Python – Summation in Dual element Records List

Sometimes, while working with Records list, we can have problem in which we perform the summation of dual tuple records and store it in list. This kind of application can occur over various domains. Lets discuss certain ways in which this task can be performed. 

Method #1 : Using list comprehension This is one of the way to solve this problem. In this we perform summation of dual tuples in a list and iteration is performed inside comprehended list. 

Python3

# Python3 code to demonstrate
# Summation in Dual element Records List
# using list comprehension

# Initializing list
test_list = [(6, 7), (2, 4), (8, 9), (6, 2)]

# printing original lists
print("The original list is : " + str(test_list))

# Summation in Dual element Records List
# using list comprehension
res = [ele[0] + ele[1] for ele in test_list]

# printing result
print ("Summation pairs in tuple list : " + str(res))

Output : 

The original list is : [(6, 7), (2, 4), (8, 9), (6, 2)]
Summation pairs in tuple list : [13, 6, 17, 8]

Time complexity: O(n), where n is the number of elements in the input list “test_list”.
Auxiliary space: O(n), where n is the number of elements in the input list “test_list”. This is because a new list of size n is created to store the result of the summation.

Method #2 : Using reduce() + add() This is yet another way to perform this task. In this, we iterate through the list and perform summation using reduce() and add() respectively. 

Python3

# Python3 code to demonstrate
# Summation in Dual element Records List
# using reduce() + add()
from operator import add
from functools import reduce

# Initializing list
test_list = [(6, 7), (2, 4), (8, 9), (6, 2)]

# printing original lists
print("The original list is : " + str(test_list))

# Summation in Dual element Records List
# using reduce() + add()
res = [reduce(add, sub, 0) for sub in test_list]

# printing result
print ("Summation pairs in tuple list : " + str(res))

Output : 

The original list is : [(6, 7), (2, 4), (8, 9), (6, 2)]
Summation pairs in tuple list : [13, 6, 17, 8]

Time complexity: O(n), where n is the number of elements in the input list test_list. This is because the reduce() function takes O(n) time to process the elements in each tuple, and the for loop takes O(n) time to process all n tuples in test_list.
Auxiliary space: O(n), where n is the number of elements in the input list test_list. This is because the res list, which contains the sums of each tuple in test_list, takes up O(n) space.

Method #3 : Using sum(),list() methods

Python3

# Python3 code to demonstrate
# Summation in Dual element Records List

# Initializing list
test_list = [(6, 7), (2, 4), (8, 9), (6, 2)]

# printing original lists
print("The original list is : " + str(test_list))

# Summation in Dual element Records List
res=[]
for i in test_list:
    res.append(sum(list(i)))

# printing result
print ("Summation pairs in tuple list : " + str(res))

Output

The original list is : [(6, 7), (2, 4), (8, 9), (6, 2)]
Summation pairs in tuple list : [13, 6, 17, 8]