View Full Version : Computer driven programable calculator

09-04-2003, 06:35 AM
My calculator is programable TI-86. For those of you not familar with this type of calculator it does just about anything, and if it don't do it you can program it.

I've got programs on mine where it will convert feet and inches to decimal form and programs that will add these figures and programs that run the base/rise/slope formulas. These programs are interactive with each other. In other words the TI-86 is a fantastic tool that I use all the time.

The problem is, as you may have noticed, is that ocasionally I leave it at home. It never fails on days that I leave it at home I need it at work for some complex calculations.

What I would like to find is some way to run custom math programs on my computer at work. I want something that is not diffucult to use, but is fairly flexable.


09-04-2003, 06:48 AM
I've got programs on mine where it will convert feet and inches to decimal form

foist of all ... you need metric.

and "b" is. . . you can do it all in excel.

09-04-2003, 08:06 AM
How about MatLab? I think that most engineers use it to do lots of stuff. Or you could build your formula in Exel. It's a pretty powerful program for building complex equations.


Matt J.
09-04-2003, 08:06 AM
Popeye... you're right. Metric makes somuch more sense. Shame we can't (won't) switch.

Chad. Get an HP. Those TI's are child's play next to even the old HP 48SX, let alone the newer 48GX. smile.gif The polish numeric functions are quick to learn, and are actually easier once you get it straight. Programs for the HP do anything... I even heard there's one that'll do celestial navigation and DR, though I can't find it.

09-04-2003, 08:18 AM
Back in the 70's when the HP-46 came out...the technical manual was little more than a pamphlet. It wasn't long before that manual greww a hundred fold...and not by HP but by inquisitive engineers, and the celestial programs were part of that...find an old manual...and I can't even use a TI calculator, it just doesn't talk right...after cutting my teeth on the first production run of the reverse polish notation machines.....also you can program the things to leave messages using the led displays, countdown timers and a gazillion other fun things....

09-04-2003, 09:17 AM
Visual basic with activeX controls lets you build a real live gui screen that looks just like a calculator. worth learning if you have the time.

or quick and dirty route is excel, can fancy it up a bit with screens and macros.

"reverse polish logic"? can someone tell me how to set my oven timer. soon as i read the line in the manual, lift my eyes back to the oven control, the damn PLC flips off and i don't get time to enter the start time... i mean faaaaaak.

Bruce Hooke
09-04-2003, 09:23 AM
I'll second the recommendation on Excel. I used to use a programmable HP calculator for this sort of stuff but now I almost always use Excel. One of the cool things about Excel is that you can have lots of potential inputs (variables) but you only need to re-enter the ones that changed since the last time. I have a spreadsheet setup that will allow me to calculate the angle (azumith) and altitude of the sun at any time for any location on earth (not including annual variations). I have another workbook that handles basic beam calculations. You could set up one workbook with most of the routine calculations you use and just keep it open in the background on your computer.

That said, for relatively simple stuff like converting feet and inches to decimals I think a calculator would be quicker just because you can punch in numbers faster...

09-04-2003, 10:06 AM
Okay this sounds good so far. Here is an example of how my calculator converts standard to decimal.

You input for example 16'-2 1/2" like this: 16.0208. This is stored in memory (Y). The program takes the interger of this and stores in another memory location (X). The fraction part is multiplied by 100 and stored in yet another location (W). The interger of that is divided by 12 and stored elsewhere (V). The fraction part of (W) is than multiplied by 100 and divided by 192 and stored in (U). Once all this is done it adds X+U+V to get the decimal version of the number.

Sounds complicated don't it. But it ain't that bad. This is one of my base programs that the others use. I can start my Base/Slope program by inputing my entry 16'-2 1/2" as 16.0208 and it runs the conversion program and than runs the base/slope program. It than takes the decimal answer and runs it through the Decimal to standard program and displays my answer in FT and Inches.

Now this is not to confuse you, but it shows how each program is inter-active with the next program. Can I do this with excell?


09-04-2003, 10:09 AM
Didn't someone post a link a while back that allowed you to download a program that emulated an HP calculator on your computer?

Keith Wilson
09-04-2003, 10:14 AM
Yes, you can do that in Excel You can also do it to a whole pile of numbers at once and print out the result in a spiffy table, if you're so inclined. I do a lot of not very complex calculations at work, and although I love my HP RPN calculator, I find I almost never use it anymore. I use Excel for any calculations involving formulas or the same operation on multiple numbers, and a freeware HP emulator on-screen calcuator for one or two calculations. What I do isn't usually complicated enough to require a specialized math program.

09-04-2003, 11:06 AM
All the emulators that I found require a ROM download from the calculator itself. I don't have the hardware that is required to do this (even though my calculator is capable).

I'm slightly experienced with excell. I've used it for some enginering problems, but could sure use some advice and pointers on setting this up.


Matt Middleton
09-04-2003, 11:13 AM
I'll chime in with a vote for Excel. I used it quite a bit in college for performing all types of functions- what you described would be very straightforward to do in Excel. Explore the program, it won't take you very long to pick it up, and you can rewrite your programs pretty easily into Excel for when you forget the TI.

Oh, and don't let anyone badmouth the TI- I got through engineering school with no trouble using my TI-85. ;)

Matt J.
09-04-2003, 11:27 AM
TI's are for architects and wussies (that oughta get someone going ;) )

I got the engineering school, two license exams, and months of land surveying using my HP as a data collector so tongue.gif . Try that with a TI.

(tongue in cheek :D ).

[ 09-04-2003, 12:27 PM: Message edited by: Matt Joyce ]

Matt Middleton
09-04-2003, 11:28 AM
Hey Chad- we cross posted. Check your email.


09-04-2003, 12:04 PM
Matt, got your e-mail and will download it and play around with it. Thanks

Sorry to confuse you Donn. Yes 16'-2 1/2" has a decimal equivelant of 16.2083. Now the TI-86 takes input in decimal form so you kinda have to trick it. To put in 16' 2 1/2" you break it down like this:

16 = 16'
.02 = 2"
.0008 = 1/2" or 8/16"

It than uses the interger and fraction functions to break the decimal up into the three different parts (feet, inches, and fractions of an inch) and works equations for each part and than adds them back together to get your final decimal answer.

Sounds confusing huh? Just wait till you try and get that back to a standard format from decimal (which I've programed my calculator to do). :D


ps Matt Joyce we will just ignore that remark for now. ;)

The reason I got the TI is that is what the school required for the courses I was taking. I had tried to use a calculator that they didn't recomend before and it was just to much trouble trying to take their programs and making them work on my calculator.

09-04-2003, 12:09 PM
Donn 192 is the amount of 1/16" that are in a foot. Thus in the case of 1/2" which is (8) sixtenths you would divided 8 by 192 to get the decimal equivlant of 1/2".


Dave R
09-04-2003, 12:11 PM
Chad, check your e-mail.

09-04-2003, 12:19 PM
ahh yes, there we have it. the standard system of measurement based on body parts. heaven help us rene descartes.

Matt Middleton
09-04-2003, 12:23 PM
Hey Matt Joyce-

Well mt TI can ... uh

Well once when ... um.


Well you just give me a day or two, and I'll come up with something!! tongue.gif tongue.gif ;)

09-04-2003, 12:25 PM
Both Dave's and Matt's work.

Matt's allows for input in one cell just the way I input in my calculator

Dave's on the other hand use 2 cells and inputs it more of the way that you would actually read it and his also does the conversion back to standard format.

Now what we have to do is start with a simple program that will use these programs as references. It is basiclly pythogrems theorum (a^2 + b^2 = c^2). When inputing a & b in standard format it needs to reference back to standard to decimal conversion and than start working the problem. What it works out is the angle (45degrees or less), its realtionship to 12 (i.e. 12/5) and the length of c (which it will have to refrence back to convert from a decimal to a standard format).

It's not as difficult as it sounds and is rather usefull.


09-04-2003, 04:09 PM
What I need to know now is who to link routines. I know you can reference back to cells but I'm trying to figure is this what I want.


09-04-2003, 04:23 PM
I love confiscating TI's from students. None of them care about the calculating abilities. They just want a calculator that plays PONG. :rolleyes:

Chad...Why muddle about in the kiddie pool. Go get yourself a copy of Mathmatica and Stephen Wolfram's "New kind of Science." In 6 months you can post how Cellular Automaton taught you how to build a better boat!

Take Care.


09-04-2003, 04:38 PM
I recently thought it would be kind of neat to buy one of those whippy do graphing math programs and was quickly disuaded by their price of between $1,000 and $1,500 for a non-student copy!

Bruce Hooke
09-04-2003, 04:44 PM
As noted, you can link functions in Excel by simply referencing the appropriate cells from the new equation. If you need conditional linkages one option is to use one cell as the "switch" where the value in that cell determines what happens in other cells. An example would be:

=IF(D1=1,[what to do if cell D1 equals 1],[what to do if D1 doesn't equal 1, which could be another IF statement checking to see if D1=2, for example])

In your situation, where you might want to use the output from one function as the input for another function, but in other cases you might want to jump right into the second function with a manual input, you have at least a couple of options. One is to simply manually enter the output for one function into the cell that provides the input for the next function. Another option would be to set up the second function so that it first looks in it's input cell and if it doesn't find anything there then looks at the output for the other function. You will probably achieve maximum functionality if you DON'T try to stick too closely to the way you did things in the calculator. For example, on the calculator it makes sense to break things up into a lot of separate functions that you can link as needed. In Excel, if one function normally provides the input for another it may make sense to put them both on a sheet dedicated to the second function (basically merge the two functions). If you need the first function as an input for other functions then simply repeat it on other sheets.

If you have not really done much entering of complicated equations in Excel then try this to get started: open a blank Excel spreadsheet and select a cell for your first equation. Click on the '=' button at the top of the sheet. Select a function from the drop down list that appears to the left of the equals button. This will launch a wizard that will walk you through the selected function. Once you get to know a function you can skip the wizard but it is a big help for learning functions.

I suspect that once you get to know Excel you will never look back...

09-05-2003, 07:05 AM
So Bruce are saying instead of linking equations just included them in the formula each time you need them?