/// <summary>
/// 对当前候选集中的项集求support counting
/// </summary>
/// <param name="candidate">候选项集</param>
/// <param name="depth">当前的候选项集的项的个数</param>
/// <returns>返回support counting大于等于minsup的项集</returns>
static Candidates<int> DoSupportCounting(Candidates<int> candidate, int depth)
{
//建立hash树
HashTree<int> tree = new HashTree<int>(HashCode, 0, 2, depth, NodePrint);
foreach (var tmp in candidate.ItemSets)
{
tree.AddNode(tmp);
}
//计算候选集中的support counting
foreach (var tmp in transactions)
{
tree.ClearTag(tree.Root);
tree.SupportCounting(tmp, tree.Root, -1);
}
//将support counting大于minsup的加入频繁项的集合
Candidates<int> tmpCandi = new Candidates<int>();
tree.ClearTag(tree.Root);
TreeNode<int> node = tree.GetLeaves(tree.Root);
while (node != null)
{
foreach (var d in node.list)
{
if (d.value >= minsup * transactions.Count()) tmpCandi.AddCandidate(d);
}
node = tree.GetLeaves(tree.Root);
}
return SortInTrie(tmpCandi);
}