title: Is there an implementation of _rational_ interval arithmetic in Python?
body: <p>Is there an implementation of <em>rational</em> interval arithmetic in Python?  <a href="http://pyinterval.googlecode.com/svn/trunk/html/index.html" rel="nofollow">This</a> uses floats, not rationals.</p>
  
  <p>If not, is there any implementation of rationals in Python that includes ±∞ ?</p>