Truncate the blog “post_content” to 30 words?

I have a external php page that grabs my wordpress blog content. I would like to know if there is a way to truncate the blog content to 30 words?

Here is my php code that works (but does not truncate content):
<?php
/* PHP to pull and publish wordpress 2 post data on an external page NO CACHE*/
define(‘WP_USE_THEMES’, false);
require(‘blog/wp-blog-header.php’);

$how_many=1; //How many posts do you want to show
require_once(“blog/wp-config.php”);
// strip out html characters to allow for truncating
$strippedDesc = strip_tags($desc);
// truncate post content to 12 words
$numwords = 12;
preg_match(“/([\S]+\s*){0,$numwords}/”, $strippedDesc, $regs);
$shortDesc = trim($regs[0]);
// Change this for your path to wp-config.php file

$news=$wpdb->get_results(“SELECT ID,post_title,
post_content FROM $wpdb->posts
WHERE post_status= \”publish\”
ORDER BY ‘ID’ DESC LIMIT “.$how_many);
foreach($news as $np){

//NOTE: get other post data by selecting different
//data in the posts table…

$permalink=get_permalink($np->ID);

$html= “<p><a href=\””. $permalink .
“\”>$np->post_title

$np->post_content\n</p>”;

//NOTE: you can easily alter the HTML above to suit

echo $html;

}
?>