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In Python, lists allow the same element to appear multiple times. Even though the value of an element may be the same as other elements, each element will have a different index. Using these index numbers, you can easily access any element you want.

However, in some cases, you may not want multiple instances of the same element; then, you would definitely want to remove all those occurrences of that particular element from the list. In Python, there are different ways to achieve this.

filter()Use the function to remove all instances of an element from a list in Python

In Python, filter()filtering elements becomes easier with the help of functions. filter()Functions require two parameters, the first parameter is a function, and the second parameter can be a collection, list, tuple, etc.

Example 1: Function __ne__withfilter()

myList = [2, 1, 3, 5, 1, 1, 1, 0]
myList = list(filter((1).__ne__, myList))
print(myList)

Output:

[2, 3, 5, 0]

In this example, you have a list myListfrom which you want to remove all occurrences of 1. filter()The remove function takes another function __ne__that will return a boolean value of either or , depending on 1whether exists in the list . If the value exists in the list, then it will simply discard it. Then, whatever the remove function returns will be converted into a list using the remove function.myListTrueFalse1filter()list()

Example 2: Function with lambdafunctionfilter()

myList = [2, 1, 3, 5, 1, 1, 1, 0]
valueToBeRemoved = 1

result = filter(lambda val: val != valueToBeRemoved, myList)
print(list(result))

Output:

[2, 3, 5, 0]

__ne__Instead of passing a function, we pass a lambdafunction to filter()the function.

From the list myList, you will extract each element one by one and store it in valthe variable . If the elements present in valand valueToBeRemovedare not equal, only those valelements present in will be added to the new variable result. You should convert to a list using list()the function result.

Remove all instances of an element from a list using list comprehensions in Python

List comprehensions are a shorthand way to write code. List comprehensions are faster than regular functions and loops.

Sample code:

myList = [1, 2, 3, 4, 2, 2, 3]
valueToBeRemoved = 2

myList = [value for value in myList if value != valueToBeRemoved]

print(myList)

Output:

[1, 3, 4, 3]

You have a list myListfrom which you want to remove 2the occurrences of an element . The main code to remove all instances of an element is []inside the square brackets . Here, forthe loop will run first and then it will myListtake a value from the list and store it valuein the variable. After that, if valuethe value inside the variable and valueToBeRemovedthe variable do not match, it will simply return valuethe value of the variable and store it in the list myList. This process will continue until the list becomes empty. At the end, you will have a list with the output you wanted.

Use remove()the function to remove all instances of an element from Python

remove()The function removes only the first occurrence of an element. If you want to remove()remove all occurrences of an element using the function, you can use fora for loop or whilea for loop.

myList = [2, 1, 3, 5, 1, 1, 1, 0]
valueToBeRemoved = 1

try:
    while True:
        myList.remove(valueToBeRemoved)
except ValueError:
    pass

print(myList)

Output:

[2, 3, 5, 0]

In the code above, you create a list myListand then you have a variable valueToBeRemovedthat will contain the element you want to remove from the list, in this case 1. When looping through the list, if the element is in the list, it will be remove()removed from the list using the .