> >From a quick look, it appears the algorithms below don't allow for years
> that are multiples of 400 to be leap years, so might not work for 2000 (as
> well as 1600, which is not so important, as the Gregorian calendar suffered
> a big one-time adjustment jump in 1852, I think. I don't think anyone is
> now using the Julian calendar, which preceded the current Gregorian calendar
> and had major errors, but are numbering days serially based on the Julian
> period, devised by Scaliger and named after his father.
If I remember the source correctly, that comes from Astronomical
Formulae for Calculators by Jean Meeus. It does take the Gregorian
reform into account, and it should be solid regarding the leap years.
Andy
