative(f(x), (x, 2))**2 Finally, you can apply a function to each of the collected coefficients. For example you can factorize symbolic coefficients of polynomial:: >>> f = expand((x + a + 1)**3) >>> collect(f, x, factor) x**3 + 3*x**2*(a + 1) + 3*x*(a + 1)**2 + (a + 1)**3 .. note:: Arguments are expected to be in expanded form, so you might have to call :func:`~.expand` prior to calling this function. See Also ======== collect_const, collect_sqrt, rcollect """ from sympy.core.assumptions import assumptions from sympy.utilities.iterables import sift from sympy.core.symbol import Dummy, Wild expr = sympify(expr) syms = [sympify(i) for i in (syms if iterable(syms) else [syms])] # replace syms[i] if it is not x, -x or has Wild symbols cond = lambda x: x.is_Symbol or (-x).is_Symbol or bool( x.atoms(Wild)) _, nonsyms = sift(syms, cond, binary=True) if nonsyms: reps = dict(zip(nonsyms, [Dummy(**assumptions(i)) for i in nonsyms])) syms = [reps.get(s, s) for s in syms] rv = collect(expr.subs(reps), syms, func=func, evaluate=evaluate, exact=exact, distribute_order_term=distribute_order_term) urep = {v: k for k, v in reps.items()} if not isinstance(rv, dict): return rv.xreplace(urep) else: return {urep.get(k, k).xreplace(urep): v.xreplace(urep) for k, v in rv.items()} if evaluate is None: evaluate = global_parameters.evaluate def make_expression(terms): product = [] for term, rat, sym, deriv in terms: if deriv is not None: var, order = deriv while order > 0: term, order = Derivative(term, var), order - 1 if sym is None: if rat is S.One: product.append(term) else: product.append(Pow(term, rat)) else: product.append(Pow(term, rat*sym)) return Mul(*product) def parse_derivative(deriv): # scan derivatives tower in the input expression and return # underlying function and maximal differentiation order expr, sym, order = deriv.expr, deriv.variables[0], 1 for s in deriv.variables[1:]: if s == sym: order += 1 else: raise NotImplementedError( 'Improve MV Derivative support in collect') while isinstance(expr, Derivative): s0 = expr.variables[0] for s in expr.variables: if s != s0: raise NotImplementedError( 'Improve MV Derivative support in collect') if s0 == sym: expr, order = expr.expr, order + len(expr.variables) else: break return expr, (sym, Rational(order)) def parse_term(expr): """Parses expression expr and outputs tuple (sexpr, rat_expo, sym_expo, deriv) where: - sexpr is the base expression - rat_expo is the rational exponent that sexpr is raised to - sym_expo is the symbolic exponent that sexpr is raised to - deriv contains the derivatives the the expression For example, the output of x would be (x, 1, None, None) the output of 2**x would be (2, 1, x, None). """ rat_expo, sym_expo = S.One, None sexpr, deriv = expr, None if expr.is_Pow: if isinstance(expr.base, Derivative): sexpr, deriv = parse_derivative(expr.base) else: sexpr = expr.base if expr.base == S.Exp1: arg = expr.exp if arg.is_Rational: sexpr, rat_expo = S.Exp1, arg elif arg.is_Mul: coeff, tail = arg.as_coeff_Mul(rational=True) sexpr, rat_expo = exp(tail), coeff elif expr.exp.is_Number: rat_expo = expr.exp else: coeff, tail = expr.exp.as_coeff_Mul() if coeff.is_Number: rat_expo, sym_expo = coeff, tail else: sym_expo = expr.exp elif isinstance(expr, exp): arg = expr.exp if arg.is_Rational: sexpr, rat_expo = S.Exp1, arg elif arg.is_Mul: coeff, tail = arg.as_coeff_Mul(rational=True) sexpr, rat_expo = exp(tail), coeff elif isinstance(expr, Derivative): sexpr, deriv = parse_derivative(expr) return sexpr, rat_expo, sym_expo, deriv def parse_expression(terms, pattern): """Parse terms searching for a pattern. Terms is a list of tuples as returned by parse_terms; Pattern is an expression treated as a product of factors. """ pattern = Mul.make_args(pattern) if len(terms) < len(pattern): # pattern is longer than matched product # so no chance for positive parsing result return None else: pattern = [parse_term(elem) for elem in pattern] terms = terms[:] # need a copy elems, common_expo, has_deriv = [], None, False for elem, e_rat, e_sym, e_ord in pattern: if elem.is_Number and e_rat == 1 and e_sym is None: # a constant is a match for everything continue for j in range(len(terms)): if terms[j] is None: continue term, t_rat, t_sym, t_ord = terms[j] # keeping track of whether one of the terms had # a derivative or not as this will require rebuilding # the expression later if t_ord is not None: has_deriv = True if (term.match(elem) is not None and (t_sym == e_sym or t_sym is not None and e_sym is not None and t_sym.match(e_sym) is not None)): if exact is False: # we don't have to be exact so find common exponent # for both expression's term and pattern's element expo = t_rat / e_rat if common_expo is None: # first time common_expo = expo else: # common exponent was negotiated before so # there is no chance for a pattern match unless # common and current exponents are equal if common_expo != expo: common_expo = 1 else: # we ought to be exact so all fields of # interest must match in every details if e_rat != t_rat or e_ord != t_ord: continue # found common term so remove it from the expression # and try to match next element in the pattern elems.append(terms[j]) terms[j] = None break else: # pattern element not found return None return [_f for _f in terms if _f], elems, common_expo, has_deriv if evaluate: if expr.is_Add: o = expr.getO() or 0 expr = expr.func(*[ collect(a, syms, func, True, exact, distribute_order_term) for a in expr.args if a != o]) + o elif expr.is_Mul: return expr.func(*[ collect(term, syms, func, True, exact, distribute_order_term) for term in expr.args]) elif expr.is_Pow: b = collect( expr.base, syms, func, True, exact, distribute_order_term) return Pow(b, expr.exp) syms = [expand_power_base(i, deep=False) for i in syms] order_term = None if distribute_order_term: order_term = expr.getO() if order_term is not None: if order_term.has(*syms): order_term = None else: expr = expr.removeO() summa = [expand_power_base(i, deep=False) for i in Add.make_args(expr)] collected, disliked = defaultdict(list), S.Zero for product in summa: c, nc = product.args_cnc(split_1=False) args = list(ordered(c)) + nc terms = [parse_term(i) for i in args] small_first = True for symbol in syms: if SYMPY_DEBUG: print("DEBUG: parsing of expression %s with symbol %s " % ( str(terms), str(symbol)) ) if isinstance(symbol, Derivative) and small_first: terms = list(reversed(terms)) small_first = not small_first result = parse_expression(terms, symbol) if SYMPY_DEBUG: print("DEBUG: returned %s" % str(result)) if result is not None: if not symbol.is_commutative: raise AttributeError("Can not collect noncommutative symbol") terms, elems, common_expo, has_deriv = result # when there was derivative in current pattern we # will need to rebuild its expression from scratch if not has_deriv: margs = [] for elem in elems: if elem[2] is None: e = elem[1] else: e = elem[1]*elem[2] margs.append(Pow(elem[0], e)) index = Mul(*margs) else: index = make_expression(elems) terms = expand_power_base(make_expression(terms), deep=False) index = expand_power_base(index, deep=False) collected[index].append(terms) break else: # none of the patterns matched disliked += product # add terms now for each key collected = {k: Add(*v) for k, v in collected.items()} if disliked is not S.Zero: collected[S.One] = disliked if order_term is not None: for key, val in collected.items(): collected[key] = val + order_term if func is not None: collected = { key: func(val) for key, val in collected.items()} if evaluate: return Add(*[key*val for key, val in collected.items()]) else: return collected def rcollect(expr, *vars): """ Recursively collect sums in an expression. Examples ======== >>> from sympy.simplify import rcollect >>> from sympy.abc import x, y >>> expr = (x**2*y + x*y + x + y)/(x + y) >>> rcollect(expr, y) (x + y*(x**2 + x + 1))/(x + y) See Also ======== collect, collect_const, collect_sqrt """ if expr.is_Atom or not expr.has(*vars): return expr else: expr = expr.__class__(*[rcollect(arg, *vars) for arg in expr.args]) if expr.is_Add: return collect(expr, vars) else: return expr def collect_sqrt(expr, evaluate=None): """Return expr with terms having common square roots collected together. If ``evaluate`` is False a count indicating the number of sqrt-containing terms will be returned and, if non-zero, the terms of the Add will be returned, else the expression itself will be returned as a single term. If ``evaluate`` is True, the expression with any collected terms will be returned. Note: since I = sqrt(-1), it is collected, too. Examples ======== >>> from sympy import sqrt >>> from sympy.simplify.radsimp import collect_sqrt >>> from sympy.abc import a, b >>> r2, r3, r5 = [sqrt(i) for i in [2, 3, 5]] >>> collect_sqrt(a*r2 + b*r2) sqrt(2)*(a + b) >>> collect_sqrt(a*r2 + b*r2 + a*r3 + b*r3) sqrt(2)*(a + b) + sqrt(3)*(a + b) >>> collect_sqrt(a*r2 + b*r2 + a*r3 + b*r5) sqrt(3)*a + sqrt(5)*b + sqrt(2)*(a + b) If evaluate is False then the arguments will be sorted and returned as a list and a count of the number of sqrt-containing terms will be returned: >>> collect_sqrt(a*r2 + b*r2 + a*r3 + b*r5, evaluate=False) ((sqrt(3)*a, sqrt(5)*b, sqrt(2)*(a + b)), 3) >>> collect_sqrt(a*sqrt(2) + b, evaluate=False) ((b, sqrt(2)*a), 1) >>> collect_sqrt(a + b, evaluate=False) ((a + b,), 0) See Also ======== collect, collect_const, rcollect """ if evaluate is None: evaluate = global_parameters.evaluate # this step will help to standardize any complex arguments # of sqrts coeff, expr = expr.as_content_primitive() vars = set() for a in Add.make_args(expr): for m in a.args_cnc()[0]: if m.is_number and ( m.is_Pow and m.exp.is_Rational and m.exp.q == 2 or m is S.ImaginaryUnit): vars.add(m) # we only want radicals, so exclude Number handling; in this case # d will be evaluated d = collect_const(expr, *vars, Numbers=False) hit = expr != d if not evaluate: nrad = 0 # make the evaluated args canonical args = list(ordered(Add.make_args(d))) for i, m in enumerate(args): c, nc = m.args_cnc() for ci in c: # XXX should this be restricted to ci.is_number as above? if ci.is_Pow and ci.exp.is_Rational and ci.exp.q == 2 or \ ci is S.ImaginaryUnit: nrad += 1 break args[i] *= coeff if not (hit or nrad): args = [Add(*args)] return tuple(args), nrad return coeff*d def collect_abs(expr): """Return ``expr`` with arguments of multiple Abs in a term collected under a single instance. Examples ======== >>> from sympy.simplify.radsimp import collect_abs >>> from sympy.abc import x >>> collect_abs(abs(x + 1)/abs(x**2 - 1)) Abs((x + 1)/(x**2 - 1)) >>> collect_abs(abs(1/x)) Abs(1/x) """ def _abs(mul): from sympy.core.mul import _mulsort c, nc = mul.args_cnc() a = [] o = [] for i in c: if isinstance(i, Abs): a.append(i.args[0]) elif isinstance(i, Pow) and isinstance(i.base, Abs) and i.exp.is_real: a.append(i.base.args[0]**i.exp) else: o.append(i) if len(a) < 2 and not any(i.exp.is_negative for i in a if isinstance(i, Pow)): return mul absarg = Mul(*a) A = Abs(absarg) args = [A] args.extend(o) if not A.has(Abs): args.extend(nc) return Mul(*args) if not isinstance(A, Abs): # reevaluate and make it unevaluated A = Abs(absarg, evaluate=False) args[0] = A _mulsort(args) args.extend(nc) # nc always go last return Mul._from_args(args, is_commutative=not nc) return expr.replace( lambda x: isinstance(x, Mul), lambda x: _abs(x)).replace( lambda x: isinstance(x, Pow), lambda x: _abs(x)) def collect_const(expr, *vars, Numbers=True): """A non-greedy collection of terms with similar number coefficients in an Add expr. If ``vars`` is given then only those constants will be targeted. Although any Number can also be targeted, if this is not desired set ``Numbers=False`` and no Float or Rational will be collected. Parameters ========== expr : sympy expression This parameter defines the expression the expression from which terms with similar coefficients are to be collected. A non-Add expression is returned as it is. vars : variable length collection of Numbers, optional Specifies the constants to target for collection. Can be multiple in number. Numbers : bool Specifies to target all instance of :class:`sympy.core.numbers.Number` class. If ``Numbers=False``, then no Float or Rational will be collected. Returns ======= expr : Expr Returns an expression with similar coefficient terms collected. Examples ======== >>> from sympy import sqrt >>> from sympy.abc import s, x, y, z >>> from sympy.simplify.radsimp import collect_const >>> collect_const(sqrt(3) + sqrt(3)*(1 + sqrt(2))) sqrt(3)*(sqrt(2) + 2) >>> collect_const(sqrt(3)*s + sqrt(7)*s + sqrt(3) + sqrt(7)) (sqrt(3) + sqrt(7))*(s + 1) >>> s = sqrt(2) + 2 >>> collect_const(sqrt(3)*s + sqrt(3) + sqrt(7)*s + sqrt(7)) (sqrt(2) + 3)*(sqrt(3) + sqrt(7)) >>> collect_const(sqrt(3)*s + sqrt(3) + sqrt(7)*s + sqrt(7), sqrt(3)) sqrt(7) + sqrt(3)*(sqrt(2) + 3) + sqrt(7)*(sqrt(2) + 2) The collection is sign-sensitive, giving higher precedence to the unsigned values: >>> collect_const(x - y - z) x - (y + z) >>> collect_const(-y - z) -(y + z) >>> collect_const(2*x - 2*y - 2*z, 2) 2*(x - y - z) >>> collect_const(2*x - 2*y - 2*z, -2) 2*x - 2*(y + z) See Also ======== collect, collect_sqrt, rcollect """ if not expr.is_Add: return expr recurse = False if not vars: recurse = True vars = set() for a in expr.args: for m in Mul.make_args(a): if m.is_number: vars.add(m) else: vars = sympify(vars) if not Numbers: vars = [v for v in vars if not v.is_Number] vars = list(ordered(vars)) for v in vars: terms = defaultdict(list) Fv = Factors(v) for m in Add.make_args(expr): f = Factors(m) q, r = f.div(Fv) if r.is_one: # only accept this as a true factor if # it didn't change an exponent from an Integer # to a non-Integer, e.g. 2/sqrt(2) -> sqrt(2) # -- we aren't looking for this sort of change fwas = f.factors.copy() fnow = q.factors if not any(k in fwas and fwas[k].is_Integer and not fnow[k].is_Integer for k in fnow): terms[v].append(q.as_expr()) continue terms[S.One].append(m) args = [] hit = False uneval = False for k in ordered(terms): v = terms[k] if k is S.One: args.extend(v) continue if len(v) > 1: v = Add(*v) hit = True if recurse and v != expr: vars.append(v) else: v = v[0] # be careful not to let uneval become True unless # it must be because it's going to be more expensive # to rebuild the expression as an unevaluated one if Numbers and k.is_Number and v.is_Add: args.append(_keep_coeff(k, v, sign=True)) uneval = True else: args.append(k*v) if hit: if uneval: expr = _unevaluated_Add(*args) else: expr = Add(*args) if not expr.is_Add: break return expr def radsimp(expr, symbolic=True, max_terms=4): r""" Rationalize the denominator by removing square roots. Explanation =========== The expression returned from radsimp must be used with caution since if the denominator contains symbols, it will be possible to make substitutions that violate the assumptions of the simplification process: that for a denominator matching a + b*sqrt(c), a != +/-b*sqrt(c). (If there are no symbols, this assumptions is made valid by collecting terms of sqrt(c) so the match variable ``a`` does not contain ``sqrt(c)``.) If you do not want the simplification to occur for symbolic denominators, set ``symbolic`` to False. If there are more than ``max_terms`` radical terms then the expression is returned unchanged. Examples ======== >>> from sympy import radsimp, sqrt, Symbol, pprint >>> from sympy import factor_terms, fraction, signsimp >>> from sympy.simplify.radsimp import collect_sqrt >>> from sympy.abc import a, b, c >>> radsimp(1/(2 + sqrt(2))) (2 - sqrt(2))/2 >>> x,y = map(Symbol, 'xy') >>> e = ((2 + 2*sqrt(2))*x + (2 + sqrt(8))*y)/(2 + sqrt(2)) >>> radsimp(e) sqrt(2)*(x + y) No simplification beyond removal of the gcd is done. One might want to polish the result a little, however, by collecting square root terms: >>> r2 = sqrt(2) >>> r5 = sqrt(5) >>> ans = radsimp(1/(y*r2 + x*r2 + a*r5 + b*r5)); pprint(ans) ___ ___ ___ ___ \/ 5 *a + \/ 5 *b - \/ 2 *x - \/ 2 *y ------------------------------------------ 2 2 2 2 5*a + 10*a*b + 5*b - 2*x - 4*x*y - 2*y >>> n, d = fraction(ans) >>> pprint(factor_terms(signsimp(collect_sqrt(n))/d, radical=True)) ___ ___ \/ 5 *(a + b) - \/ 2 *(x + y) ------------------------------------------ 2 2 2 2 5*a + 10*a*b + 5*b - 2*x - 4*x*y - 2*y If radicals in the denominator cannot be removed or there is no denominator, the original expression will be returned. >>> radsimp(sqrt(2)*x + sqrt(2)) sqrt(2)*x + sqrt(2) Results with symbols will not always be valid for all substitutions: >>> eq = 1/(a + b*sqrt(c)) >>> eq.subs(a, b*sqrt(c)) 1/(2*b*sqrt(c)) >>> radsimp(eq).subs(a, b*sqrt(c)) nan If ``symbolic=False``, symbolic denominators will not be transformed (but numeric denominators will still be processed): >>> radsimp(eq, symbolic=False) 1/(a + b*sqrt(c)) """ from sympy.simplify.simplify import signsimp syms = symbols("a:d A:D") def _num(rterms): # return the multiplier that will simplify the expression described # by rterms [(sqrt arg, coeff), ... ] a, b, c, d, A, B, C, D = syms if len(rterms) == 2: reps = dict(list(zip([A, a, B, b], [j for i in rterms for j in i]))) return ( sqrt(A)*a - sqrt(B)*b).xreplace(reps) if len(rterms) == 3: reps = dict(list(zip([A, a, B, b, C, c], [j for i in rterms for j in i]))) return ( (sqrt(A)*a + sqrt(B)*b - sqrt(C)*c)*(2*sqrt(A)*sqrt(B)*a*b - A*a**2 - B*b**2 + C*c**2)).xreplace(reps) elif len(rterms) == 4: reps = dict(list(zip([A, a, B, b, C, c, D, d], [j for i in rterms for j in i]))) return ((sqrt(A)*a + sqrt(B)*b - sqrt(C)*c - sqrt(D)*d)*(2*sqrt(A)*sqrt(B)*a*b - A*a**2 - B*b**2 - 2*sqrt(C)*sqrt(D)*c*d + C*c**2 + D*d**2)*(-8*sqrt(A)*sqrt(B)*sqrt(C)*sqrt(D)*a*b*c*d + A**2*a**4 - 2*A*B*a**2*b**2 - 2*A*C*a**2*c**2 - 2*A*D*a**2*d**2 + B**2*b**4 - 2*B*C*b**2*c**2 - 2*B*D*b**2*d**2 + C**2*c**4 - 2*C*D*c**2*d**2 + D**2*d**4)).xreplace(reps) elif len(rterms) == 1: return sqrt(rterms[0][0]) else: raise NotImplementedError def ispow2(d, log2=False): if not d.is_Pow: return False e = d.exp if e.is_Rational and e.q == 2 or symbolic and denom(e) == 2: return True if log2: q = 1 if e.is_Rational: q = e.q elif symbolic: d = denom(e) if d.is_Integer: q = d if q != 1 and log(q, 2).is_Integer: return True return False def handle(expr): # Handle first reduces to the case # expr = 1/d, where d is an add, or d is base**p/2. # We do this by recursively calling handle on each piece. from sympy.simplify.simplify import nsimplify n, d = fraction(expr) if expr.is_Atom or (d.is_Atom and n.is_Atom): return expr elif not n.is_Atom: n = n.func(*[handle(a) for a in n.args]) return _unevaluated_Mul(n, handle(1/d)) elif n is not S.One: return _unevaluated_Mul(n, handle(1/d)) elif d.is_Mul: return _unevaluated_Mul(*[handle(1/d) for d in d.args]) # By this step, expr is 1/d, and d is not a mul. if not symbolic and d.free_symbols: return expr if ispow2(d): d2 = sqrtdenest(sqrt(d.base))**numer(d.exp) if d2 != d: return handle(1/d2) elif d.is_Pow and (d.exp.is_integer or d.base.is_positive): # (1/d**i) = (1/d)**i return handle(1/d.base)**d.exp if not (d.is_Add or ispow2(d)): return 1/d.func(*[handle(a) for a in d.args]) # handle 1/d treating d as an Add (though it may not be) keep = True # keep changes that are made # flatten it and collect radicals after checking for special # conditions d = _mexpand(d) # did it change? if d.is_Atom: return 1/d # is it a number that might be handled easily? if d.is_number: _d = nsimplify(d) if _d.is_Number and _d.equals(d): return 1/_d while True: # collect similar terms collected = defaultdict(list) for m in Add.make_args(d): # d might have become non-Add p2 = [] other = [] for i in Mul.make_args(m): if ispow2(i, log2=True): p2.append(i.base if i.exp is S.Half else i.base**(2*i.exp)) elif i is S.ImaginaryUnit: p2.append(S.NegativeOne) else: other.append(i) collected[tuple(ordered(p2))].append(Mul(*other)) rterms = list(ordered(list(collected.items()))) rterms = [(Mul(*i), Add(*j)) for i, j in rterms] nrad = len(rterms) - (1 if rterms[0][0] is S.One else 0) if nrad < 1: break elif nrad > max_terms: # there may have been invalid operations leading to this point # so don't keep changes, e.g. this expression is troublesome # in collecting terms so as not to raise the issue of 2834: # r = sqrt(sqrt(5) + 5) # eq = 1/(sqrt(5)*r + 2*sqrt(5)*sqrt(-sqrt(5) + 5) + 5*r) keep = False break if len(rterms) > 4: # in general, only 4 terms can be removed with repeated squaring # but other considerations can guide selection of radical terms # so that radicals are removed if all([x.is_Integer and (y**2).is_Rational for x, y in rterms]): nd, d = rad_rationalize(S.One, Add._from_args( [sqrt(x)*y for x, y in rterms])) n *= nd else: # is there anything else that might be attempted? keep = False break from sympy.simplify.powsimp import powsimp, powdenest num = powsimp(_num(rterms)) n *= num d *= num d = powdenest(_mexpand(d), force=symbolic) if d.is_Atom: break if not keep: return expr return _unevaluated_Mul(n, 1/d) coeff, expr = expr.as_coeff_Add() expr = expr.normal() old = fraction(expr) n, d = fraction(handle(expr)) if old != (n, d): if not d.is_Atom: was = (n, d) n = signsimp(n, evaluate=False) d = signsimp(d, evaluate=False) u = Factors(_unevaluated_Mul(n, 1/d)) u = _unevaluated_Mul(*[k**v for k, v in u.factors.items()]) n, d = fraction(u) if old == (n, d): n, d = was n = expand_mul(n) if d.is_Number or d.is_Add: n2, d2 = fraction(gcd_terms(_unevaluated_Mul(n, 1/d))) if d2.is_Number or (d2.count_ops() <= d.count_ops()): n, d = [signsimp(i) for i in (n2, d2)] if n.is_Mul and n.args[0].is_Number: n = n.func(*n.args) return coeff + _unevaluated_Mul(n, 1/d) def rad_rationalize(num, den): """ Rationalize ``num/den`` by removing square roots in the denominator; num and den are sum of terms whose squares are positive rationals. Examples ======== >>> from sympy import sqrt >>> from sympy.simplify.radsimp import rad_rationalize >>> rad_rationalize(sqrt(3), 1 + sqrt(2)/3) (-sqrt(3) + sqrt(6)/3, -7/9) """ if not den.is_Add: return num, den g, a, b = split_surds(den) a = a*sqrt(g) num = _mexpand((a - b)*num) den = _mexpand(a**2 - b**2) return rad_rationalize(num, den) def fraction(expr, exact=False): """Returns a pair with expression's numerator and denominator. If the given expression is not a fraction then this function will return the tuple (expr, 1). This function will not make any attempt to simplify nested fractions or to do any term rewriting at all. If only one of the numerator/denominator pair is needed then use numer(expr) or denom(expr) functions respectively. >>> from sympy import fraction, Rational, Symbol >>> from sympy.abc import x, y >>> fraction(x/y) (x, y) >>> fraction(x) (x, 1) >>> fraction(1/y**2) (1, y**2) >>> fraction(x*y/2) (x*y, 2) >>> fraction(Rational(1, 2)) (1, 2) This function will also work fine with assumptions: >>> k = Symbol('k', negative=True) >>> fraction(x * y**k) (x, y**(-k)) If we know nothing about sign of some exponent and ``exact`` flag is unset, then structure this exponent's structure will be analyzed and pretty fraction will be returned: >>> from sympy import exp, Mul >>> fraction(2*x**(-y)) (2, x**y) >>> fraction(exp(-x)) (1, exp(x)) >>> fraction(exp(-x), exact=True) (exp(-x), 1) The ``exact`` flag will also keep any unevaluated Muls from being evaluated: >>> u = Mul(2, x + 1, evaluate=False) >>> fraction(u) (2*x + 2, 1) >>> fraction(u, exact=True) (2*(x + 1), 1) """ expr = sympify(expr) numer, denom = [], [] for term in Mul.make_args(expr): if term.is_commutative and (term.is_Pow or isinstance(term, exp)): b, ex = term.as_base_exp() if ex.is_negative: if ex is S.NegativeOne: denom.append(b) elif exact: if ex.is_constant(): denom.append(Pow(b, -ex)) else: numer.append(term) else: denom.append(Pow(b, -ex)) elif ex.is_positive: numer.append(term) elif not exact and ex.is_Mul: n, d = term.as_numer_denom() if n != 1: numer.append(n) denom.append(d) else: numer.append(term) elif term.is_Rational and not term.is_Integer: if term.p != 1: numer.append(term.p) denom.append(term.q) else: numer.append(term) return Mul(*numer, evaluate=not exact), Mul(*denom, evaluate=not exact) def numer(expr): return fraction(expr)[0] def denom(expr): return fraction(expr)[1] def fraction_expand(expr, **hints): return expr.expand(frac=True, **hints) def numer_expand(expr, **hints): a, b = fraction(expr) return a.expand(numer=True, **hints) / b def denom_expand(expr, **hints): a, b = fraction(expr) return a / b.expand(denom=True, **hints) expand_numer = numer_expand expand_denom = denom_expand expand_fraction = fraction_expand def split_surds(expr): """ Split an expression with terms whose squares are positive rationals into a sum of terms whose surds squared have gcd equal to g and a sum of terms with surds squared prime with g. Examples ======== >>> from sympy import sqrt >>> from sympy.simplify.radsimp import split_surds >>> split_surds(3*sqrt(3) + sqrt(5)/7 + sqrt(6) + sqrt(10) + sqrt(15)) (3, sqrt(2) + sqrt(5) + 3, sqrt(5)/7 + sqrt(10)) """ args = sorted(expr.args, key=default_sort_key) coeff_muls = [x.as_coeff_Mul() for x in args] surds = [x[1]**2 for x in coeff_muls if x[1].is_Pow] surds.sort(key=default_sort_key) g, b1, b2 = _split_gcd(*surds) g2 = g if not b2 and len(b1) >= 2: b1n = [x/g for x in b1] b1n = [x for x in b1n if x != 1] # only a common factor has been factored; split again g1, b1n, b2 = _split_gcd(*b1n) g2 = g*g1 a1v, a2v = [], [] for c, s in coeff_muls: if s.is_Pow and s.exp == S.Half: s1 = s.base if s1 in b1: a1v.append(c*sqrt(s1/g2)) else: a2v.append(c*s) else: a2v.append(c*s) a = Add(*a1v) b = Add(*a2v) return g2, a, b def _split_gcd(*a): """ Split the list of integers ``a`` into a list of integers, ``a1`` having ``g = gcd(a1)``, and a list ``a2`` whose elements are not divisible by ``g``. Returns ``g, a1, a2``. Examples ======== >>> from sympy.simplify.radsimp import _split_gcd >>> _split_gcd(55, 35, 22, 14, 77, 10) (5, [55, 35, 10], [22, 14, 77]) """ g = a[0] b1 = [g] b2 = [] for x in a[1:]: g1 = gcd(g, x) if g1 == 1: b2.append(x) else: g = g1 b1.append(x) return g, b1, b2
2aa6066e14974355491397b0c9a0f42657e04ea3376e470b4f26033779974763
""" Tools for doing common subexpression elimination. """ from sympy.core import Basic, Mul, Add, Pow, sympify, Symbol from sympy.core.compatibility import iterable from sympy.core.containers import Tuple, OrderedSet from sympy.core.exprtools import factor_terms from sympy.core.function import _coeff_isneg from sympy.core.singleton import S from sympy.utilities.iterables import numbered_symbols, sift, \ topological_sort, ordered from . import cse_opts # (preprocessor, postprocessor) pairs which are commonly useful. They should # each take a sympy expression and return a possibly transformed expression. # When used in the function ``cse()``, the target expressions will be transformed # by each of the preprocessor functions in order. After the common # subexpressions are eliminated, each resulting expression will have the # postprocessor functions transform them in *reverse* order in order to undo the # transformation if necessary. This allows the algorithm to operate on # a representation of the expressions that allows for more optimization # opportunities. # ``None`` can be used to specify no transformation for either the preprocessor or # postprocessor. basic_optimizations = [(cse_opts.sub_pre, cse_opts.sub_post), (factor_terms, None)] # sometimes we want the output in a different format; non-trivial # transformations can be put here for users # =============================================================== def reps_toposort(r): """Sort replacements ``r`` so (k1, v1) appears before (k2, v2) if k2 is in v1's free symbols. This orders items in the way that cse returns its results (hence, in order to use the replacements in a substitution option it would make sense to reverse the order). Examples ======== >>> from sympy.simplify.cse_main import reps_toposort >>> from sympy.abc import x, y >>> from sympy import Eq >>> for l, r in reps_toposort([(x, y + 1), (y, 2)]): ... print(Eq(l, r)) ... Eq(y, 2) Eq(x, y + 1) """ r = sympify(r) E = [] for c1, (k1, v1) in enumerate(r): for c2, (k2, v2) in enumerate(r): if k1 in v2.free_symbols: E.append((c1, c2)) return [r[i] for i in topological_sort((range(len(r)), E))] def cse_separate(r, e): """Move expressions that are in the form (symbol, expr) out of the expressions and sort them into the replacements using the reps_toposort. Examples ======== >>> from sympy.simplify.cse_main import cse_separate >>> from sympy.abc import x, y, z >>> from sympy import cos, exp, cse, Eq, symbols >>> x0, x1 = symbols('x:2') >>> eq = (x + 1 + exp((x + 1)/(y + 1)) + cos(y + 1)) >>> cse([eq, Eq(x, z + 1), z - 2], postprocess=cse_separate) in [ ... [[(x0, y + 1), (x, z + 1), (x1, x + 1)], ... [x1 + exp(x1/x0) + cos(x0), z - 2]], ... [[(x1, y + 1), (x, z + 1), (x0, x + 1)], ... [x0 + exp(x0/x1) + cos(x1), z - 2]]] ... True """ d = sift(e, lambda w: w.is_Equality and w.lhs.is_Symbol) r = r + [w.args for w in d[True]] e = d[False] return [reps_toposort(r), e] def cse_release_variables(r, e): """ Return tuples giving ``(a, b)`` where ``a`` is a symbol and ``b`` is either an expression or None. The value of None is used when a symbol is no longer needed for subsequent expressions. Use of such output can reduce the memory footprint of lambdified expressions that contain large, repeated subexpressions. Examples ======== >>> from sympy import cse >>> from sympy.simplify.cse_main import cse_release_variables >>> from sympy.abc import x, y >>> eqs = [(x + y - 1)**2, x, x + y, (x + y)/(2*x + 1) + (x + y - 1)**2, (2*x + 1)**(x + y)] >>> defs, rvs = cse_release_variables(*cse(eqs)) >>> for i in defs: ... print(i) ... (x0, x + y) (x1, (x0 - 1)**2) (x2, 2*x + 1) (_3, x0/x2 + x1) (_4, x2**x0) (x2, None) (_0, x1) (x1, None) (_2, x0) (x0, None) (_1, x) >>> print(rvs) (_0, _1, _2, _3, _4) """ if not r: return r, e from sympy import symbols s, p = zip(*r) esyms = symbols('_:%d' % len(e)) syms = list(esyms) s = list(s) in_use = set(s) p = list(p) # sort e so those with most sub-expressions appear first e = [(e[i], syms[i]) for i in range(len(e))] e, syms = zip(*sorted(e, key=lambda x: -sum([p[s.index(i)].count_ops() for i in x[0].free_symbols & in_use]))) syms = list(syms) p += e rv = [] i = len(p) - 1 while i >= 0: _p = p.pop() c = in_use & _p.free_symbols if c: # sorting for canonical results rv.extend([(s, None) for s in sorted(c, key=str)]) if i >= len(r): rv.append((syms.pop(), _p)) else: rv.append((s[i], _p)) in_use -= c i -= 1 rv.reverse() return rv, esyms # ====end of cse postprocess idioms=========================== def preprocess_for_cse(expr, optimizations): """ Preprocess an expression to optimize for common subexpression elimination. Parameters ========== expr : sympy expression The target expression to optimize. optimizations : list of (callable, callable) pairs The (preprocessor, postprocessor) pairs. Returns ======= expr : sympy expression The transformed expression. """ for pre, post in optimizations: if pre is not None: expr = pre(expr) return expr def postprocess_for_cse(expr, optimizations): """Postprocess an expression after common subexpression elimination to return the expression to canonical SymPy form. Parameters ========== expr : sympy expression The target expression to transform. optimizations : list of (callable, callable) pairs, optional The (preprocessor, postprocessor) pairs. The postprocessors will be applied in reversed order to undo the effects of the preprocessors correctly. Returns ======= expr : sympy expression The transformed expression. """ for pre, post in reversed(optimizations): if post is not None: expr = post(expr) return expr class FuncArgTracker: """ A class which manages a mapping from functions to arguments and an inverse mapping from arguments to functions. """ def __init__(self, funcs): # To minimize the number of symbolic comparisons, all function arguments # get assigned a value number. self.value_numbers = {} self.value_number_to_value = [] # Both of these maps use integer indices for arguments / functions. self.arg_to_funcset = [] self.func_to_argset = [] for func_i, func in enumerate(funcs): func_argset = OrderedSet() for func_arg in func.args: arg_number = self.get_or_add_value_number(func_arg) func_argset.add(arg_number) self.arg_to_funcset[arg_number].add(func_i) self.func_to_argset.append(func_argset) def get_args_in_value_order(self, argset): """ Return the list of arguments in sorted order according to their value numbers. """ return [self.value_number_to_value[argn] for argn in sorted(argset)] def get_or_add_value_number(self, value): """ Return the value number for the given argument. """ nvalues = len(self.value_numbers) value_number = self.value_numbers.setdefault(value, nvalues) if value_number == nvalues: self.value_number_to_value.append(value) self.arg_to_funcset.append(OrderedSet()) return value_number def stop_arg_tracking(self, func_i): """ Remove the function func_i from the argument to function mapping. """ for arg in self.func_to_argset[func_i]: self.arg_to_funcset[arg].remove(func_i) def get_common_arg_candidates(self, argset, min_func_i=0): """Return a dict whose keys are function numbers. The entries of the dict are the number of arguments said function has in common with ``argset``. Entries have at least 2 items in common. All keys have value at least ``min_func_i``. """ from collections import defaultdict count_map = defaultdict(lambda: 0) if not argset: return count_map funcsets = [self.arg_to_funcset[arg] for arg in argset] # As an optimization below, we handle the largest funcset separately from # the others. largest_funcset = max(funcsets, key=len) for funcset in funcsets: if largest_funcset is funcset: continue for func_i in funcset: if func_i >= min_func_i: count_map[func_i] += 1 # We pick the smaller of the two containers (count_map, largest_funcset) # to iterate over to reduce the number of iterations needed. (smaller_funcs_container, larger_funcs_container) = sorted( [largest_funcset, count_map], key=len) for func_i in smaller_funcs_container: # Not already in count_map? It can't possibly be in the output, so # skip it. if count_map[func_i] < 1: continue if func_i in larger_funcs_container: count_map[func_i] += 1 return {k: v for k, v in count_map.items() if v >= 2} def get_subset_candidates(self, argset, restrict_to_funcset=None): """ Return a set of functions each of which whose argument list contains ``argset``, optionally filtered only to contain functions in ``restrict_to_funcset``. """ iarg = iter(argset) indices = OrderedSet( fi for fi in self.arg_to_funcset[next(iarg)]) if restrict_to_funcset is not None: indices &= restrict_to_funcset for arg in iarg: indices &= self.arg_to_funcset[arg] return indices def update_func_argset(self, func_i, new_argset): """ Update a function with a new set of arguments. """ new_args = OrderedSet(new_argset) old_args = self.func_to_argset[func_i] for deleted_arg in old_args - new_args: self.arg_to_funcset[deleted_arg].remove(func_i) for added_arg in new_args - old_args: self.arg_to_funcset[added_arg].add(func_i) self.func_to_argset[func_i].clear() self.func_to_argset[func_i].update(new_args) class Unevaluated: def __init__(self, func, args): self.func = func self.args = args def __str__(self): return "Uneval<{}>({})".format( self.func, ", ".join(str(a) for a in self.args)) def as_unevaluated_basic(self): return self.func(*self.args, evaluate=False) @property def free_symbols(self): return set().union(*[a.free_symbols for a in self.args]) __repr__ = __str__ def match_common_args(func_class, funcs, opt_subs): """ Recognize and extract common subexpressions of function arguments within a set of function calls. For instance, for the following function calls:: x + z + y sin(x + y) this will extract a common subexpression of `x + y`:: w = x + y w + z sin(w) The function we work with is assumed to be associative and commutative. Parameters ========== func_class: class The function class (e.g. Add, Mul) funcs: list of functions A list of function calls. opt_subs: dict A dictionary of substitutions which this function may update. """ # Sort to ensure that whole-function subexpressions come before the items # that use them. funcs = sorted(funcs, key=lambda f: len(f.args)) arg_tracker = FuncArgTracker(funcs) changed = OrderedSet() for i in range(len(funcs)): common_arg_candidates_counts = arg_tracker.get_common_arg_candidates( arg_tracker.func_to_argset[i], min_func_i=i + 1) # Sort the candidates in order of match size. # This makes us try combining smaller matches first. common_arg_candidates = OrderedSet(sorted( common_arg_candidates_counts.keys(), key=lambda k: (common_arg_candidates_counts[k], k))) while common_arg_candidates: j = common_arg_candidates.pop(last=False) com_args = arg_tracker.func_to_argset[i].intersection( arg_tracker.func_to_argset[j]) if len(com_args) <= 1: # This may happen if a set of common arguments was already # combined in a previous iteration. continue # For all sets, replace the common symbols by the function # over them, to allow recursive matches. diff_i = arg_tracker.func_to_argset[i].difference(com_args) if diff_i: # com_func needs to be unevaluated to allow for recursive matches. com_func = Unevaluated( func_class, arg_tracker.get_args_in_value_order(com_args)) com_func_number = arg_tracker.get_or_add_value_number(com_func) arg_tracker.update_func_argset(i, diff_i | OrderedSet([com_func_number])) changed.add(i) else: # Treat the whole expression as a CSE. # # The reason this needs to be done is somewhat subtle. Within # tree_cse(), to_eliminate only contains expressions that are # seen more than once. The problem is unevaluated expressions # do not compare equal to the evaluated equivalent. So # tree_cse() won't mark funcs[i] as a CSE if we use an # unevaluated version. com_func_number = arg_tracker.get_or_add_value_number(funcs[i]) diff_j = arg_tracker.func_to_argset[j].difference(com_args) arg_tracker.update_func_argset(j, diff_j | OrderedSet([com_func_number])) changed.add(j) for k in arg_tracker.get_subset_candidates( com_args, common_arg_candidates): diff_k = arg_tracker.func_to_argset[k].difference(com_args) arg_tracker.update_func_argset(k, diff_k | OrderedSet([com_func_number])) changed.add(k) if i in changed: opt_subs[funcs[i]] = Unevaluated(func_class, arg_tracker.get_args_in_value_order(arg_tracker.func_to_argset[i])) arg_tracker.stop_arg_tracking(i) def opt_cse(exprs, order='canonical'): """Find optimization opportunities in Adds, Muls, Pows and negative coefficient Muls. Parameters ========== exprs : list of sympy expressions The expressions to optimize. order : string, 'none' or 'canonical' The order by which Mul and Add arguments are processed. For large expressions where speed is a concern, use the setting order='none'. Returns ======= opt_subs : dictionary of expression substitutions The expression substitutions which can be useful to optimize CSE. Examples ======== >>> from sympy.simplify.cse_main import opt_cse >>> from sympy.abc import x >>> opt_subs = opt_cse([x**-2]) >>> k, v = list(opt_subs.keys())[0], list(opt_subs.values())[0] >>> print((k, v.as_unevaluated_basic())) (x**(-2), 1/(x**2)) """ from sympy.matrices.expressions import MatAdd, MatMul, MatPow opt_subs = dict() adds = OrderedSet() muls = OrderedSet() seen_subexp = set() def _find_opts(expr): if not isinstance(expr, (Basic, Unevaluated)): return if expr.is_Atom or expr.is_Order: return if iterable(expr): list(map(_find_opts, expr)) return if expr in seen_subexp: return expr seen_subexp.add(expr) list(map(_find_opts, expr.args)) if _coeff_isneg(expr): neg_expr = -expr if not neg_expr.is_Atom: opt_subs[expr] = Unevaluated(Mul, (S.NegativeOne, neg_expr)) seen_subexp.add(neg_expr) expr = neg_expr if isinstance(expr, (Mul, MatMul)): muls.add(expr) elif isinstance(expr, (Add, MatAdd)): adds.add(expr) elif isinstance(expr, (Pow, MatPow)): base, exp = expr.base, expr.exp if _coeff_isneg(exp): opt_subs[expr] = Unevaluated(Pow, (Pow(base, -exp), -1)) for e in exprs: if isinstance(e, (Basic, Unevaluated)): _find_opts(e) # split muls into commutative commutative_muls = OrderedSet() for m in muls: c, nc = m.args_cnc(cset=False) if c: c_mul = m.func(*c) if nc: if c_mul == 1: new_obj = m.func(*nc) else: new_obj = m.func(c_mul, m.func(*nc), evaluate=False) opt_subs[m] = new_obj if len(c) > 1: commutative_muls.add(c_mul) match_common_args(Add, adds, opt_subs) match_common_args(Mul, commutative_muls, opt_subs) return opt_subs def tree_cse(exprs, symbols, opt_subs=None, order='canonical', ignore=()): """Perform raw CSE on expression tree, taking opt_subs into account. Parameters ========== exprs : list of sympy expressions The expressions to reduce. symbols : infinite iterator yielding unique Symbols The symbols used to label the common subexpressions which are pulled out. opt_subs : dictionary of expression substitutions The expressions to be substituted before any CSE action is performed. order : string, 'none' or 'canonical' The order by which Mul and Add arguments are processed. For large expressions where speed is a concern, use the setting order='none'. ignore : iterable of Symbols Substitutions containing any Symbol from ``ignore`` will be ignored. """ from sympy.matrices.expressions import MatrixExpr, MatrixSymbol, MatMul, MatAdd from sympy.polys.rootoftools import RootOf if opt_subs is None: opt_subs = dict() ## Find repeated sub-expressions to_eliminate = set() seen_subexp = set() excluded_symbols = set() def _find_repeated(expr): if not isinstance(expr, (Basic, Unevaluated)): return if isinstance(expr, RootOf): return if isinstance(expr, Basic) and (expr.is_Atom or expr.is_Order): if expr.is_Symbol: excluded_symbols.add(expr) return if iterable(expr): args = expr else: if expr in seen_subexp: for ign in ignore: if ign in expr.free_symbols: break else: to_eliminate.add(expr) return seen_subexp.add(expr) if expr in opt_subs: expr = opt_subs[expr] args = expr.args list(map(_find_repeated, args)) for e in exprs: if isinstance(e, Basic): _find_repeated(e) ## Rebuild tree # Remove symbols from the generator that conflict with names in the expressions. symbols = (symbol for symbol in symbols if symbol not in excluded_symbols) replacements = [] subs = dict() def _rebuild(expr): if not isinstance(expr, (Basic, Unevaluated)): return expr if not expr.args: return expr if iterable(expr): new_args = [_rebuild(arg) for arg in expr] return expr.func(*new_args) if expr in subs: return subs[expr] orig_expr = expr if expr in opt_subs: expr = opt_subs[expr] # If enabled, parse Muls and Adds arguments by order to ensure # replacement order independent from hashes if order != 'none': if isinstance(expr, (Mul, MatMul)): c, nc = expr.args_cnc() if c == [1]: args = nc else: args = list(ordered(c)) + nc elif isinstance(expr, (Add, MatAdd)): args = list(ordered(expr.args)) else: args = expr.args else: args = expr.args new_args = list(map(_rebuild, args)) if isinstance(expr, Unevaluated) or new_args != args: new_expr = expr.func(*new_args) else: new_expr = expr if orig_expr in to_eliminate: try: sym = next(symbols) except StopIteration: raise ValueError("Symbols iterator ran out of symbols.") if isinstance(orig_expr, MatrixExpr): sym = MatrixSymbol(sym.name, orig_expr.rows, orig_expr.cols) subs[orig_expr] = sym replacements.append((sym, new_expr)) return sym else: return new_expr reduced_exprs = [] for e in exprs: if isinstance(e, Basic): reduced_e = _rebuild(e) else: reduced_e = e reduced_exprs.append(reduced_e) return replacements, reduced_exprs def cse(exprs, symbols=None, optimizations=None, postprocess=None, order='canonical', ignore=(), list=True): """ Perform common subexpression elimination on an expression. Parameters ========== exprs : list of sympy expressions, or a single sympy expression The expressions to reduce. symbols : infinite iterator yielding unique Symbols The symbols used to label the common subexpressions which are pulled out. The ``numbered_symbols`` generator is useful. The default is a stream of symbols of the form "x0", "x1", etc. This must be an infinite iterator. optimizations : list of (callable, callable) pairs The (preprocessor, postprocessor) pairs of external optimization functions. Optionally 'basic' can be passed for a set of predefined basic optimizations. Such 'basic' optimizations were used by default in old implementation, however they can be really slow on larger expressions. Now, no pre or post optimizations are made by default. postprocess : a function which accepts the two return values of cse and returns the desired form of output from cse, e.g. if you want the replacements reversed the function might be the following lambda: lambda r, e: return reversed(r), e order : string, 'none' or 'canonical' The order by which Mul and Add arguments are processed. If set to 'canonical', arguments will be canonically ordered. If set to 'none', ordering will be faster but dependent on expressions hashes, thus machine dependent and variable. For large expressions where speed is a concern, use the setting order='none'. ignore : iterable of Symbols Substitutions containing any Symbol from ``ignore`` will be ignored. list : bool, (default True) Returns expression in list or else with same type as input (when False). Returns ======= replacements : list of (Symbol, expression) pairs All of the common subexpressions that were replaced. Subexpressions earlier in this list might show up in subexpressions later in this list. reduced_exprs : list of sympy expressions The reduced expressions with all of the replacements above. Examples ======== >>> from sympy import cse, SparseMatrix >>> from sympy.abc import x, y, z, w >>> cse(((w + x + y + z)*(w + y + z))/(w + x)**3) ([(x0, y + z), (x1, w + x)], [(w + x0)*(x0 + x1)/x1**3]) Note that currently, y + z will not get substituted if -y - z is used. >>> cse(((w + x + y + z)*(w - y - z))/(w + x)**3) ([(x0, w + x)], [(w - y - z)*(x0 + y + z)/x0**3]) List of expressions with recursive substitutions: >>> m = SparseMatrix([x + y, x + y + z]) >>> cse([(x+y)**2, x + y + z, y + z, x + z + y, m]) ([(x0, x + y), (x1, x0 + z)], [x0**2, x1, y + z, x1, Matrix([ [x0], [x1]])]) Note: the type and mutability of input matrices is retained. >>> isinstance(_[1][-1], SparseMatrix) True The user may disallow substitutions containing certain symbols: >>> cse([y**2*(x + 1), 3*y**2*(x + 1)], ignore=(y,)) ([(x0, x + 1)], [x0*y**2, 3*x0*y**2]) The default return value for the reduced expression(s) is a list, even if there is only one expression. The `list` flag preserves the type of the input in the output: >>> cse(x) ([], [x]) >>> cse(x, list=False) ([], x) """ from sympy.matrices import (MatrixBase, Matrix, ImmutableMatrix, SparseMatrix, ImmutableSparseMatrix) if not list: return _cse_homogeneous(exprs, symbols=symbols, optimizations=optimizations, postprocess=postprocess, order=order, ignore=ignore) if isinstance(exprs, (int, float)): exprs = sympify(exprs) # Handle the case if just one expression was passed. if isinstance(exprs, (Basic, MatrixBase)): exprs = [exprs] copy = exprs temp = [] for e in exprs: if isinstance(e, (Matrix, ImmutableMatrix)): temp.append(Tuple(*e.flat())) elif isinstance(e, (SparseMatrix, ImmutableSparseMatrix)): temp.append(Tuple(*e.todok().items())) else: temp.append(e) exprs = temp del temp if optimizations is None: optimizations = [] elif optimizations == 'basic': optimizations = basic_optimizations # Preprocess the expressions to give us better optimization opportunities. reduced_exprs = [preprocess_for_cse(e, optimizations) for e in exprs] if symbols is None: symbols = numbered_symbols(cls=Symbol) else: # In case we get passed an iterable with an __iter__ method instead of # an actual iterator. symbols = iter(symbols) # Find other optimization opportunities. opt_subs = opt_cse(reduced_exprs, order) # Main CSE algorithm. replacements, reduced_exprs = tree_cse(reduced_exprs, symbols, opt_subs, order, ignore) # Postprocess the expressions to return the expressions to canonical form. exprs = copy for i, (sym, subtree) in enumerate(replacements): subtree = postprocess_for_cse(subtree, optimizations) replacements[i] = (sym, subtree) reduced_exprs = [postprocess_for_cse(e, optimizations) for e in reduced_exprs] # Get the matrices back for i, e in enumerate(exprs): if isinstance(e, (Matrix, ImmutableMatrix)): reduced_exprs[i] = Matrix(e.rows, e.cols, reduced_exprs[i]) if isinstance(e, ImmutableMatrix): reduced_exprs[i] = reduced_exprs[i].as_immutable() elif isinstance(e, (SparseMatrix, ImmutableSparseMatrix)): m = SparseMatrix(e.rows, e.cols, {}) for k, v in reduced_exprs[i]: m[k] = v if isinstance(e, ImmutableSparseMatrix): m = m.as_immutable() reduced_exprs[i] = m if postprocess is None: return replacements, reduced_exprs return postprocess(replacements, reduced_exprs) def _cse_homogeneous(exprs, **kwargs): """ Same as ``cse`` but the ``reduced_exprs`` are returned with the same type as ``exprs`` or a sympified version of the same. Parameters ========== exprs : an Expr, iterable of Expr or dictionary with Expr values the expressions in which repeated subexpressions will be identified kwargs : additional arguments for the ``cse`` function Returns ======= replacements : list of (Symbol, expression) pairs All of the common subexpressions that were replaced. Subexpressions earlier in this list might show up in subexpressions later in this list. reduced_exprs : list of sympy expressions The reduced expressions with all of the replacements above. Examples ======== >>> from sympy.simplify.cse_main import cse >>> from sympy import cos, Tuple, Matrix >>> from sympy.abc import x >>> output = lambda x: type(cse(x, list=False)[1]) >>> output(1) <class 'sympy.core.numbers.One'> >>> output('cos(x)') <class 'str'> >>> output(cos(x)) cos >>> output(Tuple(1, x)) <class 'sympy.core.containers.Tuple'> >>> output(Matrix([[1,0], [0,1]])) <class 'sympy.matrices.dense.MutableDenseMatrix'> >>> output([1, x]) <class 'list'> >>> output((1, x)) <class 'tuple'> >>> output({1, x}) <class 'set'> """ if isinstance(exprs, str): from sympy import sympify replacements, reduced_exprs = _cse_homogeneous( sympify(exprs), **kwargs) return replacements, repr(reduced_exprs) if isinstance(exprs, (list, tuple, set)): replacements, reduced_exprs = cse(exprs, **kwargs) return replacements, type(exprs)(reduced_exprs) if isinstance(exprs, dict): keys = list(exprs.keys()) # In order to guarantee the order of the elements. replacements, values = cse([exprs[k] for k in keys], **kwargs) reduced_exprs = dict(zip(keys, values)) return replacements, reduced_exprs try: replacements, (reduced_exprs,) = cse(exprs, **kwargs) except TypeError: # For example 'mpf' objects return [], exprs else: return replacements, reduced_exprs
52e87d15d522475998a0638495fb4ce8f8f1b9428f74e8fe24caa43a0789e98e
from collections import defaultdict from sympy.core.add import Add from sympy.core.basic import S from sympy.core.compatibility import ordered from sympy.core.expr import Expr from sympy.core.exprtools import Factors, gcd_terms, factor_terms from sympy.core.function import expand_mul from sympy.core.mul import Mul from sympy.core.numbers import pi, I from sympy.core.power import Pow from sympy.core.symbol import Dummy from sympy.core.sympify import sympify from sympy.functions.combinatorial.factorials import binomial from sympy.functions.elementary.hyperbolic import ( cosh, sinh, tanh, coth, sech, csch, HyperbolicFunction) from sympy.functions.elementary.trigonometric import ( cos, sin, tan, cot, sec, csc, sqrt, TrigonometricFunction) from sympy.ntheory.factor_ import perfect_power from sympy.polys.polytools import factor from sympy.simplify.simplify import bottom_up from sympy.strategies.tree import greedy from sympy.strategies.core import identity, debug from sympy import SYMPY_DEBUG # ================== Fu-like tools =========================== def TR0(rv): """Simplification of rational polynomials, trying to simplify the expression, e.g. combine things like 3*x + 2*x, etc.... """ # although it would be nice to use cancel, it doesn't work # with noncommutatives return rv.normal().factor().expand() def TR1(rv): """Replace sec, csc with 1/cos, 1/sin Examples ======== >>> from sympy.simplify.fu import TR1, sec, csc >>> from sympy.abc import x >>> TR1(2*csc(x) + sec(x)) 1/cos(x) + 2/sin(x) """ def f(rv): if isinstance(rv, sec): a = rv.args[0] return S.One/cos(a) elif isinstance(rv, csc): a = rv.args[0] return S.One/sin(a) return rv return bottom_up(rv, f) def TR2(rv): """Replace tan and cot with sin/cos and cos/sin Examples ======== >>> from sympy.simplify.fu import TR2 >>> from sympy.abc import x >>> from sympy import tan, cot, sin, cos >>> TR2(tan(x)) sin(x)/cos(x) >>> TR2(cot(x)) cos(x)/sin(x) >>> TR2(tan(tan(x) - sin(x)/cos(x))) 0 """ def f(rv): if isinstance(rv, tan): a = rv.args[0] return sin(a)/cos(a) elif isinstance(rv, cot): a = rv.args[0] return cos(a)/sin(a) return rv return bottom_up(rv, f) def TR2i(rv, half=False): """Converts ratios involving sin and cos as follows:: sin(x)/cos(x) -> tan(x) sin(x)/(cos(x) + 1) -> tan(x/2) if half=True Examples ======== >>> from sympy.simplify.fu import TR2i >>> from sympy.abc import x, a >>> from sympy import sin, cos >>> TR2i(sin(x)/cos(x)) tan(x) Powers of the numerator and denominator are also recognized >>> TR2i(sin(x)**2/(cos(x) + 1)**2, half=True) tan(x/2)**2 The transformation does not take place unless assumptions allow (i.e. the base must be positive or the exponent must be an integer for both numerator and denominator) >>> TR2i(sin(x)**a/(cos(x) + 1)**a) sin(x)**a/(cos(x) + 1)**a """ def f(rv): if not rv.is_Mul: return rv n, d = rv.as_numer_denom() if n.is_Atom or d.is_Atom: return rv def ok(k, e): # initial filtering of factors return ( (e.is_integer or k.is_positive) and ( k.func in (sin, cos) or (half and k.is_Add and len(k.args) >= 2 and any(any(isinstance(ai, cos) or ai.is_Pow and ai.base is cos for ai in Mul.make_args(a)) for a in k.args)))) n = n.as_powers_dict() ndone = [(k, n.pop(k)) for k in list(n.keys()) if not ok(k, n[k])] if not n: return rv d = d.as_powers_dict() ddone = [(k, d.pop(k)) for k in list(d.keys()) if not ok(k, d[k])] if not d: return rv # factoring if necessary def factorize(d, ddone): newk = [] for k in d: if k.is_Add and len(k.args) > 1: knew = factor(k) if half else factor_terms(k) if knew != k: newk.append((k, knew)) if newk: for i, (k, knew) in enumerate(newk): del d[k] newk[i] = knew newk = Mul(*newk).as_powers_dict() for k in newk: v = d[k] + newk[k] if ok(k, v): d[k] = v else: ddone.append((k, v)) del newk factorize(n, ndone) factorize(d, ddone) # joining t = [] for k in n: if isinstance(k, sin): a = cos(k.args[0], evaluate=False) if a in d and d[a] == n[k]: t.append(tan(k.args[0])**n[k]) n[k] = d[a] = None elif half: a1 = 1 + a if a1 in d and d[a1] == n[k]: t.append((tan(k.args[0]/2))**n[k]) n[k] = d[a1] = None elif isinstance(k, cos): a = sin(k.args[0], evaluate=False) if a in d and d[a] == n[k]: t.append(tan(k.args[0])**-n[k]) n[k] = d[a] = None elif half and k.is_Add and k.args[0] is S.One and \ isinstance(k.args[1], cos): a = sin(k.args[1].args[0], evaluate=False) if a in d and d[a] == n[k] and (d[a].is_integer or \ a.is_positive): t.append(tan(a.args[0]/2)**-n[k]) n[k] = d[a] = None if t: rv = Mul(*(t + [b**e for b, e in n.items() if e]))/\ Mul(*[b**e for b, e in d.items() if e]) rv *= Mul(*[b**e for b, e in ndone])/Mul(*[b**e for b, e in ddone]) return rv return bottom_up(rv, f) def TR3(rv): """Induced formula: example sin(-a) = -sin(a) Examples ======== >>> from sympy.simplify.fu import TR3 >>> from sympy.abc import x, y >>> from sympy import pi >>> from sympy import cos >>> TR3(cos(y - x*(y - x))) cos(x*(x - y) + y) >>> cos(pi/2 + x) -sin(x) >>> cos(30*pi/2 + x) -cos(x) """ from sympy.simplify.simplify import signsimp # Negative argument (already automatic for funcs like sin(-x) -> -sin(x) # but more complicated expressions can use it, too). Also, trig angles # between pi/4 and pi/2 are not reduced to an angle between 0 and pi/4. # The following are automatically handled: # Argument of type: pi/2 +/- angle # Argument of type: pi +/- angle # Argument of type : 2k*pi +/- angle def f(rv): if not isinstance(rv, TrigonometricFunction): return rv rv = rv.func(signsimp(rv.args[0])) if not isinstance(rv, TrigonometricFunction): return rv if (rv.args[0] - S.Pi/4).is_positive is (S.Pi/2 - rv.args[0]).is_positive is True: fmap = {cos: sin, sin: cos, tan: cot, cot: tan, sec: csc, csc: sec} rv = fmap[rv.func](S.Pi/2 - rv.args[0]) return rv return bottom_up(rv, f) def TR4(rv): """Identify values of special angles. a= 0 pi/6 pi/4 pi/3 pi/2 ---------------------------------------------------- sin(a) 0 1/2 sqrt(2)/2 sqrt(3)/2 1 cos(a) 1 sqrt(3)/2 sqrt(2)/2 1/2 0 tan(a) 0 sqt(3)/3 1 sqrt(3) -- Examples ======== >>> from sympy import pi >>> from sympy import cos, sin, tan, cot >>> for s in (0, pi/6, pi/4, pi/3, pi/2): ... print('%s %s %s %s' % (cos(s), sin(s), tan(s), cot(s))) ... 1 0 0 zoo sqrt(3)/2 1/2 sqrt(3)/3 sqrt(3) sqrt(2)/2 sqrt(2)/2 1 1 1/2 sqrt(3)/2 sqrt(3) sqrt(3)/3 0 1 zoo 0 """ # special values at 0, pi/6, pi/4, pi/3, pi/2 already handled return rv def _TR56(rv, f, g, h, max, pow): """Helper for TR5 and TR6 to replace f**2 with h(g**2) Options ======= max : controls size of exponent that can appear on f e.g. if max=4 then f**4 will be changed to h(g**2)**2. pow : controls whether the exponent must be a perfect power of 2 e.g. if pow=True (and max >= 6) then f**6 will not be changed but f**8 will be changed to h(g**2)**4 >>> from sympy.simplify.fu import _TR56 as T >>> from sympy.abc import x >>> from sympy import sin, cos >>> h = lambda x: 1 - x >>> T(sin(x)**3, sin, cos, h, 4, False) (1 - cos(x)**2)*sin(x) >>> T(sin(x)**6, sin, cos, h, 6, False) (1 - cos(x)**2)**3 >>> T(sin(x)**6, sin, cos, h, 6, True) sin(x)**6 >>> T(sin(x)**8, sin, cos, h, 10, True) (1 - cos(x)**2)**4 """ def _f(rv): # I'm not sure if this transformation should target all even powers # or only those expressible as powers of 2. Also, should it only # make the changes in powers that appear in sums -- making an isolated # change is not going to allow a simplification as far as I can tell. if not (rv.is_Pow and rv.base.func == f): return rv if not rv.exp.is_real: return rv if (rv.exp < 0) == True: return rv if (rv.exp > max) == True: return rv if rv.exp == 1: return rv if rv.exp == 2: return h(g(rv.base.args[0])**2) else: if rv.exp % 2 == 1: e = rv.exp//2 return f(rv.base.args[0])*h(g(rv.base.args[0])**2)**e elif rv.exp == 4: e = 2 elif not pow: if rv.exp % 2: return rv e = rv.exp//2 else: p = perfect_power(rv.exp) if not p: return rv e = rv.exp//2 return h(g(rv.base.args[0])**2)**e return bottom_up(rv, _f) def TR5(rv, max=4, pow=False): """Replacement of sin**2 with 1 - cos(x)**2. See _TR56 docstring for advanced use of ``max`` and ``pow``. Examples ======== >>> from sympy.simplify.fu import TR5 >>> from sympy.abc import x >>> from sympy import sin >>> TR5(sin(x)**2) 1 - cos(x)**2 >>> TR5(sin(x)**-2) # unchanged sin(x)**(-2) >>> TR5(sin(x)**4) (1 - cos(x)**2)**2 """ return _TR56(rv, sin, cos, lambda x: 1 - x, max=max, pow=pow) def TR6(rv, max=4, pow=False): """Replacement of cos**2 with 1 - sin(x)**2. See _TR56 docstring for advanced use of ``max`` and ``pow``. Examples ======== >>> from sympy.simplify.fu import TR6 >>> from sympy.abc import x >>> from sympy import cos >>> TR6(cos(x)**2) 1 - sin(x)**2 >>> TR6(cos(x)**-2) #unchanged cos(x)**(-2) >>> TR6(cos(x)**4) (1 - sin(x)**2)**2 """ return _TR56(rv, cos, sin, lambda x: 1 - x, max=max, pow=pow) def TR7(rv): """Lowering the degree of cos(x)**2. Examples ======== >>> from sympy.simplify.fu import TR7 >>> from sympy.abc import x >>> from sympy import cos >>> TR7(cos(x)**2) cos(2*x)/2 + 1/2 >>> TR7(cos(x)**2 + 1) cos(2*x)/2 + 3/2 """ def f(rv): if not (rv.is_Pow and rv.base.func == cos and rv.exp == 2): return rv return (1 + cos(2*rv.base.args[0]))/2 return bottom_up(rv, f) def TR8(rv, first=True): """Converting products of ``cos`` and/or ``sin`` to a sum or difference of ``cos`` and or ``sin`` terms. Examples ======== >>> from sympy.simplify.fu import TR8 >>> from sympy import cos, sin >>> TR8(cos(2)*cos(3)) cos(5)/2 + cos(1)/2 >>> TR8(cos(2)*sin(3)) sin(5)/2 + sin(1)/2 >>> TR8(sin(2)*sin(3)) -cos(5)/2 + cos(1)/2 """ def f(rv): if not ( rv.is_Mul or rv.is_Pow and rv.base.func in (cos, sin) and (rv.exp.is_integer or rv.base.is_positive)): return rv if first: n, d = [expand_mul(i) for i in rv.as_numer_denom()] newn = TR8(n, first=False) newd = TR8(d, first=False) if newn != n or newd != d: rv = gcd_terms(newn/newd) if rv.is_Mul and rv.args[0].is_Rational and \ len(rv.args) == 2 and rv.args[1].is_Add: rv = Mul(*rv.as_coeff_Mul()) return rv args = {cos: [], sin: [], None: []} for a in ordered(Mul.make_args(rv)): if a.func in (cos, sin): args[a.func].append(a.args[0]) elif (a.is_Pow and a.exp.is_Integer and a.exp > 0 and \ a.base.func in (cos, sin)): # XXX this is ok but pathological expression could be handled # more efficiently as in TRmorrie args[a.base.func].extend([a.base.args[0]]*a.exp) else: args[None].append(a) c = args[cos] s = args[sin] if not (c and s or len(c) > 1 or len(s) > 1): return rv args = args[None] n = min(len(c), len(s)) for i in range(n): a1 = s.pop() a2 = c.pop() args.append((sin(a1 + a2) + sin(a1 - a2))/2) while len(c) > 1: a1 = c.pop() a2 = c.pop() args.append((cos(a1 + a2) + cos(a1 - a2))/2) if c: args.append(cos(c.pop())) while len(s) > 1: a1 = s.pop() a2 = s.pop() args.append((-cos(a1 + a2) + cos(a1 - a2))/2) if s: args.append(sin(s.pop())) return TR8(expand_mul(Mul(*args))) return bottom_up(rv, f) def TR9(rv): """Sum of ``cos`` or ``sin`` terms as a product of ``cos`` or ``sin``. Examples ======== >>> from sympy.simplify.fu import TR9 >>> from sympy import cos, sin >>> TR9(cos(1) + cos(2)) 2*cos(1/2)*cos(3/2) >>> TR9(cos(1) + 2*sin(1) + 2*sin(2)) cos(1) + 4*sin(3/2)*cos(1/2) If no change is made by TR9, no re-arrangement of the expression will be made. For example, though factoring of common term is attempted, if the factored expression wasn't changed, the original expression will be returned: >>> TR9(cos(3) + cos(3)*cos(2)) cos(3) + cos(2)*cos(3) """ def f(rv): if not rv.is_Add: return rv def do(rv, first=True): # cos(a)+/-cos(b) can be combined into a product of cosines and # sin(a)+/-sin(b) can be combined into a product of cosine and # sine. # # If there are more than two args, the pairs which "work" will # have a gcd extractable and the remaining two terms will have # the above structure -- all pairs must be checked to find the # ones that work. args that don't have a common set of symbols # are skipped since this doesn't lead to a simpler formula and # also has the arbitrariness of combining, for example, the x # and y term instead of the y and z term in something like # cos(x) + cos(y) + cos(z). if not rv.is_Add: return rv args = list(ordered(rv.args)) if len(args) != 2: hit = False for i in range(len(args)): ai = args[i] if ai is None: continue for j in range(i + 1, len(args)): aj = args[j] if aj is None: continue was = ai + aj new = do(was) if new != was: args[i] = new # update in place args[j] = None hit = True break # go to next i if hit: rv = Add(*[_f for _f in args if _f]) if rv.is_Add: rv = do(rv) return rv # two-arg Add split = trig_split(*args) if not split: return rv gcd, n1, n2, a, b, iscos = split # application of rule if possible if iscos: if n1 == n2: return gcd*n1*2*cos((a + b)/2)*cos((a - b)/2) if n1 < 0: a, b = b, a return -2*gcd*sin((a + b)/2)*sin((a - b)/2) else: if n1 == n2: return gcd*n1*2*sin((a + b)/2)*cos((a - b)/2) if n1 < 0: a, b = b, a return 2*gcd*cos((a + b)/2)*sin((a - b)/2) return process_common_addends(rv, do) # DON'T sift by free symbols return bottom_up(rv, f) def TR10(rv, first=True): """Separate sums in ``cos`` and ``sin``. Examples ======== >>> from sympy.simplify.fu import TR10 >>> from sympy.abc import a, b, c >>> from sympy import cos, sin >>> TR10(cos(a + b)) -sin(a)*sin(b) + cos(a)*cos(b) >>> TR10(sin(a + b)) sin(a)*cos(b) + sin(b)*cos(a) >>> TR10(sin(a + b + c)) (-sin(a)*sin(b) + cos(a)*cos(b))*sin(c) + \ (sin(a)*cos(b) + sin(b)*cos(a))*cos(c) """ def f(rv): if not rv.func in (cos, sin): return rv f = rv.func arg = rv.args[0] if arg.is_Add: if first: args = list(ordered(arg.args)) else: args = list(arg.args) a = args.pop() b = Add._from_args(args) if b.is_Add: if f == sin: return sin(a)*TR10(cos(b), first=False) + \ cos(a)*TR10(sin(b), first=False) else: return cos(a)*TR10(cos(b), first=False) - \ sin(a)*TR10(sin(b), first=False) else: if f == sin: return sin(a)*cos(b) + cos(a)*sin(b) else: return cos(a)*cos(b) - sin(a)*sin(b) return rv return bottom_up(rv, f) def TR10i(rv): """Sum of products to function of sum. Examples ======== >>> from sympy.simplify.fu import TR10i >>> from sympy import cos, sin, sqrt >>> from sympy.abc import x >>> TR10i(cos(1)*cos(3) + sin(1)*sin(3)) cos(2) >>> TR10i(cos(1)*sin(3) + sin(1)*cos(3) + cos(3)) cos(3) + sin(4) >>> TR10i(sqrt(2)*cos(x)*x + sqrt(6)*sin(x)*x) 2*sqrt(2)*x*sin(x + pi/6) """ global _ROOT2, _ROOT3, _invROOT3 if _ROOT2 is None: _roots() def f(rv): if not rv.is_Add: return rv def do(rv, first=True): # args which can be expressed as A*(cos(a)*cos(b)+/-sin(a)*sin(b)) # or B*(cos(a)*sin(b)+/-cos(b)*sin(a)) can be combined into # A*f(a+/-b) where f is either sin or cos. # # If there are more than two args, the pairs which "work" will have # a gcd extractable and the remaining two terms will have the above # structure -- all pairs must be checked to find the ones that # work. if not rv.is_Add: return rv args = list(ordered(rv.args)) if len(args) != 2: hit = False for i in range(len(args)): ai = args[i] if ai is None: continue for j in range(i + 1, len(args)): aj = args[j] if aj is None: continue was = ai + aj new = do(was) if new != was: args[i] = new # update in place args[j] = None hit = True break # go to next i if hit: rv = Add(*[_f for _f in args if _f]) if rv.is_Add: rv = do(rv) return rv # two-arg Add split = trig_split(*args, two=True) if not split: return rv gcd, n1, n2, a, b, same = split # identify and get c1 to be cos then apply rule if possible if same: # coscos, sinsin gcd = n1*gcd if n1 == n2: return gcd*cos(a - b) return gcd*cos(a + b) else: #cossin, cossin gcd = n1*gcd if n1 == n2: return gcd*sin(a + b) return gcd*sin(b - a) rv = process_common_addends( rv, do, lambda x: tuple(ordered(x.free_symbols))) # need to check for inducible pairs in ratio of sqrt(3):1 that # appeared in different lists when sorting by coefficient while rv.is_Add: byrad = defaultdict(list) for a in rv.args: hit = 0 if a.is_Mul: for ai in a.args: if ai.is_Pow and ai.exp is S.Half and \ ai.base.is_Integer: byrad[ai].append(a) hit = 1 break if not hit: byrad[S.One].append(a) # no need to check all pairs -- just check for the onees # that have the right ratio args = [] for a in byrad: for b in [_ROOT3*a, _invROOT3]: if b in byrad: for i in range(len(byrad[a])): if byrad[a][i] is None: continue for j in range(len(byrad[b])): if byrad[b][j] is None: continue was = Add(byrad[a][i] + byrad[b][j]) new = do(was) if new != was: args.append(new) byrad[a][i] = None byrad[b][j] = None break if args: rv = Add(*(args + [Add(*[_f for _f in v if _f]) for v in byrad.values()])) else: rv = do(rv) # final pass to resolve any new inducible pairs break return rv return bottom_up(rv, f) def TR11(rv, base=None): """Function of double angle to product. The ``base`` argument can be used to indicate what is the un-doubled argument, e.g. if 3*pi/7 is the base then cosine and sine functions with argument 6*pi/7 will be replaced. Examples ======== >>> from sympy.simplify.fu import TR11 >>> from sympy import cos, sin, pi >>> from sympy.abc import x >>> TR11(sin(2*x)) 2*sin(x)*cos(x) >>> TR11(cos(2*x)) -sin(x)**2 + cos(x)**2 >>> TR11(sin(4*x)) 4*(-sin(x)**2 + cos(x)**2)*sin(x)*cos(x) >>> TR11(sin(4*x/3)) 4*(-sin(x/3)**2 + cos(x/3)**2)*sin(x/3)*cos(x/3) If the arguments are simply integers, no change is made unless a base is provided: >>> TR11(cos(2)) cos(2) >>> TR11(cos(4), 2) -sin(2)**2 + cos(2)**2 There is a subtle issue here in that autosimplification will convert some higher angles to lower angles >>> cos(6*pi/7) + cos(3*pi/7) -cos(pi/7) + cos(3*pi/7) The 6*pi/7 angle is now pi/7 but can be targeted with TR11 by supplying the 3*pi/7 base: >>> TR11(_, 3*pi/7) -sin(3*pi/7)**2 + cos(3*pi/7)**2 + cos(3*pi/7) """ def f(rv): if not rv.func in (cos, sin): return rv if base: f = rv.func t = f(base*2) co = S.One if t.is_Mul: co, t = t.as_coeff_Mul() if not t.func in (cos, sin): return rv if rv.args[0] == t.args[0]: c = cos(base) s = sin(base) if f is cos: return (c**2 - s**2)/co else: return 2*c*s/co return rv elif not rv.args[0].is_Number: # make a change if the leading coefficient's numerator is # divisible by 2 c, m = rv.args[0].as_coeff_Mul(rational=True) if c.p % 2 == 0: arg = c.p//2*m/c.q c = TR11(cos(arg)) s = TR11(sin(arg)) if rv.func == sin: rv = 2*s*c else: rv = c**2 - s**2 return rv return bottom_up(rv, f) def _TR11(rv): """ Helper for TR11 to find half-arguments for sin in factors of num/den that appear in cos or sin factors in the den/num. Examples ======== >>> from sympy.simplify.fu import TR11, _TR11 >>> from sympy import cos, sin >>> from sympy.abc import x >>> TR11(sin(x/3)/(cos(x/6))) sin(x/3)/cos(x/6) >>> _TR11(sin(x/3)/(cos(x/6))) 2*sin(x/6) >>> TR11(sin(x/6)/(sin(x/3))) sin(x/6)/sin(x/3) >>> _TR11(sin(x/6)/(sin(x/3))) 1/(2*cos(x/6)) """ def f(rv): if not isinstance(rv, Expr): return rv def sincos_args(flat): # find arguments of sin and cos that # appears as bases in args of flat # and have Integer exponents args = defaultdict(set) for fi in Mul.make_args(flat): b, e = fi.as_base_exp() if e.is_Integer and e > 0: if b.func in (cos, sin): args[b.func].add(b.args[0]) return args num_args, den_args = map(sincos_args, rv.as_numer_denom()) def handle_match(rv, num_args, den_args): # for arg in sin args of num_args, look for arg/2 # in den_args and pass this half-angle to TR11 # for handling in rv for narg in num_args[sin]: half = narg/2 if half in den_args[cos]: func = cos elif half in den_args[sin]: func = sin else: continue rv = TR11(rv, half) den_args[func].remove(half) return rv # sin in num, sin or cos in den rv = handle_match(rv, num_args, den_args) # sin in den, sin or cos in num rv = handle_match(rv, den_args, num_args) return rv return bottom_up(rv, f) def TR12(rv, first=True): """Separate sums in ``tan``. Examples ======== >>> from sympy.abc import x, y >>> from sympy import tan >>> from sympy.simplify.fu import TR12 >>> TR12(tan(x + y)) (tan(x) + tan(y))/(-tan(x)*tan(y) + 1) """ def f(rv): if not rv.func == tan: return rv arg = rv.args[0] if arg.is_Add: if first: args = list(ordered(arg.args)) else: args = list(arg.args) a = args.pop() b = Add._from_args(args) if b.is_Add: tb = TR12(tan(b), first=False) else: tb = tan(b) return (tan(a) + tb)/(1 - tan(a)*tb) return rv return bottom_up(rv, f) def TR12i(rv): """Combine tan arguments as (tan(y) + tan(x))/(tan(x)*tan(y) - 1) -> -tan(x + y). Examples ======== >>> from sympy.simplify.fu import TR12i >>> from sympy import tan >>> from sympy.abc import a, b, c >>> ta, tb, tc = [tan(i) for i in (a, b, c)] >>> TR12i((ta + tb)/(-ta*tb + 1)) tan(a + b) >>> TR12i((ta + tb)/(ta*tb - 1)) -tan(a + b) >>> TR12i((-ta - tb)/(ta*tb - 1)) tan(a + b) >>> eq = (ta + tb)/(-ta*tb + 1)**2*(-3*ta - 3*tc)/(2*(ta*tc - 1)) >>> TR12i(eq.expand()) -3*tan(a + b)*tan(a + c)/(2*(tan(a) + tan(b) - 1)) """ from sympy import factor def f(rv): if not (rv.is_Add or rv.is_Mul or rv.is_Pow): return rv n, d = rv.as_numer_denom() if not d.args or not n.args: return rv dok = {} def ok(di): m = as_f_sign_1(di) if m: g, f, s = m if s is S.NegativeOne and f.is_Mul and len(f.args) == 2 and \ all(isinstance(fi, tan) for fi in f.args): return g, f d_args = list(Mul.make_args(d)) for i, di in enumerate(d_args): m = ok(di) if m: g, t = m s = Add(*[_.args[0] for _ in t.args]) dok[s] = S.One d_args[i] = g continue if di.is_Add: di = factor(di) if di.is_Mul: d_args.extend(di.args) d_args[i] = S.One elif di.is_Pow and (di.exp.is_integer or di.base.is_positive): m = ok(di.base) if m: g, t = m s = Add(*[_.args[0] for _ in t.args]) dok[s] = di.exp d_args[i] = g**di.exp else: di = factor(di) if di.is_Mul: d_args.extend(di.args) d_args[i] = S.One if not dok: return rv def ok(ni): if ni.is_Add and len(ni.args) == 2: a, b = ni.args if isinstance(a, tan) and isinstance(b, tan): return a, b n_args = list(Mul.make_args(factor_terms(n))) hit = False for i, ni in enumerate(n_args): m = ok(ni) if not m: m = ok(-ni) if m: n_args[i] = S.NegativeOne else: if ni.is_Add: ni = factor(ni) if ni.is_Mul: n_args.extend(ni.args) n_args[i] = S.One continue elif ni.is_Pow and ( ni.exp.is_integer or ni.base.is_positive): m = ok(ni.base) if m: n_args[i] = S.One else: ni = factor(ni) if ni.is_Mul: n_args.extend(ni.args) n_args[i] = S.One continue else: continue else: n_args[i] = S.One hit = True s = Add(*[_.args[0] for _ in m]) ed = dok[s] newed = ed.extract_additively(S.One) if newed is not None: if newed: dok[s] = newed else: dok.pop(s) n_args[i] *= -tan(s) if hit: rv = Mul(*n_args)/Mul(*d_args)/Mul(*[(Add(*[ tan(a) for a in i.args]) - 1)**e for i, e in dok.items()]) return rv return bottom_up(rv, f) def TR13(rv): """Change products of ``tan`` or ``cot``. Examples ======== >>> from sympy.simplify.fu import TR13 >>> from sympy import tan, cot >>> TR13(tan(3)*tan(2)) -tan(2)/tan(5) - tan(3)/tan(5) + 1 >>> TR13(cot(3)*cot(2)) cot(2)*cot(5) + 1 + cot(3)*cot(5) """ def f(rv): if not rv.is_Mul: return rv # XXX handle products of powers? or let power-reducing handle it? args = {tan: [], cot: [], None: []} for a in ordered(Mul.make_args(rv)): if a.func in (tan, cot): args[a.func].append(a.args[0]) else: args[None].append(a) t = args[tan] c = args[cot] if len(t) < 2 and len(c) < 2: return rv args = args[None] while len(t) > 1: t1 = t.pop() t2 = t.pop() args.append(1 - (tan(t1)/tan(t1 + t2) + tan(t2)/tan(t1 + t2))) if t: args.append(tan(t.pop())) while len(c) > 1: t1 = c.pop() t2 = c.pop() args.append(1 + cot(t1)*cot(t1 + t2) + cot(t2)*cot(t1 + t2)) if c: args.append(cot(c.pop())) return Mul(*args) return bottom_up(rv, f) def TRmorrie(rv): """Returns cos(x)*cos(2*x)*...*cos(2**(k-1)*x) -> sin(2**k*x)/(2**k*sin(x)) Examples ======== >>> from sympy.simplify.fu import TRmorrie, TR8, TR3 >>> from sympy.abc import x >>> from sympy import Mul, cos, pi >>> TRmorrie(cos(x)*cos(2*x)) sin(4*x)/(4*sin(x)) >>> TRmorrie(7*Mul(*[cos(x) for x in range(10)])) 7*sin(12)*sin(16)*cos(5)*cos(7)*cos(9)/(64*sin(1)*sin(3)) Sometimes autosimplification will cause a power to be not recognized. e.g. in the following, cos(4*pi/7) automatically simplifies to -cos(3*pi/7) so only 2 of the 3 terms are recognized: >>> TRmorrie(cos(pi/7)*cos(2*pi/7)*cos(4*pi/7)) -sin(3*pi/7)*cos(3*pi/7)/(4*sin(pi/7)) A touch by TR8 resolves the expression to a Rational >>> TR8(_) -1/8 In this case, if eq is unsimplified, the answer is obtained directly: >>> eq = cos(pi/9)*cos(2*pi/9)*cos(3*pi/9)*cos(4*pi/9) >>> TRmorrie(eq) 1/16 But if angles are made canonical with TR3 then the answer is not simplified without further work: >>> TR3(eq) sin(pi/18)*cos(pi/9)*cos(2*pi/9)/2 >>> TRmorrie(_) sin(pi/18)*sin(4*pi/9)/(8*sin(pi/9)) >>> TR8(_) cos(7*pi/18)/(16*sin(pi/9)) >>> TR3(_) 1/16 The original expression would have resolve to 1/16 directly with TR8, however: >>> TR8(eq) 1/16 References ========== .. [1] https://en.wikipedia.org/wiki/Morrie%27s_law """ def f(rv, first=True): if not rv.is_Mul: return rv if first: n, d = rv.as_numer_denom() return f(n, 0)/f(d, 0) args = defaultdict(list) coss = {} other = [] for c in rv.args: b, e = c.as_base_exp() if e.is_Integer and isinstance(b, cos): co, a = b.args[0].as_coeff_Mul() args[a].append(co) coss[b] = e else: other.append(c) new = [] for a in args: c = args[a] c.sort() while c: k = 0 cc = ci = c[0] while cc in c: k += 1 cc *= 2 if k > 1: newarg = sin(2**k*ci*a)/2**k/sin(ci*a) # see how many times this can be taken take = None ccs = [] for i in range(k): cc /= 2 key = cos(a*cc, evaluate=False) ccs.append(cc) take = min(coss[key], take or coss[key]) # update exponent counts for i in range(k): cc = ccs.pop() key = cos(a*cc, evaluate=False) coss[key] -= take if not coss[key]: c.remove(cc) new.append(newarg**take) else: b = cos(c.pop(0)*a) other.append(b**coss[b]) if new: rv = Mul(*(new + other + [ cos(k*a, evaluate=False) for a in args for k in args[a]])) return rv return bottom_up(rv, f) def TR14(rv, first=True): """Convert factored powers of sin and cos identities into simpler expressions. Examples ======== >>> from sympy.simplify.fu import TR14 >>> from sympy.abc import x, y >>> from sympy import cos, sin >>> TR14((cos(x) - 1)*(cos(x) + 1)) -sin(x)**2 >>> TR14((sin(x) - 1)*(sin(x) + 1)) -cos(x)**2 >>> p1 = (cos(x) + 1)*(cos(x) - 1) >>> p2 = (cos(y) - 1)*2*(cos(y) + 1) >>> p3 = (3*(cos(y) - 1))*(3*(cos(y) + 1)) >>> TR14(p1*p2*p3*(x - 1)) -18*(x - 1)*sin(x)**2*sin(y)**4 """ def f(rv): if not rv.is_Mul: return rv if first: # sort them by location in numerator and denominator # so the code below can just deal with positive exponents n, d = rv.as_numer_denom() if d is not S.One: newn = TR14(n, first=False) newd = TR14(d, first=False) if newn != n or newd != d: rv = newn/newd return rv other = [] process = [] for a in rv.args: if a.is_Pow: b, e = a.as_base_exp() if not (e.is_integer or b.is_positive): other.append(a) continue a = b else: e = S.One m = as_f_sign_1(a) if not m or m[1].func not in (cos, sin): if e is S.One: other.append(a) else: other.append(a**e) continue g, f, si = m process.append((g, e.is_Number, e, f, si, a)) # sort them to get like terms next to each other process = list(ordered(process)) # keep track of whether there was any change nother = len(other) # access keys keys = (g, t, e, f, si, a) = list(range(6)) while process: A = process.pop(0) if process: B = process[0] if A[e].is_Number and B[e].is_Number: # both exponents are numbers if A[f] == B[f]: if A[si] != B[si]: B = process.pop(0) take = min(A[e], B[e]) # reinsert any remainder # the B will likely sort after A so check it first if B[e] != take: rem = [B[i] for i in keys] rem[e] -= take process.insert(0, rem) elif A[e] != take: rem = [A[i] for i in keys] rem[e] -= take process.insert(0, rem) if isinstance(A[f], cos): t = sin else: t = cos other.append((-A[g]*B[g]*t(A[f].args[0])**2)**take) continue elif A[e] == B[e]: # both exponents are equal symbols if A[f] == B[f]: if A[si] != B[si]: B = process.pop(0) take = A[e] if isinstance(A[f], cos): t = sin else: t = cos other.append((-A[g]*B[g]*t(A[f].args[0])**2)**take) continue # either we are done or neither condition above applied other.append(A[a]**A[e]) if len(other) != nother: rv = Mul(*other) return rv return bottom_up(rv, f) def TR15(rv, max=4, pow=False): """Convert sin(x)**-2 to 1 + cot(x)**2. See _TR56 docstring for advanced use of ``max`` and ``pow``. Examples ======== >>> from sympy.simplify.fu import TR15 >>> from sympy.abc import x >>> from sympy import sin >>> TR15(1 - 1/sin(x)**2) -cot(x)**2 """ def f(rv): if not (isinstance(rv, Pow) and isinstance(rv.base, sin)): return rv e = rv.exp if e % 2 == 1: return TR15(rv.base**(e + 1))/rv.base ia = 1/rv a = _TR56(ia, sin, cot, lambda x: 1 + x, max=max, pow=pow) if a != ia: rv = a return rv return bottom_up(rv, f) def TR16(rv, max=4, pow=False): """Convert cos(x)**-2 to 1 + tan(x)**2. See _TR56 docstring for advanced use of ``max`` and ``pow``. Examples ======== >>> from sympy.simplify.fu import TR16 >>> from sympy.abc import x >>> from sympy import cos >>> TR16(1 - 1/cos(x)**2) -tan(x)**2 """ def f(rv): if not (isinstance(rv, Pow) and isinstance(rv.base, cos)): return rv e = rv.exp if e % 2 == 1: return TR15(rv.base**(e + 1))/rv.base ia = 1/rv a = _TR56(ia, cos, tan, lambda x: 1 + x, max=max, pow=pow) if a != ia: rv = a return rv return bottom_up(rv, f) def TR111(rv): """Convert f(x)**-i to g(x)**i where either ``i`` is an integer or the base is positive and f, g are: tan, cot; sin, csc; or cos, sec. Examples ======== >>> from sympy.simplify.fu import TR111 >>> from sympy.abc import x >>> from sympy import tan >>> TR111(1 - 1/tan(x)**2) 1 - cot(x)**2 """ def f(rv): if not ( isinstance(rv, Pow) and (rv.base.is_positive or rv.exp.is_integer and rv.exp.is_negative)): return rv if isinstance(rv.base, tan): return cot(rv.base.args[0])**-rv.exp elif isinstance(rv.base, sin): return csc(rv.base.args[0])**-rv.exp elif isinstance(rv.base, cos): return sec(rv.base.args[0])**-rv.exp return rv return bottom_up(rv, f) def TR22(rv, max=4, pow=False): """Convert tan(x)**2 to sec(x)**2 - 1 and cot(x)**2 to csc(x)**2 - 1. See _TR56 docstring for advanced use of ``max`` and ``pow``. Examples ======== >>> from sympy.simplify.fu import TR22 >>> from sympy.abc import x >>> from sympy import tan, cot >>> TR22(1 + tan(x)**2) sec(x)**2 >>> TR22(1 + cot(x)**2) csc(x)**2 """ def f(rv): if not (isinstance(rv, Pow) and rv.base.func in (cot, tan)): return rv rv = _TR56(rv, tan, sec, lambda x: x - 1, max=max, pow=pow) rv = _TR56(rv, cot, csc, lambda x: x - 1, max=max, pow=pow) return rv return bottom_up(rv, f) def TRpower(rv): """Convert sin(x)**n and cos(x)**n with positive n to sums. Examples ======== >>> from sympy.simplify.fu import TRpower >>> from sympy.abc import x >>> from sympy import cos, sin >>> TRpower(sin(x)**6) -15*cos(2*x)/32 + 3*cos(4*x)/16 - cos(6*x)/32 + 5/16 >>> TRpower(sin(x)**3*cos(2*x)**4) (3*sin(x)/4 - sin(3*x)/4)*(cos(4*x)/2 + cos(8*x)/8 + 3/8) References ========== .. [1] https://en.wikipedia.org/wiki/List_of_trigonometric_identities#Power-reduction_formulae """ def f(rv): if not (isinstance(rv, Pow) and isinstance(rv.base, (sin, cos))): return rv b, n = rv.as_base_exp() x = b.args[0] if n.is_Integer and n.is_positive: if n.is_odd and isinstance(b, cos): rv = 2**(1-n)*Add(*[binomial(n, k)*cos((n - 2*k)*x) for k in range((n + 1)/2)]) elif n.is_odd and isinstance(b, sin): rv = 2**(1-n)*(-1)**((n-1)/2)*Add(*[binomial(n, k)* (-1)**k*sin((n - 2*k)*x) for k in range((n + 1)/2)]) elif n.is_even and isinstance(b, cos): rv = 2**(1-n)*Add(*[binomial(n, k)*cos((n - 2*k)*x) for k in range(n/2)]) elif n.is_even and isinstance(b, sin): rv = 2**(1-n)*(-1)**(n/2)*Add(*[binomial(n, k)* (-1)**k*cos((n - 2*k)*x) for k in range(n/2)]) if n.is_even: rv += 2**(-n)*binomial(n, n/2) return rv return bottom_up(rv, f) def L(rv): """Return count of trigonometric functions in expression. Examples ======== >>> from sympy.simplify.fu import L >>> from sympy.abc import x >>> from sympy import cos, sin >>> L(cos(x)+sin(x)) 2 """ return S(rv.count(TrigonometricFunction)) # ============== end of basic Fu-like tools ===================== if SYMPY_DEBUG: (TR0, TR1, TR2, TR3, TR4, TR5, TR6, TR7, TR8, TR9, TR10, TR11, TR12, TR13, TR2i, TRmorrie, TR14, TR15, TR16, TR12i, TR111, TR22 )= list(map(debug, (TR0, TR1, TR2, TR3, TR4, TR5, TR6, TR7, TR8, TR9, TR10, TR11, TR12, TR13, TR2i, TRmorrie, TR14, TR15, TR16, TR12i, TR111, TR22))) # tuples are chains -- (f, g) -> lambda x: g(f(x)) # lists are choices -- [f, g] -> lambda x: min(f(x), g(x), key=objective) CTR1 = [(TR5, TR0), (TR6, TR0), identity] CTR2 = (TR11, [(TR5, TR0), (TR6, TR0), TR0]) CTR3 = [(TRmorrie, TR8, TR0), (TRmorrie, TR8, TR10i, TR0), identity] CTR4 = [(TR4, TR10i), identity] RL1 = (TR4, TR3, TR4, TR12, TR4, TR13, TR4, TR0) # XXX it's a little unclear how this one is to be implemented # see Fu paper of reference, page 7. What is the Union symbol referring to? # The diagram shows all these as one chain of transformations, but the # text refers to them being applied independently. Also, a break # if L starts to increase has not been implemented. RL2 = [ (TR4, TR3, TR10, TR4, TR3, TR11), (TR5, TR7, TR11, TR4), (CTR3, CTR1, TR9, CTR2, TR4, TR9, TR9, CTR4), identity, ] def fu(rv, measure=lambda x: (L(x), x.count_ops())): """Attempt to simplify expression by using transformation rules given in the algorithm by Fu et al. :func:`fu` will try to minimize the objective function ``measure``. By default this first minimizes the number of trig terms and then minimizes the number of total operations. Examples ======== >>> from sympy.simplify.fu import fu >>> from sympy import cos, sin, tan, pi, S, sqrt >>> from sympy.abc import x, y, a, b >>> fu(sin(50)**2 + cos(50)**2 + sin(pi/6)) 3/2 >>> fu(sqrt(6)*cos(x) + sqrt(2)*sin(x)) 2*sqrt(2)*sin(x + pi/3) CTR1 example >>> eq = sin(x)**4 - cos(y)**2 + sin(y)**2 + 2*cos(x)**2 >>> fu(eq) cos(x)**4 - 2*cos(y)**2 + 2 CTR2 example >>> fu(S.Half - cos(2*x)/2) sin(x)**2 CTR3 example >>> fu(sin(a)*(cos(b) - sin(b)) + cos(a)*(sin(b) + cos(b))) sqrt(2)*sin(a + b + pi/4) CTR4 example >>> fu(sqrt(3)*cos(x)/2 + sin(x)/2) sin(x + pi/3) Example 1 >>> fu(1-sin(2*x)**2/4-sin(y)**2-cos(x)**4) -cos(x)**2 + cos(y)**2 Example 2 >>> fu(cos(4*pi/9)) sin(pi/18) >>> fu(cos(pi/9)*cos(2*pi/9)*cos(3*pi/9)*cos(4*pi/9)) 1/16 Example 3 >>> fu(tan(7*pi/18)+tan(5*pi/18)-sqrt(3)*tan(5*pi/18)*tan(7*pi/18)) -sqrt(3) Objective function example >>> fu(sin(x)/cos(x)) # default objective function tan(x) >>> fu(sin(x)/cos(x), measure=lambda x: -x.count_ops()) # maximize op count sin(x)/cos(x) References ========== .. [1] https://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.657.2478&rep=rep1&type=pdf """ fRL1 = greedy(RL1, measure) fRL2 = greedy(RL2, measure) was = rv rv = sympify(rv) if not isinstance(rv, Expr): return rv.func(*[fu(a, measure=measure) for a in rv.args]) rv = TR1(rv) if rv.has(tan, cot): rv1 = fRL1(rv) if (measure(rv1) < measure(rv)): rv = rv1 if rv.has(tan, cot): rv = TR2(rv) if rv.has(sin, cos): rv1 = fRL2(rv) rv2 = TR8(TRmorrie(rv1)) rv = min([was, rv, rv1, rv2], key=measure) return min(TR2i(rv), rv, key=measure) def process_common_addends(rv, do, key2=None, key1=True): """Apply ``do`` to addends of ``rv`` that (if ``key1=True``) share at least a common absolute value of their coefficient and the value of ``key2`` when applied to the argument. If ``key1`` is False ``key2`` must be supplied and will be the only key applied. """ # collect by absolute value of coefficient and key2 absc = defaultdict(list) if key1: for a in rv.args: c, a = a.as_coeff_Mul() if c < 0: c = -c a = -a # put the sign on `a` absc[(c, key2(a) if key2 else 1)].append(a) elif key2: for a in rv.args: absc[(S.One, key2(a))].append(a) else: raise ValueError('must have at least one key') args = [] hit = False for k in absc: v = absc[k] c, _ = k if len(v) > 1: e = Add(*v, evaluate=False) new = do(e) if new != e: e = new hit = True args.append(c*e) else: args.append(c*v[0]) if hit: rv = Add(*args) return rv fufuncs = ''' TR0 TR1 TR2 TR3 TR4 TR5 TR6 TR7 TR8 TR9 TR10 TR10i TR11 TR12 TR13 L TR2i TRmorrie TR12i TR14 TR15 TR16 TR111 TR22'''.split() FU = dict(list(zip(fufuncs, list(map(locals().get, fufuncs))))) def _roots(): global _ROOT2, _ROOT3, _invROOT3 _ROOT2, _ROOT3 = sqrt(2), sqrt(3) _invROOT3 = 1/_ROOT3 _ROOT2 = None def trig_split(a, b, two=False): """Return the gcd, s1, s2, a1, a2, bool where If two is False (default) then:: a + b = gcd*(s1*f(a1) + s2*f(a2)) where f = cos if bool else sin else: if bool, a + b was +/- cos(a1)*cos(a2) +/- sin(a1)*sin(a2) and equals n1*gcd*cos(a - b) if n1 == n2 else n1*gcd*cos(a + b) else a + b was +/- cos(a1)*sin(a2) +/- sin(a1)*cos(a2) and equals n1*gcd*sin(a + b) if n1 = n2 else n1*gcd*sin(b - a) Examples ======== >>> from sympy.simplify.fu import trig_split >>> from sympy.abc import x, y, z >>> from sympy import cos, sin, sqrt >>> trig_split(cos(x), cos(y)) (1, 1, 1, x, y, True) >>> trig_split(2*cos(x), -2*cos(y)) (2, 1, -1, x, y, True) >>> trig_split(cos(x)*sin(y), cos(y)*sin(y)) (sin(y), 1, 1, x, y, True) >>> trig_split(cos(x), -sqrt(3)*sin(x), two=True) (2, 1, -1, x, pi/6, False) >>> trig_split(cos(x), sin(x), two=True) (sqrt(2), 1, 1, x, pi/4, False) >>> trig_split(cos(x), -sin(x), two=True) (sqrt(2), 1, -1, x, pi/4, False) >>> trig_split(sqrt(2)*cos(x), -sqrt(6)*sin(x), two=True) (2*sqrt(2), 1, -1, x, pi/6, False) >>> trig_split(-sqrt(6)*cos(x), -sqrt(2)*sin(x), two=True) (-2*sqrt(2), 1, 1, x, pi/3, False) >>> trig_split(cos(x)/sqrt(6), sin(x)/sqrt(2), two=True) (sqrt(6)/3, 1, 1, x, pi/6, False) >>> trig_split(-sqrt(6)*cos(x)*sin(y), -sqrt(2)*sin(x)*sin(y), two=True) (-2*sqrt(2)*sin(y), 1, 1, x, pi/3, False) >>> trig_split(cos(x), sin(x)) >>> trig_split(cos(x), sin(z)) >>> trig_split(2*cos(x), -sin(x)) >>> trig_split(cos(x), -sqrt(3)*sin(x)) >>> trig_split(cos(x)*cos(y), sin(x)*sin(z)) >>> trig_split(cos(x)*cos(y), sin(x)*sin(y)) >>> trig_split(-sqrt(6)*cos(x), sqrt(2)*sin(x)*sin(y), two=True) """ global _ROOT2, _ROOT3, _invROOT3 if _ROOT2 is None: _roots() a, b = [Factors(i) for i in (a, b)] ua, ub = a.normal(b) gcd = a.gcd(b).as_expr() n1 = n2 = 1 if S.NegativeOne in ua.factors: ua = ua.quo(S.NegativeOne) n1 = -n1 elif S.NegativeOne in ub.factors: ub = ub.quo(S.NegativeOne) n2 = -n2 a, b = [i.as_expr() for i in (ua, ub)] def pow_cos_sin(a, two): """Return ``a`` as a tuple (r, c, s) such that ``a = (r or 1)*(c or 1)*(s or 1)``. Three arguments are returned (radical, c-factor, s-factor) as long as the conditions set by ``two`` are met; otherwise None is returned. If ``two`` is True there will be one or two non-None values in the tuple: c and s or c and r or s and r or s or c with c being a cosine function (if possible) else a sine, and s being a sine function (if possible) else oosine. If ``two`` is False then there will only be a c or s term in the tuple. ``two`` also require that either two cos and/or sin be present (with the condition that if the functions are the same the arguments are different or vice versa) or that a single cosine or a single sine be present with an optional radical. If the above conditions dictated by ``two`` are not met then None is returned. """ c = s = None co = S.One if a.is_Mul: co, a = a.as_coeff_Mul() if len(a.args) > 2 or not two: return None if a.is_Mul: args = list(a.args) else: args = [a] a = args.pop(0) if isinstance(a, cos): c = a elif isinstance(a, sin): s = a elif a.is_Pow and a.exp is S.Half: # autoeval doesn't allow -1/2 co *= a else: return None if args: b = args[0] if isinstance(b, cos): if c: s = b else: c = b elif isinstance(b, sin): if s: c = b else: s = b elif b.is_Pow and b.exp is S.Half: co *= b else: return None return co if co is not S.One else None, c, s elif isinstance(a, cos): c = a elif isinstance(a, sin): s = a if c is None and s is None: return co = co if co is not S.One else None return co, c, s # get the parts m = pow_cos_sin(a, two) if m is None: return coa, ca, sa = m m = pow_cos_sin(b, two) if m is None: return cob, cb, sb = m # check them if (not ca) and cb or ca and isinstance(ca, sin): coa, ca, sa, cob, cb, sb = cob, cb, sb, coa, ca, sa n1, n2 = n2, n1 if not two: # need cos(x) and cos(y) or sin(x) and sin(y) c = ca or sa s = cb or sb if not isinstance(c, s.func): return None return gcd, n1, n2, c.args[0], s.args[0], isinstance(c, cos) else: if not coa and not cob: if (ca and cb and sa and sb): if isinstance(ca, sa.func) is not isinstance(cb, sb.func): return args = {j.args for j in (ca, sa)} if not all(i.args in args for i in (cb, sb)): return return gcd, n1, n2, ca.args[0], sa.args[0], isinstance(ca, sa.func) if ca and sa or cb and sb or \ two and (ca is None and sa is None or cb is None and sb is None): return c = ca or sa s = cb or sb if c.args != s.args: return if not coa: coa = S.One if not cob: cob = S.One if coa is cob: gcd *= _ROOT2 return gcd, n1, n2, c.args[0], pi/4, False elif coa/cob == _ROOT3: gcd *= 2*cob return gcd, n1, n2, c.args[0], pi/3, False elif coa/cob == _invROOT3: gcd *= 2*coa return gcd, n1, n2, c.args[0], pi/6, False def as_f_sign_1(e): """If ``e`` is a sum that can be written as ``g*(a + s)`` where ``s`` is ``+/-1``, return ``g``, ``a``, and ``s`` where ``a`` does not have a leading negative coefficient. Examples ======== >>> from sympy.simplify.fu import as_f_sign_1 >>> from sympy.abc import x >>> as_f_sign_1(x + 1) (1, x, 1) >>> as_f_sign_1(x - 1) (1, x, -1) >>> as_f_sign_1(-x + 1) (-1, x, -1) >>> as_f_sign_1(-x - 1) (-1, x, 1) >>> as_f_sign_1(2*x + 2) (2, x, 1) """ if not e.is_Add or len(e.args) != 2: return # exact match a, b = e.args if a in (S.NegativeOne, S.One): g = S.One if b.is_Mul and b.args[0].is_Number and b.args[0] < 0: a, b = -a, -b g = -g return g, b, a # gcd match a, b = [Factors(i) for i in e.args] ua, ub = a.normal(b) gcd = a.gcd(b).as_expr() if S.NegativeOne in ua.factors: ua = ua.quo(S.NegativeOne) n1 = -1 n2 = 1 elif S.NegativeOne in ub.factors: ub = ub.quo(S.NegativeOne) n1 = 1 n2 = -1 else: n1 = n2 = 1 a, b = [i.as_expr() for i in (ua, ub)] if a is S.One: a, b = b, a n1, n2 = n2, n1 if n1 == -1: gcd = -gcd n2 = -n2 if b is S.One: return gcd, a, n2 def _osborne(e, d): """Replace all hyperbolic functions with trig functions using the Osborne rule. Notes ===== ``d`` is a dummy variable to prevent automatic evaluation of trigonometric/hyperbolic functions. References ========== .. [1] https://en.wikipedia.org/wiki/Hyperbolic_function """ def f(rv): if not isinstance(rv, HyperbolicFunction): return rv a = rv.args[0] a = a*d if not a.is_Add else Add._from_args([i*d for i in a.args]) if isinstance(rv, sinh): return I*sin(a) elif isinstance(rv, cosh): return cos(a) elif isinstance(rv, tanh): return I*tan(a) elif isinstance(rv, coth): return cot(a)/I elif isinstance(rv, sech): return sec(a) elif isinstance(rv, csch): return csc(a)/I else: raise NotImplementedError('unhandled %s' % rv.func) return bottom_up(e, f) def _osbornei(e, d): """Replace all trig functions with hyperbolic functions using the Osborne rule. Notes ===== ``d`` is a dummy variable to prevent automatic evaluation of trigonometric/hyperbolic functions. References ========== .. [1] https://en.wikipedia.org/wiki/Hyperbolic_function """ def f(rv): if not isinstance(rv, TrigonometricFunction): return rv const, x = rv.args[0].as_independent(d, as_Add=True) a = x.xreplace({d: S.One}) + const*I if isinstance(rv, sin): return sinh(a)/I elif isinstance(rv, cos): return cosh(a) elif isinstance(rv, tan): return tanh(a)/I elif isinstance(rv, cot): return coth(a)*I elif isinstance(rv, sec): return sech(a) elif isinstance(rv, csc): return csch(a)*I else: raise NotImplementedError('unhandled %s' % rv.func) return bottom_up(e, f) def hyper_as_trig(rv): """Return an expression containing hyperbolic functions in terms of trigonometric functions. Any trigonometric functions initially present are replaced with Dummy symbols and the function to undo the masking and the conversion back to hyperbolics is also returned. It should always be true that:: t, f = hyper_as_trig(expr) expr == f(t) Examples ======== >>> from sympy.simplify.fu import hyper_as_trig, fu >>> from sympy.abc import x >>> from sympy import cosh, sinh >>> eq = sinh(x)**2 + cosh(x)**2 >>> t, f = hyper_as_trig(eq) >>> f(fu(t)) cosh(2*x) References ========== .. [1] https://en.wikipedia.org/wiki/Hyperbolic_function """ from sympy.simplify.simplify import signsimp from sympy.simplify.radsimp import collect # mask off trig functions trigs = rv.atoms(TrigonometricFunction) reps = [(t, Dummy()) for t in trigs] masked = rv.xreplace(dict(reps)) # get inversion substitutions in place reps = [(v, k) for k, v in reps] d = Dummy() return _osborne(masked, d), lambda x: collect(signsimp( _osbornei(x, d).xreplace(dict(reps))), S.ImaginaryUnit) def sincos_to_sum(expr): """Convert products and powers of sin and cos to sums. Explanation =========== Applied power reduction TRpower first, then expands products, and converts products to sums with TR8. Examples ======== >>> from sympy.simplify.fu import sincos_to_sum >>> from sympy.abc import x >>> from sympy import cos, sin >>> sincos_to_sum(16*sin(x)**3*cos(2*x)**2) 7*sin(x) - 5*sin(3*x) + 3*sin(5*x) - sin(7*x) """ if not expr.has(cos, sin): return expr else: return TR8(expand_mul(TRpower(expr)))
192beedd92edc1db817dfc1dee8e2932f5cbf122e796a4e97999e93b3201f937
# References : # http://www.euclideanspace.com/maths/algebra/realNormedAlgebra/quaternions/ # https://en.wikipedia.org/wiki/Quaternion from sympy import S, Rational from sympy import re, im, conjugate, sign from sympy import sqrt, sin, cos, acos, exp, ln from sympy import trigsimp from sympy import integrate from sympy import Matrix from sympy import sympify from sympy.core.evalf import prec_to_dps from sympy.core.expr import Expr class Quaternion(Expr): """Provides basic quaternion operations. Quaternion objects can be instantiated as Quaternion(a, b, c, d) as in (a + b*i + c*j + d*k). Examples ======== >>> from sympy.algebras.quaternion import Quaternion >>> q = Quaternion(1, 2, 3, 4) >>> q 1 + 2*i + 3*j + 4*k Quaternions over complex fields can be defined as : >>> from sympy.algebras.quaternion import Quaternion >>> from sympy import symbols, I >>> x = symbols('x') >>> q1 = Quaternion(x, x**3, x, x**2, real_field = False) >>> q2 = Quaternion(3 + 4*I, 2 + 5*I, 0, 7 + 8*I, real_field = False) >>> q1 x + x**3*i + x*j + x**2*k >>> q2 (3 + 4*I) + (2 + 5*I)*i + 0*j + (7 + 8*I)*k """ _op_priority = 11.0 is_commutative = False def __new__(cls, a=0, b=0, c=0, d=0, real_field=True): a = sympify(a) b = sympify(b) c = sympify(c) d = sympify(d) if any(i.is_commutative is False for i in [a, b, c, d]): raise ValueError("arguments have to be commutative") else: obj = Expr.__new__(cls, a, b, c, d) obj._a = a obj._b = b obj._c = c obj._d = d obj._real_field = real_field return obj @property def a(self): return self._a @property def b(self): return self._b @property def c(self): return self._c @property def d(self): return self._d @property def real_field(self): return self._real_field @classmethod def from_axis_angle(cls, vector, angle): """Returns a rotation quaternion given the axis and the angle of rotation. Parameters ========== vector : tuple of three numbers The vector representation of the given axis. angle : number The angle by which axis is rotated (in radians). Returns ======= Quaternion The normalized rotation quaternion calculated from the given axis and the angle of rotation. Examples ======== >>> from sympy.algebras.quaternion import Quaternion >>> from sympy import pi, sqrt >>> q = Quaternion.from_axis_angle((sqrt(3)/3, sqrt(3)/3, sqrt(3)/3), 2*pi/3) >>> q 1/2 + 1/2*i + 1/2*j + 1/2*k """ (x, y, z) = vector norm = sqrt(x**2 + y**2 + z**2) (x, y, z) = (x / norm, y / norm, z / norm) s = sin(angle * S.Half) a = cos(angle * S.Half) b = x * s c = y * s d = z * s return cls(a, b, c, d).normalize() @classmethod def from_rotation_matrix(cls, M): """Returns the equivalent quaternion of a matrix. The quaternion will be normalized only if the matrix is special orthogonal (orthogonal and det(M) = 1). Parameters ========== M : Matrix Input matrix to be converted to equivalent quaternion. M must be special orthogonal (orthogonal and det(M) = 1) for the quaternion to be normalized. Returns ======= Quaternion The quaternion equivalent to given matrix. Examples ======== >>> from sympy.algebras.quaternion import Quaternion >>> from sympy import Matrix, symbols, cos, sin, trigsimp >>> x = symbols('x') >>> M = Matrix([[cos(x), -sin(x), 0], [sin(x), cos(x), 0], [0, 0, 1]]) >>> q = trigsimp(Quaternion.from_rotation_matrix(M)) >>> q sqrt(2)*sqrt(cos(x) + 1)/2 + 0*i + 0*j + sqrt(2 - 2*cos(x))*sign(sin(x))/2*k """ absQ = M.det()**Rational(1, 3) a = sqrt(absQ + M[0, 0] + M[1, 1] + M[2, 2]) / 2 b = sqrt(absQ + M[0, 0] - M[1, 1] - M[2, 2]) / 2 c = sqrt(absQ - M[0, 0] + M[1, 1] - M[2, 2]) / 2 d = sqrt(absQ - M[0, 0] - M[1, 1] + M[2, 2]) / 2 b = b * sign(M[2, 1] - M[1, 2]) c = c * sign(M[0, 2] - M[2, 0]) d = d * sign(M[1, 0] - M[0, 1]) return Quaternion(a, b, c, d) def __add__(self, other): return self.add(other) def __radd__(self, other): return self.add(other) def __sub__(self, other): return self.add(other*-1) def __mul__(self, other): return self._generic_mul(self, other) def __rmul__(self, other): return self._generic_mul(other, self) def __pow__(self, p): return self.pow(p) def __neg__(self): return Quaternion(-self._a, -self._b, -self._c, -self.d) def __truediv__(self, other): return self * sympify(other)**-1 def __rtruediv__(self, other): return sympify(other) * self**-1 def _eval_Integral(self, *args): return self.integrate(*args) def diff(self, *symbols, **kwargs): kwargs.setdefault('evaluate', True) return self.func(*[a.diff(*symbols, **kwargs) for a in self.args]) def add(self, other): """Adds quaternions. Parameters ========== other : Quaternion The quaternion to add to current (self) quaternion. Returns ======= Quaternion The resultant quaternion after adding self to other Examples ======== >>> from sympy.algebras.quaternion import Quaternion >>> from sympy import symbols >>> q1 = Quaternion(1, 2, 3, 4) >>> q2 = Quaternion(5, 6, 7, 8) >>> q1.add(q2) 6 + 8*i + 10*j + 12*k >>> q1 + 5 6 + 2*i + 3*j + 4*k >>> x = symbols('x', real = True) >>> q1.add(x) (x + 1) + 2*i + 3*j + 4*k Quaternions over complex fields : >>> from sympy.algebras.quaternion import Quaternion >>> from sympy import I >>> q3 = Quaternion(3 + 4*I, 2 + 5*I, 0, 7 + 8*I, real_field = False) >>> q3.add(2 + 3*I) (5 + 7*I) + (2 + 5*I)*i + 0*j + (7 + 8*I)*k """ q1 = self q2 = sympify(other) # If q2 is a number or a sympy expression instead of a quaternion if not isinstance(q2, Quaternion): if q1.real_field and q2.is_complex: return Quaternion(re(q2) + q1.a, im(q2) + q1.b, q1.c, q1.d) elif q2.is_commutative: return Quaternion(q1.a + q2, q1.b, q1.c, q1.d) else: raise ValueError("Only commutative expressions can be added with a Quaternion.") return Quaternion(q1.a + q2.a, q1.b + q2.b, q1.c + q2.c, q1.d + q2.d) def mul(self, other): """Multiplies quaternions. Parameters ========== other : Quaternion or symbol The quaternion to multiply to current (self) quaternion. Returns ======= Quaternion The resultant quaternion after multiplying self with other Examples ======== >>> from sympy.algebras.quaternion import Quaternion >>> from sympy import symbols >>> q1 = Quaternion(1, 2, 3, 4) >>> q2 = Quaternion(5, 6, 7, 8) >>> q1.mul(q2) (-60) + 12*i + 30*j + 24*k >>> q1.mul(2) 2 + 4*i + 6*j + 8*k >>> x = symbols('x', real = True) >>> q1.mul(x) x + 2*x*i + 3*x*j + 4*x*k Quaternions over complex fields : >>> from sympy.algebras.quaternion import Quaternion >>> from sympy import I >>> q3 = Quaternion(3 + 4*I, 2 + 5*I, 0, 7 + 8*I, real_field = False) >>> q3.mul(2 + 3*I) (2 + 3*I)*(3 + 4*I) + (2 + 3*I)*(2 + 5*I)*i + 0*j + (2 + 3*I)*(7 + 8*I)*k """ return self._generic_mul(self, other) @staticmethod def _generic_mul(q1, q2): """Generic multiplication. Parameters ========== q1 : Quaternion or symbol q2 : Quaternion or symbol It's important to note that if neither q1 nor q2 is a Quaternion, this function simply returns q1 * q2. Returns ======= Quaternion The resultant quaternion after multiplying q1 and q2 Examples ======== >>> from sympy.algebras.quaternion import Quaternion >>> from sympy import Symbol >>> q1 = Quaternion(1, 2, 3, 4) >>> q2 = Quaternion(5, 6, 7, 8) >>> Quaternion._generic_mul(q1, q2) (-60) + 12*i + 30*j + 24*k >>> Quaternion._generic_mul(q1, 2) 2 + 4*i + 6*j + 8*k >>> x = Symbol('x', real = True) >>> Quaternion._generic_mul(q1, x) x + 2*x*i + 3*x*j + 4*x*k Quaternions over complex fields : >>> from sympy.algebras.quaternion import Quaternion >>> from sympy import I >>> q3 = Quaternion(3 + 4*I, 2 + 5*I, 0, 7 + 8*I, real_field = False) >>> Quaternion._generic_mul(q3, 2 + 3*I) (2 + 3*I)*(3 + 4*I) + (2 + 3*I)*(2 + 5*I)*i + 0*j + (2 + 3*I)*(7 + 8*I)*k """ q1 = sympify(q1) q2 = sympify(q2) # None is a Quaternion: if not isinstance(q1, Quaternion) and not isinstance(q2, Quaternion): return q1 * q2 # If q1 is a number or a sympy expression instead of a quaternion if not isinstance(q1, Quaternion): if q2.real_field and q1.is_complex: return Quaternion(re(q1), im(q1), 0, 0) * q2 elif q1.is_commutative: return Quaternion(q1 * q2.a, q1 * q2.b, q1 * q2.c, q1 * q2.d) else: raise ValueError("Only commutative expressions can be multiplied with a Quaternion.") # If q2 is a number or a sympy expression instead of a quaternion if not isinstance(q2, Quaternion): if q1.real_field and q2.is_complex: return q1 * Quaternion(re(q2), im(q2), 0, 0) elif q2.is_commutative: return Quaternion(q2 * q1.a, q2 * q1.b, q2 * q1.c, q2 * q1.d) else: raise ValueError("Only commutative expressions can be multiplied with a Quaternion.") return Quaternion(-q1.b*q2.b - q1.c*q2.c - q1.d*q2.d + q1.a*q2.a, q1.b*q2.a + q1.c*q2.d - q1.d*q2.c + q1.a*q2.b, -q1.b*q2.d + q1.c*q2.a + q1.d*q2.b + q1.a*q2.c, q1.b*q2.c - q1.c*q2.b + q1.d*q2.a + q1.a * q2.d) def _eval_conjugate(self): """Returns the conjugate of the quaternion.""" q = self return Quaternion(q.a, -q.b, -q.c, -q.d) def norm(self): """Returns the norm of the quaternion.""" q = self # trigsimp is used to simplify sin(x)^2 + cos(x)^2 (these terms # arise when from_axis_angle is used). return sqrt(trigsimp(q.a**2 + q.b**2 + q.c**2 + q.d**2)) def normalize(self): """Returns the normalized form of the quaternion.""" q = self return q * (1/q.norm()) def inverse(self): """Returns the inverse of the quaternion.""" q = self if not q.norm(): raise ValueError("Cannot compute inverse for a quaternion with zero norm") return conjugate(q) * (1/q.norm()**2) def pow(self, p): """Finds the pth power of the quaternion. Parameters ========== p : int Power to be applied on quaternion. Returns ======= Quaternion Returns the p-th power of the current quaternion. Returns the inverse if p = -1. Examples ======== >>> from sympy.algebras.quaternion import Quaternion >>> q = Quaternion(1, 2, 3, 4) >>> q.pow(4) 668 + (-224)*i + (-336)*j + (-448)*k """ p = sympify(p) q = self if p == -1: return q.inverse() res = 1 if not p.is_Integer: return NotImplemented if p < 0: q, p = q.inverse(), -p while p > 0: if p % 2 == 1: res = q * res p = p//2 q = q * q return res def exp(self): """Returns the exponential of q (e^q). Returns ======= Quaternion Exponential of q (e^q). Examples ======== >>> from sympy.algebras.quaternion import Quaternion >>> q = Quaternion(1, 2, 3, 4) >>> q.exp() E*cos(sqrt(29)) + 2*sqrt(29)*E*sin(sqrt(29))/29*i + 3*sqrt(29)*E*sin(sqrt(29))/29*j + 4*sqrt(29)*E*sin(sqrt(29))/29*k """ # exp(q) = e^a(cos||v|| + v/||v||*sin||v||) q = self vector_norm = sqrt(q.b**2 + q.c**2 + q.d**2) a = exp(q.a) * cos(vector_norm) b = exp(q.a) * sin(vector_norm) * q.b / vector_norm c = exp(q.a) * sin(vector_norm) * q.c / vector_norm d = exp(q.a) * sin(vector_norm) * q.d / vector_norm return Quaternion(a, b, c, d) def _ln(self): """Returns the natural logarithm of the quaternion (_ln(q)). Examples ======== >>> from sympy.algebras.quaternion import Quaternion >>> q = Quaternion(1, 2, 3, 4) >>> q._ln() log(sqrt(30)) + 2*sqrt(29)*acos(sqrt(30)/30)/29*i + 3*sqrt(29)*acos(sqrt(30)/30)/29*j + 4*sqrt(29)*acos(sqrt(30)/30)/29*k """ # _ln(q) = _ln||q|| + v/||v||*arccos(a/||q||) q = self vector_norm = sqrt(q.b**2 + q.c**2 + q.d**2) q_norm = q.norm() a = ln(q_norm) b = q.b * acos(q.a / q_norm) / vector_norm c = q.c * acos(q.a / q_norm) / vector_norm d = q.d * acos(q.a / q_norm) / vector_norm return Quaternion(a, b, c, d) def _eval_evalf(self, prec): """Returns the floating point approximations (decimal numbers) of the quaternion. Returns ======= Quaternion Floating point approximations of quaternion(self) Examples ======== >>> from sympy.algebras.quaternion import Quaternion >>> from sympy import sqrt >>> q = Quaternion(1/sqrt(1), 1/sqrt(2), 1/sqrt(3), 1/sqrt(4)) >>> q.evalf() 1.00000000000000 + 0.707106781186547*i + 0.577350269189626*j + 0.500000000000000*k """ return Quaternion(*[arg.evalf(n=prec_to_dps(prec)) for arg in self.args]) def pow_cos_sin(self, p): """Computes the pth power in the cos-sin form. Parameters ========== p : int Power to be applied on quaternion. Returns ======= Quaternion The p-th power in the cos-sin form. Examples ======== >>> from sympy.algebras.quaternion import Quaternion >>> q = Quaternion(1, 2, 3, 4) >>> q.pow_cos_sin(4) 900*cos(4*acos(sqrt(30)/30)) + 1800*sqrt(29)*sin(4*acos(sqrt(30)/30))/29*i + 2700*sqrt(29)*sin(4*acos(sqrt(30)/30))/29*j + 3600*sqrt(29)*sin(4*acos(sqrt(30)/30))/29*k """ # q = ||q||*(cos(a) + u*sin(a)) # q^p = ||q||^p * (cos(p*a) + u*sin(p*a)) q = self (v, angle) = q.to_axis_angle() q2 = Quaternion.from_axis_angle(v, p * angle) return q2 * (q.norm()**p) def integrate(self, *args): """Computes integration of quaternion. Returns ======= Quaternion Integration of the quaternion(self) with the given variable. Examples ======== Indefinite Integral of quaternion : >>> from sympy.algebras.quaternion import Quaternion >>> from sympy.abc import x >>> q = Quaternion(1, 2, 3, 4) >>> q.integrate(x) x + 2*x*i + 3*x*j + 4*x*k Definite integral of quaternion : >>> from sympy.algebras.quaternion import Quaternion >>> from sympy.abc import x >>> q = Quaternion(1, 2, 3, 4) >>> q.integrate((x, 1, 5)) 4 + 8*i + 12*j + 16*k """ # TODO: is this expression correct? return Quaternion(integrate(self.a, *args), integrate(self.b, *args), integrate(self.c, *args), integrate(self.d, *args)) @staticmethod def rotate_point(pin, r): """Returns the coordinates of the point pin(a 3 tuple) after rotation. Parameters ========== pin : tuple A 3-element tuple of coordinates of a point which needs to be rotated. r : Quaternion or tuple Axis and angle of rotation. It's important to note that when r is a tuple, it must be of the form (axis, angle) Returns ======= tuple The coordinates of the point after rotation. Examples ======== >>> from sympy.algebras.quaternion import Quaternion >>> from sympy import symbols, trigsimp, cos, sin >>> x = symbols('x') >>> q = Quaternion(cos(x/2), 0, 0, sin(x/2)) >>> trigsimp(Quaternion.rotate_point((1, 1, 1), q)) (sqrt(2)*cos(x + pi/4), sqrt(2)*sin(x + pi/4), 1) >>> (axis, angle) = q.to_axis_angle() >>> trigsimp(Quaternion.rotate_point((1, 1, 1), (axis, angle))) (sqrt(2)*cos(x + pi/4), sqrt(2)*sin(x + pi/4), 1) """ if isinstance(r, tuple): # if r is of the form (vector, angle) q = Quaternion.from_axis_angle(r[0], r[1]) else: # if r is a quaternion q = r.normalize() pout = q * Quaternion(0, pin[0], pin[1], pin[2]) * conjugate(q) return (pout.b, pout.c, pout.d) def to_axis_angle(self): """Returns the axis and angle of rotation of a quaternion Returns ======= tuple Tuple of (axis, angle) Examples ======== >>> from sympy.algebras.quaternion import Quaternion >>> q = Quaternion(1, 1, 1, 1) >>> (axis, angle) = q.to_axis_angle() >>> axis (sqrt(3)/3, sqrt(3)/3, sqrt(3)/3) >>> angle 2*pi/3 """ q = self if q.a.is_negative: q = q * -1 q = q.normalize() angle = trigsimp(2 * acos(q.a)) # Since quaternion is normalised, q.a is less than 1. s = sqrt(1 - q.a*q.a) x = trigsimp(q.b / s) y = trigsimp(q.c / s) z = trigsimp(q.d / s) v = (x, y, z) t = (v, angle) return t def to_rotation_matrix(self, v=None): """Returns the equivalent rotation transformation matrix of the quaternion which represents rotation about the origin if v is not passed. Parameters ========== v : tuple or None Default value: None Returns ======= tuple Returns the equivalent rotation transformation matrix of the quaternion which represents rotation about the origin if v is not passed. Examples ======== >>> from sympy.algebras.quaternion import Quaternion >>> from sympy import symbols, trigsimp, cos, sin >>> x = symbols('x') >>> q = Quaternion(cos(x/2), 0, 0, sin(x/2)) >>> trigsimp(q.to_rotation_matrix()) Matrix([ [cos(x), -sin(x), 0], [sin(x), cos(x), 0], [ 0, 0, 1]]) Generates a 4x4 transformation matrix (used for rotation about a point other than the origin) if the point(v) is passed as an argument. Examples ======== >>> from sympy.algebras.quaternion import Quaternion >>> from sympy import symbols, trigsimp, cos, sin >>> x = symbols('x') >>> q = Quaternion(cos(x/2), 0, 0, sin(x/2)) >>> trigsimp(q.to_rotation_matrix((1, 1, 1))) Matrix([ [cos(x), -sin(x), 0, sin(x) - cos(x) + 1], [sin(x), cos(x), 0, -sin(x) - cos(x) + 1], [ 0, 0, 1, 0], [ 0, 0, 0, 1]]) """ q = self s = q.norm()**-2 m00 = 1 - 2*s*(q.c**2 + q.d**2) m01 = 2*s*(q.b*q.c - q.d*q.a) m02 = 2*s*(q.b*q.d + q.c*q.a) m10 = 2*s*(q.b*q.c + q.d*q.a) m11 = 1 - 2*s*(q.b**2 + q.d**2) m12 = 2*s*(q.c*q.d - q.b*q.a) m20 = 2*s*(q.b*q.d - q.c*q.a) m21 = 2*s*(q.c*q.d + q.b*q.a) m22 = 1 - 2*s*(q.b**2 + q.c**2) if not v: return Matrix([[m00, m01, m02], [m10, m11, m12], [m20, m21, m22]]) else: (x, y, z) = v m03 = x - x*m00 - y*m01 - z*m02 m13 = y - x*m10 - y*m11 - z*m12 m23 = z - x*m20 - y*m21 - z*m22 m30 = m31 = m32 = 0 m33 = 1 return Matrix([[m00, m01, m02, m03], [m10, m11, m12, m13], [m20, m21, m22, m23], [m30, m31, m32, m33]])