RPN/RPL is still relevant

[Matt Agajanian]

Hello all.

Please bear with me as I try to compose my thoughts.

As a calculator collector, programmer, enthusiast, etc for 42 years, I've fiddled with quite a few logic systems. Although my Sharp and Casio acquisitions are sparse, I've familiarised myself with D.A.L., V.P.A.M. and WriteView.

Since I've also collected HPs all the way from Classics to the 50g and the Corvus 500 clones, I've used both RPN and RPL.

As a TI user since the SR-50 and 56 as well as TI-58C and currently the 86, 89 and nSpire CX CAS, I've used the rudimentary AOS of the SR-50 as well as the fully matured AOS of the SR-56 and TI-58C. And, I've delved into the logic systems of the aforementioned graphing TIs as well.

To the point, as each non-RPN entry method has morphed into more of a true infix and authentic math typesetting entry, they still necessitate the algebraic punctuations and groupings so as to remove ambiguity (ie parentheses, commas). In other words, although these entry methods have improved on fostering a natural entry scheme to the point of being much more natural forms of expression and not forcing the user into a steep learning curve, they've yet to achieve the full efficiency of RPN and RPL methodologies.

Any thoughts?

Thanks

[Mike Morrow]

(04-08-2014 12:44 AM)Matt Agajanian Wrote:  As a calculator collector, programmer, enthusiast, etc for 42 years...

Wow! That takes you back to an era just before the HP-35 (equivalent cost $2300 in 2014) appeared, when even the four-function Bomar 901B cost the 2014 equivalent of $800. Impressive...unless you were very wealthy! :-)

I was a junior in electrical engineering at Georgia Tech in 1972, and that Bomar 901B was all I could afford. Well...in truth...I really could not afford it

With respect to the topic...Casio's V.P.A.M. (Visually Perfect Algebraic Method) is one of the best algebraic entry and display methods I've ever come across...in my 42 years. You can enjoy its use in the fx-115ES Plus sold at every Walmart for less than $18. Its Gauss-Kronrod numerical integration function is better than anything from TI or HP, AFAIK. Here is the fx-115ES Plus Manual.

[HP67]

On the surface (no pun intended) after a 20 second look VPAM doesn't offer anything the HP hasn't offered at least since the HP 48 (1990) or possibly earlier.

How would you compare VPAM to HP's Equation Writer? Not that Equation Writer is so intuitive...

I was intested in the 115/991 ES Plus after reading Eddie Shore's excellent blog, but another poster here, Stefan, pointed out some shortcomings of the 115/991 in another thread.

[Matt Agajanian]

From my usage of my Casio 115es Plus, the V.P.A.M. interface does have a somewhat shallow complexity to its usability, meaning the math typesetting on this one is fairly straightforward, much like the 48 onward.

[Mike Morrow]

(04-08-2014 05:14 PM)Matt Agajanian Wrote:  ...the V.P.A.M. interface does have a somewhat shallow complexity to its usability, meaning the math typesetting on this one is fairly straightforward, much like the 48 onward.

I'm not sure what "somewhat shallow complexity to its usability" means, even though the following clause purports to explain...does "on this one" refer to a fx-115ES Plus?
Does your statement actually mean "VPAM is less complex for algebraic entry of a specific task" than are other algebraic systems? If so, I think we agree...in that case your at first glance disparaging term "somewhat shallow complexity" is a <b>positive attribute</b>! :-)

I challenge anyone to cite a current calculator that sells for $13 to $18 (US) which has an algebraic entry and display interface as natural and powerful as Casio's VPAM.

[Steve Simpkin]

(04-08-2014 05:47 PM)Mike Morrow Wrote:  I challenge anyone to cite a current calculator that sells for $13 to $18 (US) which has an algebraic entry and display interface as natural and powerful as Casio's VPAM.

I think the Sharp EL-W516XB (and similar models) and also the TI-36 Pro are in the same general category.

There is a good comparison between the SHARP EL-W516 and the CASIO fx-115ES calculators at:
http://members.bex.net/jtcullen515/Math8.htm

More than a simple comparison, the two volumes presented here (175 pages) are also a good tutorial on how to use these models with a lot of examples. The information is usable for newer Casio and Sharp scientific calculator models as well.

[Mike Morrow]

(04-08-2014 11:08 AM)HP67 Wrote:  I was intested in the 115/991 ES Plus after reading Eddie Shore's excellent blog, but another poster here, Stefan, pointed out some shortcomings of the 115/991 in another thread.

You were done a disservice!!! :-) I have never come across a machine even remotely as capable for the price as is the fx-115ES Plus (here...mechanical calc user since 1969, electronic calc user since 1972). If only it were programmable! It's so extremely low priced, there's no excuse for any calculator nut to not buy and try!

[Matt Agajanian]

(04-08-2014 07:04 PM)Mike Morrow Wrote:  

(04-08-2014 11:08 AM)HP67 Wrote:  I was intested in the 115/991 ES Plus after reading Eddie Shore's excellent blog, but another poster here, Stefan, pointed out some shortcomings of the 115/991 in another thread.

You were done a disservice!!! :-) I have never come across a machine even remotely as capable for the price as is the fx-115ES Plus (here...mechanical calc user since 1969, electronic calc user since 1972). If only it were programmable! It's so extremely low priced, there's no excuse for any calculator nut to not buy and try!

I concur. For its under $25 tag, the 115es Plus is well populated with not only advanced statistics but even more advanced calculus functionality than the pocket-change price would suggest. I must say, between the 36X Pro, EL-W516X and 115ES Plus, Casio's model does provide more bang for the buck!

[HP67]

So check out Sharp's EL-W506 which is in the same price range and see how it stacks up.

When everybody agrees... (I'm a late adopter!)

[Steve Simpkin]

(04-08-2014 07:37 PM)HP67 Wrote:  So check out Sharp's EL-W506 which is in the same price range and see how it stacks up.

When everybody agrees... (I'm a late adopter!)

The Sharp EL-W506 is essentially the same as the EL-W516.
There is a good comparison between the SHARP EL-W516 and the CASIO fx-115ES calculators at:
http://members.bex.net/jtcullen515/Math8.htm

[Matt Agajanian]

(04-08-2014 05:47 PM)Mike Morrow Wrote:  

(04-08-2014 05:14 PM)Matt Agajanian Wrote:  ...the V.P.A.M. interface does have a somewhat shallow complexity to its usability, meaning the math typesetting on this one is fairly straightforward, much like the 48 onward.

I'm not sure what "somewhat shallow complexity to its usability" means, even though the following clause purports to explain...does "on this one" refer to a fx-115ES Plus?
Does your statement actually mean "VPAM is less complex for algebraic entry of a specific task" than are other algebraic systems? If so, I think we agree...in that case your at first glance disparaging term "somewhat shallow complexity" is a <b>positive attribute</b>! :-)

I challenge anyone to cite a current calculator that sells for $13 to $18 (US) which has an algebraic entry and display interface as natural and powerful as Casio's VPAM.

You're right. My goof, awkward choice of words on my part. What I should've said was that the interface and its templates-based input is much more user intuitive, and visually obvious and thus, the shallow learning curve was meant to convey the 'right out of the packaging' usability instead of needing to leaf through a manual.

Sorry for the mix-up.

[davetheguru]

Since my first HP, an HP-45, with a stack and RPN, with X<>Y, RDN, etc., give me anything else and I'll throw it back asking "where's the ENTER button?" Parenthesis give me a headache.
RPN is SO efficient if you know how to use it and its associated tools.

[Thomas Klemm]

(04-10-2014 03:28 AM)davetheguru Wrote:  Parenthesis give me a headache.

No conditions to program with Lisp.

[Matt Agajanian]

(04-10-2014 03:28 AM)davetheguru Wrote:  Since my first HP, an HP-45, with a stack and RPN, with X<>Y, RDN, etc., give me anything else and I'll throw it back asking "where's the ENTER button?" Parenthesis give me a headache.
RPN is SO efficient if you know how to use it and its associated tools.

You see my point! Any logic system (or even language) which is heavily dependent on extra symbols or punctuation so as to remove/avoid ambiguity is higly inefficient. That's what makes RPN such a model of simple elegance. Its straightforward syntax and structure completely fulfill the idea of flawless mathematical and logic methodologies.

[HP67]

(04-10-2014 04:45 AM)Thomas Klemm Wrote:  

(04-10-2014 03:28 AM)davetheguru Wrote:  Parenthesis give me a headache.

No conditions to program with Lisp.

I heard the secret of LISP is to ignore the parenthesis. That's what Emacs is for, anyway.

[Thomas Radtke]

(04-10-2014 07:31 AM)HP67 Wrote:  That's what Emacs is for, anyway.

Ah! Talking about Emacs: Another example for a superior product w/o any chance for the mass market. Even on Win I'm using Jasspa's MicroEmacs just for the powerful keyboard macro functionality. Still unbeaten by Textpad, Notepad++ etc, it does multiple searches within macros, allowing for highly configurable replacement operations that saved me lots of hours writing scripts or doing things manually.

RPN plays in the same league. Powerful but not attractive to people used to swim in the mainstream.

[HP67]

Yes, I must admit. For most platforms you can't get a better operating system than Emacs. And it's a heck of a good text editor, too

[Thomas Klemm]

You might like: GNU Emacs Calculator

[CR Haeger]

(04-10-2014 04:57 AM)Matt Agajanian Wrote:  

(04-10-2014 03:28 AM)davetheguru Wrote:  Since my first HP, an HP-45, with a stack and RPN, with X<>Y, RDN, etc., give me anything else and I'll throw it back asking "where's the ENTER button?" Parenthesis give me a headache.
RPN is SO efficient if you know how to use it and its associated tools.

You see my point! Any logic system (or even language) which is heavily dependent on extra symbols or punctuation so as to remove/avoid ambiguity is higly inefficient. That's what makes RPN such a model of simple elegance. Its straightforward syntax and structure completely fulfill the idea of flawless mathematical and logic methodologies.

Coming from a 15C a long time ago, I generally agree. "Efficiency" sometimes depends on the calculation(s) being performed. If you make a keying error during the RPN entry, you may be able to recover via an UNDO key if available. If not, you get to inefficiently reenter stuff.

I will say that algebraic entry (TI36x, HP Prime for me) can offer some visual feedback of the expression entered and some useful copy/pasting of prior expressions.

Best,
Carl

[Matt Agajanian]

(04-10-2014 04:29 PM)CR Haeger Wrote:  

(04-10-2014 04:57 AM)Matt Agajanian Wrote:  You see my point! Any logic system (or even language) which is heavily dependent on extra symbols or punctuation so as to remove/avoid ambiguity is higly inefficient. That's what makes RPN such a model of simple elegance. Its straightforward syntax and structure completely fulfill the idea of flawless mathematical and logic methodologies.

Coming from a 15C a long time ago, I generally agree. "Efficiency" sometimes depends on the calculation(s) being performed. If you make a keying error during the RPN entry, you may be able to recover via an UNDO key if available. If not, you get to inefficiently reenter stuff.

I will say that algebraic entry (TI36x, HP Prime for me) can offer some visual feedback of the expression entered and some useful copy/pasting of prior expressions.

Best,
Carl

I'm curious. Although I adhere to LSTx as a fine example of an error recovery tool, how do you see the efficiency and usefulness of 'Last X' on non-RPL HP's?