public FPGrowth(List <List <int> > dsp, double ms)
{
DSProcessed = dsp;
MinSupportDbl = ms;
MinSupportInt = (int)(DSProcessed.Count * MinSupportDbl);
FP_Tree = new FPTree();
L = new List <List <Item> >();
Patterns = new List <Pattern>();
}
public FPTree BuildTree(List <Pattern> ptns)
{
FPTree fptree = Preproccess(ptns);
foreach (Pattern ptn in ptns)
{
Insert(fptree.Root, ptn, fptree.HeadTable);
}
return(fptree);
}
public FPTree Preproccess(List <Pattern> ptns)//generate headtable, fptree
{
if (ptns.Count == 0)
{
return(new FPTree());
}
FPTree fptree = new FPTree();
List <int> hash = Enumerable.Repeat(0, ptns.Select(x => x.Items.Max()).Max() + 1).ToList();
//calc item count
List <List <int> > lli = ptns.Select(x => x.Items).ToList();
for (int i = 0; i < lli.Count; i++)
{
for (int j = 0; j < lli[i].Count; j++)
{
hash[lli[i][j]] += ptns[i].PtnCnt;
}
}
//generate headtable
for (int i = 0; i < hash.Count; i++)
{
if (hash[i] >= MinSupportInt)
{
fptree.HeadTable.HeadNodes.Add(new HeadNode(new Pattern(new List <int>()
{
i
}, hash[i])));
fptree.HeadTable.Count.Add(i, hash[i]);
}
}
IComparer <HeadNode> PS = new HeadNodeSorter();
fptree.HeadTable.HeadNodes.Sort(PS);
fptree.HeadTable.CalcIndex();
return(fptree);
}
