An Example Usage of ggplot_add()

November 7, 2017

A generic function ggplot_add() was added to ggplot2 by this PR: Allow addition of custom objects by thomasp85 · Pull Request #2309 · tidyverse/ggplot2 I think creating a custom Geom or Stat and its constructor (geom_*() or stat_*()) is enough for the most of the extension packages of ggplot2, but some people, including me, need this. Why are there no geom_highlight()? Here is an example code of my package gghighlight: ... Read more

Introduction to gghighlight: Highlight ggplot's Lines and Points with Predicates

October 6, 2017

Suppose we have a data that has too many series like this: set.seed(2) d <- purrr::map_dfr( letters, ~ data.frame(idx = 1:400, value = cumsum(runif(400, -1, 1)), type = ., stringsAsFactors = FALSE)) For such data, it is almost impossible to identify a series by its colour as their differences are so subtle. library(ggplot2) ggplot(d) + geom_line(aes(idx, value, colour = type)) Highlight lines with ggplot2 + dplyr So, I am motivated to filter data and map colour only on that, using dplyr: ... Read more