[R-sig-Geo] rbind of SpPolDFs

[Roger Bivand]

On Tue, 18 May 2010, Agustin Lobo wrote:

>
> Thanks. I have to do it this way as the tables are inconsistent:
>
> BesosBoundary at data <- data.frame(Basin="Besos")
> TerBoundary at data <- data.frame(Basin="Ter")
> BesosBoundary <- spChFIDs(BesosBoundary, "Besos")
> TerBoundary <- spChFIDs(TerBoundary, "Ter")
> delme <- rbind.SpatialPolygonsDataFrame(BesosBoundary,TerBoundary)
>
> Nevertheless, as I have several of these shape files, I'm trying a loop.
> But while the following works:
>> i <- 1
>> basnom <- unlist(strsplit(bas[i], "Boundary"))
>> basnom
> [1] "Besos"
>
>> slot(BesosBoundary,"data") <- data.frame(Basin = basnom)
>
> the following (which I need for using the names in an array) does not:
>> bas[i]
> [1] "BesosBoundary"
>
>> slot(get(bas[i]),"data") <- data.frame(Basin = basnom)
> Error in slot(get(bas[i]), "data") <- data.frame(Basin = basnom) :
>  could not find function "get<-"
>
> am I doing something wrong or have I hitted an inconsistency?

The error message seems explicit. Use get() first to a temporary local 
object, do slot()<- on that object, and assign() back to bas[i]. Untried.

Roger

>
> 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