function A = abcd_inc ( )

%*****************************************************************************80
%
%% abcd_inc sets up the incidence matrix associated with a network.
%
%  Licensing:
%
%    This code is distributed under the GNU LGPL license.
%
%  Modified:
%
%    29 February 2020
%
%  Author:
%
%    John Burkardt
%
%  Output:
%
%    integer A(4,4): a sparse incidence matrix.
%
  A = sparse ( [1,2,3,3,4], [2,3,1,4,1], [1,1,1,1,1] );

  return
end

