From a09c3e3314a00002c5e4e49ea2811cb1006d728e Mon Sep 17 00:00:00 2001
From: Ryan Curtin <ryan@ratml.org>
Date: Mon, 2 Feb 2015 17:23:56 -0500
Subject: [PATCH] Also use between-cluster-distance prune for points.

---
 src/mlpack/methods/kmeans/dtnn_kmeans_impl.hpp | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/src/mlpack/methods/kmeans/dtnn_kmeans_impl.hpp b/src/mlpack/methods/kmeans/dtnn_kmeans_impl.hpp
index deb98d1964..d9d56f36ea 100644
--- a/src/mlpack/methods/kmeans/dtnn_kmeans_impl.hpp
+++ b/src/mlpack/methods/kmeans/dtnn_kmeans_impl.hpp
@@ -508,6 +508,16 @@ prunedPoints[index] << ", lastOwner " << lastOwners[index] << ": invalid "
         prunedCentroids.col(owner) += dataset.col(index);
         prunedCounts(owner)++;
       }
+      else if (upperBounds[index] + clusterDistances[owner] < 0.5 *
+               interclusterDistances[newFromOldCentroids[owner]])
+      {
+        prunedPoints[index] = true;
+        upperBounds[index] += clusterDistances[owner];
+        lastOwners[index] = owner;
+        lowerSecondBounds[index] -= clusterDistances[centroids.n_cols];
+        prunedCentroids.col(owner) += dataset.col(index);
+        prunedCounts(owner)++;
+      }
       else
       {
         prunedPoints[index] = false;