Corner Labels in ggplot2

Question

I\'m interested in trying to create simple corner labels for a multipanel figure I am preparing in ggplot. This is similar to this previously asked question, but the answers

Answer 1

Two recent changes have made this a lot easier:

• The latest release of ggplot2 has added the tag caption which can be used to label subplots.
• The package patchwork makes it really easy to plot multiple ggplot objects. https://github.com/thomasp85/patchwork

This means that no altering of grobs is required. Adapting the reproducible example provided by Kev:

library(ggplot2)
# install.package("patchwork")
library(patchwork)

a <- 1:20
b <- sample(a, 20)
c <- sample(b, 20)
d <- sample(c, 20)
mydata   <- data.frame(a, b, c, d)

myplot1  <- ggplot(mydata, aes(x=a, y=b)) + geom_point() + labs(tag = "A")
myplot2  <- ggplot(mydata, aes(x=b, y=c)) + geom_point() + labs(tag = "B")
myplot3  <- ggplot(mydata, aes(x=c, y=d)) + geom_point() + labs(tag = "C")
myplot4  <- ggplot(mydata, aes(x=d, y=a)) + geom_point() + labs(tag = "D")

myplot1 + myplot2 + myplot3 + myplot4