title: Querying a Dictionary within a Dictionary with LINQ
body: <p>I have a nested Dictionary like this</p>
  
  <pre><code>Dictionary&lt;double, Dictionary&lt;double, List&lt;string&gt;&gt;&gt;
  </code></pre>
  
  <p>With LINQ I would like to</p>
  
  <ol>
  <li><p>Sort the outer Dictionary in descending order, keep the first 20, and work with the inner Dictionary.</p></li>
  <li><p>Sort the inner Dictionary in descending order, keep the sorted <code>List&lt;string&gt;</code> and do operations on these lists of strings.</p></li>
  </ol>
  
  <p>I tried a lot of things without any success.</p>