具有相同/相同列名的熊猫 get_dummies

Question

I have

In [122]: d=pandas.DataFrame({'d_1':['a','x'],'d_2':['x','y']})

In [123]: d
Out[123]: 
  d_1 d_2
0   a   x
1   x   y

I want:

    a   x   y 
0   1   1   0 
1   0   1   1

I do not want to use

In [139]: pandas.get_dummies(d)
Out[139]: 
   d_1_a  d_1_x  d_2_x  d_2_y
0    1.0    0.0    1.0    0.0
1    0.0    1.0    0.0    1.0

Because d_1_x and d_2_x are considered distinct by this function, which requires too much memory for my application.

I do however want to use get_dummies because it is fast; so, I tried to rename the columns and apply get_dummies

In [124]: d.columns=['d' for el in d.columns]

In [141]: d
Out[141]: 
   d  d
0  a  x
1  x  y

In [151]: pandas.get_dummies(d)
Out[151]: 
   d_('d',)  d_('d',)
0       1.0       1.0
1       1.0       1.0

Answer 1

You can try something like this:

import pandas as pd
d.apply(lambda x: pd.Series(1, x), 1).fillna(0)

#     a   x   y
#0  1.0 1.0 0.0
#1  0.0 1.0 1.0