Add an extra point to a single facet in ggplot-CodePudding

I want to add a single point to only one facet. I tried to set the group in geom_point:

ggplot(data=mpg, aes(displ, hwy))  
  geom_point()  
  facet_wrap(~class)   geom_point(aes(x=5, y=25, group = "pickup"), colour="blue")

But that put a blue dot in all facets. Is there any way to constrain the point to only one?

CodePudding user response：

You could achieve your desired result by putting the information for your point in a dataframe which you pass to the data argument of your second geom_point:

library(ggplot2)

ggplot(data=mpg, aes(displ, hwy))  
  geom_point()  
  facet_wrap(~class)   
  geom_point(data = data.frame(displ = 5, hwy = 25, class = "pickup"), colour="blue")