def generate_initial_beliefs():
"""Example premises is from exercises from lecture 9"""
p, q, s, r = symbols("p q s r")
return [Implies(Not(p), q), Implies(q, p), Implies(p, And(r, s))]
def get_known_facts(x=None):
"""
Facts between unary predicates.
Parameters
==========
x : Symbol, optional
Placeholder symbol for unary facts. Default is ``Symbol('x')``.
Returns
=======
fact : Known facts in conjugated normal form.
"""
if x is None:
x = Symbol('x')
fact = And(
# primitive predicates for extended real exclude each other.
Exclusive(Q.negative_infinite(x), Q.negative(x), Q.zero(x),
Q.positive(x), Q.positive_infinite(x)),
# build complex plane
Exclusive(Q.real(x), Q.imaginary(x)),
Implies(Q.real(x) | Q.imaginary(x), Q.complex(x)),
# other subsets of complex
Exclusive(Q.transcendental(x), Q.algebraic(x)),
Equivalent(Q.real(x),
Q.rational(x) | Q.irrational(x)),
Exclusive(Q.irrational(x), Q.rational(x)),
Implies(Q.rational(x), Q.algebraic(x)),
# integers
Exclusive(Q.even(x), Q.odd(x)),
Implies(Q.integer(x), Q.rational(x)),
Implies(Q.zero(x), Q.even(x)),
Exclusive(Q.composite(x), Q.prime(x)),
Implies(Q.composite(x) | Q.prime(x),
Q.integer(x) & Q.positive(x)),
Implies(Q.even(x) & Q.positive(x) & ~Q.prime(x), Q.composite(x)),
# hermitian and antihermitian
Implies(Q.real(x), Q.hermitian(x)),
Implies(Q.imaginary(x), Q.antihermitian(x)),
Implies(Q.zero(x),
Q.hermitian(x) | Q.antihermitian(x)),
# define finity and infinity, and build extended real line
Exclusive(Q.infinite(x), Q.finite(x)),
Implies(Q.complex(x), Q.finite(x)),
Implies(
Q.negative_infinite(x) | Q.positive_infinite(x), Q.infinite(x)),
# commutativity
Implies(Q.finite(x) | Q.infinite(x), Q.commutative(x)),
# matrices
Implies(Q.orthogonal(x), Q.positive_definite(x)),
Implies(Q.orthogonal(x), Q.unitary(x)),
Implies(Q.unitary(x) & Q.real_elements(x), Q.orthogonal(x)),
Implies(Q.unitary(x), Q.normal(x)),
Implies(Q.unitary(x), Q.invertible(x)),
Implies(Q.normal(x), Q.square(x)),
Implies(Q.diagonal(x), Q.normal(x)),
Implies(Q.positive_definite(x), Q.invertible(x)),
Implies(Q.diagonal(x), Q.upper_triangular(x)),
Implies(Q.diagonal(x), Q.lower_triangular(x)),
Implies(Q.lower_triangular(x), Q.triangular(x)),
Implies(Q.upper_triangular(x), Q.triangular(x)),
Implies(Q.triangular(x),
Q.upper_triangular(x) | Q.lower_triangular(x)),
Implies(Q.upper_triangular(x) & Q.lower_triangular(x), Q.diagonal(x)),
Implies(Q.diagonal(x), Q.symmetric(x)),
Implies(Q.unit_triangular(x), Q.triangular(x)),
Implies(Q.invertible(x), Q.fullrank(x)),
Implies(Q.invertible(x), Q.square(x)),
Implies(Q.symmetric(x), Q.square(x)),
Implies(Q.fullrank(x) & Q.square(x), Q.invertible(x)),
Equivalent(Q.invertible(x), ~Q.singular(x)),
Implies(Q.integer_elements(x), Q.real_elements(x)),
Implies(Q.real_elements(x), Q.complex_elements(x)),
)
return fact
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 get_known_facts():
return And(
Implies(Q.infinite, ~Q.finite),
Implies(Q.real, Q.complex),
Implies(Q.real, Q.hermitian),
Equivalent(Q.extended_real, Q.real | Q.infinite),
Equivalent(Q.even | Q.odd, Q.integer),
Implies(Q.even, ~Q.odd),
Equivalent(Q.prime, Q.integer & Q.positive & ~Q.composite),
Implies(Q.integer, Q.rational),
Implies(Q.rational, Q.algebraic),
Implies(Q.algebraic, Q.complex),
Implies(Q.algebraic, Q.finite),
Equivalent(Q.transcendental | Q.algebraic, Q.complex & Q.finite),
Implies(Q.transcendental, ~Q.algebraic),
Implies(Q.transcendental, Q.finite),
Implies(Q.imaginary, Q.complex & ~Q.real),
Implies(Q.imaginary, Q.antihermitian),
Implies(Q.antihermitian, ~Q.hermitian),
Equivalent(Q.irrational | Q.rational, Q.real & Q.finite),
Implies(Q.irrational, ~Q.rational),
Implies(Q.zero, Q.even),
Equivalent(Q.real, Q.negative | Q.zero | Q.positive),
Implies(Q.zero, ~Q.negative & ~Q.positive),
Implies(Q.negative, ~Q.positive),
Equivalent(Q.nonnegative, Q.zero | Q.positive),
Equivalent(Q.nonpositive, Q.zero | Q.negative),
Equivalent(Q.nonzero, Q.negative | Q.positive),
Implies(Q.orthogonal, Q.positive_definite),
Implies(Q.orthogonal, Q.unitary),
Implies(Q.unitary & Q.real, Q.orthogonal),
Implies(Q.unitary, Q.normal),
Implies(Q.unitary, Q.invertible),
Implies(Q.normal, Q.square),
Implies(Q.diagonal, Q.normal),
Implies(Q.positive_definite, Q.invertible),
Implies(Q.diagonal, Q.upper_triangular),
Implies(Q.diagonal, Q.lower_triangular),
Implies(Q.lower_triangular, Q.triangular),
Implies(Q.upper_triangular, Q.triangular),
Implies(Q.triangular, Q.upper_triangular | Q.lower_triangular),
Implies(Q.upper_triangular & Q.lower_triangular, Q.diagonal),
Implies(Q.diagonal, Q.symmetric),
Implies(Q.unit_triangular, Q.triangular),
Implies(Q.invertible, Q.fullrank),
Implies(Q.invertible, Q.square),
Implies(Q.symmetric, Q.square),
Implies(Q.fullrank & Q.square, Q.invertible),
Equivalent(Q.invertible, ~Q.singular),
Implies(Q.integer_elements, Q.real_elements),
Implies(Q.real_elements, Q.complex_elements),
)
("diagonal", "matrices.AskDiagonalHandler"),
("fullrank", "matrices.AskFullRankHandler"),
("square", "matrices.AskSquareHandler"),
("integer_elements", "matrices.AskIntegerElementsHandler"),
("real_elements", "matrices.AskRealElementsHandler"),
("complex_elements", "matrices.AskComplexElementsHandler"),
]
for name, value in _handlers:
register_handler(name, _val_template % value)
known_facts_keys = [
getattr(Q, attr) for attr in Q.__dict__ if not attr.startswith('__')
]
known_facts = And(
Implies(Q.real, Q.complex),
Implies(Q.real, Q.hermitian),
Equivalent(Q.even, Q.integer & ~Q.odd),
Equivalent(Q.extended_real, Q.real | Q.infinity),
Equivalent(Q.odd, Q.integer & ~Q.even),
Equivalent(Q.prime, Q.integer & Q.positive & ~Q.composite),
Implies(Q.integer, Q.rational),
Implies(Q.rational, Q.algebraic),
Implies(Q.algebraic, Q.complex),
Implies(Q.imaginary, Q.complex & ~Q.real),
Implies(Q.imaginary, Q.antihermitian),
Implies(Q.antihermitian, ~Q.hermitian),
Equivalent(Q.negative, Q.nonzero & ~Q.positive),
Equivalent(Q.positive, Q.nonzero & ~Q.negative),
Equivalent(Q.rational, Q.real & ~Q.irrational),
Equivalent(Q.real, Q.rational | Q.irrational),
'nonzero' : ['sympy.assumptions.handlers.order.AskNonZeroHandler'],
'positive' : ['sympy.assumptions.handlers.order.AskPositiveHandler'],
'prime' : ['sympy.assumptions.handlers.ntheory.AskPrimeHandler'],
'real' : ['sympy.assumptions.handlers.sets.AskRealHandler'],
'odd' : ['sympy.assumptions.handlers.ntheory.AskOddHandler'],
'algebraic' : ['sympy.assumptions.handlers.sets.AskAlgebraicHandler'],
'is_true' : ['sympy.assumptions.handlers.TautologicalHandler']
}
for name, value in _handlers_dict.iteritems():
register_handler(name, value[0])
known_facts_keys = [getattr(Q, attr) for attr in Q.__dict__ \
if not attr.startswith('__')]
known_facts = And(
Implies (Q.real, Q.complex),
Equivalent(Q.even, Q.integer & ~Q.odd),
Equivalent(Q.extended_real, Q.real | Q.infinity),
Equivalent(Q.odd, Q.integer & ~Q.even),
Equivalent(Q.prime, Q.integer & Q.positive & ~Q.composite),
Implies (Q.integer, Q.rational),
Implies (Q.imaginary, Q.complex & ~Q.real),
Equivalent(Q.negative, Q.nonzero & ~Q.positive),
Equivalent(Q.positive, Q.nonzero & ~Q.negative),
Equivalent(Q.rational, Q.real & ~Q.irrational),
Equivalent(Q.real, Q.rational | Q.irrational),
Implies (Q.nonzero, Q.real),
Equivalent(Q.nonzero, Q.positive | Q.negative)
)
################################################################################
'negative': ['sympy.assumptions.handlers.order.AskNegativeHandler'],
'nonzero': ['sympy.assumptions.handlers.order.AskNonZeroHandler'],
'positive': ['sympy.assumptions.handlers.order.AskPositiveHandler'],
'prime': ['sympy.assumptions.handlers.ntheory.AskPrimeHandler'],
'real': ['sympy.assumptions.handlers.sets.AskRealHandler'],
'odd': ['sympy.assumptions.handlers.ntheory.AskOddHandler'],
'algebraic': ['sympy.assumptions.handlers.sets.AskAlgebraicHandler'],
'is_true': ['sympy.assumptions.handlers.TautologicalHandler']
}
for name, value in _handlers_dict.iteritems():
register_handler(name, value[0])
known_facts_keys = [getattr(Q, attr) for attr in Q.__dict__ \
if not attr.startswith('__')]
known_facts = And(Implies(Q.real, Q.complex), Implies(Q.real, Q.hermitian),
Equivalent(Q.even, Q.integer & ~Q.odd),
Equivalent(Q.extended_real, Q.real | Q.infinity),
Equivalent(Q.odd, Q.integer & ~Q.even),
Equivalent(Q.prime, Q.integer & Q.positive & ~Q.composite),
Implies(Q.integer, Q.rational),
Implies(Q.imaginary, Q.complex & ~Q.real),
Implies(Q.imaginary, Q.antihermitian),
Implies(Q.antihermitian, ~Q.hermitian),
Equivalent(Q.negative, Q.nonzero & ~Q.positive),
Equivalent(Q.positive, Q.nonzero & ~Q.negative),
Equivalent(Q.rational, Q.real & ~Q.irrational),
Equivalent(Q.real, Q.rational | Q.irrational),
Implies(Q.nonzero, Q.real),
Equivalent(Q.nonzero, Q.positive | Q.negative))
def test_Implies(self):
assert Implies(true, false) is false
def test_Implies():
A, B, C = symbols('ABC')
Implies(True, True) == True
Implies(False, False) == False
assert A >> B == B << A
def Biconditional(a, b):
"""
rewrite biconditional as a new premise consisting of two implies according to formula in Peter Norvig & Stuart Russel Chapter 7
replacing alpha <=> beta with (alpha => beta) and (beta => alpha)
"""
return And(Implies(a, b), Implies(b, a))
def test_simplification():
"""
Test working of simplification methods.
"""
set1 = [[0, 0, 1], [0, 1, 1], [1, 0, 0], [1, 1, 0]]
set2 = [[0, 0, 0], [0, 1, 0], [1, 0, 1], [1, 1, 1]]
assert SOPform([x, y, z], set1) == Or(And(Not(x), z), And(Not(z), x))
assert Not(SOPform([x, y, z],
set2)) == Not(Or(And(Not(x), Not(z)), And(x, z)))
assert POSform([x, y, z], set1 + set2) is true
assert SOPform([x, y, z], set1 + set2) is true
assert SOPform([Dummy(), Dummy(), Dummy()], set1 + set2) is true
minterms = [[0, 0, 0, 1], [0, 0, 1, 1], [0, 1, 1, 1], [1, 0, 1, 1],
[1, 1, 1, 1]]
dontcares = [[0, 0, 0, 0], [0, 0, 1, 0], [0, 1, 0, 1]]
assert (SOPform([w, x, y, z], minterms,
dontcares) == Or(And(Not(w), z), And(y, z)))
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(Not(w), z), And(y, z)))
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(Not(w), z), And(y, z)))
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
# 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))
Xor(True, True)
Xor(True, False, True)
Xor(True, False, True, False)
Xor(True, False, True, False, True)
a, b = symbols('a b')
a ^ b
from sympy.logic.boolalg import Nand
Nand(True, False)
Nand(True, True)
Nand(a, b)
from sympy.logic.boolalg import Nor
Nor(True, False)
Nor(True, True)
Nor(False, True)
Nor(False, False)
Nor(a, b)
from sympy.logic.boolalg import Equivalent, And
Equivalent(False, False, False)
Equivalent(True, False, False)
Equivalent(a, And(a, True))
from sympy.logic.boolalg import Implies
Implies(False, True)
Implies(True, False)
Implies(False, False)
Implies(True, True)
a >> b
b << a
def __repr__(self):
return repr(self.d)
fact_registry = ClassFactRegistry()
def register_fact(klass, fact, registry=fact_registry):
registry[klass] |= set([fact])
for klass, fact in [
(Mul, Equivalent(Q.zero, AnyArgs(Q.zero))),
(MatMul,
Implies(AllArgs(Q.square), Equivalent(Q.invertible,
AllArgs(Q.invertible)))),
(Add, Implies(AllArgs(Q.positive), Q.positive)),
(Add, Implies(AllArgs(Q.negative), Q.negative)),
(Mul, Implies(AllArgs(Q.positive), Q.positive)),
(Mul, Implies(AllArgs(Q.commutative), Q.commutative)),
(Mul, Implies(AllArgs(Q.real), Q.commutative)),
# This one can still be made easier to read. I think we need basic pattern
# matching, so that we can just write Equivalent(Q.zero(x**y), Q.zero(x) & Q.positive(y))
(Pow,
CustomLambda(
lambda power: Equivalent(Q.zero(power),
Q.zero(power.base) & Q.positive(power.exp)))
),
(Integer, CheckIsPrime(Q.prime)),
# Implicitly assumes Mul has more than one arg
# Would be AllArgs(Q.prime | Q.composite) except 1 is composite
("is_true", "TautologicalHandler"),
("symmetric", "matrices.AskSymmetricHandler"),
("invertible", "matrices.AskInvertibleHandler"),
("orthogonal", "matrices.AskOrthogonalHandler"),
("positive_definite", "matrices.AskPositiveDefiniteHandler"),
("upper_triangular", "matrices.AskUpperTriangularHandler"),
("lower_triangular", "matrices.AskLowerTriangularHandler"),
("diagonal", "matrices.AskDiagonalHandler"),
]
for name, value in _handlers:
register_handler(name, _val_template % value)
known_facts_keys = [
getattr(Q, attr) for attr in Q.__dict__ if not attr.startswith('__')
]
known_facts = And(Implies(Q.real, Q.complex), Implies(Q.real, Q.hermitian),
Equivalent(Q.even, Q.integer & ~Q.odd),
Equivalent(Q.extended_real, Q.real | Q.infinity),
Equivalent(Q.odd, Q.integer & ~Q.even),
Equivalent(Q.prime, Q.integer & Q.positive & ~Q.composite),
Implies(Q.integer, Q.rational),
Implies(Q.imaginary, Q.complex & ~Q.real),
Implies(Q.imaginary, Q.antihermitian),
Implies(Q.antihermitian, ~Q.hermitian),
Equivalent(Q.negative, Q.nonzero & ~Q.positive),
Equivalent(Q.positive, Q.nonzero & ~Q.negative),
Equivalent(Q.rational, Q.real & ~Q.irrational),
Equivalent(Q.real, Q.rational | Q.irrational),
Implies(Q.nonzero, Q.real),
Equivalent(Q.nonzero, Q.positive | Q.negative),
Implies(Q.orthogonal, Q.positive_definite),
def test_count_ops_visual():
ADD, MUL, POW, SIN, COS, EXP, AND, D, G, M = symbols(
'Add Mul Pow sin cos exp And Derivative Integral Sum'.upper())
DIV, SUB, NEG = symbols('DIV SUB NEG')
LT, LE, GT, GE, EQ, NE = symbols('LT LE GT GE EQ NE')
NOT, OR, AND, XOR, IMPLIES, EQUIVALENT, _ITE, BASIC, TUPLE = symbols(
'Not Or And Xor Implies Equivalent ITE Basic Tuple'.upper())
def count(val):
return count_ops(val, visual=True)
assert count(7) is S.Zero
assert count(S(7)) is S.Zero
assert count(-1) == NEG
assert count(-2) == NEG
assert count(S(2) / 3) == DIV
assert count(Rational(2, 3)) == DIV
assert count(pi / 3) == DIV
assert count(-pi / 3) == DIV + NEG
assert count(I - 1) == SUB
assert count(1 - I) == SUB
assert count(1 - 2 * I) == SUB + MUL
assert count(x) is S.Zero
assert count(-x) == NEG
assert count(-2 * x / 3) == NEG + DIV + MUL
assert count(Rational(-2, 3) * x) == NEG + DIV + MUL
assert count(1 / x) == DIV
assert count(1 / (x * y)) == DIV + MUL
assert count(-1 / x) == NEG + DIV
assert count(-2 / x) == NEG + DIV
assert count(x / y) == DIV
assert count(-x / y) == NEG + DIV
assert count(x**2) == POW
assert count(-x**2) == POW + NEG
assert count(-2 * x**2) == POW + MUL + NEG
assert count(x + pi / 3) == ADD + DIV
assert count(x + S.One / 3) == ADD + DIV
assert count(x + Rational(1, 3)) == ADD + DIV
assert count(x + y) == ADD
assert count(x - y) == SUB
assert count(y - x) == SUB
assert count(-1 / (x - y)) == DIV + NEG + SUB
assert count(-1 / (y - x)) == DIV + NEG + SUB
assert count(1 + x**y) == ADD + POW
assert count(1 + x + y) == 2 * ADD
assert count(1 + x + y + z) == 3 * ADD
assert count(1 + x**y + 2 * x * y + y**2) == 3 * ADD + 2 * POW + 2 * MUL
assert count(2 * z + y + x + 1) == 3 * ADD + MUL
assert count(2 * z + y**17 + x + 1) == 3 * ADD + MUL + POW
assert count(2 * z + y**17 + x + sin(x)) == 3 * ADD + POW + MUL + SIN
assert count(2 * z + y**17 + x +
sin(x**2)) == 3 * ADD + MUL + 2 * POW + SIN
assert count(2 * z + y**17 + x + sin(x**2) +
exp(cos(x))) == 4 * ADD + MUL + 2 * POW + EXP + COS + SIN
assert count(Derivative(x, x)) == D
assert count(Integral(x, x) + 2 * x / (1 + x)) == G + DIV + MUL + 2 * ADD
assert count(Sum(x, (x, 1, x + 1)) + 2 * x /
(1 + x)) == M + DIV + MUL + 3 * ADD
assert count(Basic()) is S.Zero
assert count({x + 1: sin(x)}) == ADD + SIN
assert count([x + 1, sin(x) + y, None]) == ADD + SIN + ADD
assert count({x + 1: sin(x), y: cos(x) + 1}) == SIN + COS + 2 * ADD
assert count({}) is S.Zero
assert count([x + 1, sin(x) * y, None]) == SIN + ADD + MUL
assert count([]) is S.Zero
assert count(Basic()) == 0
assert count(Basic(Basic(), Basic(x, x + y))) == ADD + 2 * BASIC
assert count(Basic(x, x + y)) == ADD + BASIC
assert [count(Rel(x, y, op)) for op in '< <= > >= == <> !='.split()
] == [LT, LE, GT, GE, EQ, NE, NE]
assert count(Or(x, y)) == OR
assert count(And(x, y)) == AND
assert count(Or(x, Or(y, And(z, a)))) == AND + OR
assert count(Nor(x, y)) == NOT + OR
assert count(Nand(x, y)) == NOT + AND
assert count(Xor(x, y)) == XOR
assert count(Implies(x, y)) == IMPLIES
assert count(Equivalent(x, y)) == EQUIVALENT
assert count(ITE(x, y, z)) == _ITE
assert count([Or(x, y), And(x, y), Basic(x + y)]) == ADD + AND + BASIC + OR
assert count(Basic(Tuple(x))) == BASIC + TUPLE
#It checks that TUPLE is counted as an operation.
assert count(Eq(x + y, S(2))) == ADD + EQ
("symmetric", "matrices.AskSymmetricHandler"),
("invertible", "matrices.AskInvertibleHandler"),
("orthogonal", "matrices.AskOrthogonalHandler"),
("positive_definite", "matrices.AskPositiveDefiniteHandler"),
("upper_triangular", "matrices.AskUpperTriangularHandler"),
("lower_triangular", "matrices.AskLowerTriangularHandler"),
("diagonal", "matrices.AskDiagonalHandler"),
]
for name, value in _handlers:
register_handler(name, _val_template % value)
known_facts_keys = [getattr(Q, attr) for attr in Q.__dict__
if not attr.startswith('__')]
known_facts = And(
Implies(Q.real, Q.complex),
Implies(Q.real, Q.hermitian),
Equivalent(Q.even, Q.integer & ~Q.odd),
Equivalent(Q.extended_real, Q.real | Q.infinity),
Equivalent(Q.odd, Q.integer & ~Q.even),
Equivalent(Q.prime, Q.integer & Q.positive & ~Q.composite),
Implies(Q.integer, Q.rational),
Implies(Q.imaginary, Q.complex & ~Q.real),
Implies(Q.imaginary, Q.antihermitian),
Implies(Q.antihermitian, ~Q.hermitian),
Equivalent(Q.negative, Q.nonzero & ~Q.positive),
Equivalent(Q.positive, Q.nonzero & ~Q.negative),
Equivalent(Q.rational, Q.real & ~Q.irrational),
Equivalent(Q.real, Q.rational | Q.irrational),
Implies(Q.nonzero, Q.real),
Equivalent(Q.nonzero, Q.positive | Q.negative),
print(Nor(False, True))
print(Nor(False, False))
print(Nor(x, y))
from sympy import true, false
print(True >> False)
print(true >> false)
#implies
from sympy.logic.boolalg import Implies
from sympy import symbols
x, y = symbols('x y')
print(Implies(True, False))
print(Implies(False, False))
print(Implies(True, True))
print(Implies(False, True))
#cnf
from sympy.logic.boolalg import to_cnf
from sympy.abc import A, B, D
print(to_cnf(~(A | B) | D))
print(to_cnf((A | B) & (A | ~A), True))
#dnf
from sympy.logic.boolalg import to_dnf
from sympy.abc import A, B, C
return len(self.d)
def __repr__(self):
return repr(self.d)
fact_registry = ClassFactRegistry()
def register_fact(klass, fact, registry=fact_registry):
registry[klass] |= {fact}
for klass, fact in [
(Mul, Equivalent(Q.zero, AnyArgs(Q.zero))),
(MatMul, Implies(AllArgs(Q.square), Equivalent(Q.invertible, AllArgs(Q.invertible)))),
(Add, Implies(AllArgs(Q.positive), Q.positive)),
(Add, Implies(AllArgs(Q.negative), Q.negative)),
(Mul, Implies(AllArgs(Q.positive), Q.positive)),
(Mul, Implies(AllArgs(Q.commutative), Q.commutative)),
(Mul, Implies(AllArgs(Q.real), Q.commutative)),
(Pow, CustomLambda(lambda power: Implies(Q.real(power.base) &
Q.even(power.exp) & Q.nonnegative(power.exp), Q.nonnegative(power)))),
(Pow, CustomLambda(lambda power: Implies(Q.nonnegative(power.base) & Q.odd(power.exp) & Q.nonnegative(power.exp), Q.nonnegative(power)))),
(Pow, CustomLambda(lambda power: Implies(Q.nonpositive(power.base) & Q.odd(power.exp) & Q.nonnegative(power.exp), Q.nonpositive(power)))),
# This one can still be made easier to read. I think we need basic pattern
# matching, so that we can just write Equivalent(Q.zero(x**y), Q.zero(x) & Q.positive(y))
(Pow, CustomLambda(lambda power: Equivalent(Q.zero(power), Q.zero(power.base) & Q.positive(power.exp)))),
(Integer, CheckIsPrime(Q.prime)),
def _(expr):
# General Case: Odd number of imaginary args implies mul is imaginary(To be implemented)
allargs_imag_or_real = allargs(x, Q.imaginary(x) | Q.real(x), expr)
onearg_imaginary = exactlyonearg(x, Q.imaginary(x), expr)
return Implies(allargs_imag_or_real,
Implies(onearg_imaginary, Q.imaginary(expr)))
def test_sympy__logic__boolalg__Implies():
from sympy.logic.boolalg import Implies
assert _test_args(Implies(x, 2))
def _(expr):
allargs_real = allargs(x, Q.real(x), expr)
onearg_irrational = exactlyonearg(x, Q.irrational(x), expr)
return Implies(allargs_real, Implies(onearg_irrational,
Q.irrational(expr)))
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))
def _(expr):
allargs_square = allargs(x, Q.square(x), expr)
allargs_invertible = allargs(x, Q.invertible(x), expr)
return Implies(allargs_square,
Equivalent(Q.invertible(expr), allargs_invertible))
def test_true_false():
assert true is S.true
assert false is S.false
assert true is not True
assert false is not False
assert true
assert not false
assert true == True
assert false == False
assert not (true == False)
assert not (false == True)
assert not (true == false)
assert hash(true) == hash(True)
assert hash(false) == hash(False)
assert len({true, True}) == len({false, False}) == 1
assert isinstance(true, BooleanAtom)
assert isinstance(false, BooleanAtom)
# We don't want to subclass from bool, because bool subclasses from
# int. But operators like &, |, ^, <<, >>, and ~ act differently on 0 and
# 1 then we want them to on true and false. See the docstrings of the
# various And, Or, etc. functions for examples.
assert not isinstance(true, bool)
assert not isinstance(false, bool)
# Note: using 'is' comparison is important here. We want these to return
# true and false, not True and False
assert Not(true) is false
assert Not(True) is false
assert Not(false) is true
assert Not(False) is true
assert ~true is false
assert ~false is true
for T, F in cartes([True, true], [False, false]):
assert And(T, F) is false
assert And(F, T) is false
assert And(F, F) is false
assert And(T, T) is true
assert And(T, x) == x
assert And(F, x) is false
if not (T is True and F is False):
assert T & F is false
assert F & T is false
if not F is False:
assert F & F is false
if not T is 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 not F is False:
assert F | F is false
if not T is 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 not F is False:
assert F ^ F is false
if not T is 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 not F is False:
assert F >> F is true
assert F << F is true
if not T is 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 get_known_facts():
# We build the facts starting with primitive predicates.
# DO NOT include the predicates in get_composite_predicates()'s keys here!
return And(
# primitive predicates exclude each other
Implies(Q.negative_infinite, ~Q.positive_infinite),
Implies(Q.negative, ~Q.zero & ~Q.positive),
Implies(Q.positive, ~Q.zero),
# build real line and complex plane
Implies(Q.negative | Q.zero | Q.positive, ~Q.imaginary),
Implies(Q.negative | Q.zero | Q.positive | Q.imaginary,
Q.algebraic | Q.transcendental),
# other subsets of complex
Implies(Q.transcendental, ~Q.algebraic),
Implies(Q.irrational, ~Q.rational),
Equivalent(Q.rational | Q.irrational,
Q.negative | Q.zero | Q.positive),
Implies(Q.rational, Q.algebraic),
# integers
Implies(Q.even, ~Q.odd),
Implies(Q.even | Q.odd, Q.rational),
Implies(Q.zero, Q.even),
Implies(Q.composite, ~Q.prime),
Implies(Q.composite | Q.prime, (Q.even | Q.odd) & Q.positive),
Implies(Q.even & Q.positive & ~Q.prime, Q.composite),
# hermitian and antihermitian
Implies(Q.negative | Q.zero | Q.positive, Q.hermitian),
Implies(Q.imaginary, Q.antihermitian),
Implies(Q.zero, Q.hermitian | Q.antihermitian),
# define finity and infinity, and build extended real line
Implies(Q.infinite, ~Q.finite),
Implies(Q.algebraic | Q.transcendental, Q.finite),
Implies(Q.negative_infinite | Q.positive_infinite, Q.infinite),
# commutativity
Implies(Q.finite | Q.infinite, Q.commutative),
# matrices
Implies(Q.orthogonal, Q.positive_definite),
Implies(Q.orthogonal, Q.unitary),
Implies(Q.unitary & Q.real_elements, Q.orthogonal),
Implies(Q.unitary, Q.normal),
Implies(Q.unitary, Q.invertible),
Implies(Q.normal, Q.square),
Implies(Q.diagonal, Q.normal),
Implies(Q.positive_definite, Q.invertible),
Implies(Q.diagonal, Q.upper_triangular),
Implies(Q.diagonal, Q.lower_triangular),
Implies(Q.lower_triangular, Q.triangular),
Implies(Q.upper_triangular, Q.triangular),
Implies(Q.triangular, Q.upper_triangular | Q.lower_triangular),
Implies(Q.upper_triangular & Q.lower_triangular, Q.diagonal),
Implies(Q.diagonal, Q.symmetric),
Implies(Q.unit_triangular, Q.triangular),
Implies(Q.invertible, Q.fullrank),
Implies(Q.invertible, Q.square),
Implies(Q.symmetric, Q.square),
Implies(Q.fullrank & Q.square, Q.invertible),
Equivalent(Q.invertible, ~Q.singular),
Implies(Q.integer_elements, Q.real_elements),
Implies(Q.real_elements, Q.complex_elements),
)
def test_simplification():
"""
Test working of simplification methods.
"""
set1 = [[0, 0, 1], [0, 1, 1], [1, 0, 0], [1, 1, 0]]
set2 = [[0, 0, 0], [0, 1, 0], [1, 0, 1], [1, 1, 1]]
assert SOPform([x, y, z], set1) == Or(And(Not(x), z), And(Not(z), x))
assert Not(SOPform([x, y, z], set2)) == \
Not(Or(And(Not(x), Not(z)), And(x, z)))
assert POSform([x, y, z], set1 + set2) is true
assert SOPform([x, y, z], set1 + set2) is true
assert SOPform([Dummy(), Dummy(), Dummy()], set1 + set2) is true
minterms = [[0, 0, 0, 1], [0, 0, 1, 1], [0, 1, 1, 1], [1, 0, 1, 1],
[1, 1, 1, 1]]
dontcares = [[0, 0, 0, 0], [0, 0, 1, 0], [0, 1, 0, 1]]
assert (
SOPform([w, x, y, z], minterms, dontcares) ==
Or(And(Not(w), z), And(y, z)))
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(Not(w), z), And(y, z)))
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(Not(w), z), And(y, z)))
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(Not(w), z), And(y, z)))
assert POSform([w, x, y, z], minterms, dontcares) == And(Or(Not(w), y), z)
minterms = [{y: 1, z: 1}, 1]
dontcares = [[0, 0, 0, 0]]
minterms = [[0, 0, 0]]
raises(ValueError, lambda: SOPform([w, x, y, z], minterms))
raises(ValueError, lambda: POSform([w, x, y, z], minterms))
raises(TypeError, lambda: POSform([w, x, y, z], ["abcdefg"]))
# test simplification
ans = And(A, Or(B, C))
assert simplify_logic(A & (B | C)) == ans
assert simplify_logic((A & B) | (A & C)) == ans
assert simplify_logic(Implies(A, B)) == Or(Not(A), B)
assert simplify_logic(Equivalent(A, B)) == \
Or(And(A, B), And(Not(A), Not(B)))
assert simplify_logic(And(Equality(A, 2), C)) == And(Equality(A, 2), C)
assert simplify_logic(And(Equality(A, 2), A)) is S.false
assert simplify_logic(And(Equality(A, 2), A)) == And(Equality(A, 2), A)
assert simplify_logic(And(Equality(A, B), C)) == And(Equality(A, B), C)
assert simplify_logic(Or(And(Equality(A, 3), B), And(Equality(A, 3), C))) \
== And(Equality(A, 3), Or(B, C))
b = (~x & ~y & ~z) | (~x & ~y & z)
e = And(A, b)
assert simplify_logic(e) == A & ~x & ~y
raises(ValueError, lambda: simplify_logic(A & (B | C), form='blabla'))
# Check that expressions with nine variables or more are not simplified
# (without the force-flag)
a, b, c, d, e, f, g, h, j = symbols('a b c d e f g h j')
expr = a & b & c & d & e & f & g & h & j | \
a & b & c & d & e & f & g & h & ~j
# This expression can be simplified to get rid of the j variables
assert simplify_logic(expr) == expr
# check input
ans = SOPform([x, y], [[1, 0]])
assert SOPform([x, y], [[1, 0]]) == ans
assert POSform([x, y], [[1, 0]]) == ans
raises(ValueError, lambda: SOPform([x], [[1]], [[1]]))
assert SOPform([x], [[1]], [[0]]) is true
assert SOPform([x], [[0]], [[1]]) is true
assert SOPform([x], [], []) is false
raises(ValueError, lambda: POSform([x], [[1]], [[1]]))
assert POSform([x], [[1]], [[0]]) is true
assert POSform([x], [[0]], [[1]]) is true
assert POSform([x], [], []) is false
# check working of simplify
assert simplify((A & B) | (A & C)) == And(A, Or(B, C))
assert simplify(And(x, Not(x))) == False
assert simplify(Or(x, Not(x))) == True
assert simplify(And(Eq(x, 0), Eq(x, y))) == And(Eq(x, 0), Eq(y, 0))
assert And(Eq(x - 1, 0), Eq(x, y)).simplify() == And(Eq(x, 1), Eq(y, 1))
assert And(Ne(x - 1, 0), Ne(x, y)).simplify() == And(Ne(x, 1), Ne(x, y))
assert And(Eq(x - 1, 0), Ne(x, y)).simplify() == And(Eq(x, 1), Ne(y, 1))
assert And(Eq(x - 1, 0), Eq(x, z + y), Eq(y + x, 0)).simplify(
) == And(Eq(x, 1), Eq(y, -1), Eq(z, 2))
assert And(Eq(x - 1, 0), Eq(x + 2, 3)).simplify() == Eq(x, 1)
assert And(Ne(x - 1, 0), Ne(x + 2, 3)).simplify() == Ne(x, 1)
assert And(Eq(x - 1, 0), Eq(x + 2, 2)).simplify() == False
assert And(Ne(x - 1, 0), Ne(x + 2, 2)).simplify(
) == And(Ne(x, 1), Ne(x, 0))
def test_implies_intuitive(self):
A, B = self.alpha_symbols[:2]
expr = Implies(A, B)
model = mental_model_builder(expr, Insight.INTUITIVE)
npt.assert_allclose(model.model, np.array([[POS_VAL, POS_VAL]]))
