The Future of RPN Calculators 301
Noksagt writes "HP's recent release of the 33s won't be the last RPN calculator. Former HPers at Hydrix are hyping an impressive Linux-based PDA/calculator, named Qonos. They have a survey up regarding features, etc. More information can be found at comp.sys.hp48 or The Museum of HP Calculators.
A new open hardware project called OpenRPN has also begun. Their mission is to produce horizontal and vertical format scientific RPN calcs and later a graphing calc."
The future of RPN calculators... (Score:5, Insightful)
The Masses don't understand RPN, don't understand why anyone would want to use a "backwards" syntax, and aren't interested in listening to us nerds when we explain the very real benefits of grokking stack-based systems.
Re:The future of RPN calculators... (Score:5, Insightful)
I teach calculus to students who use the TI, and so many more students just do not get the chain rule. It is amazing. Moreover, it is damn near impossible to try to connect the idea to the way they think about functions and the way they key them into the calculator. The tools we use really can constrain the way we think, and rpn calculators really make you back up and rethink what a function is.
Re:The future of RPN calculators... (Score:4, Insightful)
dx/dy = dx/dt * dt/dy
Since you teach calculus, I'll point out that this is a serious question - what's not to understand?
Re:The future of RPN calculators... (Score:2, Informative)
d/dx f(g(x)) = f'(g(x)) * g'(x)
Re:The future of RPN calculators... (Score:3, Insightful)
Re:The future of RPN calculators... (Score:5, Informative)
Re:The future of RPN calculators... (Score:3, Informative)
Out of curiou
Re:The future of RPN calculators... (Score:3, Interesting)
These kinds of subtleties can be quite hard for non-native English speakers to discern but you'll figure it out eventually.
Re:The future of RPN calculators... (Score:5, Informative)
Second, you've committed the atrocious sin of mixing Leibniz notation with Newton prime notation. What a horrific mess you've created.
The proper way to write it would be:
h(x) = f(g(x))
h'(x) = f'(g(x))*g'(x)
I think this should help explain why the Leibniz notation is so popular, because in the Newtonian notation, a prime can only bind to a name, not an arbitrary algebraic expression. Hence you are required to introduce the additional function h(x) just to allow the notation to work.
Anyway, you're hardly qualified to school us in calculus.
Re:The future of RPN calculators... (Score:4, Insightful)
(whine)
But DAD! This is how ALL the cool calculus textbook writers are doing it these days!
(/whine)
Leibniz notation is introduced in all the calc textbooks I've read with the STUPID idea that even though it LOOKS like a fraction, you can't TREAT treat it like a fraction. I suppose this is done to preserve rigor, but it is a STUPID pedagogical technique. End rant.
The functional notation f'(x) is useful, as is the differential notation dy/dx. Mixing them gives you the worst of both worlds.
Just to pick a nit - IIRC, Newton used a dot notation, which this screen is too limited to display. Here's an attempt at explanation. If x were a function, then x with a dot over it would be the first derivative, and x with two dots over it(like an umlaut) would be the second derivative. I don't recall where the 'prime' notation came from.
Anyway, you're hardly qualified to school us in calculus.
Now, don't be hard on the boy, just because his teacher is everything we've come to expect from the public education system...
Re:The future of RPN calculators... (Score:5, Insightful)
LOL.
Spoken like somebody who has only taken the advanced math classes.
I mean that mostly in a good way, but you have obviously not examined the "normal" student in detail. A lot of people (scarily, possibly even the majority) graduate high school without really being able to add 17/28 + 87/98. Of those who can, few of them can explain it correctly. Of those who can, most of them lose it quickly.
I wish it was an "intuitively obvious rule to anyone who has completed sixth grade".
Re:The future of RPN calculators... (Score:2)
OK, obviously I exaggerate a bit. Frankly, though, if you can multiply fractions (which I THINK I learned in 6th grade), you can comprehend the chain rule. In my original posting, it should be apparent that the "dt" terms out (or equate to one, if you prefer). Anyone who, on their first day of calculus class, can't be convinced that the chain rule is true should be sent back for remedial arithmetic instruction.
Note that 'apparently true' is not the same as 'rigorously proven true' - but the differenti
Re:The future of RPN calculators... (Score:4, Funny)
It's 1.4948979591836734693877551020408.
Re:The future of RPN calculators... (Score:2)
??? - More Detail, please. (Score:4, Interesting)
Re:??? - More Detail, please. (Score:3, Informative)
If you wanted to punch the same equation into a RPN calculator, you would need to break it up the same way. This is a pretty trivial example, but if you've used RPN (I haven't used it much at all) then I think you'll see what the parent meant.
P.S. - Real sophomores know how to spell it. ;)
Re: ??? - More Detail, please. (Score:5, Insightful)
I wouldn't worry too much about a flash calculator, either. The important things in mathematics go on in your head, and on paper. The basic arithmetic functions are jolly useful, and the trig functions (ideally including hyperbolic ones) can be quite handy, but if you can't work out the graph of a function yourself, then a calculator isn't really going to help you.
What I found helpful when learning calculus was to think of it in mechanical terms where possible. Functions and graphs can be a bit abstract, but calculus is really about rates of change, and I found that thinking in terms of speeds and accelerations tended to give me a good mental picture of what was going on, at least to start with.
Re:??? - More Detail, please. (Score:5, Interesting)
After having used a TI-89, then an HP-49G, when I try going back to the TI-89 for some purpose (maybe a game, or a program i once made), I really start to notice how annoying and slow the 89's UI is.
The HP is also much more customizable. The ability to remap the keyboard is quick, easy, and built in. There are 128 system flags for changing user settings, accessible via the MODES menu. The HP has no limit to the depth of the directory tree. Its menus are better -- they are at the bottom of the screen, somewhat like the TI-85 and Ti-86's menus, rather than having to type Shift MATH 4 4 every time you need to use a specific function.
One of the neatest things is programming. Its programming language, Reverse Polish Lisp, is simple yet powerful. Plus, it has a built-in compiler for System Reverse Polish Lisp, and ASM.
Plus, text-editing on the HP 49G/G+ is much, much easier. When in ALPHA mode, one can type both letters and numbers because the number pad has no letters on it.
I used it for BC Calculus this year, and it easily served my needs.
Re:??? - More Detail, please. (Score:3, Interesting)
[Y=][CLEAR][SIN][X][GRAPH]
Isn't this five keys, vs eight? I can't talk about the other things you mentioned (which might be better), but the graphing example wasn't helping your case much.
Re:??? - More Detail, please. (Score:5, Interesting)
There is a real-world situation for this: to learn to walk a tight-rope, bring it down until it's 6" off the floor. Most people have no problems practicing that way. But it's the same rope. The only difference is in your mind.
The only "real math" classes I took in college were Calc III, Advanced Calc, and DiffEq. I hated real math that much. Having studied under Hofstadter and Erdos while in high school made me realize I needed to be open & free in my thinking - abstract algebra, group theory, and Galois' work made me realize how much more suited I was for "pure math". It's so open and you can create anything you want to with your imagination.
I just wish the regular high school classes taught students something other than "real math" algebra and calculus so students could see a difference and which is better suited for them.
Re:The future of RPN calculators... (Score:4, Insightful)
The market probably won't be huge, but that has nothing to do with it's RPN-ness or Linux-ness. That has to do with relatively small numbers of folks who need a powerful math appliance.
On the other hand, this has the potential to be the iPod of the Mathematically Inclined. If the software and industrial design are done well, it has serious hope to be a hit on college campuses, as well as with a variety of technical professionals.
Re:The future of RPN calculators... (Score:4, Insightful)
The benefits are quantitative in that it is less keystrokes to evaluate a given expression. Don't sell it in terms of "grokking", because that gets into personal psychology which cannot be easily measured. Instead, count keystrokes. "You can finish more of your exam in the given time-space" for example.
Re:The future of RPN calculators... (Score:3, Insightful)
Interestingly, I have noticed that after having adopted RPN and used it for
Qonos???? (Score:5, Funny)
Re:Qonos???? (Score:2)
Same planet.
Re:Qonos???? (Score:2)
1. Kronos
2. Q'onos
3. Qo'noS
Not sure why the 'r' comes and goes, though.
Re:Qonos???? (Score:4, Informative)
The reason the 'r' comes and goes is because the 'Q', in Klingon, is sort of like an over done 'k' in English. It's pronounced toward the back of the mouth. The net effect is vaguely like a "kr" sound in English.
So "Kronos" is sort of a phonemic transcription of what "Qo'noS" would sound like.
woah! (Score:2)
i guess it may be useful for some people who need the extra features or want the fancy gui. but really, who needs stereo audio input/output?
I still have an RPN calculator (Score:3, Interesting)
maxima (Score:5, Informative)
If it could be put into a calculator, that would rock.
There are a bunch of others (Score:3, Informative)
There are a bunch of others. My favorite is PARI-GP [parigp-home.de].
Bad title (Score:5, Funny)
RPN Calculators Future of the
Re:Bad title (Score:5, Funny)
Well, more accurately it should be "Calcuators RPN Future the of", but if I were to point that out I'd be basically admitting how much of a geek I am.
Re:Bad title (Score:2)
Re:Bad title (Score:2)
(Er. Why shouldn't adjectives and prepositions follow RPN rules? I guess for that statement to work "RPN" would have to modify its argument and "and" would have to be interpreted as some sort of Perl 6-style quantum superposition...)
oh my gosh (Score:2, Funny)
What is really scary is that I read that sentence without noticing anything wrong with it. I guess that's what happens to RPN users...
Re:oh my gosh (Score:3, Funny)
Zaurus Support? (Score:2, Interesting)
If it's using the same OS, on very similar hardware, the Zaurus would be a good development/prototype platform. And, it would give us Zaurus owners a good calculator option.
HP 200LX is the best RPN calculator I've ever had (Score:2)
200LX forever!
Includes graphing on a large screen, full keyboard, etc.
And runs DOS 5.0!
Linux based RPN calculator ... (Score:5, Funny)
Other obligatory comments:
More details and pictures (Score:5, Informative)
Quote:
Operating system:
eCos, running in 512KB SRAM and providing one month of battery life
Linux, running in 64MB of SDRAM and providing considerably more than a day of battery life
Other software:
Emulation of both the HP 49G and the TI-89
Advanced math software: Gnuplot, Giac/Xcas (supposedly better than Maple), MathsExplorer
PDA software: calendar, tasks, notes, time management
Datalogging capabilities
Processor:
Intel PXA 263 XScale processor, running at 400 MHz
32MB of on-chip flash memory
32-bit data bus
Display:
Grayscale 3" 320x240
Full support already exists for a color screen to be offered at a later date
Other hardware:
Mono speaker and microphone
Stereo audio input and ouput ports
Keyboard with tactile feedback designed for fast, accurate data entry
Compact Flash Type II slot
SDIO slot
IrDA port
USB client and host ports, supporting external keyboards, webcams, and other devices
Optional sled:
Vernier probe compatible
8 analog I/O channels
16 digital/sonic I/O channels
Extra high-capacity lithium ion battery
DB-9 serial port
Price:
Over US$350
Re:More details and pictures (Score:2)
Did anyone else notice this? Just how much is "considerable"?
Natural it isn't (Score:4, Insightful)
On the other hand, RPN does inspire near-religious devotion in some, especially those who used the early HP calculators back in the 70's. My engineer dad would have killed for one of those back in '74 or so, but they were too expensive at the time.
Re:Natural it isn't (Score:3, Interesting)
Integration in PDA/Calculator (Score:5, Insightful)
Here is a short list of some planned features:
*Philips LMC210x ARM7 CPU
*Flashable ROM
*MMC/SD expansion card support
*20 digit accuracy
*USB connectivity
*Several forms of I/O
*3"x5" PCB for internal expansions/modules
*Hi-Resolution LCDs
*All aluminum watertight body
*Molded-through keytops (customized sets will come standard)
*High-durability anodized finish
*Customizable keyboard overlays
*Positive tactile keys
*Reverse RPL compatability
*A nice thick manual
This sounds just like the PDA I would Love to have which is of course the point here.
My single question is one of integration in that I do not want to carry a full-featured Calculator and a PDA I just want the PDA itself yet with this awesome calculator function integrated. Where does the line exist anymore between PDAs and Calculators especially Linux powered devices?
Re:Integration in PDA/Calculator (Score:3, Informative)
"Linux-based calculator" (Score:5, Funny)
Is it just me, or does that have the same ring as "fuel/air explosive-based cigarette lighter"?
No one ever forgot to return my RPN calculator (Score:5, Funny)
This scared everyone away, and they went on to borrow someone else's calculator. I didn't have any trouble with people "forgetting" to return the calculator, I still have it to this day. Thanks, HP!
For HP to sell more RPN calculators (Score:4, Insightful)
HP made a mistake... (Score:2)
Re:HP made a mistake... (Score:2)
But yes... I do love my HP calculators
My $2E-2 (Score:5, Insightful)
I don't want my calculator to be my PDA. I have a PDA for that. They're different devices with different interfaces and should be used for different things. I put an RPN calculator on my Palm and, although I can use it, it's awkward and clunky. I use it only when I have no other choice.
I don't want a graphing calculator. I like my one line of text. If I need to graph anything, then I'm probably doing it for a complicated reason, and I'll fire up Matlab or Origin at my desktop. My calculator is for, just that, calculating.
The website brags that this thing has a whole month of battery life in it's low-power mode. Big fricking deal. I bought my HP in about 1990. I have replaced the batteries in it exactly ONCE. There's nothing more useless than a calculator that you've picked up and realized you forgot to plug it in last night to recharge it, and it's dead.
I don't want a fold-out keyboard that's probably fairly fragile and won't last too long. I want something sturdy that will stand up to significant, continuous use for years to come.
Why can't someone just build a good calculator that does what it's supposed to, and not some calculator / PDA / laptop / Borg monstrosity?
Re:My $2E-2 (Score:3, Interesting)
If they made a 32S with 4 visible lines of stack, I could die and go to calculator heaven. Best calculator ever
Re:My $2E-2 (Score:2)
Obvious answer. (Score:3, Insightful)
Thus, building it again isn't likely to be profitable.
Re:My $2E-2 (Score:2)
basic math. I wish someone did a calculator with
a full matlab environment (simulink and all). That
would blow away any option on the market whether
TI or HP or Casio. This would redefine back-of-the-
envelope calculations.
Re:My $2E-2 (Score:3, Insightful)
I don't want my calculator to do mediocre graphing or mediocre symbolic logic or mediocre numerical analysis or mediocre monte carlo simulation, yadda yadda yadda - for anything complicated, I'm going to use my workstation with a big display and high end so
Re:My $2E-2 (Score:3, Insightful)
Because stable and reliable doesn't convey "status" like the "latest IN gadget", and thus marketers don't know what to do with it.
When's the last time you saw an ad for anything that featured detailed description of the actual merits of the product, as opposed to pretty people having fun/doing work/both? I've never heard a commercial for a car say, for example, talk
Shameless Plug (Score:3, Interesting)
ghsiloP [sourceforge.net]
I discovered last night that the stack doesn't scroll when you add lots of values, but I'll fix that soon.
Re:Shameless Plug (Score:3, Informative)
Re:Shameless Plug (Score:3, Informative)
Guess (Score:2, Funny)
Nostalgia (Score:2)
After playing with the device for a few weeks, I built a data cable and, about half way into the trimster, did load an IR library onto the thing (think remote control emulation). Man, we had a lot of fun with that thing (my High School had cable TVs in every room and in the halls so we had a lot of fun).
And I still have that calculator and use
this needs linux? (Score:5, Insightful)
Everyone in the Slashdot community seems so worried about the Microsoft monoculture, and yet here we are pushing linux into every possible niche. It can't be optimal to have the same OS running on both our calculators and our supercomputers.
Re:this needs linux? (Score:3, Interesting)
I surely wouldn't buy an expensive calculator that runs out of batteries much faster than my PDA, but I'm glad that people are doing research in that area and maybe improve the system so it becomes easier on the hardware and cheaper; just as I think it's a good thing
RPN is cool for more than engineering (Score:3, Interesting)
During "Y2K", we had to do lots of testing of interest accruals, and it was a lifesaver.
LONG LIVE RPN.
Will it replace my HP 16C (Score:2)
If it's a PDA/Calculator hybrid with a touch screen, forget it! I don't want to have to choose between greasy fingerprints or always fumbling for a stylus.
The past RPN of (Score:4, Informative)
Reverse Polish notation was invented by an Australian [liv.ac.uk] in response to Polish notation, which was invented (gasp!) by a Pole [calculator.org].
The whole story here is [calculator.org]
HP-48C and HP-16 (?) (Score:2)
One of the actuarials asked me to borrow it.
Sure I said, but it uses RPN.
What is RPN? she asked.
Reverse Polish Notation - I've answered.
She looked at me VERY SUSPICIOSLY.
Is this somd kind of polish joke? -- she said.
(beautiful girl, by the way. and actuarial)
The past and future of RPN (Score:3, Interesting)
The tremendous success of the HP-12C in business is proof enough. And ask any HP-41 user how he likes his machine. The thing is a tool that helps you get a job done in as few steps as possible.
I use a 48GX or 49g+ every day. I much prefer the 48GX keyboard and the location of the Enter key (although I'm slowly getting used to that), but everything else about the 49g+ is better: much faster, much better and slightly larger display, and lots more 'stuff'.
Unlike some people I don't mind the 48/49 implementation of RPN (actually RPL) compared with the old style 4-level stack, but a lot of old timers refuse to use the RPL machines that started with the 28. At the same time I still like the 41/42 a lot. There's surely a place for machines like the 32S II. It remains to be seen how the 33S with its odd looking keyboard does in the marketplace.
I'm one of a very few who have an HP PDA based on Linux that never made it to production. Display contrast isn't very good, but otherwise it's decent but not feature laden because the project got killed and people lost their jobs. For this reason it's heartening that someone's talking about doing an HP handheld running Linux, and I'll support their efforts any way I can. It's about time for the user community to pitch in - this reminds me of the PPC 44 project talked about what, 20 years ago?
My first introduction to RPN came during the ACT (Score:3, Funny)
The future of RPN is in the past (Score:4, Insightful)
Re:TI Rocks (Score:5, Insightful)
Re:TI Rocks (Score:2)
Re:TI Rocks (Score:2, Informative)
Re:TI Rocks (Score:2)
Re:My survey response (Score:4, Interesting)
Re:My survey response (Score:5, Funny)
The modern calculator should be able to handle easy RGB triplet to hex conversion, as well as IP xxx.xxx.xxx.xxx 'Bruce' format (I can't remember what that format is called, so I just refer to it as Bruce to save confusion) to 32-bit format.
Oh yeah, and a built-in function for calculating the air speed velocity of laden and unladen African and European swallows, based on various factors such as wind speed, elevation (density of air, ya know), age & weight of birds and any burden they may be carrying. Granted, even with that, it won't be all THAT accurate, but it's better than clacking two coconuts together
Oh, it should also have built-in 802.11g WiFi & IEEE1394.b.
And If I can use it to control the TV remotely, that'd be great, thanks.
I still prefer the physical format of my trusty HP11C, but then again, I don't need graphing ability in my calculator. Graphing's for nerds.
Re:My survey response (Score:2)
Bruce's real name (Score:2)
They Call Me ... Bruce! (Score:3, Funny)
Another good feature of the calc would be to enter either an RGB triplet or a hex colour code and have it find the nearest web-safe palette colours (on either side). That'd be just dandy.
And built-in unit conversions wouldn't hurt. Volkswagens to other volumetric measurements, football fields to meters, and whatnot. And hogsheads, don't forget the hogsheads! And 'stones,' so we can figure out how much Bridget Jones weighs in the upcoming sequel.
And h
Re:My survey response (Score:3, Interesting)
I was addicted after using it for, oh, a month. It took some getting used to, though. Unfortunately, I didn't realize I liked it until the calculator (HP 48g+) was stolen. I pity the poor sap here on campus who buys it from whoever stole it, but isn't able to use it.
Re:My survey response (Score:5, Funny)
- hey, can you lend me your calculator?
- no, you won't know how to use it.
- yes I will.
- ok, if you really want.
- [1] [+]: + Error: Too Few Arguments hey it's not working!
- I told you...
Re:My survey response (Score:5, Insightful)
Seriously, why are we worried about the "future" of inconvenient input formats?
How is RPN inconvenient? Sure, it requires a change of thinking initially, but the gains are traditionally a lot more than the initial effort required. Even just in my limited use of RPN in a college environment, I have seen the benefits as far as speed and yes, convenience.
In one of my recent math classes, the instructor spent 20 minutes helping people to enter a semi-complex formula with parenthetical notation. With RPN, I didn't have to deal with messy parenthesis, I just got the work done. As an added bonus, I got to spend those 20 minutes practicing my written Chinese. :)
Re:My survey response (Score:2)
I didn't think anything could shame my 48GX...
Re:My survey response (Score:5, Insightful)
Just starting at the left and working your way to the right, all the while keeping track of parentheses is NOT intuitive. It's just familiar.
Re:My survey response (Score:2)
versus RPN is that:
1. The calculator does the parsing, not you.
2. When you verify formula transcription from what
is printed on paper (vs. what is on the screen of
you calculator) it IS intuitive to compare character
for character left to right, just as you read.
In practice we will hopefully evolve to where the
calculator does pretty formatting of the formula
(a la Mathematica), presents it to you to verify
that it is correct, then calculate.
It would also be nice
Re:My survey response (Score:2)
calculator does pretty formatting of the formula
(a la Mathematica), presents it to you to verify
that it is correct, then calculate.
I had a sharp 9300 [cdecas.free.fr] in highschool, it did that, it was nice...
Then I switched to an HP48gx and I never looked back...
Re:My survey response (Score:2)
http://www.dynamism.com/x505/specs.sh t ml
Quadruple RAM, throw away HDD and replace with a few
Gigs of flash, throw away all connectors besides one
USB 2.0 port and make it thinner and lighter. Also
get rid of color screen.
For me the distinction between a notebook and a
calculator is weight and battery life. If you can
take the above and make it weight less than half a
pound with a week of battery life I'd buy it as a
calculator.
Re:My survey response (Score:3, Interesting)
Having to reenter a large formula just to change a constant is a pain with RPN. Once you get into that Mathematica/Maple working mode where you edit expressions I think algebraic wins.
I have an HP48SX and HP48GX which I like but never use -- I use a great command line program called "calc" in Linux. If I don't have calc I use bc. Both have readline su
Re:My survey response (Score:4, Informative)
That's why you should use variables on the HP48 for that kind of thing...
In school in electrical engineering, I had a huge set of formulas and constants stored in a directory on my HP48GX, all I had to do was to change a constant, then push the right formular onto the stack, press ->NUM once, and had my numeric result (even complex numbers) there, which would have taken at least two sheets of paper by hand.
Re:My survey response (Score:2, Insightful)
RPN is NOT inconvenient if you get used to it.
I actually prefer RPN.
Re:12 C replacement (Score:3, Informative)
Re:12 C replacement (Score:2)
Re:12 C replacement (Score:2)
An HP-12C! After 23 years, they're still in production. Go down to your local office supply megastore and buy one.
I recommend against the newer "12C Platinum". Get the standard model.
Re:12 C replacement (Score:3, Interesting)
And more bugs, too. For instance, when the program is longer than 260 lines, many GTO instructions that should be valid give an error 4. So the extra program memory isn't all that useful, unless you're writing mostly straight-line code. See the November/December 2003 issue of Datafile (the HPCC club magazine) for a list of more HP 12C Platinum bugs, most of which admittedly not as serious as the GTO problem.
Hewlett-Packard used t
Re:This is very good for the student (Score:5, Informative)
Here in the UK, they're forbidden in exams (up to and including university level) and frowned upon as a distraction and hindrance to being able to visual graphs yourself.
Re:What's wrong with just being a calculator? (Score:3, Interesting)
Re:Very great and all... (Score:2, Informative)
Re:RPN Only? (Score:2)