def propagate(self, year, month=1, day=1, hour=0, minute=0, second=0.0):
"""Return a position and velocity vector for a given date and time."""
j = jday(year, month, day, hour, minute, second)
m = (j - self.jdsatepoch) * minutes_per_day
r, v = sgp4(self, m)
return r, v
def twoline2rv(longstr1, longstr2, whichconst, afspc_mode=False):
"""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 "afspc" mode, then set `afspc_mode` to `True`.
"""
opsmode = 'a' if afspc_mode else 'i'
deg2rad = pi / 180.0; # 0.0174532925199433
xpdotp = 1440.0 / (2.0 *pi); # 229.1831180523293
tumin = whichconst.tumin
satrec = Satellite()
satrec.error = 0;
satrec.whichconst = whichconst # Python extension: remembers its consts
line = longstr1.rstrip()
try:
assert line.startswith('1 ')
satrec.satnum = int(line[2:7])
# classification = line[7] or 'U'
assert line[8] == ' '
# intldesg = line[9:17]
two_digit_year = int(line[18:20])
assert line[23] == '.'
satrec.epochdays = float(line[20:32])
assert line[32] == ' '
assert line[34] == '.'
satrec.ndot = float(line[33:43])
assert line[43] == ' '
satrec.nddot = float(line[44] + '.' + line[45:50])
nexp = int(line[50:52])
assert line[52] == ' '
satrec.bstar = float(line[53] + '.' + line[54:59])
ibexp = int(line[59:61])
assert line[61] == ' '
assert line[63] == ' '
# numb = int(line[62])
# elnum = int(line[64:68])
except (AssertionError, IndexError, ValueError):
raise ValueError(error_message.format(1, LINE1, line))
line = longstr2.rstrip()
try:
assert line.startswith('2 ')
satrec.satnum = int(line[2:7]) # TODO: check it matches line 1?
assert line[7] == ' '
assert line[11] == '.'
satrec.inclo = float(line[8:16])
assert line[16] == ' '
assert line[20] == '.'
satrec.nodeo = float(line[17:25])
assert line[25] == ' '
satrec.ecco = float('0.' + line[26:33].replace(' ', '0'))
assert line[33] == ' '
assert line[37] == '.'
satrec.argpo = float(line[34:42])
assert line[42] == ' '
assert line[46] == '.'
satrec.mo = float(line[43:51])
assert line[51] == ' '
satrec.no = float(line[52:63])
#revnum = line[63:68]
except (AssertionError, IndexError, ValueError):
raise ValueError(error_message.format(2, LINE2, line))
# ---- find no, ndot, nddot ----
satrec.no = satrec.no / xpdotp; # rad/min
satrec.nddot= satrec.nddot * pow(10.0, nexp);
satrec.bstar= satrec.bstar * pow(10.0, ibexp);
# ---- convert to sgp4 units ----
satrec.a = pow( satrec.no*tumin , (-2.0/3.0) );
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;
satrec.alta = satrec.a*(1.0 + satrec.ecco) - 1.0;
satrec.altp = satrec.a*(1.0 - satrec.ecco) - 1.0;
"""
// ----------------------------------------------------------------
// 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);
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.ecco, satrec.argpo, satrec.inclo, satrec.mo, satrec.no,
satrec.nodeo, satrec)
return satrec
def twoline2rv(longstr1, longstr2, whichconst, afspc_mode=False):
"""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 "afspc" mode, then set `afspc_mode` to `True`.
"""
opsmode = 'a' if afspc_mode else 'i'
deg2rad = pi / 180.0; # 0.0174532925199433
xpdotp = 1440.0 / (2.0 *pi); # 229.1831180523293
tumin = whichconst.tumin
satrec = Satellite()
satrec.error = 0;
satrec.whichconst = whichconst # Python extension: remembers its consts
line = longstr1.rstrip()
try:
assert line.startswith('1 ')
satrec.satnum = int(line[2:7])
# classification = line[7] or 'U'
assert line[8] == ' '
# intldesg = line[9:17]
two_digit_year = int(line[18:20])
assert line[23] == '.'
satrec.epochdays = float(line[20:32])
assert line[32] == ' '
assert line[34] == '.'
satrec.ndot = float(line[33:43])
assert line[43] == ' '
satrec.nddot = float(line[44] + '.' + line[45:50])
nexp = int(line[50:52])
assert line[52] == ' '
satrec.bstar = float(line[53] + '.' + line[54:59])
ibexp = int(line[59:61])
assert line[61] == ' '
assert line[63] == ' '
# numb = int(line[62])
# elnum = int(line[64:68])
except (AssertionError, IndexError, ValueError):
raise ValueError(error_message.format(1, LINE1, line))
line = longstr2.rstrip()
try:
assert line.startswith('2 ')
satrec.satnum = int(line[2:7]) # TODO: check it matches line 1?
assert line[7] == ' '
assert line[11] == '.'
satrec.inclo = float(line[8:16])
assert line[16] == ' '
assert line[20] == '.'
satrec.nodeo = float(line[17:25])
assert line[25] == ' '
satrec.ecco = float('0.' + line[26:33].replace(' ', '0'))
assert line[33] == ' '
assert line[37] == '.'
satrec.argpo = float(line[34:42])
assert line[42] == ' '
assert line[46] == '.'
satrec.mo = float(line[43:51])
assert line[51] == ' '
satrec.no = float(line[52:63])
#revnum = line[63:68]
except (AssertionError, IndexError, ValueError):
raise ValueError(error_message.format(2, LINE2, line))
# ---- find no, ndot, nddot ----
satrec.no = satrec.no / xpdotp; # rad/min
satrec.nddot= satrec.nddot * pow(10.0, nexp);
satrec.bstar= satrec.bstar * pow(10.0, ibexp);
# ---- convert to sgp4 units ----
satrec.a = pow( satrec.no*tumin , (-2.0/3.0) );
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;
satrec.alta = satrec.a*(1.0 + satrec.ecco) - 1.0;
satrec.altp = satrec.a*(1.0 - satrec.ecco) - 1.0;
"""
// ----------------------------------------------------------------
// 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);
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.ecco, satrec.argpo, satrec.inclo, satrec.mo, satrec.no,
satrec.nodeo, satrec)
print satrec
return satrec