ggplot2 色盲 ggthemes 除了黑色

Question

I want to create a general line of code I can apply to any ggplot<\/code> grouped barchart I make. I want it to make my graphs colour blind friendly. In the library ggthemes<\/code> , the scale_fill_colorblind<\/code> function does just the job. My problem is that black is often picked as one of the colours; I sometimes need to overlay confidence intervals and other stuff, so black is not really an option.

library(ggplot2)
library(ggthemes)
ggplot(diamonds, aes(clarity, fill=cut)) + geom_bar(position="dodge")+
scale_fill_colorblind()

Answer 1

at best a hack,

ggthemes_data$colorblind  <- ggthemes_data$colorblind[-1]
assignInNamespace("ggthemes_data", ggthemes_data, ns="ggthemes")

last_plot() + scale_fill_colorblind()

Answer 2

Another option is use scale_fill_manual with ggthemes::colorblind_pal .

library(ggplot2)
library(ggthemes)
ggplot(diamonds, aes(clarity, fill = cut)) + 
  geom_bar(position = "dodge") +
  scale_fill_colorblind()


n <- length(unique(diamonds$cut))

# or 
n <- data.table::uniqueN(diamonds$cut)

# Manually fill the geom with breaks provided by the data
#  and getting one extra color from ggthemes::colorblind_pal
#  then dropping black (the first color)
ggplot(diamonds, aes(clarity, fill = cut)) + 
  geom_bar(position = "dodge") +
  scale_fill_manual(breaks = diamonds$cut, 
                    values = colorblind_pal()(n + 1)[-1])

Answer 3

This answer builds on the answer from Alec but creates a function that returns scale_fill_discrete<\/code> with a type argument equal to a vector of the last 7 colors used by scale_fill_colorblind<\/code> . You do not have to specify the number of groups in your data; if there are N groups, scale_fill_discrete<\/code> will use the first N colors in its type<\/code> argument. The function I wrote will also let you select which colors you want, so you can drop black or use the 2nd, 4th, and 5th colors.