Python Set intersection() Method

The set.intersection() method returns a new set with the elements that are common in the given sets.

Syntax:

set.intersection(*other_sets)

Parameters:

other_sets: Optional. A comma separates one or more sets. Returns the shallow copy of a set if no parameter is passed.

Return Value:

A set with common elements among all sets.

The following example demonstrates the set.intersection() method.

Example:
nums = {1, 2, 3, 4, 5 }
oddNums = {1, 3, 5, 7, 9}
commonNums = nums.intersection(oddNums)
print("Common elements in nums and oddNums are: ", commonNums)

numscopy = nums.intersection() # returns shallow copy if no argument passed
print("Shallow copy: ", numscopy)
Output
Common elements in nums and oddNums are:  {1, 3, 5}
Shallow copy: {1, 2, 3, 4, 5 }

The set.intersection() method can work on multiple sets too.

Example:
nums = {1, 2, 3, 4, 5}
oddNums = {1, 3, 5, 6, 7, 9}
primeNums = {2, 3, 5, 7}
commonNums = nums.intersection(oddNums, primeNums)
print("Common elements: ", commonNums)
Output
Common elements: {3, 5}

The & operator can also be used to find the intersection of sets.

Example:
nums = {1,2,3,4,5,6,7,8,9,10}
oddNums = {1,3,5,6,7,9}
primeNums = {2,3,5,7}
commonNums = Nums & oddNums & primeNums

print("Common elements: ", commonNums)
Output
Common elements: {3, 5}

It returns an empty set if no common elements are found.

Example:
nums = {10, 20, 30, 40}
oddNums = {1, 3, 5, 6, 7, 9}
commonNums = nums & oddNums
print("Common elements: ", commonNums)

commonNums = nums.intersection(oddNums)
print("Common elements: ", commonNums)
Output
Common elements: set()
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