o<rcone> sub
   #<rmax>   = #1 (= 10)
   #<rmin>   = #2 (=  1)
    #<del_r> = #3 (=  0.001)
    #<del_z> = #4 (= -0.001)
#<del_theta> = #5 (= +1 1:CCW -1:CW)
    #<frate> = #6 (=100)

#<r> = #<rmax>
#<z> = 0
#<theta> = 0

f #<frate>

g0 x#<r> y0
o<10wh> while [#<r> gt #<rmin>]
         #<r> = [#<r> - #<del_r>]
         #<theta> = [#<theta> + #<del_theta>]
         #<x> = [#<r> * cos[#<theta>]]
         #<y> = [#<r> * sin[#<theta>]]
         #<z> = [#<z> + #<del_z>]
         ;#<x> = [#<rmax> * cos[#<theta>]]
         ;#<y> = [#<rmax> * sin[#<theta>]]
         ;#<z> = [0 + #<del_z>]
         g1 x#<x> y#<y> z#<z>
o<10wh> endwhile
o<rcone> endsub