Python Set discard() Function

Python discard() is a built-in method to remove elements from the set. The discard() method takes exactly one argument. This method does not return any value.

Example: In this example, we are removing the integer 3 from the set with discard() in Python.

Python3

my_set = {1, 2, 3, 4, 5}
my_set.discard(3)
print(my_set)

Output

{1,2,4,5}

Python Set discard() Syntax

set.discard(element)

Parameter
element – an item to remove from the set.

Return Value
return  – discard() method doesn’t return any value.

Python Set discard() Examples

Discard() an item from a set that is present in the Python Set

In this example, we have a set and we use discard() to remove an existing integer “5” from the set using Python.

Python3

numbers = {1, 2, 3, 4, 5, 6, 7, 8, 9}

print(numbers)

# Deleting 5 from the set
numbers.discard(5)

# printing the resultant set
print(numbers)

Output

{1, 2, 3, 4, 5, 6, 7, 8, 9}
{1, 2, 3, 4, 6, 7, 8, 9}

Discard() an item from a set that is not present in the Python set

In this example, we have a set and we use discard() to remove a non-existing integer “13” from the set using Python.

Python3

numbers = {1, 2, 3, 4, 5, 6, 7, 8, 9}

print(numbers)

# passing an element that is not in set
numbers.discard(13)
# this will not throw any errors but set remains
# same as before

# printing the resultant set
print("\nresultant set : ", numbers)

Output

{1, 2, 3, 4, 5, 6, 7, 8, 9}
resultant set :  {1, 2, 3, 4, 5, 6, 7, 8, 9}

Discard() a String item from a set that is present in the Python Set

In this example, we have a set and we use discard() to remove an existing string “geek” from the set using Python.

Python3

myset = {'a', 1, "geek", 2, 'b', 'abc', "geeksforgeeks", 8}

print(myset)

# Deleting a from the set
myset.discard("geek")

# printing the resultant set
print(myset)

Output

{1, 2, 'b', 'a', 8, 'geeksforgeeks', 'abc', 'geek'}
{1, 2, 'b', 'a', 8, 'geeksforgeeks', 'abc'}

Discard() String item from a set that is not present in the Python Set

In this example, we have a set and we use discard() to remove a non-existing string “geeks” from the set using Python.

Python3

myset = {'a', 1, "geek", 2, 'b', 'abc', "geeksforgeeks", 8}

print(myset)

# trying to Delete geeksfrom the set which is not there
myset.discard("geeks")

# printing the resultant set
print(myset)

Output

{1, 2, 'b', 'a', 8, 'geeksforgeeks', 'abc', 'geek'}
{1, 2, 'b', 'a', 8, 'geeksforgeeks', 'abc', 'geek'}

Note – To know the difference between discard() and remove() click here.