ggplot2 Time Series Heatmaps

April 15, 2012

(This article was first published on MarginTale, and kindly contributed to R-bloggers)

How do you easily get beautiful calendar heatmaps of time series in ggplot2? E.g:

From MarginTale

I was impressed by the lattice-based  implementation from Paul Bleicher of Humedica, which you can find referenced in Then, when other blogs like picked up the topic, I decided to try a ggplot2 implementation. In a comment to the above Revolution Analytics post, Hadley already presented a quick ggplot rendition, upon which I build here.

How do you attack the problem? Looking at the example output above:
  1. We facet_grid by “months” and “years” 
  2. The data itself is plotted by “week of month” and “day of week” and coloured according to the value of interest
So, given a time series we just have to fiddle with time indexes to create a data.frame containing the time series as well as per observation the corresponding “month”, “year”, “week of month”, “day of week”. The rest is then a one-liner of code with Hadley’s wonderful ggplot2 system.

The following code contains step by step comments:

It should be easy to wrap into a function and I hope its useful.

To leave a comment for the author, please follow the link and comment on their blog: MarginTale. 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.


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)