Examples with Literal org.logicng.formulas.Literal used on opensource projects

Example 86 with Literal

use of org.logicng.formulas.Literal in project LogicNG by logic-ng.

the class LiteralProfileTest method testNot.

@Test
public void testNot() throws ParserException {
    final Map<Literal, Integer> expected = new HashMap<>();
    expected.put(this.f2.variable("a"), 2);
    expected.put(this.f2.variable("b"), 1);
    expected.put(this.f2.variable("c"), 1);
    expected.put(this.f2.literal("b", false), 1);
    expected.put(this.f2.literal("c", false), 2);
    final PropositionalParser p = new PropositionalParser(this.f);
    final Formula formula = p.parse("~(a & (b | c) & ((~b | ~c) => (~c & a)))");
    assertThat(formula.apply(this.litProfile, true)).isEqualTo(expected);
    assertThat(formula.apply(this.litProfile, false)).isEqualTo(expected);
}

Example 87 with Literal

use of org.logicng.formulas.Literal in project LogicNG by logic-ng.

the class MinimumPrimeImplicantTest method isPrimeImplicant.

private void isPrimeImplicant(final Formula formula, final SortedSet<Literal> pi) {
    assertThat(this.f.implication(this.f.and(pi), formula).holds(new TautologyPredicate(this.f))).isTrue();
    for (final Literal literal : pi) {
        final TreeSet<Literal> newSet = new TreeSet<>(pi);
        newSet.remove(literal);
        if (!newSet.isEmpty()) {
            assertThat(this.f.implication(this.f.and(newSet), formula).holds(new TautologyPredicate(this.f))).isFalse();
        }
    }
}

Example 88 with Literal

use of org.logicng.formulas.Literal in project LogicNG by logic-ng.

the class MinimumPrimeImplicantTest method testSimpleCases.

@Test
public void testSimpleCases() throws ParserException {
    Formula formula = this.f.parse("a");
    SortedSet<Literal> pi = formula.apply(MinimumPrimeImplicantFunction.get());
    assertThat(pi).hasSize(1);
    isPrimeImplicant(formula, pi);
    formula = this.f.parse("a | b | c");
    pi = formula.apply(MinimumPrimeImplicantFunction.get());
    assertThat(pi).hasSize(1);
    isPrimeImplicant(formula, pi);
    formula = this.f.parse("a & b & (~a|~b)");
    pi = formula.apply(MinimumPrimeImplicantFunction.get());
    assertThat(pi).isNull();
    formula = this.f.parse("a & b & c");
    pi = formula.apply(MinimumPrimeImplicantFunction.get());
    assertThat(pi).hasSize(3);
    isPrimeImplicant(formula, pi);
    formula = this.f.parse("a | b | ~c => e & d & f");
    pi = formula.apply(MinimumPrimeImplicantFunction.get());
    assertThat(pi).hasSize(3);
    isPrimeImplicant(formula, pi);
    formula = this.f.parse("a | b | ~c <=> e & d & f");
    pi = formula.apply(MinimumPrimeImplicantFunction.get());
    assertThat(pi).hasSize(4);
    isPrimeImplicant(formula, pi);
    formula = this.f.parse("(a | b | ~c <=> e & d & f) | (a | b | ~c => e & d & f)");
    pi = formula.apply(MinimumPrimeImplicantFunction.get());
    assertThat(pi).hasSize(3);
    isPrimeImplicant(formula, pi);
    formula = this.f.parse("(a | b | ~c <=> e & d & f) | (a | b | ~c => e & d & f) | (a & b)");
    pi = formula.apply(MinimumPrimeImplicantFunction.get());
    assertThat(pi).hasSize(2);
    isPrimeImplicant(formula, pi);
    formula = this.f.parse("(a | b | ~c <=> e & d & f) | (a | b | ~c => e & d & f) | (a & b) | (f => g)");
    pi = formula.apply(MinimumPrimeImplicantFunction.get());
    assertThat(pi).hasSize(1);
    isPrimeImplicant(formula, pi);
}

Example 89 with Literal

use of org.logicng.formulas.Literal in project LogicNG by logic-ng.

the class QuineMcCluskeyTest method getTerm.

static Term getTerm(final String string, final FormulaFactory f) throws ParserException {
    final List<Literal> literals = new ArrayList<>();
    final PropositionalParser p = new PropositionalParser(f);
    for (final String var : string.split(" ")) {
        literals.add((Literal) p.parse(var));
    }
    return convertToTerm(literals, f);
}

Example 90 with Literal

use of org.logicng.formulas.Literal in project LogicNG by logic-ng.

the class SATTest method testLocalMinimum.

/**
 * Tests if the given satisfying assignment is a local minimal model regarding the given relevant literals, i.e.
 * there is no variable in the assignment, contained in the relevant literals, that can be flipped without
 * resulting in an unsatisfying assignment.
 * @param solver           the solver with the loaded formulas
 * @param assignment       the satisfying assignment
 * @param relevantLiterals the relevant literals.
 */
private void testLocalMinimum(final SATSolver solver, final Assignment assignment, final Collection<? extends Literal> relevantLiterals) {
    final SortedSet<Literal> literals = assignment.literals();
    for (final Literal lit : relevantLiterals) {
        if (!literals.contains(lit)) {
            final SortedSet<Literal> literalsWithFlip = new TreeSet<>(literals);
            literalsWithFlip.remove(lit.negate());
            literalsWithFlip.add(lit);
            assertThat(solver.sat(literalsWithFlip)).isEqualTo(Tristate.FALSE);
        }
    }
}