Hi folks, I have a small, maybe newbie, question concerning date operations. The follwing snippet date1 = "2005-11-20"; date2 = "2005-11-17"; difftime(date1, date2) results in "Time difference of 3 days". How can I extract just the numerical value 3? As a workaround I apply mean() on the result which gives me just a numerical value. Thanks a lot, Christian
Christian Neumann wrote:> Hi folks, > > I have a small, maybe newbie, question concerning date operations. > The follwing snippet > > date1 = "2005-11-20"; > date2 = "2005-11-17"; > difftime(date1, date2) > > results in "Time difference of 3 days". How can I extract just the > numerical value 3? > As a workaround I apply mean() on the result which gives me just a > numerical value.If you want to get one thing _as_ another the R-ish solution is nearly always to do as.another(oneThing). You want it numeric? You got it! > date1 = "2005-11-20"; > date2 = "2005-11-17"; > difftime(date1, date2) Time difference of 3 days > as.numeric(difftime(date1, date2)) [1] 3 Barry
This was just discussed two days ago: https://www.stat.math.ethz.ch/pipermail/r-help/2006-January/084453.html On 1/13/06, Christian Neumann <christian.neumann at ai.wu-wien.ac.at> wrote:> Hi folks, > > I have a small, maybe newbie, question concerning date operations. > The follwing snippet > > date1 = "2005-11-20"; > date2 = "2005-11-17"; > difftime(date1, date2) > > results in "Time difference of 3 days". How can I extract just the > numerical value 3? > As a workaround I apply mean() on the result which gives me just a > numerical value. > > Thanks a lot, > > Christian > > ______________________________________________ > R-help at stat.math.ethz.ch mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html >
just try
as.numeric(difftime(date1, date2))
Best,
Dimitris
----
Dimitris Rizopoulos
Ph.D. Student
Biostatistical Centre
School of Public Health
Catholic University of Leuven
Address: Kapucijnenvoer 35, Leuven, Belgium
Tel: +32/(0)16/336899
Fax: +32/(0)16/337015
Web: http://www.med.kuleuven.be/biostat/
http://www.student.kuleuven.be/~m0390867/dimitris.htm
----- Original Message -----
From: "Christian Neumann" <christian.neumann at
ai.wu-wien.ac.at>
To: <r-help at stat.math.ethz.ch>
Sent: Friday, January 13, 2006 2:05 PM
Subject: [R] Getting the numeric value of difftime
> Hi folks,
>
> I have a small, maybe newbie, question concerning date operations.
> The follwing snippet
>
> date1 = "2005-11-20";
> date2 = "2005-11-17";
> difftime(date1, date2)
>
> results in "Time difference of 3 days". How can I extract just
the
> numerical value 3?
> As a workaround I apply mean() on the result which gives me just a
> numerical value.
>
> Thanks a lot,
>
> Christian
>
> ______________________________________________
> R-help at stat.math.ethz.ch mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide!
> http://www.R-project.org/posting-guide.html
>
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