def guess(self, dep, *args, **kwargs):
ref = guess_reference(self.rest.min, self.rest.max, *args)
param_apply_limits(ref, self.rest, **kwargs)
norm = guess_amplitude_at_ref(self.rest.val, dep, *args)
fwhm = get_fwhm(dep, *args)
c_km = 2.99792458e+5
if self.rest.val != 0:
vsini = 2. * fwhm * c_km / numpy.sqrt(3.) / self.rest.val
vs = {'val': vsini,
'min': vsini / _guess_ampl_scale,
'max': vsini * _guess_ampl_scale }
param_apply_limits(vs, self.vsini, **kwargs)
modampl = norm['val'] * numpy.pi * self.vsini.val * \
self.rest.val / 2. / c_km
mod = {'val': modampl,
'min': modampl / _guess_ampl_scale,
'max': modampl * _guess_ampl_scale}
param_apply_limits(mod, self.ampl, **kwargs)
def test_get_fwhm(x, y, expected):
"""Check the FWHM algorithm."""
ans = get_fwhm(y, x)
assert ans == pytest.approx(expected)