title: Vector declaration "expected parameter declarator"
body: <p>I have a line of code inside a class's private member variables:</p>
  
  <pre><code>vector&lt;double&gt; dQdt(3)
  </code></pre>
  
  <p>When compiling in xcode, this gives an error "expected parameter declarator." I think I provided sufficient info. I don't see anything wrong with this declaration. </p>