Source code for autogalaxy.profiles.geometry_profiles

from typing import Optional, Tuple, Type

import numpy as np

import autoarray as aa
from autoarray.structures.grids.transformed_2d import Grid2DTransformedNumpy
from autogalaxy import convert


class GeometryProfile:
    """
    An abstract geometry profile, which describes profiles with y and x centre Cartesian coordinates

    Parameters
    ----------
    centre
        The (y,x) arc-second coordinates of the profile centre.
    """

    def __init__(self, centre: Tuple[float, float] = (0.0, 0.0)):
        self.centre = centre

    def __hash__(self):
        return id(self)

    def __repr__(self):
        return "{}\n{}".format(
            self.__class__.__name__,
            "\n".join(["{}: {}".format(k, v) for k, v in self.__dict__.items()]),
        )

    def __eq__(self, other):
        return self.__dict__ == other.__dict__

    def has(self, cls: Type) -> bool:
        """
        Does this instance have an attribute which is of type cls?
        """
        return aa.util.misc.has(values=self.__dict__.values(), cls=cls)

    def transformed_to_reference_frame_grid_from(self, grid):
        raise NotImplemented()

    def transformed_from_reference_frame_grid_from(self, grid):
        raise NotImplemented()

    def _radial_projected_shape_slim_from(self, grid: aa.type.Grid1D2DLike) -> int:
        """
        To make 1D plots (e.g. `image_1d_from()`) from an input 2D grid, one uses that 2D grid to radially project
        the coordinates across the profile's major-axis.

        This function computes the distance from the profile centre to the edge of this 2D grid.

        If a 1D grid is input it returns the shape of this grid, as the grid itself defines the radial coordinates.

        Parameters
        ----------
        grid
            A 1D or 2D grid from which a 1D plot of the profile is to be created.
        """

        if isinstance(grid, aa.Grid1D):
            return grid.sub_shape_slim
        elif isinstance(grid, aa.Grid2DIrregular):
            return grid.slim.shape[0]

        return grid.grid_2d_radial_projected_shape_slim_from(centre=self.centre)


[docs]class SphProfile(GeometryProfile): """ A spherical profile, which describes profiles with y and x centre Cartesian coordinates. Parameters ---------- centre The (y,x) arc-second coordinates of the profile centre. """ def __init__(self, centre: Tuple[float, float] = (0.0, 0.0)): super().__init__(centre=centre)
[docs] @aa.grid_dec.grid_2d_to_structure @aa.grid_dec.transform def radial_grid_from(self, grid: aa.type.Grid2DLike) -> np.ndarray: """ Convert a grid of (y, x) coordinates, to their radial distances from the profile centre (e.g. :math: r = x**2 + y**2). Parameters ---------- grid The grid of (y, x) coordinates which are converted to radial distances. """ return np.sqrt(np.add(np.square(grid[:, 0]), np.square(grid[:, 1])))
[docs] def angle_to_profile_grid_from( self, grid_angles: np.ndarray ) -> Tuple[np.ndarray, np.ndarray]: """ Convert a grid of angles, defined in degrees counter-clockwise from the positive x-axis, to a grid of angles between the input angles and the profile. Parameters ---------- grid_angles The angle theta counter-clockwise from the positive x-axis to each coordinate in radians. """ return np.cos(grid_angles), np.sin(grid_angles)
@aa.grid_dec.grid_2d_to_structure def _cartesian_grid_via_radial_from( self, grid: aa.type.Grid2DLike, radius: np.ndarray ) -> aa.type.Grid2DLike: """ Convert a grid of (y,x) coordinates with their specified radial distances (e.g. :math: r = x**2 + y**2) to their original (y,x) Cartesian coordinates. Parameters ---------- grid The (y, x) coordinates already translated to the reference frame of the profile. radius The circular radius of each coordinate from the profile center. """ grid_angles = np.arctan2(grid[:, 0], grid[:, 1]) cos_theta, sin_theta = self.angle_to_profile_grid_from(grid_angles=grid_angles) return np.multiply(radius[:, None], np.vstack((sin_theta, cos_theta)).T)
[docs] @aa.grid_dec.grid_2d_to_structure def transformed_to_reference_frame_grid_from(self, grid): """ Transform a grid of (y,x) coordinates to the reference frame of the profile. This performs a translation to the profile's `centre`. Parameters ---------- grid The (y, x) coordinates in the original reference frame of the grid. """ transformed = np.subtract(grid, self.centre) return Grid2DTransformedNumpy(values=transformed)
[docs] @aa.grid_dec.grid_2d_to_structure def transformed_from_reference_frame_grid_from(self, grid): """ Transform a grid of (y,x) coordinates from the reference frame of the profile to the original observer reference frame. This performs a translation from the profile's `centre`. Parameters ---------- grid The (y, x) coordinates in the reference frame of the profile. """ transformed = np.add(grid, self.centre) return Grid2DTransformedNumpy(values=np.array(transformed))
[docs]class EllProfile(SphProfile): def __init__( self, centre: Tuple[float, float] = (0.0, 0.0), ell_comps: Tuple[float, float] = (0.0, 0.0), ): """ An elliptical profile, which describes the geometry of profiles defined by an ellipse. The elliptical components (`ell_comps`) of this profile are used to define the `axis_ratio` (q) and `angle` (\phi) : :math: \phi = (180/\pi) * arctan2(e_y / e_x) / 2 :math: f = sqrt(e_y^2 + e_x^2) :math: q = (1 - f) / (1 + f) Where: e_y = y elliptical component = `ell_comps[0]` e_x = x elliptical component = `ell_comps[1]` q = axis_ratio (major_axis / minor_axis) This means that given an axis-ratio and angle the elliptical components can be computed as: :math: f = (1 - q) / (1 + q) :math: e_y = f * sin(2*\phi) :math: e_x = f * cos(2*\phi) For an input (y,x) grid of Cartesian coordinates this is used to compute the elliptical coordinates of a profile: .. math:: \\xi = q^{0.5} * ((y-y_c^2 + x-x_c^2 / q^2)^{0.5} Where: y_c = profile y centre = `centre[0]` x_c = profile x centre = `centre[1]` The majority of elliptical profiles use \\xi to compute their image. Parameters ---------- centre The (y,x) arc-second coordinates of the profile centre. ell_comps The first and second elliptical components of the profile. """ super().__init__(centre=centre) self.ell_comps = ell_comps @property def axis_ratio(self) -> float: """ The ratio of the minor-axis to major-axis (b/a) of the ellipse defined by profile (0.0 > q > 1.0). """ return convert.axis_ratio_from(ell_comps=self.ell_comps) @property def angle(self) -> float: """ 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). """ return convert.angle_from(ell_comps=self.ell_comps) @property def angle_radians(self) -> float: """ 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). """ return np.radians(self.angle) @property def _cos_angle(self) -> float: return self._cos_and_sin_to_x_axis()[0] @property def _sin_angle(self) -> float: return self._cos_and_sin_to_x_axis()[1] def _cos_and_sin_to_x_axis(self): """ Determine the sin and cosine of the angle between the profile's ellipse and the positive x-axis, counter-clockwise. """ angle_radians = np.radians(self.angle) return np.cos(angle_radians), np.sin(angle_radians)
[docs] def angle_to_profile_grid_from(self, grid_angles): """ The angle between each angle theta on the grid and the profile, in radians. Parameters ---------- grid_angles The angle theta counter-clockwise from the positive x-axis to each coordinate in radians. """ theta_coordinate_to_profile = np.add(grid_angles, -self.angle_radians) return np.cos(theta_coordinate_to_profile), np.sin(theta_coordinate_to_profile)
[docs] @aa.grid_dec.grid_2d_to_structure def rotated_grid_from_reference_frame_from( self, grid, angle: Optional[float] = None ): """ 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. Note that unlike the method `transformed_from_reference_frame_grid_from` the coordinates are not translated back to the profile's original centre. This routine is used after computing deflection angles in the reference frame of the profile, so that the deflection angles can be re-rotated to the frame of the original coordinates before performing ray-tracing. Parameters ---------- grid The (y, x) coordinates in the reference frame of an elliptical profile. angle Manually input an angle which is used instead of the profile's `angle` attribute. This is used in certain circumstances where the angle applied is different to the profile's `angle` attribute, for example weak lensing rotations which are typically twice that profile's `angle` attribute. """ if angle is None: angle = self.angle return aa.util.geometry.transform_grid_2d_from_reference_frame( grid_2d=grid, centre=(0.0, 0.0), angle=angle )
[docs] @aa.grid_dec.grid_2d_to_structure @aa.grid_dec.transform @aa.grid_dec.relocate_to_radial_minimum def elliptical_radii_grid_from(self, grid: aa.type.Grid2DLike) -> np.ndarray: """ Convert a grid of (y,x) coordinates to their elliptical radii values: :math: (x^2 + (y^2/q))^0.5 If the coordinates have not been transformed to the profile's geometry (e.g. translated to the profile `centre`), this is performed automatically. Parameters ---------- grid The (y, x) coordinates in the reference frame of the elliptical profile. """ return np.sqrt( np.add( np.square(grid[:, 1]), np.square(np.divide(grid[:, 0], self.axis_ratio)) ) )
[docs] @aa.grid_dec.grid_2d_to_structure @aa.grid_dec.transform @aa.grid_dec.relocate_to_radial_minimum def eccentric_radii_grid_from(self, grid: aa.type.Grid2DLike) -> np.ndarray: """ Convert a grid of (y,x) coordinates to an eccentric radius: :math: axis_ratio^0.5 (x^2 + (y^2/q))^0.5 This is used in certain light profiles define their half-light radii as a circular radius. If the coordinates have not been transformed to the profile's geometry (e.g. translated to the profile `centre`), this is performed automatically. Parameters ---------- grid The (y, x) coordinates in the reference frame of the elliptical profile. """ return np.multiply( np.sqrt(self.axis_ratio), self.elliptical_radii_grid_from(grid) ).view(np.ndarray)
[docs] @aa.grid_dec.grid_2d_to_structure def transformed_to_reference_frame_grid_from( self, grid: aa.type.Grid2DLike ) -> Grid2DTransformedNumpy: """ Transform a grid of (y,x) coordinates to the reference frame of the profile. This includes a translation to the profile's `centre` and a rotation using its `angle`. Parameters ---------- grid The (y, x) coordinates in the original reference frame of the grid. """ if self.__class__.__name__.endswith("Sph"): return super().transformed_to_reference_frame_grid_from( grid=Grid2DTransformedNumpy(values=grid) ) transformed = aa.util.geometry.transform_grid_2d_to_reference_frame( grid_2d=grid, centre=self.centre, angle=self.angle ) return Grid2DTransformedNumpy(values=transformed)
[docs] @aa.grid_dec.grid_2d_to_structure def transformed_from_reference_frame_grid_from( self, grid: aa.type.Grid2DLike ) -> aa.type.Grid2DLike: """ Transform a grid of (y,x) coordinates from the reference frame of the profile to the original observer reference frame. This includes a translation from the profile's `centre` and a rotation using its `angle`. Parameters ---------- grid The (y, x) coordinates in the reference frame of the profile. """ if self.__class__.__name__.startswith("Sph"): return super().transformed_from_reference_frame_grid_from( grid=Grid2DTransformedNumpy(values=grid) ) return aa.util.geometry.transform_grid_2d_from_reference_frame( grid_2d=grid, centre=self.centre, angle=self.angle )
def _eta_u(self, u, coordinates): return np.sqrt( ( u * ( (coordinates[1] ** 2) + (coordinates[0] ** 2 / (1 - (1 - self.axis_ratio**2) * u)) ) ) )