From d38bd37ea74f9f4254c863823a26a357137bcd33 Mon Sep 17 00:00:00 2001
From: Wolfgang Bangerth <bangerth@colostate.edu>
Date: Wed, 5 Sep 2018 13:42:58 -0600
Subject: [PATCH] Add a test.

---
 tests/mpi/hp_unify_dof_indices_07.cc          | 109 ++++++++++++++++++
 .../hp_unify_dof_indices_07.mpirun=1.output   |   7 ++
 .../hp_unify_dof_indices_07.mpirun=2.output   |  15 +++
 3 files changed, 131 insertions(+)
 create mode 100644 tests/mpi/hp_unify_dof_indices_07.cc
 create mode 100644 tests/mpi/hp_unify_dof_indices_07.mpirun=1.output
 create mode 100644 tests/mpi/hp_unify_dof_indices_07.mpirun=2.output

diff --git a/tests/mpi/hp_unify_dof_indices_07.cc b/tests/mpi/hp_unify_dof_indices_07.cc
new file mode 100644
index 0000000000..758170f388
--- /dev/null
+++ b/tests/mpi/hp_unify_dof_indices_07.cc
@@ -0,0 +1,109 @@
+// ---------------------------------------------------------------------
+//
+// Copyright (C) 2017 - 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 at
+// the top level of the deal.II distribution.
+//
+// ---------------------------------------------------------------------
+
+
+
+// have a 2x1 coarse mesh (or 2x1x1) and verify DoF indices in the hp
+// case with an FECollection that contains multiple copies of the same
+// FE_Q(2) element. in the sequential case, the hp code will unify DoF
+// indices on boundaries between locally owned subdomains; in early
+// versions of the parallel hp support, we don't do that, but the
+// final version now does
+//
+// this test gives a different perspective on this issue. in the _01
+// test, we output the DoF indices on all cells as viewed by different
+// processors. here, we also compute hanging node constraints which
+// however should all have been resolved to identities during DoF
+// index unification -- so there should be no constraints at all here
+
+
+#include <deal.II/base/tensor.h>
+#include <deal.II/base/utilities.h>
+
+#include <deal.II/distributed/tria.h>
+
+#include <deal.II/dofs/dof_tools.h>
+
+#include <deal.II/fe/fe_q.h>
+
+#include <deal.II/grid/grid_generator.h>
+#include <deal.II/grid/intergrid_map.h>
+#include <deal.II/grid/tria_accessor.h>
+#include <deal.II/grid/tria_iterator.h>
+
+#include <deal.II/hp/dof_handler.h>
+#include <deal.II/hp/fe_collection.h>
+
+#include <numeric>
+
+#include "../tests.h"
+
+
+template <int dim>
+void
+test()
+{
+  parallel::distributed::Triangulation<dim> triangulation(
+    MPI_COMM_WORLD, Triangulation<dim>::limit_level_difference_at_vertices);
+
+  std::vector<unsigned int> reps(dim, 1U);
+  reps[0] = 2;
+  Point<dim> top_right;
+  for (unsigned int d = 0; d < dim; ++d)
+    top_right[d] = (d == 0 ? 2 : 1);
+  GridGenerator::subdivided_hyper_rectangle(triangulation,
+                                            reps,
+                                            Point<dim>(),
+                                            top_right);
+  Assert(triangulation.n_global_active_cells() == 2, ExcInternalError());
+  Assert(triangulation.n_active_cells() == 2, ExcInternalError());
+
+  hp::FECollection<dim> fe;
+  fe.push_back(FE_Q<dim>(2));
+  fe.push_back(FE_Q<dim>(2));
+
+  hp::DoFHandler<dim> dof_handler(triangulation);
+  if (dof_handler.begin_active()->is_locally_owned())
+    dof_handler.begin_active()->set_active_fe_index(0);
+  if ((++dof_handler.begin_active())->is_locally_owned())
+    (++dof_handler.begin_active())->set_active_fe_index(1);
+  dof_handler.distribute_dofs(fe);
+
+  ConstraintMatrix constraints;
+  DoFTools::make_hanging_node_constraints(dof_handler, constraints);
+  constraints.close();
+
+  deallog << "Processor: " << Utilities::MPI::this_mpi_process(MPI_COMM_WORLD)
+          << std::endl;
+  deallog << "n_dofs: " << dof_handler.n_dofs() << std::endl;
+  deallog << "n_constraints: " << constraints.n_constraints() << std::endl;
+  constraints.print(deallog.get_file_stream());
+}
+
+
+int
+main(int argc, char *argv[])
+{
+  Utilities::MPI::MPI_InitFinalize mpi_initialization(argc, argv, 1);
+  MPILogInitAll                    log;
+
+  deallog.push("2d");
+  test<2>();
+  deallog.pop();
+
+  deallog.push("3d");
+  test<3>();
+  deallog.pop();
+}
diff --git a/tests/mpi/hp_unify_dof_indices_07.mpirun=1.output b/tests/mpi/hp_unify_dof_indices_07.mpirun=1.output
new file mode 100644
index 0000000000..e7baa981e0
--- /dev/null
+++ b/tests/mpi/hp_unify_dof_indices_07.mpirun=1.output
@@ -0,0 +1,7 @@
+
+DEAL:0:2d::Processor: 0
+DEAL:0:2d::n_dofs: 15
+DEAL:0:2d::n_constraints: 0
+DEAL:0:3d::Processor: 0
+DEAL:0:3d::n_dofs: 45
+DEAL:0:3d::n_constraints: 0
diff --git a/tests/mpi/hp_unify_dof_indices_07.mpirun=2.output b/tests/mpi/hp_unify_dof_indices_07.mpirun=2.output
new file mode 100644
index 0000000000..d568fdc29a
--- /dev/null
+++ b/tests/mpi/hp_unify_dof_indices_07.mpirun=2.output
@@ -0,0 +1,15 @@
+
+DEAL:0:2d::Processor: 0
+DEAL:0:2d::n_dofs: 15
+DEAL:0:2d::n_constraints: 0
+DEAL:0:3d::Processor: 0
+DEAL:0:3d::n_dofs: 45
+DEAL:0:3d::n_constraints: 0
+
+DEAL:1:2d::Processor: 1
+DEAL:1:2d::n_dofs: 15
+DEAL:1:2d::n_constraints: 0
+DEAL:1:3d::Processor: 1
+DEAL:1:3d::n_dofs: 45
+DEAL:1:3d::n_constraints: 0
+
-- 
2.39.5