in HTSeq example, pyplot

[hibachings2013]

Hi All,

I am trying to run HTSeq with my data set and am using a script shown in HTSeq web site as a simple example. but just got error message in pyplot function in python. i am a very beginner of python.
is there anyone who ran this example successfully and can advise me what i am missing now here?


Thanx a lot in advance!

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>>> from matplotlib import pyplot
>>> #import _tkagg
... #import Tkinter as Tk
...
>>> pyplot.plot(qualsum/nreads)
[<matplotlib.lines.Line2D object at 0x2f69cd0>]
>>> pyplot.show()
Exception in Tkinter callback
Traceback (most recent call last):
File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-tk/Tkinter.py", line 1410, in __call__
return self.func(*args)
File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/matplotlib/backends/backend_tkagg.py", line 245, in resize
self.show()
File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/matplotlib/backends/backend_tkagg.py", line 249, in draw
tkagg.blit(self._tkphoto, self.renderer._renderer, colormode=2)
File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/matplotlib/backends/tkagg.py", line 19, in blit
tk.call("PyAggImagePhoto", photoimage, id(aggimage), colormode, id(bbox_array))
TclError

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