Time out an R command via something like try()

Question

I'm running a large number of iterations in parallel. Certain iterates take much (say 100x) longer than others. I want to time these out, but I'd rather not have to dig into the C code behind the function (call it fun.c) doing the heavy lifting. I am hoping there is something similar to try() but with a time.out option. Then I could do something like:

for (i in 1:1000) {
    try(fun.c(args),time.out=60))->to.return[i]
}

So if fun.c took longer than 60 seconds for a certain iterate, then the revamped try() function would just kill it and return a warning or something along those lines.

Anybody have any advice? Thanks in advance.

Answer 1

See this thread: http://r.789695.n4.nabble.com/Time-out-for-a-R-Function-td3075686.html

and ?evalWithTimeout in the R.utils package.

Here's an example:

require(R.utils)

## function that can take a long time
fn1 <- function(x)
{
    for (i in 1:x^x)
    {
        rep(x, 1000)
    }
    return("finished")
}

## test timeout
evalWithTimeout(fn1(3), timeout = 1, onTimeout = "error") # should be fine
evalWithTimeout(fn1(8), timeout = 1, onTimeout = "error") # should timeout