Python | Get sum of tuples having same first value
Given a list of tuple, the task is to sum the tuples having same first value.
Examples:
Input: [(1, 13), (2, 190), (3, 82), (1, 12)] Output: [(1, 25), (2, 190), (3, 82)] Input: [(1, 13), (1, 190), (3, 25), (1, 12)] Output: [(1, 215), (3, 25)]
Let’s discuss the different ways we can do this task.
Method #1: Using map()
# Python code to get sum of tuples having same first value # Initialisation of list of tuple Input = [( 1 , 13 ), ( 1 , 190 ), ( 3 , 25 ), ( 1 , 12 )] d = {x: 0 for x, _ in Input } for name, num in Input : d[name] + = num # using map Output = list ( map ( tuple , d.items())) # printing output print (Output) |
Output:
[(1, 215), (3, 25)]
Method #2: Using defaultdict
# Python code to sum list of tuples having same first value # Importing from collections import defaultdict # Initialisation of list of tuple Input = [( 2 , 190 ), ( 1 , 13 ), ( 1 , 12 ), ( 2 , 14 ), ( 3 , 82 ), ( 1 , 70 )] # Initialisation of defaultdict output = defaultdict( int ) for k, v in Input : output[k] + = v # Printing output print ( list (output.items())) |
Output:
[(1, 95), (2, 204), (3, 82)]
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