| as.ym {DescTools} | R Documentation |
A Class for Dealing with the Yearmonth Format
Description
The representation of year and month information in YYYYYMM format as an integer is often handy and a useful and efficient data structure. Adding a number of months to such a date is not quite catchy, however, since the date structure is to be retained. For example, 201201 - 2 [months] is expected to result in 201111 instead of 201199. AddMonthsYM does this job.
Usage
as.ym(x)
## S3 method for class 'ym'
as.Date(x, d = 1, ...)
## S3 method for class 'ym'
AddMonths(x, n, ...)
Arguments
x |
a vector of integers, representing the dates in the format YYYYMM, to which a number of months has to be added. YYYY must lie in the range of 1000-3000, MM in 1-12. |
d |
the day to be used for converting a yearmonth to a date. Default is 1. |
n |
the number of months to be added. If n is negative the months will be subtracted. |
... |
further arguments (not used here). |
Details
All parameters will be recyled if necessary. The therefore used function mapply will display a warning, if the longer argument is not a multiple of the length of the shorter one.
Value
a vector of class integer with the same dimension as x, containing the transformed dates.
Author(s)
Andri Signorell <andri@signorell.net>, originally based on code by Roland Rapold
See Also
AddMonths; Date functions, like Year, Month, etc.
Examples
Month(as.ym(202408))
Year(as.ym(202408))
Year(as.Date("2024-12-05"))
Year(as.ym(202412))
Month(as.Date("2024-12-05"), fmt = "mm")
Month(as.ym(202412), fmt="mm")
AddMonths(201511, 5)
AddMonths(c(201511, 201302), c(5, 15))
AddMonths(c(201511, 201302), c(5, -4))