[mlpack-git] master: Optimization: don't needlessly tighten point bounds. (a5b9c34)

[gitdub at big.cc.gt.atl.ga.us]

Repository : https://github.com/mlpack/mlpack

On branch  : master
Link       : https://github.com/mlpack/mlpack/compare/5249c0fc83ac3b0915bd22ae1f1823b742a82c33...803224f64f6b6490c3cb8aafd528b1db069ef2f1

>---------------------------------------------------------------

commit a5b9c34ea77c788e1b313065f1ac1226cacbd4fb
Author: Ryan Curtin <ryan at ratml.org>
Date:   Thu May 28 15:21:29 2015 -0400

    Optimization: don't needlessly tighten point bounds.


>---------------------------------------------------------------

a5b9c34ea77c788e1b313065f1ac1226cacbd4fb
 src/mlpack/methods/kmeans/dual_tree_kmeans_impl.hpp | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/src/mlpack/methods/kmeans/dual_tree_kmeans_impl.hpp b/src/mlpack/methods/kmeans/dual_tree_kmeans_impl.hpp
index c584843..135dece 100644
--- a/src/mlpack/methods/kmeans/dual_tree_kmeans_impl.hpp
+++ b/src/mlpack/methods/kmeans/dual_tree_kmeans_impl.hpp
@@ -287,7 +287,6 @@ visited[node.Descendant(i)] << ".\n";
   }
 */
 
-
   if ((node.Stat().Pruned() == centroids.n_cols) &&
       (node.Stat().Owner() < centroids.n_cols))
   {
@@ -334,7 +333,17 @@ visited[node.Descendant(i)] << ".\n";
   }
 
   bool allPointsPruned = true;
-  if (!node.Stat().StaticPruned())
+  if (tree::TreeTraits<TreeType>::HasSelfChildren && node.NumChildren() > 0)
+  {
+    // If this tree type has self-children, then we have already adjusted the
+    // point bounds at a lower level, and we can determine if all of our points
+    // are pruned simply by seeing if all of the children's points are pruned.
+    // This particular line below additionally assumes that each node's points
+    // are all contained in its first child.  This is valid for the cover tree,
+    // but maybe not others.
+    allPointsPruned = node.Child(0).Stat().StaticPruned();
+  }
+  else if (!node.Stat().StaticPruned())
   {
     // Try to prune individual points.
     for (size_t i = 0; i < node.NumPoints(); ++i)