note 50962 deleted from function.microtime by tularis
| From: | tularis@php.net | Date: | Sun, 22 Jun 2008 12:15:36 +0000 |
| Subject: | note 50962 deleted from function.microtime by tularis | ||
| References: | 1 | Groups: | php.notes |
| Request: | Send a blank email to php-notes+get-140707@lists.php.net to get a copy of this message | ||
Note Submitter: edwardzyang at thewritingpot dot com
----
Here is a modified version of the chronometer functions. It acts like a "lap watch",
immediately starting another timing session right after you call it. It also lets you specify the
return value to be in seconds or in milliseconds: this is useful when a microsecond() timing would
return a negative value.
<?php
/*
* Slightly modified from http://www.php.net/manual/en/function.microtime.php,
adds
* support for Second values (as microtime can cause problems when you run extended loops).
* It also is "unstopped" timing, that is, the timer never sleeps.
*/
$CHRONO_STARTTIME = 0;
define("RET_TIME", "ms"); //Can be set to "ms" for milliseconds
or "s" for seconds
function chronometer()
{
global $CHRONO_STARTTIME;
$now = microtime(TRUE); // float, in _seconds_
if (RET_TIME === 's') {
$now = $now + time();
$malt = 1;
$round = 7;
} elseif (RET_TIME === 'ms') {
$malt = 1000;
$round = 3;
} else {
die("Unsupported RET_TIME value");
}
if ($CHRONO_STARTTIME > 0) {
/* Stop the chronometer : return the amount of time since it was started,
in ms with a precision of 3 decimal places, and reset the start time.
We could factor the multiplication by 1000 (which converts seconds
into milliseconds) to save memory, but considering that floats can
reach e+308 but only carry 14 decimals, this is certainly more precise */
$retElapsed = round($now * $malt - $CHRONO_STARTTIME * $malt, $round);
$CHRONO_STARTTIME = $now;
return $retElapsed;
} else {
// Start the chronometer : save the starting time
$CHRONO_STARTTIME = $now;
return 0;
}
}
?>
It can be used like this:
<?php
chronometer();
//Do stuff;
echo chronometer(); //this will return the time taken to "Do stuff"
//Do more stuff
echo chronometer(); //this will return the time taken to "Do more stuff"
?>