How to pick specific columns Pandas dataframe when checking against NaN

Question

I have a pandas dataframe in Python that looks something like

       AccountID_x    AccountId  AmountCD_x  AmountDOC_x  AmountDoc_x  
1              NaN  4001001         


        

Answer 1

Try this:

df['new_column'] = df.apply(lambda x: x['AccountId'] if pd.isnull(x['AccountID_x']) else x['AccountID_x'], axis=1)