- var_dump: documentation ( source)
- arsort: documentation ( source)
<?php
$events = array();
$events['event'][] = array(-1 => 'e');
$events['event'][] = array(1 => 'b');
$events['event'][] = array(-20 => 'b');
$toSort = $events['event'];
arsort($toSort);
var_dump($toSort);
?>