Python – How to Split List into Sublists by Number of Elements

listpythonsplit

In python, if I have the list of elements

l = ['a', 'b', 'c', 'd', 'e', 'f']

and a list of numbers

n = [2, 1, 3]

How I can split the list l by the numbers in n ?

And get this list of lists

[['a', 'b'], ['c'], ['d', 'e', 'f']]

Best Answer

You could use islice:

>>> from itertools import islice
>>> l = ['a', 'b', 'c', 'd', 'e', 'f']
>>> n = [2, 1, 3]
>>> it = iter(l)
>>> out = [list(islice(it, size)) for size in n]
>>> out
[['a', 'b'], ['c'], ['d', 'e', 'f']]

Related Solutions

Python – How to Split a List into Smaller Lists

A = [1,2,3,4,5,6]
B = A[:len(A)//2]
C = A[len(A)//2:]

If you want a function:

def split_list(a_list):
    half = len(a_list)//2
    return a_list[:half], a_list[half:]

A = [1,2,3,4,5,6]
B, C = split_list(A)

Python List – How to Split a List into Sublists of Decreasing Size

Use a simple list comprehension, which iterates over the length of original list. Also, I have used variable name lst, since list is a python type.

Here you go:

>>> lst = [0,1,2,3]
>>> [lst[i:] for i in range(len(lst))]
[[0, 1, 2, 3], [1, 2, 3], [2, 3], [3]]

Best Answer

Related Solutions

Python – How to Split a List into Smaller Lists

Python List – How to Split a List into Sublists of Decreasing Size

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