def test_fold():
times = Time([1, 2, 3, 8, 9, 12], format='unix')
ts = TimeSeries(time=times)
ts['flux'] = [1, 4, 4, 3, 2, 3]
# Try without midpoint epoch, as it should default to the first time
tsf = ts.fold(period=3 * u.s)
assert isinstance(tsf.time, TimeDelta)
assert_allclose(tsf.time.sec, [0, 1, -1, 1, -1, -1], rtol=1e-6)
# Try with midpoint epoch
tsf = ts.fold(period=4 * u.s, midpoint_epoch=Time(2.5, format='unix'))
assert isinstance(tsf.time, TimeDelta)
assert_allclose(tsf.time.sec, [-1.5, -0.5, 0.5, 1.5, -1.5, 1.5], rtol=1e-6)
def test_fold_invalid_options():
times = Time([1, 2, 3, 8, 9, 12], format='unix')
ts = TimeSeries(time=times)
ts['flux'] = [1, 4, 4, 3, 2, 3]
with pytest.raises(u.UnitsError,
match='period should be a Quantity in units of time'):
ts.fold(period=3.2)
with pytest.raises(u.UnitsError,
match='period should be a Quantity in units of time'):
ts.fold(period=3.2 * u.m)
with pytest.raises(u.UnitsError,
match='epoch_phase should be a Quantity in units of '
'time when normalize_phase=False'):
ts.fold(period=3.2 * u.s, epoch_phase=0.2)
with pytest.raises(u.UnitsError,
match='epoch_phase should be a dimensionless Quantity '
'or a float when normalize_phase=True'):
ts.fold(period=3.2 * u.s, epoch_phase=0.2 * u.s, normalize_phase=True)
with pytest.raises(u.UnitsError,
match='wrap_phase should be a Quantity in units of '
'time when normalize_phase=False'):
ts.fold(period=3.2 * u.s, wrap_phase=0.2)
with pytest.raises(u.UnitsError,
match='wrap_phase should be dimensionless when '
'normalize_phase=True'):
ts.fold(period=3.2 * u.s, wrap_phase=0.2 * u.s, normalize_phase=True)
with pytest.raises(ValueError,
match='wrap_phase should be between 0 and the period'):
ts.fold(period=3.2 * u.s, wrap_phase=-0.1 * u.s)
with pytest.raises(ValueError,
match='wrap_phase should be between 0 and the period'):
ts.fold(period=3.2 * u.s, wrap_phase=-4.2 * u.s)
with pytest.raises(ValueError,
match='wrap_phase should be between 0 and 1'):
ts.fold(period=3.2 * u.s, wrap_phase=-0.1, normalize_phase=True)
with pytest.raises(ValueError,
match='wrap_phase should be between 0 and 1'):
ts.fold(period=3.2 * u.s, wrap_phase=2.2, normalize_phase=True)
def test_fold():
times = Time([1, 2, 3, 8, 9, 12], format='unix')
ts = TimeSeries(time=times)
ts['flux'] = [1, 4, 4, 3, 2, 3]
# Try without epoch time, as it should default to the first time and
# wrapping at half the period.
tsf = ts.fold(period=3.2 * u.s)
assert isinstance(tsf.time, TimeDelta)
assert_allclose(tsf.time.sec, [0, 1, -1.2, 0.6, -1.6, 1.4], rtol=1e-6)
# Try with epoch time
tsf = ts.fold(period=3.2 * u.s, epoch_time=Time(1.6, format='unix'))
assert isinstance(tsf.time, TimeDelta)
assert_allclose(tsf.time.sec, [-0.6, 0.4, 1.4, 0.0, 1.0, 0.8], rtol=1e-6, atol=1e-6)
# Now with wrap_phase set to the full period
tsf = ts.fold(period=3.2 * u.s, wrap_phase=3.2 * u.s)
assert isinstance(tsf.time, TimeDelta)
assert_allclose(tsf.time.sec, [0, 1, 2, 0.6, 1.6, 1.4], rtol=1e-6)
# Now set epoch_phase to be 1/4 of the way through the phase
tsf = ts.fold(period=3.2 * u.s, epoch_phase=0.8 * u.s)
assert isinstance(tsf.time, TimeDelta)
assert_allclose(tsf.time.sec, [0.8, -1.4, -0.4, 1.4, -0.8, -1.0], rtol=1e-6)
# And combining epoch_phase and wrap_phase
tsf = ts.fold(period=3.2 * u.s, epoch_phase=0.8 * u.s, wrap_phase=3.2 * u.s)
assert isinstance(tsf.time, TimeDelta)
assert_allclose(tsf.time.sec, [0.8, 1.8, 2.8, 1.4, 2.4, 2.2], rtol=1e-6)
# Now repeat the above tests but with normalization applied
# Try without epoch time, as it should default to the first time and
# wrapping at half the period.
tsf = ts.fold(period=3.2 * u.s, normalize_phase=True)
assert isinstance(tsf.time, Quantity)
assert_allclose(tsf.time.to_value(u.one),
[0, 1/3.2, -1.2/3.2, 0.6/3.2, -1.6/3.2, 1.4/3.2],
rtol=1e-6)
# Try with epoch time
tsf = ts.fold(period=3.2 * u.s, epoch_time=Time(1.6, format='unix'),
normalize_phase=True)
assert isinstance(tsf.time, Quantity)
assert_allclose(tsf.time.to_value(u.one),
[-0.6/3.2, 0.4/3.2, 1.4/3.2, 0.0/3.2, 1.0/3.2, 0.8/3.2],
rtol=1e-6, atol=1e-6)
# Now with wrap_phase set to the full period
tsf = ts.fold(period=3.2 * u.s, wrap_phase=1, normalize_phase=True)
assert isinstance(tsf.time, Quantity)
assert_allclose(tsf.time.to_value(u.one),
[0, 1/3.2, 2/3.2, 0.6/3.2, 1.6/3.2, 1.4/3.2],
rtol=1e-6)
# Now set epoch_phase to be 1/4 of the way through the phase
tsf = ts.fold(period=3.2 * u.s, epoch_phase=0.25, normalize_phase=True)
assert isinstance(tsf.time, Quantity)
assert_allclose(tsf.time.to_value(u.one),
[0.8/3.2, -1.4/3.2, -0.4/3.2, 1.4/3.2, -0.8/3.2, -1.0/3.2],
rtol=1e-6)
# And combining epoch_phase and wrap_phase
tsf = ts.fold(period=3.2 * u.s, epoch_phase=0.25, wrap_phase=1,
normalize_phase=True)
assert isinstance(tsf.time, Quantity)
assert_allclose(tsf.time.to_value(u.one),
[0.8/3.2, 1.8/3.2, 2.8/3.2, 1.4/3.2, 2.4/3.2, 2.2/3.2],
rtol=1e-6)
