function [ n, x, y, w, s ] = hexagon_lyness_rule04 ( )

%*****************************************************************************80
%
%% hexagon_lyness_rule04() sets the Lyness hexagon quadrature rule #04.
%
%  Licensing:
%
%    This code is distributed under the MIT license. 
%
%  Modified:
%
%    21 April 2019
%
%  Author:
%
%    John Burkardt
%
%  Reference:
%
%    James Lyness, Giovanni Monegato,
%    Quadrature rules for regions having regular hexagonal symmetry,
%    SIAM Journal on Numerical Analysis.
%    Volume 14 Number 2, April 1977, pages 283-295.
%
%  Output:
%
%    integer n, the number of points.
%
%    real x(n), y(n), the points.
%
%    real w(n), the weights.
%
%    integer s, the strength.
%
  n = 7;
  x = zeros ( n, 1 );
  y = zeros ( n, 1 );
  w = zeros ( n, 1 );
  
  x(1) = 0.0;
  y(1) = 0.0;
  w(1) = 0.2559523809523809;

  x(2) = 0.6480740698407861;
  y(2) = 0.3741657386773941;
  w(2) = 0.7440476190476190 / 6.0;
  for i = 3 : 7
    x(i) = cosd ( 60.0 ) * x(i-1) - sind ( 60.0 ) * y(i-1);
    y(i) = sind ( 60.0 ) * x(i-1) + cosd ( 60.0 ) * y(i-1);
    w(i) = w(i-1);
  end
  s = 5;

  return
end
