Matrix loadbalance to more

There was a problem when having the global matrix and using load balance to distribute it. This is fixed by the MR.

These changes should be cherrypicked to the release, too. If that is still possible.

dune/istl/repartition.hh

@@ -404,26 +404,17 @@ namespace Dune
       int i=0;
       int j=0;
 
-      std::vector<int> domain(nparts);
-      std::vector<int> assigned(npes);
-      // init
-      for (i=0; i<nparts; i++) {
-        domainMapping[i] = -1;
-        domain[i] = 0;
-      }
-      for (i=0; i<npes; i++) {
-        assigned[i] = -0;
-      }
+      std::vector<int> domain(nparts, 0);
+      std::vector<int> assigned(npes, 0);
+      // init domain Mapping
+      domainMapping.assign(domainMapping.size(), -1);
+
       // count the occurance of domains
       for (i=0; i<numOfOwnVtx; i++) {
         domain[part[i]]++;
       }
 
-      int *domainMatrix = new int[npes * nparts];
-      // init
-      for(i=0; i<npes*nparts; i++) {
-        domainMatrix[i]=-1;
-      }
+      std::vector<int> domainMatrix(npes * nparts, -1);
 
       // init buffer with the own domain
       int *buf = new int[nparts];
@@ -451,6 +442,8 @@ namespace Dune
       // particular domain is selected to choose it's favorate domain
       int maxOccurance = 0;
       pe = -1;
+      std::set<std::size_t> unassigned;
+
       for(i=0; i<nparts; i++) {
         for(j=0; j<npes; j++) {
           // process has no domain assigned
@@ -472,11 +465,23 @@ namespace Dune
           }
           pe = -1;
         }
+        else
+        {
+          unassigned.insert(i);
+        }
         maxOccurance = 0;
       }
 
-      delete[] domainMatrix;
+      typename std::vector<int>::iterator next_free = assigned.begin();
 
+      for(typename std::set<std::size_t>::iterator domain = unassigned.begin(),
+            end = unassigned.end(); domain != end; ++domain)
+      {
+        next_free = std::find_if(next_free, assigned.end(), std::bind2nd(std::less<int>(), 1));
+        assert(next_free !=  assigned.end());
+        domainMapping[*domain] = next_free-assigned.begin();
+        *next_free = 1;
+      }
     }
 
     struct SortFirst