CODEWITHSUNDEEP
rggplot2
seancarmody
seancarmody

Reputation: 6290

Change default colour for size legend

I would like to know whether it is possible to change the default (black) colour for a ggplot size legend when there is also a colour scale being used.

Here is an (artificial) reproducible example:

ggplot(diamonds, aes(x=x, y=price, colour=color, size=depth)) + geom_point()

The dots for the size (depth) legend are all black. If I wasn't also using colour as an aesthetic, I could make all the points a particular colour and the size legend would match that colour. But what if colour is an aesthetic?

Any suggestions?

Upvotes: 1

Views: 1321

Answers (1)

bdemarest
bdemarest

Reputation: 14667

Use the guides() function. I find the usage a bit difficult, but there are good examples here: http://cloud.github.com/downloads/hadley/ggplot2/guide-col.pdf.

ggplot(diamonds, aes(x=x, y=price, colour=color, size=depth)) + 
geom_point() + 
guides(size=guide_legend(override.aes=list(colour="steelblue")))

enter image description here

Upvotes: 5

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