NAME Date::JD - conversion between flavours of Julian Date DESCRIPTION For date and time calculations it is convenient to represent dates by a simple linear count of days, rather than in a particular calendar. This is such a good idea that it has been invented several times. If there were a single such linear count then it would be the obvious data interchange format between calendar modules. With several versions, calendar modules can use such sensible data formats and still have interoperability problems. This module tackles that problem, by performing conversions between different flavours of day count. These day count systems are generically known as "Julian Dates", after the most venerable of them. Among Julian Date systems there are also some non-trivial differences of concept. There are systems that count only complete days, and those that count fractional days also. There are some that are fixed to Universal Time (time on the prime meridian), and others that are interpreted according to a timezone. Some consider the day to start at noon and others at midnight, which is semantically significant for the complete-day counts. The functions of this module appropriately handle the semantics of all the non-trivial conversions. The day count systems supported by this module are Julian Date, Reduced Julian Date, Modified Julian Date, Dublin Julian Date, Truncated Julian Date, Chronological Julian Date, Rata Die, and Lilian Date, each in both integral and fractional forms. INSTALLATION perl Build.PL ./Build ./Build test ./Build install AUTHOR Andrew Main (Zefram) COPYRIGHT Copyright (C) 2006, 2007, 2009, 2010 Andrew Main (Zefram) LICENSE This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself.