How to output the label of points in scatterplot to bash console

Question

I have a simple R-Script:

args <- commandArgs(TRUE)

inp <- read.csv(args[1],sep="\t",header=FALSE,stringsAsFactors=FALSE)

firstCol <- inp$V2
secondCol <- inp$V3

pdf(args[2])
plot(firstCol,secondCol,xlab="#",ylab="maxLength")
dev.off()

I run it from a bash script to generate a basic plot.

Now I want to use X11() to plot directly into a window and not into a PDF.

What I want now is to appear the label (in inp$V1 ) of every dot on the console when hovering over a point or klicking onto it.

How to do?

Answer 1

The identify function lets you click on points and it returns the index value for the points clicked on that could be used to subset a vector of labels.

For identification when hovering (instead of clicking) you can look at the HTKidentify function in the TeachingDemos package.

Edit

Here is an example using identify that may be more what you want (I tested it on windows, not unix/X11):

x <- runif(26)
y <- rnorm(26)
plot(x,y)
while(length(tmp <- identify(x,y, plot=FALSE, n=1))) {
  cat(letters[tmp],'\n')
}

The plot=FALSE tells identify to not put the label on the plot and the n=1 tells it to return after you click on 1 point (the while goes back to identifying more points, but prints out the label immediately).

Obviously you would create other labels to use than just the letters.