| seq.POSIXt {base} | R Documentation |
The method for seq for date-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. |
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.
difftime
"sec",
"min", "hour", "day", "DSTday",
"week", "month" or "year". This can optionally be
preceded by a (positive or negative) 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.)
The timezone of the result is taken from from: remember than
GMT does not have daylight savings time.
A vector of class "POSIXct".
## 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: use c() to lose the timezone. seq(c(ISOdate(2000,3,20)), by = "day", length = 10) seq(c(ISOdate(2000,3,20)), by = "DSTday", length = 10) seq(c(ISOdate(2000,3,20)), by = "7 DSTdays", length = 4)