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Complete Guide to Removing Elements From Lists in Python

By Lane Wagner on Dec 9, 2021

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While lists aren’t the most efficient data structure if you’ll be doing lots of deleting from the middle, there are definitely good ways to accomplish the task. The built-in remove() method should be your first option. Let’s go over some examples.

๐Ÿ”— Remove element in Python list by value

primes = [2, 3, 5, 5, 7, 11]

primes.remove(5)

print(primes)
# [2, 3, 5, 7, 11]

primes.remove(5)
# [2, 3, 7, 11]

primes.remove(5)
# careful, this will throw an error
# ValueError: list.remove(x): x not in list

If you want to safely remove items, and you aren’t sure if they exist in the list or not, you can either catch the error:

try:
	primes.remove(5)
except Exception as e:
	print("not in list")

Or, you can check for existence first:

if 5 in primes:
	primes.remove(5)

๐Ÿ”— Remove an element in Python list by index

The del statement is a built-in keyword that allows you to remove items from lists. The simplest example deletes the item at a given index.

primes = [2, 3, 5, 5, 7, 11]

# delete the second item
del primes[1]

print(primes)
# [2, 5, 5, 7, 11]

Again, you need to be careful. If the index doesn’t exist an error will be raised.

primes = [2, 3, 5, 5, 7, 11]

# delete the eleventh item
del primes[10]

IndexError: list assignment index out of range

if len(primes) >= 10:
	del primes[10]

๐Ÿ”— Remove multiple of items from a python list

primes = [2, 3, 5, 5, 7, 11]

# deleting items from 2nd to 4th
del primes[1:4]

print(primes)
# [2, 7, 11]

๐Ÿ”— Remove item by index and return it

The .pop() method removes an item from a list by index and returns that item.

primes = [2, 3, 5, 7]

# pop the second element
popped = primes.pop(1)

print("popped:", popped)
# 3

print("list:", primes)
# [2, 5, 7]

If you don’t pass an index parameter to pop() it will default to -1 and remove the last element from the list. Just like the other methods, if you pass in a number too large, you’ll get the following error.

IndexError: pop index out of range

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