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

Example 31 with PBConstraint

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

the class FormulaRandomizerTest method testExo.

@Test
public void testExo() {
    final FormulaRandomizer random = new FormulaRandomizer(this.f, FormulaRandomizerConfig.builder().seed(4242).maximumCoefficientPbc(10).build());
    for (int i = 0; i < 100; i++) {
        final Formula formula = random.exo();
        assertThat(formula).isInstanceOf(PBConstraint.class);
        final PBConstraint amo = (PBConstraint) formula;
        assertThat(amo.isCC()).isTrue();
        assertThat(amo.rhs()).isEqualTo(1);
        assertThat(amo.comparator()).isEqualTo(CType.EQ);
    }
}

Example 32 with PBConstraint

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

the class FormulaDotFileWriter method generateDotString.

/**
 * Generates the dot string for a formula
 * @param formula the formula
 * @param sb      the current string builder
 * @param ids     the current ID mapping
 */
private static void generateDotString(final Formula formula, final StringBuilder sb, final Map<Formula, Integer> ids) {
    switch(formula.type()) {
        case FALSE:
            sb.append(String.format("  false;%n"));
            break;
        case TRUE:
            sb.append(String.format("  true;%n"));
            break;
        case LITERAL:
            break;
        case PBC:
            final int id = ids.size();
            ids.put(formula, id);
            sb.append("  id").append(id).append(" [label=\"").append(formula).append(String.format("\"];%n"));
            for (final Formula operand : ((PBConstraint) formula).operands()) {
                sb.append("  id").append(id).append(" -> id").append(ids.get(operand)).append(String.format(";%n"));
            }
            break;
        case NOT:
            generateNotDotString((Not) formula, sb, ids);
            break;
        case IMPL:
            generateBinaryDotString((BinaryOperator) formula, sb, ids, "⇒", true);
            break;
        case EQUIV:
            generateBinaryDotString((BinaryOperator) formula, sb, ids, "⇔", true);
            break;
        case AND:
            generateNaryDotString((NAryOperator) formula, sb, ids, "∧");
            break;
        case OR:
            generateNaryDotString((NAryOperator) formula, sb, ids, "∨");
            break;
        default:
            throw new IllegalArgumentException("Cannot write the formula type " + formula.type());
    }
}

Example 33 with PBConstraint

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

the class NumberOfNodesFunction method apply.

@Override
public Long apply(final Formula formula, final boolean cache) {
    final Object cached = formula.functionCacheEntry(NUMBER_OF_NODES);
    if (cached != null) {
        return (Long) cached;
    }
    long result;
    switch(formula.type()) {
        case FALSE:
        case TRUE:
        case LITERAL:
            result = 1L;
            break;
        case NOT:
            result = apply(((Not) formula).operand(), cache) + 1L;
            break;
        case IMPL:
        case EQUIV:
            final BinaryOperator binary = (BinaryOperator) formula;
            result = apply(binary.left(), cache) + apply(binary.right(), cache) + 1L;
            break;
        case OR:
        case AND:
            final NAryOperator nary = (NAryOperator) formula;
            result = 1L;
            for (final Formula op : nary) {
                result += apply(op, cache);
            }
            break;
        case PBC:
            final PBConstraint pbc = (PBConstraint) formula;
            result = 1L + pbc.operands().length;
            break;
        default:
            throw new IllegalStateException("Unknown formula type " + formula.type());
    }
    if (cache) {
        formula.setFunctionCacheEntry(NUMBER_OF_NODES, result);
    }
    return result;
}

Example 34 with PBConstraint

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

the class LiteralsFunction method apply.

@Override
public SortedSet<Literal> apply(final Formula formula, final boolean cache) {
    final Object cached = formula.functionCacheEntry(LITERALS);
    if (cached != null) {
        return (SortedSet<Literal>) cached;
    }
    SortedSet<Literal> result = new TreeSet<>();
    switch(formula.type()) {
        case FALSE:
        case TRUE:
            result = new TreeSet<>();
            break;
        case LITERAL:
            final Literal lit = (Literal) formula;
            result.add(lit);
            break;
        case NOT:
            final Not not = (Not) formula;
            result = apply(not.operand(), cache);
            break;
        case IMPL:
        case EQUIV:
            final BinaryOperator binary = (BinaryOperator) formula;
            result.addAll(apply(binary.left(), cache));
            result.addAll(apply(binary.right(), cache));
            break;
        case OR:
        case AND:
            final NAryOperator nary = (NAryOperator) formula;
            for (final Formula op : nary) {
                result.addAll(apply(op, cache));
            }
            break;
        case PBC:
            final PBConstraint pbc = (PBConstraint) formula;
            result = FormulaHelper.literals(pbc.operands());
            break;
        default:
            throw new IllegalStateException("Unknown formula type " + formula.type());
    }
    result = Collections.unmodifiableSortedSet(result);
    if (cache) {
        formula.setFunctionCacheEntry(LITERALS, result);
    }
    return result;
}

Example 35 with PBConstraint

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

the class BFSOrdering method bfs.

private LinkedHashSet<Variable> bfs(final Formula formula) {
    final LinkedHashSet<Variable> variables = new LinkedHashSet<>();
    final Queue<Formula> queue = new LinkedList<>();
    queue.add(formula);
    while (!queue.isEmpty()) {
        final Formula current = queue.remove();
        switch(current.type()) {
            case LITERAL:
                final Literal lit = (Literal) current;
                if (lit.phase()) {
                    variables.add(lit.variable());
                } else {
                    queue.add(lit.variable());
                }
                break;
            case NOT:
                queue.add(((Not) current).operand());
                break;
            case IMPL:
            case EQUIV:
                final BinaryOperator op = (BinaryOperator) current;
                queue.add(op.left());
                queue.add(op.right());
                break;
            case AND:
            case OR:
                for (final Formula operand : current) {
                    queue.add(operand);
                }
                break;
            case PBC:
                final PBConstraint pbc = (PBConstraint) current;
                for (final Literal literal : pbc.operands()) {
                    variables.add(literal.variable());
                }
                break;
        }
    }
    return variables;
}