CODEWITHSUNDEEP
pythonpandasdataframe
Jason Melo Hall
Jason Melo Hall

Reputation: 662

Adding A Specific Column from a Pandas Dataframe to Another Pandas Dataframe

I am trying to add a column to a pandas dataframe (df1) that has a unique identifier ('id') column from another dataframe (df2) that has the same unique identifier ('sameid'). I have tried merge, but I need to only add one specific column ('addthiscolumn') not all of the columns. What is the best way to do this?

print df1
   'id'  'column1'
0  aaa   randomdata1
1  aab   randomdata2
2  aac   randomdata3
3  aad   randomdata4

print df2
   'sameid'  'irrelevant' 'addthiscolumn'
0   aaa        irre1       1234
1   aab        irre2       2345
2   aac        irre3       3456
3   aad        irre4       4567
4   aae        irre5       5678
5   aad        irre6       6789

Desired Result

print df1
   'id'  'column1'    'addthiscolumn'
0  aaa   randomdata1   1234
1  aab   randomdata2   2345
2  aac   randomdata3   3456
3  aad   randomdata4   4567

Upvotes: 3

Views: 1179

Answers (1)

Alexander
Alexander

Reputation: 109696

Because you just want to merge a single column, you can select as follows:

df1.merge(df2[['sameid', 'addthiscolumn']], left_on='id', right_on='sameid')

Upvotes: 3

Related Questions