def test_bad_tle_checksumx(self):
self.assertEqual(io.compute_checksum(good1), 3)
bad = good1[:68] + '7'
self.assertRaises(ValueError, io.verify_checksum, bad)
def export_tle(satrec):
"""Generate the TLE for a given `Satrec` object; returns two strings."""
# --------------------- Start generating line 1 ---------------------
# Build the list by appending successive items
pieces = ["1 "]
append = pieces.append
# Pad the `satnum` entry with zeros
if len(str(satrec.satnum)) <= 5:
append(str(satrec.satnum).zfill(5))
# Add classification code (use "U" if empty)
classification = getattr(satrec, 'classification', 'U')
append(classification.strip() or 'U')
append(' ')
# Add int'l designator and pad to 8 chars
intldesg = getattr(satrec, 'intldesg', '')
append('{0:8} '.format(intldesg))
# Add epoch year and days in YYDDD.DDDDDDDD format
epochyr = satrec.epochyr
# Undo non-standard 4-digit year for old satrec objects
epochyr %= 100
append(str(epochyr).zfill(2) + "{:012.8f}".format(satrec.epochdays) + " ")
# Add First Time Derivative of the Mean Motion (don't use "+")
append("{0: 8.8f}".format(satrec.ndot *
(_xpdotp * 1440.0)).replace("0", "", 1) + " ")
# Add Second Time Derivative of Mean Motion (don't use "+")
# Multiplication with 10 is a hack to get the exponent right
append("{0: 4.4e}".format(
(satrec.nddot * (_xpdotp * 1440.0 * 1440)) *
10).replace(".", "").replace("e+00", "-0").replace("e-0", "-") + " ")
# Add BSTAR
# Multiplication with 10 is a hack to get the exponent right
append("{0: 4.4e}".format(satrec.bstar * 10).replace(".", "").replace(
"e+00", "+0").replace("e-0", "-") + " ")
# Add Ephemeris Type and Element Number
ephtype = getattr(satrec, 'ephtype', 0)
elnum = getattr(satrec, 'elnum', 0)
append('{0} {1:4}'.format(ephtype, elnum))
# Join all the parts and add the Checksum
line1 = ''.join(pieces)
line1 += str(compute_checksum(line1))
# --------------------- Start generating line 2 ---------------------
# Reset the str array
pieces = ["2 "]
append = pieces.append
# Pad the `satnum` entry with zeros
if len(str(satrec.satnum)) <= 5:
append(str(satrec.satnum).zfill(5) + " ")
# Add the inclination (deg)
if not 0 <= satrec.inclo <= pi:
raise ValueError("Inclination must be between 0 and pi, got %r",
satrec.inclo)
append("{0:8.4f}".format(satrec.inclo / _deg2rad).rjust(8, " ") + " ")
# Add the RAAN (deg)
if not 0 <= satrec.nodeo <= 2 * pi:
raise ValueError("RAAN must be between 0 and 2 pi, got %r",
satrec.nodeo)
append("{0:8.4f}".format(satrec.nodeo / _deg2rad).rjust(8, " ") + " ")
# Add the eccentricity (delete the leading zero an decimal point)
append("{0:8.7f}".format(satrec.ecco).replace("0.", "") + " ")
# Add the Argument of Perigee (deg)
if not 0 <= satrec.argpo <= 2 * pi:
raise ValueError(
"Argument of Perigee must be between 0 and 2 pi, got %r",
satrec.argpo)
append("{0:8.4f}".format(satrec.argpo / _deg2rad).rjust(8, " ") + " ")
# Add the Mean Anomaly (deg)
if not 0 <= satrec.mo <= 2 * pi:
raise ValueError("Mean Anomaly must be between 0 and 2 pi, got %r",
satrec.mo)
append("{0:8.4f}".format(satrec.mo / _deg2rad).rjust(8, " ") + " ")
# Add the Mean Motion (revs/day)
append("{0:11.8f}".format(satrec.no_kozai * _xpdotp).rjust(8, " "))
# Add the rev number at epoch
append(str(satrec.revnum).rjust(5))
# Join all the parts and add the Checksum
line2 = ''.join(pieces)
line2 += str(compute_checksum(line2))
return line1, line2
def test_good_tle_checksum(self):
for line, expected in (good1, 3), (good2, 7):
self.assertEqual(io.compute_checksum(line), expected)
self.assertEqual(io.fix_checksum(line[:68]), line)
io.verify_checksum(line)
def test_good_tle_checksum():
for line in LINE1, LINE2:
checksum = int(line[-1])
assertEqual(io.compute_checksum(line), checksum)
assertEqual(io.fix_checksum(line[:68]), line)
io.verify_checksum(line)
def export_tle(satrec):
"""Generate the TLE for a given `Satrec` object; returns two strings."""
# --------------------- Start generating line 1 ---------------------
# Build the list by appending successive items
pieces = ["1 "]
append = pieces.append
# Pad the `satnum` entry with zeros
if len(str(satrec.satnum)) <= 5:
append(str(satrec.satnum).zfill(5))
# Add classification code (use "U" if empty)
append((satrec.classification.strip() or "U") + " ")
# Add int'l designator and pad to 8 chars
append(satrec.intldesg.ljust(8, " ") + " ")
# Add epoch year and days in YYDDD.DDDDDDDD format
append(
str(satrec.epochyr).zfill(2) + "{:012.8f}".format(satrec.epochdays) +
" ")
# Add First Time Derivative of the Mean Motion (don't use "+")
append("{0: 8.8f}".format(satrec.ndot *
(_xpdotp * 1440.0)).replace("0", "", 1) + " ")
# Add Second Time Derivative of Mean Motion (don't use "+")
# Multiplication with 10 is a hack to get the exponent right
append("{0: 4.4e}".format(
(satrec.nddot * (_xpdotp * 1440.0 * 1440)) *
10).replace(".", "").replace("e+00", "-0").replace("e-0", "-") + " ")
# Add BSTAR
# Multiplication with 10 is a hack to get the exponent right
append("{0: 4.4e}".format(satrec.bstar * 10).replace(".", "").replace(
"e+00", "+0").replace("e-0", "-") + " ")
# Add Ephemeris Type and Element Number
append("{} ".format(satrec.ephtype) + str(satrec.elnum).rjust(4, " "))
# Join all the parts and add the Checksum
line1 = ''.join(pieces)
line1 += str(compute_checksum(line1))
# --------------------- Start generating line 2 ---------------------
# Reset the str array
pieces = ["2 "]
append = pieces.append
# Pad the `satnum` entry with zeros
if len(str(satrec.satnum)) <= 5:
append(str(satrec.satnum).zfill(5) + " ")
# Add the inclination (deg)
append("{0:8.4f}".format(satrec.inclo / _deg2rad).rjust(8, " ") + " ")
# Add the RAAN (deg)
append("{0:8.4f}".format(satrec.nodeo / _deg2rad).rjust(8, " ") + " ")
# Add the eccentricity (delete the leading zero an decimal point)
append("{0:8.7f}".format(satrec.ecco).replace("0.", "") + " ")
# Add the Argument of Perigee (deg)
append("{0:8.4f}".format(satrec.argpo / _deg2rad).rjust(8, " ") + " ")
# Add the Mean Anomaly (deg)
append("{0:8.4f}".format(satrec.mo / _deg2rad).rjust(8, " ") + " ")
# Add the Mean Motion (revs/day)
append("{0:11.8f}".format(satrec.no_kozai * _xpdotp).rjust(8, " "))
# Add the rev number at epoch
append(str(satrec.revnum).rjust(5))
# Join all the parts and add the Checksum
line2 = ''.join(pieces)
line2 += str(compute_checksum(line2))
return line1, line2
def test_bad_tle_checksumx(self):
self.assertEqual(io.compute_checksum(good1), 3)
bad = good1[:68] + '7'
self.assertRaises(ValueError, io.verify_checksum, bad)
def test_good_tle_checksum(self):
for line, expected in (good1, 3), (good2, 7):
self.assertEqual(io.compute_checksum(line), expected)
self.assertEqual(io.fix_checksum(line[:68]), line)
io.verify_checksum(line)
