def test_writeRinex3Obs(self):
"""Test reading and writing back out a rinex obs file"""
header, data = gpstk.readRinex3Obs(args.input_dir + "/arlm200a.15o",
strict=True)
# Now let's write it all back to a different file
gpstk.writeRinex3Obs(args.output_dir + '/swig-arlm200a.15o', header,
data)
def test_stream(self):
header, data = gpstk.readRinex3Obs('rinex3obs_data.txt', strict=True)
self.assertEqual(0L, header.numSVs)
self.assertEqual('NATIONAL IMAGERY AND MAPPING AGENCY', header.agency)
self.assertEqual(120, len(data))
dataPoint = data[0]
datum = dataPoint.getObs(gpstk.SatID(4), header.getObsIndex("C1"))
self.assertAlmostEqual(24236698.057, datum.data)
self.assertEqual(0, dataPoint.clockOffset)
expectedTime = gpstk.CommonTime()
expectedTime.set(2453167)
expectedTime.setTimeSystem(gpstk.TimeSystem(gpstk.TimeSystem.GPS))
self.assertEqual(expectedTime, dataPoint.time)
def test_stream(self):
header, data = gpstk.readRinex3Obs('rinex3obs_data.txt', strict=True)
self.assertEqual(0L, header.numSVs)
self.assertEqual('NATIONAL IMAGERY AND MAPPING AGENCY', header.agency)
self.assertEqual(120, len(data))
dataPoint = data[0]
datum = dataPoint.getObs(gpstk.SatID(4), header.getObsIndex("C1"))
self.assertAlmostEqual(24236698.057, datum.data)
self.assertEqual(0, dataPoint.clockOffset)
expectedTime = gpstk.CommonTime()
expectedTime.set(2453167)
expectedTime.setTimeSystem(gpstk.TimeSystem(gpstk.TimeSystem.GPS))
self.assertEqual(expectedTime, dataPoint.time)
def tweakInternalHeaderState(rinex_obs_header):
'''
There's a slight defect in the Rinex3ObsHeader object which causes it
to only be in the correct state for full file writing if the header
has been read from a file.
This method is a hack to write the fully-built header (no data) to a file and
read it back in.
That way the header can be used to write another file which _does_ have data.
'''
temp_file = tempfile.NamedTemporaryFile().name
gpstk.writeRinex3Obs(temp_file, rinex_obs_header, [])
tweaked_header, _ = gpstk.readRinex3Obs(temp_file)
os.remove(temp_file)
return tweaked_header
def tweakInternalHeaderState(rinex_obs_header):
'''
There's a slight defect in the Rinex3ObsHeader object which causes it
to only be in the correct state for full file writing if the header
has been read from a file.
This method is a hack to write the fully-built header (no data) to a file and
read it back in.
That way the header can be used to write another file which _does_ have data.
'''
temp_file = tempfile.NamedTemporaryFile().name
gpstk.writeRinex3Obs(temp_file, rinex_obs_header, [])
tweaked_header, _ = gpstk.readRinex3Obs(temp_file)
os.remove(temp_file)
return tweaked_header
def test_readRinex3Obs(self):
"""Test reading entire rinex obs file and spot check the data"""
header, data = gpstk.readRinex3Obs( args.input_dir+"/arlm200a.15o", strict=True)
# Find the earliest and latest observations
# function for how to compare Rinex3ObsData objects for min/max functions:
timeFunction = lambda self: self.time
earliest = min(data, key=timeFunction)
latest = max(data, key=timeFunction)
self.assertEqual(
gpstk.CivilTime(2015, 7, 19, 0, 0, 0, gpstk.TimeSystem(gpstk.TimeSystem.GPS)),
gpstk.CivilTime(earliest.time))
self.assertEqual(
gpstk.CivilTime(2015, 7, 19, 0, 59, 30, gpstk.TimeSystem(gpstk.TimeSystem.GPS)),
gpstk.CivilTime(latest.time))
def main():
# Read in the rinex data
header, data = gpstk.readRinex3Obs('rinex3obs_data.txt', strict=True)
# Let's pretend we want to change something in the header
# (otherwise this would be a two-line example!)
header.receiverOffset = 47
# Now let's find the earliest and latest observations
# function for how to compare Rinex3ObsData objects for min/max functions:
timeFunction = lambda self: self.time
earliest = min(data, key=timeFunction)
latest = max(data, key=timeFunction)
print 'Earliest time found:', gpstk.CivilTime(earliest.time)
print 'Latest time found: ', gpstk.CivilTime(latest.time)
# Now let's write it all back to a different file
gpstk.writeRinex3Obs('rinex3obs_data.txt.new', header, data)
def main():
# Read in the rinex data
header, data = gpstk.readRinex3Obs('rinex3obs_data.txt', strict=True)
# Let's pretend we want to change something in the header
# (otherwise this would be a two-line example!)
header.receiverOffset = 47
# Now let's find the earliest and latest observations
# function for how to compare Rinex3ObsData objects for min/max functions:
timeFunction = lambda self: self.time
earliest = min(data, key=timeFunction)
latest = max(data, key=timeFunction)
print 'Earliest time found:', gpstk.CivilTime(earliest.time)
print 'Latest time found: ', gpstk.CivilTime(latest.time)
# Now let's write it all back to a different file
gpstk.writeRinex3Obs('rinex3obs_data.txt.new', header, data)
def test_readRinex3Obs(self):
"""Test reading entire rinex obs file and spot check the data"""
header, data = gpstk.readRinex3Obs(args.input_dir + "/arlm200a.15o",
strict=True)
# Find the earliest and latest observations
# function for how to compare Rinex3ObsData objects for min/max functions:
timeFunction = lambda self: self.time
earliest = min(data, key=timeFunction)
latest = max(data, key=timeFunction)
self.assertEqual(
gpstk.CivilTime(2015, 7, 19, 0, 0, 0,
gpstk.TimeSystem(gpstk.TimeSystem.GPS)),
gpstk.CivilTime(earliest.time))
self.assertEqual(
gpstk.CivilTime(2015, 7, 19, 0, 59, 30,
gpstk.TimeSystem(gpstk.TimeSystem.GPS)),
gpstk.CivilTime(latest.time))
def main():
parser = argparse.ArgumentParser()
parser.add_argument('rinex3obs_filename')
args = parser.parse_args()
user_input = raw_input(
'Name your PRN of interest, by number: 1 through 32: ')
int_prn = int(user_input)
try:
print('Reading {}'.format(args.rinex3obs_filename))
header, data = gpstk.readRinex3Obs(
args.rinex3obs_filename) # read in everything
print(header)
# Now we loop through all the epochs and process the data for each one
for d in data:
# Let's use the CivilTime class to print an easy to understand time:
civtime = gpstk.CivilTime(d.time)
print(civtime, )
# Make a GPSTk SatID for the user's PRN so we can search for it
prn = gpstk.RinexSatID(int_prn, gpstk.SatID.systemGPS)
# Check if the PRN is in view (by searching for it)
if d.obs.find(prn) == d.obs.end():
print('PRN {} not in view'.format(int_prn))
else:
P1 = d.getObs(prn, "P1", header).data
P2 = d.getObs(prn, "P2", header).data
L1 = d.getObs(prn, "L1", header).data
mu = P1 - L1 * (C_MPS /
L1_FREQ_GPS) - 2 * (P1 - P2) / (1 - GAMMA_GPS)
print('PRN {} biased multipath {}'.format(int_prn, mu))
# We can catch any custom gpstk exception like this:
except gpstk.Exception as e:
print(e)
def main():
parser = argparse.ArgumentParser()
parser.add_argument('rinex3obs_filename')
args = parser.parse_args()
user_input = raw_input('Name your PRN of interest, by number: 1 through 32: ')
int_prn = int(user_input)
try:
print 'Reading ' + args.rinex3obs_filename + '.'
header, data = gpstk.readRinex3Obs(args.rinex3obs_filename) # read in everything
print header
# Now we loop through all the epochs and process the data for each one
for d in data:
# Let's use the CivilTime class to print an easy to understand time:
civtime = gpstk.CivilTime(d.time)
print civtime,
# Make a GPSTk SatID for the user's PRN so we can search for it
prn = gpstk.RinexSatID(int_prn, gpstk.SatID.systemGPS)
# Check if the PRN is in view (by searching for it)
if d.obs.find(prn) == d.obs.end():
print 'PRN', int_prn, 'not in view'
else:
P1 = d.getObs(prn, "P1", header).data
P2 = d.getObs(prn, "P2", header).data
L1 = d.getObs(prn, "L1", header).data
mu = P1 - L1*(C_MPS/L1_FREQ_GPS) - 2*(P1-P2)/(1-GAMMA_GPS)
print 'PRN', int_prn, 'biased multipath', mu
# We can catch any custom gpstk exception like this:
except gpstk.Exception as e:
print e
def rinex_to_dataframe(obsfile, navfile):
c = 299792458.
#observation_types=["P1", "P2", "L1", "L2"]
observation_types = ["C1", "P2", "L1", "L2"]
obsHeader, obsData = gpstk.readRinex3Obs(obsfile)
navHeader, navData = gpstk.readRinex3Nav(navfile)
# setup ephemeris store to look for satellite positions
bcestore = gpstk.GPSEphemerisStore()
for navDataObj in navData:
ephem = navDataObj.toGPSEphemeris()
bcestore.addEphemeris(ephem)
bcestore.SearchNear()
navData.close()
rec_pos = [
obsHeader.antennaPosition[0], obsHeader.antennaPosition[1],
obsHeader.antennaPosition[2]
]
requested_obstypes = observation_types
obsidxs = []
obstypes = []
obsdefs = np.array([i for i in obsHeader.R2ObsTypes])
for i in requested_obstypes:
w = np.where(obsdefs == i)[0]
if len(w) != 0:
obsidxs.append(w[0])
obstypes.append(i)
else:
print("WARNING! observation `" + i + "` no present in file")
obsidxs, obstypes
print obsdefs #que tipos hay
r = []
for obsObject in obsData:
prnlist = []
obsdict = {}
prnspos = []
prns_clockbias = []
prns_relcorr = []
prnselev = []
prnsaz = []
for i in obstypes:
obsdict[i] = []
gpsTime = gpstk.GPSWeekSecond(obsObject.time)
for satID, datumList in obsObject.obs.iteritems():
if satID.system == satID.systemGPS:
prnlist.append("".join(str(satID).split()))
try:
eph = bcestore.findEphemeris(satID, obsObject.time)
except:
print "no encontrada!"
for i in range(len(obsidxs)):
obsdict[obstypes[i]].append(
obsObject.getObs(satID, obsidxs[i]).data)
P1 = obsObject.getObs(satID, obsidxs[0]).data
svTime = obsObject.time - P1 / c
svXvt = eph.svXvt(svTime)
svTime += -svXvt.getClockBias() + svXvt.getRelativityCorr()
svXvt = eph.svXvt(svTime)
prnspos.append([svXvt.x[0], svXvt.x[1], svXvt.x[2]])
prns_clockbias.append(svXvt.getClockBias())
prns_relcorr.append(svXvt.getRelativityCorr())
prnselev.append(
obsHeader.antennaPosition.elvAngle(svXvt.getPos()))
prnsaz.append(obsHeader.antennaPosition.azAngle(
svXvt.getPos()))
correct_sod = np.round(
gpstk.YDSTime(obsObject.time).sod / 30.0) * 30 #mod 30s
r.append([
gpsTime.getWeek(),
gpsTime.getSOW(), correct_sod,
np.array(prnlist),
np.array(prnspos),
np.array(prns_clockbias),
np.array(prns_relcorr),
np.array(prnselev),
np.array(prnsaz)
] + [np.array(obsdict[i]) for i in obstypes])
names = [
"gps_week", "gps_sow", "tod", "prns", "prns_pos", "prns_clockbias",
"prns_relcorr", "prns_elev", "prns_az"
] + obstypes
r = pd.DataFrame(r, columns=names)
obsData.close()
return r, bcestore, np.array(rec_pos)
def rinex_to_dataframe(obsfile, navfile):
c = 299792458.
observation_types=["P1", "P2", "L1", "L2"]
obsHeader, obsData = gpstk.readRinex3Obs(obsfile)
navHeader, navData = gpstk.readRinex3Nav(navfile)
# setup ephemeris store to look for satellite positions
bcestore = gpstk.GPSEphemerisStore()
for navDataObj in navData:
ephem = navDataObj.toGPSEphemeris()
bcestore.addEphemeris(ephem)
bcestore.SearchNear()
navData.close()
rec_pos = [obsHeader.antennaPosition[0], obsHeader.antennaPosition[1], obsHeader.antennaPosition[2]]
requested_obstypes = observation_types
obsidxs = []
obstypes = []
obsdefs = np.array([i for i in obsHeader.R2ObsTypes])
for i in requested_obstypes:
w = np.where(obsdefs==i)[0]
if len(w)!=0:
obsidxs.append(w[0])
obstypes.append(i)
else:
print ("WARNING! observation `"+i+"` no present in file")
obsidxs, obstypes
r = []
for obsObject in obsData:
prnlist = []
obsdict = {}
prnspos = []
prns_clockbias = []
prns_relcorr = []
prnselev = []
prnsaz = []
for i in obstypes:
obsdict[i]=[]
gpsTime = gpstk.GPSWeekSecond(obsObject.time)
for satID, datumList in obsObject.obs.iteritems():
if satID.system == satID.systemGPS:
prnlist.append("".join(str(satID).split()))
eph = bcestore.findEphemeris(satID, obsObject.time)
for i in range(len(obsidxs)):
obsdict[obstypes[i]].append(obsObject.getObs(satID, obsidxs[i]).data)
P1 = obsObject.getObs(satID, obsidxs[0]).data
svTime = obsObject.time - P1/c
svXvt = eph.svXvt(svTime)
svTime += - svXvt.getClockBias() + svXvt.getRelativityCorr()
svXvt = eph.svXvt(svTime)
prnspos.append([svXvt.x[0], svXvt.x[1], svXvt.x[2]])
prns_clockbias.append(svXvt.getClockBias())
prns_relcorr.append(svXvt.getRelativityCorr())
prnselev.append(obsHeader.antennaPosition.elvAngle(svXvt.getPos()))
prnsaz.append(obsHeader.antennaPosition.azAngle(svXvt.getPos()))
r.append([gpsTime.getWeek(), gpsTime.getSOW(), np.array(prnlist), np.array(prnspos), np.array(prns_clockbias), np.array(prns_relcorr), np.array(prnselev), np.array(prnsaz)] + [np.array(obsdict[i]) for i in obstypes])
names=["gps_week", "gps_sow", "prns", "prns_pos", "prns_clockbias", "prns_relcorr", "prns_elev", "prns_az"] + obstypes
r = pd.DataFrame(r, columns=names)
obsData.close()
return r, bcestore, np.array(rec_pos)
def test_stream_lazy(self):
header, gen = gpstk.readRinex3Obs(
gpstk.data.full_path('rinex2obs_data.txt'), strict=False)
data = list(gen)
self.assertEqual(120, len(data))
def getdata(nfile, ofile, strsat=None): # one week data
f1, f2 = gpstk.L1_FREQ_GPS, gpstk.L2_FREQ_GPS
alfa = 1.0 / ((f1 ** 2 / f2 ** 2) - 1)
t = [] # observation epoch on code and phase
Iphase, Icode, IPPS = {}, {}, {} # dicc: key=time observer; values=iono delay and IPP
VTECphase, VTECcode, ELEV = {}, {}, {}
PhaseL1, PhaseL2 = {}, {}
CodeL1, CodeL2 = {}, {}
oheader, odata = gpstk.readRinex3Obs(ofile, strict=True)
nheader, ndata = gpstk.readRinex3Nav(nfile)
bcestore = gpstk.GPSEphemerisStore()
for ndato in ndata:
ephem = ndato.toGPSEphemeris()
bcestore.addEphemeris(ephem)
bcestore.SearchNear()
for observation in odata:
sats = [satID for satID, datumList in observation.obs.iteritems() if str(satID).split()[0] == "GPS"]
obs_types = np.array([i for i in oheader.R2ObsTypes])
if "C1" and "P2" and "L1" and "L2" in obs_types:
for sat in sats:
if str(sat) == strsat: # Return for a specific satellite
eph = bcestore.findEphemeris(sat, observation.time)
Tgd = eph.Tgd
sat_pos = eph.svXvt(observation.time)
rec_pos = gpstk.Position(
oheader.antennaPosition[0], oheader.antennaPosition[1], oheader.antennaPosition[2]
).asECEF()
elev = oheader.antennaPosition.elvAngle(sat_pos.x)
azim = oheader.antennaPosition.azAngle(sat_pos.x)
time = observation.time
R = 6.378e6 # earth radius
mapp = 1 / np.cos(np.arcsin(R / (R + 350000)) * np.sin(elev))
IPP = rec_pos.getIonosphericPiercePoint(elev, azim, 350000).asECEF()
t.append(np.trunc(gpstk.YDSTime(time).sod))
if (
np.size(np.where(obs_types == "C1")) > 0
and np.size(np.where(obs_types == "P2")) > 0
and np.size(np.where(obs_types == "L1")) > 0
and np.size(np.where(obs_types == "L2")) > 0
):
C1_idx = np.where(obs_types == "C1")[0][0]
P2_idx = np.where(obs_types == "P2")[0][0]
R1 = observation.getObs(sat, C1_idx).data
R2 = observation.getObs(sat, P2_idx).data
L1_idx = np.where(obs_types == "L1")[0][0]
L2_idx = np.where(obs_types == "L2")[0][0]
L1 = observation.getObs(sat, L1_idx).data * gpstk.L1_WAVELENGTH_GPS
L2 = observation.getObs(sat, L2_idx).data * gpstk.L2_WAVELENGTH_GPS
if (
R2 < 3e7 and R1 < 3e7 and L2 < 3e7 and L1 < 3e7
): # Distances should be in order of 1e7 meters, more than that is considered an error
iono_delay_c = alfa * (R2 - R1)
iono_delay_p = alfa * (L1 - L2)
vtec_C = iono_delay_c / mapp
vtec_P = iono_delay_p / mapp
VTECcode[np.trunc(gpstk.YDSTime(time).sod)] = vtec_C
VTECphase[np.trunc(gpstk.YDSTime(time).sod)] = vtec_P
Icode[np.trunc(gpstk.YDSTime(time).sod)] = iono_delay_c
Iphase[np.trunc(gpstk.YDSTime(time).sod)] = iono_delay_p
ELEV[np.trunc(gpstk.YDSTime(time).sod)] = elev
IPPS[np.trunc(gpstk.YDSTime(time).sod)] = IPP
PhaseL1[np.trunc(gpstk.YDSTime(time).sod)] = L1
PhaseL2[np.trunc(gpstk.YDSTime(time).sod)] = L2
CodeL1[np.trunc(gpstk.YDSTime(time).sod)] = R1
CodeL2[np.trunc(gpstk.YDSTime(time).sod)] = R2
# stec=(iono_delay_p*f1**2)/(-40.3) #STEC delay on phase [mm]
# vtec=stec/mapp #vertical delay!
else:
print "Needs both L1 and L2 frequencies to compute delay"
break
return t, Icode, Iphase, VTECphase, ELEV, IPPS, PhaseL1, PhaseL2, CodeL1, CodeL2, Tgd
def process(input_file, output_file):
try:
print 'Reading {}.'.format(input_file)
header, data = gpstk.readRinex3Obs(input_file) # read in everything
#print header
new_header = gpstk.Rinex3ObsHeader()
# Initially, valid = 0L, but other values get masked into it.
new_header.version = header.version
new_header.fileType = header.fileType
new_header.valid = new_header.valid | gpstk.Rinex3ObsHeader.validVersion
new_header.fileProgram = header.fileProgram
new_header.date = header.date
new_header.fileAgency = header.fileAgency
new_header.valid = new_header.valid | gpstk.Rinex3ObsHeader.validRunBy
new_header.markerName = header.markerName
new_header.valid = new_header.valid | gpstk.Rinex3ObsHeader.validMarkerName
new_header.observer = header.observer
new_header.agency = header.agency
new_header.valid = new_header.valid | gpstk.Rinex3ObsHeader.validObserver
new_header.recNo = header.recNo
new_header.recType = header.recType
new_header.recVers = header.recVers
new_header.valid = new_header.valid | gpstk.Rinex3ObsHeader.validReceiver
new_header.antNo = header.antNo
new_header.antType = header.antType
new_header.valid = new_header.valid | gpstk.Rinex3ObsHeader.validAntennaType
newAntPosition = gpstk.Triple(header.antennaPosition[0],header.antennaPosition[1],header.antennaPosition[2])
new_header.antennaPosition = newAntPosition
new_header.valid = new_header.valid | gpstk.Rinex3ObsHeader.validAntennaPosition
newAntDelta = gpstk.Triple(header.antennaDeltaHEN[0],header.antennaDeltaHEN[1],header.antennaDeltaHEN[2])
new_header.antennaDeltaHEN = newAntDelta
new_header.valid = new_header.valid | gpstk.Rinex3ObsHeader.validAntennaDeltaHEN
# This is kind of odd. The Rinex3ObsHeader can handle both V3 and V2
# formatted files. The two versions handle observation types differently.
# - The first structure "mapObsTypes" holds the V3 definitions in a
# "dictionary of lists" (or "map of vectors" in c++)
# - The second structure "R2ObsTypes" holds the V2 definitions and is
# stored as list of strings (or Vector of Strings in c++)
# It's not clear whether either or both are necessary to write a file.
# It DOES seem to be clear that both will be available after reading a file.
for rinObsType in header.mapObsTypes:
#print "Found obs-type:{}".format(rinObsType)
newObsIds = []
for rinObsId in header.mapObsTypes[rinObsType]:
#print "Found obs-id:{}".format(str(rinObsId))
#print " --type={} code={} band={}".format(rinObsId.type, rinObsId.code, rinObsId.band)
newObsId = gpstk.RinexObsID(str(rinObsId))
newObsIds.append(newObsId)
new_header.mapObsTypes[rinObsType] = tuple(newObsIds)
new_header.valid = new_header.valid | gpstk.Rinex3ObsHeader.validNumObs
for rin_obs_id in header.R2ObsTypes:
#print "Found obs-id:{}".format(rin_obs_id)
new_header.R2ObsTypes.append(rin_obs_id)
new_header.valid = new_header.valid | gpstk.Rinex3ObsHeader.validNumObs
# This creates a new CivilTime object that we can populate
new_header.firstObs = gpstk.CivilTime()
new_header.firstObs.year = header.firstObs.year
new_header.firstObs.month = header.firstObs.month
new_header.firstObs.day = header.firstObs.day
new_header.firstObs.hour = header.firstObs.hour
new_header.firstObs.minute = header.firstObs.minute
new_header.firstObs.second = header.firstObs.second
new_header.valid = new_header.valid | gpstk.Rinex3ObsHeader.validFirstTime
new_header.markerNumber = header.markerNumber
new_header.valid = new_header.valid | gpstk.Rinex3ObsHeader.validMarkerNumber
new_header.interval = header.interval
new_header.valid = new_header.valid | gpstk.Rinex3ObsHeader.validInterval
#####
# Unfortunately, sigStrengthUnit is tied to the wavelengthFactor property,
# We cannot set the latter due to a missing SWIG Python adapter, and
# because the same "validity flag" governs both, we can't output
# sigStrengthUnit without inadvertently outputting a bogus wavelengthFactor.
#####
#new_header.wavelengthFactor = header.wavelengthFactor
#new_header.sigStrengthUnit = header.sigStrengthUnit
#new_header.valid = new_header.valid | gpstk.Rinex3ObsHeader.validSigStrengthUnit
for comment in header.commentList:
new_header.commentList.append(comment)
new_header.valid = new_header.valid | gpstk.Rinex3ObsHeader.validComment
new_header.validEoH = True
# This method is a huge hack to get around a problem in the Rinex3ObsData
# writer. See the method for details.
new_header = tweakInternalHeaderState(new_header)
#print new_header
processed_data = []
# Now we loop through all the epochs and process the data for each one
for d in data:
# This creates a new CommonTime object with the system set to GPS.
timec = gpstk.CommonTime(gpstk.TimeSystem(gpstk.TimeSystem.GPS))
# This creates a new CommonTime object with the system set to GPS.
mjd = int(d.time.getDays())
sod = float(d.time.getSecondOfDay())
timec.set(mjd, sod, gpstk.TimeSystem(gpstk.TimeSystem.GPS))
# Assign values to a new Rinex Obs Data object
nd = gpstk.Rinex3ObsData()
nd.time = timec
nd.auxHeader = d.auxHeader
nd.clockOffset = d.clockOffset
nd.epochFlag= d.epochFlag
nd.numSVs = d.numSVs
for satkey in d.obs.keys():
newSatKey = gpstk.RinexSatID(satkey.toString())
satObss = d.obs[newSatKey]
# satObss is a tuple of RinexDatum
newSatObss = []
for satObs in satObss:
#print "{} {} {} {}".format(satkey.toString(), satObs.data, satObs.lli, satObs.ssi)
newSatObs = gpstk.RinexDatum()
newSatObs.data = satObs.data
newSatObs.lli = satObs.lli
newSatObs.ssi = satObs.ssi
newSatObss.append(newSatObs)
nd.obs[newSatKey] = tuple(newSatObss)
#print "O{}".format(d)
#print "S{}".format(nd)
processed_data.append(nd)
gpstk.writeRinex3Obs(output_file, new_header, processed_data)
print "Wrote output file: {}".format(output_file)
# We can catch any custom gpstk exception like this:
except gpstk.Exception as e:
print e
"""
1. Extract pseudorange obs
2. compute biased multipath observation.
"""
from __future__ import print_function
from gpstk import C_MPS, GAMMA_GPS, L1_FREQ_GPS
import gpstk
rfn = gpstk.getPathData() + '/test_input_rinex2_obs_RinexObsFile.06o'
# Make a GPSTk SatID used to find a specific satellite in the data
svid = gpstk.RinexSatID(5, gpstk.SatID.systemGPS)
try:
header, data = gpstk.readRinex3Obs(rfn, strict=True)
print(header)
# Loop through all the epochs and process the data for each one
for d in data:
# Note that d is now a Rinex3ObsData
# Check if the PRN is in view (by searching for it)
if d.obs.find(svid) == d.obs.end():
print(gpstk.CivilTime(d.time), 'svid', svid, 'not in view')
else:
P1 = d.getObs(svid, "C1W", header).data
P2 = d.getObs(svid, "C2W", header).data
L1 = d.getObs(svid, "L1C", header).data
mu = P1 - L1 * (C_MPS / L1_FREQ_GPS) - 2 * (P1 - P2) / (1 - GAMMA_GPS)
print(gpstk.CivilTime(d.time), svid, 'biased multipath', mu)
python ./example5.py rinex2obs_data.txt
"""
import argparse
import gpstk
parser = argparse.ArgumentParser()
parser.add_argument('rinex2obs_filename')
args = parser.parse_args()
try:
print 'Reading ' + args.rinex2obs_filename + '.'
# read in header and get a generator for the data
header, data = gpstk.readRinex3Obs(args.rinex2obs_filename)
print header
for d in data:
civtime = gpstk.CivilTime(d.time)
print civtime
oe = gpstk.ObsEpoch()
oe.time = d.time
for sv in d.obs.keys():
print sv,
epoch = d.obs[sv]
soe = gpstk.SvObsEpoch()
soe.svid = sv
for i in range(len(epoch)):
rinex2_obs_type = header.R2ObsTypes[i]
oid = header.mapObsTypes['G'][i]
#!/usr/bin/env python """ An example of generating new rinex file (both v2,11 and v3.02. First an existing v2.11 file is read in just so we don't have to make up all the data that goes into the new files. """ import gpstk ifn = gpstk.getPathData() + '/test_input_rinex2_obs_RinexObsFile.06o' header, data = gpstk.readRinex3Obs(ifn, strict=True) new_header = gpstk.Rinex3ObsHeader() new_header.fileType = header.fileType new_header.fileProgram = header.fileProgram new_header.date = header.date new_header.fileAgency = header.fileAgency new_header.valid = new_header.valid | gpstk.Rinex3ObsHeader.validRunBy new_header.markerName = header.markerName new_header.valid = new_header.valid | gpstk.Rinex3ObsHeader.validMarkerName new_header.observer = header.observer new_header.agency = header.agency new_header.valid = new_header.valid | gpstk.Rinex3ObsHeader.validObserver new_header.recNo = header.recNo new_header.recType = header.recType new_header.recVers = header.recVers
#!/usr/bin/env python
"""
An example of how to walk a RINEX data set and use SatID and ObsID,
building an obsEpochMap of the data along the way.
"""
from __future__ import print_function
import gpstk
fn = gpstk.getPathData() + '/arlm200z.15o'
# read in header and get a generator for the data
header, data = gpstk.readRinex3Obs(fn)
print(header)
oem = gpstk.ObsEpochMap()
for d in data:
print(gpstk.CivilTime(d.time))
oe = gpstk.ObsEpoch()
oe.time = d.time
for sv in list(d.obs.keys()):
# sv is an SatID object
print(sv, end=' ')
epoch = d.obs[sv]
soe = gpstk.SvObsEpoch()
soe.svid = sv
for i in range(len(epoch)):
rinex2_obs_type = header.R2ObsTypes[i]
oid = header.mapObsTypes['G'][i]
print("{}({})={}".format(oid, rinex2_obs_type, epoch[i].data),
end=' ')
soe[oid] = epoch[i].data
def test_writeRinex3Obs(self):
"""Test reading and writing back out a rinex obs file"""
header, data = gpstk.readRinex3Obs( args.input_dir+"/arlm200a.15o", strict=True)
# Now let's write it all back to a different file
gpstk.writeRinex3Obs( args.output_dir+'/swig-arlm200a.15o', header, data)
def test_stream_lazy(self):
header, gen = gpstk.readRinex3Obs('rinex3obs_data.txt', strict=False)
data = list(gen)
self.assertEqual(120, len(data))
#!/usr/bin/env python
"""
An example of how to walk a RINEX data set and use SatID and ObsID,
building an obsEpochMap of the data along the way.
"""
import gpstk
fn = gpstk.getPathData() + '/arlm200z.15o'
# read in header and get a generator for the data
header, data = gpstk.readRinex3Obs(fn)
print header
oem = gpstk.ObsEpochMap()
for d in data:
print gpstk.CivilTime(d.time)
oe=gpstk.ObsEpoch()
oe.time = d.time
for sv in d.obs.keys():
# sv is an SatID object
print sv,
epoch = d.obs[sv]
soe = gpstk.SvObsEpoch()
soe.svid = sv
for i in range(len(epoch)):
rinex2_obs_type = header.R2ObsTypes[i]
oid = header.mapObsTypes['G'][i]
print "{}({})={}".format(str(oid), rinex2_obs_type, epoch[i].data),
soe[oid] = epoch[i].data
def process(input_file, output_file):
try:
print 'Reading {}.'.format(input_file)
header, data = gpstk.readRinex3Obs(input_file) # read in everything
#print header
new_header = gpstk.Rinex3ObsHeader()
# Initially, valid = 0L, but other values get masked into it.
new_header.version = header.version
new_header.fileType = header.fileType
new_header.valid = new_header.valid | gpstk.Rinex3ObsHeader.validVersion
new_header.fileProgram = header.fileProgram
new_header.date = header.date
new_header.fileAgency = header.fileAgency
new_header.valid = new_header.valid | gpstk.Rinex3ObsHeader.validRunBy
new_header.markerName = header.markerName
new_header.valid = new_header.valid | gpstk.Rinex3ObsHeader.validMarkerName
new_header.observer = header.observer
new_header.agency = header.agency
new_header.valid = new_header.valid | gpstk.Rinex3ObsHeader.validObserver
new_header.recNo = header.recNo
new_header.recType = header.recType
new_header.recVers = header.recVers
new_header.valid = new_header.valid | gpstk.Rinex3ObsHeader.validReceiver
new_header.antNo = header.antNo
new_header.antType = header.antType
new_header.valid = new_header.valid | gpstk.Rinex3ObsHeader.validAntennaType
newAntPosition = gpstk.Triple(header.antennaPosition[0],
header.antennaPosition[1],
header.antennaPosition[2])
new_header.antennaPosition = newAntPosition
new_header.valid = new_header.valid | gpstk.Rinex3ObsHeader.validAntennaPosition
newAntDelta = gpstk.Triple(header.antennaDeltaHEN[0],
header.antennaDeltaHEN[1],
header.antennaDeltaHEN[2])
new_header.antennaDeltaHEN = newAntDelta
new_header.valid = new_header.valid | gpstk.Rinex3ObsHeader.validAntennaDeltaHEN
# This is kind of odd. The Rinex3ObsHeader can handle both V3 and V2
# formatted files. The two versions handle observation types differently.
# - The first structure "mapObsTypes" holds the V3 definitions in a
# "dictionary of lists" (or "map of vectors" in c++)
# - The second structure "R2ObsTypes" holds the V2 definitions and is
# stored as list of strings (or Vector of Strings in c++)
# It's not clear whether either or both are necessary to write a file.
# It DOES seem to be clear that both will be available after reading a file.
for rinObsType in header.mapObsTypes:
#print "Found obs-type:{}".format(rinObsType)
newObsIds = []
for rinObsId in header.mapObsTypes[rinObsType]:
#print "Found obs-id:{}".format(str(rinObsId))
#print " --type={} code={} band={}".format(rinObsId.type, rinObsId.code, rinObsId.band)
newObsId = gpstk.RinexObsID(str(rinObsId))
newObsIds.append(newObsId)
new_header.mapObsTypes[rinObsType] = tuple(newObsIds)
new_header.valid = new_header.valid | gpstk.Rinex3ObsHeader.validNumObs
for rin_obs_id in header.R2ObsTypes:
#print "Found obs-id:{}".format(rin_obs_id)
new_header.R2ObsTypes.append(rin_obs_id)
new_header.valid = new_header.valid | gpstk.Rinex3ObsHeader.validNumObs
# This creates a new CivilTime object that we can populate
new_header.firstObs = gpstk.CivilTime()
new_header.firstObs.year = header.firstObs.year
new_header.firstObs.month = header.firstObs.month
new_header.firstObs.day = header.firstObs.day
new_header.firstObs.hour = header.firstObs.hour
new_header.firstObs.minute = header.firstObs.minute
new_header.firstObs.second = header.firstObs.second
new_header.valid = new_header.valid | gpstk.Rinex3ObsHeader.validFirstTime
new_header.markerNumber = header.markerNumber
new_header.valid = new_header.valid | gpstk.Rinex3ObsHeader.validMarkerNumber
new_header.interval = header.interval
new_header.valid = new_header.valid | gpstk.Rinex3ObsHeader.validInterval
#####
# Unfortunately, sigStrengthUnit is tied to the wavelengthFactor property,
# We cannot set the latter due to a missing SWIG Python adapter, and
# because the same "validity flag" governs both, we can't output
# sigStrengthUnit without inadvertently outputting a bogus wavelengthFactor.
#####
#new_header.wavelengthFactor = header.wavelengthFactor
#new_header.sigStrengthUnit = header.sigStrengthUnit
#new_header.valid = new_header.valid | gpstk.Rinex3ObsHeader.validSigStrengthUnit
for comment in header.commentList:
new_header.commentList.append(comment)
new_header.valid = new_header.valid | gpstk.Rinex3ObsHeader.validComment
new_header.validEoH = True
# This method is a huge hack to get around a problem in the Rinex3ObsData
# writer. See the method for details.
new_header = tweakInternalHeaderState(new_header)
#print new_header
processed_data = []
# Now we loop through all the epochs and process the data for each one
for d in data:
# This creates a new CommonTime object with the system set to GPS.
timec = gpstk.CommonTime(gpstk.TimeSystem(gpstk.TimeSystem.GPS))
# This creates a new CommonTime object with the system set to GPS.
mjd = int(d.time.getDays())
sod = float(d.time.getSecondOfDay())
timec.set(mjd, sod, gpstk.TimeSystem(gpstk.TimeSystem.GPS))
# Assign values to a new Rinex Obs Data object
nd = gpstk.Rinex3ObsData()
nd.time = timec
nd.auxHeader = d.auxHeader
nd.clockOffset = d.clockOffset
nd.epochFlag = d.epochFlag
nd.numSVs = d.numSVs
for satkey in d.obs.keys():
newSatKey = gpstk.RinexSatID(satkey.toString())
satObss = d.obs[newSatKey]
# satObss is a tuple of RinexDatum
newSatObss = []
for satObs in satObss:
#print "{} {} {} {}".format(satkey.toString(), satObs.data, satObs.lli, satObs.ssi)
newSatObs = gpstk.RinexDatum()
newSatObs.data = satObs.data
newSatObs.lli = satObs.lli
newSatObs.ssi = satObs.ssi
newSatObss.append(newSatObs)
nd.obs[newSatKey] = tuple(newSatObss)
#print "O{}".format(d)
#print "S{}".format(nd)
processed_data.append(nd)
gpstk.writeRinex3Obs(output_file, new_header, processed_data)
print "Wrote output file: {}".format(output_file)
# We can catch any custom gpstk exception like this:
except gpstk.Exception as e:
print e
python ./example5.py rinex2obs_data.txt
"""
import argparse
import gpstk
parser = argparse.ArgumentParser()
parser.add_argument("rinex2obs_filename")
args = parser.parse_args()
try:
print "Reading " + args.rinex2obs_filename + "."
# read in header and get a generator for the data
header, data = gpstk.readRinex3Obs(args.rinex2obs_filename)
print header
for d in data:
civtime = gpstk.CivilTime(d.time)
print civtime
oe = gpstk.ObsEpoch()
oe.time = d.time
for sv in d.obs.keys():
print sv,
epoch = d.obs[sv]
soe = gpstk.SvObsEpoch()
soe.svid = sv
for i in range(len(epoch)):
rinex2_obs_type = header.R2ObsTypes[i]
oid = header.mapObsTypes["G"][i]
def main():
parser = argparse.ArgumentParser()
parser.add_argument('rinex3obs_filename')
parser.add_argument('rinex3nav_filename')
parser.add_argument('-m', '--rinexmet_filename')
args = parser.parse_args()
# Declaration of objects for storing ephemerides and handling RAIM
bcestore = gpstk.GPSEphemerisStore()
raimSolver = gpstk.PRSolution2()
# Object for void-type tropospheric model (in case no meteorological
# RINEX is available)
noTropModel = gpstk.ZeroTropModel()
# Object for GG-type tropospheric model (Goad and Goodman, 1974)
# Default constructor => default values for model
ggTropModel = gpstk.GGTropModel()
# Pointer to one of the two available tropospheric models. It points
# to the void model by default
tropModel = noTropModel
navHeader, navData = gpstk.readRinex3Nav(args.rinex3nav_filename)
for navDataObj in navData:
ephem = navDataObj.toEngEphemeris()
bcestore.addEphemeris(ephem)
# Setting the criteria for looking up ephemeris:
bcestore.SearchNear()
if args.rinexmet_filename is not None:
metHeader, metData = gpstk.readRinexMet(args.rinexmet_filename)
tropModel = ggTropModel
obsHeader, obsData = gpstk.readRinex3Obs(args.rinex3obs_filename)
# The following lines fetch the corresponding indexes for some
# observation types we are interested in. Given that old-style
# observation types are used, GPS is assumed.
try:
indexP1 = obsHeader.getObsIndex('P1')
except:
print 'The observation files has no P1 pseudoranges.'
sys.exit()
try:
indexP2 = obsHeader.getObsIndex('P2')
except:
indexP2 = -1
for obsObj in obsData:
# Find a weather point. Only if a meteorological RINEX file
# was provided, the meteorological data linked list "rml" is
# neither empty or at its end, and the time of meteorological
# records are below observation data epoch.
if args.rinexmet_filename is not None:
for metObj in metData:
if metObj.time >= obsObj.time:
break
else:
metDataDict = metObj.getData()
temp = metDataDict[gpstk.RinexMetHeader.TD]
pressure = metDataDict[gpstk.RinexMetHeader.PR]
humidity = metDataDict[gpstk.RinexMetHeader.HR]
ggTropModel.setWeather(temp, pressure, humidity)
if obsObj.epochFlag == 0 or obsObj.epochFlag == 1:
# Note that we use lists here, but we will need types backed
# by C++ std::vectors later. We'll just keep it easy and use
# gpstk.seqToVector to convert them. If there was a speed
# bottleneck we could use gpstk.cpp.vector_SatID and
# gpstk.cpp.vector_double though.
prnList = []
rangeList = []
# This part gets the PRN numbers and ionosphere-corrected
# pseudoranges for the current epoch. They are correspondly fed
# into "prnList" and "rangeList"; "obs" is a public attribute of
# Rinex3ObsData to get the map of observations
for satID, datumList in obsObj.obs.iteritems():
# The RINEX file may have P1 observations, but the current
# satellite may not have them.
P1 = 0.0
try:
P1 = obsObj.getObs(satID, indexP1).data
except gpstk.exceptions.Exception:
continue # Ignore this satellite if P1 is not found
ionocorr = 0.0
# If there are P2 observations, let's try to apply the
# ionospheric corrections
if indexP2 >= 0:
# The RINEX file may have P2 observations, but the
# current satellite may not have them.
P2 = 0.0
try:
P2 = obsObj.getObs(satID, indexP2).data
except gpstk.exceptions.Exception:
continue # Ignore this satellite if P1 is not found
# list 'vecList' contains RinexDatum, whose public
# attribute "data" indeed holds the actual data point
ionocorr = 1.0 / (1.0 - gpstk.constants.GAMMA_GPS) * (P1 -
P2)
# Now, we include the current PRN number in the first part
# of "it" iterator into the list holding the satellites.
# All satellites in view at this epoch that have P1 or P1+P2
# observations will be included.
prnList.append(satID)
# The same is done for the list of doubles holding the
# corrected ranges
rangeList.append(P1 - ionocorr)
# WARNING: Please note that so far no further correction
# is done on data: Relativistic effects, tropospheric
# correction, instrumental delays, etc
# The default constructor for PRSolution2 objects (like
# "raimSolver") is to set a RMSLimit of 6.5. We change that
# here. With this value of 3e6 the solution will have a lot
# more dispersion.
raimSolver.RMSLimit = 3e6
# In order to compute positions we need the current time, the
# vector of visible satellites, the vector of corresponding
# ranges, the object containing satellite ephemerides, and a
# pointer to the tropospheric model to be applied
time = obsObj.time
# the RAIMComputer method of PRSolution2 accepts a vector<SatID> as its
# 2nd argument, but the list is of RinexSatID, which is a subclass of SatID.
# Since C++ containers are NOT covariant, it is neccessary to change the
# output to a vector or SatID's rather thta a vector of RinexSatID's.
satVector = gpstk.cpp.seqToVector(prnList, outtype='vector_SatID')
rangeVector = gpstk.cpp.seqToVector(rangeList)
raimSolver.RAIMCompute(time, satVector, rangeVector, bcestore,
tropModel)
# Note: Given that the default constructor sets public
# attribute "Algebraic" to FALSE, a linearized least squares
# algorithm will be used to get the solutions.
# Also, the default constructor sets ResidualCriterion to true,
# so the rejection criterion is based on RMS residual of fit,
# instead of RMS distance from an a priori position.
if raimSolver.isValid():
# Vector "Solution" holds the coordinates, expressed in
# meters in an Earth Centered, Earth Fixed (ECEF) reference
# frame. The order is x, y, z (as all ECEF objects)
x, y, z = raimSolver.Solution[0], raimSolver.Solution[
1], raimSolver.Solution[2]
print "%12.5f %12.5f %12.5f" % (x, y, z)
def getdata(nfile, ofile, strsat=None): #one week data
f1, f2 = gpstk.L1_FREQ_GPS, gpstk.L2_FREQ_GPS
alfa = 1.0 / ((f1**2 / f2**2) - 1)
t = [] #observation epoch on code and phase
Iphase, Icode, IPPS = {}, {}, {
} #dicc: key=time observer; values=iono delay and IPP
VTECphase, VTECcode, ELEV = {}, {}, {}
PhaseL1, PhaseL2 = {}, {}
CodeL1, CodeL2 = {}, {}
oheader, odata = gpstk.readRinex3Obs(ofile, strict=True)
nheader, ndata = gpstk.readRinex3Nav(nfile)
bcestore = gpstk.GPSEphemerisStore()
for ndato in ndata:
ephem = ndato.toGPSEphemeris()
bcestore.addEphemeris(ephem)
bcestore.SearchNear()
for observation in odata:
sats = [
satID for satID, datumList in observation.obs.iteritems()
if str(satID).split()[0] == "GPS"
]
obs_types = np.array([i for i in oheader.R2ObsTypes])
if 'C1' and 'P2' and 'L1' and 'L2' in obs_types:
for sat in sats:
if str(sat) == strsat: #Return for a specific satellite
eph = bcestore.findEphemeris(sat, observation.time)
Tgd = eph.Tgd
sat_pos = eph.svXvt(observation.time)
rec_pos = gpstk.Position(
oheader.antennaPosition[0], oheader.antennaPosition[1],
oheader.antennaPosition[2]).asECEF()
elev = oheader.antennaPosition.elvAngle(sat_pos.x)
azim = oheader.antennaPosition.azAngle(sat_pos.x)
time = observation.time
R = 6.378e6 #earth radius
mapp = 1 / np.cos(
np.arcsin(R / (R + 350000)) * np.sin(elev))
IPP = rec_pos.getIonosphericPiercePoint(
elev, azim, 350000).asECEF()
t.append(np.trunc(gpstk.YDSTime(time).sod))
if np.size(np.where(obs_types == 'C1')) > 0 and np.size(
np.where(obs_types == 'P2')) > 0 and np.size(
np.where(obs_types == 'L1')) > 0 and np.size(
np.where(obs_types == 'L2')) > 0:
C1_idx = np.where(obs_types == 'C1')[0][0]
P2_idx = np.where(obs_types == 'P2')[0][0]
R1 = observation.getObs(sat, C1_idx).data
R2 = observation.getObs(sat, P2_idx).data
L1_idx = np.where(obs_types == 'L1')[0][0]
L2_idx = np.where(obs_types == 'L2')[0][0]
L1 = observation.getObs(
sat, L1_idx).data * gpstk.L1_WAVELENGTH_GPS
L2 = observation.getObs(
sat, L2_idx).data * gpstk.L2_WAVELENGTH_GPS
if R2 < 3e7 and R1 < 3e7 and L2 < 3e7 and L1 < 3e7: #Distances should be in order of 1e7 meters, more than that is considered an error
iono_delay_c = alfa * (R2 - R1)
iono_delay_p = alfa * (L1 - L2)
vtec_C = iono_delay_c / mapp
vtec_P = iono_delay_p / mapp
VTECcode[np.trunc(
gpstk.YDSTime(time).sod)] = vtec_C
VTECphase[np.trunc(
gpstk.YDSTime(time).sod)] = vtec_P
Icode[np.trunc(
gpstk.YDSTime(time).sod)] = iono_delay_c
Iphase[np.trunc(
gpstk.YDSTime(time).sod)] = iono_delay_p
ELEV[np.trunc(gpstk.YDSTime(time).sod)] = elev
IPPS[np.trunc(gpstk.YDSTime(time).sod)] = IPP
PhaseL1[np.trunc(gpstk.YDSTime(time).sod)] = L1
PhaseL2[np.trunc(gpstk.YDSTime(time).sod)] = L2
CodeL1[np.trunc(gpstk.YDSTime(time).sod)] = R1
CodeL2[np.trunc(gpstk.YDSTime(time).sod)] = R2
#stec=(iono_delay_p*f1**2)/(-40.3) #STEC delay on phase [mm]
#vtec=stec/mapp #vertical delay!
else:
print "Needs both L1 and L2 frequencies to compute delay"
break
return t, Icode, Iphase, VTECphase, ELEV, IPPS, PhaseL1, PhaseL2, CodeL1, CodeL2, Tgd
import gpstk
import sys
obsfn = gpstk.getPathData() + '/arlm200z.15o'
navfn = gpstk.getPathData() + '/arlm200z.15n'
metfn = gpstk.getPathData() + '/arlm200z.15m'
navHeader, navData = gpstk.readRinex3Nav(navfn)
ephStore = gpstk.gpstk.Rinex3EphemerisStore()
for navDataObj in navData:
ephStore.addEphemeris(navDataObj)
tropModel = gpstk.GGTropModel()
metHeader, metData = gpstk.readRinexMet(metfn)
obsHeader, obsData = gpstk.readRinex3Obs(obsfn)
indexP1 = obsHeader.getObsIndex('C1W')
indexP2 = obsHeader.getObsIndex('C2W')
raimSolver = gpstk.PRSolution2()
for obsObj in obsData:
for metObj in metData:
if metObj.time >= obsObj.time:
break
else:
metDataDict = metObj.getData()
temp = metDataDict[gpstk.RinexMetHeader.TD]
pressure = metDataDict[gpstk.RinexMetHeader.PR]
humidity = metDataDict[gpstk.RinexMetHeader.HR]
tropModel.setWeather(temp, pressure, humidity)
def main():
parser = argparse.ArgumentParser()
parser.add_argument('rinex3obs_filename')
parser.add_argument('rinex3nav_filename')
parser.add_argument('-m', '--rinexmet_filename')
args = parser.parse_args()
# Declaration of objects for storing ephemerides and handling RAIM
bcestore = gpstk.GPSEphemerisStore()
raimSolver = gpstk.PRSolution2()
# Object for void-type tropospheric model (in case no meteorological
# RINEX is available)
noTropModel = gpstk.ZeroTropModel()
# Object for GG-type tropospheric model (Goad and Goodman, 1974)
# Default constructor => default values for model
ggTropModel = gpstk.GGTropModel()
# Pointer to one of the two available tropospheric models. It points
# to the void model by default
tropModel = noTropModel
navHeader, navData = gpstk.readRinex3Nav(args.rinex3nav_filename)
for navDataObj in navData:
ephem = navDataObj.toEngEphemeris()
bcestore.addEphemeris(ephem)
# Setting the criteria for looking up ephemeris:
bcestore.SearchNear()
if args.rinexmet_filename is not None:
metHeader, metData = gpstk.readRinexMet(args.rinexmet_filename)
tropModel = ggTropModel
obsHeader, obsData = gpstk.readRinex3Obs(args.rinex3obs_filename)
# The following lines fetch the corresponding indexes for some
# observation types we are interested in. Given that old-style
# observation types are used, GPS is assumed.
try:
indexP1 = obsHeader.getObsIndex('C1P')
except:
print 'The observation files has no L1 C/A pseudoranges.'
sys.exit()
try:
indexP2 = obsHeader.getObsIndex('C2W')
except:
print 'The observation files has no L2 codeless pseudoranges.'
indexP2 = -1
for obsObj in obsData:
# Find a weather point. Only if a meteorological RINEX file
# was provided, the meteorological data linked list "rml" is
# neither empty or at its end, and the time of meteorological
# records are below observation data epoch.
if args.rinexmet_filename is not None:
for metObj in metData:
if metObj.time >= obsObj.time:
break
else:
metDataDict = metObj.getData()
temp = metDataDict[gpstk.RinexMetHeader.TD]
pressure = metDataDict[gpstk.RinexMetHeader.PR]
humidity = metDataDict[gpstk.RinexMetHeader.HR]
ggTropModel.setWeather(temp, pressure, humidity)
if obsObj.epochFlag == 0 or obsObj.epochFlag == 1:
# Note that we use lists here, but we will need types backed
# by C++ std::vectors later. We'll just keep it easy and use
# gpstk.seqToVector to convert them. If there was a speed
# bottleneck we could use gpstk.cpp.vector_SatID and
# gpstk.cpp.vector_double though.
prnList = []
rangeList = []
# This part gets the PRN numbers and ionosphere-corrected
# pseudoranges for the current epoch. They are correspondly fed
# into "prnList" and "rangeList"; "obs" is a public attribute of
# Rinex3ObsData to get the map of observations
for satID, datumList in obsObj.obs.iteritems():
# The RINEX file may have P1 observations, but the current
# satellite may not have them.
P1 = 0.0
try:
P1 = obsObj.getObs(satID, indexP1).data
except gpstk.exceptions.Exception:
continue # Ignore this satellite if P1 is not found
ionocorr = 0.0
# If there are P2 observations, let's try to apply the
# ionospheric corrections
if indexP2 >= 0:
# The RINEX file may have P2 observations, but the
# current satellite may not have them.
P2 = 0.0
try:
P2 = obsObj.getObs(satID, indexP2).data
except gpstk.exceptions.Exception:
continue # Ignore this satellite if P1 is not found
# list 'vecList' contains RinexDatum, whose public
# attribute "data" indeed holds the actual data point
ionocorr = 1.0 / (1.0 - gpstk.GAMMA_GPS) * ( P1 - P2 )
# Now, we include the current PRN number in the first part
# of "it" iterator into the list holding the satellites.
# All satellites in view at this epoch that have P1 or P1+P2
# observations will be included.
prnList.append(satID)
# The same is done for the list of doubles holding the
# corrected ranges
rangeList.append(P1 - ionocorr)
# WARNING: Please note that so far no further correction
# is done on data: Relativistic effects, tropospheric
# correction, instrumental delays, etc
# The default constructor for PRSolution2 objects (like
# "raimSolver") is to set a RMSLimit of 6.5. We change that
# here. With this value of 3e6 the solution will have a lot
# more dispersion.
raimSolver.RMSLimit = 3e6
# In order to compute positions we need the current time, the
# vector of visible satellites, the vector of corresponding
# ranges, the object containing satellite ephemerides, and a
# pointer to the tropospheric model to be applied
time = obsObj.time
# the RAIMComputer method of PRSolution2 accepts a vector<SatID> as its
# 2nd argument, but the list is of RinexSatID, which is a subclass of SatID.
# Since C++ containers are NOT covariant, it is neccessary to change the
# output to a vector or SatID's rather thta a vector of RinexSatID's.
satVector = gpstk.cpp.seqToVector(prnList, outtype='vector_SatID')
rangeVector = gpstk.cpp.seqToVector(rangeList)
raimSolver.RAIMCompute(time, satVector, rangeVector, bcestore, tropModel)
# Note: Given that the default constructor sets public
# attribute "Algebraic" to FALSE, a linearized least squares
# algorithm will be used to get the solutions.
# Also, the default constructor sets ResidualCriterion to true,
# so the rejection criterion is based on RMS residual of fit,
# instead of RMS distance from an a priori position.
if raimSolver.isValid():
# Vector "Solution" holds the coordinates, expressed in
# meters in an Earth Centered, Earth Fixed (ECEF) reference
# frame. The order is x, y, z (as all ECEF objects)
x, y, z = raimSolver.Solution[0], raimSolver.Solution[1], raimSolver.Solution[2]
print "%12.5f %12.5f %12.5f" % (x, y, z)
