Examples with Constraint com.sri.ai.grinder.api.Constraint used on opensource projects

Example 6 with Constraint

use of com.sri.ai.grinder.api.Constraint in project aic-expresso by aic-sri-international.

the class SGDPLLTTester method testSingleVariableConstraints.

/**
 * Given a theory and a number <code>n</code> of single-variable constraint tests,
 * generates <code>n</code> formulas in the theory
 * and see if those detected as unsatisfiable by the corresponding solver
 * are indeed unsatisfiable (checked by brute force).
 * Throws an {@link Error} with the failure description if a test fails.
 * @param theoryTestingSupport
 * @param numberOfTests
 * @param maxNumberOfLiterals
 * @param outputCount
 */
public static void testSingleVariableConstraints(boolean testAgainstBruteForce, TheoryTestingSupport theoryTestingSupport, long numberOfTests, int maxNumberOfLiterals, boolean outputCount) {
    Context context = theoryTestingSupport.makeContextWithTestingInformation();
    NullaryFunction<Constraint> makeInitialConstraint = () -> theoryTestingSupport.getTheory().makeSingleVariableConstraint(parse(theoryTestingSupport.pickTestingVariableAtRandom()), context);
    Function<Constraint, Expression> makeRandomLiteral = c -> theoryTestingSupport.makeRandomLiteralOn(((SingleVariableConstraint) c).getVariable().toString(), context);
    boolean isComplete = theoryTestingSupport.getTheory().singleVariableConstraintIsCompleteWithRespectToItsVariable();
    TestRunner tester = isComplete ? SGDPLLTTester::testCompleteSatisfiability : SGDPLLTTester::testIncompleteSatisfiability;
    String problemName = (isComplete ? "complete" : "incomplete") + " satisfiability for single-variable constraints";
    runTesterGivenOnSuccessiveConjunctionsOfLiterals(problemName, tester, numberOfTests, maxNumberOfLiterals, testAgainstBruteForce, theoryTestingSupport, makeInitialConstraint, makeRandomLiteral, outputCount, context);
}

Example 7 with Constraint

use of com.sri.ai.grinder.api.Constraint in project aic-expresso by aic-sri-international.

the class SGDPLLTTester method runGroupProblemSolvingTestGivenConstraintAndProblem.

/**
 * @param problem
 * @param indices
 * @param constraint
 * @param body
 * @param testAgainstBruteForce
 * @param theoryTestingSupport
 * @param context
 * @throws Error
 */
public static void runGroupProblemSolvingTestGivenConstraintAndProblem(Expression problem, Collection<Expression> indices, Constraint constraint, Expression body, boolean testAgainstBruteForce, TheoryTestingSupport theoryTestingSupport, Context context) throws Error {
    Theory theory = theoryTestingSupport.getTheory();
    Collection<? extends Expression> freeVariables = getFreeVariableMinusIndices(indices, constraint, body, context);
    String problemDescription = problem.toString();
    output(problemDescription);
    Simplifier symbolicInterpreter = (e, c) -> theory.evaluate(e, c);
    long start = System.currentTimeMillis();
    Expression symbolicSolution = symbolicInterpreter.apply(problem, context);
    long time = System.currentTimeMillis() - start;
    output("Symbolic solution: " + symbolicSolution);
    output("Computed in " + time + " ms");
    if (Util.thereExists(new SubExpressionsDepthFirstIterator(symbolicSolution), e -> e instanceof QuantifiedExpression || Sets.isIntensionalSet(e))) {
        throw new Error("Symbolic solution is not quantifier-free: " + symbolicSolution);
    }
    if (testAgainstBruteForce) {
        BinaryFunction<BruteForceCommonInterpreter, Context, Expression> bruteForceSolutionGivenInterpreterAndContextWithAssignmentToOtherVariables = (i, c) -> i.apply(problem, c);
        testSymbolicVsBruteForceComputationForEachAssignment(theory, problemDescription, freeVariables, symbolicSolution, bruteForceSolutionGivenInterpreterAndContextWithAssignmentToOtherVariables, context);
    // A more elegant approach would be to create a "for all free variables : symbolic = problem" expression
    // and solve it by brute force instead of using testSymbolicVsBruteForceComputation
    // which replicates the brute force interpreter to some extent.
    // The reason we do not do this is simply due to the fact that the brute force interpreter would return "false"
    // in case of failure, without indicating which assignment failed, which is very useful for debugging.
    // If interpreters, and in fact the whole framework, provided proofs of its calculations,
    // then we could simply use the more elegant approach.
    } else {
        output("Skipping test againt brute-force.");
    }
}

Example 8 with Constraint

use of com.sri.ai.grinder.api.Constraint in project aic-expresso by aic-sri-international.

the class SGDPLLTTester method runTesterGivenOnSuccessiveConjunctionsOfLiterals.

/**
 * Generates a number of tests based on a conjunction each, which is formed by incrementally adding literals to it.
 * The conjunction is provided to a {@link TestRunner} which runs some test based on it.
 * Throws an {@link Error} with the failure description if a test fails.
 * @param tester the {@link TestRunner}
 * @param numberOfTests the number of tests to run
 * @param maxNumberOfLiterals the maximum number of literals to add to each test conjunction
 * @param theoryTestingSupport
 * @param makeInitialConstraint a thunk generating new constraints equivalent to TRUE
 * @param makeRandomLiteralGivenConstraint a function generating appropriate new literals (given generated constraint if needed)
 * @param outputCount whether to output the test count
 * @param context a context
 * @throws Error
 */
public static void runTesterGivenOnSuccessiveConjunctionsOfLiterals(String problemName, TestRunner tester, long numberOfTests, int maxNumberOfLiterals, boolean testAgainstBruteForce, TheoryTestingSupport theoryTestingSupport, NullaryFunction<Constraint> makeInitialConstraint, Function<Constraint, Expression> makeRandomLiteralGivenConstraint, boolean outputCount, Context context) throws Error {
    for (int i = 1; i != numberOfTests + 1; i++) {
        Constraint constraint = makeInitialConstraint.apply();
        Collection<Expression> literals = new LinkedHashSet<>();
        output("\n\nStarting new conjunction");
        for (int j = 0; !constraint.isContradiction() && j != maxNumberOfLiterals; j++) {
            Expression literal = makeRandomLiteralGivenConstraint.apply(constraint);
            constraint = addLiteralToConstraintAndTest(tester, literal, constraint, literals, testAgainstBruteForce, theoryTestingSupport, context);
        }
        indicateCompletionOfTest(outputCount, problemName, i, testAgainstBruteForce, theoryTestingSupport);
    }
}

Example 9 with Constraint

use of com.sri.ai.grinder.api.Constraint in project aic-expresso by aic-sri-international.

the class SGDPLLTTester method runGroupProblemSolvingTesterForSuccessiveConstraints.

private static void runGroupProblemSolvingTesterForSuccessiveConstraints(String problemName, TestRunner tester, boolean testAgainstBruteForce, AssociativeCommutativeGroup group, TheoryTestingSupport theoryTestingSupport, long numberOfTests, int maxNumberOfLiterals, boolean outputCount) throws Error {
    Context context = theoryTestingSupport.makeContextWithTestingInformation();
    NullaryFunction<Constraint> makeInitialConstraint = () -> theoryTestingSupport.getTheory().makeSingleVariableConstraint(parse(theoryTestingSupport.pickTestingVariableAtRandom()), context);
    Function<Constraint, Expression> makeRandomLiteral = c -> theoryTestingSupport.makeRandomLiteralOn(((SingleVariableConstraint) c).getVariable().toString(), context);
    runTesterGivenOnSuccessiveConjunctionsOfLiterals(problemName, tester, numberOfTests, maxNumberOfLiterals, testAgainstBruteForce, theoryTestingSupport, makeInitialConstraint, makeRandomLiteral, outputCount, context);
}

Example 10 with Constraint

use of com.sri.ai.grinder.api.Constraint in project aic-expresso by aic-sri-international.

the class SGDPLLTTester method testIncompleteMultiVariableConstraints.

/**
 * Given a theory and a number <code>n</code> of multi-variable constraint tests,
 * generates <code>n</code> formulas in the theory
 * and see if those detected as unsatisfiable by the corresponding incomplete solver
 * are indeed unsatisfiable (checked by brute force).
 * Note that we do not test if all unsatisfiable formulas are detected as such, because the solver is assumed to be incomplete.
 * Throws an {@link Error} with the failure description if a test fails.
 * @param theoryTestingSupport
 * @param numberOfTests
 * @param maxNumberOfLiterals
 * @param outputCount
 */
public static void testIncompleteMultiVariableConstraints(boolean testAgainstBruteForce, TheoryTestingSupport theoryTestingSupport, long numberOfTests, int maxNumberOfLiterals, boolean outputCount) {
    NullaryFunction<Constraint> makeInitialConstraint = () -> new IncompleteMultiVariableConstraint(theoryTestingSupport.getTheory());
    Context context = theoryTestingSupport.makeContextWithTestingInformation();
    Function<Constraint, Expression> makeRandomLiteral = c -> theoryTestingSupport.makeRandomLiteral(context);
    // {@link IncompleteMultiVariableConstraint} is incomplete
    TestRunner tester = SGDPLLTTester::testIncompleteSatisfiability;
    runTesterGivenOnSuccessiveConjunctionsOfLiterals("incomplete satisfiability", tester, numberOfTests, maxNumberOfLiterals, testAgainstBruteForce, theoryTestingSupport, makeInitialConstraint, makeRandomLiteral, outputCount, context);
}