001 /*
002 * Created on Dec 8, 2004
003 *
004 */
005 package aima.test.logictest.prop.algorithms;
006
007 import java.util.Set;
008
009 import junit.framework.TestCase;
010 import aima.logic.propositional.algorithms.KnowledgeBase;
011 import aima.logic.propositional.algorithms.PLResolution;
012 import aima.logic.propositional.parsing.PEParser;
013 import aima.logic.propositional.parsing.ast.Sentence;
014 import aima.logic.propositional.parsing.ast.Symbol;
015
016 /**
017 * @author Ravi Mohan
018 *
019 */
020
021 public class PLResolutionTest extends TestCase {
022 private PLResolution resolution;
023
024 private PEParser parser;
025
026 @Override
027 public void setUp() {
028 resolution = new PLResolution();
029 parser = new PEParser();
030 }
031
032 public void testPLResolveWithOneLiteralMatching() {
033 Sentence one = (Sentence) parser.parse("(A OR B)");
034 Sentence two = (Sentence) parser.parse("((NOT B) OR C)");
035 Sentence expected = (Sentence) parser.parse("(A OR C)");
036 Set resolvents = resolution.plResolve(one, two);
037 assertEquals(1, resolvents.size());
038 assertTrue(resolvents.contains(expected));
039 }
040
041 public void testPLResolveWithNoLiteralMatching() {
042 Sentence one = (Sentence) parser.parse("(A OR B)");
043 Sentence two = (Sentence) parser.parse("(C OR D)");
044 Set resolvents = resolution.plResolve(one, two);
045 assertEquals(0, resolvents.size());
046 }
047
048 public void testPLResolveWithOneLiteralSentencesMatching() {
049 Sentence one = (Sentence) parser.parse("A");
050 Sentence two = (Sentence) parser.parse("(NOT A)");
051 // Sentence expected =(Sentence) parser.parse("(A OR C)");
052 Set resolvents = resolution.plResolve(one, two);
053 assertEquals(1, resolvents.size());
054 assertTrue(resolvents.contains(new Symbol("EMPTY_CLAUSE")));
055 }
056
057 public void testPLResolveWithTwoLiteralsMatching() {
058 Sentence one = (Sentence) parser.parse("((NOT P21) OR B11)");
059 Sentence two = (Sentence) parser.parse("(((NOT B11) OR P21) OR P12)");
060 Sentence expected1 = (Sentence) parser
061 .parse("( ( P12 OR P21 ) OR ( NOT P21 ) )");
062 Sentence expected2 = (Sentence) parser
063 .parse("( ( B11 OR P12 ) OR ( NOT B11 ) )");
064 Set resolvents = resolution.plResolve(one, two);
065
066 assertEquals(2, resolvents.size());
067 assertTrue(resolvents.contains(expected1));
068 assertTrue(resolvents.contains(expected2));
069 }
070
071 public void testPLResolve1() {
072 boolean b = resolution.plResolution("((B11 => (NOT P11)) AND B11)",
073 "(P11)");
074 assertEquals(false, b);
075 }
076
077 public void testPLResolve2() {
078 boolean b = resolution.plResolution("(A AND B)", "B");
079 assertEquals(true, b);
080 }
081
082 public void testPLResolve3() {
083 boolean b = resolution.plResolution("((B11 => (NOT P11)) AND B11)",
084 "(NOT P11)");
085 assertEquals(true, b);
086 }
087
088 public void testPLResolve4() {
089 boolean b = resolution.plResolution("(A OR B)", "B");
090 assertEquals(false, b);
091 }
092
093 public void testPLResolve5() {
094 boolean b = resolution.plResolution("((B11 => (NOT P11)) AND B11)",
095 "(NOT B11)");
096 assertEquals(false, b);
097 }
098
099 public void testMultipleClauseResolution() {
100 // test (and fix) suggested by Huy Dinh. Thanks Huy!
101 PLResolution plr = new PLResolution();
102 KnowledgeBase kb = new KnowledgeBase();
103 String fact = "((B11 <=> (P12 OR P21)) AND (NOT B11))";
104 kb.tell(fact);
105 plr.plResolution(kb, "(B)");
106
107 }
108
109 // public void testPLResolutionWithChadCarfBugReportData() {
110 // commented out coz this needs a major fix wait for a rewrite
111 // KnowledgeBase kb = new KnowledgeBase();
112 // kb.tell("(B12 <=> (P11 OR (P13 OR (P22 OR P02))))");
113 // kb.tell("(B21 <=> (P20 OR (P22 OR (P31 OR P11))))");
114 // kb.tell("(B01 <=> (P00 OR (P02 OR P11)))");
115 // kb.tell("(B10 <=> (P11 OR (P20 OR P00)))");
116 // kb.tell("(NOT B21)");
117 // kb.tell("(NOT B12)");
118 // kb.tell("(B10)");
119 // kb.tell("(B01)");
120 // assertTrue(resolution.plResolution(kb.asSentence().toString(), "(P00)"));
121 // //assertFalse(kb.askWithDpll("(NOT P00)"));
122 //
123 //
124 // }
125
126 }