scale_shape()
maps discrete variables to six easily discernible shapes.
If you have more than six levels, you will get a warning message, and the
seventh and subsequent levels will not appear on the plot. Use
scale_shape_manual()
to supply your own values. You can not map
a continuous variable to shape unless scale_shape_binned()
is used. Still,
as shape has no inherent order, this use is not advised.
scale_shape(..., solid = TRUE)
scale_shape_binned(..., solid = TRUE)
Arguments passed on to discrete_scale
palette
A palette function that when called with a single integer
argument (the number of levels in the scale) returns the values that
they should take (e.g., scales::hue_pal()
).
breaks
One of:
limits
One of:
NULL
to use the default scale values
A character vector that defines possible values of the scale and their order
A function that accepts the existing (automatic) values and returns new ones. Also accepts rlang lambda function notation.
drop
Should unused factor levels be omitted from the scale?
The default, TRUE
, uses the levels that appear in the data;
FALSE
uses all the levels in the factor.
na.translate
Unlike continuous scales, discrete scales can easily show
missing values, and do so by default. If you want to remove missing values
from a discrete scale, specify na.translate = FALSE
.
na.value
If na.translate = TRUE
, what aesthetic value should the
missing values be displayed as? Does not apply to position scales
where NA
is always placed at the far right.
aesthetics
The names of the aesthetics that this scale works with.
scale_name
The name of the scale that should be used for error messages associated with this scale.
name
The name of the scale. Used as the axis or legend title. If
waiver()
, the default, the name of the scale is taken from the first
mapping used for that aesthetic. If NULL
, the legend title will be
omitted.
labels
One of:
guide
A function used to create a guide or its name. See
guides()
for more information.
super
The super class to use for the constructed scale
Should the shapes be solid, TRUE
, or hollow,
FALSE
?
dsmall <- diamonds[sample(nrow(diamonds), 100), ]
(d <- ggplot(dsmall, aes(carat, price)) + geom_point(aes(shape = cut)))
#> Warning: Using shapes for an ordinal variable is not advised
d + scale_shape(solid = TRUE) # the default
d + scale_shape(solid = FALSE)
d + scale_shape(name = "Cut of diamond")
# To change order of levels, change order of
# underlying factor
levels(dsmall$cut) <- c("Fair", "Good", "Very Good", "Premium", "Ideal")
# Need to recreate plot to pick up new data
ggplot(dsmall, aes(price, carat)) + geom_point(aes(shape = cut))
#> Warning: Using shapes for an ordinal variable is not advised
# Show a list of available shapes
df_shapes <- data.frame(shape = 0:24)
ggplot(df_shapes, aes(0, 0, shape = shape)) +
geom_point(aes(shape = shape), size = 5, fill = 'red') +
scale_shape_identity() +
facet_wrap(~shape) +
theme_void()