title: Find minimum values in a python 3.3 list
body: <p>For example:</p>
  
  <pre><code>a=[-5,-3,-1,1,3,5]
  </code></pre>
  
  <p>I want to find a negative and a positive minimum.</p>
  
  <p>example:
  negative</p>
  
  <pre><code>print(min(a)) = -5 
  </code></pre>
  
  <p>positive</p>
  
  <pre><code>print(min(a)) = 1
  </code></pre>