#### Overview of this book

gnuplot is the world's finest technical plotting software, used by scientists, engineers, and others for many years. It is in constant development and runs on practically every operating system, and can produce output in almost any format. The quality of its 3d plots is unmatched and its ability to be incorporated into computer programs and document preparation systems is excellent. gnuplot Cookbook ñ it will help you master gnuplot. Start using gnuplot immediately to solve your problems in data analysis and presentation. Quickly find a visual example of the graph you want to make and see a complete, working script for producing it. Learn how to use the new features in gnuplot 4.4. Find clearly explained, working examples of using gnuplot with LaTeX and with your own computer programming language. You will master all the ins and outs of gnuplot through gnuplot Cookbook. You will learn to plot basic 2d to complex 3d plots, annotate from simple labels to equations, integrate from simple scripts to full documents and computer progams. You will be taught to annotate graphs with equations and symbols that match the style of the rest of your text, thus creating a seamless, professional document. You will be guided to create a web page with an interactive graph, and add graphical output to your simulation or numerical analysis program. Start using all of gnuplot's simple to complex features to suit your needs, without studying its 200 page manual through this Cookbook.
gnuplot Cookbook
Credits
www.PacktPub.com
Preface
Free Chapter
Plotting Curves, Boxes, Points, and more
Annotating with Labels and Legends
Applying Colors and Styles
Combining Multiple Plots
Programming gnuplot and Dealing with Data
The Third Dimension
Using and Making Graphical User Interfaces
Surveying Special Topics
Finding Help and Information
Index

## Breaking an axis

Sometimes we would like to plot something over two disjoint domains, but want the plot to be contained in a single graph. In this case, we need to indicate that there is a discontinuity in the axis and generate two separate sets of tic marks, as shown in the following figure:

### How to do it…

The following gnuplot script will produce the previous figure. It is provided with this book as a file called `breaking_an_axis.gnuplot`. Run it with gnuplot breaking_an_axis.gnuplot to get a PNG file that should look just like the previous figure. If you don't have the pngcairo terminal installed, you can use the png terminal or anything you wish, but you may get a different pattern in the vertical box. Type `test` at the gnuplot interactive prompt after setting your terminal (and output file if you are not using an interactive terminal) to see a list of the available patterns.

```set term pngcairo font "Times,8"
set out "plot.png"
set border 2
set zeroaxis lt -1
set ytics axis nomirror
set xtics...```