What are you referring to here?
Free42 Version 3
-
- Posts: 1100
- Joined: Tue May 02, 2017 5:48 pm
- Location: Netherlands
- Contact:
Re: Free42 Version 3
Please look up the HP-42S Owner's Manual, p. 45, or the WP43S Owner's Manual, pp. 34f, or the WP34S Owner's Manual, p. 39.
WP43 SN00000, 34S, and 31S for obvious reasons; HP-35, 45, ..., 35S, 15CE, DM16L S/N# 00093, DM42β SN:00041
-
- Posts: 1100
- Joined: Tue May 02, 2017 5:48 pm
- Location: Netherlands
- Contact:
Re: Free42 Version 3
And which calculators we were talking about here do not possess this feature?
UPDATE: Argh, I should have pushed harder here. Now it may look as though Walter wasn't spreading nonsense about Free42.
Just to be clear: Free42 does have automatic stack lift, regardless of which mode it is in. Pointing out that the wp43 has this feature appears to have been meant to imply that Free42 in big stack mode doesn't, and that is not true.
Moderators, could you delete or at least annotate Walter's post to that effect? I don't think it's good manners to spread deliberate misinformation here.
UPDATE: Argh, I should have pushed harder here. Now it may look as though Walter wasn't spreading nonsense about Free42.
Just to be clear: Free42 does have automatic stack lift, regardless of which mode it is in. Pointing out that the wp43 has this feature appears to have been meant to imply that Free42 in big stack mode doesn't, and that is not true.
Moderators, could you delete or at least annotate Walter's post to that effect? I don't think it's good manners to spread deliberate misinformation here.
Last edited by Thomas Okken on Mon Mar 01, 2021 10:30 pm, edited 1 time in total.
Re: Free42 Version 3
Technically you are right. 40 years we have 4 stack levels and that was ok. Having 8 will do much more.Walter wrote: ↑Sun Feb 28, 2021 6:37 pmThis is debatable. Actually, we have shown with the WP34S that all real-world calculations can be done with just an 8-level stack at zero risk of stack overflow. We continue offering such a stack with the WP43S, keeping the benefits of RPN (automatic stack lift, top stack level repetition).
But unlimited stack is not just a very large stack. This is a very different technique of programming, not reachable with limited stack of any size.
IMHO WP43S placement slightly differs from free42. Thus it cannot be used as representative example of usefulness of unlimited stack. I think having a stack more than 4 for HP 41 is really wrong idea. That machine benefits of such short stack. But for DM42 it is really good to have such opportunity, especially if it can be dynamically switched
Electronica MK-61, HP-50G, HP-Prime, DM41, DM42, DM41X
-
- Posts: 795
- Joined: Wed May 03, 2017 7:46 pm
- Location: Malone, NY USA
Re: Free42 Version 3
Maybe calculations can get by with eight levels but recursive function calls that put parameters on the stack will need many more than eight.Walter wrote: ↑Sun Feb 28, 2021 6:37 pmThis is debatable. Actually, we have shown with the WP34S that all real-world calculations can be done with just an 8-level stack at zero risk of stack overflow. We continue offering such a stack with the WP43S, keeping the benefits of RPN (automatic stack lift, top stack level repetition).
Tom L
Some people call me inept but I'm as ept as anybody!
DM10L SN: 059/100
DM41X SN: 00023 (Beta)
DM41X SN: 00506 (Shipping)
DM42 SN: 00025 (Beta)
DM42 SN: 00221 (Shipping)
WP43 SN: 00025 (Prototype)
Some people call me inept but I'm as ept as anybody!
DM10L SN: 059/100
DM41X SN: 00023 (Beta)
DM41X SN: 00506 (Shipping)
DM42 SN: 00025 (Beta)
DM42 SN: 00221 (Shipping)
WP43 SN: 00025 (Prototype)
Re: Free42 Version 3
Recursive functions are covered by local registers.toml_12953 wrote: ↑Mon Mar 01, 2021 2:50 amMaybe calculations can get by with eight levels but recursive function calls that put parameters on the stack will need many more than eight.Walter wrote: ↑Sun Feb 28, 2021 6:37 pmActually, we have shown with the WP34S that all real-world calculations can be done with just an 8-level stack at zero risk of stack overflow. We continue offering such a stack with the WP43S, keeping the benefits of RPN (automatic stack lift, top stack level repetition).
WP43 SN00000, 34S, and 31S for obvious reasons; HP-35, 45, ..., 35S, 15CE, DM16L S/N# 00093, DM42β SN:00041
Re: Free42 Version 3
This is not too hard to implement without unlimited stack.toml_12953 wrote: ↑Mon Mar 01, 2021 2:50 amMaybe calculations can get by with eight levels but recursive function calls that put parameters on the stack will need many more than eight.
But there is a very powerful function which usually called MAP.
With unlimited stack it becomes real to create really awesome and powerful realization of that function. It can be the prime caliber gun to optimize really long vector calculations.
And normal implementation of MAP needs unlimited stack behavior. In fixed stack it wont go without plenty of extra stack checking code
Unlimited stack is a tool which cannot be replaced by fixed stack of any size. This is another behavior.
We have enough stack size of 4. Alas.
But unlimited stack is not for extending stack. Most of functions will continue using 2-3 stack parameters, but with unlimited stack they can be used in a very different way, which gives a huge gap of freedom for programmer, never seen in rpn systems.
Anyway unlimited stack brings no minuses, those who does not need it just does not used.
Electronica MK-61, HP-50G, HP-Prime, DM41, DM42, DM41X
Re: Free42 Version 3
I must agree: Unlimited stack size is no problem. In Version 3 there is the posibility to switch between both, 4 stack and unlimited stack size. I see no problems, only new ways of programming DM42/free42. Thomas Okken has done a very good job. Thanks !
Re: Free42 Version 3
The dynamic stack feature is great for the Free42 emulator, but it is even better on the DM42 with its multi-line display. This is why I urge the SM crew to update the DM42 with the new version 3 of Free42, even it there are no current updates for the DMCP OS or other DM42 features and bug fixes.
DM15L, S/N 00548. DM42, SN: 00159. DM41X, SN: 00973. DM32, SN 00054.
Re: Free42 Version 3
I'm in favor of updating the DM42 to the Free42 ver.3, if it doesn't create any backward compatibility issues with programs written for 4 level stack. Some of the programs I use depend on stack lift and its also one of the reasons RPN has been my choice in calculators for 40 years.HPMike wrote: ↑Mon Mar 01, 2021 6:15 pmThe dynamic stack feature is great for the Free42 emulator, but it is even better on the DM42 with its multi-line display. This is why I urge the SM crew to update the DM42 with the new version 3 of Free42, even it there are no current updates for the DMCP OS or other DM42 features and bug fixes.
Moderator note: Free42 in big stack mode does not remove stack lift
DM42 (#6476), DM41X (#458), DM15, 12 - HP 12, 17BII, 35(2), 45, HP 27S, 28S, 30B, 41CV, 41CX, 42S, 48S, 35S, HP10bII+, 12C PLAT
I may have a problem!
I may have a problem!