Format labels produced by cut() as percentages

Question

I need to apply cut on a continuous variable to show it with a Brewer color scale in ggplot2, as in Setting breakpoints for data with scale_fill_brewer() function i

Answer 1

A new answer to an oldish question.

You could use the label argument to pass a function to format the labels. I will use gsubfn and scales::percent

library(gsubfn)
library(scales)
pcut <- function(x) gsubfn('\\d\\.\\d+', function(x) percent(as.numeric(x)),xx)
d <- data.frame(x=runif(100))

ggplot(d,aes(x=x,y=seq_along(x))) + 
 geom_point(aes(colour = cut(x, breaks = 10))) + 
 scale_colour_brewer(name = 'x', palette = 'Spectral', label = pcut)