def rise(jd, raList, decList, h0, delta):
"""Return the Julian Day of the rise time of an object.
Parameters:
jd : Julian Day number of the day in question, at 0 hr UT
raList : a sequence of three right accension values, in radians,
for (jd-1, jd, jd+1)
decList : a sequence of three right declination values, in radians,
for (jd-1, jd, jd+1)
h0 : the standard altitude in radians
delta : desired accuracy in days. Times less than one minute are
infeasible for rise times because of atmospheric refraction.
Returns:
Julian Day of the rise time
"""
longitude = astronomia.globals.longitude
latitude = astronomia.globals.latitude
THETA0 = sidereal_time_greenwich(jd)
deltaT_days = deltaT_seconds(jd) / seconds_per_day
cosH0 = (sin(h0) - sin(latitude) * sin(decList[1])) / (cos(latitude) * cos(decList[1]))
#
# future: return some indicator when the object is circumpolar or always
# below the horizon.
#
if cosH0 < -1.0: # circumpolar
return None
if cosH0 > 1.0: # never rises
return None
H0 = acos(cosH0)
m0 = (raList[1] + longitude - THETA0) / pi2
m = m0 - H0 / pi2 # this is the only difference between rise() and set()
if m < 0:
m += 1
elif m > 1:
m -= 1
if not 0 <= m <= 1:
raise Error, "m is out of range = " + str(m)
for bailout in range(20):
m0 = m
theta0 = modpi2(THETA0 + _k1 * m)
n = m + deltaT_days
if not -1 < n < 1:
return None # Bug: this is where we drop some events
ra = interpolate_angle3(n, raList)
dec = interpolate3(n, decList)
H = theta0 - longitude - ra
# if H > pi:
# H = H - pi2
H = diff_angle(0.0, H)
A, h = equ_to_horiz(H, dec)
dm = (h - h0) / (pi2 * cos(dec) * cos(latitude) * sin(H))
m += dm
if abs(m - m0) < delta:
return jd + m
raise Error, "bailout"
def _riseset(jd, raList, decList, h0, delta, mode,
longitude=astronomia.globals.longitude,
latitude=astronomia.globals.latitude):
# Private function since rise/set so similar
THETA0 = sidereal_time_greenwich(jd)
deltaT_days = deltaT_seconds(jd) / seconds_per_day
cosH0 = (np.sin(h0) - np.sin(latitude)*np.sin(decList[1])) / (
np.cos(latitude)*np.cos(decList[1]))
#
# future: return some indicator when the object is circumpolar or always
# below the horizon.
#
if cosH0 < -1.0: # circumpolar
return None
if cosH0 > 1.0: # never rises
return None
H0 = np.arccos(cosH0)
m0 = (raList[1] + longitude - THETA0) / pi2
if mode == 'rise':
m = m0 - H0 / pi2 # the only difference between rise() and settime()
elif mode == 'set':
m = m0 + H0 / pi2 # the only difference between rise() and settime()
if m < 0:
m += 1
elif m > 1:
m -= 1
if not 0 <= m <= 1:
raise Error("m is out of range = " + str(m))
for bailout in range(20):
m0 = m
theta0 = modpi2(THETA0 + _k1 * m)
n = m + deltaT_days
if not -1 < n < 1:
return None # Bug: this is where we drop some events
ra = interpolate_angle3(n, raList)
dec = interpolate3(n, decList)
H = theta0 - longitude - ra
# if H > pi:
# H = H - pi2
H = diff_angle(0.0, H)
A, h = equ_to_horiz(H, dec)
dm = (h - h0) / (pi2 * np.cos(dec) * np.cos(latitude) * np.sin(H))
m += dm
if abs(m - m0) < delta:
return jd + m
raise Error("bailout")
def transit(jd, raList, delta):
"""Return the Julian Day of the transit time of an object.
Parameters:
jd : Julian Day number of the day in question, at 0 hr UT
raList : a sequence of three right accension values, in radians,
for (jd-1, jd, jd+1)
delta : desired accuracy in days.
Returns:
Julian Day of the transit time
"""
#
# future: report both upper and lower culmination, and transits of objects below
# the horizon
#
longitude = astronomia.globals.longitude
THETA0 = sidereal_time_greenwich(jd)
deltaT_days = deltaT_seconds(jd) / seconds_per_day
m = (raList[1] + longitude - THETA0) / pi2
if m < 0:
m += 1
elif m > 1:
m -= 1
if not 0 <= m <= 1:
raise Error, "m is out of range = " + str(m)
for bailout in range(20):
m0 = m
theta0 = modpi2(THETA0 + _k1 * m)
n = m + deltaT_days
if not -1 < n < 1:
return None # Bug: this is where we drop some events
ra = interpolate_angle3(n, raList)
H = theta0 - longitude - ra
# if H > pi:
# H = H - pi2
H = diff_angle(0.0, H)
dm = -H / pi2
m += dm
if abs(m - m0) < delta:
return jd + m
raise Error, "bailout"
def transit(jd, raList, delta):
"""Return the Julian Day of the transit time of an object.
Arguments:
- `jd` : Julian Day number of the day in question, at 0 hr UT
- `raList` : a sequence of three right accension values, in radians, for
(jd-1, jd, jd+1)
- `delta` : desired accuracy in days.
Returns:
- Julian Day of the transit time
"""
#
# future: report both upper and lower culmination, and transits of objects
# below the horizon
#
longitude = astronomia.globals.longitude
THETA0 = sidereal_time_greenwich(jd)
deltaT_days = deltaT_seconds(jd) / seconds_per_day
m = (raList[1] + longitude - THETA0) / pi2
if m < 0:
m += 1
elif m > 1:
m -= 1
if not 0 <= m <= 1:
raise Error("m is out of range = " + str(m))
for bailout in range(20):
m0 = m
theta0 = modpi2(THETA0 + _k1 * m)
n = m + deltaT_days
if not -1 < n < 1:
return None # Bug: this is where we drop some events
ra = interpolate_angle3(n, raList)
H = theta0 - longitude - ra
# if H > pi:
# H = H - pi2
H = diff_angle(0.0, H)
dm = -H/pi2
m += dm
if abs(m - m0) < delta:
return jd + m
raise Error("bailout")
def rise(jd, raList, decList, h0, delta):
"""Return the Julian Day of the rise time of an object.
Parameters:
jd : Julian Day number of the day in question, at 0 hr UT
raList : a sequence of three right accension values, in radians,
for (jd-1, jd, jd+1)
decList : a sequence of three right declination values, in radians,
for (jd-1, jd, jd+1)
h0 : the standard altitude in radians
delta : desired accuracy in days. Times less than one minute are
infeasible for rise times because of atmospheric refraction.
Returns:
Julian Day of the rise time
"""
longitude = astronomia.globals.longitude
latitude = astronomia.globals.latitude
THETA0 = sidereal_time_greenwich(jd)
deltaT_days = deltaT_seconds(jd) / seconds_per_day
cosH0 = (sin(h0) - sin(latitude) * sin(decList[1])) / (cos(latitude) *
cos(decList[1]))
#
# future: return some indicator when the object is circumpolar or always
# below the horizon.
#
if cosH0 < -1.0: # circumpolar
return None
if cosH0 > 1.0: # never rises
return None
H0 = acos(cosH0)
m0 = (raList[1] + longitude - THETA0) / pi2
m = m0 - H0 / pi2 # this is the only difference between rise() and set()
if m < 0:
m += 1
elif m > 1:
m -= 1
if not 0 <= m <= 1:
raise Error, "m is out of range = " + str(m)
for bailout in range(20):
m0 = m
theta0 = modpi2(THETA0 + _k1 * m)
n = m + deltaT_days
if not -1 < n < 1:
return None # Bug: this is where we drop some events
ra = interpolate_angle3(n, raList)
dec = interpolate3(n, decList)
H = theta0 - longitude - ra
# if H > pi:
# H = H - pi2
H = diff_angle(0.0, H)
A, h = equ_to_horiz(H, dec)
dm = (h - h0) / (pi2 * cos(dec) * cos(latitude) * sin(H))
m += dm
if abs(m - m0) < delta:
return jd + m
raise Error, "bailout"
def test_interpolate_angle3(self):
y = interpolate_angle3(0, (359, 0, 1))
self.assertAlmostEqual(y, 0.0, places=6)
