Re: [Matplotlib-users] Is really matplotlib this slooow for displaying images ? (sorry again)

[Eric E. <ems...@ob...>]

Test done and this is correct, here are the sets of timing :
first line is without ''mynorm'', second is with ''mynorm''.
time python test.py --Numeric -dTkAgg
10.432u 1.663s 0:12.37 97.7%    0+0k 0+0io 0pf+0w
7.258u 1.302s 0:08.64 98.9%     0+0k 0+0io 0pf+0w

time python test.py --Numeric -dGTKAgg
5.209u 0.845s 0:06.10 99.0%     0+0k 0+0io 0pf+0w
4.226u 0.700s 0:04.98 98.7%     0+0k 0+0io 0pf+0w

time python test.py --numarray -dTkAgg
16.391u 1.036s 0:17.96 96.9%    0+0k 0+0io 0pf+0w
5.690u 0.829s 0:06.85 95.0%     0+0k 0+0io 0pf+0w

time python test.py --numarray -dGTKAgg
8.225u 0.546s 0:08.96 97.7%     0+0k 0+0io 0pf+0w
3.363u 0.445s 0:03.86 98.4%     0+0k 0+0io 0pf+0w

Another factor of 10 and you are faster than Midas.. :-)

Eric

John Hunter wrote:

>>>>>>"John" == John Hunter <jdh...@ac...> writes:
>>>>>>            
>>>>>>
>
>    John> I'll spend some time with the profiler looking for some low
>    John> hanging fruit.
>
>God bless the profiler.  It turns out over half of the time to display
>this image is spent in the normalizer, which takes image data in an
>arbitrary scale and maps into the unit interval
>
>  http://matplotlib.sourceforge.net/matplotlib.colors.html#normalize
>
>The normalizer handles a lot of special cases that you may not need.
>In fact, your data may already be normalized.  So you can write a
>custom normalizer
>
>from pylab import *
>
>def mynorm(X):  # do nothing, it's already normalized
>    return X
>
>ion()
>
>rc('figure', figsize=(13,12))
>X = rand(1600,1600)
>figimage(X, cmap=cm.hot, norm=mynorm)
>
>
>This change alone gives me more than a 2x speedup.  So with GTKAgg + a
>custom normalizer (in this case a do nothing normalizer) you'll be
>running 4-5 times faster than you were before, me thinks.
>
>peds-pc311:~/python/projects/matplotlib> time python ~/test.py --numarray
>1.650u 0.450s 0:02.13 98.5%     0+0k 0+0io 4746pf+0w
>
>I'll keep digging through the profiler...
>
>JDH
>
>  
>

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