Multiplicación de arrays en NumPy

Veamos cómo calcular la multiplicación de arrays con NumPy. Usaremos el método numpy.dot() para encontrar el producto de 2 arrays.

For example, for two matrices A and B.
A = [[1, 2], [2, 3]]
B = [[4, 5], [6, 7]]

So, A.B = [[1*4 + 2*6, 2*4 + 3*6], [1*5 + 2*7, 2*5 + 3*7]
So the computed answer will be: [[16, 26], [19, 31]]

En Python, el método numpy.dot() se usa para calcular el producto escalar entre dos arrays.

Ejemplo 1: Multiplicación de arrays de 2 arrays cuadradas.

# importing the module
import numpy as np
  
# creating two matrices
p = [[1, 2], [2, 3]]
q = [[4, 5], [6, 7]]
print("Matrix p :")
print(p)
print("Matrix q :")
print(q)
  
# computing product
result = np.dot(p, q)
  
# printing the result
print("The matrix multiplication is :")
print(result)

Producción :

Matrix p :
[[1, 2], [2, 3]]
Matrix q :
[[4, 5], [6, 7]]
The matrix multiplication is :
[[16 19]
 [26 31]]

Ejemplo 2: Multiplicación de arrays de 2 arrays rectangulares.

# importing the module
import numpy as np
  
# creating two matrices
p = [[1, 2], [2, 3], [4, 5]]
q = [[4, 5, 1], [6, 7, 2]]
print("Matrix p :")
print(p)
print("Matrix q :")
print(q)
  
# computing product
result = np.dot(p, q)
  
# printing the result
print("The matrix multiplication is :")
print(result)

Producción :

Matrix p :
[[1, 2], [2, 3], [4, 5]]
Matrix q :
[[4, 5, 1], [6, 7, 2]]
The matrix multiplication is :
[[16 19  5]
 [26 31  8]
 [46 55 14]]