def __new__(cls, flux, wavelength, scale=None, unit=Angstrom,
wavelength_unit=Angstrom, ivar=None, std=None,
mask=None, dtype=None, copy=True, pixmask_flag=None, **kwargs):
flux = np.array(flux)
# If the scale is defined, creates a new composite unit with the input scale.
if scale is not None:
unit = CompositeUnit(unit.scale * scale, unit.bases, unit.powers)
obj = Quantity(flux, unit=unit, dtype=dtype, copy=copy)
obj = obj.view(cls)
obj._set_unit(unit)
obj.ivar = np.array(ivar) if ivar is not None else None
obj.mask = np.array(mask) if mask is not None else None
if std is not None:
assert ivar is None, 'std and ivar cannot be used at the same time.'
obj._std = np.array(std)
assert wavelength is not None, 'invalid wavelength'
if isinstance(wavelength, Quantity):
obj.wavelength = wavelength
else:
obj.wavelength = np.array(wavelength) * wavelength_unit
obj.pixmask_flag = pixmask_flag
return obj
def __new__(cls,
value,
unit=dimensionless_unscaled,
scale=1,
ivar=None,
mask=None,
dtype=None,
copy=True):
obj = Quantity(value, unit=unit, dtype=dtype, copy=copy)
obj = obj.view(cls)
obj._set_unit(unit)
obj.ivar = ivar
obj.mask = mask
return obj
def __new__(cls, prop, value, ivar=None, mask=None, dtype=None, copy=True):
unit = prop.unit
scale = prop.scale
value = value * scale * unit
obj = Quantity(value, unit=unit, dtype=dtype, copy=copy)
obj = obj.view(cls)
obj._set_unit(unit)
obj.property = prop
obj.ivar = (ivar /
(obj.property.scale**2)) if ivar is not None else None
obj.mask = mask
obj.name = obj.property.name
obj.channel = obj.property.channel
obj.description = obj.property.description
return obj