[HP Prime] - EXP() or e - Printable Version +- HP Forums (https://archived.hpcalc.org/museumforum) +-- Forum: HP Museum Forums (https://archived.hpcalc.org/museumforum/forum-1.html) +--- Forum: Old HP Forum Archives (https://archived.hpcalc.org/museumforum/forum-2.html) +--- Thread: [HP Prime] - EXP() or e (/thread-248727.html) |
[HP Prime] - EXP() or e - Jean-Michel - 08-23-2013 Hello all
Please forgive me if what follows have already been pointed out here before. Edited: 23 Aug 2013, 5:11 p.m.
Re: [HP Prime] - EXP() or e - Marcus von Cube, Germany - 08-23-2013 It locks like the CAS environment is quite distinct from the home screen. In the latter, e^ is displayed as an exponential and not as EXP(). The same key in the CAS screen is shown as EXP().
Re: [HP Prime] - EXP() or e - Tim Wessman - 08-23-2013 From the calculator's perspective, EXP() and e^ are two different things. One is a much less accurate power function. Internally in HOME, e^ is rewritten internally to EXP, but still displays as e^. In the CAS side though, it isn't so simple. Basically, all the complaints people have regarding display of things, or complaints about less strict handling of vectors/matrices/lists, all go away completely in the home screen. It is purely is the CAS screen where these strange things happen and stems directly from the decisions made by the CAS author. Why haven't all those things been resolved? They just take time. Many other higher priority things were needed for a first release. I've heard from quite a few people how they are extremely impressed with Prime despite having initial misgivings. Usually the main two things mentioned are the "vocal" complaints they saw from a small minority, and then the fact that is isn't exactly like the 50g and so they weren't quite sure what to expect. There will of course be plenty who disregard/dislike/don't purchase for on reason or another - as is their right to do so. As a side note, the 50g does this exact thing. e^ gets converted to EXP internally and any time you look at an algebraic object it shows up. It is purely a cosmetic thing there as well. I haven't seen outrage for years about that though... :-) Would I have liked to have the time needed to polish everything absolutely first? Sure. Reality just doesn't always cooperate. I would point out though that people (not you, just a comment in general) who immediately dismiss prime as a "student only" machine trying to be an Nspire clone or something should take a closer look at it. Even a casual browse through the matrix menu should demonstrate that isn't the case. A student will be able to easily learn it, use it, but, more importantly, *continue* to use it in higher ed or beyond. There is plenty of growth built in. It isn't designed to be just a "teaching tool" exclusively like the nspire so obviously is. TW
Edited: 23 Aug 2013, 5:45 p.m.
Re: [HP Prime] - EXP() or e - Jean-Michel - 08-23-2013 Hello Tim
I thank you for your answer. I will wait for next release(s) to have this minor problem fixed. I do understand this is purely cosmetic and that other more important improvements may be done before. Re: [HP Prime] - EXP() or e - parisse - 08-24-2013 Quote:In giac/xcas, e is parsed as exp(1) and exp(1)^x is auto-simplified as exp(x). Therefore EXP(x) and e^x are equivalent.
Quote:In fact, when I started the giac project, I decided *not* to make a difference between lists and vectors or lists of lists of the same size and matrices, because of my previous experience with the HP48 Erable and HP49 projects. It was so annoying to have to call array to list to list conversions, and there was no reason to do that since the container are exactly the same. In addition, I have added the possibility to handle univariate polynomials directly in list form, i.e. extend PROOT/POLYROOT and POLYCOEF to more arithmetic operations. That's why for example [1,2]+3 returns [1,5]: [1,2] is considered as the list of coefficients of the polynomial x+2 (always descending order), you add 3 you get x+5, represented as poly1[1,5]. You can also multiply polynomials like that, take quotient and remainder with quo/rem, find Bezout polynomials with abcuv or egcd, and so on. Coefficients may belong to the rationals, but also to a finite field (Z/pZ with p prime using % on giac or %% on Prime or even a Galois Field extension, command GF). All the operations that are sometimes commented here as strange have always a meaning. Sometimes there may be two or more ways to interpret an operation on lists, then you can select the right operation by replacing the opening [ of the list with poly1[ or matrix[ or set[ or seq[ or just call another operator (like .+ .* ...) I can understand that people used to another calculator find it disturbing, and I'm ok to add a few warnings (e.g. for inverting a list of lists elementwise vs inverting a matrix) but I don't believe it would be a good idea to clone the HP49/50 or TI nspire CAS behavior vs lists/vectors because that would probably require a lot of work to add strict checks (and would require a lot more conversions command calls by the users after). I have never received complains about that by Xcas users (which is now used in many highschools in France as a CAS), therefore I really believe that these complains are mainly caused by old habits, they won't affect new users. It's in my view much more important to improve the CAS itself (like improve the regroup function for auto-simplification, or extend/speedup some commands).
Quote:giac is certainly not a nspire clone, it's designed to be a competitor to major CAS like maple. There are a lot more advanced math functions that (unless I'm mistaken) are not available on the TI nspire CAS like (not limited to) - integer arithmetic (extended gcd, chinese remainder, modular computation, quadratic sieve for integer factorization) - polynomial arithmetic (extended gcd, resultant, Groebner basis) also working on Z/pZ and finite fields - exact linear algebra (kernel, Jordan normal form, symbolic matrix power, quadratic form reduction) - some symbolic stuff like recurrence relation solver (rsolve command), or special functions like cosine/sine/exponential integral, or Laplace/inverse Laplace transform giac is clearly not a highschool/first University year only CAS, you can still use it for computations during 3rd/4th year of University or later... This extends to the Prime CAS of course... Re: [HP Prime] - EXP() or e - Pal G. - 08-25-2013 Welcome to the HP Museum forum. Thank you for your contribution to HP calculators, and a myriad of other apps that make use of your project.
Best regards,
Re: [HP Prime] - EXP() or e - deachp - 08-27-2013 Thanks Tim Wessman and Bernard Parisse for your clarification.
Tim Wessman:
Bernard Parisse: |