DataFame分组聚合操作groupby()

分组聚合操作

import pandas as pd
import numpy as np
#首先构建一个dataframe
data_dict={
     
"color":["black","red","green","red","green"],
"city":["pen","pencil","pencil","eraser","pen"],
"price1":[5,4,1,3,2],
"price2":[7,2,3,8,3]
}
data_df=pd.DataFrame(data=data_dict)
data_df

#以color分组，以price1进行分组
data_df.groupby(by="color")["price1"].max()#打印出color里面price1的最大值

#也可以用这种方法
data_df["price1"].groupby(data_df["color"]).max()

总结

如果您发现我写的有错误，欢迎在评论区，批评指正。