R: Center output text in R console (R studio and R.app)

Question

I am executing some R scripts with a source() command and then flushing the console. The only thing that I want visible in the console is some text with a progress report of the script, after that some progress bars are displayed, all the rest of the code is hidden. I am printing my progress report to the console by manually adding the text using the cat() function as below.

cat("\014")
cat("  =====================================\n")
cat("  ========== PROGRESS REPORT ==========\n")
cat("  =====================================\n")
cat("\n")

# progress bar implementation

What I was wondering: Is there a way to center the text automatically in the middle of the console so that it adjusts dynamically when you resize the window size of the console? I am looking for a way that works both in R Studio and also baseR in Windows and Mac OS X.

Answer 1

You could try something like this. This may or may not be exactly centered, it depends on the current console width (which is floored if an odd number occurs in the calculation of p).

centerText <- function() {
    width <- getOption("width")
    out <- "=======================================\n"
    mid <- "=========== PROGRESS REPORT ===========\n"
    ws <- rep(" ", floor((width - nchar(out))/2))
    cat(ws, out, ws, mid, ws, out, sep = "")
}

centerText()

It works in RStudio, but I'm not sure if it works in the normal R console. Might need some tweaking.