Qt4Agg backend broken in matplotlib

[goyodiaz]

D:\>python
Python 2.5.2 (r252:60911, Feb 21 2008, 13:11:45) [MSC v.1310 32 bit (Intel)] on
win32
Type "help", "copyright", "credits" or "license" for more information.
>>> import matplotlib as mpl
>>> mpl.use('Qt4Agg')
>>> import matplotlib.pyplot as plt
>>> plt.plot([1, 2])
[<matplotlib.lines.Line2D object at 0x0180FB90>]
>>> plt.show()
Traceback (most recent call last):
  File "D:\OSGeo4w\apps\Python25\lib\site-packages\matplotlib\backends\backend_q
t4.py", line 168, in resizeEvent
    self.draw()
  File "D:\OSGeo4w\apps\Python25\lib\site-packages\matplotlib\backends\backend_q
t4agg.py", line 130, in draw
    FigureCanvasAgg.draw(self)
  File "D:\OSGeo4w\apps\Python25\lib\site-packages\matplotlib\backends\backend_a
gg.py", line 313, in draw
    self.renderer = self.get_renderer()
  File "D:\OSGeo4w\apps\Python25\lib\site-packages\matplotlib\backends\backend_a
gg.py", line 319, in get_renderer
    try: self._lastKey, self.renderer
TypeError: 'sip.methoddescriptor' object is not callable
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "D:\OSGeo4w\apps\Python25\lib\site-packages\matplotlib\backends\backend_q
t4.py", line 69, in show
    figManager.canvas.draw()
  File "D:\OSGeo4w\apps\Python25\lib\site-packages\matplotlib\backends\backend_q
t4agg.py", line 130, in draw
    FigureCanvasAgg.draw(self)
  File "D:\OSGeo4w\apps\Python25\lib\site-packages\matplotlib\backends\backend_a
gg.py", line 313, in draw
    self.renderer = self.get_renderer()
  File "D:\OSGeo4w\apps\Python25\lib\site-packages\matplotlib\backends\backend_a
gg.py", line 319, in get_renderer
    try: self._lastKey, self.renderer
TypeError: 'sip.methoddescriptor' object is not callable
>>> Traceback (most recent call last):
  File "D:\OSGeo4w\apps\Python25\lib\site-packages\matplotlib\backends\backend_q
t4agg.py", line 83, in paintEvent
    FigureCanvasAgg.draw(self)
  File "D:\OSGeo4w\apps\Python25\lib\site-packages\matplotlib\backends\backend_a
gg.py", line 313, in draw
    self.renderer = self.get_renderer()
  File "D:\OSGeo4w\apps\Python25\lib\site-packages\matplotlib\backends\backend_a
gg.py", line 319, in get_renderer
    try: self._lastKey, self.renderer
TypeError: 'sip.methoddescriptor' object is not callable

The offending line is testing for attributes existence. The next line catches AttributeError but now a TypeError is raised. Catching TypeError in line 320 seems to solve this.

Before:

try: self._lastKey, self.renderer
except AttributeError: need_new_renderer = True
else:  need_new_renderer = (self._lastKey != key)

After

try: self._lastKey, self.renderer
except (AttributeError, TypeError): need_new_renderer = True
else:  need_new_renderer = (self._lastKey != key)

[willfurnass]

Looks like the following (apparently fixed in Python 2.5.3):

​http://www.mail-archive.com/pyqt@riverbankcomputing.com/msg23618.html

​http://bugs.python.org/issue4230

[jef]

fixed in matplotlib-0.99.0-2