def ask(self, query):
"""Checks if the query is true given the set of clauses.
Examples
========
>>> from sympy.logic.inference import PropKB
>>> from sympy.abc import x, y
>>> l = PropKB()
>>> l.tell(x & ~y)
>>> l.ask(x)
True
>>> l.ask(y)
False
"""
if len(self.clauses) == 0:
return False
from sympy.logic.algorithms.dpll import dpll
query_conjuncts = self.clauses[:]
query_conjuncts.extend(conjuncts(to_cnf(query)))
s = set()
for q in query_conjuncts:
s = s.union(q.atoms(C.Symbol))
return bool(dpll(query_conjuncts, list(s), {}))
def ask(self, query):
"""TODO: examples"""
if len(self.clauses) == 0: return False
query_conjuncts = self.clauses[:]
query_conjuncts.extend(conjuncts(to_cnf(query)))
s = set()
for q in query_conjuncts:
s = s.union(q.atoms(Symbol))
return bool(dpll(query_conjuncts, list(s), {}))
def ask(self, query):
"""TODO: examples"""
if len(self.clauses) == 0: return False
from sympy.logic.algorithms.dpll import dpll
query_conjuncts = self.clauses[:]
query_conjuncts.extend(conjuncts(to_cnf(query)))
s = set()
for q in query_conjuncts:
s = s.union(q.atoms(C.Symbol))
return bool(dpll(query_conjuncts, list(s), {}))
def ask(self, query):
"""TODO: examples"""
if len(self.clauses) == 0: return False
from sympy.logic.algorithms.dpll import dpll
query_conjuncts = self.clauses[:]
query_conjuncts.extend(conjuncts(to_cnf(query)))
s = set()
for q in query_conjuncts:
s = s.union(q.atoms(C.Symbol))
return bool(dpll(query_conjuncts, list(s), {}))
def ask(self, query):
"""Checks if the query is true given the set of clauses.
Examples
========
>>> from sympy.logic.inference import PropKB
>>> from sympy.abc import x, y
>>> l = PropKB()
>>> l.tell(x & ~y)
>>> l.ask(x)
True
>>> l.ask(y)
False
"""
if len(self.clauses) == 0: return False
from sympy.logic.algorithms.dpll import dpll
query_conjuncts = self.clauses[:]
query_conjuncts.extend(conjuncts(to_cnf(query)))
s = set()
for q in query_conjuncts:
s = s.union(q.atoms(C.Symbol))
return bool(dpll(query_conjuncts, list(s), {}))
def test_dpll():
"""This is also tested in test_dimacs"""
A, B, C = symbols('A,B,C')
assert dpll([A | B], [A, B], {A: True, B: True}) == {A: True, B: True}
def test_dpll():
"""This is also tested in test_dimacs"""
A, B, C = symbols('A,B,C')
assert dpll([A | B], [A, B], {A: True, B: True}) == {A: True, B: True}
