[wxPython-users] Re: Draw method in PlotCanvas class for a number of points (>80,000) takes too much time

[Christopher Barker]

jmf wrote:
> You know, finding a bottleneck and improving speed can be quite
> a complicate task.

It sure can. Add that I mostly use Linux, and X-windows is asynchronous 
-- it's really a trick!

> If I attempt to compare the speed
> of my modules with numpy, one get sometimes good suprises.
> 
> Inverting 1000 times a 3x3 matrix with my module: 0.48 second
> Inverting 1000 times a 3x3 matrix with numpy: 0.46 second

Actually, I'm surprised that the python code isn't faster -- I bet psyco 
certainly would be. There is some overhead with numpy arrays, so they 
only help if you are working with large arrays. Try inverting a 
1000X1000 matrix 3 times, and see what you get.

> I will not attempt to generalize, depending on the test operations the
> difference between "pure Python" modules and numpy vary broadly. Sometimes
> "pure Python" wins, sometimes numpy wins.

yup, but I like numpy syntax better anyway.

-Chris



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Christopher Barker, Ph.D.
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