public virtual void Build(MetricDB db, int width, Random rand, Func<InvertedIndex,InvertedIndex> create_invertedindex = null, Func<int,object> get_item = null)
{
this.DB = db;
this.Width = width;
int len = this.DB.Count;
int pc = len / 100 + 1;
int numbits = width > 32 ? 32 : width;
Plain64InvertedIndex table = new Plain64InvertedIndex ();
table.Initialize (1 << numbits);
int maxhash = 0;
this.PreBuild (rand, this.DB [0]);
for (int objID = 0; objID < len; objID++) {
if (objID % pc == 0) {
Console.WriteLine ("Advance: {0:0.00}%, docid: {1}, total: {2}", objID * 100.0 / len, objID, len);
}
int hash;
if (get_item == null) {
hash = this.ComputeHash (this.DB [objID]);
} else {
hash = this.ComputeHash (get_item (objID));
}
table.AddItem(hash, objID);
if (hash > maxhash) {
maxhash = hash;
}
}
table.Trim (maxhash + 1);
if (create_invertedindex == null) {
this.invindex = table;
} else {
this.invindex = create_invertedindex (table);
}
}
public static Plain64InvertedIndex Build(InvertedIndex invindex)
{
var I = new Plain64InvertedIndex ();
for (int i = 0; i < invindex.Count; ++i) {
I.Add (invindex[i]);
}
return I;
}