13-pandas merge data

import numpy as np
import pandas as pd
#1.完全匹配
df1=pd.DataFrame({"name":["wangchenyang","guanchenhao","dongshuai"],
                  "age":[30,32,33]})
df2=pd.DataFrame({"name":["wangchenyang","guanchenhao","dongshuai"],
                  "tall":[310,312,313]})
print(pd.merge(df1,df2))#一对一归并

#2.不匹配
df1=pd.DataFrame({"name":["wangchenyang","guanchenhao","dongshuai"],
                  "age":[30,32,33]})
df2=pd.DataFrame({"name":["wangchenyang","guanchenhao","guokui"],
                  "tall":[310,312,313]}) 
                  "Age": [30, 32,]})
#. 3.
Print (pd.merge (DF1, DF2)) # default merely merged matching

DF1 = pd.DataFrame ({ "name": [ "wangchenyang", "guanchenhao", "dongshuai"],
df2=pd.DataFrame({"name":["wangchenyang","guanchenhao","guokui"],
                  "tall":[310,312,313]})
df3=pd.DataFrame({"heavy":[100,110,130],
                  "tall":[310,312,313]})
print(pd.merge(pd.merge(df1,df2),df3))#一一匹配

#4.
df1=pd.DataFrame({"name":["wangchenyang","guanchenhao","dongshuai"],
                  "age":[30,32,33]})
df2=pd.DataFrame({"name":["wangchenyang","guanchenhao","guokui"],
                  "tall":[310,312,313]})
df3=pd.DataFrame({"heavy":[100,110,130],
                  "tall":[310,312,313]}) 
DF4 = pd.DataFrame ({ "Heavy": [100,110,130],
                  "Education": [ "degree", "college", "Master"]})
print (pd.merge (pd.merge (df1, df2), pd.merge (df3, df4))) # match twenty-two