HP Forum Archive 20

[ Return to Index | Top of Index ]

What would you prefer: RPN or RPL? Message #1 Posted by Hugh Evans on 20 Oct 2011, 3:18 p.m. Full disclosure: This is for some decision making related to OpenRPN. The reason I have posed this question is that I'm curious if there's much real interest in a RPL based calculator. While it may not be perfect in every way, the 50g is a reasonable option for anyone needing a graphing calculator that has RPL program-ability. When I need a CAS I use a computer, and the same is true for most function plotting, running statistics on huge data sets, etc. From a personal standpoint my dream machine is what the 42s could have been if engineers weren't forced to hold back to prevent it from cannibalizing 48g sales. One loosely proposed concept has been brought up under the title of RPN+ and serves the purpose of an extended version of what we already know. User definable or otherwise unlimited stack would be included. After the core functions are implemented, all others could be written in a scripting language (options such as python and lua have been mentioned.) The other option is *fix, which is effectively sysRPL Forth. If you have some other idea, please put post it. Input is needed so we can feel more confident in our choice of direction.

Re: What would you prefer: RPN or RPL? Message #2 Posted by Massimo Gnerucci (Italy) on 20 Oct 2011, 3:21 p.m., in response to message #1 by Hugh Evans RPN | RPN+

Re: What would you prefer: RPN or RPL? Message #3 Posted by Steve Simpkin on 20 Oct 2011, 3:39 p.m., in response to message #2 by Massimo Gnerucci (Italy) I vote for RPN | RPN+ too. I use a RPL machine (HP-48SX) for my work calculator, but I would rather have an expanded RPN+ for a new calculator.

NNNNNNNNNNNNNNNNNNNNNNNNNN (n.t.) Message #4 Posted by Maximilian Hohmann on 20 Oct 2011, 3:24 p.m., in response to message #1 by Hugh Evans n.t.= No Text

Re: What would you prefer: RPN or RPL? Message #5 Posted by Crawl on 20 Oct 2011, 3:26 p.m., in response to message #1 by Hugh Evans I don't know about RPN / RPL, but I think I'm losing interest in getting any more calculators without a CAS. If a CAS implies RPL, then I'm in the RPL camp.

Re: What would you prefer: RPN or RPL? Message #6 Posted by Gilles Carpentier on 20 Oct 2011, 3:36 p.m., in response to message #1 by Hugh Evans RPL forever :D And HP50G specially.

Re: What would you prefer: RPN or RPL? Message #7 Posted by Jeff Johnson on 20 Oct 2011, 3:40 p.m., in response to message #1 by Hugh Evans I'm hardly a programmer any more, but I would hate to see the richness and depth of RPL lost when building an "ultimate" calculator that is to rise above the 50g. RPL is iconic in HP history. If sysRPL FORTH is truly implemented in the classical tradition of the FORTH language, where you build new objects as a combination of existing objects, it would certainly be a powerful way to build and share libraries. That would be a positive vote for *fix.

Re: What would you prefer: RPN or RPL? Message #8 Posted by Hugh Evans on 20 Oct 2011, 4:09 p.m., in response to message #7 by Jeff Johnson Everything we have considered thus far includes FORTH like ability to build commands from a core command set. No matter what, it will be possible to very easily make this hardware into any type of calculator you want. If people just want RPL, it seems that emulating saturn would be the easier route. Commands will not even be limited by the system we implement as other executables can be written.

Re: What would you prefer: RPN or RPL? Message #9 Posted by Donald Williams on 20 Oct 2011, 3:50 p.m., in response to message #1 by Hugh Evans RPN only. Take it one step at a time. If an RPN approach is ever accomplished then do RPL & Forth for those fanatics that need it.

Re: What would you prefer: RPN or RPL? Message #10 Posted by Oliver Unter Ecker on 20 Oct 2011, 3:50 p.m., in response to message #1 by Hugh Evans For your project, make the HW capable enough so it can be both: RPN+ and RPL+. If you can, give it WiFi for really convenient sharing abilities and more. CAS. A calc without multiple visible lines and visible data types such as arrays and infix expressions, isn't really a suitable base, I think. So, I'd say, yes, you need an RPL-style machine if you want to offer a CAS. I'm currently implementing a CAS for my project, ND1. It's effectively Mathematica, via use of the WolframAlpha API. How cool are Mathematica results in an RPL calc? Very... As I mention in your project's forum, if you make this machine a suitable base, I'll work on making ND1 available for it. If you add WiFi, it will have a Mathematica-based CAS. [EDIT: To clarify, I'm suggesting a system that's open enough to "boot" into multiple calculators. I added more thoughts to the thread in the openrpn forum.] Edited: 20 Oct 2011, 4:02 p.m.

Re: What would you prefer: RPN or RPL? Message #11 Posted by Marcus von Cube, Germany on 20 Oct 2011, 5:32 p.m., in response to message #10 by Oliver Unter Ecker Quote: If you can, give it WiFi for really convenient sharing abilities and more. For a device like this, Bluetooth would be the better choice: easy peer-to-peer networking and low power consumption.

Re: What would you prefer: RPN or RPL? Message #12 Posted by Jim Yohe on 20 Oct 2011, 4:03 p.m., in response to message #1 by Hugh Evans RPN

Re: What would you prefer: RPN or RPL? Message #13 Posted by Han on 20 Oct 2011, 4:03 p.m., in response to message #1 by Hugh Evans I guess I'm not seeing much of a difference in RPN vs RPL. I sort of see RPN as just the keystroke version of RPL (and hence a bit more limited). In fact, on the HP48 and similar systems, if you wanted to do keystroke programming, it could be done provided you start with << and end with >> -- everything in between may as well be keystrokes. The only other minor difference is how ENTER is implemented.

Re: What would you prefer: RPN or RPL? Message #14 Posted by Marcus von Cube, Germany on 20 Oct 2011, 5:33 p.m., in response to message #13 by Han Quote: The only other minor difference is how ENTER is implemented. And STO...

Re: What would you prefer: RPN or RPL? Message #15 Posted by Crawl on 20 Oct 2011, 6:13 p.m., in response to message #14 by Marcus von Cube, Germany And GOTO. (I do wish RPL had GOTO) Edited: 20 Oct 2011, 6:13 p.m.

Re: What would you prefer: RPN or RPL? Message #16 Posted by Eddie W. Shore on 21 Oct 2011, 12:21 a.m., in response to message #15 by Crawl Quote: And GOTO. (I do wish RPL had GOTO) So do I - and LBL. My biggest pet peeve with RPL is the lack of GTO and LBL.

Re: What would you prefer: RPN or RPL? Message #17 Posted by Thomas Radtke on 21 Oct 2011, 4:13 a.m., in response to message #16 by Eddie W. Shore Give me a BREAK!

Re: What would you prefer: RPN or RPL? Message #18 Posted by Maximilian Hohmann on 21 Oct 2011, 4:45 a.m., in response to message #17 by Thomas Radtke Quote: Give me a BREAK! And a PAUSE (but the kind that accepts keystrokes while pausing, otherwise we cannot play Lunar Rocket Lander properly)

Re: What would you prefer: RPN or RPL? Message #19 Posted by Thomas Radtke on 21 Oct 2011, 5:17 a.m., in response to message #18 by Maximilian Hohmann Which, of course, is first priority ;-).

Re: And a short manual please! Message #20 Posted by Maximilian Hohmann on 21 Oct 2011, 7:43 a.m., in response to message #19 by Thomas Radtke Quote: Which, of course, is first priority ;-). Yes! And second priority is a short and simple manual for me. I'm spoilt by 20+ years of Macintosh usage and really don't want to waste my time with anything that can not be mastered intuitively. Ten pages maximum for the manual (8 of which the list of functions :-) , not more than two for using and programming) and I buy it!

Re: And a short manual please! Message #21 Posted by John B. Smitherman on 21 Oct 2011, 8:22 a.m., in response to message #20 by Maximilian Hohmann Hi Maximilian. To me the Mac user interface isn't intuitive but rather it's consistent. It works the same way from software app to software app year after year. For example, dragging a disc to the trash can to eject it isn't intuitive at all but it's worked that way for many years. John

Re: And a short manual please! Message #22 Posted by Oliver Unter Ecker on 21 Oct 2011, 9:39 a.m., in response to message #20 by Maximilian Hohmann How much shorter than this RPL on wikipedia do you want the manual to be? Honestly, I don't understand why people say that RPL has a steep learning curve. The language is about as easy as it gets. Mastering the 700+ commands in a 50g (or other RPL machine) is another matter, but you don't need any of them to comprehend, and use, the language. The command set isn't there to intimidate, either. It's there for you to pick up something when you need it, and save you from wasting time on reinventing the wheel.

Re: And a short manual please! Message #23 Posted by M. Joury on 21 Oct 2011, 12:04 p.m., in response to message #22 by Oliver Unter Ecker I don't think that it is difficult so much as different. From my perspective, coming at it as a programmer, it is a relatively easy language with a lot of power. Many people seem to miss that it *is* keystroke programmable (just place your keystrokes between <<>> and you are set). Maybe the looping constructs are more involved but with that added complexity comes power. And they really are not that hard to master. However, I would still rather have FOCAL or RPN for quick and dirty solutions and RPL for more involved, fully developed, applications. Cheers, -Marwan

Re: And a short manual please! Message #24 Posted by Eddie W. Shore on 21 Oct 2011, 3:35 p.m., in response to message #22 by Oliver Unter Ecker The Wikipedia article does a great job of summarizing the main commands on RPL. Also check out my RPL blogs on Eddie's Math and Calculator Blog for a summary of some of the main commands.

Re: What would you prefer: RPN or RPL? Message #25 Posted by Han on 21 Oct 2011, 3:10 p.m., in response to message #18 by Maximilian Hohmann You can do all that with RPL. You can also have temporary variables that span across multiple subroutines (i.e. temporary global variables) by prefixing them with the left arrow (e.g. <-p) Quote: << << subprg1 >> << subprg2 >> ... << subprgn >> -> s1 s2 ... sn << @ main routine goes here @ call a subroutine with: s1 EVAL @ do a GOTO with: s1 KILL @ pause and wait for keypress with: 0 WAIT >> >> I'm not familiar with how BREAK works in RPN... does that just exit the current loop? Or does it kill the program?

Re: What would you prefer: RPN or RPL? Message #26 Posted by Eddie W. Shore on 21 Oct 2011, 3:37 p.m., in response to message #25 by Han Cool - up to now I had to store the subroutines as global variables and purge them in the end. I have to try this! Thanks!

Re: What would you prefer: RPN or RPL? Message #27 Posted by Marcus von Cube, Germany on 21 Oct 2011, 4:52 p.m., in response to message #25 by Han No need for BREAK in RPN, a GTO just does the job nicely. Cleanup of loops is just by reusing their counter register(s). BREAK would be a nice addition to RPL because it lacks a clean way to exit a loop early if some condition becomes true. This is common practice in languages like C or Java.

Re: What would you prefer: RPN or RPL? Message #28 Posted by Paul Berger (Canada) on 21 Oct 2011, 7:19 p.m., in response to message #27 by Marcus von Cube, Germany I made a clean exit from a FOR NEXT loop by bumping up the loop counter to the exit value when I determined there was no point continuing the loop.

Re: What would you prefer: RPN or RPL? Message #29 Posted by Marcus von Cube, Germany on 22 Oct 2011, 4:54 a.m., in response to message #28 by Paul Berger (Canada) Isn't the loop index precomputed and immune against later modifications in RPL? What about a loop without an index variable?

Re: What would you prefer: RPN or RPL? Message #30 Posted by Paul Berger (Canada) on 22 Oct 2011, 3:01 p.m., in response to message #29 by Marcus von Cube, Germany From the AUR Quote: FOR takes xstart and xfinish as the beginning and ending values for the loop counter, then creates the local variable counter as a loop counter. Then, the loop clause is executed; counter can be referenced or have its value changed within the loop clause. NEXT increments counter by one, and then tests whether counter is less than or equal to xfinish. If so, the loop clause is repeated (with the new value of counter). By loops with out an index do you mean 'while' and 'do until' loops? in both of these cases these loops execute until some logical condition meets the exit criteria. While I have not explicitly tried this in RPL I would expect you should be able to have a compound test and one of the terms can be an exit flag that you could set or clear when you determine that you wish to exit the loop early.

Re: What would you prefer: RPN or RPL? Message #31 Posted by Marcus von Cube, Germany on 22 Oct 2011, 4:12 p.m., in response to message #30 by Paul Berger (Canada) I stand corrected, RPL allows the modification of the loop counter and the increment can be taken from stack each time. There is a loop construct with no visible counter in RPL (START/NEXT). But there is also a variant with a variable increment. All these loops (except START/NEXT) can be exited early by modification of the increment or the loop counter but you still need an IF block to skip any unwanted statements in the block. BREAK would make things easier.

Re: What would you prefer: RPN or RPL? Message #32 Posted by Paul Berger (Canada) on 22 Oct 2011, 5:19 p.m., in response to message #31 by Marcus von Cube, Germany Yes but even for break you need to make some kind of decision to get to the break in my case I did the test to see if it was worth continuing and all the code for the loop was under the THEN term and under the ELSE term I bumped up the loop count for early exit. I don't see how a BREAK command would make that any better.

Re: What would you prefer: RPN or RPL? Message #33 Posted by Thomas Radtke on 23 Oct 2011, 4:59 a.m., in response to message #32 by Paul Berger (Canada) A break is convenient to immediately leave a loop w/o enclosing the remaining code in a conditional statement, as it would be necessary when bumping the counter. Of course, one can live without BREAK, but it gives more clearly arranged code when using it. Java is quite stripped down compared to C++ in some respect but contains everything one needs. It's remarkable that break has been left in and that it's widely used.

Re: What would you prefer: RPN or RPL? Message #34 Posted by Marcus von Cube, Germany on 23 Oct 2011, 8:34 a.m., in response to message #33 by Thomas Radtke In Java, break has even been extended to take a label. This way you can break out several loops at once which is otherwise a mess. The labeled break isn't a goto, you can just 'name' the loop to break.

Re: What would you prefer: RPN or RPL? Message #35 Posted by fhub on 23 Oct 2011, 8:49 a.m., in response to message #34 by Marcus von Cube, Germany Quote: In Java, break has even been extended to take a label. This way you can break out several loops at once which is otherwise a mess. I still remember the good old BASIC times ;-) where you could simply go FROM wherever you want TO wherever you want with a GOTO! Ok, many called this "Spaghetti code", but nevertheless this was quite comfortable (and BTW, every assembly code works exactly the same way) ... :-) Franz

Re: What would you prefer: RPN or RPL? Message #36 Posted by Marcus von Cube, Germany on 23 Oct 2011, 10:10 a.m., in response to message #35 by fhub Leaving a FOR/NEXT loop this way leaves an open control structure in memory. :-(

Re: What would you prefer: RPN or RPL? Message #37 Posted by fhub on 23 Oct 2011, 10:40 a.m., in response to message #36 by Marcus von Cube, Germany Quote: Leaving a FOR/NEXT loop this way leaves an open control structure in memory. :-( Well, first I don't think this would be a problem at all (you'll certainly not do it thousands of times ;-)), and then you could always set the loop-variable to the endvalue and GOTO the NEXT statement.

Re: What would you prefer: RPN or RPL? Message #38 Posted by Oliver Unter Ecker on 22 Oct 2011, 5:46 a.m., in response to message #28 by Paul Berger (Canada) Plus, don't you still have to put an IF around the following code, until the NEXT/STEP? 'fraid there's no substitute to BREAK.

Re: What would you prefer: RPN or RPL? Message #39 Posted by Paul Berger (Canada) on 22 Oct 2011, 3:07 p.m., in response to message #38 by Oliver Unter Ecker Yes you do but it would seem to me that in order to determine if you should exit from a loop early, you would need to make some kind of a decision within the loop. I just don't think the lack of BREAK is such a big deal.

Re: What would you prefer: RPN or RPL? Message #40 Posted by Oliver Unter Ecker on 23 Oct 2011, 1:27 a.m., in response to message #39 by Paul Berger (Canada) Consider for i:=0 to 1000 if condition break if condition2 ... endloop Yes, you can rewrite this to for i:=0 to 1000 if condition i:=1000 if i < 1000 && condition2 ... endloop but you have to have knowledge of the end value and you need to insert one additional IF, or condition for an existing IF, per break. It looks bad and it introduces extra computation. What's more, if the end value should change, you have to maintain your end value update and code exclude IFs, or your code will (spuriously) fail. This wouldn't be so bad, if breaks were rare. But running over a domain, checking for something, and doing an early exit is the life-blood of basic search algorithms, and happens all the time. The RPL designers tried to keep things simple, and in this case maybe a little too simple. CONTINUE is missing too...

Re: What would you prefer: RPN or RPL? Message #41 Posted by Crawl on 21 Oct 2011, 6:09 p.m., in response to message #25 by Han KILL will kill everything that's running; if a parent program calls a subprogram that has KILL in it, both programs are killed. People have pointed out that a language can be turing complete without GOTO, which is true; in principle, you could just be very careful about your structures. However, we are talking about hand-held calculators here, and I think for that application, it's important to be able to write programs on the fly. I've been in situations where a slight revision to a program would necessitate massive changes to the structure (adding many more IF THEN blocks throughout) when a simple goto or break would have done the job. It is, by the way, possible to do loop breaking with error trapping / custom errors. I think this is the standard way it's done now. I think a built-in BREAK command would be more elegant.

Re: What would you prefer: RPN or RPL? Message #42 Posted by Oliver Unter Ecker on 21 Oct 2011, 7:39 p.m., in response to message #41 by Crawl Agreed. And that's why I (just recently) put it into RPL+. Along with IFTB ("if-then-break") and CONTINUE and IFTC ("if-then-continue").

Re: What would you prefer: RPN or RPL? Message #43 Posted by Eddie W. Shore on 23 Oct 2011, 4:24 p.m., in response to message #25 by Han I tried your suggestion Han but I am having trouble getting the program to execute. An example: The goal of this program is to give a menu of 3 options: return the principal root of a number (F1: RPN), return all the real roots of a number (F2; REAL), and return all the real and complex roots of a number (F3: ALL). << << 'X' PURGE SWAP ^ SWAP - X ZEROS >> -> SUB1 << { { "PRN" << XROOT ->NUM >> } { "REAL" << -103 CF SUB1 EVAL >> } { "ALL" << -103 SF SUB1 EVAL >> } } TMENU >> I get "CF Error: Undefined Local Name" error when I try to run the REAL option. I get "SF Error: Undefined Local Name" error when I try to run the ALL option.

Re: What would you prefer: RPN or RPL? Message #44 Posted by Marcus von Cube, Germany on 23 Oct 2011, 4:41 p.m., in response to message #43 by Eddie W. Shore It looks like the local variable SUB1 is not accessible to the routine tied to the options "REAL" or "ALL". You can try <-SUB1 as the local name. If that doesn't work you need to define a global variable for SUB1. It depends on the inner workings of TMENU. You should create a subdirectory for the variables and the program to avoid cluttering HOME.

Re: What would you prefer: RPN or RPL? Message #45 Posted by Eddie W. Shore on 23 Oct 2011, 6:14 p.m., in response to message #44 by Marcus von Cube, Germany I have been using global variables and purging them at the end: i.e. << <<subroutine goes here>> 'SUB1' STO (Main program) 'SUB1' PURGE >>

Re: What would you prefer: RPN or RPL? Message #46 Posted by Marcus von Cube, Germany on 24 Oct 2011, 2:54 a.m., in response to message #45 by Eddie W. Shore You didn't try the backwards arrow? This introduces a special type of local variable with extended visibility. (Don't ask for details!)

Re: What would you prefer: RPN or RPL? Message #47 Posted by Geir Isene on 20 Oct 2011, 4:07 p.m., in response to message #1 by Hugh Evans RPN every day of the week and twice on Sunday.

Re: What would you prefer: RPN or RPL? Message #48 Posted by Geir Isene on 20 Oct 2011, 6:32 p.m., in response to message #47 by Geir Isene And if you want a scripting language to go with that, try Raven.

Re: What would you prefer: RPN or RPL? Message #49 Posted by bill platt on 20 Oct 2011, 4:12 p.m., in response to message #1 by Hugh Evans Algebraic stack.

Re: What would you prefer: RPN or RPL? Message #50 Posted by Lode on 20 Oct 2011, 4:14 p.m., in response to message #1 by Hugh Evans RPN, but with more than 4 levels.

Re: What would you prefer: RPN or RPL? Message #51 Posted by Andrés C. Rodríguez (Argentina) on 20 Oct 2011, 4:23 p.m., in response to message #1 by Hugh Evans RPN, perhaps with a well designed complex stack. Four-level stack is fine for me, with classic HP behavior.

Re: What would you prefer: RPN or RPL? Message #52 Posted by Ángel Martin on 20 Oct 2011, 4:31 p.m., in response to message #1 by Hugh Evans RPN, please.

Re: What would you prefer: RPN or RPL? Message #53 Posted by David Hayden on 20 Oct 2011, 5:34 p.m., in response to message #1 by Hugh Evans RPL is a very small, very efficient programming environment. The compiler and decompiler are pretty simple, so it's easy to write programs in RPL on the calculator. On the down-side the syntax is not very intuitive. I think many of the design goals for RPL don't really apply any more, so I'd vote for key keystroke programmability of RPN and a more modern scripting language as you mention.

Re: What would you prefer: RPN or RPL? Message #54 Posted by x34 on 23 Oct 2011, 3:34 a.m., in response to message #53 by David Hayden Quote: I think many of the design goals for RPL don't really apply any more I agree. Is not it the reason why HP lost education battle to TI?

Re: What would you prefer: RPN or RPL? Message #55 Posted by Paul Dale on 23 Oct 2011, 3:58 a.m., in response to message #54 by x34 I very much doubt RPL is the reason HP lost the educational market. Cost is a big one. HP was never cheap. RPN is probably the second. When I was at school (early 1980's) the teachers had at most half a clue as to how to calculate in RPN but they really weren't sure. The fight was lost here before I finished high school -- there were only two of us with HP calculators at that stage. Everyone else used CASIO, actually I did too since my 34C was broken & I bought a 602P. A few more at university (late 1980's) used RPN but it was still in the minority. When the 28C came out nothing really changed. - Pauli

Re: What would you prefer: RPN or RPL? Message #56 Posted by Eddie W. Shore on 23 Oct 2011, 4:27 p.m., in response to message #55 by Paul Dale There isn't wide-spread instructional materials of RPN/RPL - not it was promoted as much (I think) compared to algebraic operated calculators.

Re: What would you prefer: RPN or RPL? Message #57 Posted by Software49g on 23 Oct 2011, 4:59 p.m., in response to message #56 by Eddie W. Shore I have several thousands pages of RPL documentation on my laptop, from deep down technical to user level and the internet is full of RPL instructions (and RPN). So what is missing in your opinion ? The real problem is that people/user do not read anymore. Which, as a quid pro quo, leads to declining manuals which are read even less which ... I will be comming out with a help for *all* commands ASAP as shown here HP 50G Full Command and Function Reference incorporated into the O.S. which might be helpful as a short reference *but* for sure it can not overcome a lack of missing fundamentals which is the primary function of books. Regards, Andreas http://www.software49g.gmxhome.de By the way: For years I have been saying that the success of a machine targeting at professionals depends on the documentation/ease of use that comes with it. But of cause that is contradictory to a company looking at short term profit only. Edited: 23 Oct 2011, 5:02 p.m.

Re: What would you prefer: RPN or RPL? Message #58 Posted by David Hayden on 23 Oct 2011, 10:46 p.m., in response to message #55 by Paul Dale I was in high school in the late 70's. Everyone had a calculator, but most people used TI's even then. A few - perhaps 5% - used HP. So what has really changed? I think it's the fact that the TI-83 is basically built into the textbooks now. My daughter, along with everyone else in her class, was required to buy one in 6th grade. The calculators are built into the books, and the lessons, and getting the teachers to change would be a lot of work. I think this is actually one place where HP could very effectively leverage us, the user community. We could create HP-versions of the specific calculator lessons/exercises in specific textbooks. So if a teacher uses textbook XYZ, he or she (or the student) could go to a website and download the HP version of calculator lessons. Now if the teacher says "do the exercise on page 234," the enlightened HP student could just flip to the appropriate "translation" in their handy HP packet.

Re: What would you prefer: RPN or RPL? Message #59 Posted by Michael Kussmaul on 20 Oct 2011, 5:47 p.m., in response to message #1 by Hugh Evans RPL - and please NO CAS :-) I guess there are two domains: Education: They are already gone to algebraic, no one is getting an RPN/RPL calculator - only if he/she is a rebel :-) And there are tons of calculators with CAS for them - because you are not allowed to have a computer on an exam, CAS might be good for them... Grown-Ups: Like me, who need a calculator at work, for light calculations (some cosine here an there, perhaps some small apps for quick calculations in a meeting, etc). For everything I need more than 30sec to enter (that includes 10x10 matrices) I use a computer, as it is faster overall.

Re: What would you prefer: RPN or RPL? Message #60 Posted by Crawl on 20 Oct 2011, 6:18 p.m., in response to message #59 by Michael Kussmaul I assure you that a CAS can be useful to grownups.

Re: What would you prefer: RPN or RPL? Message #61 Posted by Michael Kussmaul on 21 Oct 2011, 4:49 a.m., in response to message #60 by Crawl Yes, I use it all the time - on my computer :-) Of course you are right, I was just a bit exaggerating...

Re: What would you prefer: RPN or RPL? Message #62 Posted by Miguel Toro on 20 Oct 2011, 5:50 p.m., in response to message #1 by Hugh Evans RPN. Thanks, Miguel

Re: What would you prefer: RPN or RPL? Message #63 Posted by DigiGal on 20 Oct 2011, 5:54 p.m., in response to message #1 by Hugh Evans Another vote for RPN

Re: What would you prefer: RPN or RPL? Message #64 Posted by M. Joury on 20 Oct 2011, 5:59 p.m., in response to message #1 by Hugh Evans Both :)? I'll take RPN as my preference.

Re: What would you prefer: RPN or RPL? Message #65 Posted by Tim Wessman on 20 Oct 2011, 6:01 p.m., in response to message #1 by Hugh Evans Is there a neither option? Algebraic is the way to go. TW

Re: What would you prefer: RPN or RPL? Message #66 Posted by Oliver Unter Ecker on 20 Oct 2011, 6:12 p.m., in response to message #65 by Tim Wessman Really?! No advantages to the RPN method of entry? Or you mean just for the user programming language?

Re: What would you prefer: RPN or RPL? Message #67 Posted by Hugh Evans on 20 Oct 2011, 6:12 p.m., in response to message #65 by Tim Wessman Our version of RPL, *fix, is probably the best option for neither. It functions in prefix, infix, and postfix. Here's a link to a java implementation if you want to see it in action: *fix

Re: What would you prefer: RPN or RPL? Message #68 Posted by Howard Owen on 20 Oct 2011, 9:10 p.m., in response to message #65 by Tim Wessman Quote: Algebraic is the way to go. Trolllllllll... :)

Re: What would you prefer: RPN or RPL? Message #69 Posted by Steve Simpkin on 21 Oct 2011, 2:00 p.m., in response to message #65 by Tim Wessman Quote: Is there a neither option? Algebraic is the way to go. What is this "Algebraic" thing that you speak of? I am not familiar with it.

Re: What would you prefer: RPN or RPL? Message #70 Posted by Howard Owen on 21 Oct 2011, 6:52 p.m., in response to message #69 by Steve Simpkin "You keep using that word. I do not think it means what you think it means."

Re: What would you prefer: RPN or RPL? Message #71 Posted by Paul Dale on 22 Oct 2011, 3:19 a.m., in response to message #70 by Howard Owen It comes from a combination and contraction of two words: Algae Braille It refers to an ancient and little used form of written communication that lays out a thick sheet of pond scum and then glues blood sucking leeches into a variety of positions to render the letters. The writing is read by placing your finger tips onto the slimy surface and feeling the leeches bite into you. One has to be wary however, an algebraic rendition of Tolstoy's classic War and Peace is very likely to render the reader unconscious, if not dead, due to blood loss. Additionally, unscrupulous authors have been known to practice bdellotry before affixing the leeches into position, thus causing a greater level of blood loss amongst their readers. Finally, the pond scum is very likely to infect the reader with a variety of nasty bacterial diseases. - Pauli

Re: What would you prefer: RPN or RPL? Message #72 Posted by Walter B on 22 Oct 2011, 4:18 a.m., in response to message #71 by Paul Dale Heh heh, what did you read last?

Re: What would you prefer: RPN or RPL? Message #73 Posted by Paul Dale on 22 Oct 2011, 4:23 a.m., in response to message #72 by Walter B The last book I read was The Stainless Steel Rat Sings the Blues by Harry Harrison. - Pauli

Re: What would you prefer: RPN or RPL? Message #74 Posted by Lyuka on 22 Oct 2011, 6:46 a.m., in response to message #73 by Paul Dale Hi Paul, I thought it would be from The Devil's Dictionary by Ambrose Bierce, and also had consulted the American Heritage Dictionary for its origin, that was also interesting :-) [Arabic, al-, the + jabr, bone-setting, restoration (from jabara, to set (bones), force, restore.)] Lyuka

Re: What would you prefer: RPN or RPL? Message #75 Posted by Paul Dale on 22 Oct 2011, 6:56 a.m., in response to message #74 by Lyuka I wasn't aware of The Devil's Dictionary. Interesting. The real definition is a bit of a surprise. Quite unexpected -- not that it comes from the Arabic but what exactly it does come from. I prefer the one I made up :-) - Pauli

Re: What would you prefer: RPN or RPL? Message #76 Posted by Walter B on 22 Oct 2011, 3:28 p.m., in response to message #75 by Paul Dale Words containing the syllable "al" are suspects having Arabic origin: Gibraltar, Andalusia, Almeria, ...

Re: What would you prefer: RPN or RPL? Message #77 Posted by Howard Owen on 22 Oct 2011, 7:25 p.m., in response to message #76 by Walter B Having fun with the online etymology dictionary. Alcohol, albatross, alcove, alchemy, alembic and algebra all either originated in Arabic or passed through it on the way to English. Alderman, aleatory, aleph, ale, alert, algae and alien are all from sources other than Arabic.

Re: What would you prefer: RPN or RPL? Message #78 Posted by Paul Dale on 22 Oct 2011, 7:40 p.m., in response to message #76 by Walter B I said I wasn't surprised that the word had Arabic origins. I was surprised at the meanings of the words is came from. - Pauli

Re: What would you prefer: RPN or RPL? Message #79 Posted by Oliver Unter Ecker on 22 Oct 2011, 4:23 a.m., in response to message #71 by Paul Dale I always wondered. Thanks for clarifying the issue scientifically.

Re: What would you prefer: RPN or RPL? Message #80 Posted by Patrice on 20 Oct 2011, 7:16 p.m., in response to message #1 by Hugh Evans RPN if OpenRPN is to be a non graphic calc (43S) Patrice

Re: What would you prefer: RPN or RPL? Message #81 Posted by Les Bell on 20 Oct 2011, 7:34 p.m., in response to message #1 by Hugh Evans For a calculator, definitely RPN. It's convenient for back-of-an-envelope calculations and use in meetings, which is what I want a calculator for. Keystroke programmability to automate some repetitive calculations is all I need, and GTO/GSB/ISZ/DSE will get the job done. If the problem is complex enough to require RPL, with its highly regular but awkward syntax, I'd prefer to sit at a computer and work with GNU Octave or R or Matlab or Mathematica. Best, --- Les [http://www.lesbell.com.au]

Whats RPL? Message #82 Posted by Geoff Quickfall on 20 Oct 2011, 8:29 p.m., in response to message #1 by Hugh Evans ;-) RPN

Re: Whats RPL? Message #83 Posted by Thomas Chrapkiewicz on 21 Oct 2011, 7:06 a.m., in response to message #82 by Geoff Quickfall I agree!

Re: What would you prefer: RPN or RPL? Message #84 Posted by Eddie W. Shore on 21 Oct 2011, 12:20 a.m., in response to message #1 by Hugh Evans Good question! I like RPN for simplicity, RPL for the extended set of commands. Truthfully, I'm not sure if I can be on team-RPN or team-RPL yet because I like both. Here's how I would imagine some of the RPL commands on an RPN (keystroke) machine: FOR Loop: start end FOR register# ** commands ** NEXT WHILE Loop: y x WHILE Test# (i.e. #1: x=y; #2: x>y; #3: x<y, etc) ** commands ** WEND DO Loop: DO ** commands ** y x UNTIL Test# (i.e. #1: x=y, #2: x>y, #3: x<y, etc) If text is allowed - it would be handled like the 41C/42S (?): CHOOSE - each option is presented for 2 seconds. ("1. Choice 1", "2. Choice 2", "3. Choice 3"...) - and cycles until something is chosen. Up to 9 options. "text 1" "text 2" ... "text n" CHOOSE PROMPT - message displays for 2 seconds and then stops for input. "text" PROMPT DISP n - message displays for n seconds. "text" or register# DISP n If graphing functions is featured: PLOT - plots an equation as an algebraic object. 'equation' PLOT XRNG and YRNG would work the same way as it would on the graphing calculators. Edited: 21 Oct 2011, 12:22 a.m.

Re: What would you prefer: RPN or RPL? Message #85 Posted by megarat on 21 Oct 2011, 1:34 a.m., in response to message #1 by Hugh Evans Even yet another vote for RPN. Although I do enjoy messing around with RPL from time to time, for what I use calculators for, RPN is the bee's knees.

Re: What would you prefer: RPN or RPL? Message #86 Posted by Bart (UK) on 21 Oct 2011, 3:19 a.m., in response to message #1 by Hugh Evans RPL definitely.

Re: What would you prefer: RPN or RPL? Message #87 Posted by Thomas Radtke on 21 Oct 2011, 4:18 a.m., in response to message #1 by Hugh Evans 42S+27S - RPN w/ full blown equation editor, i.e. a tuned Binford 9100 turbo (or, a 32SIII).

Re: What would you prefer: RPN or RPL? Message #88 Posted by Cristian Arezzini on 21 Oct 2011, 8:20 a.m., in response to message #1 by Hugh Evans RPL for me, any day. I (have to) use RPN often but I just don't like the ENTER behavior and the limited stack, the 48/50 way is so much easier for me. But I like the RPN's STO. Cristian

Re: What would you prefer: RPN or RPL? Message #89 Posted by E Walsh on 21 Oct 2011, 10:14 a.m., in response to message #1 by Hugh Evans RPN please!!

Re: What would you prefer: RPN or RPL? Message #90 Posted by Fred Lusk on 22 Oct 2011, 1:47 a.m., in response to message #1 by Hugh Evans Because I started with my dad's HP-35 (while in junior high school!), RPN is ingrained and natural to me. Most of the programs I still use today for civil engineering, I wrote on an HP-41CX and an HP-42S back in the 1980s and 1990s. I still program, but not nearly as much. I have an HP-48G+ and I have dabbled with PRL programming. There is no question that it is enormously more powerful than RPN, but it's just not natural to me and I find it frustrating. It's also a pain to edit on the machine itself. Thank goodness for HPUserEdit. In the final analysis, I greatly prefer RPN. However, I've had this question for years: when the 48 series was designed, why didn't HP include an RPN mode? It would have provided an excellent upgrade path for HP-41 and HP-42S users. I know some engineers who still use an HP-41 because they don't like the HP-48/-49/-50 series. I still use an HP-42S as my primary machine, though I also keep my HP-48G+ in my briefcase ready for use when needed.

Re: What would you prefer: RPN or RPL? Message #91 Posted by Michael Lopez on 23 Oct 2011, 2:18 a.m., in response to message #90 by Fred Lusk Love RPN & still have 2 HP41s (CV & CX) BUT at the end of the day I've come to realize that RPL is my preference as well. My favourite calculators now are the HP 48GX & HP 50G. Hope this helps. Cheers, Michael

[ Return to Index | Top of Index ]

Go back to the main exhibit hall