XPath, Xml e php

Per lavorare con xpath e usare una risorsa esterna


$sxmltxt=file_get_contents('http://miourl.com');
$sxmltxt=str_replace("xmlns=","a=",$sxmltxt);
$xmltxt=simplexml_load_string($sxmltxt);
$zones = (array)$xmltxt->xpath('/zones_users/zone[@id=1]');
foreach($zones as $zone) {
if ($zone->day['id'] == ($day_of_week+1) ) {
echo $zone->day['count'];
//break;
}
}