def from_fixed(cls, fixed_date):
"""Return Chinese date (cycle year month leap day) of fixed date, 'fixed_date'."""
s1 = cls.winter_solstice_on_or_before(fixed_date)
s2 = cls.winter_solstice_on_or_before(s1 + 370)
next_m11 = cls.new_moon_before(1 + s2)
m12 = cls.new_moon_on_or_after(1 + s1)
leap_year = iround((next_m11 - m12) / Lunar.MEAN_SYNODIC_MONTH) == 12
m = cls.new_moon_before(1 + fixed_date)
month = amod(iround((m - m12) / Lunar.MEAN_SYNODIC_MONTH) - (1 if (leap_year and cls.is_prior_leap_month(m12, m)) else 0), 12)
leap_month = (leap_year and cls.is_no_major_solar_term(m) and (not cls.is_prior_leap_month(m12, cls.new_moon_before(m))))
elapsed_years = (ifloor(mpf(1.5) - (month / 12) + ((fixed_date - cls.EPOCH) / Solar.MEAN_TROPICAL_YEAR)))
cycle = 1 + quotient(elapsed_years - 1, 60)
year = amod(elapsed_years, 60)
day = 1 + (fixed_date - m)
return ChineseDate(cycle, year, month, leap_month, day)
def from_fixed(cls, fixed_date):
"""Return French Revolutionary date of fixed date, 'fixed_date'."""
new_year = cls.new_year_on_or_before(fixed_date)
year = iround((new_year - cls.EPOCH) / Solar.MEAN_TROPICAL_YEAR) + 1
month = quotient(fixed_date - new_year, 30) + 1
day = mod(fixed_date - new_year, 30) + 1
return FrenchDate(year, month, day)
def to_fixed(self):
"""Return fixed date equivalent to Observational Hebrew date."""
year1 = self.year - 1 if self.month >= HebrewMonth.TISHRI else self.year
start = HebrewDate(year1, HebrewMonth.NISAN, 1).to_fixed()
g_year = GregorianDate.to_year(start + 60)
new_year = self.new_year(g_year)
midmonth = new_year + iround(29.5 * (self.month - 1)) + 15
return JAFFA.phasis_on_or_before(midmonth) + self.day - 1
def from_fixed(cls, fixed_date):
"""Return Observational Islamic date (year month day)
corresponding to fixed date, 'fixed_date'."""
crescent = cls.LOCATION.phasis_on_or_before(fixed_date)
elapsed_months = iround((crescent - cls.EPOCH) / Lunar.MEAN_SYNODIC_MONTH)
year = quotient(elapsed_months, 12) + 1
month = mod(elapsed_months, 12) + 1
day = (fixed_date - crescent) + 1
return ObservationalIslamicDate(year, month, day)
def from_fixed(cls, fixed_date):
"""Return Observational Hebrew date (year month day)
corresponding to fixed date, 'fixed_date'."""
crescent = JAFFA.phasis_on_or_before(fixed_date)
g_year = GregorianDate.to_year(fixed_date)
ny = cls.new_year(g_year)
new_year = cls.new_year(g_year - 1) if (fixed_date < ny) else ny
month = iround((crescent - new_year) / 29.5) + 1
year = HebrewDate.from_fixed(new_year).year + (1 if month >= HebrewMonth.TISHRI else 0)
day = fixed_date - crescent + 1
return HebrewObservationalDate(year, month, day)
def from_fixed(cls, date):
"""Return Astronomical Persian date (year month day)
corresponding to fixed date, date."""
new_year = cls.new_year_on_or_before(date)
y = iround((new_year - cls.EPOCH) / Solar.MEAN_TROPICAL_YEAR) + 1
year = y if (0 < y) else (y - 1)
day_of_year = date - PersianDate(year, 1, 1).to_fixed() + 1
month = (iceiling(day_of_year / 31)
if (day_of_year <= 186)
else iceiling((day_of_year - 6) / 30))
day = date - (PersianDate(year, month, 1).to_fixed() - 1)
return PersianDate(year, month, day)
def lunar_phase(cls, tee):
"""Return the lunar phase, as an angle in degrees, at moment tee.
An angle of 0 means a new moon, 90 degrees means the
first quarter, 180 means a full moon, and 270 degrees
means the last quarter."""
phi = mod(cls.lunar_longitude(tee) - Solar.solar_longitude(tee), 360)
t0 = cls.nth_new_moon(0)
n = iround((tee - t0) / cls.MEAN_SYNODIC_MONTH)
phi_prime = (360 *
mod((tee - cls.nth_new_moon(n)) / cls.MEAN_SYNODIC_MONTH, 1))
if abs(phi - phi_prime) > 180:
return phi_prime
else:
return phi
def new_year_in_sui(cls, fixed_date):
"""Return fixed date of Chinese New Year in sui (period from
solstice to solstice) containing date, 'fixed_date'."""
s1 = cls.winter_solstice_on_or_before(fixed_date)
s2 = cls.winter_solstice_on_or_before(s1 + 370)
next_m11 = cls.new_moon_before(1 + s2)
m12 = cls.new_moon_on_or_after(1 + s1)
m13 = cls.new_moon_on_or_after(1 + m12)
leap_year = iround((next_m11 - m12) / Lunar.MEAN_SYNODIC_MONTH) == 12
if (leap_year and
(cls.is_no_major_solar_term(m12) or cls.is_no_major_solar_term(m13))):
return cls.new_moon_on_or_after(1 + m13)
else:
return m13
def from_fixed(cls, fixed_date):
"""Return Future Bahai date corresponding to fixed date, 'fixed_date'."""
new_year = cls.new_year_on_or_before(fixed_date)
years = iround((new_year - cls.EPOCH) / Solar.MEAN_TROPICAL_YEAR)
major = 1 + quotient(years, 361)
cycle = 1 + quotient(mod(years, 361), 19)
year = 1 + mod(years, 19)
days = fixed_date - new_year
if fixed_date >= FutureBahaiDate(major, cycle, year, 19, 1).to_fixed():
month = 19
elif fixed_date >= FutureBahaiDate(major, cycle, year, cls.AYYAM_I_HA, 1).to_fixed():
month = cls.AYYAM_I_HA
else:
month = 1 + quotient(days, 19)
day = fixed_date + 1 - FutureBahaiDate(major, cycle, year, month, 1).to_fixed()
return FutureBahaiDate(major, cycle, year, month, day)
def calendar_year(cls, tee):
"""Return the astronomical Hindu solar year KY at given moment, tee."""
return iround(((tee - OldHindu.EPOCH) / cls.MEAN_SIDEREAL_YEAR) - (sidereal_solar_longitude(tee) / 360))
def calendar_year(cls, tee):
"""Return the solar year at given moment, tee."""
return iround(((tee - OldHindu.EPOCH) / cls.SIDEREAL_YEAR) - (cls.solar_longitude(tee) / 360))
def alt_sunrise(cls, date):
"""Return the astronomical sunrise at Hindu location on date, date,
per Lahiri, rounded to nearest minute, as a rational number."""
rise = cls.UJJAIN.dawn(date, angle(0, 47, 0))
return 1/24 * 1/60 * iround(rise * 24 * 60)
def sine_table(cls, entry):
"""Return the value for entry in the Hindu sine table.
Entry, entry, is an angle given as a multiplier of 225'."""
exact = 3438 * sin_degrees(entry * angle(0, 225, 0))
error = 0.215 * signum(exact) * signum(abs(exact) - 1716)
return iround(exact + error) / 3438
def new_moon_at_or_after(cls, tee):
"""Return the moment UT of first new moon at or after moment, tee."""
t0 = cls.nth_new_moon(0)
phi = cls.lunar_phase(tee)
n = iround((tee - t0) / cls.MEAN_SYNODIC_MONTH - phi / 360)
return cls.nth_new_moon(next_int(n, lambda k: cls.nth_new_moon(k) >= tee))
def new_moon_before(cls, tee):
"""Return the moment UT of last new moon before moment tee."""
t0 = cls.nth_new_moon(0)
phi = cls.lunar_phase(tee)
n = iround(((tee - t0) / cls.MEAN_SYNODIC_MONTH) - (phi / 360))
return cls.nth_new_moon(final_int(n - 1, lambda k: cls.nth_new_moon(k) < tee))
