Toms Homepage
  Home    Downloads    Your Account    Forums  
  Create an account
Modules
· Home
· Games
· PHP Manual
· PHP-Nuke HOWTO
 
easter_days

easter_days

(PHP 3>= 3.0.9, PHP 4 , PHP 5)

easter_days --  Get number of days after March 21 on which Easter falls for a given year

Description

int easter_days ( [int year [, int method]] )

Returns the number of days after March 21 on which Easter falls for a given year. If no year is specified, the current year is assumed.

Since PHP 4.3.0, the year parameter is optional and defaults to the current year according to the localtime if omitted.

The method parameter was also introduced in PHP 4.3.0 and allows to calculate easter dates based on the Gregorian calendar during the years 1582 - 1752 when set to CAL_EASTER_ROMAN. See the calendar constants for more valid constants.

This function can be used instead of easter_date() to calculate Easter for years which fall outside the range of Unix timestamps (i.e. before 1970 or after 2037).

Example 1. easter_days() example

<?php

echo easter_days(1999);        // 14, i.e. April 4
echo easter_days(1492);        // 32, i.e. April 22
echo easter_days(1913);        //  2, i.e. March 23

?>


The date of Easter Day was defined by the Council of Nicaea in AD325 as the Sunday after the first full moon which falls on or after the Spring Equinox. The Equinox is assumed to always fall on 21st March, so the calculation reduces to determining the date of the full moon and the date of the following Sunday. The algorithm used here was introduced around the year 532 by Dionysius Exiguus. Under the Julian Calendar (for years before 1753) a simple 19-year cycle is used to track the phases of the Moon. Under the Gregorian Calendar (for years after 1753 - devised by Clavius and Lilius, and introduced by Pope Gregory XIII in October 1582, and into Britain and its then colonies in September 1752) two correction factors are added to make the cycle more accurate.

(The code is based on a C program by Simon Kershaw, <webmaster at ely.anglican dot org>)

See also easter_date().

All logos and trademarks in this site are property of their respective owner. The comments are property of their posters, all the rest 2004 by Tom Nitzschner.
Web site engine code is Copyright © 2003 by PHP-Nuke. All Rights Reserved. PHP-Nuke is Free Software released under the GNU/GPL license.
Page Generation: 0.088 Seconds

:: VereorLCARS phpbb2 style by Vereor :: PHP-Nuke theme by www.nukemods.com ::