Format labels

Description

Function for formatting label appearance, e.g. axis ticks labels. This is what the top-level xaxl and yaxl arguments from tinyplot ultimately get passed to.

Usage

tinylabel(x, labeller = NULL, na.ignore = TRUE, na.rm = TRUE)

Arguments

x	a numeric or character vector
labeller	a formatting function to be applied to x, e.g. format, toupper, abs, or other custom function (including from the popular scales package). Can also be one of the following convenience strings (symbols), for which common formatting transformations are provided: “percent” (“%”), “comma” (“,”), “log” (“l”), “dollar” (“$”), “euro” (“€”), or “sterling” (“£”).
na.ignore	logical indicating whether the labelling function should ignore NA values in x. In other words, should the NA values be left as-is? Default is TRUE.
na.rm	logical indicating whether NA values should be removed from x and thus the return object too. Default is TRUE, but only evaluated if na.ignore is FALSE.

Value

a character vector of the same length as x with the transformed labels.

See Also

tinyplot

Examples

library("tinyplot")

x = 1e4
tinylabel(x, "comma")

[1] "10,000"

tinylabel(x, ",") # same

[1] "10,000"

tinylabel(x, "$") # or "dollar"

[1] "$10,000"

# invoke tinylabel from a parent tinyplot call...
#   => x/yaxl for adjusting axes tick labels
#   => legend = list(labeller = ...) for adjusting the legend labels
s77 = transform(data.frame(state.x77), Illiteracy = Illiteracy / 100)
tinyplot(Life.Exp ~ Income | Illiteracy, data = s77,
         xaxl = '$',
         legend = list(labeller = '%'))

# log example (combined with axis scaling)
tinyplot(x = 10^c(10:0), y = 0:10, type = "b",
         log = "x", xaxl = "log")

# combine with `x/yaxb` to adjust the actual tick marks ("break points")
# at the same time
tinyplot(x = 10^c(10:0), y = 0:10, type = "b",
         log = "x", xaxl = "log", xaxb = 10^c(1,3,5,7,9))

#
## custom function examples

## example I: date formatting

dat = data.frame(
  date = seq(as.Date("2000/1/1"), by = "month", length.out = 12),
  trend = 1:12 + rnorm(12, sd = 1)
)

tinyplot(trend ~ date, data = dat,
         xaxl = function(x) format(x, "%b, %Y"))

## example II: string wrapping

# create a "vectorised" version of `base::strwrap` that breaks long
# strings into new lines every 18 characters
strwrap18 = function(x) sapply(
  strwrap(x, width = 18, simplify = FALSE),
  paste,
  collapse = "\n"
)

# now demonstrate on a dataset with long y-tick labels
dat2 = data.frame(
  x = rep(rnorm(100), 3),
  y = c(
    "tinyplot is a lightweight extension of the base R graphics system.",
    "R is a language for statistical computing.",
    "Data visualization is an essential skill."
  )
)

tinyplot(y ~ x, data = dat2, type = "j",
         yaxl = strwrap18,
         theme = "bw") # use theme for horizontal labels + dynamic margin