Preface

On New Year’s Day, 2015, the gnuplot development team released version 5.0—the first major new gnuplot release in over 10 years! I decided to take this opportunity to bring Gnuplot in Action up to date and to cover all the new features gnuplot has acquired since the first edition of this book was written (in 2007).

It quickly became apparent it wouldn’t be sufficient to just add a couple of chapters explaining the new features. In fact, the book you’re reading now has been almost entirely rewritten from scratch. Most of the material from the first edition has been retained, but it’s been heavily rearranged to accommodate the addition of new topics and to reflect the changes in my own understanding and priorities.

Gnuplot 5 is largely backward compatible with previous versions, and hence most of the first edition remains valid. At the same time, new features have been added to all parts of gnuplot, either to add new functionality or to streamline and improve the existing usage. Although many of the new features are small by themselves, when taken together, their cumulative effect leads to a significantly different, more sophisticated user experience.

In the process, the book’s page count has increased substantially from the first edition. To keep the physical dimensions of the printed book in check without having to sacrifice important and useful material, some topics of a more specialized nature have been relegated to the electronic (e-book) version. Access to the e-book is included in the purchase of a print copy of the book.

Today, gnuplot is still going strong. Despite increased competition, gnuplot’s two most attractive features are still largely unmet by other tools:

• The ability to explore data graphically, with an absolute minimum of effort, protocol, overhead, or boilerplate
• The ability to create immaculate, very high-quality graphs, with text labels and other decorations, for presentation purposes

What’s new is that gnuplot has arrived in the 21st century. Color is now the standard, font handling is up to date, and the graphing backend makes use of all contemporary technologies to create the best-looking graphs possible.

In the first edition, I wrote that gnuplot was “an indispensable part of my toolbox: one of the handful of programs I can’t do without.” Several years on, this is still true.