Calculator Thoughts - Page 1
Forum section: electronics / beginners

author: Cujo
author_rank: Regular Contributor
timestamp: July 01, 2020, 04:54:04 am
content: Would you recommend this calculator: (Casio fx-570ES Plus) for an electronic engineering student?

author: rstofer
author_rank: Super Contributor
timestamp: July 01, 2020, 03:30:40 pm
content: At the low end of cost, it's as good as anything else. The HP Prime and TI-84 seem more modern/appropriate but they are much more costly. They also have libraries and graphing and are much more capable. At the basic calculator end of the spectrum, the Casio is just fine.The graphing features of the Prime or TI-84 may come in handy in school. I also use Desmos.com for graphing and Symbolab.com for solving. When I graduated, we were still using slide rules and the HP35 came out in my senior year. A long time ago...In the end, I'm not going to recommend any calculator that doesn't use Reverse Polish Notation (RPN) as its fundamental way of entering values. In that regard, I would probably go with the HP Prime. I don't find it to be as friendly as the earlier calculators (HP 35, HP 45 and HP 48GX). It does everything, no doubt, but it seems awkward to have to push Blue->Enter to evaluate 5*e1/6The keystrokes SHOULD be 1 Enter 6 / ex5 * as in the HP 48GX. Since that is a common equation in EE, think about how to do it with whatever calculator you choose.For the HP Prime, the keystrokes are 5 * ex1 / 6 Blue Enter, not entirely RPN as I know it but it's ok, just different. The Prime offers Algebraic, Text Book and RPN entry types.The epitome of calculators, in my opinion, is the very old HP 48GX but you probably guessed that.It's pretty easy to get very different opinions on calculators and while I use my HP 48GX every single day, I realize it isn't the only calculator that solves the need. That Casio fx-570ES Plus will do just fine and it is a heck of a lot cheaper. Later on, when you find the Algebraic entry system to be a PITA, remember what I said about RPN.I have the HP Prime and a couple of incantations of the TI-84 but I actually USE the HP 48GXHave you thought about using the Free42 cell phone app? It's a nice HP 42 work-alike but it doesn't do graphing.

author: emece67
author_rank: Frequent Contributor
timestamp: July 01, 2020, 03:36:41 pm
content: .

author: rstofer
author_rank: Super Contributor
timestamp: July 01, 2020, 03:54:01 pm
content: Back to Free42, I have it on my Android cell phone and my iPad. I like the "big button" layout on the iPad. Very nice for an old man! Try this out before spending any money! Assuming your instructors will allow a cell phone in the room. Many want them shut off. I guess you could silence the phone and still use it as a calculator.The HP42 was a very popular calculator.There may be restrictions on which types of calculators can be used in which courses. Some instructors will only allow low end calculators that have no Computer Algebra System (CAS) and that leads to the use of very low end calculators. In these classes, a calculator may not even be necessary. Basically, they want YOU to evaluate the integral, not the calculator. Fair enough...In the big leagues, it's "Run what you brung!" - anything is acceptable. At that point, graphing calculators may make sense.I gave away my HP 35S and I shouldn't have done that! It is a reincarnation of the original HP 35 that came out in my senior year of college. It uses an LCD display instead of 7 segment but is otherwise identical. It is a terrific calculator that is only about 3x the cost of the Casio. Like many things, the original was perfect, everything else is something else. Except for the HP 48GX which is the epitome of calculators.

author: rstofer
author_rank: Super Contributor
timestamp: July 01, 2020, 04:10:38 pm
content: And bonus points if the calculator uses replaceable batteries. There's nothing quite as fun as having a calculator die during a quiz. With a battery calculator you just grab the spare batteries out of your backpack. You did put extra batteries in your backpack, right?Maybe one of those recharging battery packs would make sense. So would recharging the calculator the night before the quiz.A spare calculator makes sense as well. That bit of insight comes from 30+ years of working in the field!

author: Howardlong
author_rank: Super Contributor
timestamp: July 01, 2020, 04:43:25 pm
content: If you're a student, use whatever is recommended, it won't be unusual for them to structure courses around a given calculator's functionality.Keep in mind though that the use case for a calculator is very different between a student and real life working. And with that here's my waffle...As a working engineer, I use two calculators on a daily basis, the RPN HP-15C or infix FX-991D (almost identical to FX-570AD/CD, FX-100D, & FX-115D). Both these calculators benefit from persistent engineering display mode and direct keyboard access to commonly used engineering math functions without having to perpetually fish around menus or look stuff up in manual or online. FX-991D gets extra points for offering solar as well as battery. No VPAM/CAS nonsense.I've tried to get used to CAS/VPAM or whatever the lingua franca is these days, but I find it too fiddly to mess around with given the limitations of the keyboard. The use case for calculators in a work context are for quick, short calculations. Much more than that, it's done on a computer. Any numeric or analytic solving I do old school with the computer and/or pen and paper, although it is a marvel what these calculators can do.A few years ago I tried really hard to get on with the HP Prime, but realised that despite the amazing functionality it offers (e.g. matlab style complex, matrix and vector calculations), it is of limited use practically in a work scenario purely because of the limited user interface. I just found the UI, particularly the keyboard and menus, just got in the way. The PC emulated version is actually much better than the real thing because you have a proper keyboard.Much more recently I picked up a Casio FX-CG50, and it has similar limitations to the Prime for real work use. Software-wise it's not as fancy as the Prime, but it does offer micro Python which was the reason I got it... and then left in a drawer ever since.On the RPN side although I have a number of more modern RPN calculators like the HP-32Sii, HP-35S and WP-34S, for me nothing beats the the straightforwardness of the HP-15C, or the HP-11C for that matter, for quick calculations (I don't really have any practical use for any of the functionality on the 15C that isn't on the 11C, I'd be heading to the computer if I did).For system programming the HP-16C can be handy occasionally, particularly if you're manipulating stuff at the bit level, for example I was writing an OLED graphics driver the other day, and it was invaluable for dry running my code. I've never found a system programmer's calculator as good or as useful as the HP-16C. The most obvious limitation is the lack of shift left or right N bits, but that's easily solvable in a couple of short keystroke programs.

author: rstofer
author_rank: Super Contributor
timestamp: July 01, 2020, 05:26:28 pm
content: Quote from: Howardlong on July 01, 2020, 04:43:25 pmIndeed! Get very comfortable with MATLAB (student license available) or the no-cost workalike GNU Octave. Anything beyond the simply trivial will probably be solved with these tools. Demos.com and Symbolab.com are great for students but looking out at industrial applications, MATLAB is the way to go. wxMaxima is also useful as is Mathematica but my favorite will remain MATLAB.It tuurns out, MATLAB is a required course at my grandson's university. It will be the tool of choice for Differential Equations and Linear Algebra. You just can't get along without knowing how to use this tool.Then there is Fortran... Actually, the libraries being created for Python make that language compelling.

author: rstofer
author_rank: Super Contributor
timestamp: July 01, 2020, 05:38:26 pm
content: That Casio has some nice advanced features like integration and differentiation. It takes a bit of quality time with the manual but it's all given. The key strokes seem awkward but that's because the book isn't the calculator. In real life, it may be more intuitive.For the cost, go for it! There is plenty of time later to think about other methods and calculators.

author: rstofer
author_rank: Super Contributor
timestamp: July 01, 2020, 05:43:19 pm
content: Is the FX-991 an upgrade?https://www.amazon.com/CASIO-Scientific-Calculator-FX-991ESPLUS/dp/B0034BAQS8For that price I think I'll pick one up to play with. The integration and differentiation alone make it worth exploring.

author: Byonnem
author_rank: Newbie
timestamp: July 01, 2020, 06:16:49 pm
content: As an EE student myself, I really like the TI36x Pro.. TI84 is often not allowed at exams, but TI36x pro is not an issue (in my experience), but check your local rules.MATLAB is a (very nice) tool for other occasions but is not a substitute for a calculator.M.D.S

author: Rick Law
author_rank: Super Contributor
timestamp: July 01, 2020, 06:29:34 pm
content: As a student, you should also consider if that particular calculator is approved for use during a test/exams.It would be an extra level of difficulty if you have switch to an unfamiliar calculator during a test because your regular one is not approved for use during tests.

author: emece67
author_rank: Frequent Contributor
timestamp: July 01, 2020, 06:40:36 pm
content: .

author: mathsquid
author_rank: Frequent Contributor
timestamp: July 01, 2020, 06:53:35 pm
content: Yes. I would recommend that calculator. It looks a lot like the fx-115es, which is great.With one exception, I tell my students to get a good scientific calculator, and to use desmos or octave-online.com for graphing and matrices. The exception is for linear algebra classes, where they need to be able to do RREF during tests.I really wish that casio or TI would make a scientific calculator in the $20 range that would do RREF for matrices up to say 5x7. I'd never recommend a graphing calculator again.

author: capt bullshot
author_rank: Super Contributor
timestamp: July 01, 2020, 07:12:15 pm
content: I'd second the recommendation, anyway another "important" feature of a good all-purpose students and engineers calculator is the "base-n" capability that allows you to convert numbers betweeen decimal, binary and hex notation, and do logical operations. You'll find that handy if you get your hands on digital and microcontroller stuff.

author: Rick Law
author_rank: Super Contributor
timestamp: July 01, 2020, 07:20:10 pm
content: One more thought -my opinion is, RPN is a better choice if you are a techie. Your interest in EE said likely you are.This is my journey, but you may found the same benefit as I did.I leaned RPN with HP35. It was confusing at the start, but once I got into that mode of thinking, It became natural to me. I switched over to a TI programmable for its lower cost. I found the TI (non-RPN) more difficult to use than an RPN and very quickly switched back to HP. After that, I never look back.As a Physics major in 1970's, I had to take some programming courses.Assembler used to be the killer for many C.S. want-to-be's.After taking a FORTRAN course, I self-taught myself 8080 assembler. It was actually a no brainier for me. I credit most of that to RPN.RPN gets me to think of doing arithmetic in a way very compatible with how a CPU works.Of course, opinion is like arse-hole, everybody has one and some stinks to high heaven. But hopefully, this opinion of mine is beneficial to you.

author: rstofer
author_rank: Super Contributor
timestamp: July 01, 2020, 08:24:08 pm
content: RREF exists on the TI-84 series but it's closer to $60...https://youtu.be/e8mDRCIRbJUI bought one of the TI-84 Plus calculators a couple of years ago when my grandson and I were evaluating them for his use in college. I have never actually used it. I am impressed! There are some great tutorial videos on YouTube. It was the recommended calculator for one of his earlier classes.Unfortunately, the TI-84 Plus is a good deal more than $20. Still, when compared to tuition and text books, a$60$100 calculator probably doesn't cost as much as the parking pass. Note: I got the price way wrong! Furthermore, it seems like the basic TI-84 Plus may be scarce and replaced by the TI-84 Plus CE which is about $120 at Amazon. That's getting pricey!Extra points because it uses replaceable batteries!ETA: The TI-84 Plus CE does NOT have replaceable batteries but it is slimmer and has a more regular button layout. It's a real attractive calculator.The CE has a color display that is bright and crisp. It is about $120 so clearly much more than the Casio.

author: rstofer
author_rank: Super Contributor
timestamp: July 01, 2020, 09:08:58 pm
content: Playing with my TI-84 Plus CE for a moment, I did an RREF on a 6x7 augmented matrix and it is practically instantaneous.I have the white version of the calculator and the legends are easy to read. This isn't always the case with black keyboards.For those playing along at home, here is the MATLAB code and the results:Code:% A football stadium has a capacity of 100,000 attendees% Ticket prices:% Student = $25% Alumni = $40% Faculty = $60% Public = $70% Veterans = $32% Guests = $ 0% A full capacity game netted $4,897,000% Let S = number of students, A = number of alumni, F = number of faculty% P = number of public, V = number of veterans, G = number of guests% S A F P V G = valueM = [ 1 1 1 1 1 1 100000; ... % total number of attendees25 40 60 70 32 0 4897000; ... % total revenue0 1 -1 0 0 0 11000; ... % 11000 more alumni than faculty0 1 0 1 -10 0 0; ... % public + alumni = 10 * veterans-1 1 1 0 0 0 0; ... % alumni + faculty = students1 0 1 0 -4 -4 0]; % faculty + students = 4 (guests + veterans)A = M(:,1:6); % extract 6x6 matrixB = M(:,7); % extract value column vectorP = M(2,1:6); % ticket price by attendee typeR = inv(A)*B; % compute number of attendees by typeT = sum(R); % check total attendees = 100,000 CHECKU = P*R; % total revenue = 4,897,000 CHECKV = R'.*P; % revenue by attendee type - transpose R from 6x1 to 1x6% then do element by element multiplication%% fancy output, all previous default output semicoloned%label = {'Students' 'Alumni' 'Faculty' 'Public' 'Veterans' 'Guests'};for i = 1:6fprintf('%-8s%7d @ %2d = %7d\n',string(label(i)),...round(R(i)),...M(2,i),...round(V(i)))endfprintf('\nTotals %6d %8d\n',round(T), round(U))Code:Students 25000 @ 25 = 625000Alumni 18000 @ 40 = 720000Faculty 7000 @ 60 = 420000Public 42000 @ 70 = 2940000Veterans 6000 @ 32 = 192000Guests 2000 @ 0 = 0Totals 100000 4897000

author: Howardlong
author_rank: Super Contributor
timestamp: July 01, 2020, 10:21:41 pm
content: Quote from: emece67 on July 01, 2020, 06:40:36 pmI have the official 15C and wp-34s apps on my phone. The emulations are accurate, but the touch screen keyboard is a bad experience. It's a perennial problem with touch screen UIs, not just calculators. There's a similar problem with calculators on the computer too.

author: Shock
author_rank: Super Contributor
timestamp: July 01, 2020, 11:20:28 pm
content: As with what others have mentioned you go with what is approved and recommended for the course and exams and if you have different subjects try for cohesion if at all possible.

author: wizard69
author_rank: Super Contributor
timestamp: July 02, 2020, 12:58:29 am
content: On my iPhone I have "i42CX+, paid for it years ago and it is likely the only app on my phone worth the money!!! There are however dozens of calculators available on the app store.Apps are not perfect, for example glass screens can not replace real keys like the nicer HP's have. However since the majority of my use is in the field, making a quick calculation that doesn't really matter. Also it pays to have an app that has a history function or as some of them call it a paper tape so you can review what you just did. In the end if my job required more use of a calculator I'd get a real one.As other have pointed out there isn't a lot of value in calculators these days. So don't be surprised if the only programming use you get out of a pocket calculator happens in a few classes in school. There are likely exceptions to this but a laptop is just far more flexible. In some organizations the first thing engineers turn to is a spreadsheet app. I'm not saying this is a good thing just that it is that way in some organizations. You will have to become familiar with spreadsheets anyways, to interface with management, so you will get a payoff learning to use this sort of software. What the professors think about this usage probably isn't good and I would ten to agree but it is reality.Your classes will be built around one or more software packages and possibly a calculator so when it comes right down to it we can't give you any advice. So check with the programs leadership / professors or anyplace else you might find the answer. MatLab is used in many programs but just as many are moving away from Matlab to things like Python, or Jupyter Notebook. Jupyter is not well known but it basically provides a web based interface to Python programs (gross over simplification). I'm not up on the university scene but Jupyter is being developed open source buy a team of colleges {Just looked in, look like corporate America is taking over} from what i can see so there is the potential that you college is working it into an engineering program - check here:https://jupyter.org/In the end it really comes down to what your college expects you to use. I'd would be shocked if programmable calculators are a thing anymore in Engineering courses.

author: knapik
author_rank: Regular Contributor
timestamp: July 02, 2020, 01:17:57 am
content: Just remember, you'll need 2 calculators. One scientific one without any sort of text storage and a CAS one depending on your exams.

author: Howardlong
author_rank: Super Contributor
timestamp: July 02, 2020, 06:59:37 am
content: Quote from: knapik on July 02, 2020, 01:17:57 amAny self-respecting engineer of a certain vintage "needs" at least a dozen calculators, preferably far more.

author: jpb
author_rank: Super Contributor
timestamp: July 02, 2020, 10:26:08 am
content: Quote from: Howardlong on July 02, 2020, 06:59:37 amI second this view. I also deeply regret the passing of the golden age of HP calculators and their amazing keys - the modern ones are just not the same.The SwissMicros ones are tempting:https://www.swissmicros.com/dm42.phpbut the one review I read stated that the keys aren't that great (OK but not like the original hp).Dave reviewed it a while back and there have been a few threads/mentions on these forums.

author: frogg
author_rank: Regular Contributor
timestamp: July 02, 2020, 12:56:43 pm
content: Quote from: emece67 on July 01, 2020, 03:36:41 pmAs someone who owns two HP48's, I think this is exaggeration and I disagree totally.I made it through as an EE student just fine without an HP48. I couldn't even afford an HP48 until one was given to me as a gift after my first job interview out of undergrad."Overall suitability"? What does that mean?

author: rstofer
author_rank: Super Contributor
timestamp: July 02, 2020, 02:57:17 pm
content: Sure, I made it through EE school with a slide rule but I wouldn't recommend anyone else do it! RPN calculators are getting a little thin on the ground and I have had the HP 48GX for nearly 30 years. Back then they were EXPENSIVE but I wanted it for its programming features. I wrote an entire Celestial Navigation suite just for giggles. Interesting...I like RPN entry but, like anything else, I can adapt. The problem today is that there are some terrific calculators. One would have to divide the universe into graphing and non-graphing and then CAS versus non-CAS and so on. I was playing with my TI-84 Plus CE yesterday and it seems like a very nice calculator. There are some key combinations that are regrettable (like having EE as a 2nd combination) but I could get by with it. I would complain every time I had to use EE but at least my complaint would be focused. The screen with backlight make it a lot easier to see for an old man.I have a variety of calculators but I use the HP 48GX because it is siting on the table next to this laptop.Some time today I'll receive the Casio FX-991ES PLUS which seems to be an upgrade of the OP's FX570ES PLUS and I'll get a chance to see what it does. From the manual, it has nowhere near the capability of the TI-84 Plus CE in Matrix operations. That's unfortunate because we tend to use a lot of simultaneous equations in EE. Kirchoff is one area and Statics (usually a required course) is another. Particularly for truss problems.The TI-84 Plus CE has a form of RPN entry so I'm mostly ok with it. It will never be the HP 48GX in terms of ease of use but it has a lot more features and they are a lot easier to use. The screen brightness and resolution have a lot to do with that. Note that the non-CE version doesn't have the improved screen.

author: Howardlong
author_rank: Super Contributor
timestamp: July 02, 2020, 03:36:37 pm
content: Quote from: rstofer on July 02, 2020, 02:57:17 pmI believe that to all intents and purposes they're the same device, except that the 991 has solar plus button cell backup, rather than just the AAA cell of the 570, making the 991 slightly thinner as a result.

author: rstofer
author_rank: Super Contributor
timestamp: July 03, 2020, 03:28:09 pm
content: I bought the FX-991ES Plus version of the OP's calculator. Yes, it does have solar capability. Apparently it also has 417 functions and Text Book entry. I clearly didn't try them all...It's a pretty neat little calculator and it has a lot of functions brought out to keys like factorial and cube root.It will take some time with the instruction manual and that is going to take younger eyes than mine. The printed font is Tiny Extra Midget. There is an downloadable PDF version that will be a lot more readable.There is some useful information inside the cover. I found the "Restoring Mode Default Settings" to be most helpful after I got the calculator jammed up.The matrix handling capability is pretty pathetic. AFAICT, it will only handle up to 3x3.For the money, this is a pretty nice calculator.https://www.amazon.com/CASIO-Scientific-Calculator-FX-991ESPLUS/dp/B0034BAQS8It's pretty clear that the high dollar calculators will be more capable but with non-calculator tools like MATLAB (or GNU Octave) on every laptop, I wonder just how much high end calculation is actually being done on a calculator these days. The 6x7 RREF example I gave above is actually easier to do on a calculator than with MATLAB but MATLAB scripts document the solution. It goes both ways, I guess.For quick calculations of simple expressions, this calculator will get it done. So will just about any other scientific calculator. This one has the advantage of an extremely low cost.It will not replace my HP 48GX or my TI-84 Plus CE.