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FIGURE 2. Distances between three selected locations from the fdata sample data. Distances given between points are in km.
>data(fdata.lats) >fd.subset<-coordinates(fdata.lats)[1:3,] >earth.dist(fdata.lats[1:3,])
locA locB locB 893.4992 locC 776.3101 867.2648
>map("state") >polygon(fd.subset) >text(c(-110,-101,-106),c(42,42,47),labels=round(earth.dist(fd.subset)[c(1, +3,2)])) >points(fd.subset,pch=16,col="white",cex=3) >points(fd.subset,pch=1,cex=3) >text(fd.subset,label=LETTERS[1:3])
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