|Re: How about an 'RPN Excercises Page'?|
Message #24 Posted by Michael F. Coyle on 19 Mar 2003, 8:56 p.m.,
in response to message #23 by Vieira, Luiz C. (Brazil)
You wrote, concerning using vintage HP manuals: ...my only concerns are related to the different resources from one model to the other. I believe a "starting" or "reference" point would be a good choice for those who bought or recover a vintage/earlier RPN model and want to go further.
I agree. I think our target audience is people who have no RPN experience who want to become proficient.
If you have an HP10C and want to follow the examples available in the HP67 manual, chances are you'll miss the R^ (roll-up) function/key.
I was suggesting that a new owner of an old calculator get the MoHPC CD set. That way, they could learn from the correct manual and this would not be an issue. (I think the CDs have all the old manuals.)
Even with the CDs, I think there is still room for a detailed RPN tutorial. It could cover many topics in more detail than the original manual, not just explaining what the features are, but
why they work the way they do, and how to use them to their best advantage.
The problem here is that if say, half the calculators have R^ and the other half don't, and you want to write a "generic" RPN manual, how do you do it? My ideas are below. (And I agree with you, the RPN tutorial on this site is good, and it's good that it's generic.)
In this case, the best vintage manual would be the HP25 User's Manual, so you can follow almost all examples as is.
The HP-25 manual is terrific but the 25 has no R^!!!
Anyway, let's take a step back. As I see it, there are three main types of RPN in use:
Classic RPN, like on the HP-25 (I'll call this "25-style.")
HP-41 RPN, like 25-style but with many more stack manipulations possible. (Call it "41-style.")
RPL, like on the HP-48, 49. (Call it "RPL" or "48-style.")
I think a tutorial that tried to present optimum examples that work with all three styles of RPN would be too complex and would fail. I think we should concentrate on 25-style RPN and not worry for now if the examples work on the other machine. (Exception: first introductory chapter should not cover any advanced material and should be so generic that it will work on any calculator.)
I think the feature set we should have in mind is that of the HP-25, that is, 4 basic functions [+][-][*][/], [ENTER^], [CHS], [EEX], [CLx], [x<>y], [R dn], and scientific functions as needed. Perhaps also a display mode command so the user's display can match the the tutorial's.
To deal with R^, we might present the answers with and without R^:
Example: compute ...<something>...
Solution: ...<series of keystrokes>...
If your calculator has [R^], you can save two keystrokes:
...<series of keystrokes>...
Since only a small number of examples would benefit from R^, the text would not become too cluttered.
Now it is true that every calculator has its own little quirks. Prehaps the best way to deal with this is to add a chapter at the end with notes for each specific calculator. For example, the notes for the HP-35 would mention the odd CHS behavior and the fact that trig functions erase the value of T.
If you want, I can write up some sample text. And I'd be glad to look at what you come up with.