IndexError When Ploting a Dataframe with Sliced columns using iloc
With the following, I can plot work, but I can not plot nowork. I can't see any clear difference between the two resulting dataframes. I also get the issue when trying to slice use .loc and range of labels.

``` python
work = mp_stats_unstack.xs(0, level='CPU', axis=1).iloc[:,[x for x in range(48,63)]]
nowork = mp_stats_unstack.xs(0, level='CPU', axis=1).iloc[:,48:63]
nowork
<class 'pandas.core.frame.DataFrame'>
Int64Index: 1848 entries, 1378842548 to 1378844396
Data columns (total 15 columns):
NMI/s    1848  non-null values
LOC/s    1848  non-null values
SPU/s    1848  non-null values
PMI/s    1848  non-null values
IWI/s    1848  non-null values
RTR/s    1848  non-null values
RES/s    1848  non-null values
CAL/s    1848  non-null values
TLB/s    1848  non-null values
TRM/s    1848  non-null values
THR/s    1848  non-null values
MCE/s    1848  non-null values
MCP/s    1848  non-null values
ERR/s    1848  non-null values
MIS/s    1848  non-null values
dtypes: float64(15)

work
<class 'pandas.core.frame.DataFrame'>
Int64Index: 1848 entries, 1378842548 to 1378844396
Data columns (total 15 columns):
NMI/s    1848  non-null values
LOC/s    1848  non-null values
SPU/s    1848  non-null values
PMI/s    1848  non-null values
IWI/s    1848  non-null values
RTR/s    1848  non-null values
RES/s    1848  non-null values
CAL/s    1848  non-null values
TLB/s    1848  non-null values
TRM/s    1848  non-null values
THR/s    1848  non-null values
MCE/s    1848  non-null values
MCP/s    1848  non-null values
ERR/s    1848  non-null values
MIS/s    1848  non-null values
dtypes: float64(15)

nowork.plot()
---------------------------------------------------------------------------
IndexError                                Traceback (most recent call last)
<ipython-input-482-b831b20208bb> in <module>()
----> 1 nowork.plot()

/usr/local/lib/python3.3/site-packages/pandas/tools/plotting.py in plot_frame(frame, x, y, subplots, sharex, sharey, use_index, figsize, grid, legend, rot, ax, style, title, xlim, ylim, logx, logy, xticks, yticks, kind, sort_columns, fontsize, secondary_y, **kwds)
   1634                      logy=logy, sort_columns=sort_columns,
   1635                      secondary_y=secondary_y, **kwds)
-> 1636     plot_obj.generate()
   1637     plot_obj.draw()
   1638     if subplots:

/usr/local/lib/python3.3/site-packages/pandas/tools/plotting.py in generate(self)
    852     def generate(self):
    853         self._args_adjust()
--> 854         self._compute_plot_data()
    855         self._setup_subplots()
    856         self._make_plot()

/usr/local/lib/python3.3/site-packages/pandas/tools/plotting.py in _compute_plot_data(self)
    925         try:
    926             # might be an ndframe
--> 927             numeric_data = self.data._get_numeric_data()
    928         except AttributeError:  # TODO: rm in 0.13 (series-inherit-ndframe)
    929             numeric_data = self.data

/usr/local/lib/python3.3/site-packages/pandas/core/frame.py in _get_numeric_data(self)
   5291 
   5292     def _get_numeric_data(self):
-> 5293         return self._constructor(self._data.get_numeric_data(), index=self.index, copy=False)
   5294 
   5295     def _get_bool_data(self):

/usr/local/lib/python3.3/site-packages/pandas/core/internals.py in get_numeric_data(self, copy, type_list, as_blocks)
   1398 
   1399         indexer = np.sort(np.concatenate([b.ref_locs for b in num_blocks]))
-> 1400         new_items = self.items.take(indexer)
   1401 
   1402         new_blocks = []

/usr/local/lib/python3.3/site-packages/pandas/core/index.py in take(self, indexer, axis)
    393         """
    394         indexer = com._ensure_platform_int(indexer)
--> 395         taken = self.view(np.ndarray).take(indexer)
    396         return self._constructor(taken, name=self.name)
    397 

IndexError: index 15 is out of bounds for axis 0 with size 15
```
