How to create a column based on size of a set in pandas












0















I have a dataframe in pandas and I'm using 'set' as an aggregate function in a groupby and I create the following dataframe



A, B, C
1, 2, {nan, v}
1, 3, {nan, v,b}


In this example A and B are the columns I used in the groupby. I'd like to add another column to this dataframe which is the number of elements in column C which are not ``nan. That is I want my dataframe to look like below



A, B, C, D
1, 2, {nan, v}, 1
1, 3, {nan, v,b}, 2


How can I do that?










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  • It is better upvote and accept to close the old question before you asking a new one, I notice , you have been asking a lot question with good answer posted but none of them had been accepted

    – Wen-Ben
    Nov 15 '18 at 15:53


















0















I have a dataframe in pandas and I'm using 'set' as an aggregate function in a groupby and I create the following dataframe



A, B, C
1, 2, {nan, v}
1, 3, {nan, v,b}


In this example A and B are the columns I used in the groupby. I'd like to add another column to this dataframe which is the number of elements in column C which are not ``nan. That is I want my dataframe to look like below



A, B, C, D
1, 2, {nan, v}, 1
1, 3, {nan, v,b}, 2


How can I do that?










share|improve this question























  • It is better upvote and accept to close the old question before you asking a new one, I notice , you have been asking a lot question with good answer posted but none of them had been accepted

    – Wen-Ben
    Nov 15 '18 at 15:53
















0












0








0








I have a dataframe in pandas and I'm using 'set' as an aggregate function in a groupby and I create the following dataframe



A, B, C
1, 2, {nan, v}
1, 3, {nan, v,b}


In this example A and B are the columns I used in the groupby. I'd like to add another column to this dataframe which is the number of elements in column C which are not ``nan. That is I want my dataframe to look like below



A, B, C, D
1, 2, {nan, v}, 1
1, 3, {nan, v,b}, 2


How can I do that?










share|improve this question














I have a dataframe in pandas and I'm using 'set' as an aggregate function in a groupby and I create the following dataframe



A, B, C
1, 2, {nan, v}
1, 3, {nan, v,b}


In this example A and B are the columns I used in the groupby. I'd like to add another column to this dataframe which is the number of elements in column C which are not ``nan. That is I want my dataframe to look like below



A, B, C, D
1, 2, {nan, v}, 1
1, 3, {nan, v,b}, 2


How can I do that?







pandas pandas-groupby






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asked Nov 15 '18 at 15:27









H.Z.H.Z.

1,83354394




1,83354394













  • It is better upvote and accept to close the old question before you asking a new one, I notice , you have been asking a lot question with good answer posted but none of them had been accepted

    – Wen-Ben
    Nov 15 '18 at 15:53





















  • It is better upvote and accept to close the old question before you asking a new one, I notice , you have been asking a lot question with good answer posted but none of them had been accepted

    – Wen-Ben
    Nov 15 '18 at 15:53



















It is better upvote and accept to close the old question before you asking a new one, I notice , you have been asking a lot question with good answer posted but none of them had been accepted

– Wen-Ben
Nov 15 '18 at 15:53







It is better upvote and accept to close the old question before you asking a new one, I notice , you have been asking a lot question with good answer posted but none of them had been accepted

– Wen-Ben
Nov 15 '18 at 15:53














1 Answer
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Using



df['D']=pd.DataFrame(df.C.tolist(),index=df.index).notnull().sum(axis=1)





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    1 Answer
    1






    active

    oldest

    votes








    1 Answer
    1






    active

    oldest

    votes









    active

    oldest

    votes






    active

    oldest

    votes









    1














    Using



    df['D']=pd.DataFrame(df.C.tolist(),index=df.index).notnull().sum(axis=1)





    share|improve this answer




























      1














      Using



      df['D']=pd.DataFrame(df.C.tolist(),index=df.index).notnull().sum(axis=1)





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        1












        1








        1







        Using



        df['D']=pd.DataFrame(df.C.tolist(),index=df.index).notnull().sum(axis=1)





        share|improve this answer













        Using



        df['D']=pd.DataFrame(df.C.tolist(),index=df.index).notnull().sum(axis=1)






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        answered Nov 15 '18 at 15:39









        Wen-BenWen-Ben

        117k83469




        117k83469
































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