Date: 2026-03-15

# Format Data Function

#### 2026-03-15

### How to use fdata()

Data can be formatted by assigning formats to the format attribute of the columns in your dataframe or tibble, and then by calling the `fdata()` function on that data. A sample program is as follows:

    # Set up data frame
    df <- mtcars[1:10, c("mpg", "cyl")]
    df

    # Define and assign formats
    attr(df$mpg, "format") <- value(condition(x >= 20, "High"),
                                    condition(x < 20, "Low"))

    attr(df$cyl, "format") <- function(x) format(x, nsmall = 1)

    # Apply formatting
    fdata(df)

Here is the mtcars subset before formatting:

    #                    mpg cyl
    # Mazda RX4         21.0   6
    # Mazda RX4 Wag     21.0   6
    # Datsun 710        22.8   4
    # Hornet 4 Drive    21.4   6
    # Hornet Sportabout 18.7   8
    # Valiant           18.1   6
    # Duster 360        14.3   8
    # Merc 240D         24.4   4
    # Merc 230          22.8   4
    # Merc 280          19.2   6

And here is the mtcars subset after formatting:

    #                    mpg cyl
    # Mazda RX4         High 6.0
    # Mazda RX4 Wag     High 6.0
    # Datsun 710        High 4.0
    # Hornet 4 Drive    High 6.0
    # Hornet Sportabout Low  8.0
    # Valiant           Low  6.0
    # Duster 360        Low  8.0
    # Merc 240D         High 4.0
    # Merc 230          High 4.0
    # Merc 280          Low  6.0

You may apply formatting to variables of any data type: character, numeric, date, etc. Internally, the `fdata()` function is using the `fapply()` function on each column in the data frame. If there is no format assigned to a column, that column is returned unaltered.

Next: Format Apply Function