Python Program to Multiply Two Matrices Using Multi-dimensional Arrays

In this python tutorial, you will learn how to Multiply Two Matrices Using Multi-dimensional Arrays with for loop of the python programming language.

How to Multiply Two Matrices Using Multi-dimensional Arrays?

Let’s take a look at the source code,  here the values are assigned in the code, the for loop carry out the function.

# Python Program to Multiply Two Matrices Using Multi-dimensional Arrays

X = [[12,7,3],
    [4 ,5,6],
    [7 ,8,9]]

Y = [[5,8,1,2],
    [6,7,3,0],
    [4,5,9,1]]

result = [[0,0,0,0],
         [0,0,0,0],
         [0,0,0,0]]

for i in range(len(X)):
   
   for j in range(len(Y[0])):
      
       for k in range(len(Y)):
           result[i][j] += X[i][k] * Y[k][j]

for r in result:
   print(r)

OUTPUT:

[114, 160, 60, 27]
[74, 97, 73, 14]
[119, 157, 112, 23]

1. At first, we enter the values of three matrices. The first one with 3 rows and 3 columns and assign that matrix to the variable X. The second one with 3 rows and 4 columns and assign that matrix to the variable  Y.
2. The third one with 3 rows and 4 columns, which is a null matrix and assign that matrix to the variable  result. The values are enclosed within square brackets and closed on the whole with the same.
3.  We declare a for loop where the range for the variable i is (len(X)) after which we declare another for loop where the range for the variable j is (len(Y[0]))
4. We declare a for loop where the range for the variable k is (len(Y)) for which we give the condition [i][j] += X[i][k] * Y[k][j]
5. We declare the final for loop where the result is the variable r after which we give a print function which will display the values stored in the variable r
6. In the above code we have used the for loops to iterate through each row and each column. We get the sum of products in the result.

NOTE:

• The print function is used to display the value, it prints the specified message to the screen
•  The For loops are used to loop through an iterable object and perform the same action for each entry.
• The len() is a built function  used to calculate the length of any iterable object
• The Addition assignment operator ( += ) adds the value of the right operand to a variable and assigns the result to the variable.