Given multiple sets list, the task is to write a Python program to find union of each set.
Examples:
Input : test_list = [{4, 3, 5, 2}, {8, 4, 7, 2}, {1, 2, 3, 4}, {9, 5, 3, 7}]
Output : {1, 2, 3, 4, 5, 7, 8, 9}
Explanation : All elements from all sets included. Duplicates removed.
Input : test_list = [{4, 3, 5, 2}, {8, 4, 7, 2}, {1, 2, 3, 4}]
Output : {1, 2, 3, 4, 5, 7, 8}
Explanation : All elements from all sets included. Duplicates removed.
Method #1 : Using union() + * operator
In this, we perform task of getting union using union(), and * operator is used to perform task of packing all the sets together.
Python3
# Python3 code to demonstrate working of # Union multiple sets # Using union() + * operator # initializing list test_list = [{ 4 , 3 , 5 , 2 }, { 8 , 4 , 7 , 2 }, { 1 , 2 , 3 , 4 }, { 9 , 5 , 3 , 7 }] # printing original list print ( "The original list is : " + str (test_list)) # * operator packs sets for union res = set ().union( * test_list) # printing result print ( "Multiple set union : " + str (res)) |
Output:
The original list is : [{2, 3, 4, 5}, {8, 2, 4, 7}, {1, 2, 3, 4}, {9, 3, 5, 7}]
Multiple set union : {1, 2, 3, 4, 5, 7, 8, 9}
Method #2 : Using chain.from_iterable() + * operator
In this, we perform task of union, which in turn is flattening using from_iterable().
Python3
# Python3 code to demonstrate working of # Union multiple sets # Using chain.from_iterable() + * operator from itertools import chain # initializing list test_list = [{ 4 , 3 , 5 , 2 }, { 8 , 4 , 7 , 2 }, { 1 , 2 , 3 , 4 }, { 9 , 5 , 3 , 7 }] # printing original list print ( "The original list is : " + str (test_list)) # * operator packs sets for union res = set (chain( * test_list)) # printing result print ( "Multiple set union : " + str (res)) |
Output:
The original list is : [{2, 3, 4, 5}, {8, 2, 4, 7}, {1, 2, 3, 4}, {9, 3, 5, 7}]
Multiple set union : {1, 2, 3, 4, 5, 7, 8, 9}
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