function value = cc_weight ( order, i )

%% CC_WEIGHT returns the I-th Clenshaw Curtis weight.
%
%  Licensing:
%
%    This code is distributed under the GNU LGPL license.
%
%  Modified:
%
%    14 March 2007
%
%  Author:
%
%    John Burkardt
%
%  Parameters:
%
%    Input, integer ORDER, the order of the rule.
%
%    Input, integer I, the index of the desired weight.  1 <= I <= ORDER.
%
%    Output, real VALUE, the I-th weight in the
%    Clenshaw-Curtis rule of order ORDER.
%
  if ( order < 1 )
    fprintf ( 1, '\n' );
    fprintf ( 1, 'CC_WEIGHT - Fatal error!\n' );
    fprintf ( 1, '  ORDER < 1.\n' );
    error ( 'CC_WEIGHT - Fatal error!' );
  end

  if ( order == 1 )
    value = 2.0;
    return
  end

  value = 1.0;

  for j = 1 : floor ( order - 1 ) / 2

    if ( 2 * j == ( order - 1 ) )
      b = 1.0;
    else
      b = 2.0;
    end

    angle = ( 2 * j * ( i - 1 ) ) * pi / ( order - 1 );

    value = value - b * cos ( angle ) / ( 4 * j * j - 1 );

  end

  if ( i == 1 )
    value =           value / ( order - 1 );
  elseif ( i <= order - 1 )
    value = 2.0 * value / ( order - 1 );
  elseif ( i == order )
    value =           value / ( order - 1 );
  end

  return
end