# Graphing calculator... TI or HP?

Specswise the HP is very nice, it seems to have everything the TI has and a little more. It's pretty hard however because I can't find much comparative data between the two. I've also read that the calculator is very fast compared to previous HP models but I don't know compared to the TI-89.

Anyways am I being stupid should I just get the TI-89 and save myself the pain of having to learn the HP on my own? Or should I go for the seemingly better and cooler 49G+? Should I be looking at calculators as well? Thanks for your advice.

## Comments

142member129memberI may be wrong about the 89, perhaps my friends had some kind of shell on theirs, but I hated it. But hey, there are really nice games for it, and that's what you buy calculators for, right?

135member319memberRPN also has ruined me --- I simply cannot use a "normal" calculator. I have a 20S and a 32S. The look exactly the same to the eye, but the 32S is RPN. I keep the 20S in case a student forgets theirs on exam days (but I can't use it).

Everyone and their brother has a TI, so if compatibility matters to you, get a TI. I found it somewhat ironic however that someone on AI is reccommending a TI pretty much because it is what everyone uses.

I wasn't aware the HP49G+ was out yet. Damn. Another electronic tasty to covet.

390memberOriginally posted by KeilwerthRebornI liked that I could use it exactly like a regular old scientific calculator when I needed to (the 89 seemed to take longer to use, and was confusingWhen I first began using the 89 (from an 82), I felt exactly the same way. But after a few months with the 89, I can't go back to the 82. The 82 and 83 are fairly straightforward interface-wise, but the 89 has a definite learning curve (function key layout, dynamic menus, etc.). Still, spend a little time with it and there's no turning back. I'm afraid I can't offer any advice about the HP models because I have no hands-on experience with them, but I can wholeheartedly recommend the TI-89.

151memberOriginally posted by hyperb0leI'd go with the TI-89, mainly because every once in a while, a teacher will write a program for the TI-89, and expect the students to be able to use it. Functionally, both calculators are probably pretty similar, but all the people I know who have used non-TI calculators in math classes have had pretty serious trouble using it, and eventually just borrowed a TI from the teacher.This is definitely a concern but I suppose it'll be an incentive to truly learn the calculator.

Originally posted by KeilwerthRebornWell, I know that the TI-89 is an absolute bitch to use, at least for me. I used a TI-83+ all through high school and my one math class in college (done with math now, yay!), always liked it, and never found it lacking in functions. I liked that I could use it exactly like a regular old scientific calculator when I needed to (the 89 seemed to take longer to use, and was confusing), and the BASIC on it was easy enough for me to write menu-based programs for calculations quickly, without ever reading a manual (plenty of trial and error, but that's fun).

I may be wrong about the 89, perhaps my friends had some kind of shell on theirs, but I hated it. But hey, there are really nice games for it, and that's what you buy calculators for, right?

Isn't the TI-86 similar to the TI-89 GUI-wise just not as good? I admit you can't pick everything up right away but I'll have to take time to learn whatever I get either way. I am confused what you mean by having a shell on their calculators? As for games, that isn't a deciding factor but it'd be nice to have

I would like to do some programming on it for fun, does the 89 not use BASIC? What do HPs use? Any advantages in this area? Again, not a deciding factor but I'd use it.

Originally posted by jginsbuI'd go with the HP. But, to be fair, that's because I can't use non-RPN calculators anymore. Basically I recommend HP because I recommend RPN. In my experience people either love RPN and won't go back to anything else, or they can't stand it and never get started. It might be worth finding out how you react to RPN: that could make your decision for you.I looked up RPN and it seems interesting. It doesn't look like it'd be that hard to pick up, although doesn't always having to hit enter get annoying? Does that not create a newline? On the site I read, it's supposedly much more efficient for the calculator. Is it simply faster to use? Is that the main advantage? Can you just take an equation with parentheses and easily translate it into RPN after practice?

I'm definitely willing to try it but is it all or nothing? Can you simply not use parentheses? Is that what they call "algebraic data entry"? On the specs it states "Entry system logic: RPN, algebraic and textbook". What is "textbook" exactly? If you look on Amazon's stock photo it appears that there are parentheses above the minus sign and brackets above the plus sign. Will I not be able to just simply write "5+5" or will I have to do "5 [enter] 5 [+]" if I get an HP?

Originally posted by machemRPN... LaTeX... Apple Computer. Yup, I definitely see a pattern here.

RPN also has ruined me --- I simply cannot use a "normal" calculator. I have a 20S and a 32S. The look exactly the same to the eye, but the 32S is RPN. I keep the 20S in case a student forgets theirs on exam days (but I can't use it).

Everyone and their brother has a TI, so if compatibility matters to you, get a TI. I found it somewhat ironic however that someone on AI is reccommending a TI pretty much because it is what everyone uses.

I wasn't aware the HP49G+ was out yet. Damn. Another electronic tasty to covet.

Same thing, is the advantage simply the speed at which you can enter in equations?

Compatibility-wise, again I'll have to evaluate that and see if it'll be a problem. I think I use a Mac more because I prefer them to PCs. Not necessarily because I want to go against the crowd. Here, it seems like the calculators are pretty much the same, so there's not really a clear advantage of one over the other. Can anyone that's used both tell me how the interface/menu system is? Is one better than another's?

It seems the the 49G+ is pretty new, just came out a few months ago. The 49G apparently had problems with its buttons but supposedly the problem has been rectified with later batches of the 49G and the 49G+. I am still curious about the "cheap" comment that's been made by a few people. Are there any good generic stores I can go to see one in person? Circuit City, Best Buy, Radio Shack, etc...?

Again thanks for the replies

151memberOriginally posted by cooopWhen I first began using the 89 (from an 82), I felt exactly the same way. But after a few months with the 89, I can't go back to the 82. The 82 and 83 are fairly straightforward interface-wise, but the 89 has a definite learning curve (function key layout, dynamic menus, etc.). Still, spend a little time with it and there's no turning back. I'm afraid I can't offer any advice about the HP models because I have no hands-on experience with them, but I can wholeheartedly recommend the TI-89.Thanks, if I do decide to go with TI, I'm definitely going for the 89.

I also forgot to ask... the HP comes with a USB cable and PC only software (I'm sure the PC is the same in this respect). I've found a site which has some cool apps and a few games for the HP and I was wondering if there was any possibly OS X or Unix app that could interface with either calculator? I have VPC which would be a pain but would that work otherwise?

Also I was reading some other reviews for another calculator and noticed this feedback:

"As for HP, well they've re-entered the calculator business; the HP 49G+ will be available by the end of September, based on a processor more than 4 times faster than the original HP 49G. Add to that a standard USB interface (Just like the one you use to plug in your digital camera) and a built-in SD card slot, it'll be hard to beat for memory upgradability. And I hear they'll be re-introducing the equation library. For those of you who don't know, the equation library brought together a bunch of formulas from economics, physics, engineering, etc. and made them available through a menu system -- instant crib notes! Can't wait to see a final production model. "

It's dated but does anyone know anything about this. I could of sworn I saw a mention of "equations from previous model" coming back to the 49G+. Is this possibly related to the HP's feature of "over 2,300 built-in functions"?

OK, that's it for now and I'm going to get some sleep

135memberOriginally posted by SynoticI looked up RPN and it seems interesting. It doesn't look like it'd be that hard to pick up, although doesn't always having to hit enter get annoying? Does that not create a newline? On the site I read, it's supposedly much more efficient for the calculator. Is it simply faster to use? Is that the main advantage? Can you just take an equation with parentheses and easily translate it into RPN after practice?

It isn't hard to pick up at all. The problem for most people who do pick it up is that they forget how use a calculator any other way.

RPN really isn't used for entering equations, at least not on the HP calculators I own (32S, 48SX, 48GX). It is used for doing calculations, and for that purpose it results in a savings of keystrokes over normal entry because there are no parentheses. It is also faster because operators _always_ follow data (that's the "Reverse" of "Reverse Polish Notation").

As for hitting enter: no, it's not annoying, and you don't have to hit [enter] after every number. Remember that RPN is _stack_ based; [enter] inserts a number into the stack without performing any operation on it, while all other operators perform an operation on one or more registers of the stack and enter the result back into the stack. [Enter] tells the calculator: "I'm done inputting this number; put it in the bottom register of the stack." It doesn't have anything to do with a new line in the usual sense.

Here are a couple of examples:

To calculate 4*(2+3) in RPN:

2 [enter] 3 [+] 4[*]

That's six keystrokes in RPN compared with eight the normal way. You could also have done (but this is longer):

4 [enter] 2 [enter] 3 [+][*]

In either case, these are just the sequences of keystrokes; you never see a line on the calculator's screen with that on it.

Want to perform another operation on that result? Take the square root for example? Just hit the square root key -- one keystroke. IIRC, that takes three keystrokes on a TI. Results of previous calculations are just numbers in the stack like any other, and operators can be applied directly to them (this is, in fact, how all multi-operator calculations are performed: every operation is discrete).

In RPN you're responsible for order of operations, but you gain a lot in efficiency. The critical thing is to grasp how the stack works.

Originally posted by SynoticI'm definitely willing to try it but is it all or nothing? Can you simply not use parentheses? Is that what they call "algebraic data entry"? On the specs it states "Entry system logic: RPN, algebraic and textbook". What is "textbook" exactly? If you look on Amazon's stock photo it appears that there are parentheses above the minus sign and brackets above the plus sign. Will I not be able to just simply write "5+5" or will I have to do "5 [enter] 5 [+]" if I get an HP?

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On the HP calculators I have, RPN is the default. You can enter calculations algebraically by putting them between single quotes. This is also how you enter equations and expressions. Textbook allows you to enter equations in fully formatted textbook layout: the calculator will insert parentheses and convert it into single line algebraic format for you. I don't know if the 49G+ is more "modal" than the old models, i.e. you can put it into algebraic mode and it will function just like a normal calculator.

7,311memberThis alone is reason to buy it.

1,103memberOriginally posted by SplinemodelThe HP operates in postfix.

This alone is reason to buy it.

What's that mean?

199memberOriginally posted by AmoryaWhat's that mean?It's another way of saying RPN...

Prefix notation: +ab

Infix notation: a+b

Postfix notation: ab+

5,012memberHP, well I've never used but I guess some people seem to love it. I've always wondered why people would use prefix and postfix notation. It used to seem pointless in my computer programming class.

199memberOriginally posted by ast3r3x89 is reason to use it because everyone else does.

HP, well I've never used but I guess some people seem to love it. I've always wondered why people would use prefix and postfix notation. It used to seem pointless in my computer programming class.

Well, for one thing, there are no order of preference ambiguities (i.e. no need for parenthesis). Also, therefore easier to parse programatically and what-not. If you can think in a stack based mindset it (well, postfix at least) seems perfectly natural.

135memberOriginally posted by ast3r3xI've always wondered why people would use prefix and postfix notation. It used to seem pointless in my computer programming class.There are some advantages to PN and RPN

as notations, but they are usually outweighed by their disadvantagesas notations. PN fell out of favor in symbolic logic for good reasons.But

notationis an entirely different matter than aninterface. Here the advantages are quite significant and the disadvantages few, especially on the HP models (like the 49G+) that allow you to enter expressions in standard algebraic notation when you wish.151memberJust some things I've gathered: The 49G has problems with crashing, the keys are really loud, it can have problem with things like adding 5+6 and getting 10.999999, it also has no printed manual at all. It seems that the 49G is a more powerful calculator and more expandable but just badly designed. Also the TI-89 supposedly has a higher pixel density. These are just some of the things I've read about it.

Anyways just because although the HP calculator seems a lot more powerful (they also use a better algebra system I've heard) the model itself just has too many problems to persuade me to choose the time-tested TI-89. So that's what I'm planning on now. Unless anyone can persuade me otherwise in the next few days. It's kind of unfortunate, if I got the 49 I was planning on doing comparisons with photos and whatnot

2member5,012memberOriginally posted by SynoticThanks for all of your responses... I did a bit more research a while ago and I think that I'm probably going to pick up the TI-89 in a few days. I made an effort to at least look around but for my needs it seems like it would be better.

Just some things I've gathered: The 49G has problems with crashing, the keys are really loud, it can have problem with things like adding 5+6 and getting 10.999999, it also has no printed manual at all. It seems that the 49G is a more powerful calculator and more expandable but just badly designed. Also the TI-89 supposedly has a higher pixel density. These are just some of the things I've read about it.

Anyways just because although the HP calculator seems a lot more powerful (they also use a better algebra system I've heard) the model itself just has too many problems to persuade me to choose the time-tested TI-89. So that's what I'm planning on now. Unless anyone can persuade me otherwise in the next few days. It's kind of unfortunate, if I got the 49 I was planning on doing comparisons with photos and whatnot

Well technically 10.99999 repeating is the same as 11, so at least it isn't wrong

860memberThe 89 definitely spoiled me during high school and is definitely needed in my engineering education. It is annoying that it probably takes $1 to manufacture an 89 though (quite old tech in there). Sometimes the 89 can feel slow during complex plots (10mhz 68020 compared to the 49G+'s newer 75mhz ARM), but it's responsive mostly.

151member7,311memberOriginally posted by ast3r3x89 is reason to use it because everyone else does.

HP, well I've never used but I guess some people seem to love it. I've always wondered why people would use prefix and postfix notation. It used to seem pointless in my computer programming class.

The TI 89 is awful. The input line is so small, and the screen is so cluttered. It is WAY TOO EASY to make parenthetical errors. Postfix eliminates the need to use parens, and thus vastly decreases the amount of time I need to spend on a TI checking to make sure I put everything in correctly.