From: kronbichler <kronbichler@0785d39b-7218-0410-832d-ea1e28bc413d>
Date: Thu, 5 Mar 2009 16:00:57 +0000 (+0000)
Subject: I introduced an error in the copy_from function that appeared only when running with... 
X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=7ae615e2b2f6de644e5c8e7e39c9e946297c6b79;p=dealii-svn.git

I introduced an error in the copy_from function that appeared only when running with MPI. This is now fixed again.

git-svn-id: https://svn.dealii.org/trunk@18456 0785d39b-7218-0410-832d-ea1e28bc413d
---

diff --git a/deal.II/lac/source/trilinos_sparse_matrix.cc b/deal.II/lac/source/trilinos_sparse_matrix.cc
index 3773d939a2..9ef30e4069 100755
--- a/deal.II/lac/source/trilinos_sparse_matrix.cc
+++ b/deal.II/lac/source/trilinos_sparse_matrix.cc
@@ -253,8 +253,16 @@ namespace TrilinosWrappers
   {
     row_map = m.row_map;
     col_map = m.col_map;
-    matrix = std::auto_ptr<Epetra_FECrsMatrix>
-      (new Epetra_FECrsMatrix(*m.matrix));
+				   // check whether we need to update the
+				   // communicator or can just copy the
+				   // data: in case we have the same
+				   // distribution, we can just copy the
+				   // data.
+    if (local_range() == m.local_range())
+      *matrix = *m.matrix;
+    else
+      matrix = std::auto_ptr<Epetra_FECrsMatrix>
+	(new Epetra_FECrsMatrix(*m.matrix));
     compress();
     return *this;
   }