protected function microtime($microtime = null)
    {
        list($usec, $sec) = explode(" ", $microtime ?: microtime());
        return (float)$usec + (float)$sec;
    }
protected function microtime($microtime = null)
    {
        list($usec, $sec) = explode(" ", $microtime ?: microtime());
        return (float)$usec + (float)$sec;
    }
protected function microtime ( $ microtime = null ) { list ( $ usec , $ sec ) = explode ( " " , $ microtime ? : microtime ( ) ) ; return ( float ) $ usec + ( float ) $ sec ; }
Returns a microtime.
@param int|null $microtime
@return float
Returns a microtime .