Hi Thomas, Be aware that if you are attempting to calculate "birthday age", it is probably better to do it like this:
bdage<-function(dob,now) { dobbits<-as.numeric(unlist(strsplit(dob,"/"))) nowbits<-as.numeric(unlist(strsplit(now,"/"))) return(nowbits[3]-dobbits[3]- (nowbits[2]<dobbits[2] || (nowbits[2]==dobbits[2] && nowbits[1]<dobbits[1]))) } bdage("20/09/1945","5/8/2016") You can also do this with date objects, just add the appropriate format arguments. Jim Jim On Fri, Aug 5, 2016 at 6:35 AM, William Dunlap via R-help <r-help@r-project.org> wrote: > difftime objects do not accept 'years' as a value for 'units', so you have > to change it to numeric. > > as.numeric(age_days, units="days") / 365.242 > > The units="days" is not needed since you specified it in the call > to difftime, but it needs to be in one of those places. > > Bill Dunlap > TIBCO Software > wdunlap tibco.com > > On Thu, Aug 4, 2016 at 11:05 AM, Thomas Subia via R-help < > r-help@r-project.org> wrote: > >> Colleagues, >> >> age_days <- difftime(Date,DOM,units="days") >> date_vals$age_yrs <- age_days/365.242 >> >> I'm trying to calculate the number of years between DOM and Date. >> The output reads >> >> DOM Date age_yrs >> 1 2005-04-04 2015-05-13 10.10563 days >> >> How does one not output days? >> >> ______________________________________________ >> R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see >> 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]] > > ______________________________________________ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > 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@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.