def test_search_complex():
# (~x|z) & (~x|~z|~y) & (~z|w) & (~w|~y) (lec3, slide 18)
# (~x1 | x2) & (~x1 | ~x2 | ~x3) & (~x2 | x4) & (~x4| ~x3)
x1_var = Variable('x1')
x2_var = Variable('x2')
x3_var = Variable('x3')
x4_var = Variable('x4')
x5_var = Variable('x5')
x6_var = Variable('x6')
x1 = Literal(x1_var, negated=False)
not_x1 = Literal(x1_var, negated=True)
x2 = Literal(x2_var, negated=False)
not_x2 = Literal(x2_var, negated=True)
x3 = Literal(x3_var, negated=False)
not_x3 = Literal(x3_var, negated=True)
x4 = Literal(x4_var, negated=False)
not_x4 = Literal(x4_var, negated=True)
x5 = Literal(x5_var, negated=False)
not_x5 = Literal(x5_var, negated=True)
x6 = Literal(x6_var, negated=False)
not_x6 = Literal(x6_var, negated=True)
# (~x1 | x2) & (~x1 | ~x2 | ~x3) & (~x2 | x4) & (~x4| ~x3)
clauses = [[not_x1, x2], [not_x1, not_x2, not_x3], [not_x2, x4],
[not_x4, not_x3], [x5, x6], [not_x5, not_x6]]
cnf = CnfFormula(clauses)
cnf = preprocess(cnf)
dpll = DPLL(cnf)
search_result = dpll.search()
assert search_result
def solve(self) -> bool:
dpll_algorithm = DPLL(self.sat_formula, propagate_helper=self.propagate, conflict_helper=self.conflict)
# Solve sat formula
is_sat = dpll_algorithm.search()
# The search is infeasible
if not is_sat:
return False
return True
def solve(self) -> Tuple[bool, Optional[Dict[str, bool]]]:
from sat_solver.preprocessor import preprocess_from_sat
cnf_formula = preprocess_from_sat(self.sat_formula)
dpll_algorithm = DPLL(cnf_formula,
propagate_helper=self.propagate,
conflict_helper=self.conflict)
# Solve sat formula
is_sat = dpll_algorithm.search()
# Sat formula is unsat hence, smt formula is ussat
if not is_sat:
return False, None
partial_assignment = dpll_algorithm.get_partial_assignment()
assignment = self.transfer_assignment(partial_assignment)
return self.satisfied(partial_assignment), assignment
def test_search_complex_unsat():
variables = [Variable('TEMP')
] + [Variable('x{}'.format(i + 1)) for i in range(10)]
pos_l = [Literal(v, negated=False) for v in variables]
neg_l = [Literal(v, negated=True) for v in variables]
# x1 = T, x2 = F, x3 =
# x3 != x2 /\ x1 != x2 /\ (!x1 \/ x2 \/ !x3) /\ (x1 \/ !x2 \/ x3)
clauses = [[pos_l[1], pos_l[2]], [neg_l[1], neg_l[2]],
[pos_l[3], pos_l[2]], [neg_l[3], neg_l[2]],
[neg_l[1], pos_l[2], neg_l[3]], [pos_l[3], neg_l[2], pos_l[1]]]
cnf = CnfFormula(clauses)
cnf = preprocess(cnf)
dpll = DPLL(cnf)
search_result = dpll.search()
# print(dpll.get_assignment())
assert not search_result
def test_search_simple_unsat():
# (x1|~x2) | (~x1 | x2)
x1_var = Variable('x1')
x2_var = Variable('x2')
# x3_var = Variable('x3')
x1 = Literal(x1_var, negated=False)
not_x1 = Literal(x1_var, negated=True)
x2 = Literal(x2_var, negated=False)
not_x2 = Literal(x2_var, negated=True)
clauses = [[x1], [x2], [not_x1, not_x2]]
# literal_to_clauses = {x1: {0}, x2: {0}, x3: {0}} #not_x1: {2}, not_x2: {0}
cnf = CnfFormula(clauses)
cnf = preprocess(cnf)
dpll = DPLL(cnf)
search_result = dpll.search()
assert not search_result
def test_search_simple():
# (x1|x2|~x3) | (x3 | ~x2)
x1_var = Variable('x1')
x2_var = Variable('x2')
x3_var = Variable('x3')
x1 = Literal(x1_var, negated=False)
not_x1 = Literal(x1_var, negated=True)
x2 = Literal(x2_var, negated=False)
not_x2 = Literal(x2_var, negated=True)
x3 = Literal(x3_var, negated=False)
not_x3 = Literal(x3_var, negated=True)
clauses = [[x1, x2, not_x3], [x3, not_x2]]
cnf = CnfFormula(clauses)
cnf = preprocess(cnf)
dpll = DPLL(cnf)
search_result = dpll.search()
assert search_result
def test_multi_level_deduction_sat():
x1_var = Variable('x1')
x2_var = Variable('x2')
x3_var = Variable('x3')
x1 = Literal(x1_var, negated=False)
not_x1 = Literal(x1_var, negated=True)
x2 = Literal(x2_var, negated=False)
not_x2 = Literal(x2_var, negated=True)
x3 = Literal(x3_var, negated=False)
not_x3 = Literal(x3_var, negated=True)
clauses = [[x1], [x3, x2], [not_x2, not_x3, not_x1]]
cnf = CnfFormula(clauses)
cnf = preprocess(cnf)
dpll = DPLL(cnf)
search_result = dpll.search()
assert search_result
def test_multi_level_conflict_sat():
vars = [Variable('x{}'.format(i + 1)) for i in range(8)]
pos_l = [None] + [Literal(v, negated=False) for v in vars]
neg_l = [None] + [Literal(v, negated=True) for v in vars]
c1 = [pos_l[2], pos_l[3]]
# c2 = [pos_l[1], pos_l[4], neg_l[8]]
c3 = [neg_l[3], neg_l[4]]
c4 = [neg_l[4], neg_l[2], neg_l[1]]
c5 = [neg_l[6], neg_l[5], pos_l[4]]
c6 = [pos_l[7], pos_l[5]]
c7 = [neg_l[8], pos_l[7], pos_l[6]]
conflict = [c3, c4, c5, c6, c7, c1] # c2,
# If we implement pure_literal will need to change this
# this is just to make sure the order decisions will be: x1=True, x2=True, x3=True, the conflict is because x1
n_temps = 4
temp_literals = [
Literal(Variable('x1_temp{}'.format(idx)), negated=False)
for idx in range(n_temps)
]
x1_clauses = [[pos_l[1], l] for l in temp_literals]
temp_literals = [
Literal(Variable('x8_temp{}'.format(idx)), negated=False)
for idx in range(n_temps)
]
x8_clauses = [[pos_l[8], l] for l in temp_literals[:-1]]
temp_literals = [
Literal(Variable('x7_temp{}'.format(idx)), negated=False)
for idx in range(n_temps)
]
x7_clauses = [[neg_l[7], l] for l in temp_literals[:-2]]
clauses = x1_clauses + x8_clauses + x7_clauses + conflict
cnf = CnfFormula(clauses)
cnf = preprocess(cnf)
dpll = DPLL(cnf)
search_result = dpll.search()
assert search_result
def perform_test(clauses: List[List[Literal]], debug=False):
z3_time_start = timer()
z3_res = get_z3_result(clauses, debug)
z3_time_end = timer()
our_time_start = timer()
cnf = CnfFormula(clauses)
cnf = preprocess(cnf)
dpll = DPLL(cnf)
search_result = dpll.search()
if debug:
print(dpll.get_full_assignment())
our_time_end = timer()
assert search_result == z3_res, "Our: {}, Z3: {}".format(
search_result, z3_res)
res_str = 'Sat ' if search_result else 'UNSAT '
all_vars = set([lit.variable for clause in clauses for lit in clause])
res_str += "#var: {}, #clauses: {} #per_clause: {} ".format(
len(all_vars), len(clauses), len(clauses[0]))
res_str += "Time(sec): Our {:0.2f}, z3: {:0.2f}".format(
our_time_end - our_time_start, z3_time_end - z3_time_start)
print(res_str)
def get_result(query: str):
sat_formula = SatFormula.from_str(query)
formula = preprocess_from_sat(sat_formula)
dpll = DPLL(formula)
res = dpll.search()
return res
from lp_solver.lp_program import LpProgram
from lp_solver.unbounded_exception import UnboundedException, InfeasibleException
from lp_solver.lp_theory import LpTheory
if __name__ == "__main__":
if len(sys.argv) < 3:
print("execution instructions [SAT|SMT|LP] [query string]")
exit(1)
q = sys.argv[2]
if sys.argv[1].lower() == 'sat':
sat = SatFormula.from_str(q)
formula = preprocess_from_sat(sat)
dpll = DPLL(formula)
res = dpll.search()
print(f"Got {'SAT' if res else 'UNSAT'} for query\n{q}")
# optional to retrieve the assignment
if res:
assignment = dpll.get_full_assignment()
all_variables = set(l.variable for l in sat.get_literals())
actual_assignments = map(lambda k: (k, assignment[k]),
all_variables)
pprint(dict(actual_assignments))
if sys.argv[1].lower() == 'smt':
smt_query = Formula.from_str(q)
res, model = smt_query.solve()
print(f"Got {'SAT' if res else 'UNSAT'} for query\n{q}")
if sys.argv[1].lower() == 'lp':
if len(sys.argv) < 4: