Rank: 1467 based on 51 downloads (last 30 days) and 5 files submitted
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Peter Li

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The Salk Institute

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Files Posted by Peter View all
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08 Nov 2011 More intuitive subplot Matlab's subplot is useful for throwing figures together but the indexing is very counter-intuitive. Author: Peter Li plot, gui 5 2
29 Sep 2011 Faster/parallel random number generator via standard C++ Mersenne Twister from Boost Random: same as modern Matlab, faster. Plus flexible distributions! Author: Peter Li random number, monte carlo, mersenne twister, boost, c, actors 6 3
25 Aug 2011 nth_element MEX wrap of C++ nth_element. Plus fast_median, a faster median function. Also can operate in-place. Author: Peter Li nth_element, c, mex, median, selection, selection algorithm 9 14
  • 4.0
4.0 | 1 rating
18 Apr 2007 LSM File Toolbox Functions for reading info databases of Zeiss LSM confocal microscope files. Author: Peter Li data import, data export, lsm, zeiss, confocal, laser scanning 27 10
  • 4.5
4.5 | 7 ratings
20 Nov 2006 scanfc scanf rewritten to give cell arrray output Author: Peter Li data import, data export, scanf, mex, input, io 4 0
Comments and Ratings by Peter View all
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07 Dec 2011 nth_element MEX wrap of C++ nth_element. Plus fast_median, a faster median function. Also can operate in-place. Author: Peter Li

Hi jianbo, I think this is the same as Martijn's request? I may have time to give this a try in the next month or two. Unfortunately I expect it to be significantly slower than just returning the partially-sorted output. This is a limitation of the way the C++ standard library is written and I'm not sure I can get around it. Bruno's version may have more flexibility to be efficient here.
11 Nov 2011 More intuitive subplot Matlab's subplot is useful for throwing figures together but the indexing is very counter-intuitive. Author: Peter Li

Okay, should be working now; simple but helpful.
08 Nov 2011 More intuitive subplot Matlab's subplot is useful for throwing figures together but the indexing is very counter-intuitive. Author: Peter Li

Sorry guys, the current version is buggy; uploaded the wrong version. I'm fixing it now, will post when the fixed one is up.
03 Oct 2011 Faster/parallel random number generator via standard C++ Mersenne Twister from Boost Random: same as modern Matlab, faster. Plus flexible distributions! Author: Peter Li

It appears that the minimum spacing for Boost Random 1.47 uniform_01 distribution (doubles between 0 and 1) is ~2.3e-10, which indicates that the RNG is simply taking each int generated by the Twister and (effectively) dividing it by the maximum int.

Matlab's RNG appears to use two int from the Twister for each [0,1] double, using the first int for the more significant bits and the second for the less significant bits.

So essentially using this library will give you faster RNG over Matlab at the expense of lower resolution.
03 Oct 2011 Faster/parallel random number generator via standard C++ Mersenne Twister from Boost Random: same as modern Matlab, faster. Plus flexible distributions! Author: Peter Li

I've noticed that the minimum spacing of random numbers generated by Boost Random 1.47 is greater than the minimum produced by Matlab; it appears to me that Matlab is using twice as many underlying integer seeds from the Twister to produce each double compared to Boost's behavior. So if you need very fine-grained doubles, this may be an issue for you.
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27 Feb 2012 nth_element MEX wrap of C++ nth_element. Plus fast_median, a faster median function. Also can operate in-place. Author: Peter Li Klemm, Matthias

As a follow up on WurmD's comment: "all" Matlab functions work on the first dimension by default so I think a "replacement" method should do so too.
The current behavior of fast_median breaks things like:
med = median(data(:));

Currently I can't use fast_median in my code as I need to be able to change the filtering function and I don't want to code in some special treatment for fast_median... :/

Would that be possible?
07 Dec 2011 nth_element MEX wrap of C++ nth_element. Plus fast_median, a faster median function. Also can operate in-place. Author: Peter Li Li, Peter

Hi jianbo, I think this is the same as Martijn's request? I may have time to give this a try in the next month or two. Unfortunately I expect it to be significantly slower than just returning the partially-sorted output. This is a limitation of the way the C++ standard library is written and I'm not sure I can get around it. Bruno's version may have more flexibility to be efficient here.
05 Dec 2011 nth_element MEX wrap of C++ nth_element. Plus fast_median, a faster median function. Also can operate in-place. Author: Peter Li jianbo

Hi, I am interested to have index, rather of the n-th element output, thx.
22 Nov 2011 LSM File Toolbox Functions for reading info databases of Zeiss LSM confocal microscope files. Author: Peter Li Kristin

lsminfo worked out of the box for me. thanks!
11 Nov 2011 More intuitive subplot Matlab's subplot is useful for throwing figures together but the indexing is very counter-intuitive. Author: Peter Li Li, Peter

Okay, should be working now; simple but helpful.
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c, data export, data import, io, mex
Files Tagged by Peter View all
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Updated   File Tags Downloads
(last 30 days) 		Comments Rating
08 Nov 2011 More intuitive subplot Matlab's subplot is useful for throwing figures together but the indexing is very counter-intuitive. Author: Peter Li plot, gui 5 2
29 Sep 2011 Faster/parallel random number generator via standard C++ Mersenne Twister from Boost Random: same as modern Matlab, faster. Plus flexible distributions! Author: Peter Li random number, monte carlo, mersenne twister, boost, c, actors 6 3
25 Aug 2011 nth_element MEX wrap of C++ nth_element. Plus fast_median, a faster median function. Also can operate in-place. Author: Peter Li nth_element, c, mex, median, selection, selection algorithm 9 14
  • 4.0
4.0 | 1 rating
22 Jun 2007 Add folders to path excluding .svn Changes to genpath to exclude the .svn to the path Author: H. Brian Hui addpath, genpath, svn 5 0
18 Apr 2007 LSM File Toolbox Functions for reading info databases of Zeiss LSM confocal microscope files. Author: Peter Li data import, data export, lsm, zeiss, confocal, laser scanning 27 10
  • 4.5
4.5 | 7 ratings

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