Nothing
ggplot.multistats currently provides stat_summaries_hex and some helpers.
stat_summaries_hex is similar to ggplot2::stat_summary_hex,
but allows specifying multiple stats using the funs parameter (see Example).
ggplot.multistats is on CRAN.
install.packages('ggplot.multistats')
You can also install the development version from GitHub:
# install.packages('devtools')
devtools::install_github('flying-sheep/ggplot.multistats')
Specify a summary variable using the z aesthetic
and specify a list of funs to provide after_stats for you:
library(ggplot2)
library(ggplot.multistats)
ggplot(iris, aes(Sepal.Width, Sepal.Length)) +
stat_summaries_hex(
aes(z = Petal.Width, fill = after_stat(median), alpha = after_stat(n)),
funs = c('median', n = 'length'),
bins = 5
)

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