function edge_check_test ( )

%*****************************************************************************80
%
%% edge_check_test() tests edge_check().
%
%  Licensing:
%
%    This code is distributed under the MIT license.
%
%  Modified:
%
%    24 December 2015
%
%  Author:
%
%    John Burkardt
%
  fprintf ( 1, '\n' );
  fprintf ( 1, 'edge_check test():\n' );
  fprintf ( 1, '  edge_check() checks a graph described by edges.\n' );
  fprintf ( 1, '\n' );
  fprintf ( 1, '  Check?  Nodes  Edges    EdgeList\n' );
  fprintf ( 1, '\n' );
  
  for test = 1 : 6

    if ( test == 1 )
      node_num = -5;
      edge_num = 3;
      edge_list = [ ...
        1, 2, 3; ...
        2, 3, 1 ];
    elseif ( test == 2 )
      node_num = 3;
      edge_num = -1;
      edge_list = [ ...
        1, 2, 3; ...
        2, 3, 1 ];
    elseif ( test == 3 )
      node_num = 3;
      edge_num = 3;
      edge_list = [ ...
        1, 2, 3; ...
        2, 3, 4 ];
    elseif ( test == 4 )
      node_num = 3;
      edge_num = 3;
      edge_list = [ ...
        1, 2, 3; ...
        2, 2, 1 ];
    elseif ( test == 5 )
      node_num = 3;
      edge_num = 3;
      edge_list = [ ...
        1, 2, 2; ...
        2, 3, 1 ];
    elseif ( test == 6 )
      node_num = 3;
      edge_num = 3;
      edge_list = [ ...
        1, 2, 3; ...
        2, 3, 1 ];
    end

    fprintf ( 1, '\n' );
    check = edge_check ( node_num, edge_num, edge_list );
    fprintf ( 1, '      %5s     %2d     %2d\n', ...
      mat2str ( check ), node_num, edge_num );
    i4mat_print ( 2, edge_num, edge_list, '  Edge list of graph:' );
    
  end

  return
end
