function grid_plot_test ( )

%*****************************************************************************80
%
%% grid_plot_test() tests grid_plot().
%
%  Licensing:
%
%    This code is distributed under the MIT license.
%
%  Modified:
%
%    04 November 2020
%
%  Author:
%
%    John Burkardt
%
  fprintf ( 1, '\n' );
  fprintf ( 1, 'grid_plot_test():\n' );
  fprintf ( 1, '  MATLAB/Octave version %s\n', version ( ) );
  fprintf ( 1, '  grid_plot() plots a grid for polyiamonds.\n' );

  clf ( );

  imin = 1;
  jmin = 1;
  imax = 6;
  jmax = 4;
  r = 0.85;
  color_back = [ 0.9, 0.9, 0.9 ];
  color_tri = [ 1.0, 0.0, 0.0 ];
  number = true;
  grid_plot ( imin, imax, jmin, jmax, r, color_back, color_tri, number );
%
%  Show that you can add things to the plot.
%
  hold ( 'on' );
  ijk = [ 2, 3, 1 ];
  r = 0.70;
  color = 'y';
  label = '*';
  ijk_fill ( ijk, r, color, label );
  hold ( 'off' );

  title ( 'grid plot test' );
  filename = 'grid_plot_test.png';
  print ( '-dpng', filename );
  fprintf ( 1, '  Graphics saved as "%s"\n', filename );
%
%  Terminate.
%
  fprintf ( 1, '\n' );
  fprintf ( 1, 'grid_plot_test():\n' );
  fprintf ( 1, '  Normal end of execution.\n' );

  return
end
