HP 50g  How to log and edit RPN expression entry?

01162016, 05:15 AM
(This post was last modified: 01162016 05:41 AM by jimbo1qaz.)
Post: #1




HP 50g  How to log and edit RPN expression entry?
I recently moved from a heavily modded TI84+ (slightly unstable) (BASIC causes brain damage) to an HP 50g (cheapest option available XD ). I've had it for a few months, but never really got familiar in practice. This is my first CAS calculator, but seems rather awkward to use.
Integration is a bit tricky: Symbolic home screen, stepbystep symbolic equation editor, numeric equation editor, what else? Also, definite integrals from the home screen require << a b INTVX PREVAL >> . Is there a way to perform fast homescreen definite integration without first INTVXing? Loading the graphing screen is slower than TI84+ Classic mode. Graphing entry forces you to name all Yvalues. Cancelling a graphing operation takes an entire second. One hard issue I encountered is that the slope field only works from the <F4 2D/3D menu, not the <F1 Y= menu. But these questions are for another time... ## EXPR HISTORY, EDITING The biggest problem I have right now, is that when entering expressions in the RPN home screen, numeric values are not preserved when typing. This makes editing symbolic expressions suboptimal, and numeric expressions completely impossible. On the TI84+, I frequently performed textual equation editing directly from the home screen. Although limited (graph variables) and errorprone (parentheses), it was at least functional. As an analogy, RPN is similar to writing a desktop program by typing code directly into a compiler. You cannot easily undo mistakes along the process, nor can you iterate on the original code after running it. RPN is actually worse, because you can't even see the full expression as it's being written (for numeric values). ## HISTORY I discovered you can perform RPN entry in RPL tags << >> instead, duplicate the expression, then evaluate. However, this requires manual duplication, introducing a source of human error. Also, unit conversions and calculus functions behave differently in RPL (I haven't figured out). Most importantly, you no longer get intermediate values, and the walloftext entry is difficult to read. You can also duplicate expressions using ENTER, then perform operations on the lower copy. Still that's errorprone, and doesn't preserve variables. ## EDITING Is the proper solution to use algebraic (backtick) expressions in RPN mode? (Somehow, RPN singleticks do not support typing 2x for 2*x. Inconvenient.) Algebraic expressions can be constructed and edited in the equation editor. But I find the equation editor to be tedious. Also, they're simplified just like RPN. This only allows editing, and does not directly enable a full history. ## LOGGING Is there any program that collects RPN input into a RPL block, and allows you to recall RPL expressions? or something? Similar to Algebraic? 

01162016, 10:44 PM
Post: #2




RE: HP 50g  How to log and edit RPN expression entry?
Try using << >> to put your expression into a code and save it to a variable, for example:
<< 50 25 + '5 * 3 + 10' + >> 'NN' STO should save the expression between << and >> in variable NN Then you can load it to the stack (with RSHIFT and NN softkey) and evaluate with EVAL or edit by pressing the DOWN key (you can also put EVAL into the code). After evaluating your expression you can also use the UNDO command to edit the expression (and save it with LSHIFT and NN softkey). I hope this answers all your questions. 

01162016, 11:18 PM
(This post was last modified: 01172016 12:21 AM by jimbo1qaz.)
Post: #3




RE: HP 50g  How to log and edit RPN expression entry?
I already explained why that's suboptimal. You need to manually insert RPL tags whenever entering expressions, rather than automatically saving input in a clean fashion, as in Algebraic. Also, it doesn't behave nicely with CAS calculus.


01172016, 12:44 AM
Post: #4




RE: HP 50g  How to log and edit RPN expression entry?
I'm struggling to understand what your problem actually is.
If you want to enter as algebraic, evaluate as algebraic and go back and edit mistakes or changes on an algebraic expression then put the 50G into algebraic mode and you're good to go. If you want to use RPL but still enter algebraics then you need to use single tick quotes in RPL mode. If you want to do calculations in RPL and somehow maintain a history of what was typed so that you can go back and edit it, then that is not possible on the 50G. How would the calculator know when you started a calculation so it would know how far back to let you go? Or would you want it to keep a record all the way back to when you turned it on? If you want to do something else, then I've not understood and a specific example might makes things clearer. 

01172016, 12:48 AM
Post: #5




RE: HP 50g  How to log and edit RPN expression entry?
(01172016 12:44 AM)BruceH Wrote: If you want to do calculations in RPL and somehow maintain a history of what was typed so that you can go back and edit it, then that is not possible on the 50G. How would the calculator know when you started a calculation so it would know how far back to let you go? Or would you want it to keep a record all the way back to when you turned it on? That's unfortunate. 

01172016, 03:12 AM
Post: #6




RE: HP 50g  How to log and edit RPN expression entry?
To an experienced TI84 user, the 50g certainly does feel awkward, and the opposite is equally true. I can attest to the latter personally, I tried.
It sounds like you are trying to use the 50g the same way you use the TI, and it simply will not work that way, at least not comfortably or easily, as it wasn't intended to be used that way. But I believe you will find it is very consistent and predictable, once you spend time learning to use it as intended. In the opposite sense, as an experienced RPL user, I tried to pick and use my son's TI84 and was not only confused, I couldn't even get it to do simple things. Nearly ready to just toss it, my son gave me some sage advice: RTFM. So, I did and suspended all prior "knowledge" of how to use a calculator intuitively (which after 40 years of RPN and RPL was extremely biased). But by just following the manual (and some online tutorials I found) I was suddenly able to use it and do meaningful stuff. Ultimately, it was just idle curiosity, and I petty much dropped it, but the exercise was primarily to understand just how 'good' or 'bad' it really was. Obviously it turned out it was neither of those, just different, or maybe more to the point, it was not to my taste. All that comes down to this: try to learn using the 50g the way it was intended to be used and I think you will be far more satisfied, but more importantly, will be able to effectively use some of the features that justified your switching in the first place. HTH Bob Prosperi 

01172016, 03:46 AM
Post: #7




RE: HP 50g  How to log and edit RPN expression entry?
(01172016 03:12 AM)rprosperi Wrote: But by just following the manual (and some online tutorials I found) I was suddenly able to use it and do meaningful stuff. I never knew the TI84+ had a manual, and I don't like the thought of slogging through it. I figured everything out through trial and error, and Googling. Why would HP calculators need a manual to use effectively? ... Either it's more difficult to relearn how to use a calculator, than to learn it initially. Or HPs are just less intuitive or easytouse. Also, the 50g is more sophisticated and complex than the 84+ (CAS, units, ARM, etc.), though unfortunately not much faster (in my experience). What's the difference between the 50g manual, and the guide? The guide is longer. 

01172016, 09:40 AM
Post: #8




RE: HP 50g  How to log and edit RPN expression entry?
The RPN way. :)
Greetings, Massimo +×÷ ↔ left is right and right is wrong 

01172016, 10:16 AM
(This post was last modified: 01172016 02:44 PM by Marcio.)
Post: #9




RE: HP 50g  How to log and edit RPN expression entry?
(01172016 03:46 AM)jimbo1qaz Wrote: ... the 50g is more sophisticated and complex than the 84+ (CAS, units, ARM, etc.), though unfortunately not much faster (in my experience). If you are having too much trouble with the 50g and don't want to read the manuals (yes, it's necessary due to the complexity of the machine), why don't you just drop it and pick up an HP Prime? The Prime is MUCH faster and easier to use. For those who have some kind of experience with TIs and want to take the HP road for a change, the Prime offers the shortest path to satisfaction! 

01172016, 03:49 PM
Post: #10




RE: HP 50g  How to log and edit RPN expression entry?
(01172016 03:46 AM)jimbo1qaz Wrote: I never knew the TI84+ had a manual, and I don't like the thought of slogging through it. I figured everything out through trial and error, and Googling. Why would HP calculators need a manual to use effectively? ... Either it's more difficult to relearn how to use a calculator, than to learn it initially. Or HPs are just less intuitive or easytouse. Perhaps if you trial/error and google with the 50g as long as you did with the TI84, you'll learn as much, but expecting to effectively use a machine with literally thousands of functions that way isn't reasonable. With power comes the need to learn to use it well. I agree with Marcio the Prime may have been a better choice (for easier transition) but since you already bought a 50g, we're trying to give you advice on how best to accomplish what you want. Both manuals are useful, but much of the material in both of them is reference (to look up how to use specific functions for specific applications), so one would not need to read them all the way through. Since you can freely download them, I suggest you get copies of both and peruse the contents, I think it will be fairly obvious which parts you will need to use. Regarding performance, I believe you will find the 50g notably faster when running programs (vs. realtime response) however I honestly can't be sure as I've not done much programming on the TI84. Good luck with learning the 50g, I think you will be impressed with it's capabilities if you have the patience to work through the transition. Bob Prosperi 

01172016, 09:45 PM
Post: #11




RE: HP 50g  How to log and edit RPN expression entry?
My first 2 calculators were the TI SR10 and SR11, from the early 70's. An instructor in one of my engineering classes had an HP 45, which had all the bells and whistles of that era. I was hooked. Learning how to manipulate the stack took a little bit of doing for me, but once mastered, I marveled at the ease of doing manual calculations with a stack (no parenthesis), and still today I prefer RPN/RPL over algebraic for manual calculations.
Stack calculations require a different mind set than algebraic. You Must understand how the stack operates, or you'll just frustrate yourself. I visualize the stack as just a stack of numbers, one on top of the other. RPN generally implies a 4 level stack, RPL generally implies an infinite stack (at least until you run out of memory). You have more instructions available to manipulate the RPL stack, but for both, you're generally working with the bottom 2 registers, RPN calls them X and Y, RPL calls them Level 1 and Level 2. There are tutorials on how the stack operates on this website. Please check them out. For performance of user written programs (I program in User RPL on the HP50g, and TI Basic on the TI89 Titanium). I have found that the programs that I run (mostly engineering types), will generally get an answer within 2 or 3 seconds of each other, which is close enough for me. If you want to check one out, there is a program called FluidTI for the TI84+ (located at ticalc.org), and the same program called FluidHP for the HP50g (located at hpcalc.org). That should give you some idea of program performance. Perservere in learning how the stack operates, and I don't think you'll regret your decision for purchasing the HP50g. 

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