From: Sebastian Proell <sebastian.proell@tum.de>
Date: Thu, 6 Oct 2022 16:15:29 +0000 (+0200)
Subject: Fix bug in FieldTransfer for ghosted vectors
X-Git-Tag: v9.5.0-rc1~903^2
X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=refs%2Fpull%2F14340%2Fhead;p=dealii.git

Fix bug in FieldTransfer for ghosted vectors
---

diff --git a/source/distributed/field_transfer.cc b/source/distributed/field_transfer.cc
index 33d747c637..2c8366d38a 100644
--- a/source/distributed/field_transfer.cc
+++ b/source/distributed/field_transfer.cc
@@ -120,7 +120,7 @@ namespace parallel
 
 
         // Communicate the results.
-        out.compress(dealii::VectorOperation::min);
+        out.compress(dealii::VectorOperation::insert);
 
         // Treat hanging nodes
         std::vector<types::global_dof_index> dof_indices;
diff --git a/tests/hp/field_transfer_04.cc b/tests/hp/field_transfer_04.cc
new file mode 100644
index 0000000000..3efdb4fb07
--- /dev/null
+++ b/tests/hp/field_transfer_04.cc
@@ -0,0 +1,124 @@
+// ---------------------------------------------------------------------
+//
+// 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 use FieldTransfer when multiple cells are changed from
+// FE_Nothing to FE_Q
+
+#include <deal.II/distributed/field_transfer.h>
+
+#include <deal.II/dofs/dof_handler.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/grid/grid_generator.h>
+#include <deal.II/grid/tria.h>
+#include <deal.II/grid/tria_iterator.h>
+
+#include <deal.II/hp/fe_collection.h>
+
+#include "../tests.h"
+
+// FieldTransfer with ghosted vector
+
+int
+main(int argc, char *argv[])
+{
+  Utilities::MPI::MPI_InitFinalize mpi_initialization(argc, argv, 1);
+
+  MPILogInitAll mpi_log;
+
+  parallel::distributed::Triangulation<2> triangulation(MPI_COMM_WORLD);
+  GridGenerator::hyper_cube(triangulation);
+  triangulation.refine_global(2);
+
+  hp::FECollection<2> fe_collection;
+  fe_collection.push_back(FE_Q<2>(1));
+  fe_collection.push_back(FE_Nothing<2>());
+
+  DoFHandler<2> dof_handler(triangulation);
+
+  // Assign FE_Nothing to half of the domain
+  for (auto cell : dof_handler.active_cell_iterators())
+    {
+      if (cell->is_locally_owned())
+        {
+          if (cell->center()[1] < 0.5)
+            {
+              cell->set_active_fe_index(0);
+            }
+          else
+            {
+              cell->set_active_fe_index(1);
+            }
+        }
+    }
+
+  dof_handler.distribute_dofs(fe_collection);
+
+  // Initialize solution
+  auto locally_relevant_dofs =
+    DoFTools::extract_locally_relevant_dofs(dof_handler);
+  LinearAlgebra::distributed::Vector<double> solution(
+    dof_handler.locally_owned_dofs(), locally_relevant_dofs, MPI_COMM_WORLD);
+  const double old_value = 1.;
+  for (unsigned int i = 0; i < solution.local_size(); ++i)
+    solution.local_element(i) = old_value;
+
+  {
+    std::stringstream ss;
+    solution.print(ss);
+    deallog << ss.str() << std::endl;
+  }
+
+  parallel::distributed::experimental::
+    FieldTransfer<2, LinearAlgebra::distributed::Vector<double>>
+      field_transfer(dof_handler);
+  // Assgin FE_Q to all the cells
+  for (auto cell : dof_handler.active_cell_iterators())
+    {
+      if (cell->is_locally_owned())
+        {
+          cell->set_future_fe_index(0);
+        }
+    }
+
+  triangulation.prepare_coarsening_and_refinement();
+
+  solution.update_ghost_values();
+  field_transfer.prepare_for_coarsening_and_refinement(solution, 1);
+
+  triangulation.execute_coarsening_and_refinement();
+
+  dof_handler.distribute_dofs(fe_collection);
+  const unsigned int dofs_per_cell =
+    dof_handler.get_fe_collection().max_dofs_per_cell();
+
+  AffineConstraints<double> affine_constraints;
+  const double              new_value = 2.;
+
+  locally_relevant_dofs.clear();
+  locally_relevant_dofs = DoFTools::extract_locally_relevant_dofs(dof_handler);
+  LinearAlgebra::distributed::Vector<double> new_solution(
+    dof_handler.locally_owned_dofs(), locally_relevant_dofs, MPI_COMM_WORLD);
+  field_transfer.interpolate(new_value, affine_constraints, new_solution);
+
+  {
+    std::stringstream ss;
+    new_solution.print(ss);
+    deallog << ss.str() << std::endl;
+  }
+}
diff --git a/tests/hp/field_transfer_04.with_p4est=true.mpirun=2.output b/tests/hp/field_transfer_04.with_p4est=true.mpirun=2.output
new file mode 100644
index 0000000000..ccd1d62a05
--- /dev/null
+++ b/tests/hp/field_transfer_04.with_p4est=true.mpirun=2.output
@@ -0,0 +1,23 @@
+
+DEAL:0::Process #0
+Local range: [0, 15), global size: 15
+Vector data:
+1.000e+00 1.000e+00 1.000e+00 1.000e+00 1.000e+00 1.000e+00 1.000e+00 1.000e+00 1.000e+00 1.000e+00 1.000e+00 1.000e+00 1.000e+00 1.000e+00 1.000e+00 
+
+DEAL:0::Process #0
+Local range: [0, 15), global size: 25
+Vector data:
+1.000e+00 1.000e+00 1.000e+00 1.000e+00 1.000e+00 1.000e+00 1.000e+00 1.000e+00 1.000e+00 1.000e+00 1.000e+00 1.000e+00 1.000e+00 1.000e+00 1.000e+00 
+
+
+DEAL:1::Process #1
+Local range: [15, 15), global size: 15
+Vector data:
+
+
+DEAL:1::Process #1
+Local range: [15, 25), global size: 25
+Vector data:
+2.000e+00 2.000e+00 2.000e+00 2.000e+00 2.000e+00 2.000e+00 2.000e+00 2.000e+00 2.000e+00 2.000e+00 
+
+
diff --git a/tests/hp/field_transfer_04.with_p4est=true.mpirun=3.output b/tests/hp/field_transfer_04.with_p4est=true.mpirun=3.output
new file mode 100644
index 0000000000..f1cd31a786
--- /dev/null
+++ b/tests/hp/field_transfer_04.with_p4est=true.mpirun=3.output
@@ -0,0 +1,35 @@
+
+DEAL:0::Process #0
+Local range: [0, 9), global size: 15
+Vector data:
+1.000e+00 1.000e+00 1.000e+00 1.000e+00 1.000e+00 1.000e+00 1.000e+00 1.000e+00 1.000e+00 
+
+DEAL:0::Process #0
+Local range: [0, 9), global size: 25
+Vector data:
+1.000e+00 1.000e+00 1.000e+00 1.000e+00 1.000e+00 1.000e+00 1.000e+00 1.000e+00 1.000e+00 
+
+
+DEAL:1::Process #1
+Local range: [9, 15), global size: 15
+Vector data:
+1.000e+00 1.000e+00 1.000e+00 1.000e+00 1.000e+00 1.000e+00 
+
+DEAL:1::Process #1
+Local range: [9, 21), global size: 25
+Vector data:
+1.000e+00 1.000e+00 1.000e+00 1.000e+00 1.000e+00 1.000e+00 2.000e+00 2.000e+00 2.000e+00 2.000e+00 2.000e+00 2.000e+00 
+
+
+
+DEAL:2::Process #2
+Local range: [15, 15), global size: 15
+Vector data:
+
+
+DEAL:2::Process #2
+Local range: [21, 25), global size: 25
+Vector data:
+2.000e+00 2.000e+00 2.000e+00 2.000e+00 
+
+