function r8ri_print_some_test ( )

%*****************************************************************************80
%
%% R8RI_PRINT_SOME_TEST tests R8RI_PRINT_SOME.
%
%  Discussion:
%
%    The matrix is related to the discrete 2D Laplacian on a 3x3 grid.
%
%  Licensing:
%
%    This code is distributed under the MIT license. 
%
%  Modified:
%
%    08 July 2016
%
%  Author:
%
%    John Burkardt
%
  n = 9;
  nz = 34;

  a = [ ...
    4.0,  4.0,  4.0,  4.0,  4.0, ...
    4.0,  4.0,  4.0,  4.0,  0.0, ...
   -1.0, -1.0, -1.0, -1.0, -1.0, ...
   -1.0, -1.0, -1.0, -1.0, -1.0, ...
   -1.0, -1.0, -1.0, -1.0, -1.0, ...
   -1.0, -1.0, -1.0, -1.0, -1.0, ...
   -1.0, -1.0, -1.0, -1.0 ];

  ija = [ ...
     11, 13, 16, 18, 21, ...
     25, 28, 30, 33, 35, ...
      2,  4,  1,  3,  5, ...
      2,  6,  1,  5,  7, ...
      2,  4,  6,  8,  3, ...
      5,  9,  4,  8,  5, ...
      7,  9,  6,  8 ];

  fprintf ( 1, '\n' );
  fprintf ( 1, 'R8RI_PRINT_SOME_TEST\n' );
  fprintf ( 1, '  R8RI_PRINT_SOME prints some of an R8RI matrix.\n' );
  fprintf ( 1, '\n' );
  fprintf ( 1, '  Matrix order N = %d\n', n );
  fprintf ( 1, '  Storage NZ =     %d\n', nz );

  r8ri_print_some ( n, nz, ija, a, 1, 4, 9, 6, '  Rows 1-9, Cols 4-6:' );

  return
end
