aligned<-function(x,y,e) { if(var(x)==0 | var(y)==0) TRUE else abs(cor(x,y))>e } e<-0.999 db<-read.csv(file="C:\\coordinates.csv",sep=";",header=T) attach(db) points<-c(16,85,89,94) plot(x,y,col="white") for(i in points) { points(x[i],y[i],col="dark red",pch=19) text(x[i],y[i],name[i],cex=0.5,pos=1) text(x[i],y[i],i,cex=0.5,pos=3) } px<-x[points] py<-y[points] aligned(px,py,e) rl <- lm(py~px) abline(rl)