It looks like EPD's version of matplotlib wasn't built with the _tkagg
extension (it is an optional component). This e-mail thread  seems
to suggest that it has gone in and out of EPD (though it's supposed to
be back in 6.0). Of course, I don't usually run EPD or Windows myself,
so I'm completely guessing, and am not trying to point fingers at the
hard working guys at Enthought.
However, you may want to ask this question in an EPD support forum to
see what they say.
Bradley Minch wrote:
> Hi everyone,
> I would like to develop a Tkinter GUI application for a course that I am teaching this semester that has an embedded matplotlib plot. I was hoping to have this application work with both the Mac OS X and Windows versions of Enthought Python Distribution v. 6.0.0. As a starting point, I was going to try the user interface examples, embedding_in_tk.py and embedding_in_tk2.py, on the matplotlib website. I have changed my default backend from WXAgg to TkAgg in my matplotlibrc file. With the Mac OS X version of EPD 6.0.0, the examples seem to work just fine. However, with the Windows version, I get the following import error:
> C:\Documents and Settings\bminch\Desktop>python embedding_in_tk2.py
> Traceback (most recent call last):
> File "embedding_in_tk2.py", line 6, in <module>
> from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg, NavigationT
> File "C:\Python26\lib\site-packages\matplotlib\backends\backend_tkagg.py", lin
> e 8, in <module>
> import tkagg # Paint image to Tk photo blitter extension
> File "C:\Python26\lib\site-packages\matplotlib\backends\tkagg.py", line 1, in
> import _tkagg
> ImportError: No module named _tkagg
> C:\Documents and Settings\bminch\Desktop>
> The same thing happens when I invoke ipython with the -pylab option, although with a traceback that is a bit longer. At the bottom of it is the same import error, "No module named _tkagg."
> Has anyone experienced similar problems with the TkAgg backend under the Windows version of EPD 6.0.0? Can anyone suggest how to fix the problem?
> Brad Minch.
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