date_time_build()
builds a POSIXct from it's individual components.
To build a POSIXct, it is required that you specify the zone
.
date_time_build(
year,
month = 1L,
day = 1L,
hour = 0L,
minute = 0L,
second = 0L,
...,
zone,
invalid = NULL,
nonexistent = NULL,
ambiguous = NULL
)
A POSIXct.
[integer]
The year. Values [-32767, 32767]
are generally allowed.
[integer]
The month. Values [1, 12]
are allowed.
[integer / "last"]
The day of the month. Values [1, 31]
are allowed.
If "last"
, then the last day of the month is returned.
[integer]
The hour. Values [0, 23]
are allowed.
[integer]
The minute. Values [0, 59]
are allowed.
[integer]
The second. Values [0, 59]
are allowed.
These dots are for future extensions and must be empty.
[character(1)]
A valid time zone name.
This argument is required, and must be specified by name.
[character(1) / NULL]
One of the following invalid date resolution strategies:
"previous"
: The previous valid instant in time.
"previous-day"
: The previous valid day in time, keeping the time of
day.
"next"
: The next valid instant in time.
"next-day"
: The next valid day in time, keeping the time of day.
"overflow"
: Overflow by the number of days that the input is invalid
by. Time of day is dropped.
"overflow-day"
: Overflow by the number of days that the input is
invalid by. Time of day is kept.
"NA"
: Replace invalid dates with NA
.
"error"
: Error on invalid dates.
Using either "previous"
or "next"
is generally recommended, as these
two strategies maintain the relative ordering between elements of the
input.
If NULL
, defaults to "error"
.
If getOption("clock.strict")
is TRUE
, invalid
must be supplied and
cannot be NULL
. This is a convenient way to make production code robust
to invalid dates.
[character / NULL]
One of the following nonexistent time resolution strategies, allowed to be either length 1, or the same length as the input:
"roll-forward"
: The next valid instant in time.
"roll-backward"
: The previous valid instant in time.
"shift-forward"
: Shift the nonexistent time forward by the size of
the daylight saving time gap.
"shift-backward
: Shift the nonexistent time backward by the size of
the daylight saving time gap.
"NA"
: Replace nonexistent times with NA
.
"error"
: Error on nonexistent times.
Using either "roll-forward"
or "roll-backward"
is generally
recommended over shifting, as these two strategies maintain the
relative ordering between elements of the input.
If NULL
, defaults to "error"
.
If getOption("clock.strict")
is TRUE
, nonexistent
must be supplied
and cannot be NULL
. This is a convenient way to make production code
robust to nonexistent times.
[character / zoned_time / POSIXct / list(2) / NULL]
One of the following ambiguous time resolution strategies, allowed to be either length 1, or the same length as the input:
"earliest"
: Of the two possible times, choose the earliest one.
"latest"
: Of the two possible times, choose the latest one.
"NA"
: Replace ambiguous times with NA
.
"error"
: Error on ambiguous times.
Alternatively, ambiguous
is allowed to be a zoned_time (or POSIXct) that
is either length 1, or the same length as the input. If an ambiguous time
is encountered, the zoned_time is consulted. If the zoned_time corresponds
to a naive_time that is also ambiguous and uses the same daylight saving
time transition point as the original ambiguous time, then the offset of
the zoned_time is used to resolve the ambiguity. If the ambiguity cannot be
resolved by consulting the zoned_time, then this method falls back to
NULL
.
Finally, ambiguous
is allowed to be a list of size 2, where the first
element of the list is a zoned_time (as described above), and the second
element of the list is an ambiguous time resolution strategy to use when
the ambiguous time cannot be resolved by consulting the zoned_time.
Specifying a zoned_time on its own is identical to list(<zoned_time>, NULL)
.
If NULL
, defaults to "error"
.
If getOption("clock.strict")
is TRUE
, ambiguous
must be supplied and
cannot be NULL
. Additionally, ambiguous
cannot be specified as a
zoned_time on its own, as this implies NULL
for ambiguous times that the
zoned_time cannot resolve. Instead, it must be specified as a list
alongside an ambiguous time resolution strategy as described above. This is
a convenient way to make production code robust to ambiguous times.
Components are recycled against each other using tidyverse recycling rules.
# The zone argument is required!
# clock always requires you to be explicit about your choice of `zone`.
try(date_time_build(2020))
date_time_build(2020, zone = "America/New_York")
# Nonexistent time due to daylight saving time gap from 01:59:59 -> 03:00:00
try(date_time_build(1970, 4, 26, 1:12, 30, zone = "America/New_York"))
# Resolve with a nonexistent time resolution strategy
date_time_build(
1970, 4, 26, 1:12, 30,
zone = "America/New_York",
nonexistent = "roll-forward"
)
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