function i4_to_hex_digit_test ( )

%*****************************************************************************80
%
%% i4_to_hex_digit_test() tests i4_to_hex_digit().
%
%  Licensing:
%
%    This code is distributed under the MIT license.
%
%  Modified:
%
%    24 June 2022
%
%  Author:
%
%    John Burkardt
%
  fprintf ( 1, '\n' );
  fprintf ( 1, 'i4_to_hex_digit_test():\n' );
  fprintf ( 1, '  i4_to_hex_digit() converts integer -> hex digit\n' );
  fprintf ( 1, '\n' );
  fprintf ( 1, '  I4  Hex  I4\n' );
  fprintf ( 1, '\n' );

  for i4 = 0 : 15

    hex = i4_to_hex_digit ( i4 );
    i42 = hex_digit_to_i4 ( hex );

    fprintf ( 1, '  %2d     %s  %2d\n', i4, hex, i42 );

  end

  return
end
