Group By

df.group_by('col').mean()
df.group_by(['col1', 'col2']).mean()Multi-Index
# how to index a multi level group
grouped.loc[('catagory', 'catagory')]
# only shows groups with value 'catagory' on col 'col'
grouped.xs(key='catagory', level='col')
grouped.swaplevel()
grouped.sort_index(level='col', ascending=True)