def test_snr_constant_wav_ref_outside_wav(wav_ref):
"""Wav-ref outside bounds of wav should raise ValueError"""
wav = np.linspace(1, 3, 60)
flux = np.random.randn(len(wav))
with pytest.raises(ValueError):
snrnorm.snr_constant_wav(wav, flux, wav_ref)
def test_band_snr_norm(testing_spectrum, sampling):
"""Compared to wav snr norm."""
wav, flux = testing_spectrum
wav, flux = convolve_and_resample(
wav, flux, vsini=1, R=100000, band="J", sampling=sampling
)
assert snrnorm.snr_constant_band(
wav, flux, band="J", snr=100, sampling=sampling
) == snrnorm.snr_constant_wav(wav, flux, wav_ref=1.25, snr=100, sampling=sampling)
assert snrnorm.snr_constant_band(
wav, flux, band="J", snr=100, sampling=sampling
) != snrnorm.snr_constant_wav(wav, flux, wav_ref=1.24, snr=100, sampling=sampling)
def test_snr_normalization_constant(desired_snr, band, testing_spectrum):
"""Test snr_constant_band and snr_constant_wav produce same result."""
wav, flux = testing_spectrum
band_mid = utils.band_middle(band)
assert snrnorm.snr_constant_band(
wav, flux, band=band, snr=desired_snr
) == snrnorm.snr_constant_wav(wav, flux, band_mid, snr=desired_snr)
def test_band_snr_norm_test_data():
"""Compared to wav snr norm."""
# snr_constant_band
star, band, vel, res = "M0", "J", 1.0, "100k"
test_data = os.path.join(eniric.paths["resampled"],
resampled_template.format(star, band, vel, res))
wav, flux = io.pdread_2col(test_data)
assert snrnorm.snr_constant_band(
wav, flux, band="J", snr=100) == snrnorm.snr_constant_wav(wav,
flux,
wav_ref=1.25,
snr=100)
assert snrnorm.snr_constant_band(wav, flux, band="J",
snr=100) != snrnorm.snr_constant_wav(
wav, flux, wav_ref=1.24, snr=100)
def test_snr_constant_band_returns_mid_value_const(band):
size = 100
np.random.seed(40)
flux = 500 * np.random.rand(
size
) # To give a random spectrum (but consistent between tests)
lim = utils.band_limits(band)
wav = np.linspace(lim[0], lim[1], size)
band_const = snrnorm.snr_constant_band(wav, flux, band=band)
wav_const = snrnorm.snr_constant_wav(wav, flux, wav_ref=utils.band_middle(band))
assert isinstance(band_const, float)
assert isinstance(wav_const, float)
assert band_const == wav_const # Since band calls wave at midpoint
def test_snr_normalization_logic(band):
"""Testing direct value.
snr = sqrt(sum(3 pixels))
const = (snr/ref_snr)**2
if pixel value = 3 then the normalization constant will be 1.
"""
size = 100
band = "K"
lim = utils.band_limits(band)
wav = np.linspace(lim[0], lim[1], size)
flux = 3 * np.ones(size)
band_const = snrnorm.snr_constant_band(wav, flux, snr=3, band=band)
wav_const = snrnorm.snr_constant_wav(
wav, flux, snr=3, wav_ref=(lim[0] + lim[1]) / 2
)
assert band_const == 1
assert wav_const == 1