gnuplot> set style data points
gnuplot> plot "sparsity_pattern.1"
@endcode
+
+Another practice based on
+<a href="http://www.gnuplot.info/">GNUPLOT</a> is trying to
+print out the mesh with locations and numbering of the support
+points where you need to include GridOut and MappingQ1 first.
+The code for this is:
+@code
+ std::ofstream out("gnuplot.gpl");
+ out << "plot '-' using 1:2 with lines, "
+ << "'-' with labels point pt 2 offset 1,1"
+ << std::endl;
+ GridOut().write_gnuplot (triangulation, out);
+ out << "e" << std::endl;
+ const int dim = 2;
+ std::map<types::global_dof_index, Point<dim> > support_points;
+ DoFTools::map_dofs_to_support_points (MappingQ1<dim>(),
+ dof_handler,
+ support_points);
+ DoFTools::write_gnuplot_dof_support_point_info(out,
+ support_points);
+ out << "e" << std::endl;
+@endcode
+After run the code, we can get a file called gnuplot.gpl. To view this
+file, we can run the following code in the command line:
+@code
+gnuplot -p gnuplot.gpl
+@endcode.