10-pandas多层索引操作

import numpy as np
import pandas as pd
index=[("beijing",2007),("beijing", 2017),
       ("beijing", 2027),("shenzhen",2007),
       ("shenzhen",2017),("shenzhen",2027)]
money=np.random.rand(6)
Mindex=pd.MultiIndex.from_tuples(index)
city=pd.DataFrame(money,index=Mindex)
print(city[0])#代表全部数据
print(city.loc["beijing"])#取出行beijing
print(city.iloc[0])#取出第一行

idx=pd.IndexSlice#处理索引
print(city.loc[idx["beijing"],idx[:]])#取出北京
print(city.loc[idx["beijing",2007],idx[:]])#取出北京2007
print(city.loc[idx[:,2027],idx[:]])#取出所有2027

print(city.unstack(level=0))#生成表格
print(city.unstack(level=1))#生成表格

print(city.mean(level=0))#城市算平均值
print(city.mean(level=1))#年度算平均值，聚合操作
print(city.sum(level=0))#根据城市求和
print(city.sum(level=1))#根据年度求和
print(city.max(level=0))
print(city.min(level=1))