import pandas as pdimport numpy as npimport matplotlib.pyplot as plt# create sample dataframe with preset dates and values columnsdates = np.arange('2005-02', '2005-03', dtype='datetime64[D]')values = np.sin(np.array(range(len(dates))))df = pd.DataFrame({'dates': dates, 'values': values})# matplotlib figure + two subplots for comparisonfig, axes = plt.subplots(1, 2)# create two dataframes for comparison - one with all indices, including 0, and one with only odd indiceswith_zero_index = df.copy()without_zero_index = df[np.array(df.index) % 2 == 1].copy()# plot both - note how second plot fails without a 0 indexaxes[0].plot(with_zero_index['dates'], with_zero_index['values'])axes[1].plot(without_zero_index['dates'], without_zero_index['values'])

KeyError                                  Traceback (most recent call last)<ipython-input-29-28e878247c17> in <module>()     17 # plot both - note how second plot fails without a 0 index     18 axes[0].plot(with_zero_index['dates'], with_zero_index['values'])---> 19 axes[1].plot(without_zero_index['dates'], without_zero_index['values'])/home/jim/arcemweb/venv/local/lib/python2.7/site-packages/matplotlib/__init__.pyc in inner(ax, *args, **kwargs)   1809                     warnings.warn(msg % (label_namer, func.__name__),   1810                                   RuntimeWarning, stacklevel=2)-> 1811             return func(ax, *args, **kwargs)   1812         pre_doc = inner.__doc__   1813         if pre_doc is None:/home/jim/arcemweb/venv/local/lib/python2.7/site-packages/matplotlib/axes/_axes.pyc in plot(self, *args, **kwargs)   1425             kwargs['color'] = c   1426 -> 1427         for line in self._get_lines(*args, **kwargs):   1428             self.add_line(line)   1429             lines.append(line)/home/jim/arcemweb/venv/local/lib/python2.7/site-packages/matplotlib/axes/_base.pyc in _grab_next_args(self, *args, **kwargs)    384                 return    385             if len(remaining) <= 3:--> 386                 for seg in self._plot_args(remaining, kwargs):    387                     yield seg    388                 return/home/jim/arcemweb/venv/local/lib/python2.7/site-packages/matplotlib/axes/_base.pyc in _plot_args(self, tup, kwargs)    362             x, y = index_of(tup[-1])    363 --> 364         x, y = self._xy_from_xy(x, y)    365     366         if self.command == 'plot':/home/jim/arcemweb/venv/local/lib/python2.7/site-packages/matplotlib/axes/_base.pyc in _xy_from_xy(self, x, y)    195     def _xy_from_xy(self, x, y):    196         if self.axes.xaxis is not None and self.axes.yaxis is not None:--> 197             bx = self.axes.xaxis.update_units(x)    198             by = self.axes.yaxis.update_units(y)    199 /home/jim/arcemweb/venv/local/lib/python2.7/site-packages/matplotlib/axis.pyc in update_units(self, data)   1387         neednew = self.converter != converter   1388         self.converter = converter-> 1389         default = self.converter.default_units(data, self)   1390         if default is not None and self.units is None:   1391             self.set_units(default)/home/jim/arcemweb/venv/local/lib/python2.7/site-packages/matplotlib/dates.pyc in default_units(x, axis)   1562    1563         try:-> 1564             x = x[0]   1565         except (TypeError, IndexError):   1566             pass/home/jim/arcemweb/venv/local/lib/python2.7/site-packages/pandas/core/series.pyc in __getitem__(self, key)    519     def __getitem__(self, key):    520         try:--> 521             result = self.index.get_value(self, key)    522     523             if not np.isscalar(result):/home/jim/arcemweb/venv/local/lib/python2.7/site-packages/pandas/core/index.pyc in get_value(self, series, key)   1593    1594         try:-> 1595             return self._engine.get_value(s, k)   1596         except KeyError as e1:   1597             if len(self) > 0 and self.inferred_type in ['integer','boolean']:pandas/index.pyx in pandas.index.IndexEngine.get_value (pandas/index.c:3113)()pandas/index.pyx in pandas.index.IndexEngine.get_value (pandas/index.c:2844)()pandas/index.pyx in pandas.index.IndexEngine.get_loc (pandas/index.c:3704)()pandas/hashtable.pyx in pandas.hashtable.Int64HashTable.get_item (pandas/hashtable.c:7224)()pandas/hashtable.pyx in pandas.hashtable.Int64HashTable.get_item (pandas/hashtable.c:7162)()KeyError: 0