New test case

diff --git a/tests/matrix_free/matrix_vector_25.cc b/tests/matrix_free/matrix_vector_25.cc
new file mode 100644 (file)
index 0000000..77f2315
--- /dev/null
+++ b/tests/matrix_free/matrix_vector_25.cc
@@ -0,0 +1,140 @@
+// ------------------------------------------------------------------------
+//
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2024 by the deal.II authors
+//
+// This file is part of the deal.II library.
+//
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
+//
+// ------------------------------------------------------------------------
+
+
+
+// similar test as matrix_vector_01, but using ArrayView instead of
+// dealii::Vector
+
+#include <deal.II/base/logstream.h>
+#include <deal.II/base/utilities.h>
+
+#include <deal.II/dofs/dof_handler.h>
+#include <deal.II/dofs/dof_tools.h>
+
+#include <deal.II/fe/fe_q.h>
+#include <deal.II/fe/fe_values.h>
+
+#include <deal.II/grid/grid_generator.h>
+#include <deal.II/grid/manifold_lib.h>
+#include <deal.II/grid/tria.h>
+
+#include <deal.II/lac/affine_constraints.h>
+#include <deal.II/lac/dynamic_sparsity_pattern.h>
+#include <deal.II/lac/sparse_matrix.h>
+#include <deal.II/lac/vector.h>
+
+#include <deal.II/numerics/vector_tools.h>
+
+#include <iostream>
+
+#include "../tests.h"
+
+#include "matrix_vector_mf.h"
+
+
+template <int dim, int fe_degree>
+void
+test();
+
+
+
+template <int dim, typename number>
+void
+do_test(const DoFHandler<dim>           &dof,
+        const AffineConstraints<double> &constraints)
+{
+  deallog << "Testing " << dof.get_fe().get_name() << std::endl;
+
+  MappingQ<dim>           mapping(dof.get_fe().degree);
+  MatrixFree<dim, number> mf_data;
+  {
+    const QGauss<1> quad(dof.get_fe().degree + 1);
+    typename MatrixFree<dim, number>::AdditionalData data;
+    data.tasks_parallel_scheme =
+      MatrixFree<dim, number>::AdditionalData::partition_partition;
+
+    mf_data.reinit(mapping, dof, constraints, quad, data);
+  }
+
+  Vector<number> in(dof.n_dofs()), out(dof.n_dofs());
+  Vector<number> in_dist(dof.n_dofs());
+  Vector<number> out_dist(in_dist);
+
+  for (unsigned int i = 0; i < dof.n_dofs(); ++i)
+    {
+      if (constraints.is_constrained(i))
+        continue;
+      const double entry = random_value<double>();
+      in(i)              = entry;
+      in_dist(i)         = entry;
+    }
+
+  MatrixFreeTest<dim, -1, number, Vector<number>, 0> mf_reference(mf_data);
+  mf_reference.vmult(out, in);
+
+  MatrixFreeTest<dim, -1, number, dealii::ArrayView<number>, 0> mf(mf_data);
+  ArrayView<number> out_view = make_array_view(out_dist);
+  mf.vmult(out_view, make_array_view(in_dist));
+
+
+  {
+    out_dist -= out;
+    const double diff_norm = out_dist.linfty_norm() / out.linfty_norm();
+    deallog << "Norm of difference: " << diff_norm << std::endl << std::endl;
+  }
+
+  mf.vmult(out_view, make_array_view(in_dist));
+
+  {
+    out_dist -= out;
+    const double diff_norm = out_dist.linfty_norm() / out.linfty_norm();
+    deallog << "Norm of difference: " << diff_norm << std::endl << std::endl;
+  }
+}
+
+template <int dim>
+void
+test(const unsigned int fe_degree)
+{
+  Triangulation<dim> tria;
+  GridGenerator::hyper_cube(tria);
+  tria.refine_global(5 - dim);
+
+  FE_Q<dim>       fe(fe_degree);
+  DoFHandler<dim> dof(tria);
+  dof.distribute_dofs(fe);
+  AffineConstraints<double> constraints;
+  constraints.close();
+
+  do_test<dim, double>(dof, constraints);
+}
+
+
+
+int
+main()
+{
+  initlog();
+
+  {
+    deallog.push("2d");
+    test<2>(1);
+    test<2>(2);
+    deallog.pop();
+    deallog.push("3d");
+    test<3>(2);
+    deallog.pop();
+  }
+}

diff --git a/tests/matrix_free/matrix_vector_25.output b/tests/matrix_free/matrix_vector_25.output
new file mode 100644 (file)
index 0000000..90931f1
--- /dev/null
+++ b/tests/matrix_free/matrix_vector_25.output
@@ -0,0 +1,16 @@
+
+DEAL:2d::Testing FE_Q<2>(1)
+DEAL:2d::Norm of difference: 0.00000
+DEAL:2d::
+DEAL:2d::Norm of difference: 0.00000
+DEAL:2d::
+DEAL:2d::Testing FE_Q<2>(2)
+DEAL:2d::Norm of difference: 0.00000
+DEAL:2d::
+DEAL:2d::Norm of difference: 0.00000
+DEAL:2d::
+DEAL:3d::Testing FE_Q<3>(2)
+DEAL:3d::Norm of difference: 0.00000
+DEAL:3d::
+DEAL:3d::Norm of difference: 0.00000
+DEAL:3d::

diff --git a/tests/matrix_free/matrix_vector_mf.h b/tests/matrix_free/matrix_vector_mf.h
index 954007d8c2c5692f7edcf98d504a410dd5547354..fc4f2587a662492fef98cad33ac25e7b3524d5c9 100644 (file)
--- a/tests/matrix_free/matrix_vector_mf.h
+++ b/tests/matrix_free/matrix_vector_mf.h
@@ -133,7 +133,12 @@ public:
   void
   vmult(VectorType &dst, const VectorType &src) const
   {
-    dst = 0;
+    if constexpr (std::is_same_v<VectorType, dealii::ArrayView<Number>>)
+      for (unsigned int i = 0; i < dst.size(); ++i)
+        dst[i] = 0;
+    else
+      dst = 0;
+
     const std::function<
       void(const MatrixFree<dim, typename VectorType::value_type> &,
            VectorType &,