title: Split array up into n-groups of m size?
body: <blockquote>
    <p><strong>Possible Duplicate:</strong><br>
    <a href="https://stackoverflow.com/questions/3864139/need-to-split-arrays-to-sub-arrays-of-specified-size-in-ruby">Need to split arrays to sub arrays of specified size in Ruby</a>  </p>
  </blockquote>
  
  
  
  <p>I'm looking to take an array---say [0,5,3,8,21,7,2] for example---and produce an array of arrays, split every so many places.  If the above array were set to a, then</p>
  
  <pre><code>a.split_every(3)
  </code></pre>
  
  <p>would return [[0,5,3],[8,21,7][2]]</p>
  
  <p>Does this exist, or do I have to implement it myself?</p>