001、
library(ggplot2)
p<-ggplot(mtcars,aes(mpg,hp,colour=factor(cyl)))+geom_point()
p
p+theme(axis.line.x=element_line(linetype=1,color="black",size=0.3))+
annotate(geom = 'segment', y = Inf, yend = -Inf, color = 'green',
x = Inf, xend = Inf, size = 6) ## Inf无穷大， -Inf无穷小
。
标签：粗细,library,边框,单独,某条,ggplot2 From： https://www.cnblogs.com/liujiaxin2018/p/17574754.html