seq.dates(from, to, by = "days", length.out, k.by = 1)
dates
object,
an integer representing a Julian date, or a character string of the
form
"mm/dd/yy"
, for example
"05/23/91"
.
from
. One of
to
or
from
or both
needs to be specified.
"days"
,
"weekdays"
,
"weeks"
,
"months"
,
"quarters"
or
"years"
giving the desired time units of
the intervals between dates. Default is one day.
by
argument.
This is ignored if
by
is numeric or
by="weekdays"
.
from
and
to
separated by
k.by
time units as defined by the argument
by
.
The origin of the sequence will be the same as
origin(from)
or
origin(to)
.
by="weekdays"
, all the weekdays between
from
and
to
are generated.
At least one of
from
or
to
is required plus
length.out
, the desired
length of the resulting sequence; or both
from
and
to
in which case
length.out
gets ignored if supplied.
For
by="weekdays"
, if given
from
(or
to
) is a weekend, the next
Monday (or the last Friday) is used as the start (or end).
seq.dates("01/01/92", "12/31/92", by="months") # Produces: # [1] 01/01/92 02/01/92 03/01/92 04/01/92 05/01/92 06/01/92 # [7] 07/01/92 08/01/92 09/01/92 10/01/92 11/01/92 12/01/92 quarters1 <- seq.dates("01/01/92", "12/31/92", by="quarters") quarters2 <- seq.dates("01/01/92", "12/31/92",by="months",k=3) all(quarters1 == quarters2) end.of.the.month <- seq.dates("02/29/92", by="months", length=15) end.of.the.month # Produces: # [1] 02/29/92 03/31/92 04/30/92 05/31/92 06/30/92 07/31/92 # [7] 08/31/92 09/30/92 10/31/92 11/30/92 12/31/92 01/31/93 # [13] 02/28/93 03/31/93 04/30/93