ndicating whether each element of the array is missing
(that is, undefined).
</p>
<p>This is a planar property.
</p>
</dd></dl>

<dl class="first-deftypecv first-deftypeivar-alias-first-deftypecv">
<dt class="deftypecv deftypeivar-alias-deftypecv" id="index-cats-of-categorical"><span class="category-def">Instance Variable of <code class="code">categorical</code>: </span><span><code class="def-type"><code class="code">cellstr</code></code> <strong class="def-name">cats</strong><a class="copiable-link" href="