如何将 pandas dataframe 列拆分为出现矩阵

Question

I want to divide column of lists to x (number of unique values) columns with 1 if exists in row and 0 if it doesn't For example:

         animals
0  dog;mouse;cat
1        cat;dog
2            dog
3      mouse;cat
4        dog;cat

to:

   dog  mouse  cat
0    1      1    1
1    1      0    1
2    1      0    0
3    0      1    1
4    1      0    1

Answer 1

Use pandas.Series.str.get_dummies :

df['animals'].str.get_dummies(sep=';')

output:

   cat  dog  mouse
0    1    1      1
1    1    1      0
2    0    1      0
3    1    0      1
4    1    1      0