clear
window 0
defaults
r=mod([0:143],4)+1
sort r
t=mod([0:143],36)*10
x = r*cosd(t)
y = r*sind(t)
z = exp(-r/2)*cosd(180*(r-1))
set
 %yimagticlength 2
 %xnumbersheight 5
 %ynumbersheight 5
 xdropfirstnumber 1
 xdroplastnumber 1
 ydropfirstnumber 1
 ydroplastnumber 1
 colormap topo256

scales\-messages -5 5 -5 5
density\dithering x y z