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base (version 3.3)

seq.Date: Generate Regular Sequences of Dates

Description

The method for seq for objects of class class "Date" representing calendar dates.

Usage

"seq"(from, to, by, length.out = NULL, along.with = NULL, ...)

Arguments

from
starting date. Required
to
end date. Optional.
by
increment of the sequence. Optional. See ‘Details’.
length.out
integer, optional. Desired length of the sequence.
along.with
take the length from the length of this argument.
...
arguments passed to or from other methods.

Value

A vector of class "Date".

Details

by can be specified in several ways.
  • A number, taken to be in days.
  • A object of class difftime
  • A character string, containing one of "day", "week", "month", "quarter" or "year". This can optionally be preceded by a (positive or negative) integer and a space, or followed by "s".

    See seq.POSIXt for the details of "month".

See Also

Date

Examples

Run this code
## first days of years
seq(as.Date("1910/1/1"), as.Date("1999/1/1"), "years")
## by month
seq(as.Date("2000/1/1"), by = "month", length.out = 12)
## quarters
seq(as.Date("2000/1/1"), as.Date("2003/1/1"), by = "quarter")

## find all 7th of the month between two dates, the last being a 7th.
st <- as.Date("1998-12-17")
en <- as.Date("2000-1-7")
ll <- seq(en, st, by = "-1 month")
rev(ll[ll > st & ll < en])

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