diff options
| -rw-r--r-- | DEPENDENCIES | 3 | ||||
| -rwxr-xr-x | src/__main__.py | 2 | ||||
| -rw-r--r-- | src/adhoc.py | 2 | ||||
| -rw-r--r-- | src/solar.py | 782 |
4 files changed, 6 insertions, 783 deletions
diff --git a/DEPENDENCIES b/DEPENDENCIES index 0f1082d..d190dd6 100644 --- a/DEPENDENCIES +++ b/DEPENDENCIES @@ -2,6 +2,8 @@ RUNTIME DEPENDENCIES: python3 + solar-python + argparser-python (required but can function partially if missing) libxcb (opt-out) @@ -45,6 +47,7 @@ MAKE DEPENDENCIES: DEPENDENCY SOURCES: + solar-python https://github.com/maandree/solar-python argparser-python https://github.com/maandree/argparser adjbacklight https://github.com/maandree/adjbacklight auto-auto-complete https://github.com/maandree/auto-auto-complete diff --git a/src/__main__.py b/src/__main__.py index b58cfdc..e93b196 100755 --- a/src/__main__.py +++ b/src/__main__.py @@ -561,7 +561,7 @@ if have_argparser: None, True, ArgParser.standard_abbreviations()) # Populate parser with possible options - dn = '\nUse twice or daytime and nighttime respectively' + dn = '\nUse twice for daytime and nighttime respectively' parser.add_argumented(['-c', '--configurations'], 0, 'FILE', 'Select configuration file') parser.add_argumentless(['-p', '--panic-gate', '--panicgate'], 0, 'Skip transition into initial settings') parser.add_argumented(['-g', '--gamma'], 0, 'RGB|R:G:B', 'Set gamma correction' + dn) diff --git a/src/adhoc.py b/src/adhoc.py index 8d3a57f..0751b1a 100644 --- a/src/adhoc.py +++ b/src/adhoc.py @@ -41,7 +41,7 @@ if (rgb_temperatures is None) and (cie_temperatures is None): # to 3700 K during the day, and 6500 K (neutral) during # the night. Do not use CIE xyY, hence set cie_temperatures # to 6500 K (neutral). - rgb_temperatures = ['3700', '6500'] + rgb_temperatures = ['3500', '5500'] cie_temperatures = ['6500', '6500'] else: # If cie_temperatures is specified but not rgb_temperatures, diff --git a/src/solar.py b/src/solar.py index 38fa11b..c8bbea1 100644 --- a/src/solar.py +++ b/src/solar.py @@ -17,58 +17,7 @@ # This module implements algorithms for calculating information about the Sun. -from math import * -import time - - -SOLAR_ELEVATION_SUNSET_SUNRISE = 0.0 -''' -:float The Sun's elevation at sunset and sunrise, - measured in degrees -''' - -SOLAR_ELEVATION_CIVIL_DUSK_DAWN = -6.0 -''' -:float The Sun's elevation at civil dusk and civil - dawn, measured in degrees -''' - -SOLAR_ELEVATION_NAUTICAL_DUSK_DAWN = -12.0 -''' -:float The Sun's elevation at nautical dusk and - nautical dawn, measured in degrees -''' - -SOLAR_ELEVATION_ASTRONOMICAL_DUSK_DAWN = -18.0 -''' -:float The Sun's elevation at astronomical dusk - and astronomical dawn, measured in degrees -''' - -SOLAR_ELEVATION_RANGE_TWILIGHT = (-18.0, 0.0) -''' -:(float, float) The Sun's lowest and highest elevation during - all periods of twilight, measured in degrees -''' - -SOLAR_ELEVATION_RANGE_CIVIL_TWILIGHT = (-6.0, 0.0) -''' -:(float, float) The Sun's lowest and highest elevation - during civil twilight, measured in degrees -''' - -SOLAR_ELEVATION_RANGE_NAUTICAL_TWILIGHT = (-12.0, -6.0) -''' -:(float, float) The Sun's lowest and highest elevation - during nautical twilight, measured in degrees -''' - -SOLAR_ELEVATION_RANGE_ASTRONOMICAL_TWILIGHT = (-18.0, -12.0) -''' -:(float, float) The Sun's lowest and highest elevation during - astronomical twilight, measured in degrees -''' - +from solar_python import * def sun(latitude, longitude, t = None, low = -6.0, high = 3.0): @@ -89,735 +38,6 @@ def sun(latitude, longitude, t = None, low = -6.0, high = 3.0): return min(max(0, e), 1) - -# The following functions are used to calculate the result for `sun` -# (most of them) but could be used for anything else. There name is -# should tell you enough, `t` (and `noon`) is in Julian centuries -# except for in the convertion methods. - - -def julian_day_to_epoch(t): - ''' - Converts a Julian Day timestamp to a POSIX time timestamp - - @param t:float The time in Julian Days - @return :float The time in POSIX time - ''' - return (t - 2440587.5) * 86400.0 - - -def epoch_to_julian_day(t): - ''' - Converts a POSIX time timestamp to a Julian Day timestamp - - @param t:float The time in POSIX time - @return :float The time in Julian Days - ''' - return t / 86400.0 + 2440587.5 - - -def julian_day_to_julian_centuries(t): - ''' - Converts a Julian Day timestamp to a Julian Centuries timestamp - - @param t:float The time in Julian Days - @return :float The time in Julian Centuries - ''' - return (t - 2451545.0) / 36525.0 - - -def julian_centuries_to_julian_day(t): - ''' - Converts a Julian Centuries timestamp to a Julian Day timestamp - - @param t:float The time in Julian Centuries - @return :float The time in Julian Days - ''' - return t * 36525.0 + 2451545.0 - - -def epoch_to_julian_centuries(t): - ''' - Converts a POSIX time timestamp to a Julian Centuries timestamp - - @param t:float The time in POSIX time - @return :float The time in Julian Centuries - ''' - return julian_day_to_julian_centuries(epoch_to_julian_day(t)) - - -def julian_centuries_to_epoch(t): - ''' - Converts a Julian Centuries timestamp to a POSIX time timestamp - - @param t:float The time in Julian Centuries - @return :float The time in POSIX time - ''' - return julian_day_to_epoch(julian_centuries_to_julian_day(t)) - - -def epoch(): - ''' - Get current POSIX time - - @return :float The current POSIX time - ''' - return time.time() - - -def julian_day(): - ''' - Get current Julian Day time - - @return :float The current Julian Day time - ''' - return epoch_to_julian_day(epoch()) - - -def julian_centuries(): - ''' - Get current Julian Centuries time (100 Julian days since J2000) - - @return :float The current Julian Centuries time - ''' - return epoch_to_julian_centuries(epoch()) - - -def radians(deg): - ''' - Convert an angle from degrees to radians - - @param deg:float The angle in degrees - @return :float The angle in radians - ''' - return deg * pi / 180 - - -def degrees(rad): - ''' - Convert an angle from radians to degrees - - @param rad:float The angle in radians - @return :float The angle in degrees - ''' - return rad * 180 / pi - - -def sun_geometric_mean_longitude(t): - ''' - Calculates the Sun's geometric mean longitude - - @param t:float The time in Julian Centuries - @return :float The Sun's geometric mean longitude in radians - ''' - return radians((0.0003032 * t ** 2 + 36000.76983 * t + 280.46646) % 360) - # CANNIBALISERS: - # The result of this function should always be positive, this - # means that after division modulo 360 but before `radians`, - # you will need to add 360 if the value is negative. This can - # only happen if `t` is negative, which can only happen for date - # times before 2000-(01)Jan-01 12:00:00 UTC par division modulo - # implementations with the signess of atleast the left operand. - # More precively, it happens between cirka 1970-(01)Jan-11 - # 16:09:02 UTC and cirka -374702470660351740 seconds before - # January 1, 1970 00:00 UTC, which is so far back in time - # it cannot be reliable pinned down to the right year, but it - # is without a shadow of a doubt looooong before the Earth - # was formed, is right up there with the age of the Milky Way - # and the universe itself. - - -def sun_geometric_mean_anomaly(t): - ''' - Calculates the Sun's geometric mean anomaly - - @param t:float The time in Julian Centuries - @return :float The Sun's geometric mean anomaly in radians - ''' - return radians(-0.0001537 * t ** 2 + 35999.05029 * t + 357.52911) - - -def earth_orbit_eccentricity(t): - ''' - Calculates the Earth's orbit eccentricity - - @param t:float The time in Julian Centuries - @return :float The Earth's orbit eccentricity - ''' - return -0.0000001267 * t ** 2 - 0.000042037 * t + 0.016708634 - - -def sun_equation_of_centre(t): - ''' - Calculates the Sun's equation of the centre, the difference between - the true anomaly and the mean anomaly - - @param t:float The time in Julian Centuries - @return :float The Sun's equation of the centre, in radians - ''' - a = sun_geometric_mean_anomaly(t) - rc = sin(1 * a) * (-0.000014 * t ** 2 - 0.004817 * t + 1.914602) - rc += sin(2 * a) * (-0.000101 * t + 0.019993) - rc += sin(3 * a) * 0.000289 - return radians(rc) - - -def sun_real_longitude(t): - ''' - Calculates the Sun's real longitudinal position - - @param t:float The time in Julian Centuries - @return :float The longitude, in radians - ''' - rc = sun_geometric_mean_longitude(t) - return rc + sun_equation_of_centre(t) - - -def sun_apparent_longitude(t): - ''' - Calculates the Sun's apparent longitudinal position - - @param t:float The time in Julian Centuries - @return :float The longitude, in radians - ''' - rc = degrees(sun_real_longitude(t)) - 0.00569 - rc -= 0.00478 * sin(radians(-1934.136 * t + 125.04)) - return radians(rc) - - -def mean_ecliptic_obliquity(t): - ''' - Calculates the mean ecliptic obliquity of the Sun's - apparent motion without variation correction - - @param t:float The time in Julian Centuries - @return :float The uncorrected mean obliquity, in radians - ''' - rc = 0.001813 * t ** 3 - 0.00059 * t ** 2 - 46.815 * t + 21.448 - rc = 26 + rc / 60 - rc = 23 + rc / 60 - return radians(rc) - - -def corrected_mean_ecliptic_obliquity(t): - ''' - Calculates the mean ecliptic obliquity of the Sun's - apparent motion with variation correction - - @param t:float The time in Julian Centuries - @return :float The mean obliquity, in radians - ''' - rc = -1934.136 * t + 125.04 - rc = 0.00256 * cos(radians(rc)) - rc += degrees(mean_ecliptic_obliquity(t)) - return radians(rc) - - -def solar_declination(t): - ''' - Calculates the Sun's declination - - @param t:float The time in Julian Centuries - @return :float The Sun's declination, in radians - ''' - rc = sin(corrected_mean_ecliptic_obliquity(t)) - rc *= sin(sun_apparent_longitude(t)) - return asin(rc) - - -def equation_of_time(t): - ''' - Calculates the equation of time, the discrepancy - between apparent and mean solar time - - @param t:float The time in Julian Centuries - @return :float The equation of time, in degrees - ''' - l = sun_geometric_mean_longitude(t) - e = earth_orbit_eccentricity(t) - m = sun_geometric_mean_anomaly(t) - y = corrected_mean_ecliptic_obliquity(t) - y = tan(y / 2) ** 2 - rc = y * sin(2 * l) - rc += (4 * y * cos(2 * l) - 2) * e * sin(m) - rc -= 0.5 * y ** 2 * sin(4 * l) - rc -= 1.25 * e ** 2 * sin(2 * m) - return 4 * degrees(rc) - - -def hour_angle_from_elevation(latitude, declination, elevation): - ''' - Calculates the solar hour angle from the Sun's elevation - - @param longitude:float The longitude in degrees eastwards - from Greenwich, negative for westwards - @param declination:float The declination, in degrees - @param hour_angle:float The Sun's elevation, in degrees - @return :float The solar hour angle, in degrees - ''' - if elevation == 0: - return 0 - rc = cos(abs(elevation)) - rc -= sin(radians(latitude)) * sin(declination) - rc /= cos(radians(latitude)) * cos(declination) - rc = acos(rc) - return -rc if (rc < 0) == (elevation < 0) else rc; - - -def elevation_from_hour_angle(latitude, declination, hour_angle): - ''' - Calculates the Sun's elevation from the solar hour angle - - @param longitude:float The longitude in degrees eastwards - from Greenwich, negative for westwards - @param declination:float The declination, in degrees - @param hour_angle:float The solar hour angle, in degrees - @return :float The Sun's elevation, in degrees - ''' - rc = cos(radians(latitude)) - rc *= cos(hour_angle) * cos(declination) - rc += sin(radians(latitude)) * sin(declination) - return asin(rc) - - -def time_of_solar_noon(t, longitude): - ''' - Calculates the time of the closest solar noon - - @param t:float A time close to the seeked time, - in Julian Centuries - @param longitude:float The longitude in degrees eastwards from - Greenwich, negative for westwards - @return :float The time, in Julian Centuries, - of the closest solar noon - ''' - t, rc = julian_centuries_to_julian_day(t), longitude - for (k, m) in ((-360, 0), (1440, -0.5)): - rc = julian_day_to_julian_centuries(t + m + rc / k) - rc = 720 - 4 * longitude - equation_of_time(rc) - return rc - - -def time_of_solar_elevation(t, noon, latitude, longitude, elevation): - ''' - Calculates the time the Sun has a specified apparent - elevation at a geographical position - - @param t:float A time close to the seeked time, - in Julian Centuries - @param noon:float The time of the closest solar noon - @param latitude:float The latitude in degrees northwards from - the equator, negative for southwards - @param longitude:float The longitude in degrees eastwards from - Greenwich, negative for westwards - @param elevation:float The solar elevation, in degrees - @return :float The time, in Julian Centuries, - of the specified elevation - ''' - rc = noon - rc, et = solar_declination(rc), equation_of_time(rc) - rc = hour_angle_from_elevation(latitude, rc, elevation) - rc = 720 - 4 * (longitude + degrees(rc)) - et - - rc = julian_day_to_julian_centuries(julian_centuries_to_julian_day(t) + rc / 1440) - rc, et = solar_declination(rc), equation_of_time(rc) - rc = hour_angle_from_elevation(latitude, rc, elevation) - rc = 720 - 4 * (longitude + degrees(rc)) - et - return rc - - -def solar_elevation_from_time(t, latitude, longitude): - ''' - Calculates the Sun's elevation as apparent - from a geographical position - - @param t:float The time in Julian Centuries - @param latitude:float The latitude in degrees northwards from - the equator, negative for southwards - @param longitude:float The longitude in degrees eastwards from - Greenwich, negative for westwards - @return :float The Sun's apparent at the specified time - as seen from the specified position, - measured in degrees - ''' - rc = julian_centuries_to_julian_day(t) - rc = (rc - float(int(rc + 0.5)) - 0.5) * 1440 - rc = 720 - rc - equation_of_time(t) - rc = radians(rc / 4 - longitude) - return elevation_from_hour_angle(latitude, solar_declination(t), rc) - - -def solar_elevation(latitude, longitude, t = None): - ''' - Calculates the Sun's elevation as apparent - from a geographical position - - @param latitude:float The latitude in degrees northwards from - the equator, negative for southwards - @param longitude:float The longitude in degrees eastwards from - Greenwich, negative for westwards - @param t:float? The time in Julian Centuries, `None` - for the current time - @return :float The Sun's apparent at the specified time - as seen from the specified position, - measured in degrees - ''' - rc = julian_centuries() if t is None else t - rc = solar_elevation_from_time(rc, latitude, longitude) - return degrees(rc) - - - -def have_sunrise_and_sunset(latitude, t = None): - ''' - Determine whether solar declination currently is - so that there can be sunrises and sunsets. If not, - you either have 24-hour daytime or 24-hour nighttime. - - @param latitude:float The latitude in degrees northwards from - the equator, negative for southwards - @param t:float? The time in Julian Centuries, `None` - for the current time - @return Whether there can be sunrises and - sunsets where you are located - ''' - t = julian_centuries() if t is None else t - d = degrees(solar_declination(t)) - ## Covert everything to the Northern hemisphere - latitude = abs(latitude) - if d >= 0: - ## Northern summer - return -90 + d < latitude < 90 - d - else: - ## Northern winter - return -90 - d < latitude < 90 + d - - -def is_summer(latitude, t = None): - ''' - Determine whether it is summer - - @param latitude:float The latitude in degrees northwards from - the equator, negative for southwards - @param t:float? The time in Julian Centuries, `None` - for the current time - @return Whether it is summer on the hemisphere - you are located on - ''' - t = julian_centuries() if t is None else t - d = solar_declination(t) - return (d > 0) == (latitude > 0) - - -def is_winter(latitude, t = None): - ''' - Determine whether it is winter - - @param latitude:float The latitude in degrees northwards from - the equator, negative for southwards - @param t:float? The time in Julian Centuries, `None` - for the current time - @return Whether it is winter on the hemisphere - you are located on - ''' - t = julian_centuries() if t is None else t - d = solar_declination(t) - return not ((d > 0) == (latitude > 0)) - - - -def solar_prediction(delta, requested, fun, epsilon = 0.000001, span = 0.01, t = None): - ''' - Predict the time point of the next or previous - time an arbitrary condition is meet - - @param delta:float Iteration step size, negative for past - event, positive for future event - @param requested:float The value returned by `fun` for which to - calculate the time point of occurrence - @param fun:(t:float)→float Function that calculate the data of interest - @param epsilon:float Error tolerance for `requested` - @param span:float The number of Julian centuries (0,01 for - one year) to restrict the search to - @param t:float? The time in Julian Centuries, `None` for - the current time - @return :float? The calculated time point, `None` if none - were found within the specified time span - ''' - t = julian_centuries() if t is None else t - t1 = t2 = t - v1 = v0 = fun(t) - while True: - if abs(t2 - t) > span: - return None - t2 += delta - v2 = fun(t2) - if (v1 <= requested <= v2) or ((requested >= v1 >= v2) and (requested <= v0)): - break - if (v1 >= requested >= v2) or ((requested <= v1 <= v2) and (requested >= v0)): - break - t1 = t2 - v2 = v1 - for _itr in range(1000): - tm = (t1 + t2) / 2 - v1 = fun(t1) - v2 = fun(t2) - vm = fun(tm) - if abs(v1 - v2) < epsilon: - return tm if abs(vm) < epsilon else None - if v1 < v2: - if requested < vm: - t2 = tm - else: - t1 = tm - elif v1 > v2: - if requested > vm: - t2 = tm - else: - t1 = tm - return None - - - -def future_past_equinox(delta, t = None): - ''' - Predict the time point of the next or previous equinox - - @param delta:float Iteration step size, negative for - past event, positive for future event - @param t:float? The time in Julian Centuries, `None` - for the current time - @return :float The calculated time point - ''' - return solar_prediction(delta, 0, solar_declination, t = t) - - -def future_equinox(t = None): - ''' - Predict the time point of the next equinox - - @param delta:float Iteration step size, negative for - past event, positive for future event - @param t:float? The time in Julian Centuries, `None` - for the current time - @return :float The calculated time point - ''' - return future_past_equinox(0.01 / 2000, t) - - -def past_equinox(t = None): - ''' - Predict the time point of the previous equinox - - @param delta:float Iteration step size, negative for - past event, positive for future event - @param t:float? The time in Julian Centuries, `None` - for the current time - @return :float The calculated time point - ''' - return future_past_equinox(0.01 / -2000, t) - - - -def future_past_solstice(delta, t = None): - ''' - Predict the time point of the next or previous solstice - - @param delta:float Iteration step size, negative for - past event, positive for future event - @param t:float? The time in Julian Centuries, `None` - for the current time - @return :float The calculated time point - ''' - e = 0.00001 - fun = solar_declination - dfun = lambda t : (fun(t + e) - fun(t - e)) / 2 - return solar_prediction(delta, 0, dfun, t = t) - - -def future_solstice(t = None): - ''' - Predict the time point of the next solstice - - @param t:float? The time in Julian Centuries, - `None` for the current time - @return :float The calculated time point - ''' - return future_past_solstice(0.01 / 2000, t) - - -def past_solstice(t = None): - ''' - Predict the time point of the previous solstice - - @param t:float? The time in Julian Centuries, - `None` for the current time - @return :float The calculated time point - ''' - return future_past_solstice(0.01 / -2000, t) - - - -def future_past_elevation(delta, latitude, longitude, elevation, t = None): - ''' - Predict the time point of the next or previous time - the Sun reaches or reached a specific elevation - - @param delta:float Iteration step size, negative for past - event, positive for future event - @param latitude:float The latitude in degrees northwards from - the equator, negative for southwards - @param longitude:float The longitude in degrees eastwards from - Greenwich, negative for westwards - @param elevation:float The elevation of interest - @param t:float? The time in Julian Centuries, `None` - for the current time - @return :float? The calculated time point, `None` if - none were found within a year - ''' - fun = lambda t : solar_elevation(latitude, longitude, t) - return solar_prediction(delta, elevation, fun, t = t) - - -def future_elevation(latitude, longitude, elevation, t = None): - ''' - Predict the time point of the next time the Sun - reaches a specific elevation - - @param latitude:float The latitude in degrees northwards from - the equator, negative for southwards - @param longitude:float The longitude in degrees eastwards from - Greenwich, negative for westwards - @param elevation:float The elevation of interest - @param t:float? The time in Julian Centuries, `None` - for the current time - @return :float? The calculated time point, `None` if - none were found within a year - ''' - return future_past_elevation(0.01 / 2000, latitude, longitude, elevation, t) - - -def past_elevation(latitude, longitude, elevation, t = None): - ''' - Predict the time point of the previous time the Sun - reached a specific elevation - - @param latitude:float The latitude in degrees northwards from - the equator, negative for southwards - @param longitude:float The longitude in degrees eastwards from - Greenwich, negative for westwards - @param elevation:float The elevation of interest - @param t:float? The time in Julian Centuries, `None` - for the current time - @return :float? The calculated time point, `None` if - none were found within a year - ''' - return future_past_elevation(0.01 / -2000, latitude, longitude, elevation, t) - - - -def future_past_elevation_derivative(delta, latitude, longitude, derivative, t = None): - ''' - Predict the time point of the next or previous time the - Sun reaches or reached a specific elevation derivative - - @param delta:float Iteration step size, negative for past - event, positive for future event - @param latitude:float The latitude in degrees northwards from - the equator, negative for southwards - @param longitude:float The longitude in degrees eastwards from - Greenwich, negative for westwards - @param derivative:float The elevation derivative value of interest - @param t:float? The time in Julian Centuries, `None` - for the current time - @return :float? The calculated time point, `None` if - none were found within a year - ''' - fun = lambda t : solar_elevation(latitude, longitude, t) - dfun = lambda t : (fun(t + e) - fun(t - e)) / 2 - return solar_prediction(delta, derivative, dfun, t = t) - - -def future_elevation_derivative(latitude, longitude, derivative, t = None): - ''' - Predict the time point of the next time the - Sun reaches a specific elevation derivative - - @param latitude:float The latitude in degrees northwards from - the equator, negative for southwards - @param longitude:float The longitude in degrees eastwards from - Greenwich, negative for westwards - @param derivative:float The elevation derivative value of interest - @param t:float? The time in Julian Centuries, `None` - for the current time - @return :float? The calculated time point, `None` if - none were found within a year - ''' - return future_past_elevation_derivative(0.01 / 2000, latitude, longitude, derivative, t) - - -def past_elevation_derivative(latitude, longitude, derivative, t = None): - ''' - Predict the time point of the previous time - the Sun reached a specific elevation derivative - - @param latitude:float The latitude in degrees northwards from - the equator, negative for southwards - @param longitude:float The longitude in degrees eastwards from - Greenwich, negative for westwards - @param derivative:float The elevation derivative value of interest - @param t:float? The time in Julian Centuries, `None` - for the current time - @return :float? The calculated time point, `None` - if none were found within a year - ''' - return future_past_elevation_derivative(0.01 / -2000, latitude, longitude, derivative, t) - - - -# TODO: This algorithm is imprecise, gives an incorrent sunrise and I do not fully know its behaviour -def sunrise_equation(latitude, longitude, t = None): - # Calculate Julian Cycle - j_cent = julian_centuries() if t is None else t - j_date = julian_centuries_to_julian_day(j_cent) - j_cycle = int(j_date - 2451545.0009 - longitude / 360 + 0.5) - - # Calculate approximate solar noon and solar man anomaly - approx_solar_noon = 451545.0009 + longitude / 360 + j_cycle - solar_mean_anomaly = int(357.5291 + 0.98560028 * (j_cycle - 2451545)) % 360 - - # Calculate solar equation of centre - equation_of_centre = 1.9148 * sin(1 * solar_mean_anomaly) - equation_of_centre += 0.0200 * sin(2 * solar_mean_anomaly) - equation_of_centre += 0.0003 * sin(3 * solar_mean_anomaly) - - # Calculate solar ecliptic longitude - ecliptic_longitude = (solar_mean_anomaly + 102.9372 + equation_of_centre + 180) % 360 - - # Calculate solar transit - solar_transit = approx_solar_noon + 0.0053 * sin(solar_mean_anomaly) - solar_transit -= 0.0069 * sin(2 * ecliptic_longitude) - - # Calculate solar declination - declination = asin(sin(ecliptic_longitude) * sin(radians(23.45))) - - # Calculate solar hour angle - hour_angle = sin(radians(-0.83)) - hour_angle -= sin(latitude) * sin(declination) - hour_angle /= cos(latitude) * cos(declination) - hour_angle = degrees(acos(hour_angle)) - - # Calculate time of sunset and sunrise - sunset = 2451545.0009 + (hour_angle + longitude) / 360 - sunset += j_cycle + solar_transit - approx_solar_noon - sunrise = 2 * solar_transit - sunset - - # Convert to Julian Centuries - return (julian_day_to_julian_centuries(sunset), - julian_day_to_julian_centuries(sunrise)) - - - def ptime(t): ''' Print a time stamp in human-readable local time |