mesh
 radial trisection
 trisection blocks, 4
 numz 1
  zblock 1 4.0 interval 1
 numr 3 
  rblock 1 2. interval 4
  rblock 2 3. interval 4
  rblock 3 5. interval 4
 numa 1
  ablock 1 360. interval 32
 end
end
