在 Pandas 中对组内的列进行排序

Question

我是熊猫新手。我正在尝试对每个组中的一列进行排序。到目前为止，我能够将第一列和第二列值组合在一起并计算第三列中的平均值。但我仍在努力对第三列进行排序。

This is my input dataframe This is my dataframe after applying groupby and mean function

我使用以下代码行对输入数据框进行分组， df_o=df.groupby(by=['Organization Group','Department']).agg({'Total Compensation':np.mean})

请告诉我如何使用 pandas 对第一列中每个组的最后一列进行排序。

Answer 1

看来你需要sort_values:

#for return df add parameter as_index=False
df_o=df.groupby(['Organization Group','Department'], 
                 as_index=False)['Total Compensation'].mean()
df_o = df_o.sort_values(['Total Compensation','Organization Group'])

示例：

df = pd.DataFrame({'Organization Group':['a','b','a','a'],
                   'Department':['d','f','a','a'],
                   'Total Compensation':[1,8,9,1]})

print (df)
  Department Organization Group  Total Compensation
0          d                  a                   1
1          f                  b                   8
2          a                  a                   9
3          a                  a                   1

df_o=df.groupby(['Organization Group','Department'], 
                as_index=False)['Total Compensation'].mean()
print (df_o)
  Organization Group Department  Total Compensation
0                  a          a                   5
1                  a          d                   1
2                  b          f                   8

df_o = df_o.sort_values(['Total Compensation','Organization Group'])
print (df_o)
  Organization Group Department  Total Compensation
1                  a          d                   1
0                  a          a                   5
2                  b          f                   8