Package {ggCheysson}

Title:	Graphic Styles of Emile Cheysson for 'ggplot2'
Version:	1.1.0
Date:	2026-09-28
Description:	Implements for 'ggplot2' the stylistic elements (fonts, hatched patterns, color palettes) used by 'Emile Cheysson' in the 'Albums de Statistique Graphique', sometimes called the pinnacle of the Golden Age of Statistical Graphics.
Imports:	ggplot2
Suggests:	ggpattern, ggthemes, gridpattern, systemfonts, showtext, sysfonts, ragg, knitr, rmarkdown, Guerry, sf, tidyr, dplyr
License:	GPL (≥ 3)
Language:	en-US
Encoding:	UTF-8
URL:	https://github.com/friendly/ggCheysson, https://friendly.github.io/ggCheysson/
BugReports:	https://github.com/friendly/ggCheysson/issues
Depends:	R (≥ 3.5)
LazyData:	true
VignetteBuilder:	knitr
Config/roxygen2/version:	8.1.0
NeedsCompilation:	no
Packaged:	2026-09-30 18:49:34 UTC; friendly
Author:	Michael Friendly [aut, cre], RJ Andrews [ctb], Tom Shanley [ctb], Kenneth Fields [ctb]
Maintainer:	Michael Friendly <friendly@yorku.ca>
Repository:	CRAN
Date/Publication:	2026-10-01 08:10:24 UTC

Album Images Metadata

Description

Metadata linking the 25 color palettes from the Albums de Statistique Graphique to their corresponding album years, plate numbers, and David Rumsey collection reference numbers.

Usage

albumImages

Format

A data frame with 25 rows and 6 variables:

adventDay

Advent calendar day number (1-25) from original digitization

RumseyListNo

David Rumsey Map Collection list number

Album

Year of the album (1880-1906)

Qty

Number of colors/pattern elements in the palette - not a plate identifier (see cheysson_palettes for the actual unique plate number, derived from RumseyListNo's decimal suffix)

Type

Palette type: "Sequential", "Diverging", "Grouped", or "Category"

link

URL to the digitized image in the David Rumsey Map Collection

Details

This dataset provides the mapping between the original SVG pattern files (named by Advent calendar days by RJ Andrews) and the actual album years and plate numbers from the Albums de Statistique Graphique.

The naming convention "adventDay" comes from RJ Andrews' original digitization project where he released one palette per day during December as an Advent calendar. The package uses the Album year and plate number for more intuitive palette naming (e.g., "1880_07" instead of "dec06"). The plate number is derived from RumseyListNo's decimal suffix (e.g. "12511.007" -> 7), which is the real unique per-plate identifier - not Qty, which is a count of colors/pattern elements in the palette and can repeat across genuinely different plates.

Source

• David Rumsey Map Collection: https://www.davidrumsey.com/

• RJ Andrews Album Colors: https://github.com/infowetrust/albumcolors

• Tom Shanley Observable: https://web.archive.org/web/20210130125506/https://observablehq.com/@tomshanley/cheysson-color-palettes

See Also

cheysson_palettes, cheysson_patterns

Examples

# View the dataset
head(albumImages)

# Find information about a specific album
subset(albumImages, Album == 1880)

# Count palettes by type
table(albumImages$Type)

# Get the Rumsey link for a specific palette
albumImages[albumImages$Album == 1881 & albumImages$Qty == 3, "link"]

Get Cheysson font family name

Description

Returns the appropriate Cheysson font family name for a given purpose.

Usage

cheysson_font(type = c("regular", "italic", "sans", "outline", "title"))

Arguments

Value

Character string with font family name

Examples

cheysson_font("title")  # Returns "CheyssonTitle"
cheysson_font("regular")  # Returns "Cheysson"

Correction factor for a Cheysson display font's undersized metrics

Description

The four non-body Cheysson font families (CheyssonSansCaps, CheyssonTitle, CheyssonItalic, CheyssonOutlineCaps) each measure smaller than a typical sans font (Arial) at the same nominal point size - a common trait of hand-drawn/all-caps/decorative designs, which have less ascender/descender space filling out the type's em box. Sizes for text set in one of these families are scaled up by this factor so they read at roughly the intended visual size, rather than shrinking further on top of an already-undersized glyph. Factors were derived from systemfonts::font_info() (max_ascend, lineheight vs Arial at size 11), landing between the ascent-ratio-implied and lineheight-ratio-implied corrections for each family; CheyssonSansCaps and CheyssonTitle were additionally checked against rendered comparisons (see dev/fonts/test_title_size_fix.R).

Usage

cheysson_font_size_adjust(family)

Arguments

Value

A numeric scaling factor (1 if family isn't one of the four known undersized display fonts).

Cheysson Font Families

Description

Metadata about the five Cheysson font families included in the package, describing their characteristics and recommended uses.

Usage

cheysson_fonts

Format

A data frame with 5 rows and 4 variables:

family

Font family name (e.g., "Cheysson", "CheyssonTitle")

description

Brief description of the font style

use

Recommended use cases for the font

file

TrueType font filename in the inst/fonts/ directory

Details

The package includes five hand-drawn font families created by Kenneth Fields (ESRI) to match the lettering style of the original Albums de Statistique Graphique:

• Cheysson: Regular serif font suitable for body text, axis labels, and legends

• CheyssonItalic: Italic variant for emphasis and annotations

• CheyssonSansCaps: Sans-serif capitals for axis labels and category names

• CheyssonOutlineCaps: Outlined capitals for decorative plot titles and headings

• CheyssonTitle: Decorative font for main plot titles

These fonts must be loaded before use with load_cheysson_fonts(). The Cheysson themes (theme_cheysson(), etc.) automatically select appropriate fonts for different plot elements.

Source

Font families created by Kenneth Fields (ESRI) based on the lettering style of Émile Cheysson's Albums de Statistique Graphique.

See Also

load_cheysson_fonts(), cheysson_fonts_available(), theme_cheysson()

Examples

# View font metadata
cheysson_fonts

# Get recommended uses
cheysson_fonts[, c("family", "use")]

# Find the title font
subset(cheysson_fonts, grepl("title", use, ignore.case = TRUE))

Check if Cheysson fonts are loaded

Description

Checks whether Cheysson fonts have been registered and are available for use.

Usage

cheysson_fonts_available(method = NULL)

Arguments

Value

Logical indicating whether fonts are available

Examples

if (cheysson_fonts_available()) {
  message("Cheysson fonts are ready to use!")
}

Cheysson Palette Naming Crosswalk

Description

A one-row-per-plate lookup table tying together every naming scheme used for these 25 palettes: the package's own cheysson_palettes/ cheysson_patterns names, RJ Andrews' original Advent calendar labels, and Tom Shanley's Observable notebook IDs. Useful whenever you have a palette identified in someone else's terms - an Advent day, a David Rumsey catalog number, or a label copied from Andrews' or Shanley's own work - and need the package name to actually use it in scale_color_cheysson() and friends, or vice versa (see cheysson_name() for a lookup function that does this translation for you).

Usage

cheysson_labels

Format

A data frame with 25 rows and 10 variables:

name

The package's current palette name (e.g. "1881_22") - pass this to scale_color_cheysson(), cheysson_pal(), cheysson_pattern(), etc. Unique; matches names(cheysson_palettes) and names(cheysson_patterns) exactly

advent_day

Advent calendar day (1-25) from RJ Andrews' original digitization project, where he released one palette per day during December

album_year

Year of the album (1880-1906)

plate

The plate number within the album, derived from rumsey_no's decimal suffix (e.g. "12511.007" -> 7) - the real unique per-plate identifier that name is built from

type

Palette type: "Sequential", "Diverging", "Grouped", or "Category"

qty

Number of colors/pattern elements in the palette - despite the name, not a plate identifier (see plate)

rumsey_no

David Rumsey Map Collection list number

old_name

The name this palette would have received under the package's original (Album + qty) naming scheme, before a 2026-09-16 fix - kept for historical reference. Not unique: 4 pairs of genuinely different plates shared an old_name, silently overwriting one another during data extraction until the fix

andrews_label

RJ Andrews' own label for this palette, in the form "Dec.DD-YYYY.PP" (Advent day - album year . plate)

shanley_id

Tom Shanley's Observable notebook ID for this palette: type followed directly by rumsey_no's digits with the dot removed (e.g. "diverging12514021")

Details

This table exists because the package's own name (Album + plate) is a convenient but package-internal convention - it isn't what you'll see if you're reading Andrews' or Shanley's original write-ups, or working from a Rumsey catalog reference. andrews_label and shanley_id are derived programmatically from the verified rule linking all three schemes (album year + plate, taken from rumsey_no's decimal suffix), not scraped from either source - both were cross-checked against every legible label/ID in the reference images below and matched for all 24/24 checked. (Two of Shanley's own ID strings have isolated typos - a digit transposition and a missing trailing digit; his prose descriptions don't have these typos, and this table's shanley_id gives the corrected form, not the typo'd one.)

old_name also documents a real bug this table helped uncover: before 2026-09-16, palette names were built from qty (a color count) instead of plate (the real per-plate identifier), causing 4 collisions between genuinely different plates and silently dropping 5 of the original 25 palettes from the package. Comparing name to old_name shows exactly what changed for each plate.

Source

• David Rumsey Map Collection: https://www.davidrumsey.com/

• RJ Andrews Album Colors: https://github.com/infowetrust/albumcolors - see also man/figures/RJ-Andrews-color-palettes.jpg in the package sources for his own reference grid of all 25 labeled palettes

• Tom Shanley Observable: https://web.archive.org/web/20210130125506/https://observablehq.com/@tomshanley/cheysson-color-palettes - see also man/figures/shanley-palettes.png in the package sources for his own reference grid of all 25 labeled palettes

• data-raw/observable/albumColors.csv (this package) - the original Advent day / Rumsey number / album / type mapping everything else here is derived from

See Also

cheysson_palettes, cheysson_patterns, albumImages, cheysson_name()

Examples

# View the crosswalk
head(cheysson_labels)

# Find the package name for a palette described in Andrews' terms
cheysson_labels[cheysson_labels$andrews_label == "Dec.01-1883.21", "name"]

# Find the package name for a palette described in Shanley's terms
cheysson_labels[cheysson_labels$shanley_id == "grouped12511007", "name"]

# See what a palette used to be called before the 2026-09-16 naming fix
subset(cheysson_labels, name != old_name)[, c("name", "old_name")]

Translate a palette label from another naming scheme to the current name

Description

Looks up a palette by whichever label you have it in - the package's own (possibly outdated) name, RJ Andrews' Advent-calendar label, Tom Shanley's Observable notebook ID, a David Rumsey catalog number, or an advent day - and returns the current name to pass to scale_color_cheysson(), cheysson_pal(), cheysson_pattern(), and friends.

Usage

cheysson_name(
  label,
  from = c("auto", "name", "andrews", "shanley", "rumsey_no", "old_name"),
  advent_day = NULL
)

Arguments

Details

Before ggCheysson 1.1.0, 4 different old_name values were each used by 2-3 genuinely different palettes (a naming collision bug - see cheysson_labels), so translating from old_name alone can be ambiguous. When it is, cheysson_name() returns the palette that actually shipped under that name in 1.0.1 (the one with the highest advent_day among the candidates - this is what the pre-fix extraction logic itself picked) and issues a warning() listing every candidate it did not return. Pass advent_day explicitly to get a different one without a warning.

Value

A character string: the current palette name.

See Also

cheysson_labels

Examples

# RJ Andrews' label -> current name
cheysson_name("Dec.01-1883.21")

# Tom Shanley's ID -> current name
cheysson_name("diverging12514021")

# An old (pre-1.1.0) name that's unambiguous
cheysson_name("1883_04", from = "old_name")

# An old name that collided across 2 palettes: returns the one that
# shipped under this name in 1.0.1, with a warning
cheysson_name("1880_07", from = "old_name")

# Disambiguate explicitly - no warning
cheysson_name("1880_07", from = "old_name", advent_day = 6)

Get a Cheysson color palette

Description

Returns colors from a specified Cheysson palette. Palettes can be referenced by name (e.g., "1880_21") or by selecting a palette of a particular type.

Usage

cheysson_pal(palette = "1880_21", n = NULL, type = 1)

Arguments

Value

A character vector of hex color codes

Examples

# Get all colors from a specific palette
cheysson_pal("1880_21")

# Get 5 colors from a palette
cheysson_pal("1880_21", n = 5)

# Get colors from first sequential palette
cheysson_pal("sequential")

# Get colors from second category palette
cheysson_pal("category", type = 2)

Cheysson Color Palettes

Description

Color palettes extracted from the Albums de Statistique Graphique produced under the direction of Émile Cheysson. These palettes are organized by album year and plate number.

Usage

cheysson_palettes

Format

A list of 25 color palettes, each containing:

colors

Character vector of hex color codes

type

Palette type: "sequential", "diverging", "grouped", or "category"

album

Year of the album

plate

Plate number within the album

rumsey_no

David Rumsey collection reference number

dec_day

Advent calendar day from original source

Details

The palettes are named using the convention YYYY_PP where YYYY is the album year and PP is the zero-padded plate number. For example, "1880_07" refers to plate 7 from the 1880 album.

Palette types:

• Sequential (7 palettes): Ordered colors for quantitative data

• Diverging (2 palettes): Two contrasting colors with neutral midpoint

• Grouped (10 palettes): Related colors for comparing groups

• Category (6 palettes): Distinct colors for categorical data

Palette order: sequential palettes are stored from low to high (light to dark), and diverging palettes from one extreme through the neutral middle to the other, so reverse = TRUE in the scales flips the direction the same way for every palette. Category and grouped palettes keep the order of RJ Andrews' swatches. (⁠1886_26⁠, typed "sequential" in the source, has two hues and no single light-to-dark order.) Some sequential palettes, such as ⁠1881_12⁠, have a single color: their steps are in the hatching, see cheysson_patterns.

Source

Color patterns digitized by RJ Andrews from the David Rumsey Map Collection https://github.com/infowetrust/albumcolors

Observable implementation by Tom Shanley https://web.archive.org/web/20210130125506/https://observablehq.com/@tomshanley/cheysson-color-palettes

See Also

cheysson_pal(), scale_color_cheysson()

Examples

# List available palettes
names(cheysson_palettes)

# Get colors from a specific palette
cheysson_palettes$`1880_07`$colors

# Find palettes by type
sequential_pals <- Filter(function(x) x$type == "sequential", cheysson_palettes)
names(sequential_pals)

Get Cheysson pattern specifications

Description

Returns pattern specifications from a Cheysson palette for use with ggpattern.

Usage

cheysson_pattern(palette = "1881_12", n = NULL, type = 1)

Arguments

Value

A list of pattern specifications suitable for ggpattern

Examples

# Get all patterns from a palette
cheysson_pattern("1881_12")

# Get first 3 patterns
cheysson_pattern("1881_12", n = 3)

# Get patterns from a sequential palette
cheysson_pattern("sequential")

Create ggpattern-compatible pattern parameters

Description

Converts Cheysson pattern specifications to parameters suitable for ggpattern geoms.

Usage

cheysson_pattern_params(patterns, param = "fill")

Arguments

Value

Vector of parameter values

Examples

patterns <- cheysson_pattern("1881_12")
cheysson_pattern_params(patterns, "fill")
cheysson_pattern_params(patterns, "pattern_angle")

Cheysson Pattern Data

Description

Pattern specifications (fills and hatching) extracted from the Albums de Statistique Graphique. These patterns combine solid colors with line hatching (stripes and crosshatching) as used in Cheysson's maps.

Usage

cheysson_patterns

Format

A list of 25 pattern palettes, each containing:

patterns

List of pattern specifications with fill colors and hatching parameters

type

Palette type: "sequential", "diverging", "grouped", or "category"

album

Year of the album

plate

Plate number within the album

rumsey_no

David Rumsey collection reference number

dec_day

Advent calendar day from original source

n_patterns

Number of patterns in the palette

Details

Each pattern specification includes:

• type: "solid", "stripe", or "crosshatch"

• fill: Base fill color

• pattern_fill: Color for pattern lines

• pattern_angle: Angle of stripes (in degrees)

• pattern_density: Density of pattern lines (0-1)

• pattern_spacing: Spacing between pattern lines

• pattern_linewidth: Width of pattern lines

Patterns are stored in the same order as cheysson_palettes: sequential palettes from low to high (lightest hatching to solid), diverging palettes end to end with the solid fills at the extremes.

Source

Pattern specifications digitized from the David Rumsey Map Collection

See Also

cheysson_pattern(), scale_pattern_fill_cheysson()

Examples

# List available pattern palettes
names(cheysson_patterns)

# Get patterns from a specific palette
cheysson_patterns$`1881_12`

Extract pattern parameters for ggpattern

Description

Helper function to extract specific pattern parameters from a pattern spec.

Usage

get_pattern_param(pattern_spec, param, default = NA)

Arguments

Value

The parameter value or default

List available Cheysson palettes

Description

Returns information about available Cheysson color palettes, optionally filtered by type.

Usage

list_cheysson_pals(type = NULL)

Arguments

Value

A data frame with columns: name, type, album, plate, n_colors

Examples

# List all palettes
list_cheysson_pals()

# List only sequential palettes
list_cheysson_pals("sequential")

# List only category palettes
list_cheysson_pals("category")

List available Cheysson pattern palettes

Description

Returns information about available Cheysson pattern palettes.

Usage

list_cheysson_patterns(type = NULL)

Arguments

Value

A data frame with columns: name, type, album, plate, n_patterns

Examples

# List all pattern palettes
list_cheysson_patterns()

# List only sequential palettes
list_cheysson_patterns("sequential")

Load Cheysson fonts

Description

Registers the Cheysson font families for use in plots. This function should be called before using Cheysson fonts in ggplot2.

Usage

load_cheysson_fonts(method = c("systemfonts", "showtext"))

Arguments

Details

The package includes five Cheysson font families:

• Cheysson: Regular serif font for body text

• CheyssonItalic: Italic variant

• CheyssonSansCaps: Sans-serif capitals

• CheyssonOutlineCaps: Outlined capitals for titles

• CheyssonTitle: Decorative font for titles

When using showtext, you must call showtext::showtext_auto() before creating plots, and showtext::showtext_auto(FALSE) when done.

Windows users: The systemfonts method works for saved plots (with ragg) but custom fonts won't appear in the on-screen plot window. For on-screen preview with fonts:

• Use method = "showtext" instead, or

• In RStudio: Tools > Global Options > General > Graphics > Backend: "AGG"

For saving plots with systemfonts, use ggsave(..., device = ragg::agg_png).

Value

Invisibly returns a character vector of loaded font family names

Examples

# Load fonts (default method)
load_cheysson_fonts()

# Use in a plot
library(ggplot2)
p <- ggplot(mtcars, aes(wt, mpg)) +
  geom_point() +
  labs(title = "Using Cheysson Fonts") +
  theme(
    text = element_text(family = "Cheysson"),
    plot.title = element_text(family = "CheyssonTitle")
  )

# Save to temporary file
tmp <- tempfile(fileext = ".png")
if (requireNamespace("ragg", quietly = TRUE)) {
  ggsave(tmp, p, device = ragg::agg_png)
} else {
  ggsave(tmp, p)
}
unlink(tmp)

Apply a Cheysson color-and-pattern palette in one step

Description

Experimental. The interface of scale_cheysson() and aes_cheysson() may change in a future version.

Usage

scale_cheysson(
  palette = "1881_12",
  reverse = FALSE,
  aesthetics = c("fill", "pattern", "pattern_fill", "pattern_fill2", "pattern_angle"),
  na.value = "grey80",
  ...
)

aes_cheysson(x, ...)

Arguments

Details

Cheysson's palettes combine colors with hatching: each element of a palette has a paper or fill color, a hatch type (solid, stripe or crosshatch), a line color and an angle. Drawing them with 'ggpattern' takes one scale per aesthetic (scale_fill_cheysson_pattern(), scale_pattern_type_cheysson(), scale_pattern_fill_cheysson(), ...). scale_cheysson() adds all of them with a single +, and aes_cheysson() maps one variable to all of the matching aesthetics.

All the scales take their values from the same elements of the palette, so each level of the mapped variable gets one complete historical swatch. The aesthetics must be mapped for the scales to apply: a scale for pattern_fill does nothing unless pattern_fill is mapped, and 'ggpattern' then draws grey hatching. aes_cheysson() maps them all.

Parameters that are better set to fixed values in the geom are not included: pattern_density and pattern_spacing (the palettes' spacings were measured on small swatches, see the Guerry maps vignette), pattern_colour (NA avoids outlines around the hatch lines) and the outline colour.

Value

scale_cheysson() returns a list of ggplot2 discrete scales, which can be added to a plot with + like a single scale.

aes_cheysson() returns an aesthetic mapping of x to fill, pattern, pattern_fill, pattern_fill2 and pattern_angle, plus any mappings in ....

See Also

scale_pattern_cheysson for the individual scales, cheysson_pattern() for the underlying pattern specifications.

Examples

if (requireNamespace("ggpattern", quietly = TRUE)) {
  library(ggplot2)
  library(ggpattern)

  data <- data.frame(
    category = LETTERS[1:5],
    value = c(15, 23, 18, 20, 12)
  )

  ggplot(data, aes(category, value)) +
    geom_col_pattern(aes_cheysson(category),
                     pattern_colour = NA, pattern_density = 0.35,
                     colour = "black") +
    scale_cheysson("1883_30") +
    theme_minimal()
}

Cheysson color scales for ggplot2

Description

Color and fill scales using Cheysson palettes from the Albums de Statistique Graphique.

Usage

scale_color_cheysson(
  palette = "1880_21",
  discrete = TRUE,
  reverse = FALSE,
  ...
)

scale_colour_cheysson(
  palette = "1880_21",
  discrete = TRUE,
  reverse = FALSE,
  ...
)

scale_fill_cheysson(palette = "1880_21", discrete = TRUE, reverse = FALSE, ...)

Arguments

Value

A ggplot2 scale object that can be added to a plot. For discrete scales, returns a discrete_scale object. For continuous scales, returns a continuous scale object (gradient).

Examples

library(ggplot2)

# Discrete color scale
ggplot(iris, aes(Sepal.Length, Sepal.Width, color = Species)) +
  geom_point() +
  scale_color_cheysson()

# Use a specific palette
ggplot(iris, aes(Sepal.Length, Sepal.Width, color = Species)) +
  geom_point() +
  scale_color_cheysson(palette = "1881_22")

# Use a sequential palette for continuous data
ggplot(iris, aes(Sepal.Length, Sepal.Width, color = Petal.Length)) +
  geom_point() +
  scale_color_cheysson(palette = "sequential", discrete = FALSE)

# Fill scale with category colors
ggplot(iris, aes(Species, Sepal.Width, fill = Species)) +
  geom_boxplot() +
  scale_fill_cheysson(palette = "category")

Apply Cheysson patterns to fill aesthetic

Description

Convenience function that applies the base fill color from Cheysson patterns. Use in combination with pattern_* scales for full pattern effect.

Usage

scale_fill_cheysson_pattern(palette = "1881_12", reverse = FALSE, ...)

Arguments

Value

A ggplot2 discrete scale object for the fill aesthetic. Applies the base fill colors from Cheysson patterns.

Examples

# Requires ggpattern package
if (requireNamespace("ggpattern", quietly = TRUE)) {
  library(ggplot2)
  library(ggpattern)

  data <- data.frame(
    category = LETTERS[1:4],
    value = c(15, 23, 18, 20)
  )

  ggplot(data, aes(category, value, fill = category)) +
    geom_col_pattern(aes(pattern = category)) +
    scale_fill_cheysson_pattern("category") +
    scale_pattern_type_cheysson("category") +
    theme_minimal()
}

Cheysson pattern scales for ggpattern

Description

Pattern fill scales using Cheysson patterns from the Albums de Statistique Graphique. These scales work with ggpattern geoms to apply both colors and hatching patterns.

Usage

scale_pattern_fill_cheysson(palette = "1881_12", reverse = FALSE, ...)

scale_pattern_fill2_cheysson(palette = "1881_12", reverse = FALSE, ...)

scale_pattern_type_cheysson(palette = "1881_12", reverse = FALSE, ...)

scale_pattern_angle_cheysson(palette = "1881_12", reverse = FALSE, ...)

scale_pattern_density_cheysson(palette = "1881_12", reverse = FALSE, ...)

Arguments

Details

These scales require the ggpattern package. Use with ggpattern geoms like geom_col_pattern(), geom_bar_pattern(), etc.

The scales apply multiple pattern aesthetics simultaneously:

• fill: Base fill color

• pattern: Type of pattern (none, stripe, crosshatch) - set via scale_pattern_type_cheysson(), which targets ggpattern's pattern aesthetic

• pattern_fill: Color of pattern lines

• pattern_fill2: Color of a crosshatch's second set of lines (differs from pattern_fill only in the two-color crosshatches of ⁠1883_30⁠ and ⁠1886_17⁠)

• pattern_angle: Angle of stripes

• pattern_density: Density of pattern lines

For a sequential or diverging palette with more patterns than the data has levels, the scales use patterns spread over the whole palette (keeping both ends), not the first ones. See cheysson_patterns for the stored order.

Value

A ggplot2 discrete scale object for the specified pattern aesthetic (pattern_fill, pattern_fill2, pattern, pattern_angle, or pattern_density). These scales apply the historically accurate Cheysson patterns to ggpattern geoms.

Examples

# Requires ggpattern package
if (requireNamespace("ggpattern", quietly = TRUE)) {
  library(ggplot2)
  library(ggpattern)

  # Basic bar chart with patterns
  data <- data.frame(
    category = LETTERS[1:4],
    value = c(15, 23, 18, 20)
  )

  ggplot(data, aes(category, value, fill = category)) +
    geom_col_pattern(
      aes(
        pattern = category,
        pattern_fill = category,
        pattern_angle = category
      ),
      pattern_density = 0.3,
      color = "black"
    ) +
    scale_pattern_fill_cheysson("category") +
    scale_pattern_type_cheysson("category") +
    scale_pattern_angle_cheysson("category") +
    theme_minimal()
}

Display a Cheysson palette with color swatches and hex codes

Description

Creates a visual display of a color palette showing color swatches along with their hex codes. This is useful for documentation, presentations, and exploring the available palettes.

Usage

show_palette(palette = "1880_21", n = NULL, show_info = TRUE, cex = 1)

Arguments

Value

Invisibly returns a character vector of the displayed hex codes. The function is called primarily for its side effect of creating a plot.

Examples

# Display a specific palette
show_palette("1880_21")

# Display palette without metadata
show_palette("1881_30", show_info = FALSE)

# Display 10 interpolated colors
show_palette("1895_16", n = 10)

# Display first sequential palette
show_palette("sequential")

Display multiple Cheysson palettes

Description

Creates a visual display of multiple color palettes, useful for comparing palettes or showing all palettes of a certain type.

Usage

show_palettes(palettes = NULL, ncol = 1, cex = 0.8)

Arguments

Value

Invisibly returns NULL. The function is called for its side effect of creating a plot.

Examples

# Show all sequential palettes (use ncol > 1 to keep panels legible with
# several palettes; a tall single-column layout can also fail to render
# when captured for the pkgdown reference site)
show_palettes("sequential", ncol = 2)

# Show specific palettes
show_palettes(c("1880_21", "1883_21", "1895_16"))

Cheysson theme for ggplot2

Description

A ggplot2 theme inspired by the visual style of the Albums de Statistique Graphique, using Cheysson fonts and appropriate styling.

Usage

theme_cheysson(
  base_size = 11,
  base_family = "auto",
  title_family = "auto",
  axis_title_family = "auto",
  load_fonts = TRUE
)

Arguments

Details

This theme applies the following styling:

• Cheysson fonts for all text elements

• Minimal grid lines

• Classic axis styling

• Subtle colors matching historical aesthetics

Font selection:

• Plot title: CheyssonTitle (decorative)

• Axis titles: CheyssonSansCaps (capitals)

• Body text: Cheysson (regular)

Value

A ggplot2 theme object

Examples

## Not run: 
# Not run automatically: rendering text with a Cheysson font registered via
# systemfonts can crash grid with "invalid font type" on some graphics
# devices (reproduced under R CMD check --as-cran); works fine interactively.
library(ggplot2)

# Load fonts first (required for proper rendering)
load_cheysson_fonts()

# Basic usage
ggplot(mtcars, aes(wt, mpg)) +
  geom_point() +
  labs(title = "Automobile Statistics") +
  theme_cheysson()

# With Cheysson color palette
ggplot(iris, aes(Sepal.Length, Sepal.Width, color = Species)) +
  geom_point(size = 3) +
  scale_color_cheysson("1881_22") +
  theme_cheysson()

## End(Not run)

Cheysson map theme

Description

A theme specifically designed for maps, with no grid and minimal elements, in the style of Cheysson's cartographic works.

Usage

theme_cheysson_map(
  base_size = 11,
  base_family = "auto",
  title_family = "auto",
  load_fonts = TRUE
)

Arguments

Value

A ggplot2 theme object that can be added to a plot with +.

Examples

## Not run: 
# Not run automatically: see theme_cheysson() for why (same font/grid crash)
# once a plot with this theme is actually rendered/printed.
# For use with spatial data/maps
library(ggplot2)

# Load fonts first
load_cheysson_fonts()

# Example with spatial data (requires sf package)
if (requireNamespace("sf", quietly = TRUE)) {
  # ggplot(map_data) + geom_sf() + theme_cheysson_map()
}

## End(Not run)

Minimal Cheysson theme

Description

A more minimal version of theme_cheysson with fewer grid lines, suitable for maps and diagrams.

Usage

theme_cheysson_minimal(
  base_size = 11,
  base_family = "auto",
  title_family = "auto",
  axis_title_family = "auto",
  load_fonts = TRUE
)

Arguments

Value

A ggplot2 theme object that can be added to a plot with +.

Examples

## Not run: 
# Not run automatically: see theme_cheysson() for why (same font/grid crash).
library(ggplot2)

# Load fonts first
load_cheysson_fonts()

ggplot(mtcars, aes(wt, mpg)) +
  geom_point() +
  theme_cheysson_minimal()

## End(Not run)