how to remove an item in a list of list of string using index in python

Question

input:

letters = [['a', 'b', 'c'], ['a', 'b', 'c']]
row= 0
column=0

output

[['b', 'c'], ['a', 'b', 'c']]

I tried to do this:

letters[0].remove(0)

but it gives me a value error, while when I use pop like this:

letters[0].pop(0)

it does what I need but the problem with pop is that it returns me something while I just need the item to be removed

`del` takes an index or slice, so `del letters[0][0]` should do what you're asking for with no return value. — Peter DeGlopper, Jul 25 '22 at 17:31
If this column in pandas, It's raising errors because your column getting different length with other columns — I'mahdi, Jul 25 '22 at 17:31
Does this answer your question? [How to remove an element from a list by index](https://stackoverflow.com/questions/627435/how-to-remove-an-element-from-a-list-by-index) — Pranav Hosangadi, Jul 25 '22 at 17:33
I will try what you suggested @user14773854 and let you know if it did work! — Sarah Ahmadi, Jul 25 '22 at 17:34
That constraint doesn't make much sense in any practical context, but in that case `pop()` is the best option. If you're truly supposed to modify the list. — Peter DeGlopper, Jul 25 '22 at 19:52

score 3 · Answer 1 · answered Jul 25 '22 at 17:31

3

letters = [['a', 'b', 'c'], ['a', 'b', 'c']]

del list1[0][0]

use the del keyword

answered Jul 25 '22 at 17:31

Caleb Bunch

score 1 · Accepted Answer · answered Jul 25 '22 at 17:34

list.remove() removes an item by value, not by index. So letters[0].remove('b') would work.
Simply deleting a single element with the same syntax, you could address it in any other statement is del which could be used as del letters[0][0]
As @Barmar said: list.pop) can return an element by index and remove it from the list.

score 0 · Answer 3 · answered Jul 25 '22 at 17:58

You can try this if you want to delete the element by index value of the list:

del letters[0][0]  # [['b', 'c'], ['a', 'b', 'c']]
del letters[1][0]  # [['a', 'b', 'c'], ['b', 'c']]

or if you want remove specific value in the first occurance:

letters[0].remove('a')  # [['b', 'c'], ['a', 'b', 'c']]
letters[1].remove('a')  # [['a', 'b', 'c'], ['b', 'c']]

3 Answers3