Re: [Matplotlib-users] Fatal Python error: deallocating None

[John H. <jd...@gm...>]

On 4/13/07, John Morgan <mo...@gm...> wrote:
> I'm using matplotlib with Python 2.4.4 to make scatter plots of a
> reasonably large dataset. Specifically about 200 plots with around
> 3224 points each. Unfortunately after about 30-40 plots, python
> invariably crashes with the error:
>

Could you produce a piece of freestanding code that we can run that
reproduces the error so we can try and debug it.  Unfortunately, there
is nothing obviously wrong with your code, which means it is likely to
be a bug on our side.

Also, please report your versions of matplotlib and numpy, etc.  One
good way to do this is to create a simple test script and run it with

> python test.py --verbose-helpful

and paste the output here.

To kickstart the process, here is a script that makes 500 figures with
a similar number of points that *does not crash* on my system.  If you
are generating figures in batch, make sure you are running in a image
backend like Agg (for PNG) or PS (for postscript) ....

import matplotlib
matplotlib.use('Agg')
import numpy
import pylab
N = 3224
ind = numpy.arange(float(N))
for i in range(500):
    fig = pylab.figure()
    ax = fig.add_subplot(111)
    ax.plot(ind, numpy.random.rand(N), ',')
    ax.plot(ind, numpy.random.rand(N), ',')
    ax.plot(ind, numpy.random.rand(N), ',')
    ax.plot(ind, numpy.random.rand(N), ',')
    ax.set_title('Baseline %d'%i)
    fig.savefig('TimeSeries %d'%i)
    pylab.close()
    print 'printing baseline ', i



Thanks,
JDH

JDH