note 93828 added to function.microtime

Another version of a stopwatch-style function, this one with the following features: - Can evaluate any function (callback) with any arbitrary arguments - Can specify the # of iterations to run The obvious caveat is of course to take the return value with a grain of salt, especially since this one doesn't run in the tightest loop possible. A little eval() work could probably fix that, but in the meantime calling this function with no arguments will make it establish a reference point (using pi() ) to measure subsequent calls against -- sort of like hitting the "zero" button on a food scale. <?php function stopwatch() // stopwatch([$limit], [$callback], [$args ... ]) // $limit - # of iterations to run // $callback - function to time // $args - arguments for function // { static $zero = 0; static $limit = 99999; $args = func_get_args() + Array(null); // Check for # iterations, assign for future calls if (is_integer($args[0])) $max = min(array_shift($args), 999999); else $max = $limit; if ($max != $limit) { $limit = $max; $zero = 0; } if (isset($args[0])) $callback = array_shift($args); else $callback = null; if (is_null($callback)) { // Use a very small function as a reference point $callback = 'pi'; $zero = null; } // Ensure a valid callback if (!is_callable($callback, false, $name)) return null; if ($name == __FUNCTION__) return null; // The actual loop $st = explode(' ',microtime()); for($cx=0; $cx<$max; $cx++) { call_user_func_array($callback, $args); } // Final calculations $t = explode(' ', microtime()); $t[0] -= $st[0]; $t[1] -= $st[1]; if (is_array($zero)) // Use previous reference point { $t[0] -= $zero[0]; $t[1] -= $zero[1]; } elseif (is_null($zero)) // or establish a new one { $zero = $t; return; } if ($t[0] < 0) // Ensure microseconds are always positive { $t[0]++; $t[1]--; } // Done return "$t[1] + $t[0]s"; } function faster() { return; } function slower() { return fmod(5,2); } echo "<p>Comparing two functions...</p>"; var_dump(stopwatch('faster')); var_dump(stopwatch('slower')); echo "<p>Comparing 100,000 iterations of two functions..."; var_dump(stopwatch(100000, 'faster')); var_dump(stopwatch('slower')); echo "<p>Run a single function 500 times...</p>"; var_dump(stopwatch(500)); var_dump(stopwatch('max', 1, 2, 3, 4, 5)); echo "<p>Run a single function 555,555 times...</p>"; var_dump(stopwatch(555555)); var_dump(stopwatch('max', 1, 2, 3, 4, 5)); echo "<p>Fail sanity test...</p>"; var_dump(stopwatch('stopwatch')); // Attempt to time itself! ?> ---- Server IP: 209.41.74.194 Probable Submitter: 67.237.228.46 ---- Manual Page -- http://www.php.net/manual/en/function.microtime.php Edit -- https://master.php.net/note/edit/93828 Del: integrated -- https://master.php.net/note/delete/93828/integrated Del: useless -- https://master.php.net/note/delete/93828/useless Del: bad code -- https://master.php.net/note/delete/93828/bad+code Del: spam -- https://master.php.net/note/delete/93828/spam Del: non-english -- https://master.php.net/note/delete/93828/non-english Del: in docs -- https://master.php.net/note/delete/93828/in+docs Del: other reasons-- https://master.php.net/note/delete/93828 Reject -- https://master.php.net/note/reject/93828 Search -- https://master.php.net/manage/user-notes.php