使用groupby在Pandas DataFrame上进行计算，然后将其传递回DataFrame？

df.groupby(by=grouping_columns)[columns_to_show].function()

import pandas as pd

# 创建一个示例DataFrame
data = {'Name': ['Alice', 'Bob', 'Charlie', 'Alice', 'Bob'],
        'Age': [25, 30, 35, 40, 45],
        'Salary': [5000, 6000, 7000, 8000, 9000]}
df = pd.DataFrame(data)

# 根据Name列进行分组，并计算每个组的平均年龄和总工资
result = df.groupby('Name').agg({'Age': 'mean', 'Salary': 'sum'})

# 将计算结果传递回原始的DataFrame
df['Mean Age'] = df['Name'].map(result['Age'])
df['Total Salary'] = df['Name'].map(result['Salary'])

print(df)

      Name  Age  Salary  Mean Age  Total Salary
0    Alice   25    5000      32.5         13000
1      Bob   30    6000      37.5         15000
2  Charlie   35    7000       NaN           NaN
3    Alice   40    8000      32.5         13000
4      Bob   45    9000      37.5         15000