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From: "Bruno Luong" <b.luong@fogale.findmycountry>
Newsgroups: comp.soft-sys.matlab
Subject: Re: The largest Triangle that can fit in convex hull
Date: Fri, 8 May 2009 07:01:02 +0000 (UTC)
Organization: FOGALE nanotech
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"Matt " <xys@whatever.com> wrote in message <gu039t$m0c$1@fred.mathworks.com>...

> 
> So you would approximate the convex hull with a polyhedron and then apply your vertex searching method?

No, *I* don't (OP probably can tell you yes or no). I assumed this is an input. When OP tells "convex hull", I assume he can provide either (A &  b matrices) or alternatively the set of vertexes by other computation mean. These are to me the basic boiled-down representations of convex set in R^2 (on a computer). I'm not awared of other method, and if they are the only one that exist or known, then this should be implicitly understood as the representation of the geometry object.

To take a parallel, when people tells: "I would like to solve a linear equation with Matlab", I would assume they already have some how a matrix and right hand side in matlab arrays. 

> Is it clear how many vertices and where the vertices need to be placed to get a sufficiently good approximation? 

It's probably a valid  and very important question question. But this question falls outside the scope. To take a parallel with the above example, we usually do not need to ask people: "how do you build your matrix?" in order to advise them "use backslash". This should be classified as discretization method (think the parallel with solving a PDE, which has infinity of number of dimensions), it's entirely an art by itself, and there is probably no best universal answer.

Bruno