def test_model(data, with_units):
t, y, dy, params = data
# Compute the model using linear regression
A = np.zeros((len(t), 2))
p = params["period"]
dt = np.abs((t-params["transit_time"]+0.5*p) % p-0.5*p)
m_in = dt < 0.5*params["duration"]
A[~m_in, 0] = 1.0
A[m_in, 1] = 1.0
w = np.linalg.solve(np.dot(A.T, A / dy[:, None]**2),
np.dot(A.T, y / dy**2))
model_true = np.dot(A, w)
if with_units:
t = t * u.day
y = y * u.mag
dy = dy * u.mag
model_true = model_true * u.mag
# Compute the model using the periodogram
pgram = BoxLeastSquares(t, y, dy)
model = pgram.model(t, p, params["duration"], params["transit_time"])
# Make sure that the transit mask is consistent with the model
transit_mask = pgram.transit_mask(t, p, params["duration"],
params["transit_time"])
transit_mask0 = (model - model.max()) < 0.0
assert_allclose(transit_mask, transit_mask0)
assert_quantity_allclose(model, model_true)
def test_absolute_times(data, timedelta):
# Make sure that we handle absolute times correctly. We also check that
# TimeDelta works properly when timedelta is True.
# The example data uses relative times
t, y, dy, params = data
# FIXME: There seems to be a numerical stability issue in that if we run
# the algorithm with the same values but offset in time, the transit_time
# is not offset by a fixed amount. To avoid this issue in this test, we
# make sure the first time is also the smallest so that internally the
# values of the relative time should be the same.
t[0] = 0.
# Add units
t = t * u.day
y = y * u.mag
dy = dy * u.mag
# We now construct a set of absolute times but keeping the rest the same.
start = Time('2019-05-04T12:34:56')
trel = TimeDelta(t) if timedelta else t
t = trel + start
# and we set up two instances of BoxLeastSquares, one with absolute and one
# with relative times.
bls1 = BoxLeastSquares(t, y, dy)
bls2 = BoxLeastSquares(trel, y, dy)
results1 = bls1.autopower(0.16 * u.day)
results2 = bls2.autopower(0.16 * u.day)
# All the results should match except transit time which should be
# absolute instead of relative in the first case.
for key in results1:
if key == 'transit_time':
assert_quantity_allclose((results1[key] - start).to(u.day), results2[key])
elif key == 'objective':
assert results1[key] == results2[key]
else:
assert_allclose(results1[key], results2[key])
# Check that model evaluation works fine
model1 = bls1.model(t, 0.2 * u.day, 0.05 * u.day, Time('2019-06-04T12:34:56'))
model2 = bls2.model(trel, 0.2 * u.day, 0.05 * u.day, TimeDelta(1 * u.day))
assert_quantity_allclose(model1, model2)
# Check model validation
with pytest.raises(TypeError) as exc:
bls1.model(t, 0.2 * u.day, 0.05 * u.day, 1 * u.day)
assert exc.value.args[0] == ('transit_time was provided as a relative time '
'but the BoxLeastSquares class was initialized '
'with absolute times.')
with pytest.raises(TypeError) as exc:
bls1.model(trel, 0.2 * u.day, 0.05 * u.day, Time('2019-06-04T12:34:56'))
assert exc.value.args[0] == ('t_model was provided as a relative time '
'but the BoxLeastSquares class was initialized '
'with absolute times.')
with pytest.raises(TypeError) as exc:
bls2.model(trel, 0.2 * u.day, 0.05 * u.day, Time('2019-06-04T12:34:56'))
assert exc.value.args[0] == ('transit_time was provided as an absolute time '
'but the BoxLeastSquares class was initialized '
'with relative times.')
with pytest.raises(TypeError) as exc:
bls2.model(t, 0.2 * u.day, 0.05 * u.day, 1 * u.day)
assert exc.value.args[0] == ('t_model was provided as an absolute time '
'but the BoxLeastSquares class was initialized '
'with relative times.')
# Check compute_stats
stats1 = bls1.compute_stats(0.2 * u.day, 0.05 * u.day, Time('2019-06-04T12:34:56'))
stats2 = bls2.compute_stats(0.2 * u.day, 0.05 * u.day, 1 * u.day)
for key in stats1:
if key == 'transit_times':
assert_quantity_allclose((stats1[key] - start).to(u.day), stats2[key], atol=1e-10 * u.day)
elif key.startswith('depth'):
for value1, value2 in zip(stats1[key], stats2[key]):
assert_quantity_allclose(value1, value2)
else:
assert_allclose(stats1[key], stats2[key])
# Check compute_stats validation
with pytest.raises(TypeError) as exc:
bls1.compute_stats(0.2 * u.day, 0.05 * u.day, 1 * u.day)
assert exc.value.args[0] == ('transit_time was provided as a relative time '
'but the BoxLeastSquares class was initialized '
'with absolute times.')
with pytest.raises(TypeError) as exc:
bls2.compute_stats(0.2 * u.day, 0.05 * u.day, Time('2019-06-04T12:34:56'))
assert exc.value.args[0] == ('transit_time was provided as an absolute time '
'but the BoxLeastSquares class was initialized '
'with relative times.')
# Check transit_mask
mask1 = bls1.transit_mask(t, 0.2 * u.day, 0.05 * u.day, Time('2019-06-04T12:34:56'))
mask2 = bls2.transit_mask(trel, 0.2 * u.day, 0.05 * u.day, 1 * u.day)
assert_equal(mask1, mask2)
# Check transit_mask validation
with pytest.raises(TypeError) as exc:
bls1.transit_mask(t, 0.2 * u.day, 0.05 * u.day, 1 * u.day)
assert exc.value.args[0] == ('transit_time was provided as a relative time '
'but the BoxLeastSquares class was initialized '
'with absolute times.')
with pytest.raises(TypeError) as exc:
bls1.transit_mask(trel, 0.2 * u.day, 0.05 * u.day, Time('2019-06-04T12:34:56'))
assert exc.value.args[0] == ('t was provided as a relative time '
'but the BoxLeastSquares class was initialized '
'with absolute times.')
with pytest.raises(TypeError) as exc:
bls2.transit_mask(trel, 0.2 * u.day, 0.05 * u.day, Time('2019-06-04T12:34:56'))
assert exc.value.args[0] == ('transit_time was provided as an absolute time '
'but the BoxLeastSquares class was initialized '
'with relative times.')
with pytest.raises(TypeError) as exc:
bls2.transit_mask(t, 0.2 * u.day, 0.05 * u.day, 1 * u.day)
assert exc.value.args[0] == ('t was provided as an absolute time '
'but the BoxLeastSquares class was initialized '
'with relative times.')