/// <summary>
/// Tinh tap L tu tap F hien tai
/// </summary>
/// <param name="fCurrent"></param>
/// <returns></returns>
public static ItemSetsCollection TinhL(List <ItemSetsCollection> fCurrent)
{
ItemSetsCollection results = new ItemSetsCollection();
// Lap lay danh sach cac chi muc thuoc F
foreach (ItemSetsCollection listItemsets in fCurrent)
{
foreach (Itemsets itemsets in listItemsets)
{
results.AddItemsets(itemsets);
}
}
// Cac chi muc cua tap L thoa minSup
// Loai bo cac tap muc khong thoa minSup
ItemSetsCollection tmp1 = new ItemSetsCollection();
foreach (Itemsets i in results)
{
if (i.support >= Program.sup)
{
i.support = (float)Math.Round(((i.support) / Program.tongSoGiaoTac * 100), 2);
if (!Program.tapL.IsContains(i))
{
Program.tapL.Add(i);
}
tmp1.Add(i);
}
}
return(tmp1);
}
/// <summary>
/// Thuat toan apriori_gen, sinh ra tap ung vien C tu tap L(k-1)
/// </summary>
/// <param name="lPrevious">L(k-1)</param>
/// <returns></returns>
public static ItemSetsCollection AprioriGen(ItemSetsCollection lPrevious)
{
ItemSetsCollection result = new ItemSetsCollection();
if (lPrevious.Count <= 1)
{
return(result);
}
int k = lPrevious[0].Count;
for (int i = 0; i < lPrevious.Count - 1; i++)
{
Itemsets p = new Itemsets(lPrevious[i]);
p.RemoveAt(k - 1);
for (int j = i + 1; j < lPrevious.Count; j++)
{
Itemsets q = new Itemsets(lPrevious[j]);
q.RemoveAt(k - 1);
if (p.IsEqual(q))
{
q.Add(lPrevious[i][k - 1]);
q.Add(lPrevious[j][k - 1]);
result.Add(q);
}
}
}
return(result);
}
/// <summary>
/// Sinh ra tap F moi tu F(k-1) va L(k-1)
/// </summary>
/// <param name="fPrevious"></param>
/// <param name="lPrevious"></param>
/// <returns></returns>
public static List <ItemSetsCollection> SinhF(List <ItemSetsCollection> fPrevious, ItemSetsCollection lPrevious)
{
Program.k += 1;
ItemSetsCollection tapC = AprioriGen(lPrevious);
List <ItemSetsCollection> result = new List <ItemSetsCollection>();
foreach (ItemSetsCollection fItem in fPrevious)
{
// tid
ItemSetsCollection tmp = new ItemSetsCollection();
foreach (Itemsets item in tapC)
{
if (ThuocTid(fItem, item))
{
tmp.Add(item);
tmp.tid = fItem.tid;
}
}
if (tmp.Count > 0)
{
result.Add(tmp);
}
}
Program.tapF.Add(result);
return(result);
}
public ItemSetsCollection findSubSet()
{
ItemSetsCollection result = new ItemSetsCollection();
for (int i = 1; i < this.Count; i++)
{
result.Add(new Itemsets(this[i - 1]));
ItemSetsCollection newSubsets = new ItemSetsCollection();
for (int j = 0; j < result.Count; j++)
{
Itemsets newSubset = new Itemsets();
newSubset.AddRange(result[j]);
newSubset.Add(this[i]);
newSubsets.Add(newSubset);
}
result.AddRange(newSubsets);
}
result.Add(new Itemsets(this[this.Count - 1]));
return(result);
}
/// <summary>
/// Lap tren datatable lay tu sql server do ve, Kiem tra cac ceil co gia tri la 1 thi them vao F
/// </summary>
/// <param name="dataTable"></param>
/// <returns></returns>
public static List <ItemSetsCollection> SinhTapFTuTapD(DataTable dataTable)
{
List <ItemSetsCollection> fResults = new List <ItemSetsCollection>();
for (int i = 0; i < dataTable.Rows.Count; i++)
{
ItemSetsCollection tapCacMuc = new ItemSetsCollection();
for (int j = 1; j < dataTable.Columns.Count; j++)
{
if (dataTable.Rows[i][j].ToString().Equals("1"))
{
Itemsets muc = new Itemsets();
muc.Add(j);
tapCacMuc.Add(muc);
}
}
tapCacMuc.tid = dataTable.Rows[i][0].ToString();
fResults.Add(tapCacMuc);
}
return(fResults);
}