Fran?ois Pinard <pinard at iro.umontreal.ca> writes:
Hi, people. A tiny suggestion for the system.time function.
Could the returned vector have names? These could be like:
c("User", "System", "Elapsed", "Sub.User", "Sub.System")
That would then produce self-documenting output.
Here's a function you could try. It names the result as you
suggested. It also can be nested, which system.time cannot, because
it uses on.exit without specifying add=TRUE.
timeit <- function (expr, gcFirst = TRUE)
{
nms <- c("User", "System", "Elapsed", "Sub.User", "Sub.System")
if (!exists("proc.time")) {
ans <- rep(as.numeric(NA), 5)
names(ans) <- nms
return(ans)
}
loc.frame <- parent.frame()
if (gcFirst)
gc(FALSE)
expr <- substitute(expr)
time <- proc.time()
show_time <- function() {
t <- proc.time() - time
names(t) <- nms
cat("Timing stopped at:\n")
print(t)
t
}
tryCatch(eval(expr, envir = loc.frame),
error=function(e) {
msg <- paste("Error in", deparse(conditionCall(e)),
":", conditionMessage(e), "\n")
cat(msg)
})
show_time()
}
## Examples
t <- timeit(z <- rnorm(10000))
Timing stopped at:
User System Elapsed Sub.User Sub.System
0.007 0.001 0.008 0.000 0.000
t
User System Elapsed Sub.User Sub.System
0.007 0.001 0.008 0.000 0.000
## Nested calls. I dunno, could be useful in some debugging
## situations *shrug*
t <- timeit({z <- rnorm(10000);timeit(q <- runif(50000))})
Timing stopped at:
User System Elapsed Sub.User Sub.System
0.012 0.002 0.014 0.000 0.000
Timing stopped at:
User System Elapsed Sub.User Sub.System
0.090 0.003 0.146 0.000 0.000
t
User System Elapsed Sub.User Sub.System
0.090 0.003 0.146 0.000 0.000
## With an error
t <- timeit(plot(foobarbaz))
Error in plot(foobarbaz) : object "foobarbaz" not found
Timing stopped at:
User System Elapsed Sub.User Sub.System
0.002 0.000 0.038 0.000 0.000
t
User System Elapsed Sub.User Sub.System
0.002 0.000 0.038 0.000 0.000