fast_plot_density

library(extrafont)
download.file("http://simonsoftware.se/other/xkcd.ttf",
              dest="xkcd.ttf", mode="wb")
system("mkdir ~/.fonts")
system("cp xkcd.ttf  ~/.fonts")
font_import(paths = "~/.fonts", pattern="[X/x]kcd")
fonts()
loadfonts()

ggplot(data.frame(x = c(0, 1)), aes(x = x)) +
  stat_function(fun = dnorm, args = list(0.25, 0.1),
                aes(colour = "Group 1"), size = 1.5) +
  stat_function(fun = dnorm, args = list(0.7, 0.1),
                aes(colour = "Group 2"), size = 1.5) +
  scale_x_continuous(name = "Probability",
                     breaks = seq(0, 1, 0.2),
                     limits=c(0, 1)) +
  scale_y_continuous(limits = c(0.01,4), name = "Frequency") +
  ggtitle("Normal function curves of probabilities") +
  scale_colour_brewer(palette="Set1") +
  labs(colour = "Groups") +
  theme(axis.line = element_line(size=1, colour = "black"),
        panel.grid.major = element_blank(),
        panel.grid.minor = element_blank(),
        panel.border = element_blank(),
        panel.background = element_blank(),
        plot.title=element_text(size = 20, family="xkcd-Regular"),
        text=element_text(size = 16, family="xkcd-Regular"),
        axis.text.x=element_text(colour="black", size = 12),
        axis.text.y=element_text(colour="black", size = 12))