[R] Concave Hull

[Charles Geyer]

> Message: 64
> Date: Mon, 19 Jan 2009 15:14:34 -0700
> From: Greg Snow <Greg.Snow at imail.org>
> Subject: Re: [R] Concave Hull
> To: Michael Kubovy <kubovy at virginia.edu>, r-help
> 	<r-help at r-project.org>
> Message-ID:
> 	<B37C0A15B8FB3C468B5BC7EBC7DA14CC61C8360835 at LP-EXMBVS10.CO.IHC.COM>
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> 
> I don't know if it is the same algorithm or not, but there is the function "chull" that finds the convex hull.

Also the R function "redundant" in the contributed package "rcdd" efficiently
finds convex hulls in d-dimensional space for arbitrary d (chull only does
d = 2).  See Sections 4.2 and 5.2 of the rcdd package vignette.

> Hope this helps,
> 
> -- 
> Gregory (Greg) L. Snow Ph.D.
> Statistical Data Center
> Intermountain Healthcare
> greg.snow at imail.org
> 801.408.8111
> 
> 
> > -----Original Message-----
> > From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-
> > project.org] On Behalf Of Michael Kubovy
> > Sent: Saturday, January 17, 2009 9:49 AM
> > To: r-help
> > Subject: [R] Concave Hull
> > 
> > Dear Friends,
> > 
> > Here is an algorithm for finding concave hulls:
> > http://get.dsi.uminho.pt/local/
> > 
> > Has anyone implemented such an algorithm in R?
> > 
> > RSiteSearch('concave hull') didn't reveal one (I think).
> > 
> > _____________________________
> > Professor Michael Kubovy
> > University of Virginia
> > Department of Psychology
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> > Skype name: polyurinsane
> > 
> > 
> > 
> > 
> > 
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