Microsoft's Excel spreadsheet creates pretty good charts and graphs. But when I need to plot data on a map or superimpose three x axes on a graph, Excel runs out of gas. In these instances, it makes no sense to buy powerful and expensive math software just for its visual presentation capabilities. So, I draw maps, charts and graphs by hand.
Recently, I got a copy of “Visualizing Data,” by Ben Fry and published by O'Reilly Media ($39.99). Fry aims to give readers techniques that turn sets of raw data into meaningful and useful images. He starts by explaining seven steps — acquire, parse, filter, mine, represent, refine and interact — that lead readers on a systematic path to better understand the information they have and how they want to display it. But don't expect ready-to-use examples you can employ right away. If you simply want a fancier chart for next week's engineering review, stick with Excel.
In this book, you will learn how to use Processing, a language Fry developed to manipulate information and create visual displays. This free Java-based language gives users great control over how they use and display data, but without the need to purchase graphics libraries or become programming experts. The author notes some programming experience with Java or C++ will help in latter chapters, though. But don't worry; you won't have to master a complex API. Commands such as shape, vertex, stroke, fill and point do the job.
Although examples emphasize the use of the Processing language, Fry always strives to make readers pay attention to how they want to analyze information and he helps them answer their basic question, “How do I present x, y and z so they make sense?”
Fry provides sample data sets on a website (http://rbi.ims.ca/5704-534) so you don't have to create test data to use with code examples. Sadly, the site lacks an index, so you can't poke around and browse through other examples or sample code. Lack of an index seems like a major oversight for a work about presenting visual information. The book promises examples on the O'Reilly website, too, but as of late January, none existed. So, if you use the book's examples, you face a lot of typing.
In addition to Fry's book, I recommend the second edition of “The Visual Display of Quantitative Information,” a book by Edward R. Tufte (Graphics Press, $40). This excellent book will change your ideas about how you use graphics to express complicated information. Tufte's many examples show the good and bad of graphs and charts and how people can use graphics to clearly and simply represent information so others can better comprehend it.
“Visualizing Data” at O'Reilly Media: http://rbi.ims.ca/5704-535
Edward R. Tufte's website: http://rbi.ims.ca/5704-536