Exemple #1
0
    def extend_from_instances(self,
                              params: Params,
                              instances: Iterable['adi.Instance'] = ()) -> None:
        """
        Extends an already generated vocabulary using a collection of instances.
        """
        min_count = params.pop("min_count", None)
        max_vocab_size = pop_max_vocab_size(params)
        non_padded_namespaces = params.pop("non_padded_namespaces", DEFAULT_NON_PADDED_NAMESPACES)
        pretrained_files = params.pop("pretrained_files", {})
        min_pretrained_embeddings = params.pop("min_pretrained_embeddings", None)
        only_include_pretrained_words = params.pop_bool("only_include_pretrained_words", False)
        tokens_to_add = params.pop("tokens_to_add", None)
        params.assert_empty("Vocabulary - from dataset")

        logger.info("Fitting token dictionary from dataset.")
        namespace_token_counts: Dict[str, Dict[str, int]] = defaultdict(lambda: defaultdict(int))
        for instance in Tqdm.tqdm(instances):
            instance.count_vocab_items(namespace_token_counts)
        self._extend(counter=namespace_token_counts,
                     min_count=min_count,
                     max_vocab_size=max_vocab_size,
                     non_padded_namespaces=non_padded_namespaces,
                     pretrained_files=pretrained_files,
                     only_include_pretrained_words=only_include_pretrained_words,
                     tokens_to_add=tokens_to_add,
                     min_pretrained_embeddings=min_pretrained_embeddings)
 def from_params(
         cls, vocab: Vocabulary,
         params: Params) -> 'TokenCharactersEncoder':  # type: ignore
     # pylint: disable=arguments-differ
     embedding_params: Params = params.pop("embedding")
     # Embedding.from_params() uses "tokens" as the default namespace, but we need to change
     # that to be "token_characters" by default.
     embedding_params.setdefault("vocab_namespace", "token_characters")
     embedding = Embedding.from_params(vocab, embedding_params)
     encoder_params: Params = params.pop("encoder")
     encoder = Seq2VecEncoder.from_params(encoder_params)
     dropout = params.pop_float("dropout", 0.0)
     params.assert_empty(cls.__name__)
     return cls(embedding, encoder, dropout)
Exemple #3
0
    def from_params(
            cls, vocab: Vocabulary,
            params: Params) -> 'BasicTextFieldEmbedder':  # type: ignore
        # pylint: disable=arguments-differ,bad-super-call

        # The original `from_params` for this class was designed in a way that didn't agree
        # with the constructor. The constructor wants a 'token_embedders' parameter that is a
        # `Dict[str, TokenEmbedder]`, but the original `from_params` implementation expected those
        # key-value pairs to be top-level in the params object.
        #
        # This breaks our 'configuration wizard' and configuration checks. Hence, going forward,
        # the params need a 'token_embedders' key so that they line up with what the constructor wants.
        # For now, the old behavior is still supported, but produces a DeprecationWarning.

        embedder_to_indexer_map = params.pop("embedder_to_indexer_map", None)
        if embedder_to_indexer_map is not None:
            embedder_to_indexer_map = embedder_to_indexer_map.as_dict(
                quiet=True)
        allow_unmatched_keys = bool(params.pop("allow_unmatched_keys", False))

        token_embedder_params = params.pop('token_embedders', None)

        if token_embedder_params is not None:
            # New way: explicitly specified, so use it.
            token_embedders = {
                name: Embedding.from_params(vocab=vocab, params=subparams)
                for name, subparams in token_embedder_params.items()
            }

        else:
            # Warn that the original behavior is deprecated
            warnings.warn(
                DeprecationWarning(
                    "the token embedders for BasicTextFieldEmbedder should now "
                    "be specified as a dict under the 'token_embedders' key, "
                    "not as top-level key-value pairs"))

            token_embedders = {}
            keys = list(params.keys())
            for key in keys:
                embedder_params = params.pop(key)
                token_embedders[key] = Embedding.from_params(
                    vocab=vocab, params=embedder_params)

        # TODO(pitrack): replace this line?
        # params.assert_empty(cls.__name__)
        return cls(token_embedders, embedder_to_indexer_map,
                   allow_unmatched_keys)
Exemple #4
0
def pop_max_vocab_size(params: Params) -> Union[int, Dict[str, int]]:
    """
    max_vocab_size is allowed to be either an int or a Dict[str, int] (or nothing).
    But it could also be a string representing an int (in the case of environment variable
    substitution). So we need some complex logic to handle it.
    """
    size = params.pop("max_vocab_size", None)

    if isinstance(size, Params):
        # This is the Dict[str, int] case.
        return size.as_dict()
    elif size is not None:
        # This is the int / str case.
        try:
            return int(size)
        except:
            return size
    else:
        return None
Exemple #5
0
def create_kwargs(cls: Type[T], params: Params, **extras) -> Dict[str, Any]:
    """
    Given some class, a `Params` object, and potentially other keyword arguments,
    create a dict of keyword args suitable for passing to the class's constructor.

    The function does this by finding the class's constructor, matching the constructor
    arguments to entries in the `params` object, and instantiating values for the parameters
    using the type annotation and possibly a from_params method.

    Any values that are provided in the `extras` will just be used as is.
    For instance, you might provide an existing `Vocabulary` this way.
    """
    # Get the signature of the constructor.
    signature = inspect.signature(cls.__init__)
    kwargs: Dict[str, Any] = {}

    # Iterate over all the constructor parameters and their annotations.
    for name, param in signature.parameters.items():
        # Skip "self". You're not *required* to call the first parameter "self",
        # so in theory this logic is fragile, but if you don't call the self parameter
        # "self" you kind of deserve what happens.
        if name == "self":
            continue

        # If the annotation is a compound type like typing.Dict[str, int],
        # it will have an __origin__ field indicating `typing.Dict`
        # and an __args__ field indicating `(str, int)`. We capture both.
        annotation = remove_optional(param.annotation)
        origin = getattr(annotation, '__origin__', None)
        args = getattr(annotation, '__args__', [])

        # The parameter is optional if its default value is not the "no default" sentinel.
        default = param.default
        optional = default != _NO_DEFAULT

        # Some constructors expect extra non-parameter items, e.g. vocab: Vocabulary.
        # We check the provided `extras` for these and just use them if they exist.
        if name in extras:
            kwargs[name] = extras[name]

        # The next case is when the parameter type is itself constructible from_params.
        elif hasattr(annotation, 'from_params'):
            if name in params:
                # Our params have an entry for this, so we use that.
                subparams = params.pop(name)

                if takes_arg(annotation.from_params, 'extras'):
                    # If annotation.params accepts **extras, we need to pass them all along.
                    # For example, `BasicTextFieldEmbedder.from_params` requires a Vocabulary
                    # object, but `TextFieldEmbedder.from_params` does not.
                    subextras = extras
                else:
                    # Otherwise, only supply the ones that are actual args; any additional ones
                    # will cause a TypeError.
                    subextras = {
                        k: v
                        for k, v in extras.items()
                        if takes_arg(annotation.from_params, k)
                    }

                # In some cases we allow a string instead of a param dict, so
                # we need to handle that case separately.
                if isinstance(subparams, str):
                    kwargs[name] = annotation.by_name(subparams)()
                else:
                    kwargs[name] = annotation.from_params(params=subparams,
                                                          **subextras)
            elif not optional:
                # Not optional and not supplied, that's an error!
                raise ConfigurationError(
                    f"expected key {name} for {cls.__name__}")
            else:
                kwargs[name] = default

        # If the parameter type is a Python primitive, just pop it off
        # using the correct casting pop_xyz operation.
        elif annotation == str:
            kwargs[name] = (params.pop(name, default)
                            if optional else params.pop(name))
        elif annotation == int:
            kwargs[name] = (params.pop_int(name, default)
                            if optional else params.pop_int(name))
        elif annotation == bool:
            kwargs[name] = (params.pop_bool(name, default)
                            if optional else params.pop_bool(name))
        elif annotation == float:
            kwargs[name] = (params.pop_float(name, default)
                            if optional else params.pop_float(name))

        # This is special logic for handling types like Dict[str, TokenIndexer], which it creates by
        # instantiating each value from_params and returning the resulting dict.
        elif origin in (Dict, dict) and len(args) == 2 and hasattr(
                args[-1], 'from_params'):
            value_cls = annotation.__args__[-1]

            value_dict = {}

            for key, value_params in params.pop(name, Params({})).items():
                value_dict[key] = value_cls.from_params(params=value_params,
                                                        **extras)

            kwargs[name] = value_dict

        else:
            # Pass it on as is and hope for the best.   ¯\_(ツ)_/¯
            if optional:
                kwargs[name] = params.pop(name, default)
            else:
                kwargs[name] = params.pop(name)

    params.assert_empty(cls.__name__)
    return kwargs
Exemple #6
0
    def from_params(cls, params: Params, instances: Iterable['adi.Instance'] = None):  # type: ignore
        """
        There are two possible ways to build a vocabulary; from a
        collection of instances, using :func:`Vocabulary.from_instances`, or
        from a pre-saved vocabulary, using :func:`Vocabulary.from_files`.
        You can also extend pre-saved vocabulary with collection of instances
        using this method. This method wraps these options, allowing their
        specification from a ``Params`` object, generated from a JSON
        configuration file.

        Parameters
        ----------
        params: Params, required.
        instances: Iterable['adi.Instance'], optional
            If ``params`` doesn't contain a ``directory_path`` key,
            the ``Vocabulary`` can be built directly from a collection of
            instances (i.e. a dataset). If ``extend`` key is set False,
            dataset instances will be ignored and final vocabulary will be
            one loaded from ``directory_path``. If ``extend`` key is set True,
            dataset instances will be used to extend the vocabulary loaded
            from ``directory_path`` and that will be final vocabulary used.

        Returns
        -------
        A ``Vocabulary``.
        """
        # pylint: disable=arguments-differ
        # Vocabulary is ``Registrable`` so that you can configure a custom subclass,
        # but (unlike most of our registrables) almost everyone will want to use the
        # base implementation. So instead of having an abstract ``VocabularyBase`` or
        # such, we just add the logic for instantiating a registered subclass here,
        # so that most users can continue doing what they were doing.
        vocab_type = params.pop("type", None)
        if vocab_type is not None:
            return cls.by_name(vocab_type).from_params(params=params, instances=instances)

        extend = params.pop("extend", False)
        vocabulary_directory = params.pop("directory_path", None)
        if not vocabulary_directory and not instances:
            raise ConfigurationError("You must provide either a Params object containing a "
                                     "vocab_directory key or a Dataset to build a vocabulary from.")
        if extend and not instances:
            raise ConfigurationError("'extend' is true but there are not instances passed to extend.")
        if extend and not vocabulary_directory:
            raise ConfigurationError("'extend' is true but there is not 'directory_path' to extend from.")

        if vocabulary_directory and instances:
            if extend:
                logger.info("Loading Vocab from files and extending it with dataset.")
            else:
                logger.info("Loading Vocab from files instead of dataset.")

        if vocabulary_directory:
            vocab = Vocabulary.from_files(vocabulary_directory)
            if not extend:
                params.assert_empty("Vocabulary - from files")
                return vocab
        if extend:
            vocab.extend_from_instances(params, instances=instances)
            return vocab
        min_count = params.pop("min_count", None)
        max_vocab_size = pop_max_vocab_size(params)
        non_padded_namespaces = params.pop("non_padded_namespaces", DEFAULT_NON_PADDED_NAMESPACES)
        pretrained_files = params.pop("pretrained_files", {})
        min_pretrained_embeddings = params.pop("min_pretrained_embeddings", None)
        only_include_pretrained_words = params.pop_bool("only_include_pretrained_words", False)
        tokens_to_add = params.pop("tokens_to_add", None)
        params.assert_empty("Vocabulary - from dataset")
        return Vocabulary.from_instances(instances=instances,
                                         min_count=min_count,
                                         max_vocab_size=max_vocab_size,
                                         non_padded_namespaces=non_padded_namespaces,
                                         pretrained_files=pretrained_files,
                                         only_include_pretrained_words=only_include_pretrained_words,
                                         tokens_to_add=tokens_to_add,
                                         min_pretrained_embeddings=min_pretrained_embeddings)