possible fix for the failing tests and removal of unnecessary object

src/simweights/__init__.py

@@ -18,7 +18,6 @@
     "CircleInjector",
     "CorsikaWeighter",
     "NaturalRateCylinder",
-    "IceTopNaturalRateCylinder",
     "UniformSolidAngleCylinder",
     "TIG1996",
     "FixedFractionFlux",
@@ -64,11 +63,6 @@
 from ._nugen_weighter import NuGenWeighter
 from ._pdgcode import PDGCode
 from ._powerlaw import PowerLaw
-from ._spatial import (
-    CircleInjector,
-    IceTopNaturalRateCylinder,
-    NaturalRateCylinder,
-    UniformSolidAngleCylinder,
-)
+from ._spatial import CircleInjector, NaturalRateCylinder, UniformSolidAngleCylinder
 from ._utils import corsika_to_pdg
 from ._weighter import Weighter

src/simweights/_icetop_weighter.py

@@ -9,7 +9,7 @@
 
 from ._generation_surface import GenerationSurface, generation_surface
 from ._powerlaw import PowerLaw
-from ._spatial import IceTopNaturalRateCylinder
+from ._spatial import NaturalRateCylinder
 from ._utils import get_column, get_table
 from ._weighter import Weighter
 
@@ -25,7 +25,7 @@ def sframe_icetop_surface(table: Any) -> GenerationSurface:
             get_column(table, "min_energy")[i],
             get_column(table, "max_energy")[i],
         )
-        spatial = IceTopNaturalRateCylinder(
+        spatial = NaturalRateCylinder(
             0,  # set cylinder height to 0 to get simple surface plane
             get_column(table, "sampling_radius")[i],
             np.cos(get_column(table, "max_zenith")[i]),

src/simweights/_spatial.py

@@ -126,29 +126,6 @@ def pdf(self, cos_zen: ArrayLike) -> NDArray[np.float64]:
         )
 
 
-class IceTopNaturalRateCylinder(CylinderBase):
-    r"""Angular distribution when zenith distribution matched the natural rate of an isotropic source.
-
-    For a given zenith angle the intensity of particles thrown was proportional to the cross-sectional area
-    perpendicular to the direction of the particle.
-    """
-
-    def __init__(self, length: float, radius: float, cos_zen_min: float, cos_zen_max: float) -> None:
-        super().__init__(length, radius, cos_zen_min, cos_zen_max)
-        self.etendue = (
-            2 * np.pi * (self.cos_zen_max - self.cos_zen_min) * self._cap
-        )  # This is needed to make the tests work
-        self._normalization = 1 / self.etendue
-
-    def pdf(self, cos_zen: ArrayLike) -> NDArray[np.float64]:
-        cosz = np.asfarray(cos_zen)
-        return np.piecewise(
-            cosz,
-            [(cosz >= self.cos_zen_min) & (cosz <= self.cos_zen_max)],
-            [self._normalization],
-        )
-
-
 class CircleInjector:
     """Particles are generated on a circle perpendicular to the direction of the particle.
 

tests/test_icetop_datasets.py

@@ -31,7 +31,7 @@ def cmp_dataset(self, fname):
         assert len(reffile["I3TopInjectorInfo"]) == 1
         si = reffile["I3TopInjectorInfo"][0]
         pri = reffile["MCPrimary"]
-        solid_angle = 2 * np.pi * (np.cos(si["min_zenith"]) - np.cos(si["max_zenith"]))
+        solid_angle = np.pi * (np.cos(si["min_zenith"]) ** 2 - np.cos(si["max_zenith"]) ** 2)
         injection_area = np.pi * (si["sampling_radius"] * 1e2) ** 2
         energy_integral = np.log(si["max_energy"] / si["min_energy"])  # assuming E^-1
         energy_factor = energy_integral * pri["energy"]

tests/test_icetop_weighter.py

@@ -27,7 +27,7 @@ class TestIceTopWeighter(unittest.TestCase):
     def test_icetop_corsika(self):
         nevents = 10000
         pdgid = 12
-        c1 = simweights.IceTopNaturalRateCylinder(0, 300, 0, 1)
+        c1 = simweights.NaturalRateCylinder(0, 300, 0, 1)
         p1 = simweights.PowerLaw(0, 1e3, 1e4)
 
         weight = np.zeros(nevents, dtype=particle_dtype)