讀取pandas修改單列數據類型

import pandas as pd
import numpy as np

df = pd.read_csv('000917.csv',encoding='gbk')
df = df[df['漲跌幅']!='None']
df['漲跌幅'] = df['漲跌幅'].astype(np.float64)

print(df[df['漲跌幅']>5])