Calculating age in R from dob

Question

I am new to R, but I've searched this topic a lot before posting here, because there are plenty of results in google and stackoverflow.

My dataframe has 3041 rows and several columns, DDN is Date of Birth in portuguese.

I've tried all these solutions from other topics, but none os these worked.

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


Age <- as.Date (P4PA$DDN)

P4PA$Idade <- floor(age_calc(P4PA$DDN, units = "years"))

Age <- as.numeric(format(as.Date(Sys.time()),format="%Y"))-as.numeric(format(as.Date(DDN,format="%m/%d/%Y"),format="%Y"))

yourdata$age <- floor(age_calc(yourdata$birthdate, units = "years"))

age = function(from, to) {
from_lt = as.POSIXlt(from)
to_lt = as.POSIXlt(to)

age = to_lt$year - from_lt$year

ifelse(to_lt$mon < from_lt$mon |
     (to_lt$mon == from_lt$mon & to_lt$mday < from_lt$mday),
     age - 1, age)
}

And this: http://blog.jsonbecker.com/2013/06/calculating-age-in-r.html

 head(P4PA) DDN 4/22/1956 12/26/1964 4/16/1963 1/28/1970 7/15/1972 1/18/1956 

class(P4PA$DDN)
"factor"

I need to calculate age from this column with 3041 observations, but I cannot figure out how. I tried to change DDN class to numeric, but a message with Error appears. I really dont know what to do anymore. I thought it would be easy.

Thank you

Answer 1

First, copy and paste the function age_calc from the blog post to which you linked into your R console (or RStudio console) and hit 'Enter' to store it.

The function takes 3 arguments: dob, enddate and units. The dob argument needs to be of class Date . Units can be days, months or years. Assuming that you want years, this should add a column age to your data frame:

P4PA$age <- age_calc(as.Date(P4PA$DDN, "%m/%d/%Y"), units = "years")

P4PA
         DDN age
1  4/22/1956  60
2 12/26/1964  52
3  4/16/1963  53
4  1/28/1970  47
5  7/15/1972  44
6  1/18/1956  61