def get_skymodel(self, freq=None):
"""
"""
sky = Table.read(self.skymodel_file)
all_coords = radec(sky['ra'], sky['dec'])
phase_center = radec(self.ra, self.dec)
sep = all_coords.separation(phase_center).deg
infield_mask = sep <= self.radius
infield_sky = sky[infield_mask]
flux = self._extrapol_spec(freq=freq,
rflux=infield_sky['flux'],
rfreq=infield_sky['rfreq'],
index=infield_sky['index'])
fluxmask = flux >= self.cutoff
infield_sky = infield_sky[fluxmask]
flux = flux[fluxmask]
names = np.zeros(len(infield_sky), dtype=str)
skymodel = np.zeros((len(infield_sky), 3))
for i in range(len(infield_sky)):
names[i] = infield_sky['name'][i]
skymodel[i, 0] = flux[i]
skymodel[i, 1] = infield_sky['ra'][i]
skymodel[i, 2] = infield_sky['dec'][i]
return skymodel, names
def _ateam_in_fov(self):
"""
"""
at = ateam()
infield = {}
for key in at.keys():
src_radec = radec(ra=at[key][0], dec=at[key][1])
sep = self.center.separation(src_radec).deg
if sep <= self.radius:
infield[key] = src_radec
return infield
def __init__(self, center, radius, freq, method='gsm', cutoff=100.):
self.center = radec(ra=center[0], dec=center[1])
self.radius = radius
self.frequency = freq
self.cutoff = cutoff # in Jy
if method.lower() == 'manual':
self.sources = self._ateam_in_fov()
self.fluxes = self._ateam_flux()
for key in self.sources['key']:
if self.fluxes[key] < self.cutoff:
del self.sources[key]
del self.fluxes[key]
elif method.lower() == 'gsm':
self.gsmfile = ''
self.sources, self.fluxes = self.from_gsm()
def from_gsm(self):
""" NEED TO EXTRAPOLATE AT THE RIGHT FREQUENCY
CURRENTLY OK FOR 60 MHz
"""
if not isfile(self.gsmfile):
self.save_from_gsm()
infield = {}
command = [
'https://lcs165.lofar.eu/cgi-bin/gsmv1.cgi?',
'coord=' + str(self.center.ra.deg),
',' + str(self.center.dec.deg),
'&radius=' + str(self.radius),
'&cutoff=' + str(self.cutoff),
'&unit=deg&deconv=y',
]
url = ''.join(command)
with urlopen(url) as response:
response = response.read().decode('utf8')
sources = response.split('\n')[3:]
infield = {}
fluxes = {}
for source in sources:
if source == '':
continue
src_desc = source.split(', ')
src_name = src_desc[0]
fluxes[src_name] = float(src_desc[4])
src = radec_hd(src_desc[2] + ' ' +
src_desc[3].replace('.', ':', 2))
infield[src_name] = radec(ra=src.ra.deg, dec=src.dec.deg)
ref_freq = float(src_desc[8]) if src_desc[8] != '' else 60e6
spec_index = float(src_desc[9].replace('[', '').replace(']', ''))
return infield, fluxes