Dear All, I wonder how to compute the age from the date of birth and the date
of examination. Suppose that have the following data:
df <- as.data.frame(rbind(c(1,"10/08/1950","15/03/1998"),
c(1,"10/08/1950","20/07/1998"), c(1,"10/08/1950","23/10/1998")))
names(df) <- c("ID", "date_birth", "date_exam")
where:
date_birth: is the date of birth
date_exam: date of examination
I used the following program to compute the value of the age :
difftime(strptime(as.character(df$date_exam), '%d/%m/%Y'),
strptime(as.character(df$date_birth), '%d/%m/%Y'))/365.25
which gives me as an output:
> Time differences of 47.59491, 47.94251, 48.20260 days
theses values are actually the 3 ages (but
My questions are:
1- Why in the output it says "days" instead of "years")
2- How can I obtain the output as a numeric vector, without the statement
"Time difference of ....". This is in order to use it in my calculations.
3- Is there a way quicker and less redondant to compute the age form the
date_birth and date_exam?
Thanks a lot,
Bernard,
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