Norwegian Punctuation Wrappers for gt, scales, and ggplot2

This post explains a set of small wrapper functions that make gt and scales output follow Norwegian punctuation rules, using commas as decimal separators and spaces before percent signs..

Background..

In Norwegian, numbers are written with a comma as the decimal separator and a space before the percent sign.. For example, what English writes as 5.5% is written as 5,5 % in Norwegian.. The gt, scales, and ggplot2 packages all default to English punctuation conventions, which makes tables and plots look wrong in a Norwegian context.. The three wrapper functions below solve this by setting sensible Norwegian defaults while still passing all other arguments through to the underlying functions..

The functions..

gt_no <- function(., locale = "no", ...) {
  gt(., locale = locale, ...)
}

fmt_percent_no <- function(., locale = "no", incl_space = TRUE, ...) {
  fmt_percent(., locale = locale, incl_space = incl_space, ...)
}

prosenten <- function(x, accuracy = NULL, scale = 100, prefix = "",
                      suffix = " %", big.mark = NULL, decimal.mark = ",",
                      trim = TRUE, ...) {
  scales::number(x = x, accuracy = accuracy, scale = scale,
                 prefix = prefix, suffix = suffix,
                 big.mark = big.mark, decimal.mark = decimal.mark,
                 trim = trim, ...)
}

gt_no..

gt_no is a thin wrapper around gt::gt().. Its only job is to change the default value of the locale argument from NULL to "no".. When gt knows the locale is Norwegian it automatically applies Norwegian number formatting rules throughout the table, including comma as the decimal separator.. Because the function uses ..., every other argument accepted by gt() can still be passed in normally..

# Instead of writing:
gt(data, locale = "no")

# You can write:
gt_no(data)

fmt_percent_no..

fmt_percent_no wraps gt::fmt_percent().. It changes two defaults: the locale is set to "no" and incl_space is set to TRUE.. The incl_space argument controls whether a space is inserted between the number and the percent sign.. Norwegian style requires this space, so 5.5% becomes 5,5 % when both defaults are applied.. Again, ... lets you pass any additional formatting arguments straight through to fmt_percent()..

# Instead of writing:
gt_no(data) |>
  fmt_percent(columns = rate, locale = "no", incl_space = TRUE)

# You can write:
gt_no(data) |>
  fmt_percent_no(columns = rate)

prosenten..

prosenten (“the percent” in Norwegian) is a wrapper around scales::number().. It is designed for use inside ggplot2 scale functions such as scale_y_continuous(labels = ...), where you pass a labelling function rather than applying formatting to a gt table.. The scales package provides scales::percent() for this purpose, but that function defaults to English conventions.. prosenten changes the defaults so that:

• scale = 100 multiplies raw proportions (0–1) by 100 before displaying them..
• suffix = " %" adds a space before the percent sign..
• decimal.mark is set as “,”
• big.mark is left as NULL, which lets scales::number() pick them up from the locale if set, or fall back to its own defaults..

# Use in a ggplot2 axis:
ggplot(data, aes(x = group, y = rate)) +
  geom_col() +
  scale_y_continuous(labels = prosenten)

Why wrapper functions..

Wrapper functions like these are a simple and low-cost way to enforce a house style.. Instead of remembering to add locale = "no" and incl_space = TRUE every time, you write the correct defaults once and reuse the wrapper everywhere.. The ... idiom ensures you do not lose any flexibility: all arguments of the original function remain available, and the wrappers stay short enough to read at a glance..