Images as x-axis labels (updated)

June 2, 2016
By

(This article was first published on R – Irregularly Scheduled Programming, and kindly contributed to R-bloggers)

They say “if you want to find an answer on the internet, just present a wrong one as fact. Then wait.

It didn’t take long, actually. Despite my searches while trying to get images into x-axis labels it seems I overlooked a working, significantly less hacky implementation. My Google-fu had in fact let me down.

Baptiste Auguié (@tpab / @baptiste) had this working a while ago (seemingly before the ggplot2 update that broke other methods), and in a definitively less hacky way. I’ve added a new gist (if you’re reading this on R-bloggers, the gist isn’t embedded, so either follow the link or view on my site) which implements it on the same graph as earlier, and I like this significantly more.

This method gets around the element_text() validation and updates the grobs in a way that’s above my pay grade/understanding of ggplot2 internals, and is a much more consistent way to go about it. This also:

  • places the factor labels on the graph along with the picture, covering some concerns about people not knowing which maps are for which country,
  • leaves room for the caption to go back in, which I wanted,
  • automatically scales the grob better,
  • doesn’t involve creating an external grob and thus turning off clipping; using axis.text.x is exactly what I was hoping for.
Updated version using @baptiste's method; much better.

Updated version using @baptiste’s method; much better.

My version worked (sort of) but only because it used options that were bad practice (not doubting that for a moment). I’d like to see this method make it into ggplot2 properly; Baptiste had an open GitHub issue involving it a while ago but it has since been closed, presumably without the feature being incorporated.

I started the previous post by saying how awesome open-source software is (e.g. R). You know what else is awesome? The #rstats community. Thank you to every one of you.

To leave a comment for the author, please follow the link and comment on their blog: R – Irregularly Scheduled Programming.

R-bloggers.com offers daily e-mail updates about R news and tutorials on topics such as: Data science, Big Data, R jobs, visualization (ggplot2, Boxplots, maps, animation), programming (RStudio, Sweave, LaTeX, SQL, Eclipse, git, hadoop, Web Scraping) statistics (regression, PCA, time series, trading) and more...



If you got this far, why not subscribe for updates from the site? Choose your flavor: e-mail, twitter, RSS, or facebook...

Comments are closed.

Sponsors

Never miss an update!
Subscribe to R-bloggers to receive
e-mails with the latest R posts.
(You will not see this message again.)

Click here to close (This popup will not appear again)