def get_model_radius(model):
"""
extracts radius for extended source
:param model: ~gammalib.GModelSky
:return: radius: float
"""
try:
if model.spatial().type() == 'DiffuseMapCube':
# region not implemented in gammalib, extract manually extent of the map
# call the energies method to load the cube
model.spatial().energies()
# half size along x direction
slice = model.spatial().cube().extract(0)
ctr_pix = gammalib.GSkyPixel((slice.nx() - 1) / 2,
(slice.ny() - 1) / 2)
ctr_dir = slice.pix2dir(ctr_pix)
bor_pix = gammalib.GSkyPixel(0., (slice.ny() - 1) / 2)
bor_dir = slice.pix2dir(bor_pix)
radius = bor_dir.dist_deg(ctr_dir)
else:
circle = gammalib.GSkyRegionCircle(model.spatial().region())
radius = circle.radius()
except:
print('Cannot extract radius for model {} with spatial model type {}'.
format(model.name(),
model.spatial().type()))
return radius
def _get_parameters_bkgmethod_reflected(self):
"""
Get parameters for REFLECTED background method
"""
# Get source shape
self._srcshape = self['srcshape'].string()
# Set source region (so far only CIRCLE is supported)
if self._srcshape == 'CIRCLE':
# Query source direction
self._query_src_direction()
# Query minimum number of background regions and number of
# background regions to skip next to On region
self['bkgregmin'].integer()
self['bkgregskip'].integer()
# Set circular source region
self._rad = self['rad'].real()
self._src_reg.append(
gammalib.GSkyRegionCircle(self._src_dir, self._rad))
# Query usage of background model
self['use_model_bkg'].boolean()
# Return
return
def set_map(obsdef, radius=2.0):
"""
Set map from observation definition dictionary
Parameters
----------
obsdef : list of dict
List of pointing definitions
"""
# Create sky map
map = gammalib.GSkyMap('CAR', 'GAL', 340.0, 0.0, -0.1, 0.1, 950, 100)
# Loop over observations
for obs in obsdef:
# Set sky region
centre = gammalib.GSkyDir()
centre.lb_deg(obs['lon'], obs['lat'])
circle = gammalib.GSkyRegionCircle(centre, radius)
region = gammalib.GSkyRegionMap(circle)
exposure = region.map().copy()
exposure *= obs['duration']/3600.0
# Add sky region
map += exposure
# Return map
return map
def _reflected_regions(self, obs):
"""
Calculate list of reflected regions for a single observation (pointing)
Parameters
----------
obs : `~gammalib.GCTAObservation()`
CTA observation
Returns
-------
regions : `~gammalib.GSkyRegions`
List of reflected regions
"""
# Initialise list of reflected regions
regions = gammalib.GSkyRegions()
# Get offset angle of source
pnt_dir = obs.pointing().dir()
offset = pnt_dir.dist_deg(self._src_dir)
# Skip observation if it is too close to source
if offset <= self._rad:
msg = ' Skip because observation is pointed at %.3f deg <= '\
'"rad=%.3f" from source.' \
% (offset, self._rad)
self._log_string(gammalib.NORMAL, msg)
# Skip observation if it is pointed too far from the source
elif offset >= self['maxoffset'].real():
msg = ' Skip because observation is pointed at %.3f deg >= '\
'"maxoffset=%.3f" from source.' \
% (offset, self['maxoffset'].real())
self._log_string(gammalib.NORMAL, msg)
# ... otherwise
else:
posang = pnt_dir.posang_deg(self._src_dir)
if self._srcshape == 'CIRCLE':
# Determine number of background regions to skip
N_skip = self['bkgregskip'].integer()
N_start = 1 + N_skip
N_lim = 1 + 2 * N_skip
# Compute the angular separation of reflected regions wrt
# camera center. The factor 1.05 ensures background regions
# do not overlap due to numerical precision issues
alpha = 1.05 * 2.0 * self._rad / offset
# Compute number of reflected regions by dividing the angular
# separation by 2 pi.
N = int(2.0 * math.pi / alpha)
# If there are not enough reflected regions then skip the
# observation ...
if N < self['bkgregmin'].integer() + N_lim:
msg = ' Skip because the number %d of reflected regions '\
'for background estimation is smaller than '\
'"bkgregmin"=%d.' % (N-N_lim, self['bkgregmin'].integer())
self._log_string(gammalib.NORMAL, msg)
# ... otherwise loop over position angle to create reflected
# regions
else:
# Log appending of reflected regions
msg = ' Use %d reflected regions.' % (N - N_lim)
self._log_string(gammalib.NORMAL, msg)
# Append reflected regions
alpha = 360.0 / N
for s in range(N_start, N - N_skip):
dphi = s * alpha
ctr_dir = pnt_dir.clone()
ctr_dir.rotate_deg(posang + dphi, offset)
region = gammalib.GSkyRegionCircle(ctr_dir, self._rad)
if self._has_exclusion:
if self._excl_reg.overlaps(region):
msg = ' Reflected region overlaps with '\
'exclusion region.'
self._log_string(gammalib.EXPLICIT, msg)
else:
regions.append(region)
else:
regions.append(region)
# Return reflected regions
return regions
# Extracting free parameters
freepars = [ par.name() for par in models[ args.gname ].spectral() \
if par.is_free() ]
# Set the GSkydir for pointing direction and source position
pdir = gammalib.GSkyDir()
rdir = gammalib.GSkyDir()
pdir.radec_deg(args.pntra, args.pntdec)
rdir.radec_deg(args.ROIra, args.ROIdec)
# Compute angular distance between directions
dirs_sep = pdir.dist_deg(rdir)
# Creating two GSkyRegionCircle regions to check that
# Region of simulation contains ROI region
pntregion = gammalib.GSkyRegionCircle(pdir, args.pntradius)
roiregion = gammalib.GSkyRegionCircle(rdir, args.ROIradius)
# Check if pointing region contains ROI region
is_inside = pntregion.contains(roiregion)
if is_inside:
print(("\n\nPonting region with:\n" +
"\tRA : {:.3f} deg\n".format(args.pntra) +
"\tDec : {:.3f} deg\n".format(args.pntdec) +
"\tRadius : {:.2f} deg\n\n".format(args.pntradius) +
"contains ROI region.\n\nROI region:\n" +
"\tRA : {:.3f} deg\n".format(args.ROIra) +
"\tDec : {:.3f} deg\n".format(args.ROIdec) +
"\tRadius : {:.2f} deg".format(args.ROIradius) +
def _select_model(self, model, obs):
"""
Select model
Parameters
----------
model : `~gammalib.GModel`
Model
obs : `~gammalib.GObservations`
Observation container
Returns
-------
select : bool
Model selection flag
"""
# Get selection parameters
roilimit = self['roilimit'].real()
roimargin = self['roimargin'].real()
ethres = self['ethres'].real()
fluxlimit = self['fluxlimit'].real()
tslimit = self['tslimit'].real()
# Initialise selection flag to True
select = True
msg = 'Select by default'
# If the model has a spatial component then check of overlap
if hasattr(model, 'spatial'):
# Determine the model bounding box
model_bounds = model.spatial().region()
# Initialise with an unselect model
select = False
msg = 'Exclude since outside any RoI'
# Loop over all observations and check whether the model falls
# into one of them
for o in obs:
# Get RoI centre and radius. The RoI radius is limited by
# roilimit. A margin given by roimargin is added to the RoI
# radius.
#obs_centre = o.roi().centre().dir() # Segmentation fault
#obs_radius = o.roi().radius() # Segmentation fault
obs_roi = o.roi()
obs_centre = obs_roi.centre().dir()
obs_radius = obs_roi.radius()
if obs_radius > roilimit:
obs_radius = roilimit
obs_radius += roimargin
# Set circular sky region
obs_bounds = gammalib.GSkyRegionCircle(obs_centre, obs_radius)
# If model overlaps with RoI then signal overlap
if obs_bounds.overlaps(model_bounds):
select = True
msg = 'Select due to overlap with at least one RoI'
break
# If model is selected and if model has a TS value then apply TS
# selection
if select and model.has_ts():
if model.ts() < tslimit:
select = False
msg = 'Exclude since below TS limit (TS=%.3f)' % model.ts()
# If model is selected and if model is a sky model then apply flux
# limit selection
if select and model.classname() == 'GModelSky':
emin = gammalib.GEnergy(ethres, 'TeV')
emax = gammalib.GEnergy(1000.0, 'TeV')
flux = model.spectral().flux(emin, emax)
if flux < fluxlimit:
select = False
msg = 'Exclude since below flux limit (Flux=%.3e ph/cm2/s)' % flux
# Log model selection
self._log_value(gammalib.NORMAL, model.name(), msg)
# Return selection flag
return select
