Re: determining boundary of a region in n-dimensional euclidean space

• To: mathgroup at smc.vnet.net
• Subject: [mg117202] Re: determining boundary of a region in n-dimensional euclidean space
• From: Nabeel Butt <nabeel.butt at gmail.com>
• Date: Fri, 11 Mar 2011 04:34:23 -0500 (EST)

```Dear Carter
Thanks.This is very helpful  and ill check it out !
Nabeel

On Thu, Mar 10, 2011 at 4:52 PM, W Craig Carter <ccarter at mit.edu> wrote:

> Hello Nabeel.
> I believe I remember seeing something in this group about an implementation
> of ConvexHull3D, but I can't find it in the ComputationalGeometry Context.
>
> It was not terribly difficult to run qhull (www.qhull.org/, a swiss-army
> knife for convex hulls and tesselations in higher dimensions) outside of
> mathematica and then import the result back into mathematica.  I did this
> once for a convex hull in 3D, but lost it in a disk crash. If anyone
> recreates it, I wouldn't mind getting a copy.
> Craig
>
>
>
> On Mar 10, 2011, at Thu, Mar 10, 11 ---4:03 PM, Nabeel Butt wrote:
>
> > Hi Daniel
> >      Thanks for your response.Actually the problem is two-fold here.The
> > first step is to actually extract the boundary points from a set of
> points
> > in a list.I have found that built-in ConvexHull function in mathematica
> can
> > do for 2-dimensions this extraction process.There exists a program also
> for
> > 3-dimensions written in mathworld.To my best of my knowledge it hasnt
> been
> > implemented in higher dimensions that well in mathematica(was just a
> random
> > google search though !!) . Anyways after we get the list for boundary
> > points , like you said I can use Interpolation on list to represent it
> > numerically.What I am more interested in is actually extracting the
> boundary
> > points from a set of points -Does there exist more robust convexhull like
> > functions for higher dimensions ? Or after having a list of points I can
> > send them to another software which helps me get the convex hull in high
> > dimensions.Possibly if I can call another software inside mathematica
> that
> > would be great.
> >       Thanks once again.
> >                                  Nabeel
>
>

--
"We have not succeeded in answering all our problems.The answers we have
found only serve to raise a whole set of new questions.In some ways we feel
that we are as confused as ever,but we believe we are confused on a higher
level and about more important things."
"Maybe one day we get to see all the beauty present in this world"

Nabeel Butt
UWO,London