Most recent change of WhatDayIsEaster

Edit made on November 07, 2008 by DerekCouzens at 16:18:20

Deleted text in red / Inserted text in green

WW
HEADERS_END
How to work out the date of Easter Sunday for any year

* A mod b means “the remainder when A is divided by b” i.e. 23 mod 4 = 3

* M div n means “the value of M ÷ n forgetting the remainder” i.e. 23 div 4 = 5

Let g = (Y mod 19) + 1 where Y is the year
** Let g = (Y mod 19) + 1 where Y is the year

Let C = (Y div 100) + 1
** Let C = (Y div 100) + 1

Let X = (3C div 4) - 12
** Let X = (3C div 4) - 12

Let Z = ((8C + 5) div 25) - 5
** Let Z = ((8C + 5) div 25) - 5

Let D = (5Y div 4) - X - 10
** Let D = (5Y div 4) - X - 10

Let E = (11G + 20 + Z - X) mod 30
** Let E = (11G + 20 + Z - X) mod 30

If E = 25 and G greater than 11, or if E = 24, then increase E by 1
** If E = 25 and G greater than 11, or if E = 24, then increase E by 1

Let N = 44 – E
** Let N = 44 – E

If N is less than 21, increase N by 30
** If N is less than 21, increase N by 30

Let P = N + 7 - ((D + N) mod 7)
** Let P = N + 7 - ((D + N) mod 7)

If P is greater than 31, Easter Sunday is on (P - 31) April, Otherwise it is on P March
** If P is greater than 31, Easter Sunday is on (P - 31) April, Otherwise it is on P March

It may be easier to buy a diary!!!