The calendar extension presents a series of
functions to simplify converting between different
calendar formats. The intermediary or standard it is
based on is the Julian Day Count. The Julian Day Count
is a count of days starting from January 1st, 4713 B.C.
To convert between calendar systems, you must first
convert to Julian Day Count, then to the calendar
system of your choice. Julian Day Count is very
different from the Julian Calendar! For more
information on Julian Day Count, visit
http://serendipity.magnet.ch/hermetic/cal_stud/jdn.htm.
For more information on calendar systems visit
http://genealogy.org/~scottlee/cal-overview.html.
Excerpts from this page are included in these
instructions, and are in quotes.
To get these functions to work, you have to
compile PHP with
--enable-calendar.
The windows version of PHP
has built in support for this extension. You do not
need to load any additional extension in order to use
these functions.
以下的常數由此延伸定義, 只在這個延伸被編譯成PHP或實行時期被動態載入時有效。
The following constants are available since PHP 4.3.0 :