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Decimal Forever
Maybe ;-))


Actually, this is more monkey business than real business

but heck, ya just gotta have a little fun !!

A fun series of e-mails :-))

DECIMAL ARITHMETIC - 5/5/2007
Of course, I'm opinionated - 5/6/2007
You are both wrong - 5/6/2007
Three toed Sloth - 5/7/2007
discussion as silly - 5/7/2007
how about base 60060? - 5/17/2007

From Mike Cheponis - to 1401_team - 5/5/2007



You guys may enjoy this (recently-updated) note on IBM's website
    about DECIMAL ARITHMETIC

Turns out, it's making a big comeback (indeed,
    if it can ever be said that it left!

It's fascinating to see how a large number of problems
    don't work quite so well in Binary as they do in Decimal.

Perhaps the 1401 had it figured out long ago?


http://www2.hursley.ibm.com/decimal/decifaq1.html  for the General FAQ page and

http://www2.hursley.ibm.com/decimal/decifaq.html   for the rest of the sections.


-Mike
Mike@1401.Org

which I forwarded to some friends outside of the 1401 group, asking for opinions
and the following came back

From LaFarr Stuart - 5/6/2007


HI: Of course, I'm opinionated.

This is more noise from  Mike Cowlishaw who thinks the world just has to be decimal.

I am among the few who feel that from a pure "simple arithmetic" point of view
    God messed up when he did not give us 6 fingers on each hand.
Then we would have been using base 12 which DOES have advantages.
    Otherwise, except for tradition, binary is better than base 10.

Mike is British,
   and it is funny he is not proposing making a computer based on Roman Numerals.

LaFarr

and from Bob Smith - 5/6/2007


All right guys,

You are both wrong.

God (if he/she/it exists) should have removed one finger from each hand,
   giving us base 8 (or base 4).

In any case, it seems that this guys argument is that computers must change,
   and not the various stupid rules in the decimal world.

  I hate backward compatibility.

Bob

From LaFarr Stuart - 5/7/2007


Yea, Bob: I agree about backward compatibility.

God/nature, created the "Three toed Sloth".
   but unfortunately computer designers seem to have ignored him.
I guess we have missed our only chance for using base 12.

Cheers, LaFarr

PS. Bob may point out God (??) should have removed one toe from the Sloth?
Two seems to work quite well for such things as pliers, and tongs. Then we
would have had divine support for binary.

From Tim Coslet - 5/7/2007


I see the entire discussion as silly.

Numeric representations are just tools that we use to stand-in for the actual numbers.

Picking the wrong numeric representation for a problem is like picking a hammer
    instead of a screwdriver when you want to put in screws...
    you will have difficulty and things can break.

There are many issues in numeric representations far beyond base
    and fixed vs. floating point.

For example if the problem requires EXACT representation of rational numbers,
   floating point is useless (regardless of base used to represent it).
You must use rational number representation!

I don't know of any computers designed for rational numbers,
   although I do know that the Ada programming language uses rational number representation
   at compile time for what it calls "Named Numbers".
Writing a numeric function library for rational number representation is not difficult.

In other words study the requirements of the problem to be solved
    and then pick the right tools for the problem.
    Numeric representation is one of those tools.

--
         R. Tim Coslet
         rtcoslet@rockwellcollins.com
         (408)-532-4505
         Rockwell Collins Display Systems

From LaFarr Stuart - 5/7/2007


...

When Mike Cowlishaw was proposing a mutilated 16-bit format for decimal
floating point, I suggested floating point base 60060 which is fairly close
to 65,536 and hence would make fairly efficient use of a 16-bit word. The
advantage is: 60060=12*5*7*11*13 (the *'s  mean multiplication) so almost
all fractions with reasonably small denominators, including 10,  could be
represented without truncation errors.

At the time Mike Cowlishaw was obsessed in trying to get IBM to implement
HIS form of decimal floating point in hardware, and didn't want to hear of
anything else. Apparently that effort failed, and he went to IEEE, who in my
opinion will adopt almost anything if it adds enough confusion to that which
should be simple. Example: RS-232 with 25 wires, and two opposite polarity
voltages, when the Teletype Corp. and DEC were doing very well with a 20ma
current loop that had much greater distance capabilities; and everybody
understood it.

Quite frankly, I think computers should stick with plain old floating
binary, and agree with Van Snyder
when he said:
"I suspect the financial applications supposed to be of decimal floating
point arithmetic really ought to be using decimal fixed point
arithmetic"

Cheers, LaFarr


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