Python Set intersection() Method

The Set intersection() method finds the common elements between two or more sets. It returns a new set that contains only the items that exist in all the sets being compared.

Syntax

my_set.intersection(set1, set2, ...)

intersection() Parameters

Python Set intersection() method parameters:

intersection() Return Value

Python Set intersection() method returns a new set containing the common elements of all the sets being compared.

Examples

Example 1: Common Elements of Two Sets with intersection() method

A = {'Tom', 'Anna', 'David'}
B = {'David', 'Tom'}

result = A.intersection(B)

print(result) # Output: {'David', 'Tom'}

output

{'David', 'Tom'}

Example 2: Intersection between Multiple Sets

The intersection() method allows to compute the common elements 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.intersection(B, C)

print(result) # Output: {6, 7}

output

{6, 7}

Example 3: Intersection between a Set and a List

You can also pass iterables like list: intersection() first converts the iterables to sets and then computes the intersection.

For example:

A = {'a', 'e', 'i', 'o', 'u'}

B = ['d', 'e', 'f']

print(A.intersection(B)) # Output: {'e'}

output

{'e'}

Example 4: Intersection between a Set and a Tuple

You can also pass iterables like tuple: intersection() first converts the iterables to sets and then computes the intersection.

For example:

A = {'a', 'e', 'i', 'o', 'u'}

B = ('d', 'e', 'f')

print(A.intersection(B)) # Output: {'e'}

output

{'e'}

Example 5: Intersection between a Set and a Dictionary

You can also pass iterables like dictionary: intersection() first converts the iterables to sets and then computes the intersection.

For example:

A = {'a', 'e', 'i', 'o', 'u'}

B = {1: 'd', 2: 'e', 3: 'f'}
C = {'d': 1, 'e': 2, 'f': 3}

print(A.intersection(B)) # Output: set()
print(A.intersection(C)) # Output: {'e'}

output

set()
{'e'}

Example 6: Intersection between a Set and a String

You can also pass iterables like string: intersection() first converts the iterables to sets and then computes the intersection.

For example:

A = {'a', 'e', 'i', 'o', 'u'}

B = 'def'

print(A.intersection(B)) # Output: {'e'}

output

{'e'}

Equivalent Operator & for intersection()

Set intersection can be performed with the & operator as well, providing an alternative to the intersection() method.

A = {1, 2, 3, 4, 5}
B = {3, 4, 5, 6, 7}

print(A.intersection(B)) # Output: {3, 4, 5}

print(A & B) # Output: {3, 4, 5}

output

{3, 4, 5}
{3, 4, 5}

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}

print(A.intersection(B, C)) # Output: {6, 7}

print(A & B & C) # Output: {6, 7}

output

{6, 7}
{6, 7}