matplotlib

I tried your simple example and I have indeed the following crash when I 
tried to print preview :
---------------------------------------------------------------------------
NotImplementedError                       Traceback (most recent call last)

/usr/lib/python2.5/site-packages/matplotlib/backends/backend_wx.py in 
OnPrintPage(self, page)
   2057
   2058         renderer  = RendererWx(self.canvas.bitmap, 
self.canvas.figure.dpi)
-> 2059         self.canvas.figure.draw(renderer)
   2060         self.canvas.bitmap.SetWidth(  
int(self.canvas.bitmap.GetWidth() * vscale))
   2061         self.canvas.bitmap.SetHeight( 
int(self.canvas.bitmap.GetHeight()* vscale))

/usr/lib/python2.5/site-packages/matplotlib/figure.py in draw(self, 
renderer)
    610
    611         # render the axes
--> 612         for a in self.axes: a.draw(renderer)
    613
    614         # render the figure text

/usr/lib/python2.5/site-packages/matplotlib/axes.py in draw(self, 
renderer, inframe)
   1340
   1341         for zorder, i, a in dsu:
-> 1342             a.draw(renderer)
   1343
   1344         self.transData.thaw()  # release the lazy objects

/usr/lib/python2.5/site-packages/matplotlib/axis.py in draw(self, 
renderer, *args, **kwargs)
    591             tick.set_label1(label)
    592             tick.set_label2(label)
--> 593             tick.draw(renderer)
    594             if tick.label1On and tick.label1.get_visible():
    595                 extent = tick.label1.get_window_extent(renderer)

/usr/lib/python2.5/site-packages/matplotlib/axis.py in draw(self, renderer)
    168             if self.tick2On: self.tick2line.draw(renderer)
    169
--> 170         if self.label1On: self.label1.draw(renderer)
    171         if self.label2On: self.label2.draw(renderer)
    172

/usr/lib/python2.5/site-packages/matplotlib/text.py in draw(self, renderer)
    773     def draw(self, renderer):
    774         self.update_coords(renderer)
--> 775         Text.draw(self, renderer)
    776         if self.get_dashlength() > 0.0:
    777             self.dashline.draw(renderer)

/usr/lib/python2.5/site-packages/matplotlib/text.py in draw(self, renderer)
    325
    326                 renderer.draw_tex(gc, x, y, line,
--> 327                                   self._fontproperties, angle)
    328             return
    329

/usr/lib/python2.5/site-packages/matplotlib/backend_bases.py in 
draw_tex(self, gc, x, y, s, prop, angle, ismath)
    381
    382     def draw_tex(self, gc, x, y, s, prop, angle, ismath='TeX!'):
--> 383         raise NotImplementedError
    384
    385     def draw_text(self, gc, x, y, s, prop, angle, ismath=False):

NotImplementedError:


Not familiar enough with all this to be of much help here...
Johann