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Fixed a bug in partitioning function for constructing trees out of hyperrectnalges.

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This commit is contained in:
Dongryeol Lee
2008-05-02 20:38:12 +00:00
parent 27890d409d
commit 68406f6ecb
1 changed files with 28 additions and 13 deletions
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fastlib2/contrib/dongryel/proximity_project/gen_kdtree_hyper_impl.h
+28 -13
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@@ -25,6 +25,7 @@ namespace tree_gen_kdtree_private {
template<typename T, typename TBound>
index_t MatrixPartition(GenMatrix<T>& lower_limit_matrix,
GenMatrix<T>& upper_limit_matrix,
index_t split_matrix,
index_t dim, double splitvalue,
index_t first, index_t count, TBound* left_bound,
TBound* right_bound, index_t *old_from_new) {
@@ -41,8 +42,11 @@ namespace tree_gen_kdtree_private {
// If the lower limit is at most the split value, then put it in
// the left.
while (lower_limit_matrix.get(dim, left) < splitvalue &&
likely(left <= right)) {
double left_split = (split_matrix == 0) ?
lower_limit_matrix.get(dim, left):upper_limit_matrix.get(dim, left);
double right_split = (split_matrix == 0) ?
lower_limit_matrix.get(dim, right):upper_limit_matrix.get(dim, right);
while (left_split < splitvalue && likely(left <= right)) {
GenVector<T> left_vector;
lower_limit_matrix.MakeColumnVector(left, &left_vector);
*left_bound |= left_vector;
@@ -50,12 +54,13 @@ namespace tree_gen_kdtree_private {
upper_limit_matrix.MakeColumnVector(left, &left_vector);
*left_bound |= left_vector;
left++;
left_split = (split_matrix == 0) ?
lower_limit_matrix.get(dim, left):upper_limit_matrix.get(dim, left);
}
// If the upper limit is at least the split value, then put it
// in the right.
while (lower_limit_matrix.get(dim, right) >= splitvalue &&
likely(left <= right)) {
while (right_split >= splitvalue && likely(left <= right)) {
GenVector<T> right_vector;
lower_limit_matrix.MakeColumnVector(right, &right_vector);
*right_bound |= right_vector;
@@ -63,6 +68,9 @@ namespace tree_gen_kdtree_private {
upper_limit_matrix.MakeColumnVector(right, &right_vector);
*right_bound |= right_vector;
right--;
right_split = (split_matrix == 0) ?
lower_limit_matrix.get(dim, right):
upper_limit_matrix.get(dim, right);
}
if (unlikely(left > right)) {
@@ -120,12 +128,15 @@ namespace tree_gen_kdtree_private {
if (node->count() > leaf_size) {
index_t split_dim = BIG_BAD_NUMBER;
T max_width = -1;
double split_val = -1;
index_t split_matrix = -1;
for (index_t d = 0; d < lower_limit_matrix.n_rows(); d++) {
T min_coord = 1;
T max_coord = 0;
for(index_t p = node->begin(); p < node->end(); p++) {
if(p == node->begin()) {
min_coord = max_coord = lower_limit_matrix.get(d, p);
}
else {
min_coord = std::min(min_coord, lower_limit_matrix.get(d, p));
@@ -135,25 +146,29 @@ namespace tree_gen_kdtree_private {
T w = max_coord - min_coord;
for(index_t p = node->begin(); p < node->end(); p++) {
if(p == node->begin()) {
min_coord = max_coord = upper_limit_matrix.get(d, p);
}
else {
min_coord = std::min(min_coord, upper_limit_matrix.get(d, p));
max_coord = std::max(max_coord, upper_limit_matrix.get(d, p));
}
}
w = std::max(w, (T) (max_coord - min_coord));
T w2 = max_coord - min_coord;
if(w > w2) {
split_matrix = 0;
}
else {
split_matrix = 1;
}
w = std::max(w2, (T) (max_coord - min_coord));
if (unlikely(w > max_width)) {
max_width = w;
split_dim = d;
split_val = 0.5 * (max_coord + min_coord);
}
}
// choose the split value along the dimension to be splitted
double split_val =
TKdTreeSplitter::ChooseKdTreeSplitValue(lower_limit_matrix,
upper_limit_matrix, node,
split_dim);
if (max_width < DBL_EPSILON) {
// Okay, we can't do any splitting, because all these points are the
@@ -167,7 +182,7 @@ namespace tree_gen_kdtree_private {
right->bound().Init(lower_limit_matrix.n_rows());
index_t split_col =
MatrixPartition(lower_limit_matrix, upper_limit_matrix,
MatrixPartition(lower_limit_matrix, upper_limit_matrix, split_matrix,
split_dim, split_val,
node->begin(), node->count(),
&left->bound(), &right->bound(),