/// <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);
}
public Itemsets Remove(Itemsets itemsets)
{
Itemsets removed = new Itemsets();
foreach (int item in this)
{
if (!itemsets.Contains(item))
{
removed.Add(item);
}
}
//removed.AddRange(from item in thiswhere !itemsets.Contains(item)select item);
return(removed);
}
/// <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);
}
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);
}
