private static List <int> DocumentsOccuredInQuery(WordsVector wordsVector, Vector queryVector)
{
List <int> documents = new List <int>();
foreach (var pair in queryVector.Dictionary)
{
var key = pair.Key;
if (wordsVector.GetVector().ContainsKey(key))
{
var newDocuments = wordsVector.GetVector()[key].GetDocuments();
documents = AddDocuments(documents, newDocuments);
}
}
return(documents);
}
private static Vector ComputeQueryTfIdfVector(string query, WordsVector wordsVector, int totalDocuments)
{
Vector vector = new Vector(query);
foreach (var pair in vector.Dictionary)
{
var key = pair.Key;
double inverseDocumentFrequency = 0;
if (wordsVector.GetVector().ContainsKey(key))
{
var documentFrequency = wordsVector.GetVector()[key].DocumentCount;
inverseDocumentFrequency = Math.Log10(documentFrequency) / totalDocuments;
}
vector.Dictionary[key].Count *= inverseDocumentFrequency;
}
return(vector);
}
public static IList <int> Parse(string query, WordsVector wordsVector)
{
var ProximityQueryRegex = new Regex(@"^(\w+)\s(\w+)\s*/\s*(\d+)$");
var groups = ProximityQueryRegex.Match(query).Groups;
var operand1 = groups[1].Value;
var operand2 = groups[2].Value;
var displacement = Convert.ToInt32(groups[3].Value);
List <int> answer = new List <int>();
try
{
var document1 = wordsVector.GetVector()[operand1];
var document2 = wordsVector.GetVector()[operand2];
var commonDocuments = document1.GetDocuments();
commonDocuments.IntersectWith(document2.GetDocuments());
foreach (int doc in commonDocuments)
{
var list1 = document1.DocumentsDictionary[doc].Positions;
var list2 = document2.DocumentsDictionary[doc].Positions;
foreach (var position in list1)
{
if (list2.Contains(position + displacement) || list2.Contains(position - displacement))
{
answer.Add(doc);
break;
}
}
}
answer.Sort();
return(answer);
}
catch
{
return(new List <int>());
}
}
public static IList <int> Parse(string query, HashSet <int> universalSet, WordsVector wordsVector)
{
var PostfixQuery = InfixToPostfixConvertor.Convert(query);
Stack <HashSet <int> > stack = new Stack <HashSet <int> >();
foreach (var item in PostfixQuery)
{
if (item == "!")
{
var operand = stack.Pop();
var remaining = new HashSet <int>(universalSet);
remaining.ExceptWith(operand);
stack.Push(remaining);
}
else if (item == "&")
{
var operand1 = stack.Pop();
var operand2 = stack.Pop();
operand1.IntersectWith(operand2);
stack.Push(operand1);
}
else if (item == "|")
{
var operand1 = stack.Pop();
var operand2 = stack.Pop();
operand1.UnionWith(operand2);
stack.Push(operand1);
}
else
{
try
{
var documents = wordsVector.GetVector()[item].GetDocuments();
stack.Push(documents);
} catch
{
stack.Push(new HashSet <int>());
}
}
}
var answer = stack.Pop().ToList();
answer.Sort();
return(answer);
}
