from itertools import islice from typing import Any, Callable, Dict, Iterable, List, Optional from thinc.api import Config, Model from thinc.types import Floats2d from ..errors import Errors from ..language import Language from ..scorer import Scorer from ..tokens import Doc from ..training import Example, validate_get_examples from ..util import registry from ..vocab import Vocab from .textcat import TextCategorizer multi_label_default_config = """ [model] @architectures = "spacy.TextCatEnsemble.v2" [model.tok2vec] @architectures = "spacy.Tok2Vec.v2" [model.tok2vec.embed] @architectures = "spacy.MultiHashEmbed.v2" width = 64 rows = [2000, 2000, 500, 1000, 500] attrs = ["NORM", "LOWER", "PREFIX", "SUFFIX", "SHAPE"] include_static_vectors = false [model.tok2vec.encode] @architectures = "spacy.MaxoutWindowEncoder.v2" width = ${model.tok2vec.embed.width} window_size = 1 maxout_pieces = 3 depth = 2 [model.linear_model] @architectures = "spacy.TextCatBOW.v3" exclusive_classes = false length = 262144 ngram_size = 1 no_output_layer = false """ DEFAULT_MULTI_TEXTCAT_MODEL = Config().from_str(multi_label_default_config)["model"] multi_label_bow_config = """ [model] @architectures = "spacy.TextCatBOW.v3" exclusive_classes = false ngram_size = 1 no_output_layer = false """ multi_label_cnn_config = """ [model] @architectures = "spacy.TextCatReduce.v1" exclusive_classes = false use_reduce_first = false use_reduce_last = false use_reduce_max = false use_reduce_mean = true [model.tok2vec] @architectures = "spacy.HashEmbedCNN.v2" pretrained_vectors = null width = 96 depth = 4 embed_size = 2000 window_size = 1 maxout_pieces = 3 subword_features = true """ @Language.factory( "textcat_multilabel", assigns=["doc.cats"], default_config={ "threshold": 0.5, "model": DEFAULT_MULTI_TEXTCAT_MODEL, "scorer": {"@scorers": "spacy.textcat_multilabel_scorer.v2"}, }, default_score_weights={ "cats_score": 1.0, "cats_score_desc": None, "cats_micro_p": None, "cats_micro_r": None, "cats_micro_f": None, "cats_macro_p": None, "cats_macro_r": None, "cats_macro_f": None, "cats_macro_auc": None, "cats_f_per_type": None, }, ) def make_multilabel_textcat( nlp: Language, name: str, model: Model[List[Doc], List[Floats2d]], threshold: float, scorer: Optional[Callable], ) -> "MultiLabel_TextCategorizer": """Create a MultiLabel_TextCategorizer component. The text categorizer predicts categories over a whole document. It can learn one or more labels, and the labels are considered to be non-mutually exclusive, which means that there can be zero or more labels per doc). model (Model[List[Doc], List[Floats2d]]): A model instance that predicts scores for each category. threshold (float): Cutoff to consider a prediction "positive". scorer (Optional[Callable]): The scoring method. """ return MultiLabel_TextCategorizer( nlp.vocab, model, name, threshold=threshold, scorer=scorer ) def textcat_multilabel_score(examples: Iterable[Example], **kwargs) -> Dict[str, Any]: return Scorer.score_cats( examples, "cats", multi_label=True, **kwargs, ) @registry.scorers("spacy.textcat_multilabel_scorer.v2") def make_textcat_multilabel_scorer(): return textcat_multilabel_score class MultiLabel_TextCategorizer(TextCategorizer): """Pipeline component for multi-label text classification. DOCS: https://spacy.io/api/textcategorizer """ def __init__( self, vocab: Vocab, model: Model, name: str = "textcat_multilabel", *, threshold: float, scorer: Optional[Callable] = textcat_multilabel_score, ) -> None: """Initialize a text categorizer for multi-label classification. vocab (Vocab): The shared vocabulary. model (thinc.api.Model): The Thinc Model powering the pipeline component. name (str): The component instance name, used to add entries to the losses during training. threshold (float): Cutoff to consider a prediction "positive". scorer (Optional[Callable]): The scoring method. DOCS: https://spacy.io/api/textcategorizer#init """ self.vocab = vocab self.model = model self.name = name self._rehearsal_model = None cfg = {"labels": [], "threshold": threshold} self.cfg = dict(cfg) self.scorer = scorer @property def support_missing_values(self): return True def initialize( # type: ignore[override] self, get_examples: Callable[[], Iterable[Example]], *, nlp: Optional[Language] = None, labels: Optional[Iterable[str]] = None, ): """Initialize the pipe for training, using a representative set of data examples. get_examples (Callable[[], Iterable[Example]]): Function that returns a representative sample of gold-standard Example objects. nlp (Language): The current nlp object the component is part of. labels: The labels to add to the component, typically generated by the `init labels` command. If no labels are provided, the get_examples callback is used to extract the labels from the data. DOCS: https://spacy.io/api/textcategorizer#initialize """ validate_get_examples(get_examples, "MultiLabel_TextCategorizer.initialize") if labels is None: for example in get_examples(): for cat in example.y.cats: self.add_label(cat) else: for label in labels: self.add_label(label) subbatch = list(islice(get_examples(), 10)) self._validate_categories(subbatch) doc_sample = [eg.reference for eg in subbatch] label_sample, _ = self._examples_to_truth(subbatch) self._require_labels() assert len(doc_sample) > 0, Errors.E923.format(name=self.name) assert len(label_sample) > 0, Errors.E923.format(name=self.name) self.model.initialize(X=doc_sample, Y=label_sample) def _validate_categories(self, examples: Iterable[Example]): """This component allows any type of single- or multi-label annotations. This method overwrites the more strict one from 'textcat'.""" # check that annotation values are valid for ex in examples: for val in ex.reference.cats.values(): if not (val == 1.0 or val == 0.0): raise ValueError(Errors.E851.format(val=val))