YUV_Plot_2

>function F () ...
 global C;
 Kr = 0.299;
 Kg = 0.587;
 Kb = 0.114;
 ab = (1 - Kb) / Kg;
 ar = (1 - Kr) / Kg;
 for v=-127:127;
   for u=-127:127;
 cBlue = (1 + 2*(u*ab/127.0) - (v/127.0)) / (1 + 2*ab);
 cRed = (1 + 2*(v*ar/127.0) - (u/127.0)) / (1 + 2*ar);
 temp = 2 / (ab + ar);
 cGreen = (1 - cRed - cBlue) * temp;
 if ( cRed < 0.0 || cRed > 1.0 || cGreen < 0.0 || cGreen > 1.0 || cBlue < 0.0 || cBlue > 1.0) then
   cRed = 0.0;
   cGreen = 0.0;
   cBlue = 0.0;
 endif;
 C[v+128,u+128]=rgb(cRed,cGreen,cBlue);
   end;
 end;
 endfunction

>C = ones(255,255);
>F()
>plot2d(none,-127,127,-127,127); ...
 plotrgb(C):