How to make a pandas crosstab with percentages?

Question

Given a dataframe with different categorical variables, how do I return a cross-tabulation with percentages instead of frequencies?

df = pd.DataFrame({\'A\' : [\         


        

Answer 1

Another option is to use div rather than apply:

In [11]: res = pd.crosstab(df.A, df.B)

Divide by the sum over the index:

In [12]: res.sum(axis=1)
Out[12]: 
A
one      12
three     6
two       6
dtype: int64

Similar to above, you need to do something about integer division (I use astype('float')):

In [13]: res.astype('float').div(res.sum(axis=1), axis=0)
Out[13]: 
B             A         B         C
A                                  
one    0.333333  0.333333  0.333333
three  0.333333  0.333333  0.333333
two    0.333333  0.333333  0.333333