]> https://gitweb.dealii.org/ - dealii.git/commitdiff
New test, but doesn't work right now.
authorWolfgang Bangerth <bangerth@math.tamu.edu>
Tue, 2 May 2006 23:07:24 +0000 (23:07 +0000)
committerWolfgang Bangerth <bangerth@math.tamu.edu>
Tue, 2 May 2006 23:07:24 +0000 (23:07 +0000)
git-svn-id: https://svn.dealii.org/trunk@12996 0785d39b-7218-0410-832d-ea1e28bc413d

tests/hp/step-3.cc [new file with mode: 0644]

diff --git a/tests/hp/step-3.cc b/tests/hp/step-3.cc
new file mode 100644 (file)
index 0000000..68a32f2
--- /dev/null
@@ -0,0 +1,226 @@
+//----------------------------  step-3.cc  ---------------------------
+//    $Id$
+//    Version: $Name$ 
+//
+//    Copyright (C) 2005, 2006 by the deal.II authors
+//
+//    This file is subject to QPL and may not be  distributed
+//    without copyright and license information. Please refer
+//    to the file deal.II/doc/license.html for the  text  and
+//    further information on this license.
+//
+//----------------------------  step-3.cc  ---------------------------
+
+
+// a hp-ified version of step-3
+
+
+#include <base/logstream.h>
+#include <grid/tria.h>
+#include <dofs/dof_handler.h>
+#include <grid/grid_generator.h>
+
+#include <grid/tria_accessor.h>
+#include <grid/tria_iterator.h>
+#include <dofs/dof_accessor.h>
+
+#include <fe/fe_q.h>
+
+#include <dofs/dof_tools.h>
+
+#include <fe/hp_fe_values.h>
+#include <base/quadrature_lib.h>
+
+#include <base/function.h>
+#include <numerics/vectors.h>
+#include <numerics/matrices.h>
+
+#include <lac/vector.h>
+#include <lac/full_matrix.h>
+#include <lac/sparse_matrix.h>
+#include <lac/solver_cg.h>
+#include <lac/precondition.h>
+
+#include <numerics/data_out.h>
+#include <fstream>
+#include <iostream>
+
+std::ofstream logfile("step-3/output");
+
+
+
+
+class LaplaceProblem 
+{
+  public:
+    LaplaceProblem ();
+
+    void run ();
+    
+  private:
+    void make_grid_and_dofs ();
+    void assemble_system ();
+    void solve ();
+    void output_results () const;
+
+    Triangulation<2>     triangulation;
+    hp::FECollection<2>              fe;
+    hp::DoFHandler<2>        dof_handler;
+
+    SparsityPattern      sparsity_pattern;
+    SparseMatrix<double> system_matrix;
+
+    Vector<double>       solution;
+    Vector<double>       system_rhs;
+};
+
+
+LaplaceProblem::LaplaceProblem () :
+                fe (FE_Q<2>(1)),
+               dof_handler (triangulation)
+{}
+
+
+
+void LaplaceProblem::make_grid_and_dofs ()
+{
+  GridGenerator::hyper_cube (triangulation, -1, 1);
+  triangulation.refine_global (5);
+  deallog << "Number of active cells: "
+           << triangulation.n_active_cells()
+           << std::endl;
+  deallog << "Total number of cells: "
+           << triangulation.n_cells()
+           << std::endl;
+  
+  dof_handler.distribute_dofs (fe);
+  deallog << "Number of degrees of freedom: "
+           << dof_handler.n_dofs()
+           << std::endl;
+
+  sparsity_pattern.reinit (dof_handler.n_dofs(),
+                          dof_handler.n_dofs(),
+                          dof_handler.max_couplings_between_dofs());
+  DoFTools::make_sparsity_pattern (dof_handler, sparsity_pattern);
+  sparsity_pattern.compress();
+
+  system_matrix.reinit (sparsity_pattern);
+
+  solution.reinit (dof_handler.n_dofs());
+  system_rhs.reinit (dof_handler.n_dofs());
+}
+
+
+
+void LaplaceProblem::assemble_system () 
+{
+  hp::QCollection<2>  quadrature_formula(QGauss<2>(2));
+  hp::FEValues<2> x_fe_values (fe, quadrature_formula, 
+                        update_values | update_gradients | update_JxW_values);
+  
+  const unsigned int   dofs_per_cell = fe[0].dofs_per_cell;
+  const unsigned int   n_q_points    = quadrature_formula[0].n_quadrature_points;
+
+  FullMatrix<double>   cell_matrix (dofs_per_cell, dofs_per_cell);
+  Vector<double>       cell_rhs (dofs_per_cell);
+
+  std::vector<unsigned int> local_dof_indices (dofs_per_cell);
+
+  hp::DoFHandler<2>::active_cell_iterator
+    cell = dof_handler.begin_active(),
+    endc = dof_handler.end();
+  for (; cell!=endc; ++cell)
+    {
+      x_fe_values.reinit (cell);
+
+      const FEValues<2> &fe_values = x_fe_values.get_present_fe_values();
+      
+      cell_matrix = 0;
+      cell_rhs = 0;
+
+      for (unsigned int i=0; i<dofs_per_cell; ++i)
+       for (unsigned int j=0; j<dofs_per_cell; ++j)
+         for (unsigned int q_point=0; q_point<n_q_points; ++q_point)
+           cell_matrix(i,j) += (fe_values.shape_grad (i, q_point) *
+                                fe_values.shape_grad (j, q_point) *
+                                fe_values.JxW (q_point));
+
+      for (unsigned int i=0; i<dofs_per_cell; ++i)
+       for (unsigned int q_point=0; q_point<n_q_points; ++q_point)
+         cell_rhs(i) += (fe_values.shape_value (i, q_point) *
+                         1 *
+                         fe_values.JxW (q_point));
+
+      cell->get_dof_indices (local_dof_indices);
+
+      for (unsigned int i=0; i<dofs_per_cell; ++i)
+       for (unsigned int j=0; j<dofs_per_cell; ++j)
+         system_matrix.add (local_dof_indices[i],
+                            local_dof_indices[j],
+                            cell_matrix(i,j));
+
+      for (unsigned int i=0; i<dofs_per_cell; ++i)
+       system_rhs(local_dof_indices[i]) += cell_rhs(i);
+    }
+
+
+  std::map<unsigned int,double> boundary_values;
+  VectorTools::interpolate_boundary_values (dof_handler,
+                                           0,
+                                           ZeroFunction<2>(),
+                                           boundary_values);
+  MatrixTools::apply_boundary_values (boundary_values,
+                                     system_matrix,
+                                     solution,
+                                     system_rhs);
+}
+
+
+
+void LaplaceProblem::solve () 
+{
+  SolverControl           solver_control (1000, 1e-12);
+  SolverCG<>              cg (solver_control);
+
+  cg.solve (system_matrix, solution, system_rhs,
+           PreconditionIdentity());
+}
+
+
+
+void LaplaceProblem::output_results () const
+{
+  DataOut<2,hp::DoFHandler<2> > data_out;
+  data_out.attach_dof_handler (dof_handler);
+  data_out.add_data_vector (solution, "solution");
+  data_out.build_patches ();
+
+  std::ofstream output ("solution.gpl");
+  data_out.write_gnuplot (output);
+}
+
+
+
+void LaplaceProblem::run () 
+{
+  make_grid_and_dofs ();
+  assemble_system ();
+  solve ();
+  output_results ();
+}
+
+
+
+int main () 
+{
+  logfile.precision(2);
+  
+  deallog.attach(logfile);
+  deallog.depth_console(0);
+  deallog.threshold_double(1.e-10);  
+
+  LaplaceProblem laplace_problem;
+  laplace_problem.run ();
+
+  return 0;
+}

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