public List <SearchResult> ExecuteTfIdfSearch(int?windowSize = null, byte?filterByClass = null)
{
var idfs = Query.Select(x => (token: x, idf: Index.Idf(x))).ToDictionary(x => x.token, x => x.idf);
var queryVector = new TfIdfVector(idfs, QueryTokenCounts);
var docIds = new HashSet <int>();
foreach (var token in Query)
{
foreach (var docId in Index.SearchByToken(token))
{
docIds.Add(docId);
}
}
if (windowSize.HasValue)
{
docIds = ProximityFilter(docIds, windowSize.Value);
}
var scoresByDocId = new Dictionary <int, double>();
foreach (var docId in docIds)
{
var tfByToken = new Dictionary <string, int>();
foreach (var token in Query)
{
tfByToken.Add(token, Index.GetOccurrence(token, docId).Positions.Count);
}
var docVector = new TfIdfVector(idfs, tfByToken);
scoresByDocId.Add(docId, docVector.Multiply(queryVector));
}
if (filterByClass == null)
{
return(scoresByDocId.OrderByDescending(x => x.Value).Select(x => new SearchResult(x.Key, Index.GetHighlight(x.Key), x.Value)).ToList());
}
var documents = docIds.Select(x => new DocumentWrapper(Index.PureDocumentsById[x])).ToDictionary(x => x.Document.Id);
var vectorGenerator = new VectorGenerator(documents, true);
vectorGenerator.Process();
var tokenMapper = new TokenMapper();
var classifier = new RandomForestClassifierClient();
var result = classifier.Classify(documents.Values.Select(x => x.CreateClassificationVector(tokenMapper)).ToList());
for (int i = 0; i < result.Count; i++)
{
documents.Values.ElementAt(i).ClassifiedTag = result[i];
}
var filteredResult = scoresByDocId.Where(x => documents[x.Key].ClassifiedTag == filterByClass).ToList();
Console.WriteLine($"Removed {filteredResult.Count} items with other classes");
return(filteredResult.OrderByDescending(x => x.Value).Select(x => new SearchResult(x.Key, Index.GetHighlight(x.Key), x.Value)).ToList());
}
internal void ConvertTokenToId(TokenMapper mapper)
{
IntVector = new Dictionary <int, double>();
foreach (var item in FinalVector)
{
IntVector.Add(mapper.GetOrCreateId(item.Key), item.Value);
}
}
