eeptools (version 0.3.1)

age_calc: Function to calculate age from date of birth.

Description

This function calculates age in days, months, or years from a date of birth to another arbitrary date. This returns a numeric vector in the specified units.

Usage

age_calc(dob, enddate = Sys.Date(), units = "months", precise = TRUE)

Arguments

dob

a vector of class Date representing the date of birth/start date

enddate

a vector of class Date representing the when the observation's age is of interest, defaults to current date.

units

a string that indicates units of age

precise

logical indicating whether or not to calculate with leap year and leap second precision

Value

• a vector of class numeric

source

This function was developed in part from this response on the R-Help mailing list. https://stat.ethz.ch/pipermail/r-help/2009-November/217649.html

See Also

See also difftime which this function uses and mimics some functionality but at higher unit levels.

Examples

a <- as.Date(seq(as.POSIXct('1987-05-29 018:07:00'), len=26, by="21 day"))
b <- as.Date(seq(as.POSIXct('2002-05-29 018:07:00'), len=26, by="21 day"))

age <- age_calc(a, units='years')
age
age <- age_calc(a, units='months')
age
age <- age_calc(a, as.Date('2005-09-01'))
age