void ANNbruteForce::annkSearch( // approx k near neighbor search
ANNpoint q, // query point
int k, // number of near neighbors to return
ANNidxArray nn_idx, // nearest neighbor indices (returned)
ANNdistArray dd, // dist to near neighbors (returned)
double eps) // error bound (ignored)
{
ANNmin_k mk(k); // construct a k-limited priority queue
int i;
if (k > n_pts) { // too many near neighbors?
annError("Requesting more near neighbors than data points", ANNabort);
}
// run every point through queue
for (i = 0; i < n_pts; i++) {
// compute distance to point
ANNdist sqDist = annDist(dim, pts[i], q);
if (ANN_ALLOW_SELF_MATCH || sqDist != 0)
mk.insert(sqDist, i);
}
for (i = 0; i < k; i++) { // extract the k closest points
dd[i] = mk.ith_smallest_key(i);
nn_idx[i] = mk.ith_smallest_info(i);
}
}
ANNkd_tree::ANNkd_tree( // construct from point array
ANNpointArray pa, // point array (with at least n pts)
int n, // number of points
int dd, // dimension
int bs, // bucket size
ANNsplitRule split) // splitting method
{
SkeletonTree(n, dd, bs); // set up the basic stuff
pts = pa; // where the points are
actual_num_points = n;
if (n == 0) return; // no points--no sweat
ANNorthRect bnd_box(dd); // bounding box for points
annEnclRect(pa, pidx, n, dd, bnd_box);// construct bounding rectangle
// copy to tree structure
bnd_box_lo = annCopyPt(dd, bnd_box.lo);
bnd_box_hi = annCopyPt(dd, bnd_box.hi);
switch (split) { // build by rule
case ANN_KD_STD: // standard kd-splitting rule
root = rkd_tree(pa, pidx, n, dd, bs, bnd_box, kd_split, &pointToLeafVec);
break;
case ANN_KD_MIDPT: // midpoint split
root = rkd_tree(pa, pidx, n, dd, bs, bnd_box, midpt_split, &pointToLeafVec);
break;
case ANN_KD_FAIR: // fair split
root = rkd_tree(pa, pidx, n, dd, bs, bnd_box, fair_split, &pointToLeafVec);
break;
case ANN_KD_SUGGEST: // best (in our opinion)
case ANN_KD_SL_MIDPT: // sliding midpoint split
root = rkd_tree(pa, pidx, n, dd, bs, bnd_box, sl_midpt_split, &pointToLeafVec);
break;
case ANN_KD_SL_FAIR: // sliding fair split
root = rkd_tree(pa, pidx, n, dd, bs, bnd_box, sl_fair_split, &pointToLeafVec);
break;
// for kd-trees with deletion
/*
//case ANN_KD_SUGGEST:
case ANN_KD_STD_WD:
root = rkd_tree_wd(pa, pidx, n, dd, bs, bnd_box, kd_split_wd);
break;
case ANN_KD_MIDPT_WD:
root = rkd_tree_wd(pa, pidx, n, dd, bs, bnd_box, kd_split_wd);
break;
case ANN_KD_SL_MIDPT_WD:
root = rkd_tree_wd(pa, pidx, n, dd, bs, bnd_box, kd_split_wd);
break;
*/
default:
annError("Illegal splitting method", ANNabort);
}
}
ANNbd_tree::ANNbd_tree( // construct from point array
ES_INFO* es_info,
ANNpointArray pa, // point array (with at least n pts)
int n, // number of points
int dd, // dimension
int bs, // bucket size
ANNsplitRule split, // splitting rule
ANNshrinkRule shrink) // shrinking rule
: ANNkd_tree(n, dd, bs) // build skeleton base tree
{
pts = pa; // where the points are
if (n == 0) return; // no points--no sweat
ANNorthRect bnd_box(dd); // bounding box for points
// construct bounding rectangle
annEnclRect(es_info, pa, pidx, n, dd, bnd_box);
// copy to tree structure
bnd_box_lo = annCopyPt(dd, bnd_box.lo);
bnd_box_hi = annCopyPt(dd, bnd_box.hi);
switch (split) { // build by rule
case ANN_KD_STD: // standard kd-splitting rule
root = rbd_tree(es_info, pa, pidx, n, dd, bs, bnd_box, kd_split, shrink);
break;
case ANN_KD_MIDPT: // midpoint split
root = rbd_tree(es_info, pa, pidx, n, dd, bs, bnd_box, midpt_split, shrink);
break;
case ANN_KD_SUGGEST: // best (in our opinion)
case ANN_KD_SL_MIDPT: // sliding midpoint split
root = rbd_tree(es_info, pa, pidx, n, dd, bs, bnd_box, sl_midpt_split, shrink);
break;
case ANN_KD_FAIR: // fair split
root = rbd_tree(es_info, pa, pidx, n, dd, bs, bnd_box, fair_split, shrink);
break;
case ANN_KD_SL_FAIR: // sliding fair split
root = rbd_tree(es_info, pa, pidx, n, dd, bs,
bnd_box, sl_fair_split, shrink);
break;
default:
annError("Illegal splitting method", ANNabort);
}
}
ANNdecomp selectDecomp( // select decomposition method
ES_INFO* es_info,
ANNpointArray pa, // point array
ANNidxArray pidx, // point indices to store in subtree
int n, // number of points
int dim, // dimension of space
const ANNorthRect &bnd_box, // current bounding box
ANNkd_splitter splitter, // splitting procedure
ANNshrinkRule shrink, // shrinking rule
ANNorthRect &inner_box) // inner box if shrinking (returned)
{
ANNdecomp decomp = SPLIT; // decomposition
switch (shrink) { // check shrinking rule
case ANN_BD_NONE: // no shrinking allowed
decomp = SPLIT;
break;
case ANN_BD_SUGGEST: // author's suggestion
case ANN_BD_SIMPLE: // simple shrink
decomp = trySimpleShrink(
es_info,
pa, pidx, // points and indices
n, dim, // number of points and dimension
bnd_box, // current bounding box
inner_box); // inner box if shrinking (returned)
break;
case ANN_BD_CENTROID: // centroid shrink
decomp = tryCentroidShrink(
es_info,
pa, pidx, // points and indices
n, dim, // number of points and dimension
bnd_box, // current bounding box
splitter, // splitting procedure
inner_box); // inner box if shrinking (returned)
break;
default:
annError("Illegal shrinking rule", ANNabort);
}
return decomp;
}
ANNkd_tree::ANNkd_tree( // construct from point array
ANNpointArray pa, // point array (with at least n pts)
int n, // number of points
int dd, // dimension
double *ss, // scaling coefficient
int *tt, // topology of space
int bs, // bucket size
ANNsplitRule split) // splitting method
{
SkeletonTree(n, dd, bs); // set up the basic stuff
pts = pa; // where the points are
if (n == 0) return; // no points--no sweat
Scale = new double [dim];
Topology = new int [dim];
TreeTopology = new int [dim];
TreeP3Topology = new int [dim];
for (int i = 0; i < dim; i++) {
Scale[i] = ss[i];
Topology[i] = tt[i];
TreeTopology[i] = tt[i];
}
for (int i = 0; i < dim; i++) {
if (tt[i] != 3) TreeP3Topology[i] = 0;
else {
TreeP3Topology[i++] = 0;
TreeP3Topology[i++] = 1;
TreeP3Topology[i++] = 2;
TreeP3Topology[i] = 3;
}
}
ANNorthRect bnd_box(dd); // bounding box for points
annEnclRect(pa, pidx, n, dd, bnd_box);// construct bounding rectangle
// copy to tree structure
bnd_box_lo = annCopyPt(dd, bnd_box.lo);
bnd_box_hi = annCopyPt(dd, bnd_box.hi);
switch (split) { // build by rule
case ANN_KD_STD: // standard kd-splitting rule
root = rkd_tree(pa, pidx, n, dd, bs, bnd_box, kd_split);
break;
case ANN_KD_MIDPT: // midpoint split
root = rkd_tree(pa, pidx, n, dd, bs, bnd_box, midpt_split);
break;
case ANN_KD_FAIR: // fair split
root = rkd_tree(pa, pidx, n, dd, bs, bnd_box, fair_split);
break;
case ANN_KD_SUGGEST: // best (in our opinion)
case ANN_KD_SL_MIDPT: // sliding midpoint split
root = rkd_tree(pa, pidx, n, dd, bs, bnd_box, sl_midpt_split);
break;
case ANN_KD_SL_FAIR: // sliding fair split
root = rkd_tree(pa, pidx, n, dd, bs, bnd_box, sl_fair_split);
break;
default:
annError("Illegal splitting method", ANNabort);
}
delete [] TreeTopology;
delete [] TreeP3Topology;
}
