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from sympy.assumptions.ask import Q
from sympy.assumptions.refine import refine
from sympy.core.numbers import oo
from sympy.core.relational import Equality, Eq, Ne
from sympy.core.singleton import S
from sympy.core.symbol import (Dummy, symbols)
from sympy.functions import Piecewise
from sympy.functions.elementary.trigonometric import cos, sin
from sympy.sets.sets import (Interval, Union)
from sympy.simplify.simplify import simplify
from sympy.logic.boolalg import (
And, Boolean, Equivalent, ITE, Implies, Nand, Nor, Not, Or,
POSform, SOPform, Xor, Xnor, conjuncts, disjuncts,
distribute_or_over_and, distribute_and_over_or,
eliminate_implications, is_nnf, is_cnf, is_dnf, simplify_logic,
to_nnf, to_cnf, to_dnf, to_int_repr, bool_map, true, false,
BooleanAtom, is_literal, term_to_integer,
truth_table, as_Boolean, to_anf, is_anf, distribute_xor_over_and,
anf_coeffs, ANFform, bool_minterm, bool_maxterm, bool_monomial,
_check_pair, _convert_to_varsSOP, _convert_to_varsPOS, Exclusive,
gateinputcount)
from sympy.assumptions.cnf import CNF
from sympy.testing.pytest import raises, XFAIL, slow
from itertools import combinations, permutations, product
A, B, C, D = symbols('A:D')
a, b, c, d, e, w, x, y, z = symbols('a:e w:z')
def test_overloading():
"""Test that |, & are overloaded as expected"""
assert A & B == And(A, B)
assert A | B == Or(A, B)
assert (A & B) | C == Or(And(A, B), C)
assert A >> B == Implies(A, B)
assert A << B == Implies(B, A)
assert ~A == Not(A)
assert A ^ B == Xor(A, B)
def test_And():
assert And() is true
assert And(A) == A
assert And(True) is true
assert And(False) is false
assert And(True, True) is true
assert And(True, False) is false
assert And(False, False) is false
assert And(True, A) == A
assert And(False, A) is false
assert And(True, True, True) is true
assert And(True, True, A) == A
assert And(True, False, A) is false
assert And(1, A) == A
raises(TypeError, lambda: And(2, A))
raises(TypeError, lambda: And(A < 2, A))
assert And(A < 1, A >= 1) is false
e = A > 1
assert And(e, e.canonical) == e.canonical
g, l, ge, le = A > B, B < A, A >= B, B <= A
assert And(g, l, ge, le) == And(ge, g)
assert {And(*i) for i in permutations((l,g,le,ge))} == {And(ge, g)}
assert And(And(Eq(a, 0), Eq(b, 0)), And(Ne(a, 0), Eq(c, 0))) is false
def test_Or():
assert Or() is false
assert Or(A) == A
assert Or(True) is true
assert Or(False) is false
assert Or(True, True) is true
assert Or(True, False) is true
assert Or(False, False) is false
assert Or(True, A) is true
assert Or(False, A) == A
assert Or(True, False, False) is true
assert Or(True, False, A) is true
assert Or(False, False, A) == A
assert Or(1, A) is true
raises(TypeError, lambda: Or(2, A))
raises(TypeError, lambda: Or(A < 2, A))
assert Or(A < 1, A >= 1) is true
e = A > 1
assert Or(e, e.canonical) == e
g, l, ge, le = A > B, B < A, A >= B, B <= A
assert Or(g, l, ge, le) == Or(g, ge)
def test_Xor():
assert Xor() is false
assert Xor(A) == A
assert Xor(A, A) is false
assert Xor(True, A, A) is true
assert Xor(A, A, A, A, A) == A
assert Xor(True, False, False, A, B) == ~Xor(A, B)
assert Xor(True) is true
assert Xor(False) is false
assert Xor(True, True) is false
assert Xor(True, False) is true
assert Xor(False, False) is false
assert Xor(True, A) == ~A
assert Xor(False, A) == A
assert Xor(True, False, False) is true
assert Xor(True, False, A) == ~A
assert Xor(False, False, A) == A
assert isinstance(Xor(A, B), Xor)
assert Xor(A, B, Xor(C, D)) == Xor(A, B, C, D)
assert Xor(A, B, Xor(B, C)) == Xor(A, C)
assert Xor(A < 1, A >= 1, B) == Xor(0, 1, B) == Xor(1, 0, B)
e = A > 1
assert Xor(e, e.canonical) == Xor(0, 0) == Xor(1, 1)
def test_rewrite_as_And():
expr = x ^ y
assert expr.rewrite(And) == (x | y) & (~x | ~y)
def test_rewrite_as_Or():
expr = x ^ y
assert expr.rewrite(Or) == (x & ~y) | (y & ~x)
def test_rewrite_as_Nand():
expr = (y & z) | (z & ~w)
assert expr.rewrite(Nand) == ~(~(y & z) & ~(z & ~w))
def test_rewrite_as_Nor():
expr = z & (y | ~w)
assert expr.rewrite(Nor) == ~(~z | ~(y | ~w))
def test_Not():
raises(TypeError, lambda: Not(True, False))
assert Not(True) is false
assert Not(False) is true
assert Not(0) is true
assert Not(1) is false
assert Not(2) is false
def test_Nand():
assert Nand() is false
assert Nand(A) == ~A
assert Nand(True) is false
assert Nand(False) is true
assert Nand(True, True) is false
assert Nand(True, False) is true
assert Nand(False, False) is true
assert Nand(True, A) == ~A
assert Nand(False, A) is true
assert Nand(True, True, True) is false
assert Nand(True, True, A) == ~A
assert Nand(True, False, A) is true
def test_Nor():
assert Nor() is true
assert Nor(A) == ~A
assert Nor(True) is false
assert Nor(False) is true
assert Nor(True, True) is false
assert Nor(True, False) is false
assert Nor(False, False) is true
assert Nor(True, A) is false
assert Nor(False, A) == ~A
assert Nor(True, True, True) is false
assert Nor(True, True, A) is false
assert Nor(True, False, A) is false
def test_Xnor():
assert Xnor() is true
assert Xnor(A) == ~A
assert Xnor(A, A) is true
assert Xnor(True, A, A) is false
assert Xnor(A, A, A, A, A) == ~A
assert Xnor(True) is false
assert Xnor(False) is true
assert Xnor(True, True) is true
assert Xnor(True, False) is false
assert Xnor(False, False) is true
assert Xnor(True, A) == A
assert Xnor(False, A) == ~A
assert Xnor(True, False, False) is false
assert Xnor(True, False, A) == A
assert Xnor(False, False, A) == ~A
def test_Implies():
raises(ValueError, lambda: Implies(A, B, C))
assert Implies(True, True) is true
assert Implies(True, False) is false
assert Implies(False, True) is true
assert Implies(False, False) is true
assert Implies(0, A) is true
assert Implies(1, 1) is true
assert Implies(1, 0) is false
assert A >> B == B << A
assert (A < 1) >> (A >= 1) == (A >= 1)
assert (A < 1) >> (S.One > A) is true
assert A >> A is true
def test_Equivalent():
assert Equivalent(A, B) == Equivalent(B, A) == Equivalent(A, B, A)
assert Equivalent() is true
assert Equivalent(A, A) == Equivalent(A) is true
assert Equivalent(True, True) == Equivalent(False, False) is true
assert Equivalent(True, False) == Equivalent(False, True) is false
assert Equivalent(A, True) == A
assert Equivalent(A, False) == Not(A)
assert Equivalent(A, B, True) == A & B
assert Equivalent(A, B, False) == ~A & ~B
assert Equivalent(1, A) == A
assert Equivalent(0, A) == Not(A)
assert Equivalent(A, Equivalent(B, C)) != Equivalent(Equivalent(A, B), C)
assert Equivalent(A < 1, A >= 1) is false
assert Equivalent(A < 1, A >= 1, 0) is false
assert Equivalent(A < 1, A >= 1, 1) is false
assert Equivalent(A < 1, S.One > A) == Equivalent(1, 1) == Equivalent(0, 0)
assert Equivalent(Equality(A, B), Equality(B, A)) is true
def test_Exclusive():
assert Exclusive(False, False, False) is true
assert Exclusive(True, False, False) is true
assert Exclusive(True, True, False) is false
assert Exclusive(True, True, True) is false
def test_equals():
assert Not(Or(A, B)).equals(And(Not(A), Not(B))) is True
assert Equivalent(A, B).equals((A >> B) & (B >> A)) is True
assert ((A | ~B) & (~A | B)).equals((~A & ~B) | (A & B)) is True
assert (A >> B).equals(~A >> ~B) is False
assert (A >> (B >> A)).equals(A >> (C >> A)) is False
raises(NotImplementedError, lambda: (A & B).equals(A > B))
def test_simplification_boolalg():
"""
Test working of simplification methods.
"""
set1 = [[0, 0, 1], [0, 1, 1], [1, 0, 0], [1, 1, 0]]
set2 = [[0, 0, 0], [0, 1, 0], [1, 0, 1], [1, 1, 1]]
assert SOPform([x, y, z], set1) == Or(And(Not(x), z), And(Not(z), x))
assert Not(SOPform([x, y, z], set2)) == \
Not(Or(And(Not(x), Not(z)), And(x, z)))
assert POSform([x, y, z], set1 + set2) is true
assert SOPform([x, y, z], set1 + set2) is true
assert SOPform([Dummy(), Dummy(), Dummy()], set1 + set2) is true
minterms = [[0, 0, 0, 1], [0, 0, 1, 1], [0, 1, 1, 1], [1, 0, 1, 1],
[1, 1, 1, 1]]
dontcares = [[0, 0, 0, 0], [0, 0, 1, 0], [0, 1, 0, 1]]
assert (
SOPform([w, x, y, z], minterms, dontcares) ==
Or(And(y, z), And(Not(w), Not(x))))
assert POSform([w, x, y, z], minterms, dontcares) == And(Or(Not(w), y), z)
minterms = [1, 3, 7, 11, 15]
dontcares = [0, 2, 5]
assert (
SOPform([w, x, y, z], minterms, dontcares) ==
Or(And(y, z), And(Not(w), Not(x))))
assert POSform([w, x, y, z], minterms, dontcares) == And(Or(Not(w), y), z)
minterms = [1, [0, 0, 1, 1], 7, [1, 0, 1, 1],
[1, 1, 1, 1]]
dontcares = [0, [0, 0, 1, 0], 5]
assert (
SOPform([w, x, y, z], minterms, dontcares) ==
Or(And(y, z), And(Not(w), Not(x))))
assert POSform([w, x, y, z], minterms, dontcares) == And(Or(Not(w), y), z)
minterms = [1, {y: 1, z: 1}]
dontcares = [0, [0, 0, 1, 0], 5]
assert (
SOPform([w, x, y, z], minterms, dontcares) ==
Or(And(y, z), And(Not(w), Not(x))))
assert POSform([w, x, y, z], minterms, dontcares) == And(Or(Not(w), y), z)
minterms = [{y: 1, z: 1}, 1]
dontcares = [[0, 0, 0, 0]]
minterms = [[0, 0, 0]]
raises(ValueError, lambda: SOPform([w, x, y, z], minterms))
raises(ValueError, lambda: POSform([w, x, y, z], minterms))
raises(TypeError, lambda: POSform([w, x, y, z], ["abcdefg"]))
# test simplification
ans = And(A, Or(B, C))
assert simplify_logic(A & (B | C)) == ans
assert simplify_logic((A & B) | (A & C)) == ans
assert simplify_logic(Implies(A, B)) == Or(Not(A), B)
assert simplify_logic(Equivalent(A, B)) == \
Or(And(A, B), And(Not(A), Not(B)))
assert simplify_logic(And(Equality(A, 2), C)) == And(Equality(A, 2), C)
assert simplify_logic(And(Equality(A, 2), A)) is S.false
assert simplify_logic(And(Equality(A, 2), A)) == And(Equality(A, 2), A)
assert simplify_logic(And(Equality(A, B), C)) == And(Equality(A, B), C)
assert simplify_logic(Or(And(Equality(A, 3), B), And(Equality(A, 3), C))) \
== And(Equality(A, 3), Or(B, C))
b = (~x & ~y & ~z) | (~x & ~y & z)
e = And(A, b)
assert simplify_logic(e) == A & ~x & ~y
raises(ValueError, lambda: simplify_logic(A & (B | C), form='blabla'))
assert simplify(Or(x <= y, And(x < y, z))) == (x <= y)
assert simplify(Or(x <= y, And(y > x, z))) == (x <= y)
assert simplify(Or(x >= y, And(y < x, z))) == (x >= y)
# Check that expressions with nine variables or more are not simplified
# (without the force-flag)
a, b, c, d, e, f, g, h, j = symbols('a b c d e f g h j')
expr = a & b & c & d & e & f & g & h & j | \
a & b & c & d & e & f & g & h & ~j
# This expression can be simplified to get rid of the j variables
assert simplify_logic(expr) == expr
# Test dontcare
assert simplify_logic((a & b) | c | d, dontcare=(a & b)) == c | d
# check input
ans = SOPform([x, y], [[1, 0]])
assert SOPform([x, y], [[1, 0]]) == ans
assert POSform([x, y], [[1, 0]]) == ans
raises(ValueError, lambda: SOPform([x], [[1]], [[1]]))
assert SOPform([x], [[1]], [[0]]) is true
assert SOPform([x], [[0]], [[1]]) is true
assert SOPform([x], [], []) is false
raises(ValueError, lambda: POSform([x], [[1]], [[1]]))
assert POSform([x], [[1]], [[0]]) is true
assert POSform([x], [[0]], [[1]]) is true
assert POSform([x], [], []) is false
# check working of simplify
assert simplify((A & B) | (A & C)) == And(A, Or(B, C))
assert simplify(And(x, Not(x))) == False
assert simplify(Or(x, Not(x))) == True
assert simplify(And(Eq(x, 0), Eq(x, y))) == And(Eq(x, 0), Eq(y, 0))
assert And(Eq(x - 1, 0), Eq(x, y)).simplify() == And(Eq(x, 1), Eq(y, 1))
assert And(Ne(x - 1, 0), Ne(x, y)).simplify() == And(Ne(x, 1), Ne(x, y))
assert And(Eq(x - 1, 0), Ne(x, y)).simplify() == And(Eq(x, 1), Ne(y, 1))
assert And(Eq(x - 1, 0), Eq(x, z + y), Eq(y + x, 0)).simplify(
) == And(Eq(x, 1), Eq(y, -1), Eq(z, 2))
assert And(Eq(x - 1, 0), Eq(x + 2, 3)).simplify() == Eq(x, 1)
assert And(Ne(x - 1, 0), Ne(x + 2, 3)).simplify() == Ne(x, 1)
assert And(Eq(x - 1, 0), Eq(x + 2, 2)).simplify() == False
assert And(Ne(x - 1, 0), Ne(x + 2, 2)).simplify(
) == And(Ne(x, 1), Ne(x, 0))
def test_bool_map():
"""
Test working of bool_map function.
"""
minterms = [[0, 0, 0, 1], [0, 0, 1, 1], [0, 1, 1, 1], [1, 0, 1, 1],
[1, 1, 1, 1]]
assert bool_map(Not(Not(a)), a) == (a, {a: a})
assert bool_map(SOPform([w, x, y, z], minterms),
POSform([w, x, y, z], minterms)) == \
(And(Or(Not(w), y), Or(Not(x), y), z), {x: x, w: w, z: z, y: y})
assert bool_map(SOPform([x, z, y], [[1, 0, 1]]),
SOPform([a, b, c], [[1, 0, 1]])) != False
function1 = SOPform([x, z, y], [[1, 0, 1], [0, 0, 1]])
function2 = SOPform([a, b, c], [[1, 0, 1], [1, 0, 0]])
assert bool_map(function1, function2) == \
(function1, {y: a, z: b})
assert bool_map(Xor(x, y), ~Xor(x, y)) == False
assert bool_map(And(x, y), Or(x, y)) is None
assert bool_map(And(x, y), And(x, y, z)) is None
# issue 16179
assert bool_map(Xor(x, y, z), ~Xor(x, y, z)) == False
assert bool_map(Xor(a, x, y, z), ~Xor(a, x, y, z)) == False
def test_bool_symbol():
"""Test that mixing symbols with boolean values
works as expected"""
assert And(A, True) == A
assert And(A, True, True) == A
assert And(A, False) is false
assert And(A, True, False) is false
assert Or(A, True) is true
assert Or(A, False) == A
def test_is_boolean():
assert isinstance(True, Boolean) is False
assert isinstance(true, Boolean) is True
assert 1 == True
assert 1 != true
assert (1 == true) is False
assert 0 == False
assert 0 != false
assert (0 == false) is False
assert true.is_Boolean is True
assert (A & B).is_Boolean
assert (A | B).is_Boolean
assert (~A).is_Boolean
assert (A ^ B).is_Boolean
assert A.is_Boolean != isinstance(A, Boolean)
assert isinstance(A, Boolean)
def test_subs():
assert (A & B).subs(A, True) == B
assert (A & B).subs(A, False) is false
assert (A & B).subs(B, True) == A
assert (A & B).subs(B, False) is false
assert (A & B).subs({A: True, B: True}) is true
assert (A | B).subs(A, True) is true
assert (A | B).subs(A, False) == B
assert (A | B).subs(B, True) is true
assert (A | B).subs(B, False) == A
assert (A | B).subs({A: True, B: True}) is true
"""
we test for axioms of boolean algebra
see https://en.wikipedia.org/wiki/Boolean_algebra_(structure)
"""
def test_commutative():
"""Test for commutativity of And and Or"""
A, B = map(Boolean, symbols('A,B'))
assert A & B == B & A
assert A | B == B | A
def test_and_associativity():
"""Test for associativity of And"""
assert (A & B) & C == A & (B & C)
def test_or_assicativity():
assert ((A | B) | C) == (A | (B | C))
def test_double_negation():
a = Boolean()
assert ~(~a) == a
# test methods
def test_eliminate_implications():
assert eliminate_implications(Implies(A, B, evaluate=False)) == (~A) | B
assert eliminate_implications(
A >> (C >> Not(B))) == Or(Or(Not(B), Not(C)), Not(A))
assert eliminate_implications(Equivalent(A, B, C, D)) == \
(~A | B) & (~B | C) & (~C | D) & (~D | A)
def test_conjuncts():
assert conjuncts(A & B & C) == {A, B, C}
assert conjuncts((A | B) & C) == {A | B, C}
assert conjuncts(A) == {A}
assert conjuncts(True) == {True}
assert conjuncts(False) == {False}
def test_disjuncts():
assert disjuncts(A | B | C) == {A, B, C}
assert disjuncts((A | B) & C) == {(A | B) & C}
assert disjuncts(A) == {A}
assert disjuncts(True) == {True}
assert disjuncts(False) == {False}
def test_distribute():
assert distribute_and_over_or(Or(And(A, B), C)) == And(Or(A, C), Or(B, C))
assert distribute_or_over_and(And(A, Or(B, C))) == Or(And(A, B), And(A, C))
assert distribute_xor_over_and(And(A, Xor(B, C))) == Xor(And(A, B), And(A, C))
def test_to_anf():
x, y, z = symbols('x,y,z')
assert to_anf(And(x, y)) == And(x, y)
assert to_anf(Or(x, y)) == Xor(x, y, And(x, y))
assert to_anf(Or(Implies(x, y), And(x, y), y)) == \
Xor(x, True, x & y, remove_true=False)
assert to_anf(Or(Nand(x, y), Nor(x, y), Xnor(x, y), Implies(x, y))) == True
assert to_anf(Or(x, Not(y), Nor(x,z), And(x, y), Nand(y, z))) == \
Xor(True, And(y, z), And(x, y, z), remove_true=False)
assert to_anf(Xor(x, y)) == Xor(x, y)
assert to_anf(Not(x)) == Xor(x, True, remove_true=False)
assert to_anf(Nand(x, y)) == Xor(True, And(x, y), remove_true=False)
assert to_anf(Nor(x, y)) == Xor(x, y, True, And(x, y), remove_true=False)
assert to_anf(Implies(x, y)) == Xor(x, True, And(x, y), remove_true=False)
assert to_anf(Equivalent(x, y)) == Xor(x, y, True, remove_true=False)
assert to_anf(Nand(x | y, x >> y), deep=False) == \
Xor(True, And(Or(x, y), Implies(x, y)), remove_true=False)
assert to_anf(Nor(x ^ y, x & y), deep=False) == \
Xor(True, Or(Xor(x, y), And(x, y)), remove_true=False)
def test_to_nnf():
assert to_nnf(true) is true
assert to_nnf(false) is false
assert to_nnf(A) == A
assert to_nnf(A | ~A | B) is true
assert to_nnf(A & ~A & B) is false
assert to_nnf(A >> B) == ~A | B
assert to_nnf(Equivalent(A, B, C)) == (~A | B) & (~B | C) & (~C | A)
assert to_nnf(A ^ B ^ C) == \
(A | B | C) & (~A | ~B | C) & (A | ~B | ~C) & (~A | B | ~C)
assert to_nnf(ITE(A, B, C)) == (~A | B) & (A | C)
assert to_nnf(Not(A | B | C)) == ~A & ~B & ~C
assert to_nnf(Not(A & B & C)) == ~A | ~B | ~C
assert to_nnf(Not(A >> B)) == A & ~B
assert to_nnf(Not(Equivalent(A, B, C))) == And(Or(A, B, C), Or(~A, ~B, ~C))
assert to_nnf(Not(A ^ B ^ C)) == \
(~A | B | C) & (A | ~B | C) & (A | B | ~C) & (~A | ~B | ~C)
assert to_nnf(Not(ITE(A, B, C))) == (~A | ~B) & (A | ~C)
assert to_nnf((A >> B) ^ (B >> A)) == (A & ~B) | (~A & B)
assert to_nnf((A >> B) ^ (B >> A), False) == \
(~A | ~B | A | B) & ((A & ~B) | (~A & B))
assert ITE(A, 1, 0).to_nnf() == A
assert ITE(A, 0, 1).to_nnf() == ~A
# although ITE can hold non-Boolean, it will complain if
# an attempt is made to convert the ITE to Boolean nnf
raises(TypeError, lambda: ITE(A < 1, [1], B).to_nnf())
def test_to_cnf():
assert to_cnf(~(B | C)) == And(Not(B), Not(C))
assert to_cnf((A & B) | C) == And(Or(A, C), Or(B, C))
assert to_cnf(A >> B) == (~A) | B
assert to_cnf(A >> (B & C)) == (~A | B) & (~A | C)
assert to_cnf(A & (B | C) | ~A & (B | C), True) == B | C
assert to_cnf(A & B) == And(A, B)
assert to_cnf(Equivalent(A, B)) == And(Or(A, Not(B)), Or(B, Not(A)))
assert to_cnf(Equivalent(A, B & C)) == \
(~A | B) & (~A | C) & (~B | ~C | A)
assert to_cnf(Equivalent(A, B | C), True) == \
And(Or(Not(B), A), Or(Not(C), A), Or(B, C, Not(A)))
assert to_cnf(A + 1) == A + 1
def test_issue_18904():
x1, x2, x3, x4, x5, x6, x7, x8, x9, x10, x11, x12, x13, x14, x15 = symbols('x1:16')
eq = (( x1 & x2 & x3 & x4 & x5 & x6 & x7 & x8 & x9 ) |
( x1 & x2 & x3 & x4 & x5 & x6 & x7 & x10 & x9 ) |
( x1 & x11 & x3 & x12 & x5 & x13 & x14 & x15 & x9 ))
assert is_cnf(to_cnf(eq))
raises(ValueError, lambda: to_cnf(eq, simplify=True))
for f, t in zip((And, Or), (to_cnf, to_dnf)):
eq = f(x1, x2, x3, x4, x5, x6, x7, x8, x9)
raises(ValueError, lambda: to_cnf(eq, simplify=True))
assert t(eq, simplify=True, force=True) == eq
def test_issue_9949():
assert is_cnf(to_cnf((b > -5) | (a > 2) & (a < 4)))
def test_to_CNF():
assert CNF.CNF_to_cnf(CNF.to_CNF(~(B | C))) == to_cnf(~(B | C))
assert CNF.CNF_to_cnf(CNF.to_CNF((A & B) | C)) == to_cnf((A & B) | C)
assert CNF.CNF_to_cnf(CNF.to_CNF(A >> B)) == to_cnf(A >> B)
assert CNF.CNF_to_cnf(CNF.to_CNF(A >> (B & C))) == to_cnf(A >> (B & C))
assert CNF.CNF_to_cnf(CNF.to_CNF(A & (B | C) | ~A & (B | C))) == to_cnf(A & (B | C) | ~A & (B | C))
assert CNF.CNF_to_cnf(CNF.to_CNF(A & B)) == to_cnf(A & B)
def test_to_dnf():
assert to_dnf(~(B | C)) == And(Not(B), Not(C))
assert to_dnf(A & (B | C)) == Or(And(A, B), And(A, C))
assert to_dnf(A >> B) == (~A) | B
assert to_dnf(A >> (B & C)) == (~A) | (B & C)
assert to_dnf(A | B) == A | B
assert to_dnf(Equivalent(A, B), True) == \
Or(And(A, B), And(Not(A), Not(B)))
assert to_dnf(Equivalent(A, B & C), True) == \
Or(And(A, B, C), And(Not(A), Not(B)), And(Not(A), Not(C)))
assert to_dnf(A + 1) == A + 1
def test_to_int_repr():
x, y, z = map(Boolean, symbols('x,y,z'))
def sorted_recursive(arg):
try:
return sorted(sorted_recursive(x) for x in arg)
except TypeError: # arg is not a sequence
return arg
assert sorted_recursive(to_int_repr([x | y, z | x], [x, y, z])) == \
sorted_recursive([[1, 2], [1, 3]])
assert sorted_recursive(to_int_repr([x | y, z | ~x], [x, y, z])) == \
sorted_recursive([[1, 2], [3, -1]])
def test_is_anf():
x, y = symbols('x,y')
assert is_anf(true) is True
assert is_anf(false) is True
assert is_anf(x) is True
assert is_anf(And(x, y)) is True
assert is_anf(Xor(x, y, And(x, y))) is True
assert is_anf(Xor(x, y, Or(x, y))) is False
assert is_anf(Xor(Not(x), y)) is False
def test_is_nnf():
assert is_nnf(true) is True
assert is_nnf(A) is True
assert is_nnf(~A) is True
assert is_nnf(A & B) is True
assert is_nnf((A & B) | (~A & A) | (~B & B) | (~A & ~B), False) is True
assert is_nnf((A | B) & (~A | ~B)) is True
assert is_nnf(Not(Or(A, B))) is False
assert is_nnf(A ^ B) is False
assert is_nnf((A & B) | (~A & A) | (~B & B) | (~A & ~B), True) is False
def test_is_cnf():
assert is_cnf(x) is True
assert is_cnf(x | y | z) is True
assert is_cnf(x & y & z) is True
assert is_cnf((x | y) & z) is True
assert is_cnf((x & y) | z) is False
assert is_cnf(~(x & y) | z) is False
def test_is_dnf():
assert is_dnf(x) is True
assert is_dnf(x | y | z) is True
assert is_dnf(x & y & z) is True
assert is_dnf((x & y) | z) is True
assert is_dnf((x | y) & z) is False
assert is_dnf(~(x | y) & z) is False
def test_ITE():
A, B, C = symbols('A:C')
assert ITE(True, False, True) is false
assert ITE(True, True, False) is true
assert ITE(False, True, False) is false
assert ITE(False, False, True) is true
assert isinstance(ITE(A, B, C), ITE)
A = True
assert ITE(A, B, C) == B
A = False
assert ITE(A, B, C) == C
B = True
assert ITE(And(A, B), B, C) == C
assert ITE(Or(A, False), And(B, True), False) is false
assert ITE(x, A, B) == Not(x)
assert ITE(x, B, A) == x
assert ITE(1, x, y) == x
assert ITE(0, x, y) == y
raises(TypeError, lambda: ITE(2, x, y))
raises(TypeError, lambda: ITE(1, [], y))
raises(TypeError, lambda: ITE(1, (), y))
raises(TypeError, lambda: ITE(1, y, []))
assert ITE(1, 1, 1) is S.true
assert isinstance(ITE(1, 1, 1, evaluate=False), ITE)
raises(TypeError, lambda: ITE(x > 1, y, x))
assert ITE(Eq(x, True), y, x) == ITE(x, y, x)
assert ITE(Eq(x, False), y, x) == ITE(~x, y, x)
assert ITE(Ne(x, True), y, x) == ITE(~x, y, x)
assert ITE(Ne(x, False), y, x) == ITE(x, y, x)
assert ITE(Eq(S. true, x), y, x) == ITE(x, y, x)
assert ITE(Eq(S.false, x), y, x) == ITE(~x, y, x)
assert ITE(Ne(S.true, x), y, x) == ITE(~x, y, x)
assert ITE(Ne(S.false, x), y, x) == ITE(x, y, x)
# 0 and 1 in the context are not treated as True/False
# so the equality must always be False since dissimilar
# objects cannot be equal
assert ITE(Eq(x, 0), y, x) == x
assert ITE(Eq(x, 1), y, x) == x
assert ITE(Ne(x, 0), y, x) == y
assert ITE(Ne(x, 1), y, x) == y
assert ITE(Eq(x, 0), y, z).subs(x, 0) == y
assert ITE(Eq(x, 0), y, z).subs(x, 1) == z
raises(ValueError, lambda: ITE(x > 1, y, x, z))
def test_is_literal():
assert is_literal(True) is True
assert is_literal(False) is True
assert is_literal(A) is True
assert is_literal(~A) is True
assert is_literal(Or(A, B)) is False
assert is_literal(Q.zero(A)) is True
assert is_literal(Not(Q.zero(A))) is True
assert is_literal(Or(A, B)) is False
assert is_literal(And(Q.zero(A), Q.zero(B))) is False
assert is_literal(x < 3)
assert not is_literal(x + y < 3)
def test_operators():
# Mostly test __and__, __rand__, and so on
assert True & A == A & True == A
assert False & A == A & False == False
assert A & B == And(A, B)
assert True | A == A | True == True
assert False | A == A | False == A
assert A | B == Or(A, B)
assert ~A == Not(A)
assert True >> A == A << True == A
assert False >> A == A << False == True
assert A >> True == True << A == True
assert A >> False == False << A == ~A
assert A >> B == B << A == Implies(A, B)
assert True ^ A == A ^ True == ~A
assert False ^ A == A ^ False == A
assert A ^ B == Xor(A, B)
def test_true_false():
assert true is S.true
assert false is S.false
assert true is not True
assert false is not False
assert true
assert not false
assert true == True
assert false == False
assert not (true == False)
assert not (false == True)
assert not (true == false)
assert hash(true) == hash(True)
assert hash(false) == hash(False)
assert len({true, True}) == len({false, False}) == 1
assert isinstance(true, BooleanAtom)
assert isinstance(false, BooleanAtom)
# We don't want to subclass from bool, because bool subclasses from
# int. But operators like &, |, ^, <<, >>, and ~ act differently on 0 and
# 1 then we want them to on true and false. See the docstrings of the
# various And, Or, etc. functions for examples.
assert not isinstance(true, bool)
assert not isinstance(false, bool)
# Note: using 'is' comparison is important here. We want these to return
# true and false, not True and False
assert Not(true) is false
assert Not(True) is false
assert Not(false) is true
assert Not(False) is true
assert ~true is false
assert ~false is true
for T, F in product((True, true), (False, false)):
assert And(T, F) is false
assert And(F, T) is false
assert And(F, F) is false
assert And(T, T) is true
assert And(T, x) == x
assert And(F, x) is false
if not (T is True and F is False):
assert T & F is false
assert F & T is false
if F is not False:
assert F & F is false
if T is not True:
assert T & T is true
assert Or(T, F) is true
assert Or(F, T) is true
assert Or(F, F) is false
assert Or(T, T) is true
assert Or(T, x) is true
assert Or(F, x) == x
if not (T is True and F is False):
assert T | F is true
assert F | T is true
if F is not False:
assert F | F is false
if T is not True:
assert T | T is true
assert Xor(T, F) is true
assert Xor(F, T) is true
assert Xor(F, F) is false
assert Xor(T, T) is false
assert Xor(T, x) == ~x
assert Xor(F, x) == x
if not (T is True and F is False):
assert T ^ F is true
assert F ^ T is true
if F is not False:
assert F ^ F is false
if T is not True:
assert T ^ T is false
assert Nand(T, F) is true
assert Nand(F, T) is true
assert Nand(F, F) is true
assert Nand(T, T) is false
assert Nand(T, x) == ~x
assert Nand(F, x) is true
assert Nor(T, F) is false
assert Nor(F, T) is false
assert Nor(F, F) is true
assert Nor(T, T) is false
assert Nor(T, x) is false
assert Nor(F, x) == ~x
assert Implies(T, F) is false
assert Implies(F, T) is true
assert Implies(F, F) is true
assert Implies(T, T) is true
assert Implies(T, x) == x
assert Implies(F, x) is true
assert Implies(x, T) is true
assert Implies(x, F) == ~x
if not (T is True and F is False):
assert T >> F is false
assert F << T is false
assert F >> T is true
assert T << F is true
if F is not False:
assert F >> F is true
assert F << F is true
if T is not True:
assert T >> T is true
assert T << T is true
assert Equivalent(T, F) is false
assert Equivalent(F, T) is false
assert Equivalent(F, F) is true
assert Equivalent(T, T) is true
assert Equivalent(T, x) == x
assert Equivalent(F, x) == ~x
assert Equivalent(x, T) == x
assert Equivalent(x, F) == ~x
assert ITE(T, T, T) is true
assert ITE(T, T, F) is true
assert ITE(T, F, T) is false
assert ITE(T, F, F) is false
assert ITE(F, T, T) is true
assert ITE(F, T, F) is false
assert ITE(F, F, T) is true
assert ITE(F, F, F) is false
assert all(i.simplify(1, 2) is i for i in (S.true, S.false))
def test_bool_as_set():
assert ITE(y <= 0, False, y >= 1).as_set() == Interval(1, oo)
assert And(x <= 2, x >= -2).as_set() == Interval(-2, 2)
assert Or(x >= 2, x <= -2).as_set() == Interval(-oo, -2) + Interval(2, oo)
assert Not(x > 2).as_set() == Interval(-oo, 2)
# issue 10240
assert Not(And(x > 2, x < 3)).as_set() == \
Union(Interval(-oo, 2), Interval(3, oo))
assert true.as_set() == S.UniversalSet
assert false.as_set() is S.EmptySet
assert x.as_set() == S.UniversalSet
assert And(Or(x < 1, x > 3), x < 2).as_set() == Interval.open(-oo, 1)
assert And(x < 1, sin(x) < 3).as_set() == (x < 1).as_set()
raises(NotImplementedError, lambda: (sin(x) < 1).as_set())
# watch for object morph in as_set
assert Eq(-1, cos(2*x)**2/sin(2*x)**2).as_set() is S.EmptySet
@XFAIL
def test_multivariate_bool_as_set():
x, y = symbols('x,y')
assert And(x >= 0, y >= 0).as_set() == Interval(0, oo)*Interval(0, oo)
assert Or(x >= 0, y >= 0).as_set() == S.Reals*S.Reals - \
Interval(-oo, 0, True, True)*Interval(-oo, 0, True, True)
def test_all_or_nothing():
x = symbols('x', extended_real=True)
args = x >= -oo, x <= oo
v = And(*args)
if v.func is And:
assert len(v.args) == len(args) - args.count(S.true)
else:
assert v == True
v = Or(*args)
if v.func is Or:
assert len(v.args) == 2
else:
assert v == True
def test_canonical_atoms():
assert true.canonical == true
assert false.canonical == false
def test_negated_atoms():
assert true.negated == false
assert false.negated == true
def test_issue_8777():
assert And(x > 2, x < oo).as_set() == Interval(2, oo, left_open=True)
assert And(x >= 1, x < oo).as_set() == Interval(1, oo)
assert (x < oo).as_set() == Interval(-oo, oo)
assert (x > -oo).as_set() == Interval(-oo, oo)
def test_issue_8975():
assert Or(And(-oo < x, x <= -2), And(2 <= x, x < oo)).as_set() == \
Interval(-oo, -2) + Interval(2, oo)
def test_term_to_integer():
assert term_to_integer([1, 0, 1, 0, 0, 1, 0]) == 82
assert term_to_integer('0010101000111001') == 10809
def test_issue_21971():
a, b, c, d = symbols('a b c d')
f = a & b & c | a & c
assert f.subs(a & c, d) == b & d | d
assert f.subs(a & b & c, d) == a & c | d
f = (a | b | c) & (a | c)
assert f.subs(a | c, d) == (b | d) & d
assert f.subs(a | b | c, d) == (a | c) & d
f = (a ^ b ^ c) & (a ^ c)
assert f.subs(a ^ c, d) == (b ^ d) & d
assert f.subs(a ^ b ^ c, d) == (a ^ c) & d
def test_truth_table():
assert list(truth_table(And(x, y), [x, y], input=False)) == \
[False, False, False, True]
assert list(truth_table(x | y, [x, y], input=False)) == \
[False, True, True, True]
assert list(truth_table(x >> y, [x, y], input=False)) == \
[True, True, False, True]
assert list(truth_table(And(x, y), [x, y])) == \
[([0, 0], False), ([0, 1], False), ([1, 0], False), ([1, 1], True)]
def test_issue_8571():
for t in (S.true, S.false):
raises(TypeError, lambda: +t)
raises(TypeError, lambda: -t)
raises(TypeError, lambda: abs(t))
# use int(bool(t)) to get 0 or 1
raises(TypeError, lambda: int(t))
for o in [S.Zero, S.One, x]:
for _ in range(2):
raises(TypeError, lambda: o + t)
raises(TypeError, lambda: o - t)
raises(TypeError, lambda: o % t)
raises(TypeError, lambda: o*t)
raises(TypeError, lambda: o/t)
raises(TypeError, lambda: o**t)
o, t = t, o # do again in reversed order
def test_expand_relational():
n = symbols('n', negative=True)
p, q = symbols('p q', positive=True)
r = ((n + q*(-n/q + 1))/(q*(-n/q + 1)) < 0)
assert r is not S.false
assert r.expand() is S.false
assert (q > 0).expand() is S.true
def test_issue_12717():
assert S.true.is_Atom == True
assert S.false.is_Atom == True
def test_as_Boolean():
nz = symbols('nz', nonzero=True)
assert all(as_Boolean(i) is S.true for i in (True, S.true, 1, nz))
z = symbols('z', zero=True)
assert all(as_Boolean(i) is S.false for i in (False, S.false, 0, z))
assert all(as_Boolean(i) == i for i in (x, x < 0))
for i in (2, S(2), x + 1, []):
raises(TypeError, lambda: as_Boolean(i))
def test_binary_symbols():
assert ITE(x < 1, y, z).binary_symbols == {y, z}
for f in (Eq, Ne):
assert f(x, 1).binary_symbols == set()
assert f(x, True).binary_symbols == {x}
assert f(x, False).binary_symbols == {x}
assert S.true.binary_symbols == set()
assert S.false.binary_symbols == set()
assert x.binary_symbols == {x}
assert And(x, Eq(y, False), Eq(z, 1)).binary_symbols == {x, y}
assert Q.prime(x).binary_symbols == set()
assert Q.lt(x, 1).binary_symbols == set()
assert Q.is_true(x).binary_symbols == {x}
assert Q.eq(x, True).binary_symbols == {x}
assert Q.prime(x).binary_symbols == set()
def test_BooleanFunction_diff():
assert And(x, y).diff(x) == Piecewise((0, Eq(y, False)), (1, True))
def test_issue_14700():
A, B, C, D, E, F, G, H = symbols('A B C D E F G H')
q = ((B & D & H & ~F) | (B & H & ~C & ~D) | (B & H & ~C & ~F) |
(B & H & ~D & ~G) | (B & H & ~F & ~G) | (C & G & ~B & ~D) |
(C & G & ~D & ~H) | (C & G & ~F & ~H) | (D & F & H & ~B) |
(D & F & ~G & ~H) | (B & D & F & ~C & ~H) | (D & E & F & ~B & ~C) |
(D & F & ~A & ~B & ~C) | (D & F & ~A & ~C & ~H) |
(A & B & D & F & ~E & ~H))
soldnf = ((B & D & H & ~F) | (D & F & H & ~B) | (B & H & ~C & ~D) |
(B & H & ~D & ~G) | (C & G & ~B & ~D) | (C & G & ~D & ~H) |
(C & G & ~F & ~H) | (D & F & ~G & ~H) | (D & E & F & ~C & ~H) |
(D & F & ~A & ~C & ~H) | (A & B & D & F & ~E & ~H))
solcnf = ((B | C | D) & (B | D | G) & (C | D | H) & (C | F | H) &
(D | G | H) & (F | G | H) & (B | F | ~D | ~H) &
(~B | ~D | ~F | ~H) & (D | ~B | ~C | ~G | ~H) &
(A | H | ~C | ~D | ~F | ~G) & (H | ~C | ~D | ~E | ~F | ~G) &
(B | E | H | ~A | ~D | ~F | ~G))
assert simplify_logic(q, "dnf") == soldnf
assert simplify_logic(q, "cnf") == solcnf
minterms = [[0, 1, 0, 0], [0, 1, 0, 1], [0, 1, 1, 0], [0, 1, 1, 1],
[0, 0, 1, 1], [1, 0, 1, 1]]
dontcares = [[1, 0, 0, 0], [1, 0, 0, 1], [1, 1, 0, 0], [1, 1, 0, 1]]
assert SOPform([w, x, y, z], minterms) == (x & ~w) | (y & z & ~x)
# Should not be more complicated with don't cares
assert SOPform([w, x, y, z], minterms, dontcares) == \
(x & ~w) | (y & z & ~x)
def test_relational_simplification():
w, x, y, z = symbols('w x y z', real=True)
d, e = symbols('d e', real=False)
# Test all combinations or sign and order
assert Or(x >= y, x < y).simplify() == S.true
assert Or(x >= y, y > x).simplify() == S.true
assert Or(x >= y, -x > -y).simplify() == S.true
assert Or(x >= y, -y < -x).simplify() == S.true
assert Or(-x <= -y, x < y).simplify() == S.true
assert Or(-x <= -y, -x > -y).simplify() == S.true
assert Or(-x <= -y, y > x).simplify() == S.true
assert Or(-x <= -y, -y < -x).simplify() == S.true
assert Or(y <= x, x < y).simplify() == S.true
assert Or(y <= x, y > x).simplify() == S.true
assert Or(y <= x, -x > -y).simplify() == S.true
assert Or(y <= x, -y < -x).simplify() == S.true
assert Or(-y >= -x, x < y).simplify() == S.true
assert Or(-y >= -x, y > x).simplify() == S.true
assert Or(-y >= -x, -x > -y).simplify() == S.true
assert Or(-y >= -x, -y < -x).simplify() == S.true
assert Or(x < y, x >= y).simplify() == S.true
assert Or(y > x, x >= y).simplify() == S.true
assert Or(-x > -y, x >= y).simplify() == S.true
assert Or(-y < -x, x >= y).simplify() == S.true
assert Or(x < y, -x <= -y).simplify() == S.true
assert Or(-x > -y, -x <= -y).simplify() == S.true
assert Or(y > x, -x <= -y).simplify() == S.true
assert Or(-y < -x, -x <= -y).simplify() == S.true
assert Or(x < y, y <= x).simplify() == S.true
assert Or(y > x, y <= x).simplify() == S.true
assert Or(-x > -y, y <= x).simplify() == S.true
assert Or(-y < -x, y <= x).simplify() == S.true
assert Or(x < y, -y >= -x).simplify() == S.true
assert Or(y > x, -y >= -x).simplify() == S.true
assert Or(-x > -y, -y >= -x).simplify() == S.true
assert Or(-y < -x, -y >= -x).simplify() == S.true
# Some other tests
assert Or(x >= y, w < z, x <= y).simplify() == S.true
assert And(x >= y, x < y).simplify() == S.false
assert Or(x >= y, Eq(y, x)).simplify() == (x >= y)
assert And(x >= y, Eq(y, x)).simplify() == Eq(x, y)
assert And(Eq(x, y), x >= 1, 2 < y, y >= 5, z < y).simplify() == \
(Eq(x, y) & (x >= 1) & (y >= 5) & (y > z))
assert Or(Eq(x, y), x >= y, w < y, z < y).simplify() == \
(x >= y) | (y > z) | (w < y)
assert And(Eq(x, y), x >= y, w < y, y >= z, z < y).simplify() == \
Eq(x, y) & (y > z) & (w < y)
# assert And(Eq(x, y), x >= y, w < y, y >= z, z < y).simplify(relational_minmax=True) == \
# And(Eq(x, y), y > Max(w, z))
# assert Or(Eq(x, y), x >= 1, 2 < y, y >= 5, z < y).simplify(relational_minmax=True) == \
# (Eq(x, y) | (x >= 1) | (y > Min(2, z)))
assert And(Eq(x, y), x >= 1, 2 < y, y >= 5, z < y).simplify() == \
(Eq(x, y) & (x >= 1) & (y >= 5) & (y > z))
assert (Eq(x, y) & Eq(d, e) & (x >= y) & (d >= e)).simplify() == \
(Eq(x, y) & Eq(d, e) & (d >= e))
assert And(Eq(x, y), Eq(x, -y)).simplify() == And(Eq(x, 0), Eq(y, 0))
assert Xor(x >= y, x <= y).simplify() == Ne(x, y)
assert And(x > 1, x < -1, Eq(x, y)).simplify() == S.false
# From #16690
assert And(x >= y, Eq(y, 0)).simplify() == And(x >= 0, Eq(y, 0))
assert Or(Ne(x, 1), Ne(x, 2)).simplify() == S.true
assert And(Eq(x, 1), Ne(2, x)).simplify() == Eq(x, 1)
assert Or(Eq(x, 1), Ne(2, x)).simplify() == Ne(x, 2)
def test_issue_8373():
x = symbols('x', real=True)
assert Or(x < 1, x > -1).simplify() == S.true
assert Or(x < 1, x >= 1).simplify() == S.true
assert And(x < 1, x >= 1).simplify() == S.false
assert Or(x <= 1, x >= 1).simplify() == S.true
def test_issue_7950():
x = symbols('x', real=True)
assert And(Eq(x, 1), Eq(x, 2)).simplify() == S.false
@slow
def test_relational_simplification_numerically():
def test_simplification_numerically_function(original, simplified):
symb = original.free_symbols
n = len(symb)
valuelist = list(set(combinations(list(range(-(n-1), n))*n, n)))
for values in valuelist:
sublist = dict(zip(symb, values))
originalvalue = original.subs(sublist)
simplifiedvalue = simplified.subs(sublist)
assert originalvalue == simplifiedvalue, "Original: {}\nand"\
" simplified: {}\ndo not evaluate to the same value for {}"\
"".format(original, simplified, sublist)
w, x, y, z = symbols('w x y z', real=True)
d, e = symbols('d e', real=False)
expressions = (And(Eq(x, y), x >= y, w < y, y >= z, z < y),
And(Eq(x, y), x >= 1, 2 < y, y >= 5, z < y),
Or(Eq(x, y), x >= 1, 2 < y, y >= 5, z < y),
And(x >= y, Eq(y, x)),
Or(And(Eq(x, y), x >= y, w < y, Or(y >= z, z < y)),
And(Eq(x, y), x >= 1, 2 < y, y >= -1, z < y)),
(Eq(x, y) & Eq(d, e) & (x >= y) & (d >= e)),
)
for expression in expressions:
test_simplification_numerically_function(expression,
expression.simplify())
def test_relational_simplification_patterns_numerically():
from sympy.core import Wild
from sympy.logic.boolalg import _simplify_patterns_and, \
_simplify_patterns_or, _simplify_patterns_xor
a = Wild('a')
b = Wild('b')
c = Wild('c')
symb = [a, b, c]
patternlists = [[And, _simplify_patterns_and()],
[Or, _simplify_patterns_or()],
[Xor, _simplify_patterns_xor()]]
valuelist = list(set(combinations(list(range(-2, 3))*3, 3)))
# Skip combinations of +/-2 and 0, except for all 0
valuelist = [v for v in valuelist if any([w % 2 for w in v]) or not any(v)]
for func, patternlist in patternlists:
for pattern in patternlist:
original = func(*pattern[0].args)
simplified = pattern[1]
for values in valuelist:
sublist = dict(zip(symb, values))
originalvalue = original.xreplace(sublist)
simplifiedvalue = simplified.xreplace(sublist)
assert originalvalue == simplifiedvalue, "Original: {}\nand"\
" simplified: {}\ndo not evaluate to the same value for"\
"{}".format(pattern[0], simplified, sublist)
def test_issue_16803():
n = symbols('n')
# No simplification done, but should not raise an exception
assert ((n > 3) | (n < 0) | ((n > 0) & (n < 3))).simplify() == \
(n > 3) | (n < 0) | ((n > 0) & (n < 3))
def test_issue_17530():
r = {x: oo, y: oo}
assert Or(x + y > 0, x - y < 0).subs(r)
assert not And(x + y < 0, x - y < 0).subs(r)
raises(TypeError, lambda: Or(x + y < 0, x - y < 0).subs(r))
raises(TypeError, lambda: And(x + y > 0, x - y < 0).subs(r))
raises(TypeError, lambda: And(x + y > 0, x - y < 0).subs(r))
def test_anf_coeffs():
assert anf_coeffs([1, 0]) == [1, 1]
assert anf_coeffs([0, 0, 0, 1]) == [0, 0, 0, 1]
assert anf_coeffs([0, 1, 1, 1]) == [0, 1, 1, 1]
assert anf_coeffs([1, 1, 1, 0]) == [1, 0, 0, 1]
assert anf_coeffs([1, 0, 0, 0]) == [1, 1, 1, 1]
assert anf_coeffs([1, 0, 0, 1]) == [1, 1, 1, 0]
assert anf_coeffs([1, 1, 0, 1]) == [1, 0, 1, 1]
def test_ANFform():
x, y = symbols('x,y')
assert ANFform([x], [1, 1]) == True
assert ANFform([x], [0, 0]) == False
assert ANFform([x], [1, 0]) == Xor(x, True, remove_true=False)
assert ANFform([x, y], [1, 1, 1, 0]) == \
Xor(True, And(x, y), remove_true=False)
def test_bool_minterm():
x, y = symbols('x,y')
assert bool_minterm(3, [x, y]) == And(x, y)
assert bool_minterm([1, 0], [x, y]) == And(Not(y), x)
def test_bool_maxterm():
x, y = symbols('x,y')
assert bool_maxterm(2, [x, y]) == Or(Not(x), y)
assert bool_maxterm([0, 1], [x, y]) == Or(Not(y), x)
def test_bool_monomial():
x, y = symbols('x,y')
assert bool_monomial(1, [x, y]) == y
assert bool_monomial([1, 1], [x, y]) == And(x, y)
def test_check_pair():
assert _check_pair([0, 1, 0], [0, 1, 1]) == 2
assert _check_pair([0, 1, 0], [1, 1, 1]) == -1
def test_issue_19114():
expr = (B & C) | (A & ~C) | (~A & ~B)
# Expression is minimal, but there are multiple minimal forms possible
res1 = (A & B) | (C & ~A) | (~B & ~C)
result = to_dnf(expr, simplify=True)
assert result in (expr, res1)
def test_issue_20870():
result = SOPform([a, b, c, d], [1, 2, 3, 4, 5, 6, 8, 9, 11, 12, 14, 15])
expected = ((d & ~b) | (a & b & c) | (a & ~c & ~d) |
(b & ~a & ~c) | (c & ~a & ~d))
assert result == expected
def test_convert_to_varsSOP():
assert _convert_to_varsSOP([0, 1, 0], [x, y, z]) == And(Not(x), y, Not(z))
assert _convert_to_varsSOP([3, 1, 0], [x, y, z]) == And(y, Not(z))
def test_convert_to_varsPOS():
assert _convert_to_varsPOS([0, 1, 0], [x, y, z]) == Or(x, Not(y), z)
assert _convert_to_varsPOS([3, 1, 0], [x, y, z]) == Or(Not(y), z)
def test_gateinputcount():
a, b, c, d, e = symbols('a:e')
assert gateinputcount(And(a, b)) == 2
assert gateinputcount(a | b & c & d ^ (e | a)) == 9
assert gateinputcount(And(a, True)) == 0
raises(TypeError, lambda: gateinputcount(a*b))
def test_refine():
# relational
assert not refine(x < 0, ~(x < 0))
assert refine(x < 0, (x < 0))
assert refine(x < 0, (0 > x)) is S.true
assert refine(x < 0, (y < 0)) == (x < 0)
assert not refine(x <= 0, ~(x <= 0))
assert refine(x <= 0, (x <= 0))
assert refine(x <= 0, (0 >= x)) is S.true
assert refine(x <= 0, (y <= 0)) == (x <= 0)
assert not refine(x > 0, ~(x > 0))
assert refine(x > 0, (x > 0))
assert refine(x > 0, (0 < x)) is S.true
assert refine(x > 0, (y > 0)) == (x > 0)
assert not refine(x >= 0, ~(x >= 0))
assert refine(x >= 0, (x >= 0))
assert refine(x >= 0, (0 <= x)) is S.true
assert refine(x >= 0, (y >= 0)) == (x >= 0)
assert not refine(Eq(x, 0), ~(Eq(x, 0)))
assert refine(Eq(x, 0), (Eq(x, 0)))
assert refine(Eq(x, 0), (Eq(0, x))) is S.true
assert refine(Eq(x, 0), (Eq(y, 0))) == Eq(x, 0)
assert not refine(Ne(x, 0), ~(Ne(x, 0)))
assert refine(Ne(x, 0), (Ne(0, x))) is S.true
assert refine(Ne(x, 0), (Ne(x, 0)))
assert refine(Ne(x, 0), (Ne(y, 0))) == (Ne(x, 0))
# boolean functions
assert refine(And(x > 0, y > 0), (x > 0)) == (y > 0)
assert refine(And(x > 0, y > 0), (x > 0) & (y > 0)) is S.true
# predicates
assert refine(Q.positive(x), Q.positive(x)) is S.true
assert refine(Q.positive(x), Q.negative(x)) is S.false
assert refine(Q.positive(x), Q.real(x)) == Q.positive(x)
def test_relational_threeterm_simplification_patterns_numerically():
from sympy.core import Wild
from sympy.logic.boolalg import _simplify_patterns_and3
a = Wild('a')
b = Wild('b')
c = Wild('c')
symb = [a, b, c]
patternlists = [[And, _simplify_patterns_and3()]]
valuelist = list(set(combinations(list(range(-2, 3))*3, 3)))
# Skip combinations of +/-2 and 0, except for all 0
valuelist = [v for v in valuelist if any([w % 2 for w in v]) or not any(v)]
for func, patternlist in patternlists:
for pattern in patternlist:
original = func(*pattern[0].args)
simplified = pattern[1]
for values in valuelist:
sublist = dict(zip(symb, values))
originalvalue = original.xreplace(sublist)
simplifiedvalue = simplified.xreplace(sublist)
assert originalvalue == simplifiedvalue, "Original: {}\nand"\
" simplified: {}\ndo not evaluate to the same value for"\
"{}".format(pattern[0], simplified, sublist)