patchwork: nice package for assembling plots from ggplot2

https://github.com/thomasp85/patchwork https://www.r-bloggers.com/patchwork-r-package-goes-nerd-viral/

p1 + p2

Can also combine ggplots and base plots: https://patchwork.data-imaginist.com/articles/guides/assembly.html

p1 + ~plot(mtcars$mpg, mtcars$disp, main = 'Plot 2')