Python Pandas: Check If Items From List Is In Df Index

I have a dataframe: data = {'year': [2010, 2011, 2012, 2011, 2012, 2010, 2011, 2012], 'team': ['Bears', 'Bears', 'Bears', 'Packers', 'Packers', 'Lions', 'Lions', 'Lions'],

Solution 1:

The reason you saw ['b','c'] in your first attempt is that what is returned from the inner isin is a boolean index of [False, True, True] which you're applying to the df from the beginning, you need to reapply it again to the last 3 rows:

In [21]:

fixed_cats = ['d','g','ssa']
football[-len(fixed_cats):][football.index[-len(fixed_cats):].isin(fixed_cats)]
Out[21]:
     year   team wins losses
g    2011  Lions  20%6%
ssa  2012  Lions   4%12%

In [22]:

football.index[-len(fixed_cats):].isin(fixed_cats)
Out[22]:
array([False,  True,  True], dtype=bool)

So the above boolean index needs to be applied to the last 3 rows rather to the entire df again which is what you are doing