Sinusoidal point along the z-axis maintaining circular shape

basic question here: I tried several methods but none seem working.
I am trying to move points of a circle in z axis to create a regular closed sine wave in a circle shape, but after connecting a interpolate node (toggle true to periodic in interpolate node) curve will close with a straight line or in a (21.8 KB)
irregular way, not following the sinusoidal shape.


thanks for your time

Range creates n+1 values:

you can right click on Range N input and write as Expression x-1 to get 9 steps instead of 10, which will result in 10 points (9.5 KB)

P.S. Lofting the circle and sine wave works well. (9.6 KB)
Actually, not so well if you look closely…

P.P.S. This fixes the lofts except alternate surface normals are flipped. (16.1 KB)

So flip alternate surfaces… GH is so hard! :rofl: (18.5 KB)


This is a brilliant solution. Thank you.