Bye bye Prime

08282014, 05:48 PM
Post: #21




RE: Bye bye Prime
(08282014 05:44 PM)Joe Horn Wrote:(08272014 11:42 AM)walter b Wrote: Well, basically RPN features a finite stack, RPL an infinite stack. KISS. I'm curious, what happens when you try to enter the 129th item? I'm sure you checked, and my Prime is not with me. Bob Prosperi 

08282014, 05:54 PM
Post: #22




RE: Bye bye Prime
(08272014 06:11 PM)sol740 Wrote: I'm considering buying a Prime  is it really as bad as people are saying here?Have a look at: http://www.tricider.com/brainstorming/2eKfifdjarx 

08282014, 07:13 PM
(This post was last modified: 08282014 07:23 PM by Joe Horn.)
Post: #23




RE: Bye bye Prime
(08282014 05:48 PM)rprosperi Wrote:(08282014 05:44 PM)Joe Horn Wrote: ...Prime's RPN stack is 128 levels high, no more, regardless of amount of memory available. Same as traditional RPN: the top level gets pushed off the top of the stack and is lost. However, unlike traditional RPN, Prime's top level does not automatically replicate. EDIT: By the way, this limit of 128 levels is not an RPNonly limitation in Prime. ALL THREE of Prime's history stacks are 128 elements high, but in CAS and Home (Textbook or Algebraic entry modes) those 128 elements include both the inputs and the outputs, whereas in RPN it only includes the outputs. When there are a total of 128 things on ANY history stack (RPN, Textbook/Algebraic, or CAS), putting something new on the bottom of the history stack pushes the top element off that stack and loses it. <0ɸ0> Joe 

08282014, 08:55 PM
(This post was last modified: 08282014 09:01 PM by walter b.)
Post: #24




RE: Bye bye Prime
(08282014 05:44 PM)Joe Horn Wrote:(08272014 11:42 AM)walter b Wrote: Well, basically RPN features a finite stack, RPL an infinite stack. KISS. Thanks for that information  I didn't know that before. I thought of Wickes' RPL. Seems my definition was too simple then. Would "RPN features a finite stack with top level repetition and roll" be better to differentiate between RPN and RPL? d:) 

08282014, 10:05 PM
Post: #25




RE: Bye bye Prime
(08282014 08:55 PM)walter b Wrote:(08282014 05:44 PM)Joe Horn Wrote: If that's the defining difference, then the HP Prime is an RPN machine, not an RPL machine, because Prime's RPN stack is 128 levels high, no more, regardless of amount of memory available. ;) I always thought the principle difference between RPN and RPL machines was in the programming: RPN machines (65, 12c, 32sii) used easytounderstand keystroke programming while RPL machines (48, 49) used those weird commands like <dup> <dup> and so on, which I never took the time to learn although I admit it seems to be a powerful system. 

08282014, 10:42 PM
Post: #26




RE: Bye bye Prime
(08282014 08:55 PM)walter b Wrote: Would "RPN features a finite stack with top level repetition and roll" be better to differentiate between RPN and RPL? <opinion> RPN and RPL are not mutually exclusive concepts. RPL is a Language that uses RPN Notation, just as FOCAL is a Language that uses RPN Notation. One universally recognized hallmark of RPN is adding 2 plus 3 to get 5 by executing 2 3 +. Both the HP41 and the HP 50g do this, so they are both RPN machines according to that hallmark. The user interface is different, sure, but the Reverse Polish Notation is the same, so they are both RPN. RPN is not a user interface; it is a mathematical notation. RPN can be (and has been) implemented in many different user interfaces. Many names have been proposed for these various implementations of RPN, but I don't think HP ever adopted any of those names officially, and none of them have really "stuck" in the user community. Until that happens, awkward things like "Xentry RPN" and "commandline 4level RPN" and "infinitestack RPN" and "Prime RPN" will need to be spelled out to avoid ambiguity. We really, really, really need permanent, unambiguous, universally adopted NAMES for all these various RPN's. And PLEASE don't entertain the idea that any one of them is TRUE RPN. They ALL are "true RPN". Why? Because if you do 2 3 + to get 5, it's truly Reverse Polish Notation, so it's true RPN. The rest is details... details which hopefully some day can be clearly represented by meaningful, unambiguous, nonjudgmental names for their respective RPN implementations. </opinion> <0ɸ0> Joe 

08282014, 11:27 PM
Post: #27




RE: Bye bye Prime
(08282014 10:42 PM)Joe Horn Wrote: ...represented by meaningful, unambiguous, nonjudgmental names for their respective RPN implementations. Oh, that's easy. Oh wait; meaningful, unambiguous and nonjudgemental? No it's not easy, it's not even hard, it's all but impossible to meet those criteria, which I agree are excellent goals. Which of course is why these names have never emerged, despite 30+ years of real smart folks trying to make them. It seems in everyday usage here on the MoHPC Forums, most folks know what one means pretty accurately when one uses "RPL" (it's either 'that powerful language and programing model used on the 48/49/50 that I love' or 'that powerful language and progrmaming model used on the 48/49/50 that I hate'), but the confusion is rampant when one uses "RPN" as it implies most of HP's machines, as several folks have noted here. I never thought about this way before, but Walter may have captured the essence of what is 'classic' RPN by adding 'top level replication and roll'. To me personally, that meets your 3 criteria, but impossible to speak for everyone on that point. And this is my point. Interesting new views on an old topic!! Thanks for that gents. Bob Prosperi 

08292014, 04:18 AM
Post: #28




RE: Bye bye Prime
(08282014 11:27 PM)rprosperi Wrote: I never thought about this way before, but Walter may have captured the essence of what is 'classic' RPN by adding 'top level replication and roll'. Unfortunately, even that phrase is ambiguous; it doesn't distinguish between Xentry RPN and some recent 4level entry line RPN models which also have top level replication and roll, e.g. the HP 20b and 30b in RPN mode. For example, in classic RPN, 1 ENTER 2 ENTER + yields 4, but it yields 3 on the HP 20b and 30b. Also, on the 20b and 30b, Clear stack, 5 ENTER CE (clear entry) 6 ENTER results in 0, 0, 0, 6 on the stack, whereas in classic RPN you'd get 0, 5, 6, 6. Huge difference. But they both have top level replication and roll. So that's not a defining difference. <0ɸ0> Joe 

08292014, 05:55 AM
(This post was last modified: 08292014 05:55 AM by eried.)
Post: #29




RE: Bye bye Prime
(08282014 05:44 PM)Joe Horn Wrote: because Prime's RPN stack is 128 levels high So the Prime is \[(RPN)^{3.5}\] My website: erwin.ried.cl 

08292014, 06:55 AM
Post: #30




RE: Bye bye Prime
(08282014 10:05 PM)Don Shepherd Wrote: RPN machines (65, 12c, 32sii) used easytounderstand keystroke programming while RPL machines (48, 49) used those weird commands like <dup> <dup> and so on, which I never took the time to learn although I admit it seems to be a powerful system. I concur, though that seems a necessary but not sufficient condition. d:) 

08292014, 07:08 AM
(This post was last modified: 08292014 07:17 AM by walter b.)
Post: #31




RE: Bye bye Prime
Ok, let's try to structure the mess a bit (just by heart, I don't have any machine at hand right now):
d:) 

08292014, 08:08 AM
Post: #32




RE: Bye bye Prime
For me, RPL is equivalent to a graphical screen showing several stack lines and with the capacity to put in those lines numbers, variables, programs, etc., altogether. I know that RPL is more related to the programming language but I identify a RPL machine with the other posibilities I have mentioned.
RPN calculators are more related to 1 or 2 screen lines with a limited stack and without the mixture of objects in the stack, at leas not as explicit as with RPL. Of course the programming method is also different. I really prefer RPL calcs because of the "side effects" (bigger screen, memory, stack, etc.) coming with it. 

08292014, 09:24 AM
(This post was last modified: 08292014 09:44 AM by walter b.)
Post: #33




RE: Bye bye Prime
BTW, that definition / categorization is independent of the physical size and shape of the device under investigation. E.g. with the 43S, you'll get RPN on a multiline display.
And there is a test case to find out what you have (kudos to hansklav): 1 ENTER 2 ENTER 3 ENTER 4 ENTER 5 ENTER 6 ENTER 7 ENTER 8 ENTER 9 ENTER + + + + + + + + (8 times) Now, if you get


08292014, 01:13 PM
Post: #34




RE: Bye bye Prime
Perhaps an unambiguous term for the input method is just "postfix input". That covers all variations of RPN, RPL, and everything in between.


08292014, 01:17 PM
Post: #35




RE: Bye bye Prime
Hello folks,
for me it seems the thread has changed his contents, it is not longer a thread about a possibly ugly machine (not only in a aesthetic way), but a thread about the meaning of RPL, RPN, NLP and so on... Maybe it would be a good idea to split this thread in two different ones... Greetings peaceglue 

08292014, 01:29 PM
Post: #36




RE: Bye bye Prime
I agree. But who can do it? Also cutting through that messy reply structure?
d:? 

08292014, 07:22 PM
(This post was last modified: 08292014 07:23 PM by René Franquinet.)
Post: #37




RE: Bye bye Prime  
08302014, 12:02 AM
Post: #38




RE: Bye bye Prime
(08282014 10:42 PM)Joe Horn Wrote: (…) We really, really, really need permanent, unambiguous, universally adopted NAMES for all these various RPN's (…) which hopefully some day can be clearly represented by meaningful, unambiguous, nonjudgmental names (…) In my (still not entirely finished) RPN Tutorial in Appendix G on RPN Variants I propose the following scheme: Purely looking at the workings of the stack of RPN calculators (and not at their programming capabilities) a few RPN variants can be discerned. Both the bottom and the top of the stack may vary. A. Bottom of the stack:
Four types of RPN All four possible combinations of the 2 × 2 possibilities of RPN variants actually do exist, although not always in hardware: α. (alpha type) The combination of Classical RPN with a small stack and ‘top copy on pop’ is well known. Besides the 4level stack of all classical HP RPN calculators (all HP RPN calculators except those listed below after β. and γ.) and their emulations there is the 5level stack of the Heathkit OC1401, and the 8level mode of the WP 31S and WP 34S. β. (beta type) All HP RPN graphing calculators (series 28, 48 & 49, the HP 50g and Prime) have Entry RPN and an unlimited or very large stack (128 stack levels in the Prime). γ. (gamma type) The HP 20b and HP 30b have Entry RPN and a 4level stack with ‘top copy on pop’. δ. (delta type) The Calculator application in Mac OS X in RPNmode combines Classical RPN behaviour of the ENTER key with an unlimited stack. Discussion Following Richard Nelson in his article in HP Solve (#27 p. 42) ‘RPN Evolves’ the terms Classical RPN and Entry RPN only refer to the differences at the bottom of the stack. I think Classical RPN is better here than Classic RPN because the latter term denotes a judgement (‘of the highest quality and outstanding of its kind’) whereas Classical RPN is purely descriptive, as in ‘classical music’ (formal music adhering to certain stylistic principles of the late 18th century). This scheme is unambiguous and nonjudgemental, and can be used for future implementations with different programming languages because it does not say anything about programming capabilities. And it conveys some meaning because it indicates the chronology and link to HP of the RPN variants, α type being the oldest, β type younger and γ type the youngest RPN variant first implemented by HP; and δ type another, nonHP type. The 3level RPN of the HP series 9100 en 9800 could be called ‘preα type’. Just my two cents. Hans 

08302014, 12:22 AM
(This post was last modified: 08302014 11:28 AM by Didier Lachieze.)
Post: #39




RE: Bye bye Prime
(08292014 09:24 AM)walter b Wrote: And there is a test case to find out what you have (kudos to hansklav): There are a few other RPN flavors. For example, if you get
Edited to fix the result for the HP 9100 & 9810. Edited again to revert to the original number for the HP 9100. 

08302014, 12:52 AM
Post: #40




RE: Bye bye Prime
(08302014 12:22 AM)Didier Lachieze Wrote:(08292014 09:24 AM)walter b Wrote: And there is a test case to find out what you have (kudos to hansklav): I don’t have access to an early HP desktop calculator, but judging from the manual I would expect one of the HP 9100 or 9800 series to produce 72 in this test. Who can do the test on the hardware? Hans 

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