Concatenate 2 dataframes having different values

Question

we have the following two dataframes respectively.

Dataframe 1:
id =[30,30]
month =[1,3]
less_data =['pravin','shashi']

df = pd.DataFrame(list(zip(id,month,less_data)),columns =['id','month','less_data'])

Dataframe 2:
id =[30,30]
month =[1,2]
less_data =['amol','pinak']


df2 = pd.DataFrame(list(zip(id,month,less_data)),columns =['id','month','zero_data'])

and expected output:

id  month   less_data   zero_data
30  1       pravin      amol
30  2                   pinak
30  3       shashi

How can I use pd.concat to achieve this or suggest better solution for the same

score 2 · Accepted Answer · answered Dec 30 '20 at 06:01

2

use pd.concat:

dfn = pd.concat([
           df.set_index(['id','month']),
          df2.set_index(['id','month'])
        ], axis = 1).reset_index()

answered Dec 30 '20 at 06:01

Ferris

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score 1 · Answer 2 · edited Dec 30 '20 at 05:57

1

You can do an outer join:

df.join(df2.set_index(['id', 'month']), how='outer', on=['id', 'month'])

edited Dec 30 '20 at 05:57

Michael Szczesny

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answered Dec 30 '20 at 05:52

Baran Karakus

193
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Your quotes were not valid python quotes and please use code formatting for your code. – Michael Szczesny Dec 30 '20 at 05:57

Vaebhav · Answer 3 · 2020-12-30T06:08:06.893

1

You can use pd.merge on month and id

import pandas as pd
import numpy as np

id =[30,30]
month =[1,3]
less_data =['pravin','shashi']

df = pd.DataFrame(list(zip(id,month,less_data)),columns =['id','month','less_data'])

id =[30,30]
month =[1,2]
less_data =['amol','pinak']


df2 = pd.DataFrame(list(zip(id,month,less_data)),columns =['id','month','zero_data'])

##### Merge can be thought of joins in SQL
>>> df_merge = pd.merge(df,df2,on=['id','month'],how='outer')
>>> df_merge
   id  month less_data zero_data
0  30      1    pravin      amol
1  30      3    shashi       NaN
2  30      2       NaN     pinak

edited Dec 30 '20 at 06:08

answered Dec 30 '20 at 05:53

Vaebhav

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If You can see, my expected output is not like that, id row value :: 30 is missing – Amol Dec 30 '20 at 05:59
Updated the answer to accommodate the `id` , do accept the answer if it solves your question :) – Vaebhav Dec 30 '20 at 06:02
Yep totally agree with that , I have removed it from the answer – Vaebhav Dec 30 '20 at 06:08

Concatenate 2 dataframes having different values

3 Answers3