--- /dev/null
+// ---------------------------------------------------------------------
+//
+// Copyright (C) 2016 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.
+//
+// ---------------------------------------------------------------------
+
+
+
+// this tests the correctness of matrix_diagonal_inverse of
+// MatrixFreeOperators::MassOperator for FE_Q_Hierarchical
+// This caused problems with positivity of the lumped mass matrix
+
+#include "../tests.h"
+
+#include <deal.II/base/logstream.h>
+#include <deal.II/base/utilities.h>
+#include <deal.II/base/function.h>
+#include <deal.II/distributed/tria.h>
+#include <deal.II/grid/grid_generator.h>
+#include <deal.II/grid/tria_boundary_lib.h>
+#include <deal.II/dofs/dof_tools.h>
+#include <deal.II/dofs/dof_handler.h>
+#include <deal.II/lac/constraint_matrix.h>
+#include <deal.II/lac/trilinos_sparse_matrix.h>
+#include <deal.II/lac/trilinos_sparsity_pattern.h>
+#include <deal.II/matrix_free/operators.h>
+#include <deal.II/fe/fe_q_hierarchical.h>
+#include <deal.II/fe/fe_values.h>
+#include <deal.II/numerics/vector_tools.h>
+
+#include <iostream>
+
+
+
+
+template <int dim, int fe_degree>
+void test ()
+{
+ typedef double number;
+
+ parallel::distributed::Triangulation<dim> tria (MPI_COMM_WORLD);
+ GridGenerator::hyper_cube (tria);
+ tria.refine_global(3);
+
+ FE_Q_Hierarchical<dim> fe (fe_degree);
+ DoFHandler<dim> dof (tria);
+ dof.distribute_dofs(fe);
+
+ IndexSet owned_set = dof.locally_owned_dofs();
+ IndexSet relevant_set;
+ DoFTools::extract_locally_relevant_dofs (dof, relevant_set);
+
+ ConstraintMatrix constraints (relevant_set);
+ DoFTools::make_hanging_node_constraints(dof, constraints);
+ constraints.close();
+
+ deallog << "Testing " << dof.get_fe().get_name() << std::endl;
+ //std::cout << "Number of cells: " << tria.n_global_active_cells() << std::endl;
+ //std::cout << "Number of degrees of freedom: " << dof.n_dofs() << std::endl;
+ //std::cout << "Number of constraints: " << constraints.n_constraints() << std::endl;
+
+ MatrixFree<dim,number> mf_data;
+ {
+ const QGauss<1> quad (fe_degree+2);
+ typename MatrixFree<dim,number>::AdditionalData data;
+ data.mpi_communicator = MPI_COMM_WORLD;
+ data.tasks_parallel_scheme =
+ MatrixFree<dim,number>::AdditionalData::none;
+ data.tasks_block_size = 7;
+ mf_data.reinit (dof, constraints, quad, data);
+ }
+
+ MatrixFreeOperators::MassOperator<dim,fe_degree, fe_degree+2, 1, number> mf;
+ mf.initialize(mf_data);
+ mf.compute_diagonal();
+ const LinearAlgebra::distributed::Vector<double> &diagonal
+ = mf.get_matrix_diagonal_inverse()->get_vector();
+
+ LinearAlgebra::distributed::Vector<number> in, out, ref;
+ mf_data.initialize_dof_vector (in);
+ out.reinit (in);
+ ref.reinit (in);
+
+ for (unsigned int i=0; i<in.local_size(); ++i)
+ {
+ const unsigned int glob_index =
+ owned_set.nth_index_in_set (i);
+ if (constraints.is_constrained(glob_index))
+ continue;
+ in.local_element(i) = 1.;
+ }
+
+ in.update_ghost_values();
+ out = diagonal;
+
+ // assemble trilinos sparse matrix with
+ // (v, u) for reference
+ TrilinosWrappers::SparseMatrix sparse_matrix;
+ {
+ TrilinosWrappers::SparsityPattern csp (owned_set, MPI_COMM_WORLD);
+ DoFTools::make_sparsity_pattern (dof, csp, constraints, true,
+ Utilities::MPI::this_mpi_process(MPI_COMM_WORLD));
+ csp.compress();
+ sparse_matrix.reinit (csp);
+ }
+ {
+ QGauss<dim> quadrature_formula(fe_degree+2);
+
+ FEValues<dim> fe_values (dof.get_fe(), quadrature_formula,
+ update_values | update_gradients |
+ update_JxW_values);
+
+ const unsigned int dofs_per_cell = dof.get_fe().dofs_per_cell;
+ const unsigned int n_q_points = quadrature_formula.size();
+
+ FullMatrix<double> cell_matrix (dofs_per_cell, dofs_per_cell);
+ std::vector<types::global_dof_index> local_dof_indices (dofs_per_cell);
+
+ typename DoFHandler<dim>::active_cell_iterator
+ cell = dof.begin_active(),
+ endc = dof.end();
+ for (; cell!=endc; ++cell)
+ if (cell->is_locally_owned())
+ {
+ cell_matrix = 0;
+ fe_values.reinit (cell);
+
+ for (unsigned int q_point=0; q_point<n_q_points; ++q_point)
+ for (unsigned int i=0; i<dofs_per_cell; ++i)
+ {
+ for (unsigned int j=0; j<dofs_per_cell; ++j)
+ cell_matrix(i,j) += (fe_values.shape_value(i,q_point) *
+ fe_values.shape_value(j,q_point)) *
+ fe_values.JxW(q_point);
+ }
+
+ cell->get_dof_indices(local_dof_indices);
+ constraints.distribute_local_to_global (cell_matrix,
+ local_dof_indices,
+ sparse_matrix);
+ }
+ }
+ sparse_matrix.compress(VectorOperation::add);
+
+ sparse_matrix.vmult (ref, in);
+
+ for (unsigned int i=0; i<ref.local_size(); ++i)
+ {
+ const unsigned int glob_index =
+ owned_set.nth_index_in_set (i);
+ if (constraints.is_constrained(glob_index))
+ ref.local_element(i)=1.;
+ else
+ ref.local_element(i) = 1./ref.local_element(i);
+ }
+ ref.compress(VectorOperation::insert);
+
+ out -= ref;
+ const double diff_norm = out.linfty_norm();
+
+ deallog << "Norm of difference: " << diff_norm << std::endl;
+ deallog << "l2_norm: " << diagonal.l2_norm() << std::endl;
+ deallog << "l1_norm: " << diagonal.l1_norm() << std::endl;
+ deallog << "linfty_norm: " << diagonal.linfty_norm() << std::endl << std::endl;
+}
+
+
+int main (int argc, char **argv)
+{
+ Utilities::MPI::MPI_InitFinalize mpi_initialization (argc, argv, testing_max_num_threads());
+
+ mpi_initlog();
+
+ deallog.push("2d");
+ test<2,1>();
+ test<2,2>();
+ deallog.pop();
+
+ deallog.push("3d");
+ test<3,1>();
+ test<3,2>();
+ deallog.pop();
+}
+