Examples with SolverState org.logicng.solvers.SolverState used on opensource projects

Example 21 with SolverState

use of org.logicng.solvers.SolverState in project LogicNG by logic-ng.

the class SATTest method testAddWithoutUnknown.

@Test
public void testAddWithoutUnknown() throws ParserException {
    final PropositionalParser parser = new PropositionalParser(this.f);
    final Formula phi = parser.parse("x1 & (~x2 | x3) & (x4 | ~x5)");
    final SortedSet<Variable> phiVars = new TreeSet<>(Arrays.asList(this.f.variable("x1"), this.f.variable("x2"), this.f.variable("x3"), this.f.variable("x4"), this.f.variable("x5")));
    final Formula add1 = parser.parse("x1 | x6 | x7");
    final Formula add2 = parser.parse("~x1 | ~x6 | x8");
    final Formula add3 = parser.parse("x2 & ~x3 | x7");
    final Formula add4 = parser.parse("x8 | x9");
    final SATSolver minisat = MiniSat.miniSat(this.f);
    final SATSolver minicard = MiniSat.miniCard(this.f);
    final SATSolver[] solvers = new SATSolver[] { minisat, minicard };
    for (final SATSolver solver : solvers) {
        solver.add(phi);
        solver.addWithoutUnknown(add1);
        assertThat(solver.sat()).isEqualTo(Tristate.TRUE);
        assertThat(solver.model().formula(this.f).variables()).isEqualTo(phiVars);
        solver.addWithoutUnknown(add2);
        assertThat(solver.sat()).isEqualTo(Tristate.TRUE);
        assertThat(solver.model().formula(this.f).variables()).isEqualTo(phiVars);
        if (solver instanceof MiniSat) {
            final SolverState state = solver.saveState();
            solver.addWithoutUnknown(add3);
            assertThat(solver.sat()).isEqualTo(Tristate.FALSE);
            solver.loadState(state);
            solver.add(add1);
            assertThat(solver.sat()).isEqualTo(Tristate.TRUE);
            assertThat(solver.model().formula(this.f).variables().containsAll(Arrays.asList(this.f.variable("x6"), this.f.variable("x7")))).isTrue();
            solver.loadState(state);
            solver.sat();
            assertThat(solver.model().formula(this.f).variables()).isEqualTo(phiVars);
        } else {
            solver.add(add1);
            assertThat(solver.sat()).isEqualTo(Tristate.TRUE);
            assertThat(solver.model().formula(this.f).variables().containsAll(Arrays.asList(this.f.variable("x6"), this.f.variable("x7")))).isTrue();
            solver.add(this.f.variable("x7"));
            assertThat(solver.sat()).isEqualTo(Tristate.TRUE);
            assertThat(solver.model().formula(this.f).variables().containsAll(Arrays.asList(this.f.variable("x6"), this.f.variable("x7")))).isTrue();
            solver.addWithoutUnknown(add4);
            assertThat(solver.sat()).isEqualTo(Tristate.FALSE);
        }
    }
}

Example 22 with SolverState

use of org.logicng.solvers.SolverState in project LogicNG by logic-ng.

the class DeletionBasedMUS method computeMUS.

@Override
public <T extends Proposition> UNSATCore<T> computeMUS(final List<T> propositions, final FormulaFactory f, final MUSConfig config) {
    start(config.handler);
    final List<T> mus = new ArrayList<>(propositions.size());
    final List<SolverState> solverStates = new ArrayList<>(propositions.size());
    final MiniSat solver = MiniSat.miniSat(f);
    for (final Proposition proposition : propositions) {
        solverStates.add(solver.saveState());
        solver.add(proposition);
    }
    boolean sat = solver.sat() == Tristate.TRUE;
    if (aborted(config.handler)) {
        return null;
    }
    if (sat) {
        throw new IllegalArgumentException("Cannot compute a MUS for a satisfiable formula set.");
    }
    for (int i = solverStates.size() - 1; i >= 0; i--) {
        solver.loadState(solverStates.get(i));
        for (final Proposition prop : mus) {
            solver.add(prop);
        }
        sat = solver.sat(config.handler) == Tristate.TRUE;
        if (aborted(config.handler)) {
            return null;
        }
        if (sat) {
            mus.add(propositions.get(i));
        }
    }
    return new UNSATCore<>(mus, true);
}