From ccfcc960d721d97b3f790cb8da342c46b3868eca Mon Sep 17 00:00:00 2001
From: Luca Heltai <luca.heltai@sissa.it>
Date: Tue, 9 Apr 2019 23:04:56 +0200
Subject: [PATCH] Test ScratchData for Laplacian (conforming)

---
 tests/meshworker/scratch_data_02.cc           | 159 ++++++++++++++++++
 ...02.with_muparser=on.with_umfpack=on.output |   2 +
 2 files changed, 161 insertions(+)
 create mode 100644 tests/meshworker/scratch_data_02.cc
 create mode 100644 tests/meshworker/scratch_data_02.with_muparser=on.with_umfpack=on.output

diff --git a/tests/meshworker/scratch_data_02.cc b/tests/meshworker/scratch_data_02.cc
new file mode 100644
index 0000000000..d74bc90b05
--- /dev/null
+++ b/tests/meshworker/scratch_data_02.cc
@@ -0,0 +1,159 @@
+/* ---------------------------------------------------------------------
+ *
+ * Copyright (C) 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.md at
+ * the top level directory of deal.II.
+ *
+ * ---------------------------------------------------------------------
+ */
+
+// Check mesh_loop + ScratchData for Laplacian (conforming)
+
+#include <deal.II/base/function_parser.h>
+#include <deal.II/base/patterns.h>
+#include <deal.II/base/thread_management.h>
+
+#include <deal.II/dofs/dof_tools.h>
+
+#include <deal.II/fe/fe_dgq.h>
+
+#include <deal.II/grid/grid_generator.h>
+#include <deal.II/grid/grid_out.h>
+#include <deal.II/grid/grid_tools.h>
+#include <deal.II/grid/grid_tools_cache.h>
+#include <deal.II/grid/tria.h>
+#include <deal.II/grid/tria_accessor.h>
+#include <deal.II/grid/tria_iterator.h>
+
+#include <deal.II/lac/affine_constraints.h>
+#include <deal.II/lac/sparse_direct.h>
+
+#include <deal.II/meshworker/copy_data.h>
+#include <deal.II/meshworker/mesh_loop.h>
+#include <deal.II/meshworker/scratch_data.h>
+
+#include <deal.II/numerics/data_out.h>
+#include <deal.II/numerics/vector_tools.h>
+
+#include <cmath>
+#include <fstream>
+#include <iostream>
+#include <unordered_map>
+
+#include "../tests.h"
+
+using namespace MeshWorker;
+
+template <int dim, int spacedim>
+void
+test()
+{
+  Triangulation<dim, spacedim> tria;
+  FE_Q<dim, spacedim>          fe(1);
+  DoFHandler<dim, spacedim>    dh(tria);
+
+  FunctionParser<spacedim> rhs_function("1");
+  FunctionParser<spacedim> boundary_function("0");
+
+  AffineConstraints<double> constraints;
+
+  GridGenerator::hyper_cube(tria);
+  tria.refine_global(5);
+  tria.execute_coarsening_and_refinement();
+  dh.distribute_dofs(fe);
+
+
+  DoFTools::make_hanging_node_constraints(dh, constraints);
+  VectorTools::interpolate_boundary_values(dh,
+                                           0,
+                                           boundary_function,
+                                           constraints);
+
+  constraints.close();
+
+  SparsityPattern sparsity;
+
+  {
+    DynamicSparsityPattern dsp(dh.n_dofs(), dh.n_dofs());
+    DoFTools::make_flux_sparsity_pattern(dh, dsp);
+    sparsity.copy_from(dsp);
+  }
+
+  SparseMatrix<double> matrix;
+  matrix.reinit(sparsity);
+
+  Vector<double> solution(dh.n_dofs());
+  Vector<double> rhs(dh.n_dofs());
+
+  QGauss<dim>     quad(3);
+  QGauss<dim - 1> face_quad(3);
+
+  UpdateFlags cell_flags = update_values | update_gradients |
+                           update_quadrature_points | update_JxW_values;
+  UpdateFlags face_flags = update_JxW_values;
+
+  using ScratchData = MeshWorker::ScratchData<dim, spacedim>;
+  using CopyData    = MeshWorker::CopyData<1, 1, 1>;
+
+  ScratchData scratch(fe, quad, cell_flags, face_quad, face_flags);
+  CopyData    copy(fe.dofs_per_cell);
+
+  auto cell = dh.begin_active();
+  auto endc = dh.end();
+
+  typedef decltype(cell) Iterator;
+
+  auto cell_worker =
+    [&rhs_function](const Iterator &cell, ScratchData &s, CopyData &c) {
+      const auto &fev = s.reinit(cell);
+      const auto &JxW = s.get_JxW_values();
+      const auto &p   = s.get_quadrature_points();
+
+      c = 0;
+
+      c.local_dof_indices[0] = s.get_local_dof_indices();
+
+      for (unsigned int q = 0; q < p.size(); ++q)
+        for (unsigned int i = 0; i < fev.dofs_per_cell; ++i)
+          {
+            for (unsigned int j = 0; j < fev.dofs_per_cell; ++j)
+              {
+                c.matrices[0](i, j) +=
+                  fev.shape_grad(i, q) * fev.shape_grad(j, q) * JxW[q];
+              }
+            c.vectors[0](i) +=
+              fev.shape_value(i, q) * rhs_function.value(p[q]) * JxW[q];
+          }
+    };
+
+  auto copier = [&constraints, &matrix, &rhs](const CopyData &c) {
+    constraints.distribute_local_to_global(
+      c.matrices[0], c.vectors[0], c.local_dof_indices[0], matrix, rhs);
+  };
+
+  mesh_loop(cell, endc, cell_worker, copier, scratch, copy, assemble_own_cells);
+
+  SparseDirectUMFPACK inv;
+  inv.initialize(matrix);
+
+  inv.vmult(solution, rhs);
+  constraints.distribute(solution);
+
+  deallog << "Linfty norm of solution: " << solution.linfty_norm() << std::endl;
+}
+
+
+int
+main()
+{
+  initlog();
+
+  test<2, 2>();
+}
diff --git a/tests/meshworker/scratch_data_02.with_muparser=on.with_umfpack=on.output b/tests/meshworker/scratch_data_02.with_muparser=on.with_umfpack=on.output
new file mode 100644
index 0000000000..b5ad838ee8
--- /dev/null
+++ b/tests/meshworker/scratch_data_02.with_muparser=on.with_umfpack=on.output
@@ -0,0 +1,2 @@
+
+DEAL::Linfty norm of solution: 0.0737281
-- 
2.39.5