New to HP prime

[std]

Hello people,
I recently bought my HP-prime and I think it is a great calculator.
Before I ask a few questions I would like to mention that the keys are harder to press, compared to other keyboards and the orange colour for the letters makes it a little difficult to focus my eyes on. Maybe a dark red colour would be more appropriate.
Anyway, I have some questions
1) According to the latest manual, on page 514, "An attempt to store an element to a row or column beyond the size of the matrix results in resizing the matrix to allow the storage. Any intermediate cells will be filled with zeroes." but it only works on Home view, not in CAS mode. Why is that?
2) How to clear all the variables at once? I mean real, matrices from HOME tab and all the user variables?
3) In CAS settings, the number format setting doesn't seem to make any difference. Am I missing something? I also cannot find out what does the number next to it mean.
4) Is it possible to make multiple statements, like L1:=L2:=1 ?

[Steve Simpkin]

You are not alone in your remarks about the label colors.
http://www.hpmuseum.org/forum/thread-211.html

The first thing to keep in mind is that the Prime is really two different calculators in one housing. Home mode for more or less normal calculations and CAS mode for algebra. I am greatly oversimplifying this, of course, but it does help in understanding how it works.
Also remember not all functions work the same (or sometimes, at all) in both modes!

[std]

Thanks for your answer.
I mostly use CAS. I want it for structural dynamics exams where a lot matrix calculations have to be carried out. For now I get the job done, but it takes a lot of effort for some not-so-advanced calculations, either because some functions are missing or because of the keyboard layout. I may end up programming a little a bit to do my life easier.
I think that TI Nspire CX CAS would be better suited for my needs, due to the separate character-numeric keyboards, but I was sold for the touch screen of the HP Prime.
I didn't have a chance to hold them in my hand. If I did I may have bought the TI Nspire, who knows ?
However I really like the context help menu.
There are also two things that would make it great, an undo key and an autocomplete feature for the name of the functions.

[cyrille de brébisson]

Hello,

Thanks for your comments.

As stated by Steve, the CAS and the Home view are different beasts.

HP did put on a lot of work to partially integrate them, but this is not 100% possible, and differences will stay.

The CAS is based on xcas, created by Dr Bernard Parrise which you can download and install on your PC. I believe that Most non-complex xcas programs will be compatible between the calculator and the PC version of the cas (assuming that you respect some rules) Bernard, can you chime in here? This is a cool thing as it means that you can create and develop a program on the PC and then move it on the calculator with minimum work.

Now, CAS and home do have different ways of doing things (for good reasons). For example, Home has a programming language that is somewhat consistent with languages like C or Pascal while the CAS language is more of a scripting language (for example, there is no locality of local variables).
Since most of the documentation on Prime relates to Home, this can sometimes be deceiving when doing anything non-trivial.

Anyway, with this in mind, I hope that you have a good time with your Prime and that you enjoy it.

Cyrille

[smp]

Thank you *very* much, Steve and Cyrille, for your concise descriptions of the Prime and how it operates.

I've been watching the questions and answers go by since my arrival here last July, and (for me) this is the first time that I've seen this very nice short description of the Prime as really two different machines in one package, loosely linked.

This is by far the best way for me to think about it, and have an understanding of what is going on.

smp

[std]

Hello again friends.
It's really nice to see that there is an active community with friendly people helping each other. It may sound like a stereotype, but it's not the case in every forum.
I am back again with a question. When creating a new program, when should I check the CAS checkbox in the starting dialog? I am going to write a program using CAS variables and functions, if that helps.
A youtube tutorial that I watched, where CAS was not checked, although it works with expressions containing X variable.
https://youtu.be/A7PQ366FF-g?t=9m

The documentation is so outdated and not of much help. I read somewhere that an up-to-date version is coming, but who knows when...

[Didier Lachieze]

You'll find a very good introduction to CAS programming in this article: HP Prime CAS programming.

More generally jebem is maintaining a great list of documentation materials about the HP Prime here.

[cyrille de brébisson]

Hello,

One aim to strife for is to minimize CAS/Home transitions...
So, it your program is mostly symbolic stuff, stay in CAS as much as you can.
If it is mostly numerical, stay in home as much as you can...

In your program, you can always use the #cas and #end to switch to cas mode (which is what checking the CAS checkbox does).

Cyrille