/// <summary>
/// Adds the vector to the hashtable and returns any previously added tweets with the same hash value
/// </summary>
/// <param name="vector"></param>
/// <returns></returns>
public List <LSHashTweet> Add(LSHashTweet tweet, out bool anyTrue)
{
lock (accessLock)
{
CustomBitArray hash = _hashFunction.CalculateHashScore(tweet.Vector, out anyTrue);
LSHashTableCell cell;
if (_values.TryGetValue(hash, out cell))
{
List <LSHashTweet> neighbors = cell.GetTweets();
cell.Add(tweet);
_lastUpdatedCell = cell;
if (anyTrue)
{
return(neighbors);
}
return(new List <LSHashTweet>());
}
else
{
cell = new LSHashTableCell(_cellCapacity);
cell.Add(tweet);
_values.Add(hash, cell);
_lastUpdatedCell = cell;
return(new List <LSHashTweet>());
}
}
}
private static double GetNeighbors(List <TweetRelationSimple> relations, LSHashTweet t, Dictionary <LSHashTweet, int> neighborCandidates, Double maxSimilarity)
{
if (neighborCandidates.Count > 0)
{
IEnumerable <LSHashTweet> nearestCandidates = neighborCandidates
.OrderByDescending(n => n.Value) //sort by number of times the candidate was in the same bin as this tweet
.Select(n => n.Key) //select the candidates
.Take(3 * Settings.TweetClusterer_TCW_HashTableCount) //take the 3L best candidates
.OrderByDescending(n => n.Vector * t.Vector) //sort by actual similarity
.Take(Settings.TweetClusterer_TCW_MaxLinksPerTweet); //take best
foreach (LSHashTweet candidate in nearestCandidates)
{
double similarity = candidate.Vector * t.Vector;
if (similarity > maxSimilarity)
{
maxSimilarity = similarity;
}
if (similarity > Settings.TweetClusterer_TCW_MinTweetSimilarityForLink && t.ID != candidate.ID)
{
relations.Add(new TweetRelationSimple()
{
TweetID = t.ID, TweetID2 = candidate.ID, Similarity = similarity
});
}
}
}
return(maxSimilarity);
}
/// <summary>
/// Adds the vector to the hashtable and returns any previously added tweets with the same hash value
/// </summary>
/// <param name="vector"></param>
/// <returns></returns>
public List<LSHashTweet> Add(LSHashTweet tweet, out bool anyTrue)
{
lock (accessLock)
{
CustomBitArray hash = _hashFunction.CalculateHashScore(tweet.Vector, out anyTrue);
LSHashTableCell cell;
if (_values.TryGetValue(hash, out cell))
{
List<LSHashTweet> neighbors = cell.GetTweets();
cell.Add(tweet);
_lastUpdatedCell = cell;
if (anyTrue)
return neighbors;
return new List<LSHashTweet>();
}
else
{
cell = new LSHashTableCell(_cellCapacity);
cell.Add(tweet);
_values.Add(hash, cell);
_lastUpdatedCell = cell;
return new List<LSHashTweet>();
}
}
}
public List <LSHashTweet> GetNearestNeighbors(LSHashTweet tweet, int n)
{
if (_content.Count == 0)
{
return(new List <LSHashTweet>());
}
HashSet <LSHashTweet> candidates = new HashSet <LSHashTweet>();
List <long> wordIDs = tweet.Vector.GetItemIDs();
foreach (long wordID in wordIDs)
{
if (_wordIndex.ContainsKey(wordID))
{
foreach (LSHashTweet candidate in _wordIndex[wordID])
{
candidates.Add(candidate);
}
}
}
if (candidates.Count == 0)
{
return(new List <LSHashTweet>());
}
return(candidates.OrderByDescending(t => t.Vector * tweet.Vector).Take(n).ToList());
}
public void Add(LSHashTweet item)
{
_content.Enqueue(item);
if (_content.Count > Capacity)
{
_content.Dequeue();
}
}
public void Add(LSHashTweet item)
{
_content.Enqueue(item);
List<long> wordIDs = item.Vector.GetItemIDs();
foreach (long wordID in wordIDs)
{
if (!_wordIndex.ContainsKey(wordID))
_wordIndex.Add(wordID, new List<LSHashTweet>());
_wordIndex[wordID].Add(item);
}
if (_content.Count > Capacity)
RemoveOldest();
}
void RemoveOldest()
{
LSHashTweet tweet = _content.Dequeue();
List <long> wordIDs = tweet.Vector.GetItemIDs();
foreach (long wordID in wordIDs)
{
_wordIndex[wordID].Remove(tweet);
if (_wordIndex[wordID].Count == 0)
{
_wordIndex.Remove(wordID);
}
}
}
public void Add(LSHashTweet item)
{
_content.Enqueue(item);
List <long> wordIDs = item.Vector.GetItemIDs();
foreach (long wordID in wordIDs)
{
if (!_wordIndex.ContainsKey(wordID))
{
_wordIndex.Add(wordID, new List <LSHashTweet>());
}
_wordIndex[wordID].Add(item);
}
if (_content.Count > Capacity)
{
RemoveOldest();
}
}
public List<LSHashTweet> GetNearestNeighbors(LSHashTweet tweet, int n)
{
if (_content.Count == 0)
return new List<LSHashTweet>();
HashSet<LSHashTweet> candidates = new HashSet<LSHashTweet>();
List<long> wordIDs = tweet.Vector.GetItemIDs();
foreach (long wordID in wordIDs)
{
if (_wordIndex.ContainsKey(wordID))
{
foreach (LSHashTweet candidate in _wordIndex[wordID])
candidates.Add(candidate);
}
}
if (candidates.Count == 0)
return new List<LSHashTweet>();
return candidates.OrderByDescending(t => t.Vector * tweet.Vector).Take(n).ToList();
}
private Dictionary <LSHashTweet, int> GetNeighborCandidates(LSHashTweet t)
{
Dictionary <LSHashTweet, int> neighborCandidates = new Dictionary <LSHashTweet, int>();
foreach (LSHashTable table in _tables)
{
bool dummy;
List <LSHashTweet> hits = table.Add(t, out dummy);
foreach (LSHashTweet hit in hits)
{
if (neighborCandidates.ContainsKey(hit))
{
neighborCandidates[hit]++;
}
else
{
neighborCandidates.Add(hit, 1);
}
}
}
return(neighborCandidates);
}
public void Add(LSHashTweet item)
{
_content.Enqueue(item);
if (_content.Count > Capacity)
_content.Dequeue();
}
private Double GetNeighborsFromRecentHistory(List <TweetRelationSimple> relations, LSHashTweet t, Double maxSimilarity)
{
List <LSHashTweet> nearestCandidates = _history.GetNearestNeighbors(t, Settings.TweetClusterer_TCW_MaxLinksPerTweet - relations.Count);
foreach (LSHashTweet candidate in nearestCandidates)
{
double similarity = candidate.Vector * t.Vector;
if (similarity > Settings.TweetClusterer_TCW_MinTweetSimilarityForLink)
{
relations.Add(new TweetRelationSimple()
{
TweetID = t.ID, TweetID2 = candidate.ID, Similarity = similarity
});
if (similarity > maxSimilarity)
{
maxSimilarity = similarity;
}
}
}
return(maxSimilarity);
}
private Double GetNeighborsFromRecentHistory(List<TweetRelationSimple> relations, LSHashTweet t, Double maxSimilarity)
{
List<LSHashTweet> nearestCandidates = _history.GetNearestNeighbors(t, Settings.TweetClusterer_TCW_MaxLinksPerTweet - relations.Count);
foreach (LSHashTweet candidate in nearestCandidates)
{
double similarity = candidate.Vector * t.Vector;
if (similarity > Settings.TweetClusterer_TCW_MinTweetSimilarityForLink)
{
relations.Add(new TweetRelationSimple() { TweetID = t.ID, TweetID2 = candidate.ID, Similarity = similarity });
if (similarity > maxSimilarity)
maxSimilarity = similarity;
}
}
return maxSimilarity;
}
private Dictionary<LSHashTweet, int> GetNeighborCandidates(LSHashTweet t)
{
Dictionary<LSHashTweet, int> neighborCandidates = new Dictionary<LSHashTweet, int>();
foreach (LSHashTable table in _tables)
{
bool dummy;
List<LSHashTweet> hits = table.Add(t, out dummy);
foreach (LSHashTweet hit in hits)
{
if (neighborCandidates.ContainsKey(hit))
neighborCandidates[hit]++;
else
neighborCandidates.Add(hit, 1);
}
}
return neighborCandidates;
}
private static double GetNeighbors(List<TweetRelationSimple> relations, LSHashTweet t, Dictionary<LSHashTweet, int> neighborCandidates, Double maxSimilarity)
{
if (neighborCandidates.Count > 0)
{
IEnumerable<LSHashTweet> nearestCandidates = neighborCandidates
.OrderByDescending(n => n.Value) //sort by number of times the candidate was in the same bin as this tweet
.Select(n => n.Key) //select the candidates
.Take(3 * Settings.TweetClusterer_TCW_HashTableCount) //take the 3L best candidates
.OrderByDescending(n => n.Vector * t.Vector) //sort by actual similarity
.Take(Settings.TweetClusterer_TCW_MaxLinksPerTweet); //take best
foreach (LSHashTweet candidate in nearestCandidates)
{
double similarity = candidate.Vector * t.Vector;
if (similarity > maxSimilarity)
maxSimilarity = similarity;
if (similarity > Settings.TweetClusterer_TCW_MinTweetSimilarityForLink && t.ID != candidate.ID)
{
relations.Add(new TweetRelationSimple() { TweetID = t.ID, TweetID2 = candidate.ID, Similarity = similarity });
}
}
}
return maxSimilarity;
}
