"Date" representing calendar dates.
"summary"(object, digits = 12, ...) It is intended that the date should be an integer, but this is not
enforced in the internal representation. Fractional days will be
ignored when printing. It is possible to produce fractional days via
the mean method or by adding or subtracting (see
Ops.Date).
The print methods respect options("max.print").
Sys.Date for the current date. Ops.Date for operators on "Date" objects.
format.Date for conversion to and from character strings.
axis.Date and
hist.Date for plotting.
weekdays for convenience extraction functions.
seq.Date, cut.Date,
round.Date for utility operations.
DateTimeClasses for date-time classes.