public Object visitPredicate(Predicate predicate, Object arg)
{
foreach (Term t in predicate.getTerms())
{
t.accept(this, arg);
}
return predicate;
}
//
// START-FOLVisitor
public Object visitPredicate(Predicate p, Object arg) {
foreach (Term t in p.getArgs()) {
// Finish processing if have found a match
if (null != matchingTerm) {
break;
}
t.accept(this, null);
}
return p;
}
public Object visitPredicate(Predicate predicate, Object arg)
{
List<Term> terms = predicate.getTerms();
List<Term> newTerms = new List<Term>();
for (int i = 0; i < terms.Count; i++)
{
Term t = terms[i];
Term subsTerm = (Term)t.accept(this, arg);
newTerms.Add(subsTerm);
}
return new Predicate(predicate.getPredicateName(), newTerms);
}
//
// PRIVATE METHODS
//
private void constructFOLEg() {
ithExampleConstant = new Constant(folDSDomain.getExampleConstant(egNo));
List<Term> terms = new List<Term>();
terms.Add(ithExampleConstant);
// Create the classification sentence
classification = new Predicate(folDSDomain.getGoalPredicateName(),
terms);
if (!example.getAttributeValueAsString(
folDSDomain.getDataSetTargetName()).Equals(
folDSDomain.getTrueGoalValue())) {
// if not true then needs to be a Not sentence
classification = new NotSentence(classification);
}
// Create the description sentence
List<Sentence> descParts = new List<Sentence>();
foreach (String dname in folDSDomain.getDescriptionDataSetNames()) {
String foldDName = folDSDomain.getFOLName(dname);
terms = new List<Term>();
terms.Add(ithExampleConstant);
// If multivalued becomes a two place predicate
// e.g: Patrons(X1, Some)
// otherwise: Hungry(X1) or ~ Hungry(X1)
// see pg 769 of AIMA
Sentence part = null;
if (folDSDomain.isMultivalued(dname)) {
terms.Add(new Constant(folDSDomain.getFOLName(example
.getAttributeValueAsString(dname))));
part = new Predicate(foldDName, terms);
} else {
part = new Predicate(foldDName, terms);
// Need to determine if false
if (!folDSDomain.getTrueGoalValue().Equals(
example.getAttributeValueAsString(dname))) {
part = new NotSentence(part);
}
}
descParts.Add(part);
}
if (descParts.Count == 1) {
description = descParts[0];
} else if (descParts.Count > 1) {
description = new ConnectedSentence(Connectors.AND, descParts
[0], descParts[1]);
for (int i = 2; i < descParts.Count; i++) {
description = new ConnectedSentence(Connectors.AND,
description, descParts[i]);
}
}
}
protected void testDefiniteClauseKBKingsQueryRichardEvilFalse(
InferenceProcedure infp)
{
FOLKnowledgeBase kkb = FOLKnowledgeBaseFactory
.createKingsKnowledgeBase(infp);
List<Term> terms = new List<Term>();
terms.Add(new Constant("Richard"));
Predicate query = new Predicate("Evil", terms);
InferenceResult answer = kkb.ask(query);
Assert.IsTrue(null != answer);
Assert.IsTrue(answer.isPossiblyFalse());
Assert.IsFalse(answer.isTrue());
Assert.IsFalse(answer.isUnknownDueToTimeout());
Assert.IsFalse(answer.isPartialResultDueToTimeout());
Assert.IsTrue(0 == answer.getProofs().Count);
}
public void testSimpleVariableUnification()
{
Variable var1 = new Variable("x");
List<Term> terms1 = new List<Term>();
terms1.Add(var1);
Predicate p1 = new Predicate("King", terms1); // King(x)
List<Term> terms2 = new List<Term>();
terms2.Add(new Constant("John"));
Predicate p2 = new Predicate("King", terms2); // King(John)
Dictionary<Variable, Term> result = unifier.unify(p1, p2, theta);
Assert.AreEqual(theta, result);
Assert.AreEqual(1, theta.Keys.Count);
Assert.IsTrue(theta.ContainsKey(new Variable("x"))); // x =
Assert.AreEqual(new Constant("John"), theta[var1]); // John
}
protected void testDefiniteClauseKBKingsQueryEvilXReturnsJohnSucceeds(
InferenceProcedure infp)
{
FOLKnowledgeBase kkb = FOLKnowledgeBaseFactory
.createKingsKnowledgeBase(infp);
List<Term> terms = new List<Term>();
terms.Add(new Variable("x"));
Predicate query = new Predicate("Evil", terms);
InferenceResult answer = kkb.ask(query);
Assert.IsTrue(null != answer);
Assert.IsFalse(answer.isPossiblyFalse());
Assert.IsTrue(answer.isTrue());
Assert.IsFalse(answer.isUnknownDueToTimeout());
Assert.IsFalse(answer.isPartialResultDueToTimeout());
Assert.IsTrue(1 == answer.getProofs().Count);
Assert.IsTrue(1 == answer.getProofs()[0].getAnswerBindings()
.Count);
Assert.AreEqual(new Constant("John"), answer.getProofs()[0]
.getAnswerBindings()[new Variable("x")]);
}
protected void testDefiniteClauseKBKingsQueryKingXReturnsJohnAndRichardSucceeds(
InferenceProcedure infp)
{
FOLKnowledgeBase kkb = FOLKnowledgeBaseFactory
.createKingsKnowledgeBase(infp);
List<Term> terms = new List<Term>();
terms.Add(new Variable("x"));
Predicate query = new Predicate("King", terms);
InferenceResult answer = kkb.ask(query);
Assert.IsTrue(null != answer);
Assert.IsFalse(answer.isPossiblyFalse());
Assert.IsTrue(answer.isTrue());
Assert.IsFalse(answer.isUnknownDueToTimeout());
Assert.IsFalse(answer.isPartialResultDueToTimeout());
Assert.IsTrue(2 == answer.getProofs().Count);
Assert.IsTrue(1 == answer.getProofs()[0].getAnswerBindings()
.Count);
Assert.IsTrue(1 == answer.getProofs()[1].getAnswerBindings()
.Count);
bool gotJohn, gotRichard;
gotJohn = gotRichard = false;
Constant cJohn = new Constant("John");
Constant cRichard = new Constant("Richard");
foreach (Proof p in answer.getProofs())
{
Dictionary<Variable, Term> ans = p.getAnswerBindings();
Assert.AreEqual(1, ans.Count);
if (cJohn.Equals(ans[new Variable("x")]))
{
gotJohn = true;
}
if (cRichard.Equals(ans[new Variable("x")]))
{
gotRichard = true;
}
}
Assert.IsTrue(gotJohn);
Assert.IsTrue(gotRichard);
}
protected void testEqualityAndSubstitutionNoAxiomsKBabcdPFFASucceeds(
InferenceProcedure infp, bool expectedToFail)
{
FOLKnowledgeBase akb = FOLKnowledgeBaseFactory
.createABCDEqualityAndSubstitutionKnowledgeBase(infp, false);
List<Term> terms = new List<Term>();
terms.Add(new Constant("A"));
Function fa = new Function("F", terms);
terms = new List<Term>();
terms.Add(fa);
Function ffa = new Function("F", terms);
terms = new List<Term>();
terms.Add(ffa);
Predicate query = new Predicate("P", terms);
InferenceResult answer = akb.ask(query);
Assert.IsTrue(null != answer);
if (expectedToFail)
{
Assert.IsTrue(answer.isPossiblyFalse());
Assert.IsFalse(answer.isTrue());
Assert.IsFalse(answer.isUnknownDueToTimeout());
Assert.IsFalse(answer.isPartialResultDueToTimeout());
Assert.IsTrue(0 == answer.getProofs().Count);
}
else
{
Assert.IsFalse(answer.isPossiblyFalse());
Assert.IsTrue(answer.isTrue());
Assert.IsFalse(answer.isUnknownDueToTimeout());
Assert.IsFalse(answer.isPartialResultDueToTimeout());
Assert.IsTrue(1 == answer.getProofs().Count);
Assert.IsTrue(0 == answer.getProofs()[0]
.getAnswerBindings().Count);
}
}
protected void testFullFOLKBLovesAnimalQueryKillsJackTunaFalse(
InferenceProcedure infp, bool expectedToTimeOut)
{
FOLKnowledgeBase akb = FOLKnowledgeBaseFactory
.createLovesAnimalKnowledgeBase(infp);
List<Term> terms = new List<Term>();
terms.Add(new Constant("Jack"));
terms.Add(new Constant("Tuna"));
Predicate query = new Predicate("Kills", terms);
InferenceResult answer = akb.ask(query);
Assert.IsTrue(null != answer);
if (expectedToTimeOut)
{
Assert.IsFalse(answer.isPossiblyFalse());
Assert.IsFalse(answer.isTrue());
Assert.IsTrue(answer.isUnknownDueToTimeout());
Assert.IsFalse(answer.isPartialResultDueToTimeout());
Assert.IsTrue(0 == answer.getProofs().Count);
}
else
{
Assert.IsTrue(answer.isPossiblyFalse());
Assert.IsFalse(answer.isTrue());
Assert.IsFalse(answer.isUnknownDueToTimeout());
Assert.IsFalse(answer.isPartialResultDueToTimeout());
Assert.IsTrue(0 == answer.getProofs().Count);
}
}
protected void testHornClauseKBRingOfThievesQuerySkisXReturnsNancyRedBertDrew(
InferenceProcedure infp)
{
FOLKnowledgeBase rotkb = FOLKnowledgeBaseFactory
.createRingOfThievesKnowledgeBase(infp);
List<Term> terms = new List<Term>();
terms.Add(new Variable("x"));
Predicate query = new Predicate("Skis", terms);
InferenceResult answer = rotkb.ask(query);
Assert.IsTrue(null != answer);
Assert.IsFalse(answer.isPossiblyFalse());
Assert.IsTrue(answer.isTrue());
Assert.IsFalse(answer.isUnknownDueToTimeout());
// DB can expand infinitely so is only partial.
Assert.IsTrue(answer.isPartialResultDueToTimeout());
Assert.AreEqual(4, answer.getProofs().Count);
Assert.AreEqual(1, answer.getProofs()[0].getAnswerBindings()
.Count);
Assert.AreEqual(1, answer.getProofs()[1].getAnswerBindings()
.Count);
Assert.AreEqual(1, answer.getProofs()[2].getAnswerBindings()
.Count);
Assert.AreEqual(1, answer.getProofs()[3].getAnswerBindings()
.Count);
List<Constant> expected = new List<Constant>();
expected.Add(new Constant("Nancy"));
expected.Add(new Constant("Red"));
expected.Add(new Constant("Bert"));
expected.Add(new Constant("Drew"));
foreach (Proof p in answer.getProofs())
{
expected.Remove((Constant)p.getAnswerBindings()[new Variable("x")]);
}
Assert.AreEqual(0, expected.Count);
}
public Object visitPredicate(Predicate p, Object arg)
{
List<Predicate> predicates = (List<Predicate>)arg;
predicates.Add(p);
return predicates;
}
public Object visitPredicate(Predicate p, Object arg)
{
return p;
}
public Object visitPredicate(Predicate p, Object arg)
{
ArgData ad = (ArgData)arg;
if (ad.negated)
{
ad.clauses[ad.clauses.Count - 1].addNegativeLiteral(p);
}
else
{
ad.clauses[ad.clauses.Count - 1].addPositiveLiteral(p);
}
return p;
}
//
// START-FOLVisitor
public Object visitPredicate(Predicate p, Object arg)
{
List<Term> newTerms = new List<Term>();
foreach (Term t in p.getTerms())
{
Term subsTerm = (Term)t.accept(this, arg);
newTerms.Add(subsTerm);
}
return new Predicate(p.getPredicateName(), newTerms);
}
