Inserting into a list within a list python

Question

I am trying to insert something into a list within a list and I couldn't figure out how to go doing that.

For example, I have a list of lists:

List1 = [[10, 13, 17], [3, 5, 1]]

and I want to insert 5 into sublist with index 0 after element 13 so it would look like this:

List1 = [[10, 13, 5, 17], [3, 5, 1]]
#                 ^

use list.insert(index, value) function – Advay Umare Feb 08 '18 at 08:47 — Advay Umare, Feb 08 '18 at 08:47
`List1[0].insert(2, 5)` – juanpa.arrivillaga Feb 08 '18 at 08:48 — juanpa.arrivillaga, Feb 08 '18 at 08:48

Vivek Kalyanarangan · Answer 1 · 2018-02-08T09:40:10.860

2

This will do it. Using .insert() allows you to specify index as well the element and you can do it inplace. No need to assign the output.

List1 = [[10,13,5,17],[3,5,1]]
List1[0].insert(2,5)
print(List1)

Output

[[10, 13, 5, 17], [3, 5, 1]]

edited Feb 08 '18 at 09:40

answered Feb 08 '18 at 08:49

1 Answers1