SickGear/lib/dateutil/easter.py
echel0n 0d9fbc1ad7 Welcome to our SickBeard-TVRage Edition ...
This version of SickBeard uses both TVDB and TVRage to search and gather it's series data from allowing you to now have access to and download shows that you couldn't before because of being locked into only what TheTVDB had to offer.

Also this edition is based off the code we used in our XEM editon so it does come with scene numbering support as well as all the other features our XEM edition has to offer.

Please before using this with your existing database (sickbeard.db) please make a backup copy of it and delete any other database files such as cache.db and failed.db if present, we HIGHLY recommend starting out with no database files at all to make this a fresh start but the choice is at your own risk!

Enjoy!
2014-03-09 22:39:12 -07:00

92 lines
2.6 KiB
Python

"""
Copyright (c) 2003-2007 Gustavo Niemeyer <gustavo@niemeyer.net>
This module offers extensions to the standard python 2.3+
datetime module.
"""
__author__ = "Gustavo Niemeyer <gustavo@niemeyer.net>"
__license__ = "PSF License"
import datetime
__all__ = ["easter", "EASTER_JULIAN", "EASTER_ORTHODOX", "EASTER_WESTERN"]
EASTER_JULIAN = 1
EASTER_ORTHODOX = 2
EASTER_WESTERN = 3
def easter(year, method=EASTER_WESTERN):
"""
This method was ported from the work done by GM Arts,
on top of the algorithm by Claus Tondering, which was
based in part on the algorithm of Ouding (1940), as
quoted in "Explanatory Supplement to the Astronomical
Almanac", P. Kenneth Seidelmann, editor.
This algorithm implements three different easter
calculation methods:
1 - Original calculation in Julian calendar, valid in
dates after 326 AD
2 - Original method, with date converted to Gregorian
calendar, valid in years 1583 to 4099
3 - Revised method, in Gregorian calendar, valid in
years 1583 to 4099 as well
These methods are represented by the constants:
EASTER_JULIAN = 1
EASTER_ORTHODOX = 2
EASTER_WESTERN = 3
The default method is method 3.
More about the algorithm may be found at:
http://users.chariot.net.au/~gmarts/eastalg.htm
and
http://www.tondering.dk/claus/calendar.html
"""
if not (1 <= method <= 3):
raise ValueError, "invalid method"
# g - Golden year - 1
# c - Century
# h - (23 - Epact) mod 30
# i - Number of days from March 21 to Paschal Full Moon
# j - Weekday for PFM (0=Sunday, etc)
# p - Number of days from March 21 to Sunday on or before PFM
# (-6 to 28 methods 1 & 3, to 56 for method 2)
# e - Extra days to add for method 2 (converting Julian
# date to Gregorian date)
y = year
g = y % 19
e = 0
if method < 3:
# Old method
i = (19*g+15)%30
j = (y+y//4+i)%7
if method == 2:
# Extra dates to convert Julian to Gregorian date
e = 10
if y > 1600:
e = e+y//100-16-(y//100-16)//4
else:
# New method
c = y//100
h = (c-c//4-(8*c+13)//25+19*g+15)%30
i = h-(h//28)*(1-(h//28)*(29//(h+1))*((21-g)//11))
j = (y+y//4+i+2-c+c//4)%7
# p can be from -6 to 56 corresponding to dates 22 March to 23 May
# (later dates apply to method 2, although 23 May never actually occurs)
p = i-j+e
d = 1+(p+27+(p+6)//40)%31
m = 3+(p+26)//30
return datetime.date(int(y),int(m),int(d))