HP Calculator Applications in the Workplace

[SEasterling]

This is my first post on the "new" forum since I was absent from the old forum for several years. I followed it closely even though I didn't post that frequently. My first HP was the 28S in 1989, and I quickly filled nearly all the memory with programs and used it extensively throughout college as it replaced my Casio FX-7000g (and other Casio scientific). I loved programming it and using RPL. I've kept my 28S in mint condition with all available manuals and books for it. About a decade ago, I began my HP collection and amassed about thirty different models in excellet to new condition and their storage case upgrades, books and battery packs, from the 35 to the 49G+. (I even bought and framed the big HP Calculator poster in my man cave!) At one time, I even carried my 97 to work each day and used it at my workstation, as well as many of the older LED models. I have since thinned the herd to keep only my favorite models, and the ones I have primarily continued to add to the "collection" are the graphing models. Some notables I retain are new-old-stock 32SII and 48GX with most cards available and nearly all books, etc. in new condition so as to preserve the pinnacle of calculator products from HP. Notables that I let go that I just didn't like as much were mint (NOS) condition HP41CV & CX, 27S, and 42S, as well as a mint 55. (I never could get used to the 41-series display!) I daily use Pioneers and Voyagers for profession and home use. To me, RPN is not just a method, but rather how a person ought to think and approach math, and should be the natural process for solving most problems. (I'll never understand why others insist on algebraic mode.)

Academically, I had many uses for the calculators, but professionally, every time I find the need to use my HP calc beyond the basic use as a scientific calculator, I always end up using the PC for many reasons. I am not a coder or computer engineer, math or science teacher, nor do I write programs out of fun (used to out of necessity), but rather a clinical medical physicist that simply appreciates a quality-made RPN (yeah, made the switch from RPL to RPN) calculator for scientific calculations. So I'm wondering what some of you are using your HP for in a non-academic environment that goes beyond basic scientific calculations (besides civil engineering). This would also give me a good idea of how the calculator has survived over time.

As a side note, I recall in college we were encouraged to use Mathematica to solve systems of equations in my PDE class and calculators were not even up to the task for that. (Can the Prime challenge Mathematica now for the academic crowd?)

Thanks for your patience reading this lengthy introduction post, and all comments are appreciated. And for those of you that work earnestly improving late model HPs, writing programs, fixing the older models, and developing the WP34S,... thank you!!

[Don Shepherd]

(07-12-2014 02:42 PM)SEasterling Wrote:  I have since thinned the herd to keep only my favorite models

Welcome back! Like you, I "thinned my herd" about a year ago, keeping only my 65, a couple of 12c's, a 32sii, and a few 17b/17bii's for solver programming. Oh, and a Victor MEC/2 from 1972.

I'm a middle school math teacher and each year I challenge my students to beat me at "the 50 game." This is a game for 2 players. Players take turns choosing a number from 1 to 6 and keeping a running grand total, and the one who is able to hit exactly 50 is the winner. After they play it a few times, most of them figure out the winning strategy by working backwards: if you get to 43, you will win, and if you get to 36, you can get to 43, and so on. The kids take great pleasure in beating me when they know the strategy. I have programmed my 17b (and other HP calcs) to play this game, and they try to beat it (they go first and if they know the strategy, they will win, but if they goof the 17b will win every time). Kids are lazy a lot of the time, but if you challenge them they frequently rise to the occasion.

My students don't use calculators to actually do math; that's what their brains are for.

[CosmicTruth]

I am a surveyor :-D ....enough said?

[Thomas Klemm]

(07-12-2014 04:59 PM)Don Shepherd Wrote:  I'm a middle school math teacher and each year I challenge my students to beat me at "the 50 game." This is a game for 2 players. Players take turns choosing a number from 1 to 6 and keeping a running grand total, and the one who is able to hit exactly 50 is the winner.

Do you also play it with multiple heaps? I've just written a program for the HP-42S that lets you play the game with 4 heaps: 1 - 3 - 5 - 7
But it's boring as you always lose.

It might be difficult to do that with the solver of the HP-17B as the XOR function is missing. But I'm sure there's a way to circumvent that hindrance.

Kind regards
Thomas

[Don Shepherd]

(07-12-2014 08:48 PM)Thomas Klemm Wrote:  

(07-12-2014 04:59 PM)Don Shepherd Wrote:  I'm a middle school math teacher and each year I challenge my students to beat me at "the 50 game." This is a game for 2 players. Players take turns choosing a number from 1 to 6 and keeping a running grand total, and the one who is able to hit exactly 50 is the winner.

Do you also play it with multiple heaps? I've just written a program for the HP-42S that lets you play the game with 4 heaps: 1 - 3 - 5 - 7
But it's boring as you always lose.

It might be difficult to do that with the solver of the HP-17B as the XOR function is missing. But I'm sure there's a way to circumvent that hindrance.

Kind regards
Thomas

Thanks Thomas. Actually, XOR is included in the 17b solver, along with AND, OR, and NOT.

I haven't considered multiple heaps in my implementation. When you run it, if you win it beeps at you (courtesy \(\div\)0), and if you lose it returns 3507 (I got that from some old HP calculator program, I forget which one at the moment).

[Thomas Klemm]

(07-12-2014 09:17 PM)Don Shepherd Wrote:  Actually, XOR is included in the 17b solver, along with AND, OR, and NOT.

I'm afraid that won't work as this is logical XOR but we need binary XOR. One is the combination of Boolean values and the other operates on the bits of integers.
I get an error message INVALID EQUATION for the equation: A XOR B.

Quote:I haven't considered multiple heaps in my implementation. When you run it, if you win it beeps at you (courtesy \(\div\)0), and if you lose it returns 3507 (I got that from some old HP calculator program, I forget which one at the moment).

.uʍop ǝpısdn ɹoʇɐ1nɔ1ɐɔ ǝɥʇ uɹnʇ oʇ ǝʌɐɥ noʎ uǝɥʇ ʇnq .ʎuunɟ s,ʇɐɥʇ

Cheers
Thomas

[Don Shepherd]

Quote:.uʍop ǝpısdn ɹoʇɐ1nɔ1ɐɔ ǝɥʇ uɹnʇ oʇ ǝʌɐɥ noʎ uǝɥʇ ʇnq .ʎuunɟ s,ʇɐɥʇ

How in the world did you do that?

[Thomas Klemm]

(07-12-2014 10:24 PM)Don Shepherd Wrote:  How in the world did you do that?

Using Unicode.

[walter b]

(: .buıɹɐɥs ɹoɟ sʞuɐɥʇ .ɟɟnʇs ʇɐǝɹb

[Thomas Klemm]

(07-12-2014 08:48 PM)Thomas Klemm Wrote:  It might be difficult to do that with the solver of the HP-17B as the XOR function is missing. But I'm sure there's a way to circumvent that hindrance.

That's what I came up with:

XOR:X=
IF(A=B:0:
IF(A+B=7:7:
IF(MOD(A-B:8)=4:4:
IF(MOD(A+B:8)=3:3:
IF(MOD(A:4)=0 OR MOD(B:4)=0:MOD(A+B):8:
IF(A=7 OR B=7:ABS(A-B):
IF(A=3:MOD(A-B:8):MOD(B-A:8)
)))))))

This works only for numbers in the range 0-7 but that's all we need.

Cheers
Thomas

[Don Shepherd]

(07-13-2014 08:05 AM)Thomas Klemm Wrote:  

(07-12-2014 08:48 PM)Thomas Klemm Wrote:  It might be difficult to do that with the solver of the HP-17B as the XOR function is missing. But I'm sure there's a way to circumvent that hindrance.

That's what I came up with:

XOR:X=
IF(A=B:0:
IF(A+B=7:7:
IF(MOD(A-B:8)=4:4:
IF(MOD(A+B:8)=3:3:
IF(MOD(A:4)=0 OR MOD(B:4)=0:MOD(A+B):8:
IF(A=7 OR B=7:ABS(A-B):
IF(A=3:MOD(A-B:8):MOD(B-A:8)
)))))))

This works only for numbers in the range 0-7 but that's all we need.

Cheers
Thomas

OK, how do you run it?

[Gerald H]

(07-12-2014 10:24 PM)Don Shepherd Wrote:  

Quote:.uʍop ǝpısdn ɹoʇɐ1nɔ1ɐɔ ǝɥʇ uɹnʇ oʇ ǝʌɐɥ noʎ uǝɥʇ ʇnq .ʎuunɟ s,ʇɐɥʇ

How in the world did you do that?

What a wealth of knowledge lies hidden here! Thank you, & thanks for the link.

[Thomas Klemm]

(07-13-2014 12:26 PM)Don Shepherd Wrote:  OK, how do you run it?

Just enter A and B. Then X = A XOR B.

Example:
A = 5
B = 6
X = 3

Am I missing something?

It's probably not worth to follow that path. We'd need that expression several times. It's much easier to semi-translate the numbers to binary, calculate XOR on the individual bits and recreate the result from these:

Example:
A = 5 = 4 + 0 + 1
B = 6 = 4 + 2 + 0
A XOR B = (4 + 4) MOD 8 + (0 + 2) MOD 4 + (1 + 0) MOD 2
        = 0 + 2 + 1

Cheers
Thomas

[Don Shepherd]

(07-13-2014 03:38 PM)Thomas Klemm Wrote:  Am I missing something?

I was expecting something that actually plays the game. In other words, the user enters a number, the calculator responds, and depending upon who hits 50, either the user or calculator wins. That's what my 17b equation does, and that's what I thought you were doing. I don't understand how your program relates to that objective. Maybe it doesn't and that's ok too.

Don

[Thomas Klemm]

(07-13-2014 04:19 PM)Don Shepherd Wrote:  I was expecting something that actually plays the game.

Still not an interesting game: (HP-17B) NIM. But it lets you use the calculator when you want to play the game with somebody else.

In my experience the best way to play this game with someone that doesn't know the strategy is to start first, remove one object from any heap until you can reach a winning situation. Play it like that a few times and then ask politely: or do you want to start? From now on it's guaranteed that you can always win.

Though the calculation is more complicated than in your game you can still do it in your head. Your students could see how the binary representation of numbers could be useful.

Please post the equation for your game as well!

Cheers
Thomasd

[Thomas Klemm]

(07-12-2014 02:42 PM)SEasterling Wrote:  Notables that I let go that I just didn't like as much were mint (NOS) condition HP41CV & CX, 27S, and 42S, as well as a mint 55.
(...)
And for those of you that work earnestly improving late model HPs, writing programs, fixing the older models, and developing the WP34S,... thank you!!

Apologies for my digressions in your thread. Now I'm a little sad since you can't even use my most recent contributions. Welcome back to the new forum.

Best regards
Thomas

[Don Shepherd]

(07-13-2014 08:54 PM)Thomas Klemm Wrote:  

(07-13-2014 04:19 PM)Don Shepherd Wrote:  I was expecting something that actually plays the game.

Still not an interesting game: (HP-17B) NIM. But it lets you use the calculator when you want to play the game with somebody else.

In my experience the best way to play this game with someone that doesn't know the strategy is to start first, remove one object from any heap until you can reach a winning situation. Play it like that a few times and then ask politely: or do you want to start? From now on it's guaranteed that you can always win.

Though the calculation is more complicated than in your game you can still do it in your head. Your students could see how the binary representation of numbers could be useful.

Please post the equation for your game as well!

Cheers
Thomasd

OK, I posted the game here. If my students figure out the winning strategy without my help (and many do), then they have discovered the fine art of THINKING and I'm happy.

[Egan Ford]

(07-12-2014 02:42 PM)SEasterling Wrote:  every time I find the need to use my HP calc beyond the basic use as a scientific calculator, I always end up using the PC for many reasons. ... So I'm wondering what some of you are using your HP for in a non-academic environment that goes beyond basic scientific calculations (besides civil engineering).

Little to none. I've written a few programs and solver setups in the interest of just using my calculators. However, it was just a case of a solution looking for a problem. Day to day I use programs that I have written (data sets too large for a calculator) or Excel. And even though the Mac has an RPN calculator built-in, I use a command line RPN calculator for quick math (its quicker than grabbing one of the four calculators off my desk, and I can cut/paste inputs/outputs).

Personally, I use i41CX as my primary calculator since I have my iPhone with me all the time. I also use the 12C for TVM (very convenient), and lastly I still use my 16C for assembly programming.

(07-12-2014 02:42 PM)SEasterling Wrote:  As a side note, I recall in college we were encouraged to use Mathematica to solve systems of equations in my PDE class and calculators were not even up to the task for that. (Can the Prime challenge Mathematica now for the academic crowd?)

No.

[DavidM]

I started college in the late 70s with thoughts of getting an electrical engineering degree, and got my first hp (33C) to help me on the journey. I think it was the second semester of my first year when I took an elective computer science class that my plans started to change, and I ultimately switched to that program instead.

I've always managed to use a variety of calculator-based programs for work over the years, mostly small utility routines that had something specific to do with the place I was working at the time. Truthfully, though, the most I've ever used my calculator in a working capacity was a few years ago when I was doing some product photography for an international "natural products" firm. The shots I did were mostly for catalogs/brochures and a few point-of-sale applications. Consistency and color accuracy are very, very important for those types of shots.

So how did a calculator come into play? I used a handful of very specific routines I created that helped in two areas: calculating lighting adjustments, and determining specific eV and gamma adjustments while processing the digital shots. At the heart of several of the routines was a series of polynomials that matched to my specific camera/software combination, and it was actually easier for me to punch in a couple figures and press a menu key on the calc than to switch to another PC application while shooting or editing.

Working with the numbers was usually far simpler than translating the creative and marketing groups' instructions into a final picture.

[Thomas Klemm]

(07-14-2014 03:21 AM)Egan Ford Wrote:  I use a command line RPN calculator for quick math

What do you use? Is it "dc"?

Cheers
Thomas