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Calculator Input
12

Calculator Input

Calculator Input

(OP)
My old canon calculator I've had for 21 years finally gave up the ghost.

Ive been trying my son's canon calculator but dont like the input method, e.g. sin, cos, square root before number input i.e. operation done as you would write it on paper. They all seem to be like this nowadays.
I think the older calculators used reverse algebraic input, but they dont seem to have them anymore. I know Hp have RPN but dont want to get HP anymore prefer casio or canon.

Anyone have any suggestions ?

RE: Calculator Input

Real engineers use RPN - Nuff Said!

RE: Calculator Input

Just get one and get used to it.

RE: Calculator Input

My TI calculator has the input type you like. TI-30XA, but it is old and probably superseded. I used to like Canon as well, but they don't seem to be making my type anymore. The RPN guys like to pay a lot. Not worth the learning curve, IMHO, and I used one for a long time.

RE: Calculator Input

Newer HP RPN's can work in algebraic mode while you learn. The keys on their flagship models (50g) have lost the tactic feel which sucks. 32S is still a nice, low cost, tactile keyed machine. I have a $10 HP15C app on my phone that comes straight from HP. Frankly, I use it for 90% of my calcing theses days. Programming is better done in desktop apps nowadays.

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.

RE: Calculator Input

HP for 40 years! Have only had 1 calculator die on me in that time....a 32SII that was about 15 years old.

RE: Calculator Input

(OP)
Im old fashioned, dont like iphone apps, prefer to use real calculator.
Used Hp45 for about 10 years so I know about RPN. I think Hp is good not great very overated. My canon I now realise was very underrated. May give canon F-792SGA a go very cheap from amazon and ships to Australia.

Anyone have this calculator ?

RE: Calculator Input

32SII def. did not hold up like the 11C or 15C. Had at least 3 die on me. I am using an 11C right now that I bought off ebay and a 15c app on my iphone.
Been teaching my 14 yo daughter to use RPN for her chemistry class. I think she is hooked.
Can't really see going from RPN back to algabraic. The RPN is more efficient and gives your brain more of a workout.

RE: Calculator Input

I think the TI-89's allow the user to use rpn. They're very good calculators.

RE: Calculator Input

My biggest problem with RPN calculators

when HP upgraded their flagship G-series RPN calculator, they put the divide where the drop was, X where the divide was, - where the x was, + where the - was, and enter where the + was....

i've hated them ever since.

RE: Calculator Input

I have a casio fx-991MS. It's exactly like you want. Number first, then operator (classic scientific calculator). I refuse to go to RPN. The only calcs I'm doing with a calculator are simple nowadays anyway. Anything remotely involved I'm using excel.

RE: Calculator Input

3
RPN like I did never

RE: Calculator Input

@PMR

haha that was actually clever.

RE: Calculator Input

2
It’s demonstrable that RPN saves keystrokes. RPN also shows intermediate results and there’s no need to use parenthesis or a memory storage button. That doesn’t make RPN better, necessarily, but just be aware that it’s not simply a stylistic issue; it’s more efficient, as measured by keystrokes. As for algebraic calculators wherein the user types in the whole equation before getting any result I see no advantage to that over simply using Excel to do the same.

I believe there are three calculators that are accepted by the NEECS testing folks: a Casio, a TI, and an HP. If one of those tests is in your future I’d select from the models on their list.

RE: Calculator Input

Quote (Archie264)

it’s more efficient, as measured by keystrokes
Exactly. Even for day to day stuff it will save time = money.
Same reason I use a Mac over a PC but let's not go there….

RE: Calculator Input

So I save a few keystrokes, if I don't make any mistakes. Which would likely take forever for me to stop doing, so in the end I consider it a wash. Maybe when my hand is forced by my casio (and the backup casio still in the wrapper) dying and there being no other option but RPN, I'll get one and learn it.

Until that time, no thanks.

RE: Calculator Input

I've discovered a hidden drawback of RPN.

After a couple of decades of RPN'ing, I had to take an important exam using a non-RPN calculator. As I studied and worked problems with the calculator, I found that I was coming up with incorrect answers much of the time. Worse, it was a systemic problem. I'd run the same calc five times and get the same, wrong answer all five times. Eventually, I realized that I'd forgotten how to do order of operations. Or, more precisely put, I'd forgotten how to care about doing order of operations. That stuff's irrelevant in RPN which is, of course, normally a selling point. It took me a few days to start getting correct answers again and, even at that, I didn't feel anywhere near as confident on the exam as I would have were I using my HP.

It is for this reason that I've specifically not imposed RPN on my offspring despite an almost overwhelming urge to tie RPN usage to allowances.

Quote (PMR06)

RPN like I did never

Love it!

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.

RE: Calculator Input

What exam force you to use an non-RPN calculator.

RE: Calculator Input

@KootK;
That is one of the things I love about RPN is that it makes you do some mental mathematics. Keeps the old noggin youngish.

RE: Calculator Input

Quote (Archie264)

What exam force you to use an non-RPN calculator.

One of the older versions of Washington state's SE exam. In the end, it turned out that they would have been okay with a non-communicating HP. Back in the day, however, the state exams were a bit less organized than they are now and the instructions sometimes left a bit to be desired. Plus they'd only communicate with me via registered international mail.

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.

RE: Calculator Input

@Kootk - Sorry, I misread your post about order of operations. Now I get it.

RE: Calculator Input

Quote:

One of the older versions of Washington state's SE exam. In the end, it turned out that they would have been okay with a non-communicating HP. Back in the day, however, the state exams were a bit less organized than they are now and the instructions sometimes left a bit to be desired. Plus they'd only communicate with me via registered international mail.

Ah, ok, thanks.

RE: Calculator Input

Quote:

As for algebraic calculators wherein the user types in the whole equation before getting any result I see no advantage to that over simply using Excel to do the same.

If you are sitting at a desk with a computer on it, I see no advantage in using a calculator for anything. I have one sitting o a bookshelf over there, but I can't remember the last time I used it.

Doug Jenkins
Interactive Design Services
http://newtonexcelbach.wordpress.com/

RE: Calculator Input

(OP)
RPN doesn't stack up !

RNP is good but not perfect IMHO. The stacks are limited (there are about 5) so that for a really long chain calculation the stacks may not be enough to do the entire calculation and results are lost along the way. At least this is what I can remember with my HP45 in my student engineering days.

RE: Calculator Input

RPN only* has 4 stacks, actually. And in many years of using it on a near-daily basis I've never needed a fifth one. The key is to start "inside" the equation and work your way out.

*Algebraic has 2 stacks.

RE: Calculator Input

It's also important to note that the stacks on most of the HP's are infinite. You lose things from view but they're still there for use. Like a calculation Jedi, you just have to learn to trust. Stacked RPN systems are so easy to use that people seem to forget that they also have very good memory key functionality as well, just like the *cough* lesser products.

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.

RE: Calculator Input

My HP48G finally gave up the ghost so I moved to the HP50g. The tactile feel is a little bit strange but not unbearable, you get used to it. What bothers me more is the re-arrangement of all the keys and the missing "drop" and "swap" keys which were very handy. The one other minor problem I noticed is when keying in successive digits quickly, try keying in a 22 quickly and you will see what I mean, the calculator will only take one of the keystrokes. This can be slightly annoying.

It is kind of sad when a perfectly good product is discontinued for an inferior product.

A confused student is a good student.
Nathaniel P. Wilkerson, PE
www.medeek.com

RE: Calculator Input

Quote (HP48G)

My HP48G finally gave up the ghost

I had two and lost both to bunk enter keys. The tactile keys are great but I think a little more delicate than other styles.

Quote (Medeek)

The one other minor problem I noticed is when keying in successive digits quickly, try keying in a 22 quickly and you will see what I mean, the calculator will only take one of the keystrokes. This can be slightly annoying.

I went bongos over this initially too. It can be fixed by messing with the KEYTIME variable.

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.

RE: Calculator Input

"It's also important to note that the stacks on most of the HP's are infinite."

HP calculators have 4 stack registers, often referred to as X, Y, Z, T, which can be verified by pushing stuff onto the stack and then rolling the stack. Enter 1, 2, 3, 4, 5 then R↓, and you get 5, 4, 3, 5, 5, 4, 3, 5, 5 That's because the X register is the display register, so R↓ pushes the 5 in the X register into T, and the 5 that was entered, which wound up in Y, gets rolled into X and is displayed.

some HP emulators actually allow you to see the 4 registers.

As for the number of registers, since common math operations are binary operations with two operands, there would not be any need to have much more than 4 registers. If there were more than 4, humans would tend to lose track of what's in which register beyond 7. HP made the T register self-replicating, in the sense that if you pop things off the stack, T remains the same, i.e., enter 1, 2, 3, clear, +, clear, +, clear, +, clear, +, and 1 keeps showing up.

TTFN
I can do absolutely anything. I'm an expert!
homework forum: //www.engineering.com/AskForum/aff/32.aspx
FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers

RE: Calculator Input

Quote (IRStuff)

HP calculators have 4 stack registers

On my 50g:

1) Type 1,2,3,4,5,6,7,8,9
2) Hit [+] eight times.
3) Result = 45

Infinite stack on some models. I found the four stack 32S a bit limiting for the California surveying exam. I actually had to write some intermediate values down which I found thoroughly unacceptable.

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.

RE: Calculator Input

>>>I found the four stack 32S a bit limiting for the California surveying exam. I actually had to write some intermediate values down which I found thoroughly unacceptable.<<<

Those must have been some hellatious equations.

RE: Calculator Input

Quote (Archie)

Those must have been some hellatious equations.

Not really. The ones that I remember were just location tracking. Here's how I would have done it on my real HP:

1) Clear stack.
2) Enter starting elevation and leave on stack.
3) Calculate elevation change over 2% cross slope to side of road. Leave on stack.
4) Calculate elevation change to apex of vertical curve. Leave on stack.
5) Enter depth to bottom of manhole thing. Leave on stack.
6) Burrow underground at 1% for 100' for some reason. Leave on stack.
7) Aim for the zenith less 15 degrees and travel for six chains. Leave on stack.
8) Travel vertically 2.25 rotation on a 6" pitch helical travel path.
....
38) Hit enter until there's only one number left

Yeah, I could have kept a running total somewhere. But why should I have to? I have trust issues and infinite stack technology has been around since the 90's.


I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.

RE: Calculator Input

For those who still love RPN and the old HP41/42 (my late 1970's 41c died several years ago as the recharagable battery pack gave up and I could not find a replacement), Free42 (http://thomasokken.com/free42/) is now my calculator of choice on both my computer and my phone.

RE: Calculator Input

Quote (IDS)

If you are sitting at a desk with a computer on it, I see no advantage in using a calculator for anything. I have one sitting o a bookshelf over there, but I can't remember the last time I used it

Seriously? If you are using a computer for everything, you are wasting time. I can size a beam on my calculator faster than I type in the job name in my fancy beam program.

RE: Calculator Input

Quote (XR250)

Seriously? If you are using a computer for everything, you are wasting time. I can size a beam on my calculator faster than I type in the job name in my fancy beam program.

No, I don't waste any time. There is nothing that can be done on a calculator that can't be done at least as quickly on a spreadsheet. And with a spreadsheet you have a record of what you just did, access to much more sophisticated procedures on the spreadsheet or using VBA, and you can also interact with all sorts of other software.

I'm not saying there is anything wrong with using a calculator, there are lots of calculations where they are just as good as a spreadsheet. Just for me they don't add any value.

Doug Jenkins
Interactive Design Services
http://newtonexcelbach.wordpress.com/

RE: Calculator Input

The calculator still has its place, the slide rule does not.

The reason for taking the time to create a spreadsheet is simple, once you do a problem there is no point in having to re-invent the wheel each time you encounter a similar problem. I have many worksheets for lots of seemingly insignificant problems that I could probably hand calc but as IDS suggest for most jobs you need a record of the calculations and the spreadsheet saves me from writer's cramp.

@KootK

Thanks for the KEYTIME tip on the HP50g, just fixed that.

A confused student is a good student.
Nathaniel P. Wilkerson, PE
www.medeek.com

RE: Calculator Input

Kootk, I would have just summed it as I went. And if it was indeed 38 terms I might have also written them down individually to run a double-check calculation at the end of it all as I don't trust myself to get that many of them right. Now with an adding machine, on the other hand...but I suppose that belongs on the accounting forum...bigsmile

RE: Calculator Input

I learned engineering on a slide rule in 1967 before calculators. My first work calculator was a HP45 and several others over the years. I'm still using a HP41 and got used to RPN since the beginning and have trouble with an algebraic calculator. I keep a slide rule in my desk just incase the big EMP comes and wipes out my HP Z800 WS with 12 cores and my HP41.

_____________________________________
I have been called "A storehouse of worthless information" many times.

RE: Calculator Input

Circular slide rules are best because you don't have to back up when dividing.

RE: Calculator Input

I just got the free m48 app for my iPhone 6 Plus. There is also an m48+ app that costs $10. I am impressed they programmed this app to function and look just like an HP 48GX.

RE: Calculator Input

This is the thing that perplexed me about RPN; people who say it's better write this:
1) Type 1,2,3,4,5,6,7,8,9
2) Hit [+] eight times.
3) Result = 45

but really do this:

1 <enter> 2 <enter> 3 <enter> 4 <enter> 5 <enter> ... 9 + + + + + + + +

vs algebraic

1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 = 45.

RPN requires more key presses and produces intermediate answers that don't match the output for the series addition.

While I appreciate that RPN has some efficiency in some cases, it never appealed to me to be a human optimizing compiler for translating algebraic functions to post-fix notation and to reorder operations to comply with an alternate philosophy.

RE: Calculator Input

You could do the sum on an HP more or less the same as you could on an algebraic, making the calculation equally efficient.

I was forced into using RPN in college. It took me about two weeks of frequent calculating to get acclimatized. My brain was plastic enough back then to pick it up swiftly. There is always something elegant and beautiful about the method that is optimally efficient in my opinion. That's why I like RPN, not because I'm convinced that I get to go home six secondS earlier each night because of RPN efficiency.

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.

RE: Calculator Input

Quote (Kootk)

There is always something elegant and beautiful about the method that is optimally efficient in my opinion. That's why I like RPN, not because I'm convinced that I get to go home six secondS earlier each night because of RPN efficiency.
Totally agree. I probably actually waste more time using RPN as the HP11C I use has a pretty slow processor so you have to be careful not to get ahead of it - especially doing deflection calcs. After you hit 4y^x you have to pause to let it complete or you will get wrong answers. This was really a problem in college as I was punching numbers alot faster. The 15C solves this problem with a faster processor.
I figure any tool you use day in and day out should be elegant and beautiful as long as you are not compromising too much efficiency. Same reason I enjoy my Mac everyday.

RE: Calculator Input

IRStuff - sure. I was making a bit of fun of the example. At best there's no special advantage to RPN, except that HP had nicer keypads. At worst, RPN (and other post-fix notations) require a larger mental model of the operations to keep the operations straight. Also, RPN calculators don't get borrowed as much in an algebraic calculator world.

RE: Calculator Input

Quote (3DDave)

At best there's no special advantage to RPN

I must object here. While I won't argue that RPN use is a significant efficiency improvement, it definitely represents an efficiency improvement. See wikipedia's explanation below which we may or many not choose to accept. The advantage may be nill for straight adding but it grows for more complex calculations, particularly where parentheses are involved. Given the prevalence of post-fix algorithms in computer science, it's a pretty hard to accept that there's no efficiency advantage. When in doubt regarding efficiency matters, see machines.

Quote (3DDave)

Quote (3DDave)

RPN (and other post-fix notations) require a larger mental model of the operations to keep the operations straight.

My experience is the exact opposite. With RPN, I find that I can start most anyplace that I see low hanging fruit and a path to completion will emerge without much effort. And it's almost impossible to make errors with order of operations in RPN because whatever operation you're performing will be executed on incoming arguments that sit right in front of your nose to be verified.

Quote (Wikipedia)

Practical implications
In comparison, testing of reverse Polish notation with algebraic notation, reverse Polish has been found to lead to faster calculations, for two reasons. Because reverse Polish calculators do not need expressions to be parenthesized, fewer operations need to be entered to perform typical calculations. Additionally, users of reverse Polish calculators made fewer mistakes than for other types of calculator.[5][6] Later research clarified that the increased speed from reverse Polish notation may be attributed to the fewer number of keystrokes needed to enter this notation, rather than to a smaller cognitive load on its users.[7] However, anecdotal evidence suggests that reverse Polish notation is more difficult for users to learn than algebraic notation.[6]

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.

RE: Calculator Input

Ha, this good! Maybe we'll get a post count comparable to the climate change threads!

My personal experience, given Excel vs. HP11C is that lots of nested parentheses can get quite confusing, and if there are more than 4 to 5 nestings of parentheses, I have to double check to make sure I closed the parentheses correctly.

In any case, to each their own; just as there are people passionate about ME and people passionate about English Lit. and so forth, I can certainly see that algebraic vs. RPN might come down to just personal preference/personality.

TTFN
I can do absolutely anything. I'm an expert!
homework forum: //www.engineering.com/AskForum/aff/32.aspx
FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers

RE: Calculator Input

In Excel you can separate the parts of a formula using shift-enter which places segments on individual lines, making for much easier reading.

I think RPN is to human-computer interface what Esperanto is to language, a solution to a problem that isn't severe enough to make the transition worth it for most users.

RE: Calculator Input

Crud; in Excel it's left alt-enter. Shift-enter is used in a number of other editors for new-line without a paragraph break.

RE: Calculator Input

Yeah, we're obviously just in different camps. Short of an alien invasion, I think that Esperanto adoption would be the fasted route to global harmony. I'd be on board 100% if there were a critical mass of folks serious about it.

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.

RE: Calculator Input

Excel - doing all your sin and cos in radians? Yeck (why calculators can default and spreadsheets can't?)

RE: Calculator Input

Had no idea what RPN was. Had to look it up. Kind of want my money back from my math degree now...

RE: Calculator Input

Quote (Jerehmy)

Had no idea what RPN was. Had to look it up. Kind of want my money back from my math degree now...

Sadly, RPN appears to be slowly dying - similar to the manual transmission.

RE: Calculator Input

Quote (xr250)

Sadly, RPN appears to be slowly dying - similar to the manual transmission.

As a car enthusiast, my car is and will always be a manual transmission.

I had to Google RPN as well, I am too proficient with my TI-89 or TI-30 to change my ways.

RE: Calculator Input

"Excel - doing all your sin and cos in radians? Yeck (why calculators can default and spreadsheets can't?)"

true, but radian is somewhat more engineering friendly than degree. A radian angle deviation multipled by the radius arm results in the arc length. You have to convert degree to radian to do that. Of course, in Mathcad, it's irrelevant, since it does the conversion on the fly.

TTFN
I can do absolutely anything. I'm an expert!
homework forum: //www.engineering.com/AskForum/aff/32.aspx
FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers

RE: Calculator Input

My brain still thinks in degrees. I can't visualize 1.309 rads but I can visualize 75 degrees. It's a simple conversion to include in excel.

RE: Calculator Input

Quote:

This is the thing that perplexed me about RPN; people who say it's better write this:
1) Type 1,2,3,4,5,6,7,8,9
2) Hit [+] eight times.
3) Result = 45

but really do this:

1 <enter> 2 <enter> 3 <enter> 4 <enter> 5 <enter> ... 9 + + + + + + + +

3DDave,

No regular RPN user does it that way. We do it as described by IRstuff, i.e.:

1<ENTER>2+3+4+5+6+7+8+9+ (45 is displayed)

There are many scenarios where RPN requires the same amount of keystrokes as algebraic but there are no scenarios where it requires more. None that I can think of, at least.

RE: Calculator Input

If you have a 4 stack HP and want to find the powers of 2, you can hit 2 enter enter enter enter (loads up all the stacks) then hit x x x x x x x x x x x x x x forever etc.
Basically half as many keystrokes as an algebraic calc. Of course, how many people do this calc on a regular basis - maybe com. sci majors :>

RE: Calculator Input

Excel has the Degrees() and Radians() functions to make it plainer which is in use; though I think the lazy MS developers should have used cos() and dcos() for clarity and ease. More perplexing is that Excel has no units management, making it possible to add degrees to dollars; it doesn't care. But at least they've added more clip art over the years.


Some algebraic calculators repeat the last operation. In the early days it was a hack to wire the "=" key to an external switch and enter 0+1=; the external switch would repeat the "+1" to work as a digital counter. If the number was the circumference of a wheel on a bike, for example, it was an odometer.

So, algebraic is 2*2 = = = = =, less strokes than the suggested RPN method.

Anyone wanting to make their eyes water on the subject of calculation needs to read 'What Every Computer Scientist Should Know About Floating-Point Arithmetic' by David Goldberg. One version appears here: http://docs.oracle.com/cd/E19957-01/806-3568/ncg_g...

RE: Calculator Input

I always enjoyed cascio calculators. They seem a bit more user friendly than the Texas Instruments.

RE: Calculator Input

>>>Some algebraic calculators repeat the last operation. In the early days it was a hack to wire the "=" key to an external switch and enter 0+1=; the external switch would repeat the "+1" to work as a digital counter. If the number was the circumference of a wheel on a bike, for example, it was an odometer.

So, algebraic is 2*2 = = = = =, less strokes than the suggested RPN method.<<<

I will concede that that saves a keystroke over the equivalent way to do that using RPN...something I didn't think possible. However, having said that, that's not the reason I load the registers with a constant. I do it to multiply a string of numbers by said constant. That is, type in the constant, hit enter three times and from then on it's simply number, x, clear, as often as needed. Which, incidental, absent mistyping a number is the only time the clear key is ever used; it superfluous otherwise.

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