pandas groupby as list 使用 agg 和 apply 函数返回空

Question

当尝试根据列组（即“master_mac”和“slave_mac”）将“rssi”列作为列表返回时，pandas 数据框返回空，下面是我的输入数据框

   master_mac    slave_mac        uuid           rawData   rssi            
0  ac233fc01403  ac233f26492b     e2c56db5       NaN       -23                                                  
1  ac233fc01403  ac233f26492b     e2c56db5       NaN       -28                                                  
2  ac233fc01403  ac233f26492b     e2c56db5       NaN       -32                                                   
3  ac233fc01403  ac233f26492b     e2c56db5       NaN       -37
4  ac233fc01403  e464eecba5eb     NaN            590080    -25         
5  ac233fc01403  ac233f26492b     e2c56db5       NaN       -29 
6  ac233fc01403  ac233f26492b     e2c56db5       NaN       -31                                                    
7  ac233fc01403  ac233f26492b     e2c56db5       NaN       -30

结果应该是，

   master_mac    slave_mac     uuid     rawData  rssi            
0  ac233fc01403  ac233f26492b  e2c56db5 NaN      [-23,-28,-32,-37,-29,-31,-30]                                                  
1  ac233fc01403  e464eecba5eb     NaN   590080   [-25]         

而当我使用时，

df.groupby(['master_mac', 'slave_mac','uuid','rawData'])['rssi'].apply(list)

同样的回报，

Series([], Name: rssi, dtype: float64)

使用应用时，

df.groupby(['master_mac','slave_mac','uuid','rawData']).apply(lambda x: x['rssi'].values)

它返回为，

Empty DataFrame
Columns: []
Index: []

在使用 agg 时，

df.groupby(['master_mac','slave_mac','uuid','rawData']).agg(lambda x: list(x))

返回为，

Empty DataFrame
Columns: []
Index: []

Answer 1

试试

df.groupby(['master_mac', 'slave_mac','uuid','rawData'])['rssi'].agg(lambda x: list(x))