Remove all the occurrences of an element from a list in Python - GeeksforGeeks

09 Apr, 2022
The task is to perform the operation of removing all the occurrences of a given item/element present in a list. Examples :
Input : 1 1 2 3 4 5 1 2 1 Output : 2 3 4 5 2 Explanation : The input list is [1, 1, 2, 3, 4, 5, 1, 2] and the item to be removed is 1. After removing the item, the output list is [2, 3, 4, 5, 2] Input : 5 6 7 8 9 10 7 Output : 5 6 8 9 10
In this article, we shall see how to execute this task in 3 ways :
Using list comprehensionUsing filter() and __ne__Using remove()
Using list comprehension
Using filter() and __ne__
Using remove()
Method 1 : Using list comprehension The list comprehension can be used to perform this task in which we just check for a match and reconstruct the list without the target element. We can create a sublist of those elements in the list that satisfies a certain condition. 
Python3
# Python 3 code to demonstrate# the removal of all occurrences of a# given item using list comprehension def remove_items(test_list, item):         # using list comprehension to perform the task    res = [i for i in test_list if i != item]     return res # driver codeif __name__=="__main__":         # initializing the list    test_list = [1, 3, 4, 6, 5, 1]     # the item which is to be removed    item = 1     # printing the original list    print ("The original list is : " + str(test_list))     # calling the function remove_items()    res = remove_items(test_list, item)     # printing result    print ("The list after performing the remove operation is : " + str(res))
Output
The original list is : [1, 3, 4, 6, 5, 1]
The list after performing the remove operation is : [3, 4, 6, 5]
Method 2 : Using filter() and __ne__ We filter those items of the list which are not equal __ne__ to the item. 
Python3
# Python 3 code to demonstrate# the removal of all occurrences of# a given item using filter() and __ne__ def remove_items(test_list, item):         # using filter() + __ne__ to perform the task    res = list(filter((item).__ne__, test_list))     return res # driver codeif __name__=="__main__":         # initializing the list    test_list = [1, 3, 4, 6, 5, 1]     # the item which is to be removed    item = 1     # printing the original list    print ("The original list is : " + str(test_list))     # calling the function remove_items()    res = remove_items(test_list, item)     # printing result    print ("The list after performing the remove operation is : " + str(res))
Output
The original list is : [1, 3, 4, 6, 5, 1]
The list after performing the remove operation is : [3, 4, 6, 5]
Method 3 : Using remove() In this method, we iterate through each item in the list, and when we find a match for the item to be removed, we will call remove() function on the list. 
Python3
# Python 3 code to demonstrate# the removal of all occurrences of# a given item using remove() def remove_items(test_list, item):         # remove the item for all its occurrences    c = test_list.count(item)    for i in range(c):            test_list.remove(item)     return test_list # driver codeif __name__=="__main__":         # initializing the list    test_list = [1, 3, 4, 6, 5, 1]     # the item which is to be removed    item = 1     # printing the original list    print ("The original list is :" + str(test_list))     # calling the function remove_items()    res = remove_items(test_list, item)     # printing result    print ("The list after performing the remove operation is :" + str(res))
Output
The original list is : [1, 3, 4, 6, 5, 1]
The list after performing the remove operation is : [3, 4, 6, 5]
saumya1126
Python list-programs
python-list
Python
python-list
Writing code in comment?
Please use ide.geeksforgeeks.org,
generate link and share the link here.
How to Install PIP on Windows ?
Check if element exists in list in Python
How To Convert Python Dictionary To JSON?
Python Classes and Objects
How to drop one or multiple columns in Pandas Dataframe
Defaultdict in Python
Python | Get unique values from a list
Python | os.path.join() method
Create a directory in Python
Python | Pandas dataframe.groupby()