Selecting rows from a Pandas dataframe with a compound (hierarchical) index

Question

I\'m suspicious that this is trivial, but I yet to discover the incantation that will let me select rows from a Pandas dataframe based on the values of a hierarchical key. S

Answer 1

Try using xs to be very precise:

In [5]: df.xs('a', level=0)
Out[5]: 
        value1  value2
group2                
c          1.1     7.1
c          2.0     8.0
d          3.0     9.0

In [6]: df.xs('c', level='group2')
Out[6]: 
        value1  value2
group1                
a          1.1     7.1
a          2.0     8.0