Merge pull request #13170 from jppelteret/filtered_iterator_test_01

Add some more tests for iterator filters

doc/news/changes/minor/2022010531SimonStickoJean-PaulPelteret

@@ -0,0 +1,6 @@
+Fixed: The FEInterfaceValues class is now made compatible with filtered
+iterators. Specifically, it is now possible to call FEInterfaceValues::reinit()
+with the active `cell` being a filtered iterator and the type returned by
+`cell->neighbor()` being some other non-filtered iterator type.
+<br>
+(Simon Sticko, Jean-Paul Pelteret, 2022/01/05)

include/deal.II/fe/fe_interface_values.h

@@ -1405,14 +1405,14 @@ class FEInterfaceValues
    * @param[in] sub_face_no_neighbor Like `sub_face_no`, just for the
    *   neighboring cell.
    */
-  template <class CellIteratorType>
+  template <class CellIteratorType, class CellNeighborIteratorType>
   void
-  reinit(const CellIteratorType &                         cell,
-         const unsigned int                               face_no,
-         const unsigned int                               sub_face_no,
-         const typename identity<CellIteratorType>::type &cell_neighbor,
-         const unsigned int                               face_no_neighbor,
-         const unsigned int                               sub_face_no_neighbor);
+  reinit(const CellIteratorType &        cell,
+         const unsigned int              face_no,
+         const unsigned int              sub_face_no,
+         const CellNeighborIteratorType &cell_neighbor,
+         const unsigned int              face_no_neighbor,
+         const unsigned int              sub_face_no_neighbor);
 
   /**
    * Re-initialize this object to be used on an interface given by a single face
@@ -2028,15 +2028,15 @@ FEInterfaceValues<dim, spacedim>::FEInterfaceValues(
 
 
 template <int dim, int spacedim>
-template <class CellIteratorType>
+template <class CellIteratorType, class CellNeighborIteratorType>
 void
 FEInterfaceValues<dim, spacedim>::reinit(
-  const CellIteratorType &                         cell,
-  const unsigned int                               face_no,
-  const unsigned int                               sub_face_no,
-  const typename identity<CellIteratorType>::type &cell_neighbor,
-  const unsigned int                               face_no_neighbor,
-  const unsigned int                               sub_face_no_neighbor)
+  const CellIteratorType &        cell,
+  const unsigned int              face_no,
+  const unsigned int              sub_face_no,
+  const CellNeighborIteratorType &cell_neighbor,
+  const unsigned int              face_no_neighbor,
+  const unsigned int              sub_face_no_neighbor)
 {
   if (sub_face_no == numbers::invalid_unsigned_int)
     {

tests/grid/filtered_iterator_07.cc

@@ -0,0 +1,129 @@
+// ---------------------------------------------------------------------
+//
+// 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 we can create iterators filtered using ActiveFEIndexEqualTo.
+
+
+#include <deal.II/dofs/dof_handler.h>
+
+#include <deal.II/fe/fe_q.h>
+
+#include <deal.II/grid/filtered_iterator.h>
+#include <deal.II/grid/grid_generator.h>
+
+#include <deal.II/hp/fe_collection.h>
+
+#include "../tests.h"
+
+
+template <int dim, int spacedim>
+void
+test()
+{
+  Triangulation<dim, spacedim> tria;
+  GridGenerator::hyper_cube(tria, 0, 1, true);
+  tria.refine_global(1);
+
+  const FE_Q<dim, spacedim> fe(1);
+
+  DoFHandler<dim, spacedim> dof_handler(tria);
+  dof_handler.distribute_dofs(fe);
+
+  int n_cells_visited = 0;
+  for (const auto &cell :
+       filter_iterators(dof_handler.active_cell_iterators(),
+                        IteratorFilters::ActiveFEIndexEqualTo(0)))
+    {
+      ++n_cells_visited;
+      (void)cell;
+    }
+
+  Assert(n_cells_visited == Utilities::fixed_power<dim>(2),
+         ExcMessage("Wrong number of cells visited."));
+
+  n_cells_visited = 0;
+  for (const auto &cell :
+       filter_iterators(dof_handler.active_cell_iterators(),
+                        IteratorFilters::ActiveFEIndexEqualTo(1)))
+    {
+      ++n_cells_visited;
+      (void)cell;
+    }
+
+  Assert(n_cells_visited == 0, ExcMessage("Wrong number of cells visited."));
+}
+
+
+template <int dim, int spacedim>
+void
+test_hp()
+{
+  Triangulation<dim, spacedim> tria;
+  GridGenerator::hyper_cube(tria, 0, 1, true);
+  tria.refine_global(1);
+
+  const hp::FECollection<dim, spacedim> fe_collection{FE_Q<dim, spacedim>(1),
+                                                      FE_Q<dim, spacedim>(1)};
+
+  DoFHandler<dim, spacedim> dof_handler(tria);
+
+  for (auto &cell : dof_handler.active_cell_iterators())
+    if (cell == dof_handler.begin_active())
+      cell->set_active_fe_index(1);
+    else
+      cell->set_active_fe_index(0);
+
+  dof_handler.distribute_dofs(fe_collection);
+
+  int n_cells_visited = 0;
+  for (const auto &cell :
+       filter_iterators(dof_handler.active_cell_iterators(),
+                        IteratorFilters::ActiveFEIndexEqualTo(0)))
+    {
+      ++n_cells_visited;
+      (void)cell;
+    }
+
+  Assert(n_cells_visited == Utilities::fixed_power<dim>(2) - 1,
+         ExcMessage("Wrong number of cells visited."));
+
+  n_cells_visited = 0;
+  for (const auto &cell :
+       filter_iterators(dof_handler.active_cell_iterators(),
+                        IteratorFilters::ActiveFEIndexEqualTo(1)))
+    {
+      ++n_cells_visited;
+      (void)cell;
+    }
+
+  Assert(n_cells_visited == 1, ExcMessage("Wrong number of cells visited."));
+}
+
+
+int
+main()
+{
+  initlog();
+
+  test<2, 2>();
+  test<2, 3>();
+  test<3, 3>();
+
+  test_hp<2, 2>();
+  test_hp<2, 3>();
+  test_hp<3, 3>();
+
+  deallog << "OK" << std::endl;
+}

tests/grid/filtered_iterator_07.output

@@ -0,0 +1,2 @@
+
+DEAL::OK

tests/grid/filtered_iterator_07_operator.cc

@@ -0,0 +1,128 @@
+// ---------------------------------------------------------------------
+//
+// 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 we can create iterators filtered using ActiveFEIndexEqualTo.
+//
+// Compared to filtered_iterator_07, this test checks the availability
+// of operator| to create the filter.
+
+
+#include <deal.II/dofs/dof_handler.h>
+
+#include <deal.II/fe/fe_q.h>
+
+#include <deal.II/grid/filtered_iterator.h>
+#include <deal.II/grid/grid_generator.h>
+
+#include <deal.II/hp/fe_collection.h>
+
+#include "../tests.h"
+
+
+template <int dim, int spacedim>
+void
+test()
+{
+  Triangulation<dim, spacedim> tria;
+  GridGenerator::hyper_cube(tria, 0, 1, true);
+  tria.refine_global(1);
+
+  const FE_Q<dim, spacedim> fe(1);
+
+  DoFHandler<dim, spacedim> dof_handler(tria);
+  dof_handler.distribute_dofs(fe);
+
+  int n_cells_visited = 0;
+  for (const auto &cell : dof_handler.active_cell_iterators() |
+                            IteratorFilters::ActiveFEIndexEqualTo(0))
+    {
+      ++n_cells_visited;
+      (void)cell;
+    }
+
+  Assert(n_cells_visited == Utilities::fixed_power<dim>(2),
+         ExcMessage("Wrong number of cells visited."));
+
+  n_cells_visited = 0;
+  for (const auto &cell : dof_handler.active_cell_iterators() |
+                            IteratorFilters::ActiveFEIndexEqualTo(1))
+    {
+      ++n_cells_visited;
+      (void)cell;
+    }
+
+  Assert(n_cells_visited == 0, ExcMessage("Wrong number of cells visited."));
+}
+
+
+template <int dim, int spacedim>
+void
+test_hp()
+{
+  Triangulation<dim, spacedim> tria;
+  GridGenerator::hyper_cube(tria, 0, 1, true);
+  tria.refine_global(1);
+
+  const hp::FECollection<dim, spacedim> fe_collection{FE_Q<dim, spacedim>(1),
+                                                      FE_Q<dim, spacedim>(1)};
+
+  DoFHandler<dim, spacedim> dof_handler(tria);
+
+  for (auto &cell : dof_handler.active_cell_iterators())
+    if (cell == dof_handler.begin_active())
+      cell->set_active_fe_index(1);
+    else
+      cell->set_active_fe_index(0);
+
+  dof_handler.distribute_dofs(fe_collection);
+
+  int n_cells_visited = 0;
+  for (const auto &cell : dof_handler.active_cell_iterators() |
+                            IteratorFilters::ActiveFEIndexEqualTo(0))
+    {
+      ++n_cells_visited;
+      (void)cell;
+    }
+
+  Assert(n_cells_visited == Utilities::fixed_power<dim>(2) - 1,
+         ExcMessage("Wrong number of cells visited."));
+
+  n_cells_visited = 0;
+  for (const auto &cell : dof_handler.active_cell_iterators() |
+                            IteratorFilters::ActiveFEIndexEqualTo(1))
+    {
+      ++n_cells_visited;
+      (void)cell;
+    }
+
+  Assert(n_cells_visited == 1, ExcMessage("Wrong number of cells visited."));
+}
+
+
+int
+main()
+{
+  initlog();
+
+  test<2, 2>();
+  test<2, 3>();
+  test<3, 3>();
+
+  test_hp<2, 2>();
+  test_hp<2, 3>();
+  test_hp<3, 3>();
+
+  deallog << "OK" << std::endl;
+}

tests/grid/filtered_iterator_07_operator.output

@@ -0,0 +1,2 @@
+
+DEAL::OK