/* cosine */
/* y in [-1,1] */

var x : real, y : real;
begin
x = random;
assume x>=0 and x<=180;
 if (x <= 45) then
  y = 1 - 0.006508738196*x;
 else 
  if (x <= 90) then
   y = 1 - 0.00017644492*x*x + 0.000000588757*x*x*x;
  else 
    if (x<=135) then
      y = 1.283184584 - 0.0062929908*x - 0.00014148386*x*x +0.000000588757*x*x*x;
    else
      y = 0.17157287528 - 0.006508738196*x;
    endif;
   endif;
 endif;
end