library(maps)
ncmap <- map("county", "north carolina", fill=TRUE, col="transparent", plot=FALSE)
data(ncmap)
IDs <- sapply(strsplit(ncmap$names, ","), function(x) x[2])
nc2 <- as.SpatialRings.map(ncmap, IDs)
plotSpatialRings(nc2)
invisible(text(getSRSringsLabptSlots(nc2), labels=getSRSringsIDSlots(nc2), cex=0.6))
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