示例#1
0
def qa_skysub(param, frame, skymodel, quick_look=False):
    """Calculate QA on SkySubtraction

    Note: Pixels rejected in generating the SkyModel (as above), are
    not rejected in the stats calculated here.  Would need to carry
    along current_ivar to do so.

    Args:
        param : dict of QA parameters
        frame : desispec.Frame object
        skymodel : desispec.SkyModel object
        quick_look : bool, optional
          If True, do QuickLook specific QA (or avoid some)
    Returns:
        qadict: dict of QA outputs
          Need to record simple Python objects for yaml (str, float, int)
    """
    log = get_logger()

    # Output dict
    qadict = {}
    qadict['NREJ'] = int(skymodel.nrej)

    # Grab sky fibers on this frame
    skyfibers = np.where(frame.fibermap['OBJTYPE'] == 'SKY')[0]
    assert np.max(skyfibers) < 500  #- indices, not fiber numbers
    nfibers = len(skyfibers)
    qadict['NSKY_FIB'] = int(nfibers)

    current_ivar = frame.ivar[skyfibers].copy()
    flux = frame.flux[skyfibers]

    # Subtract
    res = flux - skymodel.flux[skyfibers]  # Residuals
    res_ivar = util.combine_ivar(current_ivar, skymodel.ivar[skyfibers])

    # Chi^2 and Probability
    chi2_fiber = np.sum(res_ivar * (res**2), 1)
    chi2_prob = np.zeros(nfibers)
    for ii in range(nfibers):
        # Stats
        dof = np.sum(res_ivar[ii, :] > 0.)
        chi2_prob[ii] = scipy.stats.chisqprob(chi2_fiber[ii], dof)
    # Bad models
    qadict['NBAD_PCHI'] = int(np.sum(chi2_prob < param['PCHI_RESID']))
    if qadict['NBAD_PCHI'] > 0:
        log.warn("Bad Sky Subtraction in {:d} fibers".format(
            qadict['NBAD_PCHI']))

    # Median residual
    qadict['MED_RESID'] = float(np.median(res))  # Median residual (counts)
    log.info("Median residual for sky fibers = {:g}".format(
        qadict['MED_RESID']))

    # Residual percentiles
    perc = dustat.perc(res, per=param['PER_RESID'])
    qadict['RESID_PER'] = [float(iperc) for iperc in perc]

    # Mean Sky Continuum from all skyfibers
    # need to limit in wavelength?

    if quick_look:
        continuum = scipy.ndimage.filters.median_filter(
            flux, 200)  # taking 200 bins (somewhat arbitrarily)
        mean_continuum = np.zeros(flux.shape[1])
        for ii in range(flux.shape[1]):
            mean_continuum[ii] = np.mean(continuum[:, ii])
        qadict['MEAN_CONTIN'] = mean_continuum

    # Median Signal to Noise on sky subtracted spectra
    # first do the subtraction:
    if quick_look:
        fframe = frame  # make a copy
        sskymodel = skymodel  # make a copy
        subtract_sky(fframe, sskymodel)
        medsnr = np.zeros(fframe.flux.shape[0])
        totsnr = np.zeros(fframe.flux.shape[0])
        for ii in range(fframe.flux.shape[0]):
            signalmask = fframe.flux[ii, :] > 0
            # total snr considering bin by bin uncorrelated S/N
            snr = fframe.flux[ii, signalmask] * np.sqrt(
                fframe.ivar[ii, signalmask])
            medsnr[ii] = np.median(snr)
            totsnr[ii] = np.sqrt(np.sum(snr**2))
        qadict['MED_SNR'] = medsnr  # for each fiber
        qadict['TOT_SNR'] = totsnr  # for each fiber

    # Return
    return qadict
示例#2
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def sky_resid(param, frame, skymodel, quick_look=False):
    """ QA Algorithm for sky residual
    To be called from desispec.sky.qa_skysub and desispec.qa.qa_quicklook.Sky_residual.run_qa
    Args:
        param : dict of QA parameters
        frame : desispec.Frame object after sky subtraction
        skymodel : desispec.SkyModel object
    Returns a qa dictionary for sky resid
    """
    # Output dict
    qadict = {}
    qadict['NREJ'] = int(skymodel.nrej)

    if quick_look:
        qadict['RA'] = frame.fibermap['RA_TARGET']
        qadict['DEC'] = frame.fibermap['DEC_TARGET']

    # Grab sky fibers on this frame
    skyfibers = np.where(frame.fibermap['OBJTYPE'] == 'SKY')[0]
    assert np.max(skyfibers) < 500  #- indices, not fiber numbers
    nfibers = len(skyfibers)
    qadict['NSKY_FIB'] = int(nfibers)

    #current_ivar=frame.ivar[skyfibers].copy()
    #flux = frame.flux[skyfibers]

    # Record median flux
    qadict['MED_SKY'] = np.median(skymodel.flux[skyfibers])  # Counts

    #- Residuals
    res = frame.flux[skyfibers]  #- as this frame is already sky subtracted
    res_ivar = frame.ivar[skyfibers]

    # Chi^2 and Probability
    chi2_fiber = np.sum(res_ivar * (res**2), 1)
    chi2_prob = np.zeros(nfibers)
    for ii in range(nfibers):
        # Stats
        dof = np.sum(res_ivar[ii, :] > 0.)
        chi2_prob[ii] = scipy.stats.chisqprob(chi2_fiber[ii], dof)
    # Bad models
    qadict['NBAD_PCHI'] = int(np.sum(chi2_prob < param['PCHI_RESID']))
    if qadict['NBAD_PCHI'] > 0:
        log.warning("Bad Sky Subtraction in {:d} fibers".format(
            qadict['NBAD_PCHI']))
    # Median residual
    qadict['MED_RESID'] = float(np.median(res))  # Median residual (counts)
    log.info("Median residual for sky fibers = {:g}".format(
        qadict['MED_RESID']))

    # Residual percentiles
    perc = dustat.perc(res, per=param['PER_RESID'])
    qadict['RESID_PER'] = [float(iperc) for iperc in perc]

    qadict['RESID_RMS'] = []

    qadict["SKY_FIBERID"] = skyfibers.tolist()
    #- Residuals in wave and fiber axes
    if quick_look:
        qadict["MED_RESID_WAVE"] = np.median(res, axis=0)
        qadict["MED_RESID_FIBER"] = np.median(res, axis=1)
        #- Weighted average for each bin on all fibers
        qadict["WAVG_RES_WAVE"] = np.sum(res * res_ivar, 0) / np.sum(
            res_ivar, 0)

    #- Histograms for residual/sigma #- inherited from qa_plots.frame_skyres()
    if quick_look:
        binsz = param['BIN_SZ']
        gd_res = res_ivar > 0.
        devs = res[gd_res] * np.sqrt(res_ivar[gd_res])
        i0, i1 = int(np.min(devs) / binsz) - 1, int(np.max(devs) / binsz) + 1
        rng = tuple(binsz * np.array([i0, i1]))
        nbin = i1 - i0
        hist, edges = np.histogram(devs, range=rng, bins=nbin)

        qadict['DEVS_1D'] = hist.tolist()  #- histograms for deviates
        qadict['DEVS_EDGES'] = edges.tolist()  #- Bin edges

    #- Add additional metrics for quicklook
    if quick_look:
        qadict["WAVELENGTH"] = frame.wave
    # Return
    return qadict
示例#3
0
文件: sky.py 项目: rstaten/desispec
def qa_skysub(param, frame, skymodel, quick_look=False):
    """Calculate QA on SkySubtraction

    Note: Pixels rejected in generating the SkyModel (as above), are
    not rejected in the stats calculated here.  Would need to carry
    along current_ivar to do so.

    Args:
        param : dict of QA parameters
        frame : desispec.Frame object
        skymodel : desispec.SkyModel object
        quick_look : bool, optional
          If True, do QuickLook specific QA (or avoid some)
    Returns:
        qadict: dict of QA outputs
          Need to record simple Python objects for yaml (str, float, int)
    """
    log=get_logger()

    # Output dict
    qadict = {}
    qadict['NREJ'] = int(skymodel.nrej)

    # Grab sky fibers on this frame
    skyfibers = np.where(frame.fibermap['OBJTYPE'] == 'SKY')[0]
    assert np.max(skyfibers) < 500  #- indices, not fiber numbers
    nfibers=len(skyfibers)
    qadict['NSKY_FIB'] = int(nfibers)

    current_ivar=frame.ivar[skyfibers].copy()
    flux = frame.flux[skyfibers]

    # Subtract
    res = flux - skymodel.flux[skyfibers] # Residuals
    res_ivar = util.combine_ivar(current_ivar, skymodel.ivar[skyfibers])

    # Chi^2 and Probability
    chi2_fiber = np.sum(res_ivar*(res**2),1)
    chi2_prob = np.zeros(nfibers)
    for ii in range(nfibers):
        # Stats
        dof = np.sum(res_ivar[ii,:] > 0.)
        chi2_prob[ii] = scipy.stats.chisqprob(chi2_fiber[ii], dof)
    # Bad models
    qadict['NBAD_PCHI'] = int(np.sum(chi2_prob < param['PCHI_RESID']))
    if qadict['NBAD_PCHI'] > 0:
        log.warn("Bad Sky Subtraction in {:d} fibers".format(
                qadict['NBAD_PCHI']))

    # Median residual
    qadict['MED_RESID'] = float(np.median(res)) # Median residual (counts)
    log.info("Median residual for sky fibers = {:g}".format(
        qadict['MED_RESID']))

    # Residual percentiles
    perc = dustat.perc(res, per=param['PER_RESID'])
    qadict['RESID_PER'] = [float(iperc) for iperc in perc]

    # Mean Sky Continuum from all skyfibers
    # need to limit in wavelength?

    if quick_look:
        continuum=scipy.ndimage.filters.median_filter(flux,200) # taking 200 bins (somewhat arbitrarily)
        mean_continuum=np.zeros(flux.shape[1])
        for ii in range(flux.shape[1]):
            mean_continuum[ii]=np.mean(continuum[:,ii])
        qadict['MEAN_CONTIN'] = mean_continuum

    # Median Signal to Noise on sky subtracted spectra
    # first do the subtraction:
    if quick_look:
        fframe=frame # make a copy
        sskymodel=skymodel # make a copy
        subtract_sky(fframe,sskymodel)
        medsnr=np.zeros(fframe.flux.shape[0])
        totsnr=np.zeros(fframe.flux.shape[0])
        for ii in range(fframe.flux.shape[0]):
            signalmask=fframe.flux[ii,:]>0
            # total snr considering bin by bin uncorrelated S/N
            snr=fframe.flux[ii,signalmask]*np.sqrt(fframe.ivar[ii,signalmask])
            medsnr[ii]=np.median(snr)
            totsnr[ii]=np.sqrt(np.sum(snr**2))
        qadict['MED_SNR']=medsnr  # for each fiber
        qadict['TOT_SNR']=totsnr  # for each fiber

    # Return
    return qadict
示例#4
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def desi_qso_templates(z_wind=0.2, zmnx=(0.4,4.), outfil=None, N_perz=500,
                       boss_pca_fil=None, wvmnx=(3500., 10000.),
                       rebin_wave=None, rstate=None,
                       sdss_pca_fil=None, no_write=False, redshift=None,
                       seed=None, old_read=False, ipad=40, cosmo=None):
    """ Generate QSO templates for DESI

    Rebins to input wavelength array (or log10 in wvmnx)

    Parameters
    ----------
    z_wind : float, optional
      Window for sampling PCAs
    zmnx : tuple, optional
      Min/max for generation
    N_perz : int, optional
      Number of draws per redshift window
    old_read : bool, optional
      Read the files the old way
    seed : int, optional
      Seed for the random number state
    rebin_wave : ndarray, optional
      Input wavelengths for rebinning
    wvmnx : tuple, optional
      Wavelength limits for rebinning (not used with rebin_wave)
    redshift : ndarray, optional
      Redshifts desired for the templates
    ipad : int, optional
      Padding for enabling enough models
    cosmo: astropy.cosmology.core, optional
       Cosmology inistantiation from astropy.cosmology.code
    Returns
    -------
    wave : ndarray
      Wavelengths that the spectra were rebinned to
    flux : ndarray (2D; flux vs. model)
    z : ndarray
      Redshifts
    """


    # Cosmology
    if cosmo is None:
        from astropy import cosmology
        cosmo = cosmology.core.FlatLambdaCDM(70., 0.3)

    if old_read:
        # PCA values
        if boss_pca_fil is None:
            boss_pca_fil = 'BOSS_DR10Lya_PCA_values_nocut.fits.gz'
        hdu = fits.open(boss_pca_fil)
        boss_pca_coeff = hdu[1].data

        if sdss_pca_fil is None:
            sdss_pca_fil = 'SDSS_DR7Lya_PCA_values_nocut.fits.gz'
        hdu2 = fits.open(sdss_pca_fil)
        sdss_pca_coeff = hdu2[1].data

        # Open the BOSS catalog file
        boss_cat_fil = os.environ.get('BOSSPATH')+'/DR10/BOSSLyaDR10_cat_v2.1.fits.gz'
        bcat_hdu = fits.open(boss_cat_fil)
        t_boss = bcat_hdu[1].data
        boss_zQSO = t_boss['z_pipe']

        # Open the SDSS catalog file
        sdss_cat_fil = os.environ.get('SDSSPATH')+'/DR7_QSO/dr7_qso.fits.gz'
        scat_hdu = fits.open(sdss_cat_fil)
        t_sdss = scat_hdu[1].data
        sdss_zQSO = t_sdss['z']
        if len(sdss_pca_coeff) != len(sdss_zQSO):
            print('Need to finish running the SDSS models!')
            sdss_zQSO = sdss_zQSO[0:len(sdss_pca_coeff)]
        # Eigenvectors
        eigen, eigen_wave = fbq.read_qso_eigen()
    else:
        infile = desisim.io.find_basis_template('qso')
        with fits.open(infile) as hdus:
            hdu_names = [hdus[ii].name for ii in range(len(hdus))]
            boss_pca_coeff = hdus[hdu_names.index('BOSS_PCA')].data
            sdss_pca_coeff = hdus[hdu_names.index('SDSS_PCA')].data
            boss_zQSO = hdus[hdu_names.index('BOSS_Z')].data
            sdss_zQSO = hdus[hdu_names.index('SDSS_Z')].data
            eigen = hdus[hdu_names.index('SDSS_EIGEN')].data
            eigen_wave = hdus[hdu_names.index('SDSS_EIGEN_WAVE')].data

    # Fiddle with the eigen-vectors
    npix = len(eigen_wave)
    chkpix = np.where((eigen_wave > 900.) & (eigen_wave < 5000.) )[0]
    lambda_912 = 911.76
    pix912 = np.argmin( np.abs(eigen_wave-lambda_912) )

    # Loop on redshift.  If the
    if redshift is None:
        z0 = np.arange(zmnx[0],zmnx[1],z_wind)
        z1 = z0 + z_wind
    else:
        if np.isscalar(redshift):
            z0 = np.array([redshift])
        else:
            z0 = redshift.copy()
        z1 = z0.copy() #+ z_wind


    pca_list = ['PCA0', 'PCA1', 'PCA2', 'PCA3']
    PCA_mean = np.zeros(4)
    PCA_sig = np.zeros(4)
    PCA_rand = np.zeros((4,N_perz*ipad))

    final_spec = np.zeros((npix, N_perz * len(z0)))
    final_wave = np.zeros((npix, N_perz * len(z0)))
    final_z = np.zeros(N_perz * len(z0))

    # Random state
    if rstate is None:
        rstate = np.random.RandomState(seed)

    for ii in range(len(z0)):

        # BOSS or SDSS?
        if z0[ii] > 2.15:
            zQSO = boss_zQSO
            pca_coeff = boss_pca_coeff
        else:
            zQSO = sdss_zQSO
            pca_coeff = sdss_pca_coeff

        # Random z values and wavelengths
        zrand = rstate.uniform( z0[ii], z1[ii], N_perz*ipad)
        wave = np.outer(eigen_wave, 1+zrand)

        # MFP (Worseck+14)
        mfp = 37. * ( (1+zrand)/5. )**(-5.4) # Physical Mpc

        # Grab PCA mean + sigma
        if redshift is None:
            idx = np.where( (zQSO >= z0[ii]) & (zQSO < z1[ii]) )[0]
        else:
            # Hack by @moustakas: add a little jitter to get the set of QSOs
            # that are *nearest* in redshift to the desired output redshift.
            idx = np.where( (zQSO >= z0[ii]-0.01) & (zQSO < z1[ii]+0.01) )[0]
            if len(idx) == 0:
                idx = np.array([(np.abs(zQSO-zrand[0])).argmin()])
                #pdb.set_trace()
        log.debug('Making z=({:g},{:g}) with {:d} input quasars'.format(z0[ii],z1[ii],len(idx)))

        # Get PCA stats and random values
        for jj,ipca in enumerate(pca_list):
            if jj == 0:  # Use bounds for PCA0 [avoids negative values]
                xmnx = perc(pca_coeff[ipca][idx], per=95)
                PCA_rand[jj, :] = rstate.uniform(xmnx[0], xmnx[1], N_perz*ipad)
            else:
                PCA_mean[jj] = np.mean(pca_coeff[ipca][idx])
                PCA_sig[jj] = np.std(pca_coeff[ipca][idx])
                # Draws
                PCA_rand[jj, :] = rstate.uniform( PCA_mean[jj] - 2*PCA_sig[jj],
                                        PCA_mean[jj] + 2*PCA_sig[jj], N_perz*ipad)

        # Generate the templates (ipad*N_perz)
        spec = np.dot(eigen.T, PCA_rand)

        # Take first good N_perz

        # Truncate, MFP, Fill
        ngd = 0
        nbad = 0
        for kk in range(ipad*N_perz):
            # Any zero values?
            mn = np.min(spec[chkpix, kk])
            if mn < 0.:
                nbad += 1
                continue

            # MFP
            if z0[ii] > 2.39:
                z912 = wave[0:pix912,kk]/lambda_912 - 1.
                phys_dist = np.fabs( cosmo.lookback_distance(z912) -
                                cosmo.lookback_distance(zrand[kk]) ) # Mpc
                spec[0:pix912, kk] = spec[0:pix912,kk] * np.exp(-phys_dist.value/mfp[kk])

            # Write
            final_spec[:, ii*N_perz+ngd] = spec[:,kk]
            final_wave[:, ii*N_perz+ngd] = wave[:,kk]
            final_z[ii*N_perz+ngd] = zrand[kk]
            ngd += 1
            if ngd == N_perz:
                break
        if ngd != N_perz:
            print('Did not make enough!')
            #pdb.set_trace()
            log.warning('Did not make enough qso templates. ngd = {}, N_perz = {}'.format(ngd,N_perz))

    # Rebin
    if rebin_wave is None:
        light = C_LIGHT        # [km/s]
        velpixsize = 10.            # [km/s]
        pixsize = velpixsize/light/np.log(10) # [pixel size in log-10 A]
        minwave = np.log10(wvmnx[0])          # minimum wavelength [log10-A]
        maxwave = np.log10(wvmnx[1])          # maximum wavelength [log10-A]
        r_npix = np.round((maxwave-minwave)/pixsize+1)

        log_wave = minwave+np.arange(r_npix)*pixsize # constant log-10 spacing
    else:
        log_wave = np.log10(rebin_wave)
        r_npix = len(log_wave)

    totN = N_perz * len(z0)
    rebin_spec = np.zeros((r_npix, totN))


    for ii in range(totN):
        # Interpolate (in log space)
        rebin_spec[:, ii] = resample_flux(log_wave, np.log10(final_wave[:, ii]), final_spec[:, ii])
        #f1d = interp1d(np.log10(final_wave[:,ii]), final_spec[:,ii])
        #rebin_spec[:,ii] = f1d(log_wave)

    if outfil is None:
        return 10.**log_wave, rebin_spec, final_z

    # Transpose for consistency
    out_spec = np.array(rebin_spec.T, dtype='float32')

    # Write
    hdu = fits.PrimaryHDU(out_spec)
    hdu.header.set('PROJECT', 'DESI QSO TEMPLATES')
    hdu.header.set('VERSION', '1.1')
    hdu.header.set('OBJTYPE', 'QSO')
    hdu.header.set('DISPAXIS',  1, 'dispersion axis')
    hdu.header.set('CRPIX1',  1, 'reference pixel number')
    hdu.header.set('CRVAL1',  minwave, 'reference log10(Ang)')
    hdu.header.set('CDELT1',  pixsize, 'delta log10(Ang)')
    hdu.header.set('LOGLAM',  1, 'log10 spaced wavelengths?')
    hdu.header.set('AIRORVAC', 'vac', ' wavelengths in vacuum (vac) or air')
    hdu.header.set('VELSCALE', velpixsize, ' pixel size in km/s')
    hdu.header.set('WAVEUNIT', 'Angstrom', ' wavelength units')
    hdu.header.set('BUNIT', '1e-17 erg/s/cm2/A', ' flux unit')

    idval = list(range(totN))
    col0 = fits.Column(name=str('TEMPLATEID'),format=str('J'), array=idval)
    col1 = fits.Column(name=str('Z'),format=str('E'),array=final_z)
    cols = fits.ColDefs([col0, col1])
    tbhdu = fits.BinTableHDU.from_columns(cols)
    tbhdu.header.set('EXTNAME','METADATA')

    hdulist = fits.HDUList([hdu, tbhdu])
    hdulist.writeto(outfil, overwrite=True)

    return final_wave, final_spec, final_z
示例#5
0
def qa_skysub(param, frame, skymodel, quick_look=False):
    """Calculate QA on SkySubtraction

    Note: Pixels rejected in generating the SkyModel (as above), are
    not rejected in the stats calculated here.  Would need to carry
    along current_ivar to do so.

    Args:
        param : dict of QA parameters
        frame : desispec.Frame object
        skymodel : desispec.SkyModel object
        quick_look : bool, optional
          If True, do QuickLook specific QA (or avoid some)
    Returns:
        qadict: dict of QA outputs
          Need to record simple Python objects for yaml (str, float, int)
    """
    log = get_logger()

    # Output dict
    qadict = {}
    qadict['NREJ'] = int(skymodel.nrej)

    # Grab sky fibers on this frame
    skyfibers = np.where(frame.fibermap['OBJTYPE'] == 'SKY')[0]
    assert np.max(skyfibers) < 500  #- indices, not fiber numbers
    nfibers = len(skyfibers)
    qadict['NSKY_FIB'] = int(nfibers)

    current_ivar = frame.ivar[skyfibers].copy()
    flux = frame.flux[skyfibers]

    # Subtract
    res = flux - skymodel.flux[skyfibers]  # Residuals
    res_ivar = util.combine_ivar(current_ivar, skymodel.ivar[skyfibers])

    # Chi^2 and Probability
    chi2_fiber = np.sum(res_ivar * (res**2), 1)
    chi2_prob = np.zeros(nfibers)
    for ii in range(nfibers):
        # Stats
        dof = np.sum(res_ivar[ii, :] > 0.)
        chi2_prob[ii] = scipy.stats.chisqprob(chi2_fiber[ii], dof)
    # Bad models
    qadict['NBAD_PCHI'] = int(np.sum(chi2_prob < param['PCHI_RESID']))
    if qadict['NBAD_PCHI'] > 0:
        log.warning("Bad Sky Subtraction in {:d} fibers".format(
            qadict['NBAD_PCHI']))

    # Median residual
    qadict['MED_RESID'] = float(np.median(res))  # Median residual (counts)
    log.info("Median residual for sky fibers = {:g}".format(
        qadict['MED_RESID']))

    # Residual percentiles
    perc = dustat.perc(res, per=param['PER_RESID'])
    qadict['RESID_PER'] = [float(iperc) for iperc in perc]

    #- Add per fiber median residuals
    qadict["MED_RESID_FIBER"] = np.median(res, axis=1)

    #- Evaluate residuals in wave axis for quicklook
    if quick_look:

        qadict["MED_RESID_WAVE"] = np.median(res, axis=0)
        qadict["WAVELENGTH"] = frame.wave

    # Return
    return qadict