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New calculator - no tsure where to put this 3

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SperlingPE

Structural
Dec 27, 2002
591
I am in the market for a new calculator.
It has been several years since I purchased my current calculator and it is starting to decline.
So I have been doing some looking around when I have time and I ran across Texas Intruments Nspire series calculators.

Has anyone used these?
Are they more for the student than for real world use?
I have the basics from TI's web site but I have more questions.

Can you really do yor calculations on your calculator and save them and then down load to your computer?
Fully programmable?
There are some functions that if they work like I think they do would be nice.
 
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I am with you Teguci... using still the HP 48GX. Not an easy transition though if you go to a TI for SE tests.
 
CASIO FX 115ES. Works for me. Not too fancy, but has enough to get the job done. Oh, and works for the NCEES tests too :)

 
HP for me too. had the 48G for a long time - now use the 35s.
 
I still have the same HP-15C that I got senior year in college, which was how long ago??? (many blue moons, fer sure)

An interesting choice is the TI nSpire CX, which is backlit color and way cool. However, the CX does not have the TI-84 keypad option, if that's something you're looking for. I've yet to actually do transfers with a PC, but that's what the software is for. The PC emulator software can also do what the calculator does, and then files can be transferred with the handheld. Bear in mind that it's quite big, although the CX is somewhat slimmer than the previous models. The TI website has a fairly huge collection of user-submitted files, which are mainly school related, but there may be a few goodies there.

One strong feature is the ability to document the calculations, since it does come with alphanumerics. Its graphics are pretty good for graphing, but some of the controls are clunky, but that might be inherent to a handheld machine without a touchscreen. The CX uses a touchpad, like on a laptop, in addition to click pad upon which the touchpad resides. Makes for a slightly faster interface than with just the clickpad.

There are two versions of each generation, to wit, the CX is the basic calculator version, while the CX CAS is the computer algebra system version. The CAS has a bunch of symbolic solvers, i.e., factor (ax^2+bx+c), etc.

Either version has an interface to a TI module for digitizing measurements, primarily intended for students doing chemistry and physics labs, but clearly, it's a possible LabView alternative, although it's not clear the TI has seen that possibility.

In general, the nSpire is radically different than pretty much any calculator around. TI has invested a lot of money to push this into the educational market, but at $150 MSRP, it's a bit steep, although you can wangle one on EBay for around $110 net.

One major change in the CX is that it uses a custom rechargeable NiMH battery; obvious, there are pros and cons with that choice.

I see it as having great potential, but it's always unclear whether the original visionaries and advocates at TI see the same vision that someone from the outside might.

I also have that Casio as well as the TI-30SX which would certainly also do well for most engineering calculations. Either is substantially cheaper than the CX; I think the Casio was under $15 during back to school sales. Nonetheless, the color display, yeah...

One thing that's annoying about all these calculators is that the "exact" mode, wherein answers are expressed as fractions or multiples of pi, etc., and decimal mode is that it's not easy to switch between the two modes.

TTFN

FAQ731-376
Chinese prisoner wins Nobel Peace Prize
 
Another HP-er. Started with 45 and have had a variety since. Settled about 15 years ago on HP 32SII. When they started to go away, I bought a couple of extra ones so I would have them for a long time.
 
HP all the way. My brother-in-law used to be the head of R&D at HP, so I am also hooked on RPL.

I still have my 41CX too, but the printer and card reader are shot. Frankly, I don't know what I'd do without it.

Mike McCann
MMC Engineering

 
A diehard HP RPN advocate here. I've been using RPN calculators since 1990. I'd recommend either the HP35s or 50g for a student depending on whether or not he or she wants serious programming capabilities. For an actual engineer, I'd recommend the 35s because (I think) no engineer programs nowadays and the 35s is much handier. It'll go in your pocket, has very long battery life, keys are very well laid-out, keys have perfect (to me anyway) travel distance and stiffness, etc.

The problem with _some_ 35s calculators is missed keystrokes. The key will click, but nothing will be on the display. I'd say mine misses a keystroke on every 3rd or 4th calculation I try, which is not good. I've learned to watch the display to make sure everything goes in. Mine didn't start doing this until I had it for probably about a month. The solution is to keep your receipt and just send it back for another if you get unlucky and your calculator does this.

From what little I've read about the new TI nspire, it seems to be student oriented. All of my students have TIs and I'm definitely not impressed with their calculator punching abilities. I've pushed the buttons on them a few times and it's no wonder. They're like mush. The calculators feel like toys.

I have a funny story. I was teaching steel a couple of years ago and had the students crank through the AISC Lr equation on an exam. Out of 38 students (all with TI calculators), only four or five were able to produce the number. I'd say 20 of them had the right equation written down, but couldn't get it through the calculator. I knew they might give me grief over it, so I timed myself with my HP48. In three tries, I averaged 23-24 sec. and made zero mistakes. There really is a difference between doing this sort of thing RPN or algebraic.
 
I certainly wouldn't argue against RPN. The only reason I don't use my HP as much as I might is because I usually fire up Mathcad on the PC, and Mathcad does units, which eliminates ALL the unit conversions I'd otherwise have to do with just a calculator.

Algebraic calculators require a certain amount of forethought before attempting a calculation that might otherwise use parentheses. Nonetheless, the new calculators, including the Casio and the TIs do have the ability to mitigate some of that with the "last answer," functionality, i.e., if you hit enter followed immediately by an operation key, the operation will use the last calculated answer as the operand.

TTFN

FAQ731-376
Chinese prisoner wins Nobel Peace Prize
 
I like TI's. Why do they call it Reverse Polish Notation?? Sounds like an oxymoron to me?? Kind of like Army Intelligence??
 
"Reverse" because the operator follows both operands, like A B +, so it's a post-fix notation "Polish" notation has the operator preceeding the operands, like + A B, i.e. a pre-fix notation. Standard arithmetic notation A + B is in-fix.

With the use of an operand stack, parentheses are never required, and there's actually no keys for entering parentheses. For most problems posed with parentheses, you can start immediately on the calculation without even thinking about the parentheses, or whether you've nested enough of them, etc.

TTFN

FAQ731-376
Chinese prisoner wins Nobel Peace Prize
 
Once you get the logic Mike, RPN just comes naturally. Been using it since 1978.

Mike McCann
MMC Engineering

 
I use a HP 48GX and a TI-89 Titanium... one for home and one I carry with me... They are both very good and both good for programming. It's largely a matter of personal preference. My personal thoughts are that HP is slipping a bit with their quality (based on a couple of laptop and printer purchases)

There is little advantage using the RPN notation, except that some calculations can be entered more quickly using RPN... for really complex stuff, I prefere the algebraic logic of TI.

It used to be with the earlier, slower calculators, that the stack architecture used by HP was faster... it mimiced the manner in which data was used by the processor. Now it doesn't matter very much... my TI-89 has a Motorola 68000 processor, once a terror in the times of the Intel 80286.

Dik
 
Could have added that the programming language 'Forth' used a similar stack architecture approach for 'real time' astronomical observatory programming when speed was a real issue...

Dik
 
I'm intrigued by the thought of a calculator that can submit programming and output to a PC, that would be extremely useful. Heck, if I could have mathcad (or similar) on a calculator I don't think I'd ever write out a calculation again! If you do purchase one please let us know how it works.

I'd also love to replace my Casio fx-7400G PLUS (the ti-83's cheaper cousin).

EIT with BS in Civil/Structural engineering.
 
My old HP-42?? was probably the best HP calculator ever made... lasted for a decade only to find out that HP stopped making them.

Dik
 
About 15 years ago I saw all the "youngsters" had 48gx calculators. I figured out that if they were cutting edge for new graduates, I needed to get on board. I bought one and love it. I only use it now for unit conversions and solving quadratic or higher order equations. Every time I push a key, it's one step closer to stopping working. I now use a 35s for my everyday calculating with a 32II for a home backup.
Here's a link for what HP makes now; The 50g looks intriguing, and I think I'll get one to add to my collection. Unfortunately, calculators are going the way of fax machines. I still despise Carly Fiorina for dismantling the calculator division of HP. But no one has convinced me to set up all my day to day calculations on MathCad or Excel.
 
"Carly Fiorina"

I KNEW there was another to not vote for her in the last election ;-)

"if I could have mathcad (or similar) on a calculator I don't think I'd ever write out a calculation again!"

SMath Studio: runs on PCs, and anything that runs Windows Mobile. Unfortunately, there doesn't seem to be a Java version.

TTFN

FAQ731-376
Chinese prisoner wins Nobel Peace Prize
 
I had a Casio FX4000P which I bought sometime in the mid-eighties. Sometime in the late nineties, someone broke into my car and stole my spare pair of glasses and my briefcase containing the FX4000P. The glasses were old, beat up perscription glasses of no discernable use to anyone. The FX4000P, beat up as it was, was worth maybe $0.75 Canadian. The briefcase was new, and I had paid around $180 for it. It was the only thing of value.

The FX4000P was a fantastic calculator. It had an eighty character entry window. I could assign variables. I could string operations together and recover my entry line. Back before I had access to a spreadsheet, it was indispensable. The Casio fx-991MS I have now, is not as good.

On the other hand, I have not really tried to learn it. Spreadsheets are so convenient, and you have a record of your analysis after you are done.

If I ever see an FX4000P in an old junk shop, I will buy it.

Critter.gif
JHG
 
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