How can we make xkcd style graphs?

Question

Apparently, folk have figured out how to make xkcd style graphs in Mathematica and in LaTeX. Can we do it in R? Ggplot2-ers? A geom_xkcd and/or theme_xkcd?

I guess i

Answer 1

Here's an attempt at the fonts, based on links from the xkcd forums and the extrafont package:

As noted above there is a forum discussion about fonts on the xkcd site: I grabbed the first one I could find, there may be other (better?) options (@jebyrnes posts another source for possible fonts in comments above -- the TTF file is here; someone reported a 404 error for that source, you might alternatively try here or here, substituting those URLs appropriately for xkcdFontURL below; you may have to work a bit harder to retrieve the Github-posted links)

   xkcdFontURL <- "http://simonsoftware.se/other/xkcd.ttf"
   download.file(xkcdFontURL,dest="xkcd.ttf",mode="wb")

(This is for quickie, one-off use: for regular use you should put it in some standard system font directory.)

   library(extrafont)

The most useful information about fonts was on the extrafont github site -- this is taken from there

font_import(".")   ## because we downloaded to working directory
loadfonts()

Example taken more or less verbatim from the github site:

library(ggplot2)
p <- ggplot(mtcars, aes(x=wt, y=mpg)) + geom_point() +
  ggtitle("Fuel Efficiency of 32 Cars") +
  xlab("Weight (x1000 lb)") + ylab("Miles per Gallon") +
  theme(text=element_text(size=16, family="xkcd"))

ggsave("xkcd_ggplot.pdf", plot=p,  width=4, height=4)
## needed for Windows:
##   Sys.setenv(R_GSCMD = "C:/Program Files/gs/gs9.05/bin/gswin32c.exe")
embed_fonts("xkcd_ggplot.pdf")

Answer 2

Thinking along the same line as some of the other answers, I've "un-ggplotted" the chart and also added on the flexibility of the x-axis label locations (which seems to be common in xkcd) and an arbitrary label on the chart.

Note that I had a few issues with loading the Humor Sans font and manually downloaded it to working directory.

And the code...

library(ggplot2)
library(extrafont)

### Already have read in fonts (see previous answer on how to do this)
loadfonts()

### Set up the trial dataset 
data <- NULL
data$x <- seq(1, 10, 0.1)
data$y1 <- sin(data$x)
data$y2 <- cos(data$x)
data$xaxis <- -1.5

data <- as.data.frame(data)

### XKCD theme
theme_xkcd <- theme(
    panel.background = element_rect(fill="white"), 
    axis.ticks = element_line(colour=NA),
    panel.grid = element_line(colour="white"),
    axis.text.y = element_text(colour=NA), 
    axis.text.x = element_text(colour="black"),
    text = element_text(size=16, family="Humor Sans")
    )

 ### Plot the chart
 p <- ggplot(data=data, aes(x=x, y=y1))+
      geom_line(aes(y=y2), position="jitter")+
      geom_line(colour="white", size=3, position="jitter")+
      geom_line(colour="red", size=1, position="jitter")+
      geom_text(family="Humor Sans", x=6, y=-1.2, label="A SIN AND COS CURVE")+
      geom_line(aes(y=xaxis), position = position_jitter(h = 0.005), colour="black")+
      scale_x_continuous(breaks=c(2, 5, 6, 9), 
      labels = c("YARD", "STEPS", "DOOR", "INSIDE"))+labs(x="", y="")+
      theme_xkcd

ggsave("xkcd_ggplot.jpg", plot=p, width=8, height=5)

Answer 3

Here is my take on the lines with ggplot2 using some of the code from above:

ggplot()+geom_line(aes(x=seq(0,1,length.out=1000),y=sin(x)),position=position_jitter(width=0.02),lwd=1.5,col="white")+
  geom_line(aes(x=seq(0,1,length.out=1000),y=sin(x)),position=position_jitter(width=0.004),lwd=1.4,col="red")+
  geom_line(aes(x=seq(0,1,length.out=1000),y=cos(x)),position=position_jitter(width=0.02),lwd=1.5,col="white")+
  geom_line(aes(x=seq(0,1,length.out=1000),y=cos(x)),position=position_jitter(width=0.004),lwd=1.4,col="blue")+
  theme_bw()+theme(panel.grid.major=element_blank(),panel.grid.minor=element_blank())

Not sure how to replace the axes, but could use the same approach with jitter. Then it's a matter of importing the font from XKCD and layering with geom_text.

Answer 4

You might want to consider the following package:

Package xkcd: Plotting ggplot2 graphics in a XKCD style.

library(xkcd)
vignette("xkcd-intro")

Some examples (Scatterplots, Bar Charts):

• Scatterplot:

• Bar Chart:

Answer 5

Basic line-drawing function:

xkcd_line <- function(x, y, color) {
  len <- length(x);
  rg <- par("usr");
  yjitter <- (rg[4] - rg[3]) / 1000;
  xjitter <- (rg[2] - rg[1]) / 1000;
  x_mod <- x + rnorm(len) * xjitter;
  y_mod <- y + rnorm(len) * yjitter;
  lines(x_mod, y_mod, col='white', lwd=10);
  lines(x_mod, y_mod, col=color, lwd=5);
}

Basic axis:

xkcd_axis <- function() {
  rg <- par("usr");
  yaxis <- 1:100 / 100 * (rg[4] - rg[3]) + rg[3];
  xaxis <- 1:100 / 100 * (rg[2] - rg[1]) + rg[1];
  xkcd_line(1:100 * 0 + rg[1] + (rg[2]-rg[1])/100, yaxis,'black')
  xkcd_line(xaxis, 1:100 * 0 + rg[3] + (rg[4]-rg[3])/100, 'black')
}

And sample code:

data <- data.frame(x=1:100)
data$one <- exp(-((data$x - 50)/10)^2)
data$two <- sin(data$x/10)
plot.new()
plot.window(
    c(min(data$x),max(data$x)),
    c(min(c(data$one,data$two)),max(c(data$one,data$two))))
xkcd_axis()
xkcd_line(data$x, data$one, 'red')
xkcd_line(data$x, data$two, 'blue')

Produces:

Answer 6

This is a very, very rough start and only covers (partially) the hand-drawn look and feel of the lines. It would take a little bit of work to automate this but adding some AR(1) noise to the response function could make it seem slightly hand drawn

set.seed(551)
x <- seq(0, 1, length.out = 1000)
y <- sin(x)

imperfect <- arima.sim(n = length(y), model = list(ar = c(.9999)))
imperfect <- scale(imperfect)
z <- y + imperfect*.005
plot(x, z, type = "l", col = "blue", lwd = 2)