% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/age.R
\name{age}
\alias{age}
\title{Age in years of individuals}
\usage{
age(x, reference = Sys.Date(), exact = FALSE)
}
\arguments{
\item{x}{date(s), will be coerced with \code{\link{as.POSIXlt}}}

\item{reference}{reference date(s) (defaults to today), will be coerced with \code{\link{as.POSIXlt}} and cannot be lower than \code{x}}

\item{exact}{a logical to indicate whether age calculation should be exact, i.e. with decimals. It divides the number of days of \href{https://en.wikipedia.org/wiki/Year-to-date}{year-to-date} (YTD) of \code{x} by the number of days in a year of \code{reference} (either 365 or 366).}
}
\value{
An integer (no decimals) if \code{exact = FALSE}, a double (with decimals) otherwise
}
\description{
Calculates age in years based on a reference date, which is the sytem date at default.
}
\section{Read more on our website!}{

On our website \url{https://msberends.gitlab.io/AMR} you can find \href{https://msberends.gitlab.io/AMR/articles/AMR.html}{a tutorial} about how to conduct AMR analysis, the \href{https://msberends.gitlab.io/AMR/reference}{complete documentation of all functions} (which reads a lot easier than here in R) and \href{https://msberends.gitlab.io/AMR/articles/WHONET.html}{an example analysis using WHONET data}.
}

\examples{
# 10 random birth dates
df <- data.frame(birth_date = Sys.Date() - runif(10) * 25000)
# add ages
df$age <- age(df$birth_date)
# add exact ages
df$age_exact <- age(df$birth_date, exact = TRUE)

df
}
\seealso{
\code{\link{age_groups}} to split age into age groups
}