input gdd;
input gdd-rep;
input gdd-lbl;
input gdd-tra;
input svgnames;

lblPreambule := "\usepackage[frenchb]{babel}"       &
                "\usepackage[garamond]{mathdesign}" &
                "\usepackage{amsmath}";

input gdd-fct;
input gdd-plt;

labeloffset := 6;
gddU:=1.5cm;

vardef r(expr t)  = 4*cos(t/3)*cos(t/3)*cos(t/3)  enddef;

vardef rp(expr t) = (r(t)*cos(t),r(t)*sin(t)) enddef;

def traceDoubleVecteur(expr o,d)= drawdblarrow ((o-d)--(o+d)) gddEnPlace enddef;

def avecCrayon(expr t,c) = withpen pencircle scaled t withcolor c enddef;


a = arccos(1/sqrt(3));



beginfig(1);


 Repere(8,8,2,4,1,1);
 Axes; 
 Debut; 
  Graduations; Unites(1);

  drawoptions(withcolor Gainsboro);


  trace CourbeEnPolaires(r,0,3Pi,450)
    avecCrayon(1.5,Crimson);

  drawoptions(withcolor LightGoldenrod);

  pointe Point(0,0);

 Fin;


endfig;

end