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Get number of days after March 21 on which Easter falls for a given year
(PHP 4, PHP 5)
Example 368. easter_days() example<?phpCode Examples / Notes » easter_daysmartin
This function appears to be Britanno-centric. When attempting to calculate the Gregorian date for Easter for years prior to 1753, the function returns the number or days since March 21st in the Julian Calendar, even though the Gregorian system was in effect in the rest of Europe since 1582. If you wish to calculate the date of easter for a Gregorian date from 1582 onward, use the following function, which duplicates the funcionality of easter_days: function easter_days2($year) { #First calculate the date of easter using Delambre's algorithm. $a = $year % 19; $b = floor($year / 100); $c = $year % 100; $d = floor($b / 4); $e = $b % 4; $f = floor(($b + 8) / 25); $g = floor(($b - $f + 1) / 3); $h = (19 * $a + $b - $d - $g + 15) % 30; $i = floor($c / 4); $k = $c % 4; $l = (32 + 2 * $e + 2 * $i - $h - $k) % 7; $m = floor(($a + 11 * $h + 22 * $l) / 451); $n = ($h + $l - 7 * $m + 114); $month = floor($n / 31); $day = $n % 31 + 1; #Return the difference between the JulianDayCount for easter and March 21'st #of the same year, in order to duplicate the functionality of the easter_days function return GregorianToJD($month, $day, $year) - GregorianToJD(3,21,$year); } ian
Also, be aware that the eastern orthodox churches sometimes have different dates for easter. See, for example <http://webexhibits.org/calendars/calendar-christian-easter.html>. And note that the dates of easter a subject to change, for example, the churches might some day decide to unify the dates.
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