[R-sig-Geo] Adjacency matrix of higher order (from winbugs to R)

[Roger Bivand]

On Thu, 4 Mar 2010, Julien Beguin wrote:

> Hi everyone,
> 
> I am trying to find a way to calculate an adjacency matrix from a polygon
> shapefile to make a CAR model in winbugs, but I would like to vary the order
> of neihborhood. I checked previous messages on the list but did not find
> this specific topic. I used the the spdep package to create an adjacency
> matrix (in list format) of order 2 and it works pretty fine:

Did you look at ?nblag - is that what you need?

Roger

> ---------------------------------------------------------------------------
> ------------
>    shape <- readShapePoly("path_to_my_shapefile", IDvar="Id")
>    shape_nb<-poly2nb(shape)
> 
>    data<-list(
>    N = length(shape_nb),
>    num=sapply(shape_nb, length),
>    adj=unlist(shape_nb),
>    lst = attr(shape_nb, "region.id"),
>    adj2 = lst[unlist(shape_nb)],
>    sumNumNeigh=length(unlist(shape_nb)
>    )
> ---------------------------------------------------------------------------
> -------------
> is everyone know how to calculate an adjacency matrix in R for polygon
> shapefile but for higher orders of neihborhood (ex: 3,4,5, etc...)? I did
> not see any option with the function poly2nb() in spdep package but I
> imagine that other tools have to exist. Your help would be greatly
> appreciated.
> 
> Best regards,
> 
> Julien
> 
>

-- 
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