Different ways to clear a list in Python

In this article, we will explore various methods to clear a list in Python. The simplest way to do is by using a loop.

Using clear() Method

Using clear() method we can remove all elements from a list. This method modifies the list in place and removes all its elements.

a = [1, 2, 3, 4, 5]
a.clear()
print("List after clearing:", a)

List after clearing: []

Explaination: a.clear() clears all elements of the list a.

Note: This method modify the original list in-place.

Let's explore other different ways to clear a list in Python:

Reassigning to an Empty List

Another common method to clear a list is by simply reassigning the list to an empty list []. This method also clears the list but it does not modify the original list in place.

a = [1, 2, 3, 4, 5]

# Reassign 'a' to a new empty list
a = []

# Print the current state of 'a'
print("List after reassignment:", a)

List after reassignment: []

Explaination:

• Reassigning a = [] creates a new empty list and assigns it to the variable a.
• The original list is not affected and the reference to the old list is lost.

Using del Statement

The del statement can be used to delete all items in a list. This method removes the items from the list and the list is modified in place.

a = [1, 2, 3, 4, 5]
del a[:]
print("List after using del:", a)

List after using del: []

Explaination:

• del a[:] deletes all elements from the list a.
• This modifies the list in place and leaves it empty.

Using a Loop with pop()

We can use pop() method in a loop to remove elements from the list one by one. Although this is not the most efficient method.

Example:

while a:
a.pop()