def __init__(self, filename=None, wa=[], fl=[], z=0., label=None):
# filename overrides wave and flux keywords
if filename is not None:
if not filename.startswith(PATH_TEMPLATE):
filepath = PATH_TEMPLATE + filename
if filepath.endswith('.fits'):
rec = readtabfits(filepath)
wa, fl = rec.wa, rec.fl
else:
wa, fl = np.loadtxt(filepath, usecols=(0,1), unpack=1)
if label is None:
label = filename
# We keep a copy of the wavelength, flux at z = 0 as it's
# more robust to copy that to self.wa, flux and
# redshift it, rather than repeatedly redshifting
self.z0wa = np.array(wa)
self.z0fl = np.array(fl)
self.wa = np.array(wa)
self.fl = np.array(fl)
self.z = z
self.label = label
# Store the intrinsic (i.e. unextincted) flux in case we
# change extinction
self.EBmV = 0.
self.z0fl_no_extinct = np.array(fl)
if abs(z) > 1e-6:
self.redshift_to(z)
def qso_template(wa, z):
""" Return a composite QSO spectrum at redshift z.
The SDSS composite spectrum as a function of F_lambda is returned
at each wavelength of wa. wa must be in angstroms.
"""
r = readtabfits(DATAPATH + "/templates/qso/dr1QSOspec.fits")
return np.interp(wa, r.wa * (1 + z), r.fl)