[SciPy-user] matplotlib slow, biggles problem as well

John Hunter jdhunter at ace.bsd.uchicago.edu
Fri Sep 3 13:26:20 CDT 2004


>>>>> "David" == David Grant <david.grant at telus.net> writes:

    David> By the way, my problem is that I was using matplotlib, but
    David> when trying to plot a 300 point array, it chokes up.  I
    David> could downsample it, but why should I have to?  Mathematica
    David> doesn't have problems plotting arrays like this.
    David> matpoltlib doesn't crash necessarily, just goes exremely
    David> slow.  I was using plot(V,'ro').  Maybe I need to configure
    David> some options?  Or maybe it's just an inherent problem with
    David> tk or gtk or whatever.  Is there another plotting program I
    David> could try which would work for sure?

I routinely do 512x512 arrays with imshow in matplotlib on linux and
win32 with no performance problems on a modern p4. For 2D arrays,
imshow is much faster than pcolor for large arrays.  See the
image_demo* examples at http://matplotlib.sf.net/examples

For 1D arrays with plot and scatter, my system handles 20,000-50,000
(and larger) length arrays efficiently (order of 1 second to plot).
If you are having trouble with 300 point arrays, something is probably
wrong with your computer or matplotlib setup.

Make sure you read the FAQ http://matplotlib.sf.net/faq.html#SLOW
which explains the most common configuration problems - the main
problem comes from trying to use numarray with a matplotlib compiled
for numeric, and vice-versa.

If you keep having troubles, please post a script, your platform info,
your python / matplotlib / numeric version info to the matplotlib
list.

Cheers,
JDH



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