Reversing default scale gradient ggplot2

?scale_colour_gradient shows the default values of low = "#132B43" and high = "#56B1F7".

Simply switch those around:

ggplot(faithfuld, aes(waiting, eruptions)) +
    geom_raster(aes(fill = density)) +
    scale_fill_continuous(high = "#132B43", low = "#56B1F7")

enter image description here

Personally, I think this is less intuitive than the default.


Alternatively, you can use a reverse scale, but this will also flip the legend to start at the top:

ggplot(faithfuld, aes(waiting, eruptions)) +
    geom_raster(aes(fill = density)) +
    scale_fill_continuous(trans = 'reverse')

enter image description here


you can use the color palettes from RColorBrewer(link) library and assign the direction of the color gradient

library(RColorBrewer)
library(ggplot2)

ggplot(df, aes(x, y)) +
  geom_tile(aes(fill = z, width = w), colour = "grey50") +
  scale_fill_distiller(palette ="RdBu", direction = -1) # or direction=1


# data
  df <- data.frame( x = rep(c(2, 5, 7, 9, 12), 2),
                    y = rep(c(1, 2), each = 5),
                    z = rep(1:5, each = 2),
                    w = rep(diff(c(0, 4, 6, 8, 10, 14)), 2))

enter image description here