python - 计算分组 pandas 数据框中的总和

Question

我需要表达数据中每一行占整体的百分比。技巧是我需要通过 groupby 调用将百分比绑定(bind)到父分组。我的 DF 目前看起来像这样:

category    Segment     Pageviews
Sitting     Age 25-34   2268
            Age 35-44   2942
            Age 45-53   2209
            Age 55+     3317
Standing    Age 25-34   2193
            Age 35-44   1664
            Age 45-53   1874
            Age 55+     1647
Kneeling    Age 25-34   680
            Age 35-44   494
            Age 45-53   876
            Age 55+     1489

我希望实现的是每个年龄范围的坐、站、跪分别所占的百分比。

即

category    Segment     Pageviews  Percentage
Sitting     Age 25-34   2268       21%
            Age 35-44   2942       27%
            Age 45-53   2209       20%
            Age 55+     3317       31%
Standing    Age 25-34   2193       ...
            Age 35-44   1664       ... 
            Age 45-53   1874       ...
            Age 55+     1647
Kneeling    Age 25-34   680
            Age 35-44   494
            Age 45-53   876
            Age 55+     1489

Answer 1

您可以使用:

>>> df['Percentage'] = df.groupby('category')['Pageviews']\
                         .apply(lambda g: 100*g / g.sum())

    category   Segment  Pageviews  Percentage
0    Sitting  Age25-34       2268   21.125186
1    Sitting  Age35-44       2942   27.403130
2    Sitting  Age45-53       2209   20.575633
3    Sitting    Age55+       3317   30.896051
4   Standing  Age25-34       2193   29.723502
5   Standing  Age35-44       1664   22.553538
6   Standing  Age45-53       1874   25.399837
7   Standing    Age55+       1647   22.323123
8   Kneeling  Age25-34        680   19.214467
9   Kneeling  Age35-44        494   13.958745
10  Kneeling  Age45-53        876   24.752755
11  Kneeling    Age55+       1489   42.074032