Source code for astrophot.models.sersic_model

import torch
import numpy as np

from .galaxy_model_object import Galaxy_Model
from .warp_model import Warp_Galaxy
from .ray_model import Ray_Galaxy
from .wedge_model import Wedge_Galaxy
from .psf_model_object import PSF_Model
from .superellipse_model import SuperEllipse_Galaxy, SuperEllipse_Warp
from .foureirellipse_model import FourierEllipse_Galaxy, FourierEllipse_Warp
from ._shared_methods import (
    parametric_initialize,
    parametric_segment_initialize,
    select_target,
)
from ..utils.decorators import ignore_numpy_warnings, default_internal
from ..utils.initialize import isophotes
from ..utils.parametric_profiles import sersic_torch, sersic_np
from ..utils.conversions.coordinates import Rotate_Cartesian
from ..utils.conversions.functions import sersic_Ie_to_flux_torch, general_uncertainty_prop


__all__ = [
    "Sersic_Galaxy",
    "Sersic_PSF",
    "Sersic_Warp",
    "Sersic_SuperEllipse",
    "Sersic_FourierEllipse",
    "Sersic_Ray",
    "Sersic_Wedge",
    "Sersic_SuperEllipse_Warp",
    "Sersic_FourierEllipse_Warp",
]


def _x0_func(model, R, F):
    return 2.0, R[4], F[4]


def _wrap_sersic(R, n, r, i):
    return sersic_np(R, n, r, 10 ** (i))


[docs] class Sersic_Galaxy(Galaxy_Model): """basic galaxy model with a sersic profile for the radial light profile. The functional form of the Sersic profile is defined as: I(R) = Ie * exp(- bn((R/Re)^(1/n) - 1)) where I(R) is the brightness profile as a function of semi-major axis, R is the semi-major axis length, Ie is the brightness as the half light radius, bn is a function of n and is not involved in the fit, Re is the half light radius, and n is the sersic index which controls the shape of the profile. Parameters: n: Sersic index which controls the shape of the brightness profile Ie: brightness at the half light radius, represented as the log of the brightness divided by pixel scale squared. Re: half light radius """ model_type = f"sersic {Galaxy_Model.model_type}" parameter_specs = { "n": {"units": "none", "limits": (0.36, 8), "uncertainty": 0.05}, "Re": {"units": "arcsec", "limits": (0, None)}, "Ie": {"units": "log10(flux/arcsec^2)"}, } _parameter_order = Galaxy_Model._parameter_order + ("n", "Re", "Ie") useable = True
[docs] @torch.no_grad() @ignore_numpy_warnings @select_target @default_internal def initialize(self, target=None, parameters=None, **kwargs): super().initialize(target=target, parameters=parameters) parametric_initialize( self, parameters, target, _wrap_sersic, ("n", "Re", "Ie"), _x0_func )
[docs] @default_internal def total_flux(self, parameters=None): return sersic_Ie_to_flux_torch( 10 ** parameters["Ie"].value, parameters["n"].value, parameters["Re"].value, parameters["q"].value, )
[docs] @default_internal def total_flux_uncertainty(self, parameters=None): return general_uncertainty_prop( (10 ** parameters["Ie"].value, parameters["n"].value, parameters["Re"].value, parameters["q"].value ), ((10 ** parameters["Ie"].value) * parameters["Ie"].uncertainty * torch.log(10 * torch.ones_like(parameters["Ie"].value)), parameters["n"].uncertainty, parameters["Re"].uncertainty, parameters["q"].uncertainty ), sersic_Ie_to_flux_torch )
def _integrate_reference(self, image_data, image_header, parameters): tot = self.total_flux(parameters) return tot / image_data.numel() from ._shared_methods import sersic_radial_model as radial_model
[docs] class Sersic_PSF(PSF_Model): """basic point source model with a sersic profile for the radial light profile. The functional form of the Sersic profile is defined as: I(R) = Ie * exp(- bn((R/Re)^(1/n) - 1)) where I(R) is the brightness profile as a function of semi-major axis, R is the semi-major axis length, Ie is the brightness as the half light radius, bn is a function of n and is not involved in the fit, Re is the half light radius, and n is the sersic index which controls the shape of the profile. Parameters: n: Sersic index which controls the shape of the brightness profile Ie: brightness at the half light radius, represented as the log of the brightness divided by pixel scale squared. Re: half light radius """ model_type = f"sersic {PSF_Model.model_type}" parameter_specs = { "n": {"units": "none", "limits": (0.36, 8), "uncertainty": 0.05}, "Re": {"units": "arcsec", "limits": (0, None)}, "Ie": {"units": "log10(flux/arcsec^2)", "value": 0., "uncertainty": 0., "locked": True}, } _parameter_order = PSF_Model._parameter_order + ("n", "Re", "Ie") useable = True model_integrated = False
[docs] @torch.no_grad() @ignore_numpy_warnings @select_target @default_internal def initialize(self, target=None, parameters=None, **kwargs): super().initialize(target=target, parameters=parameters) parametric_initialize( self, parameters, target, _wrap_sersic, ("n", "Re", "Ie"), _x0_func )
from ._shared_methods import sersic_radial_model as radial_model from ._shared_methods import radial_evaluate_model as evaluate_model
[docs] class Sersic_SuperEllipse(SuperEllipse_Galaxy): """super ellipse galaxy model with a sersic profile for the radial light profile. The functional form of the Sersic profile is defined as: I(R) = Ie * exp(- bn((R/Re)^(1/n) - 1)) where I(R) is the brightness profile as a function of semi-major axis, R is the semi-major axis length, Ie is the brightness as the half light radius, bn is a function of n and is not involved in the fit, Re is the half light radius, and n is the sersic index which controls the shape of the profile. Parameters: n: Sersic index which controls the shape of the brightness profile Ie: brightness at the half light radius, represented as the log of the brightness divided by pixel scale squared. Re: half light radius """ model_type = f"sersic {SuperEllipse_Galaxy.model_type}" parameter_specs = { "Ie": {"units": "log10(flux/arcsec^2)"}, "n": {"units": "none", "limits": (0.36, 8), "uncertainty": 0.05}, "Re": {"units": "arcsec", "limits": (0, None)}, } _parameter_order = SuperEllipse_Galaxy._parameter_order + ("n", "Re", "Ie") useable = True
[docs] @torch.no_grad() @ignore_numpy_warnings @select_target @default_internal def initialize(self, target=None, parameters=None, **kwargs): super().initialize(target=target, parameters=parameters) parametric_initialize( self, parameters, target, _wrap_sersic, ("n", "Re", "Ie"), _x0_func )
from ._shared_methods import sersic_radial_model as radial_model
[docs] class Sersic_SuperEllipse_Warp(SuperEllipse_Warp): """super ellipse warp galaxy model with a sersic profile for the radial light profile. The functional form of the Sersic profile is defined as: I(R) = Ie * exp(- bn((R/Re)^(1/n) - 1)) where I(R) is the brightness profile as a function of semi-major axis, R is the semi-major axis length, Ie is the brightness as the half light radius, bn is a function of n and is not involved in the fit, Re is the half light radius, and n is the sersic index which controls the shape of the profile. Parameters: n: Sersic index which controls the shape of the brightness profile Ie: brightness at the half light radius, represented as the log of the brightness divided by pixel scale squared. Re: half light radius """ model_type = f"sersic {SuperEllipse_Warp.model_type}" parameter_specs = { "Ie": {"units": "log10(flux/arcsec^2)"}, "n": {"units": "none", "limits": (0.36, 8), "uncertainty": 0.05}, "Re": {"units": "arcsec", "limits": (0, None)}, } _parameter_order = SuperEllipse_Warp._parameter_order + ("n", "Re", "Ie") useable = True
[docs] @torch.no_grad() @ignore_numpy_warnings @select_target @default_internal def initialize(self, target=None, parameters=None, **kwargs): super().initialize(target=target, parameters=parameters) parametric_initialize( self, parameters, target, _wrap_sersic, ("n", "Re", "Ie"), _x0_func )
from ._shared_methods import sersic_radial_model as radial_model
[docs] class Sersic_FourierEllipse(FourierEllipse_Galaxy): """fourier mode perturbations to ellipse galaxy model with a sersic profile for the radial light profile. The functional form of the Sersic profile is defined as: I(R) = Ie * exp(- bn((R/Re)^(1/n) - 1)) where I(R) is the brightness profile as a function of semi-major axis, R is the semi-major axis length, Ie is the brightness as the half light radius, bn is a function of n and is not involved in the fit, Re is the half light radius, and n is the sersic index which controls the shape of the profile. Parameters: n: Sersic index which controls the shape of the brightness profile Ie: brightness at the half light radius, represented as the log of the brightness divided by pixel scale squared. Re: half light radius """ model_type = f"sersic {FourierEllipse_Galaxy.model_type}" parameter_specs = { "Ie": {"units": "log10(flux/arcsec^2)"}, "n": {"units": "none", "limits": (0.36, 8), "uncertainty": 0.05}, "Re": {"units": "arcsec", "limits": (0, None)}, } _parameter_order = FourierEllipse_Galaxy._parameter_order + ("n", "Re", "Ie") useable = True
[docs] @torch.no_grad() @ignore_numpy_warnings @select_target @default_internal def initialize(self, target=None, parameters=None, **kwargs): super().initialize(target=target, parameters=parameters) parametric_initialize( self, parameters, target, _wrap_sersic, ("n", "Re", "Ie"), _x0_func )
from ._shared_methods import sersic_radial_model as radial_model
[docs] class Sersic_FourierEllipse_Warp(FourierEllipse_Warp): """fourier mode perturbations to ellipse galaxy model with a sersic profile for the radial light profile. The functional form of the Sersic profile is defined as: I(R) = Ie * exp(- bn((R/Re)^(1/n) - 1)) where I(R) is the brightness profile as a function of semi-major axis, R is the semi-major axis length, Ie is the brightness as the half light radius, bn is a function of n and is not involved in the fit, Re is the half light radius, and n is the sersic index which controls the shape of the profile. Parameters: n: Sersic index which controls the shape of the brightness profile Ie: brightness at the half light radius, represented as the log of the brightness divided by pixel scale squared. Re: half light radius """ model_type = f"sersic {FourierEllipse_Warp.model_type}" parameter_specs = { "Ie": {"units": "log10(flux/arcsec^2)"}, "n": {"units": "none", "limits": (0.36, 8), "uncertainty": 0.05}, "Re": {"units": "arcsec", "limits": (0, None)}, } _parameter_order = FourierEllipse_Warp._parameter_order + ("n", "Re", "Ie") useable = True
[docs] @torch.no_grad() @ignore_numpy_warnings @select_target @default_internal def initialize(self, target=None, parameters=None, **kwargs): super().initialize(target=target, parameters=parameters) parametric_initialize( self, parameters, target, _wrap_sersic, ("n", "Re", "Ie"), _x0_func )
from ._shared_methods import sersic_radial_model as radial_model
[docs] class Sersic_Warp(Warp_Galaxy): """warped coordinate galaxy model with a sersic profile for the radial light model. The functional form of the Sersic profile is defined as: I(R) = Ie * exp(- bn((R/Re)^(1/n) - 1)) where I(R) is the brightness profile as a function of semi-major axis, R is the semi-major axis length, Ie is the brightness as the half light radius, bn is a function of n and is not involved in the fit, Re is the half light radius, and n is the sersic index which controls the shape of the profile. Parameters: n: Sersic index which controls the shape of the brightness profile Ie: brightness at the half light radius, represented as the log of the brightness divided by pixel scale squared. Re: half light radius """ model_type = f"sersic {Warp_Galaxy.model_type}" parameter_specs = { "Ie": {"units": "log10(flux/arcsec^2)"}, "n": {"units": "none", "limits": (0.36, 8), "uncertainty": 0.05}, "Re": {"units": "arcsec", "limits": (0, None)}, } _parameter_order = Warp_Galaxy._parameter_order + ("n", "Re", "Ie") useable = True
[docs] @torch.no_grad() @ignore_numpy_warnings @select_target @default_internal def initialize(self, target=None, parameters=None, **kwargs): super().initialize(target=target, parameters=parameters) parametric_initialize( self, parameters, target, _wrap_sersic, ("n", "Re", "Ie"), _x0_func )
from ._shared_methods import sersic_radial_model as radial_model
[docs] class Sersic_Ray(Ray_Galaxy): """ray galaxy model with a sersic profile for the radial light model. The functional form of the Sersic profile is defined as: I(R) = Ie * exp(- bn((R/Re)^(1/n) - 1)) where I(R) is the brightness profile as a function of semi-major axis, R is the semi-major axis length, Ie is the brightness as the half light radius, bn is a function of n and is not involved in the fit, Re is the half light radius, and n is the sersic index which controls the shape of the profile. Parameters: n: Sersic index which controls the shape of the brightness profile Ie: brightness at the half light radius, represented as the log of the brightness divided by pixel scale squared. Re: half light radius """ model_type = f"sersic {Ray_Galaxy.model_type}" parameter_specs = { "Ie": {"units": "log10(flux/arcsec^2)"}, "n": {"units": "none", "limits": (0.36, 8), "uncertainty": 0.05}, "Re": {"units": "arcsec", "limits": (0, None)}, } _parameter_order = Ray_Galaxy._parameter_order + ("n", "Re", "Ie") useable = True
[docs] @torch.no_grad() @ignore_numpy_warnings @select_target @default_internal def initialize(self, target=None, parameters=None, **kwargs): super().initialize(target=target, parameters=parameters) parametric_segment_initialize( model=self, target=target, parameters=parameters, prof_func=_wrap_sersic, params=("n", "Re", "Ie"), x0_func=_x0_func, segments=self.rays, )
from ._shared_methods import sersic_iradial_model as iradial_model
[docs] class Sersic_Wedge(Wedge_Galaxy): """wedge galaxy model with a sersic profile for the radial light model. The functional form of the Sersic profile is defined as: I(R) = Ie * exp(- bn((R/Re)^(1/n) - 1)) where I(R) is the brightness profile as a function of semi-major axis, R is the semi-major axis length, Ie is the brightness as the half light radius, bn is a function of n and is not involved in the fit, Re is the half light radius, and n is the sersic index which controls the shape of the profile. Parameters: n: Sersic index which controls the shape of the brightness profile Ie: brightness at the half light radius, represented as the log of the brightness divided by pixel scale squared. Re: half light radius """ model_type = f"sersic {Wedge_Galaxy.model_type}" parameter_specs = { "Ie": {"units": "log10(flux/arcsec^2)"}, "n": {"units": "none", "limits": (0.36, 8), "uncertainty": 0.05}, "Re": {"units": "arcsec", "limits": (0, None)}, } _parameter_order = Wedge_Galaxy._parameter_order + ("n", "Re", "Ie") useable = True
[docs] @torch.no_grad() @ignore_numpy_warnings @select_target @default_internal def initialize(self, target=None, parameters=None, **kwargs): super().initialize(target=target, parameters=parameters) parametric_segment_initialize( model=self, parameters=parameters, target=target, prof_func=_wrap_sersic, params=("n", "Re", "Ie"), x0_func=_x0_func, segments=self.wedges, )
from ._shared_methods import sersic_iradial_model as iradial_model