Re: [Matplotlib-users] segfaults in ipython

[Charles M. <cm...@in...>]

FYI, turning off pprint gets rid of the error.  Will look into it more.

Fernando Perez wrote:
> John Hunter wrote:
> 
>> but in ipython I get the segfault
>>
>>     peds-pc311:~> ipython
>>     Python 2.4.1 (#2, Mar 30 2005, 21:51:10)
>>     Type "copyright", "credits" or "license" for more information.
>>
>>     IPython 0.6.16_cvs -- An enhanced Interactive Python.
>>     ?       -> Introduction to IPython's features.
>>     %magic  -> Information about IPython's 'magic' % functions.
>>     help    -> Python's own help system.
>>     object? -> Details about 'object'. ?object also works, ?? prints 
>> more.
>>
>>     In [1]: from matplotlib.transforms import unit_bbox
>>
>>     In [2]: b = unit_bbox()
>>
>>     In [3]: b
>>     Segmentation fault
> 
> 
> This one is going to be hard to track, since I can't reproduce it on my 
> system (Fedora 3):
> 
> planck[~]> ip
> Python 2.3.4 (#1, Feb  2 2005, 12:11:53)
> Type "copyright", "credits" or "license" for more information.
> 
> IPython 0.6.16_svn -- An enhanced Interactive Python.
> ?       -> Introduction to IPython's features.
> %magic  -> Information about IPython's 'magic' % functions.
> help    -> Python's own help system.
> object? -> Details about 'object'. ?object also works, ?? prints more.
> 
> In [1]: from matplotlib.transforms import unit_bbox
> 
> In [2]: b = unit_bbox()
> 
> In [3]: b
> Out[3]: <Bbox object at 0x965d6d4>
> 
> In [4]:
> 
> In [4]:
> planck[~]> pylab
> 
> In [1]: from matplotlib.transforms import unit_bbox
> 
> In [2]: b = unit_bbox()
> 
> In [3]: b
> Out[3]: <Bbox object at 0x893866c>
> 
> So neither plain ipython nor 'ipython -pylab' show me any sign of 
> trouble here.
> 
> I'm afraid we'll have to debug this one by proxy, since I can't see any 
> problem here.  The code which is executed when output is to be printed 
> is the __call__ method of the CachedOutput object.  Look around line 476 
> in IPython/Prompts.py.  Adding some print/debug statements to that 
> function might shed some light.
> 
> One thing you could try is toggling %Pprint back and forth.  This is the 
> pretty printer used by ipython, which is part of the stdlib (module 
> pprint). It might be triggering some problem in the underlying pycxx 
> objects.
> 
> Cheers,
> 
> f