Get or set global options for c4a. Works similar as the base function options
Details
| Option | Description |
| defaults | Default palettes per type |
| CBF_th | Parameters that label a palette as color blind friendly |
| CBVF_th | Parameters that label a palette as very color blind friendly |
| CBU_th | Parameters that label a palette as color blind unfriendly |
| CrangeFair | Maximum chroma range for which a palette is considered harmonic |
| CrangeUnfair | Minimum chroma range for which a palette is considered disharmonic |
| LrangeFair | Maximum luminance range for which a palette is considered harmonic |
| LrangeUnfair | Minimum luminance range for which a palette is considered disharmonic |
| Cintense | Chroma of colors that are considered intense |
| Cpastel | Chroma of colors that are considered 'pastel' |
| HwidthDivRainbow | A diverging palette is labeled as 'rainbow hue' if HwidthL or HwidthR are at least HwidthDivRainbow |
| HwidthDivSingle | A diverging palette is labeled as 'single hue' if HwidthL and HwidthR are at most HwidthDivSingle |
| HwidthSeqRainbow | A sequential palette is labeled as 'rainbow hue' if Hwidth is at least HwidthSeqRainbow |
| HwidthSeqSingle | A sequential palette is labeled as 'single hue' if Hwidth is at most HwidthSeqSingle |
| naming_fun | Function that returns a distance matrix with the naming_colors (see examples) |
| naming_fun_args | List of arguments for naming_fun |
| naming_colors | Vector of prototype colors for the color names (see examples) |
| naming_softmax | List of parameters for the softmax function applied to the distance matrix |
Examples
# Example how to lower the color-blind friendly threshold
# for categorical palettes (so more smileys in the GUI!)
# CBF_th: one smiley
# CBVF_th: two smileys
# current table
if (FALSE) { # \dontrun{
c4a_table(n = 9, sort = "cbfriendly")
opts = c4a_options("CBF_th", "CBVF_th")
opts$CBF_th$cat["min_dist"] = 7
opts$CBVF_th$cat["min_dist"] = 10
old = c4a_options(opts)
# more smileys :-) :-)
c4a_table(n = 9, sort = "cbfriendly")
# set the old settings back
c4a_options(old)
} # }
# Example how to use own nameability function
#
# This function should:
# - have an argument "pal" (vector of colors)
# - optionally have other arguments
# - return a distance matrix of n rows (length of pal) and k columns (classes).
# It shoud have columns names that correspond to the naming colors (see below).
naming_RGB = function(pal) {
cols = colorspace::hex2RGB(pal)
coords = cols@coords
cls = apply(coords, MARGIN = 1, which.max)
mx = apply(coords, MARGIN = 1, max)
dominance = ((mx + 0.001) / (rowSums(coords) + 0.001))
cls[dominance < 0.4] = 4L
m = matrix(0, nrow = length(pal), ncol = 4,
dimnames = list(NULL, c("Red", "Green", "Blue", "Other")))
for (i in 1:nrow(m)) {
m[i, cls[i]] = 1
}
-m
}
# testing this function...
naming_RGB(c4a("brewer.set1")) #fair enough
#> Red Green Blue Other
#> [1,] -1 0 0 0
#> [2,] 0 0 -1 0
#> [3,] 0 -1 0 0
#> [4,] 0 0 -1 0
#> [5,] -1 0 0 0
#> [6,] -1 0 0 0
#> [7,] -1 0 0 0
#> [8,] -1 0 0 0
#> [9,] 0 0 0 -1
# This vector should contain the 'prototype' colors, and have names that correspond
# to the column names of the returned matrices by the function above.
names_RGB =
c("Red" = "#FF0000",
"Green" = "#00FF00",
"Blue" = "#0000FF",
"Other" = "#AAAAAA")
# Set the options (may take a while because if calculated the nameability scores)
if (FALSE) { # \dontrun{
c4a_options(naming_fun = naming_RGB,
naming_fun_args = list(),
naming_colors = names_RGB)
} # }