Format input values to time duration values whether those input values are numbers or of the difftime class. We can specify which time units any numeric input values have (as weeks, days, hours, minutes, or seconds) and the output can be customized with a duration style (corresponding to narrow, wide, colon-separated, and ISO forms) and a choice of output units ranging from weeks to seconds.

## Usage

fmt_duration(
data,
columns,
rows = everything(),
input_units = NULL,
output_units = NULL,
duration_style = c("narrow", "wide", "colon-sep", "iso"),
trim_zero_units = TRUE,
max_output_units = NULL,
pattern = "{x}",
use_seps = TRUE,
sep_mark = ",",
force_sign = FALSE,
system = c("intl", "ind"),
locale = NULL
)

## Arguments

data

A table object that is created using the gt() function.

columns

The columns to format. Can either be a series of column names provided in c(), a vector of column indices, or a helper function focused on selections. The select helper functions are: starts_with(), ends_with(), contains(), matches(), one_of(), num_range(), and everything().

rows

Optional rows to format. Providing everything() (the default) results in all rows in columns being formatted. Alternatively, we can supply a vector of row captions within c(), a vector of row indices, or a helper function focused on selections. The select helper functions are: starts_with(), ends_with(), contains(), matches(), one_of(), num_range(), and everything(). We can also use expressions to filter down to the rows we need (e.g., [colname_1] > 100 & [colname_2] < 50).

input_units

If one or more selected columns contains numeric values, a keyword must be provided for input_units for gt to determine how those values are to be interpreted in terms of duration. The accepted units are: "seconds", "minutes", "hours", "days", and "weeks".

output_units

Controls the output time units. The default, NULL, means that gt will automatically choose time units based on the input duration value. To control which time units are to be considered for output (before trimming with trim_zero_units) we can specify a vector of one or more of the following keywords: "weeks", "days", "hours", "minutes", or "seconds".

duration_style

A choice of four formatting styles for the output duration values. With "narrow" (the default style), duration values will be formatted with single letter time-part units (e.g., 1.35 days will be styled as "1d 8h 24m). With "wide", this example value will be expanded to "1 day 8 hours 24 minutes" after formatting. The "colon-sep" style will put days, hours, minutes, and seconds in the "([D]/)[HH]:[MM]:[SS]" format. The "iso" style will produce a value that conforms to the ISO 8601 rules for duration values (e.g., 1.35 days will become "P1DT8H24M").

trim_zero_units

Provides methods to remove output time units that have zero values. By default this is TRUE and duration values that might otherwise be formatted as "0w 1d 0h 4m 19s" with trim_zero_units = FALSE are instead displayed as "1d 4m 19s". Aside from using TRUE/FALSE we could provide a vector of keywords for more precise control. These keywords are: (1) "leading", to omit all leading zero-value time units (e.g., "0w 1d" -> "1d"), (2) "trailing", to omit all trailing zero-value time units (e.g., "3d 5h 0s" -> "3d 5h"), and "internal", which removes all internal zero-value time units (e.g., "5d 0h 33m" -> "5d 33m").

max_output_units

If output_units is NULL, where the output time units are unspecified and left to gt to handle, a numeric value provided for max_output_units will be taken as the maximum number of time units to display in all output time duration values. By default, this is NULL and all possible time units will be displayed. This option has no effect when duration_style = "colon-sep" (only output_units can be used to customize that type of duration output).

pattern

A formatting pattern that allows for decoration of the formatted value. The value itself is represented by {x} and all other characters are taken to be string literals.

use_seps

An option to use digit group separators. The type of digit group separator is set by sep_mark and overridden if a locale ID is provided to locale. This setting is TRUE by default.

sep_mark

The mark to use as a separator between groups of digits (e.g., using sep_mark = "," with 1000 would result in a formatted value of 1,000).

force_sign

Should the positive sign be shown for positive values (effectively showing a sign for all values except zero)? If so, use TRUE for this option. The default is FALSE, where only negative value will display a minus sign.

system

The numbering system to use. By default, this is the international numbering system ("intl") whereby grouping separators (i.e., sep_mark) are separated by three digits. The alternative system, the Indian numbering system ("ind") uses grouping separators that correspond to thousand, lakh, crore, and higher quantities.

locale

An optional locale ID that can be used for formatting the value according the locale's rules. Examples include "en" for English (United States) and "fr" for French (France). The use of a valid locale ID will override any values provided in sep_mark and dec_mark. We can use the info_locales() function as a useful reference for all of the locales that are supported. Any locale value provided here will override any global locale setting performed in gt()'s own locale argument.

## Value

An object of class gt_tbl.

## Targeting the values to be formatted

Targeting of values is done through columns and additionally by rows (if nothing is provided for rows then entire columns are selected). Conditional formatting is possible by providing a conditional expression to the rows argument. See the Arguments section for more information on this.

## Output units for the colon-separated duration style

The colon-separated duration style (enabled when duration_style = "colon-sep") is essentially a clock-based output format which uses the display logic of chronograph watch functionality. It will, by default, display duration values in the (D/)HH:MM:SS format. Any duration values greater than or equal to 24 hours will have the number of days prepended with an adjoining slash mark. While this output format is versatile, it can be changed somewhat with the output_units option. The following combinations of output units are permitted:

• c("minutes", "seconds") -> MM:SS

• c("hours", "minutes") -> HH:MM

• c("hours", "minutes", "seconds") -> HH:MM:SS

• c("days", "hours", "minutes") -> (D/)HH:MM

Any other specialized combinations will result in the default set being used, which is c("days", "hours", "minutes", "seconds")

## Examples

Use part of the sp500 table to create a gt table. Create a difftime-based column and format the duration values to be displayed as the number of days since March 30, 2020.

sp500 %>%
dplyr::mutate(
time_point = lubridate::ymd("2020-03-30"),
time_passed = difftime(time_point, date)
) %>%
dplyr::select(time_passed, open, close) %>%
gt(rowname_col = "month") %>%
fmt_duration(
columns = time_passed,
output_units = "days",
duration_style = "wide"
) %>%
fmt_currency(columns = c(open, close))

## Function ID

3-14

Other data formatting functions: data_color(), fmt_bytes(), fmt_currency(), fmt_datetime(), fmt_date(), fmt_engineering(), fmt_fraction(), fmt_integer(), fmt_markdown(), fmt_number(), fmt_partsper(), fmt_passthrough(), fmt_percent(), fmt_roman(), fmt_scientific(), fmt_time(), fmt(), sub_large_vals(), sub_missing(), sub_small_vals(), sub_values(), sub_zero(), text_transform()