5.0 | 3 ratings Rate this file 156 downloads (last 30 days) File Size: 9.51 KB File ID: #15410

inpoly mex file

24 Jun 2007 (Updated 05 Oct 2009)

Find points inside or on the border of a polygon

File Information
Description	A fast mex version of the modified inpoly function. please run mexme_inpoly.m to compile mex file on your plateform please run test_inpoly.m for demo
Acknowledgements	The author wishes to acknowledge the following in the creation of this submission: Fast points-in-polygon test This submission has inspired the following: 2D random paths generator integrating leg's contraints
MATLAB release	MATLAB 7.5 (R2007b)
Other requirements	A C compiler
Zip File Content
Other Files	inpoly.c, license.txt, mexme_inpoly.m, test_inpoly.m

Tags for This File
Everyone's Tags	image processing, inpoly, inside, points, polygon, utility
Tags I've Applied
Add New Tags	Please login to tag files.

Comments and Ratings (11)
25 Jun 2007	Darren Engwirda	Well, I guess this is what you get when you "mex" someone else's code... This mex file is based on an old version of my "inpoly.m" function. Unfortunately for the author I've made significant improvements to the algorithm since then and a different algorithm is used in my new "inpoly.m" function. This mex file appears to be slower than my new "inpoly.m" function by a factor of between 3 and 4 on the examples I've tested, even though I have still only coded it as a .m file. There is also no "help inpoly" available unless you directly open the .c file and it also seems that the inputs are required to be transposed when compared with the original "inpoly.m" function. As with all versions/copies of "inpoly" the point of this code is that it's faster than the MATLAB "inpolygon.m" function, especially for large inputs.
26 Jun 2007	Sébastien Paris	Yes in fact, I did this mex file a long times ago. I realized that you update the algorithm. Maybe if I had 1 hour, I'll recreate the new version of this mex-file. If not, I'll remove this submission
26 Jun 2007	Sébastien Paris	sorry for my poor english level skill ...
19 Mar 2009	Martin Podt	Very useful. On the examples I have tested, the current mex version of inpoly is about 2 times faster than the *.m file.
19 Mar 2009	Luigi Giaccari	Very fast!!! well done. I thing I found an error in the demo file: The second demo model is buggy: the polygon is self-interecant!!
22 Mar 2009	USTC ÁÔ	it sounds like inpoltgon.
25 Mar 2009	Korea Univ Saleh	some points are on the edges of the polygon and the function can not detect that. what is the reason?
25 Mar 2009	Sebastien Paris	Please give me an example of this bahaviour.
02 Oct 2009	John Kua	Thanks! This has been very useful on a number of projects! One problem - the function does not handle an empty input array of [2 x 0] and crashes MATLAB. Adding a check of the input dimensionality with a warning if the input is empty and perhaps returning an empty array would be nice.
03 Oct 2009	Sebastien Paris	You are right, I'll upload a version with argument checking. Thanks
07 Oct 2009	Nicolas Billard	Very good function used on my project. Thanks.

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Updates
03 Sep 2007	New algorithm imcorporated. Speed improvement between 50% up to 100%
03 Oct 2009	- Inputs arguments checking - Should compile with Linux/GCC
05 Oct 2009	-Inputs arguments checking -Should compile on Linux

Tag Activity for this File
Tag	Applied By	Date/Time
inpoly	Sebastien Paris	05 Oct 2009 12:27:54
points	Sebastien Paris	05 Oct 2009 12:27:54
inside	Sebastien Paris	05 Oct 2009 12:27:54
polygon	Sebastien Paris	05 Oct 2009 12:27:54
utility	Sebastien Paris	05 Oct 2009 12:27:54
image processing	Sebastien Paris	05 Oct 2009 12:27:54

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