Only show certain rss feeds

I am showing a feed for all categories and sub-categories. Is there a way to only show the parent category or selected categories?

<?php
$myitem ='';
$mycats=  get_categories();
foreach($mycats as $mycat) {
	$myitem = '<li><a title="Subscribe to the '.$mycat->name.' news feed" href="'.get_bloginfo('url').'/category/'.$mycat->category_nicename.'/feed/">'.$mycat->name.'</a></li>';
	echo $myitem;
}
?>

Use RSS Channel Writer to solve this problem.

I don’t believe I need to buy a piece of software to do this.

Thanks for your suggestion though.

Just had to dig a little deeper into the codex to get the top level (parent) categories only.

This works:

<?php
$myitem ='';
$mycats=  get_categories('include=3,4,5,6,8,9,16');
foreach($mycats as $mycat) {
	$myitem = '<li><a title="Subscribe to the '.$mycat->name.' news feed" href="'.get_bloginfo('url').'/category/'.$mycat->category_nicename.'/feed/">'.$mycat->name.'</a></li>';
	echo $myitem;
}
?>

exclude=‘’ also works, to exclude child categories.