numpy：数据类型转换

import numpy as np
vector=np.array(['0','5','10'])
vector=vector.astype(float)
print(vector)

输出

[ 0.  5. 10.]

vector=np.array(['0','5','10','a'])
vector=vector.astype(float)

报错

ValueError   Traceback (most recent call last) 
 in 
----> 1 vector=vector.astype(float)

ValueError: could not convert string to float: 'a'