numpy中...和:的区别

...代指多个:,:。

import numpy as np

w1=[]

for j in range(5):

    if j!=0:

        w1.append((j*1,j*1+1,0))

w1=np.array(w1)

#print(w1)

#print(w1[:,:-1])

e=w1[:,:-1]

br=np.broadcast_to(e[None],(4,4,2))

#print(e[:,None,:])

#print(br)

ne=e[:,None,:]-br

ne=np.reshape(ne,(-1,1,2))

grid = np.arange(5, dtype=np.float32).reshape(1, -1, 1)

point=grid*ne/10+ne.reshape((-1,1,2))

#print(point)

x = point[..., 0].ravel()#x等于point[:,:,0].ravel。