Remove First Element from a List in Python

To remove the first element from a list in Python, you can use any of the following methods:

(1) Using del

The del statement in Python is used to remove objects. You can also use it to remove the first element from a list.

For example:

my_list = [5, 10, 15, 20]

del my_list[0]
print(my_list) # Output: [10, 15, 20]

The indices in Python start at the position 0. Therefore, del my_list[0] removes the first element of the list.

The del statement is the most efficient method to remove the first item from a list. This method modifies the original list.

(2) Using pop()

The pop() method removes and returns the specified item from the list.

To remove the first item from a list using pop(), you can specify the index as 0. This method modifies the original list.

For example:

my_list = [5, 10, 15, 20]

removed_item = my_list.pop(0)
print(my_list) # Output: [10, 15, 20]
print(removed_item) # Output: 5

If you do not specify the index, the pop() method removes and returns the last element of the list.

(3) Using slicing

Slicing extracts portions (slices) of a list by specifying a range of indices.

To remove the first item from a list in Python using slicing, you can create a new list that exclude the first item.

For example:

my_list = [5, 10, 15, 20]

new_list = my_list[1:]
print(new_list) # Output: [10, 15, 20]

In the above example, the slice my_list[1:] starts at index 1 because Python uses 0-based indexing, where the first element is at the index 0. The start index 1 means the slice begins at the second element (10). The end index is omitted, so the slice includes all elements from the index 1 to the end of the list.

This method doesn’t modify the original list.

Choosing the right method

Use del if you don’t need to keep the removed element. This is the most efficient method in terms of performance.

Use pop() if you need to remove and retrieve the first element for further use.

Use slicing if you need to preserve the original list. This is the slowest method to remove the first item from a list.