Convert Julian date to calendar dates within a data frame

Question

I have a data frame

> df
Age   year  sex
12    80210  F
13     9123  M

I want to convert the year 80210 as 26june1982. How can I do this t

Answer 1

You should substract the origin from the year column.

 as.Date(c(80210,9123)-80210,origin='1982-06-26')
[1] "1982-06-26" "1787-11-08"