Running Time of R

Description

proc.time determines how much time (in seconds) the currently running R process already consumed.

Usage

proc.time()

Value

A numeric vector of length 5, containing the user, system, and total elapsed times for the currently running R process, and the cumulative sum of user and system times of any child processes spawned by it.

The resolution of the times will be system-specific; it is common for them to be recorded to of the order of 1/100 second, and elapsed time is rounded to the nearest 1/100.

It is most useful for ``timing'' the evaluation of R expressions, which can be done conveniently with system.time.

Note

CPU times will be returned as NA on Windows 9x systems, but are genuine times on NT4 and 2000 systems. Times of child processes are not available and will always be given as NA.

See Also

system.time for timing a valid R expression.

Examples

ptm <- proc.time()
for (i in 1:50) mad(runif(500))
proc.time() - ptm