0 0 This pocket-sized piece of brainpower can turn you into a mental giant the power to the head of the class. the rate of chemical reactions or the present value of an annuity, a hand- held calculator will-in a myriad of ways -give you the edge. Instead of laboring over time-con- suming calculations, you can focus on what you're learning and let your cal- culator do the computing. Then, too, a calculator allows you to explore complicated problems you wouldn't dare undertake without it. For example, with some of the new- est hand-held models, you can enter formulas from, say, an economics text, and the calculator then takes over, solving for the equation's variables. The advantage: Even if you can't do the math, you can work with the results of the computations. And, since many calculators have unit- conversion capability, you won't have to lug around heavy reference books to look up, for example, how many grams are in a pound. Broadly speaking, calculators are categorized as business (financial) units or scientific (technical) models. Facts on Financial Calculators Financial calculators - geared for students in business, finance, and eco- nomics-should include, at a mini- mum, the following functions: time value of money, amortization, bond yield and price, and internal rate of re- turn. Some dedicated financial units also have one-variable and two-vari- able statistical functions, currency rate conversion, and even a time-and-ap- pointment feature. And for repetitive calculations, you can easily program the machine and later execute the pro- gram with a touch of a button. The advanced financial models have lots of permanent storage, allowing you to save everything you've done. On one model, says Bill Wickes, software project manager at Hewlett-Packard, you can even print out your results us- ing a cordless printer activated by an in- frared light beam. Programmed for Problem-Solving Scientific or technical calculators serve students of math, engineering, physics, chemistry, premed, and data processing. These units perform as many as 200 different scientific and mathematical functions: reciprocals, complex numbers, and the like. In ad- dition, there are statistical functions, including mean, standard deviations, and normal distributions. But the heart-and-soul of these cal- culators is their programmability. "In the 'hard' sciences," says Wickes, "the problems are so varied that it's impossible to provide a prepro- grammed key for every situation." This type of calculator, therefore, serves as a tool box, from which stu- dents select the tools they need for each specific application. Math students and teachers alike are raving about one of the most ad- vanced scientific models, which allows the user to do calculations involving symbols and matrices- in effect, solv- ing many of the problems found in ele- mentary calculus. These problems can now be presented graphically on the multi-line displays that are common in the newest models. What handy devices, these hand- held calculators. You'll work faster, smarter, and with fewer errors. Don't be caught empty-handed. O Calculating Your Choices eep these guidelines in mind when purchasing a calculator: * Suit your own needs. As with any other purchase, be sure first to identify your specific needs and then look for the particular model that fills them. Social science ma- jors can probably get by with the basic statistical functions, while en- gineering majors need program- mable calculators with a full range of functions. Ask students who have just taken the course what cal- culator they found useful. " Decide on the power source. Hand-held calculators are either battery-powered or solar-powered. Some batteries can be recharged; others must be replaced every year or so. Solar units require a light source sufficient to power the solar cells, so be sure the solar calculator you buy will work in the light level that will be available. " Take a good look at the display. Most calculators now have a liquid crystal display (LCD). The display should be easily read, even in rela- tively dim light (such as when the overhead projector is on during a lecture). And remember, you may be looking at that tiny screen for long periods of time. " Try out the keypad. Are the keys easy to press without error? Do you like the touch? " Consider durability. How much wear and tear will this calculator have to take? Does the manufac- turer have a reputation for building rugged calculators? Do you need one that's encased in a hard pack, which provides maximum protec- tion? Or is a simple vinyl covering sufficient? * Check the warranty. Your calcu- lator should have at least a one-year warranty, and for a more advanced model you may want to buy a ser- vice contract. I EA B ASS Stop the world- I want to log on! It's a new campus game called "Dial- ing for Data" - all you need is a com- puter, a telephone, and a little thing called a modem. Get those three gadgets working in your corner, and you have a world by the tail.... a world of information. With a little help from your elec- tronic "friends," you can: " Research a term paper after the li- brary shuts down. " Hunt for a job. 14 plus/FALL 88 AT. yOURf Serylce " "Download" free computer soft- ware. * "Log on" to more than 3,000 data bases - computer files of information on everything from agriculture to zoo management. " Engage in electronic debates (via "bulletin boards") on politics, nu- clear power, etc. * Mull over the late-breaking finan- cial news. " Take a college course offered 1,000 miles away. ILLUSTRATION BY JULIE KOTAR ILLUSTRATION BY TIM WALKER FALL 88/plus 11