Exception Upon Pivoting an Empty DataFrame
from pandas import DataFrame
df = DataFrame({},columns=['time','item','value'])
df.pivot('time','item','value')

pandas\core\frame.pyc in pivot(self, index, columns, values)
   1953         """
   1954         from pandas.core.reshape import pivot
-> 1955         return pivot(self, index=index, columns=columns, values=values)
   1956
   1957     def stack(self, level=-1, dropna=True):

pandas\core\reshape.pyc in pivot(self, index, columns, values)
    220         stacked = stacked.sortlevel(level=0)
    221
--> 222     unstacked = stacked.unstack()
    223     if values is not None:
    224         unstacked.columns = unstacked.columns.droplevel(0)

pandas\core\frame.pyc in unstack(self, level)
   2017             return result
   2018         else:
-> 2019             return unstack(self, level)
   2020
   2021     def delevel(self):

pandas\core\reshape.pyc in unstack(obj, level)
    289     unstacker = _Unstacker(obj.values, obj.index, level=level,
    290                            value_columns=columns)
--> 291     return unstacker.get_result()
    292
    293 def stack(frame, level=-1, dropna=True):

pandas\core\reshape.pyc in get_result(self)
    120
    121         # filter out missing levels

--> 122         values = values[:, mask]
    123         columns = columns[mask]
    124

IndexError: invalid index
