public void SetNewHashFunction(LSHashFunction hashFunction)
{
lock (accessLock)
{
Dictionary <CustomBitArray, LSHashTableCell> oldValues = _values;
_values = new Dictionary <CustomBitArray, LSHashTableCell>();
_hashFunction = hashFunction;
//Re-hash all the old tweets using the new hash function
foreach (LSHashTableCell oldCell in oldValues.Values)
{
foreach (LSHashTweet tweet in oldCell.GetTweets())
{
bool anyTrue = false;
CustomBitArray hash = _hashFunction.CalculateHashScore(tweet.Vector, out anyTrue);
LSHashTableCell cell;
if (_values.TryGetValue(hash, out cell))
{
cell.Add(tweet);
}
else
{
cell = new LSHashTableCell(_cellCapacity);
cell.Add(tweet);
_values.Add(hash, cell);
}
}
}
}
}
public void SetNewHashFunction(LSHashFunction hashFunction)
{
lock (accessLock)
{
Dictionary<CustomBitArray, LSHashTableCell> oldValues = _values;
_values = new Dictionary<CustomBitArray, LSHashTableCell>();
_hashFunction = hashFunction;
//Re-hash all the old tweets using the new hash function
foreach (LSHashTableCell oldCell in oldValues.Values)
{
foreach (LSHashTweet tweet in oldCell.GetTweets())
{
bool anyTrue = false;
CustomBitArray hash = _hashFunction.CalculateHashScore(tweet.Vector, out anyTrue);
LSHashTableCell cell;
if (_values.TryGetValue(hash, out cell))
{
cell.Add(tweet);
}
else
{
cell = new LSHashTableCell(_cellCapacity);
cell.Add(tweet);
_values.Add(hash, cell);
}
}
}
}
}
/// <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>());
}
}
}