def format_long_line(satrec, mu, r, v):
"""Long line, using the same format string that testcpp.cpp uses."""
short = format_short_line(satrec, r, v).strip("\n")
jd = satrec.jdsatepoch + satrec.t / 1440.0
year, mon, day, hr, minute, sec = invjday(jd)
(p, a, ecc, incl, node, argp, nu, m, arglat, truelon, lonper) = rv2coe(r, v, mu)
return short + (" %14.6f %8.6f %10.5f %10.5f %10.5f %10.5f %10.5f" " %5i%3i%3i %2i:%2i:%9.6f\n") % (
a,
ecc,
incl * rad,
node * rad,
argp * rad,
nu * rad,
m * rad,
year,
mon,
day,
hr,
minute,
sec,
)
def format_long_line(satrec, tsince, mu, r, v):
"""Long line, using the same format string that testcpp.cpp uses."""
short = format_short_line(tsince, r, v).strip('\n')
jd = satrec.jdsatepoch + satrec.jdsatepochF + tsince / 1440.0
year, mon, day, hr, minute, sec = invjday(jd)
(p, a, ecc, incl, node, argp, nu, m, arglat, truelon,
lonper) = rv2coe(r, v, mu)
return short + (' %14.6f %8.6f %10.5f %10.5f %10.5f %10.5f %10.5f'
' %5i%3i%3i %2i:%2i:%9.6f\n') % (
a,
ecc,
incl * rad,
node * rad,
argp * rad,
nu * rad,
m * rad,
year,
mon,
day,
hr,
minute,
sec,
)
def Position_and_Velocity(self, time): '''This function generates the barycentric position and velocity of the orbital body at a specified time with the use of the SGP4 propogator.''' #The time to find the position and velocity at t = time #The first line of the orbital body's TLE line1 = self.TLE_line1 #The second line of the orbital body's TLE line2 = self.TLE_line2 #Fictitiously instantiate a SGP4 satellite object sat = twoline2rv(line1, line2, gravity_constant) #Convert Julian date to conventional time_conv = invjday(time) #Compute the geocentric position and velocity of the orbital body p, v = sat.propagate(*time_conv) #Turn the tuples into arrays p = np.asarray(p) v = np.asarray(v) #Convert km to m p = p * 1e3 #Convert km/s to m/s v = v * 1e3 #Compute the barycentric position and velocity of the attracting body P, V = self.attracting_body.Position_and_Velocity(time) #Compute the barycentric position of the orbital body p = p + P #compute the barycentric velocity of the orbital body v = v + V return p, v
def VMS_Julian2Time(inJul, format='%Y%m%d%H%M%S'):
tFormat = format #"%d-%b-%Y %H:%M:%S"
try: #see if it is a list
for i in inJul:
a = invjday(i)
aTime = dt.datetime.timetuple(
dt.datetime(a[0], a[1], a[2], a[3], a[4], int(a[5])))
aStr = time.strftime(tFormat, aTime)
try:
out.append(aStr)
except:
out = [aStr]
return out
except: #a single shot
a = invjday(inJul)
aTime = dt.datetime.timetuple(
dt.datetime(a[0], a[1], a[2], a[3], a[4], int(a[5])))
return time.strftime(tFormat, aTime)
def sgp4init(self, whichconst, opsmode, satnum, epoch, bstar,
ndot, nddot, ecco, argpo, inclo, mo, no_kozai, nodeo):
whichconst = gravity_constants[whichconst]
y, m, d, H, M, S = invjday(epoch + 2433281.5)
jan0epoch = jday(y, 1, 0, 0, 0, 0.0) - 2433281.5
self.epochyr = y % 1000
self.epochdays = epoch - jan0epoch
self.jdsatepoch, self.jdsatepochF = divmod(epoch, 1.0)
self.jdsatepoch += 2433281.5
sgp4init(whichconst, opsmode, satnum, epoch, bstar, ndot, nddot,
ecco, argpo, inclo, mo, no_kozai, nodeo, self)
def envicosmos(tle1,tle2):
whichconst = 'wgs72'
#whichconst = wgs72
f1=open(tle1+'.tle')
f2=open(tle2+'.tle')
out1=open('envi.sal','w+')
out2=open('cosmos.sal','w+')
archivos=[f1,f2]
var=0
for tlefile in archivos:
var = var + 1
tlelines = iter(tlefile.readlines())
for line1 in tlelines:
if not line1.startswith('1'):
continue
line2 = next(tlelines)
satrec = twoline2rv(line1, line2, whichconst) # es un objeto de clase (satelite)
mu = satrec.whichconst.mu
epocatle=satrec.jdsatepoch
print 'epoca del tle [jd] = ', epocatle
jdini=jday(2008,1,9,18,0,0.0)
tini=(jdini-epocatle)*1440.0
print(tini)
tintervalo=np.arange(0,7200,1)
for t1 in tintervalo:
t=tini+t1/60.0
r, v = sgp4(satrec, t)
tjd=epocatle+t/1440.0 # dia juliano correspondiente al t en min.
"""Impresion de salida"""
year, mon, day, hr, minute, sec = invjday(tjd)
fecha = str(year)+'/'+str(mon)+'/'+str(day)+' '+str(hr)+':'+\
str(minute)+':'+str(sec)+' '+str(tjd)+' '+str(r[0])+' '+\
str(r[1])+' '+str(r[2])+' '+str(v[0])+' '+\
str(v[1])+' '+str(v[2])+'\n'
if var == 1:
out1.write(fecha)
else:
out2.write(fecha)
# year2,mon2,day2,hr2,minu2,sec2=invjday(2454475.29201)
# print year2,mon2,day2,hr2,minu2,sec2
"""
def test_jday(self):
print("jday...")
jd = 2454115.05486 # Sunday 14 January 2007 at 13:18:59.9
# Reference Astropy as "answer"
t_astropy = Time(jd, format='jd')
jdF = jd-int(jd)
jd = int(jd)
jday_datetime = jday_to_datetime(jd, jdF)
self.assertRegex(jday_datetime.isoformat(sep=' ',timespec='milliseconds'),t_astropy.iso,msg="jday_to_datetime() failed")
(year, month, day, hour, minute, second) = invjday(jd)
jday_jd = jday(year, month, day, hour, minute, second)
self.assertEqual(jday_jd,jd,"jday() failed")
def Position_and_Velocity_Satellite(satellite, time):
# The first line of the TLE
line1 = satellite.line1
# The second line
line2 = satellite.line2
# Fictitious SGP4 satellite object
sat = twoline2rv(line1, line2, grav_const)
# Convert Julian date to conventional
time_conv = invjday(time)
# The position and velocity of the satellite
pv = np.asarray(sat.propagate(*time_conv))
# Convert km to m and km/s to m/s
pv = np.multiply(pv, 1e3)
# The attracting body ephemeris
PV = satellite.attracting_body.Position_and_Velocity(time)
# Convert from geocentric to barycentric frame
pv = np.add(pv, PV)
return pv
def twoline2rv(longstr1, longstr2, whichconst, opsmode='i', satrec=None):
"""Return a Satellite imported from two lines of TLE data.
Provide the two TLE lines as strings `longstr1` and `longstr2`,
and select which standard set of gravitational constants you want
by providing `gravity_constants`:
`sgp4.earth_gravity.wgs72` - Standard WGS 72 model
`sgp4.earth_gravity.wgs84` - More recent WGS 84 model
`sgp4.earth_gravity.wgs72old` - Legacy support for old SGP4 behavior
Normally, computations are made using various recent improvements
to the algorithm. If you want to turn some of these off and go
back into "opsmode" mode, then set `opsmode` to `a`.
"""
deg2rad = pi / 180.0
# 0.0174532925199433
xpdotp = 1440.0 / (2.0 * pi)
# 229.1831180523293
# For compatibility with our 1.x API, build an old Satellite object
# if the caller fails to supply a satrec. In that case we perform
# the necessary import here to avoid an import loop.
if satrec is None:
from sgp4.model import Satellite
satrec = Satellite()
satrec.error = 0
satrec.whichconst = whichconst # Python extension: remembers its consts
line = longstr1.rstrip()
if (len(line) >= 64 and line.startswith('1 ') and line[8] == ' '
and line[23] == '.' and line[32] == ' ' and line[34] == '.'
and line[43] == ' ' and line[52] == ' ' and line[61] == ' '
and line[63] == ' '):
_saved_satnum = satrec.satnum = _alpha5(line[2:7])
satrec.classification = line[7] or 'U'
satrec.intldesg = line[9:17].rstrip()
two_digit_year = int(line[18:20])
satrec.epochdays = float(line[20:32])
satrec.ndot = float(line[33:43])
satrec.nddot = float(line[44] + '.' + line[45:50])
nexp = int(line[50:52])
satrec.bstar = float(line[53] + '.' + line[54:59])
ibexp = int(line[59:61])
satrec.ephtype = line[62]
satrec.elnum = int(line[64:68])
else:
raise ValueError(error_message.format(1, LINE1, line))
line = longstr2.rstrip()
if (len(line) >= 69 and line.startswith('2 ') and line[7] == ' '
and line[11] == '.' and line[16] == ' ' and line[20] == '.'
and line[25] == ' ' and line[33] == ' ' and line[37] == '.'
and line[42] == ' ' and line[46] == '.' and line[51] == ' '):
satrec.satnum = _alpha5(line[2:7])
if _saved_satnum != satrec.satnum:
raise ValueError('Object numbers in lines 1 and 2 do not match')
satrec.inclo = float(line[8:16])
satrec.nodeo = float(line[17:25])
satrec.ecco = float('0.' + line[26:33].replace(' ', '0'))
satrec.argpo = float(line[34:42])
satrec.mo = float(line[43:51])
satrec.no_kozai = float(line[52:63])
satrec.revnum = line[63:68]
#except (AssertionError, IndexError, ValueError):
else:
raise ValueError(error_message.format(2, LINE2, line))
# ---- find no, ndot, nddot ----
satrec.no_kozai = satrec.no_kozai / xpdotp
# rad/min
satrec.nddot = satrec.nddot * pow(10.0, nexp)
satrec.bstar = satrec.bstar * pow(10.0, ibexp)
# ---- convert to sgp4 units ----
satrec.ndot = satrec.ndot / (xpdotp * 1440.0)
# ? * minperday
satrec.nddot = satrec.nddot / (xpdotp * 1440.0 * 1440)
# ---- find standard orbital elements ----
satrec.inclo = satrec.inclo * deg2rad
satrec.nodeo = satrec.nodeo * deg2rad
satrec.argpo = satrec.argpo * deg2rad
satrec.mo = satrec.mo * deg2rad
"""
// ----------------------------------------------------------------
// find sgp4epoch time of element set
// remember that sgp4 uses units of days from 0 jan 1950 (sgp4epoch)
// and minutes from the epoch (time)
// ----------------------------------------------------------------
// ---------------- temp fix for years from 1957-2056 -------------------
// --------- correct fix will occur when year is 4-digit in tle ---------
"""
if two_digit_year < 57:
year = two_digit_year + 2000
else:
year = two_digit_year + 1900
mon, day, hr, minute, sec = days2mdhms(year, satrec.epochdays)
sec_whole, sec_fraction = divmod(sec, 1.0)
satrec.epochyr = year
satrec.jdsatepoch = jday(year, mon, day, hr, minute, sec)
try:
satrec.epoch = datetime(year, mon, day, hr, minute, int(sec_whole),
int(sec_fraction * 1000000.0 // 1.0))
except ValueError:
# Sometimes a TLE says something like "2019 + 366.82137887 days"
# which would be December 32nd which causes a ValueError.
year, mon, day, hr, minute, sec = invjday(satrec.jdsatepoch)
satrec.epoch = datetime(year, mon, day, hr, minute, int(sec_whole),
int(sec_fraction * 1000000.0 // 1.0))
# ---------------- initialize the orbit at sgp4epoch -------------------
sgp4init(whichconst, opsmode, satrec.satnum, satrec.jdsatepoch - 2433281.5,
satrec.bstar, satrec.ndot, satrec.nddot, satrec.ecco,
satrec.argpo, satrec.inclo, satrec.mo, satrec.no_kozai,
satrec.nodeo, satrec)
return satrec
def jd2Date(self, jd):
return invjday(jd)
def datetime_from_jday(jd, fr):
year, mon, day, hr, minute, sec_float = invjday(jd + fr)
sec = int(sec_float)
microsec = int((sec_float - sec) * 1e6)
return dt.datetime(year, mon, day, hr, minute, sec, microsec)
def julian2dt(julday):
return invjday(inJul)
