Hi,
Lists!
I need to reverse only some curves of a list.
I do know their indexes ( in my case 0,1,17,18)
I am struggling, I made it in a very long way, too silly yo be happy with.
There must be a more clever one 
Basically, given a list, I want to take some elements of it (by index), modify them and re-insert at the same index.
Thanks in advance.
