Count overlapping points

mark_count() collapses coincident (x, y) observations to one point sized by how many fall there (ggplot2's geom_count() / stat_sum()) — the honest way to show overplotting on a discrete or rounded grid. size defaults to after_stat(n) (the overlap count); map it to after_stat(prop) for the proportion instead.

Usage

mark_count(plot, ..., blend = NULL, sketch = NULL, data = NULL)

Arguments

plot

A PlotSpec (from vplot()).

...

Encodings (tidy-eval): x, y (+ color/fill to count within groups, and size to override the default after_stat(n)).

blend

Optional blend mode for compositing this layer against what is already drawn beneath it (the panel and earlier layers), one of the CSS mix-blend-mode names, e.g. "multiply", "screen", "darken". The whole layer composites as one isolated group (not per element).

sketch

A sketch() spec giving this layer a hand-drawn look (wobbly outlines, hachure fills), NA/FALSE to force it crisp (overriding a plot-wide theme_sketch()), or NULL (default) to inherit. Geometry marks accept it; text, raster, hex and datashade marks do not.

data

Optional layer data frame; overrides the plot data for this layer.

Value

The modified PlotSpec.

Examples

vplot(mpg <- data.frame(cyl = mtcars$cyl, gear = mtcars$gear)) |>
  mark_count(x = cyl, y = gear)