[PPL-devel] [GIT] ppl/ppl(sparse_matrices): PIP_Solution_Node: swap elements instead of copy-constructing them, in update_tableau().

[Marco Poletti]

Module: ppl/ppl
Branch: sparse_matrices
Commit: 76c398b3ee72ab472c15d19bd5db2ee3b7887a2d
URL:    http://www.cs.unipr.it/git/gitweb.cgi?p=ppl/ppl.git;a=commit;h=76c398b3ee72ab472c15d19bd5db2ee3b7887a2d

Author: Marco Poletti <poletti.marco at gmail.com>
Date:   Thu Mar 25 18:54:39 2010 +0100

PIP_Solution_Node: swap elements instead of copy-constructing them, in update_tableau().

---

 src/PIP_Tree.cc |   45 ++++++++++++++++++++++++++++++---------------
 1 files changed, 30 insertions(+), 15 deletions(-)

diff --git a/src/PIP_Tree.cc b/src/PIP_Tree.cc
index 9f95009..97033ca 100644
--- a/src/PIP_Tree.cc
+++ b/src/PIP_Tree.cc
@@ -2255,14 +2255,19 @@ PIP_Solution_Node::update_tableau(const PIP_Problem& pip,
             {
               std::sort(buffer.begin(), buffer.end());
               std::vector<std::pair<dimension_type,Coefficient> >
-                ::const_iterator j = buffer.begin();
+                ::iterator j = buffer.begin();
               std::vector<std::pair<dimension_type,Coefficient> >
-                ::const_iterator j_end = buffer.end();
+                ::iterator j_end = buffer.end();
               if (j != j_end) {
-                matrix_row_iterator itr = v_row.find_create(*j);
+                matrix_row_iterator itr = v_row.find_create(j->first);
+                // We need to do (*itr).second = j->second, this is faster.
+                std::swap((*itr).second, j->second);
                 ++j;
-                for ( ; j != j_end; ++j)
-                  itr = v_row.find_create(*j, itr);
+                for ( ; j != j_end; ++j) {
+                  itr = v_row.find_create(j->first, itr);
+                  // We need to do (*itr).second = j->second, this is faster.
+                  std::swap((*itr).second, j->second);
+                }
               }
             }
             buffer.clear();
@@ -2302,14 +2307,19 @@ PIP_Solution_Node::update_tableau(const PIP_Problem& pip,
             {
               std::sort(buffer.begin(), buffer.end());
               std::vector<std::pair<dimension_type,Coefficient> >
-                ::const_iterator j = buffer.begin();
+                ::iterator j = buffer.begin();
               std::vector<std::pair<dimension_type,Coefficient> >
-                ::const_iterator j_end = buffer.end();
+                ::iterator j_end = buffer.end();
               if (j != j_end) {
-                matrix_row_iterator itr = v_row.find_create(*j);
+                matrix_row_iterator itr = v_row.find_create(j->first);
+                // We need to do (*itr).second = j->second, this is faster.
+                std::swap((*itr).second, j->second);
                 ++j;
-                for ( ; j != j_end; ++j)
-                  itr = v_row.find_create(*j, itr);
+                for ( ; j != j_end; ++j) {
+                  itr = v_row.find_create(j->first, itr);
+                  // We need to do (*itr).second = j->second, this is faster.
+                  std::swap((*itr).second, j->second);
+                }
               }
             }
             buffer.clear();
@@ -2324,14 +2334,19 @@ PIP_Solution_Node::update_tableau(const PIP_Problem& pip,
       {
         std::sort(buffer.begin(), buffer.end());
         std::vector<std::pair<dimension_type,Coefficient> >
-          ::const_iterator j = buffer.begin();
+          ::iterator j = buffer.begin();
         std::vector<std::pair<dimension_type,Coefficient> >
-          ::const_iterator j_end = buffer.end();
+          ::iterator j_end = buffer.end();
         if (j != j_end) {
-          matrix_row_iterator itr = v_row.find_create(*j);
+          matrix_row_iterator itr = v_row.find_create(j->first);
+          // We need to do (*itr).second = j->second, this is faster.
+          std::swap((*itr).second, j->second);
           ++j;
-          for ( ; j != j_end; ++j)
-            itr = v_row.find_create(*j, itr);
+          for ( ; j != j_end; ++j) {
+            itr = v_row.find_create(j->first, itr);
+            // We need to do (*itr).second = j->second, this is faster.
+            std::swap((*itr).second, j->second);
+          }
         }
       }
       buffer.clear();