Question

In a linetype scale, how do I skip certain values for my graph? Value 2 and 3 look too similar for my taste, so I’d like to skip one of them and instead use 0, 1, 2 and 4.

Answer 1

You could use scale_linetype_manual() and set values.

 df=data.frame(x=rnorm(100),y=rnorm(100),group=rep(c("a","b","c","d"),each=25))

 ggplot(df,aes(x,y,group=group))+
   geom_line(aes(linetype=group))+
   scale_linetype_manual(values=c(6,1,2,4))