Sonnenuntergang/Rise -Berechnung ⇐ Python

[Anonymous]

Ich verwende die Suntime -Klasse, die basiert: "Berechnen Sie Sonnenaufgang und Sonnenuntergangszeiten für eine bestimmte GPS -Koordinate in Postgresql". Ich habe jedoch die Daten aus der Klasse überprüft und sie mit den Sunset/ Sunrise -Ereignissen von https://aa.usno.navy.mil/ über ein Jahr über ein Jahr verglichen. Ich bemerkte, dass einige Ereignisse mit einer Gewalt -Ranging -UT übersehen werden (insbesondere wenn 2 Sonnenuntergänge an einem Tag stattfinden). Dies kann verhindert werden, indem nicht der Kraftbereich verwendet wird. Aber ohne Kraft -Reichweite treten Fehler am ersten oder letzten Tag des Jahres auf. Irgendwie werden sie nicht richtig berechnet. Ich verstehe nicht ganz, wie ich das Überspringen des ersten und/oder letzten Jahres des Jahres verhindern kann, und Accuratley berechnet ihn ohne Gewaltbereich, was bei anderen Gelegenheiten Fehler verursacht. Außerdem funktioniert die Klasse großartig und ist genau das, was ich brauche. Vielleicht weiß jemand, wie man das behebt? Ich habe die Berechnung zwischen Sonnenzeit und USNO ohne erzwungene Reichweite angehängt. Berechnete Daten im Vergleich zu USNO -Daten < /p>

Code: Select all

TO_RAD = math.pi/180.0

class SunTimeException(Exception):

def __init__(self, message):
super(SunTimeException, self).__init__(message)

class Sun:
"""
Approximated calculation of sunrise and sunset datetimes. Adapted from:
https://stackoverflow.com/questions/19615350/calculate-sunrise-and-sunset-times-for-a-given-gps-coordinate-within-postgresql
"""
def __init__(self, lat, lon):
self._lat = lat
self._lon = lon

self.lngHour = self._lon / 15

def get_sunrise_time(self, at_date=datetime.now(), time_zone=timezone.utc):
"""
:param at_date: Reference date. datetime.now() if not provided.
:param time_zone: pytz object with .tzinfo() or None
:return: sunrise datetime.
:raises: SunTimeException when there is no sunrise and sunset on given location and date.
"""
time_delta = self.get_UT(at_date, time_zone=time_zone, is_rise_time=True)
if time_delta is None:
raise SunTimeException('The sun never rises on this location (on the specified date)')
elif isinstance(time_delta, str):
return time_delta
else:
event = datetime.combine(at_date, time(tzinfo=time_zone)) + time_delta
return event

def get_sunset_time(self, at_date=datetime.now(), time_zone=timezone.utc):
"""
Calculate the sunset time for given date.
:param at_date: Reference date. datetime.now() if not provided.
:param time_zone: pytz object with .tzinfo() or None
:return: sunset datetime.
:raises: SunTimeException when there is no sunrise and sunset on given location and date.
"""
time_delta = self.get_UT(at_date, time_zone=time_zone, is_rise_time=False)
if time_delta is None:
raise SunTimeException('The sun never rises on this location (on the specified date)')
elif isinstance(time_delta, str):
return time_delta
else:
event = datetime.combine(at_date, time(tzinfo=time_zone)) + time_delta
return event

def get_UT(self, at_date, time_zone, is_rise_time=True, zenith=90.8):
"""
Calculate sunrise or sunset date.
:param at_date: Reference date
:param time_zone: pytz object with .tzinfo() or None
:param is_rise_time: True if you want to calculate sunrise time.
:param zenith: Sun reference zenith
:return: timedelta showing hour, minute, and second of sunrise or sunset
"""

# If not set get local timezone from datetime
if time_zone is None:
time_zone = datetime.now().tzinfo

# 1. first get the day of the year
N = at_date.timetuple().tm_yday
# if at_date.date() == datetime(at_date.year, 1,1).date():
#     N = 0 #TODO: BAU DAS MIT DEN 3 OPTIONEN HIER EIN IN DER KLASSE. TESTE DAS.
# 2. convert the longitude to hour value and calculate an approximate time
if is_rise_time:
t = N + ((6 - self.lngHour) / 24)
else:   # sunset
t = N + ((18 - self.lngHour) / 24)

# 3a. calculate the Sun's mean anomaly
M = (0.9856 * t) - 3.289

# 3b. calculate the Sun's true longitude
L = M + (1.916 * math.sin(TO_RAD*M)) + (0.020 * math.sin(TO_RAD * 2 * M)) + 282.634
L = self._force_range(L, 360)   # NOTE: L adjusted into the range [0,360)

# 4a.  calculate the Sun's declination
sinDec = 0.39782 * math.sin(TO_RAD*L)
cosDec = math.cos(math.asin(sinDec))

# 4b. calculate the Sun's local hour angle
cosH = (math.cos(TO_RAD*zenith) - (sinDec * math.sin(TO_RAD*self._lat))) / (cosDec * math.cos(TO_RAD*self._lat))

if cosH > 1:
return "constant_eclipse"     #TODO: -->eclipse # The sun never rises on this location (on the specified date)
if cosH < -1:
return "constant_sun"     #TODO: -->daylight The sun never sets on this location (on the specified date)

# 4c. finish calculating H and convert into hours
if is_rise_time:
H = 360 - (1/TO_RAD) * math.acos(cosH)
else:   # setting
H = (1/TO_RAD) * math.acos(cosH)
H = H / 15

# 5a. calculate the Sun's right ascension
RA = (1/TO_RAD) * math.atan(0.91764 * math.tan(TO_RAD*L))
RA = self._force_range(RA, 360)     # NOTE: RA adjusted into the range [0,360)

# 5b. right ascension value needs to be in the same quadrant as L
Lquadrant = (math.floor(L/90)) * 90
RAquadrant = (math.floor(RA/90)) * 90
RA = RA + (Lquadrant - RAquadrant)

# 5c. right ascension value needs to be converted into hours
RA = RA / 15

# 6. calculate local mean time of rising/setting
T = H + RA - (0.06571 * t) - 6.622

# 7a. adjust back to UTC
UT = T - self.lngHour

if time_zone:
# 7b. adjust back to local time
UT += time_zone.utcoffset(at_date).total_seconds() / 3600

# 7c. rounding and impose range bounds
UT = round(UT, 2)
# NOTE: UT with force range : miss events, without: problems for 01.01/31.12
# UT = self._force_range(UT, 24)
# NOTE: original code, force range only for rise time
# if is_rise_time:
#     UT = self._force_range(UT, 24)

# 8. return timedelta
return timedelta(hours=UT)
#return UT

@staticmethod
def _force_range(v, max):
# force v to be >= 0 and < max
if v < 0:
return v + max
elif v >= max:
return v - max
return v