Group these records by groupId in a separate div

Hi Folks, I really hope that someone out there can help me..

Here is my problem:

I'm trying to setup my site using joomla, but had to dig into the code to make some modifications myself.

I have a component where I display some categories with links to articles like this:

<?php foreach($this->list as $l): ?>
  <li class="article-intro-list">
    <h3 class="article-title"><a href="<?php echo $l->link; ?>" ><?php echo $l->title; ?></a><span>+</span></h3>
    <div class="collapse"> <?php echo $l->description; ?>
      <div class="loadPopUp"><a href="<?php echo $l->link; ?>" title="<?php echo $l->title; ?>" class="mb" rel="width:730,height:500"><span class="howdoi_icon"><img src="images/more.gif" alt="Read more" /></span> Read more...</a></div>
    </div>
  </li>
   <?php endforeach; ?>

PHP:

What this list array contains is also a reference to a groupId of the category, which can be retrieved simply by:

<?php echo $l->groupId; ?>

PHP:

And also the group title by:

<?php echo $l->groupTitle; ?>

PHP:

I would like to group these categories by their groupId into a separate div with a title for each group.
I really can't figure out that... although it seems pretty straightforward... Still not so good in php

Thanks so much in advance!

 

There may be a better way to do it, but this was my first though:

// Generate groups array where array key is groupId
$groups = array();
foreach ($this->list as $l) $groups[$l->groupId][] = $l;

// Go through groups array, use first record in array to fetch group title
foreach ($groups as $group)
{
	echo '<div><b>'.$group[0]->groupTitle.':</b> ';
	foreach ($group as $item) echo $item->title .' ';
	echo '</div>';
}

PHP: