Fix up 5e3d6d4f84b78975b566367c7da611b9c6260967

src/mynonlinearity.hh

@@ -29,7 +29,7 @@ class MyNonlinearity {
   void directionalSubDiff(VectorType const u, VectorType const v,
                           Interval<double> &D) const {
     if (u == SmallVector(0.0)) {
-      D[0] = D[1] = func_.rightDifferential(0);
+      D[0] = D[1] = func_.rightDifferential(0) * v.two_norm();
       return;
     }
     double const un = u.two_norm();