Comment correction in step-15

diff --git a/examples/step-15/step-15.cc b/examples/step-15/step-15.cc
index 669983884972a72d0f0449a57fd5c591e7123600..469ff2c32176835d5fda40184acc7066e4d8a9b9 100644 (file)
--- a/examples/step-15/step-15.cc
+++ b/examples/step-15/step-15.cc
@@ -288,7 +288,7 @@ namespace Step15
 
                 cell_rhs(i) -= (fe_values.shape_grad(i, q)  // \nabla \phi_i
                                 * coeff                     // * a_n
-                                * old_solution_gradients[q] // * u_n
+                                * old_solution_gradients[q] // * \nabla u_n
                                 * fe_values.JxW(q));        // * dx
               }
           }
@@ -534,7 +534,7 @@ namespace Step15
             for (unsigned int i = 0; i < dofs_per_cell; ++i)
               cell_residual(i) -= (fe_values.shape_grad(i, q) // \nabla \phi_i
                                    * coeff                    // * a_n
-                                   * gradients[q]             // * u_n
+                                   * gradients[q]             // * \nabla u_n
                                    * fe_values.JxW(q));       // * dx
           }