Python Program To Add Two MxN Matrices

The addition is one of the most basic operations that we perform on two or more matrices. The only condition to add or subtract two matrices is that both should have the same dimensions which means both matrices should have the same number of rows and columns.

Now to add two matrices just add the corresponding entries and place the sum at the corresponding position in the resultant matrix.

Suppose A = [a_ij]_mxn and B = [b_ij]_mxn are two matrices of order m x n, then the addition of A and B is given by;

A + B = [a_ij]_mxn + [b_ij]_mxn = [a_ij + b_ij]_mxn

In this article, you will see the python code to add two matrices.

Python program for addition of two matrices

There are multiple ways in which you can perform the same task using programming. The two most common methods to add matrices in Python are given below.

Using nested for loop
Using list comprehension

Using nested for loop

Here we will iterate through all the elements of both matrices by using nested for loop one by one, adding them, and storing each element at their corresponding positions in a third matrix.

# Python program to add two matrices using nested for loops

matrix1 = [[1,0,-1],
	  [3 ,8,6],
          [6 ,9,2]]

matrix2 = [[0,2,4],
	  [7,-9,3],
	  [4,0,1]]


matrix_sum = [[0,0,0],
              [0,0,0],
             [0,0,0]]

# Iterate through matrix rows
for i in range(len(matrix1)):
# Iterate through matrix columns
	for j in range(len(matrix1[0])):
# Addition of matrix elements
		matrix_sum[i][j] = matrix1[i][j] + matrix2[i][j]

for r in matrix_sum:
	print(r)
print("\n")

Save this file with the .py extension and then run this program you will see the given output :

Using list comprehension

This method provides a shorter way to do the same task. Here we will use list comprehension to add two matrices.

# Python program to add two matrices using list comprehension

matrix1 = [[1,8,3],
          [0 ,-5,7],
          [7 ,0,5]]

matrix2 = [[0,6,1],
          [6,9,0],
          [1,2,9]]
# Addition of matrix elements
matrix_sum = [[matrix1[i][j] + matrix2[i][j]  for j in range(len(matrix1[0]))] for i in range(len(matrix1))]

for r in matrix_sum:
   print(r)

You will see the given output in your terminal –