stat_center: Centers and spreads for bivariate data

In gggda: A 'ggplot2' Extension for Geometric Data Analysis

Centers and spreads for bivariate data

Description

Centers and spreads for bivariate data

Usage

stat_center(
  mapping = NULL,
  data = NULL,
  geom = "point",
  position = "identity",
  show.legend = NA,
  inherit.aes = TRUE,
  ...,
  fun.data = NULL,
  fun = NULL,
  fun.center = NULL,
  fun.min = NULL,
  fun.max = NULL,
  fun.ord = NULL,
  fun.args = list()
)

stat_star(
  mapping = NULL,
  data = NULL,
  geom = "segment",
  position = "identity",
  show.legend = NA,
  inherit.aes = TRUE,
  ...,
  fun.data = NULL,
  fun = NULL,
  fun.center = NULL,
  fun.ord = NULL,
  fun.args = list()
)

Arguments

mapping	Set of aesthetic mappings created by aes(). If specified and inherit.aes = TRUE (the default), it is combined with the default mapping at the top level of the plot. You must supply mapping if there is no plot mapping.
data	The data to be displayed in this layer. There are three options: If NULL, the default, the data is inherited from the plot data as specified in the call to ggplot(). A data.frame, or other object, will override the plot data. All objects will be fortified to produce a data frame. See fortify() for which variables will be created. A function will be called with a single argument, the plot data. The return value must be a data.frame, and will be used as the layer data. A function can be created from a formula (e.g. ~ head(.x, 10)).
geom	The geometric object to use to display the data for this layer. When using a ⁠stat_*()⁠ function to construct a layer, the geom argument can be used to override the default coupling between stats and geoms. The geom argument accepts the following: A Geom ggproto subclass, for example GeomPoint. A string naming the geom. To give the geom as a string, strip the function name of the geom_ prefix. For example, to use geom_point(), give the geom as "point". For more information and other ways to specify the geom, see the layer geom documentation.
position	A position adjustment to use on the data for this layer. This can be used in various ways, including to prevent overplotting and improving the display. The position argument accepts the following: The result of calling a position function, such as position_jitter(). This method allows for passing extra arguments to the position. A string naming the position adjustment. To give the position as a string, strip the function name of the position_ prefix. For example, to use position_jitter(), give the position as "jitter". For more information and other ways to specify the position, see the layer position documentation.
show.legend	logical. Should this layer be included in the legends? NA, the default, includes if any aesthetics are mapped. FALSE never includes, and TRUE always includes. It can also be a named logical vector to finely select the aesthetics to display. To include legend keys for all levels, even when no data exists, use TRUE. If NA, all levels are shown in legend, but unobserved levels are omitted.
inherit.aes	If FALSE, overrides the default aesthetics, rather than combining with them. This is most useful for helper functions that define both data and aesthetics and shouldn't inherit behaviour from the default plot specification, e.g. annotation_borders().
...	Additional arguments passed to ggplot2::layer().
fun.data	A function that is given the complete data and should return a data frame with variables ymin, y, and ymax.
fun.center	Deprecated alias to fun.
fun.min, fun, fun.max	Alternatively, supply three individual functions that are each passed a vector of values and should return a single number.
fun.ord	Alternatively to the ggplot2::stat_summary_bin() parameters, supply a summary function that takes a matrix as input and returns a named column summary vector. Overridden by fun.data and fun, cannot be used together with fun.min and fun.max.
fun.args	Optional additional arguments passed on to the functions.

Value

A ggproto layer.

Multidimensional position aesthetics

This statistical transformation is compatible with the convenience function aes_coord().

Some transformations (e.g. stat_center()) commute with projection to the lower (1 or 2)-dimensional biplot space. If they detect aesthetics of the form ⁠..coord[0-9]+⁠, then ..coord1 and ..coord2 are converted to x and y while any remaining are ignored.

Other transformations (e.g. stat_spantree()) yield different results in a lower-dimensional biplot when they are computed before versus after projection. If the stat layer detects these aesthetics, then the transformation is performed before projection, and the results in the first two dimensions are returned as x and y.

A small number of transformations (stat_rule()) are incompatible with these aesthetics but will accept aes_coord() without warning.

Computed variables

These are calculated during the statistical transformation and can be accessed with delayed evaluation.

⁠xmin,ymin,xmax,ymax⁠

results of ⁠fun.min,fun.max⁠ applied to ⁠x,y⁠

See Also

Other stat layers: stat_bagplot(), stat_chull(), stat_cone(), stat_depth(), stat_rule(), stat_scale(), stat_spantree()

Examples

ggplot(mpg, aes(x = displ, y = cty, shape = drv)) +
  geom_point() +
  stat_center(fun = "median", size = 5, alpha = .5)

ggplot(mpg, aes(x = displ, y = cty, shape = drv, linetype = drv)) +
  stat_center(size = 3) +
  stat_star()

gggda documentation built on July 18, 2026, 5:07 p.m.