def getVisibilityHeader(f):
offset = f.tell()
h = parseDiFX.parse_output_header(f)
rdlen = f.tell() - offset
f.seek(offset)
bin = f.read(rdlen)
return (h, bin)
def getVisibilityHeader(f):
"""Read next DiFX file visibility header and return it in binary was well as a parsed struct"""
bin = None
offset = f.tell()
h = parseDiFX.parse_output_header(f)
if h:
rdlen = f.tell() - offset
f.seek(offset)
bin = f.read(rdlen)
return (h, bin)
def checkDiFXViz(job, opts):
'''Inspect the DiFX output of a job (<job>.difx/DIFX_*) and look at the polarizations of the visibility data'''
# Antennas that are linear polarized
linear_antennas = ['AA']
# Read the .input file of the job
inputfile = job + '.input'
commoncfg = parseDiFX.get_common_settings(inputfile)
(numfreqs, freqs) = parseDiFX.get_freqtable_info(inputfile)
(numtelescopes, telescopes) = parseDiFX.get_telescopetable_info(inputfile)
if numfreqs == 0:
print("Couldn't parse input file " + inputfile + " correctly")
return False
antennas = [t.name for t in telescopes]
has_linpol_ant = any(a in linear_antennas for a in antennas)
Nvis_stop = numfreqs * 4 * numtelescopes * (numtelescopes - 1) / 2
# Read the .difx/DIFX_* file referred to from .input
glob_pattern = commoncfg['difxfile'] + '/DIFX_*.s*.b*'
difxfileslist = glob.glob(glob_pattern)
if len(difxfileslist) <= 0:
print('Error: no visibility data file found in %s!' % (glob_pattern))
return
difxfilename = difxfileslist[
0] # first file only; TODO what if multiple files?
difxfile = open(difxfilename, 'r')
# Check visibility records
Nvis = 0
Nvis_linant = 0
pols_crossed = False
pols_found = []
while True:
hdr = parseDiFX.parse_output_header(difxfile)
if len(hdr) == 0:
break
[
baseline, mjd, seconds, cfgidx, srcidx, freqindex, polpair,
pulsarbin, weight, u, v, w, rawhdr
] = hdr
ant2name = telescopes[
(baseline % 256) -
1] # order as in difx2mark4: ref=ant1="256*nr", rem=ant2="nr%256"
ant1name = telescopes[((baseline - (baseline % 256)) / 256) - 1]
nchan = freqs[freqindex].numchan / freqs[freqindex].specavg
difxfile.seek(8 * nchan, 1)
Nvis = Nvis + 1
if polpair[0] != polpair[1]:
pols_crossed = True
if polpair[0] not in pols_found:
pols_found.append(polpair[0])
if polpair[1] not in pols_found:
pols_found.append(polpair[1])
if has_linpol_ant:
if ((ant1name in linear_antennas)
or (ant2name in linear_antennas)):
Nvis_linant = Nvis_linant + 1
if Nvis_linant > Nvis_stop:
break
else:
if (Nvis > Nvis_stop):
break
# Summary
pols_circular = ('L' in pols_found) or ('R' in pols_found)
pols_linear = ('X' in pols_found) or ('Y' in pols_found)
pols_full = ('L' in pols_found) and ('R' in pols_found)
pols_full = pols_full or (('X' in pols_found) and ('Y' in pols_found))
if pols_circular and pols_linear:
polinfo = opts.colors.RED + 'mixed' + opts.colors.ENDC
elif pols_circular:
polinfo = 'circular'
else:
polinfo = 'linear'
if pols_full:
if pols_crossed:
polinfo += ' full-Stokes'
else:
polinfo += ' half-Stokes'
if not opts.doShort:
polinfo += ' in ' + difxfilename
return polinfo
if numfreqs == 0:
parser.error("Couldn't parse input file " + inputfile + " correctly!")
if not os.path.exists(args[0]):
parser.error("Input difx file %s doesn't exist!" % (args[0]))
if os.path.exists(args[1]):
parser.error("Output difx file %s already exists!" % (args[1]))
starttime = float(timerange[0])
stoptime = float(timerange[1])
difxinput = open(args[0])
difxoutput = open(args[1], 'w')
vis = []
for j in range(maxchannels):
vis.append(0.0)
nextheader = parseDiFX.parse_output_header(difxinput)
if len(nextheader) == 0:
print("Problem with input file " + args[0] + " - aborting")
sys.exit()
startmjd = nextheader[1]
while not len(nextheader) == 0:
freqindex = nextheader[5]
nchan = freqs[freqindex].numchan / freqs[freqindex].specavg
if nchan > maxchannels:
print ("How embarrassing - you have tried to read files with more than " + \
str(maxchannels) + " channels. Please rerun with --maxchannels=<bigger number>!")
sys.exit()
mjd = nextheader[1]
seconds = nextheader[2]
buffer = difxinput.read(8 * nchan)
amp=[]
phase=[]
for i in range(numfreqs):
amp.append([])
phase.append([])
for j in range(maxchannels):
amp[i].append([])
phase[i].append([])
chans = []
for i in range(maxchannels):
chans.append(i)
difxinputA = open(args[0])
difxinputB = open(args[1])
nextheaderA = parseDiFX.parse_output_header(difxinputA)
nextheaderB = parseDiFX.parse_output_header(difxinputB)
savednchan = -1
vislen = 0
lastseconds = -1
while not len(nextheaderA) == 0:
baseline = nextheaderA[0]
mjd = nextheaderA[1]
seconds = nextheaderA[2]
freqindex = nextheaderA[5]
polpair = nextheaderA[6]
nchan = freqs[freqindex].numchan/freqs[freqindex].specavg
if nchan > maxchannels:
print ("How embarrassing - you have tried to read files with more than " + \
str(maxchannels) + " channels. Please rerun with --maxchannels=<bigger number>!")
sys.exit()
freqindex = []
baseline = []
nchan = []
mjd = []
seconds = []
for filename in args:
difxinputs.append(open(filename, 'rb'))
freqindex.append(0)
nchan.append(0)
baseline.append(0)
mjd.append(0)
seconds.append(0)
nextheader.append([])
for i in range(numfiles):
nextheader[i] = parseDiFX.parse_output_header(difxinputs[i])
recordcount = 0
headerdisagreecount = 0
longtermabsdiff = 0.0
longtermmeandiff = complex(0.0, 0.0)
disagreeskip = -1
while not len(nextheader[0]) == 0 and not len(nextheader[1]) == 0:
if maxrecords > 0:
readrecords = recordcount - skiprecords
if readrecords >= maxrecords:
print("Have examined " + str(readrecords) + " - finishing up!")
break
for i in range(numfiles):
baseline[i] = nextheader[i][0]
freqindex[i] = nextheader[i][5]
