Python – Get Matrix Mean
Given a Matrix, Find its mean.
Input : test_list = [[5, 6, 7], [7, 5, 6]]
Output : 6.0
Explanation : 36 / 6 = 6.0Attention 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
Input : test_list = [[5, 6, 7, 4, 8]]
Output : 6.0
Explanation : 30 / 5 = 6.0
Method #1 : Using list comprehension + sum() + len() + zip()
The combination of above functions can be used to solve this problem. In this, we perform the mean calculation using sum() and len(), zip() along with * operator does task of extracting each element of rows of matrix.
Python3
# Python3 code to demonstrate working of # Matrix Mean# Using list comprehension + sum() + len() + zip() # initializing liststest_list = [[5, 6, 3], [8, 3, 1], [9, 10, 4], [8, 4, 2]] # printing original listprint("The original list : " + str(test_list)) # zip() to get all elements # sum() / len() gives mean# extracts column meanres = [sum(idx) / len(idx) for idx in zip(*test_list)] # extracts all elements meanres = sum(res) / len(res) # printing result print("Matrix Mean : " + str(res)) |
The original list : [[5, 6, 3], [8, 3, 1], [9, 10, 4], [8, 4, 2]] Matrix Mean : 5.25
Method #2 : Using mean() + zip() + list comprehension
This is another method in which this task can be performed. In this, we extract mean using inbuilt method of mean() .
Python3
# Python3 code to demonstrate working of # Matrix Mean# Using mean() + zip() + list comprehensionfrom statistics import mean # initializing liststest_list = [[5, 6, 3], [8, 3, 1], [9, 10, 4], [8, 4, 2]] # printing original listprint("The original list : " + str(test_list)) # zip() to get all elements # mean() gives mean# extracts column meanres = [mean(idx) for idx in zip(*test_list)] # extracts all elements meanres = mean(res) # printing result print("Matrix Mean : " + str(res)) |
The original list : [[5, 6, 3], [8, 3, 1], [9, 10, 4], [8, 4, 2]] Matrix Mean : 5.25
