public ISimpleItemset GetItemset(Itemset i)
{
//return (Itemset)dualStruct[i];
return(dualStruct[i.GetItem(0), i.GetItem(1)]);
}
void RecurseMining(Itemset head, List <int> tail, int support, int minLength, int maxLength, int maxGroupLength, MineResults mineResult)
{
Itemset newHead;
List <int> newTail;
if (head.Count >= maxLength)
{
return;
}
for (int loopTail = 0; loopTail < tail.Count; loopTail++)
{
int i = tail[loopTail];
if (head.Count == 0)
{
newTail = new List <int>(tail);
newTail.RemoveAt(loopTail);
newHead = new Itemset();
newHead.AddItem(i);
newHead.itemGroup[newHead.Count - 1] = 1;
newHead.groupLength = 1;
RecurseMining(newHead, newTail, support, minLength, maxLength, maxGroupLength, mineResult);
}
else
{
int currentItemGroup = head.itemGroup[head.Count - 1];
for (int loopGroups = 0; loopGroups < 2; loopGroups++)
{
// Don't try to add the same item to the same group twice
if ((loopGroups == 0) && (i < head.GetItem(head.Count - 1)))
{
continue;
}
// Don't create too long group
if ((loopGroups == 0) && (head.groupLength >= maxGroupLength))
{
continue;
}
// Add 0 / 1 depends on the loop
int newItemGroup = currentItemGroup + loopGroups;
FastSparseBitArray bitArray = null;
// Perform AND with all previous group members - calc support
for (int loopHead = 0; loopHead < head.Count; loopHead++)
{
if (head.itemGroup[loopHead] == newItemGroup - 1)
{
if (bitArray == null)
{
bitArray = _dualComp.GetItemset(head.GetItem(loopHead), i).GetTransactions();
}
else
{
bitArray = bitArray.And(_dualComp.GetItemset(head.GetItem(loopHead), i).GetTransactions());
}
}
}
if (currentItemGroup > 1)
{
bitArray = bitArray.And(head.GetTransactions());
}
bool validSupport = false;
if (bitArray == null)
{
validSupport = true;
}
else if (bitArray.CountElements() >= support)
{
validSupport = true;
}
if (validSupport == false)
{
tail.RemoveAt(loopTail);
loopTail--;
break;
}
else //if (validSupport == true)
{
newTail = new List <int>(tail);
newTail.RemoveAt(loopTail);
newHead = new Itemset(head);
newHead.AddItem(i);
newHead.itemGroup[newHead.Count - 1] = newItemGroup;
if (loopGroups == 0)
{
newHead.groupLength = head.groupLength + 1;
}
else
{
newHead.groupLength = 1;
}
newHead.SetTransactions(bitArray);
if (bitArray != null)
{
newHead.support = bitArray.CountElements();
}
RecurseMining(newHead, newTail, support, minLength, maxLength, maxGroupLength, mineResult);
// Add the new item as 'found' itemset only if 1. it's above minSupport, 2. it contains more then the first group
if ((newHead.Count >= minLength) && (newHead.Count > newHead.groupLength))
{
mineResult.Add(newHead);
}
newHead.SetTransactions(null);
}
}
}
}
}
// Mine with skip-errors
void RecurseMining(Itemset head, List <int> tail, int minSupport, int minLength, int maxLength, int maxMistakes, MineResults mineResult)
{
Itemset newHead;
List <int> newTail;
MistakesBitMask mistakes;
if (head.Count >= maxLength)
{
return;
}
List <FastSparseBitArray> newSupportVectorBitMask = new List <FastSparseBitArray>();
List <MistakesBitMask> newBitMask = new List <MistakesBitMask>();
List <int> newSupport = new List <int>();
for (int loopTail = 0; loopTail < tail.Count; loopTail++)
{
int i = tail[loopTail];
mistakes = new MistakesBitMask(maxMistakes);
FastSparseBitArray bitArray = _dualComp.GetItemset(head.GetLastItem(), i).GetTransactions();
mistakes.mistakes[0] = bitArray;
if (head.Count > 1)
{
FastSparseBitArray bitMaskTwoBack = _dualComp.GetItemset(head.GetItem(head.Count - 2), i).GetTransactions();
MistakesBitMask existingMistakes = head.GetMistakes();
mistakes.mistakes[0] = mistakes.mistakes[0].And(existingMistakes.mistakes[0]);
// ************* Build candidate **************
// Build the mistakes array
for (int loopMistakes = 1; loopMistakes < maxMistakes + 1; loopMistakes++)
{
if (existingMistakes.mistakes[loopMistakes] != null)
{
FastSparseBitArray noNewErrors = bitArray.And(existingMistakes.mistakes[loopMistakes]);
FastSparseBitArray newError = noNewErrors; // = head.GetParent().GetMistakes().mistakes[loopMistakes - 1].And(bitMaskTwoBack);
int upwardCount = 1;
Itemset upwardTraversal = head;
upwardTraversal = upwardTraversal.GetParent();
while ((upwardTraversal != null) && (loopMistakes - upwardCount >= 0))
{
FastSparseBitArray bitTIDs = _dualComp.GetItemset(upwardTraversal.GetLastItem(), i).GetTransactions();
newError = newError.Or(upwardTraversal.GetMistakes().mistakes[loopMistakes - upwardCount].And(bitTIDs));
upwardTraversal = upwardTraversal.GetParent();
upwardCount++;
}
mistakes.mistakes[loopMistakes] = newError; //.Or(noNewErrors);
}
else
{
FastSparseBitArray bitTIDs;
Itemset ancestor = head;
FastSparseBitArray newError = bitArray;
while (ancestor.GetParent() != null)
{
ancestor = ancestor.GetParent();
bitTIDs = _dualComp.GetItemset(ancestor.GetLastItem(), i).GetTransactions();
newError = newError.Or(bitTIDs);
}
mistakes.mistakes[loopMistakes] = newError; //.Or(noNewErrors);
break;
}
}
}
// *********** Calculate the support *************
int support = 999999;
// The support is the Union of the last 'maxMistakes' mistakes
// vectors, to get the last mistakes vector the algorithm preforms
// a traversal backword on the last items developed (backtracks the DFS)
FastSparseBitArray currentSupportVector = mistakes.mistakes[maxMistakes];
if (currentSupportVector != null)
{
Itemset upwardTraversal = head;
for (int upward = 0; upward < maxMistakes; upward++)
{
if (upwardTraversal == null)
{
break;
}
currentSupportVector = currentSupportVector.Or(upwardTraversal.GetMistakes().mistakes[maxMistakes - upward - 1]);
upwardTraversal = upwardTraversal.GetParent();
}
if (upwardTraversal != null)
{
support = currentSupportVector.CountElements();
}
}
if (support >= minSupport)
{
newSupportVectorBitMask.Add(currentSupportVector);
newBitMask.Add(mistakes);
newSupport.Add(support);
}
else // Just remove the item as it will not be a memeber later...
{
tail.RemoveAt(loopTail);
loopTail--;
}
}
// Do Recurse call
if (head.Count > 0)
{
for (int loopTail = 0; loopTail < tail.Count; loopTail++)
{
int i = tail[loopTail];
newTail = new List <int>(tail);
newTail.RemoveAt(loopTail);
newHead = new Itemset(head);
newHead.AddItem(tail[loopTail]);
newHead.support = newSupport[loopTail];
newHead.SetTransactions((Utils.FastSparseBitArray)newSupportVectorBitMask[loopTail]);
newHead.SetMistakes((MistakesBitMask)newBitMask[loopTail]);
newHead.SetParent(head);
RecurseMining(newHead, newTail, minSupport, minLength, maxLength, maxMistakes, mineResult);
if (newHead.Count >= minLength)
{
mineResult.Add(newHead);
/*
* System.IO.FileStream fs = new System.IO.FileStream("res.txt",
* System.IO.FileMode.Append);
* System.IO.StreamWriter tw = new System.IO.StreamWriter(fs);
* tw.WriteLine(newHead.ToString());
* tw.Close();
* fs.Close();
*/
}
newHead.SetParent(null);
newHead.SetMistakes(null);
newHead.SetTransactions(null);
}
}
}
