Remove element in list using list comprehension - Python

Question

I have a list like this:

['A','B','C']

What I need is to remove one element based on the input I got in the function. For example, if I decide to remove A it should return:

['B','C']

I tried with no success

list = ['A','B','C']
[var for var in list if list[var] != 'A']

How can I do it? Thanks

Answer 1

The improvement to your code (which is almost correct) would be:

list = ['A','B','C']
[var for var in list if var != 'A']

However, @frostnational's approach is better for single values.

If you are going to have a list of values to disallow, you can do that as:

list = ['A','B','C', 'D']
not_allowed = ['A', 'B']
[var for var in list if var not in not_allowed]

Answer 2

Simple lst.remove('A') will work:

>>> lst = ['A','B','C']
>>> lst.remove('A')
['B', 'C']

However, one call to .remove only removes the first occurrence of 'A' in a list. To remove all 'A' values you can use a loop:

for x in range(lst.count('A')):
    lst.remove('A')

If you insist on using list comprehension you can use

>>> [x for x in lst if x != 'A']
['B', 'C']

The above will remove all elements equal to 'A'.