title: Enumerable.Except Problem
body: <p>Can someone explain why this doesn't work like I think it should.</p>
  
  <pre><code>double[] numbers1 = { 2.0, 2.1, 2.2, 2.3, 2.3, 2.3, 2.4, 2.5 };
  double[] numbers2 = { 2.2 };
  
  IEnumerable&lt;double&gt; onlyInFirstSet = numbers1.Except(numbers2);
  
  foreach (double number in onlyInFirstSet)
      Console.WriteLine(number);
  
  /*
   This code produces the following output:
  
   2
   2.1
   2.3
   2.4
   2.5
  */
  </code></pre>
  
  <p>What I would expect is 2, 2.1, 2.3, 2.3, 2.3, 2.4, 2.5. Why would except return a distinct list? Is this a bug?</p>
  
  <p>Update:</p>
  
  <p>Ok, totally missed that point in the docs. Funny 4 people respond with the same answer. You would think you would just up vote the guy who answered it first.:)</p>