How to multiply two matrices with python

Configurare noua (How To)

Situatie

How to create a program to multiply two matrices in python.
Examples:

Input : X = [[1, 7, 3],
             [3, 5, 6],
             [6, 8, 9]]
       Y = [[1, 1, 1, 2],
           [6, 7, 3, 0],
           [4, 5, 9, 1]]
 
Output : [55, 65, 49, 5]
         [57, 68, 72, 12]
         [90, 107, 111, 21]

Backup

# take a 3x3 matrix
A = [[12, 7, 3],
    [4, 5, 6],
    [7, 8, 9]]
# take a 3x4 matrix   
B = [[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]]
# iterating by row of A
for i in range(len(A)):
    # iterating by column by B
    for j in range(len(B[0])):
        # iterating by rows of B
        for k in range(len(B)):
            result[i][j] += A[i][k] * B[k][j]
for r in result:
    print(r)
Output:
[114, 160, 60, 27]
[74, 97, 73, 14]
[119, 157, 112, 23]

Solutie

Tip solutie

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