Chapter 7. All about axes
This chapter covers
In this chapter, we finally come to coordinate axes and their labeling. Treating them last, after discussing plot styles and decorations, may seem surprising, given how critical well-labeled coordinate axes are to achieving an informative graph. On the other hand, gnuplot’s default behavior for axes-related options is perfectly adequate in almost all situations, so that explicit customization is rarely required.
One topic deserves special consideration, namely, the use of multiple axes on the same plot, and this is what we’ll discuss first. Then we move on and describe all the ways that axes and their labels can be customized. Lastly, we treat the special case when one axis (usually the x axis) represents time, in other words, when the plot shows a time series. Time series plots pose special challenges, since now the labels aren’t simply numeric. Instead, we need to worry about things such as the names of months and weekdays, potentially in different languages, too! This has long been a problem to gnuplot users, and so I’ll devote significant space to this application.
But first, let’s talk about multiple axes on the same plot.