Add a progress bar to a function

问题

I've looked at a couple of questions but couldn't find a solution that doesn't use loops. I've looked here and here. Now, how could I add a progress bar that works exactly at the same time as this function:

prog<-function(){
  print("This is a test")
  Sys.sleep(05)
  setTxtProgressBar()
}

The above is a dummy function and I thought of using system.time to capture the time it takes for the print command to execute and use this for the progress bar. How could I make this work, without using a for loop? EDIT I tried this but it is still slow:

prog<-function(y=sort(runif(200)),...){
  pb<-txtProgressBar(...)
  values<-c(0,y,1)
  lapply(values, function(x){
    Sys.sleep(0.5) 
    setTxtProgressBar(pb,x)})
  Sys.sleep(1)
  close(pb)

}

Thanks.

回答1:

There is a package pbapply, which provides a progress bar for apply-functions using:

pblapply(X, FUN, ..., cl = NULL)

It works just like a normal apply-function.

This function: pblapply(1:10, function(x) {Sys.sleep(02); print(x)}) gave this output:

|                                                  | 0 % ~calculating  [1] 1
   |+++++                                             | 10% ~18s          [1] 2
   |++++++++++                                        | 20% ~16s          [1] 3
   |+++++++++++++++                                   | 30% ~14s          [1] 4
   |++++++++++++++++++++                              | 40% ~12s          [1] 5
   |+++++++++++++++++++++++++                         | 50% ~10s          [1] 6
   |++++++++++++++++++++++++++++++                    | 60% ~08s          [1] 7
   |+++++++++++++++++++++++++++++++++++               | 70% ~06s          [1] 8
   |++++++++++++++++++++++++++++++++++++++++         | 80% ~04s          [1] 9
   |+++++++++++++++++++++++++++++++++++++++++++++    | 90% ~02s          [1] 10
   |++++++++++++++++++++++++++++++++++++++++++++++++++| 100% elapsed = 20s

Pretty neat. I don't know if it helps, but worth taking a look.

来源：https://stackoverflow.com/questions/54632346/add-a-progress-bar-to-a-function

标签

function

progress-bar