软件包：libkal-dev（0.9.0-3.1） [debports]
library for converting dates between various calendar systems
The 'libkal' library provides support for converting dates between various calendar systems (currently only Julian, Gregorian, Arabic and Jewish ones) and some more related stuff.
The basic idea of this library is, that any date in any calendar system can be converted to a single number, which express the number of days since some fixed date in the past. libkal uses the so-called 'julianic date'(jd), that is used in Astronomy (not exactly).