001 package aima.learning.knowledge;
002
003 import java.util.ArrayList;
004 import java.util.List;
005
006 import aima.learning.framework.Example;
007 import aima.logic.fol.Connectors;
008 import aima.logic.fol.parsing.ast.ConnectedSentence;
009 import aima.logic.fol.parsing.ast.Constant;
010 import aima.logic.fol.parsing.ast.NotSentence;
011 import aima.logic.fol.parsing.ast.Predicate;
012 import aima.logic.fol.parsing.ast.Sentence;
013 import aima.logic.fol.parsing.ast.Term;
014
015 /**
016 * @author Ciaran O'Reilly
017 *
018 */
019 public class FOLExample {
020 private FOLDataSetDomain folDSDomain = null;
021 private Example example = null;
022 private int egNo = 0;
023 //
024 private Constant ithExampleConstant = null;
025 private Sentence classification = null;
026 private Sentence description = null;
027
028 //
029 // PUBLIC METHODS
030 //
031 public FOLExample(FOLDataSetDomain folDSDomain, Example example, int egNo) {
032 this.folDSDomain = folDSDomain;
033 this.example = example;
034 this.egNo = egNo;
035 constructFOLEg();
036 }
037
038 public int getExampleNumber() {
039 return egNo;
040 }
041
042 public Sentence getClassification() {
043 return classification;
044 }
045
046 public Sentence getDescription() {
047 return description;
048 }
049
050 public String toString() {
051 return classification.toString() + " " + Connectors.AND + " " + description.toString();
052 }
053
054 //
055 // PRIVATE METHODS
056 //
057 private void constructFOLEg() {
058 ithExampleConstant = new Constant(folDSDomain.getExampleConstant(egNo));
059
060 List<Term> terms = new ArrayList<Term>();
061 terms.add(ithExampleConstant);
062 // Create the classification sentence
063 classification = new Predicate(folDSDomain.getGoalPredicateName(), terms);
064 if (!example.getAttributeValueAsString(
065 folDSDomain.getDataSetTargetName()).equals(
066 folDSDomain.getTrueGoalValue())) {
067 // if not true then needs to be a Not sentence
068 classification = new NotSentence(classification);
069 }
070
071 // Create the description sentence
072 List<Sentence> descParts = new ArrayList<Sentence>();
073 for (String dname : folDSDomain.getDescriptionDataSetNames()) {
074 String foldDName = folDSDomain.getFOLName(dname);
075 terms = new ArrayList<Term>();
076 terms.add(ithExampleConstant);
077 // If multivalued becomes a two place predicate
078 // e.g: Patrons(X1, Some)
079 // otherwise: Hungry(X1) or ~ Hungry(X1)
080 // see pg 679 of AIMA
081 Sentence part = null;
082 if (folDSDomain.isMultivalued(dname)) {
083 terms.add(new Constant(folDSDomain.getFOLName(example.getAttributeValueAsString(dname))));
084 part = new Predicate(foldDName, terms);
085 } else {
086 part = new Predicate(foldDName, terms);
087 // Need to determine if false
088 if (!folDSDomain.getTrueGoalValue().equals(example.getAttributeValueAsString(dname))) {
089 part = new NotSentence(part);
090 }
091 }
092 descParts.add(part);
093 }
094 if (descParts.size() == 1) {
095 description = descParts.get(0);
096 } else if (descParts.size() > 1) {
097 description = new ConnectedSentence(Connectors.AND, descParts.get(0), descParts.get(1));
098 for (int i = 2; i < descParts.size(); i++) {
099 description = new ConnectedSentence(Connectors.AND, description, descParts.get(i));
100 }
101 }
102 }
103 }