Test extract constant modes 04

tests/mpi/extract_constant_modes_04.cc

@@ -0,0 +1,129 @@
+// ---------------------------------------------------------------------
+//
+// Copyright (C) 2009 - 2018 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.
+//
+// ---------------------------------------------------------------------
+
+
+
+// test DoFTools::extract_constant_modes for multi-physical problems like in
+// step-46
+
+#include <deal.II/dofs/dof_accessor.h>
+#include <deal.II/dofs/dof_handler.h>
+#include <deal.II/dofs/dof_renumbering.h>
+#include <deal.II/dofs/dof_tools.h>
+
+#include <deal.II/fe/fe_nothing.h>
+#include <deal.II/fe/fe_q.h>
+#include <deal.II/fe/fe_system.h>
+
+#include <deal.II/grid/grid_generator.h>
+#include <deal.II/grid/tria.h>
+#include <deal.II/grid/tria_accessor.h>
+#include <deal.II/grid/tria_iterator.h>
+
+#include <deal.II/hp/fe_collection.h>
+
+#include "../tests.h"
+
+
+
+template <int dim>
+void
+test(const unsigned int fe_degree)
+{
+  Triangulation<dim> triangulation;
+
+  GridGenerator::hyper_cube(triangulation, 0, 1);
+  triangulation.refine_global(1);
+
+  DoFHandler<dim> dof_handler(triangulation);
+
+  for (const auto &cell : dof_handler.active_cell_iterators())
+    {
+      if (cell->center()[0] < 0.5)
+        {
+          cell->set_active_fe_index(0);
+        }
+      else if (cell->center()[0] > 0.5)
+        {
+          cell->set_active_fe_index(1);
+        }
+      else
+        {
+          Assert(false, ExcNotImplemented());
+        }
+    }
+
+  FESystem<dim>         left_fe(FE_Q<dim>(fe_degree), 1, FE_Nothing<dim>(), 1);
+  FESystem<dim>         right_fe(FE_Nothing<dim>(), 1, FE_Q<dim>(fe_degree), 1);
+  hp::FECollection<dim> fe_collection;
+  fe_collection.push_back(left_fe);
+  fe_collection.push_back(right_fe);
+
+  dof_handler.distribute_dofs(fe_collection);
+  DoFRenumbering::component_wise(dof_handler);
+  deallog << "FE degree=" << fe_degree << std::endl;
+  deallog << "Total dofs=" << dof_handler.n_dofs() << std::endl;
+
+
+  // Define set of constant modes
+  std::vector<std::vector<bool>> constant_modes(
+    fe_collection.n_components(),
+    std::vector<bool>(dof_handler.n_locally_owned_dofs(), false));
+
+
+  // extract constant modes automatically
+  DoFTools::extract_constant_modes(dof_handler,
+                                   ComponentMask(),
+                                   constant_modes);
+
+
+  // Print constant modes
+  for (unsigned int i = 0; i < constant_modes.size(); ++i)
+    {
+      for (unsigned int j = 0; j < constant_modes[i].size(); ++j)
+        {
+          deallog << (constant_modes[i][j] ? '1' : '0') << ' ';
+        }
+      deallog << std::endl;
+    }
+}
+
+
+int
+main()
+{
+  initlog();
+
+  deallog.push("1d");
+  test<1>(1);
+  test<1>(2);
+  test<1>(3);
+  test<1>(4);
+  deallog.pop();
+
+  deallog.push("2d");
+  test<2>(1);
+  test<2>(2);
+  test<2>(3);
+  test<2>(4);
+  deallog.pop();
+
+  deallog.push("3d");
+  test<3>(1);
+  test<3>(2);
+  test<3>(3);
+  test<3>(4);
+  deallog.pop();
+}

tests/mpi/extract_constant_modes_04.output

@@ -0,0 +1,49 @@
+
+DEAL:1d::FE degree=1
+DEAL:1d::Total dofs=4
+DEAL:1d::1 1 0 0 
+DEAL:1d::0 0 1 1 
+DEAL:1d::FE degree=2
+DEAL:1d::Total dofs=6
+DEAL:1d::1 1 1 0 0 0 
+DEAL:1d::0 0 0 1 1 1 
+DEAL:1d::FE degree=3
+DEAL:1d::Total dofs=8
+DEAL:1d::1 1 1 1 0 0 0 0 
+DEAL:1d::0 0 0 0 1 1 1 1 
+DEAL:1d::FE degree=4
+DEAL:1d::Total dofs=10
+DEAL:1d::1 1 1 1 1 0 0 0 0 0 
+DEAL:1d::0 0 0 0 0 1 1 1 1 1 
+DEAL:2d::FE degree=1
+DEAL:2d::Total dofs=12
+DEAL:2d::1 1 1 1 1 1 0 0 0 0 0 0 
+DEAL:2d::0 0 0 0 0 0 1 1 1 1 1 1 
+DEAL:2d::FE degree=2
+DEAL:2d::Total dofs=30
+DEAL:2d::1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 
+DEAL:2d::0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 
+DEAL:2d::FE degree=3
+DEAL:2d::Total dofs=56
+DEAL:2d::1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 
+DEAL:2d::0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 
+DEAL:2d::FE degree=4
+DEAL:2d::Total dofs=90
+DEAL:2d::1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 
+DEAL:2d::0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 
+DEAL:3d::FE degree=1
+DEAL:3d::Total dofs=36
+DEAL:3d::1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 
+DEAL:3d::0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 
+DEAL:3d::FE degree=2
+DEAL:3d::Total dofs=150
+DEAL:3d::1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 
+DEAL:3d::0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 
+DEAL:3d::FE degree=3
+DEAL:3d::Total dofs=392
+DEAL:3d::1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 
+DEAL:3d::0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 
+DEAL:3d::FE degree=4
+DEAL:3d::Total dofs=810
+DEAL:3d::1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 
+DEAL:3d::0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 

tests/mpi/extract_constant_modes_05.cc

@@ -0,0 +1,192 @@
+// ---------------------------------------------------------------------
+//
+// Copyright (C) 2009 - 2018 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.
+//
+// ---------------------------------------------------------------------
+
+
+
+// test DoFTools::extract_constant_modes for multi-physical problems like in
+// step-46 in parallel
+
+#include <deal.II/distributed/tria.h>
+
+#include <deal.II/dofs/dof_accessor.h>
+#include <deal.II/dofs/dof_handler.h>
+#include <deal.II/dofs/dof_renumbering.h>
+#include <deal.II/dofs/dof_tools.h>
+
+#include <deal.II/fe/fe_nothing.h>
+#include <deal.II/fe/fe_q.h>
+#include <deal.II/fe/fe_system.h>
+
+#include <deal.II/grid/grid_generator.h>
+#include <deal.II/grid/tria.h>
+#include <deal.II/grid/tria_accessor.h>
+#include <deal.II/grid/tria_iterator.h>
+
+#include <deal.II/hp/fe_collection.h>
+
+#include "../tests.h"
+
+
+
+template <int dim>
+void
+test(const unsigned int fe_degree)
+{
+  Assert(dim > 1, ExcMessage("This test must run with dim>1"));
+
+  unsigned int myid = Utilities::MPI::this_mpi_process(MPI_COMM_WORLD);
+
+  parallel::distributed::Triangulation<dim> triangulation(MPI_COMM_WORLD);
+
+  Point<dim>                p1, p2;
+  std::vector<unsigned int> sub(dim);
+  sub[0] = 2 * Utilities::MPI::n_mpi_processes(MPI_COMM_WORLD);
+  for (unsigned int i = 0; i < dim; ++i)
+    {
+      if (i > 0)
+        {
+          sub[i] = 1;
+        }
+      p2[i] = 1.0;
+    }
+
+  GridGenerator::subdivided_hyper_rectangle(
+    static_cast<Triangulation<dim> &>(triangulation), sub, p1, p2);
+
+  DoFHandler<dim> dof_handler(triangulation);
+
+  {
+    // set cells to switch between FE_QxFE_Nothing and FE_NothingxFE_Q
+    // alternately
+    unsigned int last_index = 1;
+    for (const auto &cell : dof_handler.active_cell_iterators())
+      {
+        if (cell->is_locally_owned())
+          {
+            cell->set_active_fe_index(last_index = 1 - last_index);
+          }
+      }
+  }
+
+  FESystem<dim>         fe_1(FE_Q<dim>(fe_degree), 1, FE_Nothing<dim>(), 1);
+  FESystem<dim>         fe_2(FE_Nothing<dim>(), 1, FE_Q<dim>(fe_degree), 1);
+  hp::FECollection<dim> fe_collection(fe_1, fe_2);
+
+  dof_handler.distribute_dofs(fe_collection);
+  DoFRenumbering::component_wise(dof_handler);
+
+  if (myid == 0)
+    {
+      deallog << "FE degree=" << fe_degree << std::endl;
+      deallog << "Total dofs=" << dof_handler.n_dofs() << std::endl;
+    }
+
+  // Define set of constant modes
+  std::vector<std::vector<bool>> constant_modes(
+    fe_collection.n_components(),
+    std::vector<bool>(dof_handler.n_locally_owned_dofs(), false));
+
+  if (myid == 0)
+    {
+      // Extract constant modes automatically
+      // DoFTools::extract_constant_modes(dof_handler,
+      //                                  ComponentMask(),
+      //                                  constant_modes);
+
+      // Extract constant modes manually
+      for (unsigned int component = 0; component < fe_collection.n_components();
+           ++component)
+        {
+          AssertDimension(constant_modes[component].size(),
+                          dof_handler.n_locally_owned_dofs());
+
+          const FEValuesExtractors::Scalar component_extractor(component);
+          const ComponentMask              component_mask(
+            fe_collection.component_mask(component_extractor));
+
+          const IndexSet component_index_set =
+            DoFTools::extract_dofs(dof_handler, component_mask);
+
+          for (unsigned int i = 0;
+               i < dof_handler.locally_owned_dofs().n_elements();
+               ++i)
+            {
+              if (component_index_set.is_element(
+                    dof_handler.locally_owned_dofs().nth_index_in_set(i)))
+                {
+                  constant_modes[component][i] = true;
+                }
+              else
+                {
+                  constant_modes[component][i] = false;
+                }
+            }
+        }
+
+      // Print constant modes
+      for (unsigned int i = 0; i < constant_modes.size(); ++i)
+        {
+          for (unsigned int j = 0; j < constant_modes[i].size(); ++j)
+            {
+              deallog << (constant_modes[i][j] ? '1' : '0') << ' ';
+            }
+          deallog << std::endl;
+        }
+    }
+}
+
+
+int
+main(int argc, char *argv[])
+{
+  Utilities::MPI::MPI_InitFinalize mpi_initialization(argc, argv, 1);
+  unsigned int myid = Utilities::MPI::this_mpi_process(MPI_COMM_WORLD);
+  deallog.push(Utilities::int_to_string(myid));
+
+  if (myid == 0)
+    {
+      initlog();
+
+      deallog.push("2d");
+      test<2>(1);
+      test<2>(2);
+      test<2>(3);
+      test<2>(4);
+      deallog.pop();
+
+      deallog.push("3d");
+      test<3>(1);
+      test<3>(2);
+      test<3>(3);
+      test<3>(4);
+      deallog.pop();
+    }
+  else
+    {
+      deallog.push("2d");
+      test<2>(1);
+      test<2>(2);
+      test<2>(3);
+      test<2>(4);
+      deallog.pop();
+
+      deallog.push("3d");
+      test<3>(1);
+      test<3>(2);
+      test<3>(3);
+      test<3>(4);
+      deallog.pop();
+    }
+}