scale-colour-discrete

Discrete colour scale mapping categorical levels to stroke colours.

Usage

scale-colour-discrete(
  ..args,
)

Parameters

Parameter	Default	Description
..args

Returns

Scale object consumed by plot.

Examples

Default palette mapping three categories to the library’s eight reserved discrete colours.

#let d = (
  (x: 1, y: 2, sp: "a"),
  (x: 2, y: 4, sp: "b"),
  (x: 3, y: 3, sp: "c"),
)
#plot(
  data: d,
  mapping: aes(x: "x", y: "y", colour: "sp"),
  layers: (geom-point(size: 3pt),),
  scales: (scale-colour-discrete(),),
  width: 10cm,
  height: 6cm,
)

Override palette with an explicit colour array to hand-pick the mapping order.

#let d = (
  (x: 1, y: 2, sp: "a"),
  (x: 2, y: 4, sp: "b"),
  (x: 3, y: 3, sp: "c"),
)
#plot(
  data: d,
  mapping: aes(x: "x", y: "y", colour: "sp"),
  layers: (geom-point(size: 3pt),),
  scales: (scale-colour-discrete(palette: (
    rgb("#1b9e77"), rgb("#d95f02"), rgb("#7570b3"),
  )),),
  width: 10cm,
  height: 6cm,
)

Bind a colour-blind-friendly palette to penguin species and reorder the legend via limits.

#plot(
  data: penguins,
  mapping: aes(x: "flipper-len", y: "body-mass", colour: "species"),
  layers: (geom-point(size: 2pt, alpha: 0.85),),
  scales: (scale-colour-discrete(
    palette: (rgb("#0072B2"), rgb("#D55E00"), rgb("#009E73")),
    limits: ("Adelie", "Chinstrap", "Gentoo"),
  ),),
  labs: labs(x: "Flipper Length (mm)", y: "Body Mass (g)", colour: "Species"),
  width: 11cm,
  height: 6cm,
)

See also

scale-colour-manual, scale-colour-viridis-d, scale-fill-discrete.