Bugfix: index 'j' should be 'k'

dune/solvers/iterationsteps/projectedblockgsstep.cc

@@ -68,7 +68,7 @@ void ProjectedBlockGSStep<OperatorType, DiscFuncType>::iterate()
                     v[k] += sr / mat[i][i][k][k];
 
                     // Project
-                    if (hasObstacle_[i][j]==true) {
+                    if (hasObstacle_[i][k]==true) {
                         if (v[k] < defectObstacle.lower(k))
                             v[k] = defectObstacle.lower(k);
                         else if (v[k] > defectObstacle.upper(k))