leap years in temporal series command ts
On Wed, Feb 16, 2011 at 6:51 AM, Peter Zorglub <peter.zorglub at gmail.com> wrote:
Hi R community! I'd like to create a temporal series with ts command for the interval 1st January 2002 - 31 December 2008. I have daily values, so this is a 2557 days temporal series. I'm using this command : ? ?ts(observations, start=2002, end=2009, freq=365) However, I don't get the correct temporal series since both frequency (365 OR 366 for leap years) and deltat (1/365 OR 1/366) are varying with the year considered. So, is there a specific way to deal with leap years in the ts command or have I to use another package?
You could do this with an implied frequency of 1
tt <- ts(1:10, start=as.Date("2000-01-01"))
which would represent the times as days since the Epoch. You can
recover the Date class dates with:
as.Date(tt, origin = "1970-01-01")
You might be better off using zoo or xts. e.g.
library(zoo)
z <- zooreg(1:10, start = as.Date("2000-01-01"))
Its also possible to move back and forth:
as.ts(z)
as.zoo(tt)
aggregate(as.zoo(tt), identity, as.Date)
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