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Topic: matlab version and "for" loops
Replies: 15   Last Post: Feb 13, 2013 4:53 PM

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Posts: 147
Registered: 3/7/08
Re: matlab version and "for" loops
Posted: Jan 21, 2013 6:16 PM
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"Jan Simon" wrote in message <kdj1jg$i5i$>...
> Dear Jessica,
> Yes, "newer" versions of Matlab interpret loops much faster using the JIT acceleration. Please note that this means "newer" than version 6.1 from June 2001.
> To check the difference type:
> feature('accel', 'off')
> feature('jit', 'off')
> and run your program again.
> If you want to accelerate your code, post it here to get our ideas.
> Kind regards, Jan

Thanks for this information. My problem is in running this code:

%Delete saccades except when they mark the start/stop of image
for i=0:DataLength-1
if strcmp(GazeType(DataLength-i,1),'Saccade')==1|strcmp(GazeType(DataLength- i,1),'Unclassified')==1;
if strcmp(PictureStartColumn2(DataLength-i),'ImageStart')==0
if strcmp(PictureStartColumn2(DataLength-i),'ImageEnd')==0;

The loop often needs to run over 300,000 times (i.e., DataLength=300,000). After nearly 8 hours , I stopped the code to find that it was only up to 53,988.

I am basically trying to delete rows in a dataset that are marked as "Saccade" or "Unclassified" unless they are marked as "ImageStart" or "ImageEnd"

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