[Haskell-cafe] Mystery of an Eq instance

[David Thomas]

Sure.  An interesting, if not terribly relevant, fact is that there are
more irrational numbers that we *can't* represent the above way than that
we can (IIRC).

However, those aren't actually interesting in solving the kinds of problems
we want to solve with a programming language, so it's academic, and
symbolic representation certainly gains you some things and costs you some
things in meaningful engineering kinds of ways.


On Sat, Sep 21, 2013 at 9:41 AM, Brandon Allbery <allbery.b at gmail.com>wrote:

> On Sat, Sep 21, 2013 at 12:35 PM, Bardur Arantsson <spam at scientician.net>wrote:
>
>> On 2013-09-20 18:31, Brandon Allbery wrote:
>> [--snip--]
>> > unless you have a very clever representation that can store
>> > in terms of some operation like sin(x) or ln(x).)
>>
>> I may just be hallucinating, but I think this is called "describable
>> numbers", i.e. numbers which can described by some (finite) formula.
>>
>> Not sure how useful they would be in practice, though :).
>>
>
> I was actually reaching toward a more symbolic representation, like what
> Mathematica uses.
>
> --
> brandon s allbery kf8nh                               sine nomine
> associates
> allbery.b at gmail.com
> ballbery at sinenomine.net
> unix, openafs, kerberos, infrastructure, xmonad
> http://sinenomine.net
>
> _______________________________________________
> Haskell-Cafe mailing list
> Haskell-Cafe at haskell.org
> http://www.haskell.org/mailman/listinfo/haskell-cafe
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.haskell.org/pipermail/haskell-cafe/attachments/20130921/a9b783f1/attachment.htm>