Množenje matrik v NumPy
Poglejmo, kako izračunati množenje matrik z NumPy. Uporabljali bomo numpy.dot() metoda za iskanje produkta 2 matrik.
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]]
V Pythonu se metoda numpy.dot() uporablja za izračun pikčastega produkta med dvema nizoma.
Primer 1: Matrično množenje dveh kvadratnih matrik.
# 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)> |
Izhod:
Matrix p : [[1, 2], [2, 3]] Matrix q : [[4, 5], [6, 7]] The matrix multiplication is : [[16 19] [26 31]]
Primer 2: Matrično množenje 2 pravokotnih matrik.
# 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)> |
Izhod:
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]]
