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x=linspace(0,2*%pi,nn);

y=0.1+[sin(linspace(0,%pi,15)),1.5*sin(linspace(0,%pi,10)),sin(linspace(0,%pi,15))];
cosphi=dup(cos(x),length(y));
sinphi=dup(sin(x),length(y));
f=dup(y',length(x));
x1=f.*cosphi;     y1=f.*sinphi;
z=dup(linspace(-2,2,prod(size(y)))',prod(size(x)));
plot3d2(x1,y1,z,-1,35,70);