Builds the discrete scales that carry a grouping variable: a
colour-vision-safe hue from cr_palette() plus a matching symbol from
cr_shapes(). Add the result to a plot with +, exactly like a single
scale.
Usage
cr_scale_group(
aesthetics = c("colour", "fill", "shape"),
name = NULL,
guide_for = NULL,
drop = TRUE
)Arguments
- aesthetics
Character vector of aesthetics to scale. Any of
"colour","color","fill","shape".- name
Legend title.
NULL(default) keeps the mapped variable name.- guide_for
Aesthetics that keep a visible guide. Use
"all"when the aesthetics are drawn by the same layer and should merge into one key,"none"to suppress every guide. Defaults to the last ofaesthetics, which is the one drawn on top.- drop
Passed to the underlying scales: drop unused factor levels (default
TRUE).
Details
Because the same variable is mapped to several aesthetics, the guide is
emitted for one aesthetic only. A duplicate guide is what makes a composed
figure print the same legend twice, so guide_for names the single
aesthetic that keeps its legend and every other aesthetic is suppressed.
See also
cr_palette(), cr_shapes(), cr_theme()
Other plot design:
cr_palette(),
cr_shapes(),
cr_theme()
Examples
df <- data.frame(g = rep(c("a", "b", "c"), each = 10), y = rnorm(30))
ggplot2::ggplot(df, ggplot2::aes(g, y, colour = g, shape = g)) +
ggplot2::geom_point() +
cr_scale_group(c("colour", "shape"), name = "group") +
cr_theme()
