I was thinking about the first example in the tutorial. On windows, TkAgg is the default backend, at least for the precompiled windows version. If Idle is run with -n, the show() command must be omitted, or the window will not render. Interactive2.py will try to render the window and then hang, as will pycrust. I think the first thing a newbie to matplotlib wants to do is open their favorite shell interface and make sure they can reproduce the first example in the tutorial.
Darren S. Dale
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