def test_rec_frame(self):
rec_frame = ReceptorFrame("linear")
assert rec_frame.nrec == 2
rec_frame = ReceptorFrame("circular")
assert rec_frame.nrec == 2
rec_frame = ReceptorFrame("stokesI")
assert rec_frame.nrec == 1
with self.assertRaises(ValueError):
rec_frame = ReceptorFrame("circuloid")
def convert_configuration_from_hdf(f):
""" Extyract configuration from HDF
:param f:
:return:
"""
cf = f['configuration']
assert cf.attrs[
'ARL_data_model'] == "Configuration", "%s is a Configuration" % cf.attrs[
'ARL_data_model']
name = cf.attrs['name']
location = convert_earthlocation_from_string(cf.attrs['location'])
receptor_frame = ReceptorFrame(cf.attrs['receptor_frame'])
frame = cf.attrs['frame']
xyz = cf['configuration/xyz']
diameter = cf['configuration/diameter']
names = [str(n) for n in cf['configuration/names']]
mount = [str(m) for m in cf['configuration/mount']]
return Configuration(name=name,
location=location,
receptor_frame=receptor_frame,
xyz=xyz,
frame=frame,
diameter=diameter,
names=names,
mount=mount)
def convert_hdf_to_gaintable(f):
""" Convert HDF root to a GainTable
:param f:
:return:
"""
assert f.attrs['ARL_data_model'] == "GainTable", "Not a GainTable"
receptor_frame = ReceptorFrame(f.attrs['receptor_frame'])
frequency = numpy.array(f.attrs['frequency'])
data = numpy.array(f['data'])
gt = GainTable(data=data, receptor_frame=receptor_frame, frequency=frequency)
return gt
def __init__(self,
data=None,
pointing: numpy.array = None,
nominal: numpy.array = None,
time: numpy.array = None,
interval=None,
weight: numpy.array = None,
residual: numpy.array = None,
frequency: numpy.array = None,
receptor_frame: ReceptorFrame = ReceptorFrame("linear"),
pointing_frame: str = "local",
pointingcentre=None,
configuration=None):
""" Create a pointing from arrays
:param interval:
:param data:
:param pointing: [:, nchan, nrec, 2]
:param nominal: [:, nchan, nrec, 2]
:param time: Centroid of solution
:param interval: Interval of validity
:param weight:
:param residual:
:param frequency:
:param receptor_frame:
:return: PointingTable
"""
if data is None and pointing is not None:
nrec = receptor_frame.nrec
nrows = pointing.shape[0]
nants = pointing.shape[1]
nchan = pointing.shape[2]
assert len(frequency) == nchan, "Discrepancy in frequency channels"
desc = [('pointing', 'f16', (nants, nchan, nrec, 2)),
('nominal', 'f16', (nants, nchan, nrec, 2)),
('weight', 'f8', (nants, nchan, nrec, 2)),
('residual', 'f8', (nchan, nrec, 2)), ('time', 'f8'),
('interval', 'f8')]
data = numpy.zeros(shape=[nrows], dtype=desc)
data['pointing'] = pointing
data['weight'] = weight
data['time'] = time
data['interval'] = interval
data['residual'] = residual
data['nominal'] = nominal
self.data = data
self.frequency = frequency
self.receptor_frame = receptor_frame
self.pointing_frame = pointing_frame
self.pointingcentre = pointingcentre
self.configuration = configuration
def convert_hdf_to_gaintable(f):
""" Convert HDF root to a GainTable
:param f:
:return:
"""
assert f.attrs['ARL_data_model'] == "GainTable", "Not a GainTable"
receptor_frame = ReceptorFrame(f.attrs['receptor_frame'])
frequency = numpy.array(f.attrs['frequency'])
data = numpy.array(f['data'])
s = f.attrs['phasecentre_coords'].split()
ss = [float(s[0]), float(s[1])] * u.deg
phasecentre = SkyCoord(ra=ss[0], dec=ss[1], frame=f.attrs['phasecentre_frame'])
gt = GainTable(data=data, receptor_frame=receptor_frame, frequency=frequency, phasecentre=phasecentre)
return gt
def __init__(self,
data=None,
gain: numpy.array = None,
time: numpy.array = None,
interval=None,
weight: numpy.array = None,
residual: numpy.array = None,
frequency: numpy.array = None,
receptor_frame: ReceptorFrame = ReceptorFrame("linear"),
phasecentre=None):
""" Create a gaintable from arrays
The definition of gain is:
Vobs = g_i g_j^* Vmodel
:param interval:
:param data:
:param gain: [:, nchan, nrec, nrec]
:param time: Centroid of solution
:param interval: Interval of validity
:param weight:
:param residual:
:param frequency:
:param receptor_frame:
:return: Gaintable
"""
if data is None and gain is not None:
nrec = receptor_frame.nrec
nrows = gain.shape[0]
nants = gain.shape[1]
nchan = gain.shape[2]
assert len(frequency) == nchan, "Discrepancy in frequency channels"
desc = [('gain', 'c16', (nants, nchan, nrec, nrec)),
('weight', 'f8', (nants, nchan, nrec, nrec)),
('residual', 'f8', (nchan, nrec, nrec)), ('time', 'f8'),
('interval', 'f8')]
data = numpy.zeros(shape=[nrows], dtype=desc)
data['gain'] = gain
data['weight'] = weight
data['time'] = time
data['interval'] = interval
data['residual'] = residual
self.data = data
self.frequency = frequency
self.receptor_frame = receptor_frame
self.phasecentre = phasecentre
def convert_hdf_to_pointingtable(f):
""" Convert HDF root to a PointingTable
:param f:
:return:
"""
assert f.attrs['ARL_data_model'] == "PointingTable", "Not a PointingTable"
receptor_frame = ReceptorFrame(f.attrs['receptor_frame'])
frequency = numpy.array(f.attrs['frequency'])
data = numpy.array(f['data'])
s = f.attrs['pointingcentre_coords'].split()
ss = [float(s[0]), float(s[1])] * u.deg
pointingcentre = SkyCoord(ra=ss[0], dec=ss[1], frame=f.attrs['pointingcentre_frame'])
pointing_frame = f.attrs['pointing_frame']
pt = PointingTable(data=data, frequency=frequency, receptor_frame=receptor_frame, pointing_frame=pointing_frame,
pointingcentre=pointingcentre)
return pt
def __init__(self,
name='',
data=None,
location=None,
names="%s",
xyz=None,
mount="alt-az",
frame="",
receptor_frame=ReceptorFrame("linear"),
diameter=None):
"""Configuration object describing data for processing
:param name:
:param data:
:param location:
:param names:
:param xyz:
:param mount:
:param frame:
:param receptor_frame:
:param diameter:
"""
if data is None and xyz is not None:
desc = [('names', 'U12'), ('xyz', 'f8', (3, )), ('diameter', 'f8'),
('mount', 'U5')]
nants = xyz.shape[0]
if isinstance(names, str):
names = [names % ant for ant in range(nants)]
if isinstance(mount, str):
mount = numpy.repeat(mount, nants)
data = numpy.zeros(shape=[nants], dtype=desc)
data['names'] = names
data['xyz'] = xyz
data['mount'] = mount
data['diameter'] = diameter
self.name = name
self.data = data
self.location = location
self.frame = frame
self.receptor_frame = receptor_frame
def create_visibility_from_ms(msname, channum=0, ack=False):
""" Minimal MS to Visibility converter
The MS format is much more general than the ARL Visibility so we cut many corners. This requires casacore to be
installed. If not an exception ModuleNotFoundError is raised.
Creates a list of Visibilities, one per phasecentre
"""
try:
from casacore.tables import table # pylint: disable=import-error
except ModuleNotFoundError:
raise ModuleNotFoundError("casacore is not installed")
tab = table(msname, ack=ack)
log.debug("create_visibility_from_ms: %s" % str(tab.info()))
fields = numpy.unique(tab.getcol('FIELD_ID'))
log.debug("create_visibility_from_ms: Found unique field ids %s" %
str(fields))
vis_list = list()
for field in fields:
# First get the main table information
ms = tab.query("FIELD_ID==%d" % field)
log.debug("create_visibility_from_ms: Found %d rows for field %d" %
(ms.nrows(), field))
time = ms.getcol('TIME')
channels = len(numpy.transpose(ms.getcol('DATA'))[0])
log.debug("create_visibility_from_ms: Found %d channels" % (channels))
try:
vis = ms.getcol('DATA')[:, channum, :]
except IndexError:
raise IndexError("channel number exceeds max. within ms")
weight = ms.getcol('WEIGHT')
uvw = -1 * ms.getcol('UVW')
antenna1 = ms.getcol('ANTENNA1')
antenna2 = ms.getcol('ANTENNA2')
integration_time = ms.getcol('INTERVAL')
ddid = ms.getcol('DATA_DESC_ID')
# Now get info from the subtables
spwtab = table('%s/SPECTRAL_WINDOW' % msname, ack=False)
cfrequency = spwtab.getcol('CHAN_FREQ')
frequency = numpy.array([cfrequency[dd] for dd in ddid])[:, channum]
cchannel_bandwidth = spwtab.getcol('CHAN_WIDTH')
channel_bandwidth = numpy.array(
[cchannel_bandwidth[dd] for dd in ddid])[:, 0]
uvw *= frequency[:, numpy.newaxis] / constants.c.to('m s^-1').value
# Get polarisation info
poltab = table('%s/POLARIZATION' % msname, ack=False)
corr_type = poltab.getcol('CORR_TYPE')
# These correspond to the CASA Stokes enumerations
if numpy.array_equal(corr_type[0], [1, 2, 3, 4]):
polarisation_frame = PolarisationFrame('stokesIQUV')
elif numpy.array_equal(corr_type[0], [5, 6, 7, 8]):
polarisation_frame = PolarisationFrame('circular')
elif numpy.array_equal(corr_type[0], [9, 10, 11, 12]):
polarisation_frame = PolarisationFrame('linear')
else:
raise KeyError("Polarisation not understood: %s" % str(corr_type))
print("create_visibility_from_ms: polarisation %s" %
polarisation_frame.type)
# Get configuration
anttab = table('%s/ANTENNA' % msname, ack=False)
mount = anttab.getcol('MOUNT')
names = anttab.getcol('NAME')
diameter = anttab.getcol('DISH_DIAMETER')
xyz = anttab.getcol('POSITION')
configuration = Configuration(name='',
data=None,
location=None,
names=names,
xyz=xyz,
mount=mount,
frame=None,
receptor_frame=ReceptorFrame("linear"),
diameter=diameter)
# Get phasecentres
fieldtab = table('%s/FIELD' % msname, ack=False)
pc = fieldtab.getcol('PHASE_DIR')[field, 0, :]
phasecentre = SkyCoord(ra=[pc[0]] * u.rad,
dec=pc[1] * u.rad,
frame='icrs',
equinox='J2000')
vis_list.append(
Visibility(uvw=uvw,
time=time,
antenna1=antenna1,
antenna2=antenna2,
frequency=frequency,
vis=vis,
weight=weight,
imaging_weight=weight,
integration_time=integration_time,
channel_bandwidth=channel_bandwidth,
configuration=configuration,
phasecentre=phasecentre,
polarisation_frame=polarisation_frame))
return vis_list
def create_blockvisibility_from_ms(msname, channum=None, ack=False):
""" Minimal MS to BlockVisibility converter
The MS format is much more general than the ARL BlockVisibility so we cut many corners. This requires casacore to be
installed. If not an exception ModuleNotFoundError is raised.
Creates a list of BlockVisibility's, split by field and spectral window
:param msname: File name of MS
:param channum: range of channels e.g. range(17,32), default is None meaning all
:return:
"""
try:
from casacore.tables import table # pylint: disable=import-error
except ModuleNotFoundError:
raise ModuleNotFoundError("casacore is not installed")
tab = table(msname, ack=ack)
log.debug("create_blockvisibility_from_ms: %s" % str(tab.info()))
fields = numpy.unique(tab.getcol('FIELD_ID'))
dds = numpy.unique(tab.getcol('DATA_DESC_ID'))
log.debug(
"create_blockvisibility_from_ms: Found unique fields %s, unique data descriptions %s"
% (str(fields), str(dds)))
vis_list = list()
for dd in dds:
dtab = table(msname, ack=ack).query('DATA_DESC_ID==%d' % dd, style='')
for field in fields:
ms = dtab.query('FIELD_ID==%d' % field, style='')
assert ms.nrows(
) > 0, "Empty selection for FIELD_ID=%d and DATA_DESC_ID=%d" % (
field, dd)
log.debug("create_blockvisibility_from_ms: Found %d rows" %
(ms.nrows()))
time = ms.getcol('TIME')
channels = ms.getcol('DATA').shape[-2]
log.debug("create_visibility_from_ms: Found %d channels" %
(channels))
if channum is None:
channum = range(channels)
try:
ms_vis = ms.getcol('DATA')[:, channum, :]
ms_weight = ms.getcol('WEIGHT')[:, :]
except IndexError:
raise IndexError("channel number exceeds max. within ms")
uvw = -1 * ms.getcol('UVW')
antenna1 = ms.getcol('ANTENNA1')
antenna2 = ms.getcol('ANTENNA2')
integration_time = ms.getcol('INTERVAL')
# Now get info from the subtables
spwtab = table('%s/SPECTRAL_WINDOW' % msname, ack=False)
cfrequency = spwtab.getcol('CHAN_FREQ')[dd][channum]
cchannel_bandwidth = spwtab.getcol('CHAN_WIDTH')[dd][channum]
nchan = cfrequency.shape[0]
# Get polarisation info
poltab = table('%s/POLARIZATION' % msname, ack=False)
corr_type = poltab.getcol('CORR_TYPE')
# These correspond to the CASA Stokes enumerations
if numpy.array_equal(corr_type[0], [1, 2, 3, 4]):
polarisation_frame = PolarisationFrame('stokesIQUV')
elif numpy.array_equal(corr_type[0], [5, 6, 7, 8]):
polarisation_frame = PolarisationFrame('circular')
elif numpy.array_equal(corr_type[0], [9, 10, 11, 12]):
polarisation_frame = PolarisationFrame('linear')
else:
raise KeyError("Polarisation not understood: %s" %
str(corr_type))
npol = 4
# Get configuration
anttab = table('%s/ANTENNA' % msname, ack=False)
nants = anttab.nrows()
mount = anttab.getcol('MOUNT')
names = anttab.getcol('NAME')
diameter = anttab.getcol('DISH_DIAMETER')
xyz = anttab.getcol('POSITION')
configuration = Configuration(
name='',
data=None,
location=None,
names=names,
xyz=xyz,
mount=mount,
frame=None,
receptor_frame=ReceptorFrame("linear"),
diameter=diameter)
# Get phasecentres
fieldtab = table('%s/FIELD' % msname, ack=False)
pc = fieldtab.getcol('PHASE_DIR')[field, 0, :]
phasecentre = SkyCoord(ra=[pc[0]] * u.rad,
dec=pc[1] * u.rad,
frame='icrs',
equinox='J2000')
bv_times = numpy.unique(time)
ntimes = len(bv_times)
bv_vis = numpy.zeros([ntimes, nants, nants, nchan,
npol]).astype('complex')
bv_weight = numpy.zeros([ntimes, nants, nants, nchan, npol])
bv_uvw = numpy.zeros([ntimes, nants, nants, 3])
time_last = time[0]
time_index = 0
for row, _ in enumerate(ms_vis):
# MS has shape [row, npol, nchan]
# BV has shape [ntimes, nants, nants, nchan, npol]
if time[row] != time_last:
assert time[
row] > time_last, "MS is not time-sorted - cannot convert"
time_index += 1
time_last = time[row]
bv_vis[time_index, antenna2[row], antenna1[row],
...] = ms_vis[row, ...]
bv_weight[time_index, antenna2[row], antenna1[row], :,
...] = ms_weight[row, numpy.newaxis, ...]
bv_uvw[time_index, antenna2[row],
antenna1[row], :] = uvw[row, :]
vis_list.append(
BlockVisibility(uvw=bv_uvw,
time=bv_times,
frequency=cfrequency,
channel_bandwidth=cchannel_bandwidth,
vis=bv_vis,
weight=bv_weight,
configuration=configuration,
phasecentre=phasecentre,
polarisation_frame=polarisation_frame))
tab.close()
return vis_list
def test_congruent(self):
for frame in ["linear", "circular", "stokesI"]:
assert congruent_polarisation(ReceptorFrame(frame),
PolarisationFrame(frame))
assert not congruent_polarisation(ReceptorFrame(frame),
PolarisationFrame("stokesIQUV"))
def test_correlate(self):
for frame in ["linear", "circular", "stokesI"]:
rec_frame = ReceptorFrame(frame)
assert correlate_polarisation(rec_frame) == PolarisationFrame(
frame)
def create_visibility_from_ms_maps(msname, poldef):
""" Minimal MS to Visibility converter
The MS format is much more general than the ARL Visibility so we cut many corners. This requires casacore to be
installed. If not an exception ModuleNotFoundError is raised.
Creates a list of Visibilities, one per phasecentre
"""
try:
from casacore.tables import table # pylint: disable=import-error
except ModuleNotFoundError:
raise ModuleNotFoundError("casacore is not installed")
tab = table(msname)
print(tab.info())
fields = numpy.unique(tab.getcol('FIELD_ID'))
print("Found unique field ids %s" % fields)
# for field in fields:
# First get the main table information
ms = tab.query("FIELD_ID==%d" % fields[0])
print("Found %d rows for field %d" % (ms.nrows(), fields[0]))
time = ms.getcol('TIME')
weight = ms.getcol('WEIGHT')
uvw = -1 * ms.getcol('UVW')
antenna1 = ms.getcol('ANTENNA1')
antenna2 = ms.getcol('ANTENNA2')
integration_time = ms.getcol('INTERVAL')
ddid = ms.getcol('DATA_DESC_ID')
# Get polarisation info
# poltab = table('%s/POLARIZATION' % msname, ack=False)
# corr_type = poltab.getcol('CORR_TYPE')
# TODO: Do interpretation correctly
# polarisation_frame = PolarisationFrame('stokesIQUV')
# Set the polarisation frame:
if poldef == 'lin':
polarisation_frame = PolarisationFrame('linear')
if poldef == 'circ':
polarisation_frame = PolarisationFrame('circular')
# Get configuration
anttab = table('%s/ANTENNA' % msname, ack=False)
mount = anttab.getcol('MOUNT')
names = anttab.getcol('NAME')
diameter = anttab.getcol('DISH_DIAMETER')
xyz = anttab.getcol('POSITION')
configuration = Configuration(name='', data=None, location=None, names=names, xyz=xyz, mount=mount, frame=None, receptor_frame=ReceptorFrame("linear"), diameter=diameter)
# Get phasecentres
fieldtab = table('%s/FIELD' % msname, ack=False)
pc = fieldtab.getcol('PHASE_DIR')[fields[0], 0, :]
print(pc[0], pc[1])
phasecentre = SkyCoord(ra=[pc[0]] * u.rad, dec=pc[1] * u.rad, frame='icrs', equinox='J2000')
channels = len(numpy.transpose(ms.getcol('DATA'))[0])
print("Found %d channels" % (channels))
spwtab = table('%s/SPECTRAL_WINDOW' % msname, ack=False)
cfrequency = spwtab.getcol('CHAN_FREQ')
cchannel_bandwidth = spwtab.getcol('CHAN_WIDTH')
channel_bandwidth = numpy.array([cchannel_bandwidth[dd] for dd in ddid])[:, 0]
# Now get info from the subtables
maps_data = list()
for channum in range(channels):
try:
vis = ms.getcol('DATA')[:, channum, :]
except IndexError:
raise IndexError("channel number exceeds max. within ms")
frequency = numpy.array([cfrequency[dd] for dd in ddid])[:, channum]
uvw *= frequency[:, numpy.newaxis] / constants.c.to('m/s').value
vis_list = Visibility(uvw=uvw, time=time, antenna1=antenna1, antenna2=antenna2,
frequency=frequency, vis=vis,
weight=weight, imaging_weight=weight,
integration_time=integration_time,
channel_bandwidth=channel_bandwidth,
configuration=configuration,
phasecentre=phasecentre,
polarisation_frame=polarisation_frame)
maps_data.append(vis_list)
return maps_data
def create_blockvisibility_from_ms(msname, channum=None, start_chan=None, end_chan=None, ack=False,
datacolumn='DATA', selected_sources=None, selected_dds=None):
""" Minimal MS to BlockVisibility converter
The MS format is much more general than the ARL BlockVisibility so we cut many corners. This requires casacore to be
installed. If not an exception ModuleNotFoundError is raised.
Creates a list of BlockVisibility's, split by field and spectral window
Reading of a subset of channels is possible using either start_chan and end_chan or channnum. Using start_chan
and end_chan is preferred since it only reads the channels required. Channum is more flexible and can be used to
read a random list of channels.
:param msname: File name of MS
:param channum: range of channels e.g. range(17,32), default is None meaning all
:param start_chan: Starting channel to read
:param end_chan: End channel to read
:return:
"""
try:
from casacore.tables import table # pylint: disable=import-error
except ModuleNotFoundError:
raise ModuleNotFoundError("casacore is not installed")
try:
from processing_components.visibility import msv2
except ModuleNotFoundError:
raise ModuleNotFoundError("cannot import msv2")
tab = table(msname, ack=ack)
log.debug("create_blockvisibility_from_ms: %s" % str(tab.info()))
if selected_sources is None:
fields = numpy.unique(tab.getcol('FIELD_ID'))
else:
fieldtab = table('%s/FIELD' % msname, ack=False)
sources = fieldtab.getcol('NAME')
fields = list()
for field, source in enumerate(sources):
if source in selected_sources: fields.append(field)
assert len(fields) > 0, "No sources selected"
if selected_dds is None:
dds = numpy.unique(tab.getcol('DATA_DESC_ID'))
else:
dds = selected_dds
log.debug("create_blockvisibility_from_ms: Reading unique fields %s, unique data descriptions %s" % (
str(fields), str(dds)))
vis_list = list()
for field in fields:
ftab = table(msname, ack=ack).query('FIELD_ID==%d' % field, style='')
for dd in dds:
meta = {'MSV2':{'FIELD_ID': field, 'DATA_DESC_ID':dd}}
ms = ftab.query('DATA_DESC_ID==%d' % dd, style='')
assert ms.nrows() > 0, "Empty selection for FIELD_ID=%d and DATA_DESC_ID=%d" % (field, dd)
log.debug("create_blockvisibility_from_ms: Found %d rows" % (ms.nrows()))
# The TIME column has descriptor:
# {'valueType': 'double', 'dataManagerType': 'IncrementalStMan', 'dataManagerGroup': 'TIME',
# 'option': 0, 'maxlen': 0, 'comment': 'Modified Julian Day',
# 'keywords': {'QuantumUnits': ['s'], 'MEASINFO': {'type': 'epoch', 'Ref': 'UTC'}}}
otime = ms.getcol('TIME')
datacol = ms.getcol(datacolumn, nrow=1)
datacol_shape = list(datacol.shape)
channels = datacol.shape[-2]
log.debug("create_blockvisibility_from_ms: Found %d channels" % (channels))
if channum is None:
if start_chan is not None and end_chan is not None:
try:
log.debug("create_blockvisibility_from_ms: Reading channels from %d to %d" %
(start_chan, end_chan))
print("create_blockvisibility_from_ms: Reading channels from %d to %d (inclusive)" %
(start_chan, end_chan))
blc = [start_chan, 0]
trc = [end_chan, datacol_shape[-1] - 1]
channum = range(start_chan, end_chan+1)
ms_vis = ms.getcolslice(datacolumn, blc=blc, trc=trc)
ms_weight = ms.getcol('WEIGHT')
except IndexError:
raise IndexError("channel number exceeds max. within ms")
else:
log.debug("create_blockvisibility_from_ms: Reading all %d channels" % (channels))
try:
channum = range(channels)
ms_vis = ms.getcol(datacolumn)[:, channum, :]
ms_weight = ms.getcol('WEIGHT')
channum = range(channels)
except IndexError:
raise IndexError("channel number exceeds max. within ms")
else:
log.debug("create_blockvisibility_from_ms: Reading channels %s " % (channum))
channum = range(channels)
try:
ms_vis = ms.getcol(datacolumn)[:, channum, :]
ms_weight = ms.getcol('WEIGHT')[:, :]
except IndexError:
raise IndexError("channel number exceeds max. within ms")
uvw = -1 * ms.getcol('UVW')
antenna1 = ms.getcol('ANTENNA1')
antenna2 = ms.getcol('ANTENNA2')
integration_time = ms.getcol('INTERVAL')
# time = Time((time-integration_time/2.0)/86400+ 2400000.5,format='jd',scale='utc').utc.value
time = (otime - integration_time / 2.0)
start_time = numpy.min(time)/86400.0
end_time = numpy.max(time)/86400.0
log.debug("create_blockvisibility_from_ms: Observation from %s to %s" %
(Time(start_time, format='mjd').iso, Time(end_time, format='mjd').iso))
# Now get info from the subtables
spwtab = table('%s/SPECTRAL_WINDOW' % msname, ack=False)
cfrequency = spwtab.getcol('CHAN_FREQ')[dd][channum]
cchannel_bandwidth = spwtab.getcol('CHAN_WIDTH')[dd][channum]
nchan = cfrequency.shape[0]
# Get polarisation info
npol = 4
poltab = table('%s/POLARIZATION' % msname, ack=False)
corr_type = poltab.getcol('CORR_TYPE')
# These correspond to the CASA Stokes enumerations
if numpy.array_equal(corr_type[0], [1, 2, 3, 4]):
polarisation_frame = PolarisationFrame('stokesIQUV')
elif numpy.array_equal(corr_type[0], [5, 6, 7, 8]):
polarisation_frame = PolarisationFrame('circular')
elif numpy.array_equal(corr_type[0], [9, 10, 11, 12]):
polarisation_frame = PolarisationFrame('linear')
elif numpy.array_equal(corr_type[0], [9]):
npol = 1
polarisation_frame = PolarisationFrame('stokesI')
else:
raise KeyError("Polarisation not understood: %s" % str(corr_type))
# Get configuration
anttab = table('%s/ANTENNA' % msname, ack=False)
nants = anttab.nrows()
mount = anttab.getcol('MOUNT')
names = anttab.getcol('NAME')
diameter = anttab.getcol('DISH_DIAMETER')
xyz = anttab.getcol('POSITION')
configuration = Configuration(name='', data=None, location=None,
names=names, xyz=xyz, mount=mount, frame=None,
receptor_frame=ReceptorFrame("linear"),
diameter=diameter)
# Get phasecentres
fieldtab = table('%s/FIELD' % msname, ack=False)
pc = fieldtab.getcol('PHASE_DIR')[field, 0, :]
source = fieldtab.getcol('NAME')[field]
phasecentre = SkyCoord(ra=pc[0] * u.rad, dec=pc[1] * u.rad, frame='icrs', equinox='J2000')
time_index_row = numpy.zeros_like(time, dtype='int')
time_last = time[0]
time_index = 0
for row, _ in enumerate(time):
if time[row] > time_last + integration_time[row]:
assert time[row] > time_last, "MS is not time-sorted - cannot convert"
time_index += 1
time_last = time[row]
time_index_row[row] = time_index
ntimes = time_index + 1
bv_times = numpy.zeros([ntimes])
bv_vis = numpy.zeros([ntimes, nants, nants, nchan, npol]).astype('complex')
bv_weight = numpy.zeros([ntimes, nants, nants, nchan, npol])
bv_imaging_weight = numpy.zeros([ntimes, nants, nants, nchan, npol])
bv_uvw = numpy.zeros([ntimes, nants, nants, 3])
bv_integration_time = numpy.zeros([ntimes])
for row, _ in enumerate(time):
time_index = time_index_row[row]
bv_times[time_index] = time[row]
bv_vis[time_index, antenna2[row], antenna1[row], ...] = ms_vis[row, ...]
bv_weight[time_index, antenna2[row], antenna1[row], :, ...] = ms_weight[row, numpy.newaxis, ...]
bv_imaging_weight[time_index, antenna2[row], antenna1[row], :, ...] = ms_weight[row, numpy.newaxis, ...]
bv_uvw[time_index, antenna2[row], antenna1[row], :] = uvw[row, :]
bv_integration_time[time_index] = integration_time[row]
vis_list.append(BlockVisibility(uvw=bv_uvw,
time=bv_times,
frequency=cfrequency,
channel_bandwidth=cchannel_bandwidth,
vis=bv_vis,
weight=bv_weight,
integration_time = bv_integration_time,
imaging_weight=bv_imaging_weight,
configuration=configuration,
phasecentre=phasecentre,
polarisation_frame=polarisation_frame,
source=source, meta=meta))
tab.close()
return vis_list
def __initData(self):
"""Private function to generate a random set of data for writing a UVFITS
file. The data is returned as a dictionary with keys:
* freq - frequency array in Hz
* site - Observatory object
* stands - array of stand numbers
* bl - list of baseline pairs in real stand numbers
* vis - array of visibility data in baseline x freq format
"""
if run_ms_tests == False:
return
# Frequency range
freq = numpy.arange(0, 512) * 20e6 / 512 + 40e6
channel_width = numpy.full_like(freq, 20e6 / 512.)
# Site and stands
obs = EarthLocation(lon="116.76444824",
lat="-26.824722084",
height=300.0)
mount = numpy.array([
'equat', 'equat', 'equat', 'equat', 'equat', 'equat', 'equat',
'equat', 'equat', 'equat'
])
names = numpy.array([
'ak02', 'ak04', 'ak05', 'ak12', 'ak13', 'ak14', 'ak16', 'ak24',
'ak28', 'ak30'
])
diameter = numpy.array(
[12., 12., 12., 12., 12., 12., 12., 12., 12., 12.])
xyz = numpy.array(
[[-2556109.98244348, 5097388.70050131, -2848440.1332423],
[-2556087.396082, 5097423.589662, -2848396.867933],
[-2556028.60254059, 5097451.46195695, -2848399.83113161],
[-2556496.23893101, 5097333.71466669, -2848187.33832738],
[-2556407.35299627, 5097064.98390756, -2848756.02069474],
[-2555972.78456557, 5097233.65481756, -2848839.88915184],
[-2555592.88867802, 5097835.02121109, -2848098.26409648],
[-2555959.34313275, 5096979.52802882, -2849303.57702486],
[-2556552.97431815, 5097767.23612874, -2847354.29540396],
[-2557348.40370367, 5097170.17682775, -2847716.21368966]])
site_config = Configuration(name='ASKAP',
data=None,
location=obs,
names=names,
xyz=xyz,
mount=mount,
frame=None,
receptor_frame=ReceptorFrame("linear"),
diameter=diameter)
antennas = []
for i in range(len(names)):
antennas.append(
Antenna(i, Stand(names[i], xyz[i, 0], xyz[i, 1], xyz[i, 2])))
# Set baselines and data
blList = []
N = len(antennas)
antennas2 = antennas
for i in range(0, N - 1):
for j in range(i + 1, N):
blList.append((antennas[i], antennas2[j]))
visData = numpy.random.rand(len(blList), len(freq))
visData = visData.astype(numpy.complex64)
return {
'freq': freq,
'channel_width': channel_width,
'site': site_config,
'antennas': antennas,
'bl': blList,
'vis': visData
}
def __initData_WGS84(self):
"""Private function to generate a random set of data for writing a Measurements
file. The data is returned as a dictionary with keys:
* freq - frequency array in Hz
* site - observatory object
* stands - array of stand numbers
* bl - list of baseline pairs in real stand numbers
* vis - array of visibility data in baseline x freq format
"""
if run_ms_tests == False:
return
# Frequency range
freq = numpy.arange(0, 512) * 20e6 / 512 + 40e6
channel_width = numpy.full_like(freq, 20e6 / 512.)
# Site and stands
obs = EarthLocation(lon="+116.6356824",
lat="-26.70130064",
height=377.0)
names = numpy.array(['A%02d' % i for i in range(36)])
mount = numpy.array(['equat' for i in range(36)])
diameter = numpy.array([12 for i in range(36)])
xyz = numpy.array([[-175.233429, +1673.460938, 0.0000],
[+261.119019, +796.922119, 0.0000],
[-29.2005200, +744.432068, 0.0000],
[-289.355286, +586.936035, 0.0000],
[-157.031570, +815.570068, 0.0000],
[-521.311646, +754.674927, 0.0000],
[-1061.114258, +840.541443, 0.0000],
[-921.829407, +997.627686, 0.0000],
[-818.293579, +1142.272095, 0.0000],
[-531.752808, +850.726257, 0.0000],
[+81.352448, +790.245117, 0.0000],
[+131.126358, +1208.831909, 0.0000],
[-1164.709351, +316.779236, 0.0000],
[-686.248901, +590.285278, 0.0000],
[-498.987305, +506.338226, 0.0000],
[-182.249146, +365.113464, 0.0000],
[+420.841858, +811.081543, 0.0000],
[+804.107910, +1273.328369, 0.0000],
[-462.810394, +236.353790, 0.0000],
[-449.772339, +15.039755, 0.0000],
[+13.791821, +110.971809, 0.0000],
[-425.687317, -181.908752, 0.0000],
[-333.404053, -503.603394, 0.0000],
[-1495.472412, +1416.063232, 0.0000],
[-1038.578857, +1128.367920, 0.0000],
[-207.151749, +956.312561, 0.0000],
[-389.051880, +482.405670, 0.0000],
[-434.000000, +510.000000, 0.0000],
[-398.000000, +462.000000, 0.0000],
[-425.000000, +475.000000, 0.0000],
[-400.000000, +3664.000000, 0.0000],
[+1796.000000, +1468.000000, 0.0000],
[+2600.000000, -1532.000000, 0.0000],
[-400.000000, -2336.000000, 0.0000],
[-3400.00000, -1532.000000, 0.0000],
[-2596.000000, +1468.000000, 0.0000]])
site_config = Configuration(name='ASKAP',
data=None,
location=obs,
names=names,
xyz=xyz,
mount=mount,
frame=None,
receptor_frame=ReceptorFrame("linear"),
diameter=diameter)
antennas = []
for i in range(len(names)):
antennas.append(
Antenna(i, Stand(names[i], xyz[i, 0], xyz[i, 1], xyz[i, 2])))
# Set baselines and data
blList = []
N = len(antennas)
antennas2 = antennas
for i in range(0, N - 1):
for j in range(i + 1, N):
blList.append((antennas[i], antennas2[j]))
visData = numpy.random.rand(len(blList), len(freq))
visData = visData.astype(numpy.complex64)
return {
'freq': freq,
'channel_width': channel_width,
'site': site_config,
'antennas': antennas,
'bl': blList,
'vis': visData
}