Package 'hueR'

Make HCL palette for groups with multiple levels

Description

Makes a palette for dataframe where levels within groups defined by the group variable share the same hue but different shades, levels within group based on the shade variable.

Usage

hueGroupPal(
  df,
  group,
  shade,
  maxShades = 5,
  hues = hueSet(),
  huePalFun = huePal(),
  manual = c(Other = "lightgrey")
)

Arguments

df	dataframe with at least two variables (treated as categories)
group	variable name used to assign hues
shade	variable name used to assign colour shades of same hue
maxShades	maximum allowed number of shades per hue
hues	hues available to use for unique levels of group variable
huePalFun	function used to create single hue palette for levels of shade variable
manual	NULL or manual additions or replacements for returned palette in the style of c(name = value, ....)

Value

named character vector of colours

Examples

library(dplyr)
library(ggplot2)

# sort countries, within continents, by average population
sortedSummary <- gapminder::gapminder %>%
  group_by(continent, country) %>%
  summarise(AvPop = mean(pop, na.rm = TRUE), .groups = "keep") %>%
  group_by(continent) %>%
  arrange(.by_group = TRUE, desc(AvPop))

# create palettes
countryPal6 <- sortedSummary %>%
  hueGroupPal(group = "continent", shade = "country", maxShades = 6)


# plot population per year
gapminder::gapminder %>%
  group_by(year) %>%
  ggplot(aes(
    x = factor(year), y = pop,
    # setting as factor with levels in correct order ensures ordering of bars
    fill = factor(country, levels = names(countryPal6))
  )) +
  geom_col() +
  guides(fill = "none") +
  # setting manual scale of course sets correct colours
  scale_fill_manual(values = countryPal6) +
  ggfittext::geom_fit_text(
    aes(ymin = 0, ymax = pop, label = country),
    position = "stack", colour = "white"
  ) +
  theme_classic() +
  coord_cartesian(expand = FALSE)


# plot population per year as share of world total that year
gapminder::gapminder %>%
  group_by(year) %>%
  mutate(popPerc = pop/sum(pop, na.rm = TRUE)) %>%
  ggplot(aes(
    x = factor(year), y = popPerc,
    # setting as factor with levels in correct order ensures ordering of bars
    fill = factor(country, levels = names(countryPal6))
  )) +
  geom_col() +
  guides(fill = "none") +
  # setting manual scale of course sets correct colours
  scale_fill_manual(values = countryPal6) +
  ggfittext::geom_fit_text(
    aes(ymin = 0, ymax = popPerc, label = country),
    position = "stack", colour = "white"
  ) +
  theme_classic() +
  coord_cartesian(expand = FALSE)


# plot with modified palette
countryPal6alt <- sortedSummary %>%
  hueGroupPal(group = "continent", shade = "country", maxShades = 6,
              hues = hueSet(start = 0))

gapminder::gapminder %>%
  group_by(year) %>%
  mutate(popPerc = pop/sum(pop, na.rm = TRUE)) %>%
  # dplyr::filter(year > 1970) %>%
  ggplot(aes(
    x = factor(year), y = popPerc,
    # setting as factor with levels in correct order ensures ordering of bars
    fill = factor(country, levels = names(countryPal6alt))
  )) +
  geom_col() +
  guides(fill = "none") +
  # setting manual scale of course sets correct colours
  scale_fill_manual(values = countryPal6alt) +
  ggfittext::geom_fit_text(grow = TRUE,
                           aes(ymin = 0, ymax = popPerc, label = country),
                           position = "stack", colour = "white"
  ) +
  theme_classic() +
  coord_cartesian(expand = FALSE)

---

Create (named) single-hue gradient palette

Description

Function to create create HCL palette of n colours based on fixed hue. Luminance monotonically increases, whilst chroma increases and then decreases.

If names provided: return named palette of same length as unique(names), with n distinct colours (if n is left null, all colours are unique)

If the hue value is left as NULL, a function will be returned, which can generate a palette when given a hue values and n and/or names

Usage

huePal(
  hue = NULL,
  names = NULL,
  n = NULL,
  minChroma = 40,
  maxChroma = 150,
  minLum = 10,
  maxLum = 98,
  power = 0.8
)

Arguments

hue	numeric hue value, or NULL to return palette function
names	names for palette, or NULL for unnamed palette of length n
n	number of unique shades in palette
minChroma	minimum Chroma for palette
maxChroma	maximum Chroma for palette
minLum	minimum luminance for palette
maxLum	maximum luminance for palette
power	power used by colorspace::sequential_hcl()

Details

Uses colorspace::sequential_hcl() with a fixed hue to generate palettes.

The palette generated will be roughly centered around the midpoint of the luminance range, and at approximately the maximum chroma.

Note that edges of generated palette are cut off so min and max luminances are never returned. This is because they are, by default, too dark/light to be distinguishable across hues.

Value

vector of colours, possibly named, or a function

Examples

pal <- huePal(hue = 120, n = 9)
scales::show_col(pal, borders = NA)
huePal(hue = 120, names = letters[1:9]) == huePal(hue = 120, n = 9)

# more names than shades --> repeats last shade
extendedPal <- huePal(hue = 120, names = letters[1:16], n = 9)
scales::show_col(extendedPal, borders = NA)

---

Get a set of equally spaced hues values

Description

Rotates around the 360 degrees of hue on the HCL colour wheel,

Starts at start and rotates cycles times around the wheel to obtain n colours at equal intervals

Usage

hueSet(n = 10, start = 180, cycles = 2)

Arguments

n	number of hues to return
start	starting hue value, in degrees from 0 to 359
cycles	number of cycles rotating around the

Value

vector

Examples

hueSet()

hueSet(cycles = 1)

hueSet(start = 0, cycles = 1)

hueSet(start = 0, n = 9, cycles = 3)

---

Merge values of vector after first n unique values

Description

Merge values of vector after first n unique values

Usage

mergeAfterN(x, n, other = "other")

Arguments

x	vector
n	number of unique values/levels to keep
other	name of new value/level to replace excess values with

Value

vector

Examples

library(dplyr)
letters %>% mergeAfterN(15)
LETTERS %>% mergeAfterN(10, other = "?")

## Real data example ##
# works for factors too
gapminder::gapminder %>%
  dplyr::filter(year < 1970) %>%
  dplyr::pull(country) %>%
  mergeAfterN(10) %>%
  head(50)

---

Repeat last value in vector to create longer vector

Description

Helper function

Usage

rep_last(x, length.out)

Arguments

x	vector
length.out	desired length of vector

Examples

rep_last(letters[1:10], length.out = 15)

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