HCL-Based Continuous Qualitative Color Scales for ggplot2 — scale_colour_continuous

Continuous ggplot2 color scales using the color palettes generated by qualitative_hcl. These scales are provided for completeness. It is not normally a good idea to color a continuous variable using a qualitative scale.

scale_colour_continuous_qualitative(
  palette = NULL,
  c1 = NULL,
  l1 = NULL,
  h1 = NULL,
  h2 = NULL,
  alpha = 1,
  rev = FALSE,
  begin = 0,
  end = 1,
  na.value = "grey50",
  guide = "colourbar",
  aesthetics = "colour",
  n_interp = 11,
  ...
)

scale_color_continuous_qualitative(
  palette = NULL,
  c1 = NULL,
  l1 = NULL,
  h1 = NULL,
  h2 = NULL,
  alpha = 1,
  rev = FALSE,
  begin = 0,
  end = 1,
  na.value = "grey50",
  guide = "colourbar",
  aesthetics = "colour",
  n_interp = 11,
  ...
)

scale_fill_continuous_qualitative(..., aesthetics = "fill")

Arguments

palette: The name of the palette to be used. Run hcl_palettes(type = "qualitative") for available options.
c1: Chroma value, used for all colors in the scale.
l1: Luminance value, used for all colors in the scale.
h1: Beginning hue value.
h2: Ending hue value.
alpha: Numeric vector of values in the range [0, 1] for alpha transparency channel (0 means transparent and 1 means opaque).
rev: If TRUE, reverses the order of the colors in the color scale.
begin: Number in the range of [0, 1] indicating to which point in the color scale the smallest data value should be mapped.
end: Number in the range of [0, 1] indicating to which point in the color scale the largest data value should be mapped.
na.value: Color to be used for missing data points.
guide: Type of legend. Use "colourbar" for continuous color bar.
aesthetics: The ggplot2 aesthetics to which this scale should be applied.
n_interp: Number of discrete colors that should be used to interpolate the continuous color scale. 11 will work fine in most cases.
...: common continuous scale parameters: `name`, `breaks`, `labels`, and `limits`. See continuous_scale for more details.

Details

If both a valid palette name and palette parameters are provided then the provided palette parameters overwrite the parameters in the named palette. This enables easy customization of named palettes.

Examples

library("ggplot2")

# none of these examples are necessarily good ideas
gg <- ggplot(iris, aes(x = Species, y = Sepal.Width, color = Sepal.Length)) + 
  geom_jitter(width = 0.3) + theme_minimal()
  
gg + scale_color_continuous_qualitative(palette = "Warm")

gg + scale_color_continuous_qualitative(palette = "Cold", l1 = 60)

gg + scale_color_continuous_qualitative(palette = "Harmonic", rev = TRUE)


nx = 87
ny = 61
df <- data.frame(height = c(volcano), x = rep(1:nx, ny), y = rep(1:ny, each = nx))
ggplot(df, aes(x, y, fill=height)) + 
  geom_raster() + scale_fill_continuous_qualitative(palette = "Dark 3") +
  coord_fixed(expand = FALSE)