powered by
Date-time must be a POSIXct, POSIXlt, Date, Period or any other object convertible to POSIXlt.
isoyear() returns years according to the ISO 8601 week calendar.
isoyear()
epiyear() returns years according to the epidemiological week calendars.
epiyear()
year(x)year(x) <- valueisoyear(x)epiyear(x)
year(x) <- value
isoyear(x)
epiyear(x)
the years element of x as a decimal number
a date-time object
a numeric object
year does not yet support years before 0 C.E.
https://en.wikipedia.org/wiki/ISO_week_date
x <- ymd("2012-03-26") year(x) year(x) <- 2001 year(x) > 1995
Run the code above in your browser using DataLab