def test_sky_shell2():
width = 2 * u.deg
rad = 2 * u.deg
model = Shell2SpatialModel(lon_0="1 deg", lat_0="45 deg", r_0=rad + width, eta=0.5)
lon = [1, 2, 4] * u.deg
lat = 45 * u.deg
val = model(lon, lat)
assert val.unit == "deg-2"
desired = [55.979449, 57.831651, 94.919895]
assert_allclose(val.to_value("sr-1"), desired)
radius = model.evaluation_radius
assert radius.unit == "deg"
assert_allclose(radius.value, rad.value + width.value)
assert_allclose(model.r_in.value, rad.value)
assert isinstance(model.to_region(), CircleAnnulusSkyRegion)
Shell2SpatialModel,
SkyModel,
)
tags = [
r"Disk-like, $\eta \rightarrow 0$",
r"Shell, $\eta=0.25$",
r"Peaked, $\eta\rightarrow 1$",
]
eta_range = [0.001, 0.25, 1]
fig, axes = plt.subplots(1, 3, figsize=(9, 6))
for ax, eta, tag in zip(axes, eta_range, tags):
model = Shell2SpatialModel(
lon_0="10 deg",
lat_0="20 deg",
r_0="2 deg",
eta=eta,
frame="galactic",
)
model.plot(ax=ax)
ax.set_title(tag)
ax.set_xticks([])
ax.set_yticks([])
plt.tight_layout()
# %%
# YAML representation
# -------------------
# Here is an example YAML file using the model:
pwl = PowerLawSpectralModel()