Как написать программу умножение матрицы на число без numpy

Question

Моя попытка

def multiply_matrix(matrix, len_x, len_y, n):
# создаю матрицу
new_matrix = [[0 for i in range(len_x)] for j in range(len_y)]

for i in range(0,len_y):
for j in range(0,len_x):
# Умнажаю число из матрицы на число
new_matrix[i][j] = matrix[i][j]*n

return new_matrix

Answer 1

visph ,
yes, you are right, thanks for reminding.

Answer 2

Если используете двумерный массив, можно обойтись без новой матрицы и параметров длина/высота. Передайте копию массива в качестве аргумента функции и умножьте на месте.

https://code.sololearn.com/cr2401Rna3e7/?ref=app

Answer 3

Vitaly Sokol

you only made a shallow copy of the 2d list... you must at least copy the content of the outer list ;)

print(multiply_([r[:] for r in matrix], 10))

Answer 4

Vitaly Sokol you could also use the deepcopy function from the copy module (but you know that as you've just upvoted the post where I shared the link in another thread) ;)

Answer 5

what is your problem?

your function seems to work fine, at least if you use len_x argument as columns length (inner lists) and len_y as rows length (outer list)...

Answer 6

Here’s an example of how to multiply two matrices:

https://code.sololearn.com/cJd1d38NOxPe/?ref=app