def test_vega2ab(self, filt):
"""
test if the convertion between AB and Vega is correct
conversions taken from: http://www.astronomy.ohio-state.edu/~martini/usefuldata.html
absolute tolerance set to 0.15 mag to account for filter differences
Parameters
----------
filt: str
name of the filter
"""
ab2vega = {
"U": 0.79, # magAB - magVega taken from
"B": -0.09, #
"V": 0.02,
"R": 0.21,
"I": 0.45,
"J": 0.91,
"H": 1.39,
"Ks": 1.85
}
sp = Spextrum.flat_spectrum(amplitude=0 * u.ABmag)
magAB = sp.get_magnitude(filt, system_name="AB")
magVega = sp.get_magnitude(filt, system_name="vega")
diff = (magAB.value - magVega.value)
assert np.isclose(diff, ab2vega[filt], atol=0.15)
def test_ref_spectrum_is_right(self, unit):
sp1 = Spextrum.flat_spectrum(amplitude=10 * unit)
sp2 = Spextrum.flat_spectrum(amplitude=11 * unit)
if unit == u.mag:
flux1 = sp1(sp1.waveset[(sp1.waveset.value > 7000 - 200)
& (sp1.waveset.value < 7000 + 200)]).value
flux2 = sp2(sp2.waveset[(sp2.waveset.value > 7000 - 200)
& (sp2.waveset.value < 7000 + 200)]).value
else:
waves = np.arange(1000, 1e4, 1) * u.AA
flux1 = sp1(waves)
flux2 = sp2(waves)
mean = np.mean(flux1 / flux2)
assert np.isclose(mean, 10**0.4)
def test_flat_spectrum(self, unit):
sp = Spextrum.flat_spectrum(amplitude=10 * unit)
assert isinstance(sp, Spextrum)