[prev in list] [next in list] [prev in thread] [next in thread] 

List:       r-sig-geo
Subject:    Re: [R-sig-Geo] Singlepart to multipart
From:       Roger Bivand <Roger.Bivand () nhh ! no>
Date:       2013-10-29 19:32:22
Message-ID: alpine.LRH.2.03.1310292030311.3464 () reclus ! nhh ! no
[Download RAW message or body]

On Tue, 29 Oct 2013, Jonathan Greenberg wrote:

> R-sig-geo'ers:
>
> If I have a SpatialPolygonsDataFrame with a field "MYID", how do I go about
> coercing that object to a multipart polygon, where I am "merging" on the
> MYID field?

maptools::unionSpatialPolygons() which calls rgeos::gUnaryUnion, so go to 
rgeos::gUnaryUnion first unless you have challenged geometries - if hole 
problems use maptools::checkPolygonsHoles first.

Hope this helps,

Roger

>
> --j
>
>

-- 
Roger Bivand
Department of Economics, NHH Norwegian School of Economics,
Helleveien 30, N-5045 Bergen, Norway.
voice: +47 55 95 93 55; fax +47 55 95 95 43
e-mail: Roger.Bivand@nhh.no

_______________________________________________
R-sig-Geo mailing list
R-sig-Geo@r-project.org
https://stat.ethz.ch/mailman/listinfo/r-sig-geo
[prev in list] [next in list] [prev in thread] [next in thread]