protected virtual void ComputeDistRow(DynamicSequentialOrdered idxseq, Random rand, HashSet<int> already_pivot, List<EPivot> pivs, List<ItemPair> _items)
{
_items.Clear ();
int n = idxseq.DB.Count;
int piv;
do {
piv = rand.Next(0, n);
} while (already_pivot.Contains(piv));
already_pivot.Add (piv);
var stats = new DynamicSequential.Stats ();
idxseq.ComputeDistances (idxseq.DB [piv], _items, out stats);
int pivID = pivs.Count;
pivs.Add(new EPivot(piv, stats.stddev, stats.mean, stats.min, stats.max, 0, 0));
if (this.Items == null) {
this.Items = new ItemPair[n];
for (int objID = 0; objID < n; ++objID) {
this.Items[objID] = new ItemPair(0, _items[objID].Dist);
}
} else {
for (int objID = 0; objID < n; ++objID) {
var new_piv = pivs[pivID];
var new_dist = _items[objID].Dist;
var old_piv = pivs[ this.Items[objID].ObjID ];
var old_dist = this.Items[objID].Dist;
if (Math.Abs(old_dist - old_piv.mean) < Math.Abs (new_dist - new_piv.mean)) {
this.Items[objID] = new ItemPair(pivID, _items[objID].Dist);
}
}
}
}
protected virtual DynamicSequential.Stats ComputeDistRow(int piv, DynamicSequentialOrdered idxseq, Random rand, List<EPivot> pivs, List<ItemPair> _items)
{
_items.Clear ();
int n = idxseq.DB.Count;
var stats = new DynamicSequential.Stats ();
idxseq.ComputeDistances (idxseq.DB [piv], _items, out stats);
int pivID = pivs.Count;
pivs.Add(new EPivot(piv, stats.stddev, stats.mean, stats.min, stats.max, 0, 0));
if (this.Items == null) {
this.Items = new ItemPair[n];
for (int objID = 0; objID < n; ++objID) {
this.Items[objID] = new ItemPair(0, _items[objID].Dist);
}
} else {
for (int objID = 0; objID < n; ++objID) {
var new_piv = pivs[pivID];
var new_dist = _items[objID].Dist;
var old_piv = pivs[ this.Items[objID].ObjID ];
var old_dist = this.Items[objID].Dist;
if (Math.Abs(old_dist - old_piv.mean) < Math.Abs (new_dist - new_piv.mean)) {
this.Items[objID] = new ItemPair(pivID, _items[objID].Dist);
}
}
}
return stats;
}