Beginners RPN needed


I strongly feel the need for a beginners RPN calculator for non- professionals and kids. I would like to see something other than algebraic entry taught. I think that extra complexity turns newbies off to math. I would personally gift several to children I know of. I really hate to be limited to algebraic and all the key pushing.


FWIW, I second your request. IIRC, we had threads about this very topic some times in 2007 - and earlier. Also several nice design proposals were posted. However, these threads ended like all the other design threads so far: no one of the community had the power to execute even one of them, incl. HP. These are the experimental facts :(

I leave aside here all the necessary considerations about target markets etc. because others are more professional in this field - and such thoughts will not stop an aficionado from carving his very own calc if all the other tools were available.

Nevertheless, the HP35s shows some guys at HP read this forum sometimes. So hope dies last :)


Why not buy a Novus Mathbox off the unmentionable auction website? It is a very simple RPN calculator. I will list one in the next week or two as I have a couple of them. But first, I have to get around to charging up the digital camera batteries.

Edited: 26 Jan 2008, 8:21 a.m.


That's all it takes.

A new product beginner RPN: not going to happen.

RPN is obsoleted. I doubt HP will ever produce an RPN-only machine ever again. I think the dual version is clever. It keeps compatibility and core market share while also being universally appealing. Of course I use RPN and generally prefer it out of habit. But I find that for programming, I go for the equation approach first.--which is much easier to write and debug than the old RPN line by line equation entry (as in 15c).

If RPN is so easy, why would we need a "beginner's machine" anyway?


Bill, what I am saying is we need a "$10" calculator that you would trust a child with in a class of who knows who.
I submit that RPN would make learning math easier for beginners.
Sure, you can copy formulas from a book, but most books were written in the dark ages and copied from one to another without recognizing that calculators (computers) have changed the nature of math. I started with RPN on the original HP-35 and am ill at ease with formulas in algebraic. I always rewrite them for the calculator and work faster because of it. I hate to see kids strapped into algebraic expresions with the complication of adding parenthesis when learning. If adding algebraic takes away anything from the ease of using an RPN calculator it should be eliminated.
In my opinion it takes away and should be eliminated. In spite of our high tech country, our students perform math badly compared to other countries. We had Vietnamese students who had little English knock the top out of our math classes. There are plenty of cheap algebraic calculators, but no RPN ones which I feel are inherently faster.


Ooops, did the Vietnamese take over RPN?? ;))


Kids should not be using calculators until college in general. This is a massive educational problem here in North America.


Sorry about that, I know of 11 year olds required to have calculators for school. I don't think students gain anything by being bogged down by long division or multiplication or taking square roots or solving quadratic equations. Thats nuts and bolts. What they need is principles and methods. My dad was a whiz at mental math, he could do problems in his head I couldn't do with pencil and paper, but that was ages ago. What's the point now? Who does pencil and paper math now? Sam age 80.


What's the point? Hmmm. Let's see, as a *designer* I can tell you that being able to do arithmetic in the head makes a world of a difference. The ability to work stuff out at the speed of conversation makes for a better design--more productive meetings, faster hashing out of concepts, more exploration of ideas, clarity in checking the validity of computer-generated results...just to name a few.

"Principles and methods" exactly. Understand the principles of numbers and be capable of using/manipulating/computing regardless of the tools at hand. Education in numbers that is reliant on machines is bankrupt. The next set of machines, the next paradigm of computing, will leave you in the dust--just as the abandonment of RPN has left you off balance, so too will reliance on any technology for maths pedagogy.


"Principles and methods" exactly. Understand the principles of numbers and be capable of using/manipulating/computing regardless of the tools at hand. Education in numbers that is reliant on machines is bankrupt.

You are right!
Just an example to illustrate your point. Consider the simple problem:

 1 + 3/2 + 5/4 + 7/8 + ... = ? 
If all you want is the numeric result, then any calculator, even non-programmable ones, will do. On the HP-48, for instance, just evaluate 'SIGMA(n=0,50,(2*n+1)/2^n)'. On the other hand, if you have to prove your result, then no calculator in the world, either RPN or algebraic, will be of help.



Gerson, you have illustrated my point. Where in the real world does such a "problem" arise? It is contrived as a problem. We are teaching things that are classic but unreal. Would not decimal measurents be enough? We can't even switch to metric, "because that's not the way we were taught". We have to teach the young and let the old ones die off. It may be surprising but Great Britain survived the change to metric in large part. One lady referred to the decimal currency as metric. We won't have time for the new if we keep teaching the old. I agree with the prof you quoted that fractions and long division are unreal and should not be taught. Rather we should be teaching them to be able to handle money and shop, and what delayed gratification is. We elders simply don't admit that kids are smarter than we are. My mom couldn't figure out how the plugs on her tape recorder worked, I suggest she ask any 12 year old, she was insultted.. But if you see kids who have grown up with computers they learn it easier and better than their elders.


Designnut, this is a recurring subject in this forum, and it is always interesting to see the different perspectives among us. Yes, I heard of the professor who recommended not teaching fractions and long division. As long as newspapers keep reporting that "only half of the registered voters voted in the last election," we have to keep teaching fractions. They have not vanished in our world today. And as long as do-it-yourselfers have to figure out how many fence posts and feet of fence they will need for their project, we have to keep teaching long division. Everyone does not have a calculator, even if everyone can afford one.

I agree with Bill Platt when he says that we need to teach the fundamental principles of numbers, and let the kids figure out how to solve the problems, with our guided assistance, because knowledge they generate themselves lasts a lifetime, versus knowledge spoken by the teacher lasts 3 nanoseconds.

The public education industry needs to recognize that not all kids will need algebra, but everyone in our society needs to know the "basics" of math: addition, subtraction, multiplication, and yes, division. Basic math principles, like the proper use of grammar, never go out of style.


As for long division: I'm sure you are aware of the Penn professor who stands in the vanguard of yet another "new maths" approach in which long division and indeed even fractions are rendered to the "dustbin" as I think the WSJ put it.

Well, whether it is long division, or short division, or long multiplication or multiplication by parts or any number of other methods, good maths pedagogy encourages development of both deductive and inductive reasoning and very importantly, the understanding of fundamentals with encouragement of a student's ability to develop methods directly from first principles. A reliance on "now follow me class, this is how you compute" is a terribly flawed approach except for showing example. The goal should be to see the students develop the solutions from a point of deeper understanding. Such an understanding comes from some rote or followed worked examples but grows from there with the right awareness on the teacher's part.


I hate to see kids strapped into algebraic expresions with the complication of adding parenthesis when learning.

But the thing is, those parenthesis etc are fundamental to the notation and they must be learned. To be uncomfortable with them is to be uncomfortable with the fundamentals of conventional mathematical notation. If this is enabled by RPN, then I say good riddance.

Really, the calculator is a total distraction from learning maths. It doesn't belong in a maths classroom. I know, everyone uses them now blah blah blah which is more a sign of successful marketing combined with substandard teachers. I had more crappy maths teachers than good ones. You really have to teach yourself if you want to know anything in maths anyway.


I found what is taught in schools and college is really old hat. You don't get to the cutting edge until you are in industry or advancing the state of the art. For me the ability to analyze a problem was required in most cases. Problems never present themselves as pure math. Only one case I can remember required the manipulation of trigonometric identities. Using the HP-41 I was able to use the regression to solve a gas leakage mystery. You don't do that by hand. After the HP-35 came out I saw a friend carryng a huge math tables book. I asked him where he was going, he said retiring it to the archives. We don't use trig tables and interpolation anymore. Just push the buttons. It is really surprisinng the number of books no longer in use for math. I recall the hand labor needed to calculate the radiation resistance of short whips obviated by the calculator. Lets use the best tools at hand. Mans ascendency was by his brain, hand labor could not accomplish where we are today. Sam


All true. But note that what you are talking about are tools--be they books calculators, abacus whatever. The understanding of maths is all internal, and doesn't really change--except to get watered down by spending too much time learning new machine paradigms every 5 years or to that end, old dogs do just fine using RPN (like me, and a lot of senoir engineers out there!).


I am an engineer who is also working on a masters degree (aerospace eng). In my experience, supervisors are often reluctant to advocate rigorous mathematical developments in the place of PC tools we have at hand. This is a slightly special case, as my industry experience is isolated to the time I spent working at a 'fly by the seat of your pants' aircraft R&D shop, where we were developing prototypes, so we were shielded from certain rigor/requirements found in production programs.

On the other hand, I'll reply to your comment on the obscurity of a knowledge of trig-identities:

Only one case I can remember required the manipulation of trigonometric identities.

In a recent course on advanced aerodynamics, we were assigned a very vaguely-stated problem, whose solution took four pages to develop. A classmate was dumbfounded by the problem, and was unable to even develop an approach (despite the fact that he bachelored in aero, while I came from a mechanical background). I, on the other hand, developed an approach, which began with a basic but far-reaching equation (relating to pressure gradients). After four pages, I arrived at a coupled set of differential equations, which I could not simplify due to a 'missing' trigonometric link. I felt confident in the solution method, and due to time constraint chose to stake a claim that the trigonometric details were not significant to demonstrate my understanding of the theory.

My professor chose to award 0.75 to me. Had I had time to refer to my trig identities, I'd have scored 1. This was certainly out of the ordinary (often, difficult problems are graded based on a student's grasp of the central theory, and not supporting "clerical" work).

Yet, I was affected by the outcome, and viewed it as a "re-calling" to my roots. Early on, I'd never have regarded such details as "clerical."


I'm not sure that more trig practice would have helped you recall what you needed, I feel I spent a lot of hours doing busy work with math homework. what you don't practice you lose. I had a physics major friend that was really good at formula manipulation. He took a formula for loss through fog and turned it around to solve for backscatter. Hopefully we all have some expertise. I went to him for answers, he came to me for designs. Sam

Possibly Related Threads...
Thread Author Replies Views Last Post
  [PRIME] RPN: another attempt at returning more than one value to the RPN stack Marcus von Cube, Germany 5 978 11-05-2013, 02:44 AM
Last Post: Marcus von Cube, Germany
  [OT?]Orthography corrector needed. Diego Diaz 8 1,054 06-22-2013, 04:31 PM
Last Post: Andrew Nikitin
  HP-50g How to store many equations - help needed Timo Labrenz 5 856 03-03-2013, 12:22 PM
Last Post: Timo Labrenz
  Disaster: help for a couple of HP97 needed! Jose Gonzalez Divasson 10 1,172 01-21-2013, 04:45 PM
Last Post: aurelio
  HP41 emulator for HP48sx - keyboard overlay needed Doug (NYC) 3 657 12-31-2012, 03:11 PM
Last Post: Allen
  restoring HP29C - help needed Alberto Fenini 9 1,093 11-25-2012, 07:56 AM
Last Post: Alberto Fenini
  Re: WP 34S Beginners Guide David Persinger (US) 1 377 05-31-2012, 04:12 PM
Last Post: Marcus von Cube, Germany
  HP-IL beginners question John Abbott (S. Africa) 4 680 05-28-2012, 05:45 PM
Last Post: Geoff Quickfall
  WP 34S Beginners Guide Ciaran Brady 4 582 05-25-2012, 12:51 PM
Last Post: Brian Walsh
  WP 34S - A Beginners Guide Ciaran Brady 48 3,930 05-24-2012, 04:22 AM
Last Post: Ciaran Brady

Forum Jump: