title: How to get the intersection of two jquery objects
body: <p>I have a number of elements with the following markup:</p>
  
  <pre><code>&lt;div id="div1" data-category="mycategory" data-feature="myfeature"&gt;&lt;/div&gt;
  &lt;div id="div2" data-category="anothercategory" data-feature="myfeature"&gt;&lt;/div&gt;
  &lt;div id="div3" data-category="mycategory" data-feature="myfeature"&gt;&lt;/div&gt;
  &lt;div id="div4" data-category="mycategory" data-feature="anotherfeature"&gt;&lt;/div&gt;
  </code></pre>
  
  <p>And two jQuery selectors that reference these:</p>
  
  <pre><code>$cats = $('div[data-category="mycategory"]');
  $features = $('div[data-features="myfeature"]');
  </code></pre>
  
  <p>How do I merge these two <em>selectors</em> into one where BOTH references are true? I want to end up with a selector that only contains div's 1 and 3 but using the already existing $cats and $features - not build another selector based on markup</p>