Calculator bit the dust..... 17

[knelli]

Hi all,
I am on my third TI-85 and the display is failing . I looked at other TI models including the TI-83, TI-84 Plus C SE and TI-89 Titanium. I was able to emulate those models on my phone to see if I'd like them. I still prefer the TI-85, and really want something that does conversions easily. I found the conversion programs on the above models to be cumbersome.

What I would like a calculator to do:
I like a large display and history (like TI-85)
trig and scientific functions
x^2 button square root
^ button so I can do whatever root I need (like x^(1/4))
Conversions, including ft^2 to acre and gal to ft^3 (love the conv menu on the TI-85)
solve quadratic/simultaneous equations easily

It would be nice to have something to do decimal to fraction or add feet and inches and give answer in fraction form.

Should I get an old TI-86? Do they have better longevity than the TI-85?

I do like the RealCalc app for android. Anyone know if it is based on a calculator model?

Anyone have the TI36x Pro? CANON F-792SGA? Looks like the TI36x pro conversions are very limited.

I know a lot of you like the HP with RPN, but I'm not looking to go that route.

 

[Ron]

JC...thanks for the link...I had forgotten that existed. Cool.

 

[tony1851]

Try this; it never wears out, doesn't need batteries and you can drop it/tread on it and it will still work.

 

[XR250]

I am convinced that using RPN is better for your brain on a daily basis. With no parentheses keys, you have to think more about the order of operations and the stack. I'd love to get my kids to use RPN, but I prefer they don't even use a calculator until college.

 

[CELinOttawa]

Another vote for the Casio fx-991ms.

 

[IRstuff]

"Try this; it never wears out, doesn't need batteries and you can drop it/tread on it and it will still work."

Yeah, just don't drop your cigarette on it...

Started with
TI SR51
HP27C
HP41C
HP11C
HP11C -- thought I lost it, like Jayrod, but found it, so there's 2 now

The TI nSPIRE is a somewhat obscure, but powerful calculator. It has a modular keypad that allows for emulation of the TI89.

TTFN
faq731-376

Need help writing a question or understanding a reply? forum1529

 

[GeoPaveTraffic]

I've been using a HP 15C since 1983. My then girlfriend, now wife, bought hers in 1985. Both still in use every day.

Mike Lambert

 

[TomDOT]

Well, have you taken it apart to spot any obvious issues, like a loose display connector or magic smoke escape point?

 

[hawkaz]

Talking calculators to engineers is like throwing red meat to the sharks.

HP11C- Been using it for 32 years and it's still going strong (although I did have to change the batteries three times)

 

[TehMightyEngineer]

Funny, my girlfriend and I had a debate last night about the merits of solving multiple variable equations through "advanced" mathematics or by iterative analysis. She was all for accurate solutions by solving for the variables but I proposed that setting up a simple spreadsheet or mathcad sheet where you input one variable manually and then compare the calculated variables until they matched your input as a more easy to verify and simpler method which is usually faster as well but sacrifices accuracy and automation.

Anyway, we then discussed calculators and software that did such things for us and I thought of this thread. How many people, when faced with some math problem beyond basic algebra, actually do the math or do you "brute force" the equations like I do? If the former, do you employ any advanced calculators, mathcad (which is great for solving for variables), or something similar which can do the math for you and solve for the multiple variables? Or do you choose to write it all out by hand without letting a computer do the legwork?

Maine EIT, Civil/Structural.

 

[EngineeringEric]

TME, For advanced quick math i often use WolframAlpha.com, from the makes of Mathmatica. But if away from my computer i will sometimes use brute force but it is usually a decision based on accuracy or speed (and complexity of algebra required)

 

[TehMightyEngineer]

Ahhhh, I love WolframAlpha and really should use it more often during work. Great tip.

Maine EIT, Civil/Structural.

 

[Agent666]

RPN all the way sorry... Give it a chance, back in university I used to think the same that it was a bit harder to understand so I didn't bother. Then in one exam I decided to use it as there were a lot of calculations with multiple brackets which are a real pain in algebraic mode. I finished the 3hr exam about 1 hour early much to my surprise, which was directly attributed to the efficiency of using RPN and a few programmed equations.

This was on a HP49g, I currently use a HP50g after that died an unexplained death. I couldn't imagine using anything else now to be honest. It does everything you are after, and doesn't have to be used in RPN mode.

I can't even function on an algebraic calculator anymore as it is to be honest a completely different thought process, I guess it's like my workmates when they pick up my calculator for a quick calculation and they are horribly confused by RPN to the point where they hand it back to me to do the calculation for them!

 

[msquared48]

"...and they are horribly confused by RPN to the point where they hand it back to me to do the calculation for them!"

Love it...

Been using it for so many years, I just cannot use a TI.

TI operation: 4 X 5 =

HP operation: 4 enter 5 X

Still 4 keystrokes to get the answer...

Mike McCann
MMC Engineering

 

[jayrod12]

And that's why I find RPN confusing. when someone asks me what's A times B I think of A x B = ??, not A enter, B times. it's so backward.

 

[jayrod12]

and if you can't figure out the order of operations and basic algebra easily enough to use a standard calculator then you probably have bigger problems in your life you should be figuring out, like what you did to screw up grade 6 math.

 

[XR250]

TI 3 + (4x3)= 8 strokes

HP 3 enter 4 enter 3 X + 7 strokes


Once you get used to it you will never go back

 

[Archie264]

4 enter 3 x 3 +

Six strokes

 

[connect2]

yes always have had an HP calculator. Bought this latest HP35S not sure 6 or 7 years ago. The only thing I don't like about it is, in this day and age, why HP couldn't have gotten a better display. Perhaps it's just my eyes. If someone hands me an ordinary calculator I hand it back and go get mine. Not sure how many times I've punched in 5wl^^4/384EI but it's likely in the 10's of 1000's.

 

[Archie264]

PS: Excel, I was trying to reinforce your point, not counter it. With equations that have parentheses I try to start within the parentheses to save a stroke. Another thing I do is that if the equation contains pi I try to start with pi as that saves a keystroke as well.

Another advantage of RPN over some types of algebraic calculators is that it shows intermediate calculations, which can be handy.

As you said, once you get used to it you'll never go back.

 

[Archie264]

knelli,

I just noticed that one of your criterion is "...solve quadratic/simultaneous equations easily..."

For that you'll need a calculator that can handle matrices. In the old days the HP 15c and 42s would do that, and do it easily. They still will, you'll just have to buy them off of ebay, though. But, I'm sure there are all kinds of wiz-bang calculators that can do it now, I just don't happen to know which ones they are.

Also, you can set up an excel spreadsheet to solve for simultaneous equations if you want. See here:

http://educ.jmu.edu/~drakepp/spreadsheet/howto/matrices.pdf