HCL-Based Continuous Flexible Diverging Scales for ggplot2

Continuous ggplot2 color scales using the color palettes generated by divergingx_hcl.

scale_colour_continuous_divergingx(
  palette = "Geyser",
  c1 = NULL,
  c2 = NULL,
  c3 = NULL,
  l1 = NULL,
  l2 = NULL,
  l3 = NULL,
  h1 = NULL,
  h2 = NULL,
  h3 = NULL,
  p1 = NULL,
  p2 = NULL,
  p3 = NULL,
  p4 = NULL,
  cmax1 = NULL,
  cmax2 = NULL,
  alpha = 1,
  rev = FALSE,
  mid = 0,
  na.value = "grey50",
  guide = "colourbar",
  n_interp = 11,
  aesthetics = "colour",
  ...
)

scale_color_continuous_divergingx(
  palette = "Geyser",
  c1 = NULL,
  c2 = NULL,
  c3 = NULL,
  l1 = NULL,
  l2 = NULL,
  l3 = NULL,
  h1 = NULL,
  h2 = NULL,
  h3 = NULL,
  p1 = NULL,
  p2 = NULL,
  p3 = NULL,
  p4 = NULL,
  cmax1 = NULL,
  cmax2 = NULL,
  alpha = 1,
  rev = FALSE,
  mid = 0,
  na.value = "grey50",
  guide = "colourbar",
  n_interp = 11,
  aesthetics = "colour",
  ...
)

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

Arguments

palette	The name of the palette to be used.
h1, h2, h3, c1, c2, c3, l1, l2, l3, p1, p2, p3, p4, cmax1, cmax2	Parameters to customize the scale. See divergingx_hcl for details.
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.
mid	Data value that should be mapped to the mid-point of the diverging color scale.
na.value	Color to be used for missing data points.
guide	Type of legend. Use "colourbar" for continuous color bar.
n_interp	Number of discrete colors that should be used to interpolate the continuous color scale. For diverging scales, it is important to use an odd number to capture the color at the midpoint.
aesthetics	The ggplot2 aesthetics to which this scale should be applied.
...	common continuous scale parameters: `name`, `breaks`, `labels`, and `limits`. See continuous_scale for more details.

Details

Available CARTO palettes: ArmyRose, Earth, Fall, Geyser, TealRose, Temps, Tropic.

Available ColorBrewer.org palettes: Spectral, PuOr, RdYlGn, RdYlBu, RdGy, BrBG, PiYG, PRGn, RdBu.

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")

# volcano plot (difference from mean height)
nx = 87
ny = 61
df <- data.frame(diff = c(volcano) - mean(volcano), x = rep(1:nx, ny), y = rep(1:ny, each = nx))
ggplot(df, aes(x, y, fill=diff)) + 
  geom_raster() + scale_fill_continuous_divergingx(palette = "Fall", rev = TRUE) +
  coord_fixed(expand = FALSE)


# adapted from stackoverflow: https://stackoverflow.com/a/20127706/4975218

# generate dataset and base plot
set.seed(100)
df <- data.frame(country = LETTERS, V = runif(26, -40, 40))
df$country = factor(LETTERS, LETTERS[order(df$V)]) # reorder factors
gg <- ggplot(df, aes(x = country, y = V, fill = V)) +
  geom_bar(stat = "identity") +
  labs(y = "Under/over valuation in %", x = "Country") +
  coord_flip() + theme_minimal()
  
# plot with diverging scale "Geyser"
gg + scale_fill_continuous_divergingx(palette = "Geyser")

# plot with diverging scale "ArmyRose"
gg + scale_fill_continuous_divergingx(palette = "ArmyRose")