CODEWITHSUNDEEP
r
inscaven
inscaven

Reputation: 2584

For loop with step execution time restriction

I want to make a restriction on execution time for every step of the for loop. Simply, if the step didn't complete in 10 seconds, then go next.

To be more specific, here is some code.

myComplicatedFunction <- function(obj, ...) { <some code here> }
x # something to process
x_result <- vector(mode = "list", length = length(x))
for (i in seq_along(x)) {
    x_result[[i]] <- 
        processNotMoreThanXSeconds(
            givenTime = 10,
            myComplicatedFunction(x[i]),
            didNotComplete = function() "Time's up!"
        )
}

My question is, how to declare such function processNotMoreThanXSeconds?

Upvotes: 3

Views: 91

Answers (1)

LyzandeR
LyzandeR

Reputation: 37879

You can use setTimeLimit (it is part of base R):

setTimeLimit({

  Sys.sleep(7)

}, elapsed = 5)

If the time limit is reached the function will return an error (like if you run the above, processing takes 7 secs but the limit is 5). You can tie this up with try in order to handle the error and continue the loop:

myerror <- try({

   setTimeLimit({

     Sys.sleep(7)

   }, elapsed = 5)
}, silent = TRUE)

class(myerror)
#[1] "try-error"

Then use an if-else statement to check if there was an error and continue. Something like:

if (class(myerror) == 'try-error') {
  next
}

Upvotes: 6

Related Questions