function network_graph ( )

%*****************************************************************************80
%
%% network_graph plots a network.
%
%  Discussion:
%
%    The graph function creates a graph, and the plot function recognizes it,
%    displaying nodes, edges, and numeric node labels.
%
%  Licensing:
%
%    This code is distributed under the GNU LGPL license.
%
%  Modified:
%
%    21 September 2018
%
%  Author:
%
%    John Burkardt
%
  fprintf ( 1, '\n' );
  fprintf ( 1, 'network_graph:\n' );
  fprintf ( 1, '  MATLAB version\n' );
  fprintf ( 1, '  Plot a network as a graph.\n' );

  s = [ 1, 1, 2, 2, 3, 4, 4, 5, 5, 5, 6, 7, 8,  9,  9, 10 ];
  t = [ 2, 3, 4, 5, 4, 5, 6, 6, 7, 8, 7, 8, 9, 10, 11, 11 ];
  G = graph ( s, t )
  plot ( G )
%
%  Save a copy as a PNG file.
%
  filename = 'network_graph.png';
  print ( '-dpng', filename );
  fprintf ( 1, '\n' );
  fprintf ( 1, '  Graphics saved as "%s"\n', filename );
%
%  Terminate.
%
  fprintf ( 1, '\n' );
  fprintf ( 1, 'network_graph:\n' );
  fprintf ( 1, '  Normal end of execution.\n' );

  return
end

