From: Misha Bergal (mbergal_at_[hidden])
Date: 2003-07-21 23:27:07
"Beman Dawes" <bdawes_at_[hidden]> wrote in message
> At 05:13 PM 7/20/2003, Misha Bergal wrote:
> >Something seems to be wrong to me tough. The programming languages
> >(environments) introduced lately do not implement fixed-point only
> Fixed-point is used in applications driven by external requirements, not
> what is or isn't available in programming languages.
I don't think people who did Java or C# are ignorant of requirements of
financial applications. They must have had the reasons for doing floating
point instead of fixed point only.
> That's possible, but my guess is that it is going to be a long time before
> floating-point becomes acceptable in the broad world of business,
> and government.
Do you mean that it is unacceptable because of the difference between 1) and
1) Fixed point (2 digits after decimal point) :
1.00 + 1.00 * 0.06 * 300.00 = 1.00
2) One of the implementations using floating point:
1.00 + 1.00 * 0.06 * 300.00 = 19.000000
Well, at least 2) explicitly shows that the necessary rounding did not
occur, in case of 1) it is not so explicit, so I would not be sure that 1.00
is the intended result.
> Try it on your tax return and see what kind of a response
> you get:-?
When calculating my tax return I use the same arithmetic my calculator uses.
I believe it uses floating point.
> Uh... In the applications I have in mind it is floating-point arithmetic
> that has a bad reputation for producing technically correct answers that
> are dead-wrong in terms of the application's needs.
Do you have any references regarding bad reputation of floating point
arithmetic that I can look up?
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