python中sum函数

版本：python3

 python自带的sum函数（或者Numpy中的sum函数），无参时，所有全加；axis=0，按列相加；axis=1，按行相加

import numpy as np#python中自带的sumprint(sum([[1,2,3],[4,5,5]]))print(sum([[1,2,3],[4,5,5]],axis=0))print(sum([[1,2,3],[4,5,5]],axis=1))#Numpy中的suma = np.sum([[1,2,3], [4,5,5]]) #无参print(a)print(a.shape)a = np.sum([[1,2,3], [4,5,5]],axis=0) #axis=0, 按列相加print(a)print(a.shape)a = np.sum([[1,2,3], [4,5,5]],axis=1) #axis=1, 按行相加print(a)print(a.shape)

20
[5 7 8]
[ 6 14]
20
()
[5 7 8]
(3,)
[ 6 14]
(2,)