Added one test exit.

AMDiS/src/MatrixVector.h

@@ -166,7 +166,7 @@ namespace AMDiS {
     /// Access to the i-th vector element.
     inline T& operator[](int i) 
     {
-      TEST_EXIT_DBG(i < size && i >= 0)("invalid index\n");
+      TEST_EXIT_DBG(i < size && i >= 0)("Invalid index %d!\n", i);
       return valArray[i];
     }