How to assign/add columns from one data frame to another which contains duplicate values in pandas?

Question

I have df1:

     id  value1 value2
 0   A_1  123   878
 1   A_2  251   356
 2   A_3  222   332

and df2:

    id
0   A_2
1   A_3
2   A_3
3   A_1
4   A_1
5   A_4

desired output:

    id   value1 value2
0   A_2    251      356
1   A_3    222      332
2   A_3    222      332
3   A_1    123      878
4   A_1    123      878
5   A_4    NA        NA

is there any fastest way to do this? Thanks!

https://stackoverflow.com/questions/67907426/credit-card-transaction-classification-in-python?noredirect=1#comment120028270_67907426 — The shape, Jun 13 '21 at 18:27

score 1 · Accepted Answer · answered Jun 13 '21 at 18:30

1

You should be able to accomplish this with a left-join:

df2.merge(df1, on='id', how='left')

See this blog post for more details, or the official docs.

answered Jun 13 '21 at 18:30

Will Da Silva

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How to assign/add columns from one data frame to another which contains duplicate values in pandas?

1 Answers1