def test_observation_s2n(image_data):
obs = Observation(image=image_data['image'], weight=image_data['weight'])
s2n = obs.get_s2n()
s2n_true = (np.sum(image_data['image']) /
np.sqrt(np.sum(1.0 / image_data['weight'])))
assert np.allclose(s2n, s2n_true)
def test_observation_s2n(image_data):
obs = Observation(image=image_data['image'], weight=image_data['weight'])
s2n = obs.get_s2n()
s2n_true = (np.sum(image_data['image']) /
np.sqrt(np.sum(1.0 / image_data['weight'])))
assert np.allclose(s2n, s2n_true)
# if we are not storing pixels, when we can have an all zero weight map
# in this case s2n is -9999
obs = Observation(
image=image_data['image'],
weight=np.zeros_like(obs.weight),
store_pixels=False,
)
assert np.allclose(obs.get_s2n(), -9999)
