autogalaxy.profiles.light.standard.ExponentialSph#

class ExponentialSph[source]#

Bases: Exponential

The spherical exponential profile.

This is a specific case of the elliptical Sersic profile where sersic_index=1.0.

Parameters:
  • centre (Tuple[float, float]) – The (y,x) arc-second coordinates of the profile centre.

  • intensity (float) – Overall intensity normalisation of the light profile (units are dimensionless and derived from the data the light profile’s image is compared too, which is expected to be electrons per second).

  • effective_radius (float) – The circular radius containing half the light of this profile.

Methods

angle_to_profile_grid_from

The angle between each angle theta on the grid and the profile, in radians.

blurred_image_2d_from

Evaluate the light object's 2D image from a input 2D grid of coordinates and convolve it with a PSF.

eccentric_radii_grid_from

Convert a grid of (y,x) coordinates to an eccentric radius: :math: axis_ratio^0.5 (x^2 + (y^2/q))^0.5

elliptical_radii_grid_from

Convert a grid of (y,x) coordinates to their elliptical radii values: :math: (x^2 + (y^2/q))^0.5

has

Does this instance have an attribute which is of type cls?

image_1d_from

Returns the light profile's 1D image from a grid of Cartesian coordinates, which may have been transformed using the light profile's geometry.

image_2d_from

Returns the Sersic light profile's 2D image from a 2D grid of Cartesian (y,x) coordinates.

image_2d_via_radii_from

Returns the 2D image of the Sersic light profile from a grid of coordinates which are the radial distances of each coordinate from the its centre.

luminosity_integral

Routine to integrate the luminosity of an elliptical light profile.

luminosity_within_circle_from

Integrate the light profile to compute the total luminosity within a circle of specified radius.

padded_image_2d_from

Evaluate the light object's 2D image from a input 2D grid of padded coordinates, where this padding is sufficient to encapsulate all surrounding pixels that will blur light into the original image given the 2D shape of the PSF's kernel.

radial_grid_from

Convert a grid of (y, x) coordinates, to their radial distances from the profile centre (e.g. :math: r = x**2 + y**2).

rotated_grid_from_reference_frame_from

Rotate a grid of (y,x) coordinates which have been transformed to the elliptical reference frame of a profile back to the original unrotated coordinate grid reference frame.

transformed_from_reference_frame_grid_from

Transform a grid of (y,x) coordinates from the reference frame of the profile to the original observer reference frame.

transformed_to_reference_frame_grid_from

Transform a grid of (y,x) coordinates to the reference frame of the profile.

unmasked_blurred_image_2d_from

Evaluate the light object's 2D image from a input 2D grid of coordinates and convolve it with a PSF, using a grid which is not masked.

visibilities_from

Evaluate the light object's 2D image from a input 2D grid of coordinates and transform this to an array of visibilities using a autoarray.operators.transformer.Transformer object and therefore a Fourier Transform.

Attributes

angle

The position angle in degrees of the major-axis of the ellipse defined by profile, defined counter clockwise from the positive x-axis (0.0 > angle > 180.0).

angle_radians

The position angle in radians of the major-axis of the ellipse defined by profile, defined counter clockwise from the positive x-axis (0.0 > angle > 2pi).

axis_ratio

The ratio of the minor-axis to major-axis (b/a) of the ellipse defined by profile (0.0 > q > 1.0).

coefficient_tag

elliptical_effective_radius

The effective_radius of a Sersic light profile is defined as the circular effective radius, which is the radius within which a circular aperture contains half the profile's total integrated light.

half_light_radius

sersic_constant

A parameter derived from Sersic index which ensures that effective radius contains 50% of the profile's total integrated light.