echoz

This plugin provides functions to retrieve the parent category of any particular post should it be assigned to a sub category of that parent category.
Using this feature, the plugin is also able to modify the WordPress Loop to redirect any category page generation to the parent category. This is especially useful when theme developers want to be able to specify category-x.php templates and have all related posts, be it those assigned to the category or the sub categories use that template for page generation.
So for example the current category structure is as follows.
<ul>
<li>Main Category (has category-x.php template)
<ul>
<li>Sub Category 1</li>
<li>Sub Category 2</li>
</ul>
</li>
</ul>
A post is assigned to “Sub Category 2”.
When the post is requested the plugin will automatically detect if it has a parent category. If so, it will modify the WP variables to set the current category as the parent category and add a new variable stating the actual category of the post. This affects the WordPress Loop to category-x.php template defined for the parent
<h3>Usable Commands for Theme Developers</h3>
The PHP commands for theme developers to use are pretty straight forward.
get_category_child() returns the current post child category ID.
is_parent() checks if the current post is at the parent category.
get_category_title($id) gets the title of the category that is $id.
get_category_parent() returns the current post’s parent category ID.

Elevate Parent Category Template

Elevates parent category template to top of WordPress Loop.

lyzadanger

Lyza Loop is a WordPress plugin for theme developers and template-savvy folks that aims to:
<ul>
<li>Dramatically shorten the time required to code custom loops</li>
<li>Modularize custom loop markup using what I hope is a straightforward templating process</li>
<li>Provide convenient batching variables</li>
<li>Respect the context in which the custom loop is called and put everything back the way it was (e.g. global $wp_query and $post objects)</li>
<li>Reduce tedious and duplicated code for custom loops</li>
</ul>
There are two parts to the <code>lyza_loop()</code> function:
<ol>
<li>Finding posts (or pages): extending <code>query_posts()</code> — <code>lyza_loop()</code> takes any argument WordPress’ own query_posts() takes</li>
<li>Rendering relevant posts or pages: using “loop templates.” A loop template is a PHP file with markup (and logic) you’d like to use for each post/page in the loop.</li>
</ol>
Read more on the <a href="http://www.lyza.com/lyza-loop" title="Lyza Loop WordPress plugin home and documentation" rel="nofollow ugc">plugin home page</a>

Lyza Loop

Quickly code custom loops with re-usable templates and useful variables. Easier custom loops for theme developers.

Elevate Parent Category Template vs Lyza Loop