[R-sig-Geo] distmap

[Roger Bivand]

On Fri, 22 Jun 2007, Agustin Lobo wrote:

> Dear sig-geos,
>
> I have to calculate a distmap (that is, a map
> in which the value of each cell is the distance
> from the cell to a given object) for a set of polygons.
> It seems to me that distmap.owin in spatstat would do it
> fine, but distmap.owin does not accept objects
> imported from shp vectors via readOGR. distmap.owin requires
> type "polygonal" and readOGR yields class 'SpatialPolygonsDataFrame'
> Is there any way to cast or convert from 'SpatialPolygonsDataFrame'
> to "polygonal" or an alternative function to calculate the distances
> to the boundaries of the polygons?

Have you tried coercing with as(x, "owin") in maptools?

Roger

>
> Thanks
>
> Agus
>
>

-- 
Roger Bivand
Economic Geography Section, Department of Economics, Norwegian School of
Economics and Business Administration, Helleveien 30, N-5045 Bergen,
Norway. voice: +47 55 95 93 55; fax +47 55 95 95 43
e-mail: Roger.Bivand at nhh.no