function x2 (t) return 2^t * cos (PI/2-2*PI*t);  // blue
function y2 (t) return 2^t * sin (PI/2-2*PI*t);

svg_open (200,200,100,100,'einheit=0.5');
  svg_kreuz (10);
  svg_kurve (x2,y2,  2, 3 
             ,'zoom=10', 'sf=blue' );
  for(i=0;i<12;i++) {
    t=i/12;
    svg_strecke(0,0, x2(t)*10*4,y2(t)*10*4 ,'sd=0.1');
  }
w=-ld(1/2);svg_punkt ( x2(0)*40 ,y2(0)*40,"sf=red","sd=1"); svg_text(x2(0)*40,y2(0)*40,'C');
w=-ld(1/2);svg_punkt ( x2(w)*40 ,y2(w)*40,"sf=red","sd=1"); svg_text(x2(w)*40,y2(w)*40,"C'");
w=-ld(2/3);svg_punkt ( x2(w)*40, y2(w)*40,"sf=red","sd=1"); svg_text(x2(w)*40,y2(w)*40,'G');
w=-ld(3/4);svg_punkt ( x2(w)*40, y2(w)*40,"sf=red","sd=1"); svg_text(x2(w)*40,y2(w)*40,'F');
w=-ld(4/5);svg_punkt ( x2(w)*40, y2(w)*40,"sf=red","sd=1"); svg_text(x2(w)*40,y2(w)*40,'E');
w=-ld(3/5);svg_punkt ( x2(w)*40, y2(w)*40,"sf=red","sd=1"); svg_text(x2(w)*40,y2(w)*40,'A');
w=-ld(8/9);svg_punkt ( x2(w)*40, y2(w)*40,"sf=red","sd=1"); svg_text(x2(w)*40,y2(w)*40,'D');
svg_close 'r.svg';