def AddMagneticCoordinates(sourceFilename, resultFilename):
startSecs = time.time()
prev_time = current_time = None
timestep = 0
linenum = 0
CSVfileOUT = open(resultFilename, 'w')
CSVwriter = csv.writer(CSVfileOUT, delimiter=',')
CSVwriter.writerow([
"Epoch(UTCG)", "Lat_GEOD(deg)", "Lon_GEOD(deg)", "Height_WGS84 (km)",
"Daedalus.Magnetic Latitude", "Daedalus.Magnetic Longitude",
"Daedalus.MLT"
])
with open(sourceFilename) as CSVfileIN:
CSVreader = csv.reader(CSVfileIN)
# locate the column numnbers of interest inside the csv file
CSVheader = next(CSVreader)
Time_idx = CSVheader.index(
"Epoch(UTCG)") #CSVheader.index( "Daedalus.EpochText" )
Lat_idx = CSVheader.index(
"Lat_GEOD(deg)") #CSVheader.index( "Daedalus.Latitude" )
Lon_idx = CSVheader.index(
"Lon_GEOD(deg)") #CSVheader.index( "Daedalus.Longitude" )
Alt_idx = CSVheader.index(
"Height_WGS84 (km)") #CSVheader.index( "Daedalus.Longitude" )
# read the orbit file
for row in CSVreader: # for each satellite position
if len(list(row)) == 0: break # <<<<
linenum += 1
resultItems = list()
# add the standard fields to the result file
resultItems.append(row[Time_idx])
resultItems.append(
row[Lat_idx]) # Latitude is geodetic inside the orbit file
resultItems.append(row[Lon_idx])
resultItems.append(row[Alt_idx])
# Calculate the extra fields
prev_time = current_time
current_time = parseDaedalusDate(
row[Time_idx]) # read time for the current orbit position
if current_time == None:
print("ERROR - Wrong time format at line", linenum, ":",
row[Time_idx])
continue
if prev_time is not None:
if timestep == 0:
timestep = calendar.timegm(
current_time.utctimetuple()) - calendar.timegm(
prev_time.utctimetuple())
else:
if calendar.timegm(
current_time.utctimetuple()) - calendar.timegm(
prev_time.utctimetuple()) != timestep:
print(
"Time leap at line", linenum, ":", row, "(",
calendar.timegm(current_time.utctimetuple()) -
calendar.timegm(prev_time.utctimetuple()), "sec)",
"\n", prev_time, "\n", current_time)
# take care of time so that it is compatible with igrf
#if current_time.year > 2024:
# time_for_igrf = current_time - relativedelta(years=13)
#else:
# time_for_igrf = current_time
time_for_igrf = current_time
MagneticLatitude, MagneticLongitude, MagneticLocalTime = Conversions.getMagneticProperties(
time_for_igrf, float(row[Lat_idx]), float(row[Lon_idx]),
float(row[Alt_idx]))
# add the extra fields to the result file
resultItems.append(MagneticLatitude)
resultItems.append(MagneticLongitude)
resultItems.append(MagneticLocalTime)
# write it
CSVwriter.writerow(resultItems)
# clean up
CSVfileOUT.close()
finishSecs = time.time()
print("Processed", linenum, "lines in", finishSecs - startSecs, "sec")
