title: Looping through an array with step
body: <p>I want to look at every n-th elements in an array. In C++, I'd do this:</p>
  
  <pre><code>for(int x = 0; x&lt;cx; x+=n){
      value_i_care_about = array[x];
      //do something with the value I care about.  
  }
  </code></pre>
  
  <p>I want to do the same in Ruby, but can't find a way to "step". A <code>while</code> loop could do the job, but I find it distasteful using it for a known size, and expect there to be a better (more Ruby) way of doing this.</p>