palettes

The goal of palettes is to provide methods for working with colour palettes for users and developers.

library(palettes)

Creating

pal_colour() is a nice way to create a colour vector. Colours can be a character vector of hexadecimal strings of the form "#RRGGBB" or "#RRGGBBAA", colour names from grDevices::colors(), or a positive integer that indexes into grDevices::palette(). By default, colour vectors are always printed as hex codes with colour previews.

colour_vector <- pal_colour(
  c("#a00e00", "#d04e00", "#f6c200", "#0086a8", "#132b69")
)

colour_vector
#> <palettes_colour[5]>
#> • #A00E00
#> • #D04E00
#> • #F6C200
#> • #0086A8
#> • #132B69

pal_palette() is a nice way to create named colour palettes.

colour_palette <- pal_palette(
  egypt = c("#dd5129", "#0f7ba2", "#43b284", "#fab255"),
  java  = c("#663171", "#cf3a36", "#ea7428", "#e2998a", "#0c7156")
)

colour_palette
#> <palettes_palette[2]>
#> $egypt
#> <palettes_colour[4]>
#> • #DD5129
#> • #0F7BA2
#> • #43B284
#> • #FAB255
#> 
#> $java
#> <palettes_colour[5]>
#> • #663171
#> • #CF3A36
#> • #EA7428
#> • #E2998A
#> • #0C7156

Casting and coercion

To compliment pal_colour(), palettes provides as_colour() to cast objects into colour vectors.

colour_strings <- c("orange", "purple")
as_colour(colour_strings)
#> <palettes_colour[2]>
#> • #FFA500
#> • #A020F0

To compliment pal_palette(), palettes provides as_palette() to cast objects into colour palettes.

colour_list <- list(OrPu = c("orange", "purple"))
as_palette(colour_list)
#> <palettes_palette[1]>
#> $OrPu
#> <palettes_colour[2]>
#> • #FFA500
#> • #A020F0

Colour vectors and colour palettes can also be coerced into a tibble with as_tibble(). See vignette("tibble", package = "tibble") for an overview of tibbles.

as_tibble(colour_vector)
#> # A tibble: 5 × 1
#>   colour   
#>   <colour> 
#> 1 • #A00E00
#> 2 • #D04E00
#> 3 • #F6C200
#> 4 • #0086A8
#> 5 • #132B69

as_tibble(colour_palette)
#> # A tibble: 9 × 2
#>   palette colour   
#>   <chr>   <colour> 
#> 1 egypt   • #DD5129
#> 2 egypt   • #0F7BA2
#> 3 egypt   • #43B284
#> 4 egypt   • #FAB255
#> 5 java    • #663171
#> 6 java    • #CF3A36
#> 7 java    • #EA7428
#> 8 java    • #E2998A
#> 9 java    • #0C7156

Subsetting

Colour vectors can be subset using [.

• To extract one or more colours use positive integers:

  colour_vector[3]
  #> <palettes_colour[1]>
  #> • #F6C200

• To drop one or more colours use negative integers:

  colour_vector[-3]
  #> <palettes_colour[4]>
  #> • #A00E00
  #> • #D04E00
  #> • #0086A8
  #> • #132B69

• To move one or more colours extract, drop, and combine:

  c(colour_vector[-3], colour_vector[3])
  #> <palettes_colour[5]>
  #> • #A00E00
  #> • #D04E00
  #> • #0086A8
  #> • #132B69
  #> • #F6C200

Colour palettes can be subset using [, [[, and $.

• To extract one or more colour palettes use [:

  colour_palette["egypt"]
  #> <palettes_palette[1]>
  #> $egypt
  #> <palettes_colour[4]>
  #> • #DD5129
  #> • #0F7BA2
  #> • #43B284
  #> • #FAB255

• To extract a single colour palette as a colour vector use [[ or $:

  colour_palette[["egypt"]]
  #> <palettes_colour[4]>
  #> • #DD5129
  #> • #0F7BA2
  #> • #43B284
  #> • #FAB255
  
  colour_palette$egypt
  #> <palettes_colour[4]>
  #> • #DD5129
  #> • #0F7BA2
  #> • #43B284
  #> • #FAB255

• To get names of colour palettes use names():

  names(colour_palette)
  #> [1] "egypt" "java"

Plotting

plot() is a nice way to showcase colour vectors and colour palettes. The appearance of the plot depends on the input.

• Colour vectors are plotted as swatches:

  plot(colour_vector)

  

• Single colour palettes are plotted as swatches with a palette name overlay:

  plot(colour_palette["egypt"])

  

• Multiple colour palettes are plotted as faceted swatches with palette name titles:

  plot(colour_palette)

  

To interpolate or change the direction of colours in a plot, use the optional n, direction, space, or interpolate arguments.

plot(colour_vector, n = 7, direction = -1, interpolate = "linear")

All plots are ggplot2 objects and can be customized using any of the standard ggplot2 methods. See the ggplot2 customizing FAQ for some common examples.

Printing

The printing behaviour of colour vectors can be adjusted using a variety of global options. See help("palettes-options") for a list of all the available options and their default values.

For example, to change the symbol used for colour previews, set the palettes.print_symbol option.

options(palettes.print_symbol = "square")
colour_vector
#> <palettes_colour[5]>
#> ■ #A00E00
#> ■ #D04E00
#> ■ #F6C200
#> ■ #0086A8
#> ■ #132B69

Set multiple options together for unique printing styles.

• Print colour vectors compactly:

  options(
    palettes.print_symbol = "circle_large",
    palettes.print_hex = FALSE,
    palettes.print_width = 5
  )
  colour_palette
  #> <palettes_palette[2]>
  #> $egypt
  #> <palettes_colour[4]>
  #> ⬤⬤⬤⬤
  #> 
  #> $java
  #> <palettes_colour[5]>
  #> ⬤⬤⬤⬤⬤

• Mimic the appearance of a character vector:

  options(
    palettes.print_symbol = FALSE,
    palettes.print_sep = ", ",
    palettes.print_width = 5,
    palettes.print_index = TRUE
  )
  colour_vector
  #> <palettes_colour[5]>
  #> [1] #A00E00, #D04E00, #F6C200, #0086A8, #132B69

Set any of these options in your .Rprofile dotfile to have them persist across R sessions on a global or per-project basis.