pandas: how to run a pivot with a multi-index?

Question

I would like to run a pivot on a pandas DataFrame, with the index being two columns, not one. For example, one field for the year, one for the month, an \'item\

Answer 1

I believe if you include item in your MultiIndex, then you can just unstack:

df.set_index(['year', 'month', 'item']).unstack(level=-1)

This yields:

                value      
item       item 1 item 2
year month              
2004 1         21    277
     2         43    244
     3         12    262
     4         80    201
     5         22    287
     6         52    284
     7         90    249
     8         14    229
     9         52    205
     10        76    207
     11        88    259
     12        90    200

It's a bit faster than using pivot_table, and about the same speed or slightly slower than using groupby.