[R-sig-Geo] edit.nb problem with an island

[Marc Marí Dell'Olmo]

Dear all,

I have a cartography with an island, i.e. a polygon that doesn't share
border with other polygons (CODIGO=3120104012). I would like to
manually assign two areas (CODIGO=3120103024 and CODIGO=3120103014) as
a neighborhood areas of this island with the edit.nb function, and
after that to obtain the neighborhood matrix. I have followed this
syntax and I don't understand why the summary(x.nb2) still shows one
region with no link...

If it helps, you can download the map at:
http://dl.dropbox.com/u/14934021/map.zip


Thank you very much,

Marc

map<-readShapePoly("F:/map/map.shp")
map<-map[order(map$CODIGO),]


x.nb<-poly2nb(map)
summary(x.nb)

#Neighbour list object:
#Number of regions: 122
#Number of nonzero links: 724
#Percentage nonzero weights: 4.864284
#Average number of links: 5.934426
#1 region with no links:
#66
#Link number distribution:

 #0  2  3  4  5  6  7  8  9 10 11 12 14
 #1  1  7 19 22 31 21 12  2  2  2  1  1
#1 least connected region:
#101 with 2 links
#1 most connected region:
#29 with 14 links

nb <- x.nb
which(card(nb) == 0)
attr(nb, "region.id")[which(card(nb) == 0)]


x.nb2 <- edit.nb(x.nb,polys=map)

#> x.nb2 <- edit.nb(x.nb,polys=map)
#Identifying contiguity for deletion ...
#No contiguity between chosen points
#Add contiguity? (y/n) y
#added contiguity between point 53 and 67
#Options: quit[q] refresh[r] continue[c] c
#Identifying contiguity for deletion ...
#No contiguity between chosen points
#Add contiguity? (y/n) y
#added contiguity between point 43 and 67
#Options: quit[q] refresh[r] continue[c] q


summary(x.nb2)

#Neighbour list object:
#Number of regions: 122
#Number of nonzero links: 726
#Percentage nonzero weights: 4.877721
#Average number of links: 5.95082
#1 region with no links:
#66
#Non-symmetric neighbours list
#Link number distribution:

 #0  2  3  4  5  6  7  8  9 10 11 12 14
 #1  1  7 18 22 32 21 12  2  2  2  1  1
#1 least connected region:
#101 with 2 links
#1 most connected region:
#29 with 14 links