Multiple code fixes: avoid C++17, fix compilation, remove whitespace

diff --git a/examples/step-69/doc/intro.dox b/examples/step-69/doc/intro.dox
index 9d52a6bbe3ff44cb726644f339231e5dbea372db..3f6f97ff59fa3bea50ea385bbed4ab1e45ba5637 100644 (file)
--- a/examples/step-69/doc/intro.dox
+++ b/examples/step-69/doc/intro.dox
@@ -135,7 +135,7 @@ Here, $s(\mathbf{u})$ denotes the specific entropy
 @f{align}
   s(\mathbf{u}) = \ln \Big(\frac{p(\mathbf{u})}{\rho^{\gamma}}\Big).
 @f}
-We will refer to $\mathcal{B}$ as the invariant set of Euler's equations. 
+We will refer to $\mathcal{B}$ as the invariant set of Euler's equations.
 In other words, a state $\mathbf{u}(\mathbf{x},t)\in\mathcal{B}$ obeys
 positivity of the density, positivity of the internal energy, and a local
 minimum principle on the specific entropy. This condition is a simplified
@@ -357,7 +357,7 @@ cells but rather over all edges of the sparsity graph.
 no bilinear forms, no cell loops, and no quadrature) outside of the finite
 element community in the wider CFD community. There is a rich history of
 application of this kind of schemes, also called <i>edge-based</i> or
-<i>graph-based</i> finite element schemes (see for instance 
+<i>graph-based</i> finite element schemes (see for instance
 @cite Rainald2008 for a historical overview).
 
 @todo Explain what to do for slip, dirichlet and do-nothing boundary

diff --git a/examples/step-69/doc/results.dox b/examples/step-69/doc/results.dox
index f7b6b04a2eb3c9ff696d8a8af3710828c7d110a6..9b07843d817fbc443cc99d5f57c528030565ebbc 100644 (file)
--- a/examples/step-69/doc/results.dox
+++ b/examples/step-69/doc/results.dox
@@ -4,7 +4,7 @@
 Running the program with default parameters in release mode takes about 1
 minute on a 4 core machine (with hyperthreading):
 @verbatim
-$ mpirun -np 4 ./step-69 | tee output
+# mpirun -np 4 ./step-69 | tee output
 Reading parameters and allocating objects... done
 
     ####################################################
@@ -107,7 +107,7 @@ So, we give the first-order method a second chance and run it with about
 2.4M gridpoints on a small compute server:
 
 @verbatim
-$ mpirun -np 16 ./step-69 | tee output
+# mpirun -np 16 ./step-69 | tee output
 
 [...]
 

diff --git a/examples/step-69/step-69.cc b/examples/step-69/step-69.cc
index bab07f39a47480d47b6a2a4e7e22bf864a6812c1..a79d696e46ed29e984e9f7870ad5ced4481b5a3e 100644 (file)
--- a/examples/step-69/step-69.cc
+++ b/examples/step-69/step-69.cc
@@ -1362,8 +1362,8 @@ namespace Step69
                                                                             f))
                       continue;
 
-                    const auto &[normal_j, _1, _2] =
-                      boundary_normal_map[local_dof_indices[j]];
+                    const auto &normal_j =
+                      std::get<0>(boundary_normal_map[local_dof_indices[j]]);
 
                     const auto value_JxW =
                       fe_face_values.shape_value(j, q) * JxW;
@@ -1650,7 +1650,7 @@ namespace Step69
       /* Formula (2.11) in Guermond-Popov-2016 */
 
       return std::max(positive_part(lambda3), negative_part(lambda1));
-    };
+    }
 
     // We compute a second upper bound of the maximal wavespeed that is in
     // general, not as sharp as the two-rarefaction estimate. But it will