python之Pandas之从行数中获取汇总数据框

给定这个 DataFrame:

    bowl    cookie 
0   one     chocolate 
1   two     chocolate 
2   two     chocolate 
3   two     vanilla 
4   one     vanilla 
5   one     vanilla 
6   one     vanilla 
7   one     vanilla 
8   one     vanilla 
9   two     chocolate 

我想获得以下总结的 DataFrame:

        vanilla     chocolate 
one     5           1 
two     1           3 

除了手动进行:

vanilla_bowl1 = len(df_picks[(df_picks['bowl'] == 'one') & (df_picks['cookie'] == 'vanilla')]) 
vanilla_bowl2 = len(df_picks[(df_picks['bowl'] == 'two') & (df_picks['cookie'] == 'vanilla')]) 
chocolate_bowl1 = ... 
chocolate_bowl2 = ... 

有没有办法用 Pandas 在一次操作中做到这一点？

注意:我查看了 df.pivot()，如果我添加列 count 等于，这将起作用每行 1:

    bowl    cookie      count 
0   one     chocolate       1 
1   two     chocolate       1 
2   two     chocolate       1 
3   two     vanilla         1 
4   one     vanilla         1 
5   one     vanilla         1 
6   one     vanilla         1 
7   one     vanilla         1 
8   one     vanilla         1 
9   two     chocolate       1 

然后

df.pivot(index='bowl', columns='cookie', values='count') 

但是，我想知道是否有更直接的方法，不需要首先添加 count 列。

请您参考如下方法:

最简洁的方式可能是pandas.crosstab函数:

>>> pandas.crosstab(d.bowl, d.cookie) 
cookie  chocolate  vanilla 
bowl                       
one             1        5 
two             3        1