Show RSS feed items based on other PHP script - php

Question

I want to create an RSS feed in PHP based on other RSS feeds. That works.
But, Now I want to change how many items are shown in the new created feed. This based on calculation of the items of another feed.
I use this script for the calculation, which works fine:
<?php
$url = 'http://www.nu.nl/rss/Algemeen';
$xml = simplexml_load_file($url);
$tags = array();
foreach($xml->channel->item as $item) {
$children = $item->children(); // get all children of each item tag
foreach ($children as $node) {
$tags[] = $node->getName(); // get the node name of each children
}
}
$test = count($tags);
$count = array_count_values($tags); // count the values
?>
<?php
$mystring = count($tags);
$findme = '3';
$pos = strpos($mystyring, $findme);
?>
<?php
$artikel = ($mystring / 5);
echo $artikel;
?>
I use this script, magpierss, fow creating a new feed:
<?php
/**
* Setup
*
*/
$DOMAIN_NAME = 'http://sitename.nl/';
$FEED_URL = $DOMAIN_NAME . 'rss/full.php';
$SITE_TITLE = 'test';
$SITE_DESRIPTION = '-';
$SITE_AUTHOR = 'test2';
$RSS_CACHE = "/tmp/rsscache";
$RSS_CACHE_EXP = 3600;
$FEED_LIST = array(
'http://www.nu.nl/rss/Economie',
'http://www.nu.nl/rss/Internet'
);
/**
* Do not modify below this point
*
*/
define('MAGPIE_CACHE_DIR', $RSS_CACHE);
define('MAGPIE_CACHE_AGE', $RSS_CACHE_EXP);
define('MAGPIE_OUTPUT_ENCODING', 'utf-8');
// include required files
require_once ('magpierss-0.72/rss_fetch.inc');
include ('feedcreator.class.php');
/* Set RSS properties */
$rss = new UniversalFeedCreator();
$rss->useCached();
$rss->title = $SITE_TITLE;
$rss->description = $SITE_DESRIPTION;
$rss->link = $DOMAIN_NAME;
$rss->syndicationURL = $FEED_URL;
$rss->encoding = 'utf8';
/* Set Image properties
$image = new FeedImage();
$image->title = $SITE_TITLE . " Logo";
$image->url = $SITE_LOG_URL;
$image->link = $DOMAIN_NAME;
$image->description = "Feed provided by " . $SITE_TITLE . ". Click to visit.";
$rss->image = $image;
*/
function showSummary($url, $num = 10, $showfullfeed = false) {
global $rss, $DOMAIN_NAME, $SITE_AUTHOR, $SITE_TITLE;
$num_items = $num;
# $rss1 = fetch_rss($url);
if ($rss1) {
$items = array_slice($rss1->items, 0, $num_items);
foreach ($items as $item) {
$href = $item['link'];
$title = $item['title'];
if (!$showfullfeed) {
$desc = $item['description'];
} else {
$desc = $item['content']['encoded'];
}
// $desc .= '
//Copyright © '.$SITE_TITLE.'. All Rights Reserved.
//';
$pdate = $item['pubdate'];
$rss_item = new FeedItem();
$rss_item->title = $item['title'];
$rss_item->link = $item['link'];
$rss_item->description = $item['content']['encoded'];
$rss_item->date = $item['pubdate'];
$rss_item->source = $DOMAIN_NAME;
$rss_item->author = $SITE_AUTHOR;
$rss->addItem($rss_item);
}
} else {
echo "Error: Cannot fetch feed url - " . $url;
}
}
// Fetch all feeds
foreach($FEED_LIST as $v) showSummary($v);
// Sort items by date
function __usort($ad, $bd) {return strtotime($bd->date) - strtotime($ad->date);}
usort($rss->items, '__usort');
// Display items
$rss->saveFeed("RSS1.0", $RSS_CACHE . "/feed.xml");
How could I let the variable $artikel decide how many items are showed in the feed?