To the moon on a pocket calculator

"Henry Spencer" wrote in message
...
(Catching up after vacation...)

In article ,
OM om@our_blessed_lady_mary_of_the_holy_NASA_researc h_facility.org
wrote:
Thanks, on behalf of everyone. (And I should add that my role in MOST was
modest, and I'm not involved in the commissioning work, so most of the
credit properly goes to others, at Dynacon and SFL.)

Now, for the big question: how'd the Zoology department get involved
with a project like this anyway? :-)

Despite my historical association with the Zoology department, I've been
freelance for a decade now, so I'm afraid there's no connection,
disappointing though that may be. :-)
--
MOST launched 1015 EDT 30 June, separated 1046, | Henry Spencer
first ground-station pass 1651, all nominal! |


Hah, my BS is in Zoology (Protozoology) - but the minor in Physics/Chemistry
(and early WATFOR / WATFIV FORTRAN & BASIC programming)
was just as much fun ! ...
happens when you make college choices in 1973 and just watch Cernan say
good-bye.

Congrats Henry, and as a member of AMSAT-NA, glad we could help in an
advisory capacity for the MOST project.

GB

On Sat, 23 Aug 2003 20:23:08 GMT, (Henry Spencer)
wrote:
...RPN was one of those calculating methods that had absolutely no
reason to come into being.

Well, it simplifies it for the calculator, since I think they actually
do it that way. But personally I think that the calculator should be
doing that work, not me.

G.Beat wrote:

"OM" om@our_blessed_lady_mary_of_the_holy_NASA_researc h_facility.org wrote
in message ...

On Sat, 23 Aug 2003 20:23:08 GMT, (Henry Spencer)
wrote:


In article ,
OM om@our_blessed_lady_mary_of_the_holy_NASA_researc h_facility.org

wrote:

...RPN was one of those calculating methods that had absolutely no
reason to come into being.

So, when you add two numbers by hand, do you write down one number, do

the

addition, and then write down the other number? :-) Or do you write down
both numbers and then do the addition?

[snip]
- to buy one of Radio Shack's first
calculators, which set me back $79 USD circa late 1975. Ran off
9-volt, nice red LED 9-digit display, and had single-result memory as
well.

[snip]

OM


What? No Bowman 4 function (my 1973 purchase)....

I purchased one of those too, when I became a sophomore in college. But
I saved my money, and subsidized by my generous parents, I finally got
to purchase an HP-35. For me, that was more important than owning a car.

Prior to that, I had relied on my trusty Pickett slide rule. I had a
deluxe model with all the different scales, even hyperbolics.





Odd when we thought about it, Apollo moon landings end ...
and the fun tools and toys start appearing (in school we thought this was
great)

gb



--
Steven D. Litvintchouk
Email:

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Jan Philips wrote:

On Sat, 23 Aug 2003 20:23:08 GMT, (Henry Spencer)
wrote:

...RPN was one of those calculating methods that had absolutely no
reason to come into being.


Well, it simplifies it for the calculator, since I think they actually
do it that way. But personally I think that the calculator should be
doing that work, not me.

Sure.

But the first pocket calculators just didn't have enough memory to be
able to parse an algebraic expression with operator precedence and
nested parentheses. Prior to RPN, the affordable pocket calculators
just did simple chained calculations left-to-right, without operator
precedence.

RPN was a compromise in that you finally had a large enough stack to be
able to do the nested mathematical calculations you wanted to do--if you
arranged the calculations properly.

Calculators today have so much memory that they can easily parse nested
algebraic expressions with operator precedence and deeply nested
parentheses.


--
Steven D. Litvintchouk
Email:

Remove the NOSPAM before replying to me.

On Sun, 24 Aug 2003 18:18:34 GMT, "Steven D. Litvintchouk"
wrote:

But the first pocket calculators just didn't have enough memory to be
able to parse an algebraic expression with operator precedence and
nested parentheses. Prior to RPN, the affordable pocket calculators
just did simple chained calculations left-to-right, without operator
precedence.

I still have the very first hand-held calculator I ever saw - a TI
SR-10 I got in 1973, and it has operator precedence.

"Jan Philips" wrote in message
...
On Sun, 24 Aug 2003 18:18:34 GMT, "Steven D. Litvintchouk"
wrote:

But the first pocket calculators just didn't have enough memory to be
able to parse an algebraic expression with operator precedence and
nested parentheses. Prior to RPN, the affordable pocket calculators
just did simple chained calculations left-to-right, without operator
precedence.

I still have the very first hand-held calculator I ever saw - a TI
SR-10 I got in 1973, and it has operator precedence.

Jan -

You are correct Slide Rule (SR) 10 , I will have to see if I still have the
old SR-11
in storage (or if my brother still has it)

gb

Jan Philips wrote:

On Sun, 24 Aug 2003 18:18:34 GMT, "Steven D. Litvintchouk"
wrote:


But the first pocket calculators just didn't have enough memory to be
able to parse an algebraic expression with operator precedence and
nested parentheses. Prior to RPN, the affordable pocket calculators
just did simple chained calculations left-to-right, without operator
precedence.


I still have the very first hand-held calculator I ever saw - a TI
SR-10 I got in 1973, and it has operator precedence.

There were earlier and more primitive calculators.

One of the first "hand-held," but bulky, 4-function calculators was
produced by Canon in 1970. I'm sure it lacked operator precedence--it
had only "+=" and "-=" keys, instead of a separate "=" key. One year
later, the first true pocket calculator was produced by Bowmar, with
similar keypad.

HP's first scientific RPN-based pocket calculator, the HP-35, was first
sold in 1972.


--
Steven D. Litvintchouk
Email:

Remove the NOSPAM before replying to me.

marcus hall wrote:
In article ,
G.Beat wrote:

What? No Bowman 4 function (my 1973 purchase) or TI-10 (or TI-11 with Pi
! )?
Started sophomore year (HS) with slide rule .... and used it only 1/2 time
senior year.


Wasn't it a "Bowmar brain"?? I seem to recall that in advertisements...

Yes, the Bowmar Brain was one of the first pocket calculators,
co-produced with Casio (IIRC) around 1970. Perhaps the gentleman
purchased a newer model in 1973.


--
Steven D. Litvintchouk
Email:

Remove the NOSPAM before replying to me.