Some minor changes in AMG preconditioner to make it more stable in parallel.

git-svn-id: https://svn.dealii.org/trunk@18152 0785d39b-7218-0410-832d-ea1e28bc413d

diff --git a/deal.II/lac/source/trilinos_precondition.cc b/deal.II/lac/source/trilinos_precondition.cc
index 5df4665db086752a622b8aaff2fda6fad0177878..0ca4a33cbe37cc6e61ab11e87339ebe3c8162a6d 100755 (executable)
--- a/deal.II/lac/source/trilinos_precondition.cc
+++ b/deal.II/lac/source/trilinos_precondition.cc
@@ -567,6 +567,8 @@ namespace TrilinosWrappers
       {
        ML_Epetra::SetDefaults("SA",parameter_list);
        parameter_list.set("smoother: type", "Chebyshev");
+       if (additional_data.higher_order_elements)
+         parameter_list.set("aggregation: type", "MIS-Uncoupled");
       }
     else
       {
@@ -585,14 +587,11 @@ namespace TrilinosWrappers
     if (additional_data.output_details)
       parameter_list.set("ML output", 10);
     else
-      parameter_list.set("ML output", 0);
-  
-    if (additional_data.higher_order_elements)
-      parameter_list.set("aggregation: type", "MIS");
+      parameter_list.set("ML output", 0);  
 
-    const Epetra_Map * domain_map = &(matrix.matrix->DomainMap());
+    const Epetra_Map & domain_map = matrix.matrix->DomainMap();
     
-    Epetra_MultiVector distributed_constant_modes (*domain_map, 
+    Epetra_MultiVector distributed_constant_modes (domain_map, 
                                                   constant_modes_dimension);
   
     if (constant_modes_dimension > 1)
@@ -604,9 +603,9 @@ namespace TrilinosWrappers
                ExcDimensionMismatch(n_rows,
                                     distributed_constant_modes.GlobalLength()));
 
-       const unsigned int my_size = domain_map->NumMyElements();
-       Assert (my_size == (unsigned int)domain_map->MaxLID()+1,
-               ExcDimensionMismatch (my_size, domain_map->MaxLID()+1));
+       const unsigned int my_size = domain_map.NumMyElements();
+       Assert (my_size == (unsigned int)domain_map.MaxLID()+1,
+               ExcDimensionMismatch (my_size, domain_map.MaxLID()+1));
        
                                        // Reshape null space as a
                                        // contiguous vector of
@@ -615,7 +614,7 @@ namespace TrilinosWrappers
        for (unsigned int d=0; d<constant_modes_dimension; ++d)
          for (unsigned int row=0; row<my_size; ++row)
            {
-             int global_row_id = domain_map->GID(row);
+             int global_row_id = domain_map.GID(row);
              distributed_constant_modes.ReplaceMyValue(row, d, 
                       (double)additional_data.constant_modes[d][global_row_id]);
            }