I am trying to draw a map of Guam island in R. Basically, I'd like to draw the coastlines of the island and point some cities on it. I tried maps package but output a line (see the code below). 

library(maps)
data(world.cities)
try<-which((world.cities[,5]>144.6)&(world.cities[,5]<144.94))
world.cities[try,]
map("world", "USA:Guam")


Any feedback is welcome. Thanks. 

Bin


	[[alternative HTML version deleted]]

