get_aweek: Convert week numbers to dates or aweek objects

In aweek: Convert Dates to Arbitrary Week Definitions

Convert week numbers to dates or aweek objects

Description

These are vectorized functions that take integer vectors and return Date or an aweek objects, making it easier to convert bare weeks to dates.

Usage

get_aweek(
  week = 1L,
  year = format(Sys.Date(), "%Y"),
  day = 1L,
  start = week_start,
  week_start = get_week_start(),
  ...
)

get_date(
  week = 1L,
  year = format(Sys.Date(), "%Y"),
  day = 1L,
  start = get_week_start()
)

Arguments

week	an integer vector, defaults to 1, representing the first week of the year.
year	an integer vector, defaults to the current year
day	an integer vector, defaults to 1, representing the first day of the first week of the year.
start	an integer (or character) vector of days that the weeks start on for each corresponding week. Defaults to the value of get_week_start(). Note that these will not determine the final week.
week_start	a number indicating the start of the week based on the ISO 8601 standard from 1 to 7 where 1 = Monday OR an abbreviation of the weekdate in an English or current locale. Note: using a non-English locale may render your code non-portable. Defaults to the value of get_week_start()
...	parameters passed on to date2week()

Value

• get_aweek(): an aweek object

• get_date(): a Date object

Note

Any missing weeks, years, or start elements will result in a missing element in the resulting vector. Any missing days will revert to the first day of the week.

See Also

as.aweek() date2week() week2date()

Examples

# The default results in the first week of the year using the default
# default week_start (from get_week_start())

get_aweek()
get_date() # this is equivalent to as.Date(get_week()), but faster 

# Some years, like 2015, have 53 weeks

get_aweek(53, 2015)

# If you specify 53 weeks for a year that doesn't have 53 weeks, aweek will
# happily correct it for you

get_aweek(53, 2014) # this will be 2015-W01-1

# you can use this to quickly make a week without worrying about formatting
# here, you can define an observation interval of 20 weeks

obs_start <- get_date(week = 10, year = 2018)
obs_end   <- get_date(week = 29, year = 2018, day = 7)
c(obs_start, obs_end)

# If you have a data frame of weeks, you can use it to convert easily

mat <- matrix(c(
  2019, 11, 1, 7, # 2019-03-10
  2019, 11, 2, 7,
  2019, 11, 3, 7,
  2019, 11, 4, 7,
  2019, 11, 5, 7,
  2019, 11, 6, 7,
  2019, 11, 7, 7
), ncol = 4, byrow = TRUE)

colnames(mat) <- c("year", "week", "day", "start")
m <- as.data.frame(mat)
m
sun <- with(m, get_date(week, year, day, start))
sun
as.aweek(sun) # convert to aweek starting on the global week_start 
as.aweek(sun, week_start = "Sunday") # convert to aweek starting on Sunday

# You can also change starts
mon <- with(m, get_aweek(week, year, day, "Monday", week_start = "Monday"))
mon
as.Date(mon)

# If you use multiple week starts, it will convert to date and then to
# the correct week, so it won't appear to match up with the original
# data frame.

sft <- with(m, get_aweek(week, year, day, 7:1, week_start = "Sunday"))
sft
as.Date(sft)

aweek documentation built on Oct. 6, 2022, 9:07 a.m.