[python] How to trim a list in Python

Suppose I have a list with X elements

[4,76,2,8,6,4,3,7,2,1...]

I'd like the first 5 elements. Unless it has less than 5 elements.

[4,76,2,8,6]

How to do that?

This question is related to python list

The answer is


To trim a list in place without creating copies of it, use del:

>>> t = [1, 2, 3, 4, 5]
>>> # delete elements starting from index 4 to the end
>>> del t[4:]
>>> t
[1, 2, 3, 4]
>>> # delete elements starting from index 5 to the end
>>> # but the list has only 4 elements -- no error
>>> del t[5:]
>>> t
[1, 2, 3, 4]
>>> 

l = [4,76,2,8,6,4,3,7,2,1]
l = l[:5]

>>> [1,2,3,4,5,6,7,8,9][:5]
[1, 2, 3, 4, 5]
>>> [1,2,3][:5]
[1, 2, 3]