public void testNestedExistsAndOrs()
{
FOLDomain domain = new FOLDomain();
domain.addPredicate("P");
domain.addPredicate("R");
domain.addPredicate("Q");
FOLParser parser = new FOLParser(domain);
Sentence origSentence = parser
.parse("EXISTS w (FORALL x ( (EXISTS z (Q(w, z))) => (EXISTS y (NOT(P(x, y)) AND R(y))) ) )");
CNFConverter cnfConv = new CNFConverter(parser);
CNF cnf = cnfConv.convertToCNF(origSentence);
Assert.AreEqual("[~P(x,SF0(x)), ~Q(SC0,z)],[~Q(SC0,z), R(SF0(x))]",
cnf.ToString());
// Ax.Ay.(p(x,y) => Ez.(q(x,y,z)))
origSentence = parser
.parse("FORALL x1 (FORALL y1 (P(x1, y1) => EXISTS z1 (Q(x1, y1, z1))))");
cnf = cnfConv.convertToCNF(origSentence);
Assert.AreEqual("[~P(x1,y1), Q(x1,y1,SF1(x1,y1))]", cnf.ToString());
// Ex.Ay.Az.(r(y,z) <=> q(x,y,z))
origSentence = parser
.parse("EXISTS x2 (FORALL y2 (FORALL z2 (R(y2, z2) <=> Q(x2, y2, z2))))");
cnf = cnfConv.convertToCNF(origSentence);
Assert.AreEqual(
"[~R(y2,z2), Q(SC1,y2,z2)],[~Q(SC1,y2,z2), R(y2,z2)]", cnf
.ToString());
// Ax.Ey.(~p(x,y) => Az.(q(x,y,z)))
origSentence = parser
.parse("FORALL x3 (EXISTS y3 (NOT(P(x3, y3)) => FORALL z3 (Q(x3, y3, z3))))");
cnf = cnfConv.convertToCNF(origSentence);
Assert
.AreEqual("[P(x3,SF2(x3)), Q(x3,SF2(x3),z3)]", cnf
.ToString());
// Ew.Ex.Ey.Ez.(r(x,y) & q(x,w,z))
origSentence = parser
.parse("NOT(EXISTS w4 (EXISTS x4 (EXISTS y4 ( EXISTS z4 (R(x4, y4) AND Q(x4, w4, z4))))))");
cnf = cnfConv.convertToCNF(origSentence);
Assert.AreEqual("[~Q(x4,w4,z4), ~R(x4,y4)]", cnf.ToString());
}
