scale_*_gradient creates a two colour gradient (low-high),
scale_*_gradient2 creates a diverging colour gradient (low-mid-high),
scale_*_gradientn creates a n-colour gradient. For binned variants of
these scales, see the color steps scales.
scale_colour_gradient( ..., low = "#132B43", high = "#56B1F7", space = "Lab", na.value = "grey50", guide = "colourbar", aesthetics = "colour" ) scale_fill_gradient( ..., low = "#132B43", high = "#56B1F7", space = "Lab", na.value = "grey50", guide = "colourbar", aesthetics = "fill" ) scale_colour_gradient2( ..., low = muted("red"), mid = "white", high = muted("blue"), midpoint = 0, space = "Lab", na.value = "grey50", guide = "colourbar", aesthetics = "colour" ) scale_fill_gradient2( ..., low = muted("red"), mid = "white", high = muted("blue"), midpoint = 0, space = "Lab", na.value = "grey50", guide = "colourbar", aesthetics = "fill" ) scale_colour_gradientn( ..., colours, values = NULL, space = "Lab", na.value = "grey50", guide = "colourbar", aesthetics = "colour", colors ) scale_fill_gradientn( ..., colours, values = NULL, space = "Lab", na.value = "grey50", guide = "colourbar", aesthetics = "fill", colors )
Arguments
| ... | Arguments passed on to
|
|---|---|
| low, high | Colours for low and high ends of the gradient. |
| space | colour space in which to calculate gradient. Must be "Lab" - other values are deprecated. |
| na.value | Colour to use for missing values |
| guide | Type of legend. Use |
| aesthetics | Character string or vector of character strings listing the
name(s) of the aesthetic(s) that this scale works with. This can be useful, for
example, to apply colour settings to the |
| mid | colour for mid point |
| midpoint | The midpoint (in data value) of the diverging scale. Defaults to 0. |
| colours, colors | Vector of colours to use for n-colour gradient. |
| values | if colours should not be evenly positioned along the gradient
this vector gives the position (between 0 and 1) for each colour in the
|
Details
Default colours are generated with munsell and
mnsl(c("2.5PB 2/4", "2.5PB 7/10")). Generally, for continuous
colour scales you want to keep hue constant, but vary chroma and
luminance. The munsell package makes this easy to do using the
Munsell colour system.
See also
scales::seq_gradient_pal() for details on underlying
palette, scale_colour_steps() for binned variants of these scales.
Other colour scales:
scale_alpha(),
scale_colour_brewer(),
scale_colour_continuous(),
scale_colour_grey(),
scale_colour_hue(),
scale_colour_steps(),
scale_colour_viridis_d()
Examples
df <- data.frame( x = runif(100), y = runif(100), z1 = rnorm(100), z2 = abs(rnorm(100)) ) df_na <- data.frame( value = seq(1, 20), x = runif(20), y = runif(20), z1 = c(rep(NA, 10), rnorm(10)) ) # Default colour scale colours from light blue to dark blue ggplot(df, aes(x, y)) + geom_point(aes(colour = z2))# For diverging colour scales use gradient2 ggplot(df, aes(x, y)) + geom_point(aes(colour = z1)) + scale_colour_gradient2()# Use your own colour scale with gradientn ggplot(df, aes(x, y)) + geom_point(aes(colour = z1)) + scale_colour_gradientn(colours = terrain.colors(10))# Equivalent fill scales do the same job for the fill aesthetic ggplot(faithfuld, aes(waiting, eruptions)) + geom_raster(aes(fill = density)) + scale_fill_gradientn(colours = terrain.colors(10))# Adjust colour choices with low and high ggplot(df, aes(x, y)) + geom_point(aes(colour = z2)) + scale_colour_gradient(low = "white", high = "black")# Avoid red-green colour contrasts because ~10% of men have difficulty # seeing them # Use `na.value = NA` to hide missing values but keep the original axis range ggplot(df_na, aes(x = value, y)) + geom_bar(aes(fill = z1), stat = "identity") + scale_fill_gradient(low = "yellow", high = "red", na.value = NA)ggplot(df_na, aes(x, y)) + geom_point(aes(colour = z1)) + scale_colour_gradient(low = "yellow", high = "red", na.value = NA)#> Warning: Removed 10 rows containing missing values (geom_point).
