(From: http://paddy3118.blogspot.com/2008/09/python-fractions-issue.html)
There seems to be a problem/difference in calculating with the new fractions module when comparing Python 26rc2 and 30rc1 I was reading the paper "Interval Arithmetic: Python Implementation and Applications" and thought to try the first example function f(x,y), which needs more precision than Python floating point provides (on my Windows PC), to calculate a sensible answer. Ahah, I thought, lets try this with Fractions - so I first installed Python 30rc1, typed in the Function - saw the rubbish result, then used Fractions and got the 'right' result. I then wondered if fractions had been back-ported to Python 2.6rc2, found that it had, but got different results. As you can see from the table, Python 2.6rc2 has a problem calculating t3 = F(11,2) * y**8 + x/(2*y), where F is Fraction. I wonder where the problem lies? (For the Table, please see the blog entry). - Paddy. -- http://mail.python.org/mailman/listinfo/python-list
