Python Pandas sorting after groupby and aggregate

Question

I am trying to sort data (Pandas) after grouping and aggregating and I am stuck. My data:

data = {\'from_year\': [2010, 2011, 2012, 2011, 2012, 2010, 2011, 2012]         


        

Answer 1

You can use sort_values, but first reset_index and then set_index:

#simplier aggregation
days_off_yearly = persons.groupby(["from_year", "name"])['out_days'].sum()
print(days_off_yearly)
from_year  name 
2010       John     17
2011       John     15
           John1    18
2012       John     10
           John4    11
           John6     4
Name: out_days, dtype: int64

print (days_off_yearly.reset_index()
                      .sort_values(['from_year','out_days'],ascending=False)
                      .set_index(['from_year','name']))
                 out_days
from_year name           
2012      John4        11
          John         10
          John6         4
2011      John1        18
          John         15
2010      John         17