calculate ages in r

gistfile1.txt

# Calculate ages using lubridate


#option 1
library(lubridate)
library(dplyr)

today()  #get today's date

today() - as.Date("1992-05-23") #calculate difference in days between two dates

as.period(today() - as.Date("1992-05-23"), units=c("year")) #convert to years

as.period(today() - as.Date("1992-05-23"), units=c("year")) %>% .$year #extract year



# option 2 - much better...

# This is an excellent customized function written by this person:
# http://stackoverflow.com/questions/14454476/get-the-difference-between-dates-in-terms-of-weeks-months-quarters-and-years

age <- function(dob, age.day = today(), units = "years", floor = TRUE) {
  calc.age = new_interval(dob, age.day) / duration(num = 1, units = units)
  if (floor) return(as.integer(floor(calc.age)))
  return(calc.age)
}

age(as.Date('1977-03-28'))  #calculates age of anyone

I think option2 might be a bit behind on birthdays .... but option1 seems accurate always.