Re: [Matplotlib-users] Trouble building matplotlib on Solaris 8

[John H. <jdh...@ac...>]

>>>>> "skip" == skip  <sk...@po...> writes:

    Skip> >>> plot([1,2,3,4])
    Skip> [<matplotlib.lines.Line2D instance at 0x8790d6c>]
    Skip> >>> show()

    Skip> (process:3261): GLib-GObject-CRITICAL **: gtype.c:2253: 
    Skip> initialization assertion failed, use g_type_init() prior to 
    Skip> this function
    Skip> Segmentation Fault (core dumped)

The problem here is that "show" starts the GUI mainloop when using a
GUI backend (GTKAgg is the default).  To use the GTK, WX, or Qt
backends from a shell, you need to use a shell that starts the GUI
mainloop in a separate thread (Tkinter is special in this regard, in
that it can be use from the shell with no special threading calls, so
if you need to use the standard python shell for interactive work, you
should use the TkAgg backend).  Also, you should not be using "show"
when working interactively from the shell.  This is discussed in more
detail at

  http://matplotlib.sourceforge.net/interactive.html

and 

  http://matplotlib.sourceforge.net/faq.html#SHOW

The recommended approach for using the GTK/WX/Qt backends
interactively from the shell is to use the ipython shell.  ipython is
an easy install (pure python) and in addition to lots of nice
interactive features, has matplotlib support.  Specifically, in the
pylab mode

  > ipython -pylab

it will read your matplotlibrc file, detect your backend, issue the
proper threading and timer/idle calls as needed for GTK, WX, Qt or Tk,
import the pylab namespace and wash your dishes

  http://ipython.scipy.org

Eg, you can do

> ipython -pylab
Python 2.4.1 (#2, Mar 30 2005, 21:51:10)
Type "copyright", "credits" or "license" for more information.

In [1]: hist(randn(10000), 100)

and your plot should appear automagically.

If for some reason ipython is not an option for you, and you need to
use a GTK backend from the shell, there is some template code in the
matplotlib examples directory showing how to write a custom shell with
the proper gtk threading calls.

JDH