I have the following example data set
| A | B | C | D |
|---|---|---|---|
| foo | 0 | 1 | 1 |
| bar | 0 | 0 | 1 |
| baz | 1 | 1 | 0 |
How could extract the column names of each 1 occurrence in a row and put that into another column E so that I get the following table:
| A | B | C | D | E |
|---|---|---|---|---|
| foo | 0 | 1 | 1 | C, D |
| bar | 0 | 0 | 1 | D |
| baz | 1 | 1 | 0 | B, C |
Note that there can be more than two 1s per row.
CodePudding user response：
You can use DataFrame.dot.
df['E'] = df[['B', 'C', 'D']].dot(df.columns[1:] ', ').str.rstrip(', ')
df
A B C D E
0 foo 0 1 1 C, D
1 bar 0 0 1 D
2 baz 1 1 0 B, C
Inspired by jezrael's answer in this post.