How do I adapt my ggplot code in order to change the default colours used in the chart produced?

Question

I do not like the colors in my chart that the code below produces.

How do I adapt the code, in order to change the array of colors used within the chart?

ggplot(Rating, aes(x = Function, y = Freq, fill = Rating)) + 
  ggtitle("Test")  + 
  labs(x="Function", y = "Rating") +
  geom_col() +
  theme_bw()

Hello Jed, welcom to SO. You will certainly attract more people to look at your question, if you deliver a [minimal, reproducible example](https://stackoverflow.com/questions/5963269/how-to-make-a-great-r-reproducible-example/5963610#5963610). You will find solutions to your question at many places, one could be [here](http://www.sthda.com/english/wiki/ggplot2-colors-how-to-change-colors-automatically-and-manually) — MarBlo, Jul 18 '20 at 11:31
You might find it useful to look at the `scale_fill_*()` functions, for example `scale_fill_distiller()`. — teunbrand, Jul 18 '20 at 11:31

score 2 · Accepted Answer · answered Jul 18 '20 at 14:48

This is quite a general question, so there are quite a few answers, here. Generally, you change the colors used in the plot via one of the scale_*_** functions, where * is the aesthetic (color, fill, etc), and ** is the type or method for creating the scale. Some of these include:

manual for manually defining stuff
brewer to use one of the predefined Brewer color palettes
discrete for discrete scales
gradient, gradient2 or gradientn to define color gradients (you give some set number of colors and a gradient is created to apply to a continuous variable for the aesthetic).
viridis to use the viridis scales. There are discrete and continuous versions here, so you typically need to specify
and many others... like distiller, fermenter, and various others that come with RColorBrewer.

Here's some examples below to get you started. Here's a default plot:

p <- ggplot(mtcars, aes(x=factor(carb), y=mpg)) + geom_col(aes(fill=factor(carb)))
p

Example applying one of the Brewer scales:

p + scale_fill_brewer(palette='Set1')

Example using a viridis scale:

p + scale_fill_viridis_d()

Example using a manually-defined scale: Note here you specify using scale_fill_manual(values=...). The values= argument must be sent a vector or list of colors which are at least the same number as the number of levels for your variable assigned to the fill= aesthetic. You can also pass a named vector to explicitly define which color is applied to individual factor levels. Here I'm just showing you the lovely colors of the rainbow:

p + scale_fill_manual(values=rainbow(6))

How do I adapt my ggplot code in order to change the default colours used in the chart produced?

1 Answers1