From c4004c3036101514aa006d7042a848e2da728943 Mon Sep 17 00:00:00 2001
From: Fabian Castelli <fabian.castelli@kit.edu>
Date: Fri, 8 Oct 2021 10:48:22 +0200
Subject: [PATCH] Correction of comments in step-72

---
 examples/step-72/step-72.cc | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/examples/step-72/step-72.cc b/examples/step-72/step-72.cc
index b4b2103325..8b140bf030 100644
--- a/examples/step-72/step-72.cc
+++ b/examples/step-72/step-72.cc
@@ -367,7 +367,7 @@ namespace Step72
 
               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
             }
         }
@@ -587,7 +587,7 @@ namespace Step72
             {
               residual_ad[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
             }
         }
@@ -949,7 +949,7 @@ namespace Step72
             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
           }
 
-- 
2.39.5