def unify(x, y, theta):
if theta is False:
return False
if (x == y):
return theta
if (Fact.is_variable(x)):
return unifyVar(x, y, theta)
elif (Fact.is_variable(y)):
return unifyVar(y, x, theta)
elif (Fact.is_fact(x) and Fact.is_fact(y)):
return unify(x.get_args(), y.get_args(),
unify(x.get_op(), y.get_op(), theta))
elif (Fact.is_list(x) and Fact.is_list(y)):
return unify(x[1:], y[1:], unify(x[0], y[0], theta))
return False
def resolution_search(kb, goal):
consts = kb.getAllConsts()
args = goal.get_args()
var_loc = []
for i in range(len(args)):
if Fact.is_variable(args[i]):
var_loc.append(i)
if len(var_loc) == 0:
return resolution(kb, goal)
theta = [list() for i in range(len(var_loc))]
newGoal = goal.copy()
if set_variable(var_loc, 0, kb, newGoal, consts, theta) is not False:
string = str()
for i in range(len(theta[0])):
line = "{"
for j in range(len(var_loc)):
line += "{} = {}, ".format(goal.get_args()[var_loc[j]],
theta[j][i])
string += line.rstrip(", ") + "}; "
return string.rstrip("; ")
return False
