And excel conditional maximum data frame python

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https://blog.csdn.net/qq_41858657/article/details/103374630
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https://blog.csdn.net/weixin_37855575/article/details/82288011
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detail about the subject, the examination has rebuilt the students take the exam several times the highest score in a data box and delete the other
to a contest Excel and Python are:

Excel：

=MAXIFS($G:$G,$A:$A,A2)

As shown in Table:
Because data security, show only a desired portion, A XH as a student number, G KCCJ as the high number of results, a final high as the highest number of selected results.

This will last a drop-down to complete.
Then preserved the original number of high scores can be deleted, re-use index will learn Student ID number duplicate columns delete, delete duplicates the data stored in Excel is complete.

python：

Import csv

import pandas as pd
import numpy as np
df=pd.read_csv('E:\\项目\\高数分析\\高数分析\\数学公共课考试成绩\\高数成绩.csv',sep=',')

Integrated into an operation code:

df3=df.loc[df.reset_index().groupby(['XH'])['KCCJ'].idxmax()]

Re-export

##保存入csv
df3.to_csv('E:\\项目\\高数分析\\高数分析\\数学公共课考试成绩\\高数成绩2.csv',index=False,header=False)

Elaborate a code that did things:

##对df进行索引
df=df.set_index(keys=['XH'])

##对df重新设置索引
df1=df.reset_index().groupby(['XH'])
df1.groups

#指定各groups中某一列，并idxmax()提取该列最大值的索引
df2=df.reset_index().groupby(['XH'])['KCCJ'].idxmax()

##利用iloc选取行数据
df.iloc[df2]

It can also be used iloc index

##loc索引为具体值索引
df.reset_index().loc[df2]

## Finally, the integration of the code
DF3 = df3.reset_index ()
df3.head ()