def test_sersic_vs_hernquist_kinematics(self):
"""
attention: this test only works for Sersic indices > \approx 2!
Lower n_sersic will result in different predictions with the Hernquist assumptions
replacing the correct Light model!
:return:
"""
# anisotropy profile
anisotropy_type = 'OsipkovMerritt'
r_ani = 2.
kwargs_anisotropy = {'r_ani': r_ani} # anisotropy radius [arcsec]
# aperture as slit
aperture_type = 'slit'
length = 3.8
width = 0.9
kwargs_aperture = {'length': length, 'width': width, 'center_ra': 0, 'center_dec': 0, 'angle': 0}
psf_fwhm = 0.7 # Gaussian FWHM psf
kwargs_cosmo = {'D_d': 1000, 'D_s': 1500, 'D_ds': 800}
# light profile
light_profile_list = ['SERSIC']
r_sersic = .3
n_sersic = 2.8
kwargs_light = [{'amp': 1., 'R_sersic': r_sersic, 'n_sersic': n_sersic}] # effective half light radius (2d projected) in arcsec
# mass profile
mass_profile_list = ['SPP']
theta_E = 1.2
gamma = 2.
kwargs_profile = [{'theta_E': theta_E, 'gamma': gamma}] # Einstein radius (arcsec) and power-law slope
# Hernquist fit to Sersic profile
lens_analysis = LensAnalysis({'lens_light_model_list': ['SERSIC'], 'lens_model_list': []})
r_eff = lens_analysis.half_light_radius_lens(kwargs_light, deltaPix=0.1, numPix=100)
print(r_eff)
light_profile_list_hernquist = ['HERNQUIST']
kwargs_light_hernquist = [{'Rs': r_eff*0.551, 'amp': 1.}]
# mge of light profile
lightModel = LightModel(light_profile_list)
r_array = np.logspace(-3, 2, 100) * r_eff * 2
print(r_sersic/r_eff, 'r_sersic/r_eff')
flux_r = lightModel.surface_brightness(r_array, 0, kwargs_light)
amps, sigmas, norm = mge.mge_1d(r_array, flux_r, N=20)
light_profile_list_mge = ['MULTI_GAUSSIAN']
kwargs_light_mge = [{'amp': amps, 'sigma': sigmas}]
print(amps, sigmas, 'amp', 'sigma')
galkin = Galkin(mass_profile_list, light_profile_list_hernquist, aperture_type=aperture_type, anisotropy_model=anisotropy_type, fwhm=psf_fwhm, kwargs_cosmo=kwargs_cosmo)
sigma_v = galkin.vel_disp(kwargs_profile, kwargs_light_hernquist, kwargs_anisotropy, kwargs_aperture)
galkin = Galkin(mass_profile_list, light_profile_list_mge, aperture_type=aperture_type, anisotropy_model=anisotropy_type, fwhm=psf_fwhm, kwargs_cosmo=kwargs_cosmo)
sigma_v2 = galkin.vel_disp(kwargs_profile, kwargs_light_mge, kwargs_anisotropy, kwargs_aperture)
print(sigma_v, sigma_v2, 'sigma_v Galkin, sigma_v MGEn')
print((sigma_v/sigma_v2)**2)
npt.assert_almost_equal((sigma_v-sigma_v2)/sigma_v2, 0, decimal=1)
def test_mge_light_and_mass(self):
# anisotropy profile
anisotropy_type = 'OsipkovMerritt'
r_ani = 2.
kwargs_anisotropy = {'r_ani': r_ani} # anisotropy radius [arcsec]
# aperture as slit
aperture_type = 'slit'
length = 3.8
width = 0.9
kwargs_aperture = {'length': length, 'width': width, 'center_ra': 0, 'center_dec': 0, 'angle': 0}
psf_fwhm = 0.7 # Gaussian FWHM psf
kwargs_cosmo = {'D_d': 1000, 'D_s': 1500, 'D_ds': 800}
# light profile
light_profile_list = ['HERNQUIST']
r_eff = 1.8
kwargs_light = [{'Rs': r_eff, 'amp': 1.}] # effective half light radius (2d projected) in arcsec
# mass profile
mass_profile_list = ['SPP']
theta_E = 1.2
gamma = 2.
kwargs_profile = [{'theta_E': theta_E, 'gamma': gamma}] # Einstein radius (arcsec) and power-law slope
# mge of light profile
lightModel = LightModel(light_profile_list)
r_array = np.logspace(-2, 2, 200) * r_eff * 2
flux_r = lightModel.surface_brightness(r_array, 0, kwargs_light)
amps, sigmas, norm = mge.mge_1d(r_array, flux_r, N=20)
light_profile_list_mge = ['MULTI_GAUSSIAN']
kwargs_light_mge = [{'amp': amps, 'sigma': sigmas}]
# mge of lens profile
lensModel = LensModel(mass_profile_list)
r_array = np.logspace(-2, 2, 200)
kappa_r = lensModel.kappa(r_array, 0, kwargs_profile)
amps, sigmas, norm = mge.mge_1d(r_array, kappa_r, N=20)
mass_profile_list_mge = ['MULTI_GAUSSIAN_KAPPA']
kwargs_profile_mge = [{'amp': amps, 'sigma': sigmas}]
galkin = Galkin(mass_profile_list, light_profile_list, aperture_type=aperture_type, anisotropy_model=anisotropy_type, fwhm=psf_fwhm, kwargs_cosmo=kwargs_cosmo)
sigma_v = galkin.vel_disp(kwargs_profile, kwargs_light, kwargs_anisotropy, kwargs_aperture)
galkin = Galkin(mass_profile_list_mge, light_profile_list_mge, aperture_type=aperture_type, anisotropy_model=anisotropy_type, fwhm=psf_fwhm, kwargs_cosmo=kwargs_cosmo)
sigma_v2 = galkin.vel_disp(kwargs_profile_mge, kwargs_light_mge, kwargs_anisotropy, kwargs_aperture)
print(sigma_v, sigma_v2, 'sigma_v Galkin, sigma_v MGEn')
print((sigma_v/sigma_v2)**2)
npt.assert_almost_equal((sigma_v-sigma_v2)/sigma_v2, 0, decimal=2)
def test_compare_power_law(self):
"""
compare power-law profiles analytical vs. numerical
:return:
"""
# light profile
light_profile_list = ['HERNQUIST']
r_eff = 1.5
kwargs_light = [{'Rs': r_eff, 'sigma0': 1.}] # effective half light radius (2d projected) in arcsec
# 0.551 *
# mass profile
mass_profile_list = ['SPP']
theta_E = 1.2
gamma = 2.
kwargs_profile = [{'theta_E': theta_E, 'gamma': gamma}] # Einstein radius (arcsec) and power-law slope
# anisotropy profile
anisotropy_type = 'OsipkovMerritt'
r_ani = 2.
kwargs_anisotropy = {'r_ani': r_ani} # anisotropy radius [arcsec]
# aperture as slit
aperture_type = 'slit'
length = 1.
width = 0.3
kwargs_aperture = {'length': length, 'width': width, 'center_ra': 0, 'center_dec': 0, 'angle': 0}
psf_fwhm = 1. # Gaussian FWHM psf
kwargs_cosmo = {'D_d': 1000, 'D_s': 1500, 'D_ds': 800}
kwargs_numerics = {'sampling_number': 1000, 'interpol_grid_num': 500, 'log_integration': True,
'max_integrate': 100}
galkin = Galkin(mass_profile_list, light_profile_list, aperture_type=aperture_type, anisotropy_model=anisotropy_type, fwhm=psf_fwhm, kwargs_cosmo=kwargs_cosmo, kwargs_numerics=kwargs_numerics)
sigma_v = galkin.vel_disp(kwargs_profile, kwargs_light, kwargs_anisotropy, kwargs_aperture)
kwargs_numerics = {'sampling_number': 1000, 'interpol_grid_num': 500, 'log_integration': False,
'max_integrate': 10}
galkin = Galkin(mass_profile_list, light_profile_list, aperture_type=aperture_type, anisotropy_model=anisotropy_type, fwhm=psf_fwhm, kwargs_cosmo=kwargs_cosmo, kwargs_numerics=kwargs_numerics)
sigma_v_lin = galkin.vel_disp(kwargs_profile, kwargs_light, kwargs_anisotropy, kwargs_aperture)
los_disp = Velocity_dispersion(beta_const=False, b_prior=False, kwargs_cosmo=kwargs_cosmo)
sigma_v2 = los_disp.vel_disp(gamma, theta_E, r_eff/0.551, aniso_param=r_ani, R_slit=length, dR_slit=width,
FWHM=psf_fwhm, num=1000)
print(sigma_v, sigma_v_lin, sigma_v2, 'sigma_v Galkin (log and linear), sigma_v los dispersion')
npt.assert_almost_equal(sigma_v2/sigma_v, 1, decimal=2)
def test_log_vs_linear_integral(self):
# light profile
light_profile_list = ['HERNQUIST']
r_eff = .5
kwargs_light = [{'Rs': r_eff, 'sigma0': 1.}] # effective half light radius (2d projected) in arcsec
# 0.551 *
# mass profile
mass_profile_list = ['SPP']
theta_E = 1.2
gamma = 2.
kwargs_profile = [{'theta_E': theta_E, 'gamma': gamma}] # Einstein radius (arcsec) and power-law slope
# anisotropy profile
anisotropy_type = 'OsipkovMerritt'
r_ani = 2.
kwargs_anisotropy = {'r_ani': r_ani} # anisotropy radius [arcsec]
# aperture as slit
aperture_type = 'slit'
length = 3.8
width = 0.9
kwargs_aperture = {'length': length, 'width': width, 'center_ra': 0, 'center_dec': 0, 'angle': 0}
psf_fwhm = 0.7 # Gaussian FWHM psf
kwargs_cosmo = {'D_d': 1000, 'D_s': 1500, 'D_ds': 800}
kwargs_numerics_log = {'sampling_number': 1000, 'interpol_grid_num': 500, 'log_integration': True,
'max_integrate': 10}
kwargs_numerics_linear = {'sampling_number': 1000, 'interpol_grid_num': 500, 'log_integration': False,
'max_integrate': 10}
galkin_linear = Galkin(mass_profile_list, light_profile_list, aperture_type=aperture_type, anisotropy_model=anisotropy_type, fwhm=psf_fwhm, kwargs_cosmo=kwargs_cosmo, kwargs_numerics=kwargs_numerics_linear)
sigma_v = galkin_linear.vel_disp(kwargs_profile, kwargs_light, kwargs_anisotropy, kwargs_aperture)
galkin_log = Galkin(mass_profile_list, light_profile_list, aperture_type=aperture_type,
anisotropy_model=anisotropy_type, fwhm=psf_fwhm, kwargs_cosmo=kwargs_cosmo, kwargs_numerics=kwargs_numerics_log)
sigma_v2 = galkin_log.vel_disp(kwargs_profile, kwargs_light, kwargs_anisotropy, kwargs_aperture)
print(sigma_v, sigma_v2, 'sigma_v linear, sigma_v log')
print((sigma_v/sigma_v2)**2)
npt.assert_almost_equal(sigma_v/sigma_v2, 1, decimal=2)
def velocity_dispersion_numerical(self,
kwargs_lens,
kwargs_lens_light,
kwargs_anisotropy,
kwargs_aperture,
psf_fwhm,
aperture_type,
anisotropy_model,
r_eff,
psf_type='GAUSSIAN',
moffat_beta=2.6,
kwargs_numerics={},
MGE_light=False,
MGE_mass=False,
lens_model_kinematics_bool=None,
light_model_kinematics_bool=None,
Hernquist_approx=False,
kappa_ext=0):
"""
Computes the LOS velocity dispersion of the deflector galaxy with arbitrary combinations of light and mass models.
For a detailed description, visit the description of the Galkin() class.
Additionaly to executing the Galkin routine, it has an optional Multi-Gaussian-Expansion decomposition of lens
and light models that do not have a three-dimensional distribution built in, such as Sersic profiles etc.
The center of all the lens and lens light models that are part of the kinematic estimate must be centered on the
same point.
:param kwargs_lens: lens model parameters
:param kwargs_lens_light: lens light parameters
:param kwargs_anisotropy: anisotropy parameters (see Galkin module)
:param kwargs_aperture: aperture parameters (see Galkin module)
:param psf_fwhm: full width at half maximum of the seeing (Gaussian form)
:param psf_type: string, point spread functino type, current support for 'GAUSSIAN' and 'MOFFAT'
:param moffat_beta: float, beta parameter of Moffat profile
:param aperture_type: type of aperture (see Galkin module
:param anisotropy_model: stellar anisotropy model (see Galkin module)
:param r_eff: a rough estimate of the half light radius of the lens light in case of computing the MGE of the
light profile
:param kwargs_numerics: keyword arguments that contain numerical options (see Galkin module)
:param MGE_light: bool, if true performs the MGE for the light distribution
:param MGE_mass: bool, if true performs the MGE for the mass distribution
:param lens_model_kinematics_bool: bool list of length of the lens model. Only takes a subset of all the models
as part of the kinematics computation (can be used to ignore substructure, shear etc that do not describe the
main deflector potential
:param light_model_kinematics_bool: bool list of length of the light model. Only takes a subset of all the models
as part of the kinematics computation (can be used to ignore light components that do not describe the main
deflector
:param Hernquist_approx: bool, if True, uses a Hernquist light profile matched to the half light radius of the deflector light profile to compute the kinematics
:param kappa_ext: external convergence not accounted in the lens models
:return: LOS velocity dispersion [km/s]
"""
kwargs_cosmo = {
'D_d': self.lensCosmo.D_d,
'D_s': self.lensCosmo.D_s,
'D_ds': self.lensCosmo.D_ds
}
mass_profile_list, kwargs_profile, light_profile_list, kwargs_light = self.kinematic_profiles(
kwargs_lens,
kwargs_lens_light,
r_eff=r_eff,
MGE_light=MGE_light,
MGE_mass=MGE_mass,
lens_model_kinematics_bool=lens_model_kinematics_bool,
light_model_kinematics_bool=light_model_kinematics_bool,
Hernquist_approx=Hernquist_approx)
galkin = Galkin(mass_profile_list,
light_profile_list,
aperture_type=aperture_type,
anisotropy_model=anisotropy_model,
fwhm=psf_fwhm,
psf_type=psf_type,
moffat_beta=moffat_beta,
kwargs_cosmo=kwargs_cosmo,
**kwargs_numerics)
sigma = galkin.vel_disp(kwargs_profile, kwargs_light,
kwargs_anisotropy, kwargs_aperture)
sigma *= np.sqrt(1 - kappa_ext)
return sigma
def velocity_disperson_numerical(self,
kwargs_lens,
kwargs_lens_light,
kwargs_anisotropy,
kwargs_aperture,
psf_fwhm,
aperture_type,
anisotropy_model,
r_eff=1.,
kwargs_numerics={},
MGE_light=False,
MGE_mass=False):
"""
:param kwargs_lens:
:param kwargs_lens_light:
:param kwargs_anisotropy:
:param kwargs_aperature:
:return:
"""
kwargs_cosmo = {
'D_d': self.lensCosmo.D_d,
'D_s': self.lensCosmo.D_s,
'D_ds': self.lensCosmo.D_ds
}
mass_profile_list = []
kwargs_profile = []
lens_model_internal_bool = self.kwargs_options.get(
'lens_model_deflector_bool', [True] * len(kwargs_lens))
for i, lens_model in enumerate(self.kwargs_options['lens_model_list']):
if lens_model_internal_bool[i]:
mass_profile_list.append(lens_model)
kwargs_lens_i = {
k: v
for k, v in kwargs_lens[i].items()
if not k in ['center_x', 'center_y']
}
kwargs_profile.append(kwargs_lens_i)
if MGE_mass is True:
massModel = LensModelExtensions(lens_model_list=mass_profile_list)
theta_E = massModel.effective_einstein_radius(kwargs_lens)
r_array = np.logspace(-4, 2, 200) * theta_E
mass_r = massModel.kappa(r_array, 0, kwargs_profile)
amps, sigmas, norm = mge.mge_1d(r_array, mass_r, N=20)
mass_profile_list = ['MULTI_GAUSSIAN_KAPPA']
kwargs_profile = [{'amp': amps, 'sigma': sigmas}]
light_profile_list = []
kwargs_light = []
lens_light_model_internal_bool = self.kwargs_options.get(
'light_model_deflector_bool', [True] * len(kwargs_lens_light))
for i, light_model in enumerate(
self.kwargs_options['lens_light_model_list']):
if lens_light_model_internal_bool[i]:
light_profile_list.append(light_model)
kwargs_Lens_light_i = {
k: v
for k, v in kwargs_lens_light[i].items()
if not k in ['center_x', 'center_y']
}
if 'q' in kwargs_Lens_light_i:
kwargs_Lens_light_i['q'] = 1
kwargs_light.append(kwargs_Lens_light_i)
if MGE_light is True:
lightModel = LightModel(light_profile_list)
r_array = np.logspace(-3, 2, 200) * r_eff * 2
flux_r = lightModel.surface_brightness(r_array, 0, kwargs_light)
amps, sigmas, norm = mge.mge_1d(r_array, flux_r, N=20)
light_profile_list = ['MULTI_GAUSSIAN']
kwargs_light = [{'amp': amps, 'sigma': sigmas}]
galkin = Galkin(mass_profile_list,
light_profile_list,
aperture_type=aperture_type,
anisotropy_model=anisotropy_model,
fwhm=psf_fwhm,
kwargs_cosmo=kwargs_cosmo,
kwargs_numerics=kwargs_numerics)
sigma_v = galkin.vel_disp(kwargs_profile,
kwargs_light,
kwargs_anisotropy,
kwargs_aperture,
r_eff=r_eff)
return sigma_v
def velocity_dispersion_numerical(self,
kwargs_lens,
kwargs_lens_light,
kwargs_anisotropy,
kwargs_aperture,
kwargs_psf,
anisotropy_model,
r_eff=None,
theta_E=None,
kwargs_numerics={},
MGE_light=False,
kwargs_mge_light=None,
MGE_mass=False,
kwargs_mge_mass=None,
Hernquist_approx=False,
kappa_ext=0):
"""
Computes the LOS velocity dispersion of the deflector galaxy with arbitrary combinations of light and mass models.
For a detailed description, visit the description of the Galkin() class.
Additionally to executing the GalKin routine, it has an optional Multi-Gaussian-Expansion decomposition of lens
and light models that do not have a three-dimensional distribution built in, such as Sersic profiles etc.
The center of all the lens and lens light models that are part of the kinematic estimate must be centered on the
same point.
:param kwargs_lens: lens model parameters
:param kwargs_lens_light: lens light parameters
:param kwargs_anisotropy: anisotropy parameters (see Galkin module)
:param kwargs_aperture: aperture parameters (see Galkin module)
:param kwargs_psf: seeing conditions and model (see GalKin module)
:param anisotropy_model: stellar anisotropy model (see Galkin module)
:param r_eff: a rough estimate of the half light radius of the lens light in case of computing the MGE of the
light profile
:param theta_E: a rough estimate of the Einstein radius when performing the MGE of the deflector
:param kwargs_numerics: keyword arguments that contain numerical options (see Galkin module)
:param MGE_light: bool, if true performs the MGE for the light distribution
:param MGE_mass: bool, if true performs the MGE for the mass distribution
:param Hernquist_approx: bool, if True, uses a Hernquist light profile matched to the half light radius of the deflector light profile to compute the kinematics
:param kappa_ext: external convergence not accounted in the lens models
:param kwargs_mge_light: keyword arguments that go into the MGE decomposition routine
:param kwargs_mge_mass: keyword arguments that go into the MGE decomposition routine
:return: LOS velocity dispersion [km/s]
"""
mass_profile_list, kwargs_profile = self.kinematic_lens_profiles(
kwargs_lens,
MGE_fit=MGE_mass,
theta_E=theta_E,
model_kinematics_bool=self._lens_model_kinematics_bool,
kwargs_mge=kwargs_mge_mass)
light_profile_list, kwargs_light = self.kinematic_light_profile(
kwargs_lens_light,
r_eff=r_eff,
MGE_fit=MGE_light,
kwargs_mge=kwargs_mge_light,
model_kinematics_bool=self._light_model_kinematics_bool,
Hernquist_approx=Hernquist_approx)
galkin = Galkin(mass_profile_list,
light_profile_list,
kwargs_aperture=kwargs_aperture,
kwargs_psf=kwargs_psf,
anisotropy_model=anisotropy_model,
kwargs_cosmo=self._kwargs_cosmo,
**kwargs_numerics)
sigma = galkin.vel_disp(kwargs_profile, kwargs_light,
kwargs_anisotropy)
sigma *= np.sqrt(1 - kappa_ext)
return sigma
def velocity_dispersion_numerical(self,
kwargs_lens,
kwargs_lens_light,
kwargs_anisotropy,
kwargs_aperture,
psf_fwhm,
aperture_type,
anisotropy_model,
r_eff=None,
kwargs_numerics={},
MGE_light=False,
MGE_mass=False,
lens_model_kinematics_bool=None,
light_model_kinematics_bool=None,
Hernquist_approx=False):
"""
Computes the LOS velocity dispersion of the deflector galaxy with arbitrary combinations of light and mass models.
For a detailed description, visit the description of the Galkin() class.
Additionaly to executing the Galkin routine, it has an optional Multi-Gaussian-Expansion decomposition of lens
and light models that do not have a three-dimensional distribution built in, such as Sersic profiles etc.
The center of all the lens and lens light models that are part of the kinematic estimate must be centered on the
same point.
:param kwargs_lens: lens model parameters
:param kwargs_lens_light: lens light parameters
:param kwargs_anisotropy: anisotropy parameters (see Galkin module)
:param kwargs_aperture: aperture parameters (see Galkin module)
:param psf_fwhm: full width at half maximum of the seeing (Gaussian form)
:param aperture_type: type of aperture (see Galkin module
:param anisotropy_model: stellar anisotropy model (see Galkin module)
:param r_eff: a rough estimate of the half light radius of the lens light in case of computing the MGE of the
light profile
:param kwargs_numerics: keyword arguments that contain numerical options (see Galkin module)
:param MGE_light: bool, if true performs the MGE for the light distribution
:param MGE_mass: bool, if true performs the MGE for the mass distribution
:param lens_model_kinematics_bool: bool list of length of the lens model. Only takes a subset of all the models
as part of the kinematics computation (can be used to ignore substructure, shear etc that do not describe the
main deflector potential
:param light_model_kinematics_bool: bool list of length of the light model. Only takes a subset of all the models
as part of the kinematics computation (can be used to ignore light components that do not describe the main
deflector
:return: LOS velocity dispersion [km/s]
"""
kwargs_cosmo = {
'D_d': self.lensCosmo.D_d,
'D_s': self.lensCosmo.D_s,
'D_ds': self.lensCosmo.D_ds
}
mass_profile_list = []
kwargs_profile = []
if lens_model_kinematics_bool is None:
lens_model_kinematics_bool = [True] * len(kwargs_lens)
for i, lens_model in enumerate(self.kwargs_options['lens_model_list']):
if lens_model_kinematics_bool[i] is True:
mass_profile_list.append(lens_model)
if lens_model in ['INTERPOL', 'INTERPOL_SCLAED']:
center_x, center_y = self._lensModelExt.lens_center(
kwargs_lens, k=i)
kwargs_lens_i = copy.deepcopy(kwargs_lens[i])
kwargs_lens_i['grid_interp_x'] -= center_x
kwargs_lens_i['grid_interp_y'] -= center_y
else:
kwargs_lens_i = {
k: v
for k, v in kwargs_lens[i].items()
if not k in ['center_x', 'center_y']
}
kwargs_profile.append(kwargs_lens_i)
if MGE_mass is True:
lensModel = LensModel(lens_model_list=mass_profile_list)
massModel = LensModelExtensions(lensModel)
theta_E = massModel.effective_einstein_radius(kwargs_profile)
r_array = np.logspace(-4, 2, 200) * theta_E
mass_r = lensModel.kappa(r_array, np.zeros_like(r_array),
kwargs_profile)
amps, sigmas, norm = mge.mge_1d(r_array, mass_r, N=20)
mass_profile_list = ['MULTI_GAUSSIAN_KAPPA']
kwargs_profile = [{'amp': amps, 'sigma': sigmas}]
light_profile_list = []
kwargs_light = []
if light_model_kinematics_bool is None:
light_model_kinematics_bool = [True] * len(kwargs_lens_light)
for i, light_model in enumerate(
self.kwargs_options['lens_light_model_list']):
if light_model_kinematics_bool[i]:
light_profile_list.append(light_model)
kwargs_lens_light_i = {
k: v
for k, v in kwargs_lens_light[i].items()
if not k in ['center_x', 'center_y']
}
if 'q' in kwargs_lens_light_i:
kwargs_lens_light_i['q'] = 1
kwargs_light.append(kwargs_lens_light_i)
if r_eff is None:
lensAnalysis = LensAnalysis(
{'lens_light_model_list': light_profile_list})
r_eff = lensAnalysis.half_light_radius_lens(
kwargs_light, model_bool_list=light_model_kinematics_bool)
if Hernquist_approx is True:
light_profile_list = ['HERNQUIST']
kwargs_light = [{'Rs': r_eff, 'amp': 1.}]
else:
if MGE_light is True:
lightModel = LightModel(light_profile_list)
r_array = np.logspace(-3, 2, 200) * r_eff * 2
flux_r = lightModel.surface_brightness(r_array, 0,
kwargs_light)
amps, sigmas, norm = mge.mge_1d(r_array, flux_r, N=20)
light_profile_list = ['MULTI_GAUSSIAN']
kwargs_light = [{'amp': amps, 'sigma': sigmas}]
galkin = Galkin(mass_profile_list,
light_profile_list,
aperture_type=aperture_type,
anisotropy_model=anisotropy_model,
fwhm=psf_fwhm,
kwargs_cosmo=kwargs_cosmo,
**kwargs_numerics)
sigma2 = galkin.vel_disp(kwargs_profile, kwargs_light,
kwargs_anisotropy, kwargs_aperture)
return sigma2
def test_mge_power_law_lens(self):
"""
compare power-law profiles analytical vs. numerical
:return:
"""
# anisotropy profile
anisotropy_type = 'OsipkovMerritt'
r_ani = 2.
kwargs_anisotropy = {'r_ani': r_ani} # anisotropy radius [arcsec]
# aperture as slit
aperture_type = 'slit'
length = 3.8
width = 0.9
kwargs_aperture = {
'length': length,
'width': width,
'center_ra': 0,
'center_dec': 0,
'angle': 0,
'aperture_type': aperture_type
}
psf_fwhm = 0.7 # Gaussian FWHM psf
kwargs_cosmo = {'D_d': 1000, 'D_s': 1500, 'D_ds': 800}
# light profile
light_profile_list = ['HERNQUIST']
r_eff = 1.8
kwargs_light = [{
'Rs': r_eff,
'amp': 1.
}] # effective half light radius (2d projected) in arcsec
# mass profile
mass_profile_list = ['SPP']
theta_E = 1.2
gamma = 2.
kwargs_profile = [{
'theta_E': theta_E,
'gamma': gamma
}] # Einstein radius (arcsec) and power-law slope
# mge of lens profile
lensModel = LensModel(mass_profile_list)
r_array = np.logspace(-2, 1, 100) * theta_E
kappa_r = lensModel.kappa(r_array, 0, kwargs_profile)
amps, sigmas, norm = mge.mge_1d(r_array, kappa_r, N=20)
mass_profile_list_mge = ['MULTI_GAUSSIAN_KAPPA']
kwargs_profile_mge = [{'amp': amps, 'sigma': sigmas}]
kwargs_psf = {'psf_type': 'GAUSSIAN', 'fwhm': psf_fwhm}
galkin = Galkin(mass_profile_list,
light_profile_list,
anisotropy_model=anisotropy_type,
kwargs_psf=kwargs_psf,
kwargs_cosmo=kwargs_cosmo,
kwargs_aperture=kwargs_aperture)
sigma_v = galkin.vel_disp(kwargs_profile, kwargs_light,
kwargs_anisotropy)
galkin = Galkin(mass_profile_list_mge,
light_profile_list,
anisotropy_model=anisotropy_type,
kwargs_psf=kwargs_psf,
kwargs_cosmo=kwargs_cosmo,
kwargs_aperture=kwargs_aperture)
sigma_v2 = galkin.vel_disp(kwargs_profile_mge, kwargs_light,
kwargs_anisotropy)
print(sigma_v, sigma_v2, 'sigma_v Galkin, sigma_v MGEn')
print((sigma_v / sigma_v2)**2)
npt.assert_almost_equal((sigma_v - sigma_v2) / sigma_v2, 0, decimal=2)