title: adding array (list of values) to a json object
body: <p>I try to loop through some json (clustered twees from twitter) and count how often particular keywords (hashtags) are present so I can create an ordered list of frequent words. <br />
  this (19)<br />
  that (9)<br />
  hat (3)<br /></p>
  
  <p>this I've done by creating </p>
  
  <pre><code>var hashtags = [];  
  </code></pre>
  
  <p>first time I add a new word i add th word and give the value 1</p>
  
  <pre><code>hashtags[new_tag] = 1;
  </code></pre>
  
  <p>the next time a find the same worj I just add to the number</p>
  
  <pre><code>hashtags[hashtag]+=1;
  </code></pre>
  
  <p>the result is a simple structure with words and values. I can list out what I need with</p>
  
  <pre><code>$.each(hashtags, function(i, val){
      console.log(i+ " - "+ val);
  })
  </code></pre>
  
  <p>Now I realize I also nee to know what clusters these words where found in. So; I thing I need to add a list (array) to my "hashtags".</p>
  
  <p>I guess what I try to create is a json structure like this:</p>
  
  <pre><code>hashtags: {"this": 19, clusters: [1,3,8]},{"that": 9, clusters: [1,2]}
  </code></pre>
  
  <p>How do I add the arrays to the hashtags object?</p>