[PYTHON/DATETIME] 특정 주차(Week Number)의 첫번째 날짜 구하기

■ 특정 주차(Week Number)의 첫번째 날짜를 구하는 방법을 보여준다.

 

▶ 예제 코드 (PY)

import datetime

def GetWeekNumberFirstDate(year, weekNumber):
    yearFirstDate = datetime.datetime(year, 1, 1)
    currentDate   = yearFirstDate + datetime.timedelta(weeks = weekNumber - 1)
    targetDate    = currentDate - datetime.timedelta(days = currentDate.isoweekday() % 7 - 1)
    return targetDate

if __name__ == "__main__":
    print(GetWeekNumberFirstDate(2019, 1)) # 2018-12-31 00:00:00
    print(GetWeekNumberFirstDate(2019, 2)) # 2019-01-07 00:00:00
    print(GetWeekNumberFirstDate(2019, 3)) # 2019-01-14 00:00:00
    print(GetWeekNumberFirstDate(2019, 4)) # 2019-01-21 00:00:00
    print(GetWeekNumberFirstDate(2019, 5)) # 2019-01-28 00:00:00
    print(GetWeekNumberFirstDate(2019, 6)) # 2019-02-04 00:00:00