function [ n_data, x, fx ] = arcsinh_values ( n_data )

%*****************************************************************************80
%
%% ARCSINH_VALUES returns some values of the hyperbolic arc sine function.
%
%  Discussion:
%
%    In Mathematica, the function can be evaluated by:
%
%      ArcSinh[x]
%
%  Licensing:
%
%    This code is distributed under the GNU LGPL license.
%
%  Modified:
%
%    23 June 2007
%
%  Author:
%
%    John Burkardt
%
%  Reference:
%
%    Milton Abramowitz, Irene Stegun,
%    Handbook of Mathematical Functions,
%    National Bureau of Standards, 1964,
%    ISBN: 0-486-61272-4,
%    LC: QA47.A34.
%
%    Stephen Wolfram,
%    The Mathematica Book,
%    Fourth Edition,
%    Cambridge University Press, 1999,
%    ISBN: 0-521-64314-7,
%    LC: QA76.95.W65.
%
%  Parameters:
%
%    Input/output, integer N_DATA.  The user sets N_DATA to 0 before the
%    first call.  On each call, the routine increments N_DATA by 1, and
%    returns the corresponding data; when there is no more data, the
%    output value of N_DATA will be 0 again.
%
%    Output, real X, the argument of the function.
%
%    Output, real FX, the value of the function.
%
  n_max = 20;

  fx_vec = [ ...
    -2.3124383412727526203, ...
    -0.88137358701954302523, ...
     0.00000000000000000000, ...
     0.099834078899207563327, ...
     0.19869011034924140647, ...
     0.29567304756342243910, ...
     0.39003531977071527608, ...
     0.48121182505960344750, ...
     0.56882489873224753010, ...
     0.65266656608235578681, ...
     0.73266825604541086415, ...
     0.80886693565278246251, ...
     0.88137358701954302523, ...
     1.4436354751788103425, ...
     1.8184464592320668235, ...
     2.0947125472611012942, ...
     2.3124383412727526203, ...
     2.9982229502979697388, ...
     5.2983423656105887574, ...
     7.6009027095419886115 ];

  x_vec = [ ...
       -5.0, ...
       -1.0, ...
        0.0, ...
        0.1, ...
        0.2, ...
        0.3, ...
        0.4, ...
        0.5, ...
        0.6, ...
        0.7, ...
        0.8, ...
        0.9, ...
        1.0, ...
        2.0, ...
        3.0, ...
        4.0, ...
        5.0, ...
       10.0, ...
      100.0, ...
     1000.0 ];

  if ( n_data < 0 )
    n_data = 0;
  end

  n_data = n_data + 1;

  if ( n_max < n_data )
    n_data = 0;
    x = 0.0;
    fx = 0.0;
  else
    x = x_vec(n_data);
    fx = fx_vec(n_data);
  end

  return
end