How to convert index of a pandas dataframe into a column?

Question

This seems rather obvious, but I can\'t seem to figure out how to convert an index of data frame to a column?

For example:

df=
        gi       ptt_l         


        

Answer 1

For MultiIndex you can extract its subindex using

df['si_name'] = R.index.get_level_values('si_name') 

where si_name is the name of the subindex.