Пример #1
0
class PointSource(object):
    """ combine name, skydir, model """
    def __init__(self,
                 skydir,
                 name,
                 model=None,
                 free_parameters=True,
                 leave_parameters=False):
        self.name = name
        self.skydir = skydir
        self.model = PowerLaw() if model is None else model
        #if not free_parameters:
        if not leave_parameters:
            for i in xrange(len(self.model.free)):
                self.model.free[i] = free_parameters
        self.duplicate = False

    def __str__(self):
        return '\n'.join([
            '\n',
            '=' * 60,
            'Name:\t\t%s' % (self.name),
            'R.A. (J2000):\t%.5f' % (self.skydir.ra()),
            'Dec. (J2000):\t%.5f' % (self.skydir.dec()),
            'Model:\t\t%s' % (self.model.full_name()),
            '\t' + self.model.__str__(indent='\t'),
        ])

    def copy(self):
        """ Create a deep copy of the point source. """
        return PointSource(SkyDir(self.skydir.ra(), self.skydir.dec()),
                           self.name,
                           self.model.copy(),
                           leave_parameters=True)
Пример #2
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    def get_default_sources(self):

        point_sources, diffuse_sources = [], []

        model = PowerLaw(index=self.powerlaw_index, e0=np.sqrt(self.emin*self.emax))
        model.set_flux(self.flux, emin=self.emin, emax=self.emax)
        ps = PointSource(
            name = 'source',
            model = model.copy(),
            skydir = self.roi_dir)
        point_sources.append(ps)

        if self.isotropic_bg:
            ds = get_sreekumar()
            diffuse_sources.append(ds)

        if self.nearby_source:
            ps = PointSource(
                name = 'nearby_source',
                model = model.copy(),
                skydir = SkyDir(self.roi_dir.ra(),self.roi_dir.dec()+3)
            )
            point_sources.append(ps)

        return point_sources, diffuse_sources
Пример #3
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    def _calculate(self):
        self.results = dict()

        energies = np.logspace(np.log10(self.emin),np.log10(self.emax),self.npoints)

        if self.e0 is None: 
            self.e0=np.sqrt(self.emin*self.emax)

        self.results['input_model'] = spectrum_to_dict(self.input_model)
        self.results['dnde'] = dnde = self.input_model(energies)

        self.pl_model = PowerLaw(e0=self.e0)
        self.pl_model.set_flux(self.input_model.i_flux(emin=self.emin,emax=self.emax),
                    emin=self.emin,emax=self.emax)

        def residuals(args):
            norm,index=args
            self.pl_model['norm']=norm
            self.pl_model['index']=index
            dnde_pl = self.pl_model(energies)
            #return np.sum((np.log(dnde) - np.log(dnde_pl))**2)
            print (np.log10(dnde)-np.log10(dnde_pl))**2
            return np.sum((np.log(dnde) - np.log(dnde_pl))**2)
            #return np.sum((dnde - dnde_pl)**2)

        best_norm,best_index=fmin(residuals,[self.pl_model['norm'],self.pl_model['index']])
        self.pl_model['norm']=best_norm
        self.pl_model['index']=best_index

        self.results['pl_model'] = spectrum_to_dict(self.pl_model)
Пример #4
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 def __init__(self,skydir,name,model=None,free_parameters=True,leave_parameters=False):
     self.name    = name
     self.skydir = skydir
     self.model  = PowerLaw() if model is None else model
     #if not free_parameters:
     if not leave_parameters:
         for i in xrange(len(self.model.free)): self.model.free[i] = free_parameters
     self.duplicate = False
Пример #5
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 def estimate_flux(dnde, energy, emin, emax, e_weight):
     """ estimate the emin to emax flux for a source with prefactor
         dnde at the given energy. assuming the source has a
         spectral index of 2. 
         
         Note, for our situation dnde has units [ph/cm^2/s/TeV]
         and energy has units [TeV], but the ouptut of the
         i_flux function is correct. If e_weight=0,
         the return has units [ph/cm^2/s]. If e_weight=1,
         the return has units [TeV/cm^2/s]. """
     model = PowerLaw(index=2, norm=dnde, e0=energy)
     return model.i_flux(emin=emin, emax=emax, e_weight=e_weight)
Пример #6
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 def estimate_flux(dnde,energy,emin,emax, e_weight):
     """ estimate the emin to emax flux for a source with prefactor
         dnde at the given energy. assuming the source has a
         spectral index of 2. 
         
         Note, for our situation dnde has units [ph/cm^2/s/TeV]
         and energy has units [TeV], but the ouptut of the
         i_flux function is correct. If e_weight=0,
         the return has units [ph/cm^2/s]. If e_weight=1,
         the return has units [TeV/cm^2/s]. """
     model = PowerLaw(index=2, norm=dnde, e0=energy)
     return model.i_flux(emin=emin, emax=emax, e_weight=e_weight)
Пример #7
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def get_sreekumar(diff_factor=1, free=(True, False)):

    # use Sreekumar-like defaults
    if diff_factor == 1:
        name = 'Sreekumar Isotropic'
    else:
        name = 'Sreekumar Isotropic x%s' % diff_factor

    free = np.asarray(free).copy()
    model = PowerLaw(index=2.1, free=free)
    model.set_flux(1.5e-5*diff_factor, emin=100, emax=np.inf)

    return DiffuseSource(
        name=name,
        diffuse_model=IsotropicConstant(),
        scaling_model=model)
Пример #8
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    def get_source(name, position, 
                   fit_emin, fit_emax, 
                   extended=False, sigma=None):
        """ build a souce. """
        model=PowerLaw(index=2, e0=np.sqrt(fit_emin*fit_emax))
        PWNRegion.limit_powerlaw(model)
        flux=PowerLaw(norm=1e-11, index=2, e0=1e3).i_flux(fit_emin,fit_emax)
        model.set_flux(flux,emin=fit_emin,emax=fit_emax)

        if extended and sigma != 0:
            if not isnum(sigma): raise Exception("sigma must be set. """)
            return ExtendedSource(
                name=name,
                model=model,
                spatial_model=Gaussian(sigma=sigma, center=position))
        else:
            return PointSource(
                name=name,
                model=model,
                skydir=position)
Пример #9
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    def get_source(name,
                   position,
                   fit_emin,
                   fit_emax,
                   extended=False,
                   sigma=None):
        """ build a souce. """
        model = PowerLaw(index=2, e0=np.sqrt(fit_emin * fit_emax))
        PWNRegion.limit_powerlaw(model)
        flux = PowerLaw(norm=1e-11, index=2, e0=1e3).i_flux(fit_emin, fit_emax)
        model.set_flux(flux, emin=fit_emin, emax=fit_emax)

        if extended and sigma != 0:
            if not isnum(sigma): raise Exception("sigma must be set. " "")
            return ExtendedSource(name=name,
                                  model=model,
                                  spatial_model=Gaussian(sigma=sigma,
                                                         center=position))
        else:
            return PointSource(name=name, model=model, skydir=position)
Пример #10
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    def __init__(self, **kwargs):
        """ Make the naming consistent with the PointSource object so that
            extended sources 'feel' like point sources.

            """
        keyword_options.process(self, kwargs)

        if self.model == None: self.model = PowerLaw()
        if self.spatial_model == None: self.spatial_model = Disk()

        if not isinstance(self.spatial_model, SpatialModel):
            raise Exception(
                "The diffuse_model passed to an Extended Source must inherit from SpatialModel."
            )

        super(ExtendedSource, self).__init__(diffuse_model=self.spatial_model,
                                             scaling_model=self.model,
                                             name=self.name)

        self.model.background = False
Пример #11
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def build_roi(name, snrdata, latdata):

    snrdata=loaddict(snrdata)
    latdata=loaddict(latdata)

    roi_dir = SkyDir(*snrdata[name]['cel'])
    snrsize = snrdata[name]['size']

    if isinstance(snrsize,list) and len(snrsize) == 2:
        snrradius = math.sqrt(snrsize[0]*snrsize[1])/2.0
    else:
        snrradius = snrsize/2.0

    ds = DataSpecification(**latdata['data'])

    sa = SpectralAnalysis(ds,
                          binsperdec = 4,
                          emin       = 1e4,
                          emax       = 10**5.5,
                          irf        = "P7SOURCE_V6",
                          roi_dir    = roi_dir,
                          maxROI     = 10,
                          minROI     = 10,
                          event_class= 0)


    diffuse_sources = get_default_diffuse(**latdata['diffuse'])

    catalog = Catalog2FGL(**latdata['catalog'])

    roi=sa.roi(point_sources=[],
               diffuse_sources=diffuse_sources,
               catalogs=catalog)

    print 'bins',roi.bin_edges

    for source in roi.get_sources():
        if np.degrees(source.skydir.difference(roi_dir)) < snrradius + 0.5:
            roi.del_source(source)

    snr = ExtendedSource(
        name = name,
        model = PowerLaw(),
        spatial_model = Disk(sigma=snrradius, center=roi_dir)
    )

    roi.add_source(snr)

    return roi
Пример #12
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    def test_ps1(self):

        if PointlikeTest.VERBOSE:
            print '\nAnalyze a simulated point source against the galactic + isotropic diffuse\n'

        center = SkyDir(0, 0)

        diffuse_sources = get_default_diffuse(
            diffdir='$GLAST_EXT/diffuseModels/v2r0p1/',
            gfile='ring_2year_P76_v0.fits',
            ifile='isotrop_2year_P76_source_v1.txt')

        model = PowerLaw(index=2)
        model.set_flux(1e-6)
        ps_mc = PointSource(name='source', skydir=center, model=model)
        ps_fit = ps_mc.copy()
        point_sources = [ps_fit]

        roi = PointlikeTest.get_roi('ps1', center, point_sources,
                                    diffuse_sources)
        global roi_pt
        roi_pt = roi  # helps with debugging

        if PointlikeTest.VERBOSE:
            print roi

        roi.fit(use_gradient=PointlikeTest.USE_GRADIENT)
        if PointlikeTest.VERBOSE: print roi
        roi.localize(update=True)
        roi.fit(use_gradient=PointlikeTest.USE_GRADIENT)
        if PointlikeTest.VERBOSE:
            roi.print_summary()
            print roi

        self.compare_model(ps_fit, ps_mc)
        self.compare_spatial_model(ps_fit, ps_mc, roi.lsigma)
Пример #13
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def fix_bad_cutoffs(roi, exclude_names):
    """ Loop over all sources. When ExpCutoff souce has cutoff>10TeV, convert to powerlaw. """
    any_changed = False
    for source in roi.get_sources():
        if source.name in exclude_names: continue

        model = source.model

        if np.any(model.free) and isinstance(
                model, ExpCutoff) and model['cutoff'] > 1e7:
            print 'Converting cutoff source %s to powerlaw because cutoff too high' % source.name
            new_model = PowerLaw(norm=model['norm'],
                                 index=model['index'],
                                 e0=model.e0)

            any_changed = True
            roi.modify(which=source, model=new_model, keep_old_flux=False)
    return any_changed
Пример #14
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    def get_gal(component, free=True):
        if version == 1:
            gfile_base = '%s_z%s_Ts%s_v%s_mapcube_fixed_' % (dist, halo, TS,
                                                             version)
        elif version == 2:
            gfile_base = '%s_z%s_Ts%s_v%s_mapcube_' % (dist, halo, TS, version)
        filename = join(diffdir, gfile_base + component + '.fits.gz')
        if verbosity: print ' * Loading file %s' % filename

        if not exists(filename):
            raise Exception("File %s does not exist." % filename)

        gmodel = PowerLaw(norm=1, index=0) if fit_index else Constant()
        ds = get_diffuse_source('MapCubeFunction',
                                filename,
                                gmodel,
                                None,
                                name=component)
        ds.smodel.free[:] = free
        return ds
Пример #15
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    def _compute(self):
        if self.verbosity: 
            print 'Calculating pointlike upper limit'

        roi = self.roi
        name = self.name

        saved_state = PointlikeState(roi)

        """ Note keep old flux, because it is important to have
            the spectral model pushed into the upper_limit
            code reasonably close to the best fit flux. This
            is because initial likelihood (ll_0) is used to scale
            the likelihood so it has to be reasonably close to 
            the best value. """
        model = PowerLaw(index=self.powerlaw_index)
        roi.modify(which=name, model=model, keep_old_flux=True)

        super(PointlikePowerLawUpperLimit,self)._compute()

        saved_state.restore(just_spectra=True)
Пример #16
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    def test_ff(self):
        """ Simulate from a filefunction object and test that the best
        fit flux
            is consistent with the simulated flux. """
        name = 'ff'

        model = PowerLaw(index=2)
        model.set_flux(1e-6)
        simdir = path.expand('$SIMDIR/%s' % name)
        if not os.path.exists(simdir):
            os.makedirs(simdir)

        filename = abspath(join(simdir, 'file_function.txt'))
        model.save_profile(filename, 10, 1e6)
        ff = FileFunction(file=filename)

        center = SkyDir(0, 0)
        ps = PointSource(name='source', skydir=center, model=ff)
        point_sources = [ps]
        diffuse_sources = None
        roi = PointlikeTest.get_roi(name,
                                    center,
                                    point_sources,
                                    diffuse_sources,
                                    emin=1e2,
                                    emax=1e5,
                                    binsperdec=4)

        if PointlikeTest.VERBOSE:
            roi.print_summary()
            print roi

        roi.fit(use_gradient=PointlikeTest.USE_GRADIENT)

        if PointlikeTest.VERBOSE:
            roi.print_summary()
            print roi

        fit, error = ff.i_flux(1e2, 1e5, error=True)
        true = model.i_flux(1e2, 1e5, error=False)
        self.assertPull(fit, true, error, 'flux')
Пример #17
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    def get_default_sources(self):

        point_sources, diffuse_sources = [], []

        model = PowerLaw(index=self.powerlaw_index,
                         e0=np.sqrt(self.emin * self.emax))
        model.set_flux(self.flux, emin=self.emin, emax=self.emax)
        ps = PointSource(name='source',
                         model=model.copy(),
                         skydir=self.roi_dir)
        point_sources.append(ps)

        if self.isotropic_bg:
            ds = get_sreekumar()
            diffuse_sources.append(ds)

        if self.nearby_source:
            ps = PointSource(name='nearby_source',
                             model=model.copy(),
                             skydir=SkyDir(self.roi_dir.ra(),
                                           self.roi_dir.dec() + 3))
            point_sources.append(ps)

        return point_sources, diffuse_sources
Пример #18
0
    def _calculate(self):
        like = self.like
        name = self.name

        if self.verbosity: print 'Testing cutoff in gtlike'

        saved_state = SuperState(like)

        emin, emax = get_full_energy_range(like)

        self.results = d = dict(
            energy = energy_dict(emin=emin, emax=emax, energy_units=self.energy_units)
        )

        try:

            def get_flux():
                return like.flux(name, emin, emax)

            def spectrum():
                source = like.logLike.getSource(name)
                s=source.spectrum()
                return spectrum_to_dict(s, errors=True)

            old_flux = get_flux()

            if spectrum()['name'] == 'PowerLaw':
                pass
            else:
                powerlaw_model=PowerLaw(norm=1e-11, index=2, e0=np.sqrt(emin*emax))
                powerlaw_model.set_flux(old_flux,emin=emin,emax=emax)
                powerlaw_model.set_default_limits(oomp_limits=True)

                if self.verbosity: print 'powerlaw_model is',powerlaw_model

                powerlaw_spectrum=build_gtlike_spectrum(powerlaw_model)
                like.setSpectrum(name,powerlaw_spectrum)

            if self.verbosity: 
                print 'About to fit powerlaw_spectrum'
                print summary(like)

            paranoid_gtlike_fit(like, verbosity=self.verbosity)

            if self.verbosity: 
                print 'Done fitting powerlaw_spectrum'
                print summary(like)

            d['hypothesis_0'] = source_dict(like, name, emin=emin, emax=emax,
                                            flux_units=self.flux_units,
                                            energy_units=self.energy_units,
                                            verbosity=self.verbosity)

            if self.cutoff_model is None:
                self.cutoff_model=PLSuperExpCutoff(norm=1e-9, index=1, cutoff=1000, e0=1000, b=1)
                self.cutoff_model.set_free('b', False)
                self.cutoff_model.set_flux(old_flux,emin=emin,emax=emax)
                self.cutoff_model.set_default_limits(oomp_limits=True)

            if self.verbosity: 
                print 'cutoff_model is',self.cutoff_model

            cutoff_spectrum=build_gtlike_spectrum(self.cutoff_model)
            like.setSpectrum(name,cutoff_spectrum)

            if self.verbosity: 
                print 'About to fit cutoff_model'
                print summary(like)

            paranoid_gtlike_fit(like, verbosity=self.verbosity)

            ll = like.logLike.value()

            if ll < d['hypothesis_0']['logLikelihood']:
                # if fit is worse than PowerLaw fit, then
                # restart fit with parameters almost
                # equal to best fit powerlaw
                cutoff_plaw=PLSuperExpCutoff(b=1)
                cutoff_plaw.set_free('b', False)
                cutoff_plaw.setp_gtlike('norm', d['hypothesis_0']['spectrum']['Prefactor'])
                cutoff_plaw.setp_gtlike('index', d['hypothesis_0']['spectrum']['Index'])
                cutoff_plaw.setp_gtlike('e0', d['hypothesis_0']['spectrum']['Scale'])
                cutoff_plaw.setp_gtlike('cutoff', 1e6)
                cutoff_plaw.set_default_limits(oomp_limits=True)

                temp=build_gtlike_spectrum(cutoff_plaw)
                like.setSpectrum(name,temp)

                if self.verbosity: 
                    print 'Redoing fit with cutoff same as plaw'
                    print summary(like)

                paranoid_gtlike_fit(like, verbosity=self.verbosity)

            if self.verbosity: 
                print 'Done fitting cutoff_spectrum'
                print summary(like)

            d['hypothesis_1'] = source_dict(like, name, emin=emin, emax=emax,
                                            flux_units=self.flux_units,
                                            energy_units=self.energy_units,
                                            verbosity=self.verbosity)

            if self.cutoff_xml_name is not None:
                like.writeXml(self.cutoff_xml_name)

            d['TS_cutoff']=d['hypothesis_1']['TS']['reoptimize']-d['hypothesis_0']['TS']['reoptimize']

            if self.verbosity: 
                print 'For cutoff test, TS_cutoff = ', d['TS_cutoff']
        except Exception, ex:
            print 'ERROR gtlike test cutoff: ', ex
            traceback.print_exc(file=sys.stdout)
            self.results = None
Пример #19
0
flux=args.flux
index=args.index
phibins=args.phibins

if args.position == 'galcenter':
    roi_dir = SkyDir(0,0,SkyDir.GALACTIC)
elif args.position == 'allsky':
    roi_dir=random_on_sphere()
elif args.position == 'bad':
    roi_dir=SkyDir(314.4346,-69.5670,SkyDir.GALACTIC)
elif args.position == 'pole':
    roi_dir=SkyDir(0,-90,SkyDir.GALACTIC)
elif args.position == 'w44':
    roi_dir=SkyDir(283.98999,1.355)

model_mc = PowerLaw(index=index)
model_mc.set_flux(flux, emin=args.emin, emax=args.emax)

if args.spatial == 'point':
    ps = PointSource(name=name, model=model_mc, skydir=roi_dir)
    point_sources, diffuse_sources = [ps],None
    sources = [ps]
elif args.spatial == 'disk':
    spatial_model = Disk(sigma=0.25, center=roi_dir)
    es = ExtendedSource(name=name, model=model_mc, spatial_model=spatial_model)
    point_sources, diffuse_sources = [],[es]
    sources = [es]
elif args.spatial == 'w44':
    spatial_model = EllipticalRing(major_axis=.3, minor_axis=0.19, pos_angle=-33, fraction=0.75, center=roi_dir)
    es = ExtendedSource(name=name, model=model_mc, spatial_model=spatial_model)
    point_sources, diffuse_sources = [],[es]
Пример #20
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    def _calculate(self):
        """ Compute the flux data points for each energy. """

        like         = self.like
        name         = self.name

        # Freeze all sources except one to make sed of.
        all_sources = like.sourceNames()

        if name not in all_sources:
            raise Exception("Cannot find source %s in list of sources" % name)

        saved_state = SuperState(like)

        self.results = dict(
            name=name,
            bands=[],
            min_ts=self.min_ts,
        )

        for i,(emin,emax,e_middle) in enumerate(zip(self.lower_energy,self.upper_energy,self.middle_energy)):
            if self.verbosity: print 'Calculating bandfits from %.0dMeV to %.0dMeV' % (emin,emax)


            like.setEnergyRange(float(emin)+1, float(emax)-1)

            # Scale the powerlaw to the input spectral model => helps with convergence
            old_flux = self.init_model.i_flux(emin=emin, emax=emax)
            model = PowerLaw(index=2, e0=e_middle)
            model.set_flux(old_flux, emin=emin, emax=emax)
            norm = model['norm']
            model.set_limits('norm',norm/float(self.fit_range),norm*self.fit_range, scale=norm)
            model.set_limits('index',-5,5)
            spectrum = build_gtlike_spectrum(model)

            like.setSpectrum(name,spectrum)
            like.syncSrcParams(name)

            if self.verbosity:
                print 'Before bandfits fitting from %.0dMeV to %.0dMeV' % (emin,emax)
                print summary(like)

            paranoid_gtlike_fit(like, verbosity=self.verbosity)

            if self.verbosity:
                print 'After bandfits fitting from %.0dMeV to %.0dMeV' % (emin,emax)
                print summary(like)

            r = source_dict(like, name, emin=emin, emax=emax,
                            flux_units=self.flux_units,
                            energy_units=self.energy_units,
                            verbosity=self.verbosity)

            if self.verbosity: print 'Calculating bandfits upper limit from %.0dMeV to %.0dMeV' % (emin,emax)
            g = GtlikePowerLawUpperLimit(like, name,
                                         powerlaw_index=self.upper_limit_index,
                                         cl=self.ul_confidence,
                                         emin=emin,emax=emax,
                                         flux_units=self.flux_units,
                                         energy_units=self.energy_units,
                                         upper_limit_kwargs=self.upper_limit_kwargs,
                                         include_prefactor=True,
                                         prefactor_energy=e_middle,
                                         verbosity=self.verbosity)
            r['upper_limit'] = g.todict()
            
            r['prefactor'] = powerlaw_prefactor_dict(like, name, errors=True, minos_errors=False,
                                                     flux_units=self.flux_units)

            r['significant']=r['TS']['reoptimize']>self.min_ts

            self.results['bands'].append(r)

        # revert to old model
        like.setEnergyRange(*self.init_energes)
        saved_state.restore()
Пример #21
0
    def _calculate(self):
        roi = self.roi
        name = self.name
        
        if self.verbosity: print 'Testing cutoff in pointlike'
        emin,emax=get_full_energy_range(roi)

        self.results = d = dict(
            energy = energy_dict(emin=emin, emax=emax, energy_units=self.energy_units)
        )

        saved_state = PointlikeState(roi)

        old_flux = roi.get_model(name).i_flux(emin,emax)

        if not isinstance(roi.get_model(name),PowerLaw):

            powerlaw_model=PowerLaw(norm=1e-11, index=2, e0=np.sqrt(emin*emax))
            powerlaw_model.set_mapper('Index', PowerLaw.default_limits['Index'])
            powerlaw_model.set_flux(old_flux,emin=emin,emax=emax)

            if self.verbosity: print "powerlaw_model is ",powerlaw_model

            roi.modify(which=name, model=powerlaw_model, keep_old_flux=False)

        fit = lambda: roi.fit(**self.fit_kwargs)
        def ts():
            old_quiet = roi.quiet; roi.quiet=True
            ts = roi.TS(name,quick=False)
            roi.quiet = old_quiet
            return ts

        spectrum = lambda: spectrum_to_dict(roi.get_model(name), errors=True)

        if self.verbosity: 
            print 'About to fit powerlaw_model'
            roi.print_summary()

        fit()
        
        if self.verbosity:
            print 'Done fitting powerlaw_model'
            roi.print_summary()

        d['hypothesis_0'] = source_dict(roi, name, emin=emin, emax=emax,
                                        flux_units=self.flux_units,
                                        energy_units=self.energy_units,
                                        verbosity=self.verbosity)

        if self.cutoff_model is not None:
            pass
        else:
            self.cutoff_model=PLSuperExpCutoff(norm=1e-9, index=1, cutoff=1000, e0=1000, b=1)
            # Note, don't limit the normalization parameter
            for p in ['Index', 'Cutoff', 'b']:
                self.cutoff_model.set_mapper(p, PLSuperExpCutoff.default_limits[p])
            self.cutoff_model.set_free('b', False)
            self.cutoff_model.set_flux(old_flux,emin=emin,emax=emax)

        if self.verbosity: print "cutoff_model is ",self.cutoff_model

        roi.modify(which=name, model=self.cutoff_model, keep_old_flux=False)

        if self.verbosity: 
            print 'About to fit cutoff_model'
            roi.print_summary()

        fit()

        ll = -roi.logLikelihood(roi.parameters())

        if ll < d['hypothesis_0']['logLikelihood']:
            # if fit is worse than PowerLaw fit, then
            # restart fit with parameters almost
            # equal to best fit powerlaw
            self.cutoff_plaw=PLSuperExpCutoff(b=1)
            self.cutoff_plaw.set_free('b', False)
            self.cutoff_plaw.setp('norm', d['hypothesis_0']['spectrum']['Norm'])
            self.cutoff_plaw.setp('index', d['hypothesis_0']['spectrum']['Index'])
            self.cutoff_plaw.setp('e0', d['hypothesis_0']['spectrum']['e0'])
            self.cutoff_plaw.setp('cutoff', 1e6)

            roi.modify(which=name, model=self.cutoff_plaw, keep_old_flux=False)
            fit()

            if self.verbosity: 
                print 'Redoing fit with cutoff same as plaw'
                print 'Before:'
                roi.print_summary()
                print fit()

        if self.verbosity:
            print 'Done fitting cutoff_model'
            roi.print_summary()

        d['hypothesis_1'] = source_dict(roi, name, emin=emin, emax=emax,
                                        flux_units=self.flux_units,
                                        energy_units=self.energy_units,
                                        verbosity=self.verbosity)


        d['TS_cutoff']=d['hypothesis_1']['TS']['noquick']-d['hypothesis_0']['TS']['noquick']

        saved_state.restore()
Пример #22
0
    def _calculate(self,*args,**kwargs):
        """ Convert all units into sympy arrays after the initial calculation. """

        like = self.like
        name = self.name

        init_energes = like.energies[[0,-1]]

        # Freeze all sources except one to make sed of.
        all_sources = like.sourceNames()

        if name not in all_sources:
            raise Exception("Cannot find source %s in list of sources" % name)

        # make copy of parameter values + free parameters
        
        saved_state = SuperState(like)

        if self.verbosity: print 'Freezing background sources'
        for other_name in get_background(like):
                if self.freeze_bg_diffuse:
                    if self.verbosity: print ' * Freezing diffuse source %s' % other_name
                    modify(like, other_name, free=False)
                else:
                    if self.verbosity: print ' * Freezing spectral shape for diffuse source %s' % other_name
                    modify(like, other_name, freeze_spectral_shape=True)
        for other_name in get_sources(like):
            if self.freeze_bg_sources:
                if self.verbosity: print ' * Freezing bg source %s' % other_name
                modify(like, other_name, free=False)
            else:
                if self.verbosity: print ' * Freezing spectral shape for bg source %s' % other_name
                modify(like, other_name, freeze_spectral_shape=True)

        self.raw_results = []
        for i,(lower,upper) in enumerate(zip(self.lower,self.upper)):

            like.setEnergyRange(float(lower)+1, float(upper)-1)

            e = np.sqrt(lower*upper)

            if self.verbosity: print 'Calculating SED from %.0dMeV to %.0dMeV' % (lower,upper)

            """ Note, the most robust method I have found for computing SEDs in gtlike is:
                    (a) Create a generic spectral model with a fixed spectral index.
                    (b) Set the 'Scale' to sqrt(emin*emax) so the prefactor is dNdE in the middle
                        of the sed bin.
                    (b) Set the limits to go from norm/fit_range to norm*fit_range and set the scale to 'norm'
            """ 
            old_flux = self.init_model.i_flux(emin=lower,emax=upper)
            model = PowerLaw(index=self.powerlaw_index, e0=e)
            model.set_flux(old_flux, emin=lower, emax=upper)
            norm = model['norm']
            model.set_limits('norm',norm/float(self.fit_range),norm*self.fit_range, scale=norm)
            model.set_limits('index',-5,5)
            model.freeze('index')
            spectrum = build_gtlike_spectrum(model)

            like.setSpectrum(name,spectrum)
            like.syncSrcParams(name)

            if self.verbosity:
                print 'Before fitting SED from %.0dMeV to %.0dMeV' % (lower,upper)
                print summary(like)

            paranoid_gtlike_fit(like, verbosity=self.verbosity)

            if self.verbosity:
                print 'After fitting SED from %.0dMeV to %.0dMeV' % (lower,upper)
                print summary(like)

            d = dict()
            self.raw_results.append(d)

            d['energy'] = energy_dict(emin=lower, emax=upper, energy_units=self.energy_units)
            d['flux'] = flux_dict(like, name, emin=lower,emax=upper, flux_units=self.flux_units, 
                                 errors=True, include_prefactor=True, prefactor_energy=e)
            d['prefactor'] = powerlaw_prefactor_dict(like, name, errors=self.save_hesse_errors, minos_errors=True,
                                                     flux_units=self.flux_units)
            d['TS'] = ts_dict(like, name, verbosity=self.verbosity)

            if self.verbosity: print 'Calculating SED upper limit from %.0dMeV to %.0dMeV' % (lower,upper)

            if self.always_upper_limit or d['TS']['reoptimize'] < self.min_ts:
                ul = GtlikePowerLawUpperLimit(like, name,
                                              cl=self.ul_confidence,
                                              emin=lower,emax=upper,
                                              flux_units=self.flux_units,
                                              energy_units=self.energy_units,
                                              upper_limit_kwargs=self.upper_limit_kwargs,
                                              include_prefactor=True,
                                              prefactor_energy=e,
                                              verbosity=self.verbosity,
                                             )
                d['upper_limit'] = ul.todict()

        # revert to old model
        like.setEnergyRange(*init_energes)
        saved_state.restore()

        self._condense_results()
Пример #23
0
def new_ps(
    roi,
    name,
    l,
    b,
    tsmap_kwargs=dict(size=10),
    fit_kwargs=dict(use_gradient=False),
    print_kwargs=dict(galactic=True, maxdist=15),
    localize=True,
    minuit_localizer=False,
):
    """ A 'throw away' convenience function to add a new source to
        the ROI, localize it, and then print out a string which can be
        used to modify an ROI to add a new source. """

    skydir = SkyDir(l, b, SkyDir.GALACTIC)

    roi.print_summary(**print_kwargs)

    emin, emax = roi.bin_edges[[0, -1]]

    model = PowerLaw(e0=np.sqrt(emin * emax))

    ps = PointSource(name=name, skydir=skydir, model=model)

    roi.add_source(ps)

    roi.print_summary(**print_kwargs)

    fit_prefactor(roi, name, **fit_kwargs)
    roi.fit(**fit_kwargs)

    roi.print_summary(**print_kwargs)

    if localize:
        if minuit_localizer:
            m = MinuitLocalizer(roi, which=name, fit_kwargs=fit_kwargs)
            m.localize()
        else:
            roi.localize(which=name, update=True)

    roi.fit(**fit_kwargs)

    roi.print_summary(**print_kwargs)

    print roi

    ts = roi.TS(which=name, quick=False, fit_kwargs=fit_kwargs)
    print 'TS for source %s is %.1f' % (name, ts)

    path = os.path.abspath(sys.argv[0])
    print """
Code to create point source:

    # Analysis came from %s
    ps=%s
    roi.add_source(ps)
""" % (path, pformat(ps))

    roi.save('roi.dat')

    roi.plot_tsmap(filename='residual_tsmap.pdf',
                   fitsfile='residual_tsmap.fits',
                   **tsmap_kwargs)
Пример #24
0
        Norm=14.56863965e-10*args.fluxfactor,
        Index_1=-1.504042874,
        Index_2=1.891184873,
        E_break=e_break,
        beta=0.1,
        e0=200)

    smooth_soft = SmoothBrokenPowerLaw(
        Index_1=+0.2,
        Index_2=1.891184873,
        E_break=e_break,
        beta=0.1,
        e0=200)
    smooth_soft.set_prefactor(smooth_hard(e_break),e_break)

    plaw=PowerLaw(index=1.891184873, e0=200)
    plaw.set_prefactor(smooth_hard(e_break), e_break)

    if spectrum == 'PowerLaw':
        W44.model = plaw
    elif spectrum == 'SmoothBrokenPowerLawHard':
        W44.model = smooth_hard
    elif spectrum == 'SmoothBrokenPowerLawSoft':
        W44.model = smooth_soft


elif source == 'IC443':
    """
    SmoothBrokenPowerlaw Spectrum is from:
        /u/gl/funk/data3/ExtendedSources/NewAnalysis/gtlike/IC443/SmoothBrokenPowerlaw/IC443_fitted_BINNED_freeMore_BSP_lowEnergy.minos.xml
Пример #25
0
class PowerLawApproximator(BaseFitter):

    defaults = BaseFitter.defaults + (
        ('npoints',1000,'number of points in fit'),
        ('e0',None,'scale for power law'),
        ('energy_units', 'MeV', 'default units to plot energy flux (y axis) in.'),
        ('flux_units',  'erg', 'default units to plot energy (x axis) in'),
)

    @keyword_options.decorate(defaults)
    def __init__(self, input_model, emin, emax, **kwargs):
        """ Create an approximate power law spectrum. """

        raise Exception("This code doesn't work yet. I think you need the exposure to do the fit correctly.")
        self.input_model = input_model
        self.emin = emin
        self.emax = emax

        keyword_options.process(self, kwargs)

        self._calculate()

    def _calculate(self):
        self.results = dict()

        energies = np.logspace(np.log10(self.emin),np.log10(self.emax),self.npoints)

        if self.e0 is None: 
            self.e0=np.sqrt(self.emin*self.emax)

        self.results['input_model'] = spectrum_to_dict(self.input_model)
        self.results['dnde'] = dnde = self.input_model(energies)

        self.pl_model = PowerLaw(e0=self.e0)
        self.pl_model.set_flux(self.input_model.i_flux(emin=self.emin,emax=self.emax),
                    emin=self.emin,emax=self.emax)

        def residuals(args):
            norm,index=args
            self.pl_model['norm']=norm
            self.pl_model['index']=index
            dnde_pl = self.pl_model(energies)
            #return np.sum((np.log(dnde) - np.log(dnde_pl))**2)
            print (np.log10(dnde)-np.log10(dnde_pl))**2
            return np.sum((np.log(dnde) - np.log(dnde_pl))**2)
            #return np.sum((dnde - dnde_pl)**2)

        best_norm,best_index=fmin(residuals,[self.pl_model['norm'],self.pl_model['index']])
        self.pl_model['norm']=best_norm
        self.pl_model['index']=best_index

        self.results['pl_model'] = spectrum_to_dict(self.pl_model)


    def plot(self,filename=None,axes=None,fignum=None,figsize=(4,4)):
        if axes is None:
            fig = P.figure(fignum,figsize)
            axes = SpectralAxes(fig=fig, 
                                rect=(0.22,0.15,0.75,0.8),
                                flux_units=self.flux_units,
                                energy_units=self.energy_units)
            fig.add_axes(axes)
            axes.set_xlim_units(self.emin*units.MeV, self.emax*units.MeV)

        sp=SpectrumPlotter(axes=axes)
        sp.plot(self.results['input_model'], label='input')
        sp.plot(self.results['pl_model'], label='powerlaw')
        
        if filename is not None:
            P.savefig(filename)

    if __name__ == "__main__":
        import doctest
        doctest.testmod()
Пример #26
0
class BandFitExtended(object):
    def __init__(self, which, energy_band, roi):
        """ extendedsource
            which             index of source
            energy_band       ROIEnergyBand object to fit.
            bands             all energy bands in roi. """

        self.energy_band = energy_band
        self.bands = self.energy_band.bands
        self.all_bands = roi.bands

        self.which = which

        self.all_mybands = roi.dsm.bgmodels[self.which].bands

        # list of the mybands corresponding to energy_bands
        self.mybands = []

        # Create a lsit of myband object corresponding to the bands
        # in the energy_band.
        for eb_band in self.bands:
            for band, myband in zip(self.all_bands, self.all_mybands):
                if eb_band == band:
                    self.mybands.append(myband)
                    break

    def bandLikelihoodExtended(self, parameters, band, myband):

        new_counts = parameters[0] * myband.er

        old_counts = band.bg_counts[self.which]

        tot_term = (band.bg_all_counts + band.ps_all_counts + myband.overlaps *
                    (new_counts - old_counts)) * band.phase_factor

        pix_term = (
            band.pix_counts *
            np.log(band.bg_all_pix_counts + band.ps_all_pix_counts +
                   myband.es_pix_counts *
                   (new_counts - old_counts))).sum() if band.has_pixels else 0.

        return tot_term - pix_term

    def energyBandLikelihoodExtended(self, parameters, m):
        m.set_parameters(parameters)
        return sum(
            self.bandLikelihoodExtended([b.expected(m)], b, mb)
            for b, mb in zip(self.bands, self.mybands))

    def normUncertaintyExtended(self):
        tot = 0
        for b, mb in zip(self.bands, self.mybands):
            if not b.has_pixels: continue
            my_pix_counts = mb.es_pix_counts * b.expected(self.m) * mb.er
            all_pix_counts = b.bg_all_pix_counts + b.ps_all_pix_counts - mb.es_pix_counts * b.bg_counts[
                self.which] + my_pix_counts
            tot += (b.pix_counts * (my_pix_counts / all_pix_counts)**2).sum()
        return tot**-0.5

    def fit(self, saveto=None):

        bad_fit = False
        self.m = PowerLaw(free=[True, False],
                          e0=(self.energy_band.emin *
                              self.energy_band.emax)**0.5)  # fix index to 2
        f = self.energyBandLikelihoodExtended

        self.fit = fmin(f,
                        self.m.get_parameters(),
                        disp=0,
                        full_output=1,
                        args=(self.m, ))

        def upper_limit():

            flux_copy = self.m[0]
            zp = self.energyBandLikelihoodExtended(np.asarray([-20]), self.m)

            # NB -- the 95% upper limit is calculated by assuming the likelihood is peaked at
            # 0 flux and finding the flux at which it has fallen by 1.35; this is a two-sided
            # 90% limit, or a one-sided 95% limit -- that's how it works, right?
            def f95(parameters):
                return abs(
                    self.energyBandLikelihoodExtended(parameters, self.m) -
                    zp - 1.35)

            # for some reason, can't get fsolve to work here.  good ol' fmin to the rescue
            self.energy_band.uflux = 10**fmin(f95,
                                              np.asarray([-11.75]),
                                              disp=0)[0]
            self.energy_band.lflux = None
            self.energy_band.flux = None

            self.m[0] = flux_copy

        # if flux below a certain level, set an upper limit
        if self.m[0] < 1e-20:
            bad_fit = True
            upper_limit()

        else:
            try:
                err = self.normUncertaintyExtended()
            except:
                bad_fit = True
                err = 0

            self.energy_band.flux = self.m[0]
            self.energy_band.uflux = self.energy_band.flux * (1 + err)
            self.energy_band.lflux = max(self.energy_band.flux * (1 - err),
                                         1e-30)

        if saveto is not None:
            for b, mb in zip(self.bands, self.mybands):
                b.__dict__[saveto] = (b.expected(self.m) *
                                      mb.er if not bad_fit else -1)

        if bad_fit:
            self.energy_band.ts = 0
        else:
            null_ll = sum(
                self.bandLikelihoodExtended([0], b, mb)
                for b, mb in zip(self.bands, self.mybands))
            alt_ll = sum(
                self.bandLikelihoodExtended([b.expected(self.m) *
                                             mb.er], b, mb)
                for b, mb in zip(self.bands, self.mybands))
            self.energy_band.ts = 2 * (null_ll - alt_ll)
Пример #27
0
class ExtendedSource(DiffuseSource):
    """ Class inherting from DiffuseSource but implementing a spatial source. 
        The main difference is the requirement of a spatial model to accomany 
        a spectral model. """

    defaults = (
        ('name', None, 'The name of the extended source.'),
        ('model', None, 'a Model object.'),
        ('spatial_model', None, """The spatial model to use. 
                                       This is a SpatialModel object."""),
    )

    @keyword_options.decorate(defaults)
    def __init__(self, **kwargs):
        """ Make the naming consistent with the PointSource object so that
            extended sources 'feel' like point sources.

            """
        keyword_options.process(self, kwargs)

        if self.model == None: self.model = PowerLaw()
        if self.spatial_model == None: self.spatial_model = Disk()

        if not isinstance(self.spatial_model, SpatialModel):
            raise Exception(
                "The diffuse_model passed to an Extended Source must inherit from SpatialModel."
            )

        super(ExtendedSource, self).__init__(diffuse_model=self.spatial_model,
                                             scaling_model=self.model,
                                             name=self.name)

        self.model.background = False

    @property
    def skydir(self):
        return self.spatial_model.center

    @property
    def smodel(self):
        """ No reason to keep a model & smodel. """
        return self.model

    @smodel.setter
    def smodel(self, value):
        self.model = value

    def __str__(self, indent=''):
        return indent + ('\n' + indent).join([
            '\n', '=' * 60,
            'Name:\t\t%s' % (self.name),
            'R.A. (J2000):\t\t%.5f' % (self.spatial_model.center.ra()),
            'Dec. (J2000):\t\t%.5f' % (self.spatial_model.center.dec()),
            'Model:\t\t%s' %
            (self.model.full_name()), '\t' + self.model.__str__(indent='\t'),
            'SpatialModel:\t%s' % (self.spatial_model.full_name()),
            '\t' + self.spatial_model.__str__(indent='\t')
        ])

    def copy(self):
        """ Create a deep copy of an extended source. """
        return ExtendedSource(name=self.name,
                              spatial_model=self.spatial_model.copy(),
                              model=self.model.copy())
Пример #28
0
    def fit(self, saveto=None):

        bad_fit = False
        self.m = PowerLaw(free=[True, False],
                          e0=(self.energy_band.emin *
                              self.energy_band.emax)**0.5)  # fix index to 2
        f = self.energyBandLikelihoodExtended

        self.fit = fmin(f,
                        self.m.get_parameters(),
                        disp=0,
                        full_output=1,
                        args=(self.m, ))

        def upper_limit():

            flux_copy = self.m[0]
            zp = self.energyBandLikelihoodExtended(np.asarray([-20]), self.m)

            # NB -- the 95% upper limit is calculated by assuming the likelihood is peaked at
            # 0 flux and finding the flux at which it has fallen by 1.35; this is a two-sided
            # 90% limit, or a one-sided 95% limit -- that's how it works, right?
            def f95(parameters):
                return abs(
                    self.energyBandLikelihoodExtended(parameters, self.m) -
                    zp - 1.35)

            # for some reason, can't get fsolve to work here.  good ol' fmin to the rescue
            self.energy_band.uflux = 10**fmin(f95,
                                              np.asarray([-11.75]),
                                              disp=0)[0]
            self.energy_band.lflux = None
            self.energy_band.flux = None

            self.m[0] = flux_copy

        # if flux below a certain level, set an upper limit
        if self.m[0] < 1e-20:
            bad_fit = True
            upper_limit()

        else:
            try:
                err = self.normUncertaintyExtended()
            except:
                bad_fit = True
                err = 0

            self.energy_band.flux = self.m[0]
            self.energy_band.uflux = self.energy_band.flux * (1 + err)
            self.energy_band.lflux = max(self.energy_band.flux * (1 - err),
                                         1e-30)

        if saveto is not None:
            for b, mb in zip(self.bands, self.mybands):
                b.__dict__[saveto] = (b.expected(self.m) *
                                      mb.er if not bad_fit else -1)

        if bad_fit:
            self.energy_band.ts = 0
        else:
            null_ll = sum(
                self.bandLikelihoodExtended([0], b, mb)
                for b, mb in zip(self.bands, self.mybands))
            alt_ll = sum(
                self.bandLikelihoodExtended([b.expected(self.m) *
                                             mb.er], b, mb)
                for b, mb in zip(self.bands, self.mybands))
            self.energy_band.ts = 2 * (null_ll - alt_ll)
Пример #29
0
def get_diffuse_source(spatialModel='ConstantValue',
                              spatialModelFile=None,
                              spectralModel='PowerLaw',
                              spectralModelFile=None,
                              name=None,
                              diffdir = None):

    """ Return a DiffuseSource instance suitable for
         instantiating a child of ROIDiffuseModel.

         NB -- don't support front/back distinction atm.

         The list of supported models is currently very short, but covers
         the usual cases for modeling diffuse backgrounds.  Additional
         use cases can be developed on an ad hoc basis.
         
         Arguments:
         
         spatialModel -- an XML-style keyword.  Valid options are
                               1) ConstantValue (isotropic)
                               2) MapCubeFunction (from a FITS file)
                               
         spatialModelFile -- if a mapcube is specified, its location
         
         spectralModel -- This can be either an XML-style keyword or an
                                instance of Model.
                                If an XML-style keyword, valid options are
                                1) FileFunction
                                2) PowerLaw
                                3) Constant
                               
         spectralModelFile -- if a tabular function is specified,
                                     its location

         name -- a name for the ol' model

         
         diffdir -- if the XML files specify paths relative to some
                        directory, set this variable appropriately
    """

    if (diffdir is not None):
        if spatialModelFile is not None:
            spatialModelFile = os.path.join(diffdir,spatialModelFile)
        if spectralModelFile is not None:
            spectralModelFile = os.path.join(diffdir,spectralModelFile)

    # check input sanity
    if not isinstance(spectralModel,Model):
        if (spectralModelFile is not None):
            if not os.path.exists(path.expand(spectralModelFile)):
                raise Exception('Could not find the ASCII file specified for FileFunction')
        elif not (spectralModel == 'PowerLaw' or spectralModel == 'Constant'):
            raise NotImplementedError,'Must provide one of the understood spectral models.'
        else:
            pass

    if spatialModel=='MapCubeFunction':
        if (spatialModelFile is None) or (not os.path.exists(path.expand(spatialModelFile))):
            raise Exception('Could not find the FITS file specified for MapCubeFunction (file = %s).' % spatialModelFile)
    elif spatialModel != 'ConstantValue':
        raise NotImplementedError,'Must provide one of the understood spatial models.'
    else:
        pass                  

    ston = Singleton2()
    dmodel = None; smodel = None


    # deal with isotropic models
    if spatialModel=='ConstantValue':
        if isinstance(spectralModel,Model):
            smodel=spectralModel
            dmodel=IsotropicConstant()
        elif spectralModelFile is not None:
            smodel = FileFunction(normalization=1, file=spectralModelFile)
            dmodel = IsotropicConstant()
        elif spectralModel == 'PowerLaw':
            # use Sreekumar-like defaults
            smodel = PowerLaw(index=2.1)
            smodel.set_flux(1.5e-5, emin=100, emax=N.inf)

            dmodel = IsotropicConstant()
        else:
            raise Exception("Unable to parse input.")

    # deal with mapcubes
    else:
        if spectralModel == 'FileFunction':
            dmodel1 = IsotropicSpectrum(spectralModelFile)
            dmodel2 = ston.add(DiffuseFunction,spatialModelFile,spatialModelFile)
            dmodel  = CompositeSkySpectrum(dmodel1,dmodel2)
            dmodel.saveme1 = dmodel1; dmodel.saveme2 = dmodel2
            smodel  = Constant()
        else:
            dmodel = ston.add(DiffuseFunction,path.expand(spatialModelFile),path.expand(spatialModelFile))
            dmodel.filename=spatialModelFile
            if spectralModel == 'PowerLaw':
                smodel = ScalingPowerLaw()
            elif spectralModel == 'Constant':
                smodel = Constant()
            else:
                smodel = spectralModel

    if (dmodel is None) or (smodel is None):
         raise Exception('Was unable to parse input.')

    return DiffuseSource(dmodel,smodel,name)
Пример #30
0
    def _calculate(self, *args, **kwargs):
        """ Convert all units into sympy arrays after the initial calculation. """

        like = self.like
        name = self.name

        init_energes = like.energies[[0, -1]]

        # Freeze all sources except one to make sed of.
        all_sources = like.sourceNames()

        if name not in all_sources:
            raise Exception("Cannot find source %s in list of sources" % name)

        # make copy of parameter values + free parameters

        saved_state = SuperState(like)

        if self.verbosity: print 'Freezing background sources'
        for other_name in get_background(like):
            if self.freeze_bg_diffuse:
                if self.verbosity:
                    print ' * Freezing diffuse source %s' % other_name
                modify(like, other_name, free=False)
            else:
                if self.verbosity:
                    print ' * Freezing spectral shape for diffuse source %s' % other_name
                modify(like, other_name, freeze_spectral_shape=True)
        for other_name in get_sources(like):
            if self.freeze_bg_sources:
                if self.verbosity:
                    print ' * Freezing bg source %s' % other_name
                modify(like, other_name, free=False)
            else:
                if self.verbosity:
                    print ' * Freezing spectral shape for bg source %s' % other_name
                modify(like, other_name, freeze_spectral_shape=True)

        self.raw_results = []
        for i, (lower, upper) in enumerate(zip(self.lower, self.upper)):

            like.setEnergyRange(float(lower) + 1, float(upper) - 1)

            e = np.sqrt(lower * upper)

            if self.verbosity:
                print 'Calculating SED from %.0dMeV to %.0dMeV' % (lower,
                                                                   upper)
            """ Note, the most robust method I have found for computing SEDs in gtlike is:
                    (a) Create a generic spectral model with a fixed spectral index.
                    (b) Set the 'Scale' to sqrt(emin*emax) so the prefactor is dNdE in the middle
                        of the sed bin.
                    (b) Set the limits to go from norm/fit_range to norm*fit_range and set the scale to 'norm'
            """
            old_flux = self.init_model.i_flux(emin=lower, emax=upper)
            model = PowerLaw(index=self.powerlaw_index, e0=e)
            model.set_flux(old_flux, emin=lower, emax=upper)
            norm = model['norm']
            model.set_limits('norm',
                             norm / float(self.fit_range),
                             norm * self.fit_range,
                             scale=norm)
            model.set_limits('index', -5, 5)
            model.freeze('index')
            spectrum = build_gtlike_spectrum(model)

            like.setSpectrum(name, spectrum)
            like.syncSrcParams(name)

            if self.verbosity:
                print 'Before fitting SED from %.0dMeV to %.0dMeV' % (lower,
                                                                      upper)
                print summary(like)

            paranoid_gtlike_fit(like, verbosity=self.verbosity)

            if self.verbosity:
                print 'After fitting SED from %.0dMeV to %.0dMeV' % (lower,
                                                                     upper)
                print summary(like)

            d = dict()
            self.raw_results.append(d)

            d['energy'] = energy_dict(emin=lower,
                                      emax=upper,
                                      energy_units=self.energy_units)
            d['flux'] = flux_dict(like,
                                  name,
                                  emin=lower,
                                  emax=upper,
                                  flux_units=self.flux_units,
                                  errors=True,
                                  include_prefactor=True,
                                  prefactor_energy=e)
            d['prefactor'] = powerlaw_prefactor_dict(
                like,
                name,
                errors=self.save_hesse_errors,
                minos_errors=True,
                flux_units=self.flux_units)
            d['TS'] = ts_dict(like, name, verbosity=self.verbosity)

            if self.verbosity:
                print 'Calculating SED upper limit from %.0dMeV to %.0dMeV' % (
                    lower, upper)

            if self.always_upper_limit or d['TS']['reoptimize'] < self.min_ts:
                ul = GtlikePowerLawUpperLimit(
                    like,
                    name,
                    cl=self.ul_confidence,
                    emin=lower,
                    emax=upper,
                    flux_units=self.flux_units,
                    energy_units=self.energy_units,
                    upper_limit_kwargs=self.upper_limit_kwargs,
                    include_prefactor=True,
                    prefactor_energy=e,
                    verbosity=self.verbosity,
                )
                d['upper_limit'] = ul.todict()

        # revert to old model
        like.setEnergyRange(*init_energes)
        saved_state.restore()

        self._condense_results()
Пример #31
0
    def test_extended_source(self):

        PointlikeTest.p('USE_GRADIENT=%s' % PointlikeTest.USE_GRADIENT)

        if PointlikeTest.VERBOSE:
            PointlikeTest.p(
                'Analyze a simulated extended source against an isotropic background (E>10GeV)'
            )

        center = SkyDir(0, 0)

        # Sreekumar-like isotropic
        point_sources = []
        diffuse_sources = [
            get_diffuse_source('ConstantValue', None, 'PowerLaw', None,
                               'Isotropic Diffuse')
        ]

        model = PowerLaw(index=2)
        model.set_flux(1e-4)

        if PointlikeTest.VERBOSE:
            PointlikeTest.p('Simulating gaussian source with sigma=1 degrees')
        spatial_model = Gaussian(p=[1], center=center)

        es_mc = ExtendedSource(name='source',
                               spatial_model=spatial_model,
                               model=model)
        es_fit = es_mc.copy()
        diffuse_sources.append(es_fit)

        roi = PointlikeTest.get_roi('extended_test',
                                    center,
                                    point_sources,
                                    diffuse_sources,
                                    emin=1e4)
        global roi_ext
        roi_ext = roi  # helps with debugging

        if PointlikeTest.VERBOSE:
            print roi

        if PointlikeTest.VERBOSE:
            PointlikeTest.p('Setting initial spatial model to 0.3 degrees')
        roi.modify(which='source', spatial_model=Gaussian(0.3))

        if PointlikeTest.VERBOSE: print roi
        roi.fit(use_gradient=PointlikeTest.USE_GRADIENT)
        if PointlikeTest.VERBOSE: print roi
        roi.fit_extension(which='source',
                          use_gradient=PointlikeTest.USE_GRADIENT)
        roi.localize(update=True)
        roi.fit(use_gradient=PointlikeTest.USE_GRADIENT)

        self.compare_model(es_fit, es_mc)
        self.compare_spatial_model(es_fit, es_mc, roi.lsigma)

        self.assertTrue(
            roi.TS(which='source') > 25, 'The source should be significant')
        self.assertTrue(
            roi.TS_ext(which='source') > 25, 'And significantly extended')

        es_mc.spatial_model.save_template('$SIMDIR/extended_template.fits')

        if PointlikeTest.VERBOSE:
            PointlikeTest.p(
                'Now, switching from Disk soruce to template source.')

        roi.del_source(which='source')
        template_source = ExtendedSource(
            name='template_source',
            model=es_mc.model,
            spatial_model=SpatialMap(file='$SIMDIR/extended_template.fits'))

        roi.add_source(template_source)

        roi.fit(use_gradient=PointlikeTest.USE_GRADIENT)

        self.compare_model(template_source, es_mc)

        self.assertTrue(
            roi.TS(which='template_source') > 25,
            'Make sure these functions work similary with spatial_map')
Пример #32
0
    def build_roi(self, name, fast):


        if fast:
            roi_size=5
            binsperdec = 2
            max_free=2
            free_radius=2
        else:
            roi_size = 10
            binsperdec = 4
            max_free=5
            free_radius=5

        catalog = Catalog2FGL('$FERMI/catalogs/gll_psc_v05.fit', 
                              latextdir='$FERMI/extended_archives/gll_psc_v05_templates',
                              prune_radius=0,
                              max_free=max_free,
                              free_radius=free_radius,
                              limit_parameters=True)

        ft1 = self.radiopsr_loader.get_ft1(name)
        ft2 = self.radiopsr_loader.get_ft2(name)
        ltcube = self.radiopsr_loader.get_ltcube(name)
        binfile = self.radiopsr_loader.get_binfile(name, binsperdec)

        roi_dir = self.radiopsr_loader.get_skydir(name)

        ds = DataSpecification(
            ft1files = ft1,
            ft2files = ft2,
            ltcube   = ltcube,
            binfile  = binfile)

        sa = SpectralAnalysis(ds,
                              binsperdec = binsperdec,
                              emin       = 100,
                              emax       = 1000000,
                              irf        = "P7SOURCE_V6",
                              roi_dir    = roi_dir,
                              maxROI     = roi_size,
                              minROI     = roi_size,
                              event_class= 0)

        fit_emin = 1e2
        fit_emax = 10**5.5

        model=PowerLaw(index=2, e0=np.sqrt(fit_emin*fit_emax))
        model.set_limits('index',-5,5)

        ps = PointSource(name=name, model=model, skydir=roi_dir)
        point_sources = [ps]

        diffuse_sources = get_default_diffuse(diffdir="/afs/slac/g/glast/groups/diffuse/rings/2year",
                                   gfile="ring_2year_P76_v0.fits",
                                   ifile="isotrop_2year_P76_source_v0.txt",
                                   limit_parameters=True)

        roi=sa.roi(point_sources=point_sources,
                   diffuse_sources=diffuse_sources,
                   catalogs=catalog,
                   fit_emin=fit_emin, fit_emax=fit_emax)
        return roi
Пример #33
0
    def _calculate(self):
        like = self.like
        name = self.name

        if self.verbosity: print 'Testing cutoff in gtlike'

        saved_state = SuperState(like)

        emin, emax = get_full_energy_range(like)

        self.results = d = dict(energy=energy_dict(
            emin=emin, emax=emax, energy_units=self.energy_units))

        try:

            def get_flux():
                return like.flux(name, emin, emax)

            def spectrum():
                source = like.logLike.getSource(name)
                s = source.spectrum()
                return spectrum_to_dict(s, errors=True)

            old_flux = get_flux()

            if spectrum()['name'] == 'PowerLaw':
                pass
            else:
                powerlaw_model = PowerLaw(norm=1e-11,
                                          index=2,
                                          e0=np.sqrt(emin * emax))
                powerlaw_model.set_flux(old_flux, emin=emin, emax=emax)
                powerlaw_model.set_default_limits(oomp_limits=True)

                if self.verbosity: print 'powerlaw_model is', powerlaw_model

                powerlaw_spectrum = build_gtlike_spectrum(powerlaw_model)
                like.setSpectrum(name, powerlaw_spectrum)

            if self.verbosity:
                print 'About to fit powerlaw_spectrum'
                print summary(like)

            paranoid_gtlike_fit(like, verbosity=self.verbosity)

            if self.verbosity:
                print 'Done fitting powerlaw_spectrum'
                print summary(like)

            d['hypothesis_0'] = source_dict(like,
                                            name,
                                            emin=emin,
                                            emax=emax,
                                            flux_units=self.flux_units,
                                            energy_units=self.energy_units,
                                            verbosity=self.verbosity)

            if self.cutoff_model is None:
                self.cutoff_model = PLSuperExpCutoff(norm=1e-9,
                                                     index=1,
                                                     cutoff=1000,
                                                     e0=1000,
                                                     b=1)
                self.cutoff_model.set_free('b', False)
                self.cutoff_model.set_flux(old_flux, emin=emin, emax=emax)
                self.cutoff_model.set_default_limits(oomp_limits=True)

            if self.verbosity:
                print 'cutoff_model is', self.cutoff_model

            cutoff_spectrum = build_gtlike_spectrum(self.cutoff_model)
            like.setSpectrum(name, cutoff_spectrum)

            if self.verbosity:
                print 'About to fit cutoff_model'
                print summary(like)

            paranoid_gtlike_fit(like, verbosity=self.verbosity)

            ll = like.logLike.value()

            if ll < d['hypothesis_0']['logLikelihood']:
                # if fit is worse than PowerLaw fit, then
                # restart fit with parameters almost
                # equal to best fit powerlaw
                cutoff_plaw = PLSuperExpCutoff(b=1)
                cutoff_plaw.set_free('b', False)
                cutoff_plaw.setp_gtlike(
                    'norm', d['hypothesis_0']['spectrum']['Prefactor'])
                cutoff_plaw.setp_gtlike('index',
                                        d['hypothesis_0']['spectrum']['Index'])
                cutoff_plaw.setp_gtlike('e0',
                                        d['hypothesis_0']['spectrum']['Scale'])
                cutoff_plaw.setp_gtlike('cutoff', 1e6)
                cutoff_plaw.set_default_limits(oomp_limits=True)

                temp = build_gtlike_spectrum(cutoff_plaw)
                like.setSpectrum(name, temp)

                if self.verbosity:
                    print 'Redoing fit with cutoff same as plaw'
                    print summary(like)

                paranoid_gtlike_fit(like, verbosity=self.verbosity)

            if self.verbosity:
                print 'Done fitting cutoff_spectrum'
                print summary(like)

            d['hypothesis_1'] = source_dict(like,
                                            name,
                                            emin=emin,
                                            emax=emax,
                                            flux_units=self.flux_units,
                                            energy_units=self.energy_units,
                                            verbosity=self.verbosity)

            if self.cutoff_xml_name is not None:
                like.writeXml(self.cutoff_xml_name)

            d['TS_cutoff'] = d['hypothesis_1']['TS']['reoptimize'] - d[
                'hypothesis_0']['TS']['reoptimize']

            if self.verbosity:
                print 'For cutoff test, TS_cutoff = ', d['TS_cutoff']
        except Exception, ex:
            print 'ERROR gtlike test cutoff: ', ex
            traceback.print_exc(file=sys.stdout)
            self.results = None
Пример #34
0
    def integral(skydir):
        i = lambda m: m.integral(skydir, emin, emax)
        return i(gal.dmodel[0]) + i(iso.dmodel[0])

    bg_ratio = integral(SkyDir(0,0,SkyDir.GALACTIC))/integral(roi_dir)
    flux = galcenter_flux*bg_ratio**-0.5

    print 'index=%.1f, galcenter_flux=%.1e, bg_ratio=%.2f, l,b=%.2f,%.2f, flux=%.1e' % \
            (index,galcenter_flux,bg_ratio,roi_dir.l(),roi_dir.b(),flux)

    name = 'source_index_%g' % index

    tempdir = mkdtemp(prefix='/scratch/')

    model_mc = PowerLaw(index=index); model_mc.set_flux(flux, 1e2, 1e5)

    ft1 = join(tempdir,'ft1.fits')
    binfile = join(tempdir,'binned.fits')
    ft2 = join(tempdir, 'ft2.fits')
    ltcube = join(tempdir, 'ltcube.fits')
    ds = DataSpecification(
        ft1files = ft1,
        ft2files = ft2,
        binfile = binfile,
        ltcube = ltcube)

    sa = SpectralAnalysisMC(ds,
                            emin=emin,
                            emax=emax,
                            binsperdec=8,
Пример #35
0
irf="P7SOURCE_V6"

skydir_mc = SkyDir()

bg = get_sreekumar()

ft2 = dict2fgl['ft2']
ltcube = dict2fgl['ltcube']

results = []

for extension_mc in extensions:

    print 'Looping over extension_mc=%g' % extension_mc

    model_mc = PowerLaw(index=index_mc)
    model_mc.set_flux(flux_mc(extension_mc), emin, emax)

    r = dict(
        type = args.type,
        mc = dict(
            extension=extension_mc,
            gal=[ skydir_mc.l(), skydir_mc.b() ],
            cel=[ skydir_mc.ra(), skydir_mc.dec() ],
            model=spectrum_to_dict(model_mc),
            flux=pointlike_model_to_flux(model_mc, emin, emax),
        )
    )

    tempdir = mkdtemp()
Пример #36
0
PixelData(ft1files=diffuse_ft1, binfile=diffuse_binfile, binsperdec=4, event_class=0)

results_dict = []

index_mc = 2

for flux_mc in [1e-9, 3e-6, 3e-9, 1e-6, 1e-8, 3e-7, 3e-8, 1e-7]:

    source_str = "%g_%g_%s" % (flux_mc, index_mc, istr)

    print "Flux_mc=%g, Index_mc=%g" % (flux_mc, index_mc)

    name_mc = "source_%s" % istr

    model_mc = PowerLaw(p=[1, index_mc])
    model_mc.set_flux(flux_mc, 100, N.inf)

    source_mc = PointSource(name=name_mc, skydir=skydir_mc, model=model_mc)

    source_ft1 = join(tempdir, "source_%s_ft1.fits" % source_str)
    source_binfile = join(tempdir, "source_%s_binned.fits" % source_str)

    all_binfile = join(tempdir, "all_%s_binned.fits" % source_str)

    mc = MonteCarlo(
        point_sources=source_mc,
        seed=i,
        irf=irf,
        ft1=source_ft1,
        ft2=ft2,
Пример #37
0
    def _calculate(self):
        roi = self.roi
        name = self.name

        if self.verbosity: print 'Testing cutoff in pointlike'
        emin, emax = get_full_energy_range(roi)

        self.results = d = dict(energy=energy_dict(
            emin=emin, emax=emax, energy_units=self.energy_units))

        saved_state = PointlikeState(roi)

        old_flux = roi.get_model(name).i_flux(emin, emax)

        if not isinstance(roi.get_model(name), PowerLaw):

            powerlaw_model = PowerLaw(norm=1e-11,
                                      index=2,
                                      e0=np.sqrt(emin * emax))
            powerlaw_model.set_mapper('Index',
                                      PowerLaw.default_limits['Index'])
            powerlaw_model.set_flux(old_flux, emin=emin, emax=emax)

            if self.verbosity: print "powerlaw_model is ", powerlaw_model

            roi.modify(which=name, model=powerlaw_model, keep_old_flux=False)

        fit = lambda: roi.fit(**self.fit_kwargs)

        def ts():
            old_quiet = roi.quiet
            roi.quiet = True
            ts = roi.TS(name, quick=False)
            roi.quiet = old_quiet
            return ts

        spectrum = lambda: spectrum_to_dict(roi.get_model(name), errors=True)

        if self.verbosity:
            print 'About to fit powerlaw_model'
            roi.print_summary()

        fit()

        if self.verbosity:
            print 'Done fitting powerlaw_model'
            roi.print_summary()

        d['hypothesis_0'] = source_dict(roi,
                                        name,
                                        emin=emin,
                                        emax=emax,
                                        flux_units=self.flux_units,
                                        energy_units=self.energy_units,
                                        verbosity=self.verbosity)

        if self.cutoff_model is not None:
            pass
        else:
            self.cutoff_model = PLSuperExpCutoff(norm=1e-9,
                                                 index=1,
                                                 cutoff=1000,
                                                 e0=1000,
                                                 b=1)
            # Note, don't limit the normalization parameter
            for p in ['Index', 'Cutoff', 'b']:
                self.cutoff_model.set_mapper(
                    p, PLSuperExpCutoff.default_limits[p])
            self.cutoff_model.set_free('b', False)
            self.cutoff_model.set_flux(old_flux, emin=emin, emax=emax)

        if self.verbosity: print "cutoff_model is ", self.cutoff_model

        roi.modify(which=name, model=self.cutoff_model, keep_old_flux=False)

        if self.verbosity:
            print 'About to fit cutoff_model'
            roi.print_summary()

        fit()

        ll = -roi.logLikelihood(roi.parameters())

        if ll < d['hypothesis_0']['logLikelihood']:
            # if fit is worse than PowerLaw fit, then
            # restart fit with parameters almost
            # equal to best fit powerlaw
            self.cutoff_plaw = PLSuperExpCutoff(b=1)
            self.cutoff_plaw.set_free('b', False)
            self.cutoff_plaw.setp('norm',
                                  d['hypothesis_0']['spectrum']['Norm'])
            self.cutoff_plaw.setp('index',
                                  d['hypothesis_0']['spectrum']['Index'])
            self.cutoff_plaw.setp('e0', d['hypothesis_0']['spectrum']['e0'])
            self.cutoff_plaw.setp('cutoff', 1e6)

            roi.modify(which=name, model=self.cutoff_plaw, keep_old_flux=False)
            fit()

            if self.verbosity:
                print 'Redoing fit with cutoff same as plaw'
                print 'Before:'
                roi.print_summary()
                print fit()

        if self.verbosity:
            print 'Done fitting cutoff_model'
            roi.print_summary()

        d['hypothesis_1'] = source_dict(roi,
                                        name,
                                        emin=emin,
                                        emax=emax,
                                        flux_units=self.flux_units,
                                        energy_units=self.energy_units,
                                        verbosity=self.verbosity)

        d['TS_cutoff'] = d['hypothesis_1']['TS']['noquick'] - d[
            'hypothesis_0']['TS']['noquick']

        saved_state.restore()
Пример #38
0
    def _compute(self):
        """ Wrap up calculating the flux upper limit for a powerlaw
            source.  This function employes the pyLikelihood function
            IntegralUpperLimit to calculate a Bayesian upper limit.

            The primary benefit of this function is that it replaces the
            spectral model automatically with a PowerLaw spectral model
            and fixes the index to -2. It then picks a better scale for the
            powerlaw and gives the upper limit calculation a more reasonable
            starting value, which helps the convergence.
        """
        if self.verbosity: print 'Calculating gtlike power-law upper limit'
        like = self.like
        name = self.name

        saved_state = SuperState(like)

        e = np.sqrt(self.emin*self.emax)

        """ I had tons of trouble getting a robust fitting algorithm. 
            The problem with computing upper limits is
                (a) Getting an initial fit of the region (with the spectral index
                    fixed) to converge
                (b) Getting the upper limit to integrate over a good range.

            This is what I found to be most robust way to compute upper limits:
                (a) Create a generic powerlaw model with the spectral index fixed
                    at the desired value (typically set to -2).
                    Note, don't set e0, use default. This ensures that the
                    prefactor range really does convert to a physically reasonable
                    range of parameters.
                (b) Give the spectral model the pointlike default spectral limits.
                    This is important because it gives the source a big enough range 
                    such that the upper limit can find a proper integration range.
                (c) Set the flux of the current model to equal the flux of the input model.
                    This starts the fitter at a reasonable value. Do this setting with 
                    the set_flux flag strict=False beacuse, in case the initial fit totally
                    failed to converge (flux -> 0), you don't want to put the starting
                    value fo the flux too far away from the true value.
                (d) Keep the lower and upper limit on the prefactor as the pointlike default limits,
                    but set the scale of the source to be the new 'norm' found by preserving
                    the flux. This ensures the fitter doesn't have too much trouble finding
                    the true minimum.
            
            Using this procedure, you get a reasonable parameter limits which allows the
            preliminary fit to converge and the upper limits code to integrate over a reasonable
            parameter range.
        """
        source = like.logLike.getSource(name)
        spectrum=source.spectrum()

        old_flux = like.flux(name, self.emin, self.emax)
        model = PowerLaw(index=self.powerlaw_index)
        model.set_flux(old_flux, emin=self.emin, emax=self.emax, strict=False)
        model.set_default_limits(oomp_limits=True)

        spectrum = build_gtlike_spectrum(model)
        like.setSpectrum(name,spectrum)
        like.syncSrcParams(name)

        results = super(GtlikePowerLawUpperLimit,self)._compute()

        saved_state.restore()