EpiWeek (version 1.1)

dateToEpiweek: Convert Calendar Dates to Epidemiological Weeks

Description

This function calculates the year and epidemiological week for a given calendar date. By definition, the first epidemiological week of the year contains at least four days in January.

Usage

dateToEpiweek(date, format = "%Y-%m-%d", firstday = "Sunday")

Arguments

date

A character string for calendar date.

format

A character string specifying the input format for date. The default for the format methods is "%Y-%m-%d".

firstday

A character string specifying the beginning weekday for each epidemiological week. The default for the firstday methods is "Sunday".

Value

year

Epidemiological year

weekno

Epidemiological week

Examples

dateToEpiweek("2015-01-06")
dateToEpiweek("2015-Jan-06",format="%Y-%b-%d")
dateToEpiweek("Feb-15-2016",format="%b-%d-%Y",firstday="Monday")