How do I sum 15 years to my dataset?
original dataset
dates val
1 2001-01-12 1.2
2 2001-02-12 1.2
3 2001-03-12 1.2
result
dates val
1 2016-01-12 1.2
2 2016-02-12 1.2
3 2016-03-12 1.2
It depends how your dates are stored, but generally you can just add 365*15 to them. E.g., print(x <- Sys.Date()) print(x + 365*15) So for you, dataset$dates <- dataset$dates + 365*15 Michael On Mon, Dec 12, 2011 at 9:39 PM, Ana <rrasterr at gmail.com> wrote:> How do I sum 15 years to my dataset? > > original dataset > ? ? ? ? dates ? ? ? ?val > 1 ? ?2001-01-12 ? ?1.2 > 2 ? ?2001-02-12 ? ?1.2 > 3 ? ?2001-03-12 ? ?1.2 > > result > ? ? ? ? dates ? ? ? ?val > 1 2016-01-12 1.2 > 2 ? ?2016-02-12 1.2 > 3 ? ?2016-03-12 1.2 > > ______________________________________________ > R-help at r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code.
On 13/12/11 15:39, Ana wrote:> How do I sum 15 years to my dataset?You mean ``How do I ***add*** 15 years ....'' See the thread starting at http://r.789695.n4.nabble.com/Adding-a-year-to-existing-date-tp4078930p4078930.html cheers, Rolf Turner> original dataset > dates val > 1 2001-01-12 1.2 > 2 2001-02-12 1.2 > 3 2001-03-12 1.2 > > result > dates val > 1 2016-01-12 1.2 > 2 2016-02-12 1.2 > 3 2016-03-12 1.2 > > ______________________________________________ > R-help at r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. >
If "adding x years to a date" means "increase the YYYY part of a
date by
x", then it should be easiest to manipulate the character representation
of your date.
dates <-
as.Date(c("2001-01-12","2001-02-12","2001-03-12"))
addYear <- function(d,addyears) {
Y <- as.numeric(strftime(d, "%Y")) + addyears
as.Date(paste(Y, strftime(d,"-%m-%d"), sep = ""))
}
## (There are leapyears with more than 365 days.)
dates + 365*15
addYear(dates,15)
That said, you cannot "go one year ahead" from February 29, unless you
go ahead by 4, 8, 12, ... years (unless the new year is divisible by 100
but not by 400). One possibility would be to leave such dates as Feb 28.
addYear <- function(d,addyears) {
Y <- as.numeric(strftime(d, "%Y")) + addyears
YisLeapyear <- Y%%400==0L | ((Y%%4==0L) & !(Y%%100==0L))
mdpart <- strftime(d,"-%m-%d")
mdpart <- ifelse(mdpart == "-02-29" & YisLeapyear,
mdpart, "-02-28")
as.Date(paste(Y, mdpart, sep = ""))
}
dates <-
as.Date(c("2001-01-12","2001-02-12","2001-03-12",
"1899-02-28","1896-02-29","2000-03-01"))
addYear(dates,4)
addYear(dates,5)
addYear(dates,8)
Regards,
Enrico
Am 13.12.2011 04:17, schrieb R. Michael Weylandt:> It depends how your dates are stored, but generally you can just add
> 365*15 to them. E.g.,
>
> print(x<- Sys.Date())
> print(x + 365*15)
>
> So for you,
>
> dataset$dates<- dataset$dates + 365*15
>
> Michael
>
> On Mon, Dec 12, 2011 at 9:39 PM, Ana<rrasterr at gmail.com> wrote:
>> How do I sum 15 years to my dataset?
>>
>> original dataset
>> dates val
>> 1 2001-01-12 1.2
>> 2 2001-02-12 1.2
>> 3 2001-03-12 1.2
>>
>> result
>> dates val
>> 1 2016-01-12 1.2
>> 2 2016-02-12 1.2
>> 3 2016-03-12 1.2
>>
>> ______________________________________________
>> R-help at r-project.org mailing list
>> https://stat.ethz.ch/mailman/listinfo/r-help
>> PLEASE do read the posting guide
http://www.R-project.org/posting-guide.html
>> and provide commented, minimal, self-contained, reproducible code.
>
> ______________________________________________
> R-help at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>
--
Enrico Schumann
Lucerne, Switzerland
http://nmof.net/
Hi Ana, Check section 4 of http://www.jstatsoft.org/v40/i03/paper for more alternatives. HTH, Jorge.- On Mon, Dec 12, 2011 at 9:39 PM, Ana <> wrote:> How do I sum 15 years to my dataset? > > original dataset > dates val > 1 2001-01-12 1.2 > 2 2001-02-12 1.2 > 3 2001-03-12 1.2 > > result > dates val > 1 2016-01-12 1.2 > 2 2016-02-12 1.2 > 3 2016-03-12 1.2 > > ______________________________________________ > R-help@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide > http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. >[[alternative HTML version deleted]]