具有固定截止值的连续缩放填充渐变 R

Question

I can't figure out how to define fixed cutoffs in a gradient fill. This is an example on the iris data:

ggplot(iris, aes(x=Sepal.Length,
                 y=Sepal.Width,
                 fill=Petal.Length))+
  geom_point(shape=21)+
  scale_fill_gradientn(colors=c("white","black","darkred","red"))

In my actual data, I have a heatmap with many values 0, a lot between 1-10, a few outliers in the hundreds and thousands.

I would like the gradient to be:

• 0 = white
• 1-10 = from gray to black
• 11-100 = from black to darkred
• 101-1000 = from darkred to red
• over 1000 = purple

I don't want to transform it in a factor with bins, because I do want to maintain the continuous gradient especially at the low parts of the scale.

Thank you for you help

Answer 1

You will have to generate you own color pal with colorspace for the white to red, but if you're okay with the default blues or viridis, you can have that out of the box with scale_fill_binned() :

ggplot(iris, aes(x=Sepal.Length,
                 y=Sepal.Width,
                 fill=Petal.Length))+
  geom_point(shape = 21, size = 4) +
  scale_fill_binned(breaks = c(2, 5), type = "viridis")

https://ggplot2.tidyverse.org/reference/guide_coloursteps.html