Exemple #1
0
def dust_transmission(wave,ebv):
    Rv = 3.1
    extinction = ext_odonnell(wave,Rv=Rv)
    return 10**(-Rv*ebv[:,None]*extinction[None,:]/2.5)
Exemple #2
0
def simulate_one_healpix(ifilename,args,model,obsconditions,decam_and_wise_filters,
                         bassmzls_and_wise_filters,footprint_healpix_weight,
                         footprint_healpix_nside,
                         bal=None,sfdmap=None,eboss=None) :
    log = get_logger()

    # open filename and extract basic HEALPix information
    pixel, nside, hpxnest = get_healpix_info(ifilename)

    # using global seed (could be None) get seed for this particular pixel
    global_seed = args.seed
    seed = get_pixel_seed(pixel, nside, global_seed)
    # use this seed to generate future random numbers
    np.random.seed(seed)

    # get output file (we will write there spectra for this HEALPix pixel)
    ofilename = get_spectra_filename(args,nside,pixel)
    # get directory name (we will also write there zbest file)
    pixdir = os.path.dirname(ofilename)

    # get filename for truth file
    truth_filename = get_truth_filename(args,pixdir,nside,pixel)

    # get filename for zbest file
    zbest_filename = get_zbest_filename(args,pixdir,nside,pixel)

    if not args.overwrite :
        # check whether output exists or not
        if args.zbest :
            if os.path.isfile(ofilename) and os.path.isfile(zbest_filename) :
                log.info("skip existing {} and {}".format(ofilename,zbest_filename))
                return
        else : # only test spectra file
            if os.path.isfile(ofilename) :
                log.info("skip existing {}".format(ofilename))
                return

    # create sub-directories if required
    if len(pixdir)>0 :
        if not os.path.isdir(pixdir) :
            log.info("Creating dir {}".format(pixdir))
            os.makedirs(pixdir)

    log.info("Read skewers in {}, random seed = {}".format(ifilename,seed))

    # Read transmission from files. It might include DLA information, and it
    # might add metal transmission as well (from the HDU file).
    log.info("Read transmission file {}".format(ifilename))

    trans_wave, transmission, metadata, dla_info = read_lya_skewers(ifilename,read_dlas=(args.dla=='file'),add_metals=args.metals_from_file,add_lyb=args.add_LYB)

    ### Add Finger-of-God, before generate the continua
    log.info("Add FOG to redshift with sigma {} to quasar redshift".format(args.sigma_kms_fog))
    DZ_FOG = args.sigma_kms_fog/c*(1.+metadata['Z'])*np.random.normal(0,1,metadata['Z'].size)
    metadata['Z'] += DZ_FOG

    ### Select quasar within a given redshift range
    w = (metadata['Z']>=args.zmin) & (metadata['Z']<=args.zmax)
    transmission = transmission[w]
    metadata = metadata[:][w]
    DZ_FOG = DZ_FOG[w]

    # option to make for BOSS+eBOSS
    if not eboss is None:
        if args.downsampling or args.desi_footprint:
            raise ValueError("eboss option can not be run with "
                    +"desi_footprint or downsampling")

        # Get the redshift distribution from SDSS
        selection = sdss_subsample_redshift(metadata["RA"],metadata["DEC"],metadata['Z'],eboss['redshift'])
        log.info("Select QSOs in BOSS+eBOSS redshift distribution {} -> {}".format(metadata['Z'].size,selection.sum()))
        if selection.sum()==0:
            log.warning("No intersection with BOSS+eBOSS redshift distribution")
            return
        transmission = transmission[selection]
        metadata = metadata[:][selection]
        DZ_FOG = DZ_FOG[selection]

        # figure out the density of all quasars
        N_highz = metadata['Z'].size
        # area of healpix pixel, in degrees
        area_deg2 = healpy.pixelfunc.nside2pixarea(nside,degrees=True)
        input_highz_dens_deg2 = N_highz/area_deg2
        selection = sdss_subsample(metadata["RA"], metadata["DEC"],
                        input_highz_dens_deg2,eboss['footprint'])
        log.info("Select QSOs in BOSS+eBOSS footprint {} -> {}".format(transmission.shape[0],selection.size))
        if selection.size == 0 :
            log.warning("No intersection with BOSS+eBOSS footprint")
            return
        transmission = transmission[selection]
        metadata = metadata[:][selection]
        DZ_FOG = DZ_FOG[selection]

    if args.desi_footprint :
        footprint_healpix = footprint.radec2pix(footprint_healpix_nside, metadata["RA"], metadata["DEC"])
        selection = np.where(footprint_healpix_weight[footprint_healpix]>0.99)[0]
        log.info("Select QSOs in DESI footprint {} -> {}".format(transmission.shape[0],selection.size))
        if selection.size == 0 :
            log.warning("No intersection with DESI footprint")
            return
        transmission = transmission[selection]
        metadata = metadata[:][selection]
        DZ_FOG = DZ_FOG[selection]



    nqso=transmission.shape[0]
    if args.downsampling is not None :
        if args.downsampling <= 0 or  args.downsampling > 1 :
           log.error("Down sampling fraction={} must be between 0 and 1".format(args.downsampling))
           raise ValueError("Down sampling fraction={} must be between 0 and 1".format(args.downsampling))
        indices = np.where(np.random.uniform(size=nqso)<args.downsampling)[0]
        if indices.size == 0 :
            log.warning("Down sampling from {} to 0 (by chance I presume)".format(nqso))
            return
        transmission = transmission[indices]
        metadata = metadata[:][indices]
        DZ_FOG = DZ_FOG[indices]
        nqso = transmission.shape[0]

    if args.nmax is not None :
        if args.nmax < nqso :
            log.info("Limit number of QSOs from {} to nmax={} (random subsample)".format(nqso,args.nmax))
            # take a random subsample
            indices = np.random.choice(np.arange(nqso),args.nmax,replace=False)  ##Use random.choice instead of random.uniform (rarely but it does cause a duplication of qsos) 
            transmission = transmission[indices]
            metadata = metadata[:][indices]
            DZ_FOG = DZ_FOG[indices]
            nqso = args.nmax

    # In previous versions of the London mocks we needed to enforce F=1 for
    # z > z_qso here, but this is not needed anymore. Moreover, now we also
    # have metal absorption that implies F < 1 for z > z_qso
    #for ii in range(len(metadata)):
    #    transmission[ii][trans_wave>lambda_RF_LYA*(metadata[ii]['Z']+1)]=1.0

    # if requested, add DLA to the transmission skewers
    if args.dla is not None :

        # if adding random DLAs, we will need a new random generator
        if args.dla=='random':
            log.info('Adding DLAs randomly')
            random_state_just_for_dlas = np.random.RandomState(seed)
        elif args.dla=='file':
            log.info('Adding DLAs from transmission file')
        else:
            log.error("Wrong option for args.dla: "+args.dla)
            sys.exit(1)

        # if adding DLAs, the information will be printed here
        dla_filename=os.path.join(pixdir,"dla-{}-{}.fits".format(nside,pixel))
        dla_NHI, dla_z, dla_qid,dla_id = [], [], [],[]

        # identify minimum Lya redshift in transmission files
        min_lya_z = np.min(trans_wave/lambda_RF_LYA - 1)

        # loop over quasars in pixel

        for ii in range(len(metadata)):

            # quasars with z < min_z will not have any DLA in spectrum
            if min_lya_z>metadata['Z'][ii]: continue

            # quasar ID
            idd=metadata['MOCKID'][ii]
            dlas=[]

            if args.dla=='file':
                for dla in dla_info[dla_info['MOCKID']==idd]:

                    # Adding only DLAs with z < zqso
                    if dla['Z_DLA_RSD']>=metadata['Z'][ii]: continue
                    dlas.append(dict(z=dla['Z_DLA_RSD'],N=dla['N_HI_DLA'],dlaid=dla['DLAID']))
                transmission_dla = dla_spec(trans_wave,dlas)

            elif args.dla=='random':
                dlas, transmission_dla = insert_dlas(trans_wave, metadata['Z'][ii], rstate=random_state_just_for_dlas)
                for idla in dlas:
                   idla['dlaid']+=idd*1000      #Added to have unique DLA ids. Same format as DLAs from file.

            # multiply transmissions and store information for the DLA file
            if len(dlas)>0:
                transmission[ii] = transmission_dla * transmission[ii]
                dla_z += [idla['z'] for idla in dlas]
                dla_NHI += [idla['N'] for idla in dlas]
                dla_id += [idla['dlaid'] for idla in dlas]
                dla_qid += [idd]*len(dlas)
        log.info('Added {} DLAs'.format(len(dla_id)))
        # write file with DLA information
        if len(dla_id)>0:
            dla_meta=Table()
            dla_meta['NHI'] = dla_NHI
            dla_meta['Z_DLA'] = dla_z  #This is Z_DLA_RSD in transmision.
            dla_meta['TARGETID']=dla_qid
            dla_meta['DLAID'] = dla_id
            hdu_dla = pyfits.convenience.table_to_hdu(dla_meta)
            hdu_dla.name="DLA_META"
            del(dla_meta)
            log.info("DLA metadata to be saved in {}".format(truth_filename))
        else:
            hdu_dla=pyfits.PrimaryHDU()
            hdu_dla.name="DLA_META"

    # if requested, extend transmission skewers to cover full spectrum
    if args.target_selection or args.bbflux :
        wanted_min_wave = 3329. # needed to compute magnitudes for decam2014-r (one could have trimmed the transmission file ...)
        wanted_max_wave = 55501. # needed to compute magnitudes for wise2010-W2

        if trans_wave[0]>wanted_min_wave :
            log.info("Increase wavelength range from {}:{} to {}:{} to compute magnitudes".format(int(trans_wave[0]),int(trans_wave[-1]),int(wanted_min_wave),int(trans_wave[-1])))
            # pad with ones at short wavelength, we assume F = 1 for z <~ 1.7
            # we don't need any wavelength resolution here
            new_trans_wave = np.append([wanted_min_wave,trans_wave[0]-0.01],trans_wave)
            new_transmission = np.ones((transmission.shape[0],new_trans_wave.size))
            new_transmission[:,2:] = transmission
            trans_wave   = new_trans_wave
            transmission = new_transmission

        if trans_wave[-1]<wanted_max_wave :
            log.info("Increase wavelength range from {}:{} to {}:{} to compute magnitudes".format(int(trans_wave[0]),int(trans_wave[-1]),int(trans_wave[0]),int(wanted_max_wave)))
            # pad with ones at long wavelength because we assume F = 1
            coarse_dwave = 2. # we don't care about resolution, we just need a decent QSO spectrum, there is no IGM transmission in this range
            n = int((wanted_max_wave-trans_wave[-1])/coarse_dwave)+1
            new_trans_wave = np.append(trans_wave,np.linspace(trans_wave[-1]+coarse_dwave,trans_wave[-1]+coarse_dwave*(n+1),n))
            new_transmission = np.ones((transmission.shape[0],new_trans_wave.size))
            new_transmission[:,:trans_wave.size] = transmission
            trans_wave   = new_trans_wave
            transmission = new_transmission

    # whether to use QSO or SIMQSO to generate quasar continua.  Simulate
    # spectra in the north vs south separately because they're on different
    # photometric systems.
    south = np.where( is_south(metadata['DEC']) )[0]
    north = np.where( ~is_south(metadata['DEC']) )[0]
    meta, qsometa = empty_metatable(nqso, objtype='QSO', simqso=not args.no_simqso)
    if args.no_simqso:
        log.info("Simulate {} QSOs with QSO templates".format(nqso))
        tmp_qso_flux = np.zeros([nqso, len(model.eigenwave)], dtype='f4')
        tmp_qso_wave = np.zeros_like(tmp_qso_flux)
    else:
        log.info("Simulate {} QSOs with SIMQSO templates".format(nqso))
        tmp_qso_flux = np.zeros([nqso, len(model.basewave)], dtype='f4')
        tmp_qso_wave = model.basewave

    for these, issouth in zip( (north, south), (False, True) ):

        # number of quasars in these
        nt = len(these)
        if nt<=0: continue

        if not eboss is None:
            # for eBOSS, generate only quasars with r<22
            magrange = (17.0, 21.3)
            _tmp_qso_flux, _tmp_qso_wave, _meta, _qsometa \
                = model.make_templates(nmodel=nt,
                    redshift=metadata['Z'][these], magrange=magrange,
                    lyaforest=False, nocolorcuts=True,
                    noresample=True, seed=seed, south=issouth)
        else:
            _tmp_qso_flux, _tmp_qso_wave, _meta, _qsometa \
                = model.make_templates(nmodel=nt,
                    redshift=metadata['Z'][these],
                    lyaforest=False, nocolorcuts=True,
                    noresample=True, seed=seed, south=issouth)

        _meta['TARGETID'] = metadata['MOCKID'][these]
        _qsometa['TARGETID'] = metadata['MOCKID'][these]
        meta[these] = _meta
        qsometa[these] = _qsometa
        tmp_qso_flux[these, :] = _tmp_qso_flux

        if args.no_simqso:
            tmp_qso_wave[these, :] = _tmp_qso_wave

    log.info("Resample to transmission wavelength grid")
    qso_flux=np.zeros((tmp_qso_flux.shape[0],trans_wave.size))
    if args.no_simqso:
        for q in range(tmp_qso_flux.shape[0]) :
            qso_flux[q]=np.interp(trans_wave,tmp_qso_wave[q],tmp_qso_flux[q])
    else:
        for q in range(tmp_qso_flux.shape[0]) :
            qso_flux[q]=np.interp(trans_wave,tmp_qso_wave,tmp_qso_flux[q])

    tmp_qso_flux = qso_flux
    tmp_qso_wave = trans_wave

    # if requested, add BAL features to the quasar continua
    if args.balprob:
        if args.balprob<=1. and args.balprob >0:
            log.info("Adding BALs with probability {}".format(args.balprob))
            # save current random state
            rnd_state = np.random.get_state()
            tmp_qso_flux,meta_bal=bal.insert_bals(tmp_qso_wave,tmp_qso_flux, metadata['Z'],
                                                  balprob=args.balprob,seed=seed)
            # restore random state to get the same random numbers later
            # as when we don't insert BALs
            np.random.set_state(rnd_state)
            meta_bal['TARGETID'] = metadata['MOCKID']
            w = meta_bal['TEMPLATEID']!=-1
            meta_bal = meta_bal[:][w]
            hdu_bal=pyfits.convenience.table_to_hdu(meta_bal); hdu_bal.name="BAL_META"
            del meta_bal
        else:
            balstr=str(args.balprob)
            log.error("BAL probability is not between 0 and 1 : "+balstr)
            sys.exit(1)

    # Multiply quasar continua by transmitted flux fraction
    # (at this point transmission file might include Ly-beta, metals and DLAs)
    log.info("Apply transmitted flux fraction")
    if not args.no_transmission:
        tmp_qso_flux = apply_lya_transmission(tmp_qso_wave,tmp_qso_flux,
                            trans_wave,transmission)

    # if requested, compute metal transmission on the fly
    # (if not included already from the transmission file)
    if args.metals is not None:
        if args.metals_from_file :
            log.error('you cannot add metals twice')
            raise ValueError('you cannot add metals twice')
        if args.no_transmission:
            log.error('you cannot add metals if asking for no-transmission')
            raise ValueError('can not add metals if using no-transmission')
        lstMetals = ''
        for m in args.metals: lstMetals += m+', '
        log.info("Apply metals: {}".format(lstMetals[:-2]))

        tmp_qso_flux = apply_metals_transmission(tmp_qso_wave,tmp_qso_flux,
                            trans_wave,transmission,args.metals)

    # if requested, compute magnitudes and apply target selection.  Need to do
    # this calculation separately for QSOs in the north vs south.
    bbflux=None
    if args.target_selection or args.bbflux :
        bands=['FLUX_G','FLUX_R','FLUX_Z', 'FLUX_W1', 'FLUX_W2']
        bbflux=dict()
        bbflux['SOUTH'] = is_south(metadata['DEC'])
        for band in bands:
            bbflux[band] = np.zeros(nqso)
        # need to recompute the magnitudes to account for lya transmission
        log.info("Compute QSO magnitudes")

        for these, filters in zip( (~bbflux['SOUTH'], bbflux['SOUTH']),
                                   (bassmzls_and_wise_filters, decam_and_wise_filters) ):
            if np.count_nonzero(these) > 0:
                maggies = filters.get_ab_maggies(1e-17 * tmp_qso_flux[these, :], tmp_qso_wave)
                for band, filt in zip( bands, maggies.colnames ):
                    bbflux[band][these] = np.ma.getdata(1e9 * maggies[filt]) # nanomaggies

    if args.target_selection :
        log.info("Apply target selection")
        isqso = np.ones(nqso, dtype=bool)
        for these, issouth in zip( (~bbflux['SOUTH'], bbflux['SOUTH']), (False, True) ):
            if np.count_nonzero(these) > 0:
                # optical cuts only if using QSO vs SIMQSO
                isqso[these] &= isQSO_colors(gflux=bbflux['FLUX_G'][these],
                                             rflux=bbflux['FLUX_R'][these],
                                             zflux=bbflux['FLUX_Z'][these],
                                             w1flux=bbflux['FLUX_W1'][these],
                                             w2flux=bbflux['FLUX_W2'][these],
                                             south=issouth, optical=args.no_simqso)

        log.info("Target selection: {}/{} QSOs selected".format(np.sum(isqso),nqso))
        selection=np.where(isqso)[0]
        if selection.size==0 : return
        tmp_qso_flux = tmp_qso_flux[selection]
        metadata     = metadata[:][selection]
        meta         = meta[:][selection]
        qsometa      = qsometa[:][selection]
        DZ_FOG      = DZ_FOG[selection]
        for band in bands :
            bbflux[band] = bbflux[band][selection]
        bbflux['SOUTH']=bbflux['SOUTH'][selection]  
            
        nqso         = selection.size

    log.info("Resample to a linear wavelength grid (needed by DESI sim.)")
    # careful integration of bins, not just a simple interpolation
    qso_wave=np.linspace(args.wmin,args.wmax,int((args.wmax-args.wmin)/args.dwave)+1)
    qso_flux=np.zeros((tmp_qso_flux.shape[0],qso_wave.size))
    for q in range(tmp_qso_flux.shape[0]) :
        qso_flux[q]=resample_flux(qso_wave,tmp_qso_wave,tmp_qso_flux[q])

    log.info("Simulate DESI observation and write output file")
    if "MOCKID" in metadata.dtype.names :
        #log.warning("Using MOCKID as TARGETID")
        targetid=np.array(metadata["MOCKID"]).astype(int)
    elif "ID" in metadata.dtype.names :
        log.warning("Using ID as TARGETID")
        targetid=np.array(metadata["ID"]).astype(int)
    else :
        log.warning("No TARGETID")
        targetid=None

    specmeta={"HPXNSIDE":nside,"HPXPIXEL":pixel, "HPXNEST":hpxnest}

    if args.target_selection or args.bbflux :
        fibermap_columns = dict(
            FLUX_G = bbflux['FLUX_G'],
            FLUX_R = bbflux['FLUX_R'],
            FLUX_Z = bbflux['FLUX_Z'],
            FLUX_W1 = bbflux['FLUX_W1'],
            FLUX_W2 = bbflux['FLUX_W2'],
            )
        photsys = np.full(len(bbflux['FLUX_G']), 'N', dtype='S1')
        photsys[bbflux['SOUTH']] = b'S'
        fibermap_columns['PHOTSYS'] = photsys
    else :
        fibermap_columns=None

    # Attenuate the spectra for extinction
    if not sfdmap is None:
       Rv=3.1   #set by default
       indx=np.arange(metadata['RA'].size)
       extinction =Rv*ext_odonnell(qso_wave)
       EBV = sfdmap.ebv(metadata['RA'],metadata['DEC'], scaling=1.0)
       qso_flux *=10**( -0.4 * EBV[indx, np.newaxis] * extinction)
       if fibermap_columns is not None:
          fibermap_columns['EBV']=EBV
       EBV0=0.0
       EBV_med=np.median(EBV)
       Ag = 3.303 * (EBV_med - EBV0)
       exptime_fact=np.power(10.0, (2.0 * Ag / 2.5))
       obsconditions['EXPTIME']*=exptime_fact
       log.info("Dust extinction added")
       log.info('exposure time adjusted to {}'.format(obsconditions['EXPTIME']))

    sim_spectra(qso_wave,qso_flux, args.program, obsconditions=obsconditions,spectra_filename=ofilename,
                sourcetype="qso", skyerr=args.skyerr,ra=metadata["RA"],dec=metadata["DEC"],targetid=targetid,
                meta=specmeta,seed=seed,fibermap_columns=fibermap_columns,use_poisson=False) # use Poisson = False to get reproducible results.

    ### Keep input redshift
    Z_spec = metadata['Z'].copy()
    Z_input = metadata['Z'].copy()-DZ_FOG

    ### Add a shift to the redshift, simulating the systematic imprecision of redrock
    DZ_sys_shift = args.shift_kms_los/c*(1.+Z_input)
    log.info('Added a shift of {} km/s to the redshift'.format(args.shift_kms_los))
    meta['REDSHIFT'] += DZ_sys_shift
    metadata['Z'] += DZ_sys_shift

    ### Add a shift to the redshift, simulating the statistic imprecision of redrock
    if args.gamma_kms_zfit:
        log.info("Added zfit error with gamma {} to zbest".format(args.gamma_kms_zfit))
        DZ_stat_shift = mod_cauchy(loc=0,scale=args.gamma_kms_zfit,size=nqso,cut=3000)/c*(1.+Z_input)
        meta['REDSHIFT'] += DZ_stat_shift
        metadata['Z'] += DZ_stat_shift

    ## Write the truth file, including metadata for DLAs and BALs
    log.info('Writing a truth file  {}'.format(truth_filename))
    meta.rename_column('REDSHIFT','Z')
    meta.add_column(Column(Z_spec,name='TRUEZ'))
    meta.add_column(Column(Z_input,name='Z_INPUT'))
    meta.add_column(Column(DZ_FOG,name='DZ_FOG'))
    meta.add_column(Column(DZ_sys_shift,name='DZ_SYS'))
    if args.gamma_kms_zfit:
        meta.add_column(Column(DZ_stat_shift,name='DZ_STAT'))
    if 'Z_noRSD' in metadata.dtype.names:
        meta.add_column(Column(metadata['Z_noRSD'],name='Z_NORSD'))
    else:
        log.info('Z_noRSD field not present in transmission file. Z_NORSD not saved to truth file')

    #Save global seed and pixel seed to primary header
    hdr=pyfits.Header()
    hdr['GSEED']=global_seed
    hdr['PIXSEED']=seed
    hdu = pyfits.convenience.table_to_hdu(meta)
    hdu.header['EXTNAME'] = 'TRUTH'
    hduqso=pyfits.convenience.table_to_hdu(qsometa)
    hduqso.header['EXTNAME'] = 'QSO_META'
    hdulist=pyfits.HDUList([pyfits.PrimaryHDU(header=hdr),hdu,hduqso])
    if args.dla:
        hdulist.append(hdu_dla)
    if args.balprob:
        hdulist.append(hdu_bal)
    hdulist.writeto(truth_filename, overwrite=True)
    hdulist.close()




    if args.zbest :
        log.info("Read fibermap")
        fibermap = read_fibermap(ofilename)
        log.info("Writing a zbest file {}".format(zbest_filename))
        columns = [
            ('CHI2', 'f8'),
            ('COEFF', 'f8' , (4,)),
            ('Z', 'f8'),
            ('ZERR', 'f8'),
            ('ZWARN', 'i8'),
            ('SPECTYPE', (str,96)),
            ('SUBTYPE', (str,16)),
            ('TARGETID', 'i8'),
            ('DELTACHI2', 'f8'),
            ('BRICKNAME', (str,8))]
        zbest = Table(np.zeros(nqso, dtype=columns))
        zbest['CHI2'][:] = 0.
        zbest['Z'][:] = metadata['Z']
        zbest['ZERR'][:] = 0.
        zbest['ZWARN'][:] = 0
        zbest['SPECTYPE'][:] = 'QSO'
        zbest['SUBTYPE'][:] = ''
        zbest['TARGETID'][:] = metadata['MOCKID']
        zbest['DELTACHI2'][:] = 25.
        hzbest = pyfits.convenience.table_to_hdu(zbest); hzbest.name='ZBEST'
        hfmap  = pyfits.convenience.table_to_hdu(fibermap);  hfmap.name='FIBERMAP'
        hdulist =pyfits.HDUList([pyfits.PrimaryHDU(),hzbest,hfmap])
        hdulist.writeto(zbest_filename, overwrite=True)
        hdulist.close() # see if this helps with memory issue
Exemple #3
0
def simulate_one_healpix(ifilename,args,model,obsconditions,decam_and_wise_filters,
                         bassmzls_and_wise_filters,footprint_healpix_weight,
                         footprint_healpix_nside,
                         bal=None,sfdmap=None,eboss=None) :
    log = get_logger()

    # open filename and extract basic HEALPix information
    pixel, nside, hpxnest = get_healpix_info(ifilename)

    # using global seed (could be None) get seed for this particular pixel
    global_seed = args.seed
    seed = get_pixel_seed(pixel, nside, global_seed)
    # use this seed to generate future random numbers
    np.random.seed(seed)

    # get output file (we will write there spectra for this HEALPix pixel)
    ofilename = get_spectra_filename(args,nside,pixel)
    # get directory name (we will also write there zbest file)
    pixdir = os.path.dirname(ofilename)

    # get filename for truth file
    truth_filename = get_truth_filename(args,pixdir,nside,pixel)

    # get filename for zbest file
    zbest_filename = get_zbest_filename(args,pixdir,nside,pixel)

    if not args.overwrite :
        # check whether output exists or not
        if args.zbest :
            if os.path.isfile(ofilename) and os.path.isfile(zbest_filename) :
                log.info("skip existing {} and {}".format(ofilename,zbest_filename))
                return
        else : # only test spectra file
            if os.path.isfile(ofilename) :
                log.info("skip existing {}".format(ofilename))
                return

    # create sub-directories if required
    if len(pixdir)>0 :
        if not os.path.isdir(pixdir) :
            log.info("Creating dir {}".format(pixdir))
            os.makedirs(pixdir)

    log.info("Read skewers in {}, random seed = {}".format(ifilename,seed))

    # Read transmission from files. It might include DLA information, and it
    # might add metal transmission as well (from the HDU file).
    log.info("Read transmission file {}".format(ifilename))
    trans_wave, transmission, metadata, dla_info = read_lya_skewers(ifilename,read_dlas=(args.dla=='file'),add_metals=args.metals_from_file)

    ### Add Finger-of-God, before generate the continua
    log.info("Add FOG to redshift with sigma {} to quasar redshift".format(args.sigma_kms_fog))
    DZ_FOG = args.sigma_kms_fog/c*(1.+metadata['Z'])*np.random.normal(0,1,metadata['Z'].size)
    metadata['Z'] += DZ_FOG

    ### Select quasar within a given redshift range
    w = (metadata['Z']>=args.zmin) & (metadata['Z']<=args.zmax)
    transmission = transmission[w]
    metadata = metadata[:][w]
    DZ_FOG = DZ_FOG[w]

    # option to make for BOSS+eBOSS
    if not eboss is None:
        if args.downsampling or args.desi_footprint:
            raise ValueError("eboss option can not be run with "
                    +"desi_footprint or downsampling")

        # Get the redshift distribution from SDSS
        selection = sdss_subsample_redshift(metadata["RA"],metadata["DEC"],metadata['Z'],eboss['redshift'])
        log.info("Select QSOs in BOSS+eBOSS redshift distribution {} -> {}".format(metadata['Z'].size,selection.sum()))
        if selection.sum()==0:
            log.warning("No intersection with BOSS+eBOSS redshift distribution")
            return
        transmission = transmission[selection]
        metadata = metadata[:][selection]
        DZ_FOG = DZ_FOG[selection]

        # figure out the density of all quasars
        N_highz = metadata['Z'].size
        # area of healpix pixel, in degrees
        area_deg2 = healpy.pixelfunc.nside2pixarea(nside,degrees=True)
        input_highz_dens_deg2 = N_highz/area_deg2
        selection = sdss_subsample(metadata["RA"], metadata["DEC"],
                        input_highz_dens_deg2,eboss['footprint'])
        log.info("Select QSOs in BOSS+eBOSS footprint {} -> {}".format(transmission.shape[0],selection.size))
        if selection.size == 0 :
            log.warning("No intersection with BOSS+eBOSS footprint")
            return
        transmission = transmission[selection]
        metadata = metadata[:][selection]
        DZ_FOG = DZ_FOG[selection]

    if args.desi_footprint :
        footprint_healpix = footprint.radec2pix(footprint_healpix_nside, metadata["RA"], metadata["DEC"])
        selection = np.where(footprint_healpix_weight[footprint_healpix]>0.99)[0]
        log.info("Select QSOs in DESI footprint {} -> {}".format(transmission.shape[0],selection.size))
        if selection.size == 0 :
            log.warning("No intersection with DESI footprint")
            return
        transmission = transmission[selection]
        metadata = metadata[:][selection]
        DZ_FOG = DZ_FOG[selection]



    nqso=transmission.shape[0]
    if args.downsampling is not None :
        if args.downsampling <= 0 or  args.downsampling > 1 :
           log.error("Down sampling fraction={} must be between 0 and 1".format(args.downsampling))
           raise ValueError("Down sampling fraction={} must be between 0 and 1".format(args.downsampling))
        indices = np.where(np.random.uniform(size=nqso)<args.downsampling)[0]
        if indices.size == 0 :
            log.warning("Down sampling from {} to 0 (by chance I presume)".format(nqso))
            return
        transmission = transmission[indices]
        metadata = metadata[:][indices]
        DZ_FOG = DZ_FOG[indices]
        nqso = transmission.shape[0]

    if args.nmax is not None :
        if args.nmax < nqso :
            log.info("Limit number of QSOs from {} to nmax={} (random subsample)".format(nqso,args.nmax))
            # take a random subsample
            indices = (np.random.uniform(size=args.nmax)*nqso).astype(int)
            transmission = transmission[indices]
            metadata = metadata[:][indices]
            DZ_FOG = DZ_FOG[indices]
            nqso = args.nmax

    # In previous versions of the London mocks we needed to enforce F=1 for
    # z > z_qso here, but this is not needed anymore. Moreover, now we also
    # have metal absorption that implies F < 1 for z > z_qso
    #for ii in range(len(metadata)):
    #    transmission[ii][trans_wave>lambda_RF_LYA*(metadata[ii]['Z']+1)]=1.0

    # if requested, add DLA to the transmission skewers
    if args.dla is not None :

        # if adding random DLAs, we will need a new random generator
        if args.dla=='random':
            log.info('Adding DLAs randomly')
            random_state_just_for_dlas = np.random.RandomState(seed)
        elif args.dla=='file':
            log.info('Adding DLAs from transmission file')
        else:
            log.error("Wrong option for args.dla: "+args.dla)
            sys.exit(1)

        # if adding DLAs, the information will be printed here
        dla_filename=os.path.join(pixdir,"dla-{}-{}.fits".format(nside,pixel))
        dla_NHI, dla_z, dla_qid,dla_id = [], [], [],[]

        # identify minimum Lya redshift in transmission files
        min_lya_z = np.min(trans_wave/lambda_RF_LYA - 1)

        # loop over quasars in pixel

        for ii in range(len(metadata)):

            # quasars with z < min_z will not have any DLA in spectrum
            if min_lya_z>metadata['Z'][ii]: continue

            # quasar ID
            idd=metadata['MOCKID'][ii]
            dlas=[]

            if args.dla=='file':
                for dla in dla_info[dla_info['MOCKID']==idd]:

                    # Adding only DLAs with z < zqso
                    if dla['Z_DLA_RSD']>=metadata['Z'][ii]: continue
                    dlas.append(dict(z=dla['Z_DLA_RSD'],N=dla['N_HI_DLA'],dlaid=dla['DLAID']))
                transmission_dla = dla_spec(trans_wave,dlas)

            elif args.dla=='random':
                dlas, transmission_dla = insert_dlas(trans_wave, metadata['Z'][ii], rstate=random_state_just_for_dlas)
                for idla in dlas:
                   idla['dlaid']+=idd*1000      #Added to have unique DLA ids. Same format as DLAs from file.

            # multiply transmissions and store information for the DLA file
            if len(dlas)>0:
                transmission[ii] = transmission_dla * transmission[ii]
                dla_z += [idla['z'] for idla in dlas]
                dla_NHI += [idla['N'] for idla in dlas]
                dla_id += [idla['dlaid'] for idla in dlas]
                dla_qid += [idd]*len(dlas)
        log.info('Added {} DLAs'.format(len(dla_id)))
        # write file with DLA information
        if len(dla_id)>0:
            dla_meta=Table()
            dla_meta['NHI'] = dla_NHI
            dla_meta['Z_DLA'] = dla_z  #This is Z_DLA_RSD in transmision.
            dla_meta['TARGETID']=dla_qid
            dla_meta['DLAID'] = dla_id
            hdu_dla = pyfits.convenience.table_to_hdu(dla_meta)
            hdu_dla.name="DLA_META"
            del(dla_meta)
            log.info("DLA metadata to be saved in {}".format(truth_filename))
        else:
            hdu_dla=pyfits.PrimaryHDU()
            hdu_dla.name="DLA_META"

    # if requested, extend transmission skewers to cover full spectrum
    if args.target_selection or args.bbflux :
        wanted_min_wave = 3329. # needed to compute magnitudes for decam2014-r (one could have trimmed the transmission file ...)
        wanted_max_wave = 55501. # needed to compute magnitudes for wise2010-W2

        if trans_wave[0]>wanted_min_wave :
            log.info("Increase wavelength range from {}:{} to {}:{} to compute magnitudes".format(int(trans_wave[0]),int(trans_wave[-1]),int(wanted_min_wave),int(trans_wave[-1])))
            # pad with ones at short wavelength, we assume F = 1 for z <~ 1.7
            # we don't need any wavelength resolution here
            new_trans_wave = np.append([wanted_min_wave,trans_wave[0]-0.01],trans_wave)
            new_transmission = np.ones((transmission.shape[0],new_trans_wave.size))
            new_transmission[:,2:] = transmission
            trans_wave   = new_trans_wave
            transmission = new_transmission

        if trans_wave[-1]<wanted_max_wave :
            log.info("Increase wavelength range from {}:{} to {}:{} to compute magnitudes".format(int(trans_wave[0]),int(trans_wave[-1]),int(trans_wave[0]),int(wanted_max_wave)))
            # pad with ones at long wavelength because we assume F = 1
            coarse_dwave = 2. # we don't care about resolution, we just need a decent QSO spectrum, there is no IGM transmission in this range
            n = int((wanted_max_wave-trans_wave[-1])/coarse_dwave)+1
            new_trans_wave = np.append(trans_wave,np.linspace(trans_wave[-1]+coarse_dwave,trans_wave[-1]+coarse_dwave*(n+1),n))
            new_transmission = np.ones((transmission.shape[0],new_trans_wave.size))
            new_transmission[:,:trans_wave.size] = transmission
            trans_wave   = new_trans_wave
            transmission = new_transmission

    # whether to use QSO or SIMQSO to generate quasar continua.  Simulate
    # spectra in the north vs south separately because they're on different
    # photometric systems.
    south = np.where( is_south(metadata['DEC']) )[0]
    north = np.where( ~is_south(metadata['DEC']) )[0]
    meta, qsometa = empty_metatable(nqso, objtype='QSO', simqso=not args.no_simqso)
    if args.no_simqso:
        log.info("Simulate {} QSOs with QSO templates".format(nqso))
        tmp_qso_flux = np.zeros([nqso, len(model.eigenwave)], dtype='f4')
        tmp_qso_wave = np.zeros_like(tmp_qso_flux)
    else:
        log.info("Simulate {} QSOs with SIMQSO templates".format(nqso))
        tmp_qso_flux = np.zeros([nqso, len(model.basewave)], dtype='f4')
        tmp_qso_wave = model.basewave

    for these, issouth in zip( (north, south), (False, True) ):

        # number of quasars in these
        nt = len(these)
        if nt<=0: continue

        if not eboss is None:
            # for eBOSS, generate only quasars with r<22
            magrange = (17.0, 21.3)
            _tmp_qso_flux, _tmp_qso_wave, _meta, _qsometa \
                = model.make_templates(nmodel=nt,
                    redshift=metadata['Z'][these], magrange=magrange,
                    lyaforest=False, nocolorcuts=True,
                    noresample=True, seed=seed, south=issouth)
        else:
            _tmp_qso_flux, _tmp_qso_wave, _meta, _qsometa \
                = model.make_templates(nmodel=nt,
                    redshift=metadata['Z'][these],
                    lyaforest=False, nocolorcuts=True,
                    noresample=True, seed=seed, south=issouth)

        _meta['TARGETID'] = metadata['MOCKID'][these]
        _qsometa['TARGETID'] = metadata['MOCKID'][these]
        meta[these] = _meta
        qsometa[these] = _qsometa
        tmp_qso_flux[these, :] = _tmp_qso_flux

        if args.no_simqso:
            tmp_qso_wave[these, :] = _tmp_qso_wave

    log.info("Resample to transmission wavelength grid")
    qso_flux=np.zeros((tmp_qso_flux.shape[0],trans_wave.size))
    if args.no_simqso:
        for q in range(tmp_qso_flux.shape[0]) :
            qso_flux[q]=np.interp(trans_wave,tmp_qso_wave[q],tmp_qso_flux[q])
    else:
        for q in range(tmp_qso_flux.shape[0]) :
            qso_flux[q]=np.interp(trans_wave,tmp_qso_wave,tmp_qso_flux[q])

    tmp_qso_flux = qso_flux
    tmp_qso_wave = trans_wave

    # if requested, add BAL features to the quasar continua
    if args.balprob:
        if args.balprob<=1. and args.balprob >0:
            log.info("Adding BALs with probability {}".format(args.balprob))
            # save current random state
            rnd_state = np.random.get_state()
            tmp_qso_flux,meta_bal=bal.insert_bals(tmp_qso_wave,tmp_qso_flux, metadata['Z'],
                                                  balprob=args.balprob,seed=seed)
            # restore random state to get the same random numbers later
            # as when we don't insert BALs
            np.random.set_state(rnd_state)
            meta_bal['TARGETID'] = metadata['MOCKID']
            w = meta_bal['TEMPLATEID']!=-1
            meta_bal = meta_bal[:][w]
            hdu_bal=pyfits.convenience.table_to_hdu(meta_bal); hdu_bal.name="BAL_META"
            del meta_bal
        else:
            balstr=str(args.balprob)
            log.error("BAL probability is not between 0 and 1 : "+balstr)
            sys.exit(1)

    # Multiply quasar continua by transmitted flux fraction
    # (at this point transmission file might include Ly-beta, metals and DLAs)
    log.info("Apply transmitted flux fraction")
    if not args.no_transmission:
        tmp_qso_flux = apply_lya_transmission(tmp_qso_wave,tmp_qso_flux,
                            trans_wave,transmission)

    # if requested, compute metal transmission on the fly
    # (if not included already from the transmission file)
    if args.metals is not None:
        if args.metals_from_file:
            log.error('you cannot add metals twice')
            raise ValueError('you cannot add metals twice')
        if args.no_transmission:
            log.error('you cannot add metals if asking for no-transmission')
            raise ValueError('can not add metals if using no-transmission')
        lstMetals = ''
        for m in args.metals: lstMetals += m+', '
        log.info("Apply metals: {}".format(lstMetals[:-2]))

        tmp_qso_flux = apply_metals_transmission(tmp_qso_wave,tmp_qso_flux,
                            trans_wave,transmission,args.metals)

    # if requested, compute magnitudes and apply target selection.  Need to do
    # this calculation separately for QSOs in the north vs south.
    bbflux=None
    if args.target_selection or args.bbflux :
        bands=['FLUX_G','FLUX_R','FLUX_Z', 'FLUX_W1', 'FLUX_W2']
        bbflux=dict()
        bbflux['SOUTH'] = is_south(metadata['DEC'])
        for band in bands:
            bbflux[band] = np.zeros(nqso)
        # need to recompute the magnitudes to account for lya transmission
        log.info("Compute QSO magnitudes")

        for these, filters in zip( (~bbflux['SOUTH'], bbflux['SOUTH']),
                                   (bassmzls_and_wise_filters, decam_and_wise_filters) ):
            if np.count_nonzero(these) > 0:
                maggies = filters.get_ab_maggies(1e-17 * tmp_qso_flux[these, :], tmp_qso_wave)
                for band, filt in zip( bands, maggies.colnames ):
                    bbflux[band][these] = np.ma.getdata(1e9 * maggies[filt]) # nanomaggies

    if args.target_selection :
        log.info("Apply target selection")
        isqso = np.ones(nqso, dtype=bool)
        for these, issouth in zip( (~bbflux['SOUTH'], bbflux['SOUTH']), (False, True) ):
            if np.count_nonzero(these) > 0:
                # optical cuts only if using QSO vs SIMQSO
                isqso[these] &= isQSO_colors(gflux=bbflux['FLUX_G'][these],
                                             rflux=bbflux['FLUX_R'][these],
                                             zflux=bbflux['FLUX_Z'][these],
                                             w1flux=bbflux['FLUX_W1'][these],
                                             w2flux=bbflux['FLUX_W2'][these],
                                             south=issouth, optical=args.no_simqso)

        log.info("Target selection: {}/{} QSOs selected".format(np.sum(isqso),nqso))
        selection=np.where(isqso)[0]
        if selection.size==0 : return
        tmp_qso_flux = tmp_qso_flux[selection]
        metadata     = metadata[:][selection]
        meta         = meta[:][selection]
        qsometa      = qsometa[:][selection]
        DZ_FOG      = DZ_FOG[selection]

        for band in bands :
            bbflux[band] = bbflux[band][selection]
        nqso         = selection.size

    log.info("Resample to a linear wavelength grid (needed by DESI sim.)")
    # careful integration of bins, not just a simple interpolation
    qso_wave=np.linspace(args.wmin,args.wmax,int((args.wmax-args.wmin)/args.dwave)+1)
    qso_flux=np.zeros((tmp_qso_flux.shape[0],qso_wave.size))
    for q in range(tmp_qso_flux.shape[0]) :
        qso_flux[q]=resample_flux(qso_wave,tmp_qso_wave,tmp_qso_flux[q])

    log.info("Simulate DESI observation and write output file")
    if "MOCKID" in metadata.dtype.names :
        #log.warning("Using MOCKID as TARGETID")
        targetid=np.array(metadata["MOCKID"]).astype(int)
    elif "ID" in metadata.dtype.names :
        log.warning("Using ID as TARGETID")
        targetid=np.array(metadata["ID"]).astype(int)
    else :
        log.warning("No TARGETID")
        targetid=None

    specmeta={"HPXNSIDE":nside,"HPXPIXEL":pixel, "HPXNEST":hpxnest}

    if args.target_selection or args.bbflux :
        fibermap_columns = dict(
            FLUX_G = bbflux['FLUX_G'],
            FLUX_R = bbflux['FLUX_R'],
            FLUX_Z = bbflux['FLUX_Z'],
            FLUX_W1 = bbflux['FLUX_W1'],
            FLUX_W2 = bbflux['FLUX_W2'],
            )
        photsys = np.full(len(bbflux['FLUX_G']), 'N', dtype='S1')
        photsys[bbflux['SOUTH']] = b'S'
        fibermap_columns['PHOTSYS'] = photsys
    else :
        fibermap_columns=None

    # Attenuate the spectra for extinction
    if not sfdmap is None:
       Rv=3.1   #set by default
       indx=np.arange(metadata['RA'].size)
       extinction =Rv*ext_odonnell(qso_wave)
       EBV = sfdmap.ebv(metadata['RA'],metadata['DEC'], scaling=1.0)
       qso_flux *=10**( -0.4 * EBV[indx, np.newaxis] * extinction)
       if fibermap_columns is not None:
          fibermap_columns['EBV']=EBV
       EBV0=0.0
       EBV_med=np.median(EBV)
       Ag = 3.303 * (EBV_med - EBV0)
       exptime_fact=np.power(10.0, (2.0 * Ag / 2.5))
       obsconditions['EXPTIME']*=exptime_fact
       log.info("Dust extinction added")
       log.info('exposure time adjusted to {}'.format(obsconditions['EXPTIME']))

    sim_spectra(qso_wave,qso_flux, args.program, obsconditions=obsconditions,spectra_filename=ofilename,
                sourcetype="qso", skyerr=args.skyerr,ra=metadata["RA"],dec=metadata["DEC"],targetid=targetid,
                meta=specmeta,seed=seed,fibermap_columns=fibermap_columns,use_poisson=False) # use Poisson = False to get reproducible results.

    ### Keep input redshift
    Z_spec = metadata['Z'].copy()
    Z_input = metadata['Z'].copy()-DZ_FOG

    ### Add a shift to the redshift, simulating the systematic imprecision of redrock
    DZ_sys_shift = args.shift_kms_los/c*(1.+Z_input)
    log.info('Added a shift of {} km/s to the redshift'.format(args.shift_kms_los))
    meta['REDSHIFT'] += DZ_sys_shift
    metadata['Z'] += DZ_sys_shift

    ### Add a shift to the redshift, simulating the statistic imprecision of redrock
    if args.gamma_kms_zfit:
        log.info("Added zfit error with gamma {} to zbest".format(args.gamma_kms_zfit))
        DZ_stat_shift = mod_cauchy(loc=0,scale=args.gamma_kms_zfit,size=nqso,cut=3000)/c*(1.+Z_input)
        meta['REDSHIFT'] += DZ_stat_shift
        metadata['Z'] += DZ_stat_shift

    ## Write the truth file, including metadata for DLAs and BALs
    log.info('Writing a truth file  {}'.format(truth_filename))
    meta.rename_column('REDSHIFT','Z')
    meta.add_column(Column(Z_spec,name='TRUEZ'))
    meta.add_column(Column(Z_input,name='Z_INPUT'))
    meta.add_column(Column(DZ_FOG,name='DZ_FOG'))
    meta.add_column(Column(DZ_sys_shift,name='DZ_SYS'))
    if args.gamma_kms_zfit:
        meta.add_column(Column(DZ_stat_shift,name='DZ_STAT'))
    if 'Z_noRSD' in metadata.dtype.names:
        meta.add_column(Column(metadata['Z_noRSD'],name='Z_NORSD'))
    else:
        log.info('Z_noRSD field not present in transmission file. Z_NORSD not saved to truth file')

    hdu = pyfits.convenience.table_to_hdu(meta)
    hdu.header['EXTNAME'] = 'TRUTH'
    hduqso=pyfits.convenience.table_to_hdu(qsometa)
    hduqso.header['EXTNAME'] = 'QSO_META'
    hdulist=pyfits.HDUList([pyfits.PrimaryHDU(),hdu,hduqso])
    if args.dla:
        hdulist.append(hdu_dla)
    if args.balprob:
        hdulist.append(hdu_bal)
    hdulist.writeto(truth_filename, overwrite=True)
    hdulist.close()




    if args.zbest :
        log.info("Read fibermap")
        fibermap = read_fibermap(ofilename)
        log.info("Writing a zbest file {}".format(zbest_filename))
        columns = [
            ('CHI2', 'f8'),
            ('COEFF', 'f8' , (4,)),
            ('Z', 'f8'),
            ('ZERR', 'f8'),
            ('ZWARN', 'i8'),
            ('SPECTYPE', (str,96)),
            ('SUBTYPE', (str,16)),
            ('TARGETID', 'i8'),
            ('DELTACHI2', 'f8'),
            ('BRICKNAME', (str,8))]
        zbest = Table(np.zeros(nqso, dtype=columns))
        zbest['CHI2'][:] = 0.
        zbest['Z'][:] = metadata['Z']
        zbest['ZERR'][:] = 0.
        zbest['ZWARN'][:] = 0
        zbest['SPECTYPE'][:] = 'QSO'
        zbest['SUBTYPE'][:] = ''
        zbest['TARGETID'][:] = metadata['MOCKID']
        zbest['DELTACHI2'][:] = 25.
        hzbest = pyfits.convenience.table_to_hdu(zbest); hzbest.name='ZBEST'
        hfmap  = pyfits.convenience.table_to_hdu(fibermap);  hfmap.name='FIBERMAP'
        hdulist =pyfits.HDUList([pyfits.PrimaryHDU(),hzbest,hfmap])
        hdulist.writeto(zbest_filename, overwrite=True)
        hdulist.close() # see if this helps with memory issue
Exemple #4
0
def dust_transmission(wave,ebv) :
    Rv = 3.1
    extinction = ext_odonnell(wave,Rv=Rv)
    return 10**(-Rv*extinction*ebv/2.5)
Exemple #5
0
def dust_transmission(wave, ebv):
    Rv = 3.1
    extinction = ext_odonnell(wave, Rv=Rv)
    return 10**(-Rv * extinction * ebv / 2.5)