Publication-Quality 'ggplot2' Geom Width

Width helper functions for publication-quality 'ggplot2' visualisation. These functions make it easier to create geoms such as bars that have a consistent width appearance across plots.

ggwidth

The objective of ggwidth is to standardise ‘ggplot2’ geom width.

It provides methods to ensure the width in ggplot2 geoms are visually consistent across plots with different numbers of categories, panel dimensions, and orientations.

It works with geoms such as geom_bar/geom_col, geom_boxplot and geom_errorbar.

Note this function requires:

a set theme with panel widths and heights specified
"x" orientation plots to have a x discrete scale with default expand
"y" orientation plots to have a y discrete scale with default expand.

Installation

Install from CRAN, or development version from GitHub.

install.packages("ggwidth") 
pak::pak("davidhodge931/ggwidth")

Example

library(ggplot2)
library(dplyr)
library(ggwidth)
library(patchwork)

set_theme(
  ggplot2::theme_grey() +
    theme(panel.widths  = rep(unit(75, "mm"), 2)) +
    theme(panel.heights = rep(unit(50, "mm"), 2))
)

p1 <- mpg |>
  ggplot(aes(x = drv)) +
  geom_bar(
    width = get_width(n = 3),
    colour = "black",
    fill = "grey",
  )

p2 <- diamonds |>
  ggplot(aes(x = color)) +
  geom_bar(
    width = get_width(n = 7),
    colour = "black",
    fill = "grey",
  )

p3 <- diamonds |>
  ggplot(aes(y = color)) +
  geom_bar(
    width = get_width(n = 7, orientation = "y"),
    colour = "black",
    fill = "grey",
  )

p4 <- mpg |>
  ggplot(aes(x = drv, group = factor(cyl))) +
  geom_bar(
    position = position_dodge(preserve = "single"),
    width = get_width(n = 3, n_dodge = 4),
    colour = "black",
    fill = "grey",
  ) 

p1 + p2 + p3 + p4

d <- tibble::tibble(
  continent = c("Europe", "Europe", "Europe", "Europe", "Europe",
                "South America", "South America"),
  country   = c("AT", "DE", "DK", "ES", "PK", "TW", "BR"),
  value     = c(10L, 15L, 20L, 25L, 17L, 13L, 5L)
)

max_n <- d |>
  count(continent) |>
  pull(n) |>
  max()

d |>
  mutate(country = forcats::fct_rev(country)) |>
  ggplot(aes(y = country, x = value)) +
  geom_col(
    width = get_width(n = max_n, orientation = "y"),
    colour = "black",
    fill = "grey",
  ) +
  facet_wrap(~continent, scales = "free_y") +
  scale_y_discrete(continuous.limits = c(1, max_n)) +
  coord_cartesian(reverse = "y", clip = "off")

mpg |>
  ggplot(aes(x = drv)) +
  geom_bar(
    width = get_width(n = 3, panel_widths = unit(160, "mm")),
    colour = "black",
    fill = "grey",
  ) +
  theme(panel.widths = unit(160, "mm"))