From b6cc3503531def340038febf90f0e191bad4af3b Mon Sep 17 00:00:00 2001
From: Wolfgang Bangerth <bangerth@colostate.edu>
Date: Wed, 5 May 2021 09:58:46 -0600
Subject: [PATCH] Add a test.

---
 tests/fe/nedelec_projection_01.cc     | 155 ++++++++++++++++++++++++++
 tests/fe/nedelec_projection_01.output |  29 +++++
 2 files changed, 184 insertions(+)
 create mode 100644 tests/fe/nedelec_projection_01.cc
 create mode 100644 tests/fe/nedelec_projection_01.output

diff --git a/tests/fe/nedelec_projection_01.cc b/tests/fe/nedelec_projection_01.cc
new file mode 100644
index 0000000000..802d3525e0
--- /dev/null
+++ b/tests/fe/nedelec_projection_01.cc
@@ -0,0 +1,155 @@
+// ---------------------------------------------------------------------
+//
+// Copyright (C) 2021 by the deal.II authors
+//
+// This file is part of the deal.II library.
+//
+// The deal.II library is free software; you can use it, redistribute
+// it, and/or modify it under the terms of the GNU Lesser General
+// Public License as published by the Free Software Foundation; either
+// version 2.1 of the License, or (at your option) any later version.
+// The full text of the license can be found in the file LICENSE.md at
+// the top level directory of deal.II.
+//
+// ---------------------------------------------------------------------
+
+
+// Check that VectorTools::project_boundary_values_curl_conforming_l2
+// also works on systems of Nedelec elements. This is a variation of a
+// testcase by Abbas Ballout posted to the mailing list.
+
+#include <deal.II/base/function.h>
+
+#include <deal.II/dofs/dof_handler.h>
+#include <deal.II/dofs/dof_renumbering.h>
+
+#include <deal.II/fe/fe_nedelec.h>
+#include <deal.II/fe/fe_system.h>
+#include <deal.II/fe/mapping_q.h>
+
+#include <deal.II/grid/grid_generator.h>
+#include <deal.II/grid/tria.h>
+
+#include <deal.II/lac/affine_constraints.h>
+
+#include <deal.II/numerics/vector_tools.h>
+
+#include "../tests.h"
+
+
+
+template <int dim>
+class BoundaryValues : public Function<dim>
+{
+public:
+  BoundaryValues()
+    : Function<dim>(2 * dim)
+  {}
+
+  void
+  vector_value_list(const std::vector<Point<dim>> &points,
+                    std::vector<Vector<double>> &  values) const override
+  {
+    for (unsigned int i = 0; i < points.size(); ++i)
+      {
+        values[i][0] = 1.0;
+        values[i][1] = 0.0;
+        if (dim == 3)
+          values[i][2] = 0.0;
+        values[i][dim + 0] = 1.0;
+        values[i][dim + 1] = 0.0;
+        if (dim == 3)
+          values[i][dim + 2] = 0.0;
+      }
+  }
+};
+
+
+
+template <int dim>
+void
+test()
+{
+  deallog << "*** dim=" << dim << std::endl;
+
+  Triangulation<dim> triangulation;
+
+  GridGenerator::hyper_cube(triangulation);
+  triangulation.begin_active()
+    ->face(dim == 2 ? 2 : 4)
+    ->set_boundary_id(1); // set the 4th boundary id to 1 to apply dirichlet BC
+
+  DoFHandler<dim> dof_handler(triangulation);
+  FESystem<dim>   fe(FE_Nedelec<dim>(0), 2);
+  dof_handler.distribute_dofs(fe);
+  DoFRenumbering::component_wise(dof_handler);
+
+  // First try to apply constraints only to the first 3 components
+  {
+    deallog << "Check 1:" << std::endl;
+
+    AffineConstraints<double> constraints;
+
+    VectorTools::project_boundary_values_curl_conforming_l2(
+      dof_handler,
+      0, // starting compenent
+      BoundaryValues<dim>(),
+      1, // face ID1
+      constraints,
+      StaticMappingQ1<dim>::mapping);
+    constraints.close();
+    constraints.print(deallog.get_file_stream());
+  }
+
+  // Try again with just the second 3 components
+  {
+    deallog << "Check 2:" << std::endl;
+
+    AffineConstraints<double> constraints;
+
+    VectorTools::project_boundary_values_curl_conforming_l2(
+      dof_handler,
+      dim, // starting component
+      BoundaryValues<dim>(),
+      1, // face ID1
+      constraints,
+      StaticMappingQ1<dim>::mapping);
+    constraints.close();
+    constraints.print(deallog.get_file_stream());
+  }
+
+  // And now with all
+  {
+    deallog << "Check 3:" << std::endl;
+
+    AffineConstraints<double> constraints;
+
+    VectorTools::project_boundary_values_curl_conforming_l2(
+      dof_handler,
+      0, // starting compenent
+      BoundaryValues<dim>(),
+      1, // face ID1
+      constraints,
+      StaticMappingQ1<dim>::mapping);
+    VectorTools::project_boundary_values_curl_conforming_l2(
+      dof_handler,
+      dim, // starting compenent
+      BoundaryValues<dim>(),
+      1, // face ID1
+      constraints,
+      StaticMappingQ1<dim>::mapping);
+    constraints.close();
+    constraints.print(deallog.get_file_stream());
+  }
+}
+
+
+
+int
+main()
+{
+  initlog();
+
+  test<2>();
+  test<3>();
+}
diff --git a/tests/fe/nedelec_projection_01.output b/tests/fe/nedelec_projection_01.output
new file mode 100644
index 0000000000..39c9bdadfe
--- /dev/null
+++ b/tests/fe/nedelec_projection_01.output
@@ -0,0 +1,29 @@
+
+DEAL::*** dim=2
+DEAL::Check 1:
+    2 = 1.00000
+DEAL::Check 2:
+    6 = 1.00000
+DEAL::Check 3:
+    2 = 1.00000
+    6 = 1.00000
+DEAL::*** dim=3
+DEAL::Check 1:
+    0 = 0
+    1 = 0
+    2 = 1.00000
+    3 = 1.00000
+DEAL::Check 2:
+    12 = 0
+    13 = 0
+    14 = 1.00000
+    15 = 1.00000
+DEAL::Check 3:
+    0 = 0
+    1 = 0
+    2 = 1.00000
+    3 = 1.00000
+    12 = 0
+    13 = 0
+    14 = 1.00000
+    15 = 1.00000
-- 
2.39.5