I am trying to understand how to map 2D to 3D using ggplot() and eventually plot_gg(). I am, however, stuck on understanding how to express the third variable to be mapped. This example:
ggdiamonds = ggplot(diamonds, aes(x, depth)) +
stat_density_2d(aes(fill = stat(nlevel)),
geom = "polygon", n = 100, bins = 10,contour = TRUE) +
facet_wrap(clarity~.) +
scale_fill_viridis_c(option = "A")
uses a variable nlevel that I now understand is calculated during the building of the ggplot but I have not figured out from where it is calculated or how to specify a variable of my choosing.
Does anyone have a good reference for understanding how to specify this variable? Most examples on the 'net seem to use the same dataset but do not specify this particular aspect...