euformat

The euformat package provides a lightweight way to:

• store numbers as real numeric values,
• but print them using European number formatting:
  • comma for decimals
  • dot for thousands
  • optional euro currency symbol (” €“)

Formatted numbers behave exactly like numeric* in calculations; only printing changes.

The package works consistently in:

• R console
• base data.frames
• tibbles
• DT tables

and includes a global toggle to enable/disable printing.

Installation

You can install the development version of euformat from GitHub with:

# install.packages("pak")
pak::pak("icg-cat/euformat")

library(ggplot2)
library(tibble)
library(DT)
library(euformat)

Basic usage

Create EU-formatted numbers

x <- eu_num(c(1234.567, 10.2))
x
#> [1] "1.234,57" "10,20"

Internally still numeric:

is.numeric(x)
#> [1] TRUE
x + 1
#> [1] "1.235,57" "11,20"

Currency formatting

eu_currency(c(1500, 20000))
#> [1] "1.500,00 €"  "20.000,00 €"

Vectorized decimal digits

eu_num(c(1.2345, 2.34567), digits = c(1, 3))
#> [1] "1,2"   "2,346" "1,2"   "2,346"

Using euformat inside tibbles

tibble(value = eu_num(c(1234.5, 98765.432)))
#> # A tibble: 2 × 1
#>       value
#>    <eu_num>
#> 1  1.234,50
#> 2 98.765,43

Using euformat in base data frames

data.frame(amount = eu_currency(c(1234.5, 98765.4)))
#>        amount
#> 1  1.234,50 €
#> 2 98.765,40 €

Formatting in DT tables

df <- cbind(
  item  = c("A", "B", "C", "D"),
  value = c(2, 10, 1000.5, 12.34), 
  cost  = (c(2, 10, 1000.5, 12.34) * 1.3)
)

datatable(df) |>
  dt_format_eu(columns = c("value", "cost"), digits = 2, currency = TRUE)

Numeric format is maintained, so further developments can be added to the table:

datatable(
  df,
  container = htmltools::withTags(
    table(
      tableHeader(df),
      tableFooter(c("Total", "", ""))  # footer placeholders
    )
  ),
  options = list(
    footerCallback = JS(
      "function(tfoot, data, start, end, display) {",
      "  var api = this.api();",

      "  // numeric totals for value and cost",
      "  var total_value = api.column(1, { page: 'current' }).data().reduce(function(a,b){",
      "    return a + parseFloat(b) || 0;",
      "  }, 0);",

      "  var total_cost = api.column(2, { page: 'current' }).data().reduce(function(a,b){",
      "    return a + parseFloat(b) || 0;",
      "  }, 0);",

      "  // write totals into footer",
      "  $(api.column(0).footer()).html('Total');",
      "  $(api.column(1).footer()).html(total_value);",
      "  $(api.column(2).footer()).html(total_cost);",
      "}"
    )
  )
) |> dt_format_eu(columns = c("value", "cost"), digits = 2, currency = TRUE)

Formatting in ggplot2

# Example data
df <- data.frame(
  category = LETTERS[1:5],
  revenue  = c(1234.5, 56789, 101112.3, 2000, 300.75)
)

# Plain EU number formatting
p1 <- ggplot(df, aes(category, revenue)) +
  geom_col(fill = "#4477AA") +
  eu_scale_y() +
  ggtitle("Revenue with EU-style number formatting")

# EU currency formatting
p2 <- ggplot(df, aes(category, revenue)) +
  geom_col(fill = "#66CCAA") +
  eu_scale_y(currency = TRUE) +
  ggtitle("Revenue with EU-style currency formatting")

p1

p2

Turning formatting on and off

eu_format_off()
x
#> [1] 1234.567   10.200
#> attr(,"digits")
#> [1] 2 2
#> attr(,"currency")
#> [1] FALSE
#> attr(,"class")
#> [1] "eu_num"  "numeric"

eu_format_on()
x
#> [1] "1.234,57" "10,20"

This affects printing only; underlying data remain numeric.