Multi Index Sorting in Pandas

When sorting by a MultiIndex you need to contain the tuple describing the column inside a list*:

In [11]: df.sort_values([('Group1', 'C')], ascending=False)
Out[11]: 
  Group1       Group2      
       A  B  C      A  B  C
2      5  6  9      1  0  0
1      1  0  3      2  5  7
3      7  0  2      0  3  5

* so as not to confuse pandas into thinking you want to sort first by Group1 then by C.


Note: Originally used .sort since deprecated then removed in 0.20, in favor of .sort_values.