FAQ

If your question isn’t here, ask your own question at the WordPress.org forums. Please do not email or tweet with questions.

How can I move the related posts display?

If you do not want to show the Related Posts display in its default position (right below the post content), first go to YARPP options and turn off the “automatically display” option in the “website” section. If you would like to instead display it in your sidebar and you have a widget-aware theme, YARPP provides a Related Posts widget which you can add under “Appearance” > “Widgets”.

If you would like to add the Related Posts display elsewhere, follow these directions: (Knowledge of PHP and familiarity with editing your WordPress theme files is required.)

Edit your relevant theme file (most likely something like single.php) and add the PHP code related_posts(); within The Loop where you want to display the related posts.

This method can also be used to display YARPP on pages other than single-post displays, such as on archive pages. There is a little more information on the advanced manual installation page.

Does YARPP slow down my blog/server?

A little bit, yes. However, YARPP 3.0 introduced a new caching mechanism which greatly reduces the hit of the computationally intensive relatedness computation. In addition, I highly recommend all YARPP users use a page-caching plugin, such as WP-SuperCache.

If you find that the YARPP database calls are still too database-intensive, try the following:

• turning off “cross relate posts and pages”;
• turning on “show only previous posts”;
• not considering tags and/or categories in the Relatedness formula;
• not excluding any tags and/or categories in The Pool.

All of these can improve database performance.

If you are in the process of looking for a hosting provider whose databases will not balk under YARPP, I personally have had great success with MediaTemple.

Every page just says “no related posts”! What’s up with that?

Most likely you have “no related posts” right now as the default “match threshold” is too high. Here’s what I recommend to find an appropriate match threshold: first, lower your match threshold in the YARPP prefs to something very low, like 1. Most likely the really low threshold will pull up many posts that aren’t actually related (false positives), so look at some of your posts’ related posts and their match scores. This will help you find an appropriate threshold. You want it lower than what you have now, but high enough so it doesn’t have many false positives.

How do I turn off the match score next to the related posts?

The match score display is only for administrators… you can log out of wp-admin and check out the post again and you will see that the score is gone.

If you would like more flexibility in changing the display of your related posts, please see the templating tutorial.

I use DISQUS for comments. I can’t access the YARPP options page!

The DISQUS plugin loads some JavaScript voodoo which is interacting in weird ways with the AJAX in YARPP’s options page. You can fix this by going to the DISQUS plugin advanced settings and turning on the “Check this if you have a problem with comment counts not showing on permalinks” option.

I use DISQUS for comments. My RSS feed is now invalid and cannot be parsed by some clients!

The DISQUS plugin loads some JavaScript voodoo when related posts are displayed, even in the RSS feed. You can fix this by going to the DISQUS plugin advanced settings and turning on the “Check this if you have a problem with comment counts not showing on permalinks” option.

I get a PHP error saying “Cannot redeclare related_posts()“

You most likely have another related posts plugin activated at the same time. Please disactivate those other plugins first before using YARPP.

I turned off one of the relatedness criteria (titles, bodies, tags, or categories) and now every page says “no related posts”!

This has to do with the way the “match score” is computed. Every entry’s match score is the weighted sum of its title-score, body-score, tag-score, and category-score. If you turn off one of the relatedness criteria, you will no doubt have to lower your match threshold to get the same number of related entries to show up. Alternatively, you can consider one of the other criteria “with extra weight”.

It is recommended that you tweak your match threshold whenever you make changes to the “makeup” of your match score (i.e., the settings for the titles, bodies, tags, and categories items).

Are there any plugins that are incompatible with YARPP?

Aside from the DISQUS plugin (see above), currently the only known incompatibility is with the SEO_Pager plugin and the Pagebar 2 plugin. Users of SEO Pager are urged to turn off the automatic display option in SEO Pager and instead add the code manually. There are reports that the WP Contact Form III plugin and Contact Form Plugin may also be incompatible with YARPP. Other related posts plugins, obviously, may also be incompatible.

Please submit similar bugs by starting a new thread on the WordPress.org forums. I check the forums regularly and will try to release a quick bugfix.

Does YARPP work with full-width characters or languages that don’t use spaces between words?

YARPP works fine with full-width (double-byte) characters, assuming your WordPress database is set up with Unicode support. 99% of the time, if you’re able to write blog posts with full-width characters and they’re displayed correctly, YARPP will work on your blog.

However, YARPP does have difficulty with languages that don’t place spaces between words (Chinese, Japanese, etc.). For these languages, the “consider body” and “consider titles” options in the “Relatedness options” may not be very helpful. Using only tags and categories may work better for these languages.

Things are weird after I upgraded.

I highly recommend you disactivate YARPP, replace it with the new one, and then reactivate it.

Can I clear my cache?

Yes, you can clear the cache by going to your YARPP settings page (“Related Posts (YARPP)”) in your admin interface, and adding &action=flush to the URL and reloading the page. YARPP will begin the process of organically rebuilding your cache.