This transforms objects to labeller functions. Used internally by
labeller().
Arguments
- x
Object to coerce to a labeller function. If a named character vector, it is used as a lookup table before being passed on to
default. If a non-labeller function, it is assumed it takes and returns character vectors and is applied to the labels. If a labeller, it is simply applied to the labels.- default
Default labeller to process the labels produced by lookup tables or modified by non-labeller functions.
- multi_line
Whether to display the labels of multiple factors on separate lines. This is passed to the labeller function.
Examples
p <- ggplot(mtcars, aes(disp, drat)) + geom_point()
p + facet_wrap(~am)
# Rename labels on the fly with a lookup character vector
to_string <- as_labeller(c(`0` = "Zero", `1` = "One"))
p + facet_wrap(~am, labeller = to_string)
# Quickly transform a function operating on character vectors to a
# labeller function:
appender <- function(string, suffix = "-foo") paste0(string, suffix)
p + facet_wrap(~am, labeller = as_labeller(appender))
# If you have more than one facetting variable, be sure to dispatch
# your labeller to the right variable with labeller()
p + facet_grid(cyl ~ am, labeller = labeller(am = to_string))
