HP 50g questions

[Lode]

Hi,

A few things I'm wondering about the HP 50G:

1. Does it support operations like sqrt/exp/log/... on matrices? HP Prime does in CAS mode only, but on HP 50g it only gives "Bad Argument Type". Is there any way, e.g. with some combination of modes?

2. In RPN mode, you are required to hold down shift and F keys at the same time to use the graph functions rather than first shift then F key. Why is this, and why only in RPN? It's a bit of an unintuitive and painful key combination to execute.

3. Is there any way to visually see if there is a next menu for the "nxt" button at the horizongal buttom menu row (without trying by actually pressing "nxt")?

4. If I would download a program that has "erf" and "erfc" functions (or program them), is there any way that you can then add these erf and erfc in the built-in "special functions" menu or can custom functions only go in different menus?

Thanks

[John Keith]

A few possible answers...

1) If what you want is to apply the function to each element in the matrix, you need to convert the matrix to a list, apply the function to the list, then convert back to a matrix. In general, unless you are doing linear algebra operations ( inverse, determinant, etc.) lists are more versatile than matrices.

2) Can't answer that one, I never use the graphing commands.

3) I don't think so.

4) You can't add user programs to built-in menus, your best bet is the Custom menu.

John

[Lode]

Thanks for the answers!

For 1), I didn't mean the elementwise operation, but the matrix exponential and other such operations, which can be computed for example with jordan form

[DavidM]

(03-23-2019 09:52 AM)Lode Wrote:  2. In RPN mode, you are required to hold down shift and F keys at the same time to use the graph functions rather than first shift then F key. Why is this, and why only in RPN? It's a bit of an unintuitive and painful key combination to execute.

I don't possess any inside documentation about this, but I suspect that it stems from previous precedents that were already set for left- and right-shifted F1-F6 keys in RPN mode. Specifically, left-shift F1 (or F2, F3...) will store whatever is in stack level 1 into the global variable whose name appears above that key in the main menu. Similarly, right-shift F1 (etc.) will recall the contents of the named global variable designated by that key to the stack. Since those functions were already defined, shift-hold functions were probably used as an alternative when those graphic functions were added.

(03-23-2019 09:52 AM)Lode Wrote:  3. Is there any way to visually see if there is a next menu for the "nxt" button at the horizongal buttom menu row (without trying by actually pressing "nxt")?

No built-in way, but it would be possible for a "System Outer Loop" replacement to implement such a feature. Perhaps someone knows if that type of function has already been created in a third-party app. Anyone know if this has already been implemented in an app or library?

(03-23-2019 09:52 AM)Lode Wrote:  4. If I would download a program that has "erf" and "erfc" functions (or program them), is there any way that you can then add these erf and erfc in the built-in "special functions" menu or can custom functions only go in different menus?

Thanks

If what you mean by "special functions" menu is the one that results when you press the APPS key, it's possible to do that with a customized library. If what you mean is the "CUSTOM" menu (which places items in the menu area of the display above the F1-F6 keys), that can be done very easily by storing appropriate items in a list variable named 'CST'. Once that variable has been created, activate the menu with the CUSTOM command (left-shift MODE).

[Gerald H]

This programme does point 1.

Code:

::
  CK2&Dispatch
  # 48
  ::
    2DUP
    FPTR2 ^PUSHFLAGS_
    FPTR2 ^CLREXACT
    BINT103
    SetSysFlag
    FPTR 7 134
    FPTR2 ^POPFLAGS_
    3UNROLL
    xDROP2
  ;
;

eg For stack

[[ 4 5 ]
[ 3 8 ]]

<< SQRT >>

the programme returns the square root of the matrix in level 2.

The programme is posted in the General Software section but I can't remember where.

[Lode]

I found an interesting thread referencing your program here:

http://www.hpmuseum.org/forum/thread-3786.html

Found by searching for "BINT103", for which I searched because to be honest I've got no clue what this program is doing! It seems to be a lot about flags, I'm trying to see anything that's an actual meaty matrix operation operation in those commands but none look like that. What's the main magic command in there?

EDIT: found it, it's DIAGMAP, and it's available in the catalog of the 50g by that name (and is the "FPTR 7 134" above)

[Gerald H]

Very good digging, Lode - I had forgotten the User command DIAGMAP.

Trust your point 1 is answered.

[Lode]

> Trust your point 1 is answered.

Yes, for sure, I wonder how many more hidden powerful commands are in there

[TravisE]

(03-24-2019 12:05 AM)DavidM Wrote:  

(03-23-2019 09:52 AM)Lode Wrote:  2. In RPN mode, you are required to hold down shift and F keys at the same time to use the graph functions rather than first shift then F key. Why is this, and why only in RPN? It's a bit of an unintuitive and painful key combination to execute.

I don't possess any inside documentation about this, but I suspect that it stems from previous precedents that were already set for left- and right-shifted F1-F6 keys in RPN mode. Specifically, left-shift F1 (or F2, F3...) will store whatever is in stack level 1 into the global variable whose name appears above that key in the main menu. Similarly, right-shift F1 (etc.) will recall the contents of the named global variable designated by that key to the stack. Since those functions were already defined, shift-hold functions were probably used as an alternative when those graphic functions were added.

In fact, there are several other keys that change their behavior depending on whether you press and release the shift key or keep it held down while pressing the other key. It can take some getting used to, and the key labels certainly don't make this behavior very clear, but it does allow more features to be accessed (or assigned by the user) on the keyboard since it doubles the effective number of shift keys available.

[Joe Horn]

(03-28-2019 01:49 AM)TravisE Wrote:  In fact, there are several other keys that change their behavior depending on whether you press and release the shift key or keep it held down while pressing the other key. ...

34 of the 50g's built-in press-and-hold key combinations are listed in Appendix G ("Keyboard Shortcuts") of the Advanced User's Reference Manual. I think the only one missing is the three keys B, C, and D, which, if held down throughout a warmstart, puts the 50g into "Smart Mode" (RPN and a few other settings). This unsupported feature was added during product development by Cyrille de Brebisson for his own use, and he nicely left it in for the rest of us to use. He chose those three keys not because BCD stands for Binary Coded Decimal, but because they are his own initials.

[franz.b]

(03-28-2019 04:57 AM)Joe Horn Wrote:  34 of the 50g's built-in press-and-hold key combinations are listed in Appendix G ("Keyboard Shortcuts") of the Advanced User's Reference Manual. I think the only one missing is the three keys B, C, and D, which, if held down throughout a warmstart, puts the 50g into "Smart Mode" (RPN and a few other settings). This unsupported feature was added during product development by Cyrille de Brebisson for his own use, and he nicely left it in for the rest of us to use. He chose those three keys not because BCD stands for Binary Coded Decimal, but because they are his own initials.

strong!
but I don't seem to succeed ... warmstart is what happens after on-C? how do you recognize access to this smart mode?

[Joe Horn]

(03-28-2019 07:18 AM)franz.b Wrote:  strong!
but I don't seem to succeed ... warmstart is what happens after on-C? how do you recognize access to this smart mode?

Yes, warmstart by pressing ON+C, but then immediately press and hold down all three keys B+C+D until the warmstart finishes. One visible effect is that the 50g will boot up in RPN mode instead of the default Algebraic mode. It also sets system flags -60 (single-ALPHA lock) and -62 (USER mode on). I *think* those are the only effects it has.

[franz.b]

(03-28-2019 12:10 PM)Joe Horn Wrote:  Yes, warmstart by pressing ON+C, but then immediately press and hold down all three keys B+C+D until the warmstart finishes. One visible effect is that the 50g will boot up in RPN mode instead of the default Algebraic mode. It also sets system flags -60 (single-ALPHA lock) and -62 (USER mode on). I *think* those are the only effects it has.

so I succeeded