8 Arranging plots
The grammar presented in ggplot2 is concerned with creating single plots. While the faceting system provides the means to produce several subplots all of these are part of the same main visualization, sharing layers, data, and scales. However, it is often necessary to use multiple disparate plots to tell a story or make an argument. These can of course be created individually and assembled in a layout program, but it is beneficial to do this in code to avoid time consuming and non-reproducible manual labor. A range of packages have risen to the occasion and provide different approaches to arranging separate plots. While this chapter will focus on the patchwork package you may also find some of the same functionalities in the cowplot, gridExtra and ggpubr packages.
This chapter will be split into two parts. The first will be concerned with arranging plots side by side with no overlap, while the second will be concerned with arranging plots on top of each other. While these two scenarios are not necessarily in opposition to each other, the former scenario will often benefit from functionality that makes little sense in the latter, e.g. alignment of plotting regions.