| seq.POSIXt {base} | R Documentation |
The method for seq for data-time classes.
## S3 method for class 'POSIXt'
seq(from, to, by, length.out=NULL, along.with=NULL, ...)
from |
starting date. Required |
to |
end date. Optional. If supplied must be after |
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 seconds.
A object of class difftime
A character string, containing one of "sec",
"min", "hour", "day", "DSTday",
"week", "month" or "year". This can optionally be
preceded by an integer and a space, or followed by "s".
The difference between "day" and "DSTday" is that the
former ignores changes to/from daylight savings time and the latter takes
the same clock time each day. ("week" ignores DST, but
"7 DSTdays") can be used as an alternative. "month" and
"year" allow for DST as from R 1.5.0.)
A vector of class "POSIXct".
DateTimeClasses
## first days of years
seq(ISOdate(1910,1,1), ISOdate(1999,1,1), "years")
## by month
seq(ISOdate(2000,1,1), by="month", length=12)
## quarters
seq(ISOdate(1990,1,1), ISOdate(2000,1,1), by="3 months")
## days vs DSTdays
seq(ISOdate(2000,3,20), by="day", length = 10)
seq(ISOdate(2000,3,20), by="DSTday", length = 10)
seq(ISOdate(2000,3,20), by="7 DSTdays", length = 4)