RE: Strange result with exponents...

["jt" <jt@xxxxxx>]

Meant to get back to this-un.  Points 1 and 3 are Very well-taken.  My
problem is with point #2:

"Apparently" (to me obviously), the IEEE spec is a "joke" because it's so
out-dated.  And fixed-in-stone standards that don't change with modern
computing end up working AGAINST the computer industry.  Plus, I doubt if a
lot of these kinds-a Standards Bodies even HAD any awareness of the 400
platform to begin with.

| -----Original Message-----
| [mailto:rpg400-l-bounces@xxxxxxxxxxxx]On Behalf Of Hans Boldt
| Sent: Wednesday, February 25, 2004 2:06 PM
| Subject: Re: Strange result with exponents...

| jt wrote:
| > Cheers, Hans...  I couldn't figure out why anyone would WANT to use FP,
| > until you mentioned speed.
| >
| > But I can't possibly disagree More with this statement: "My
| point is just
| > that float format was primarily intended for scientific
| calculations, and an
| > understanding of the concept of precision is important."  It's
| important to
| > You, because you write Turing machines (compilers).
| >
| > And FP (afaik) IS covered in even 2-year programs and so yes, I agree,
| > programmers Should be familiar.  HOWEVER, you have almost no
| understanding
| > of what it is to do biz programming, as you've mentioned
| before.  And if you
| > think biz programmers Should be as familiar as you are with FP,
| then you are
| > mistaken.  When I do arithmetic I want a correct result, not an
| estimate via
| > FP.  Because the arithmetic is only a small SUBSET of the issues I hafta
| > deal with in writing a biz app.
| >
| > I should add, in my experience anyway...  But I'd be surprised
| if there were
| > a whole LOTta people who disagree with this aspect of the problem.
| >
|
| A couple of points:
|
| 1) With respect to business programming, when you do arithmetic on
| monetary values, you want to, no, you NEED to follow the rules and
| regulations governing monetary computations in your jurisdiction. That
| may or may not require "exact" results. For example, as I understand it,
| the EU requires Euro computations to be exact to the whole Euro cent,
| with a certain style of rounding. That is, no fractional cents. Other
| jurisdictions may have different rules. And in cases where the
| jurisdiction does not lay down precise rules, companies may have
| specific accounting policies you have to follow.
|
| My point here is that "correct result" is often largely a matter of
| accounting policy, and it's the job of the application programmer to
| match the capabilities of the chosen tool with the rules. As you've
| said, compiler writers are not generally well versed in accounting
| practice. ;-)
|
| 2) As I've said before, IEEE float will not give you an exact result
| anyways, so of course it should be avoided for monetary calculations.
|
| 3) "Infinite precision" integer operations are certainly available in
| some languages, like Python. But you might not like the performance of
| such interpreted languages compared to compiled languages like RPG. ;-)
|
| Cheers! Hans