Pandas get_dummies to create one hot with separator = ' ' and with character level separation [duplicate]

问题

This question already has an answer here:

Quickest way to make a get_dummies type dataframe from a column with a multiple of strings (1 answer)

Closed 2 years ago.

df = pd.DataFrame(["c", "b", "a p", NaN, "ap"])
df[0].str.get_dummies(' ')

The above code prints something like this.

       a   p    b    c ap 
0      0   0    0    1  0
1      0   0    1    0  0 
2      1   1    0    0  0
3      0   0    0    0  0
4      0   0    0    0  1  

The required output is the following:

       a   p    b    c  
0      0   0    0    1 
1      0   0    1    0  
2      1   1    0    0 
3      0   0    0    0 
4      1   1    0    0  

I am sure it's bit tricky. Any help is appreciated.

回答1:

You can use str.get_dummies

df[0].str.get_dummies(' ')


    air bus car plane
0   0   0   1   0
1   0   1   0   0
2   1   0   0   1

回答2:

IIUC str.get_dummies

df[0].str.get_dummies(sep=' ')
Out[745]: 
   air  bus  car  plane
0    0    0    1      0
1    0    1    0      0
2    1    0    0      1

Or

pd.get_dummies(pd.DataFrame(df[0].str.split().tolist()).stack()).sum(level=0)
Out[754]: 
   air  bus  car  plane
0    0    0    1      0
1    0    1    0      0
2    1    0    0      1

来源：https://stackoverflow.com/questions/49420338/pandas-get-dummies-to-create-one-hot-with-separator-and-with-character-lev