PLEASE PLEASE an Undo

[luisphysics]

OMG please please I would love to have a few undo for the input line on either home and CAS. I was just plugging in a rather complicated formula with units and I stinking pressed Shift+Esc BUT I was trying to press the SHIFT+USER button and I failed. This one feature should honestly be like top priority above anything. Granted I should know how to do unit analysis and I do, but I get lazy sometimes or as in this case I want a sanity check(since I'm tired and stressed) from something I trust.

For now I will just suffer.

[informach]

Hi!, luisphysics:

Can you, explain better ?. In your calculations, you can copy and save, in Notes, or create an APP.

Kind Regards.
informach.

[eried]

You can't undo real life.

[Eddie W. Shore]

(04-30-2016 08:10 PM)eried Wrote:  You can't undo real life.

Very true. Through an UNDO feature would come in handy sometimes.

[cyrille de brébisson]

Hello,

This would make a wonderful premise to a sci fi novel!

Can you imagine all the implications? The first that pops in mind is for a criminal, he would undo a robbery only when caught... but the law should still be able to catch him because he had intent...
How far in the past could you undo? How deep is the undo stack? how reliable is the undo? does it mean that you will, after the undo, remember what you undid?


Cyrille

[DrD]

(05-02-2016 06:18 AM)cyrille de brébisson Wrote:  does it mean that you will, after the undo, remember what you undid?
Cyrille

undefinitely, unless I undidn't understand ...

-Dale-

[primer]

(05-02-2016 09:27 AM)DrD Wrote:  

(05-02-2016 06:18 AM)cyrille de brébisson Wrote:  does it mean that you will, after the undo, remember what you undid?
Cyrille

undefinitely, unless I undidn't understand ...

I think Cyrille speak about "redo" here ("redo hat you already undid") which is often see as optional. (for ex "redo" didn't exist in hp48), requesting "infinite" here may cost a lot.

"undefinitely" is maybe the answer about undo stack size question...

(05-02-2016 06:18 AM)cyrille de brébisson Wrote:  How far in the past could you undo? How deep is the undo stack?

BTW,
Shall the undo do cover entry manipulation ? (changing currently edited entry)
or shall it cover also "stack"/history operation ? (drop an item...)

[luisphysics]

What do I mean? Ok for example on my Ti-inspire if I am typing an equation say
// Ok I'm gonna give a trivial example

10-1

and before pressing enter I accidently press ctrl+del
I think oh no!!!!!
Then I think ...wait TI has undo
I can press ctrl+z

and then 10-1 is back on the input screen.

It doesn't record each button press but that is fine... it is something.
...................
What about Prime? No such luck.

[informach]

Hi!, luisphysics:

You can install, the ... http://www.hpcalc.org/details.php?id=7652

Note: Saves the current version, of a program, while editing it, using user keys. Restores, saved version (UNDO changes). Second call, also allows, to rollback UNDO, operation (REDO).

Kind Regards.
informach.

[eried]

(05-02-2016 02:32 PM)luisphysics Wrote:  What do I mean? Ok for example on my Ti-inspire if I am typing an equation say
// Ok I'm gonna give a trivial example

10-1

and before pressing enter I accidently press ctrl+del
I think oh no!!!!!
Then I think ...wait TI has undo
I can press ctrl+z

and then 10-1 is back on the input screen.

It doesn't record each button press but that is fine... it is something.
...................
What about Prime? No such luck.

Hahah yeah we all know Prime lacks this, it is one of the most requested enhancements http://www.tricider.com/brainstorming/2eKfifdjarx but I estimate that it is going to arrive in the next 4 updates, circa 2020

[HP67]

(04-30-2016 08:10 PM)eried Wrote:  You can't undo real life.

That's just silly and wrong. Don't you remember what Marty McFly said? "The past is gonna change!"

We already had a flux capacitor thread, check the forum.

;-)

[luisphysics]

It would be interesting to find out why this feature wasn't introduced in the initial planning of the prime software. Maybe there was a trade between and undo and some other feature that we don't know about. Or it might not have been important enough.

Under the premise that the HP Prime was designed for education. Kids tend to make mistakes. So it would make sense to "me" to make the software at least a little forgiving of mistakes.
Maybe the math educators testing the software didn't want an undo mechanism. But in America you are expected to use a pencil, because the teacher tell you that it is easier to fix a mistake, and it allows you to make your homework pretty so that they can grade it.

If this feature doesn't come I will live, but it doesn't mean I will be happy.

[leprechaun]

The prime was made with two things in mind: Save time and development cost.
That is why an older codebase was used to form a conglomerate with the giac code. If in the 39 there is no undo - that is the reason why the prime lacks it.

Personally I pity other things, but it is an individual thing. (btw the HP advertising I read before purchasing my prime said that it is the perfect tool for science and engineering and not the perfect tool for students)

It seems that HP (or more precisely the development team - I would not necessarily include the managment) is working hard to make cas and home interact much more smoother. I don't know how much they can achieve or if it would be better to start working on a new calculator from scratch at some point (HP the bechnmark in calculator again! Imagine that)
If they can do it, they will introduce the undo. I am sure of that, but I am unsure if there were not more beneficial improvements for the calculator they should go for, first.

[leprechaun]

(05-04-2016 11:18 AM)leprechaun Wrote:  The prime was made with two things in mind: Save time and development cost.
That is why an older codebase was used to form a conglomerate with the giac code. If in the 39 there is no undo - that is the reason why the prime lacks it.

Personally I pity other things, but it is an individual thing. (btw the HP advertising I read before purchasing my prime said that it is the perfect tool for science and engineering and not the perfect tool for students)

It seems that HP (or more precisely the development team - I would not necessarily include the managment) is working hard to make cas and home interact much more smoother. I don't know how much they can achieve or if it would be better to start working on a new calculator from scratch at some point (HP the bechnmark in calculator again! Imagine that)
If they can do it, they will introduce the undo. I am sure of that, but I am unsure if there were not more beneficial improvements for the calculator they should go for, first.

Quote:From my point of view, The UNDO option should be as simpler as recovering the last action, by retrieving the contents of the last stack, and put back on the entry line, That's it!.

I would NOT bet a penny on that statement ;-)))

[compsystems]

we also need quick access to the latest entries, as to the hp48 LASTCMDs CHOOSE, It is a more practical way to explore history

[SHIFT] hold + [ENTER] = LASTCMDs

you agree with me?

[Tim Wessman]

(05-05-2016 03:00 AM)compsystems Wrote:  [SHIFT] hold + [ENTER] = LASTCMDs

Shift-paste (4 entries already there)

[compsystems]

there is a problem, [SHIFT]+[PASTE] it is not 100% functional =[

example

x / y [ENTER]
ans + 5 [ENTER] (x / y)+5
ans / z [ENTER] ((x / y)+5)/z
ans * 3 [ENTER] (x/y+5)/z*3

by rerunning the entries [SHIFT]+[PASTE], you lose ANS pointer,


One possible solution is that ANS should be evaluated in history as does calculators ti68K or here is also a ENTRY (#) command to call the input line

[cyrille de brébisson]

Hello,

They are 2 big issues with undo.

1) What do you undo? I can type a command line command that, for example, overrides a file (AFiles("a.png"):= G0). What does undo do here.
Of course, this is an extreme example, but just something as simple as A:=0 is not a simple thing to undo...
I can type a command line that creates and override a whole program!

So, doing a simple undo that works in the home command line is already quite complex. I guess I could take a snapshot of the memory and save it... but that takes a lot of RAM!

2) The point above was just about undo for the home screen. But undo means different things in every view of the system. And would need to be implemented in every view of the system! Although some places could share a generic code, in most cases, it would mean a LOT of SW development to get a good working undo.


More than anything else, I think that these 2 points are why UNDO is low on the radar. It is hard to implement, and it takes a LOT of time to implement. This makes it a function which, while having a high value, also has a high cost, giving it an overall low priority factor.

Note that these statements are in no way "forward looking", just my personal musings. I would personally love to have Undo on Prime.

Cyrille

[eried]

Undo ONLY needs to work in the input text boxes. I don't think anyone is dreaming a whole complete constant snapshot based-UNDO.

Up to N steps, just save the input differential after 'some actions'.

Example: after an operand,

Code:

2x+
*UNDO*
2x
*UNDO*

*REDO*
2x

Example: after a newline/Del/Clear,

Code:

2x+
*DEL*

*UNDO*
2x+

Menu key suits perfectly for Redo/Undo commands, and ON+Z, ON+Y as the key combinations