【数据平台】python数据集连接和组合

场景：dataframe之间的链接，以及list之间的组合。

参考：

# -*- coding: utf-8 -*-'''Created on 2017年9月30日@author: Administrator'''import pandas as pdimport itertoolsfrom itertools import product#mergedf1=pd.DataFrame({'name':['z','q','s','l'],'subid':['1','2','',''],'cid':['c1','','c2','c3']})print (df1)df2=pd.DataFrame({'name':['z','q','s','s','g'],'cid':['c1','c2','c2','c3','c1'],'code':['1','2','3','3','2']}) print (df2)#内连接df_inner=pd.merge(df1,df2,on=['name','cid'],how='inner')    print (df_inner)#左连接df_left=pd.merge(df1,df2,on=['name','cid'],how='left')    print (df_left)#右连接df_right=pd.merge(df1,df2,on=['name','cid'],how='right')    print (df_right)#全外连接df_outer=pd.merge(df1,df2,on=['name','cid'],how='outer')    print (df_outer)#joindf1=pd.DataFrame({'name':['z','q','s','l']})print (df1)df2=pd.DataFrame({'cid':['c1','c2','c3']}) print (df2)df_join=df1.join(df2)print (df_join)#元素两两组合-笛卡尔乘积list1=['z','q','s','l']list2=['c1','c2','c3']list3 = [(x,y) for x in list1 for y in list2]print (list3)for x in product(list1, list2):    print (x)for x in product(list1, repeat=4):    print (x)nums = itertools.permutations(list2)#自身组合for x in  nums:    print(x)