difftime in years
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 at 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 at 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?
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______________________________________________ R-help at 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.