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Recommendations for RPN Calculators?
sg3000 asks: "My trusty old HP 48S graphing calculator, that served me since engineering school, seems to be giving up the ghost. I haven't used it in a few years, but recently I put new batteries in it. It works, but it makes a loud static/white noise sound when it's on. The noise is not as noticeable when I hold it, but when I set it down on a hard surface, it's really loud. Then it sucks the batteries down incredibly fast (I put new batteries in it, and two days later, they were drained). Any suggestions on what I should buy as a replacement?"
"I'm in graduate school now, and since I'm taking an accounting course, where they don't want us digging out our laptops during a test, I need to buy another calculator. I'm a big fan of reverse polish notation (RPN), so I'd prefer to get another HP calculator.
Do companies still make calculators? I'd love to get another HP 48, but I'm not even sure if HP even makes calculators like that any longer -- on their web site, they're all cheapo-looking single line deals. I've read about something called an HP 48g, but HP has nothing about it on their web site."
Why does HP's current calculator lineup suck?
It depends on how much money you have, really. I've had great results with my TI-89- it's a calculus student's best friend. The only problem is, it costs about US $120 (at least mine did about 8 months ago). Visit http://education.ti.com/us/product/graphing.html for TI calculators. Better yet, go to http://www.graphingcalculators.net/ before it gets /.ed.
"73% of quotes on the Internet are made up" -Ben Franklin
Depending on how hard you work your calculator, you might do better to get a PDA and run a calculator program on it. If you bang on your calculator keys for hours, get a real calculator.
I use Palm PDAs (my current one is a Tungsten T) and I run a program called RPN on it. It's programmable and it has graphing, but I haven't used those features; but as a general-purpose RPN calculator, it's kept me happy.
What I really want is something similar to Palm RPN that is programmable in Python.
Anyway, the best thing about this is that I always have it with me. I used to have an HP calculator, but it was never handy when I wanted it.
steveha
lf(1): it's like ls(1) but sorts filenames by extension, tersely
The same team that made the 48 worked on the 49.
The only 'problem' with the 49 is the soft non-clicky keys.
Although, it has the added benefit of not being piss slow and has a (thank God) hard case.
I own an 11C that I've had since about 1985, and it's still working fine on the original batteries! I guess I don't use it as much as I should...
Antiquated? You have to be kidding me. I always enjoyed doing group work with people and getting complicated answers in usually no more than half the time of everyone else. RPN is incredibly quicker and easier to use once you step over the learning curve. Anything else is slow and generally error prone.
"Nature doesn't care how smart you are. You can still be wrong." - Richard Feynman
I agree that keypresses saved are minimal, if not sometimes nonexistant in simple equations. In fact, for many simple single-operation equations, the process of learning RPN is far too complicated to justify using it at all.
RPN, however, can be likened to the Dvorak keyboard layout. It is entails a slightly involving process to learn. For many purposes, this is simply a pain. The true power only shines in complicated equations, such as those which make use of brackets.
The following equation shall be typed on an algebraic calculator, followed by an RPN calculator. [;] will be the button name for [Enter].
25 ( 46 ) + 254 - 2462 / ( 645 - 2453 )
Algebraic:
25*46+254-2462/(645-2453);
RPN:
25;46*254+2462;645;2453-/-
In the above example, you will realise that the number of keypresses is exactly the same. (In fact, if you cheat and leave out the second bracket on the algebraic calculator, that calculator edges out the RPN by one keystroke!) However, there are three immediate benefits to the RPN calculator:
Over time, the amount of keypresses will not really be changed too drastically. However, the true power is the convenience and the ease of use. Unfortunately, like the Dvorak keyboard, RPN will slowly fade in the non-specialised markets due to the fact that it takes too much time to learn.
I absolutely, positively HAVE to second this statement. I would not have passed Numerical Methods absent the matrix manipulation capabilities of the TI-92 PLUS to check my grind-it-out pencil-and-paper homework!
Sidebar comment: try doing a Newton-Raphson solution of a system of non-linear equations by hand some time. IIRC, that sucker took about eight hours and nine pages of densely-packed hand calculation (the prof was a "show all your steps sadist" Inverting the Jacobian of PDE's at each iteration and being able to check the interim results in a few seconds was a life saver).
Agreed, completely.
No kidding. I also took a Finite Math course that, while mathematically simple, required an INSANE amount of hand calculation (combinations, permutations, probabilities given a discrete dataset, optimization by solving multiple inequalities, etc., etc., hell, even variations on the theme of compound interest, in a LOT of cases I got through it by coding up custom functions in the TI-92 PLUS's strangish "macro language").
In short, don't knock the entire TI line just because the low end is kind of wimpy. My first, second and third HP programable calculators all cost $450.00 (the first was an HP-45 kiddies). My TI-92 PLUS cost $200 and it can blow the socks off any one of the three HP's.
Don't get me wrong
utter rubbish
No, it's not a rumour(comp.sys.hp48 is your friend).
:)
Pros:
ARM processor -> better speed
Larger screen
SD slot
USB connection to computer
Seems to be emulating the Saturn, since everything else seems to be pretty much the same.
Cons:
Keyboard not registering EVERY keypress (you have to concentrate on pressing a bit harder than usual, it seems)
Much higher power consumption
Bad SD support - you have to remove and reinsert the card everytime you reboot.
USB connection -> no nice HP48modem, etc, hack
Defaults in algebraic mode, manuals only for algebraic mode.
Still haven't found the way to program the ARM directly.
Many of the cons seem to be solvable with ROM updates, so wait and pray for HP to fix them
Try Corewar @ www.koth.org - rec.games.corewar
Try a Palm Tungsten + Power48, an HP48 emulator for PalmOS 5.
Since you already have a dying HP48, you can probably claim fair use of the HP48 ROM image, although IANAL.
Spend your money on a PalmOS PDA and then get Power 48 which emulates the Saturn CPU and runs the HP calc ROMs, it's free and GPL'ed. Though if you can do with something simplier I've been using RPN as others have said, for years (though it's now $18).
Casio's previous graphing calculators have been somewhat lacking, although I applaud their venture to make a 3-color model! The memory and speed limitations, as well as poor quality display, make the old Casios unusable.
Casio has recently come out with something quite different though...the ClassPad 300. This looks like somewhat of a cross between a PDA and a graphing calc. About half the unit is the very large and high resolution (for a calc) display. Many of the keys were removed and virtualized on the touch-screen, and the unit has a stylus built in like any good PDA. The curious part about this calc is that it does NOT have a built in clock, and therefore can't be used as an organizer!
The TI-89, TI-92+, and TI Voyage 200 all have clock buit in, and TI has recently come out with an organizer/calendar/tasklist/addressbook application to load on it. This is what really got me...all the speed and power of a TI calc, tons of applications, and the one I got...the Voyage 200...has a QWERTY keyboard and enough memory (2.7MB) to hold lots of games/programs. The TI-89, while having the added benefit of compactness (and being allowed on standardized tests) has an ABCDE keyboard going across the rows and is more difficult to enter text on, has less than .8MB of RAM, and about half the pixels of the Voyage 200.
Still, if you need a calc for use on the SATs/ACTs I'd recommend the TI-89, otherwise the TI Voyage 200.
Keep your eye on Casio's ClassPad series, though...I think the next iteration of this calculator could really take off if they listened to some user feedback about key layout and PDA functionality!!
While we're having out the HP vs. TI flame war, let me add my kindling...
I have been a user of the TI-series of graphing calculators since they first came out with the TI-85/TI-82 line when I was in high school. My Physics teacher even did work for TI over the summers testing out their "new-fangled" (back then) IR sensors, radar sensors, and the 'CBL' which was basically a hand-held data collection microcontroller that could feed data directly into the TI calc's. Since then, (and since doing regular physics expirements with those instruments BECAUSE he had TI's backing for testing the instruments) I have always preferred TI. But that's not to say I wouldn't change given a better tool.
I currently have a TI-89, and use it for exactly what you described: checking my "equation set-up" before actually calculating. Seriously, who wants to enter thirteen different phasors in some big long equation and hit simply to find out that they flipped a '+' to '-' accidentally? I'm in school for engineering right now, and working full-time as a business analyst doing statistical analysis all day. Do you think I have time to do all the many calculations I do by hand all the time? NO! I also don't care much to worry about how the answer is found, just that it's right, and with the new TI's and their ability to display the entire equation after you've entered it in what I call "human readable format", I can be assured that I entered the equation correctly.
So for those of you '31337' pencil pushers out there, just realize that some of us are trying to get some REAL WORK done during the day and don't have the time to do it the old-fashioned way. I learned the basics, why waste time using the "old way" to do the math when I've got a better tool for it now?
Also, claiming the HP-48 or whatever is superior because it was the "best" back in it's heyday, is like claiming that "640k is enough RAM for ANYBODY!" Get with the times and use the best tool out there. Quit arguing about the brand name.