just a kick comment.
We use Fraction, no ScaledDecimal, no Float. We made some changes to
fraction to work faster. We didn't see big performance diferences with
ScaledDecimal.
We use measures to represent all type of quantities of some financial
instrument. For example:
100 dollars
100 IBM
100 bond (any bond)
etc.

Bye,
Hernan.

On Nov 22, 2007 5:50 PM, Sebastian Sastre <ssastre at seaswork.com> wrote:

> > -----Mensaje original-----
> > De: squeak-dev-bounces at lists.squeakfoundation.org
> > [mailto:squeak-dev-bounces at lists.squeakfoundation.org] En
> > nombre de Tom Phoenix
> > Enviado el: Jueves, 22 de Noviembre de 2007 17:59
> > Para: The general-purpose Squeak developers list
> > Asunto: Re: 5.3 printShowingDecimalPlaces: 2 displays '5.29'
> > insteadof'5.30'
> >
> > On 11/22/07, Sebastian Sastre <ssastre at seaswork.com> wrote:
> >
> > > Let's supose the user enters in some
> > > input widget with keyboard the '5.30' value. That will end
> > as a Float
> > > at some point.
> >
> > Why will it?
> >
> > We're talking about monetary units. If you start with a
> > string like '5.30', meaning 530 monetary units, it won't "end
> > as a Float" all by itself. If somebody somewhere wrote code
> > that converted it to floating point, that's a bug.
> >
> Even if you don't use computers to achieve that, when you make monetary
> values to pass trhough functions they *are* mathematically represented as
> float numeric values. At some point we simplify presentations (like the
> balance books you mention) of the values.
> I certainly agree with you about units. In fact there are equivalence
> units.
> 100 cents are 1 dollar, 4 quarters also are equal to 1 dollar and 100
> cents.
>
> Aconcagua framework seems to deal quite well with that trough it's
> Measures
> (and amount and a unit). For monetary measures I think I'll store scaled
> decimal amounts to gain the accuracy you propose.
>
> > Don't be misled by what looks like a decimal point. If you're
> > working with money, you don't want floating point, no matter
> > what your programming language. Floating point will lose tiny
> > bits due to roundoff; but money numbers are almost always
> > integral numbers of cents, and you don't want to lose any of
> > them. Floating point may be needed to perform some
> > calculations along the way, but you'll use integers to get
> > the books to balance.
> >
> I agree. With measures I think I'll be able to achieve that, by using
> scaled
> decimanls in the amounts of the measures, and the rounding will be
> performed
> only in presentation time by the converter of the widget and not in the
> internal process, formulas or calculation of the value.
>
> Cheers!
>
> Sebastian
>
>
> > ObSqueak: 5.30 asFraction
> >
> > Cheers!
> >
> > --Tom Phoenix
> >
>
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.squeakfoundation.org/pipermail/squeak-dev/attachments/20071123/16ae146f/attachment.htm