Sigmaplot 4.1.

Jandel Scientific, Corte Madera, CA 94925.

System requirements: MS DOS 2.0 or later, 485K of RAM, hard drive, and graphics adapter (VGA recommended).

Price: $495.

Depending on where you plan to publish, the way in which you present the data can be almost as important as what you present. Jandel Scientific has recently updated their scientific graphing program called Sigmaplot[R] 4.1, which can greatly facilitate the presentation of data. Sigmaplot[R] is a remarkable graphics package that offers flexibility, with power and precision, to develop stylish, presentation-quality scientific graphs that can be incorporated into either a visual presentation or a manuscript destined for publication.

Sigmaplot[R] requires an IBM[R] PC or compatible computer with at least 485K of RAM and a graphics adapter such as CGA, EGA, VGA, or Hercules. The program supports most laser printers, including the new Hewlett Packard LiserJet III and Postscript printers. The number of built-in fonts is limited, but the program does contain a variety of Greek and math characters. It will support additional Bitstream printer fonts, which may be purchased separately from Jandel. Sigmaplot[R] can be operated with or without a mouse; however, a mouse is preferable for navigating efficiently through the various drop-down menus. The program is disk intensive and uses slightly less than 3.5M of hard-disk storage. Jandel indicates that Siginaplot[R] can run under Windows 3 with adequate memory installed. Sigmaplot[R] can also be used with Novell, 3-Com, and many DOS-compatible networks.

The graphing package was evaluated for this review using a 16-mHz IBM[R] AT-compatible computer running DOS 5.0 with a standard monochrome (paper white) VGA monitor. Installation and configuration of Sigmaplot[R] on the hard drive was simple. It was as easy as placing the Install disk into drive A, typing "install," and answering a few questions about the configuration of the computer system.

Sigmaplot[R] produces striking, two-dimensional pie charts and x-y graphs including scatter and line graphs, bar graphs, and box plots. The x-y graphs can be scaled using linear, log, semi-log, log-log, probability, logit, or probit axes. Gmphs can be resized, overlaid, and moved by simply clicking and moving the mouse. Up to 10 graphs can be configured on a page. An important feature often lacking in many graphics programs is the ability to plot error bars and confidence intervals. Sigmaplot[R] admirably performs this task using supplied values or values derived from internal calculations. In addition, the program includes an extremely powerful transformation language and curve-fitting capability as well as some statistical analysis functions.

Data can be entered from the keyboard into a spreadsheet or by importing from other Sigmaplot[R] graph files (.SPG), Lotus 1-2-3 and compatible files (.WKS, WK1), .DIF, and ASCII text files. The Sigmaplot[R] data spreadsheet supports up to 16,000 columns wide and 65,000 rows long.

Text labeling is also very easy with Sigmaplot[R]. Text can be placed anywhere on the page, and editing functions are user friendly. To resize text, for example, one would click on the appropriate label while in text editing mode, then press the numeric +" or " - " key to increase or decrease size. The up and down arrow keys invoke superscript and subscript, respectively. Boxes, circles, and ellipses are available for enclosing remarks, tides, or legends.

Sigmaplot[R] documentation is readable and comprehensive. Not only is there an easy "Get Started" section of the manual, but Jandel also includes a separate "Beginners Guide" that allows one to make simple plots in 5 minutes. More complicated graphs such as plots of mathematical functions, curve-fits, and polynomials require more in-depth reading of the extensive, but well laid out, manual. Limited but useful "Help" screens are available for each menu component and are accessed by pressing the shot-thand F1 key.

I could find very few weaknesses with this program. The manual's index is somewhat limited, but the on-line "Help" screens are usually sufficient to accomplish most things a user might want to do. The program is logically laid out, and the menu interface is sufficiently intuitive so that the program is not overly cumbersome for routine use, considering the complexity and power of the plotting program. The program should be considered for use more in research applications and the preparation of scientific and technical graphics than for routine physical therapy practice.

Kennon Francis, PhD

The Univ of Alabama at Birmingham

Birmingham, Ala