Pandas: efficient way to transform DataFrame layout in one step without loops

Question

df = pd.DataFrame(['Ottawa City Council','City of Toronto'], columns = ['Entity'])

How can I change the layout of df to look as below in one step? I know I can do it with loops but I'm seeking the most efficient way as I have 1.2 million rows so it will take hours. Thanks.

score 1 · Accepted Answer · answered Dec 14 '19 at 20:55

1

First you have to create the new column, for now with a list of words:

df['Word'] = df.Entity.str.split(' ')

Then explode it (a new function in Pandas version 0.25):

df.explode('Word')

answered Dec 14 '19 at 20:55

Valdi_Bo

27,886
3
21
36

score 1 · Answer 2 · answered Dec 14 '19 at 20:56

1

df['Word'] = [x.split() for x in df.Entity] df.explode('Word') # pandas >= 25.0

answered Dec 14 '19 at 20:56

Rene

3,062
3
17
41

Pandas: efficient way to transform DataFrame layout in one step without loops

2 Answers2