chad@ucscb.UCSC.EDU (darknight) (02/22/90)
I am looking into buying a Hi-Tech, Super-Dooper, Ultra-Cool-Neeto, Programmable/Graphing calculator... The three models I'm currently looking at (in no particular order) are the Sharp EL-5200, the Casio FX-8000G, and the Hewlett-Packard HP-28s. I want to know if anyone has any opinions and/or recommendations for any of these. The Hewlett-Packard (which I've seen) is the most expensive, but it has the smallest (physically) display screen. The Sharp is the cheapest. Some specific things, besides general opinion, that I want to know are: 1) What are the resolutions (pixels) of each of these calculators? 2) What are the memory capacities, and function capabilities of each of these calculators? 3) What are the graphing capabilities (can it pan, zoom, slice, dice, etc.)? 4) What are the programming features? 5) What problems does it have (size, weight, battery limits, exploding keys, etc.)? 6) Is there anything else better? I'm looking to buy the one with the best functionality/cost ratio (although I would have lots of fun fooling around with the HP's programming, so that does give it a plus). If you mail me, I will summarize the responses (or you can just post your opinion). Thanx in advance. -- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ INTERNET: chad@slugmail.ucsc.edu Chad 'The_Walrus' Netzer->AmigaManiac++ ------====== "Life is a Strange Attractor." ======-------
jln@portia.Stanford.EDU (Jared Nedzel) (02/27/90)
In article <6816@ucdavis.ucdavis.edu> chad@ucscb.UCSC.EDU (darknight) writes: } } I am looking into buying a Hi-Tech, Super-Dooper, }Ultra-Cool-Neeto, Programmable/Graphing calculator... The three models }I'm currently looking at (in no particular order) are the Sharp EL-5200, }the Casio FX-8000G, and the Hewlett-Packard HP-28s. I want to know if }anyone has any opinions and/or recommendations for any of these. } The Hewlett-Packard (which I've seen) is the most expensive, but }it has the smallest (physically) display screen. The Sharp is the }cheapest. Another thing to consider is the basic notation of the calculator. Most calculators use an algebraic notation; that is, if you want to calculate 7 + 3, you type 7, then +, then 3, then =. Hewlett-Packard calculators use RPN (reverse polish notation), in which you type 7, enter, 3, +. The HP thus gives you a stack which you operate on. The notation is sort of a post-fix notation (i.e., the "opposite" of Lisp infix notation). A discussion of which notation is better often leads to religious wars (complete with excommunication). I'm an RPN believer, so an algebraic notation calculator quickly reduces me to a blithering idiot. Algebraic devotees often seem to find RPN incomprehensible. I suggest you make a choice and stick with it. Another important issue is the ergonomic design of the calculator. I've had three HPs: HP-65, HP-41c, HP-12c. I have found the '65 and '41 to have wonderful buttons: just the right combination of travel, click, resistance (the '12c wasn't quite as nice). You know when you've pressed a button on an HP. (I seem to recall that HP spent over $1M designing the buttons circa '78, when a million was really a million.) I'm not familiar with the other calculators in your list, but it has generally been my impression that no other company had matched HPs for feel. They also don't match HP for price :-(. But if you use your calculator a lot, it might be worth it for you. }INTERNET: chad@slugmail.ucsc.edu Chad 'The_Walrus' Netzer-}AmigaManiac++ -- Jared L. Nedzel --------------------------------------------------------------------- e-mail: nedzel@cive.stanford.edu jln@portia.stanford.edu
frankw@hpcvra.CV.HP.COM (Frank Wales) (02/27/90)
This is a *long* article with many opinions from nearly two decades of using calculators for work and play. It doesn't try to answer the questions asked so much as give more general advice about choosing the best calculator for your needs. If you just want columns of numbers, lined up for easy comparison shopping, read another article. [Note: Ignore the address -- I am not an HP employee.] In some article chad@ucscb.UCSC.EDU (darknight) writes: > I am looking into buying a Hi-Tech, Super-Dooper, >Ultra-Cool-Neeto, Programmable/Graphing calculator... What do you actually want it for? a) getting the job done b) playing with c) impressing people who know about calculators d) impressing people who don't know about calculators You can choose any or all of these, but where you place the emphasis has a significant effect on which machine you should buy. If you place the emphasis on a), buy Hewlett-Packard. If you place it on b), buy Hewlett-Packard. If you place it on c), you *must* buy Hewlett-Packard. If you place it on d), who cares? >The three models I'm currently looking at (in no particular order) are >the Sharp EL-5200, the Casio FX-8000G, and the Hewlett-Packard HP-28s. >I want to know if anyone has any opinions and/or recommendations for any >of these. Well ... > The Hewlett-Packard (which I've seen) is the most expensive, but >it has the smallest (physically) display screen. Putting a bigger display on a calculator is like putting a bigger dashboard in a car. It's easy for the maker to do, but hard to make good use of. It has a side-effect that the marketing types then have BIGGER NUMBERS to put in their brochures, in the hope that potential buyers will be more interested in the number of PIXELS (technical term there) than in whether the machine actually gets the right answers. Other than for use in plotting neat curves, most big display calculators just use the bigger display like a garbage dump for calculations, leaving them lying around in the slight hope that they may be useful again in the near future, a bit like old TV actors at the Academy Awards. Needless to say, the HP machines are an exception here. Or look at the keyboards: too many top-end machines look like the aftermath of a sign-writer's booze-up, with 400 billion ennsy-weensy legends, and more modes than you've had hot dinners. And you can bet that *somewhere* in there is a set of summation values to remain backwards-compatible (sic) with the machines they released in the 1970s. No doubt some people like this kind of keyboard clutter, but I'm not among them. In general, calculators don't have enough keys, but the solutions which HP have come up with (redefinable keyboards, menus, softkeys) are harder to implement than just MORE COLOURS and MORE SHIFTS (2nd, 3rd, INV, Alt, ALPHA, Mode, Shift, Alg, Op, Gag, Barf) because they represent a slightly different approach to the problem. Instead of saying: "How can we get more stuff on the keyboard?" they say: "How can we help the User *manage* the functions we put at his or her disposal?" Having said that, in the numbers department, the HP-28S has MORE KEYS than the competition (although only one measly shift key). > Some specific things, besides general opinion, that I want to >know are: >1) What are the resolutions (pixels) of each of these calculators? As I hope I've shown, the use a machine makes of its display is far more important that the number of dots in it. And don't succumb to the false logic that: because: "it has a bigger display, therefore it *can* do everything a machine with a smaller display can" this implies that: "it *must* do everything a machine with a smaller display can" or (even worse): "it does everything *better* than machine with a smaller display" >2) What are the memory capacities, and function capabilities of each of these calculators? Memory is probably one of the most important fundamental features concerning a choice of calculators; another is battery life. Speed is a third. Calculators *never* have enough memory, they rarely run fast enough, and they require to be fed just too often. The ideal machine remembers everything, answers immediately and runs off the static electricity in your underwear. This machine doesn't exist, and never will, but manufacturers are striving to make you think that they have the next best thing. Calculator makers don't make it easy for you to decide how much useable memory a machine has, because they speak interchangably about bytes, steps, lines, registers, and other things. Also, how profligate a particular machine is in storing things like program lines can have a big effect on the meaning of any quoted figures. You can't even trust things like how many steps can be fitted into memory, because some machines have a richer selection of programming constructs than others, and so the "same" problem might use up twice as many steps/bytes/lines on one machine than another. Certain things you can usually assume are that: within a product line, memory consumption will be similar; across all calculators in this area, the amount of memory used to store numbers will be the same (usually 8 bytes these days); the more flexible the management of memory is in the machine, the less likely you are to hit a memory wall. For example, being able to trade off program space for data storage is simple and common these days; if a machine can't to it, it's in the calculator dark ages. Having a lot of flexibility here is an indication that the people who designed the machine *cared* about making the best use of the feeble amount of memory they decided to lumber you with -- this is a good sign. You should be wary of machines whose descriptions say: "allows up to 10 programs in the machine at once" [why an explicit limit? [especially if the machine has a pile of memory]] "allows storage of up to 43 numbers at once" [why an explicit limit? [and why such a weird number?]] "9 return levels, 6 flags, 18 levels of parentheses" [why explicit limits? [sound familiar yet?]] "has 3,481 bytes of memory..." [they're rooting around, trying to find every last byte in there] "...of which 2,971 are available to the user" [uh-oh, they're *really* desperate, and they're hoping you'll compare machines using the bigger number, which is why they put it in the brochure first] "5 conditional tests, 4 flag operations, 3 types of label, 2 data classes and a partridge in a pear tree" [ignore the numbers of things: how many ways it can do something is less important that whether it can do it at all -- look for capability first, quantity second] Speed is something very dear to the hearts of calculator weenies: "my Sharsio DX1234 can run an empty loop 17.222% faster than your TP-99 II." Very good. But does get the *right* *answer* 17.222% faster, or does it take just as long to compute trig, stats and other complicated stuff? Try using this loop to find the cosine of 482 degrees (what? it's not negative?), find 169! (what? it doesn't go that high?), or raise -2.5 to the power of -4.5 (what? it doesn't return complex results? how about -2.5^(-4)? no?). And find out how consistent the calculators are. Try this: + set the machine to display the maximum precision it can + type in 2 + take the square root, and write down the answer as it appears in the display (1.4142...) + square that again, and subtract 2 from it --> answer A + type in the number you wrote down, square that, and subtract 2 from it --> answer B On many calculators, A is not the same as B. This is because many calculators *hide* things from you (so-called guard digits). You can find them out, but you have to do something awkward like subtracting the contents of the display from the number in the display, and seeing if there's anything else left over. Most calculations you'll ever perform don't require anything like the precision used by the average calculator, and so a second thing, consistency of operation, becomes more important (if only because it's noticeable, like in the example above). If you believe that consistency is more important that unnecessary accuracy, you'll be pleased with an HP machine. Battery life relates to power consumption and the number of batteries in the machine. These days, calculators consume power even when they're "off"; look for a statement about battery life which tells you how long you'll go between changing batteries, of course. But also, find out how much warning the calculator gives you of failing batteries -- a good machine gives you days or weeks of warning, not hours or minutes. And look in the manual at the section on changing the batteries (it does have one, doesn't it?) to see if they tell you how long you can take to change them *without* losing the memory of the machine; you shouldn't need the dexterity of a plastic surgeon and the limbs of an octopus to do it in time. >3) What are the graphing capabilities (can it pan, zoom, slice, >dice, etc.)? What, you want to run X on it? >4) What are the programming features? Can you *name* things, like programs and variables, instead of just giving them numbers? Can it stand recursion? Can you write programs which behave like the built-in functions, or are there parts of the machine's obvious functionality forbidden to you? Many makers of an up-market machine will shovel some semi-extended BASIC into it, crippling it at birth. Regardless of their merits elsewhere, BASIC and its siblings were never designed as the basis for such machines. The programming language of any machine should act as a logical extension of the keyboard calculation mode, and should not be some orthogonal wart grafted on the side (sick). So the choice of calculation logic system dictates fundamental aspects of the rest of the machine's behaviour. There are two choices of logic system these days in the more-than-four-function calculator world: RPN (made by HP), and EverythingElse, also loosely known as "algebraic logic", or "The Wrong Choice". RPN is simple, consistent, predictable, allows easy recovery from errors, and is confidence-building. So-called algebraic systems are rarely any of these. And chances are, you use RPN all the time anyway, but didn't notice. Try the following logic system taste-test: Q if you press the wrong key by mistake, can you just cancel the effects of that key, or is the calculation you were working on trashed? A if it is, you're not using an RPN machine Q when you solve a complicated problem, does your calculator display the intermediate results as you go along, giving you confidence about the progress of the calculation, or does it keep you in suspense until you press the '=' key, and then *WHAM* you get surprised by a funny-looking number? A if you *are* surprised, you're not using an RPN machine Q if you're typing in a calculation on the fly, and discover that you've got the intermediate results in the wrong order, can you change the order without aborting the calculation? A if you can't, you're not using an RPN machine Q how do you work out sin(35) on your machine? A if you answered "type in 35, then press the SIN key" you're using RPN, regardless of what the maker of the machine says you're using It was once argued that algebraic machines were better if the entire calculation was known ahead of time, the "Enter it as you would write it down" school of thought. The annoying corollary "Type it in perfectly or woe betide you and your results" aside, how many machines accept things *as*you*write*them*down*? I don't happen to write things down full of parentheses or multiplication and division symbols, nor do I write references to log or trig functions like a programming language would require me to. And what if I start bringing calculus or summations in? Like it or not, all non-trivial calculations involve some translation from MyWayOfDoingIt to TheCalculator'sWayOfDoingIt. Having a way of reinforcing the translation process by being able to see the calculation proceed in a direction I'm happy with, and being able to recover from keying and other entry errors without having to start again are very important to me, and if they are important to you, RPN is The Right Choice. >5) What problems does it have (size, weight, battery limits, >exploding keys, etc.)? Can you carry it around, or will it be tied to a desk? Can you buy the batteries for it everywhere you like to buy batteries, or must you negotiate with some light bulb salesman long-distance? Does it seem durable, or are you happy with the risk that if you sit on it, drop it or leave it in checked-in luggage, you'll be buying another one tomorrow? Can you read the display in unhelpful lighting situations (like too many stray reflections)? Does the keyboard *feel* good under your fingers, or are the buttons tacky-looking or wobbly rubber with flaky printing (go ahead, scrape a keytop)? Do you get a case with it, or is the box it comes in the case? Do you get a comprehensive, comprehensible manual, and maybe a pocket guide thrown in, or just a wadge of dense prose with no index? Is there a customer support number in the manual that you can call for help or advice? Can you buy books with potted answers to common problems, or are you on your own? >I'm looking to buy the one with the best functionality/cost ratio >(although I would have lots of fun fooling around with the HP's >programming, so that does give it a plus). The ultimate goal here is to get a machine that you won't regret having bought in a year's time. For my money, there is nothing better than an HP RPN machine. I hope that this article is of use in helping you to see why I believe that, and in deciding whether you should believe it too. >6) Is there anything else better? Perhaps one of the more interesting things to note is that comp.sys.handhelds is drowned out by HP-28S Users exchanging programs, tips and information. Why should this be? The following scenarios present themselves: 1) the owners of these machines like them, enjoy using them, and want to share their enjoyment with the world 2) the friends of HP run around getting people to post things about HP calculators, to give the impression of 1) 3) the machines are so damn lousy that people desperately need help in using them, since they can't ever find another sucker to buy them second-hand 4) the enemies of HP run around getting people to post things about HP calculators, to give the impression of 3) To resolve this question, read the newsgroup; my money's on 1). -- Frank Wales, Guest of HP Corvallis, [frank@zen.co.uk||frankw@hpcvdq.cv.hp.com] Zengrange Ltd., Greenfield Rd., LEEDS, England, LS9 8DB. (+44) 532 489048 x217
sean@ms.uky.edu (Sean Casey) (02/27/90)
chad@ucscb.UCSC.EDU (darknight) writes: | I am looking into buying a Hi-Tech, Super-Dooper, |Ultra-Cool-Neeto, Programmable/Graphing calculator... Right now it is the HP28s. See comp.sys.handhelds for some sample programs. This calculator can do more than you can ask of it. Sean -- *** Sean Casey sean@ms.uky.edu, sean@ukma.bitnet, ukma!sean