read.gwt2nb {spdep}R Documentation

Read and write GeoDa GWT spatial neighbour files

Description

Usage

read.gwt2nb(file, region.id=NULL)
write.sn2gwt(sn, file, shpfile=NULL, ind=NULL)

Arguments

file name of file with GWT lattice data
region.id region IDs
sn a spatial.neighbour object
shpfile Shapefile name taken from GWT file for this dataset
ind region id indicator variable name

Details

Now attempts to honour the region.id argument given when reading GWT files.

Value

read.gwt2nb returns a neighbour "nb" object with the generalised weights stored as a list element called "dlist" of the "GeoDa" attribute.

Author(s)

Roger Bivand Roger.Bivand@nhh.no

References

Luc Anselin (2003) GeoDa 0.9 User's Guide, pp. 80–81, Spatial Analysis Laboratory, Department of Agricultural and Consumer Economics, University of Illinois, Urbana-Champaign, http://agec221.agecon.uiuc.edu/csiss/pdf/geoda093.pdf

See Also

read.gal

Examples

data(baltimore)
STATION <- baltimore$STATION
gwt1 <- read.gwt2nb(system.file("etc/weights/baltk4.GWT", package="spdep")[1],
 STATION)
cat(paste("Neighbours list symmetry;", is.symmetric.nb(gwt1, FALSE, TRUE),
 "\n"))
listw1 <- nb2listw(gwt1, style="B", glist=attr(gwt1, "GeoDa")$dist)
tmpGWT <- tempfile()
write.sn2gwt(listw2sn(listw1), tmpGWT)
gwt2 <- read.gwt2nb(tmpGWT, STATION)
cat(paste("Neighbours list symmetry;", is.symmetric.nb(gwt2, FALSE, TRUE),
 "\n"))
diffnb(gwt1, gwt2)

[Package Contents]