Examples with IntIterator kodkod.util.ints.IntIterator used on opensource projects

Example 6 with IntIterator

use of kodkod.util.ints.IntIterator in project org.alloytools.alloy by AlloyTools.

the class RCEStrategy method next.

/**
 * {@inheritDoc}
 *
 * @see kodkod.engine.satlab.ReductionStrategy#next(kodkod.engine.satlab.ResolutionTrace)
 */
@Override
public IntSet next(ResolutionTrace trace) {
    if (varsToTry.isEmpty())
        // tried everything
        return Ints.EMPTY_SET;
    final IntSet relevantVars = StrategyUtils.coreTailUnits(trace);
    for (IntIterator varItr = varsToTry.iterator(); varItr.hasNext(); ) {
        final int var = varItr.next();
        varItr.remove();
        if (relevantVars.remove(var)) {
            // relevant variables
            if (relevantVars.isEmpty())
                // there was only root formula left
                break;
            // get all axioms and resolvents corresponding to the clauses
            // that
            // form the translations of formulas identified by relevant vars
            final IntSet relevantClauses = clausesFor(trace, relevantVars);
            assert !relevantClauses.isEmpty() && !relevantClauses.contains(trace.size() - 1);
            return relevantClauses;
        }
    }
    varsToTry.clear();
    return Ints.EMPTY_SET;
}

Example 7 with IntIterator

use of kodkod.util.ints.IntIterator in project org.alloytools.alloy by AlloyTools.

the class StrategyUtils method clausesFor.

/**
 * Returns the indices of all axioms in the given trace that form the
 * translations of the formulas identified by the given variables. This method
 * assumes that the axioms in the given trace were generated by the Kodkod
 * {@linkplain Translator}.
 *
 * @return let C = { c: trace.prover.clauses | c.maxVariable() in relevantVars
 *         }, T = { c1, c2: C | c2.maxVariable() in abs(c1.literals) } | C.*T
 */
static IntSet clausesFor(ResolutionTrace trace, IntSet relevantVars) {
    // System.out.println("relevant: " + relevantVars);
    final IntSet axioms = trace.axioms();
    final IntSet reachableVars = new IntBitSet(relevantVars.max() + 1);
    reachableVars.addAll(relevantVars);
    final IntSet relevantAxioms = new IntBitSet(axioms.size());
    final Iterator<Clause> itr = trace.reverseIterator(axioms);
    for (int i = axioms.max(); i >= 0; i--) {
        Clause clause = itr.next();
        int maxVar = clause.maxVariable();
        if (reachableVars.contains(maxVar)) {
            for (IntIterator lits = clause.literals(); lits.hasNext(); ) {
                reachableVars.add(StrictMath.abs(lits.next()));
            }
            relevantAxioms.add(i);
        }
    }
    return relevantAxioms;
}

Example 8 with IntIterator

use of kodkod.util.ints.IntIterator in project org.alloytools.alloy by AlloyTools.

the class StrategyUtils method coreVars.

/**
 * Returns the variables that correspond to the roots of log.formula, in the
 * order in which they were specified in log.formula.
 *
 * @return variables that correspond to the roots of log.formula, in the order
 *         in which they were specified in log.formula.
 */
// static IntVector orderedRootVars(TranslationLog log) {
// final Set<Formula> roots = log.roots();
// final Map<Formula,int[]> maxRootVar = new
// LinkedHashMap<Formula,int[]>(roots.size());
// final RecordFilter filter = new RecordFilter() {
// public boolean accept(Node node, int literal, Map<Variable, TupleSet>
// env) {
// return roots.contains(node) && env.isEmpty();
// }
// };
// for(Iterator<TranslationRecord> itr = log.replay(filter); itr.hasNext();)
// {
// TranslationRecord record = itr.next();
// int[] var = maxRootVar.get(record.node());
// if (var==null) {
// var = new int[1];
// maxRootVar.put((Formula)record.node(), var);
// }
// var[0] = StrictMath.abs(record.literal());
// }
// final IntSet uniqueRoots = new IntTreeSet();
// final IntVector orderedRoots = new ArrayIntVector(roots.size());
// for(int[] var : maxRootVar.values()) {
// int topVar = var[0];
// if (topVar != Integer.MAX_VALUE) // formula simplified to TRUE
// if (uniqueRoots.add(var[0])) {
// orderedRoots.add(var[0]);
// };
// }
// return orderedRoots;
// }
/**
 * Returns relevant core variables; that is, all variables that occur both in
 * the positive and negative phase in trace.core.
 *
 * @return { v: [1..) | (some p, n: trace.core | v in trace.elts[p].literals and
 *         -v in trace.elts[n].literals) }
 */
public static IntSet coreVars(ResolutionTrace trace) {
    final IntSet posVars = new IntTreeSet(), negVars = new IntTreeSet();
    for (Iterator<Clause> iter = trace.iterator(trace.core()); iter.hasNext(); ) {
        Clause clause = iter.next();
        for (IntIterator lits = clause.literals(); lits.hasNext(); ) {
            int lit = lits.next();
            if (lit > 0)
                posVars.add(lit);
            else
                negVars.add(-lit);
        }
    }
    posVars.retainAll(negVars);
    assert !posVars.isEmpty();
    final IntSet ret = new IntBitSet(posVars.max() + 1);
    ret.addAll(posVars);
    return ret;
}

Example 9 with IntIterator

use of kodkod.util.ints.IntIterator in project org.alloytools.alloy by AlloyTools.

the class Clause method toString.

/**
 * Returns a string representation of this clause.
 *
 * @return a string representation of this clause.
 */
@Override
public String toString() {
    final StringBuilder ret = new StringBuilder();
    if (numberOfAntecedents() == 0) {
        ret.append("AXIOM");
    } else {
        ret.append("RESOLVENT");
    }
    ret.append(". Literals: {");
    for (IntIterator iter = literals(); iter.hasNext(); ) {
        ret.append(" ");
        ret.append(iter.next());
    }
    ret.append(" }");
    return ret.toString();
}

Example 10 with IntIterator

use of kodkod.util.ints.IntIterator in project org.alloytools.alloy by AlloyTools.

the class Clause method equals.

/**
 * // * Returns the antecedent at the given index. // * @requires 0 <= index <
 * this.numberOfAntecedents() // * @return this.antecedents[index] // * @throws
 * IndexOutOfBoundsException index < 0 || index >= this.numberOfAntecedents() //
 */
// public abstract Clause antecedent(int index);
/**
 * Returns true if o is a Clause whose literals and antecedents are
 * <tt>equal</tt> to those of this clause.
 *
 * @return o in Clause && o.literals.equals(this.literals) &&
 *         o.antecedents.equals(this.antecedents)
 */
@Override
public boolean equals(Object o) {
    if (o == this)
        return true;
    if (o instanceof Clause) {
        final Clause c = (Clause) o;
        if (size() == c.size()) {
            final IntIterator itr1 = literals(), itr2 = literals();
            while (itr1.hasNext()) {
                if (itr1.next() != itr2.next())
                    return false;
            }
        }
        final int ante = numberOfAntecedents();
        if (ante > 0 && ante == c.numberOfAntecedents()) {
            final Iterator<Clause> itr1 = antecedents(), itr2 = c.antecedents();
            while (itr1.hasNext()) {
                if (!itr1.next().equals(itr2.next()))
                    return false;
            }
        }
        return ante == 0;
    }
    return false;
}