I trying to cull point in point list. but result is empty
please see my picture
Have you tried flattening the L input?
Without a gh file I can only do guesswork…
your Point parameter contains 30 different lists (0, 1, 2… 29) each of them containing one single point
when you pass it through the Cull Index, it deletes for each branch the item at index 0 and the item at index 29 (your lists have just one item, so it gets deleted)
as @submillimetre suggests, you should flatten the Point Parameter, in such a way you’ll end up with a single list of 30 items (0, 1, 2… 29) of which you can cull the one at index 0 and the one at index 29
to flatten an input: right click on that and select “flatten”