Python | Cumulative Columns summation of Records

• Last Updated : 24 Aug, 2021

Sometimes, while working with records, we can have a problem in which we need to sum all the columns of a container of lists which are tuples. This kind of application is common in web development domain. Let’s discuss certain ways in which this task can be performed.
Method #1 : Using sum() + list comprehension + zip()
This task can be performed using combination of above functions. In this, we cumulate the like index elements, i.e columns using zip(), and then iterate through them using list comprehension and perform summation using sum().

Python3

 # Python3 code to demonstrate working of# Cumulative Columns summation of Records# using list comprehension + sum() + zip()  # initialize listtest_list = [(1, 2, 3), (6, 7, 6), (1, 6, 8)]  # printing original listprint("The original list : " + str(test_list))  # Cumulative Columns summation of Records# using list comprehension + sum() + zip()res =  [sum(ele) for ele in zip(*test_list)]  # printing resultprint("The Cumulative column sum is : " + str(res))
Output
The original list : [(1, 2, 3), (6, 7, 6), (1, 6, 8)]
The Cumulative column sum is : [8, 15, 17]

Method #2 : Using zip() + map() + sum()
This method is similar to the above method. In this, the task performed by list comprehension is performed by map(), which extends the summation of columns to zipped elements.

Python3

 # Python3 code to demonstrate working of# Cumulative Columns summation of Records# using zip() + map() + sum()  # initialize listtest_list = [(1, 2, 3), (6, 7, 6), (1, 6, 8)]  # printing original listprint("The original list : " + str(test_list))  # Cumulative Columns summation of Records# using zip() + map() + sum()res = list(map(sum, zip(*test_list)))  # printing resultprint("The Cumulative column sum is : " + str(res))
Output
The original list : [(1, 2, 3), (6, 7, 6), (1, 6, 8)]
The Cumulative column sum is : [8, 15, 17]

Attention geek! Strengthen your foundations with the Python Programming Foundation Course and learn the basics.

To begin with, your interview preparations Enhance your Data Structures concepts with the Python DS Course. And to begin with your Machine Learning Journey, join the Machine Learning - Basic Level Course

My Personal Notes arrow_drop_up