[R-sig-Geo] R-sig-Geo Digest, Vol 43, Issue 14

[Nicholas Lewin-Koh]

Hi Tim,
I am not quite sure what you are getting at here. Do you want to
intersect
polygons and then select the set of lines that form the outer perimeter?
Do you wan the convex hull of a set of polygons. I guess I have been out
of the
GIS world to long. It seems to me that this would be something easy to
solve,
just tedious iteration of the polygon coordinates and some
triangulation.

Nicholas

> Date: Thu, 15 Mar 2007 10:49:23 -0500
> From: "Tim Keitt" <tkeitt at gmail.com>
> Subject: [R-sig-Geo] polygons to arcs?
> To: r-sig-geo at stat.math.ethz.ch
> Message-ID:
> 	<6262c54c0703150849qe60ab14nfef1eb3bf73dfb5d at mail.gmail.com>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
> 
> Is there an 'sp' function that takes a polygon as its argument and
> returns a set of line objects corresponding to the arcs in the
> polygon?
> 
> Or better yet, a function that given a set of polygons, returns the
> hull? (ie the set of singleton arcs after applying the polys to arcs
> function)
> 
> THK
> 
> -- 
> Timothy H. Keitt, University of Texas at Austin
> Contact info and schedule at http://www.keittlab.org/tkeitt/
> Reprints at http://www.keittlab.org/tkeitt/papers/
> ODF attachment? See http://www.openoffice.org/
> 
> 
>