Colors for a figure's levels, by role

The house color rule for EDA and follow-up figures, as a named vector you can check or reuse: an event is vermillion, censored is blue, missing is light gray, and every other level takes a colorblind-safe color in order. To apply the rule to a plot, use scale_fill_hv() or scale_color_hv(), which call this for each panel.

Usage

hv_role_palette(levels, event = NULL, censored = NULL, missing = "(Missing)")

Arguments

levels

Character vector of distinct level names, in drawing order.

event, censored

Level names that take the event or the censored color, or NULL for none. Names not in levels are ignored.

missing

Level name that stands for missing values. "(Missing)" is the explicit level hv_eda() adds.

Value

A character vector of hex colors, named by levels and in the same order.

Details

Every color is decided from levels alone:

1. A level named in event is #D55E00, in censored #0072B2, and in missing #CCCCCC. These hold even when the level is the only one.

2. Every other level, in levels order, takes the light series of hv_ppt_palette(): the Okabe-Ito colors without yellow and sky blue, starting at blue, so a sole level with no role is blue.

3. When any of levels is named in event or censored, blue and vermillion leave that series, so no other level can be mistaken for the event or for censored. A role name absent from levels changes nothing, so one call can serve panels that do and do not carry the event.

4. When the other levels outnumber the series, all of them switch to Paul Tol's muted palette, without its sand and cyan, and without its rose when a role is present. Beyond that there are no more colorblind-safe colors, and the function stops with an error of class hv_role_palette_capacity.

Every color except the missing gray is at least 2:1 against white. The gray is fainter on purpose: missing is the one level meant to recede.

See also

scale_fill_hv() and scale_color_hv() to apply the rule to a plot; hv_ppt_palette() for series colors with no role attached.

Examples

hv_role_palette(c("No event", "Reoperation", "Death"),
                event = "Death", censored = "No event")
#>    No event Reoperation       Death 
#>   "#0072B2"   "#009E73"   "#D55E00" 
hv_role_palette(c("Female", "Male", "(Missing)"))
#>    Female      Male (Missing) 
#> "#0072B2" "#D55E00" "#CCCCCC"