def test_convert_to_cnf(self):
statement = Not(Iff(Symbol("a"), Symbol("c")))
statement = converter.convert_formula(statement)
a_symbol = Symbol("a")
c_symbol = Symbol("c")
expected = And(
And(Or(c_symbol, a_symbol), Or(Not(a_symbol), a_symbol)),
And(Or(c_symbol, Not(c_symbol)), Or(Not(a_symbol), Not(c_symbol))))
self.assertEqual(expected, statement)
def _add_statement(statement, add_to_list):
"""
:param statement:
:param add_to_list:
:param additional: additional operator to apply onto statement
:return:
"""
statement = parser.parse(statement)
statement = converter.convert_formula(statement)
add_to_list.append(statement)
def test_cnf_converter_symbol(self):
statement = Symbol("a")
statement = converter.convert_formula(statement)
expected = Symbol("a")
self.assertEqual(expected, statement)
def test_cnf_error_on_string(self):
with self.assertRaises(TypeError):
converter.convert_formula("invalid")
def test_convert_to_cnf_2(self):
statement = parser.parse("forall(x,if(A(x),and(B(x),C(x))))")
statement = converter.convert_formula(statement)
expected = "((B(Herbrand1) | ~A(Herbrand1)) & (C(Herbrand1) | ~A(Herbrand1)))"
self.assertEqual(expected, str(statement))
def test_cnf_negation(self):
statement = Not(Not(And(Symbol("a"), Symbol("b"))))
statement = converter.convert_formula(statement)
expected = And(Symbol("a"), Symbol("b"))
self.assertEqual(expected, statement)
def test_cnf_or_distribution(self):
statement = Or(And(Symbol("a"), Symbol("b")), Symbol("c"))
statement = converter.convert_formula(statement)
expected = And(Or(Symbol("a"), Symbol("c")),
Or(Symbol("b"), Symbol("c")))
self.assertEqual(expected, statement)
def test_cnf_not_distribution(self):
statement = Not(And(Symbol("a"), Symbol("b")))
statement = converter.convert_formula(statement)
expected = Or(Not(Symbol("a")), Not(Symbol("b")))
self.assertEqual(expected, statement)
def test_cnf_converter_equiv(self):
statement = Iff(Symbol("a"), Symbol("b"))
statement = converter.convert_formula(statement)
expected = And(Or(Not(Symbol("a")), Symbol("b")),
Or(Not(Symbol("b")), Symbol("a")))
self.assertEqual(expected, statement)