matrix multiplication
Seb
spluque at gmail.com
Sun Feb 25 12:45:51 EST 2018
Hello,
The following is an example of an Nx3 matrix (`uvw`) representing N
vectors that need to be multiplied by a 3x3 matrix (generated by
`randint_mat` function) and store the result in `uvw_rots`:
---<--------------------cut here---------------start------------------->---
import numpy as np
def randint_mat(x):
return np.random.randint(x, size=(3, 3))
np.random.seed(123)
uvw = np.random.randn(1000, 3)
maxint = np.random.randint(1, 10, size=uvw.shape[0])
uvw_rots = np.empty_like(uvw)
for i, v in enumerate(maxint):
mati = randint_mat(v)
uvw_roti = np.dot(uvw[i], mati)
uvw_rots[i] = uvw_roti
---<--------------------cut here---------------end--------------------->---
Is there a better (faster) approach than looping through the rows of uvw
as shown?
Thanks,
--
Seb
More information about the Python-list
mailing list