To use matplotlib interactively from the prompt, you need a special
interpreter that doesn't enter the gtk mainloop.  One is provided in
examples/interactive.py.  The coew functionality of this interpreter
was provided by Brian McErlean and John Finlay.  See the header for
more info.

This will only work if you have pygtk compiled with threading.  See
instrubtions below.

WIN32 Users

  I haven't tested the interactive shell on win32.  It is apparently
  possible, but not easy, to get threading to work on win32.  See
  http://www.async.com.br/faq/pygtk/index.py?req=show&file=faq21.003.htp

LINUX/UNIX Users:

  To compile pygtk with threading, I recommend you make a backup of your
  existing pygtk install tree and completely remove it

  eg 
    > cd /your/path/to/python/site-packages
    > cp -a gtk-2.0 /some/backup/dir
    > rm -rf gtk-2.0

  This is because I have found that recompiling pygtk with threads on top
  of an existing installation w/o threads does not enable threads.  Your
  milage may vary.

  Then from a clean pygtk src tree

   > ./configure --enable-thread  # and any other flags
   > make install

TESTING threading

  To test whether this install worked, try running this script

    import pygtk
    pygtk.require('2.0')
    import gtk

    import threading, time

    def func():
      n = 0
      while 1:
        print n
        n += 1
        time.sleep(0.1)

    gtk.threads_init()
    threading.Thread(target=func).start()
    gtk.mainloop()



  If it spits numbers back at you, you're golden.

TESTING with matplotlib

  You should be able to make a simple plot with

  > cd examples
  > ./interactive.py
  Welcome to matplotlib.

      help(matlab)   -- shows a list of all matlab compatible commands provided
      help(plotting) -- shows a list of plot specific commands

  >> plot([1,2,3])