python - 跨行对Pandas数据框进行分组

我有一个这样的csv：

client1,client2,client3,client4,client5,client6,amount
,,,Comp1,,,4.475000
,,,Comp2,,,16.305584
,,,Comp3,,,4.050000
Comp2,Comp1,,Comp4,,,21.000000
,,,Comp4,,,30.000000
,Comp1,,Comp2,,,5.137500
,,,Comp3,,,52.650000
,,,Comp1,,,2.650000
Comp3,,,Comp3,,,29.000000
Comp5,,,Comp2,,,20.809000
Comp5,,,Comp2,,,15.100000
Comp5,,,Comp2,,,52.404000

在将其读入pandas数据框df之后，我想将其聚合为两个步骤：
步骤1：
首先，我将金额相加：

client1 client2 client3 client4 client5 client6  amount
                        Comp1                    7.125000
                        Comp2                    16.305584
                        Comp3                    56.700000
                        Comp4                    30.000000
         Comp1          Comp2                    5.137500
Comp2    Comp1          Comp4                    21.000000
Comp3                   Comp3                    29.000000
Comp5                   Comp2                    88.313000

然后，我想按每个客户机名称进行聚合，这样如果像组5中那样涉及多个客户机，那么5.1375必须在Comp1和Comp2之间平均分配。这样试过了：

df.groupby(['client1','client2','client3','client4','client5','client6']).apply(lambda x: x['amount'].sum()/len(x) if x.any().nunique()>=1 else x['amount'].sum())



client1 client2 client3 client4 client5 client6 0
0                           Comp1                   3.562500
1                           Comp2                   16.305584
2                           Comp3                   28.350000
3                           Comp4                   30.000000
4           Comp1           Comp2                   5.137500
5   Comp2   Comp1           Comp4                   21.000000
6   Comp3                   Comp3                   29.000000
7   Comp5                   Comp2                   29.437667

预期产量为：

Client Amount
Comp1  4.475+21/3+5.1375/2+2.65 = 16.69375
Comp2  16.305584+21/3+20.809/2+15.10/2+52.404/2 = 67.462084
Comp3  4.05+52.65+29 = 85.7
Comp4  21/3+30 = 37
Comp5  20.809/2+15.10/2+52.404/2 = 44.1565

我试着用sum(axis=0)但没用。

最佳答案

我们这里可以用点数学

cols = ['amount']
# Divide the amount by non null fields
df['new'] = df['amount']/df.drop(cols,1).notnull().sum(1)

#Set the index as new by droping amount column, unstack and drop the nans.
x = df.drop(cols,1).set_index('new').unstack().dropna()

#Create dataframe just from amount and the clients
ndf = pd.DataFrame({'amount':x.index.droplevel(0).values,'clients':x.values})

#Groupby client and get the sum
ndf.groupby('clients').sum()

输出：
数量
客户
综合16.360417
公司编号：69.697501
公司3 85700000
综合4 36.666667
综合5 44.15650

关于python - 跨行对Pandas数据框进行分组，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/46995997/