Splitting a list into uneven groups?

Question

I know how to split a list into even groups, but I\'m having trouble splitting it into uneven groups.

Essentially here is what I have: some list, let\'s call it

Answer 1

Using list-comprehensions together with slicing and sum() function (all basic and built-in tools of python):

mylist = [1,2,3,4,5,6,7,8,9,10]
seclist = [2,4,6]

[mylist[sum(seclist[:i]):sum(seclist[:i+1])] for i in range(len(seclist))]

#output:
[[1, 2], [3, 4, 5, 6], [7, 8, 9, 10]]

---

If seclist is very long and you wish to be more efficient use numpy.cumsum() first:

import numpy as np
cumlist = np.hstack((0, np.cumsum(seclist)))
[mylist[cumlist[i]:cumlist[i+1]] for i in range(len(cumlist)-1)]

and get the same results