Changing a font style in ggcorplot-CodePudding

Is there a way to change a font style for correlation shown in a correlation plot created using ggcorplot? I understand one can change the size and color of correlation, but I am having difficulty finding out a solution to change a font style.

e.g., correlation between drat and mpg is 0.7 and I would like to change 0.7 into a different font styl (e.g., from Arial to Times New Roman).

library(ggcorrplot)

# Compute a correlation matrix
data(mtcars)
corr <- round(cor(mtcars), 1)

# Compute a matrix of correlation p-values
p.mat <- cor_pmat(mtcars)

# Compute a plot
ggcorrplot(corr,
           hc.order = TRUE,
           type = "lower",
           lab = TRUE)

The resulting plot looks like this:

CodePudding user response：

One option would be to do some hacks or manipulations on the ggplot object returned by ggcorrplot, i.e. you could override the default mapping used by the geom_text layer (which is the second layer) which add the text label, e.g. below I use an ifelse to set the fontface to "bold" for drat and mpg and "plain" otherwise:

library(ggcorrplot)
#> Loading required package: ggplot2

data(mtcars)
corr <- round(cor(mtcars), 1)

p <- ggcorrplot(corr,
  hc.order = TRUE,
  type = "lower",
  lab = TRUE
)

p$layers[[2]]$mapping <- aes(Var1, Var2,
  fontface = ifelse(Var2 == "mpg" & Var1 == "drat", "bold", "plain")
)

p