fmt_date: Format values as dates
In gt: Easily Create Presentation-Ready Display Tables
fmt_date R Documentation
Format values as dates
Description
Format input values to time values using one of 41 preset date styles. Input
can be in the form of POSIXt (i.e., datetimes), the Date type, or
character (must be in the ISO 8601 form of YYYY-MM-DD HH:MM:SS or
YYYY-MM-DD).
Usage
fmt_date(
data,
columns = everything(),
rows = everything(),
date_style = "iso",
pattern = "{x}",
locale = NULL
)
Arguments
data
The gt table data object
obj:<gt_tbl> // required
This is the gt table object that is commonly created through use of the
gt() function.
columns
Columns to target
<column-targeting expression> // default: everything()
Can either be a series of column names provided in c(), a vector of
column indices, or a select helper function (e.g. starts_with(),
ends_with(), contains(), matches(), num_range() and everything()).
rows
Rows to target
<row-targeting expression> // default: everything()
In conjunction with columns, we can specify which of their rows should
undergo formatting. The default everything() 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 select helper
function (e.g. starts_with(), ends_with(), contains(), matches(),
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).
date_style
Predefined style for dates
scalar<character>|scalar<numeric|integer>(1<=val<=41) // default: "iso"
The date style to use. By default this is the short name "iso" which
corresponds to ISO 8601 date formatting. There are 41 date styles in total
and their short names can be viewed using info_date_style().
pattern
Specification of the formatting pattern
scalar<character> // default: "{x}"
A formatting pattern that allows for decoration of the formatted value. The
formatted value is represented by the {x} (which can be used multiple
times, if needed) and all other characters will be interpreted as string
literals.
locale
Locale identifier
scalar<character> // default: NULL (optional)
An optional locale identifier that can be used for formatting values
according the locale's rules. Examples include "en" for English (United
States) and "fr" for French (France). We can call info_locales() for a
useful reference for all of the locales that are supported. A locale ID can
be also set in the initial gt() function call (where it would be used
automatically by any function with a locale argument) but a locale
value provided here will override that global locale.
Value
An object of class gt_tbl.
Compatibility of formatting function with data values
fmt_date() is compatible with body cells that are of the "Date",
"POSIXt" or "character" types. Any other types of body cells are ignored
during formatting. This is to say that cells of incompatible data types may
be targeted, but there will be no attempt to format them.
Targeting cells with columns and rows
Targeting of values is done through columns and additionally by rows (if
nothing is provided for rows then entire columns are selected). The
columns argument allows us to target a subset of cells contained in the
resolved columns. We say resolved because aside from declaring column names
in c() (with bare column names or names in quotes) we can use
tidyselect-style expressions. This can be as basic as supplying a select
helper like starts_with(), or, providing a more complex incantation like
where(~ is.numeric(.x) && max(.x, na.rm = TRUE) > 1E6)
which targets numeric columns that have a maximum value greater than
1,000,000 (excluding any NAs from consideration).
By default all columns and rows are selected (with the everything()
defaults). Cell values that are incompatible with a given formatting function
will be skipped over, like character values and numeric fmt_*()
functions. So it's safe to select all columns with a particular formatting
function (only those values that can be formatted will be formatted), but,
you may not want that. One strategy is to format the bulk of cell values with
one formatting function and then constrain the columns for later passes with
other types of formatting (the last formatting done to a cell is what you get
in the final output).
Once the columns are targeted, we may also target the rows within those
columns. This can be done in a variety of ways. If a stub is present, then we
potentially have row identifiers. Those can be used much like column names in
the columns-targeting scenario. We can use simpler tidyselect-style
expressions (the select helpers should work well here) and we can use quoted
row identifiers in c(). It's also possible to use row indices (e.g.,
c(3, 5, 6)) though these index values must correspond to the row numbers of
the input data (the indices won't necessarily match those of rearranged rows
if row groups are present). One more type of expression is possible, an
expression that takes column values (can involve any of the available columns
in the table) and returns a logical vector. This is nice if you want to base
formatting on values in the column or another column, or, you'd like to use a
more complex predicate expression.
Compatibility of arguments with the from_column() helper function
from_column() can be used with certain arguments of fmt_date() to obtain
varying parameter values from a specified column within the table. This means
that each row could be formatted a little bit differently. These arguments
provide support for from_column():
-
date_style
-
pattern
-
locale
Please note that for each of the aforementioned arguments, a from_column()
call needs to reference a column that has data of the correct type (this is
different for each argument). Additional columns for parameter values can be
generated with cols_add() (if not already present). Columns that contain
parameter data can also be hidden from final display with cols_hide().
Finally, there is no limitation to how many arguments the from_column()
helper is applied so long as the arguments belong to this closed set.
Formatting with the date_style argument
We need to supply a preset date style to the date_style argument. The date
styles are numerous and can handle localization to any supported locale. A
large segment of date styles are termed flexible date formats and this means
that their output will adapt to any locale provided. That feature makes the
flexible date formats a better option for locales other than "en" (the
default locale).
The following table provides a listing of all date styles and their output
values (corresponding to an input date of 2000-02-29).
Date Style Output Notes
1 "iso" "2000-02-29" ISO 8601
2 "wday_month_day_year" "Tuesday, February 29, 2000"
3 "wd_m_day_year" "Tue, Feb 29, 2000"
4 "wday_day_month_year" "Tuesday 29 February 2000"
5 "month_day_year" "February 29, 2000"
6 "m_day_year" "Feb 29, 2000"
7 "day_m_year" "29 Feb 2000"
8 "day_month_year" "29 February 2000"
9 "day_month" "29 February"
10 "day_m" "29 Feb"
11 "year" "2000"
12 "month" "February"
13 "day" "29"
14 "year.mn.day" "2000/02/29"
15 "y.mn.day" "00/02/29"
16 "year_week" "2000-W09"
17 "year_quarter" "2000-Q1"
18 "yMd" "2/29/2000" flexible
19 "yMEd" "Tue, 2/29/2000" flexible
20 "yMMM" "Feb 2000" flexible
21 "yMMMM" "February 2000" flexible
22 "yMMMd" "Feb 29, 2000" flexible
23 "yMMMEd" "Tue, Feb 29, 2000" flexible
24 "GyMd" "2/29/2000 A" flexible
25 "GyMMMd" "Feb 29, 2000 AD" flexible
26 "GyMMMEd" "Tue, Feb 29, 2000 AD" flexible
27 "yM" "2/2000" flexible
28 "Md" "2/29" flexible
29 "MEd" "Tue, 2/29" flexible
30 "MMMd" "Feb 29" flexible
31 "MMMEd" "Tue, Feb 29" flexible
32 "MMMMd" "February 29" flexible
33 "GyMMM" "Feb 2000 AD" flexible
34 "yQQQ" "Q1 2000" flexible
35 "yQQQQ" "1st quarter 2000" flexible
36 "Gy" "2000 AD" flexible
37 "y" "2000" flexible
38 "M" "2" flexible
39 "MMM" "Feb" flexible
40 "d" "29" flexible
41 "Ed" "29 Tue" flexible
We can call info_date_style() in the console to view a similar table
of date styles with example output.
Adapting output to a specific locale
This formatting function can adapt outputs according to a provided locale
value. Examples include "en" for English (United States) and "fr" for
French (France). Note that a locale value provided here will override any
global locale setting performed in gt()'s own locale argument (it is
settable there as a value received by all other functions that have a
locale argument). As a useful reference on which locales are supported, we
can call info_locales() to view an info table.
Examples
Let's use the exibble dataset to create a simple, two-column gt table
(keeping only the date and time columns). With fmt_date(), we'll format
the date column to display dates formatted with the "month_day_year"
date style.
exibble |>
dplyr::select(date, time) |>
gt() |>
fmt_date(
columns = date,
date_style = "month_day_year"
)
Again using the exibble dataset, let's format the date column to have
mixed date formats, where dates after April 1st will be different than the
others because of the expressions used in the rows argument. This will
involve two calls of fmt_date() with different statements provided for
rows. In the first call (dates after the 1st of April) the date style
"m_day_year" is used; for the second call, "day_m_year" is the named
date style supplied to date_style.
exibble |>
dplyr::select(date, time) |>
gt() |>
fmt_date(
columns = date,
rows = as.Date(date) > as.Date("2015-04-01"),
date_style = "m_day_year"
) |>
fmt_date(
columns = date,
rows = as.Date(date) <= as.Date("2015-04-01"),
date_style = "day_m_year"
)
Use the exibble dataset to create a single-column gt table (with only
the date column). Format the date values using the "yMMMEd" date style
(which is one of the 'flexible' styles). Also, we'll set the locale to "nl"
to get the dates in Dutch.
exibble |>
dplyr::select(date) |>
gt() |>
fmt_date(
date_style = "yMMMEd",
locale = "nl"
)
Function ID
3-13
Function Introduced
v0.2.0.5 (March 31, 2020)
See Also
The vector-formatting version of this function: vec_fmt_date().
Other data formatting functions:
data_color(),
fmt(),
fmt_auto(),
fmt_bins(),
fmt_bytes(),
fmt_chem(),
fmt_country(),
fmt_currency(),
fmt_datetime(),
fmt_duration(),
fmt_email(),
fmt_engineering(),
fmt_flag(),
fmt_fraction(),
fmt_icon(),
fmt_image(),
fmt_index(),
fmt_integer(),
fmt_markdown(),
fmt_number(),
fmt_partsper(),
fmt_passthrough(),
fmt_percent(),
fmt_roman(),
fmt_scientific(),
fmt_spelled_num(),
fmt_tf(),
fmt_time(),
fmt_units(),
fmt_url(),
sub_large_vals(),
sub_missing(),
sub_small_vals(),
sub_values(),
sub_zero()
gt documentation built on Sept. 11, 2024, 5:15 p.m.
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| fmt_date | R Documentation |
Format values as dates
Description
Format input values to time values using one of 41 preset date styles. Input
can be in the form of POSIXt (i.e., datetimes), the Date type, or
character (must be in the ISO 8601 form of YYYY-MM-DD HH:MM:SS or
YYYY-MM-DD).
Usage
fmt_date(
data,
columns = everything(),
rows = everything(),
date_style = "iso",
pattern = "{x}",
locale = NULL
)
Arguments
data |
The gt table data object
This is the gt table object that is commonly created through use of the
|
columns |
Columns to target
Can either be a series of column names provided in |
rows |
Rows to target
In conjunction with |
date_style |
Predefined style for dates
The date style to use. By default this is the short name |
pattern |
Specification of the formatting pattern
A formatting pattern that allows for decoration of the formatted value. The
formatted value is represented by the |
locale |
Locale identifier
An optional locale identifier that can be used for formatting values
according the locale's rules. Examples include |
Value
An object of class gt_tbl.
Compatibility of formatting function with data values
fmt_date() is compatible with body cells that are of the "Date",
"POSIXt" or "character" types. Any other types of body cells are ignored
during formatting. This is to say that cells of incompatible data types may
be targeted, but there will be no attempt to format them.
Targeting cells with columns and rows
Targeting of values is done through columns and additionally by rows (if
nothing is provided for rows then entire columns are selected). The
columns argument allows us to target a subset of cells contained in the
resolved columns. We say resolved because aside from declaring column names
in c() (with bare column names or names in quotes) we can use
tidyselect-style expressions. This can be as basic as supplying a select
helper like starts_with(), or, providing a more complex incantation like
where(~ is.numeric(.x) && max(.x, na.rm = TRUE) > 1E6)
which targets numeric columns that have a maximum value greater than
1,000,000 (excluding any NAs from consideration).
By default all columns and rows are selected (with the everything()
defaults). Cell values that are incompatible with a given formatting function
will be skipped over, like character values and numeric fmt_*()
functions. So it's safe to select all columns with a particular formatting
function (only those values that can be formatted will be formatted), but,
you may not want that. One strategy is to format the bulk of cell values with
one formatting function and then constrain the columns for later passes with
other types of formatting (the last formatting done to a cell is what you get
in the final output).
Once the columns are targeted, we may also target the rows within those
columns. This can be done in a variety of ways. If a stub is present, then we
potentially have row identifiers. Those can be used much like column names in
the columns-targeting scenario. We can use simpler tidyselect-style
expressions (the select helpers should work well here) and we can use quoted
row identifiers in c(). It's also possible to use row indices (e.g.,
c(3, 5, 6)) though these index values must correspond to the row numbers of
the input data (the indices won't necessarily match those of rearranged rows
if row groups are present). One more type of expression is possible, an
expression that takes column values (can involve any of the available columns
in the table) and returns a logical vector. This is nice if you want to base
formatting on values in the column or another column, or, you'd like to use a
more complex predicate expression.
Compatibility of arguments with the from_column() helper function
from_column() can be used with certain arguments of fmt_date() to obtain
varying parameter values from a specified column within the table. This means
that each row could be formatted a little bit differently. These arguments
provide support for from_column():
-
date_style -
pattern -
locale
Please note that for each of the aforementioned arguments, a from_column()
call needs to reference a column that has data of the correct type (this is
different for each argument). Additional columns for parameter values can be
generated with cols_add() (if not already present). Columns that contain
parameter data can also be hidden from final display with cols_hide().
Finally, there is no limitation to how many arguments the from_column()
helper is applied so long as the arguments belong to this closed set.
Formatting with the date_style argument
We need to supply a preset date style to the date_style argument. The date
styles are numerous and can handle localization to any supported locale. A
large segment of date styles are termed flexible date formats and this means
that their output will adapt to any locale provided. That feature makes the
flexible date formats a better option for locales other than "en" (the
default locale).
The following table provides a listing of all date styles and their output
values (corresponding to an input date of 2000-02-29).
| Date Style | Output | Notes | |
| 1 | "iso" | "2000-02-29" | ISO 8601 |
| 2 | "wday_month_day_year" | "Tuesday, February 29, 2000" | |
| 3 | "wd_m_day_year" | "Tue, Feb 29, 2000" | |
| 4 | "wday_day_month_year" | "Tuesday 29 February 2000" | |
| 5 | "month_day_year" | "February 29, 2000" | |
| 6 | "m_day_year" | "Feb 29, 2000" | |
| 7 | "day_m_year" | "29 Feb 2000" | |
| 8 | "day_month_year" | "29 February 2000" | |
| 9 | "day_month" | "29 February" | |
| 10 | "day_m" | "29 Feb" | |
| 11 | "year" | "2000" | |
| 12 | "month" | "February" | |
| 13 | "day" | "29" | |
| 14 | "year.mn.day" | "2000/02/29" | |
| 15 | "y.mn.day" | "00/02/29" | |
| 16 | "year_week" | "2000-W09" | |
| 17 | "year_quarter" | "2000-Q1" | |
| 18 | "yMd" | "2/29/2000" | flexible |
| 19 | "yMEd" | "Tue, 2/29/2000" | flexible |
| 20 | "yMMM" | "Feb 2000" | flexible |
| 21 | "yMMMM" | "February 2000" | flexible |
| 22 | "yMMMd" | "Feb 29, 2000" | flexible |
| 23 | "yMMMEd" | "Tue, Feb 29, 2000" | flexible |
| 24 | "GyMd" | "2/29/2000 A" | flexible |
| 25 | "GyMMMd" | "Feb 29, 2000 AD" | flexible |
| 26 | "GyMMMEd" | "Tue, Feb 29, 2000 AD" | flexible |
| 27 | "yM" | "2/2000" | flexible |
| 28 | "Md" | "2/29" | flexible |
| 29 | "MEd" | "Tue, 2/29" | flexible |
| 30 | "MMMd" | "Feb 29" | flexible |
| 31 | "MMMEd" | "Tue, Feb 29" | flexible |
| 32 | "MMMMd" | "February 29" | flexible |
| 33 | "GyMMM" | "Feb 2000 AD" | flexible |
| 34 | "yQQQ" | "Q1 2000" | flexible |
| 35 | "yQQQQ" | "1st quarter 2000" | flexible |
| 36 | "Gy" | "2000 AD" | flexible |
| 37 | "y" | "2000" | flexible |
| 38 | "M" | "2" | flexible |
| 39 | "MMM" | "Feb" | flexible |
| 40 | "d" | "29" | flexible |
| 41 | "Ed" | "29 Tue" | flexible |
We can call info_date_style() in the console to view a similar table
of date styles with example output.
Adapting output to a specific locale
This formatting function can adapt outputs according to a provided locale
value. Examples include "en" for English (United States) and "fr" for
French (France). Note that a locale value provided here will override any
global locale setting performed in gt()'s own locale argument (it is
settable there as a value received by all other functions that have a
locale argument). As a useful reference on which locales are supported, we
can call info_locales() to view an info table.
Examples
Let's use the exibble dataset to create a simple, two-column gt table
(keeping only the date and time columns). With fmt_date(), we'll format
the date column to display dates formatted with the "month_day_year"
date style.
exibble |>
dplyr::select(date, time) |>
gt() |>
fmt_date(
columns = date,
date_style = "month_day_year"
)
Again using the exibble dataset, let's format the date column to have
mixed date formats, where dates after April 1st will be different than the
others because of the expressions used in the rows argument. This will
involve two calls of fmt_date() with different statements provided for
rows. In the first call (dates after the 1st of April) the date style
"m_day_year" is used; for the second call, "day_m_year" is the named
date style supplied to date_style.
exibble |>
dplyr::select(date, time) |>
gt() |>
fmt_date(
columns = date,
rows = as.Date(date) > as.Date("2015-04-01"),
date_style = "m_day_year"
) |>
fmt_date(
columns = date,
rows = as.Date(date) <= as.Date("2015-04-01"),
date_style = "day_m_year"
)
Use the exibble dataset to create a single-column gt table (with only
the date column). Format the date values using the "yMMMEd" date style
(which is one of the 'flexible' styles). Also, we'll set the locale to "nl"
to get the dates in Dutch.
exibble |>
dplyr::select(date) |>
gt() |>
fmt_date(
date_style = "yMMMEd",
locale = "nl"
)
Function ID
3-13
Function Introduced
v0.2.0.5 (March 31, 2020)
See Also
The vector-formatting version of this function: vec_fmt_date().
Other data formatting functions:
data_color(),
fmt(),
fmt_auto(),
fmt_bins(),
fmt_bytes(),
fmt_chem(),
fmt_country(),
fmt_currency(),
fmt_datetime(),
fmt_duration(),
fmt_email(),
fmt_engineering(),
fmt_flag(),
fmt_fraction(),
fmt_icon(),
fmt_image(),
fmt_index(),
fmt_integer(),
fmt_markdown(),
fmt_number(),
fmt_partsper(),
fmt_passthrough(),
fmt_percent(),
fmt_roman(),
fmt_scientific(),
fmt_spelled_num(),
fmt_tf(),
fmt_time(),
fmt_units(),
fmt_url(),
sub_large_vals(),
sub_missing(),
sub_small_vals(),
sub_values(),
sub_zero()
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Note that we can't provide technical support on individual packages. You should contact the package authors for that.
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