` COMPUTE! ISSUE 151 / APRIL 1993 / PAGE 118`

 DeltaGraph Professional for Windows. (presentation software) (Software Review) (Evaluation) by Charles Idol The impact on your audience of any presentation or document dealing with data increases greatly if you use graphs or charts to illustrate your message. A computer is most helpful in preparing these graphics, and there are many graphing programs on the market. But I've never seen one which even comes close to the scope and power of DeltaGraph Professional for Windows. We're all familiar with line and column and bar and stacked bar and pie charts, but those are just the beginning of this program's repertoire. Its 2-D options include charts I'd never heard of. A bubble chart, for instance, is a clever way of plotting three parameters on two axes. Suppose you had a set of data on a population giving height and weight and the number of people with those characteristics. A bubble chart could use height and weight as the x-axis and y-axis, and plot a circle, or bubble, for each data point centered at the proper point, but with the radius of the circle determined by the number of people. To keep the circle radii within bounds, the program uses logarithmic scaling and presents a scale of the radii. Different populations could appear on the same chart by the use of different bubble colors. Novel and striking. Another chart new to me is the spider chart. This time, suppose you had a set of data on the quality of the water at three different locations, with measurements of a number of constituents such as iron, chlorine, calcium, and so on. The spider chart would have a spoke for each constituent and would plot a point on that spoke for each location. The program connects the points for each location and fills the area defined with a different color for the different locations. The effect is dramatic. The list of charts goes on and on, with 40 different types and 80 subtypes. In 2-D, you can have stacked pie, multiple pie, area, time line, contour line, contour fill, ternary (triangle), polar, and many more, including hierarchy (organizational) charts. If 3-D turns you on, you can have column, ribbon, area, wireframe, surface line, surface fill, X-Y-Z scatter, and more. Even further, if you don't like the view of your 3-D charts, you can rotate them to suit yourself. For scientific users, DeltaGraph offers six standard curve-fitting routines plus a user-defined option, error bar options, superscripted and subscripted text, and log-log and semi-log axis scaling. The program helps you prepare a slide show, including a stand-alone version, and even includes a spelling checker for the text in your charts. Import capability is extensive. For data, you can import from Data Interchange, dBase, Excel, Harvard Graphics, Lotus 1-2-3, and Quattro, and export using the Windows OLE and DDE functions. For graphics, you can import from all the popular formats, including AutoCAD DXF and WordPerfect WPG, and export in a number of formats. DeltaGraph supports both PostScript and Graphics Device Interface (GDI) printing, so you can send your files to a wide range of output devices. PostScript devices include some film recorders and any black-and-white or color laser printer that supports PostScript. GDI devices include all dot-matrix printers; any non-PostScript laser printer; ink-jet, thermal wax, and color GDI printers; plotters; and most film recorders. You can also print a program file directly to disk, creating a PostScript file you can send to a service bureau for printing to a Linotronic or other high-resolution imagesetter. Program documentation is thorough, with an inch-thick user's manual. The manual includes a brief tutorial; while this doesn't take you through all the options by any means, it suffices to familiarize you with the program features sufficiently that you can explore the other capabilities on your own. With all this power, it's not surprising that the program is voracious in RAM and disk space. The literature is a little misleading in its recommendation of 4MB of RAM and 8MB of hard disk space. To load all the bells and whistles that DeltaGraph offers, you must have 18MB of disk space available. This is a most impressive program. It left me and others with feelings of admiration and awe. If you have a need for high-quality presentation graphics, DeltaGraph Professional for Windows will not only fill your requirements but also probably suggest some striking creative object modes.