Rank: 71 based on 2703 downloads (last 30 days) and 11 files submitted

Luigi Giaccari

E-mail: giaccariluigi@msn.com
Company/University: Università Degli Studi Dell'Aquila (Italy)
Lat/Long: 42.019833, 14.5429

Personal Profile:: 5th year student of mechanical engineer at l'Aquila university
Professional Interests:: Algorithms for fun

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Files Posted by Luigi				View all 1 - 5 of 11
Updated	File	Tags	Downloads (last 30 days)	Comments	Rating
08 Jan 2009	QuickerHull Algorithm A trick to improve performances of convhulln on large models in low dimension. Author: Luigi Giaccari	2d, 3d, aerospace, automotive	13	0
07 Jan 2009	Surface recostruction from scattered points cloud Part2 Builds a triangulated surface given a 3D points cloud. They do not need to be in the z=f(x,y) form. Author: Luigi Giaccari	3d, cloud, cocone, crust	87	0
02 Jan 2009	Surface recostruction from scattered points cloud Part1 Builds a triangulated surface given a 3D points cloud. They do not need to be in the z=f(x,y) form Author: Luigi Giaccari	3d, surface, recostructi..., mesh	550	1	5.0 5.0 \| 2 ratings
02 Jan 2009	Ultra-fast Nearest neighbor search Builds a nearest neighbor graph in a very short time.In many cases is faster than ANN library. Author: Luigi Giaccari	kd tree, search, optimizatio..., image compr...	543	7	5.0 5.0 \| 3 ratings
11 Dec 2008	K-nearest neighbors search A Mex implementation of the brute search algorithm. Supports KNN and Radius Search. Author: Luigi Giaccari	image proce..., mathematics, optimizatio..., statistics	126	0

Comments and Ratings by Luigi		View all 1 - 5 of 16
Updated	File	Comments	Rating
05 Jan 2009	Cam Simulator Given a set of motion programs this interface plots the cam profile and rotates it. Author: Husam Aldahiyat	Wonderful Congratulations, It is a very usefull routine, with nice graphical plots. I need to ask you a few question: How to obtain profile coordinates? Does it computes the profile for roller follower? At the end a few possible improvement: -rocker roller follower instead of translating. -You can also includes the detachement problem which is very useffull for high frequency cams. -Please insert a better documentation on how to use use this beatiful utilitie. I took 20 minutes to understand how to start!!!! Thank you again
04 Jan 2009	Conjugate Gradient Method Conjugate Gradient Method to solve a system of linear equations Author: Yi Cao	A\b uses cholesky factorization if A is simmetric. It swithes to gauss method when A is not simmetric and the factorization fails due to negative sqrt input. I don't know if it is present in all version, but there already is a conjgrad method in matlab. Try: help pcg Anyway thank to Cao, submissions that works are always usefull, in the worst case you can study the algorithm.
23 Dec 2008	Fast Convex Hull Algorithm m-code routine to compute convex hull in 2D space. Usually faster than the Matlab convhull Author: Luigi Giaccari	From your timing I suspect you did the same error of Tomas Clark You should turn the profile off, profile only works on m-code, the native convhull is a mex routine, so it only slow down my algorithm. To be sure please send a report about the way rou ran your test. If there is any problem I'll try to fix it.
20 Dec 2008	Efficient K-Nearest Neighbor Search using JIT A small but efficient tool to perform KNN search Author: Yi Cao	I think someone, maybe not the author, is faking the download number. My opinion is that this is a very usefull routine, very well commented and totally m-coded. The performances of course can not be the ones declared in the presentation. The algorithm it is just a brute search can only be competitive against kd-tree data structure for a small number of search and reference points. For KNN search is used the sort function to find K-neighbours, and this is a very brute algorithm. I Know this the fastest m-code way to find KNN, but it is clear that kd-trees will overcome this algorithm for very small models.
20 Dec 2008	A christmas tree plot A Small piece of code that constructs a coloured christmas tree with some presents and snow. Author: Anselm	Very nice

Comments and Ratings on Luigi's Files			View all 1 - 5 of 27
Updated	File	Comment by	Comments	Rating
06 Jan 2009	Ultra-fast Nearest neighbor search Builds a nearest neighbor graph in a very short time.In many cases is faster than ANN library. Author: Luigi Giaccari	Tursa, James	To Matt Dash: lcc is a C compiler, not a C++ compiler, so you should not expect lcc to compile cpp files.
23 Dec 2008	Fast Convex Hull Algorithm m-code routine to compute convex hull in 2D space. Usually faster than the Matlab convhull Author: Luigi Giaccari	Giaccari, Luigi	From your timing I suspect you did the same error of Tomas Clark You should turn the profile off, profile only works on m-code, the native convhull is a mex routine, so it only slow down my algorithm. To be sure please send a report about the way rou ran your test. If there is any problem I'll try to fix it.
21 Dec 2008	Fast Convex Hull Algorithm m-code routine to compute convex hull in 2D space. Usually faster than the Matlab convhull Author: Luigi Giaccari	O'Connor, Derek	Using an 8-core 2x Intel(R) Xeon(R) CPU E5345 @ 2.33GHz with Matlab R2008a on Windows Vista 64, Thomas Clark's test gave these results : Matlab ConvHull2D 0.0016 0.0003 0.0007 0.0007 0.0008 0.0009 0.0008 0.0011 0.0009 0.0025 0.0011 0.0040 0.0014 0.0089 0.0029 0.0155 0.0048 0.0325 0.0109 0.0644 0.0274 0.1530 0.0648 0.3265 0.1875 0.7368 0.5172 1.5775 1.1987 3.6044 ConvHull2D seems to be 3 times slower than Matlab's convhull. Derek O'Connor
20 Dec 2008	In Polygon test for convex polygon Detects points inside a convex polygon in 2D space. Should be faster than general inpolygon. Author: Luigi Giaccari	Maula, Maula	Nice one, I'm looking for possibilities x and y are not the same size, i've been googling for an example for such operation, but no luck.
07 Dec 2008	Ultra-fast Nearest neighbor search Builds a nearest neighbor graph in a very short time.In many cases is faster than ANN library. Author: Luigi Giaccari	Jordan, Michael	Excellent code. I am looking forward to your extension to 3D, k-neighbour and range search, which are more useful functions than the current one.

Top Tags Applied by Luigi	1 - 5 of 83
mathematics, points, delaunay, mesh, aerospace

Files Tagged by Luigi				View all 1 - 5 of 11
Updated	File	Tags	Downloads (last 30 days)	Comments	Rating
08 Jan 2009	QuickerHull Algorithm A trick to improve performances of convhulln on large models in low dimension. Author: Luigi Giaccari	2d, 3d, aerospace, automotive	13	0
07 Jan 2009	Surface recostruction from scattered points cloud Part2 Builds a triangulated surface given a 3D points cloud. They do not need to be in the z=f(x,y) form. Author: Luigi Giaccari	3d, cloud, cocone, crust	87	0
02 Jan 2009	Surface recostruction from scattered points cloud Part1 Builds a triangulated surface given a 3D points cloud. They do not need to be in the z=f(x,y) form Author: Luigi Giaccari	3d, surface, recostructi..., mesh	550	1	5.0 5.0 \| 2 ratings
02 Jan 2009	Ultra-fast Nearest neighbor search Builds a nearest neighbor graph in a very short time.In many cases is faster than ANN library. Author: Luigi Giaccari	kd tree, search, optimizatio..., image compr...	543	7	5.0 5.0 \| 3 ratings
11 Dec 2008	K-nearest neighbors search A Mex implementation of the brute search algorithm. Supports KNN and Radius Search. Author: Luigi Giaccari	image proce..., mathematics, optimizatio..., statistics	126	0

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