title: Rails use associated record to group array results
body: <p>In my application I have</p>
  
  <pre><code>class Volunteer &lt; ActiveRecord::Base
    has_many :reports
  end
  
  class Report &lt; ActiveRecord::Base
    belongs_to :volunteer
  end
  </code></pre>
  
  <p>each volunteer has a field which stores the category that volunteer is apart of (director, supervisor, general)</p>
  
  <p>Im using a simple search form to grab all reports within a specific time period, and I would like to split the results into three separate arrays by Volunteer.category .  </p>
  
  <p>What would be the best way to split out the results while in the controller?</p>