function sphere_cvt_test ( )

%*****************************************************************************80
%
%% SPHERE_CVT_TEST tests SPHERE_CVT.
%
%  Licensing:
%
%    This code is distributed under the GNU LGPL license. 
%
%  Modified:
%
%    03 May 2010
%
%  Author:
%
%    John Burkardt
%
  timestamp ( );
  fprintf ( 1, '\n' );
  fprintf ( 1, 'SPHERE_CVT_TEST\n' );
  fprintf ( 1, '  MATLAB version:\n' );
  fprintf ( 1, '  Test the SPHERE_CVT library.\n' );

  sphere_cvt_test01 ( );
%
%  Terminate.
%
  fprintf ( 1, '\n' );
  fprintf ( 1, 'SPHERE_CVT_TEST:\n' );
  fprintf ( 1, '  Normal end of execution.\n' );

  fprintf ( 1, '\n' );
  timestamp ( );

  return
end
function sphere_cvt_test01 ( )

%*****************************************************************************80
%
%% SPHERE_CVT_TEST01 demonstrates the computation of a CVT on the unit sphere.
%
%  Licensing:
%
%    This code is distributed under the GNU LGPL license. 
%
%  Modified:
%
%    03 May 2010
%
%  Author:
%
%    John Burkardt
%
  fprintf ( 1, '\n' );
  fprintf ( 1, 'SPHERE_CVT_TEST01\n' );
  fprintf ( 1, '  Demonstrate the iterative computation of a CVT\n' );
  fprintf ( 1, '  (Centroidal Voronoi Tessellation) on the unit sphere.\n' );
%
%  Choose a random set of points on the unit sphere.
%
  n = 100;
  seed = 123456789;
  [ xyz, seed ] = uniform_on_sphere01_map ( 3, n, seed );
  r8mat_transpose_print ( 3, n, xyz, '  Initial points:' );

  figure ( 1 )
  sphere_voronoi_plot ( n, xyz )

  for i = 1 : 50

    centroid = sphere_cvt_step ( n, xyz );

    xyz(1:3,1:n) = centroid(1:3,1:n);

  end

  r8mat_transpose_print ( 3, n, xyz, '  Final points:' );
%
%  Plot the final data.
%
  figure ( 2 )
  sphere_voronoi_plot ( n, xyz );

  return
end