adding changelog, fixing test

docs/changes/2641.feature.rst

@@ -0,0 +1,4 @@
+Adds ``ctapipe.image.psf_model`` with the parent class for psf models called ``PSFModel`` and a psf model based on pure coma abbaration called ``ComaModel``
+- All psf models have a function ``PSFModel.update_location`` that updates the location in the focal plane where the PSF is evaluated from
+- The function ``PSFModel.update_model_parameters`` allows to update the parameters of the PSF model
+- The function ``PSFModel.pdf`` gives the value of the PSF in a given location

src/ctapipe/image/psf_model.py

@@ -90,7 +90,7 @@ def __init__(
             Parameters describing the dependency of the asymmetry of the psf on the distance to the center of the camera
         radial_scale_params : list
             Parameters describing the dependency of the radial scale on the distance to the center of the camera
-        radial_scale_params : list
+        az_scale_params : list
             Parameters describing the dependency of the azimuthal scale scale on the distance to the center of the camera
         """
 
@@ -126,7 +126,7 @@ def pdf(self, r, f):
 
         Parameters
         ----------
-         r : float
+        r : float
             distance to the center of the camera in meters
         f : float
             polar angle in radians

src/ctapipe/image/tests/test_psf_model.py

@@ -24,4 +24,4 @@ def test_psf():
 def test_asymptotic_behavior():
     psf_coma = PSFModel.from_name("ComaModel")
     psf_coma.update_location(1.0, 0.0)
-    assert np.isclose(psf_coma.psf(10.0, 0.0), 0.0)
+    assert np.isclose(psf_coma.pdf(10.0, 0.0), 0.0)