Examples with LNGVector org.logicng.collections.LNGVector used on opensource projects

Example 6 with LNGVector

use of org.logicng.collections.LNGVector in project LogicNG by logic-ng.

the class PBConstraint method normalize.

/**
 * Normalizes this constraint s.t. it can be converted to CNF.
 * @return the normalized constraint
 */
public Formula normalize() {
    final LNGVector<Literal> normPs = new LNGVector<>(this.literals.length);
    final LNGIntVector normCs = new LNGIntVector(this.literals.length);
    int normRhs;
    switch(this.comparator) {
        case EQ:
            for (int i = 0; i < this.literals.length; i++) {
                normPs.push(this.literals[i]);
                normCs.push(this.coefficients[i]);
            }
            normRhs = this.rhs;
            final Formula f1 = this.normalize(normPs, normCs, normRhs);
            normPs.clear();
            normCs.clear();
            for (int i = 0; i < this.literals.length; i++) {
                normPs.push(this.literals[i]);
                normCs.push(-this.coefficients[i]);
            }
            normRhs = -this.rhs;
            final Formula f2 = this.normalize(normPs, normCs, normRhs);
            return this.f.and(f1, f2);
        case LT:
        case LE:
            for (int i = 0; i < this.literals.length; i++) {
                normPs.push(this.literals[i]);
                normCs.push(this.coefficients[i]);
            }
            normRhs = this.comparator == CType.LE ? this.rhs : this.rhs - 1;
            return this.normalize(normPs, normCs, normRhs);
        case GT:
        case GE:
            for (int i = 0; i < this.literals.length; i++) {
                normPs.push(this.literals[i]);
                normCs.push(-this.coefficients[i]);
            }
            normRhs = this.comparator == CType.GE ? -this.rhs : -this.rhs - 1;
            return this.normalize(normPs, normCs, normRhs);
        default:
            throw new IllegalStateException("Unknown pseudo-Boolean comparator: " + this.comparator);
    }
}

Example 7 with LNGVector

use of org.logicng.collections.LNGVector in project LogicNG by logic-ng.

the class CCAMONested method encodeIntern.

/**
 * Internal recursive encoding.
 * @param vars the variables of the constraint
 */
private void encodeIntern(final LNGVector<Literal> vars) {
    if (vars.size() <= this.groupSize) {
        for (int i = 0; i + 1 < vars.size(); i++) {
            for (int j = i + 1; j < vars.size(); j++) {
                this.result.addClause(vars.get(i).negate(), vars.get(j).negate());
            }
        }
    } else {
        final LNGVector<Literal> l1 = new LNGVector<>(vars.size() / 2);
        final LNGVector<Literal> l2 = new LNGVector<>(vars.size() / 2);
        int i = 0;
        for (; i < vars.size() / 2; i++) {
            l1.push(vars.get(i));
        }
        for (; i < vars.size(); i++) {
            l2.push(vars.get(i));
        }
        final Variable newVariable = this.result.newVariable();
        l1.push(newVariable);
        l2.push(newVariable.negate());
        this.encodeIntern(l1);
        this.encodeIntern(l2);
    }
}

Example 8 with LNGVector

use of org.logicng.collections.LNGVector in project LogicNG by logic-ng.

the class PBBinaryMerge method binary_merge.

private void binary_merge(final LNGVector<Literal> literals, final LNGIntVector coefficients, final int leq, final int maxWeight, final int n, final List<Formula> formula, final Literal gac_lit) {
    final int less_then = leq + 1;
    final int p = (int) Math.floor(Math.log(maxWeight) / Math.log(2));
    final int m = (int) Math.ceil(less_then / Math.pow(2, p));
    final int new_less_then = (int) (m * Math.pow(2, p));
    final int T = (int) ((m * Math.pow(2, p)) - less_then);
    final Literal true_lit = this.f.newPBVariable();
    formula.add(true_lit);
    final LNGVector<LNGVector<Literal>> buckets = new LNGVector<>();
    int bit = 1;
    for (int i = 0; i <= p; i++) {
        buckets.push(new LNGVector<>());
        if ((T & bit) != 0) {
            buckets.get(i).push(true_lit);
        }
        for (int j = 0; j < n; j++) {
            if ((coefficients.get(j) & bit) != 0) {
                if (gac_lit != null && coefficients.get(j) >= less_then) {
                    formula.add(this.f.clause(gac_lit, literals.get(j).negate()));
                } else {
                    buckets.get(i).push(literals.get(j));
                }
            }
        }
        bit = bit << 1;
    }
    final LNGVector<LNGVector<Literal>> bucket_card = new LNGVector<>(p + 1);
    final LNGVector<LNGVector<Literal>> bucket_merge = new LNGVector<>(p + 1);
    for (int i = 0; i < p + 1; i++) {
        bucket_card.push(new LNGVector<>());
        bucket_merge.push(new LNGVector<>());
    }
    assert bucket_card.size() == buckets.size();
    final LNGVector<Literal> carries = new LNGVector<>();
    final EncodingResult tempResul = EncodingResult.resultForFormula(this.f);
    for (int i = 0; i < buckets.size(); i++) {
        final int k = (int) Math.ceil(new_less_then / Math.pow(2, i));
        if (this.config.binaryMergeUseWatchDog) {
            totalizer(buckets.get(i), bucket_card.get(i), formula);
        } else {
            this.sorting.sort(k, buckets.get(i), tempResul, bucket_card.get(i), INPUT_TO_OUTPUT);
            formula.addAll(tempResul.result());
        }
        if (k <= buckets.get(i).size()) {
            assert k == bucket_card.get(i).size() || this.config.binaryMergeUseWatchDog;
            if (gac_lit != null) {
                formula.add(this.f.clause(gac_lit, bucket_card.get(i).get(k - 1).negate()));
            } else {
                formula.add(this.f.clause(bucket_card.get(i).get(k - 1).negate()));
            }
        }
        if (i > 0) {
            if (carries.size() > 0) {
                if (bucket_card.get(i).size() == 0) {
                    bucket_merge.set(i, carries);
                } else {
                    if (this.config.binaryMergeUseWatchDog) {
                        unary_adder(bucket_card.get(i), carries, bucket_merge.get(i), formula);
                    } else {
                        this.sorting.merge(k, bucket_card.get(i), carries, tempResul, bucket_merge.get(i), INPUT_TO_OUTPUT);
                        formula.addAll(tempResul.result());
                    }
                    if (k == bucket_merge.get(i).size() || (this.config.binaryMergeUseWatchDog && k <= bucket_merge.get(i).size())) {
                        if (gac_lit != null) {
                            formula.add(this.f.clause(gac_lit, bucket_merge.get(i).get(k - 1).negate()));
                        } else {
                            formula.add(this.f.clause(bucket_merge.get(i).get(k - 1).negate()));
                        }
                    }
                }
            } else {
                bucket_merge.get(i).replaceInplace(bucket_card.get(i));
            }
        }
        carries.clear();
        if (i == 0) {
            for (int j = 1; j < bucket_card.get(0).size(); j = j + 2) {
                carries.push(bucket_card.get(0).get(j));
            }
        } else {
            for (int j = 1; j < bucket_merge.get(i).size(); j = j + 2) {
                carries.push(bucket_merge.get(i).get(j));
            }
        }
    }
}

Example 9 with LNGVector

use of org.logicng.collections.LNGVector in project LogicNG by logic-ng.

the class PBBinaryMerge method encode.

@Override
public List<Formula> encode(final LNGVector<Literal> lts, final LNGIntVector cffs, final int rhs, final List<Formula> formula) {
    final LNGVector<Literal> lits = new LNGVector<>(lts.size());
    for (final Literal lit : lts) {
        lits.push(lit);
    }
    final LNGIntVector coeffs = new LNGIntVector(cffs);
    final int maxWeight = maxWeight(coeffs);
    if (!this.config.binaryMergeUseGAC) {
        binary_merge(lts, new LNGIntVector(cffs), rhs, maxWeight, lits.size(), formula, null);
    } else {
        Literal x;
        boolean encode_complete_constraint = false;
        for (int i = 0; i < lits.size(); i++) {
            if (this.config.binaryMergeNoSupportForSingleBit && Double.compare(Math.floor(Math.log(coeffs.get(i)) / Math.log(2)), Math.log(coeffs.get(i)) / Math.log(2)) == 0) {
                encode_complete_constraint = true;
                continue;
            }
            final Literal tmpLit = lits.get(i);
            final int tmpCoeff = coeffs.get(i);
            lits.set(i, lits.back());
            coeffs.set(i, coeffs.back());
            lits.pop();
            coeffs.pop();
            x = tmpLit;
            if (maxWeight == tmpCoeff) {
                int mw = 0;
                for (int j = 0; j < coeffs.size(); j++) {
                    mw = Math.max(mw, coeffs.get(j));
                }
                if (rhs - tmpCoeff <= 0) {
                    for (int j = 0; j < lits.size(); j++) {
                        formula.add(this.f.clause(x.negate(), lits.get(j).negate()));
                    }
                } else {
                    binary_merge(lits, coeffs, rhs - tmpCoeff, mw, lits.size(), formula, x.negate());
                }
            } else {
                if (rhs - tmpCoeff <= 0) {
                    for (int j = 0; j < lits.size(); j++) {
                        formula.add(this.f.clause(x.negate(), lits.get(j).negate()));
                    }
                }
                binary_merge(lits, coeffs, rhs - tmpCoeff, maxWeight, lits.size(), formula, x.negate());
            }
            if (i < lits.size()) {
                lits.push(lits.get(i));
                lits.set(i, tmpLit);
                coeffs.push(coeffs.get(i));
                coeffs.set(i, tmpCoeff);
            }
        }
        if (this.config.binaryMergeNoSupportForSingleBit && encode_complete_constraint) {
            binary_merge(lts, new LNGIntVector(cffs), rhs, maxWeight, lits.size(), formula, null);
        }
    }
    return formula;
}

Example 10 with LNGVector

use of org.logicng.collections.LNGVector in project LogicNG by logic-ng.

the class UnsatCoreFunction method apply.

@Override
public UNSATCore<Proposition> apply(final MiniSat solver, final Consumer<Tristate> resultSetter) {
    if (!solver.getConfig().proofGeneration()) {
        throw new IllegalStateException("Cannot generate an unsat core if proof generation is not turned on");
    }
    if (solver.getResult() == TRUE) {
        throw new IllegalStateException("An unsat core can only be generated if the formula is solved and is UNSAT");
    }
    if (solver.getResult() == Tristate.UNDEF) {
        throw new IllegalStateException("Cannot generate an unsat core before the formula was solved.");
    }
    if (solver.underlyingSolver() instanceof MiniCard) {
        throw new IllegalStateException("Cannot compute an unsat core with MiniCard.");
    }
    if (solver.underlyingSolver() instanceof GlucoseSyrup && solver.getConfig().incremental()) {
        throw new IllegalStateException("Cannot compute an unsat core with Glucose in incremental mode.");
    }
    if (solver.isLastComputationWithAssumptions()) {
        throw new IllegalStateException("Cannot compute an unsat core for a computation with assumptions.");
    }
    final DRUPTrim trimmer = new DRUPTrim();
    final Map<Formula, Proposition> clause2proposition = new HashMap<>();
    final LNGVector<LNGIntVector> clauses = new LNGVector<>(solver.underlyingSolver().pgOriginalClauses().size());
    for (final MiniSatStyleSolver.ProofInformation pi : solver.underlyingSolver().pgOriginalClauses()) {
        clauses.push(pi.clause());
        final Formula clause = getFormulaForVector(solver, pi.clause());
        Proposition proposition = pi.proposition();
        if (proposition == null) {
            proposition = new StandardProposition(clause);
        }
        clause2proposition.put(clause, proposition);
    }
    if (containsEmptyClause(clauses)) {
        final Proposition emptyClause = clause2proposition.get(solver.factory().falsum());
        return new UNSATCore<>(Collections.singletonList(emptyClause), true);
    }
    final DRUPTrim.DRUPResult result = trimmer.compute(clauses, solver.underlyingSolver().pgProof());
    if (result.trivialUnsat()) {
        return handleTrivialCase(solver);
    }
    final LinkedHashSet<Proposition> propositions = new LinkedHashSet<>();
    for (final LNGIntVector vector : result.unsatCore()) {
        propositions.add(clause2proposition.get(getFormulaForVector(solver, vector)));
    }
    return new UNSATCore<>(new ArrayList<>(propositions), false);
}