commit new changes

Author: samlange04

autogalaxy/__init__.py

@@ -62,6 +62,7 @@
 from .ellipse.dataset_interp import DatasetInterp
 from .ellipse.ellipse.ellipse import Ellipse
 from .ellipse.ellipse.ellipse_multipole import EllipseMultipole
+from .ellipse.ellipse.ellipse_multipole import EllipseMultipoleRelative
 from .ellipse.fit_ellipse import FitEllipse
 from .ellipse.model.analysis import AnalysisEllipse
 from .operate.image import OperateImage

autogalaxy/ellipse/ellipse/ellipse_multipole.py

@@ -1,5 +1,6 @@
 import numpy as np
 from typing import Tuple
+from autogalaxy.convert import multipole_k_m_and_phi_m_from, multipole_comps_from
 
 
 from autogalaxy.ellipse.ellipse.ellipse import Ellipse
@@ -12,7 +13,7 @@ def __init__(
         multipole_comps: Tuple[float, float] = (0.0, 0.0),
     ):
         """
-        class representing the multipole of an ellispe with, which is used to perform ellipse fitting to
+        class representing the multipole of an ellipse with, which is used to perform ellipse fitting to
         2D data (e.g. an image).
 
         The multipole is added to the (y,x) coordinates of an ellipse that are already computed via the `Ellipse` class.
@@ -68,3 +69,54 @@ def points_perturbed_from(
         y = points[:, 0] + (radial * np.sin(angles))
 
         return np.stack(arrays=(y, x), axis=-1)
+
+
+class EllipseMultipoleRelative(EllipseMultipole):
+    def __init__(
+        self,
+        m=4,
+        input_multipole_comps: Tuple[float, float] = (0.0, 0.0),
+        major_axis=1.,
+    ):
+
+        k, phi = multipole_k_m_and_phi_m_from(multipole_comps=input_multipole_comps, m=m)
+        k_adjusted = k*major_axis
+
+        adjusted_multipole_comps = multipole_comps_from(k_adjusted, phi, m)
+
+        super().__init__(m, adjusted_multipole_comps)
+
+        self.adjusted_multipole_comps = adjusted_multipole_comps
+        self.m = m
+
+    def points_perturbed_from(
+        self, pixel_scale, points, ellipse: Ellipse
+    ) -> np.ndarray:
+        """
+        Returns the (y,x) coordinates of the input points, which are perturbed by the multipole of the ellipse.
+
+        Parameters
+        ----------
+        pixel_scale
+            The pixel scale of the data that the ellipse is fitted to and interpolated over.
+        points
+            The (y,x) coordinates of the ellipse that are perturbed by the multipole.
+        ellipse
+            The ellipse that is perturbed by the multipole, which is used to compute the angles of the ellipse.
+
+        Returns
+        -------
+        The (y,x) coordinates of the input points, which are perturbed by the multipole.
+        """
+
+        angles = ellipse.angles_from_x0_from(pixel_scale=pixel_scale)
+
+        radial = np.add(
+            self.adjusted_multipole_comps[1] * np.cos(self.m * (angles - ellipse.angle_radians)),
+            self.adjusted_multipole_comps[0] * np.sin(self.m * (angles - ellipse.angle_radians)),
+        )
+
+        x = points[:, 1] + (radial * np.cos(angles))
+        y = points[:, 0] + (radial * np.sin(angles))
+
+        return np.stack(arrays=(y, x), axis=-1)

autogalaxy/ellipse/fit_ellipse.py

@@ -328,4 +328,4 @@ def figure_of_merit(self) -> float:
         -------
         The figure of merit of the fit.
         """
-        return self.log_likelihood
+        return -0.5* (self.chi_squared + self.noise_normalization)