Pandas: LEFT OUTER JOIN where (ON) 2 Conditions that Match

Question

I have 2 Dataframes that I'd like to combine in Pandas where two 2 conditions are met, but I'm not successfully getting there. Thanks in advance for assistance!

df1
    A    B    C
0   1    2    3
1   4    5    6
2   7    8    9

df2
    A    B    F
0   1    2    cat
1   4    5    dog
2   7    8    moose

Desired Result

df3
    A    B    C    F
0   1    2    3    cat
1   4    5    6    dog
2   7    8    9    moose

Attempts to merge that are failing that are failing:

pd.merge(df1, df2, on='A' & 'B', how='left')
pd.merge(df1, df2, on('A' & 'B'), how='left')
pd.merge(df1, df2, on='A' & on='B',how='left')

jezrael · Accepted Answer · 2016-01-20T07:13:25.223

1

Maybe you can try add to merge multiple join keys on=['A','B']:

print pd.merge(df1, df2, on=['A','B'], how='left')

   A  B  C      F
0  1  2  3    cat
1  4  5  6    dog
2  7  8  9  moose

Docs.

edited Jan 20 '16 at 07:13

answered Jan 20 '16 at 07:05

jezrael

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Brilliant! Exactly what I was looking for! Thanks, @jezrael! – Levine Jan 20 '16 at 07:07
And welcome to Stack Overflow. You can check [tour](http://stackoverflow.com/tour). – jezrael Jan 20 '16 at 07:11
Thanks! Great to be here! :-) – Levine Jan 20 '16 at 07:14

Pandas: LEFT OUTER JOIN where (ON) 2 Conditions that Match

Desired Result

1 Answers1