merging dataframes (python pandas)

merging dataframes (python pandas)



I have two dataframes df1 df1 and df2 df2
I want to merge them using python pandas without creating the Cartesian product.Sample output would look like this output How should I do it?



Currently,I am using
df3=pd.merge(df1,df2,on='id',how='left') but it's giving me cross product.The resultant dataframe df3 contains 14 records 6 for id=1 and 8 for id=2.



Thanks,






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– Alex
Sep 18 '18 at 16:17




1 Answer
1



You may need an additional key for help, create by cumcount


cumcount


df1['Helpkey']=df1.groupby('id').cumcount()
df2['Helpkey']=df2.groupby('id').cumcount()

df1.merge(df2,how='left').drop('Helpkey',1)






Thank You!! It worked when I replaced how='left' with how='outer'..I really appreciate your help

– RSK
Sep 18 '18 at 16:23






@RohanKulkarni if this work would you like accept it ? check mark at the left

– Wen-Ben
Sep 18 '18 at 16:24



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