Useful functions for ggplot2

library("grid")
library("ggplot2")
library("ggfun")

element_roundrect

The element_roundrect works like element_rect to draw round rectangle background. We can use it to adjust theme elements, including legend, strip, panel and plot background.

p <- ggplot(mpg, aes(displ, cty)) + geom_point()
p <- p + facet_grid(cols = vars(cyl))
p <- p + theme(strip.background=element_roundrect(fill="grey40", color=NA, r=0.15))
p

p2 <- ggplot(mtcars, aes(mpg, disp, color=factor(cyl), size=cyl)) +
         geom_point()
p2 + theme(legend.background=element_roundrect(color="#808080", linetype=2))

gglegend

p <- ggplot(mtcars, aes(mpg, disp)) + geom_point()
data <- data.frame(colour = c("red",  "blue"), VALUE = c("A", "B"))
gglegend(aes(colour = VALUE, label=VALUE), data, geom_text, p)

set_font

d <- data.frame(x=rnorm(10), y=rnorm(10), lab=LETTERS[1:10])
p <- ggplot(d, aes(x, y)) + geom_text(aes(label=lab), size=5)
set_font(p, family="Times", fontface="italic", color='firebrick')