This set of geoms makes it possible to connect points using straight lines.
Before you think
ggplot2::geom_path(), these functions have some additional tricks
up their sleeves. geom_link connects two points in the same way as
ggplot2::geom_segment() but does so by interpolating multiple
points between the two. An additional column called index is added to the
data with a sequential progression of the interpolated points. This can be
used to map color or size to the direction of the link. geom_link2 uses the
same syntax as
ggplot2::geom_path() but interpolates between the
aesthetics given by each row in the data.
stat_link( mapping = NULL, data = NULL, geom = "path", position = "identity", na.rm = FALSE, show.legend = NA, n = 100, inherit.aes = TRUE, ... ) stat_link2( mapping = NULL, data = NULL, geom = "path_interpolate", position = "identity", na.rm = FALSE, show.legend = NA, n = 100, inherit.aes = TRUE, ... ) geom_link( mapping = NULL, data = NULL, stat = "link", position = "identity", arrow = NULL, lineend = "butt", na.rm = FALSE, show.legend = NA, inherit.aes = TRUE, n = 100, ... ) geom_link2( mapping = NULL, data = NULL, stat = "link2", position = "identity", arrow = NULL, lineend = "butt", na.rm = FALSE, show.legend = NA, inherit.aes = TRUE, n = 100, ... ) geom_link0( mapping = NULL, data = NULL, stat = "identity", position = "identity", ..., arrow = NULL, arrow.fill = NULL, lineend = "butt", linejoin = "round", na.rm = FALSE, show.legend = NA, inherit.aes = TRUE )
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
The data to be displayed in this layer. There are three options:
NULL, the default, the data is inherited from the plot
data as specified in the call to
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.
function will be called with a single argument,
the plot data. The return value must be a
will be used as the layer data. A
function can be created
~ head(.x, 10)).
The geometric object to use to display the data, either as a
Geom subclass or as a string naming the geom stripped of the
geom_ prefix (e.g.
"point" rather than
Position adjustment, either as a string naming the adjustment
"jitter" to use
position_jitter), or the result of a call to a
position adjustment function. Use the latter if you need to change the
settings of the adjustment.
FALSE, the default, missing values are removed with
a warning. If
TRUE, missing values are silently removed.
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
The number of points to create for each segment
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.
Other arguments passed on to
layer(). These are
often aesthetics, used to set an aesthetic to a fixed value, like
colour = "red" or
size = 3. They may also be parameters
to the paired geom/stat.
The statistical transformation to use on the data for this
layer, either as a
Geom subclass or as a string naming the
stat stripped of the
stat_ prefix (e.g.
"count" rather than
Arrow specification, as created by
Line end style (round, butt, square).
fill colour to use for the arrow head (if closed).
Line join style (round, mitre, bevel).
geom_link understand the following aesthetics (required aesthetics are in bold):
geom_link2 understand the following aesthetics (required aesthetics are in bold):
The interpolated point coordinates
The progression along the interpolation mapped between 0 and 1
# Lets make some data lines <- data.frame( x = c(5, 12, 15, 9, 6), y = c(17, 20, 4, 15, 5), xend = c(19, 17, 2, 9, 5), yend = c(10, 18, 7, 12, 1), width = c(1, 10, 6, 2, 3), colour = letters[1:5] ) ggplot(lines) + geom_link(aes(x = x, y = y, xend = xend, yend = yend, colour = colour, alpha = stat(index), size = after_stat(index))) ggplot(lines) + geom_link2(aes(x = x, y = y, colour = colour, size = width, group = 1), lineend = 'round', n = 500) # geom_link0 is simply an alias for geom_segment to put the link geoms in # line with the other line geoms with multiple versions. `index` is not # available here ggplot(lines) + geom_link0(aes(x = x, y = y, xend = xend, yend = yend, colour = colour))