Dear list,

I have a question regarding the included polygon in the khat function of the splancs library defining the area where points appear.

I have not only one simple polygon included, my map includes several islands. 

I read my map which was a shape file by readShapeSpatial of the maptools library.

Then I split up the SpatialPolygonsDataFrame into the included polygons by

coor <- NULL
for (i in 1:[number of polygons]) coor<- rbind(coor,map@polygons[[1]]@Polygons[[i]]@coords)

I am using now this newly generated polygon "coor" in the khat command.

k_funk_ca <- khat(as.points(cases), coor,s=0:1000)

I do not know if there is a problem using multiple polygons that way or if khat produces then only results for the "first" polygon or even completely wrong results. 

Does anyone know the answer?

Thanks a lot,

Sven Schmiedel



PhD student at Copenhagen Unversity
Danish Cancer Society
Institute for Cancer Epidemiology

	[[alternative HTML version deleted]]

