Examples with ThriceTruth at.ac.tuwien.kr.alpha.core.solver.ThriceTruth used on opensource projects

Example 1 with ThriceTruth

use of at.ac.tuwien.kr.alpha.core.solver.ThriceTruth in project Alpha by alpha-asp.

the class NaiveGrounderTest method testPermissiveGrounderHeuristicTolerance.

/**
 * Tests if {@link NaiveGrounder#getGroundInstantiations(InternalRule, RuleGroundingOrder, Substitution, Assignment)}
 * produces ground instantiations for the rule with ID {@code ruleID} in {@code program} when {@code startingLiteral}
 * unified with the numeric instance {@code startingInstance} is used as starting literal and the following
 * additional conditions are established:
 * <ul>
 * <li>The atoms {@code b([startingInstance], 1), ..., b([startingInstance], n)} are added to the grounder's
 * working memory without changing the assignment, where {@code arityOfB-1} occurences of {@code startingInstance}
 * are used instead of {@code [startingInstance]} and {@code n} is the length of the {@code truthsOfB} array.
 * For example, if the length of {@code truthsOfB} is 2 and {@code arityOfB} is also 2, these atoms are
 * {@code b(1,1), b(1,2)}.
 * </li>
 * <li>The same atoms are assigned the truth values in the {@code truthsOfB} array.</li>
 * </ul>
 * It is asserted that ground instantiations are produced if and only if {@code expectNoGoods} is true.
 * If ground instantiations are produced, it is also asserted that the numbers of unassigned positive body atoms
 * determined by {@code getGroundInstantiations} match those given in {@code expectedNumbersOfUnassignedPositiveBodyAtoms}.
 */
private void testPermissiveGrounderHeuristicTolerance(ASPCore2Program program, int ruleID, Literal startingLiteral, int startingInstance, int tolerance, ThriceTruth[] truthsOfB, int arityOfB, boolean expectNoGoods, List<Integer> expectedNumbersOfUnassignedPositiveBodyAtoms) {
    CompiledProgram internalPrg = InternalProgram.fromNormalProgram(NORMALIZE_TRANSFORM.apply(program));
    AtomStore atomStore = new AtomStoreImpl();
    TrailAssignment currentAssignment = new TrailAssignment(atomStore);
    GrounderHeuristicsConfiguration heuristicConfiguration = GrounderHeuristicsConfiguration.getInstance(tolerance, tolerance);
    NaiveGrounder grounder = (NaiveGrounder) GrounderFactory.getInstance("naive", internalPrg, atomStore, p -> true, heuristicConfiguration, true);
    int[] bAtomIDs = new int[truthsOfB.length];
    for (int i = 0; i < truthsOfB.length; i++) {
        int[] bTerms = new int[arityOfB];
        for (int n = 0; n < arityOfB; n++) {
            bTerms[n] = (n == arityOfB - 1) ? i + 1 : startingInstance;
        }
        bAtomIDs[i] = atomStore.putIfAbsent(atom("b", bTerms));
    }
    addAtomsToWorkingMemoryWithoutChangingTheAssignment(atomStore, grounder, bAtomIDs);
    assign(currentAssignment, bAtomIDs, truthsOfB);
    grounder.bootstrap();
    final CompiledRule nonGroundRule = grounder.getNonGroundRule(ruleID);
    final Substitution substStartingLiteral = BasicSubstitution.specializeSubstitution(startingLiteral, new Instance(Terms.newConstant(startingInstance)), BasicSubstitution.EMPTY_SUBSTITUTION);
    final BindingResult bindingResult = grounder.getGroundInstantiations(nonGroundRule, nonGroundRule.getGroundingInfo().orderStartingFrom(startingLiteral), substStartingLiteral, currentAssignment);
    assertEquals(expectNoGoods, bindingResult.size() > 0);
    if (bindingResult.size() > 0) {
        assertEquals(expectedNumbersOfUnassignedPositiveBodyAtoms, bindingResult.getNumbersOfUnassignedPositiveBodyAtoms());
    } else {
        assertTrue(bindingResult.getNumbersOfUnassignedPositiveBodyAtoms().isEmpty());
    }
}

Example 2 with ThriceTruth

use of at.ac.tuwien.kr.alpha.core.solver.ThriceTruth in project Alpha by alpha-asp.

the class AnalyzeUnjustified method analyze.

public Set<Literal> analyze(int atomToJustify, Assignment currentAssignment) {
    padDepth = 0;
    Atom atom = atomStore.get(atomToJustify);
    if (!(atom instanceof BasicAtom)) {
        throw oops("Starting atom must be a BasicAtom, but received: " + atom + " of type: " + atom.getClass());
    }
    // @formatter:off
    // Calling code must make sure it is a BasicAtom and take precautions.
    // Potential solutions:
    // If atom instanceof RuleAtom and atom is MBT, then the corresponding rule body has a BasicAtom that is MBT.
    // If atom instanceof ChoiceAtom and atom is MBT, then the corresponding rule body has a BasicAtom that is MBT.
    // If atom instanceof RuleAtom and atom is FALSE, then this comes from a violated constraint in the end and the corresponding rule body can be taken as the single rule deriving the RuleAtom.
    // @formatter:on
    assignedAtoms = new LinkedHashMap<>();
    for (int i = 1; i <= atomStore.getMaxAtomId(); i++) {
        ThriceTruth truth = currentAssignment.getTruth(i);
        if (truth == null) {
            continue;
        }
        Atom assignedAtom = atomStore.get(i);
        assignedAtoms.putIfAbsent(assignedAtom.getPredicate(), new ArrayList<>());
        assignedAtoms.get(assignedAtom.getPredicate()).add(assignedAtom);
    }
    return analyze((BasicAtom) atom, currentAssignment);
}

Example 3 with ThriceTruth

use of at.ac.tuwien.kr.alpha.core.solver.ThriceTruth in project Alpha by alpha-asp.

the class Assignment method isViolated.

default boolean isViolated(int literal) {
    final int atom = atomOf(literal);
    final ThriceTruth truth = getTruth(atom);
    // For unassigned atoms, any literal is not violated.
    return truth != null && isNegated(literal) != truth.toBoolean();
}

Example 4 with ThriceTruth

use of at.ac.tuwien.kr.alpha.core.solver.ThriceTruth in project Alpha by alpha-asp.

the class NaiveGrounderTest method testIfGrounderGroundsRule.

/**
 * Tests if {@link NaiveGrounder#getGroundInstantiations(InternalRule, RuleGroundingOrder, Substitution, Assignment)}
 * produces ground instantiations for the rule with ID {@code ruleID} in {@code program} when {@code startingLiteral}
 * unified with the numeric instance {@code startingInstance} is used as starting literal and {@code b(1)} is assigned
 * {@code bTruth}.
 * It is asserted that ground instantiations are produced if and only if {@code expectNoGoods} is true.
 */
private void testIfGrounderGroundsRule(ASPCore2Program program, int ruleID, Literal startingLiteral, int startingInstance, ThriceTruth bTruth, boolean expectNoGoods) {
    CompiledProgram internalPrg = InternalProgram.fromNormalProgram(NORMALIZE_TRANSFORM.apply(program));
    AtomStore atomStore = new AtomStoreImpl();
    TrailAssignment currentAssignment = new TrailAssignment(atomStore);
    NaiveGrounder grounder = (NaiveGrounder) GrounderFactory.getInstance("naive", internalPrg, atomStore, p -> true, GrounderHeuristicsConfiguration.permissive(), true);
    int b = atomStore.putIfAbsent(atom("b", 1));
    currentAssignment.growForMaxAtomId();
    currentAssignment.assign(b, bTruth);
    grounder.bootstrap();
    final CompiledRule nonGroundRule = grounder.getNonGroundRule(ruleID);
    final Substitution substStartingLiteral = BasicSubstitution.specializeSubstitution(startingLiteral, new Instance(Terms.newConstant(startingInstance)), BasicSubstitution.EMPTY_SUBSTITUTION);
    final BindingResult bindingResult = grounder.getGroundInstantiations(nonGroundRule, nonGroundRule.getGroundingInfo().orderStartingFrom(startingLiteral), substStartingLiteral, currentAssignment);
    assertEquals(expectNoGoods, bindingResult.size() > 0);
}