Exemple #1
0
def test_model_units_match(data, t_unit, frequency_unit, y_unit):
    t, y, dy = data
    t_fit = t[:5]
    frequency = 1.0

    t = t * t_unit
    t_fit = t_fit * t_unit
    y = y * y_unit
    dy = dy * y_unit
    frequency = frequency * frequency_unit

    ls = LombScargle(t, y, dy)
    y_fit = ls.model(t_fit, frequency)
    assert y_fit.unit == y_unit
def test_model_units_match(data, t_unit, frequency_unit, y_unit):
    t, y, dy = data
    t_fit = t[:5]
    frequency = 1.0

    t = t * t_unit
    t_fit = t_fit * t_unit
    y = y * y_unit
    dy = dy * y_unit
    frequency = frequency * frequency_unit

    ls = LombScargle(t, y, dy)
    y_fit = ls.model(t_fit, frequency)
    assert y_fit.unit == y_unit
def test_model(fit_mean, with_units, freq):
    rand = np.random.RandomState(0)
    t = 10 * rand.rand(40)
    params = 10 * rand.rand(3)

    y = np.zeros_like(t)
    if fit_mean:
        y += params[0]
    y += params[1] * np.sin(2 * np.pi * freq * (t - params[2]))

    if with_units:
        t = t * units.day
        y = y * units.mag
        freq = freq / units.day

    ls = LombScargle(t, y, center_data=False, fit_mean=fit_mean)
    y_fit = ls.model(t, freq)
    assert_quantity_allclose(y_fit, y)
Exemple #4
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def test_model(fit_mean, with_units, freq):
    rand = np.random.RandomState(0)
    t = 10 * rand.rand(40)
    params = 10 * rand.rand(3)

    y = np.zeros_like(t)
    if fit_mean:
        y += params[0]
    y += params[1] * np.sin(2 * np.pi * freq * (t - params[2]))

    if with_units:
        t = t * u.day
        y = y * u.mag
        freq = freq / u.day

    ls = LombScargle(t, y, center_data=False, fit_mean=fit_mean)
    y_fit = ls.model(t, freq)
    assert_quantity_allclose(y_fit, y)
def test_model_parameters(data, nterms, fit_mean, center_data, errors,
                          with_units):
    if nterms == 0 and not fit_mean:
        return

    t, y, dy = data
    frequency = 1.5
    if with_units:
        t = t * units.day
        y = y * units.mag
        dy = dy * units.mag
        frequency = frequency / t.unit

    if errors == 'none':
        dy = None
    elif errors == 'partial':
        dy = dy[0]
    elif errors == 'full':
        pass
    else:
        raise ValueError("Unrecognized error type: '{0}'".format(errors))

    ls = LombScargle(t,
                     y,
                     dy,
                     nterms=nterms,
                     fit_mean=fit_mean,
                     center_data=center_data)
    tfit = np.linspace(0, 20, 10)
    if with_units:
        tfit = tfit * units.day

    model = ls.model(tfit, frequency)
    params = ls.model_parameters(frequency)
    design = ls.design_matrix(frequency, t=tfit)
    offset = ls.offset()

    assert len(params) == int(fit_mean) + 2 * nterms

    assert_quantity_allclose(offset + design.dot(params), model)
Exemple #6
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def test_model_parameters(data, nterms, fit_mean, center_data,
                          errors, with_units):
    if nterms == 0 and not fit_mean:
        return

    t, y, dy = data
    frequency = 1.5
    if with_units:
        t = t * u.day
        y = y * u.mag
        dy = dy * u.mag
        frequency = frequency / t.unit

    if errors == 'none':
        dy = None
    elif errors == 'partial':
        dy = dy[0]
    elif errors == 'full':
        pass
    else:
        raise ValueError("Unrecognized error type: '{0}'".format(errors))

    ls = LombScargle(t, y, dy,
                     nterms=nterms,
                     fit_mean=fit_mean,
                     center_data=center_data)
    tfit = np.linspace(0, 20, 10)
    if with_units:
        tfit = tfit * u.day

    model = ls.model(tfit, frequency)
    params = ls.model_parameters(frequency)
    design = ls.design_matrix(frequency, t=tfit)
    offset = ls.offset()

    assert len(params) == int(fit_mean) + 2 * nterms

    assert_quantity_allclose(offset + design.dot(params), model)
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 = 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 LombScargle, one with absolute and one
    # with relative times.
    ls1 = LombScargle(t, y, dy)
    ls2 = LombScargle(trel, y, dy)

    kwargs = dict(samples_per_peak=6,
                  nyquist_factor=2,
                  minimum_frequency=2 / u.day,
                  maximum_frequency=None)

    freq1 = ls1.autofrequency(**kwargs)
    freq2 = ls2.autofrequency(**kwargs)
    assert_quantity_allclose(freq1, freq2)

    power1 = ls1.power(freq1)
    power2 = ls2.power(freq2)
    assert_quantity_allclose(power1, power2)

    freq1, power1 = ls1.autopower(**kwargs)
    freq2, power2 = ls2.autopower(**kwargs)
    assert_quantity_allclose(freq1, freq2)
    assert_quantity_allclose(power1, power2)

    model1 = ls1.model(t, 2 / u.day)
    model2 = ls2.model(trel, 2 / u.day)
    assert_quantity_allclose(model1, model2)

    # Check model validation

    with pytest.raises(TypeError) as exc:
        ls1.model(trel, 2 / u.day)
    assert exc.value.args[0] == ('t was provided as a relative time but the '
                                 'LombScargle class was initialized with '
                                 'absolute times.')

    with pytest.raises(TypeError) as exc:
        ls2.model(t, 2 / u.day)
    assert exc.value.args[0] == ('t was provided as an absolute time but the '
                                 'LombScargle class was initialized with '
                                 'relative times.')

    # Check design matrix

    design1 = ls1.design_matrix(2 / u.day, t=t)
    design2 = ls2.design_matrix(2 / u.day, t=trel)
    assert_quantity_allclose(design1, design2)

    # Check design matrix validation

    with pytest.raises(TypeError) as exc:
        ls1.design_matrix(2 / u.day, t=trel)
    assert exc.value.args[0] == ('t was provided as a relative time but the '
                                 'LombScargle class was initialized with '
                                 'absolute times.')

    with pytest.raises(TypeError) as exc:
        ls2.design_matrix(2 / u.day, t=t)
    assert exc.value.args[0] == ('t was provided as an absolute time but the '
                                 'LombScargle class was initialized with '
                                 'relative times.')
Exemple #8
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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 = 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 LombScargle, one with absolute and one
    # with relative times.
    ls1 = LombScargle(t, y, dy)
    ls2 = LombScargle(trel, y, dy)

    kwargs = dict(samples_per_peak=6, nyquist_factor=2,
                  minimum_frequency=2 / u.day, maximum_frequency=None)

    freq1 = ls1.autofrequency(**kwargs)
    freq2 = ls2.autofrequency(**kwargs)
    assert_quantity_allclose(freq1, freq2)

    power1 = ls1.power(freq1)
    power2 = ls2.power(freq2)
    assert_quantity_allclose(power1, power2)

    freq1, power1 = ls1.autopower(**kwargs)
    freq2, power2 = ls2.autopower(**kwargs)
    assert_quantity_allclose(freq1, freq2)
    assert_quantity_allclose(power1, power2)

    model1 = ls1.model(t, 2 / u.day)
    model2 = ls2.model(trel, 2 / u.day)
    assert_quantity_allclose(model1, model2)

    # Check model validation

    with pytest.raises(TypeError) as exc:
        ls1.model(trel, 2 / u.day)
    assert exc.value.args[0] == ('t was provided as a relative time but the '
                                 'LombScargle class was initialized with '
                                 'absolute times.')

    with pytest.raises(TypeError) as exc:
        ls2.model(t, 2 / u.day)
    assert exc.value.args[0] == ('t was provided as an absolute time but the '
                                 'LombScargle class was initialized with '
                                 'relative times.')

    # Check design matrix

    design1 = ls1.design_matrix(2 / u.day, t=t)
    design2 = ls2.design_matrix(2 / u.day, t=trel)
    assert_quantity_allclose(design1, design2)

    # Check design matrix validation

    with pytest.raises(TypeError) as exc:
        ls1.design_matrix(2 / u.day, t=trel)
    assert exc.value.args[0] == ('t was provided as a relative time but the '
                                 'LombScargle class was initialized with '
                                 'absolute times.')

    with pytest.raises(TypeError) as exc:
        ls2.design_matrix(2 / u.day, t=t)
    assert exc.value.args[0] == ('t was provided as an absolute time but the '
                                 'LombScargle class was initialized with '
                                 'relative times.')