
# input parameters: r=1 or 2.
# deg=degree.

fn=
!for i = $deg to 0 step -1
 fn=$fn+$(c$r$[$i+1])*x^$i*y^$[$deg-$i]
!next i

num=!rawmath $fn
fn=
!for i = $deg to 0 step -1
 fn=$fn+$(c$r$[$i+$deg+2])*x^$i*y^$[$deg-$i]
!next i

den=!rawmath $fn

