x_y <-  read.table("Relative_elevation_all.txt", header=T)
x_y$site[x_y$site==102] <-1
x_y <- subset(x_y,site!= 101)
x_y <- subset(x_y,site!= 0)
xc <- tapply(x_y$X_COORD,x_y$site,mean)
yc <- tapply(x_y$Y_COORD,x_y$site,mean)
sites <- unique(x_y$site)
o <- order(sites)
sites <- sites[o]
plot((xc-min(xc))/1000,(yc-min(yc))/1000,xlim=c(-0.1,1),pch=16)
coord <- cbind(sites, (xc-min(xc))/1000,(yc-min(yc))/1000)
coord
write.table(coord,file="Bald_coordinates.txt", sep = " ",
            col.names = TRUE)