function poisson_cdf_test ( )

%*****************************************************************************80
%
%% POISSON_CDF_TEST tests POISSON_CDF.
%
%  Licensing:
%
%    This code is distributed under the GNU LGPL license.
%
%  Modified:
%
%    14 February 2003
%
%  Author:
%
%    John Burkardt
%
  fprintf ( 1, '\n' );
  fprintf ( 1, 'POISSON_CDF_TEST\n' );
  fprintf ( 1, '  POISSON_CDF evaluates the Poisson CDF,\n' );
  fprintf ( 1, '  POISSON_CDF_INV inverts the Poisson CDF.\n' );
  fprintf ( 1, '  POISSON_PDF evaluates the Poisson PDF.\n' );

  a = 10.0;

  check = poisson_check ( a );

  if ( ~ check );
    fprintf ( 1, '\n' );
    fprintf ( 1, 'POISSON_CDF_TEST - Fatal error!\n' );
    fprintf ( 1, '  The parameters are not legal.\n' );
    return
  end

  fprintf ( 1, '\n' );
  fprintf ( 1, '  PDF parameter A =  %14g\n', a );

  seed = 123456789;

  fprintf ( 1, '\n' );
  fprintf ( 1, '       X            PDF           CDF            CDF_INV\n' );
  fprintf ( 1, '\n' );

  for i = 1 : 10

    [ x, seed ] = poisson_sample ( a, seed );

    pdf = poisson_pdf ( x, a );

    cdf = poisson_cdf ( x, a );

    x2 = poisson_cdf_inv ( cdf, a );

    fprintf ( 1, '  %14d  %14g  %14g  %14d\n', x, pdf, cdf, x2 );

  end

  return
end
