Visualizing CMAP color palettes — viz

The cmapplot package contains a many color palettes extracted from the larger, official CMAP color palette. Helper functions allow the user to inspect the various palettes before applying them to plots.

viz_gradient(pal, ttl = NULL)

viz_palette(pal, ttl = NULL, num = NULL)

fetch_pal(
  pal,
  which = c("discrete", "sequential", "divergent"),
  return = c("colors", "type", "exists")
)

Arguments

pal: character, name of a a cmapplot palette, or a vector of colors representing a palette
ttl: character, title to be displayed (the name of the palette)
num: numeric, the number of colors to display
which: a vector of palette types to consider
return: Value to return. "colors", the default, returns the palette as a vector of colors. "type" returns the palette's type. "Exists" returns TRUE or FALSE based on whether the name is found in the palettes table.

Details

Palettes are stored in a tibble the cmapplot_globals environment. The user can access this tibble with get_cmapplot_global, but it is easier to access information about a single palette with fetch_pal.

viz_palette and viz_gradient draw the palette to the plots window. These functions are modified with respect from the ochRe package.

For more information about available cmapplot color palettes and how to apply them, see vignette("colors").

Functions

viz_gradient(): Interpolates the range of colors a sequential or divergent palette offers when used on a continuous scale.
viz_palette(): Displays the colors of any cmapplot palette
fetch_pal(): Returns details about a palette

Examples

# Vizualize a sequential or divergent palette with interpolation
viz_gradient("green_teal_blue")


# Visualize a single palette as individual colors
viz_palette("legislation")


# Print names and types of all available palettes
as.data.frame(get_cmapplot_global("palettes")[1:2])
#>                 name       type
#> 1         prosperity   discrete
#> 2          community   discrete
#> 3        environment   discrete
#> 4         governance   discrete
#> 5           mobility   discrete
#> 6        legislation   discrete
#> 7             friday   discrete
#> 8               race   discrete
#> 9               reds sequential
#> 10           oranges sequential
#> 11           yellows sequential
#> 12            greens sequential
#> 13             teals sequential
#> 14             blues sequential
#> 15           purples sequential
#> 16             grays sequential
#> 17 yellow_orange_red sequential
#> 18   green_teal_blue sequential
#> 19        orange_red sequential
#> 20     yellow_orange sequential
#> 21      yellow_green sequential
#> 22        green_teal sequential
#> 23         teal_blue sequential
#> 24        red_purple sequential
#> 25     yellow_purple  divergent
#> 26       orange_blue  divergent
#> 27          red_teal  divergent
#> 28      purple_green  divergent
#> 29       blue_yellow  divergent
#> 30       teal_orange  divergent
#> 31         green_red  divergent

# Identify the first two colors of the Prosperity Palette
fetch_pal("prosperity")[1:2]
#> [1] "#662f00" "#e5d072"

# Confirm that "reds" is a sequential palette
fetch_pal("reds", which = "sequential", return = "exists")
#> [1] TRUE