Proposal for modifying gnucash to use exact quantities

[Buddha Buck]

At 11:25 AM 8/2/00 -0400, Jason Rennie wrote:

>bmbuck@14850.com said:
> > I view "$/8 USD" and "$/100 USD" to be -similar- commodities.  You
> > can't  add or subtract them, but comparison should be possible.
>
>Is it true that you would *never* want to add/subtract such
>commodities?  I can't think of any cases where you would want to, but
>should we building this assumption into our underlying data
>representation?

Yes.

What is the result of $3/8 USD - $0.30 USD?  I can think of several 
reasonable, but wrong (IMHO) answers:

   $0/8    (round down)
   $1/8    (round up)
   $0.07   (round down)
   $0.08   (round up)
   $15/200 (take LCD for denominator)
   $60/800 (take product for denominator)
   $0.075  (go to mills)

I don't think any of those make as much sense as saying that subtraction 
just isn't defined between two similar or different commodities.


>Jason D Rennie                      www.ai.mit.edu/~jrennie/
>MIT:  (617) 253-5339                      jrennie@ai.mit.edu
>MITRE: (781) 271-7249                      jrennie@mitre.org