Convert values in a column to a single row Python

Question

I have a pandas dataframe that looks like this:

Area1  Area2 
  1      2      
  1      4
  1      5
  1      9
  2      8
  2      16
  2      4
  2      1
  3      8
  3      9

How can I convert 'Area2' column so that it becomes a list of values for each 'Area1' column

So the output I would want is:

Area1     Area2 
  1      2, 4, 5, 9     
  2      8, 16, 4, 1
  3      8, 9

I have done this in R previously:

df %>% group_by(Area1) %>% summarise(Area2= toString(sort(unique(Area2)))) 

I have been trying out groupby() and agg() but have had no success.

Could someone explain what I can use once I have grouped the data using df.groupby('Area1')

Many thanks in advance for any suggestions.

Answer 1

You can groupby and apply list

import pandas as pd
df=pd.read_csv("test.csv")
df.groupby('Area1')['Area2'].apply(list)

Answer 2

The R snippet does string concatenation.

The following line keeps the original type of Area2 .

import pandas as pd

df.groupby('Area1').Area2.apply(pd.Series.tolist).reset_index()