R: Geom for drawing circles in the ggplot2 framework
GeomCircle
R Documentation
Geom for drawing circles in the ggplot2 framework
Description
Circles are drawn with a specified radius centered at (x, y).
This geom is very much exploratory - we are using it for drawing edges for self references.
It is not explored for any more general use, so use with caution!
Usage
GeomCircle
geom_circle(mapping = NULL, data = NULL, stat = "identity",
position = "identity", na.rm = FALSE, show.legend = NA,
inherit.aes = TRUE, radius = 0.05, ...)
Arguments
mapping
Set of aesthetic mappings created by aes or
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.
stat
The statistical transformation to use on the data for this
layer, as a string.
position
Position adjustment, either as a string, or the result of
a call to a position adjustment function.
na.rm
If FALSE (the default), removes missing values with
a warning. If TRUE silently removes missing values.
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.
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.
radius
numeric value giving the radius of the circle to be drawn (0-1 normalized scale)
...
other arguments passed on to layer. These are
often aesthetics, used to set an aesthetic to a fixed value, like
color = "red" or size = 3. They may also be parameters
to the paired geom/stat.
Format
An object of class GeomCircle (inherits from Geom, ggproto) of length 5.
Examples
# circles are drawn centered at x and y
library(ggplot2)
data(mpg)
ggplot(mpg, aes(displ, hwy)) + geom_circle(radius=0.1) + geom_point()
ggplot(mpg, aes(displ, hwy)) + geom_circle(linetype=2, radius=0.05, alpha=0.5)
ggplot(mpg, aes(displ, hwy)) + geom_circle(aes(linetype=factor(cyl)), radius=0.05, alpha=0.5)
providing 
.