FigureCanvasAgg'对象没有属性'invalidate'？python密谋

Question

我一直在关注'python进行数据分析'.在pg.345,你得到这个代码来绘制各种股票的回报.但是,绘图功能对我不起作用.我得到了FigureCanvasAgg'对象没有属性'invalidate'？

names = ['AAPL','MSFT', 'DELL', 'MS', 'BAC', 'C'] #goog and SF did not work
def get_px(stock, start, end):
    return web.get_data_yahoo(stock, start, end)['Adj Close']
px = pd.DataFrame({n: get_px(n, '1/1/2009', '6/1/2012') for n in names})

#fillna method pad uses last valid observation to fill
px = px.asfreq('B').fillna(method='pad')
rets = px.pct_change()
df2 = ((1 + rets).cumprod() - 1)

df2.ix[0] = 1

df2.plot()

更新:完全追溯

---------------------------------------------------------------------------
AttributeError                            Traceback (most recent call last)
<ipython-input-122-df192c0432be> in <module>()
      6 df2.ix[0] = 1
      7 
----> 8 df2.plot()

//anaconda/lib/python2.7/site-packages/pandas/tools/plotting.pyc 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:

//anaconda/lib/python2.7/site-packages/pandas/tools/plotting.pyc in generate(self)
    854         self._compute_plot_data()
    855         self._setup_subplots()
--> 856         self._make_plot()
    857         self._post_plot_logic()
    858         self._adorn_subplots()

//anaconda/lib/python2.7/site-packages/pandas/tools/plotting.pyc in _make_plot(self)
   1238         if not self.x_compat and self.use_index and self._use_dynamic_x():
   1239             data = self._maybe_convert_index(self.data)
-> 1240             self._make_ts_plot(data, **self.kwds)
   1241         else:
   1242             lines = []

//anaconda/lib/python2.7/site-packages/pandas/tools/plotting.pyc in _make_ts_plot(self, data, **kwargs)
   1319                 self._maybe_add_color(colors, kwds, style, i)
   1320 
-> 1321                 _plot(data[col], i, ax, label, style, **kwds)
   1322 
   1323         self._make_legend(lines, labels)

//anaconda/lib/python2.7/site-packages/pandas/tools/plotting.pyc in _plot(data, col_num, ax, label, style, **kwds)
   1293         def _plot(data, col_num, ax, label, style, **kwds):
   1294             newlines = tsplot(data, plotf, ax=ax, label=label,
-> 1295                                 style=style, **kwds)
   1296             ax.grid(self.grid)
   1297             lines.append(newlines[0])

//anaconda/lib/python2.7/site-packages/pandas/tseries/plotting.pyc in tsplot(series, plotf, **kwargs)
     79 
     80     # set date formatter, locators and rescale limits
---> 81     format_dateaxis(ax, ax.freq)
     82     left, right = _get_xlim(ax.get_lines())
     83     ax.set_xlim(left, right)

//anaconda/lib/python2.7/site-packages/pandas/tseries/plotting.pyc in format_dateaxis(subplot, freq)
    258     subplot.xaxis.set_major_formatter(majformatter)
    259     subplot.xaxis.set_minor_formatter(minformatter)
--> 260     pylab.draw_if_interactive()

//anaconda/lib/python2.7/site-packages/IPython/utils/decorators.pyc in wrapper(*args, **kw)
     41     def wrapper(*args,**kw):
     42         wrapper.called = False
---> 43         out = func(*args,**kw)
     44         wrapper.called = True
     45         return out

//anaconda/lib/python2.7/site-packages/matplotlib/backends/backend_macosx.pyc in draw_if_interactive()
    227         figManager =  Gcf.get_active()
    228         if figManager is not None:
--> 229             figManager.canvas.invalidate()
    230 
    231 

AttributeError: 'FigureCanvasAgg' object has no attribute 'invalidate'

Answer 1

我发现这个错误是由于以下因素的组合:

• 使用pandas绘图与系列或数据框成员方法
• 用日期索引绘图
• %matplotlib inline在ipython中使用魔法
• 在matplotlib魔法之前导入pylab模块

因此,ipython笔记本中新启动的内核将失败:

# fails 
import matplotlib.pylab
%matplotlib inline

import pandas
ser = pandas.Series(range(10), pandas.date_range(end='2014-01-01', periods=10))
ser.plot()

解决这个问题的最好方法是将魔法移到顶端:

# succeeds
%matplotlib inline # moved up
import matplotlib.pylab

import pandas
ser = pandas.Series(range(10), pandas.date_range(end='2014-01-01', periods=10))
ser.plot()

但是,如果将系列传递给matplotlib绘图方法,不使用日期索引,或者只是不导入matplotlib.pylab模块,问题也会消失.

Answer 2

不是答案，但我不知道如何将代码块放在注释中:)

所以我提出这个问题是因为我的 Mac 上也发生了完全相同的事情

/Users/briford/myPVE/workbench/lib/python2.7/site-packages/matplotlib/backends/backend_macosx.pyc in draw_if_interactive()
    227         figManager =  Gcf.get_active()
    228         if figManager is not None:
--> 229             figManager.canvas.invalidate()
    230 
AttributeError: 'FigureCanvasAgg' object has no attribute 'invalidate'

无论如何，我知道这并不令人满意，但只需关闭我的 ipython 笔记本服务并重新启动就可以清除它......耸耸肩......