function [ n_data, x, fx ] = bessel_i1_spherical_values ( n_data )

%*****************************************************************************80
%
%% BESSEL_I1_SPHERICAL_VALUES returns some values of the Spherical Bessel function i1.
%
%  Discussion:
%
%    In Mathematica, the function can be evaluated by:
%
%      Sqrt[Pi/(2*x)] * BesselI[3/2,x]
%
%  Licensing:
%
%    This code is distributed under the GNU LGPL license.
%
%  Modified:
%
%    06 January 2007
%
%  Author:
%
%    John Burkardt
%
%  Reference:
%
%    Milton Abramowitz, Irene Stegun,
%    Handbook of Mathematical Functions,
%    National Bureau of Standards, 1964,
%    LC: QA47.A34,
%    ISBN: 0-486-61272-4.
%
%    Stephen Wolfram,
%    The Mathematica Book,
%    Fourth Edition,
%    Wolfram Media / Cambridge University Press, 1999.
%
%  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 = 21;

  fx_vec = [ ...
    0.03336667857363341E+00, ...
    0.06693371456802954E+00, ...
    0.1354788933285401E+00, ...
    0.2072931911031093E+00, ...
    0.2841280857128948E+00, ...
    0.3678794411714423E+00, ...
    0.4606425870674146E+00, ...
    0.5647736480096238E+00, ...
    0.6829590627779635E+00, ...
    0.8182955028627777E+00, ...
    0.9743827435800610E+00, ...
    1.155432469636406E+00, ...
    1.366396525527973E+00, ...
    1.613118767572064E+00, ...
    1.902515460838681E+00, ...
    2.242790117769266E+00, ...
    2.643689828630357E+00, ...
    3.116811526884873E+00, ...
    3.675968313148932E+00, ...
    4.337627987747642E+00, ...
    5.121438384183637E+00 ];

  x_vec = [ ...
     0.1E+00, ...
     0.2E+00, ...
     0.4E+00, ...
     0.6E+00, ...
     0.8E+00, ...
     1.0E+00, ...
     1.2E+00, ...
     1.4E+00, ...
     1.6E+00, ...
     1.8E+00, ...
     2.0E+00, ...
     2.2E+00, ...
     2.4E+00, ...
     2.6E+00, ...
     2.8E+00, ...
     3.0E+00, ...
     3.2E+00, ...
     3.4E+00, ...
     3.6E+00, ...
     3.8E+00, ...
     4.0E+00 ];

  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
