# cython: profile=True # coding: utf8 from __future__ import unicode_literals, print_function import re import random import numpy import tempfile import shutil import itertools from pathlib import Path import srsly from . import _align from .syntax import nonproj from .tokens import Doc, Span from .errors import Errors from .compat import path2str from . import util from .util import minibatch, itershuffle from libc.stdio cimport FILE, fopen, fclose, fread, fwrite, feof, fseek punct_re = re.compile(r"\W") def tags_to_entities(tags): entities = [] start = None for i, tag in enumerate(tags): if tag is None: continue if tag.startswith("O"): # TODO: We shouldn't be getting these malformed inputs. Fix this. if start is not None: start = None continue elif tag == "-": continue elif tag.startswith("I"): if start is None: raise ValueError(Errors.E067.format(tags=tags[:i + 1])) continue if tag.startswith("U"): entities.append((tag[2:], i, i)) elif tag.startswith("B"): start = i elif tag.startswith("L"): entities.append((tag[2:], start, i)) start = None else: raise ValueError(Errors.E068.format(tag=tag)) return entities def merge_sents(sents): m_deps = [[], [], [], [], [], []] m_brackets = [] m_cats = sents.pop() i = 0 for (ids, words, tags, heads, labels, ner), brackets in sents: m_deps[0].extend(id_ + i for id_ in ids) m_deps[1].extend(words) m_deps[2].extend(tags) m_deps[3].extend(head + i for head in heads) m_deps[4].extend(labels) m_deps[5].extend(ner) m_brackets.extend((b["first"] + i, b["last"] + i, b["label"]) for b in brackets) i += len(ids) m_deps.append(m_cats) return [(m_deps, m_brackets)] def align(tokens_a, tokens_b): """Calculate alignment tables between two tokenizations, using the Levenshtein algorithm. The alignment is case-insensitive. tokens_a (List[str]): The candidate tokenization. tokens_b (List[str]): The reference tokenization. RETURNS: (tuple): A 5-tuple consisting of the following information: * cost (int): The number of misaligned tokens. * a2b (List[int]): Mapping of indices in `tokens_a` to indices in `tokens_b`. For instance, if `a2b[4] == 6`, that means that `tokens_a[4]` aligns to `tokens_b[6]`. If there's no one-to-one alignment for a token, it has the value -1. * b2a (List[int]): The same as `a2b`, but mapping the other direction. * a2b_multi (Dict[int, int]): A dictionary mapping indices in `tokens_a` to indices in `tokens_b`, where multiple tokens of `tokens_a` align to the same token of `tokens_b`. * b2a_multi (Dict[int, int]): As with `a2b_multi`, but mapping the other direction. """ if tokens_a == tokens_b: alignment = numpy.arange(len(tokens_a)) return 0, alignment, alignment, {}, {} tokens_a = [w.replace(" ", "").lower() for w in tokens_a] tokens_b = [w.replace(" ", "").lower() for w in tokens_b] cost, i2j, j2i, matrix = _align.align(tokens_a, tokens_b) i2j_multi, j2i_multi = _align.multi_align(i2j, j2i, [len(w) for w in tokens_a], [len(w) for w in tokens_b]) for i, j in list(i2j_multi.items()): if i2j_multi.get(i+1) != j and i2j_multi.get(i-1) != j: i2j[i] = j i2j_multi.pop(i) for j, i in list(j2i_multi.items()): if j2i_multi.get(j+1) != i and j2i_multi.get(j-1) != i: j2i[j] = i j2i_multi.pop(j) return cost, i2j, j2i, i2j_multi, j2i_multi class GoldCorpus(object): """An annotated corpus, using the JSON file format. Manages annotations for tagging, dependency parsing and NER. DOCS: https://spacy.io/api/goldcorpus """ def __init__(self, train, dev, gold_preproc=False, limit=None): """Create a GoldCorpus. train_path (unicode or Path): File or directory of training data. dev_path (unicode or Path): File or directory of development data. RETURNS (GoldCorpus): The newly created object. """ self.limit = limit if isinstance(train, str) or isinstance(train, Path): train = self.read_tuples(self.walk_corpus(train)) dev = self.read_tuples(self.walk_corpus(dev)) # Write temp directory with one doc per file, so we can shuffle and stream self.tmp_dir = Path(tempfile.mkdtemp()) self.write_msgpack(self.tmp_dir / "train", train, limit=self.limit) self.write_msgpack(self.tmp_dir / "dev", dev, limit=self.limit) def __del__(self): shutil.rmtree(path2str(self.tmp_dir)) @staticmethod def write_msgpack(directory, doc_tuples, limit=0): if not directory.exists(): directory.mkdir() n = 0 for i, doc_tuple in enumerate(doc_tuples): srsly.write_msgpack(directory / "{}.msg".format(i), [doc_tuple]) n += len(doc_tuple[1]) if limit and n >= limit: break @staticmethod def walk_corpus(path): path = util.ensure_path(path) if not path.is_dir(): return [path] paths = [path] locs = [] seen = set() for path in paths: if str(path) in seen: continue seen.add(str(path)) if path.parts[-1].startswith("."): continue elif path.is_dir(): paths.extend(path.iterdir()) elif path.parts[-1].endswith((".json", ".jsonl")): locs.append(path) return locs @staticmethod def read_tuples(locs, limit=0): i = 0 for loc in locs: loc = util.ensure_path(loc) if loc.parts[-1].endswith("json"): gold_tuples = read_json_file(loc) elif loc.parts[-1].endswith("jsonl"): gold_tuples = srsly.read_jsonl(loc) elif loc.parts[-1].endswith("msg"): gold_tuples = srsly.read_msgpack(loc) else: supported = ("json", "jsonl", "msg") raise ValueError(Errors.E124.format(path=path2str(loc), formats=supported)) for item in gold_tuples: yield item i += len(item[1]) if limit and i >= limit: return @property def dev_tuples(self): locs = (self.tmp_dir / "dev").iterdir() yield from self.read_tuples(locs, limit=self.limit) @property def train_tuples(self): locs = (self.tmp_dir / "train").iterdir() yield from self.read_tuples(locs, limit=self.limit) def count_train(self): n = 0 i = 0 for raw_text, paragraph_tuples in self.train_tuples: cats = paragraph_tuples.pop() for sent_tuples, brackets in paragraph_tuples: n += len(sent_tuples[1]) if self.limit and i >= self.limit: break i += 1 return n def train_docs(self, nlp, gold_preproc=False, max_length=None, noise_level=0.0, orth_variant_level=0.0): locs = list((self.tmp_dir / 'train').iterdir()) random.shuffle(locs) train_tuples = self.read_tuples(locs, limit=self.limit) gold_docs = self.iter_gold_docs(nlp, train_tuples, gold_preproc, max_length=max_length, noise_level=noise_level, orth_variant_level=orth_variant_level, make_projective=True) yield from gold_docs def train_docs_without_preprocessing(self, nlp, gold_preproc=False): gold_docs = self.iter_gold_docs(nlp, self.train_tuples, gold_preproc=gold_preproc) yield from gold_docs def dev_docs(self, nlp, gold_preproc=False): gold_docs = self.iter_gold_docs(nlp, self.dev_tuples, gold_preproc=gold_preproc) yield from gold_docs @classmethod def iter_gold_docs(cls, nlp, tuples, gold_preproc, max_length=None, noise_level=0.0, orth_variant_level=0.0, make_projective=False): for raw_text, paragraph_tuples in tuples: if gold_preproc: raw_text = None else: paragraph_tuples = merge_sents(paragraph_tuples) docs, paragraph_tuples = cls._make_docs(nlp, raw_text, paragraph_tuples, gold_preproc, noise_level=noise_level, orth_variant_level=orth_variant_level) golds = cls._make_golds(docs, paragraph_tuples, make_projective) for doc, gold in zip(docs, golds): if (not max_length) or len(doc) < max_length: yield doc, gold @classmethod def _make_docs(cls, nlp, raw_text, paragraph_tuples, gold_preproc, noise_level=0.0, orth_variant_level=0.0): if raw_text is not None: raw_text, paragraph_tuples = make_orth_variants(nlp, raw_text, paragraph_tuples, orth_variant_level=orth_variant_level) raw_text = add_noise(raw_text, noise_level) return [nlp.make_doc(raw_text)], paragraph_tuples else: docs = [] raw_text, paragraph_tuples = make_orth_variants(nlp, None, paragraph_tuples, orth_variant_level=orth_variant_level) return [Doc(nlp.vocab, words=add_noise(sent_tuples[1], noise_level)) for (sent_tuples, brackets) in paragraph_tuples], paragraph_tuples @classmethod def _make_golds(cls, docs, paragraph_tuples, make_projective): if len(docs) != len(paragraph_tuples): n_annots = len(paragraph_tuples) raise ValueError(Errors.E070.format(n_docs=len(docs), n_annots=n_annots)) return [GoldParse.from_annot_tuples(doc, sent_tuples, make_projective=make_projective) for doc, (sent_tuples, brackets) in zip(docs, paragraph_tuples)] def make_orth_variants(nlp, raw, paragraph_tuples, orth_variant_level=0.0): if random.random() >= orth_variant_level: return raw, paragraph_tuples if random.random() >= 0.5: lower = True if raw is not None: raw = raw.lower() ndsv = nlp.Defaults.single_orth_variants ndpv = nlp.Defaults.paired_orth_variants # modify words in paragraph_tuples variant_paragraph_tuples = [] for sent_tuples, brackets in paragraph_tuples: ids, words, tags, heads, labels, ner, cats = sent_tuples if lower: words = [w.lower() for w in words] # single variants punct_choices = [random.choice(x["variants"]) for x in ndsv] for word_idx in range(len(words)): for punct_idx in range(len(ndsv)): if tags[word_idx] in ndsv[punct_idx]["tags"] \ and words[word_idx] in ndsv[punct_idx]["variants"]: words[word_idx] = punct_choices[punct_idx] # paired variants punct_choices = [random.choice(x["variants"]) for x in ndpv] for word_idx in range(len(words)): for punct_idx in range(len(ndpv)): if tags[word_idx] in ndpv[punct_idx]["tags"] \ and words[word_idx] in itertools.chain.from_iterable(ndpv[punct_idx]["variants"]): # backup option: random left vs. right from pair pair_idx = random.choice([0, 1]) # best option: rely on paired POS tags like `` / '' if len(ndpv[punct_idx]["tags"]) == 2: pair_idx = ndpv[punct_idx]["tags"].index(tags[word_idx]) # next best option: rely on position in variants # (may not be unambiguous, so order of variants matters) else: for pair in ndpv[punct_idx]["variants"]: if words[word_idx] in pair: pair_idx = pair.index(words[word_idx]) words[word_idx] = punct_choices[punct_idx][pair_idx] variant_paragraph_tuples.append(((ids, words, tags, heads, labels, ner, cats), brackets)) # modify raw to match variant_paragraph_tuples if raw is not None: variants = [] for single_variants in ndsv: variants.extend(single_variants["variants"]) for paired_variants in ndpv: variants.extend(list(itertools.chain.from_iterable(paired_variants["variants"]))) # store variants in reverse length order to be able to prioritize # longer matches (e.g., "---" before "--") variants = sorted(variants, key=lambda x: len(x)) variants.reverse() variant_raw = "" raw_idx = 0 # add initial whitespace while raw_idx < len(raw) and re.match("\s", raw[raw_idx]): variant_raw += raw[raw_idx] raw_idx += 1 for sent_tuples, brackets in variant_paragraph_tuples: ids, words, tags, heads, labels, ner, cats = sent_tuples for word in words: match_found = False # add identical word if word not in variants and raw[raw_idx:].startswith(word): variant_raw += word raw_idx += len(word) match_found = True # add variant word else: for variant in variants: if not match_found and \ raw[raw_idx:].startswith(variant): raw_idx += len(variant) variant_raw += word match_found = True # something went wrong, abort # (add a warning message?) if not match_found: return raw, paragraph_tuples # add following whitespace while raw_idx < len(raw) and re.match("\s", raw[raw_idx]): variant_raw += raw[raw_idx] raw_idx += 1 return variant_raw, variant_paragraph_tuples return raw, variant_paragraph_tuples def add_noise(orig, noise_level): if random.random() >= noise_level: return orig elif type(orig) == list: corrupted = [_corrupt(word, noise_level) for word in orig] corrupted = [w for w in corrupted if w] return corrupted else: return "".join(_corrupt(c, noise_level) for c in orig) def _corrupt(c, noise_level): if random.random() >= noise_level: return c elif c in [".", "'", "!", "?", ","]: return "\n" else: return c.lower() def read_json_object(json_corpus_section): """Take a list of JSON-formatted documents (e.g. from an already loaded training data file) and yield tuples in the GoldParse format. json_corpus_section (list): The data. YIELDS (tuple): The reformatted data. """ for json_doc in json_corpus_section: tuple_doc = json_to_tuple(json_doc) for tuple_paragraph in tuple_doc: yield tuple_paragraph def json_to_tuple(doc): """Convert an item in the JSON-formatted training data to the tuple format used by GoldParse. doc (dict): One entry in the training data. YIELDS (tuple): The reformatted data. """ paragraphs = [] for paragraph in doc["paragraphs"]: sents = [] for sent in paragraph["sentences"]: words = [] ids = [] tags = [] heads = [] labels = [] ner = [] for i, token in enumerate(sent["tokens"]): words.append(token["orth"]) ids.append(i) tags.append(token.get('tag', "-")) heads.append(token.get("head", 0) + i) labels.append(token.get("dep", "")) # Ensure ROOT label is case-insensitive if labels[-1].lower() == "root": labels[-1] = "ROOT" ner.append(token.get("ner", "-")) sents.append([ [ids, words, tags, heads, labels, ner], sent.get("brackets", [])]) cats = {} for cat in paragraph.get("cats", {}): cats[cat["label"]] = cat["value"] sents.append(cats) if sents: yield [paragraph.get("raw", None), sents] def read_json_file(loc, docs_filter=None, limit=None): loc = util.ensure_path(loc) if loc.is_dir(): for filename in loc.iterdir(): yield from read_json_file(loc / filename, limit=limit) else: for doc in _json_iterate(loc): if docs_filter is not None and not docs_filter(doc): continue for json_tuple in json_to_tuple(doc): yield json_tuple def _json_iterate(loc): # We should've made these files jsonl...But since we didn't, parse out # the docs one-by-one to reduce memory usage. # It's okay to read in the whole file -- just don't parse it into JSON. cdef bytes py_raw loc = util.ensure_path(loc) with loc.open("rb") as file_: py_raw = file_.read() raw = py_raw cdef int square_depth = 0 cdef int curly_depth = 0 cdef int inside_string = 0 cdef int escape = 0 cdef int start = -1 cdef char c cdef char quote = ord('"') cdef char backslash = ord("\\") cdef char open_square = ord("[") cdef char close_square = ord("]") cdef char open_curly = ord("{") cdef char close_curly = ord("}") for i in range(len(py_raw)): c = raw[i] if escape: escape = False continue if c == backslash: escape = True continue if c == quote: inside_string = not inside_string continue if inside_string: continue if c == open_square: square_depth += 1 elif c == close_square: square_depth -= 1 elif c == open_curly: if square_depth == 1 and curly_depth == 0: start = i curly_depth += 1 elif c == close_curly: curly_depth -= 1 if square_depth == 1 and curly_depth == 0: py_str = py_raw[start : i + 1].decode("utf8") try: yield srsly.json_loads(py_str) except Exception: print(py_str) raise start = -1 def iob_to_biluo(tags): out = [] tags = list(tags) while tags: out.extend(_consume_os(tags)) out.extend(_consume_ent(tags)) return out def _consume_os(tags): while tags and tags[0] == "O": yield tags.pop(0) def _consume_ent(tags): if not tags: return [] tag = tags.pop(0) target_in = "I" + tag[1:] target_last = "L" + tag[1:] length = 1 while tags and tags[0] in {target_in, target_last}: length += 1 tags.pop(0) label = tag[2:] if length == 1: if len(label) == 0: raise ValueError(Errors.E177.format(tag=tag)) return ["U-" + label] else: start = "B-" + label end = "L-" + label middle = ["I-%s" % label for _ in range(1, length - 1)] return [start] + middle + [end] cdef class GoldParse: """Collection for training annotations. DOCS: https://spacy.io/api/goldparse """ @classmethod def from_annot_tuples(cls, doc, annot_tuples, make_projective=False): _, words, tags, heads, deps, entities, cats = annot_tuples return cls(doc, words=words, tags=tags, heads=heads, deps=deps, entities=entities, cats=cats, make_projective=make_projective) def __init__(self, doc, annot_tuples=None, words=None, tags=None, morphology=None, heads=None, deps=None, entities=None, make_projective=False, cats=None, links=None, **_): """Create a GoldParse. doc (Doc): The document the annotations refer to. words (iterable): A sequence of unicode word strings. tags (iterable): A sequence of strings, representing tag annotations. heads (iterable): A sequence of integers, representing syntactic head offsets. deps (iterable): A sequence of strings, representing the syntactic relation types. entities (iterable): A sequence of named entity annotations, either as BILUO tag strings, or as `(start_char, end_char, label)` tuples, representing the entity positions. cats (dict): Labels for text classification. Each key in the dictionary may be a string or an int, or a `(start_char, end_char, label)` tuple, indicating that the label is applied to only part of the document (usually a sentence). Unlike entity annotations, label annotations can overlap, i.e. a single word can be covered by multiple labelled spans. The TextCategorizer component expects true examples of a label to have the value 1.0, and negative examples of a label to have the value 0.0. Labels not in the dictionary are treated as missing - the gradient for those labels will be zero. links (dict): A dict with `(start_char, end_char)` keys, and the values being dicts with kb_id:value entries, representing the external IDs in a knowledge base (KB) mapped to either 1.0 or 0.0, indicating positive and negative examples respectively. RETURNS (GoldParse): The newly constructed object. """ if words is None: words = [token.text for token in doc] if tags is None: tags = [None for _ in words] if heads is None: heads = [None for _ in words] if deps is None: deps = [None for _ in words] if morphology is None: morphology = [None for _ in words] if entities is None: entities = ["-" for _ in doc] elif len(entities) == 0: entities = ["O" for _ in doc] else: # Translate the None values to '-', to make processing easier. # See Issue #2603 entities = [(ent if ent is not None else "-") for ent in entities] if not isinstance(entities[0], basestring): # Assume we have entities specified by character offset. entities = biluo_tags_from_offsets(doc, entities) self.mem = Pool() self.loss = 0 self.length = len(doc) # These are filled by the tagger/parser/entity recogniser self.c.tags = self.mem.alloc(len(doc), sizeof(int)) self.c.heads = self.mem.alloc(len(doc), sizeof(int)) self.c.labels = self.mem.alloc(len(doc), sizeof(attr_t)) self.c.has_dep = self.mem.alloc(len(doc), sizeof(int)) self.c.sent_start = self.mem.alloc(len(doc), sizeof(int)) self.c.ner = self.mem.alloc(len(doc), sizeof(Transition)) self.cats = {} if cats is None else dict(cats) self.links = links self.words = [None] * len(doc) self.tags = [None] * len(doc) self.heads = [None] * len(doc) self.labels = [None] * len(doc) self.ner = [None] * len(doc) self.morphology = [None] * len(doc) # This needs to be done before we align the words if make_projective and heads is not None and deps is not None: heads, deps = nonproj.projectivize(heads, deps) # Do many-to-one alignment for misaligned tokens. # If we over-segment, we'll have one gold word that covers a sequence # of predicted words # If we under-segment, we'll have one predicted word that covers a # sequence of gold words. # If we "mis-segment", we'll have a sequence of predicted words covering # a sequence of gold words. That's many-to-many -- we don't do that. cost, i2j, j2i, i2j_multi, j2i_multi = align([t.orth_ for t in doc], words) self.cand_to_gold = [(j if j >= 0 else None) for j in i2j] self.gold_to_cand = [(i if i >= 0 else None) for i in j2i] annot_tuples = (range(len(words)), words, tags, heads, deps, entities) self.orig_annot = list(zip(*annot_tuples)) for i, gold_i in enumerate(self.cand_to_gold): if doc[i].text.isspace(): self.words[i] = doc[i].text self.tags[i] = "_SP" self.heads[i] = None self.labels[i] = None self.ner[i] = None self.morphology[i] = set() if gold_i is None: if i in i2j_multi: self.words[i] = words[i2j_multi[i]] self.tags[i] = tags[i2j_multi[i]] self.morphology[i] = morphology[i2j_multi[i]] is_last = i2j_multi[i] != i2j_multi.get(i+1) is_first = i2j_multi[i] != i2j_multi.get(i-1) # Set next word in multi-token span as head, until last if not is_last: self.heads[i] = i+1 self.labels[i] = "subtok" else: self.heads[i] = self.gold_to_cand[heads[i2j_multi[i]]] self.labels[i] = deps[i2j_multi[i]] # Now set NER...This is annoying because if we've split # got an entity word split into two, we need to adjust the # BILUO tags. We can't have BB or LL etc. # Case 1: O -- easy. ner_tag = entities[i2j_multi[i]] if ner_tag == "O": self.ner[i] = "O" # Case 2: U. This has to become a B I* L sequence. elif ner_tag.startswith("U-"): if is_first: self.ner[i] = ner_tag.replace("U-", "B-", 1) elif is_last: self.ner[i] = ner_tag.replace("U-", "L-", 1) else: self.ner[i] = ner_tag.replace("U-", "I-", 1) # Case 3: L. If not last, change to I. elif ner_tag.startswith("L-"): if is_last: self.ner[i] = ner_tag else: self.ner[i] = ner_tag.replace("L-", "I-", 1) # Case 4: I. Stays correct elif ner_tag.startswith("I-"): self.ner[i] = ner_tag else: self.words[i] = words[gold_i] self.tags[i] = tags[gold_i] self.morphology[i] = morphology[gold_i] if heads[gold_i] is None: self.heads[i] = None else: self.heads[i] = self.gold_to_cand[heads[gold_i]] self.labels[i] = deps[gold_i] self.ner[i] = entities[gold_i] # Prevent whitespace that isn't within entities from being tagged as # an entity. for i in range(len(self.ner)): if self.tags[i] == "_SP": prev_ner = self.ner[i-1] if i >= 1 else None next_ner = self.ner[i+1] if (i+1) < len(self.ner) else None if prev_ner == "O" or next_ner == "O": self.ner[i] = "O" cycle = nonproj.contains_cycle(self.heads) if cycle is not None: raise ValueError(Errors.E069.format(cycle=cycle, cycle_tokens=" ".join(["'{}'".format(self.words[tok_id]) for tok_id in cycle]), doc_tokens=" ".join(words[:50]))) def __len__(self): """Get the number of gold-standard tokens. RETURNS (int): The number of gold-standard tokens. """ return self.length @property def is_projective(self): """Whether the provided syntactic annotations form a projective dependency tree. """ return not nonproj.is_nonproj_tree(self.heads) property sent_starts: def __get__(self): return [self.c.sent_start[i] for i in range(self.length)] def __set__(self, sent_starts): for gold_i, is_sent_start in enumerate(sent_starts): i = self.gold_to_cand[gold_i] if i is not None: if is_sent_start in (1, True): self.c.sent_start[i] = 1 elif is_sent_start in (-1, False): self.c.sent_start[i] = -1 else: self.c.sent_start[i] = 0 def docs_to_json(docs, id=0): """Convert a list of Doc objects into the JSON-serializable format used by the spacy train command. docs (iterable / Doc): The Doc object(s) to convert. id (int): Id for the JSON. RETURNS (dict): The data in spaCy's JSON format - each input doc will be treated as a paragraph in the output doc """ if isinstance(docs, Doc): docs = [docs] json_doc = {"id": id, "paragraphs": []} for i, doc in enumerate(docs): json_para = {'raw': doc.text, "sentences": [], "cats": []} for cat, val in doc.cats.items(): json_cat = {"label": cat, "value": val} json_para["cats"].append(json_cat) ent_offsets = [(e.start_char, e.end_char, e.label_) for e in doc.ents] biluo_tags = biluo_tags_from_offsets(doc, ent_offsets) for j, sent in enumerate(doc.sents): json_sent = {"tokens": [], "brackets": []} for token in sent: json_token = {"id": token.i, "orth": token.text} if doc.is_tagged: json_token["tag"] = token.tag_ if doc.is_parsed: json_token["head"] = token.head.i-token.i json_token["dep"] = token.dep_ json_token["ner"] = biluo_tags[token.i] json_sent["tokens"].append(json_token) json_para["sentences"].append(json_sent) json_doc["paragraphs"].append(json_para) return json_doc def biluo_tags_from_offsets(doc, entities, missing="O"): """Encode labelled spans into per-token tags, using the Begin/In/Last/Unit/Out scheme (BILUO). doc (Doc): The document that the entity offsets refer to. The output tags will refer to the token boundaries within the document. entities (iterable): A sequence of `(start, end, label)` triples. `start` and `end` should be character-offset integers denoting the slice into the original string. RETURNS (list): A list of unicode strings, describing the tags. Each tag string will be of the form either "", "O" or "{action}-{label}", where action is one of "B", "I", "L", "U". The string "-" is used where the entity offsets don't align with the tokenization in the `Doc` object. The training algorithm will view these as missing values. "O" denotes a non-entity token. "B" denotes the beginning of a multi-token entity, "I" the inside of an entity of three or more tokens, and "L" the end of an entity of two or more tokens. "U" denotes a single-token entity. EXAMPLE: >>> text = 'I like London.' >>> entities = [(len('I like '), len('I like London'), 'LOC')] >>> doc = nlp.tokenizer(text) >>> tags = biluo_tags_from_offsets(doc, entities) >>> assert tags == ["O", "O", 'U-LOC', "O"] """ # Ensure no overlapping entity labels exist tokens_in_ents = {} starts = {token.idx: token.i for token in doc} ends = {token.idx + len(token): token.i for token in doc} biluo = ["-" for _ in doc] # Handle entity cases for start_char, end_char, label in entities: for token_index in range(start_char, end_char): if token_index in tokens_in_ents.keys(): raise ValueError(Errors.E103.format( span1=(tokens_in_ents[token_index][0], tokens_in_ents[token_index][1], tokens_in_ents[token_index][2]), span2=(start_char, end_char, label))) tokens_in_ents[token_index] = (start_char, end_char, label) start_token = starts.get(start_char) end_token = ends.get(end_char) # Only interested if the tokenization is correct if start_token is not None and end_token is not None: if start_token == end_token: biluo[start_token] = "U-%s" % label else: biluo[start_token] = "B-%s" % label for i in range(start_token+1, end_token): biluo[i] = "I-%s" % label biluo[end_token] = "L-%s" % label # Now distinguish the O cases from ones where we miss the tokenization entity_chars = set() for start_char, end_char, label in entities: for i in range(start_char, end_char): entity_chars.add(i) for token in doc: for i in range(token.idx, token.idx + len(token)): if i in entity_chars: break else: biluo[token.i] = missing return biluo def spans_from_biluo_tags(doc, tags): """Encode per-token tags following the BILUO scheme into Span object, e.g. to overwrite the doc.ents. doc (Doc): The document that the BILUO tags refer to. entities (iterable): A sequence of BILUO tags with each tag describing one token. Each tags string will be of the form of either "", "O" or "{action}-{label}", where action is one of "B", "I", "L", "U". RETURNS (list): A sequence of Span objects. """ token_offsets = tags_to_entities(tags) spans = [] for label, start_idx, end_idx in token_offsets: span = Span(doc, start_idx, end_idx + 1, label=label) spans.append(span) return spans def offsets_from_biluo_tags(doc, tags): """Encode per-token tags following the BILUO scheme into entity offsets. doc (Doc): The document that the BILUO tags refer to. entities (iterable): A sequence of BILUO tags with each tag describing one token. Each tags string will be of the form of either "", "O" or "{action}-{label}", where action is one of "B", "I", "L", "U". RETURNS (list): A sequence of `(start, end, label)` triples. `start` and `end` will be character-offset integers denoting the slice into the original string. """ spans = spans_from_biluo_tags(doc, tags) return [(span.start_char, span.end_char, span.label_) for span in spans] def is_punct_label(label): return label == "P" or label.lower() == "punct"