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To remove multiple values ​​from a Python list, we can either remove the actual values ​​of the list or the index of the values ​​to be removed from the list. We can use if...elsecontrol statements, list comprehensions, list slicing, and forloops to remove multiple elements from a list in Python.

Use if...elsethe control statement to remove multiple elements from a list

We can use if...elsecontrol statements to remove multiple values ​​from a list in Python if the values ​​meet a certain condition. We can also remove an element if its index meets a certain condition.

list1 = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20]
print("Original list : ", list1)


for ele in list1:
    if (ele % 2) != 0:
        list1.remove(ele)

print("List after deleting all values which are odd : ", list1)

Output:

Original list :  [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20]
List after removing all the odd values :  [2, 4, 6, 8, 10, 20]

Here, we have a list of integers and we need to remove the elements having odd values ​​from the list. In this case, we loop through all the list l1elements and if the element has an odd value, then we remove()remove that element from the list using the remove method.

Remove multiple elements from a list using list comprehension in Python

In Python, list comprehension refers to the process of generating a new list from an existing list. List comprehensions can also be used to remove multiple elements from a list. We can create a new list by removing the values ​​to be removed from the original list.

l1 = [2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 80, 99]
l2 = [x for x in l1 if x % 2 == 0]

print("Original list : ", l1)
print("List after deleting all the odd values present in List : ", l2)

Output:

Original List :  [2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 80, 99]
List after deleting all the odd values present in List :  [2, 4, 6, 8, 10, 20, 80]

Here, we l1create a list from the list l2that contains only l1all the even values ​​in . In other words, we can say that we created a new list l1from the existing list by removing all the odd values ​​in the list .l1l2

Remove multiple elements from a list using list slicing

We can also remove multiple elements from a list using List slice method. Here, we can delput the range of elements from the start index to the last index of the elements that you want to remove from the list in the method.

Instead of using a single index in the remove() method, we deluse a range of values ​​from the start to the last index of the element to be removed from the list. It will remove consecutive elements from the list. We have to note that for lists, the indexing of values ​​in Python starts from 0.

l1 = [2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 80, 99]
print("Original list : ", l1)

del l1[2:5]

print("List after removing values at index 2, 3 and 4 : ", l1)

Output:

Original List :  [2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 80, 99]
List after removing values at index 2, 3 and 4 :  [1, 2, 6, 7, 8, 9, 10, 20, 80, 99]

It uses delthe method l1to remove the values ​​at index 2, 3and from the list 4.
An important thing to note here is that the first index 2is inclusive, i.e. the element at 3index in the list is removed, whereas the last index is exclusive, which means the element at 2index in the list is not removed.56

Use forloop to remove multiple elements from a list

We can also use fora loop to remove multiple elements from a list.
To apply this method, we have to store the index of the elements to be removed from the list. But random removal of elements will result in changing the value of the index. Our smart strategy is to remove the elements which have a greater position in the list. So the values ​​of elements at other indexes will not change. Now, we will sort the list in descending order to remove the elements with higher index first. The code for this approach is shown below.

l1 = [2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 80, 99]
print("Original list : ", l1)

indexes_to_be_removed = [0, 2, 5]

for idx in sorted(indexes_to_be_removed, reverse=True):
    del l1[idx]

print("List after removing values at index 0, 2 and 5: ", l1)

Output:

Original List :  [2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 80, 99]
List after removing values at index 0, 2 and 5:  [3, 5, 6, 8, 9, 10, 20, 80, 99]

It uses delthe method l1to remove the values ​​at indexes 0, 2, and from the list 5.