| seq.Date {base} | R Documentation |
The method for seq for objects of class class
"Date" representing calendar dates.
## S3 method for class 'Date' seq(from, to, by, length.out = NULL, along.with = NULL, ...)
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. |
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" 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".
A vector of class "Date".
## 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="3 months")
## 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])