how to duplicate a row with an element in a list in python pandas

Question

I have a data frame that looks like below:

import pandas as pd
import numpy as np

df = pd.DataFrame({'id':[1,2,3],'class':[7,5,3], 'grades':[[4,5,6],[8],[]]})

what I am trying to do here is that I want to duplicate each row for the number of element in the list in "grades" column.

It is kind of hard to explain, so it will be better to show the desired output.

output = pd.DataFrame({'id':[1,1,1,2,3],'class':[7,7,7,5,3], 'grades':[4,5,6,8, np.nan]})

I have look through some solutions, but could not figure out a way.

It will be great if someone can provide a guidance.

Andy L. · Accepted Answer · 2020-08-15 03:21:05Z

3

it is explode

df.explode('grades')

Out[11]:
   id  class grades
0   1      7      4
0   1      7      5
0   1      7      6
1   2      5      8
2   3      3    NaN

answered Aug 15, 2020 at 3:21

Andy L.

25.3k4 gold badges20 silver badges30 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

how to duplicate a row with an element in a list in python pandas

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related