Beispiel #1
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    def test_simobs(self):
        """
        Simulate observations using cached versions of the sed grid and noise model
        and compare the result to a cached version.
        """
        # download files specific to this test
        simobs_fname_cache = download_rename("beast_example_phat_simobs.fits")

        # get the physics model grid - includes priors
        modelsedgrid = SEDGrid(self.seds_fname_cache)

        # read in the noise model - includes bias, unc, and completeness
        noisegrid = noisemodel.get_noisemodelcat(self.noise_fname_cache)

        table_new = gen_SimObs_from_sedgrid(
            modelsedgrid,
            noisegrid,
            nsim=100,
            compl_filter="max",
            ranseed=1234,
        )

        # check that the simobs files are exactly the same
        table_cache = Table.read(simobs_fname_cache)

        # to avoid issues with uppercase vs lowercase column names, make them all
        # the same before comparing
        for col in table_new.colnames:
            table_new[col].name = col.upper()
        for col in table_cache.colnames:
            table_cache[col].name = col.upper()

        compare_tables(table_cache, table_new)
Beispiel #2
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def test_trim_grid():

    # download the needed files
    vega_fname = download_rename('vega.hd5')
    seds_fname = download_rename('beast_example_phat_seds.grid.hd5')
    noise_fname = download_rename('beast_example_phat_noisemodel.hd5')

    # download cached version of noisemodel on the sed grid
    simobs_fname_cache = download_rename('beast_example_phat_simobs.fits')

    ################

    # get the physics model grid - includes priors
    modelsedgrid = FileSEDGrid(seds_fname)

    # read in the noise model - includes bias, unc, and completeness
    noisegrid = noisemodel.get_noisemodelcat(noise_fname)

    table_new = gen_SimObs_from_sedgrid(modelsedgrid,
                                        noisegrid,
                                        nsim=100,
                                        compl_filter="f475w",
                                        ranseed=1234,
                                        vega_fname=vega_fname)

    # check that the simobs files are exactly the same
    table_cache = Table.read(simobs_fname_cache)

    compare_tables(table_cache, table_new)
Beispiel #3
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def test_simobs():

    # download the needed files
    vega_fname = download_rename("vega.hd5")
    seds_fname = download_rename("beast_example_phat_seds.grid.hd5")
    noise_fname = download_rename("beast_example_phat_noisemodel.grid.hd5")

    # download cached version of noisemodel on the sed grid
    simobs_fname_cache = download_rename("beast_example_phat_simobs.fits")

    ################

    # get the physics model grid - includes priors
    modelsedgrid = SEDGrid(seds_fname)

    # read in the noise model - includes bias, unc, and completeness
    noisegrid = noisemodel.get_noisemodelcat(noise_fname)

    table_new = gen_SimObs_from_sedgrid(
        modelsedgrid,
        noisegrid,
        nsim=100,
        compl_filter="f475w",
        ranseed=1234,
        vega_fname=vega_fname,
    )

    # check that the simobs files are exactly the same
    table_cache = Table.read(simobs_fname_cache)

    # to avoid issues with uppercase vs lowercase column names, make them all
    # the same before comparing
    for col in table_new.colnames:
        table_new[col].name = col.upper()
    for col in table_cache.colnames:
        table_cache[col].name = col.upper()

    compare_tables(table_cache, table_new)
Beispiel #4
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def simulate_obs(
    physgrid_list,
    noise_model_list,
    output_catalog,
    nsim=100,
    compl_filter="F475W",
    weight_to_use='weight',
    ranseed=None,
):
    """
    Wrapper for creating a simulated photometry.

    Parameters
    ----------
    physgrid_list : list of strings
        Name of the physics model file.  If there are multiple physics model
        grids (i.e., if there are subgrids), list them all here, and they will
        each be sampled nsim/len(physgrid_list) times.

    noise_model_list : list of strings
        Name of the noise model file.  If there are multiple files for
        physgrid_list (because of subgrids), list the noise model file
        associated with each physics model file.

    output_catalog : string
        Name of the output simulated photometry catalog

    n_sim : int (default=100)
        Number of simulated objects to create.  If nsim/len(physgrid_list) isn't
        an integer, this will be increased so that each grid has the same
        number of samples.

    compl_filter : string (default='F475W')
        filter name to use for completeness

    weight_to_use : string (default='weight')
        Set to either 'weight' (prior+grid), 'prior_weight', or 'grid_weight' to
        choose the weighting for SED selection.

    ranseed : int
        seed for random number generator

    """

    # numbers of samples to do
    # (ensure there are enough for even sampling of multiple model grids)
    n_phys = len(physgrid_list)
    samples_per_grid = int(np.ceil(nsim / n_phys))

    # list to hold all simulation tables
    simtable_list = []

    # make a table for each physics model + noise model
    for physgrid, noise_model in zip(np.atleast_1d(physgrid_list),
                                     np.atleast_1d(noise_model_list)):

        # get the physics model grid - includes priors
        modelsedgrid = SEDGrid(str(physgrid))

        # read in the noise model - includes bias, unc, and completeness
        noisegrid = noisemodel.get_noisemodelcat(str(noise_model))

        # generate the table
        simtable = gen_SimObs_from_sedgrid(
            modelsedgrid,
            noisegrid,
            nsim=samples_per_grid,
            compl_filter=compl_filter,
            weight_to_use=weight_to_use,
            ranseed=ranseed,
        )

        # append to the list
        simtable_list.append(simtable)

    # stack all the tables into one and write it out
    vstack(simtable_list).write(output_catalog, overwrite=True)
Beispiel #5
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    parser.add_argument("obsgrid", help="filename of observation/nosie grid")
    parser.add_argument("outfile", help="filename for simulated observations")
    parser.add_argument("--nsim",
                        default=100,
                        type=int,
                        help="number of simulated objects")
    parser.add_argument("--compl_filter",
                        default="F475W",
                        help="filter name to use for completeness")
    parser.add_argument("--ranseed",
                        default=None,
                        type=int,
                        help="seed for random number generator")
    args = parser.parse_args()

    # get the physics model grid - includes priors
    modelsedgrid = FileSEDGrid(args.physgrid)

    # read in the noise model - includes bias, unc, and completeness
    noisegrid = noisemodel.get_noisemodelcat(args.obsgrid)

    simtable = gen_SimObs_from_sedgrid(
        modelsedgrid,
        noisegrid,
        nsim=args.nsim,
        compl_filter=args.compl_filter,
        ranseed=args.ranseed,
    )

    simtable.write(args.outfile, overwrite=True)
Beispiel #6
0
def simulate_obs(
    physgrid_list,
    noise_model_list,
    output_catalog,
    beastinfo_list=None,
    nsim=100,
    compl_filter="F475W",
    complcut=None,
    magcut=None,
    weight_to_use="weight",
    ranseed=None,
):
    """
    Simulate photometry based on a physicsmodel grid(s) and observation model(s).

    Parameters
    ----------
    physgrid_list : list of strings
        Name of the physics model file.  If there are multiple physics model
        grids (i.e., if there are subgrids), list them all here, and they will
        each be sampled nsim/len(physgrid_list) times.

    noise_model_list : list of strings
        Name of the noise model file.  If there are multiple files for
        physgrid_list (because of subgrids), list the noise model files
        associated with each physics model file.

    output_catalog : string
        Name of the output simulated photometry catalog

    beastinfo_list : list of strings (default=None)
        Name of the beast info file.  The mass and age prior models are read
        from this model to use to compute the number of stars to simulate. If
        there are multiple files for physgrid_list (because of subgrids), list
        the beast info files associated with each physics model file.

    n_sim : int (default=100)
        Number of simulated objects to create if beastinfo_list is not given. If
        nsim/len(physgrid_list) isn't an integer, this will be increased so that
        each grid has the same number of samples.

    compl_filter : str (default=F475W)
        filter to use for completeness (required for toothpick model)
        set to max to use the max value in all filters

    complcut : float (defualt=None)
        completeness cut for only including model seds above the given
        completeness, where the cut ranges from 0 to 1.

    magcut : float (defualt=None)
        faint-end magnitude cut for only including model seds brighter
        than the given magnitude in compl_filter.

    weight_to_use : string (default='weight')
        Set to either 'weight' (prior+grid), 'prior_weight', 'grid_weight',
        or 'uniform' (this option is valid only when nsim is supplied) to
        choose the weighting for SED selection.

    ranseed : int
        seed for random number generator
    """
    # numbers of samples to do
    # (ensure there are enough for even sampling of multiple model grids)
    n_phys = len(np.atleast_1d(physgrid_list))
    nsim = int(nsim)
    samples_per_grid = int(np.ceil(nsim / n_phys))

    if complcut is not None:
        complcut = float(complcut)

    if magcut is not None:
        magcut = float(magcut)

    if ranseed is not None:
        ranseed = int(ranseed)

    # list to hold all simulation tables
    simtable_list = []

    # make a table for each physics model + noise model
    for k, physgrid in enumerate(np.atleast_1d(physgrid_list)):
        noise_model = np.atleast_1d(noise_model_list)[k]

        # get the physics model grid - includes priors
        modelsedgrid = SEDGrid(str(physgrid))

        # read in the noise model - includes bias, unc, and completeness
        noisegrid = noisemodel.get_noisemodelcat(str(noise_model))

        if beastinfo_list is not None:
            with asdf.open(np.atleast_1d(beastinfo_list)[k]) as af:
                binfo = af.tree
                age_prior_model = binfo["age_prior_model"]
                mass_prior_model = binfo["mass_prior_model"]
        else:
            age_prior_model = None
            mass_prior_model = None

        # generate the table
        simtable = gen_SimObs_from_sedgrid(
            modelsedgrid,
            noisegrid,
            age_prior_model=age_prior_model,
            mass_prior_model=mass_prior_model,
            nsim=samples_per_grid,
            compl_filter=compl_filter,
            complcut=complcut,
            magcut=magcut,
            weight_to_use=weight_to_use,
            ranseed=ranseed,
        )

        # append to the list
        simtable_list.append(simtable)

    # stack all the tables into one and write it out
    vstack(simtable_list).write(output_catalog, overwrite=True)