python - pandas dataframe，如何获得某个索引的平均值

Question

例如，我有一个这样的数据框:

Age Gender  
20   Male  
10   Male  
18   Female  
15   Male  
19   Female  
17   Female  

我怎样才能像这样的 DataFrame:

Age  Gender  
15   Male  
18   Female  

新DataFrame中的年龄分别是对应Gender的旧DataFrame的平均年龄。

Answer 1

In [51]: df.groupby('Gender', as_index=False).Age.mean()
Out[51]:
   Gender  Age
0  Female   18
1    Male   15

How can I make the result DataFrame a Series with Gender as keys/index?

In [61]: s = df.groupby('Gender').Age.mean()

In [62]: s
Out[62]:
Gender
Female    18
Male      15
Name: Age, dtype: int64

In [63]: type(s)
Out[63]: pandas.core.series.Series