Spaces:
Sleeping
Sleeping
File size: 3,029 Bytes
6a86ad5 |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 |
from sympy.unify.core import Compound, Variable, CondVariable, allcombinations
from sympy.unify import core
a,b,c = 'a', 'b', 'c'
w,x,y,z = map(Variable, 'wxyz')
C = Compound
def is_associative(x):
return isinstance(x, Compound) and (x.op in ('Add', 'Mul', 'CAdd', 'CMul'))
def is_commutative(x):
return isinstance(x, Compound) and (x.op in ('CAdd', 'CMul'))
def unify(a, b, s={}):
return core.unify(a, b, s=s, is_associative=is_associative,
is_commutative=is_commutative)
def test_basic():
assert list(unify(a, x, {})) == [{x: a}]
assert list(unify(a, x, {x: 10})) == []
assert list(unify(1, x, {})) == [{x: 1}]
assert list(unify(a, a, {})) == [{}]
assert list(unify((w, x), (y, z), {})) == [{w: y, x: z}]
assert list(unify(x, (a, b), {})) == [{x: (a, b)}]
assert list(unify((a, b), (x, x), {})) == []
assert list(unify((y, z), (x, x), {}))!= []
assert list(unify((a, (b, c)), (a, (x, y)), {})) == [{x: b, y: c}]
def test_ops():
assert list(unify(C('Add', (a,b,c)), C('Add', (a,x,y)), {})) == \
[{x:b, y:c}]
assert list(unify(C('Add', (C('Mul', (1,2)), b,c)), C('Add', (x,y,c)), {})) == \
[{x: C('Mul', (1,2)), y:b}]
def test_associative():
c1 = C('Add', (1,2,3))
c2 = C('Add', (x,y))
assert tuple(unify(c1, c2, {})) == ({x: 1, y: C('Add', (2, 3))},
{x: C('Add', (1, 2)), y: 3})
def test_commutative():
c1 = C('CAdd', (1,2,3))
c2 = C('CAdd', (x,y))
result = list(unify(c1, c2, {}))
assert {x: 1, y: C('CAdd', (2, 3))} in result
assert ({x: 2, y: C('CAdd', (1, 3))} in result or
{x: 2, y: C('CAdd', (3, 1))} in result)
def _test_combinations_assoc():
assert set(allcombinations((1,2,3), (a,b), True)) == \
{(((1, 2), (3,)), (a, b)), (((1,), (2, 3)), (a, b))}
def _test_combinations_comm():
assert set(allcombinations((1,2,3), (a,b), None)) == \
{(((1,), (2, 3)), ('a', 'b')), (((2,), (3, 1)), ('a', 'b')),
(((3,), (1, 2)), ('a', 'b')), (((1, 2), (3,)), ('a', 'b')),
(((2, 3), (1,)), ('a', 'b')), (((3, 1), (2,)), ('a', 'b'))}
def test_allcombinations():
assert set(allcombinations((1,2), (1,2), 'commutative')) ==\
{(((1,),(2,)), ((1,),(2,))), (((1,),(2,)), ((2,),(1,)))}
def test_commutativity():
c1 = Compound('CAdd', (a, b))
c2 = Compound('CAdd', (x, y))
assert is_commutative(c1) and is_commutative(c2)
assert len(list(unify(c1, c2, {}))) == 2
def test_CondVariable():
expr = C('CAdd', (1, 2))
x = Variable('x')
y = CondVariable('y', lambda a: a % 2 == 0)
z = CondVariable('z', lambda a: a > 3)
pattern = C('CAdd', (x, y))
assert list(unify(expr, pattern, {})) == \
[{x: 1, y: 2}]
z = CondVariable('z', lambda a: a > 3)
pattern = C('CAdd', (z, y))
assert list(unify(expr, pattern, {})) == []
def test_defaultdict():
assert next(unify(Variable('x'), 'foo')) == {Variable('x'): 'foo'}
|