On Thu, Jun 27, 2013 at 1:16 AM, Rotwang <sg...@hotmail.co.uk> wrote:
> On 25/06/2013 23:57, Chris Angelico wrote:
>>
>> On Wed, Jun 26, 2013 at 8:38 AM, Mark Janssen <dreamingforw...@gmail.com>
>> wrote:
>>>
>>> Combining integers with sets I can make
>>> a Rational class and have infinite-precision arithmetic, for example.
>>
>>
>> Combining two integers lets you make a Rational. Python integers are
>>
>> already infinite-precision. Or are you actually talking of using
>> "machine words" and sets as your fundamental? Also, you need an
>>
>> ordered set - is the set {5,3} greater or less than the set {2} when
>> you interpret them as rationals? One must assume, I suppose, that any
>>
>> one-element set represents the integer 1, because any number divided
>> by itself is 1. Is the first operand 3/5 or 5/3?
>
>
> You could use Kuratowski ordered pairs:
>
> http://en.wikipedia.org/wiki/Ordered_pair#Kuratowski_definition
>
> Not that doing so would be sensible, of course. I don't know much about
> low-level data structures but it seems obvious that it's much easier to
> implement an ordered container type than an unordered set on a computer.Yeah, I don't think Mark is much concerned about implementing things on actual computers, somehow :) ChrisA -- http://mail.python.org/mailman/listinfo/python-list
