Module calendrica-bahai
Baha'i calendar conversions (arithmetic and astronomical).
Ported from "Calendrical Calculations" (4th edition) by Nachum Dershowitz and Edward M. Reingold. Original Lisp code (CALENDRICA 4.0) is Apache 2.0 licensed.
Info:
- Release: 0.1 2026-07-19
Functions
| fixed_from_bahai (b_date) | Fixed date equivalent to the Baha'i date `b_date`. |
| bahai_from_fixed (date) | Baha'i date {major, cycle, year, month, day} corresponding to fixed `date`. |
| bahai_new_year (g_year) | Fixed date of arithmetic Bahá'í New Year (always March 21) in Gregorian year `g_year`. |
| fixed_from_astro_bahai (b_date) | Fixed date of astronomical Baha'i date `b_date`. |
| astro_bahai_from_fixed (date) | Astronomical Baha'i date {major,cycle,year,month,day} corresponding to fixed `date`. |
| naw_ruz (g_year) | Fixed date of Bahá'í New Year (Naw-Rúz) in Gregorian year `g_year`. |
| feast_of_ridvan (g_year) | Fixed date of the Feast of Riḍván in Gregorian year `g_year`. |
| birth_of_the_bab (g_year) | Fixed date of the Birthday of the Báb in Gregorian year `g_year`. |
Fields
| AYYAM_I_HA | Intercalary month number (0) inserted before the last month of the year. |
Functions
- fixed_from_bahai (b_date)
-
Fixed date equivalent to the Baha'i date `b_date`.
Parameters:
- b_date table Baha'i date {major, cycle, year, month, day}.
Returns:
-
number
Fixed date.
- bahai_from_fixed (date)
-
Baha'i date {major, cycle, year, month, day} corresponding to fixed `date`.
Parameters:
- date number Fixed date.
Returns:
-
table
{major, cycle, year, month, day}
- bahai_new_year (g_year)
-
Fixed date of arithmetic Bahá'í New Year (always March 21) in Gregorian year `g_year`.
For the astronomical version based on the vernal equinox, use `naw_ruz`.
Parameters:
- g_year number Gregorian year.
Returns:
-
number
Fixed date.
- fixed_from_astro_bahai (b_date)
-
Fixed date of astronomical Baha'i date `b_date`.
Parameters:
- b_date table Baha'i date {major, cycle, year, month, day}.
Returns:
-
number
Fixed date.
- astro_bahai_from_fixed (date)
-
Astronomical Baha'i date {major,cycle,year,month,day} corresponding to fixed `date`.
Parameters:
- date number Fixed date.
Returns:
-
table
{major, cycle, year, month, day}
- naw_ruz (g_year)
-
Fixed date of Bahá'í New Year (Naw-Rúz) in Gregorian year `g_year`.
Parameters:
- g_year number Gregorian year.
Returns:
-
number
Fixed date.
- feast_of_ridvan (g_year)
-
Fixed date of the Feast of Riḍván in Gregorian year `g_year`.
Parameters:
- g_year number Gregorian year.
Returns:
-
number
Fixed date.
- birth_of_the_bab (g_year)
-
Fixed date of the Birthday of the Báb in Gregorian year `g_year`.
Parameters:
- g_year number Gregorian year.
Returns:
-
number
Fixed date.