function r8gd_print_some ( n, ndiag, offset, a, ilo, jlo, ihi, jhi, title )

%*****************************************************************************80
%
%% R8GD_PRINT_SOME prints some of a R8GD matrix.
%
%  Discussion:
%
%    The R8GD storage format is suitable for matrices whose only nonzero entries
%    occur along a few diagonals, but for which these diagonals are not all
%    close enough to the main diagonal for band storage to be efficient.
%
%    In that case, we assign the main diagonal the offset value 0.
%    Each successive superdiagonal gets an offset value 1 higher, until
%    the highest superdiagonal (the A(1,N) entry) is assigned the offset N-1.
%    Similarly, the subdiagonals are assigned offsets of -1 through -(N-1).
%
%    Now, assuming that only a few of these diagonals contain nonzeros,
%    then for the I-th diagonal to be saved, we stored its offset in
%    OFFSET(I), and its entries in column I of the matrix.  
%
%  Licensing:
%
%    This code is distributed under the GNU LGPL license.
%
%  Modified:
%
%    07 April 2006
%
%  Author:
%
%    John Burkardt
%
%  Parameters:
%
%    Input, integer N, the number of columns of the matrix.
%    N must be positive.
%
%    Input, integer NDIAG, the number of diagonals of the matrix
%    that are stored in the array.
%    NDIAG must be at least 1, and no more than 2 * N - 1.
%
%    Input, integer OFFSET(NDIAG), the offsets for the diagonal storage.
%
%    Input, real A(N,NDIAG), the R8GD matrix.
%
%    Input, integer ILO, JLO, IHI, JHI, the first row and
%    column, and the last row and column to be printed.
%
%    Input, string TITLE, a title.
%
  fprintf ( 1, '\n' );
  fprintf ( 1, '%s\n', title );

  incx = 5;
%
%  Print the columns of the matrix, in strips of 5.
%
  for j2lo = jlo : incx : jhi

    j2hi = j2lo + incx - 1;
    j2hi = min ( j2hi, n );
    j2hi = min ( j2hi, jhi );

    inc = j2hi + 1 - j2lo;

    fprintf ( 1, '\n' );
    fprintf ( 1, '  Col: ' );

    for j = j2lo : j2hi
      fprintf ( 1, '%7d       ', j );
    end

    fprintf ( 1, '\n' );
    fprintf ( 1, '  Row\n' );
    fprintf ( 1, '  ---\n' );
%
%  Determine the range of the rows in this strip.
%
    i2lo = max ( ilo, 1 );
    i2hi = min ( ihi, n );

    for i = i2lo : i2hi

      fprintf ( 1, '%4d  ', i );
%
%  Print out (up to) 5 entries in row I, that lie in the current strip.
%
      for j2 = 1 : inc

        j = j2lo - 1 + j2;

        aij = 0.0E+00;
        off = j - i;
        for diag = 1 : ndiag
          if ( off == offset(diag) )
            aij = a(i,diag);
          end
        end

        fprintf ( 1, '%12g  ', aij );

      end

      fprintf ( 1, '\n' );

    end

  end

  return
end
