er_plot_theme: Adjust theme/labels for an exposure-response plot

In erplots: Model-Agnostic Exposure-Response Plots

Adjust theme/labels for an exposure-response plot

Description

Set axis/legend labels, plot titles/captions, axis limits, theme objects, discrete and continuous scale objects, formatters, legend key glyph, and relative panel heights. This does not change which variable is mapped to which aesthetic.

Usage

er_plot_theme(
  object,
  xlab = NULL,
  ylab = NULL,
  strata_lab = NULL,
  title = NULL,
  subtitle = NULL,
  caption = NULL,
  xlim = NULL,
  ylim = NULL,
  theme_base = NULL,
  theme_extra = NULL,
  color_discrete = NULL,
  fill_discrete = NULL,
  color_continuous = NULL,
  fill_continuous = NULL,
  format_p = NULL,
  format_percent = NULL,
  format_number = NULL,
  draw_key = NULL,
  dodge_width = NULL,
  height_base = NULL,
  height_data = NULL,
  height_group = NULL
)

Arguments

object	Partially constructed plot (has S3 class er_plot)
xlab, ylab	Exposure/response axis label (single string).
strata_lab	Stratification legend label (single string). Errors if stratify_by wasn't set in er_plot() – there's no stratification legend to label.
title, subtitle, caption	Plot-level annotation text (single strings), applied via patchwork::plot_annotation() in er_plot_build().
xlim, ylim	Exposure/response axis limits (length-2, increasing numeric vectors, no NA). These are read lazily by every builder at build time, so it doesn't matter whether er_plot_theme() is called before or after the layers that use them. Unlike ggplot2::coord_cartesian()'s xlim/ylim, NA isn't accepted for either endpoint: object$exposure$limits/object$response$limits also drive non-cosmetic computations (e.g. the model curve's prediction grid, quantile-bin boundaries), where a NA bound has no well-defined meaning.
theme_base	A ggplot2 theme object (e.g. ggplot2::theme_minimal()) – the swappable overall visual theme, defaulting to ggplot2::theme_bw().
theme_extra	A ggplot2 theme object (e.g. from ggplot2::theme()) with additional theme tweaks layered on top of theme_base. See "Details" for its default and replacement semantics.
color_discrete, fill_discrete	A discrete ggplot2 scale object (e.g. ggplot2::scale_color_brewer(), ggplot2::scale_fill_viridis_d()), applied to every plot whose colour/fill aesthetic is mapped to the stratification variable – see "Details".
color_continuous, fill_continuous	A continuous ggplot2 scale object (e.g. ggplot2::scale_color_viridis_c(), ggplot2::scale_fill_gradient()), applied to every plot whose colour/fill aesthetic is mapped to something continuous other than the stratification variable – see "Details".
format_p, format_percent, format_number	Formatter functions (typically from ⁠scales::label_*()⁠). Used by the summary/quantile layers to format p-values/rates/means for display. Default to scales::label_pvalue(accuracy = .001, add_p = TRUE), scales::label_percent(accuracy = 1), and scales::label_number(accuracy = 0.01) respectively.
draw_key	A key-glyph function (e.g. ggplot2::draw_key_point()), passed as every geom's key_glyph argument. Defaults to ggplot2::draw_key_rect().
dodge_width	Spacing between adjacent strata's horizontal offset in the quantile layer, as a fraction of the exposure range. A single positive number; see "Details".
height_base, height_data, height_group	Relative panel heights (single positive numbers), for the base plot, data-layer panel(s), and group-layer panel(s) respectively. Default to 6, 2, and 3. Supplying only one leaves the other two unchanged.

Details

dodge_width is a stratification-layout setting used by er_style_quantile_errorbar()/er_style_quantile_pointrange() (and their ⁠_vlines⁠ variants) to separate strata horizontally within each quantile bin. It belongs in er_plot_theme() because dodging is about stratification layout, not an individual builder's visual style. Defaults to 0.015 (set in er_plot()).

Every argument defaults to NULL, meaning "leave whatever was set before unchanged". This allows repeated calls to er_plot_theme() to update only the supplied fields, like ggplot2::theme(). There is no implicit way to reset a field to the er_plot() default.

color_discrete/fill_discrete apply only when a layer's colour/ fill aesthetic is mapped to stratification. Their continuous counterparts, color_continuous/fill_continuous, apply only when the aesthetic is mapped to a continuous quantity such as density or a continuous/count response value. If a custom builder adds its own scale, supplying one of these four will add a second scale and let ggplot2 choose the later one.

theme_extra defaults to a panel border plus legend.position = "bottom". Supplying a new value fully replaces this default rather than merging with it, so re-include the border/legend-position settings too if you want to keep them alongside your own additions.

Value

The input object, with the requested theme fields updated.

See Also

er_plot(), er_style()

Examples

if (requireNamespace("erglm", quietly = TRUE)) {
  library(erglm)
  mod <- erglm_model(ae1 ~ aucss, erglm_data, family = binomial())

  # axis labels, a title, and a swapped-in theme
  erglm_data |>
    er_plot(aucss, ae1) |>
    er_plot_add_model(mod) |>
    er_plot_theme(
      xlab = "AUC at steady state",
      ylab = "P(adverse event)",
      title = "Exposure-response for adverse events",
      theme_base = ggplot2::theme_minimal()
    ) |>
    plot()

  # repeated calls accumulate: this only touches xlim/ylim, leaving
  # the labels/title/theme set above unchanged
  erglm_data |>
    er_plot(aucss, ae1) |>
    er_plot_add_model(mod) |>
    er_plot_theme(xlab = "AUC at steady state") |>
    er_plot_theme(xlim = c(0, 3000)) |>
    plot()

  # widening the stratum-dodge spacing in a stratified quantile layer
  mod2 <- erglm_model(ae1 ~ aucss + sex, erglm_data, family = binomial())
  erglm_data |>
    er_plot(aucss, ae1, stratify_by = sex) |>
    er_plot_add_model(mod2) |>
    er_plot_add_quantiles() |>
    er_plot_theme(dodge_width = 0.15, strata_lab = "Sex") |>
    plot()
}

erplots documentation built on Oct. 4, 2026, 5:06 p.m.