MODX Revolution Star Rating top star elements

showtopstar.php

<?php
$snippetPath = $modx->getOption('core_path').'components/star_rating/';
$modx->addPackage('star_rating',$snippetPath.'model/');
$c = $modx->newQuery('starRating');
$c->sortby('vote_total','DESC');
$c->sortby('vote_count','DESC');
$c->limit('100');
$c->prepare();
$c->stmt->execute();
$res = $c->stmt->fetchAll(PDO::FETCH_ASSOC);
foreach ($res as $v) {
    $output.= $v['starRating_id'].",";
}; 
$output = substr($output,0,-1);
return $output;