Plus42 Equations, Preview Release

[nickapos]

(12-04-2021 03:27 PM)Thomas Okken Wrote:  Vincent, thank you! And I should acknowledge that without your testing and feedback, this would have been much harder to develop. Your contribution is greatly appreciated!

I also thank Bob Prosperi, who lent me an HP-27S and gave me an HP-17B, both of which I have used extensively, to familiarize myself with the equation editor, equation syntax, and solver behavior. I was skeptical about this functionality at first, but I have come to appreciate it while studying it and attempting to reproduce it.

Of course this is only one of four major features planned for Plus42. Next week, work continues...

Hi Thomas, what are the other three major features you have planned for Plus42?

Thanks

[Thomas Okken]

The other three new features, in the order in which I'm planning to tackle them, are:

1. Attached units, like those found on the 48/49/50 series;
2. Directories, for organizing programs and variables;
3. Big screen, i.e. support for more than two lines, up to eight (or maybe more, because once you're eliminating one hard limit, why replace it with another?). I'm not planning on changing the 22-column limit, though...

[nickapos]

(12-05-2021 07:56 AM)Thomas Okken Wrote:  The other three new features, in the order in which I'm planning to tackle them, are:

1. Attached units, like those found on the 48/49/50 series;
2. Directories, for organizing programs and variables;
3. Big screen, i.e. support for more than two lines, up to eight (or maybe more, because once you're eliminating one hard limit, why replace it with another?). I'm not planning on changing the 22-column limit, though...

Awesome, thank you very much.
I am particularly interested in second and third. Free42 is my go to calculator when not close to one of my physical ones and I think I will like plus42 even more when it’s completed.

[khoree]

Hi Thomas and all,

My little contribution of a skin for Plus42.

With dedicated function keys a la DM42, so the top row keys retain their function even when menus are active. And included alpha entry at the bottom right of each key for convenience (although this would work only for the desktop with mouse).

Still a work in progress - suggestions welcome!

[Thomas Okken]

New update:

1. Fixed direct solver for named equations.
2. No longer allowing "=" in named-and-parameterized equations. FAC(N):IF(N=0:1:N*FAC(N-1)) is OK, FAC(N):RESULT=IF(N=0:1:N*FAC(N-1)) is not.
3. In variable menus for named-and-parameterized equations, now showing the parameters in black keys, and any other variables that the function references in white keys.
4. Direct solver now generates code maps for trivial solutions, i.e. when solving for a variable that is already isolated. This means you get more helpful error messages and TRACE output in such cases. (For non-trivial solutions, this is not possible, since there is no source code for those transformed equations.)
5. Lots of memory allocation failure handling added where it was missing before, particularly in the parser and code generator.

[johanw]

(12-05-2021 07:56 AM)Thomas Okken Wrote:  3. Big screen, i.e. support for more than two lines, up to eight (or maybe more, because once you're eliminating one hard limit, why replace it with another?). I'm not planning on changing the 22-column limit, though...

This immediately made me wonder if we'll ever see a Plus42 firmware for the DM42. Especially now that the first user fork of the DM42 firmware has been released.

[toml_12953]

(12-05-2021 06:40 PM)johanw Wrote:  

(12-05-2021 07:56 AM)Thomas Okken Wrote:  3. Big screen, i.e. support for more than two lines, up to eight (or maybe more, because once you're eliminating one hard limit, why replace it with another?). I'm not planning on changing the 22-column limit, though...

This immediately made me wonder is we'll ever see a Plus42 firmware for the DM42. Especially now that the first user fork of the DM42 firmware has been released.

You beat me to this question! With the expanded display, it seems like it would be a good fit.

[Marco Polo]

(12-05-2021 07:56 AM)Thomas Okken Wrote:  The other three new features, in the order in which I'm planning to tackle them, are:

1. Attached units, like those found on the 48/49/50 series;
2. Directories, for organizing programs and variables;
3. Big screen, i.e. support for more than two lines, up to eight (or maybe more, because once you're eliminating one hard limit, why replace it with another?). I'm not planning on changing the 22-column limit, though...

Awesome work.
Anyway, I wander if it is going to resemble a 48 but with RPN instead of RPL....

[Thomas Okken]

New update:

1. In the equation editor's list view, DELET now asks whether to delete the current equation, its variables, or both.
2. Implemented the last of the missing functions: SIZEC, FLOW, #T, SPPV, SPFV, USPV, USFV, N, I%YR, PV, PMT, FV. Note that the cash-flow-related functions assume that flow lists are Nx2 matrices; SIZEC simply returns the number of rows, FLOW(A:B) returns A[B:1], and #T(A:B) returns A[B:2].

UPDATE Forgot to mention: the new functions are in a new menu, under Shift-6.

(12-06-2021 08:13 AM)Marco Polo Wrote:  Anyway, I wander if it is going to resemble a 48 but with RPN instead of RPL....

That's more or less the idea...

[Albert Chan]

Hi, Thomas Okken

%I/YR code had a comment TVM seems OK, but what about that starting guess for I%YR?

I think I had a decent rate estimate, incorporate other TVM variables.
https://www.hpmuseum.org/forum/thread-12...#pid139867

[Thomas Okken]

(12-06-2021 07:51 PM)Albert Chan Wrote:  %I/YR code had a comment TVM seems OK, but what about that starting guess for I%YR?

I think I had a decent rate estimate, incorporate other TVM variables.
https://www.hpmuseum.org/forum/thread-12...#pid139867

Hmm, interesting. But how robust is that? Isn't it possible to get a division by zero, if b = 0 or 1.5?

[rprosperi]

(12-05-2021 07:56 AM)Thomas Okken Wrote:  The other three new features, in the order in which I'm planning to tackle them, are:

1. Attached units, like those found on the 48/49/50 series;
2. Directories, for organizing programs and variables;
3. Big screen, i.e. support for more than two lines, up to eight (or maybe more, because once you're eliminating one hard limit, why replace it with another?). I'm not planning on changing the 22-column limit, though...

Nice!

#1 Speaks for itself. No comment needed. Huge!

For #2, can one save an entire folder as some kind of export object to be able to share a collection of programs and vars as a single blob?

For #3, if there's no fixed limit/stack size, it will be hard for skins to be adapted. Maybe allow a toggle between 4 and 8 levels so 2 paired skins could be automatically swapped when changing stack size?

[Vincent Weber]

(12-06-2021 07:01 PM)Thomas Okken Wrote:  

(12-06-2021 08:13 AM)Marco Polo Wrote:  Anyway, I wander if it is going to resemble a 48 but with RPN instead of RPL....

That's more or less the idea...

It might have been easier to write a RPN simulator for the 48...

Joke aside, the equation language that Thomas has ported and enhanced from the 17B/27S line is much more elegant than anything the 48 has to offer wrt algebraic equations. The 48 has no equivalent of L() and G(), so ultimately you have to use RPL local variables, and to write heavy RPL programs with algebraic equations embedded inside - quite ugly.

[Thomas Okken]

(12-07-2021 03:33 AM)rprosperi Wrote:  #1 Speaks for itself. No comment needed. Huge!

Judging by the feedback I get, sometimes I get the impression nobody cares about that feature. Well, I do, and it's good to hear I'm not the only one.

(12-07-2021 03:33 AM)rprosperi Wrote:  For #2, can one save an entire folder as some kind of export object to be able to share a collection of programs and vars as a single blob?

Yes, probably. The details are still to be worked out, but I'm leaning towards making directories first-class objects, so you can copy and paste them, but also RCL and STO them all in one piece. That would make directory management nice and intuitive, without needing a lot of new UI functionality.

(12-07-2021 03:33 AM)rprosperi Wrote:  For #3, if there's no fixed limit/stack size, it will be hard for skins to be adapted. Maybe allow a toggle between 4 and 8 levels so 2 paired skins could be automatically swapped when changing stack size?

Most portrait skins could be adapted easily. As long as there's nothing elaborate going on to the left and the right of the display, the display area could be stretched vertically, and the decor along the sides could be stretched by tiling it. Given how tall many new phone screens are, they're just begging to be used that way... And all that stretching could be handled on the fly, so the display can be resized without switching skins, and this could all be done with existing skins, without them needing to be modified at all.

[Thomas Okken]

Given all the changes since the first post of this thread, I thought it might be a good idea to post a little summary of all the new Plus42 functionality...
My apologies for the somewhat random structure of this post. This is basically the concatenation of several posts, with only minimal editing. At some point, I will edit this into some proper documentation and put it on my web site.

UPDATE: I have moved this documentation to my web site: https://thomasokken.com/plus42/#doc

[roberto_abraham]

(12-07-2021 11:01 AM)Thomas Okken Wrote:  

(12-07-2021 03:33 AM)rprosperi Wrote:  #1 Speaks for itself. No comment needed. Huge!

Judging by the feedback I get, sometimes I get the impression nobody cares about that feature. Well, I do, and it's good to hear I'm not the only one.

There are at least three of us... support for units at a deep level is the feature I am looking forward to the most!

[roberto_abraham]

(12-07-2021 12:41 PM)Thomas Okken Wrote:  Given all the changes since the first post of this thread, I thought it might be a good idea to post a little summary of all the new equation functionality...

Thanks for this summary... I was getting a little lost! This new functionality is going to be incredibly handy... particularly if I can start using equations with units.

Amazing stuff... thanks again!

[rprosperi]

(12-07-2021 12:41 PM)Thomas Okken Wrote:  Given all the changes since the first post of this thread, I thought it might be a good idea to post a little summary of all the new equation functionality...

I agree, this is super helpful. I'd also suggest and recommend this information be kept updated in a PDF (or whatever) file, perhaps linked in the top post in the thread, so one can easily find the latest info on this evolving feature without having to scan numerous messages. It will probably cut down on the number of questions from users learning to use it.

[Marco Polo]

(12-07-2021 12:41 PM)Thomas Okken Wrote:  Given all the changes since the first post of this thread, I thought it might be a good idea to post a little summary of all the new equation functionality...

Thank you very much.
I was getting a little lost....
Are you planning to implement a multiple equation solver similar to HP48 MES or Solvesys?

[Thomas Okken]

(12-07-2021 09:13 PM)Marco Polo Wrote:  Are you planning to implement a multiple equation solver similar to HP48 MES or Solvesys?

No, that's not on the roadmap at the moment.