diff options
Diffstat (limited to 'src/solar_python.py')
| -rw-r--r-- | src/solar_python.py | 73 |
1 files changed, 41 insertions, 32 deletions
diff --git a/src/solar_python.py b/src/solar_python.py index 2fa2d2d..e35c299 100644 --- a/src/solar_python.py +++ b/src/solar_python.py @@ -14,8 +14,6 @@ # You should have received a copy of the GNU Affero General Public License # along with this program. If not, see <http://www.gnu.org/licenses/>. -from math import * -import time SOLAR_APPARENT_RADIUS = 32 / 60 @@ -146,6 +144,7 @@ def epoch(): @return :float The current POSIX time ''' + import time return time.time() @@ -174,7 +173,8 @@ def radians(deg): @param deg:float The angle in degrees @return :float The angle in radians ''' - return deg * pi / 180 + import math + return deg * math.pi / 180 def degrees(rad): @@ -184,7 +184,8 @@ def degrees(rad): @param rad:float The angle in radians @return :float The angle in degrees ''' - return rad * 180 / pi + import math + return rad * 180 / math.pi def sun_geometric_mean_longitude(t): @@ -239,10 +240,11 @@ def sun_equation_of_centre(t): @param t:float The time in Julian Centuries @return :float The Sun's equation of the centre, in radians ''' + import math 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 + rc = math.sin(1 * a) * (-0.000014 * t ** 2 - 0.004817 * t + 1.914602) + rc += math.sin(2 * a) * (-0.000101 * t + 0.019993) + rc += math.sin(3 * a) * 0.000289 return radians(rc) @@ -264,8 +266,9 @@ def sun_apparent_longitude(t): @param t:float The time in Julian Centuries @return :float The longitude, in radians ''' + import math rc = degrees(sun_real_longitude(t)) - 0.00569 - rc -= 0.00478 * sin(radians(-1934.136 * t + 125.04)) + rc -= 0.00478 * math.sin(radians(-1934.136 * t + 125.04)) return radians(rc) @@ -291,8 +294,9 @@ def corrected_mean_ecliptic_obliquity(t): @param t:float The time in Julian Centuries @return :float The mean obliquity, in radians ''' + import math rc = -1934.136 * t + 125.04 - rc = 0.00256 * cos(radians(rc)) + rc = 0.00256 * math.cos(radians(rc)) rc += degrees(mean_ecliptic_obliquity(t)) return radians(rc) @@ -304,9 +308,10 @@ def solar_declination(t): @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) + import math + rc = math.sin(corrected_mean_ecliptic_obliquity(t)) + rc *= math.sin(sun_apparent_longitude(t)) + return math.asin(rc) def equation_of_time(t): @@ -317,15 +322,16 @@ def equation_of_time(t): @param t:float The time in Julian Centuries @return :float The equation of time, in degrees ''' + import math 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) + y = math.tan(y / 2) ** 2 + rc = y * math.sin(2 * l) + rc += (4 * y * math.cos(2 * l) - 2) * e * math.sin(m) + rc -= 0.5 * y ** 2 * math.sin(4 * l) + rc -= 1.25 * e ** 2 * math.sin(2 * m) return 4 * degrees(rc) @@ -339,12 +345,13 @@ def hour_angle_from_elevation(latitude, declination, elevation): @param hour_angle:float The Sun's elevation, in degrees @return :float The solar hour angle, in degrees ''' + import math if elevation == 0: return 0 - rc = cos(abs(elevation)) - rc -= sin(radians(latitude)) * sin(declination) - rc /= cos(radians(latitude)) * cos(declination) - rc = acos(rc) + rc = math.cos(abs(elevation)) + rc -= math.sin(radians(latitude)) * math.sin(declination) + rc /= math.cos(radians(latitude)) * math.cos(declination) + rc = math.acos(rc) return -rc if (rc < 0) == (elevation < 0) else rc; @@ -358,10 +365,11 @@ def elevation_from_hour_angle(latitude, declination, hour_angle): @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) + import math + rc = math.cos(radians(latitude)) + rc *= math.cos(hour_angle) * math.cos(declination) + rc += math.sin(radians(latitude)) * math.sin(declination) + return math.asin(rc) def time_of_solar_noon(t, longitude): @@ -762,6 +770,7 @@ def past_elevation_derivative(latitude, longitude, derivative, t = None): # TODO: This algorithm is imprecise, gives an incorrent sunrise and I do not fully know its behaviour def sunrise_equation(latitude, longitude, t = None): + import math # Calculate Julian Cycle j_cent = julian_centuries() if t is None else t j_date = julian_centuries_to_julian_day(j_cent) @@ -780,17 +789,17 @@ def sunrise_equation(latitude, longitude, t = None): 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) + solar_transit = approx_solar_noon + 0.0053 * math.sin(solar_mean_anomaly) + solar_transit -= 0.0069 * math.sin(2 * ecliptic_longitude) # Calculate solar declination - declination = asin(sin(ecliptic_longitude) * sin(radians(23.45))) + declination = math.asin(math.sin(ecliptic_longitude) * math.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)) + hour_angle = math.sin(radians(-0.83)) + hour_angle -= math.sin(latitude) * math.sin(declination) + hour_angle /= math.cos(latitude) * math.cos(declination) + hour_angle = degrees(math.acos(hour_angle)) # Calculate time of sunset and sunrise sunset = 2451545.0009 + (hour_angle + longitude) / 360 |