Text geoms are useful for labeling plots. They can be used by themselves as
scatterplots or in combination with other geoms, for example, for labeling
points or for annotating the height of bars. geom_text()
adds only text
to the plot. geom_label()
draws a rectangle behind the text, making it
easier to read.
gf_text(
object = NULL,
gformula = NULL,
data = NULL,
...,
label,
alpha,
angle,
color,
family,
fontface,
group,
hjust,
lineheight,
size,
vjust,
parse = FALSE,
nudge_x = 0,
nudge_y = 0,
check_overlap = FALSE,
xlab,
ylab,
title,
subtitle,
caption,
geom = "text",
stat = "identity",
position = "nudge",
show.legend = NA,
show.help = NULL,
inherit = TRUE,
environment = parent.frame()
)
gf_label(
object = NULL,
gformula = NULL,
data = NULL,
...,
label,
alpha,
angle,
color,
family,
fontface,
group,
hjust,
vjust,
lineheight,
size,
parse,
nudge_x = 0,
nudge_y = 0,
label.padding = unit(0.25, "lines"),
label.r = unit(0.15, "lines"),
label.size = 0.25,
xlab,
ylab,
title,
subtitle,
caption,
stat = "identity",
position = "nudge",
show.legend = NA,
show.help = NULL,
inherit = TRUE,
environment = parent.frame()
)
When chaining, this holds an object produced in the earlier portions of the chain. Most users can safely ignore this argument. See details and examples.
A formula with shape y ~ x
.
Faceting can be achieved by including |
in the formula.
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)
).
Additional arguments. Typically these are
(a) ggplot2 aesthetics to be set with attribute = value
,
(b) ggplot2 aesthetics to be mapped with attribute = ~ expression
, or
(c) attributes of the layer as a whole, which are set with attribute = value
.
The text to be displayed.
Opacity (0 = invisible, 1 = opaque).
An angle for rotating the text.
A color or a formula used for mapping color.
A font family.
One of "plain"
, "bold"
, "italic"
, or "bold italic"
.
Used for grouping.
Numbers between 0 and 1 indicating how to justify text relative the the specified location.
Line height.
A numeric size or a formula used for mapping size.
If TRUE
, the labels will be parsed into expressions and
displayed as described in ?plotmath
.
Horizontal and vertical adjustment to nudge labels by.
Useful for offsetting text from points, particularly on discrete scales.
Cannot be jointly specified with position
.
If TRUE
, text that overlaps previous text in the
same layer will not be plotted. check_overlap
happens at draw time and in
the order of the data. Therefore data should be arranged by the label
column before calling geom_text()
. Note that this argument is not
supported by geom_label()
.
Label for x-axis. See also gf_labs()
.
Label for y-axis. See also gf_labs()
.
Title, sub-title, and caption for the plot.
See also gf_labs()
.
A character string naming the geom used to make the layer.
The statistical transformation to use on the data for this
layer, either as a ggproto
Geom
subclass or as a string naming the
stat stripped of the stat_
prefix (e.g. "count"
rather than
"stat_count"
)
Position adjustment, either as a string, or the result of
a call to a position adjustment function. Cannot be jointly specified with
nudge_x
or nudge_y
.
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.
If TRUE
, display some minimal help.
A logical indicating whether default attributes are inherited.
An environment in which to look for variables not found in data
.
Amount of padding around label. Defaults to 0.25 lines.
Radius of rounded corners. Defaults to 0.15 lines.
Size of label border, in mm.
a gg object
Positional attributes (a.k.a, aesthetics) are specified using the formula in gformula
.
Setting and mapping of additional attributes can be done through the
use of additional arguments.
Attributes can be set can be set using arguments of the form attribute = value
or
mapped using arguments of the form attribute = ~ expression
.
In formulas of the form A | B
, B
will be used to form facets using
facet_wrap()
or facet_grid()
.
This provides an alternative to
gf_facet_wrap()
and
gf_facet_grid()
that is terser and may feel more familiar to users
of lattice.
Evaluation of the ggplot2 code occurs in the environment of gformula
.
This will typically do the right thing when formulas are created on the fly, but might not
be the right thing if formulas created in one environment are used to create plots
in another.
data(penguins, package = "palmerpenguins")
gf_text(bill_length_mm ~ bill_depth_mm,
data = penguins,
label = ~species, color = ~species, size = 2, angle = 30
)
#> Warning: Removed 2 rows containing missing values (`geom_text()`).
penguins |>
gf_point(bill_length_mm ~ bill_depth_mm, color = ~species, alpha = 0.5) |>
gf_text(bill_length_mm ~ bill_depth_mm,
label = ~species, color = ~species,
size = 2, angle = 0, hjust = 0, nudge_x = 0.1, nudge_y = 0.1
)
#> Warning: Removed 2 rows containing missing values (`geom_point()`).
#> Warning: Removed 2 rows containing missing values (`geom_text()`).
if (require(dplyr)) {
data(penguins, package = "palmerpenguins")
penguins_means <-
penguins |>
group_by(species) |>
summarise(bill_length_mm = mean(bill_length_mm), bill_depth_mm = mean(bill_depth_mm))
gf_point(bill_length_mm ~ bill_depth_mm, data = penguins, color = ~species) |>
gf_label(bill_length_mm ~ bill_depth_mm,
data = penguins_means,
label = ~species, color = ~species, size = 2, alpha = 0.7
)
}
#> Warning: Removed 2 rows containing missing values (`geom_point()`).
#> Warning: Removed 2 rows containing missing values (`geom_label()`).