[R-sig-Geo] nb file using spdep tools only

[Philip A. Viton]

(Very new-user problem, sorry) Can anyone help me with generating an 
nb file using only R/spdep tools, ie without using GeoDa as an 
intermediate step? I have a shape file, say "myshape.shp" with its 
associated (eg) dbf files. My idea is to read it with maptools, then 
convert to polygons, neighbors, then finally weights.

In R (2.5.1 under Winxp):

library(spdep)

map <-readshape("myshape")
# seems OK

mappoly <-Map2poly(map,region.id="OBJECTID")
# also seems OK, though it takes a LONG time

mapnb = poly2nb(mappoly,row.names = NULL, 
snap=sqrt(.Machine$double.eps), queen=TRUE)

# problem is, this hangs R (GUI says "Not responding")

(then, if I ever get this far, use nb2listw to generate the weights). 
The shape file is a US-48-states file, so not, I would assume, too 
big; but obviously something is going wrong. Can anyone suggest a better way?


Thanks!

------------------------
Philip A. Viton
City Planning, Ohio State University
275 West Woodruff Avenue, Columbus OH 43210
viton.1 at osu.edu