Display points and their range — geom_points

This geom is like ggplot2::geom_pointrange() in that it draws points and lines. However, unlike ggplot2::geom_pointrange(), this geom takes in sets of x-y points and calculates the ranges/intervals based on those. It then plots both the original points and the ranges using ggplot2::geom_linerange(). In cases where not all points are connected (because of grouping due to aesthetics), the background_line argument can be used to add lines that span the entire point range for each x or y category.

Usage

geom_points_range(
  mapping = NULL,
  data = NULL,
  stat = "points_range",
  position = "identity",
  ...,
  na.rm = FALSE,
  orientation = NA,
  background_line = NULL,
  show.legend = NA,
  inherit.aes = TRUE
)

stat_points_range(
  mapping = NULL,
  data = NULL,
  geom = "points_range",
  position = "identity",
  ...,
  na.rm = FALSE,
  orientation = NA,
  show.legend = NA,
  inherit.aes = TRUE
)

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)).

stat

The statistical transformation to use on the data for this layer. When using a geom_*() function to construct a layer, the stat argument can be used the override the default coupling between geoms and stats. The stat argument accepts the following:

A Stat ggproto subclass, for example StatCount.
A string naming the stat. To give the stat as a string, strip the function name of the stat_ prefix. For example, to use stat_count(), give the stat as "count".

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".

...

Arguments passed on to both ggplot2::geom_linerange() and ggplot2::geom_point().

na.rm

If FALSE, the default, missing values are removed with a warning. If TRUE, missing values are silently removed.

orientation

The orientation of the layer. The default (NA) automatically determines the orientation from the aesthetic mapping. In the rare event that this fails it can be given explicitly by setting orientation to either "x" or "y". See the Orientation section for more detail.

background_line

A named list of aesthetic values to use for plotted line segments that span the entire y or x range for each x or y category. The default aesthetics will be used for any aesthetics that are not specified in the list. This can be useful if the plotted groups of points don't overlap but you want a continuous line connecting all points for a given x or y category. If NULL (the default), no line segments will be plotted.

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.

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. borders().

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".

Aesthetics

geom_points_range() understands the following aesthetics (required aesthetics are in bold):

x
y
size
color/colour
fill
shape
alpha
group
linetype
linewidth

Computed variables

These are calculated by the 'stat' part of layers and can be accessed with delayed evaluation. stat_points_range() provides the following variables, some of which depend on the orientation:

after_stat(ymin) or after_stat(xmin)
the minimum extent of the point range
after_stat(ymax) or after_stat(xmax)
the maximum extent of the point range

Orientation

This geom treats each axis differently and, thus, can thus have two orientations. Often the orientation is easy to deduce from a combination of the given mappings and the types of positional scales in use. Thus, ggplot2 will by default try to guess which orientation the layer should have. Under rare circumstances, the orientation is ambiguous and guessing may fail. In that case the orientation can be specified directly using the orientation parameter, which can be either "x" or "y". The value gives the axis that the geom should run along, "x" being the default orientation you would expect for the geom.

Examples

library(ggplot2)
library(palaeoverse)
data(tetrapods)
tetrapod_names <- tetrapods$accepted_name[1:50]
beds_sampled <- sample.int(n = 10, size = 50, replace = TRUE)
occdf <- data.frame(taxon = tetrapod_names, bed = beds_sampled)
ggplot(occdf, aes(y = reorder(taxon, bed, min), x = bed)) +
  geom_points_range()