ggplot2: theme_get – R documentation

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theme_get

Get, set, and modify the active theme

Description

The current/active theme (see theme()) is automatically applied to every plot you draw. Use theme_get to get the current theme, and theme_set to completely override it. theme_update and theme_replace are shorthands for changing individual elements.

Usage

theme_get()

theme_set(new)

theme_update(...)

theme_replace(...)

e1 %+replace% e2

Arguments

`new`	new theme (a list of theme elements)
`...`	named list of theme settings
`e1, e2`	Theme and element to combine

Value

theme_set, theme_update, and theme_replace invisibly return the previous theme so you can easily save it, then later restore it.

Adding on to a theme

+ and %+replace% can be used to modify elements in themes.

+ updates the elements of e1 that differ from elements specified (not NULL) in e2. Thus this operator can be used to incrementally add or modify attributes of a ggplot theme.

In contrast, %+replace% replaces the entire element; any element of a theme not specified in e2 will not be present in the resulting theme (i.e. NULL). Thus this operator can be used to overwrite an entire theme.

theme_update uses the + operator, so that any unspecified values in the theme element will default to the values they are set in the theme. theme_replace uses %+replace% to completely replace the element, so any unspecified values will overwrite the current value in the theme with NULL.

In summary, the main differences between theme_set(), theme_update(), and theme_replace() are:

theme_set() completely overrides the current theme.
theme_update() modifies a particular element of the current theme using the + operator.
theme_replace() modifies a particular element of the current theme using the %+replace% operator.

Examples

p <- ggplot(mtcars, aes(mpg, wt)) +
  geom_point()
p

# Use theme_set() to completely override the current theme.
# theme_update() and theme_replace() are similar except they
# apply directly to the current/active theme.
# theme_update() modifies a particular element of the current theme.
# Here we have the old theme so we can later restore it.
# Note that the theme is applied when the plot is drawn, not
# when it is created.
old <- theme_set(theme_bw())
p

theme_set(old)
theme_update(panel.grid.minor = element_line(colour = "red"))
p

theme_set(old)
theme_replace(panel.grid.minor = element_line(colour = "red"))
p

theme_set(old)
p


# Modifying theme objects -----------------------------------------
# You can use + and %+replace% to modify a theme object.
# They differ in how they deal with missing arguments in
# the theme elements.

add_el <- theme_grey() +
  theme(text = element_text(family = "Times"))
add_el$text

rep_el <- theme_grey() %+replace%
  theme(text = element_text(family = "Times"))
rep_el$text

ggplot2

Create Elegant Data Visualisations Using the Grammar of Graphics

v3.3.3

MIT + file LICENSE

Authors

Hadley Wickham [aut] (<https://orcid.org/0000-0003-4757-117X>), Winston Chang [aut] (<https://orcid.org/0000-0002-1576-2126>), Lionel Henry [aut], Thomas Lin Pedersen [aut, cre] (<https://orcid.org/0000-0002-5147-4711>), Kohske Takahashi [aut], Claus Wilke [aut] (<https://orcid.org/0000-0002-7470-9261>), Kara Woo [aut] (<https://orcid.org/0000-0002-5125-4188>), Hiroaki Yutani [aut] (<https://orcid.org/0000-0002-3385-7233>), Dewey Dunnington [aut] (<https://orcid.org/0000-0002-9415-4582>), RStudio [cph, fnd]

Initial release