<?php   /////   xslProc.php    /////
$transform="catalogOLfrag_output.xsl";
$xmlsource="catalog_frag_output.xml";

// $transform="param.xsl";
// $xmlsource="catalog.xml";

if (file_exists($xmlsource)) 
{  $xml = simplexml_load_file($xmlsource); }
if (file_exists($transform)) 
{  $xsl = simplexml_load_file($transform); }
if ( $xsl && $xml )
{  $xslt = new XsltProcessor();
   $xslt->importStylesheet($xsl);
   $xslt->setParameter("", 'semester', 'Spring');
   if ($result = $xslt->transformToXML($xml))
   {  echo $result; } 
   else 
   { trigger_error('XSL transformation failed.', E_USER_ERROR);
   } // if
}
?>