How can I change the font size of the labels in corrplot's lengend, in R?

Question

I would like to change the size of the 1 to -1 labels in the scale that appears alongside a call to corrplot , but am unsure what parameter to pass to accomplish this.

An example call would look like

corrplot(data, method="pie", cex=2)

Some reasonable guesses on my part, which did not work, include:

cex=2 (errors/warnings, no effect)
cex.xlab=2 (errors/warnings, no effect)
cex.legend=2 (errors/warnings, no effect)
cex.axis=2 (sets axis labels of main plot 2x size, no effect on legend text)

Answer 1

I think you're looking for tl.cex:

df <- data.frame(x = rnorm(10), y = rnorm(10), z = rnorm(10))

library(corrplot)
z <- corrplot(cor(df), method = "pie", tl.cex=4)

It looks like many of the options in corrplot() are set with tl*, eg, tl.col for color, etc.

Answer 2

Following on @ulfelder's answer, the parameters for controlling the scale are given by cl.x, rather than tl.x.

cl.cex = 2 does exactly what is needed.