Python Set difference() Function
The Set difference() method finds the difference between two sets. It returns a new set that contains all the elements of the first set that are not present in the second set.
Syntax
my_set.difference(set1, set2, ...)
difference() Parameters
Python Set difference() function parameters:
| Parameter | Condition | Description |
|---|---|---|
set1, set2, ... | Optional | A comma-separated list of one or more sets to find differences in |
You can also pass iterables like list, tuple, dictionary or string. In that case, difference() method first converts the iterables into sets and then computes the difference.
difference() Return Value
Python Set difference() function returns a set with elements unique to the first set.
Examples
Example 1: Difference between Two Sets
A = {'Tom', 'Anna', 'David'}
B = {'David', 'Tom'}
result = A.difference(B)
print(result) # Output: {'Anna'}
output
{'Anna'}
Example 2: Difference between Multiple Sets
The difference() method allows to compute the difference between multiple sets:
A = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10}
B = {3, 4, 5, 6, 7}
C = {6, 7, 8, 9, 10}
result = A.difference(B, C)
print(result) # Output: {1, 2}
output
{1, 2}
Example 3: Difference between a Set and a List
You can also pass iterables like list: difference() first converts the iterables to sets and then computes the difference.
For example:
# create a Set A
A = {'a', 'e', 'i', 'o', 'u'}
# create a List B
B = ['d', 'e', 'f']
result = A.difference(B)
print(result) # Output: {'i', 'a', 'o', 'u'}
output
{'i', 'a', 'o', 'u'}
Example 4: Difference between a Set and a Tuple
You can also pass iterables like tuple: difference() first converts the iterables to sets and then computes the difference.
For example:
# create a Set A
A = {'a', 'e', 'i', 'o', 'u'}
# create a Tuple B
B = ('d', 'e', 'f')
result = A.difference(B)
print(result) # Output: {'i', 'a', 'o', 'u'}
output
{'i', 'a', 'o', 'u'}
Example 5: Difference between a Set and a Dictionary
You can also pass iterables like dictionary: difference() first converts the iterables to sets and then computes the difference.
The dictionary keys are used for difference(), not the values!
For example:
# create a Set A
A = {'a', 'e', 'i', 'o', 'u'}
# create Dictionary B and C
B = {1: 'd', 2: 'e', 3: 'f'}
C = {'d': 1, 'e': 2, 'f': 3}
print(A.difference(B)) # Output: {'o', 'e', 'i', 'a', 'u'}
print(A.difference(C)) # Output: {'o', 'a', 'u', 'i'}
output
{'o', 'e', 'i', 'a', 'u'}
{'o', 'a', 'u', 'i'}
Example 6: Difference between a Set and a String
You can also pass iterables like string: difference() first converts the iterables to sets and then computes the difference.
For example:
# create a Set A
A = {'a', 'e', 'i', 'o', 'u'}
# create a String B
B = 'def'
print(A.difference(B)) # Output: {'i', 'a', 'o', 'u'}
output
{'i', 'a', 'o', 'u'}
Equivalent Operator – for difference()
Set difference can be performed with the - operator as well, providing an alternative to the difference() method.
A = {1, 2, 3, 4, 5}
B = {3, 4, 5, 6, 7}
# by difference() method
print(A.difference(B)) # Output: {1, 2}
# by - operator
print(A - B) # Output: {1, 2}
output
{1, 2}
{1, 2}
Of course, you can use the - operator with multiple sets:
A = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10}
B = {3, 4, 5, 6, 7}
C = {6, 7, 8, 9, 10}
# by difference() method
print(A.difference(B, C)) # Output: {1, 2}
# by - operator
print(A - B - C) # Output: {1, 2}
output
{1, 2}
{1, 2}