public Resource(ulong __resourceID, Constants.ResourceType __type, uint __tokens, long __size,
string __description, string __name, string __location, InformationEntropy[] __IE, object __data)
{
header = new ResourceHeader(__resourceID, __type, __tokens, __size, __description, __name, __location);
IE = __IE;
data = __data;
}
public static string Detokenize(InformationEntropy[] IEList, char delimeter)
{
string IEString = "";
foreach (InformationEntropy IE in IEList)
{
IEString += delimeter + IE.keyword;
}
return IEString;
}
public static string[] InformationEntropyToStringArray(InformationEntropy[] IEList)
{
string[] array = new string[IEList.Length];
int index = 0;
foreach (InformationEntropy IE in IEList)
{
array[index++] = IE.keyword;
}
return array;
}
public float calculateScore(string[] query, InformationEntropy[] IEs)
{
float score = 0.0f;
foreach (String keyword in query)
{
foreach (InformationEntropy IE in IEs)
{
score += queryProcessor.calculateSimilarity(keyword, IE.keyword);
}
}
//normalize to the query length
return (score/ query.Length);
}
public Peer(Node __node, PublicUserInfo __userInfo, InformationEntropy[] __IE)
{
node = __node;
userInfo = __userInfo;
IE = __IE;
}
private void finalizeResourcesIndex()
{
IDictionaryEnumerator enumerator = resourcesIndex.getEnumerator();
calculatedIE = new InformationEntropy[resourcesIndex.Count > Constants.MAX_INFORMATION_ENTROPY_LENGTH ?
Constants.MAX_INFORMATION_ENTROPY_LENGTH : resourcesIndex.Count];
int IECounter = 0;
while(enumerator.MoveNext())
{
RRLib.SortedList invertedList = (RRLib.SortedList)enumerator.Value;
int dfk = invertedList.Count;
int N = resourcesIndex.Count;
float IDFk = (float)Math.Log(N/dfk, 10);
foreach (ResourceDescriptor rd in invertedList)
{
rd.weight *= IDFk; //finish the weight calculation.
}
//Calculate our Information Entropy (top keywords)
Accumulate(calculatedIE, IECounter++, IDFk, (string)enumerator.Key);
}
}
/// <summary>
/// Accumulates the top keywords (those with most frequency) to establish as our ring's IE.
/// Uses the Binary Insertion Algorithm
/// </summary>
/// <param name="IEList"></param>
/// <param name="frequency"></param>
/// <param name="keyword"></param>
private void Accumulate(InformationEntropy [] IEList, int position, float weight, string keyword)
{
InformationEntropy IE = new InformationEntropy(keyword, weight);
bool done = false;
int index = position;
int endIndex = position;
int beginIndex = 0;
int comparison = -1;
bool evict = false;
bool headInsert = false;
if (position >= IEList.Length)
{
endIndex = IEList.Length;
position = IEList.Length;
evict = true;
}
while(!done)
{
//only if we are full calculate comparison index and do actual comparing
if (evict)
{
index = beginIndex + (endIndex - beginIndex)/2;
comparison = IE.CompareTo(IEList[index]);
}
else
headInsert = true;
if (comparison == 0 || headInsert)
{
if (!evict && IEList[index] != null)
LibUtil.ShiftArrayItems(IEList, index, position -index, 1);
IEList[index] = IE;
done = true;
}
else if (comparison < 0)
{
//if less than the last element just ignore it
if (index == IEList.Length-1)
done = true;
else
beginIndex = index;
}
else if (comparison > 0)
{
//if greater than the first element just ignore it
if (index == 0)
headInsert = true;
else
endIndex = index;
}
}
}
private static InformationEntropy[] extractInformationEntropy_internal(string text)
{
//REVISIT: reduce the # copies
string[] tokens = text.Split(Constants.TOKENIZER_DELIMETERS);
//add stopword check
Hashtable keywords = new Hashtable();
int frequency;
object freqObj;
string keyword;
foreach (string newKeyword in tokens)
{
keyword = newKeyword.ToLower();
if (keyword.Equals(""))
continue;
freqObj = keywords[keyword];
if (freqObj == null)
keywords[keyword] = 1;
else
{
frequency = ((int)freqObj);
keywords[keyword] = ++frequency;
}
}
IDictionaryEnumerator enumerator = keywords.GetEnumerator();
InformationEntropy[] ret_IE = new InformationEntropy[keywords.Count];
int insertIndex = 0;
while (enumerator.MoveNext())
{
ret_IE[insertIndex++] = new InformationEntropy((string)enumerator.Key, (float)((int)enumerator.Value));
}
return ret_IE;
}