[mlpack-git] master, mlpack-1.0.x: Fix #334 by ensuring vector accesses don't go out of bounds. (bd7aef7)

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

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

On branches: master,mlpack-1.0.x
Link       : https://github.com/mlpack/mlpack/compare/904762495c039e345beba14c1142fd719b3bd50e...f94823c800ad6f7266995c700b1b630d5ffdcf40

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

commit bd7aef7910acf070c83acfea3da4568d3e7388b3
Author: Ryan Curtin <ryan at ratml.org>
Date:   Thu Jun 12 20:57:22 2014 +0000

    Fix #334 by ensuring vector accesses don't go out of bounds.


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

bd7aef7910acf070c83acfea3da4568d3e7388b3
 src/mlpack/methods/det/dt_utils.cpp | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/src/mlpack/methods/det/dt_utils.cpp b/src/mlpack/methods/det/dt_utils.cpp
index 2db68e0..273ed98 100644
--- a/src/mlpack/methods/det/dt_utils.cpp
+++ b/src/mlpack/methods/det/dt_utils.cpp
@@ -214,8 +214,10 @@ DTree* mlpack::det::Trainer(arma::mat& dataset,
         minLeafSize);
 
     // Sequentially prune with all the values of available alphas and adding
-    // values for test values.
-    for (size_t i = 0; i < prunedSequence.size() - 2; ++i)
+    // values for test values.  Don't enter this loop if there are less than two
+    // trees in the pruned sequence.
+    for (size_t i = 0;
+         i < ((prunedSequence.size() < 2) ? 0 : prunedSequence.size() - 2); ++i)
     {
       // Compute test values for this state of the tree.
       double cvVal = 0.0;
@@ -242,8 +244,9 @@ DTree* mlpack::det::Trainer(arma::mat& dataset,
       cvVal += cvDTree->ComputeValue(testPoint);
     }
 
-    regularizationConstants[prunedSequence.size() - 2] += 2.0 * cvVal /
-        (double) dataset.n_cols;
+    if (prunedSequence.size() > 2)
+      regularizationConstants[prunedSequence.size() - 2] += 2.0 * cvVal /
+          (double) dataset.n_cols;
 
     test.reset();
     delete cvDTree;