Get a date-to-epiyear function from an epiweek standard.

Get the function that converts dates to epiyear numbers for a given epiweek standard.

Usage

epiyear_fn(epiweek_standard)

Arguments

epiweek_standard

One of "MMWR" or "USA" (USA / MMWR epiweek, starts on Sunday) and "ISO" (ISO week, starts on Monday). Not case-sensitive. Must be a single value.

Value

A function, either lubridate::epiyear() or lubridate::isoyear(), depending on the value of epiweek_standard