Module calendrica-iso

ISO week-date calendar conversions.

Ported from "Calendrical Calculations" (4th edition) by Nachum Dershowitz and Edward M. Reingold. Original Lisp code (CALENDRICA 4.0) is Apache 2.0 licensed.

Functions

fixed_from_iso (i_date) Fixed date equivalent to ISO date `i_date`.
iso_from_fixed (date) ISO date {year, week, day} corresponding to fixed `date`.
iso_long_year (i_year) True if ISO year `i_year` is a long year (53 weeks).


Functions

fixed_from_iso (i_date)
Fixed date equivalent to ISO date `i_date`.

Parameters:

  • i_date table ISO date {year, week, day}.

Returns:

    number Fixed date.
iso_from_fixed (date)
ISO date {year, week, day} corresponding to fixed `date`.

Parameters:

  • date number Fixed date.

Returns:

    table {year, week, day}
iso_long_year (i_year)
True if ISO year `i_year` is a long year (53 weeks).

Parameters:

  • i_year number ISO year.

Returns:

    boolean
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