public List <HornClauseClass> GetKB(String file)
{
List <HornClauseClass> result = new List <HornClauseClass>();
String[] fileData = System.IO.File.ReadAllLines(file);
int ClauseLine = 0;
for (int i = 0; i < fileData.Count(); i++)
{
if (fileData[i].ToUpper() == "TELL")
{
ClauseLine = i + 1;
break;
}
}
fileData[ClauseLine] = fileData[ClauseLine].Replace(" ", string.Empty);
String[] line = fileData[ClauseLine].Split(';');
foreach (String sentence in line.Where(n => n != ""))
{
HornClauseClass temp = Sentence2Clause(sentence);
if (temp != null)
{
result.Add(temp);
}
}
return(result);
}
public override string EvaluateQuery(QueryClass Query, Boolean Debug)
{
string Result = "YES:";
// initialise our goals list to the symbol(s) contained within the query
List <string> goals = Query.QueryClause.GetSymbols();
List <string> searched = new List <string>();
// starting from the symbol query, iteratively check if each symbol in the goals list
// is a conclusion of another KB clause, or is a fact.
// if the symbol is a conclusion of another KB clause, then we add the symbols of
// the premise of that clause to the goals symbols list
while (goals.Count > 0)
{
String goal = goals[0];
goals.RemoveAt(0);
searched.Add(goal);
HornClauseClass ex = isConclusionOrFact(goal);//Not sure why I called it ex. name can be changed - Thomas
if (ex == null)
{
//null should say that it wasn't a conclusion or a fact in the knowledge base
//and therefore should return null
return("NO");
}
else if (ex.GetType().Name == "HornClauseImplicationClass")
{
//probably should keep the clauses
List <String> temp = ex.GetPremiseSymbols();
foreach (String str in temp)
{
if (!goals.Contains(str) && !searched.Contains(str))
{
goals.Add(str);
}
}
}
}
searched.Reverse();
for (int i = 0; i < searched.Count; i++)
{
Result += " " + searched[i];
if (i < searched.Count - 1)
{
Result += ",";
}
}
return(Result);
}
public HornClauseAndClass(HornClauseClass Premise1, HornClauseClass Premise2)
{
this.Premise1 = Premise1;
this.Premise2 = Premise2;
this.Type = HornClauseClassType.And;
}
public HornClauseClass Premise1; // Phrases can consist of other phrases
public HornClauseBracketClass(HornClauseClass Premise1)
{
this.Premise1 = Premise1;
this.Type = HornClauseClassType.Bracket;
}
public HornClauseOrClass(HornClauseClass Premise1, HornClauseClass Premise2)
{
this.Premise1 = Premise1;
this.Premise2 = Premise2;
this.Type = HornClauseClassType.Or;
}
private HornClauseClass Sentence2Clause(String sentence)
{
/*if (sentence.Contains("("))
* {
* String[] separator = { "(" };
* String temp1 = sentence.Substring (0, sentence.IndexOf ('('));
*
* String temp2 = sentence.Substring (sentence.IndexOf ('(')+1,sentence.Length-sentence.IndexOf ('(')-1);
* String[] RHS;
*
*
* int OpenBracketCount = 0;
* int SplitIndex = 0;
*
* for (int charNum = 0; charNum < temp2.Length; charNum ++) {
* if (temp2[charNum] == ')') {
* if (OpenBracketCount == 0) {
* // we've reached the corresponding close bracket
* // save this as the SplitIndex
* SplitIndex = charNum;
* break;
* } else {
* // if not the corresponding bracket, then decrement the OpenBracketCount
* OpenBracketCount = OpenBracketCount - 1;
* }
* }
* else if(temp2[charNum] == '('){
* // then increment the OpenBracketCount
* OpenBracketCount = OpenBracketCount + 1;
* }
* }
*
* // split the left hand side and then add it
* String temp3 = temp2.Substring (0, SplitIndex);
* String temp4 = temp2.Substring (SplitIndex+1,temp2.Length-SplitIndex-1);
*
* // append the temp3 to the temp1 string
* temp1 = temp1 + temp3;
*
*
* HornClauseClass tempHorn1 = Sentence2Clause(temp1);
* HornClauseClass tempHorn2 = Sentence2Clause(temp4);
* return new HornClauseBidirectionalClass(tempHorn1, tempHorn2);
* }
* else*/if (sentence.Contains("<=>"))
{
String[] separator = { "<=>" };
String[] temp = sentence.Split(separator, System.StringSplitOptions.RemoveEmptyEntries);
HornClauseClass tempHorn1 = Sentence2Clause(temp[0]);
HornClauseClass tempHorn2 = Sentence2Clause(temp[1]);
return(new HornClauseBidirectionalClass(tempHorn1, tempHorn2));
}
else if (sentence.Contains("=>"))
{
String[] separator = { "=>" };
String[] temp = sentence.Split(separator, System.StringSplitOptions.RemoveEmptyEntries);
HornClauseClass tempHorn1 = Sentence2Clause(temp[0]);
HornClauseClass tempHorn2 = Sentence2Clause(temp[1]);
return(new HornClauseImplicationClass(tempHorn1, tempHorn2));
}
else if (sentence.Contains("\\/"))
{
String[] separator = { "\\/" };
String[] temp = sentence.Split(separator, 2, System.StringSplitOptions.RemoveEmptyEntries);
HornClauseClass tempHorn1 = Sentence2Clause(temp[0]);
HornClauseClass tempHorn2 = Sentence2Clause(temp[1]);
return(new HornClauseOrClass(tempHorn1, tempHorn2));
}
else if (sentence.Contains("&"))
{
String[] temp = sentence.Split(new char[] { '&' }, 2);
HornClauseClass tempHorn1 = Sentence2Clause(temp[0]);
HornClauseClass tempHorn2 = Sentence2Clause(temp[1]);
return(new HornClauseAndClass(tempHorn1, tempHorn2));
}
else if (sentence.Contains("~"))
{
String[] separator = { "~" };
String[] temp = sentence.Split(separator, System.StringSplitOptions.RemoveEmptyEntries);
HornClauseClass tempHorn1 = Sentence2Clause(temp [0]);
return(new HornClauseNotClass(tempHorn1));
}
else if (Regex.IsMatch(sentence, "^[a-zA-Z][a-zA-Z0-9_]*$"))
{
return(new HornClauseFactClass(sentence));
}
else
{
return(null);
}
}
public HornClauseClass Premise1; // Phrases can consist of other phrases
public HornClauseNotClass(HornClauseClass Premise1)
{
this.Premise1 = Premise1;
this.Type = HornClauseClassType.Not;
}
public HornClauseClass QueryClause; // Clause to represent the query being asked of the KB
// Methods
public QueryClass(HornClauseClass Clause)
{
this.QueryClause = Clause;
//this.InferenceType = InferenceTypeENUM.TT;
}
public HornClauseBidirectionalClass(HornClauseClass Premise1, HornClauseClass Premise2)
{
this.Premise1 = Premise1;
this.Premise2 = Premise2;
this.Type = HornClauseClassType.Biconditional;
}
public HornClauseImplicationClass(HornClauseClass Premise, HornClauseClass Conclusion)
{
this.Premise = Premise;
this.Conclusion = Conclusion;
this.Type = HornClauseClassType.Implication;
}
