python中如何处理异常值

import pandas as pd #导入pandas库

data=pd.DataFrame({'name':['A','B','C','D','E','F','G'],'cost':[2,127,4,6,3,13,14],'sales':[13,18,32,54,23,33,44]})

print(data)

df1=data.copy()#为了不影响原始数据集，复制数据集data

print(df1)

df1['cost']=(df1['cost']-df1['cost'].mean())/df1['cost'].std()#标准化cost_z列

df1['sales']=(df1['sales']-df1['sales'].mean())/df1['sales'].std()#标准化cost_z列

df1['sales']

print(df1)

df1['cost'].abs()>2#判断数据是否异常

data[df1['cost'].abs()>2]#取出原数据集中的异常点