geom_text()
adds text directly to the plot. geom_label()
draws
a rectangle behind the text, making it easier to read.
geom_label( mapping = NULL, data = NULL, stat = "identity", position = "identity", ..., parse = FALSE, nudge_x = 0, nudge_y = 0, label.padding = unit(0.25, "lines"), label.r = unit(0.15, "lines"), label.size = 0.25, na.rm = FALSE, show.legend = NA, inherit.aes = TRUE ) geom_text( mapping = NULL, data = NULL, stat = "identity", position = "identity", ..., parse = FALSE, nudge_x = 0, nudge_y = 0, check_overlap = FALSE, na.rm = FALSE, show.legend = NA, inherit.aes = TRUE )
mapping | Set of aesthetic mappings created by |
---|---|
data | The data to be displayed in this layer. There are three options: If A A |
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. |
... | Other arguments passed on to |
parse | If |
nudge_x, nudge_y | Horizontal and vertical adjustment to nudge labels by. Useful for offsetting text from points, particularly on discrete scales. |
label.padding | Amount of padding around label. Defaults to 0.25 lines. |
label.r | Radius of rounded corners. Defaults to 0.15 lines. |
label.size | Size of label border, in mm. |
na.rm | If |
show.legend | logical. Should this layer be included in the legends?
|
inherit.aes | If |
check_overlap | If |
Note that the "width" and "height" of a text element are 0, so stacking and dodging text will not work by default, and axis limits are not automatically expanded to include all text. Obviously, labels do have height and width, but they are physical units, not data units. The amount of space they occupy on the plot is not constant in data units: when you resize a plot, labels stay the same size, but the size of the axes changes.
geom_text()
and geom_label()
add labels for each row in the
data, even if coordinates x, y are set to single values in the call
to geom_label()
or geom_text()
.
To add labels at specified points use annotate()
with
annotate(geom = "text", ...)
or annotate(geom = "label", ...)
.
geom_text()
understands the following aesthetics (required aesthetics are in bold):
x
y
label
alpha
angle
colour
family
fontface
group
hjust
lineheight
size
vjust
Learn more about setting these aesthetics in vignette("ggplot2-specs")
.
geom_label()
Currently geom_label()
does not support the angle
aesthetic and
is considerably slower than geom_text()
. The fill
aesthetic
controls the background colour of the label.
You can modify text alignment with the vjust
and hjust
aesthetics. These can either be a number between 0 (right/bottom) and
1 (top/left) or a character ("left"
, "middle"
, "right"
, "bottom"
,
"center"
, "top"
). There are two special alignments: "inward"
and
"outward"
. Inward always aligns text towards the center, and outward
aligns it away from the center.
# Avoid overlaps p + geom_text(check_overlap = TRUE)# Labels with background p + geom_label()# Change size of the label p + geom_text(size = 10)if (FALSE) { # Doesn't work on all systems p + geom_text(family = "Times New Roman") } # Add aesthetic mappings p + geom_text(aes(colour = factor(cyl)))# Scale height of text, rather than sqrt(height) p + geom_text(aes(size = wt)) + scale_radius(range = c(3,6))# You can display expressions by setting parse = TRUE. The # details of the display are described in ?plotmath, but note that # geom_text uses strings, not expressions. p + geom_text(aes(label = paste(wt, "^(", cyl, ")", sep = "")), parse = TRUE)# Add a text annotation p + geom_text() + annotate("text", label = "plot mpg vs. wt", x = 2, y = 15, size = 8, colour = "red")# \donttest{ # Aligning labels and bars -------------------------------------------------- df <- data.frame( x = factor(c(1, 1, 2, 2)), y = c(1, 3, 2, 1), grp = c("a", "b", "a", "b") ) # ggplot2 doesn't know you want to give the labels the same virtual width # as the bars: ggplot(data = df, aes(x, y, group = grp)) + geom_col(aes(fill = grp), position = "dodge") + geom_text(aes(label = y), position = "dodge")#> Warning: Width not defined. Set with `position_dodge(width = ?)`# So tell it: ggplot(data = df, aes(x, y, group = grp)) + geom_col(aes(fill = grp), position = "dodge") + geom_text(aes(label = y), position = position_dodge(0.9))# Use you can't nudge and dodge text, so instead adjust the y position ggplot(data = df, aes(x, y, group = grp)) + geom_col(aes(fill = grp), position = "dodge") + geom_text( aes(label = y, y = y + 0.05), position = position_dodge(0.9), vjust = 0 )# To place text in the middle of each bar in a stacked barplot, you # need to set the vjust parameter of position_stack() ggplot(data = df, aes(x, y, group = grp)) + geom_col(aes(fill = grp)) + geom_text(aes(label = y), position = position_stack(vjust = 0.5))# Justification ------------------------------------------------------------- df <- data.frame( x = c(1, 1, 2, 2, 1.5), y = c(1, 2, 1, 2, 1.5), text = c("bottom-left", "bottom-right", "top-left", "top-right", "center") ) ggplot(df, aes(x, y)) + geom_text(aes(label = text))# }