Paul Tol's PRGn Diverging Colour Scheme

## Usage

scale_colour_PRGn(
...,
reverse = FALSE,
range = c(0, 1),
midpoint = 0,
discrete = FALSE,
aesthetics = "colour"
)

scale_color_PRGn(
...,
reverse = FALSE,
range = c(0, 1),
midpoint = 0,
discrete = FALSE,
aesthetics = "colour"
)

scale_fill_PRGn(
...,
reverse = FALSE,
range = c(0, 1),
midpoint = 0,
discrete = FALSE,
aesthetics = "fill"
)

scale_edge_colour_PRGn(
...,
reverse = FALSE,
range = c(0, 1),
midpoint = 0,
discrete = FALSE,
aesthetics = "edge_colour"
)

scale_edge_color_PRGn(
...,
reverse = FALSE,
range = c(0, 1),
midpoint = 0,
discrete = FALSE,
aesthetics = "edge_colour"
)

scale_edge_fill_PRGn(
...,
reverse = FALSE,
range = c(0, 1),
midpoint = 0,
discrete = FALSE,
aesthetics = "edge_fill"
)

## Arguments

...

Arguments passed to ggplot2::continuous_scale().

reverse

A logical scalar. Should the resulting vector of colors be reversed?

range

A length-two numeric vector specifying the fraction of the scheme's colour domain to keep.

midpoint

A length-one numeric vector giving the midpoint (in data value) of the diverging scale. Defaults to 0.

discrete

A logical scalar: should the colour scheme be used as a discrete scale? If TRUE, it is a departure from Paul Tol's recommendations and likely a very poor use of colour.

aesthetics

A character string or vector of character strings listing the name(s) of the aesthetic(s) that this scale works with.

## Value

A continuous scale.

## Interpolation

If more colors than defined are needed from a given scheme, the colour coordinates are linearly interpolated to provide a continuous version of the scheme.

Note that the default colour for NA can be overridden by passing a value to ggplot2::continuous_scale().

## References

Tol, P. (2018). Colour Schemes. SRON. Technical Note No. SRON/EPS/TN/09-002, issue 3.1. URL: https://personal.sron.nl/~pault/data/colourschemes.pdf

Other diverging colour schemes: scale_crameri_bam, scale_crameri_berlin, scale_crameri_broc, scale_crameri_cork, scale_crameri_lisbon, scale_crameri_roma, scale_crameri_tofino, scale_crameri_vanimo, scale_crameri_vik, scale_tol_BuRd, scale_tol_sunset

Other Paul Tol's colour schemes: scale_tol_BuRd, scale_tol_YlOrBr, scale_tol_bright, scale_tol_dark, scale_tol_discreterainbow, scale_tol_highcontrast, scale_tol_iridescent, scale_tol_light, scale_tol_mediumcontrast, scale_tol_muted, scale_tol_pale, scale_tol_smoothrainbow, scale_tol_sunset, scale_tol_vibrant

N. Frerebeau

## Examples

data(economics, package = "ggplot2")

ggplot2::ggplot(economics, ggplot2::aes(psavert, pce, colour = unemploy)) +
ggplot2::geom_point() +
scale_color_sunset(reverse = TRUE, midpoint = 12000)

ggplot2::ggplot(economics, ggplot2::aes(psavert, pce, colour = unemploy)) +
ggplot2::geom_point() +
scale_color_BuRd(midpoint = 9000)

ggplot2::ggplot(economics, ggplot2::aes(psavert, pce, colour = unemploy)) +
ggplot2::geom_point() +
scale_color_PRGn(midpoint = 9000, range = c(0.25, 1))