matplotlib Code

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<h2>Using matplotlib interactively</h2>

matplotlib can be used interactively from the python shell to create
figures and modify their properties, as you can do in matlab, maple or
mathematica.  Unfortunately, due to the 'mainloop' cycle of GUI
toolkits, it is not yet possible to use matplotlib from an arbitrary
python shell.  Instead, there are custom solutions depending on the
GUI environment in which you use matplotlib.  If you know of solutions
bettern than the ones presented here, please contact me -
 @myemail@.<p>

<h3>WX</h3>

<h3>GTK</h3>
There are two interactive shells provided with matplotlib for GTK,
which are in the examples dir of the src distribution (<a
href=examples/interactive.py>interactive.py</a> and <a
href=examples/interactive2.py>interactive2.py</a>).<p>


<tt>interactive2.py</tt> will work with any pygtk 1.99.16 or
later, regardless of whether threading was built in or not.
<tt>interactive.py</tt> requires an interpreter with threading an
so requires a bit more work.  There are relative strengths of both
these interpreters and neither is perfect.  For example,
interactive2.py is easier to set up since it doesn't require
threading, and looks nicer, but interactive.py better handles cutting
and pasting of code blocks from an editor into the interpreter.<p>


Note, if you use the matplotlib interactive interpreter, you do not
need to import any of the matplotlib.matlab, Numeric or MLab symbols,
as this is done automatically by the interpreter.  Thus you can issue
plot commands immediately

<pre>
examples> ./interactive2.py
>>> plot([1,2,3])
</pre>

<h2>pygtk with threading</h2>

The rest of this page details how to get pygtk setup with threading if
you want to use interactive.py (interactive2.py doesn't require it).
The core functionality of this interpreter was provided by <a
href=http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/65109>Brian
McErlean and John Finlay</a>.<p>


<h3>WIN32 Users</h3>

  You will need pygtk compiled for threading.  The lastest version for
  windows at Cedirc's website, pygtk-2.0.0 has threading built in
  automatically.  If for some reason, you need an older version, a
  windows installer for pygtk-1.99.16 with threading is available at
  <a
  href=http://nitace.bsd.uchicago.edu:8080/Wikis/Leo/Python/win32/pygtk-1.99.16.threading.win32-py2.2.exe>pygtk-1.99.16
  with threading</a>.<p>


  I have seen reports of threading difficulties with pygtk on win32,
  but haven't experienced them myself.  If you experience freezes or
  other strangeness, check the <a
  href=http://www.async.com.br/faq/pygtk/index.py?req=show&file=faq21.003.htp>pygtk
  FAQ entry</a>.<p>


<h3>Linux/UNIX Users</h3>

  To compile pygtk with threading, you need to build with<p>

  <pre>
  > python setup.py build --enable-threading
  > python setup.py install
  </pre>

  If after this install, threading still is not working for you, you
  may want to try a clean install using configure.  See below.<p>
  
<h3>Testing threading</h3>

  To test whether this install worked, try running this script<p>

  <pre>
    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()
  </pre>


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

<h3>Testing with matplotlib</h3>

  You should be able to make a simple plot with<p>

  <pre>
  > cd examples
  > ./interactive.py
  >>> plot([1,2,3])
  </pre>


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