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Apply a function to each label and character/factor variable in the plot object.

Source: R/zulugg.R
gg_apply.Rd

Applies the string function fun to each label present in the plot object p, as well as to any character or factor variables in the underlying data. The function, fun, should accept and return character vectors. It can either be a simple prettifying function or it can perform more complex lookup to replace variable names with variable labels. If variables are factors, they are converted to character before applying the function after which they are reconverted to factor. Care is taken to preserve the factor ordering.

Usage

gg_apply(p, fun, ..., .labs = TRUE, .vars = TRUE)

Arguments

p

A ggplot2 object

fun

A function to be applied to the labels in p

...

Other variables to be passed to fun

.labs

logical or character, indicating whether to apply the function to the labels in p. If TRUE, apply to all character or factor variables in p. If FALSE, NULL or empty vector, do not apply the function to any variables. If a character vector containing the names of variables, apply the function to those particular variables. An error may be thrown if the vector refers to non-existing labels. Defaults to TRUE.

.vars

logical or character. If TRUE, apply to all character or factor variables in p. If FALSE, NULL or empty vector, do not apply the function to any variables. If a character vector containing the names of variables, apply the function to those particular variables. An error may be thrown if the vector refers to non-existing variables or variables that are neither characters nor factors. Defaults to TRUE.

Value

A ggplot2 object with changed labels

See also

Other functions extending ggplot: gg_apply_labs(), gg_integer_breaks()

Examples

# This uses snakecase::to_sentence_case to prettify the labels
# Note: The plot is assigned to a named variable before piping to gg_apply_labs()
#       This is to avoid issues due to the precedence of operators,
#       (%>% has higher precedence than +)
library(dplyr, warn.conflicts=FALSE)
library(ggplot2)
library(forcats)
library(snakecase)
p <- starwars %>%
    filter(mass < 1000) %>%
    mutate(species = species %>% fct_infreq %>%  fct_lump(5) %>% fct_explicit_na) %>%
    ggplot(aes(height, mass, color=species, size=birth_year)) +
    geom_point()
#> Warning: There was 1 warning in `mutate()`.
#> ℹ In argument: `species = species %>% fct_infreq %>% fct_lump(5) %>%
#>   fct_explicit_na`.
#> Caused by warning:
#> ! `fct_explicit_na()` was deprecated in forcats 1.0.0.
#> ℹ Please use `fct_na_value_to_level()` instead.
p %>% gg_apply(snakecase::to_sentence_case)
#> Warning: Removed 23 rows containing missing values (`geom_point()`).