From 1ada58cbc1e70c58cfab539cc3746f40abac9a2a Mon Sep 17 00:00:00 2001
From: Matthias Maier <tamiko@43-1.org>
Date: Mon, 25 Jun 2018 17:47:58 -0500
Subject: [PATCH] update

---
 examples/step-4/step-4.cc | 32 ++++++++++++++------------------
 1 file changed, 14 insertions(+), 18 deletions(-)

diff --git a/examples/step-4/step-4.cc b/examples/step-4/step-4.cc
index 021be4f293..a63c86d40e 100644
--- a/examples/step-4/step-4.cc
+++ b/examples/step-4/step-4.cc
@@ -257,11 +257,9 @@ void Step4<dim>::make_grid()
   GridGenerator::hyper_cube(triangulation, -1, 1);
   triangulation.refine_global(4);
 
-  std::cout << "   Number of active cells: "  //
-            << triangulation.n_active_cells() //
-            << std::endl                      //
-            << "   Total number of cells: "   //
-            << triangulation.n_cells()        //
+  std::cout << "   Number of active cells: " << triangulation.n_active_cells()
+            << std::endl
+            << "   Total number of cells: " << triangulation.n_cells()
             << std::endl;
 }
 
@@ -277,8 +275,7 @@ void Step4<dim>::setup_system()
 {
   dof_handler.distribute_dofs(fe);
 
-  std::cout << "   Number of degrees of freedom: " //
-            << dof_handler.n_dofs()                //
+  std::cout << "   Number of degrees of freedom: " << dof_handler.n_dofs()
             << std::endl;
 
   DynamicSparsityPattern dsp(dof_handler.n_dofs());
@@ -369,14 +366,15 @@ void Step4<dim>::assemble_system()
         for (unsigned int i = 0; i < dofs_per_cell; ++i)
           {
             for (unsigned int j = 0; j < dofs_per_cell; ++j)
-              cell_matrix(i, j) += (fe_values.shape_grad(i, q_index) * //
-                                    fe_values.shape_grad(j, q_index) * //
-                                    fe_values.JxW(q_index));
-
-            cell_rhs(i) +=
-              (fe_values.shape_value(i, q_index) *
-               right_hand_side.value(fe_values.quadrature_point(q_index)) *
-               fe_values.JxW(q_index));
+              cell_matrix(i, j) +=
+                (fe_values.shape_grad(i, q_index) * // grad phi_i(x_q)
+                 fe_values.shape_grad(j, q_index) * // grad phi_j(x_q)
+                 fe_values.JxW(q_index));           // dx
+
+            const auto x_q = fe_values.quadrature_point(q_index);
+            cell_rhs(i) += (fe_values.shape_value(i, q_index) * // phi_i(x_q)
+                            right_hand_side.value(x_q) *        // f(x_q)
+                            fe_values.JxW(q_index));            // dx
           }
       // As a final remark to these loops: when we assemble the local
       // contributions into <code>cell_matrix(i,j)</code>, we have to multiply
@@ -491,9 +489,7 @@ void Step4<dim>::output_results() const
 template <int dim>
 void Step4<dim>::run()
 {
-  std::cout << "Solving problem in " //
-            << dim                   //
-            << " space dimensions."  //
+  std::cout << "Solving problem in " << dim << " space dimensions."
             << std::endl;
 
   make_grid();
-- 
2.39.5