How do I print greek letters on the diagonal of a pairs plot in R?
r, symbols
Solution
`expression(lab)` doesn't actually evaluate `lab` so you end up with all the labels being `lab`. Instead, you could change that line to:
text(0.5, 0.5, parse(text=lab), cex=cex, font=font)
which will do what you want. Note that the `pairs` function also accepts a labels argument, so this would work too:
pairs(dat, labels=c(expression(alpha), expression(beta), expression(gamma)))
Problem
I want to create a pairs plot in R that has labels on the diagonal written as greek letters. I've tried creating a custom `text.panel` function that wraps the labels in an `expression()` call, but this does not work. Here is a simple test case: ``` pairs.greek <- function(x, ...) { panel.txt <- function(x, y, labels, cex, font, ...) { lab <- labels text(0.5, 0.5, expression(lab), cex=cex, font=font) } pairs(x, text.panel=panel.txt) } dat <- data.frame(alpha=runif(10), beta=runif(10), gamma=runif(10)) pairs.greek(dat) ```