improved vector_vector.h performance

git-svn-id: https://phat.googlecode.com/svn/trunk@47 8e3bb3c2-eed4-f18f-5264-0b6c94e6926d

1 files changed, 7 insertions, 5 deletions

diff --git a/include/phat/representations/vector_vector.h b/include/phat/representations/vector_vector.h
index bdef522..84609c2 100644
--- a/include/phat/representations/vector_vector.h
+++ b/include/phat/representations/vector_vector.h
@@ -27,6 +27,8 @@ namespace phat {
         std::vector< dimension > dims;

         std::vector< column > matrix;

 

+        thread_local_storage< column > temp_column_buffer;

+

     public:

         // overall number of cells in boundary_matrix

         index _get_num_cols() const {

@@ -80,12 +82,12 @@ namespace phat {
         void _add_to( index source, index target ) {

             column& source_col = matrix[ source ];

             column& target_col = matrix[ target ];

-            column temp_col;

-            target_col.swap( temp_col );

-            target_col.reserve( temp_col.size() );

-            std::set_symmetric_difference( temp_col.begin(), temp_col.end(),

+            column& temp_col = temp_column_buffer();

+            temp_col.clear();

+            std::set_symmetric_difference( target_col.begin(), target_col.end(),

                                            source_col.begin(), source_col.end(),

-                                           std::back_inserter( target_col ) );

+                                           std::back_inserter( temp_col ) );

+            target_col.swap( temp_col );

         }

     };

 }