Python Matrix Multiplication

Here you will get program for python matrix multiplication.

If we want to multiple two matrices then it should satisfy one condition. We need to check this condition while implementing code without ignoring.

A_mxn x B_pxq then n should be equal to p. Then only we can multiply matrices. Now we will see how to multiply two matrices using python nested list matrix representation.

Python Matrix Multiplication

Below is python program to multiply two matrices.

def print_matrix(matrix):
        for i in range(len(matrix)):
                for j in range(len(matrix[0])):
                        print("\t",matrix[i][j],end=" ")
                print("\n")

def main():
        m = int( input("enter first matrix rows"));
        n = int( input("enter first matrix columns"));
        p = int( input("enter second matrix rows"));
        q = int( input("enter second matrix columns"));
        if( n != p):
                print ("matrice multipilication not possible...");
                exit();
        
#declaration of arrays
        array1=[[0 for j in range  (0 , n)] for i in range (0 , m)]
        array2=[[0 for j in range  (0 , q)] for i in range (0 , p)]
        result=[[0 for j in range  (0 , q)] for i in range (0 , m)]

#taking input from user
        print ("enter first matrix elements:" )
        for i in range(0 , m):
                for j in range(0 , n):
                        array1[i][j]=int (input("enter element"))
        print ("enter second matrix elements:")
        for i in range(0 , p):
                for j in range(0 , q):
                        array2[i][j]=int(input("enter element"))
        print ("first matrix")
        print_matrix(array1)
        print ("second matrix")
        print_matrix(array2)
        
#for multiplication
    # i will run throgh each row of matrix1
        for i in range(0 , m):
        # j will run through each column of matrix 2
                for j in range(0 , q):
                # k will run throguh each row of matrix 2
                        for k in range(0 , n):
                                result[i][j] += array1[i][k] * array2[k][j]
                                
                                
#printing result
        print ( "multiplication of two matrices:" )
        print_matrix(result)
        
main()

Output

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