showing a status message in R

Question

I\'d like to write a function that presents to the user a status message that shows something like the time, the percent complete, and the current status of a process. I can

Answer 1

The utils package contains the txtProgressBar and functions for updating it which can be used to show the percent complete of a process.

See the up1, up2 and up3 functions that are created during a call to txtProgressBar for examples of how updates are handled without scrolling the console.

Answer 2

There may be more elegant ways to do this, but this could do it:

test.message <- function() {
  for (i in 1:9){
    cat(i)
    Sys.sleep(1)
    cat("\b")
  }

}

If you're automatically generating your message, you'll need to calculate how many \b characters to output to back up the correct amount, but that's pretty straightforward.

Answer 3

How about something like this?

for(i in 1:10) {
  Sys.sleep(0.2)
  # Dirk says using cat() like this is naughty ;-)
  #cat(i,"\r")
  # So you can use message() like this, thanks to Sharpie's
  # comment to use appendLF=FALSE.
  message(i,"\r",appendLF=FALSE)
  flush.console()
}

Answer 4

Here's some bling bling. From ?tcltk::tkProgressBar.

pb <- tkProgressBar("test progress bar", "Some information in %",
        0, 100, 50)
Sys.sleep(0.5)
u <- c(0, sort(runif(20, 0 ,100)), 100)
for(i in u) {
    Sys.sleep(0.1)
    info <- sprintf("%d%% done", round(i))
    setTkProgressBar(pb, i, sprintf("test (%s)", info), info)
}
Sys.sleep(5)
close(pb)