title: Erlang case statement
body: <p>I have the following Erlang code and it is giving the warning as follows, when i try to compile it, but that make sense. function need two arguments, but i need to patten match "everything else" rather x, y or z.</p>
  
  <pre><code>-module(crop).
  -export([fall_velocity/2]).
  
  fall_velocity(P, D) when D &gt;= 0 -&gt;
  case P of
  x -&gt; math:sqrt(2 * 9.8 * D);
  y -&gt; math:sqrt(2 * 1.6 * D);
  z -&gt; math:sqrt(2 * 3.71 * D);
  (_)-&gt; io:format("no match:~p~n")
  end.
  
  crop.erl:9: Warning: wrong number of arguments in format call. 
  </code></pre>
  
  <p>I was trying an anonymous variable after io:format, but still it is not happy.</p>