Vegem com calcular la multiplicació de matrius amb NumPy. Farem servir el numpy.dot() mètode per trobar el producte de 2 matrius.
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]]>
A Python, el mètode numpy.dot() s'utilitza per calcular el producte escalat entre dues matrius.
Exemple 1: Multiplicació matricial de 2 matrius quadrades.
en lloc de
# 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)> |
>
>
Sortida:
Matrix p : [[1, 2], [2, 3]] Matrix q : [[4, 5], [6, 7]] The matrix multiplication is : [[16 19] [26 31]]>
Exemple 2: Multiplicació matricial de 2 matrius rectangulars.
# 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)> |
>
>
Sortida:
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]]>