Python program multiplication of two matrix.

Given two user input matrix. Our task is to display the addition of two matrix. In these problem we use nested List comprehensive.

Algorithm

Step1: input two matrix.
Step 2: nested for loops to iterate through each row and each column.
Step 3: take one resultant matrix which is initially contains all 0. Then we multiply each row elements of first matrix with each elements of second matrix, then add all multiplied value. That is the value of resultant matrix.

Example Code

# Program to multiply two matrices
A=[]
n=int(input("Enter N for N x N matrix: "))         
print("Enter the element ::>")
for i in range(n): 
   row=[]                                      #temporary list to store the row
   for j in range(n): 
      row.append(int(input()))           #add the input to row list
      A.append(row)                      #add the row to the list
print(A)
# [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
#Display the 2D array
print("Display Array In Matrix Form")
for i in range(n):
   for j in range(n):
      print(A[i][j], end=" ")
   print()                                        #new line
B=[]
n=int(input("Enter N for N x N matrix : "))           #3 here
#use list for storing 2D array
#get the user input and store it in list (here IN : 1 to 9)
print("Enter the element ::>")
for i in range (n): 
   row=[]                                      #temporary list to store the row
   for j in range(n): 
      row.append(int(input()))           #add the input to row list
      B.append(row)                       #add the row to the list
print(B)
# [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
#Display the 2D array
print("Display Array In Matrix Form")
for i in range(n):
   for j in range(n):
      print(B[i][j], end=" ")
   print()                                           
result = [[0,0,0], [0,0,0], [0,0,0]] 
for i in range(len(A)): 
   for j in range(len(B[0])): 
      for k in range(len(B)): 
         result[i][j] += A[i][k] * B[k][j] 
print("The Resultant Matrix Is ::>")
for r in result: 
   print(r) 

Output

Enter N for N x N matrix: 3
Enter the element ::>
2
1
4
2
1
2
3
4
3
[[2, 1, 4], [2, 1, 2], [3, 4, 3]]
Display Array In Matrix Form
2 1 4 
2 1 2 
3 4 3 
Enter N for N x N matrix : 3
Enter the element ::>
1
2
3
4
5
6
7
8
9
[[1, 2, 3], [4, 5, 6], [7, 8, 9]]
Display Array In Matrix Form
1 2 3 
4 5 6 
7 8 9 
The Resultant Matrix Is ::>
[34, 41, 48]
[20, 25, 30]
[40, 50, 60]