class SATModerno_fromFormula:
def __init__(self):
self.cnf = CNF()
def runPySAT_fromFormula(self, formula):
list_clauses = []
relationAndClauses = self.cnf.formulaToCNFClauses(formula)
clauses = list(relationAndClauses.get("clauses"))
glucose = Glucose3()
for clause in clauses:
list_clauses.append(list(clause))
glucose.append_formula(list_clauses)
return glucose.solve()
class DPLL:
def __init__(self):
self.cnf = CNF()
def runFromFile(self, filePath):
clauses = self.cnf.readCNFFile(filePath)
return self.__dpllRecursion(clauses, set())
def runFromFormula(self, formula):
relationAndClauses = self.cnf.formulaToCNFClauses(formula)
relation = relationAndClauses.get("relation")
clauses = relationAndClauses.get("clauses")
result = self.__dpllRecursion(clauses, set())
if not result:
return result
valuation = dict()
for literal in result:
if literal > 0:
valuation[relation.get(literal)] = True
else:
valuation[relation.get(abs(literal))] = False
return valuation
def __dpllRecursion(self, clauses, valuation):
clauses, valuation = self.__unitPropagation(clauses, valuation)
if len(clauses) == 0:
return valuation
if self.__hasEmptyClause(clauses):
return False
literal = self.__getLiteral(clauses)
clausesFirstCase = clauses.union({frozenset([literal])})
clausesSecondCase = clauses.union({frozenset([literal * -1])})
result = self.__dpllRecursion(clausesFirstCase, valuation)
if result:
return result
return self.__dpllRecursion(clausesSecondCase, valuation)
def __unitPropagation(self, clauses, valuation):
unitaryClause = self.__getUnitaryClause(clauses)
while unitaryClause is not None:
clauses.remove(unitaryClause)
valuation = valuation.union(unitaryClause)
literal = list(unitaryClause)[0]
toRemove = set()
newCalsues = set()
for clause in clauses:
if literal in clause:
toRemove.add(clause)
continue
inversedLiteral = literal * -1
if inversedLiteral in clause:
# print(literal)
newClause = clause.difference({inversedLiteral})
# print(clause, newClause)
newCalsues.add(frozenset(newClause))
if len(newClause) == 0:
clauses = clauses.difference(toRemove).union(
newCalsues)
return clauses, valuation
clauses = clauses.difference(toRemove).union(newCalsues)
toRemove.clear()
newCalsues.clear()
unitaryClause = self.__getUnitaryClause(clauses)
return clauses, valuation
def __getUnitaryClause(self, clauses):
for clause in clauses:
if len(clause) == 1:
return clause
return None
def __hasEmptyClause(self, clauses):
for clause in clauses:
if len(clause) == 0:
return True
return False
def __getLiteral(self, clauses):
smaller = None
for clause in clauses:
if smaller is None:
smaller = clause
continue
if len(clause) < len(smaller):
smaller = clause
return list(smaller)[0]
class Resolution:
def __init__(self):
self.cnf = CNF()
def runFromFile(self, filePath):
clauses = self.cnf.readCNFFile(filePath)
return self.__resolutionMethod(clauses)
def runFromFormula(self, formula):
clause = self.cnf.formulaToCNFClauses(formula)
return self.__resolutionMethod(clauses)
def __resolutionMethod(self, clauses):
clauses = self.__removeTrivialClauses(clauses)
for currentClause in clauses:
for clause in clauses:
if currentClause == clause:
continue
trivialLiteral = self.__getTrivialLiteral(
currentClause, clause)
if trivialLiteral:
currentClauseCopy = set(currentClause)
currentClauseCopy.remove(trivialLiteral)
clauseCopy = set(clause)
clauseCopy.remove((trivialLiteral * -1))
newClause = frozenset(currentClauseCopy.union(clauseCopy))
if not len(newClause):
return False
setClauses = set(clauses)
setClauses.add(newClause)
clauses = list(setClauses)
if len(clauses) > 0:
return set(clauses)
return True
def __removeTrivialClauses(self, clauses):
for clause in clauses:
if self.__isTivialClause(clause):
clauses.remove(clause)
return clauses
def __isTrivialClause(self, clause):
for literal in clause:
if (literal * -1) in clause:
return True
return False
def __getTrivialLiteral(self, currentClause, clause):
trivialLiteral = None
for literal in currentClause:
if (literal * -1) in clause:
if trivialLiteral is None:
trivialLiteral = literal
else:
trivialLiteral = None
break
return trivialLiteral
