## Saturday, August 23, 2014

### General Calculator Advice for School (and Possibly Beyond)

General Calculator Advice for School (and Possibly Beyond)

Last week, I received several emails that ask me to make recommendations for which calculators to purchase. Today I will outline my general thoughts about calculators.

Note: I will assume that tablets, such as the Microsoft Surface and Apple iPad are not allowed in classroom tests. Therefore, the focus of this blog entry will be on physical, tangible calculators and not calculator apps found on tablets and phones.

Non-Graphing Calculators

Today's non-graphing scientific calculators are packed with features. The high-end models include:

* numerical derivatives and numerical integration calculations
* textbook input and output, which includes fractions, exact expressions of π, and exact roots
* a general root finder, along with solvers for two simultaneous equations, three simultaneous equations, quadratic equations, and cubic equations
* statistics with regression analysis
* basic matrix operations (determinant, inverse)
* table generator of a function f(x)
* decimal, binary, hexadecimal, and octal conversions
* a library of conversions and constants (all vary)

If you are interested in obtaining a non-graphing calculator and aim to get the most for your money, I recommend any of the following models. Links of my review are listed below:

Texas Instruments TI-36X Pro
http://edspi31415.blogspot.com/2011/04/ti-36-pro-review.html

Casio fx-115ES Plus
http://edspi31415.blogspot.com/2012/04/review-casio-fx-115-es-plus-review.html

Cannon F-792SGA
http://edspi31415.blogspot.com/2014/05/review-canon-f-792sga-scientific.html

Sharp EL-W516X
http://edspi31415.blogspot.com/2011/09/sharp-el-w516x-review.html

All are solar powered (partially) and that extends the life of the battery. Each can be obtained for approximately \$16 - \$20, although some office stores do sell the TI-36X as high as \$25. The differences between each of the calculators are fairly minor. The interface of the TI-36X has more integrated interface than the others, that is, you will not need to go into separate modes to use matrices and complex numbers. Other than that, any of the four listed above is a solid choice.

The non-graphing calculator that is not solar is the HP 35s from Hewlett Packard. What separates the HP 35s from the others listed is:

* The HP 35s is programmable. Each program is a list of keystrokes. The 35s has about 32,000 bytes of memory.
* The 35s operates in both algebraic and RPN (Reverse Polish Notation) modes. The algebraic mode is not textbook entry.
* Complex number support includes powers, trigonometric functions, exponential functions, and logarithmic functions.
* The factorial function (x!) accepts any real number, not just positive integers.
* The 35s runs on batteries (two CR 2032 batteries)
* The 35s is typically priced in the \$50 - \$60 range.

Solvers on the 35s include simulteanous equations of order 2 and 3, and a general root finder. Numerical integrals are included.

Graphing Calculators

Most students will probably use a graphing calculator sometime during their studies. Here are some of my thoughts:

TI-83 Plus vs TI-84 Plus: I lean towards the TI-84 Plus simply because it has a faster processor, the display is crisper, and the TI-84 Plus offers textbook entry and output mode (known as MathPrint).

Programming wise, they have 24,000 bytes of RAM. Fortunately, they have a lot more of flash ROM memory which acts like archived storage. (512,000 bytes for the 83 Plus vs 1 MB for the 84 Plus). The archived storage contains programs and calculator applications.

Retail wise, the difference in price is about \$10. The 83 Plus costs about \$90 retail versus \$100 for the 84 Plus.

TI-84 Plus vs TI-84 Plus C Silver Edition: A question of color. Back to school time is a best time to find the TI-84 Plus C Silver Edition at its best price, which normally is about \$120 to \$140.

My review of the color edition is here:
http://edspi31415.blogspot.com/2013/04/ti-84-plus-c-silver-edition-review.html

Basically, while the color and the rechargeable battery are good additional features, processing sometimes suffers. Other not so good points about the TI-84 C Silver Edition is that the graphing screen is smaller, and we only have 21,000 bytes of RAM to work with.

Of these two, I have to give the edge to the older, monochrome displayed TI 84 Plus.

I personally would not recommend the TI nSpire CX unless you get the CAS edition. I will talk about calculators with CAS in the next edition.

Casio may be cheaper, but is it better? I believe the Casio calculators can go toe to toe with the Texas Instruments counterparts. The user interface is comparable if not easier, and you can mix graph types (function, parametric, and polar) on one graphing screen. All three models I am about to describe have 62,000 bytes of programmable memory and uses a menu and soft key interface. Basically, if you can operate one, you should be easily be able to handle the others.

No worries about whether the teacher can operate a Casio, I recently have seen the Casio models fly off the shelves (at least in the eastern Los Angeles area).

fx-9750G II: This is the basic model, priced around \$50. All input and output is algebraic (no textbook input or output). Otherwise, it may be something to consider if you don't want to spend much money or not a fan of math and just need a graphing calculator to get by. I don't have an fx-9750G II - yet and interested in adding this to my collection.

fx-9860G II: This has all the features of the fx-9750G II plus a geometry app, spreadsheet app, textbook input and output (MathIO), backlit screen, and Flash ROM memory. Price typically range from \$75 to \$90.

fx-CG 10 (fx-CG 20 outside of the United States), better known as the Prizm: This is the fx-9860G II but with color and higher Flash ROM memory. The screen on the Prizm is awesome. Priced about \$100.

Prizm vs TI-84 Plus C Silver Edition: Prizm is my choice, hands down.

My choices for recommendations would be: TI-84 Plus (classic monochrome), Casio Prizm.

If you are on a budget and textbook input and output is not a must have, you may want to consider the Casio fx-9750G II.

Calculators with CAS

This class is the upper echelon of calculators, those with a CAS (computer algebraic system). I would only recommend that you consider buying a calculator with CAS if any of the following apply:

* You are in college and plan to obtain a degree in mathematics, engineering, or physics.
* You are planning to take multi-variable calculus, differential equations, and any math classes beyond this level.
* You are a mathematics enthusiast.

Models to consider are these:

Hewlett Packard: HP 50g. I would consider this the standard when it comes to calculators with a CAS. Features include an equation writer, RPN mode, matrix entry mode, multi variable solver, solver templates for general equations, polynomials, and simultaneous equations, and 3D graphing. The 50g has an SD card slot. RPN mode truly shines with the 50g. The current price is about \$100.

Hewlett Packard: HP Prime: This is HP's color graphing calculator. I think this has the fastest processor of any calcualtor. The memory is 32 MB, which is a ton. The calculator also has a touch screen, which allows for cursor placement and zooming on graphs. It is powered with a rechargeable battery. Check out the Advanced Graphing app where it is easy to execute implicit plots and open statements. (For example x^2 + y^2 <= 4). The downside is that the RPN mode is very limited. The current price is around \$150.

Three other calculators with CAS to consider are:

Texas Instruments: TI nSpire CX CAS: This does not have a touch screen but has a touchpad. I really like the geometry app on this model. Like the Prime, the CX CAS has a color screen and has a rechargeable battery. The user interface is like Microsoft Office, files are created for each project. My biggest gripe about the nSpire is the programming is severely limited and can only interact with home pages. Price is about \$150.

Texas Instruments TI-89 Titanium: I would rank this calculator higher except that the screen kind of sucks. The font is tiny and there is little contrast to the screen. Feature wise, then TI-89 is the most advanced of all Texas Instruments calculators, despite the latest operating system was release in 2005. Price is about \$150.

Casio ClassPad fx-CP400: I don't have the newest ClassPad, but from what I read it is an upgrade to the ClassPad 330. The screen is large, the keyboard is limited, you do mostly everything with a stylus, and the screen rotated. I think the price is about \$150.

My recommendations for calculators with a CAS are the HP 50g and HP Prime. Search my blog for basic programming tutorials for both the HP 50g (RPL Programming Tutorial) and HP Prime.

Hope this helps, and if you have questions, please ask and I will try the best I can to assist. Many thanks for the comments and questions.

Eddie

This blog is property of Edward Shore. 2014