Examples with TautologyPredicate org.logicng.predicates.satisfiability.TautologyPredicate used on opensource projects

Example 1 with TautologyPredicate

use of org.logicng.predicates.satisfiability.TautologyPredicate in project LogicNG by logic-ng.

the class BDDReorderingTest method verifyBddConsistency.

private boolean verifyBddConsistency(final FormulaFactory f, final Formula f1, final BDD bdd, final BigInteger modelCount) {
    final BDDVerification verification = new BDDVerification(bdd.underlyingKernel());
    if (!verification.verify(bdd.index())) {
        return false;
    }
    final long nodes = verification.verifyTree(bdd.index());
    if (nodes < 0) {
        return false;
    }
    this.stats.newBddSize(nodes);
    if (modelCount != null && !modelCount.equals(bdd.modelCount())) {
        System.out.println("Nodecount changed!");
        return false;
    }
    if (modelCount == null && !f.equivalence(f1, bdd.cnf()).holds(new TautologyPredicate(f))) {
        System.out.println("Not equal");
        return false;
    }
    return true;
}

Example 2 with TautologyPredicate

use of org.logicng.predicates.satisfiability.TautologyPredicate in project LogicNG by logic-ng.

the class FormulaBDDTest method testBDDGeneration.

@Test
public void testBDDGeneration() throws ParserException {
    final FormulaFactory f = new FormulaFactory();
    final PseudoBooleanParser p = new PseudoBooleanParser(f);
    final Formula formula = p.parse("(A => ~B) & ((A & C) | (D & ~C)) & (A | Y | X) & (Y <=> (X | (W + A + F < 1)))");
    final BDD bddNoOrder = formula.bdd();
    final BDD bddBfs = formula.bdd(VariableOrdering.BFS);
    final BDD bddDfs = formula.bdd(VariableOrdering.DFS);
    final BDD bddMin2Max = formula.bdd(VariableOrdering.MIN2MAX);
    final BDD bddMax2Min = formula.bdd(VariableOrdering.MAX2MIN);
    assertThat(bddNoOrder.nodeCount()).isEqualTo(13);
    assertThat(bddBfs.nodeCount()).isEqualTo(14);
    assertThat(bddDfs.nodeCount()).isEqualTo(13);
    assertThat(bddMin2Max.nodeCount()).isEqualTo(14);
    assertThat(bddMax2Min.nodeCount()).isEqualTo(22);
    final TautologyPredicate tautology = new TautologyPredicate(f);
    assertThat(f.equivalence(bddNoOrder.cnf(), formula).holds(tautology)).isTrue();
    assertThat(f.equivalence(bddBfs.cnf(), formula).holds(tautology)).isTrue();
    assertThat(f.equivalence(bddDfs.cnf(), formula).holds(tautology)).isTrue();
    assertThat(f.equivalence(bddMin2Max.cnf(), formula).holds(tautology)).isTrue();
    assertThat(f.equivalence(bddMax2Min.cnf(), formula).holds(tautology)).isTrue();
}

Example 3 with TautologyPredicate

use of org.logicng.predicates.satisfiability.TautologyPredicate in project LogicNG by logic-ng.

the class PlaistedGreenbaumTransformationSolverTest method computeAndVerify.

private static void computeAndVerify(final Formula formula) {
    final FormulaFactory f = formula.factory();
    final SATSolver solver = MiniSat.miniSat(f, MiniSatConfig.builder().cnfMethod(MiniSatConfig.CNFMethod.FULL_PG_ON_SOLVER).auxiliaryVariablesInModels(false).build());
    solver.add(formula);
    final List<Assignment> models = solver.enumerateAllModels();
    final Formula dnf = f.or(models.stream().map(model -> f.and(model.literals())).collect(Collectors.toList()));
    assertThat(f.equivalence(formula, dnf).holds(new TautologyPredicate(f))).isTrue();
}

Example 4 with TautologyPredicate

use of org.logicng.predicates.satisfiability.TautologyPredicate in project LogicNG by logic-ng.

the class DNFSubsumptionTest method testEvenLargerFormulas.

@Test
public void testEvenLargerFormulas() throws IOException, ParserException {
    final FormulaFactory f = new FormulaFactory();
    final Formula formula = FormulaReader.readPseudoBooleanFormula("src/test/resources/formulas/small_formulas.txt", f);
    // test only first 10 formulas
    int count = 10;
    for (final Formula op : formula) {
        if (count == 0) {
            break;
        }
        final Formula dnf = op.transform(new DNFFactorization());
        final Formula subsumed = dnf.transform(new DNFSubsumption());
        assertThat(f.equivalence(dnf, subsumed).holds(new TautologyPredicate(f))).isTrue();
        assertThat(dnf.numberOfOperands() > subsumed.numberOfOperands()).isTrue();
        count--;
    }
}

Example 5 with TautologyPredicate

use of org.logicng.predicates.satisfiability.TautologyPredicate in project LogicNG by logic-ng.

the class QuineMcCluskeyTest method testLarge1.

@Test
public void testLarge1() throws ParserException {
    final FormulaFactory f = new FormulaFactory();
    final PropositionalParser p = new PropositionalParser(f);
    final Formula formula = p.parse("A => B & ~((D | E | I | J) & ~K) & L");
    final Formula dnf = QuineMcCluskeyAlgorithm.compute(formula);
    assertThat(dnf.holds(DNFPredicate.get())).isTrue();
    assertThat(f.equivalence(formula, dnf).holds(new TautologyPredicate(f))).isTrue();
}