def test_mrs_robinson(self):
f1 = Function("f", [Variable("X")])
f2 = Function("f", [Variable("Y")])
sigma = u.mrs_robinson(f1, f2)
f1 = u.substitute(f1, sigma)
f2 = u.substitute(f2, sigma)
self.assertTrue(f1 == f2)
def test_mrs_robinson(self):
f1 = Function("f",[Variable("X")])
f2 = Function("f",[Variable("Y")])
sigma = u.mrs_robinson(f1,f2)
f1 = u.substitute(f1,sigma)
f2 = u.substitute(f2,sigma)
self.assertTrue(f1==f2)
def resolute(disj_a, disj_b):
result_set = set([])
temp = deepcopy(disj_a), deepcopy(disj_b)
if temp in memo:
return memo[temp]
for formula in disj_a:
for other_formula in disj_b:
if type(other_formula) == f.UnaryOperator and type(
formula) == f.Relation:
# if repr(formula) == "q(v1)":
# pdb.set_trace()
sigma = u.mrs_robinson(other_formula.term, formula)
list_disj_a = []
list_disj_b = []
# simple case resolution possible
if other_formula.term == formula:
list_disj_a = list(disj_a)
list_disj_b = list(disj_b)
list_disj_a.remove(formula)
list_disj_b.remove(other_formula)
# difficult case resolution with unification possible
elif sigma:
list_disj_a = [
s_wrapper(x, sigma) for x in disj_a if not x is formula
]
list_disj_b = [
s_wrapper(x, sigma) for x in disj_b
if not x is other_formula
]
else:
print("Can not resolute", disj_a, "with", disj_b)
continue
resolvente = Disjunction(list_disj_a + list_disj_b)
free_vars = disj_a.free_vars.union(disj_b.free_vars)
#sig = {}
#for var in free_vars:
# sig[var] =next(gen_free())
#resolvente = Disjunction([ s_wrapper(x, sig) for x in resolvente ])
#resolvente.free_vars = set(sig.values())
#if repr(list_disj_a) == "[~r(v4)]":
# pdb.set_trace()
if not is_tautology(resolvente):
print("sigma is ", sigma)
print("Resoluting", disj_a, "with", disj_b, "to",
resolvente)
result_set.add(resolvente)
else:
print("Result is tautology (", disj_a, disj_a, ")",
resolvente)
memo[temp] = result_set
return result_set
