Is there any problem to remove all 1's in python?

Question

data = [11,1,1,1,33,1,1,1,133,44,55]
for each in data:
    if each == 1:
        data.remove(1)
print(data)

OUTPUT:

[11, 33, 1, 1, 133, 44, 55]

Output should be `[11, 33, 133, 44, 55]`? – Toan Quoc Ho Oct 23 '19 at 07:56 — Toan Quoc Ho, Oct 23 '19 at 07:56

score 2 · Accepted Answer · answered Oct 23 '19 at 07:54

2

You should avoid modifying an iterable while iterating, since you're messing up the indexing.

Use list comprehensions to easily filter data:

[i for i in data if i!=1.]
# [11, 33, 133, 44, 55]

Or:

new_list = []
for each in data:
    if each != 1:
        new_list.append(each)

answered Oct 23 '19 at 07:54

yatu

It can be done without using new_list? – naga lokesh Oct 23 '19 at 11:55
I want to modify within the given list – naga lokesh Oct 23 '19 at 11:56
Then try removing the elements from the list asyou where doing, but from end to beginning, that way changes in the index don't affect @nagalokesh – yatu Oct 23 '19 at 11:58
data = [11,1,1,1,33,1,1,1,133,44,55] for each in data: if each == 1: data.remove(each) print(data) – naga lokesh Oct 23 '19 at 12:00
I tried but all 1's are not modified – naga lokesh Oct 23 '19 at 12:01
output: [11, 33, 1, 1, 133, 44, 55] – naga lokesh Oct 23 '19 at 12:02

1 Answers1