Ketinit();
Setparent(Cdyname()+"fig");
Setketcindyjs(["Scale=2.0","Nolabel=all","Lo=n","Color=white","Grid=false","Axes=false","Figure=y"]);//no ketjs
Setwindow([-3,3],[-4,3]);
Fontsize("n");

y=-3.8; // no ketjs on
x=-2.5;
space=6/4;
Movetojs(Text71,[x,y],12); 
Movetojs(Text73,[x+space,y],12);
Movetojs(Text74,[x+space*2,y],12);
Movetojs(Text72,[x+space*3,y],12); //no ketjs off

p0=[0,0];
r=2.5;
Circledata("1",[p0,r],["dr,1.5","Num=100"]);

an=Animationparam(0,60,[-100000,100000]);

th=an*pi/180;
p1=r*[cos(th),sin(th)];
Listplot("1",[p0,p1],["dr,1.5","Color=red"]);
fun="(0.5+0.1*abs(t)/(2*pi))*[cos(t),sin(t)]";
rng=Assign("t=[0,th]",["th",th]);
if(abs(th)>0,
  Paramplot("1",fun,rng);
  Arrowhead("1",Ptend(gp1),"gp1",[0.5]);
);
Expr([-r,r],"e","\theta="+Sprintf(an,2)+"^{\circ}",["Size=1"]);

Figpdf();
Windispg();