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"""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, | |
all_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.combinatorics.galois import S4TransitiveSubgroups | |
from sympy.core.add import Add | |
from sympy.core.basic import _aresame | |
from sympy.core.containers import Tuple | |
from sympy.core.expr import Expr | |
from sympy.core.function import (Derivative, diff, expand) | |
from sympy.core.mul import _keep_coeff, Mul | |
from sympy.core.numbers import (Float, I, Integer, Rational, oo, pi) | |
from sympy.core.power import Pow | |
from sympy.core.relational import Eq | |
from sympy.core.singleton import S | |
from sympy.core.symbol import Symbol | |
from sympy.functions.elementary.complexes import (im, re) | |
from sympy.functions.elementary.exponential import exp | |
from sympy.functions.elementary.hyperbolic import tanh | |
from sympy.functions.elementary.miscellaneous import sqrt | |
from sympy.functions.elementary.piecewise import Piecewise | |
from sympy.functions.elementary.trigonometric import sin | |
from sympy.matrices.dense import Matrix | |
from sympy.matrices.expressions.matexpr import MatrixSymbol | |
from sympy.polys.rootoftools import rootof | |
from sympy.simplify.simplify import signsimp | |
from sympy.utilities.iterables import iterable | |
from sympy.utilities.exceptions import SymPyDeprecationWarning | |
from sympy.testing.pytest import raises, warns_deprecated_sympy, warns | |
from sympy.abc import a, b, c, d, p, q, t, w, x, y, z | |
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([ZZ(1), ZZ(7)], ZZ) | |
assert Poly.from_poly(f, domain=QQ).rep == DMP([QQ(1), QQ(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([ZZ(1), ZZ(7)], ZZ) | |
assert Poly.from_poly(f, gens=x, domain=QQ).rep == DMP([QQ(1), QQ(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([ZZ(1), ZZ(-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([ZZ(1), ZZ(-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([ZZ(1), ZZ(5)], ZZ) | |
assert Poly.from_expr(y + 5).rep == DMP([ZZ(1), ZZ(5)], ZZ) | |
assert Poly.from_expr(x + 5, x).rep == DMP([ZZ(1), ZZ(5)], ZZ) | |
assert Poly.from_expr(y + 5, y).rep == DMP([ZZ(1), ZZ(5)], ZZ) | |
assert Poly.from_expr(x + 5, domain=ZZ).rep == DMP([ZZ(1), ZZ(5)], ZZ) | |
assert Poly.from_expr(y + 5, domain=ZZ).rep == DMP([ZZ(1), ZZ(5)], ZZ) | |
assert Poly.from_expr(x + 5, x, domain=ZZ).rep == DMP([ZZ(1), ZZ(5)], ZZ) | |
assert Poly.from_expr(y + 5, y, domain=ZZ).rep == DMP([ZZ(1), ZZ(5)], ZZ) | |
assert Poly.from_expr(x + 5, x, y, domain=ZZ).rep == DMP([[ZZ(1)], [ZZ(5)]], ZZ) | |
assert Poly.from_expr(y + 5, x, y, domain=ZZ).rep == DMP([[ZZ(1), ZZ(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([ZZ(1), ZZ(1)]), y, domain=dom).rep == DMP([dom([ZZ(1), ZZ(1)])], dom) | |
dom = dom.get_field() | |
assert Poly(dom([ZZ(1), ZZ(1)]), y, domain=dom).rep == DMP([dom([ZZ(1), ZZ(1)])], dom) | |
dom = QQ.old_poly_ring(x) | |
assert Poly(dom([QQ(1), QQ(1)]), y, domain=dom).rep == DMP([dom([QQ(1), QQ(1)])], dom) | |
dom = dom.get_field() | |
assert Poly(dom([QQ(1), QQ(1)]), y, domain=dom).rep == DMP([dom([QQ(1), QQ(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)) | |
assert Poly('x-x') == Poly(0, x) | |
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) | |
assert Poly(x, x, modulus=3)._unify(Poly(y, y, modulus=3))[2:] == ( | |
DMP([[F3(1)], []], F3), DMP([[F3(1), F3(0)]], F3)) | |
raises(UnificationFailed, lambda: Poly(x, x, modulus=3)._unify(Poly(y, y, modulus=5))) | |
raises(UnificationFailed, lambda: Poly(y, x, y)._unify(Poly(x, x, modulus=3))) | |
raises(UnificationFailed, lambda: Poly(x, x, modulus=3)._unify(Poly(y, x, y))) | |
assert Poly(x + 1, x)._unify(Poly(x + 2, x))[2:] ==\ | |
(DMP([ZZ(1), ZZ(1)], ZZ), DMP([ZZ(1), ZZ(2)], ZZ)) | |
assert Poly(x + 1, x, domain='QQ')._unify(Poly(x + 2, x))[2:] ==\ | |
(DMP([QQ(1), QQ(1)], QQ), DMP([QQ(1), QQ(2)], QQ)) | |
assert Poly(x + 1, x)._unify(Poly(x + 2, x, domain='QQ'))[2:] ==\ | |
(DMP([QQ(1), QQ(1)], QQ), DMP([QQ(1), QQ(2)], QQ)) | |
assert Poly(x + 1, x)._unify(Poly(x + 2, x, y))[2:] ==\ | |
(DMP([[ZZ(1)], [ZZ(1)]], ZZ), DMP([[ZZ(1)], [ZZ(2)]], ZZ)) | |
assert Poly(x + 1, x, domain='QQ')._unify(Poly(x + 2, x, y))[2:] ==\ | |
(DMP([[QQ(1)], [QQ(1)]], QQ), DMP([[QQ(1)], [QQ(2)]], QQ)) | |
assert Poly(x + 1, x)._unify(Poly(x + 2, x, y, domain='QQ'))[2:] ==\ | |
(DMP([[QQ(1)], [QQ(1)]], QQ), DMP([[QQ(1)], [QQ(2)]], QQ)) | |
assert Poly(x + 1, x, y)._unify(Poly(x + 2, x))[2:] ==\ | |
(DMP([[ZZ(1)], [ZZ(1)]], ZZ), DMP([[ZZ(1)], [ZZ(2)]], ZZ)) | |
assert Poly(x + 1, x, y, domain='QQ')._unify(Poly(x + 2, x))[2:] ==\ | |
(DMP([[QQ(1)], [QQ(1)]], QQ), DMP([[QQ(1)], [QQ(2)]], QQ)) | |
assert Poly(x + 1, x, y)._unify(Poly(x + 2, x, domain='QQ'))[2:] ==\ | |
(DMP([[QQ(1)], [QQ(1)]], QQ), DMP([[QQ(1)], [QQ(2)]], QQ)) | |
assert Poly(x + 1, x, y)._unify(Poly(x + 2, x, y))[2:] ==\ | |
(DMP([[ZZ(1)], [ZZ(1)]], ZZ), DMP([[ZZ(1)], [ZZ(2)]], ZZ)) | |
assert Poly(x + 1, x, y, domain='QQ')._unify(Poly(x + 2, x, y))[2:] ==\ | |
(DMP([[QQ(1)], [QQ(1)]], QQ), DMP([[QQ(1)], [QQ(2)]], QQ)) | |
assert Poly(x + 1, x, y)._unify(Poly(x + 2, x, y, domain='QQ'))[2:] ==\ | |
(DMP([[QQ(1)], [QQ(1)]], QQ), DMP([[QQ(1)], [QQ(2)]], QQ)) | |
assert Poly(x + 1, x)._unify(Poly(x + 2, y, x))[2:] ==\ | |
(DMP([[ZZ(1), ZZ(1)]], ZZ), DMP([[ZZ(1), ZZ(2)]], ZZ)) | |
assert Poly(x + 1, x, domain='QQ')._unify(Poly(x + 2, y, x))[2:] ==\ | |
(DMP([[QQ(1), QQ(1)]], QQ), DMP([[QQ(1), QQ(2)]], QQ)) | |
assert Poly(x + 1, x)._unify(Poly(x + 2, y, x, domain='QQ'))[2:] ==\ | |
(DMP([[QQ(1), QQ(1)]], QQ), DMP([[QQ(1), QQ(2)]], QQ)) | |
assert Poly(x + 1, y, x)._unify(Poly(x + 2, x))[2:] ==\ | |
(DMP([[ZZ(1), ZZ(1)]], ZZ), DMP([[ZZ(1), ZZ(2)]], ZZ)) | |
assert Poly(x + 1, y, x, domain='QQ')._unify(Poly(x + 2, x))[2:] ==\ | |
(DMP([[QQ(1), QQ(1)]], QQ), DMP([[QQ(1), QQ(2)]], QQ)) | |
assert Poly(x + 1, y, x)._unify(Poly(x + 2, x, domain='QQ'))[2:] ==\ | |
(DMP([[QQ(1), QQ(1)]], QQ), DMP([[QQ(1), QQ(2)]], QQ)) | |
assert Poly(x + 1, x, y)._unify(Poly(x + 2, y, x))[2:] ==\ | |
(DMP([[ZZ(1)], [ZZ(1)]], ZZ), DMP([[ZZ(1)], [ZZ(2)]], ZZ)) | |
assert Poly(x + 1, x, y, domain='QQ')._unify(Poly(x + 2, y, x))[2:] ==\ | |
(DMP([[QQ(1)], [QQ(1)]], QQ), DMP([[QQ(1)], [QQ(2)]], QQ)) | |
assert Poly(x + 1, x, y)._unify(Poly(x + 2, y, x, domain='QQ'))[2:] ==\ | |
(DMP([[QQ(1)], [QQ(1)]], QQ), DMP([[QQ(1)], [QQ(2)]], QQ)) | |
assert Poly(x + 1, y, x)._unify(Poly(x + 2, x, y))[2:] ==\ | |
(DMP([[ZZ(1), ZZ(1)]], ZZ), DMP([[ZZ(1), ZZ(2)]], ZZ)) | |
assert Poly(x + 1, y, x, domain='QQ')._unify(Poly(x + 2, x, y))[2:] ==\ | |
(DMP([[QQ(1), QQ(1)]], QQ), DMP([[QQ(1), QQ(2)]], QQ)) | |
assert Poly(x + 1, y, x)._unify(Poly(x + 2, x, y, domain='QQ'))[2:] ==\ | |
(DMP([[QQ(1), QQ(1)]], QQ), DMP([[QQ(1), QQ(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) | |
g = Poly(x**3 + 1) | |
assert g.slice(0, 3) == Poly(1, 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')) | |
f = 5*x**2 + 10*x + 3 | |
g = 2*x + 2 | |
assert div(f, g, domain=ZZ) == (0, f) | |
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)) | |
f = Poly(-1, x) | |
g = Poly(1, x) | |
assert lcm(f, g) == Poly(1, x) | |
f = Poly(0, x) | |
g = Poly([1, 1], x) | |
for i in (f, g): | |
assert lcm(i, 0) == 0 | |
assert lcm(0, i) == 0 | |
assert lcm(i, f) == 0 | |
assert lcm(f, i) == 0 | |
f = 4*x**2 + x + 2 | |
pfz = Poly(f, domain=ZZ) | |
pfq = Poly(f, domain=QQ) | |
assert pfz.gcd(pfz) == pfz | |
assert pfz.lcm(pfz) == pfz | |
assert pfq.gcd(pfq) == pfq.monic() | |
assert pfq.lcm(pfq) == pfq.monic() | |
assert gcd(f, f) == f | |
assert lcm(f, f) == f | |
assert gcd(f, f, domain=QQ) == monic(f) | |
assert lcm(f, f, domain=QQ) == monic(f) | |
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_shift_list(): | |
assert Poly(x*y, [x,y]).shift_list([1,2]) == Poly((x+1)*(y+2), [x,y]) | |
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)]) | |
# https://github.com/sympy/sympy/issues/26497 | |
assert sqf(expand(((y - 2)**2 * (y + 2) * (x + 1)))) == \ | |
(y - 2)**2 * expand((y + 2) * (x + 1)) | |
assert sqf(expand(((y - 2)**2 * (y + 2) * (z + 1)))) == \ | |
(y - 2)**2 * expand((y + 2) * (z + 1)) | |
assert sqf(expand(((y - I)**2 * (y + I) * (x + 1)))) == \ | |
(y - I)**2 * expand((y + I) * (x + 1)) | |
assert sqf(expand(((y - I)**2 * (y + I) * (z + 1)))) == \ | |
(y - I)**2 * expand((y + I) * (z + 1)) | |
# Check that factors are combined and sorted. | |
p = (x - 2)**2*(x - 1)*(x + y)**2*(y - 2)**2*(y - 1) | |
assert Poly(p).sqf_list() == (1, [ | |
(Poly(x*y - x - y + 1), 1), | |
(Poly(x**2*y - 2*x**2 + x*y**2 - 4*x*y + 4*x - 2*y**2 + 4*y), 2) | |
]) | |
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) | |
assert factor_list(x**3 - x*y**2, t, w, x) == ( | |
1, [(x, 1), (x - y, 1), (x + y, 1)]) | |
# https://github.com/sympy/sympy/issues/24952 | |
s2, s2p, s2n = sqrt(2), 1 + sqrt(2), 1 - sqrt(2) | |
pip, pin = 1 + pi, 1 - pi | |
assert factor_list(s2p*s2n) == (-1, [(-s2n, 1), (s2p, 1)]) | |
assert factor_list(pip*pin) == (-1, [(-pin, 1), (pip, 1)]) | |
# Not sure about this one. Maybe coeff should be 1 or -1? | |
assert factor_list(s2*s2n) == (-s2, [(-s2n, 1)]) | |
assert factor_list(pi*pin) == (-1, [(-pin, 1), (pi, 1)]) | |
assert factor_list(s2p*s2n, x) == (s2p*s2n, []) | |
assert factor_list(pip*pin, x) == (pip*pin, []) | |
assert factor_list(s2*s2n, x) == (s2*s2n, []) | |
assert factor_list(pi*pin, x) == (pi*pin, []) | |
assert factor_list((x - sqrt(2)*pi)*(x + sqrt(2)*pi), x) == ( | |
1, [(x - sqrt(2)*pi, 1), (x + sqrt(2)*pi, 1)]) | |
# https://github.com/sympy/sympy/issues/26497 | |
p = ((y - I)**2 * (y + I) * (x + 1)) | |
assert factor(expand(p)) == p | |
p = ((x - I)**2 * (x + I) * (y + 1)) | |
assert factor(expand(p)) == p | |
p = (y + 1)**2*(y + sqrt(2))**2*(x**2 + x + 2 + 3*sqrt(2))**2 | |
assert factor(expand(p), extension=True) == p | |
e = ( | |
-x**2*y**4/(y**2 + 1) + 2*I*x**2*y**3/(y**2 + 1) + 2*I*x**2*y/(y**2 + 1) + | |
x**2/(y**2 + 1) - 2*x*y**4/(y**2 + 1) + 4*I*x*y**3/(y**2 + 1) + | |
4*I*x*y/(y**2 + 1) + 2*x/(y**2 + 1) - y**4 - y**4/(y**2 + 1) + 2*I*y**3 | |
+ 2*I*y**3/(y**2 + 1) + 2*I*y + 2*I*y/(y**2 + 1) + 1 + 1/(y**2 + 1) | |
) | |
assert factor(e) == -(y - I)**3*(y + I)*(x**2 + 2*x + y**2 + 2)/(y**2 + 1) | |
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*40/7, 0), | |
(Rational(-40, 7), I*40/7), | |
(I*Rational(-40, 7), Rational(40, 7)), | |
(0, Rational(40, 7) + I*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)] | |
assert real_roots(x**2 - 2, radicals=False) == [ | |
rootof(x**2 - 2, 0, radicals=False), | |
rootof(x**2 - 2, 1, radicals=False), | |
] | |
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 | |
froots = [Rational(-1, 2), 2, 2] | |
assert all_roots(f) == Poly(f).all_roots() == froots | |
g = x**3 + x + 1 | |
groots = [rootof(g, 0), rootof(g, 1), rootof(g, 2)] | |
assert all_roots(g) == Poly(g).all_roots() == groots | |
assert all_roots(x**2 - 2) == [-sqrt(2), sqrt(2)] | |
assert all_roots(x**2 - 2, multiple=False) == [(-sqrt(2), 1), (sqrt(2), 1)] | |
assert all_roots(x**2 - 2, radicals=False) == [ | |
rootof(x**2 - 2, 0, radicals=False), | |
rootof(x**2 - 2, 1, radicals=False), | |
] | |
p = x**5 - x - 1 | |
assert all_roots(p) == [ | |
rootof(p, 0), rootof(p, 1), rootof(p, 2), rootof(p, 3), rootof(p, 4) | |
] | |
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]) == Float(-0.5, 5) | |
assert im(roots[1]).epsilon_eq(-0.86602, eps) is S.true | |
assert re(roots[2]) == Float(-0.5, 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]) == Float(-0.5, 5) | |
assert im(roots[1]).epsilon_eq(-0.86602, eps) is S.false | |
assert re(roots[2]) == Float(-0.5, 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]') | |
assert str(Poly(1e-15*x**2 -1).nroots()) == ('[-31622776.6016838, 31622776.6016838]') | |
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_same_root(): | |
f = Poly(x**4 + x**3 + x**2 + x + 1) | |
eq = f.same_root | |
r0 = exp(2 * I * pi / 5) | |
assert [i for i, r in enumerate(f.all_roots()) if eq(r, r0)] == [3] | |
raises(PolynomialError, | |
lambda: Poly(x + 1, domain=QQ).same_root(0, 0)) | |
raises(DomainError, | |
lambda: Poly(x**2 + 1, domain=FF(7)).same_root(0, 0)) | |
raises(DomainError, | |
lambda: Poly(x ** 2 + 1, domain=ZZ_I).same_root(0, 0)) | |
raises(DomainError, | |
lambda: Poly(y * x**2 + 1, domain=ZZ[y]).same_root(0, 0)) | |
raises(MultivariatePolynomialError, | |
lambda: Poly(x * y + 1, domain=ZZ).same_root(0, 0)) | |
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(x/3 + 1, x) | |
g = Poly(x/7 + 1, x) | |
assert f.cancel(g) == (S(7)/3, | |
Poly(x + 3, x, domain=QQ), | |
Poly(x + 7, x, domain=QQ)) | |
assert f.cancel(g, include=True) == ( | |
Poly(7*x + 21, x, domain=QQ), | |
Poly(3*x + 21, x, domain=QQ)) | |
pairs = [ | |
(1 + x, 1 + x, 1, 1, 1), | |
(1 + x, 1 - x, -1, -1-x, -1+x), | |
(1 - x, 1 + x, -1, 1-x, 1+x), | |
(1 - x, 1 - x, 1, 1, 1), | |
] | |
for f, g, coeff, p, q in pairs: | |
assert cancel((f, g)) == (1, p, q) | |
pf = Poly(f, x) | |
pg = Poly(g, x) | |
pp = Poly(p, x) | |
pq = Poly(q, x) | |
assert pf.cancel(pg) == (coeff, coeff*pp, pq) | |
assert pf.rep.cancel(pg.rep) == (pp.rep, pq.rep) | |
assert pf.rep.cancel(pg.rep, include=True) == (pp.rep, pq.rep) | |
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 4077 | |
q = S('''(2*1*(x - 1/x)/(x*(2*x - (-x + 1/x)/(x**2*(x - 1/x)**2) - 1/(x**2*(x - | |
1/x)) - 2/x)) - 2*1*((x - 1/x)/((x*(x - 1/x)**2)) - 1/(x*(x - | |
1/x)))*((-x + 1/x)*((x - 1/x)/((x*(x - 1/x)**2)) - 1/(x*(x - | |
1/x)))/(2*x - (-x + 1/x)/(x**2*(x - 1/x)**2) - 1/(x**2*(x - 1/x)) - | |
2/x) + 1)*((x - 1/x)/((x - 1/x)**2) - ((x - 1/x)/((x*(x - 1/x)**2)) - | |
1/(x*(x - 1/x)))**2/(2*x - (-x + 1/x)/(x**2*(x - 1/x)**2) - 1/(x**2*(x | |
- 1/x)) - 2/x) - 1/(x - 1/x))*(2*x - (-x + 1/x)/(x**2*(x - 1/x)**2) - | |
1/(x**2*(x - 1/x)) - 2/x)/x - 1/x)*(((-x + 1/x)/((x*(x - 1/x)**2)) + | |
1/(x*(x - 1/x)))*((-(x - 1/x)/(x*(x - 1/x)) - 1/x)*((x - 1/x)/((x*(x - | |
1/x)**2)) - 1/(x*(x - 1/x)))/(2*x - (-x + 1/x)/(x**2*(x - 1/x)**2) - | |
1/(x**2*(x - 1/x)) - 2/x) - 1 + (x - 1/x)/(x - 1/x))/((x*((x - | |
1/x)/((x - 1/x)**2) - ((x - 1/x)/((x*(x - 1/x)**2)) - 1/(x*(x - | |
1/x)))**2/(2*x - (-x + 1/x)/(x**2*(x - 1/x)**2) - 1/(x**2*(x - 1/x)) - | |
2/x) - 1/(x - 1/x))*(2*x - (-x + 1/x)/(x**2*(x - 1/x)**2) - 1/(x**2*(x | |
- 1/x)) - 2/x))) + ((x - 1/x)/((x*(x - 1/x))) + 1/x)/((x*(2*x - (-x + | |
1/x)/(x**2*(x - 1/x)**2) - 1/(x**2*(x - 1/x)) - 2/x))) + 1/x)/(2*x + | |
2*((x - 1/x)/((x*(x - 1/x)**2)) - 1/(x*(x - 1/x)))*((-(x - 1/x)/(x*(x | |
- 1/x)) - 1/x)*((x - 1/x)/((x*(x - 1/x)**2)) - 1/(x*(x - 1/x)))/(2*x - | |
(-x + 1/x)/(x**2*(x - 1/x)**2) - 1/(x**2*(x - 1/x)) - 2/x) - 1 + (x - | |
1/x)/(x - 1/x))/((x*((x - 1/x)/((x - 1/x)**2) - ((x - 1/x)/((x*(x - | |
1/x)**2)) - 1/(x*(x - 1/x)))**2/(2*x - (-x + 1/x)/(x**2*(x - 1/x)**2) | |
- 1/(x**2*(x - 1/x)) - 2/x) - 1/(x - 1/x))*(2*x - (-x + 1/x)/(x**2*(x | |
- 1/x)**2) - 1/(x**2*(x - 1/x)) - 2/x))) - 2*((x - 1/x)/((x*(x - | |
1/x))) + 1/x)/(x*(2*x - (-x + 1/x)/(x**2*(x - 1/x)**2) - 1/(x**2*(x - | |
1/x)) - 2/x)) - 2/x) - ((x - 1/x)/((x*(x - 1/x)**2)) - 1/(x*(x - | |
1/x)))*((-x + 1/x)*((x - 1/x)/((x*(x - 1/x)**2)) - 1/(x*(x - | |
1/x)))/(2*x - (-x + 1/x)/(x**2*(x - 1/x)**2) - 1/(x**2*(x - 1/x)) - | |
2/x) + 1)/(x*((x - 1/x)/((x - 1/x)**2) - ((x - 1/x)/((x*(x - 1/x)**2)) | |
- 1/(x*(x - 1/x)))**2/(2*x - (-x + 1/x)/(x**2*(x - 1/x)**2) - | |
1/(x**2*(x - 1/x)) - 2/x) - 1/(x - 1/x))*(2*x - (-x + 1/x)/(x**2*(x - | |
1/x)**2) - 1/(x**2*(x - 1/x)) - 2/x)) + (x - 1/x)/((x*(2*x - (-x + | |
1/x)/(x**2*(x - 1/x)**2) - 1/(x**2*(x - 1/x)) - 2/x))) - 1/x''', | |
evaluate=False) | |
assert cancel(q, _signsimp=False) is S.NaN | |
assert q.subs(x, 2) is S.NaN | |
assert signsimp(q) is S.NaN | |
# 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_make_monic_over_integers_by_scaling_roots(): | |
f = Poly(x**2 + 3*x + 4, x, domain='ZZ') | |
g, c = f.make_monic_over_integers_by_scaling_roots() | |
assert g == f | |
assert c == ZZ.one | |
f = Poly(x**2 + 3*x + 4, x, domain='QQ') | |
g, c = f.make_monic_over_integers_by_scaling_roots() | |
assert g == f.to_ring() | |
assert c == ZZ.one | |
f = Poly(x**2/2 + S(1)/4 * x + S(1)/8, x, domain='QQ') | |
g, c = f.make_monic_over_integers_by_scaling_roots() | |
assert g == Poly(x**2 + 2*x + 4, x, domain='ZZ') | |
assert c == 4 | |
f = Poly(x**3/2 + S(1)/4 * x + S(1)/8, x, domain='QQ') | |
g, c = f.make_monic_over_integers_by_scaling_roots() | |
assert g == Poly(x**3 + 8*x + 16, x, domain='ZZ') | |
assert c == 4 | |
f = Poly(x*y, x, y) | |
raises(ValueError, lambda: f.make_monic_over_integers_by_scaling_roots()) | |
f = Poly(x, domain='RR') | |
raises(ValueError, lambda: f.make_monic_over_integers_by_scaling_roots()) | |
def test_galois_group(): | |
f = Poly(x ** 4 - 2) | |
G, alt = f.galois_group(by_name=True) | |
assert G == S4TransitiveSubgroups.D4 | |
assert alt is False | |
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) | |
# https://github.com/sympy/sympy/issues/19755 | |
expr1 = x + (2*x + 3)**2/5 + S(6)/5 | |
assert poly(expr1).as_expr() == expr1.expand() | |
expr2 = y*(y+1) + S(1)/3 | |
assert poly(expr2).as_expr() == expr2.expand() | |
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(SymPyDeprecationWarning, test_stacklevel=False): | |
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.core.symbol import symbols | |
w, R = symbols('w R') | |
poly = Poly(1.0 + I*w/R, w, 1/R) | |
assert poly.degree() == S(1) | |