Examples with CompiledRule at.ac.tuwien.kr.alpha.core.rules.CompiledRule used on opensource projects

Example 1 with CompiledRule

use of at.ac.tuwien.kr.alpha.core.rules.CompiledRule in project Alpha by alpha-asp.

the class StratifiedEvaluation method apply.

@Override
public // memories created here rather than re-initialize everything.
InternalProgram apply(AnalyzedProgram inputProgram) {
    // Calculate a stratification and initialize the working memory.
    ComponentGraph componentGraph = inputProgram.getComponentGraph();
    List<ComponentGraph.SCComponent> strata = StratificationAlgorithm.calculateStratification(componentGraph);
    predicateDefiningRules = inputProgram.getPredicateDefiningRules();
    // Set up list of atoms which are known to be true - these will be expand by the evaluation.
    Map<Predicate, Set<Instance>> knownFacts = new LinkedHashMap<>(inputProgram.getFactsByPredicate());
    for (Map.Entry<Predicate, Set<Instance>> entry : knownFacts.entrySet()) {
        workingMemory.initialize(entry.getKey());
        workingMemory.addInstances(entry.getKey(), true, entry.getValue());
    }
    // Create working memories for all predicates occurring in each rule.
    for (CompiledRule nonGroundRule : inputProgram.getRulesById().values()) {
        for (Predicate predicate : nonGroundRule.getOccurringPredicates()) {
            workingMemory.initialize(predicate);
        }
    }
    workingMemory.reset();
    // Set up literal instantiator.
    literalInstantiator = new LiteralInstantiator(new WorkingMemoryBasedInstantiationStrategy(workingMemory));
    // Evaluate the program part covered by the calculated stratification.
    for (ComponentGraph.SCComponent currComponent : strata) {
        evaluateComponent(currComponent);
    }
    // Build the program resulting from evaluating the stratified part.
    // Add original input facts to newly derived ones.
    additionalFacts.addAll(inputProgram.getFacts());
    List<CompiledRule> outputRules = new ArrayList<>();
    inputProgram.getRulesById().entrySet().stream().filter((entry) -> !solvedRuleIds.contains(entry.getKey())).forEach((entry) -> outputRules.add(entry.getValue()));
    // NOTE: if InternalProgram requires solved rules, they should be added here.
    return new InternalProgram(outputRules, additionalFacts);
}

Example 2 with CompiledRule

use of at.ac.tuwien.kr.alpha.core.rules.CompiledRule in project Alpha by alpha-asp.

the class StratifiedEvaluation method getRulesToEvaluate.

private ComponentEvaluationInfo getRulesToEvaluate(ComponentGraph.SCComponent comp) {
    Set<CompiledRule> nonRecursiveRules = new HashSet<>();
    Set<CompiledRule> recursiveRules = new HashSet<>();
    // Collect all predicates occurring in heads of rules of the given component.
    Set<Predicate> headPredicates = new HashSet<>();
    for (DependencyGraph.Node node : comp.getNodes()) {
        headPredicates.add(node.getPredicate());
    }
    // cycle.
    for (Predicate headPredicate : headPredicates) {
        HashSet<CompiledRule> definingRules = predicateDefiningRules.get(headPredicate);
        if (definingRules == null) {
            // Predicate only occurs in facts, skip.
            continue;
        }
        // Note: here we assume that all rules defining a predicate belong to the same SC component.
        for (CompiledRule rule : definingRules) {
            boolean isRuleRecursive = false;
            for (Literal lit : rule.getPositiveBody()) {
                if (headPredicates.contains(lit.getPredicate())) {
                    // The rule body contains a predicate that is defined in the same
                    // component, the rule is therefore part of a cyclic dependency within
                    // this component.
                    isRuleRecursive = true;
                }
            }
            if (isRuleRecursive) {
                recursiveRules.add(rule);
            } else {
                nonRecursiveRules.add(rule);
            }
        }
    }
    return new ComponentEvaluationInfo(nonRecursiveRules, recursiveRules);
}

Example 3 with CompiledRule

use of at.ac.tuwien.kr.alpha.core.rules.CompiledRule 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 4 with CompiledRule

use of at.ac.tuwien.kr.alpha.core.rules.CompiledRule in project Alpha by alpha-asp.

the class RuleGroundingOrderTest method computeGroundingOrdersForRule.

private RuleGroundingInfo computeGroundingOrdersForRule(CompiledProgram program, int ruleIndex) {
    CompiledRule rule = program.getRules().get(ruleIndex);
    RuleGroundingInfo rgo = new RuleGroundingInfoImpl(rule);
    rgo.computeGroundingOrders();
    return rgo;
}

Example 5 with CompiledRule

use of at.ac.tuwien.kr.alpha.core.rules.CompiledRule in project Alpha by alpha-asp.

the class RuleGroundingOrderTest method groundingOrder.

@Test
public void groundingOrder() {
    String aspStr = "h(X,C) :- p(X,Y), q(A,B), r(Y,A), s(C)." + "j(A,B,X,Y) :- r1(A,B), r1(X,Y), r1(A,X), r1(B,Y), A = B." + "p(a) :- b = a.";
    CompiledProgram prog = PARSE_AND_PREPROCESS.apply(aspStr);
    CompiledRule rule0 = prog.getRules().get(0);
    RuleGroundingInfo rgo0 = new RuleGroundingInfoImpl(rule0);
    rgo0.computeGroundingOrders();
    assertEquals(4, rgo0.getStartingLiterals().size());
    CompiledRule rule1 = prog.getRules().get(1);
    RuleGroundingInfo rgo1 = new RuleGroundingInfoImpl(rule1);
    rgo1.computeGroundingOrders();
    assertEquals(4, rgo1.getStartingLiterals().size());
    CompiledRule rule2 = prog.getRules().get(2);
    RuleGroundingInfo rgo2 = new RuleGroundingInfoImpl(rule2);
    rgo2.computeGroundingOrders();
    assertTrue(rgo2.hasFixedInstantiation());
}