np.sum

import numpy as np
a = np.sum([[1,2],[2,3]])
print(a)#8,矩阵中所有元素相加
b = np.sum([[1,2],[2,3]],axis=0)
print(b)#[3 5],每列之和
c = np.sum([[1,2],[4,3]],axis=1)
print(c)#[3 7],每行之和
d = np.sum([0.5, 0.7, 1.2, 1.5], dtype=np.int32)
print(d)#2,整数部分相加