This software calculates dates in the Gregorian calendar.
Date::Calc is a C library and Perl module that allows for various types of date calculations based on the Gregorian calendar. It aims to maintain compliance with all relevant norms and standards, including ISO/R 2015-1971, DIN 1355, and ISO 8601 where applicable.
One notable feature is its ability to handle year numbers of 2000 and above, ensuring "Year 2000" or "Y2K" compliance. The module can deal with all year numbers from 1 to the largest positive integer representable on your system (at least 32767).
It is important to note that the import/export functions in this package are an interface to the internal POSIX date and time functions of your system, which have limitations when it comes to date ranges. For example, Unix etc. can only cover dates in the range of 01-Jan-1970 00:00:00 GMT to 19-Jan-2038 03:14:07 GMT.
However, Date::Calc projects the Gregorian calendar back to year 1 A.D., despite the fact that the calendar was only adopted in 1582 in mostly Catholic European countries. Some (mainly protestant) countries continued to use the Julian calendar until the beginning of the 20th century.
This software package is intended to be a toolbox for date calculations instead of doing everything automatically. It is designed to follow the UNIX spirit and traditions and should always get you where you need to go. For common problems, there is a "RECIPES" section at the bottom of the document to provide solutions.
If there is a specific problem that you cannot solve, there is an email address at the end of the document to get in touch with support. Overall, Date::Calc is a fast, simple, and reliable software package for Gregorian calendar date calculations.
Version 6.3: N/A