Zend framework installation status

Hi All,

I don't know more about zendwork, I want to know that how can ckeck whether zend frame installed in my machine or not?(I have installed php 5 ), when i try to execute following code

<?php
if (zend_initialize('Zend_Gdata')) {
   $gdata = new Zend_Gdata();
   $gdata->doStuff();
}
else {
  echo 'Zend GData not available!';
}
?>

I got the error
Fatal error: Call to undefined function zend_initialize() in C:\wamp\www\youtube\gdata.php on line 2

Please help me!!!!