General Support: Fatal error - please help

I am trying to integrate supersized image slideshow into my plogger page and have put together the following code to get the pictures into the slideshow.php file.


<?php if (plogger_has_pictures()) : ?>

<?php while(plogger_has_pictures()) : plogger_load_picture();?>


<img src="<?php echo plogger_get_picture_thumb(THUMB_LARGE);?>" title="<?php echo plogger_get_picture_caption(); ?>" />


<?php endwhile; ?>

<?php else : ?>
<div id="no-pictures-msg">
<h2><?php echo plog_tr('No Images') ?></h2>
<p><?php echo plog_tr('Sorry, but there are no images in this album yet.') ?></p>
</div><!-- /no-pictures-msg -->
<?php endif; ?>

I striped this from album.php as it does what I need.
The problem is I am getting a fatal error which reads "Call to undefined function: plogger_has_pictures()"

I am sill not clear as to how plogger works (php) so I don't know how to call the function before it loads.

Can anyone please explain what is wrong here or point me in the right direction to some documentation.

Thanks