How to make execution pause, sleep, wait for X seconds in R?

Question

How do you pause an R script for a specified number of seconds or miliseconds? In many languages, there is a sleep function, but ?sleep references a data set. And ?pause and ?wait don't exist.

The intended purpose is for self-timed animations. The desired solution works without asking for user input.

@Ricardo, we had a whole discussion on this with Joshua and others and we finally agreed that both "pause" and "sleep" should be in the title. The final title was result of a compromise. And you just step in and *without any argument why your title is better* rollback to previous revision? Adding "sleep" to the title makes the question much easier to find, because "sleep" is in many languages and there is a high probability that users will search for it. Current title contains a lot of word balast and the important keyword is missing. *What was the purpose of your rollback?* — Tomas, Jul 22 '13 at 05:29

score 173 · Accepted Answer · edited Jul 21 '13 at 20:00

173

See help(Sys.sleep).

For example, from ?Sys.sleep

testit <- function(x)
{
    p1 <- proc.time()
    Sys.sleep(x)
    proc.time() - p1 # The cpu usage should be negligible
}
testit(3.7)

Yielding

> testit(3.7)
   user  system elapsed 
  0.000   0.000   3.704

edited Jul 21 '13 at 20:00

Gavin Simpson

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answered Jul 23 '09 at 22:24

Dirk Eddelbuettel

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1

Here's the example code from that page. To pause for 3.7 seconds testit – Dan Goldstein Jul 23 '09 at 22:29
21

By the way, help.search("sleep") would have directed you that way. – Dirk Eddelbuettel Jul 23 '09 at 22:51
Why you cannot do just `Sys.sleep(10)`? – Léo Léopold Hertz 준영 Nov 10 '16 at 14:46
I think you misunderstand my example and illustration which _also measures and hence demonstrates_ exactly that, – Dirk Eddelbuettel Nov 10 '16 at 14:47

score 17 · Answer 2 · answered Nov 01 '17 at 18:08

17

Sys.sleep() will not work if the CPU usage is very high; as in other critical high priority processes are running (in parallel).

This code worked for me. Here I am printing 1 to 1000 at a 2.5 second interval.

for (i in 1:1000)
{
  print(i)
  date_time<-Sys.time()
  while((as.numeric(Sys.time()) - as.numeric(date_time))<2.5){} #dummy while loop
}

answered Nov 01 '17 at 18:08

rbtj

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the Sys.sleep() function did not work in my use case, and this was the only way I was able to manage producing the necessary delay. – Pake Apr 03 '20 at 20:53

How to make execution pause, sleep, wait for X seconds in R?

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