Пример #1
0
def post(info, sample=None):
    logger_setup(info.get(_debug), info.get(_debug_file))
    log = logging.getLogger(__name__.split(".")[-1])
    # MARKED FOR DEPRECATION IN v3.0
    # BEHAVIOUR TO BE REPLACED BY ERROR:
    check_deprecated_modules_path(info)
    # END OF DEPRECATION BLOCK
    try:
        info_post = info[_post]
    except KeyError:
        raise LoggedError(log, "No 'post' block given. Nothing to do!")
    if get_mpi_rank():
        log.warning(
            "Post-processing is not yet MPI-aware. Doing nothing for rank > 1 processes.")
        return
    if info.get(_resume):
        log.warning("Resuming not implemented for post-processing. Re-starting.")
    # 1. Load existing sample
    output_in = get_output(output_prefix=info.get(_output_prefix))
    if output_in:
        try:
            info_in = output_in.reload_updated_info()
        except FileNotFoundError:
            raise LoggedError(log, "Error loading input model: "
                                   "could not find input info at %s",
                              output_in.file_updated)
    else:
        info_in = deepcopy_where_possible(info)
    dummy_model_in = DummyModel(info_in[_params], info_in[kinds.likelihood],
                                info_in.get(_prior, None))
    if output_in:
        if not output_in.find_collections():
            raise LoggedError(log, "No samples found for the input model with prefix %s",
                              os.path.join(output_in.folder, output_in.prefix))
        collection_in = output_in.load_collections(
            dummy_model_in, skip=info_post.get("skip", 0), thin=info_post.get("thin", 1),
            concatenate=True)
    elif sample:
        if isinstance(sample, Collection):
            sample = [sample]
        collection_in = deepcopy(sample[0])
        for s in sample[1:]:
            try:
                collection_in.append(s)
            except:
                raise LoggedError(log, "Failed to load some of the input samples.")
    else:
        raise LoggedError(log,
                          "Not output from where to load from or input collections given.")
    log.info("Will process %d samples.", len(collection_in))
    if len(collection_in) <= 1:
        raise LoggedError(
            log, "Not enough samples for post-processing. Try using a larger sample, "
                 "or skipping or thinning less.")
    # 2. Compare old and new info: determine what to do
    add = info_post.get(_post_add, {}) or {}
    remove = info_post.get(_post_remove, {})
    # Add a dummy 'one' likelihood, to absorb unused parameters
    if not add.get(kinds.likelihood):
        add[kinds.likelihood] = {}
    add[kinds.likelihood]["one"] = None
    # Expand the "add" info
    add = update_info(add)
    # 2.1 Adding/removing derived parameters and changes in priors of sampled parameters
    out = {_params: deepcopy_where_possible(info_in[_params])}
    for p in remove.get(_params, {}):
        pinfo = info_in[_params].get(p)
        if pinfo is None or not is_derived_param(pinfo):
            raise LoggedError(
                log,
                "You tried to remove parameter '%s', which is not a derived parameter. "
                "Only derived parameters can be removed during post-processing.", p)
        out[_params].pop(p)
    # Force recomputation of aggregated chi2
    for p in list(out[_params]):
        if p.startswith(_get_chi2_name("")):
            out[_params].pop(p)
    mlprior_names_add = []
    for p, pinfo in add.get(_params, {}).items():
        pinfo_in = info_in[_params].get(p)
        if is_sampled_param(pinfo):
            if not is_sampled_param(pinfo_in):
                # No added sampled parameters (de-marginalisation not implemented)
                if pinfo_in is None:
                    raise LoggedError(
                        log, "You added a new sampled parameter %r (maybe accidentally "
                             "by adding a new likelihood that depends on it). "
                             "Adding new sampled parameters is not possible. Try fixing "
                             "it to some value.", p)
                else:
                    raise LoggedError(
                        log,
                        "You tried to change the prior of parameter '%s', "
                        "but it was not a sampled parameter. "
                        "To change that prior, you need to define as an external one.", p)
            if mlprior_names_add[:1] != _prior_1d_name:
                mlprior_names_add = ([_minuslogprior + _separator + _prior_1d_name]
                                     + mlprior_names_add)
        elif is_derived_param(pinfo):
            if p in out[_params]:
                raise LoggedError(
                    log, "You tried to add derived parameter '%s', which is already "
                         "present. To force its recomputation, 'remove' it too.", p)
        elif is_fixed_param(pinfo):
            # Only one possibility left "fixed" parameter that was not present before:
            # input of new likelihood, or just an argument for dynamical derived (dropped)
            if ((p in info_in[_params] and
                 pinfo[partag.value] != (pinfo_in or {}).get(partag.value, None))):
                raise LoggedError(
                    log,
                    "You tried to add a fixed parameter '%s: %r' that was already present"
                    " but had a different value or was not fixed. This is not allowed. "
                    "The old info of the parameter was '%s: %r'",
                    p, dict(pinfo), p, dict(pinfo_in))
        else:
            raise LoggedError(log, "This should not happen. Contact the developers.")
        out[_params][p] = pinfo
    # For the likelihood only, turn the rest of *derived* parameters into constants,
    # so that the likelihoods do not try to compute them)
    # But be careful to exclude *input* params that have a "derived: True" value
    # (which in "updated info" turns into "derived: 'lambda [x]: [x]'")
    out_params_like = deepcopy_where_possible(out[_params])
    for p, pinfo in out_params_like.items():
        if ((is_derived_param(pinfo) and not (partag.value in pinfo)
             and p not in add.get(_params, {}))):
            out_params_like[p] = {partag.value: np.nan, partag.drop: True}
    # 2.2 Manage adding/removing priors and likelihoods
    warn_remove = False
    for level in [_prior, kinds.likelihood]:
        out[level] = getattr(dummy_model_in, level)
        if level == _prior:
            out[level].remove(_prior_1d_name)
        for pdf in info_post.get(_post_remove, {}).get(level, []) or []:
            try:
                out[level].remove(pdf)
                warn_remove = True
            except ValueError:
                raise LoggedError(
                    log, "Trying to remove %s '%s', but it is not present. "
                         "Existing ones: %r", level, pdf, out[level])
    if warn_remove:
        log.warning("You are removing a prior or likelihood pdf. "
                    "Notice that if the resulting posterior is much wider "
                    "than the original one, or displaced enough, "
                    "it is probably safer to explore it directly.")
    if _prior in add:
        mlprior_names_add += [_minuslogprior + _separator + name for name in add[_prior]]
        out[_prior] += list(add[_prior])
    prior_recompute_1d = (
            mlprior_names_add[:1] == [_minuslogprior + _separator + _prior_1d_name])
    # Don't initialise the theory code if not adding/recomputing theory,
    # theory-derived params or likelihoods
    recompute_theory = info_in.get(kinds.theory) and not (
            list(add[kinds.likelihood]) == ["one"] and
            not any(is_derived_param(pinfo) for pinfo in add.get(_params, {}).values()))
    if recompute_theory:
        # Inherit from the original chain (needs input|output_params, renames, etc
        add_theory = add.get(kinds.theory)
        if add_theory:
            info_theory_out = {}
            if len(add_theory) > 1:
                log.warning('Importance sampling with more than one theory is '
                            'not really tested')
            add_theory = add_theory.copy()
            for theory, theory_info in info_in[kinds.theory].items():
                theory_copy = deepcopy_where_possible(theory_info)
                if theory in add_theory:
                    info_theory_out[theory] = \
                        recursive_update(theory_copy, add_theory.pop(theory))
                else:
                    info_theory_out[theory] = theory_copy
            info_theory_out.update(add_theory)
        else:
            info_theory_out = deepcopy_where_possible(info_in[kinds.theory])
    else:
        info_theory_out = None
    chi2_names_add = [
        _get_chi2_name(name) for name in add[kinds.likelihood] if name != "one"]
    out[kinds.likelihood] += [l for l in add[kinds.likelihood] if l != "one"]
    if recompute_theory:
        log.warning("You are recomputing the theory, but in the current version this does"
                    " not force recomputation of any likelihood or derived parameter, "
                    "unless explicitly removed+added.")
    for level in [_prior, kinds.likelihood]:
        for i, x_i in enumerate(out[level]):
            if x_i in list(out[level])[i + 1:]:
                raise LoggedError(
                    log, "You have added %s '%s', which was already present. If you "
                         "want to force its recomputation, you must also 'remove' it.",
                    level, x_i)
    # 3. Create output collection
    if _post_suffix not in info_post:
        raise LoggedError(log, "You need to provide a '%s' for your chains.",
                          _post_suffix)
    # Use default prefix if it exists. If it does not, produce no output by default.
    # {post: {output: None}} suppresses output, and if it's a string, updates it.
    out_prefix = info_post.get(_output_prefix, info.get(_output_prefix))
    if out_prefix not in [None, False]:
        out_prefix += _separator_files + _post + _separator_files + info_post[
            _post_suffix]
    output_out = get_output(output_prefix=out_prefix, force=info.get(_force))
    if output_out and not output_out.force and output_out.find_collections():
        raise LoggedError(log, "Found existing post-processing output with prefix %r. "
                               "Delete it manually or re-run with `force: True` "
                               "(or `-f`, `--force` from the shell).", out_prefix)
    elif output_out and output_out.force:
        output_out.delete_infos()
        for regexp in output_out.find_collections():
            output_out.delete_with_regexp(re.compile(regexp))
    info_out = deepcopy_where_possible(info)
    info_out[_post] = info_post
    # Updated with input info and extended (updated) add info
    info_out.update(info_in)
    info_out[_post][_post_add] = add
    dummy_model_out = DummyModel(out[_params], out[kinds.likelihood],
                                 info_prior=out[_prior])
    if recompute_theory:
        # TODO: May need updating for more than one, or maybe can be removed
        theory = list(info_theory_out)[0]
        if _input_params not in info_theory_out[theory]:
            raise LoggedError(
                log,
                "You appear to be post-processing a chain generated with an older "
                "version of Cobaya. For post-processing to work, please edit the "
                "'[root].updated.yaml' file of the original chain to add, inside the "
                "theory code block, the list of its input parameters. E.g.\n----\n"
                "theory:\n  %s:\n    input_params: [param1, param2, ...]\n"
                "----\nIf you get strange errors later, it is likely that you did not "
                "specify the correct set of theory parameters.\n"
                "The full set of input parameters are %s.",
                theory, list(dummy_model_out.parameterization.input_params()))
    # TODO: check allow_renames=False?
    # TODO: May well be simplifications here, this is v close to pre-refactor logic
    # Have not gone through or understood all the parameterization  stuff
    model_add = Model(out_params_like, add[kinds.likelihood], info_prior=add.get(_prior),
                      info_theory=info_theory_out, packages_path=info.get(_packages_path),
                      allow_renames=False, post=True,
                      prior_parameterization=dummy_model_out.parameterization)
    # Remove auxiliary "one" before dumping -- 'add' *is* info_out[_post][_post_add]
    add[kinds.likelihood].pop("one")
    collection_out = Collection(dummy_model_out, output_out, name="1")
    output_out.check_and_dump_info(None, info_out, check_compatible=False)
    # Prepare recomputation of aggregated chi2
    # (they need to be recomputed by hand, because its autocomputation won't pick up
    #  old likelihoods for a given type)
    all_types = {
        like: str_to_list(add[kinds.likelihood].get(
            like, info_in[kinds.likelihood].get(like)).get("type", []) or [])
        for like in out[kinds.likelihood]}
    types = set(chain(*list(all_types.values())))
    inv_types = {t: [like for like, like_types in all_types.items() if t in like_types]
                 for t in types}
    # 4. Main loop!
    log.info("Running post-processing...")
    last_percent = 0
    for i, point in collection_in.data.iterrows():
        log.debug("Point: %r", point)
        sampled = [point[param] for param in
                   dummy_model_in.parameterization.sampled_params()]
        derived = {param: point.get(param, None)
                   for param in dummy_model_out.parameterization.derived_params()}
        inputs = {param: point.get(
            param, dummy_model_in.parameterization.constant_params().get(
                param, dummy_model_out.parameterization.constant_params().get(
                    param, None)))
            for param in dummy_model_out.parameterization.input_params()}
        # Solve inputs that depend on a function and were not saved
        # (we don't use the Parameterization_to_input method in case there are references
        #  to functions that cannot be loaded at the moment)
        for p, value in inputs.items():
            if value is None:
                func = dummy_model_out.parameterization._input_funcs[p]
                args = dummy_model_out.parameterization._input_args[p]
                inputs[p] = func(*[point.get(arg) for arg in args])
        # Add/remove priors
        priors_add = model_add.prior.logps(sampled)
        if not prior_recompute_1d:
            priors_add = priors_add[1:]
        logpriors_add = dict(zip(mlprior_names_add, priors_add))
        logpriors_new = [logpriors_add.get(name, - point.get(name, 0))
                         for name in collection_out.minuslogprior_names]
        if log.getEffectiveLevel() <= logging.DEBUG:
            log.debug(
                "New set of priors: %r", dict(zip(dummy_model_out.prior, logpriors_new)))
        if -np.inf in logpriors_new:
            continue
        # Add/remove likelihoods
        output_like = []
        if add[kinds.likelihood]:
            # Notice "one" (last in likelihood_add) is ignored: not in chi2_names
            loglikes_add, output_like = model_add.logps(inputs, return_derived=True)
            loglikes_add = dict(zip(chi2_names_add, loglikes_add))
            output_like = dict(zip(model_add.output_params, output_like))
        else:
            loglikes_add = dict()
        loglikes_new = [loglikes_add.get(name, -0.5 * point.get(name, 0))
                        for name in collection_out.chi2_names]
        if log.getEffectiveLevel() <= logging.DEBUG:
            log.debug(
                "New set of likelihoods: %r",
                dict(zip(dummy_model_out.likelihood, loglikes_new)))
            if output_like:
                log.debug("New set of likelihood-derived parameters: %r", output_like)
        if -np.inf in loglikes_new:
            continue
        # Add/remove derived parameters and change priors of sampled parameters
        for p in add[_params]:
            if p in dummy_model_out.parameterization._directly_output:
                derived[p] = output_like[p]
            elif p in dummy_model_out.parameterization._derived_funcs:
                func = dummy_model_out.parameterization._derived_funcs[p]
                args = dummy_model_out.parameterization._derived_args[p]
                derived[p] = func(
                    *[point.get(arg, output_like.get(arg, None)) for arg in args])
        # We need to recompute the aggregated chi2 by hand
        for type_, likes in inv_types.items():
            derived[_get_chi2_name(type_)] = sum(
                [-2 * lvalue for lname, lvalue
                 in zip(collection_out.chi2_names, loglikes_new)
                 if _undo_chi2_name(lname) in likes])
        if log.getEffectiveLevel() <= logging.DEBUG:
            log.debug("New derived parameters: %r",
                      dict([(p, derived[p])
                            for p in dummy_model_out.parameterization.derived_params()
                            if p in add[_params]]))
        # Save to the collection (keep old weight for now)
        collection_out.add(
            sampled, derived=derived.values(), weight=point.get(_weight),
            logpriors=logpriors_new, loglikes=loglikes_new)
        # Display progress
        percent = np.round(i / len(collection_in) * 100)
        if percent != last_percent and not percent % 5:
            last_percent = percent
            progress_bar(log, percent, " (%d/%d)" % (i, len(collection_in)))
    if not collection_out.data.last_valid_index():
        raise LoggedError(
            log, "No elements in the final sample. Possible causes: "
                 "added a prior or likelihood valued zero over the full sampled domain, "
                 "or the computation of the theory failed everywhere, etc.")
    # Reweight -- account for large dynamic range!
    #   Prefer to rescale +inf to finite, and ignore final points with -inf.
    #   Remove -inf's (0-weight), and correct indices
    difflogmax = max(collection_in[_minuslogpost] - collection_out[_minuslogpost])
    collection_out.data[_weight] *= np.exp(
        collection_in[_minuslogpost] - collection_out[_minuslogpost] - difflogmax)
    collection_out.data = (
        collection_out.data[collection_out.data.weight > 0].reset_index(drop=True))
    collection_out._n = collection_out.data.last_valid_index() + 1
    # Write!
    collection_out.out_update()
    log.info("Finished! Final number of samples: %d", len(collection_out))
    return info_out, {"sample": collection_out}
Пример #2
0
def post(info_or_yaml_or_file: Union[InputDict, str, os.PathLike],
         sample: Union[SampleCollection, List[SampleCollection], None] = None
         ) -> PostTuple:
    info = load_input_dict(info_or_yaml_or_file)
    logger_setup(info.get("debug"), info.get("debug_file"))
    log = get_logger(__name__)
    # MARKED FOR DEPRECATION IN v3.0
    if info.get("modules"):
        raise LoggedError(log, "The input field 'modules' has been deprecated."
                               "Please use instead %r", packages_path_input)
    # END OF DEPRECATION BLOCK
    info_post: PostDict = info.get("post") or {}
    if not info_post:
        raise LoggedError(log, "No 'post' block given. Nothing to do!")
    if mpi.is_main_process() and info.get("resume"):
        log.warning("Resuming not implemented for post-processing. Re-starting.")
    if not info.get("output") and info_post.get("output") \
            and not info.get("params"):
        raise LoggedError(log, "The input dictionary must have be a full option "
                               "dictionary, or have an existing 'output' root to load "
                               "previous settings from ('output' to read from is in the "
                               "main block not under 'post'). ")
    # 1. Load existing sample
    output_in = get_output(prefix=info.get("output"))
    if output_in:
        info_in = output_in.load_updated_info() or update_info(info)
    else:
        info_in = update_info(info)
    params_in: ExpandedParamsDict = info_in["params"]  # type: ignore
    dummy_model_in = DummyModel(params_in, info_in.get("likelihood", {}),
                                info_in.get("prior"))

    in_collections = []
    thin = info_post.get("thin", 1)
    skip = info_post.get("skip", 0)
    if info.get('thin') is not None or info.get('skip') is not None:  # type: ignore
        raise LoggedError(log, "'thin' and 'skip' should be "
                               "parameters of the 'post' block")

    if sample:
        # If MPI, assume for each MPI process post is passed in the list of
        # collections that should be processed by that process
        # (e.g. single chain output from sampler)
        if isinstance(sample, SampleCollection):
            in_collections = [sample]
        else:
            in_collections = sample
        for i, collection in enumerate(in_collections):
            if skip:
                if 0 < skip < 1:
                    skip = int(round(skip * len(collection)))
                collection = collection.filtered_copy(slice(skip, None))
            if thin != 1:
                collection = collection.thin_samples(thin)
            in_collections[i] = collection
    elif output_in:
        files = output_in.find_collections()
        numbered = files
        if not numbered:
            # look for un-numbered output files
            files = output_in.find_collections(name=False)
        if files:
            if mpi.size() > len(files):
                raise LoggedError(log, "Number of MPI processes (%s) is larger than "
                                       "the number of sample files (%s)",
                                  mpi.size(), len(files))
            for num in range(mpi.rank(), len(files), mpi.size()):
                in_collections += [SampleCollection(
                    dummy_model_in, output_in,
                    onload_thin=thin, onload_skip=skip, load=True, file_name=files[num],
                    name=str(num + 1) if numbered else "")]
        else:
            raise LoggedError(log, "No samples found for the input model with prefix %s",
                              os.path.join(output_in.folder, output_in.prefix))

    else:
        raise LoggedError(log, "No output from where to load from, "
                               "nor input collections given.")
    if any(len(c) <= 1 for c in in_collections):
        raise LoggedError(
            log, "Not enough samples for post-processing. Try using a larger sample, "
                 "or skipping or thinning less.")
    mpi.sync_processes()
    log.info("Will process %d sample points.", sum(len(c) for c in in_collections))

    # 2. Compare old and new info: determine what to do
    add = info_post.get("add") or {}
    if "remove" in add:
        raise LoggedError(log, "remove block should be under 'post', not 'add'")
    remove = info_post.get("remove") or {}
    # Add a dummy 'one' likelihood, to absorb unused parameters
    if not add.get("likelihood"):
        add["likelihood"] = {}
    add["likelihood"]["one"] = None
    # Expand the "add" info, but don't add new default sampled parameters
    orig_params = set(add.get("params") or [])
    add = update_info(add, add_aggr_chi2=False)
    add_params: ExpandedParamsDict = add["params"]  # type: ignore
    for p in set(add_params) - orig_params:
        if p in params_in:
            add_params.pop(p)

    # 2.1 Adding/removing derived parameters and changes in priors of sampled parameters
    out_combined_params = deepcopy_where_possible(params_in)
    remove_params = list(str_to_list(remove.get("params")) or [])
    for p in remove_params:
        pinfo = params_in.get(p)
        if pinfo is None or not is_derived_param(pinfo):
            raise LoggedError(
                log,
                "You tried to remove parameter '%s', which is not a derived parameter. "
                "Only derived parameters can be removed during post-processing.", p)
        out_combined_params.pop(p)
    # Force recomputation of aggregated chi2
    for p in list(out_combined_params):
        if p.startswith(get_chi2_name("")):
            out_combined_params.pop(p)
    prior_recompute_1d = False
    for p, pinfo in add_params.items():
        pinfo_in = params_in.get(p)
        if is_sampled_param(pinfo):
            if not is_sampled_param(pinfo_in):
                # No added sampled parameters (de-marginalisation not implemented)
                if pinfo_in is None:
                    raise LoggedError(
                        log, "You added a new sampled parameter %r (maybe accidentally "
                             "by adding a new likelihood that depends on it). "
                             "Adding new sampled parameters is not possible. Try fixing "
                             "it to some value.", p)
                else:
                    raise LoggedError(
                        log,
                        "You tried to change the prior of parameter '%s', "
                        "but it was not a sampled parameter. "
                        "To change that prior, you need to define as an external one.", p)
            # recompute prior if potentially changed sampled parameter priors
            prior_recompute_1d = True
        elif is_derived_param(pinfo):
            if p in out_combined_params:
                raise LoggedError(
                    log, "You tried to add derived parameter '%s', which is already "
                         "present. To force its recomputation, 'remove' it too.", p)
        elif is_fixed_or_function_param(pinfo):
            # Only one possibility left "fixed" parameter that was not present before:
            # input of new likelihood, or just an argument for dynamical derived (dropped)
            if pinfo_in and p in params_in and pinfo["value"] != pinfo_in.get("value"):
                raise LoggedError(
                    log,
                    "You tried to add a fixed parameter '%s: %r' that was already present"
                    " but had a different value or was not fixed. This is not allowed. "
                    "The old info of the parameter was '%s: %r'",
                    p, dict(pinfo), p, dict(pinfo_in))
        elif not pinfo_in:  # OK as long as we have known value for it
            raise LoggedError(log, "Parameter %s no known value. ", p)
        out_combined_params[p] = pinfo

    out_combined: InputDict = {"params": out_combined_params}  # type: ignore
    # Turn the rest of *derived* parameters into constants,
    # so that the likelihoods do not try to recompute them
    # But be careful to exclude *input* params that have a "derived: True" value
    # (which in "updated info" turns into "derived: 'lambda [x]: [x]'")
    # Don't assign to derived parameters to theories, only likelihoods, so they can be
    # recomputed if needed. If the theory does not need to be computed, it doesn't matter
    # if it is already assigned parameters in the usual way; likelihoods can get
    # the required derived parameters from the stored sample derived parameter inputs.
    out_params_with_computed = deepcopy_where_possible(out_combined_params)

    dropped_theory = set()
    for p, pinfo in out_params_with_computed.items():
        if (is_derived_param(pinfo) and "value" not in pinfo
                and p not in add_params):
            out_params_with_computed[p] = {"value": np.nan}
            dropped_theory.add(p)
    # 2.2 Manage adding/removing priors and likelihoods
    warn_remove = False
    kind: ModelBlock
    for kind in ("prior", "likelihood", "theory"):
        out_combined[kind] = deepcopy_where_possible(info_in.get(kind)) or {}
        for remove_item in str_to_list(remove.get(kind)) or []:
            try:
                out_combined[kind].pop(remove_item, None)
                if remove_item not in (add.get(kind) or []) and kind != "theory":
                    warn_remove = True
            except ValueError:
                raise LoggedError(
                    log, "Trying to remove %s '%s', but it is not present. "
                         "Existing ones: %r", kind, remove_item, list(out_combined[kind]))
        if kind != "theory" and kind in add:
            dups = set(add.get(kind) or []).intersection(out_combined[kind]) - {"one"}
            if dups:
                raise LoggedError(
                    log, "You have added %s '%s', which was already present. If you "
                         "want to force its recomputation, you must also 'remove' it.",
                    kind, dups)
            out_combined[kind].update(add[kind])

    if warn_remove and mpi.is_main_process():
        log.warning("You are removing a prior or likelihood pdf. "
                    "Notice that if the resulting posterior is much wider "
                    "than the original one, or displaced enough, "
                    "it is probably safer to explore it directly.")

    mlprior_names_add = minuslogprior_names(add.get("prior") or [])
    chi2_names_add = [get_chi2_name(name) for name in add["likelihood"] if
                      name != "one"]
    out_combined["likelihood"].pop("one", None)

    add_theory = add.get("theory")
    if add_theory:
        if len(add["likelihood"]) == 1 and not any(
                is_derived_param(pinfo) for pinfo in add_params.values()):
            log.warning("You are adding a theory, but this does not force recomputation "
                        "of any likelihood or derived parameters unless explicitly "
                        "removed+added.")
        # Inherit from the original chain (input|output_params, renames, etc)
        added_theory = add_theory.copy()
        for theory, theory_info in out_combined["theory"].items():
            if theory in list(added_theory):
                out_combined["theory"][theory] = \
                    recursive_update(theory_info, added_theory.pop(theory))
        out_combined["theory"].update(added_theory)

    # Prepare recomputation of aggregated chi2
    # (they need to be recomputed by hand, because auto-computation won't pick up
    #  old likelihoods for a given type)
    all_types = {like: str_to_list(opts.get("type") or [])
                 for like, opts in out_combined["likelihood"].items()}
    types = set(chain(*all_types.values()))
    inv_types = {t: [like for like, like_types in all_types.items() if t in like_types]
                 for t in sorted(types)}
    add_aggregated_chi2_params(out_combined_params, types)

    # 3. Create output collection
    # Use default prefix if it exists. If it does not, produce no output by default.
    # {post: {output: None}} suppresses output, and if it's a string, updates it.
    out_prefix = info_post.get("output", info.get("output"))
    if out_prefix:
        suffix = info_post.get("suffix")
        if not suffix:
            raise LoggedError(log, "You need to provide a '%s' for your output chains.",
                              "suffix")
        out_prefix += separator_files + "post" + separator_files + suffix
    output_out = get_output(prefix=out_prefix, force=info.get("force"))
    output_out.set_lock()

    if output_out and not output_out.force and output_out.find_collections():
        raise LoggedError(log, "Found existing post-processing output with prefix %r. "
                               "Delete it manually or re-run with `force: True` "
                               "(or `-f`, `--force` from the shell).", out_prefix)
    elif output_out and output_out.force and mpi.is_main_process():
        output_out.delete_infos()
        for _file in output_out.find_collections():
            output_out.delete_file_or_folder(_file)
    info_out = deepcopy_where_possible(info)
    info_post = info_post.copy()
    info_out["post"] = info_post
    # Updated with input info and extended (updated) add info
    info_out.update(info_in)  # type: ignore
    info_post["add"] = add

    dummy_model_out = DummyModel(out_combined_params, out_combined["likelihood"],
                                 info_prior=out_combined["prior"])
    out_func_parameterization = Parameterization(out_params_with_computed)

    # TODO: check allow_renames=False?
    model_add = Model(out_params_with_computed, add["likelihood"],
                      info_prior=add.get("prior"), info_theory=out_combined["theory"],
                      packages_path=(info_post.get(packages_path_input) or
                                     info.get(packages_path_input)),
                      allow_renames=False, post=True,
                      stop_at_error=info.get('stop_at_error', False),
                      skip_unused_theories=True, dropped_theory_params=dropped_theory)
    # Remove auxiliary "one" before dumping -- 'add' *is* info_out["post"]["add"]
    add["likelihood"].pop("one")
    out_collections = [SampleCollection(dummy_model_out, output_out, name=c.name,
                                        cache_size=OutputOptions.default_post_cache_size)
                       for c in in_collections]
    # TODO: should maybe add skip/thin to out_combined, so can tell post-processed?
    output_out.check_and_dump_info(info_out, out_combined, check_compatible=False)
    collection_in = in_collections[0]
    collection_out = out_collections[0]

    last_percent = None
    known_constants = dummy_model_out.parameterization.constant_params()
    known_constants.update(dummy_model_in.parameterization.constant_params())
    missing_params = dummy_model_in.parameterization.sampled_params().keys() - set(
        collection_in.columns)
    if missing_params:
        raise LoggedError(log, "Input samples do not contain expected sampled parameter "
                               "values: %s", missing_params)

    missing_priors = set(name for name in collection_out.minuslogprior_names if
                         name not in mlprior_names_add
                         and name not in collection_in.columns)
    if _minuslogprior_1d_name in missing_priors:
        prior_recompute_1d = True
    if prior_recompute_1d:
        missing_priors.discard(_minuslogprior_1d_name)
        mlprior_names_add.insert(0, _minuslogprior_1d_name)
    prior_regenerate: Optional[Prior]
    if missing_priors and "prior" in info_in:
        # in case there are input priors that are not stored in input samples
        # e.g. when postprocessing GetDist/CosmoMC-format chains
        in_names = minuslogprior_names(info_in["prior"])
        info_prior = {piname: inf for (piname, inf), in_name in
                      zip(info_in["prior"].items(), in_names) if
                      in_name in missing_priors}
        regenerated_prior_names = minuslogprior_names(info_prior)
        missing_priors.difference_update(regenerated_prior_names)
        prior_regenerate = Prior(dummy_model_in.parameterization, info_prior)
    else:
        prior_regenerate = None
        regenerated_prior_names = None
    if missing_priors:
        raise LoggedError(log, "Missing priors: %s", missing_priors)

    mpi.sync_processes()
    output_in.check_lock()

    # 4. Main loop! Loop over input samples and adjust as required.
    if mpi.is_main_process():
        log.info("Running post-processing...")
    difflogmax: Optional[float] = None
    to_do = sum(len(c) for c in in_collections)
    weights = []
    done = 0
    last_dump_time = time.time()
    for collection_in, collection_out in zip(in_collections, out_collections):
        importance_weights = []

        def set_difflogmax():
            nonlocal difflogmax
            difflog = (collection_in[OutPar.minuslogpost].to_numpy(
                dtype=np.float64)[:len(collection_out)]
                       - collection_out[OutPar.minuslogpost].to_numpy(dtype=np.float64))
            difflogmax = np.max(difflog)
            if abs(difflogmax) < 1:
                difflogmax = 0  # keep simple when e.g. very similar
            log.debug("difflogmax: %g", difflogmax)
            if mpi.more_than_one_process():
                difflogmax = max(mpi.allgather(difflogmax))
            if mpi.is_main_process():
                log.debug("Set difflogmax: %g", difflogmax)
            _weights = np.exp(difflog - difflogmax)
            importance_weights.extend(_weights)
            collection_out.reweight(_weights)

        for i, point in collection_in.data.iterrows():
            all_params = point.to_dict()
            for p in remove_params:
                all_params.pop(p, None)
            log.debug("Point: %r", point)
            sampled = np.array([all_params[param] for param in
                                dummy_model_in.parameterization.sampled_params()])
            all_params = out_func_parameterization.to_input(all_params).copy()

            # Add/remove priors
            if prior_recompute_1d:
                priors_add = [model_add.prior.logps_internal(sampled)]
                if priors_add[0] == -np.inf:
                    continue
            else:
                priors_add = []
            if model_add.prior.external:
                priors_add.extend(model_add.prior.logps_external(all_params))

            logpriors_add = dict(zip(mlprior_names_add, priors_add))
            logpriors_new = [logpriors_add.get(name, - point.get(name, 0))
                             for name in collection_out.minuslogprior_names]
            if prior_regenerate:
                regenerated = dict(zip(regenerated_prior_names,
                                       prior_regenerate.logps_external(all_params)))
                for _i, name in enumerate(collection_out.minuslogprior_names):
                    if name in regenerated_prior_names:
                        logpriors_new[_i] = regenerated[name]

            if is_debug(log):
                log.debug("New set of priors: %r",
                          dict(zip(dummy_model_out.prior, logpriors_new)))
            if -np.inf in logpriors_new:
                continue
            # Add/remove likelihoods and/or (re-)calculate derived parameters
            loglikes_add, output_derived = model_add._loglikes_input_params(
                all_params, return_output_params=True)
            loglikes_add = dict(zip(chi2_names_add, loglikes_add))
            output_derived = dict(zip(model_add.output_params, output_derived))
            loglikes_new = [loglikes_add.get(name, -0.5 * point.get(name, 0))
                            for name in collection_out.chi2_names]
            if is_debug(log):
                log.debug("New set of likelihoods: %r",
                          dict(zip(dummy_model_out.likelihood, loglikes_new)))
                if output_derived:
                    log.debug("New set of derived parameters: %r", output_derived)
            if -np.inf in loglikes_new:
                continue
            all_params.update(output_derived)

            all_params.update(out_func_parameterization.to_derived(all_params))
            derived = {param: all_params.get(param) for param in
                       dummy_model_out.parameterization.derived_params()}
            # We need to recompute the aggregated chi2 by hand
            for type_, likes in inv_types.items():
                derived[get_chi2_name(type_)] = sum(
                    -2 * lvalue for lname, lvalue
                    in zip(collection_out.chi2_names, loglikes_new)
                    if undo_chi2_name(lname) in likes)
            if is_debug(log):
                log.debug("New derived parameters: %r",
                          {p: derived[p]
                           for p in dummy_model_out.parameterization.derived_params()
                           if p in add["params"]})
            # Save to the collection (keep old weight for now)
            weight = point.get(OutPar.weight)
            mpi.check_errors()
            if difflogmax is None and i > OutputOptions.reweight_after and \
                    time.time() - last_dump_time > OutputOptions.output_inteveral_s / 2:
                set_difflogmax()
                collection_out.out_update()

            if difflogmax is not None:
                logpost_new = sum(logpriors_new) + sum(loglikes_new)
                importance_weight = np.exp(logpost_new + point.get(OutPar.minuslogpost)
                                           - difflogmax)
                weight = weight * importance_weight
                importance_weights.append(importance_weight)
                if time.time() - last_dump_time > OutputOptions.output_inteveral_s:
                    collection_out.out_update()
                    last_dump_time = time.time()

            if weight > 0:
                collection_out.add(sampled, derived=derived.values(), weight=weight,
                                   logpriors=logpriors_new, loglikes=loglikes_new)

            # Display progress
            percent = int(np.round((i + done) / to_do * 100))
            if percent != last_percent and not percent % 5:
                last_percent = percent
                progress_bar(log, percent, " (%d/%d)" % (i + done, to_do))

        if difflogmax is None:
            set_difflogmax()
        if not collection_out.data.last_valid_index():
            raise LoggedError(
                log, "No elements in the final sample. Possible causes: "
                     "added a prior or likelihood valued zero over the full sampled "
                     "domain, or the computation of the theory failed everywhere, etc.")
        collection_out.out_update()
        weights.append(np.array(importance_weights))
        done += len(collection_in)

    assert difflogmax is not None
    points = 0
    tot_weight = 0
    min_weight = np.inf
    max_weight = -np.inf
    max_output_weight = -np.inf
    sum_w2 = 0
    points_removed = 0
    for collection_in, collection_out, importance_weights in zip(in_collections,
                                                                 out_collections,
                                                                 weights):
        output_weights = collection_out[OutPar.weight]
        points += len(collection_out)
        tot_weight += np.sum(output_weights)
        points_removed += len(importance_weights) - len(output_weights)
        min_weight = min(min_weight, np.min(importance_weights))
        max_weight = max(max_weight, np.max(importance_weights))
        max_output_weight = max(max_output_weight, np.max(output_weights))
        sum_w2 += np.dot(output_weights, output_weights)

    (tot_weights, min_weights, max_weights, max_output_weights, sum_w2s, points_s,
     points_removed_s) = mpi.zip_gather(
        [tot_weight, min_weight, max_weight, max_output_weight, sum_w2,
         points, points_removed])

    if mpi.is_main_process():
        output_out.clear_lock()
        log.info("Finished! Final number of distinct sample points: %s", sum(points_s))
        log.info("Importance weight range: %.4g -- %.4g",
                 min(min_weights), max(max_weights))
        if sum(points_removed_s):
            log.info("Points deleted due to zero weight: %s", sum(points_removed_s))
        log.info("Effective number of single samples if independent (sum w)/max(w): %s",
                 int(sum(tot_weights) / max(max_output_weights)))
        log.info(
            "Effective number of weighted samples if independent (sum w)^2/sum(w^2): "
            "%s", int(sum(tot_weights) ** 2 / sum(sum_w2s)))
    products: PostResultDict = {"sample": value_or_list(out_collections),
                                "stats": {'min_importance_weight': (min(min_weights) /
                                                                    max(max_weights)),
                                          'points_removed': sum(points_removed_s),
                                          'tot_weight': sum(tot_weights),
                                          'max_weight': max(max_output_weights),
                                          'sum_w2': sum(sum_w2s),
                                          'points': sum(points_s)},
                                "logpost_weight_offset": difflogmax,
                                "weights": value_or_list(weights)}
    return PostTuple(info=out_combined, products=products)
Пример #3
0
def post(info, sample=None):
    logger_setup(info.get(_debug), info.get(_debug_file))
    log = logging.getLogger(__name__.split(".")[-1])
    try:
        info_post = info[_post]
    except KeyError:
        log.error("No 'post' block given. Nothing to do!")
        raise HandledException
    if get_mpi_rank():
        log.warning(
            "Post-processing is not yet MPI-able. Doing nothing for rank > 1 processes."
        )
        return
    # 1. Load existing sample
    output_in = Output(output_prefix=info.get(_output_prefix), resume=True)
    info_in = load_input(output_in.file_full) if output_in else deepcopy(info)
    dummy_model_in = DummyModel(info_in[_params], info_in[_likelihood],
                                info_in.get(_prior, None),
                                info_in.get(_theory, None))
    if output_in:
        i = 0
        while True:
            try:
                collection = Collection(dummy_model_in,
                                        output_in,
                                        name="%d" % (1 + i),
                                        load=True,
                                        onload_skip=info_post.get("skip", 0),
                                        onload_thin=info_post.get("thin", 1))
                if i == 0:
                    collection_in = collection
                else:
                    collection_in._append(collection)
                i += 1
            except IOError:
                break
    elif sample:
        if isinstance(sample, Collection):
            sample = [sample]
        collection_in = deepcopy(sample[0])
        for s in sample[1:]:
            try:
                collection_in._append(s)
            except:
                log.error("Failed to load some of the input samples.")
                raise HandledException
        i = len(sample)
    else:
        log.error(
            "Not output from where to load from or input collections given.")
        raise HandledException
    log.info("Loaded %d chain%s. Will process %d samples.", i,
             "s" if i - 1 else "", collection_in.n())
    if collection_in.n() <= 1:
        log.error(
            "Not enough samples for post-processing. Try using a larger sample, "
            "or skipping or thinning less.")
        raise HandledException
    # 2. Compare old and new info: determine what to do
    add = info_post.get("add", {})
    remove = info_post.get("remove", {})
    # Add a dummy 'one' likelihood, to absorb unused parameters
    if not add.get(_likelihood):
        add[_likelihood] = odict()
    add[_likelihood].update({"one": None})
    # Expand the "add" info
    add = get_full_info(add)
    # 2.1 Adding/removing derived parameters and changes in priors of sampled parameters
    out = {_params: deepcopy(info_in[_params])}
    for p in remove.get(_params, {}):
        pinfo = info_in[_params].get(p)
        if pinfo is None or not is_derived_param(pinfo):
            log.error(
                "You tried to remove parameter '%s', which is not a derived paramter. "
                "Only derived parameters can be removed during post-processing.",
                p)
            raise HandledException
        out[_params].pop(p)
    mlprior_names_add = []
    for p, pinfo in add.get(_params, {}).items():
        pinfo_in = info_in[_params].get(p)
        if is_sampled_param(pinfo):
            if not is_sampled_param(pinfo_in):
                # No added sampled parameters (de-marginalisation not implemented)
                if pinfo_in is None:
                    log.error(
                        "You added a new sampled parameter %r (maybe accidentaly "
                        "by adding a new likelihood that depends on it). "
                        "Adding new sampled parameters is not possible. Try fixing "
                        "it to some value.", p)
                    raise HandledException
                else:
                    log.error(
                        "You tried to change the prior of parameter '%s', "
                        "but it was not a sampled parameter. "
                        "To change that prior, you need to define as an external one.",
                        p)
                    raise HandledException
            if mlprior_names_add[:1] != _prior_1d_name:
                mlprior_names_add = (
                    [_minuslogprior + _separator + _prior_1d_name] +
                    mlprior_names_add)
        elif is_derived_param(pinfo):
            if p in out[_params]:
                log.error(
                    "You tried to add derived parameter '%s', which is already "
                    "present. To force its recomputation, 'remove' it too.", p)
                raise HandledException
        elif is_fixed_param(pinfo):
            # Only one possibility left "fixed" parameter that was not present before:
            # input of new likelihood, or just an argument for dynamical derived (dropped)
            if ((p in info_in[_params] and pinfo[_p_value] !=
                 (pinfo_in or {}).get(_p_value, None))):
                log.error(
                    "You tried to add a fixed parameter '%s: %r' that was already present"
                    " but had a different value or was not fixed. This is not allowed. "
                    "The old info of the parameter was '%s: %r'", p,
                    dict(pinfo), p, dict(pinfo_in))
                raise HandledException
        else:
            log.error("This should not happen. Contact the developers.")
            raise HandledException
        out[_params][p] = pinfo
    # For the likelihood only, turn the rest of *derived* parameters into constants,
    # so that the likelihoods do not try to compute them)
    # But be careful to exclude *input* params that have a "derived: True" value
    # (which in "full info" turns into "derived: 'lambda [x]: [x]'")
    out_params_like = deepcopy(out[_params])
    for p, pinfo in out_params_like.items():
        if ((is_derived_param(pinfo) and not (_p_value in pinfo)
             and p not in add.get(_params, {}))):
            out_params_like[p] = {_p_value: np.nan, _p_drop: True}
    parameterization_like = Parameterization(out_params_like,
                                             ignore_unused_sampled=True)
    # 2.2 Manage adding/removing priors and likelihoods
    warn_remove = False
    for level in [_prior, _likelihood]:
        out[level] = getattr(dummy_model_in, level)
        if level == _prior:
            out[level].remove(_prior_1d_name)
        for pdf in info_post.get("remove", {}).get(level, []) or []:
            try:
                out[level].remove(pdf)
                warn_remove = True
            except ValueError:
                log.error(
                    "Trying to remove %s '%s', but it is not present. "
                    "Existing ones: %r", level, pdf, out[level])
                raise HandledException
    if warn_remove:
        log.warning("You are removing a prior or likelihood pdf. "
                    "Notice that if the resulting posterior is much wider "
                    "than the original one, or displaced enough, "
                    "it is probably safer to explore it directly.")
    if _prior in add:
        mlprior_names_add += [
            _minuslogprior + _separator + name for name in add[_prior]
        ]
        out[_prior] += list(add[_prior])
    prior_recompute_1d = (mlprior_names_add[:1] == [
        _minuslogprior + _separator + _prior_1d_name
    ])
    # Don't initialise the theory code if not adding/recomputing theory,
    # theory-derived params or likelihoods
    recompute_theory = info_in.get(_theory) and not (list(
        add[_likelihood]) == ["one"] and not any([
            is_derived_param(pinfo) for pinfo in add.get(_params, {}).values()
        ]))
    if recompute_theory:
        # Inherit from the original chain (needs input|output_params, renames, etc
        theory = list(info_in[_theory].keys())[0]
        info_theory_out = odict([[
            theory,
            recursive_update(deepcopy(info_in[_theory][theory]),
                             add.get(_theory, {theory: {}})[theory])
        ]])
    else:
        info_theory_out = None
    chi2_names_add = [
        _chi2 + _separator + name for name in add[_likelihood]
        if name is not "one"
    ]
    out[_likelihood] += [l for l in add[_likelihood] if l is not "one"]
    if recompute_theory:
        log.warn(
            "You are recomputing the theory, but in the current version this does "
            "not force recomputation of any likelihood or derived parameter, "
            "unless explicitly removed+added.")
    for level in [_prior, _likelihood]:
        for i, x_i in enumerate(out[level]):
            if x_i in list(out[level])[i + 1:]:
                log.error(
                    "You have added %s '%s', which was already present. If you "
                    "want to force its recomputation, you must also 'remove' it.",
                    level, x_i)
                raise HandledException
    # 3. Create output collection
    if "suffix" not in info_post:
        log.error("You need to provide a 'suffix' for your chains.")
        raise HandledException
    # Use default prefix if it exists. If it does not, produce no output by default.
    # {post: {output: None}} suppresses output, and if it's a string, updates it.
    out_prefix = info_post.get(_output_prefix, info.get(_output_prefix))
    if out_prefix not in [None, False]:
        out_prefix += "_" + _post + "_" + info_post["suffix"]
    output_out = Output(output_prefix=out_prefix,
                        force_output=info.get(_force))
    info_out = deepcopy(info)
    info_out[_post] = info_post
    # Updated with input info and extended (full) add info
    info_out.update(info_in)
    info_out[_post]["add"] = add
    dummy_model_out = DummyModel(out[_params],
                                 out[_likelihood],
                                 info_prior=out[_prior])
    if recompute_theory:
        theory = list(info_theory_out.keys())[0]
        if _input_params not in info_theory_out[theory]:
            log.error(
                "You appear to be post-processing a chain generated with an older "
                "version of Cobaya. For post-processing to work, please edit the "
                "'[root]__full.info' file of the original chain to add, inside the "
                "theory code block, the list of its input parameters. E.g.\n----\n"
                "theory:\n  %s:\n    input_params: [param1, param2, ...]\n"
                "----\nIf you get strange errors later, it is likely that you did not "
                "specify the correct set of theory parameters.\n"
                "The full set of input parameters are %s.", theory,
                list(dummy_model_out.parameterization.input_params()))
            raise HandledException
    prior_add = Prior(dummy_model_out.parameterization, add.get(_prior))
    likelihood_add = Likelihood(add[_likelihood],
                                parameterization_like,
                                info_theory=info_theory_out,
                                modules=info.get(_path_install))
    # Remove auxiliary "one" before dumping -- 'add' *is* info_out[_post]["add"]
    add[_likelihood].pop("one")
    if likelihood_add.theory:
        # Make sure that theory.needs is called at least once, for adjustments
        likelihood_add.theory.needs()
    collection_out = Collection(dummy_model_out, output_out, name="1")
    output_out.dump_info({}, info_out)
    # 4. Main loop!
    log.info("Running post-processing...")
    last_percent = 0
    for i, point in enumerate(collection_in.data.itertuples()):
        log.debug("Point: %r", point)
        sampled = [
            getattr(point, param)
            for param in dummy_model_in.parameterization.sampled_params()
        ]
        derived = odict(
            [[param, getattr(point, param, None)]
             for param in dummy_model_out.parameterization.derived_params()])
        inputs = odict([[
            param,
            getattr(
                point, param,
                dummy_model_in.parameterization.constant_params().get(
                    param,
                    dummy_model_out.parameterization.constant_params().get(
                        param, None)))
        ] for param in dummy_model_out.parameterization.input_params()])
        # Solve inputs that depend on a function and were not saved
        # (we don't use the Parameterization_to_input method in case there are references
        #  to functions that cannot be loaded at the moment)
        for p, value in inputs.items():
            if value is None:
                func = dummy_model_out.parameterization._input_funcs[p]
                args = dummy_model_out.parameterization._input_args[p]
                inputs[p] = func(*[getattr(point, arg) for arg in args])
        # Add/remove priors
        priors_add = prior_add.logps(sampled)
        if not prior_recompute_1d:
            priors_add = priors_add[1:]
        logpriors_add = odict(zip(mlprior_names_add, priors_add))
        logpriors_new = [
            logpriors_add.get(name, -getattr(point, name, 0))
            for name in collection_out.minuslogprior_names
        ]
        if log.getEffectiveLevel() <= logging.DEBUG:
            log.debug("New set of priors: %r",
                      dict(zip(dummy_model_out.prior, logpriors_new)))
        if -np.inf in logpriors_new:
            continue
        # Add/remove likelihoods
        output_like = []
        if likelihood_add:
            # Notice "one" (last in likelihood_add) is ignored: not in chi2_names
            loglikes_add = odict(
                zip(chi2_names_add,
                    likelihood_add.logps(inputs, _derived=output_like)))
            output_like = dict(zip(likelihood_add.output_params, output_like))
        else:
            loglikes_add = dict()
        loglikes_new = [
            loglikes_add.get(name, -0.5 * getattr(point, name, 0))
            for name in collection_out.chi2_names
        ]
        if log.getEffectiveLevel() <= logging.DEBUG:
            log.debug("New set of likelihoods: %r",
                      dict(zip(dummy_model_out.likelihood, loglikes_new)))
            if output_like:
                log.debug("New set of likelihood-derived parameters: %r",
                          output_like)
        if -np.inf in loglikes_new:
            continue
        # Add/remove derived parameters and change priors of sampled parameters
        for p in add[_params]:
            if p in dummy_model_out.parameterization._directly_output:
                derived[p] = output_like[p]
            elif p in dummy_model_out.parameterization._derived_funcs:
                func = dummy_model_out.parameterization._derived_funcs[p]
                args = dummy_model_out.parameterization._derived_args[p]
                derived[p] = func(*[
                    getattr(point, arg, output_like.get(arg, None))
                    for arg in args
                ])
        if log.getEffectiveLevel() <= logging.DEBUG:
            log.debug(
                "New derived parameters: %r",
                dict([[
                    p, derived[p]
                ] for p in dummy_model_out.parameterization.derived_params()
                      if p in add[_params]]))
        # Save to the collection (keep old weight for now)
        collection_out.add(sampled,
                           derived=derived.values(),
                           weight=getattr(point, _weight),
                           logpriors=logpriors_new,
                           loglikes=loglikes_new)
        # Display progress
        percent = np.round(i / collection_in.n() * 100)
        if percent != last_percent and not percent % 5:
            last_percent = percent
            progress_bar(log, percent, " (%d/%d)" % (i, collection_in.n()))
    if not collection_out.data.last_valid_index():
        log.error(
            "No elements in the final sample. Possible causes: "
            "added a prior or likelihood valued zero over the full sampled domain, "
            "or the computation of the theory failed everywhere, etc.")
        raise HandledException
    # Reweight -- account for large dynamic range!
    #   Prefer to rescale +inf to finite, and ignore final points with -inf.
    #   Remove -inf's (0-weight), and correct indices
    difflogmax = max(collection_in[_minuslogpost] -
                     collection_out[_minuslogpost])
    collection_out.data[_weight] *= np.exp(collection_in[_minuslogpost] -
                                           collection_out[_minuslogpost] -
                                           difflogmax)
    collection_out.data = (
        collection_out.data[collection_out.data.weight > 0].reset_index(
            drop=True))
    collection_out._n = collection_out.data.last_valid_index() + 1
    # Write!
    collection_out._out_update()
    log.info("Finished! Final number of samples: %d", collection_out.n())
    return info_out, {"sample": collection_out}