コード例 #1
0
 def setUp(self):
     self.nspec = 5
     self.nwave = 10
     self.wave = np.arange(self.nwave)
     self.fiberflat = np.random.uniform(size=(self.nspec, self.nwave))
     self.ivar = np.ones(self.fiberflat.shape)
     self.mask = np.zeros(self.fiberflat.shape, dtype=np.uint32)
     self.meanspec = np.random.uniform(size=self.nwave)
     self.ff = FiberFlat(self.wave, self.fiberflat, self.ivar, self.mask,
                         self.meanspec)
コード例 #2
0
    def run_pa(self, frame, outputfile):
        from lvmspec.fiberflat import FiberFlat
        import lvmspec.io.fiberflat as ffIO
        from lvmspec.linalg import cholesky_solve
        nwave = frame.nwave
        nfibers = frame.nspec
        wave = frame.wave  #- this will become part of output too
        flux = frame.flux
        sumFlux = np.zeros((nwave))
        realFlux = np.zeros(flux.shape)
        ivar = frame.ivar * (frame.mask == 0)
        #deconv
        for fib in range(nfibers):
            Rf = frame.R[fib].todense()
            B = flux[fib]
            realFlux[fib] = cholesky_solve(Rf, B)
            sumFlux += realFlux[fib]
        #iflux=nfibers/sumFlux
        flat = np.zeros(flux.shape)
        flat_ivar = np.zeros(ivar.shape)
        avg = sumFlux / nfibers
        for fib in range(nfibers):
            Rf = frame.R[fib]
            # apply and reconvolute
            M = Rf.dot(avg)
            M0 = (M == 0)
            flat[fib] = (~M0) * flux[fib] / (M + M0) + M0
            flat_ivar[fib] = ivar[fib] * M**2
        fibflat = FiberFlat(frame.wave.copy(), flat, flat_ivar,
                            frame.mask.copy(), avg)

        #fiberflat=compute_fiberflat(input_frame)
        ffIO.write_fiberflat(outputfile, fibflat, header=frame.meta)
        log.info("Wrote fiberflat file {}".format(outputfile))
コード例 #3
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ファイル: test_binscripts.py プロジェクト: sdss/lvmspec
 def _write_fiberflat(self):
     """Write a fake fiberflat"""
     fiberflat = np.ones((self.nspec, self.nwave))
     ivar = np.ones((self.nspec, self.nwave))
     mask = np.zeros((self.nspec, self.nwave), dtype=int)
     meanspec = np.ones(self.nwave)
     ff = FiberFlat(self.wave, fiberflat, ivar, mask, meanspec)
     io.write_fiberflat(self.fiberflatfile, ff)
コード例 #4
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def get_fiberflat_from_frame(frame):
    from lvmspec.fiberflat import FiberFlat
    flux = frame.flux
    fiberflat = np.ones_like(flux)
    ffivar = 2 * np.ones_like(flux)
    fiberflat[0] *= 0.8
    fiberflat[1] *= 1.2
    ff = FiberFlat(frame.wave, fiberflat, ffivar)
    return ff
コード例 #5
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    def test_apply_fiberflat_ivar(self):
        '''test error propagation in apply_fiberflat'''
        wave = np.arange(5000, 5010)
        nwave = len(wave)
        nspec = 3
        flux = np.random.uniform(0.9, 1.0, size=(nspec, nwave))
        ivar = np.ones_like(flux)
        origframe = Frame(wave, flux, ivar, spectrograph=0)

        fiberflat = np.ones_like(flux)
        ffmask = np.zeros_like(flux)
        fiberflat[0] *= 0.5
        fiberflat[1] *= 1.5

        #- ff with essentially no error
        ffivar = 1e20 * np.ones_like(flux)
        ff = FiberFlat(wave, fiberflat, ffivar)
        frame = copy.deepcopy(origframe)
        apply_fiberflat(frame, ff)
        self.assertTrue(np.allclose(frame.ivar, fiberflat**2))

        #- ff with large error
        ffivar = np.ones_like(flux)
        ff = FiberFlat(wave, fiberflat, ffivar)
        frame = copy.deepcopy(origframe)
        apply_fiberflat(frame, ff)

        #- c = a/b
        #- (sigma_c/c)^2 = (sigma_a/a)^2 + (sigma_b/b)^2
        var = frame.flux**2 * (1.0/(origframe.ivar * origframe.flux**2) + \
                               1.0/(ff.ivar * ff.fiberflat**2))
        self.assertTrue(np.allclose(frame.ivar, 1 / var))

        #- ff.ivar=0 should result in frame.ivar=0, even if ff.fiberflat=0 too
        ffivar = np.ones_like(flux)
        ffivar[0, 0:5] = 0.0
        fiberflat[0, 0:5] = 0.0
        ff = FiberFlat(wave, fiberflat, ffivar)
        frame = copy.deepcopy(origframe)
        apply_fiberflat(frame, ff)

        self.assertTrue(np.all(frame.ivar[0, 0:5] == 0.0))
コード例 #6
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    def test_dimensions(self):
        #- check dimensionality mismatches
        with self.assertRaises(ValueError):
            FiberFlat(self.wave, self.wave, self.ivar, self.mask,
                      self.meanspec)

        with self.assertRaises(ValueError):
            FiberFlat(self.wave, self.wave, self.ivar, self.mask,
                      self.meanspec)

        with self.assertRaises(ValueError):
            FiberFlat(self.wave, self.fiberflat, self.ivar, self.mask,
                      self.fiberflat)

        with self.assertRaises(ValueError):
            FiberFlat(self.wave, self.fiberflat[0:2], self.ivar, self.mask,
                      self.meanspec)

        with self.assertRaises(ValueError):
            FiberFlat(self.fiberflat, self.fiberflat, self.ivar, self.mask,
                      self.meanspec)

        with self.assertRaises(ValueError):
            FiberFlat(self.wave, self.fiberflat, self.wave, self.mask,
                      self.meanspec)

        with self.assertRaises(ValueError):
            FiberFlat(self.wave, self.fiberflat, self.ivar, self.mask[0:2, :],
                      self.meanspec)

        fibers = np.arange(self.nspec)
        FiberFlat(self.wave,
                  self.fiberflat,
                  self.ivar,
                  self.mask,
                  self.meanspec,
                  fibers=fibers)
        with self.assertRaises(ValueError):
            FiberFlat(self.wave,
                      self.fiberflat,
                      self.ivar,
                      self.mask,
                      self.meanspec,
                      fibers=fibers[1:])
コード例 #7
0
    def test_apply_fiberflat(self):
        '''test apply_fiberflat interface and changes to flux and mask'''
        wave = np.arange(5000, 5050)
        nwave = len(wave)
        nspec = 3
        flux = np.random.uniform(size=(nspec, nwave))
        ivar = np.ones_like(flux)
        frame = Frame(wave, flux, ivar, spectrograph=0)

        fiberflat = np.ones_like(flux)
        ffivar = 2 * np.ones_like(flux)
        ffmask = np.zeros_like(flux)
        fiberflat[0] *= 0.8
        fiberflat[1] *= 1.2
        fiberflat[2, 0:10] = 0  #- bad fiberflat
        ffivar[2, 10:20] = 0  #- bad fiberflat
        ffmask[2, 20:30] = 1  #- bad fiberflat

        ff = FiberFlat(wave, fiberflat, ffivar)

        origframe = copy.deepcopy(frame)
        apply_fiberflat(frame, ff)

        #- was fiberflat applied?
        self.assertTrue(np.all(frame.flux[0] == origframe.flux[0] / 0.8))
        self.assertTrue(np.all(frame.flux[1] == origframe.flux[1] / 1.2))
        self.assertTrue(np.all(frame.flux[2] == origframe.flux[2]))

        #- did mask get set?
        ii = (ff.fiberflat == 0)
        self.assertTrue(np.all((frame.mask[ii] & specmask.BADFIBERFLAT) != 0))
        ii = (ff.ivar == 0)
        self.assertTrue(np.all((frame.mask[ii] & specmask.BADFIBERFLAT) != 0))
        ii = (ff.mask != 0)
        self.assertTrue(np.all((frame.mask[ii] & specmask.BADFIBERFLAT) != 0))

        #- Should fail if frame and ff don't have a common wavelength grid
        frame.wave = frame.wave + 0.1
        with self.assertRaises(ValueError):
            apply_fiberflat(frame, ff)
コード例 #8
0
def main(args):

    # Set up the logger
    if args.verbose:
        log = get_logger(DEBUG)
    else:
        log = get_logger()

    # Make sure all necessary environment variables are set
    setup_envs()

    # Initialize random number generator to use.
    np.random.seed(args.seed)
    random_state = np.random.RandomState(args.seed)

    # Derive spectrograph number from nstart if needed
    if args.spectrograph is None:
        args.spectrograph = args.nstart / args.n_fibers

    # Read fibermapfile to get object type, night and expid
    fibermap, objtype, night, expid = get_fibermap(args.fibermap,
                                                   log=log,
                                                   nspec=args.nspec)

    # Initialize the spectral simulator
    log.info("Initializing SpecSim with config {}".format(args.config))
    lvmparams = load_lvmparams(config=args.config, telescope=args.telescope)
    qsim = get_simulator(args.config, num_fibers=1, params=lvmparams)

    if args.simspec:
        # Read the input file
        log.info('Reading input file {}'.format(args.simspec))
        simspec = lvmsim.io.read_simspec(args.simspec)
        nspec = simspec.nspec
        if simspec.flavor == 'arc':
            # - TODO: do we need quickgen to support arcs?  For full pipeline
            # - arcs are used to measure PSF but aren't extracted except for
            # - debugging.
            # - TODO: if we do need arcs, this needs to be redone.
            # - conversion from phot to flux doesn't include throughput,
            # - and arc lines are rebinned to nearest 0.2 A.

            # Create full wavelength and flux arrays for arc exposure
            wave_b = np.array(simspec.wave['b'])
            wave_r = np.array(simspec.wave['r'])
            wave_z = np.array(simspec.wave['z'])
            phot_b = np.array(simspec.phot['b'][0])
            phot_r = np.array(simspec.phot['r'][0])
            phot_z = np.array(simspec.phot['z'][0])
            sim_wave = np.concatenate((wave_b, wave_r, wave_z))
            sim_phot = np.concatenate((phot_b, phot_r, phot_z))
            wavelengths = np.arange(3533., 9913.1, 0.2)
            phot = np.zeros(len(wavelengths))
            for i in range(len(sim_wave)):
                wavelength = sim_wave[i]
                flux_index = np.argmin(abs(wavelength - wavelengths))
                phot[flux_index] = sim_phot[i]
            # Convert photons to flux: following specter conversion method
            dw = np.gradient(wavelengths)
            exptime = 5.  # typical BOSS exposure time in s
            fibarea = const.pi * (1.07e-2 /
                                  2)**2  # cross-sectional fiber area in cm^2
            hc = 1.e17 * const.h * const.c  # convert to erg A
            spectra = (hc * exptime * fibarea * dw * phot) / wavelengths
        else:
            wavelengths = simspec.wave['brz']
            spectra = simspec.flux
        if nspec < args.nspec:
            log.info("Only {} spectra in input file".format(nspec))
            args.nspec = nspec

    else:
        # Initialize the output truth table.
        spectra = []
        wavelengths = qsim.source.wavelength_out.to(u.Angstrom).value
        npix = len(wavelengths)
        truth = dict()
        meta = Table()
        truth['OBJTYPE'] = np.zeros(args.nspec, dtype=(str, 10))
        truth['FLUX'] = np.zeros((args.nspec, npix))
        truth['WAVE'] = wavelengths
        jj = list()

        for thisobj in set(true_objtype):
            ii = np.where(true_objtype == thisobj)[0]
            nobj = len(ii)
            truth['OBJTYPE'][ii] = thisobj
            log.info('Generating {} template'.format(thisobj))

            # Generate the templates
            if thisobj == 'ELG':
                elg = lvmsim.templates.ELG(wave=wavelengths,
                                           add_SNeIa=args.add_SNeIa)
                flux, tmpwave, meta1 = elg.make_templates(
                    nmodel=nobj,
                    seed=args.seed,
                    zrange=args.zrange_elg,
                    sne_rfluxratiorange=args.sne_rfluxratiorange)
            elif thisobj == 'LRG':
                lrg = lvmsim.templates.LRG(wave=wavelengths,
                                           add_SNeIa=args.add_SNeIa)
                flux, tmpwave, meta1 = lrg.make_templates(
                    nmodel=nobj,
                    seed=args.seed,
                    zrange=args.zrange_lrg,
                    sne_rfluxratiorange=args.sne_rfluxratiorange)
            elif thisobj == 'QSO':
                qso = lvmsim.templates.QSO(wave=wavelengths)
                flux, tmpwave, meta1 = qso.make_templates(
                    nmodel=nobj, seed=args.seed, zrange=args.zrange_qso)
            elif thisobj == 'BGS':
                bgs = lvmsim.templates.BGS(wave=wavelengths,
                                           add_SNeIa=args.add_SNeIa)
                flux, tmpwave, meta1 = bgs.make_templates(
                    nmodel=nobj,
                    seed=args.seed,
                    zrange=args.zrange_bgs,
                    rmagrange=args.rmagrange_bgs,
                    sne_rfluxratiorange=args.sne_rfluxratiorange)
            elif thisobj == 'STD':
                fstd = lvmsim.templates.FSTD(wave=wavelengths)
                flux, tmpwave, meta1 = fstd.make_templates(nmodel=nobj,
                                                           seed=args.seed)
            elif thisobj == 'QSO_BAD':  # use STAR template no color cuts
                star = lvmsim.templates.STAR(wave=wavelengths)
                flux, tmpwave, meta1 = star.make_templates(nmodel=nobj,
                                                           seed=args.seed)
            elif thisobj == 'MWS_STAR' or thisobj == 'MWS':
                mwsstar = lvmsim.templates.MWS_STAR(wave=wavelengths)
                flux, tmpwave, meta1 = mwsstar.make_templates(nmodel=nobj,
                                                              seed=args.seed)
            elif thisobj == 'WD':
                wd = lvmsim.templates.WD(wave=wavelengths)
                flux, tmpwave, meta1 = wd.make_templates(nmodel=nobj,
                                                         seed=args.seed)
            elif thisobj == 'SKY':
                flux = np.zeros((nobj, npix))
                meta1 = Table(dict(REDSHIFT=np.zeros(nobj, dtype=np.float32)))
            elif thisobj == 'TEST':
                flux = np.zeros((args.nspec, npix))
                indx = np.where(wave > 5800.0 - 1E-6)[0][0]
                ref_integrated_flux = 1E-10
                ref_cst_flux_density = 1E-17
                single_line = (np.arange(args.nspec) % 2 == 0).astype(
                    np.float32)
                continuum = (np.arange(args.nspec) % 2 == 1).astype(np.float32)

                for spec in range(args.nspec):
                    flux[spec, indx] = single_line[
                        spec] * ref_integrated_flux / np.gradient(wavelengths)[
                            indx]  # single line
                    flux[spec] += continuum[
                        spec] * ref_cst_flux_density  # flat continuum

                meta1 = Table(
                    dict(REDSHIFT=np.zeros(args.nspec, dtype=np.float32),
                         LINE=wave[indx] *
                         np.ones(args.nspec, dtype=np.float32),
                         LINEFLUX=single_line * ref_integrated_flux,
                         CONSTFLUXDENSITY=continuum * ref_cst_flux_density))
            else:
                log.fatal('Unknown object type {}'.format(thisobj))
                sys.exit(1)

            # Pack it in.
            truth['FLUX'][ii] = flux
            meta = vstack([meta, meta1])
            jj.append(ii.tolist())

            # Sanity check on units; templates currently return ergs, not 1e-17 ergs...
            # assert (thisobj == 'SKY') or (np.max(truth['FLUX']) < 1e-6)

        # Sort the metadata table.
        jj = sum(jj, [])
        meta_new = Table()
        for k in range(args.nspec):
            index = int(np.where(np.array(jj) == k)[0])
            meta_new = vstack([meta_new, meta[index]])
        meta = meta_new

        # Add TARGETID and the true OBJTYPE to the metadata table.
        meta.add_column(
            Column(true_objtype, dtype=(str, 10), name='TRUE_OBJTYPE'))
        meta.add_column(Column(targetids, name='TARGETID'))

        # Rename REDSHIFT -> TRUEZ anticipating later table joins with zbest.Z
        meta.rename_column('REDSHIFT', 'TRUEZ')

    # ---------- end simspec

    # explicitly set location on focal plane if needed to support airmass
    # variations when using specsim v0.5
    if qsim.source.focal_xy is None:
        qsim.source.focal_xy = (u.Quantity(0, 'mm'), u.Quantity(100, 'mm'))

    # Set simulation parameters from the simspec header or lvmparams
    bright_objects = ['bgs', 'mws', 'bright', 'BGS', 'MWS', 'BRIGHT_MIX']
    gray_objects = ['gray', 'grey']
    if args.simspec is None:
        object_type = objtype
        flavor = None
    elif simspec.flavor == 'science':
        object_type = None
        flavor = simspec.header['PROGRAM']
    else:
        object_type = None
        flavor = simspec.flavor
        log.warning(
            'Maybe using an outdated simspec file with flavor={}'.format(
                flavor))

    # Set airmass
    if args.airmass is not None:
        qsim.atmosphere.airmass = args.airmass
    elif args.simspec and 'AIRMASS' in simspec.header:
        qsim.atmosphere.airmass = simspec.header['AIRMASS']
    else:
        qsim.atmosphere.airmass = 1.25  # Science Req. Doc L3.3.2

    # Set site location
    if args.location is not None:
        qsim.observation.observatory = args.location
    else:
        qsim.observation.observatory = 'APO'

    # Set exptime
    if args.exptime is not None:
        qsim.observation.exposure_time = args.exptime * u.s
    elif args.simspec and 'EXPTIME' in simspec.header:
        qsim.observation.exposure_time = simspec.header['EXPTIME'] * u.s
    elif objtype in bright_objects:
        qsim.observation.exposure_time = lvmparams['exptime_bright'] * u.s
    else:
        qsim.observation.exposure_time = lvmparams['exptime_dark'] * u.s

    # Set Moon Phase
    if args.moon_phase is not None:
        qsim.atmosphere.moon.moon_phase = args.moon_phase
    elif args.simspec and 'MOONFRAC' in simspec.header:
        qsim.atmosphere.moon.moon_phase = simspec.header['MOONFRAC']
    elif flavor in bright_objects or object_type in bright_objects:
        qsim.atmosphere.moon.moon_phase = 0.7
    elif flavor in gray_objects:
        qsim.atmosphere.moon.moon_phase = 0.1
    else:
        qsim.atmosphere.moon.moon_phase = 0.5

    # Set Moon Zenith
    if args.moon_zenith is not None:
        qsim.atmosphere.moon.moon_zenith = args.moon_zenith * u.deg
    elif args.simspec and 'MOONALT' in simspec.header:
        qsim.atmosphere.moon.moon_zenith = simspec.header['MOONALT'] * u.deg
    elif flavor in bright_objects or object_type in bright_objects:
        qsim.atmosphere.moon.moon_zenith = 30 * u.deg
    elif flavor in gray_objects:
        qsim.atmosphere.moon.moon_zenith = 80 * u.deg
    else:
        qsim.atmosphere.moon.moon_zenith = 100 * u.deg

    # Set Moon - Object Angle
    if args.moon_angle is not None:
        qsim.atmosphere.moon.separation_angle = args.moon_angle * u.deg
    elif args.simspec and 'MOONSEP' in simspec.header:
        qsim.atmosphere.moon.separation_angle = simspec.header[
            'MOONSEP'] * u.deg
    elif flavor in bright_objects or object_type in bright_objects:
        qsim.atmosphere.moon.separation_angle = 50 * u.deg
    elif flavor in gray_objects:
        qsim.atmosphere.moon.separation_angle = 60 * u.deg
    else:
        qsim.atmosphere.moon.separation_angle = 60 * u.deg

    # Initialize per-camera output arrays that will be saved
    waves, trueflux, noisyflux, obsivar, resolution, sflux = {}, {}, {}, {}, {}, {}

    maxbin = 0
    nmax = args.nspec
    for camera in qsim.instrument.cameras:
        # Lookup this camera's resolution matrix and convert to the sparse format used in lvmspec.
        R = Resolution(camera.get_output_resolution_matrix())
        resolution[camera.name] = np.tile(R.to_fits_array(),
                                          [args.nspec, 1, 1])
        waves[camera.name] = (camera.output_wavelength.to(
            u.Angstrom).value.astype(np.float32))
        nwave = len(waves[camera.name])
        maxbin = max(maxbin, len(waves[camera.name]))
        nobj = np.zeros((nmax, 3, maxbin))  # object photons
        nsky = np.zeros((nmax, 3, maxbin))  # sky photons
        nivar = np.zeros((nmax, 3, maxbin))  # inverse variance (object+sky)
        cframe_observedflux = np.zeros(
            (nmax, 3, maxbin))  # calibrated object flux
        cframe_ivar = np.zeros(
            (nmax, 3, maxbin))  # inverse variance of calibrated object flux
        cframe_rand_noise = np.zeros(
            (nmax, 3, maxbin))  # random Gaussian noise to calibrated flux
        sky_ivar = np.zeros((nmax, 3, maxbin))  # inverse variance of sky
        sky_rand_noise = np.zeros(
            (nmax, 3, maxbin))  # random Gaussian noise to sky only
        frame_rand_noise = np.zeros(
            (nmax, 3, maxbin))  # random Gaussian noise to nobj+nsky
        trueflux[camera.name] = np.empty(
            (args.nspec, nwave))  # calibrated flux
        noisyflux[camera.name] = np.empty(
            (args.nspec, nwave))  # observed flux with noise
        obsivar[camera.name] = np.empty(
            (args.nspec, nwave))  # inverse variance of flux
        if args.simspec:
            dw = np.gradient(simspec.wave[camera.name])
        else:
            sflux = np.empty((args.nspec, npix))

    # - Check if input simspec is for a continuum flat lamp instead of science
    # - This does not convolve to per-fiber resolution
    if args.simspec:
        if simspec.flavor == 'flat':
            log.info("Simulating flat lamp exposure")
            for i, camera in enumerate(qsim.instrument.cameras):
                channel = camera.name
                assert camera.output_wavelength.unit == u.Angstrom
                num_pixels = len(waves[channel])
                dw = np.gradient(simspec.wave[channel])
                meanspec = resample_flux(
                    waves[channel], simspec.wave[channel],
                    np.average(simspec.phot[channel] / dw, axis=0))
                fiberflat = random_state.normal(loc=1.0,
                                                scale=1.0 / np.sqrt(meanspec),
                                                size=(nspec, num_pixels))
                ivar = np.tile(meanspec, [nspec, 1])
                mask = np.zeros((simspec.nspec, num_pixels), dtype=np.uint32)

                for kk in range((args.nspec + args.nstart - 1) //
                                args.n_fibers + 1):
                    camera = channel + str(kk)
                    outfile = lvmspec.io.findfile('fiberflat', night, expid,
                                                  camera)
                    start = max(args.n_fibers * kk, args.nstart)
                    end = min(args.n_fibers * (kk + 1), nmax)

                    if (args.spectrograph <= kk):
                        log.info(
                            "Writing files for channel:{}, spectrograph:{}, spectra:{} to {}"
                            .format(channel, kk, start, end))

                    ff = FiberFlat(waves[channel],
                                   fiberflat[start:end, :],
                                   ivar[start:end, :],
                                   mask[start:end, :],
                                   meanspec,
                                   header=dict(CAMERA=camera))
                    write_fiberflat(outfile, ff)
                    filePath = lvmspec.io.findfile("fiberflat", night, expid,
                                                   camera)
                    log.info("Wrote file {}".format(filePath))

            sys.exit(0)

    # Repeat the simulation for all spectra
    scale = 1e-17
    fluxunits = scale * u.erg / (u.s * u.cm**2 * u.Angstrom)
    for j in range(args.nspec):

        thisobjtype = objtype[j]
        sys.stdout.flush()
        if flavor == 'arc':
            qsim.source.update_in('Quickgen source {0}'.format, 'perfect',
                                  wavelengths * u.Angstrom,
                                  spectra * fluxunits)
        else:
            qsim.source.update_in('Quickgen source {0}'.format(j),
                                  thisobjtype.lower(),
                                  wavelengths * u.Angstrom,
                                  spectra[j, :] * fluxunits)
        qsim.source.update_out()

        qsim.simulate()
        qsim.generate_random_noise(random_state)

        for i, output in enumerate(qsim.camera_output):
            assert output['observed_flux'].unit == 1e17 * fluxunits
            # Extract the simulation results needed to create our uncalibrated
            # frame output file.
            num_pixels = len(output)
            nobj[j, i, :num_pixels] = output['num_source_electrons'][:, 0]
            nsky[j, i, :num_pixels] = output['num_sky_electrons'][:, 0]
            nivar[j, i, :num_pixels] = 1.0 / output['variance_electrons'][:, 0]

            # Get results for our flux-calibrated output file.
            cframe_observedflux[
                j, i, :num_pixels] = 1e17 * output['observed_flux'][:, 0]
            cframe_ivar[
                j,
                i, :num_pixels] = 1e-34 * output['flux_inverse_variance'][:, 0]

            # Fill brick arrays from the results.
            camera = output.meta['name']
            trueflux[camera][j][:] = 1e17 * output['observed_flux'][:, 0]
            noisyflux[camera][j][:] = 1e17 * (
                output['observed_flux'][:, 0] +
                output['flux_calibration'][:, 0] *
                output['random_noise_electrons'][:, 0])
            obsivar[camera][j][:] = 1e-34 * output['flux_inverse_variance'][:,
                                                                            0]

            # Use the same noise realization in the cframe and frame, without any
            # additional noise from sky subtraction for now.
            frame_rand_noise[
                j, i, :num_pixels] = output['random_noise_electrons'][:, 0]
            cframe_rand_noise[j, i, :num_pixels] = 1e17 * (
                output['flux_calibration'][:, 0] *
                output['random_noise_electrons'][:, 0])

            # The sky output file represents a model fit to ~40 sky fibers.
            # We reduce the variance by a factor of 25 to account for this and
            # give the sky an independent (Gaussian) noise realization.
            sky_ivar[
                j,
                i, :num_pixels] = 25.0 / (output['variance_electrons'][:, 0] -
                                          output['num_source_electrons'][:, 0])
            sky_rand_noise[j, i, :num_pixels] = random_state.normal(
                scale=1.0 / np.sqrt(sky_ivar[j, i, :num_pixels]),
                size=num_pixels)

    armName = {"b": 0, "r": 1, "z": 2}
    for channel in 'brz':

        # Before writing, convert from counts/bin to counts/A (as in Pixsim output)
        # Quicksim Default:
        # FLUX - input spectrum resampled to this binning; no noise added [1e-17 erg/s/cm2/s/Ang]
        # COUNTS_OBJ - object counts in 0.5 Ang bin
        # COUNTS_SKY - sky counts in 0.5 Ang bin

        num_pixels = len(waves[channel])
        dwave = np.gradient(waves[channel])
        nobj[:, armName[channel], :num_pixels] /= dwave
        frame_rand_noise[:, armName[channel], :num_pixels] /= dwave
        nivar[:, armName[channel], :num_pixels] *= dwave**2
        nsky[:, armName[channel], :num_pixels] /= dwave
        sky_rand_noise[:, armName[channel], :num_pixels] /= dwave
        sky_ivar[:, armName[channel], :num_pixels] /= dwave**2

        # Now write the outputs in DESI standard file system. None of the output file can have more than args.n_fibers spectra

        # Looping over spectrograph
        for ii in range((args.nspec + args.nstart - 1) // args.n_fibers + 1):

            start = max(args.n_fibers * ii,
                        args.nstart)  # first spectrum for a given spectrograph
            end = min(args.n_fibers * (ii + 1),
                      nmax)  # last spectrum for the spectrograph

            if (args.spectrograph <= ii):
                camera = "{}{}".format(channel, ii)
                log.info(
                    "Writing files for channel:{}, spectrograph:{}, spectra:{} to {}"
                    .format(channel, ii, start, end))
                num_pixels = len(waves[channel])

                # Write frame file
                framefileName = lvmspec.io.findfile("frame", night, expid,
                                                    camera)

                frame_flux = nobj[start:end, armName[channel], :num_pixels] + \
                    nsky[start:end, armName[channel], :num_pixels] + \
                    frame_rand_noise[start:end, armName[channel], :num_pixels]
                frame_ivar = nivar[start:end, armName[channel], :num_pixels]

                # required for slicing the resolution metric, resolusion matrix has (nspec, ndiag, wave)
                # for example if nstart =400, nspec=150: two spectrographs:
                # 400-499=> 0 spectrograph, 500-549 => 1
                sh1 = frame_flux.shape[0]

                if (args.nstart == start):
                    resol = resolution[channel][:sh1, :, :]
                else:
                    resol = resolution[channel][-sh1:, :, :]

                # must create lvmspec.Frame object
                frame = Frame(waves[channel],
                              frame_flux,
                              frame_ivar,
                              resolution_data=resol,
                              spectrograph=ii,
                              fibermap=fibermap[start:end],
                              meta=dict(CAMERA=camera, FLAVOR=simspec.flavor))
                lvmspec.io.write_frame(framefileName, frame)

                framefilePath = lvmspec.io.findfile("frame", night, expid,
                                                    camera)
                log.info("Wrote file {}".format(framefilePath))

                if args.frameonly or simspec.flavor == 'arc':
                    continue

                # Write cframe file
                cframeFileName = lvmspec.io.findfile("cframe", night, expid,
                                                     camera)
                cframeFlux = cframe_observedflux[start:end, armName[channel], :num_pixels] + \
                    cframe_rand_noise[start:end, armName[channel], :num_pixels]
                cframeIvar = cframe_ivar[start:end,
                                         armName[channel], :num_pixels]

                # must create lvmspec.Frame object
                cframe = Frame(waves[channel],
                               cframeFlux,
                               cframeIvar,
                               resolution_data=resol,
                               spectrograph=ii,
                               fibermap=fibermap[start:end],
                               meta=dict(CAMERA=camera, FLAVOR=simspec.flavor))
                lvmspec.io.frame.write_frame(cframeFileName, cframe)

                cframefilePath = lvmspec.io.findfile("cframe", night, expid,
                                                     camera)
                log.info("Wrote file {}".format(cframefilePath))

                # Write sky file
                skyfileName = lvmspec.io.findfile("sky", night, expid, camera)
                skyflux = nsky[start:end, armName[channel], :num_pixels] + \
                    sky_rand_noise[start:end, armName[channel], :num_pixels]
                skyivar = sky_ivar[start:end, armName[channel], :num_pixels]
                skymask = np.zeros(skyflux.shape, dtype=np.uint32)

                # must create lvmspec.Sky object
                skymodel = SkyModel(waves[channel],
                                    skyflux,
                                    skyivar,
                                    skymask,
                                    header=dict(CAMERA=camera))
                lvmspec.io.sky.write_sky(skyfileName, skymodel)

                skyfilePath = lvmspec.io.findfile("sky", night, expid, camera)
                log.info("Wrote file {}".format(skyfilePath))

                # Write calib file
                calibVectorFile = lvmspec.io.findfile("calib", night, expid,
                                                      camera)
                flux = cframe_observedflux[start:end,
                                           armName[channel], :num_pixels]
                phot = nobj[start:end, armName[channel], :num_pixels]
                calibration = np.zeros_like(phot)
                jj = (flux > 0)
                calibration[jj] = phot[jj] / flux[jj]

                # - TODO: what should calibivar be?
                # - For now, model it as the noise of combining ~10 spectra
                calibivar = 10 / cframe_ivar[start:end,
                                             armName[channel], :num_pixels]
                # mask=(1/calibivar>0).astype(int)??
                mask = np.zeros(calibration.shape, dtype=np.uint32)

                # write flux calibration
                fluxcalib = FluxCalib(waves[channel], calibration, calibivar,
                                      mask)
                write_flux_calibration(calibVectorFile, fluxcalib)

                calibfilePath = lvmspec.io.findfile("calib", night, expid,
                                                    camera)
                log.info("Wrote file {}".format(calibfilePath))
コード例 #9
0
class TestFiberFlatObject(unittest.TestCase):
    def setUp(self):
        self.nspec = 5
        self.nwave = 10
        self.wave = np.arange(self.nwave)
        self.fiberflat = np.random.uniform(size=(self.nspec, self.nwave))
        self.ivar = np.ones(self.fiberflat.shape)
        self.mask = np.zeros(self.fiberflat.shape, dtype=np.uint32)
        self.meanspec = np.random.uniform(size=self.nwave)
        self.ff = FiberFlat(self.wave, self.fiberflat, self.ivar, self.mask,
                            self.meanspec)

    def test_init(self):
        for key in ('wave', 'fiberflat', 'ivar', 'mask', 'meanspec'):
            x = self.ff.__getattribute__(key)
            y = self.__getattribute__(key)
            self.assertTrue(np.all(x == y), key)

        self.assertEqual(self.nspec, self.ff.nspec)
        self.assertEqual(self.nwave, self.ff.nwave)

    def test_dimensions(self):
        #- check dimensionality mismatches
        with self.assertRaises(ValueError):
            FiberFlat(self.wave, self.wave, self.ivar, self.mask,
                      self.meanspec)

        with self.assertRaises(ValueError):
            FiberFlat(self.wave, self.wave, self.ivar, self.mask,
                      self.meanspec)

        with self.assertRaises(ValueError):
            FiberFlat(self.wave, self.fiberflat, self.ivar, self.mask,
                      self.fiberflat)

        with self.assertRaises(ValueError):
            FiberFlat(self.wave, self.fiberflat[0:2], self.ivar, self.mask,
                      self.meanspec)

        with self.assertRaises(ValueError):
            FiberFlat(self.fiberflat, self.fiberflat, self.ivar, self.mask,
                      self.meanspec)

        with self.assertRaises(ValueError):
            FiberFlat(self.wave, self.fiberflat, self.wave, self.mask,
                      self.meanspec)

        with self.assertRaises(ValueError):
            FiberFlat(self.wave, self.fiberflat, self.ivar, self.mask[0:2, :],
                      self.meanspec)

        fibers = np.arange(self.nspec)
        FiberFlat(self.wave,
                  self.fiberflat,
                  self.ivar,
                  self.mask,
                  self.meanspec,
                  fibers=fibers)
        with self.assertRaises(ValueError):
            FiberFlat(self.wave,
                      self.fiberflat,
                      self.ivar,
                      self.mask,
                      self.meanspec,
                      fibers=fibers[1:])

    def test_slice(self):
        x = self.ff[1]
        x = self.ff[1:2]
        x = self.ff[[1, 2, 3]]
        x = self.ff[self.ff.fibers < 3]