

   RRuunnnniinngg TTiimmee ooff RR

        proc.time()

   DDeessccrriippttiioonn::

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

   VVaalluuee::

        A numeric vector of length 5, containing the user, sys-
        tem, 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.

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

   SSeeee AAllssoo::

        `system.time' for timing a valid R expression

   EExxaammpplleess::

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

