In this article, a List of sets is given our task is to write a program to perform their intersection using Python.
Examples of finding the intersection of multiple sets
Input : test_list = [{5, 3, 6, 7}, {1, 3, 5, 2}, {7, 3, 8, 5}, {8, 4, 5, 3}]
Output : {3, 5}
Explanation : 3 and 5 is present in all the sets.
Method 1: Using a Logical operator
This is the simplest method to get the intersection of multiple sets using the Python logical operator
Python3
set_1 = {21, 10, 5, 11, 12} set_2 = {5, 21, 3, 8, 9} set_3 = {1, 21, 5, 3, 4, 5} # getting all sets intersection using & operator set4 = set1 & set2 & set3 print(set4) |
Output:
{21, 5}
Method 2: Using intersection() + * operator
In this, we will perform tasks to get intersections using intersection() and the * operator is used to pack all the sets together.
Python3
# initializing list test_list = [{5, 3, 6, 7}, {1, 3, 5, 2}, {7, 3, 8, 5}, {8, 4, 5, 3}] # printing original list print("The original list is : " + str(test_list)) # getting all sets intersection using intersection() res = set.intersection(*test_list) # printing result print("Intersected Sets : " + str(res)) |
Output:
The original list is : [{3, 5, 6, 7}, {1, 2, 3, 5}, {8, 3, 5, 7}, {8, 3, 4, 5}]
Intersected Sets : {3, 5}
Method 3: Using reduce() + and_ operator
In this, we will perform intersection using and_ operator and Python reduce() does the task of getting all the sets packed together for the required operation.
Python3
from operator import and_ from functools import reduce # initializing list test_list = [{5, 3, 6, 7}, {1, 3, 5, 2}, {7, 3, 8, 5}, {8, 4, 5, 3}] # printing original list print("The original list is : " + str(test_list)) # getting all sets intersection using and_ operator res = set(reduce(and_, test_list)) # printing result print("Intersected Sets : " + str(res)) |
Output:
The original list is : [{3, 5, 6, 7}, {1, 2, 3, 5}, {8, 3, 5, 7}, {8, 3, 4, 5}]
Intersected Sets : {3, 5}
