Re: BUG #5150: math bug

David Fetter <david@fetter.org>

From: David Fetter <david@fetter.org>
To: John R Pierce <pierce@hogranch.com>
Cc: PostgreSQL Bugs <pgsql-bugs@postgresql.org>
Date: 2009-10-31T05:45:21Z
Lists: pgsql-bugs
On Fri, Oct 30, 2009 at 08:51:57PM -0700, John R Pierce wrote:
> Tom Lane wrote:
>> There is special-purpose software out there that can compute
>> exactly with rational numbers, but you aren't likely to find it
>> embedded in any general-purpose tools like databases --- the
>> use-case just isn't wide enough.  One reason why not is that it'll
>> still fall down on irrational numbers.
>>   
>
>
> <nit>
>
> 1/3 is a rational number.  however,  it is a repeating fraction when
> expressed in decimal.
>
> </nit>

<nit level="2">
The set of algebraic numbers, of which rational numbers are a proper
subset, is countable and hence has Lebesgue measure zero on the real
line.
</nit> ;)

Cheers,
David.
-- 
David Fetter <david@fetter.org> http://fetter.org/
Phone: +1 415 235 3778  AIM: dfetter666  Yahoo!: dfetter
Skype: davidfetter      XMPP: david.fetter@gmail.com
iCal: webcal://www.tripit.com/feed/ical/people/david74/tripit.ics

Remember to vote!
Consider donating to Postgres: http://www.postgresql.org/about/donate