stringi (version 1.3.1)

stri_datetime_add: Date and Time Arithmetic

Description

Modifies a date-time object by adding a specific amount of time units.

Usage

stri_datetime_add(time, value = 1L, units = "seconds", tz = NULL,
  locale = NULL)
stri_datetime_add(time, units = "seconds", tz = NULL,
  locale = NULL) <- value

Arguments

time

an object of class POSIXct or an object coercible to

value

integer vector; signed number of units to add to time

units

single string; one of "years", "months", "weeks", "days", "hours", "minutes", "seconds", or "milliseconds"

tz

NULL or "" for the default time zone or a single string with a timezone identifier,

locale

NULL or "" for default locale, or a single string with locale identifier; a non-Gregorian calendar may be specified by setting the @calendar=name keyword

Value

Both functions return an object of class POSIXct.

The replacement version of stri_datetime_add modifies the state of the time object.

Details

Vectorized over time and value.

Note that, e.g., January, 31 + 1 month = February, 28 or 29.

References

Calendar Classes - ICU User Guide, http://userguide.icu-project.org/datetime/calendar

See Also

Other datetime: stri_datetime_create, stri_datetime_fields, stri_datetime_format, stri_datetime_fstr, stri_datetime_now, stri_datetime_symbols, stri_timezone_get, stri_timezone_info, stri_timezone_list

Examples

# NOT RUN {
x <- stri_datetime_now()
stri_datetime_add(x, units="months") <- 2
print(x)
stri_datetime_add(x, -2, units="months")
stri_datetime_add(stri_datetime_create(2014, 4, 20), 1, units="years")
stri_datetime_add(stri_datetime_create(2014, 4, 20), 1, units="years", locale="@calendar=hebrew")

stri_datetime_add(stri_datetime_create(2016, 1, 31), 1, units="months")

# }