And bug fix of a bug introduced today :)

AMDiS/src/ProblemStat.cc

@@ -1549,8 +1549,11 @@ namespace AMDiS {
     BoundaryType *bound = 
       useGetBound ? new BoundaryType[basisFcts->getNumber()] : NULL;
 
-    matrix->startInsertion(matrix->getNnz());
-    vector->set(0.0);
+    if (matrix)
+      matrix->startInsertion(matrix->getNnz());
+    
+    if (vector)
+      vector->set(0.0);
 
     // == Traverse mesh and assemble. ==
     ElInfo *elInfo = stack.traverseFirst(mesh, -1, assembleFlag);