RPN for Kids.



#56

Hallo!

Some folks did thinking about new HP calculators and they think about High End.

I make my own thoughts and I wonder why nobody thinks about the low end.
How did we learn to use a calculator, with SOLVE or with Matrix or with Statistic?

No, we used + - / x = and some other keys. But did we learn to ENTER first? No our first calculator was Algebraic, and I looked around. What calculator I would give my two Children in School?

There is no simple Calculator with RPN.

That´s what we need. A simple HP 35 or HP 21, for the first steps. But I don’t want to give them an HP 35 A. How long did it work under that terrible conditions?

A simple Calculator based on the very good looking of the 35s with a good keyboard like the 35s and (it is very important for the survival of the calculator in school) a good hardcase like the 35s. But only with capabilities of the 21 or the 31.

What do you think about that that idea.

Greetings Juergen


#57

Definitely very useful. In fact something exactly like a 21 for example would be great except for the display changed to LCD to have longer battery life.


#58

But it should include the RPN option, so that in the future, assuming a calculator manufactured under today's paradigm can survive until the student matures some more, he can explore RPN.

#59

Actually, I think it's a great idea. I've had some similar thoughts (I seem to be on a bandwagon to get HP's back into the educational market, for some sadistic reason ;-) and I would like to see something like that materialize.

It would also satisfy those who have been asking for a basic 4-banger with RPN functionality.

My main concern, however, is acceptance. HP would need to do a GREAT job of not only marketing it and showing it off well, but providing educational materials included with it. Remember, the *parents* are typically the ones buying calculators, and unless THEY understand what the benefit is, they have no motivation to diverge from the norm. Put a great, short example on the back of the packaging and maybe it might survive.

It's a great idea -- just tough to realize.

thanks,
bruce

#60

Hello!

Quote:
What do you think about that that idea.

Honestly, I am one of the heretics that do not believe in the inherent superiority of RPN. Rather, I am a Darvinist who believes in the survival of the fittest, and obviuosly RPN is not amongst those when it comes to education.
Using RPN calculators at school would be a bit like teaching people to drive cars with right-side steering wheels in a country where one drives on the right hand side of the road.
Anyway, it is not going to work simply because teachers do not understand RPN because most of them have ever seen it before.

And it is far more important to understand the mathematical problem then to punch numbers into a little box - the way the numbers are entered is of even less importance.

Gretings, Max

NB: The first calculator I gave our little son is neither RPN nor 'algebraic', but a 'Little Professor' that asks the children for the correct numbers and not the other way round :-)

Edited: 22 Aug 2007, 2:46 p.m.


#61

I tell my son to memorize! Bah, I not buy him calculator until about year ago. He sophomore in high school. He tell me this year he want graphing calculator as all other kids have. I tell him I get him graphing Hungarian calculator. It consist of slide rule, pencil and graph paper. There his graphing calculator. He say he not happy, I say it NOT my job to make him happy. My job to see that he get educated and smart. Laziness bring struggle and I will not allow lazy son. If teacher think he need graphing calculator, then I go talk to teacher, and educate teacher. If teacher insist, then I make teacher buy graphing calculator, and pay for his college education too. He smart boy and I not want him to be lazy. He can do square roots very quickly in head. I don't think any of his friends can do that. Sure, he have calculator now, and I very mad when I told he must have one, but I do not want him to get sucked into lazy culture of do everything easy. Life not easy, so he need to get used to it.

I come to this country with little money, and now I have two homes, cars, boat and airplane. That come from hard work, same hard work I wish him to do so he is proud of himself. When he is proud of himself and can say he is successful, then I know I did my job as his father. If he struggle because of laziness, then I failure as father.

Edited: 22 Aug 2007, 10:10 p.m. after one or more responses were posted


#62

Vincze…

I like your style.

Fred


#63

Thank you my friend. I ashamed to say too many people say I bad father. I guess I should be proud because my son will be a good man and successful.

Edited: 22 Aug 2007, 10:12 p.m.

#64

Hi Vince!

On one side i accept your opinion, some times i do the same with my kids, but on the other side dont force your son to go the same way as yours, (it was a other time and a other place).

Let him stand upon your shoulder and he can reach much higher you ever think.

Greetings Juergen

#65

To me...

It's not about preserving RPN via the classroom because we're convinced it's more efficient. It's not about Darwinian survival of the fittest notation. It's about presenting an opportunity for students to learn an alternate method to something they take for granted.

That said, I doubt RPN should be made a part of general curriculum in high schools (or their equivalent). For many that are math-challenged, anything that gets in the way of an already limited mathematical intuition will serve only as an unnecessary distraction.

On the other hand, as expressed in another post, by all means introduce RPN to students that excel at math. These are the ones that will likely benefit from the choice of notations - and likely pursue careers where that choice will have an impact.

This approach doesn't require schools to adopt RPN calculators en mass in place of ALG models (which we all know will never happen). Instead, the exposure would be limited to advanced, college-prep math courses and more capable instructors.

#66

Max…

Better does not always survive. It is often overwhelmed by the shear weight of mediocrity. Why else would my favorite baseball team be in last place, while their arch rivals are in the hunt for a playoff spot? :-)

When my son took high school calculus a couple of years ago he was the only student with an HP (I let him borrow my HP-48G). All the other kids had TI-89s or some such. The teacher was basically forced to teach a TI-centric curriculum because that is what was available to him. However, the teacher was actually thriled that my son had an HP because the teacher's calculator of choice was a 48GX.

My son is no calculator nerd (he's a computer nerd), but he learned how to use the HP pretty well and could run rings around the kids with the newer, faster TIs for that reason. The key is that he learned how to use the tool (unlike his peers) and he learned it because he liked the way it operated, starting with RPN. Previously he showed no interest in my modest calculator collection, or the fact that I use an HP-42S every day at work. He had a simpler TI calc for Algebra II and Trig and his two older sisters had TI graphing calcs. However, after trying out his sister's calcs he asked to borrow my HP instead and decided to learn how to really use it. He turned down a chance to have a NEW electronic toy AND to be the oddball in his class. Certainly not a normal choice for a teenager.

I realize that this is the exception, not the rule, but there is still a market for the intellegent calculator user for RPN.

Fred


#67

Fred --

You, and your son, are making my point beautifully. You son had a choice. He chose to use RPN. That decision alone doesn't make him a genius or anything, but it shows someone who is truly willing to work a bit harder for something that might even only be personally rewarding. He balanced going with the norm against perhaps really finding out something unique, and that was a great, mature decision.

Bravo! I wish there were more kids like your son in this world.

thanks,
bruce


#68

Bruce…

If there were more kids like him, I would have quite a few more exemptions I could claim on my income tax :-)

Fred

#69

Max,

You may be a Darnist B^) but Crocodilians, tuataras, coelacanths,
and others are still around after 90 million years. So I think RPN will be around (if only in certain environs) for quite awhile.

Ren

dona nobis pacem

#70

Hi, Juergen:

Juergen posted:

"There is no simple Calculator with RPN. That´s what we need."

    It's arguable whether we need it or not, but our children certainly don't.

    I see no reason to handicap them in class just because of their father's private hobby.

Best regards from V.


#71

Wow Valentin, that's pretty harsh. I don't believe learning, or using RPN, is a handicap -- whether it be in school or career. In fact, if I had your attitude, I wouldn't teach anything but Java or C++ in universities because they are the dominant languages. I'd skip needless other programming languages.

A good engineer, a good programmer, a good mathematician or whatever, uses a toolbox of options and choices. The answer to a problem should be the best tool for the job, not some "religious" belief that one way is better than the other, or just because it is all that is taught, it is the only style to be used. To constrain oneself to learning one way of doing something is rather narrow minded.

Algebraic may be the dominant methodology today. And RPN might be a past bygone. But it is, by no means, a handicap. Take a look at those kids in the Texas Math Challenge (thread elsewhere on this page) and how they have grown and expanded their mind by using RPN.

Whether it is my hobby or my father's is irrelevant.

thanks,
bruce

Edited: 22 Aug 2007, 4:11 p.m.


#72

Hi, Bruce:

    Harsh or not, my assessment is an accurate one and I'll give some reasons why I think this is so:

    • Nowadays, next to noone uses RPN calculators in class anymore: not certainly most teachers, not certainly most pupils. For efficiency reasons, the teachers need to standardize and due to a number of important factors, not the least of which is the fact that all mathematical texts use standard algebraic notation, they chose algebraic calcs. This is a fact, and going against it is comparable to driving by the wrong lane, you're going to crash and burn.

    • There's also the fact that, due to market pressure and other factors, the number of RPN models in the market is very small, a negligible minority in the calculator market to say the least. Essentially, only one company still makes them, and there are very few models to choose from, namely the HP-12C, HP33S, and HP35s, if we stick to classic RPN, all of them subject to some serious limitations such as an absolute lack of I/O, for instance. So if you're used to classic RPN or want to introduce it to your children, your options are few and, mostly, relatively expensive compared with the algebraic offer.

      There's also the distinct possibility that the only company making them decides that they're not worth the effort, their sales aren't enough to justify the costs, and so the powers-that-be might as well decide to write them off the market, thus completely terminating their actual, precarious availability for good.

    • It's also a proven fact that RPN tends to generate what could be termed as 'addiction', in the sense that once some people are exposed to it, they'll get hooked to the point where they won't feel comfortable at all having to use any normal, non-RPN calculator, and would be highly inefficient using them, if at all, and would do whatever it takes to avoid using them, as they simply can't cope with algebraic machines anymore, at least not without feeling extremely uncomfortable while doing it.

      If these people were then to be forced to use an algebraic model (because class regulations make it mandatory, for instance) they would automatically be in great disadvantage and severely upset, with both factors potentially capable or seriously damaging their assimilation of the subject matters being taught.

    • Combining all of these factors, you can see that by introducing your children to RPN, you risk they getting hooked on a paradigm which doesn't resemble what they see printed in their books, doesn't coincide with the procedures and keystrokes taught in class, and forces them to either adapt and convert on the fly what's being taught to their RPN ways, or else burden the teacher with the task of dealing with them and their RPN way of doing things, thus generating inconvenience for everyone there: the teacher, the rest of the class, themselves.

      Also, once they're hooked, they'll have to confront the fact that, in the near future, there may be no RPN calculators easily available, and they'll really, really resent having to use an algebraic model, thus suffering a kind of abstinence syndrome for the rest of their lives. I know of *many* people, friends of mine and colleagues alike, that suffer from the RPN bug: they simply *can't* use an algebraic calculator with any decent proficiency, to the point that they'd rather take their NIB collectible HP-15C out from the box and into the dusty construction site if necessary if contemplating the possibility of being forced to use any algebraic calc.

      I see this sheer reliance on an obsolete paradigm which surely faces extinction as a dangerous and unnecessary niche adaptation, which can be no good in the long run for the person aflicted with it.

    • Also, there's the myth of RPN being perceived as "superior" to algebraic systems, offering this or that "advantage", which "absolutely compensates" and overcomes any alleged disadvantages.

      As I've posted in several threads in years past, this is essentially a myth, mostly based in the fact that it was indeed true in the very early times, when calculators had a single-line, numeric-only display, extremely little RAM, and working with an algebraic machine essentially meant that your worked through your expression blind, seeing only one number or result at a time, not seeing the operators, not seeing the whole expression, not being able to ascertain whether you had opened or closed that parenthesis or not, not being able to ascertain just where you were in the process and continually risking getting lost and having to restart it all over again.

      Compared to that, RPN and its 4-level stack was really the much more elegant, superior paradigm, by far, there was no contest at all, anyone could clearly see it. But 35 years have passed by, and while classic RPN hasn't barely changed one iota, algebraic models have experienced authentic quantum leaps. You can now see your whole expressions as you type them, in clear alphanumerics, you can edit them, re-evaluate them, the parentheses are automatically closed for you, ... yet people hooked on RPN still rely on comparisons from the earlier times: "If RPN was so utterly superior then, it surely still is, right ?" Dead wrong ! They simply adamantly refuse to acknowledge the advances in the algebraic camp, and in many cases can't be even bothered to try them or put them to the test on their own.

    • Lastly, one of the usual arguments in favor of teaching RPN to kids (or of using RPN in general) is that it allows you a more intimate understanding of the expression you're evaluating: you can see intermediate results, you can check them on the fly, the fact that you must frequently pre-decide the order of evaluation makes you more aware of it all ...

      In reality, this is akin to making virtue of necessity. It's not that you can do that with RPN, it's that RPN forces you to do things that way: you must see intermediate results, whether you want or need them or not, you must spend time and effort to pre-decide the order of evaluation whether you want it or not, lest you risk losing items out of the top of the stack, ...., which can happen nevertheless if you chose the wrong order. In which case, you'll have to restart from the beginning, as used operators (and probably most of the intermediate results) are not recoverable.

      This is similar to the arguments rised in favor of doing calculations with slide rule when the first electronic calculators arrived: many insisted that doing them with the slide rule required a more thorough understanding of the problem, what with re-scaling being constantly needed, and that forced you to think about your numbers and prevent mistakes or erroneously scaled results.

      Those arguments seemed very solid in theory, but in practice they quickly died away, and I don't think that any parent would insist in their children going to school armed with slides rules because that would "enhance their understanding" of how results are computed and their accuracy. It might sound good, but it would be absolutely handicapping.

    The bottom line is: who cares about the calculations ? About whether intermediate results are seen or not ? About how we do our operations, whether algebraic and parentheses or RPN and stack ? The important thing is that the children understand the problem, understand the algorithms used to solve it, and can correctly write down the necessary expressions that get the results from the initial data.

    How these expressions are evaluated is absolutely irrelevant. It could be by hand, with an abacus, with a slide rule, with an RPN calculator, with an algebraic calculator, or by saying aloud "Computer: evaluate this, please" in a near future. Who cares !?

    The important thing is the understanding of the problem and how to produce the expressions required to correctly solve it, not the mechanics of
    actually evaluating the resulting expressions. And as things are right now, I won't be the one to burden and handicap my children with obsolete *evaluation* paradigms, which are irrelevant to the definition and understanding of the problem, and which surely will be gone in a few years.

    I'd rather have them dedicate their class time to understanding the problem and algorithms, rather than wasting precious time trying to adapt on the fly what is being taught to some obsolete "evaluation" paradigm.

Best regards from V.

Edited: 23 Aug 2007, 7:32 a.m.


#73

Hello!

Didn't I say all this in one sentence yesterday already :-) ?

To quote myself:

Quote:
And it is far more important to understand the mathematical problem then to punch numbers into a little box - the way the numbers are entered is of even less importance.

Back at school and university, in mathematics and physics exams we would get around 4/5 of our points for writng down the correct solution (in terms of formulae etc.) and only about 1/5 for the correct numerical result. And especially at university, the problems to solve were difficult enough so that most students couldn't even produce the correct solution in the time given, so usually the calculators didn't get turnded on at all during the exams.

Greetings, Max

Edited: 23 Aug 2007, 8:03 a.m.


#74

Hi, Maximilian:

Maximilian posted:

    "Didn't I say all this in one sentence yesterday already :-) ?"

      All of it, no; just about 16% or so. But probably the essential 16% ... :-)

    "Back at school and university, in mathematics and physics exams we would get around 4/5 of our points for writng down the correct solution (in terms of formulae
    etc.) and only about 1/5 for the correct numerical result.

      Same here, at my university getting the wrong numerical result would detract nothing from your mark as long as the exposition was sound and the relevant resulting expressions to be evaluated were correctly arrived at.

Best regards from V.

#75

Quote:

    All of it, no; just about 16% or so. But probably the essential 16% ... :-)


I think it more like 16.213% ;)

#76

Damn, you're right !

This damned algebraic thing, I closed the wrong parenthesis again @|~#@~!!

(Best regards from V.)


#77

LOL :-D

#78

Valentin,

A counter argument for teaching RPN (at least in comp sci courses)
it shows how Post Fix Notation is used with stacks.
Understanding that fundamental can lead to more efficient programming.

Ren

dona nobis pacem

#79

Quote:
Hi, Bruce:

Harsh or not, my assessment is an accurate one [...]


Your opinion it might be, but I disagree that your assessment is accurate.

Quote:
For efficiency reasons, the teachers need to standardize and due to a number of important factors, not the least of which is the fact that all mathematical texts use standard algebraic notation, they chose algebraic calcs. This is a fact, and going against it is comparable to driving by the wrong lane, you're going to crash and burn.

Instructors (and schools) clearly need, and benefit from, standardization. There is a huge value in that, both in instruction and in merely saving money. However, textbooks are not as "standard" as you think.

In fact, the recent trend in higher-ed math/stat/finance textbooks is to offer "how do I do this with my calc". They list a couple of different ways of accomplishing examples using 2-3 calculators as the model of choice. There's no reason why HP couldn't aggressively and actively court the textbook publishers to include HP calcs using RPN as an option. Mostly, the publishers and authors just want someone to write that for them. They resist putting HP calc explanations in there because (1) up until recently, HP shunned the educational market, publishing included, (2) they don't have the time or incentive to write each example themselves, and (3) they don't know the technique of RPN. BUT! If you offer to write it for them, they're all for it. I contacted an author of a statistics text for higher-ed last year and discussed it with him, and he was quite open to me submitting an HP-specific approach to the examples. The publisher appeared to be open as well, although I never followed up on it (um, I got busy elsewhere, unfortunately).

Going against the flow of traffic isn't a BAD thing if you are talking of concepts. Use of algebraic isn't a fact of nature, or of law. We're talking about concepts and ideas here. If everyone went with the flow, we would have ONLY Microsoft software in the world, now wouldn't we? Instead, we have Linux, or replacements for Microsoft Office. We have Firefox instead of MSIE. We have the Mac instead of Windows XP.

Quote:
o There's also the fact that, due to market pressure and other factors, the number of RPN models in the market is very small, a negligible minority in the calculator market to say the least. Essentially, only one company still makes them, and there are very few models to choose from, namely the HP-12C, HP33S, and HP35s, if we stick to classic RPN, all of them subject to some serious limitations such as an absolute lack of I/O, for instance. So if you're used to classic RPN or want to introduce it to your children, your options are few and, mostly, relatively expensive compared with the algebraic offer.

I agree that the numbers are small, and choices aren't the best. But, it CAN change, as we are seeing with the HP-35. In addition, I notice that you conveniently excluded the HP-50g/49/39 families, which have extensive I/O functionality. And compare favorably to the upper-end TI calcs with applets.

Did you even read the Texas Math Challenge posts earlier this week? Those kids go out and buy used calcs from eBay and craigslist, and use those when the "current" models aren't what they want. A lot of them use the 33s and 50g models. Yes, there aren't as many HP calcs as Casio or TI, but if you want to use RPN, you can certainly find a wealth of options.

Quote:
There's also the distinct possibility that the only company making them decides that they're not worth the effort, their sales aren't enough to justify the costs, and so the powers-that-be might as well decide to write them off the market, thus completely terminating their actual, precarious availability for good.

It's a risk, I admit. At one time in the past, I thought HP did give up on the market. I hope they never do in my lifetime. I choose, however, not to scare myself into using one platform simply because of the possibility of something happening.

Quote:
o It's also a proven fact that RPN tends to generate what could be termed as 'addiction', in the sense that once some people are exposed to it, they'll get hooked to the point where they won't feel comfortable at all having to use any normal, non-RPN calculator, and would be highly inefficient using them, if at all, and would do whatever it takes to avoid using them, as they simply can't cope with algebraic machines anymore, at least not without feeling extremely uncomfortable while doing it.

And this is a reason NOT to use RPN? C'mon, you're reaching... A "proven fact"? I'd love to see the clinical research study you are referring to. Could you please send it to me?

Quote:
o Combining all of these factors, you can see that by introducing your children to RPN, you risk they getting hooked on a paradigm which doesn't resemble what they see printed in their books, doesn't coincide with the procedures and keystrokes taught in class, and forces them to either adapt and convert on the fly what's being taught to their RPN ways, or else burden the teacher with the task of dealing with them and their RPN way of doing things, thus generating inconvenience for everyone there: the teacher, the rest of the class, themselves.

I don't buy it. Even as much as I respect you and love your comments, challenges and articles, this one has me puzzled. It's such a short-sighted, narrow-minded attitude. I am really surprised that your opinion is as you outline it. Sure, you've got some good points here. Some of which I agree with. But I just don't feel the same way as you and I'm kind of surprised that someone as smart as you is so obviously dissing RPN. Choice is good! I'm not a over-the-top RPN fanatic, but I feel strongly that this "choice" needs to get right back into the thick of things in the education market.

Look at it this way: Darwin is right, in that the stronger will survive. The ultimate survivor of this question may be algebraic. But I am not willing to concede the fight this early on. I say we give it to the kids, and let them decide the outcome. I'm willing to trust what comes out over the long run. Give them the choice and let them decide with an educated decision.

You may say "we've already done that!" and yes, that's partially true. But it *has* survived, even after being beaten down and almost exterminated. And it seems to be getting a second chance. I don't give up on my beloved football team simply because they didn't do well the past five years. Give them the opportunity to try again.

Quote:
I know of *many* people, friends of mine and colleagues alike, that suffer from the RPN bug: they simply *can't* use an algebraic calculator with any decent proficiency, to the point that they'd rather take their NIB collectible HP-15C out from the box and into the dusty construction site if necessary if contemplating the possibility of being forced to use any algebraic calc.

I know the same kinds of people. I think, however, if you dug deep enough into their head, you'll find it's not a function of "can't" use it, it's that they don't WANT to use it. Big difference. I don't WANT to use TI calcs, and I don't have any in my house. I would prefer to use HP calcs with RPN, and it does annoy me when I have to borrow an algebraic calc. But I can certainly use them, and proficiently. I just choose not to. There's a big difference.

If, tomorrow, someone took away RPN from every written word, and magically erased every RPN calc from the world, I somehow thing all your friends and mine would manage just fine. They might not like it, but they'd get along.

Quote:
I see this sheer reliance on an obsolete paradigm which surely faces extinction as a dangerous and unnecessary niche adaptation, which can be no good in the long run for the person aflicted with it.

And sliding right down that slippery slope with you, I should give up on Linux, because it can't possibly replace Windows. And I should only learn one or two current programming languages because the others will be extinct in a few years. And I should stop sending emails now because the younger generation says that email is dead and text messaging is going to be it in the future.

Whoa. Pretty free-thinking opinion there...

Quote:
o Also, there's the myth of RPN being perceived as "superior" to algebraic systems, offering this or that "advantage", which "absolutely compensates" and overcomes any alleged disadvantages.

Truly a myth. I don't tell my folks to use RPN because it is superior, but because it's a different way of doing something, and a way that they might find not only easier, but more helpful. I never say to them that it is superior, because that only breeds arrogance and resentment towards RPN.

Quote:
As I've posted in several threads in years past, this is essentially a myth, mostly based in the fact [...]

I agree.

Quote:
But 35 years have passed by, and while classic RPN hasn't barely changed one iota, algebraic models have experienced authentic quantum leaps.

Classic algebraic is the same as it was 35 years ago too. The advances you speak of are -- in some cases -- much like that 4-deep stack. There are accelerators to help with expressions. You can see more on the screen, but that's not a change to algebraic.

What about the changes we've experienced in RPL, or in solver equations? Or that both classes of calcs have seen with CAS? Those "model" changes are as quantum as any of the TI calcs.

Quote:
o Lastly, one of the usual arguments in favor of teaching RPN to kids (or of using RPN in general) is that it allows you a more intimate understanding of the expression you're evaluating: you can see intermediate results, you can check them on the fly, the fact that you must frequently pre-decide the order of evaluation makes you more aware of it all ...

I don't necessarily push these aspects either, but it's just as easy to come up with "usual arguments" as to why algebraic is better, and that doesn't make it any more right either. In fact, you were using many of them yourself. They are not necessarily wrong, but they are not necessarily right. Same for algebraic. I don't see these as big factors in the discussion anyhow.

Quote:
In reality, this is akin to making virtue of necessity. It's not that you can do that with RPN, it's that RPN forces you to do things that way: you must see intermediate results, whether you want or need them or not, you must spend time and effort to pre-decide the order of evaluation whether you want it or not, lest you risk losing items out of the top of the stack, ....,

Algebraic "forces" you to use parenthesis, doesn't it? Algebraic "forces" you to ignore intermediate results, doesn't it? For almost every necessity you can say RPN requires, algebraic has one too.

Quote:
This is similar to the arguments rised in favor of doing calculations with slide rule when the first electronic calculators arrived: many insisted that doing them with the slide rule required a more thorough understanding of the problem, what with re-scaling being constantly needed, and that forced you to think about your numbers and prevent mistakes or erroneously scaled results.

Agreed. I remember those very same discussions when the first calcs came out, and I agree that those discussions are similar to the whole "RPN helps you understand the math" arguments. I don't buy them any more than I bought the slide rule vs calc arguments back then. I had a slide rule and understood it as well as any other basic slide rule user, but I dumped it in a heartbeat for the calc. Not because it was archaic and handicapping, but because the calc was a more productive tool. I'd rather be more productive, getting more done, with more powerful tools, than to say that I "understand" the math more. The TI calcs aren't necessarily any more productive than the HP calcs. Sure, they do some things easier, but I can find a half-dozen things that the HP calcs do more productively.

Quote:
The bottom line is: who cares about the calculations ? About whether intermediate results are seen or not ? About how we do our operations, whether algebraic and parentheses or RPN and stack ? The important thing is that the children understand the problem, understand the algorithms used to solve it, and can correctly write down the necessary expressions that get the results from the initial data.

I don't care about the calculations either. I DO care about choice. About giving kids the ability to push their envelopes, even if it isn't the norm. I'm not saying every kid should learn RPN, or that it should be the standard taught in school. I AM saying that it should be an option.

Quote:
How these expressions are evaluated is absolutely irrelevant. It could be by hand, with an abacus, with a slide rule, with an RPN calculator, with an algebraic calculator, or by saying aloud "Computer: evaluate this, please" in a near future. Who cares !?

In all of those cases, I agree with you. In many others, I hear cynicism and...something else. Not sure what. Not pleasant though. I just hope and pray that our next generation of students don't have the same narrow-minded attitude that you appear to have.

Now THAT is harsh.

thanks,
bruce


#80

Hi again, Bruce:

    First of all, thanks for you detailed and initially interesting reply to my e-mail, much appreciated. Now some brief comments to specific points of it:

    Bruce posted (italics are Bruce's original sentences, all underlining is mine):

      "Your opinion it might be, but I disagree that your assessment is accurate."

        So far so good ... Now for assorted "pearls":

      • "I don't buy it. Even as much as I respect you and love your comments, challenges and articles, this one has me puzzled. It's such a short-sighted, narrow-minded attitude [...]

      • I'm kind of surprised that someone as smart as you is so obviously dissing RPN [...]

      • And sliding right down that slippery slope with you, I should [ ... {lots of absurd, ad-hoc non-sequiturs} ...] Whoa. Pretty free-thinking opinion there ... [...]

      • In all of those cases, I agree with you. In many others, I hear cynicism and...something else. Not sure what. Not pleasant though. I just hope and pray
        that our next generation of students don't have the same narrow-minded attitude that you appear to have. [...]

          Now that's crossing the line as far as I'm concerned. After a decent beginning, you seem to become hotter and hotter by the minute till you resort to a bunch of ad-hominen attacks, adscribing to me all sorts of negative opinions and attitudes which you see fit, including the string of preposterous non-sequiturs (after "slippery road" in your original message) as if I would agree with such nonsense, and finally accusing me of "cynicism" and "something else" which also happens to be "not pleasant", plus "narrow-minded" attitude, and what else.

          That I consider akin to name-calling and a blatant disrespect to me and my stated points, which you might not share or even positively dislike but in a civilized argument you are required to respect, both.

          I don't remember having included in my posted message a single word about you, your frame of mind, or your attitudes, good or bad, so I don't quite see why a supposedly intelligent and educated person such as you would have to resort to such low levels to discredit an opinion you don't agree with.

        "Now THAT is harsh."

          Indeed. This argument is finished as far as I'm concerned and I would ask you to please refrain from using my name to put in my mouth or mind opinions which I haven't explicitly uttered or contemplated, as you do several messages below in this same thread while replying to some other message.

          Also, in so far as you don't seem to have an attitude of respect towards me and my ideas, even if you don't share them, I would be obligued if you would refrain from referring to me or my ideas or the ideas you imagine I have. I'll do the same with you.

      Thanks in advance and

Best regards from V.


#81

Everyone is entitled to an opinion, even me. Maybe its your choice of words, or the way you wrote it or whatever, but your statements often make it sound like what you say is fact, and what others think (or say) differs from that fact.

"...my assessment is an accurate one..."

Why is my assessment not an accurate one too? Am I not allowed to discuss your message, point-by-point, and offer a differing opinion?

"...it's a proven fact that RPN..."

I'm not aware of that fact, and you still haven't told me where you got that from. Why must I assume your fact is correct? I have the right to ask for clarification or proof. All of my comments were expressing an opinion, and sharing information, not coming to a conclusion.

None of my examples were any more non-sequiturs than yours, since you were the one who chose certain examples such as driving on the wrong side of the road, etc. You brought up the slippery slope that once you introduce RPN to kids, they risk getting hooked, which leads to adaption, etc. Where did THAT line of logic reasoning come from? If you're allowed to jump to conclusions, I certainly can too.

Heck, maybe you just don't like someone pushing back on you, expressing a different opinion and trying to point out other things to consider. None of those were attacks on you (whether you think so or not), and in fact I went out of my way to tell you that I respect you and always have. I still do. I just have a different opinion, and I have the right to express it.

I will certainly honor your request, and I won't put words in your mouth. I will always, however, reserve the right to respond in kind to postings -- yours or others -- using original words, and expressing my own opinions. Perhaps I prefer to be more blunt in my replies at times. It's just as easy for someone to express a "tone" in messages that achieve a similar result. I prefer to just say it and lay it on the table. Let everyone make up their own mind, you know?

thanks,
bruce

#82

By the by, I'd be more than pleased to buy you a pint at the conference and we can laugh at all this, if you're up for it. No harm intended.

thanks,
bruce

#83

Programming languages?

You mean you straddle your students with a dead language like Pascal because you aren't innovative enough to teach them C, C++, Java or other current languages?
What does Pascal offer that can't be taught in the other languages?
Data structures? Nope... Variables? Nope... Ease of learning? Hah!

It is past the time for Computer Science teachers to let go of some "teaching languages" and start TEACHING LANGUAGES!

I didn't have to learn Ancient Hebrew, Ancient Greek, or Latin to learn how to speak English. So why fill up your students brains with Pascal before you teach them something that is useful in the job market?

(Now I do admit that learning the ancestral languages of my tongue is helpful in better understanding English, but I don't feel it should be a pre-requisite for kindergarten).

Sure you can teach them MIPS or 68K as assembly languages, for there is a growing market for programming embedded devices.

The oft used rebuttal by comp sci teachers is, "its easier to teach Pascal". Why is it easier, is it because that is what the teacher learned, and they are quite comfortable in their ivory tower?

Okay, I'm through ranting...

(for now)

Ren

dona nobis pacem


#84

Ren, regarding teaching programming languages, I would make a distinction between teaching students who aspire to be programmers versus other liberal arts students who just want an introduction to programming, but won't make it their living. For the programmers-to-be, I'd teach the popular languages plus show the kids some older languages so they get an appreciation for how programming has evolved over time. For the non-programmer who just wants to see a little of what programming is about, Kemeny and Kurtz had it right in 1964: BASIC. Kids can learn the essentials of vanilla BASIC in an hour, and use it productively in a short time.

#85

Ren --

I think you confused me with someone else. I do NOT teach Pascal, and I have resisted that abominable language since the day it was taught to ME back in college. In fact, I resent your comment that I "straddle" anyone with things that aren't "innovative". I don't know how you got that from my post, but maybe you have some pent-up aggression towards instructors in your past??

My point was that if mere dominance is the reason for selection of what to teach in higher-ed, then we would have schools ONLY teaching Java and C++. Fortunately, that's not the case. To be so narrow minded as to teach one or two styles of programming would be a travesty of education, and it does nothing for upcoming programmers.

Many universities now teach other programming languages like Visual Basic, C#, ColdFusion, Perl, Python, PHP, Ada, PL/SQL and others. True, they are not the dominant languages, but by getting students exposed to them, the pros and cons, the trials and tribulations, etc., the student starts to understand why there are CHOICES in the world.

There were a ton of Pascal programmers on the market after the 1980's, and that was because it was the language being taught. AND it resulted in some piss-poor code out there. The reason why we HAVE languages like C++, Java and C# is because finally people started understanding what was wrong with the older versions, and realizing that there are choices. I.e., make it better.

I "collect" programming languages like other people collect calculators. I know more than 34 programming languages, and I'd say I'm more than fluent in at least 8-10 of them. One of the reasons why I got as far in my career as I did is because I can offer clients that breadth of knowledge -- that breadth of CHOICE -- to pick the right solution with the right tools. If my toolbox only had two options in it (or, sadly, as Valentin would want: ONE choice), I am limited in what I can do.

I won't go into a discussion of why it's valuable to learn the historical languages (both spoken and programming) if you want to truly understand more modern languages. In my mind, that argument doesn't apply to all students -- it applies to those who are truly heading down the computer science path, not the IT path. It's easy enough to get a career as a decent programmer when you only know a couple languages and don't desire to dig deeper. But when I want someone who is a compiler designer, or who writes code generators or run-times, I do NOT seek those IT people out; I search out someone with a computer science background, who HAS gone and studied those old languages and understands why decisions are as they are today.

I know I'm kind of mixing calcs with programming, but I draw a parallel between the two. If we provide kids with only one way of learning to do math, they only know that one way. If we offer them the choice -- even if it is a less-used choice -- then some of them are going to have a lightbulb moment and move beyond their peers.

If I were teaching math to teens, I could happy/content with teaching the vast majority of them the things they need to succeed, using TI calcs. But... It is the rare kid who brings in that HP calc to class who I would spend extra time with. That kid is likely to be the one who makes a difference in this world. Instead of blending into the woodwork of normalcy, that kid is probably going to be the one who stands out in our world. NOT because he or she has an HP calc, but because he or she chose to try a different road.

For example, in one of my music classes recently, a student asked if she could write her term papers in poetry instead of straight prose. The prof thought for a moment and asked her to write an example of what it would look like with the topic being how the piano had evolved over the years. She did, and he was VERY impressed. It wasn't a flippant work, just trying to be cute or artistic. It conveyed exactly what he asked, with factual content, and yet it was written in a poetic (??) style. She got her wish and wrote all of her papers in that style.

She took a stance to try something out of the box. It was probably much harder than a traditional paper. Yet because she had CHOICES and didn't feel like she had to do it one particular way, she made a difference to all of us in class, including the prof. She is the kind of person who I expect will stand out in our world.

Giving up on RPN simply because algebraic is the dominant tool is sad to me. Not for nostalgic reasons, but because I believe it is short-sighted, and shows me that people would rather -- as YOU put it -- go the "easier" route. Personally, I'd rather challenge myself, and my students, and give them the option.

thanks,
bruce


#86

Quote:
If I were teaching math to teens, I could happy/content with teaching the vast majority of them the things they need to succeed, using TI calcs. But... It is the rare kid who brings in that HP calc to class who I would spend extra time with. That kid is likely to be the one who makes a difference in this world. Instead of blending into the woodwork of normalcy, that kid is probably going to be the one who stands out in our world. NOT because he or she has an HP calc, but because he or she chose to try a different road.

I had a teacher like that. This was in about 1980, and I had a programmable calculator (a TI SR-52, not an HP unfortunately). We were learning how to solve systems of equations, and I had programmed the algorithm (Gaussian elimination) into the SR-52, from scratch. It worked for 2 or 3 equations (since there wasn't enough memory to hold the coefficients for more than 3), but it was implemented to solve the general case. I asked him if I could use it (and the program) on my math tests, and he agreed. Another student overheard this and objected, to which my teacher responded, "if he understands the method well enough to program the calculator to do it, he deserves to be able to use it."

Basically, instead of forcing me to conform to the way everyone else did it, he let me take advantage of the skill and initiative I'd shown. That was probably a more valuable lesson than knowing how to solve systems of equations.

Stefan


#87

Good point. In fact, back when I was in high-school (same timeframe!), using calculators of ANY kind wasn't permitted, let alone HP calcs. I finally successfully argued with one of my teachers to let me use my HP-25c in class because if I knew the algorithms and technique well enough to program it, I certainly could do it on paper. After showing him how I did it, he agreed.

Like you, I think this was one of the more valuable lessons learned.

Did we go to the same school? ;-)

thanks,
bruce

Edited: 23 Aug 2007, 1:40 p.m.

#88

Bruce,

When I saw the phrase in your earlier posting "teaching languages",
I went ballistic (too much caffiene). After I'd posted, I re-read your post and saw it for what you intended. While I didn't mean to attack you personally, it was your posting that triggered me to hit the reply key. Reading your follow-up to my rant, I agree with much of what you wrote.

I humbly apologize for not reading your post clearly before replying, and I'm sorry I made you look guilty of lazy teaching (of which you are not).

Over the years of being a student, I've gotten touchy (over-sensitive) to instruction that didn't make sense to me, busy work as it were, for students, work that distracted from underlying goal of the course.
Often when instructors were challenged about that, the "we've always done it this way" reply was common.

On the subject of BASIC, well I suppose in the form of Visual BASIC it can be argued (ooh, I'm good at arguing today!) that BASIC is NOT a dead language. (I also think the embedded processor BASIC-stamp further supports that BASIC is alive). I'm not opposed to teaching BASIC, but it too was the first language I learned, and so I don't want my prejudice for it (I have a few you may have noticed B^) to automatically impose it on any possible student, just because it would be the easy route for me to teach. Again, I'm not criticizing BASIC, or your response, just doing a bit of self evaluation.

Ren

dona nobis pacem


#89

Thanks, Ren. I figured you might have had some pent-up anger ;-), and I fully understand it in relation to Pascal.

I, like you, was always confused and driven crazy by the push to teach Pascal as if it were the panacea for all programming. In reality, it was inconsistent, slow, painful and sadly missing many important concepts that existed in other languages at the time.

I'm sure there were reasons at the time, but I never bought into them. It still bugs me when a university teaches Pascal.

I totally agree about work done merely because it has always been that way, or to just "rote" people into doing things. The profs who spend the time to teach a subject and make sure you understand it, and then use it as a leap to other things, are worth their weight in gold.

BTW, I love mutzing with the Basic Stamp. Brings me back to my old embedded systems days, and it just feels so...fun! :-)

thanks,
bruce

#90

My first calculator was an RPN four-function model, the Novus 650 "Mathbox". It had a six digit LED display, and basically only did integer arithmetic (there was a permanent decimal point displayed between the second and third digits from the right). I think it cost $20. I don't recall exactly when I got it, but it was some time between the 4th and 7th grade (1973 to 1976).

I turned out just fine, thank you very much.

Stefan


#91

Hi, Stefan:

Stefan wrote:

    "I turned out just fine, thank you very much."

      You're welcome.
Best regards from V.
#92

Buenas tardes, Valentin,

your post shall be taken with a grain of salt. IMHO, the average student (i.e. escolar, Schüler) shall get what the teacher recommends and/or the majority of his/her classmates use. This is to guarantee optimum support during lessons. Nowadays this will be some TI or Casio.

If, however, you know you have a little math genius at home, who enjoys math instead of struggling with it, why not show him/her something which will make calculating life a little easier for the price of another way of thinking? Remember the translation of "Mathematika" is "learning to think".

The average student (i.e. estudiante, Student), however, should be sufficiently mature to select the best tool supporting his/her studies, whatever it's logic system may be.

Just my 20 Milli-Euros.

BTW, what bothers me: How do you Americans differentiate between students and students (please see above)??


#93

Quote:

BTW, what bothers me: How do you Americans differentiate between students and students (please see above)??


Güten nacht (or is it morgen there now?), my friend Walter. This is easy. There are two type of student in America. Those that have to be, and those that want to be. The later have a light in there eyes that is different. Most likely much like yours, mine and the rest of those in this group. The former, is more like the student who just want to get done with school so "life is no a hassle" and realize it really is just beginning for them (hassle that is). The most later student I pray for, the former, I thank God for.
#94

Quote:
... BTW, what bothers me: How do you Americans differentiate between students and students (please see above)??

Age?

Level? (Secondary or postsecondary or graduate?)

For secondary "students", often another word can be used, "pupils". In some instances, and you'll have to read the (American) English context, "student" means one studying to be a scholar. I suspect, at least in America, you may generally need a master's (wow!) or doctorate degree (holy smoke, what's he, crazy??) to be called a scholar. If only a baccalaureate, I think it's just "college grad".

Maybe you need to master (or in the case of some our posters here who own screwdrivers and soldering irons, doctor) a HP RPN scientific programmable calculator? Yeah, I like this one.

#95

Hi, Walter:

    Thanks for your comments, please read my answer to Bruce Bergman above, which equally well applies to what you say in your post.
Best regards from V.

#96

Buenas noches, Valentin,

after reading the major part of it, I hope you did not mean that this very personal discussion above "equally well applies to what you say in your post". But maybe I took the wrong answer? Anyway, I'm not in the mood of arguing, so I let you get away with it today. Sleep well!


#97

Hi, Walter:

Walter posted:

    "After reading the major part of it, I hope you did not mean that this very personal discussion above "equally well applies to what you say in your post". But maybe I took the wrong answer?

      No of course it does not apply to you and yes, it seems you've read the wrong answer. I was specifically referring to message #17, my second post in this thread (my first one, to which you replied initially, is #15).

      You've probably read my third post in the thread, (in which I regretted the non-sequiturs and ad-hominen attacks issued by some other poster) instead of the second one, in which I ellaborated my points in much greater detail, specially when compared with my terse, 2-line initial message.


    If you then go on to read my second message (#17 it was) and have any further comments, please don't hesitate to let me know. Thanks for your continued kindness and

Best regards from V.

#98

Buenas tardes, Valentin,

besides the danger of "addiction" you claim, I do not see in your response #17 too much difference to my post above - besides you like to write longer posts than me.

I would rather claim people get accustomed to RPN than addicted. And, the older we become the less we like (or are able) to change our dear customs. Nevertheless, I'd still rate RPN being "better" than ALG, provided the stack size is set to 6 levels for real "sans soucis" calculations. But, to repeat it, I would not force an average pupil to use it.

Once again, just my 20 Milli-Euros :)

Edited: 24 Aug 2007, 5:14 p.m.

#99

Dr B…

Actually, I started with RPN, not algebraic. The first calculator I ever used was my dad's HP-35, which he got in late 1972 when I was in 9th grade. RPN is so natural, it took almost no time for either of us to learn how to use it. Natural? Sure, once you realize that it is impossible to perform an operation on one or two numbers without first having the numbers, then postfix becomes natural. All other syntactical methods must "store" the operation waiting for the number.

Fred


I agree. I started out with a simple 4 function calculator, but when it was time to step up at age 13, I bought an HP 41CV and learnt how to use it and program it by myself. I sometimes had to use an algebraic calculator because no-one knew what an HP 41 was, but I still think RPN is much easier to use.

My GF needed a financial calculator so I offered her my spare HP 12C, but she thought RPN was too complicated (having never used it). So I bought her a TI Business Analyst. After seeing me use the HP more quickly, she has given up on it and wants an HP 12C as well.

I really do think that RPN is easier to use and more in tune with how mathematics is. Algebraic is better for those who don't understand, and simply want to key in formulas exactly the way they see them on the page. The latter people then tend to trip up when they don't have access to a calculator.


Quote:
I really do think that RPN is easier to use and more in tune with how mathematics is. Algebraic is better for those who don't understand, and simply want to key in formulas exactly the way they see them on the page.

And that's where algebraic diverges from actual life & work in engineering. Schools focus too much on memorizing equations and not on understanding what's behind them. Very often there won't be a formula written down! I find myself usually having to think through what's actually happening while punching buttons, and it would take me longer if I had to form a complete equation before beginning the calculation or writing a short program. If I use my HP-71 as a calculator instead of the 41, I use the cursor keys a lot to go forward and back as I form the equation, and then I have to be careful about the pile of parentheses. (I hate the 71's "calc" mode too, and never use it.)

Fred wrote:

Quote:

Actually, I started with RPN, not algebraic. The first calculator I ever used was my dad's HP-35, which he got in late 1972 when I was in 9th grade.
Fred


Fred,

Do you mean you didn't learn to add, subtract, multiply, and divide integers until the 9th Grade?

B^)

I'm sure you had learned math[s] algebraically long before the 9th grade. At that time you were "introduced" to RPN and electronic calculators.

(Boy, am I in a crabby mood today, or what?)

B^)

Ren

dona nobis pacem


Ren…

Arithemetic is done RPN in the brain, even though it is written algebraically. :-)

Fred

Quote:
Fred wrote

Do you mean you didn't learn to add, subtract, multiply, and divide integers until the 9th Grade?

B^)

I'm sure you had learned math[s] algebraically long before the 9th grade.


Come to think of it, we ALL probably learned RPN without knowing it. For instance, take the problem of adding, subtracting or multiplying two "large" numbers (to a third grader), i.e., 23 and 146. First, we write down the two numbers stacked:

    23
146
------

THEN place the appropriate symbol for the problem,

    23
+146
-----

However, I agree with Valentin...I'm "forced" to use TI calcs in class since they have the best overhead for classroom demonstrations, 29 of 30 students have a TI, and a used TI-84 can be found for $30 (a VERY capable calculator). It's not until I teach differential equations or linear algebra that I start taking my HP into class making a few converts. But again, in ANY class the understanding and correct synthesis of the problem is more important than the precisely correct answer.

Chuck

From what I've seen with my grandniece and grandnephew, they found using RPN calculators much more intuitive than the algebraic models that they'd used before. Of course, they were just getting started with using calculators for anything more than basic arithmetic, so they weren't yet too indoctrinated into using any sort of algebraic interface.

My two concerns with children learning to use RPN models would be first that it may well be difficult for them to get help in using them, and second that RPN models may stop being manufactured at some time in the future.

Personally, my first experiences with "calculators" were with "adding machines".

Regards,
James


James,

Re concern #2: Just buy a bunch of them! My HP12C has lasted over 20 years of abuse and still works perfectly. I have a couple of spares, just in case the original dies.

Bink

6 years ago I started working as a physics teacher at a high school in Luxembourg. The young people I am teaching physics to are aged from 14 to 20.

Up to now, no one, absolutely no one of the pupils/students I have worked with had an RPN calculator!

The calculators that ore most used are the basic scientifics from Casio and TI. Some students have Casios with the "Natural Textbook Display". They like it a lot because it is so easy to copy written problems to the display of the calculator. No way to worry about parentheses and above all, the meaning of what they are calculating.

For me it is impossible to introduce RPN calculators in my course:

  • All students have their cheap 10 to 15 Euro basic calculator. They are not willing to spend some extra 60 to 100 Euro for an RPN calculator that is hardly available in stores here in Luxembourg.
  • They don't know RPN and cannot understand the advantage of not having parentheses. The problem is that you have to know some basic rules of mathematics in order to use a RPN calculator. Or for most of them, mathematics is something they don't want to learn, no way!
  • The main problem is, that they should have to learn RPN earlier, at least at the beginning of their high school career when they are 12 years old. Or there we have another problem. Most mathematics teachers I know don't even use RPN! Most of them even think that it is too complicated! This really is the wrong start.
  • Nevertheless, many of my students are amazed how fast I can calculate with those strange machines at the blackboard!

So a simple RPN calculator for kids would be a good start towards illumination of those dark minds!


I must admit, right before I decided to spend the then (a looonnngg time ago) $124 USD for a HP-34C, the decision did require a bit of persuasion.

The major reason for any resistance was the relative higher cost of the HP machines over the TI ones (which seems to be less true today). But some very intelligent graduate students who happened to be also my instructors and supervisors convinced me (a professor also had the same high opinion of HP's RPN calculators, but was far less persuasive than the grad students) of the superior power of RPN once it was mastered and the superior quality of HP construction (then VERY true).

I am glad I listened to them; I still enjoy using RPN programmables.


If the expression is already written down somewhere I found that a calculator with "text book entry" is the easiest to use. If I am solving something like a word problem and I have not written down an expression then RPN or RPL is easiest. The algebraic type is OK but I often forgot the extra parenthesis when I have an expression that use the bar for divide or one that use the radical sign.

My humble post will not compare to the comprehensive and eloquent discussions above. I only would like to add the following observation:

I’ve tutored many children and adults, all of whom used TI hardware, through algebra (Junior High, High School, and College Algebra). Many of them had used their TI for several years before entering the course. All were very proficient at manipulating their calculators, but none of them, not a single one, knew the order of operations.

I have seen algebraic entry systems used in education become a crutch over and over again.. For the few kids who actually get it, more power to them. But the vast majority learn how to get the “Answer” never having a clue what the “Solution” is.

In the hands of a person with sound math skills, the RPN/Algebraic choice is truly a matter of personal preference. But for a student, I believe algebraic provides way too much automation.

I’d never presume to speak for all children, but my boy will carry an RPN until he’s able to buy his own. If he encounters a professor that requires other hardware, he’ll carry both. I don’t mind automation lifting the arithmetic burden, but I insist that he does the MATH.

I recently read Mr. Albillo’s story, “Time Voyager”. I enjoyed it immensely. If I may, I have a question for the author: If the story featured an algebraic machine, which one would it be and why?

Very respectfully,

David


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