spaCy/examples/train_ner_standalone.py

236 lines
7.5 KiB
Python

'''Example of training a named entity recognition system from scratch using spaCy
This example is written to be self-contained and reasonably transparent.
To achieve that, it duplicates some of spaCy's internal functionality.
Specifically, in this example, we don't use spaCy's built-in Language class to
wire together the Vocab, Tokenizer and EntityRecognizer. Instead, we write
our own simle Pipeline class, so that it's easier to see how the pieces
interact.
Input data:
https://www.lt.informatik.tu-darmstadt.de/fileadmin/user_upload/Group_LangTech/data/GermEval2014_complete_data.zip
Developed for: spaCy 1.7.1
Last tested for: spaCy 1.7.1
'''
from __future__ import unicode_literals, print_function
import plac
from pathlib import Path
import random
import json
import spacy.orth as orth_funcs
from spacy.vocab import Vocab
from spacy.pipeline import BeamEntityRecognizer
from spacy.pipeline import EntityRecognizer
from spacy.tokenizer import Tokenizer
from spacy.tokens import Doc
from spacy.attrs import *
from spacy.gold import GoldParse
from spacy.gold import _iob_to_biluo as iob_to_biluo
from spacy.scorer import Scorer
try:
unicode
except NameError:
unicode = str
def init_vocab():
return Vocab(
lex_attr_getters={
LOWER: lambda string: string.lower(),
SHAPE: orth_funcs.word_shape,
PREFIX: lambda string: string[0],
SUFFIX: lambda string: string[-3:],
CLUSTER: lambda string: 0,
IS_ALPHA: orth_funcs.is_alpha,
IS_ASCII: orth_funcs.is_ascii,
IS_DIGIT: lambda string: string.isdigit(),
IS_LOWER: orth_funcs.is_lower,
IS_PUNCT: orth_funcs.is_punct,
IS_SPACE: lambda string: string.isspace(),
IS_TITLE: orth_funcs.is_title,
IS_UPPER: orth_funcs.is_upper,
IS_STOP: lambda string: False,
IS_OOV: lambda string: True
})
def save_vocab(vocab, path):
path = Path(path)
if not path.exists():
path.mkdir()
elif not path.is_dir():
raise IOError("Can't save vocab to %s\nNot a directory" % path)
with (path / 'strings.json').open('w') as file_:
vocab.strings.dump(file_)
vocab.dump((path / 'lexemes.bin').as_posix())
def load_vocab(path):
path = Path(path)
if not path.exists():
raise IOError("Cannot load vocab from %s\nDoes not exist" % path)
if not path.is_dir():
raise IOError("Cannot load vocab from %s\nNot a directory" % path)
return Vocab.load(path)
def init_ner_model(vocab, features=None):
if features is None:
features = tuple(EntityRecognizer.feature_templates)
return BeamEntityRecognizer(vocab, features=features)
def save_ner_model(model, path):
path = Path(path)
if not path.exists():
path.mkdir()
if not path.is_dir():
raise IOError("Can't save model to %s\nNot a directory" % path)
model.model.dump((path / 'model').as_posix())
with (path / 'config.json').open('w') as file_:
data = json.dumps(model.cfg)
if not isinstance(data, unicode):
data = data.decode('utf8')
file_.write(data)
def load_ner_model(vocab, path):
return BeamEntityRecognizer.load(path, vocab)
class Pipeline(object):
@classmethod
def load(cls, path):
path = Path(path)
if not path.exists():
raise IOError("Cannot load pipeline from %s\nDoes not exist" % path)
if not path.is_dir():
raise IOError("Cannot load pipeline from %s\nNot a directory" % path)
vocab = load_vocab(path / 'vocab')
tokenizer = Tokenizer(vocab, {}, None, None, None)
ner_model = load_ner_model(vocab, path / 'ner')
return cls(vocab, tokenizer, ner_model)
def __init__(self, vocab=None, tokenizer=None, ner_model=None):
if vocab is None:
self.vocab = init_vocab()
if tokenizer is None:
tokenizer = Tokenizer(vocab, {}, None, None, None)
if ner_model is None:
self.entity = init_ner_model(self.vocab)
self.pipeline = [self.entity]
def __call__(self, input_):
doc = self.make_doc(input_)
for process in self.pipeline:
process(doc)
return doc
def make_doc(self, input_):
if isinstance(input_, bytes):
input_ = input_.decode('utf8')
if isinstance(input_, unicode):
return self.tokenizer(input_)
else:
return Doc(self.vocab, words=input_)
def make_gold(self, input_, annotations):
doc = self.make_doc(input_)
gold = GoldParse(doc, entities=annotations)
return gold
def update(self, input_, annot):
doc = self.make_doc(input_)
gold = self.make_gold(input_, annot)
for ner in gold.ner:
if ner not in (None, '-', 'O'):
action, label = ner.split('-', 1)
self.entity.add_label(label)
return self.entity.update(doc, gold)
def evaluate(self, examples):
scorer = Scorer()
for input_, annot in examples:
gold = self.make_gold(input_, annot)
doc = self(input_)
scorer.score(doc, gold)
return scorer.scores
def average_weights(self):
self.entity.model.end_training()
def save(self, path):
path = Path(path)
if not path.exists():
path.mkdir()
elif not path.is_dir():
raise IOError("Can't save pipeline to %s\nNot a directory" % path)
save_vocab(self.vocab, path / 'vocab')
save_ner_model(self.entity, path / 'ner')
def train(nlp, train_examples, dev_examples, nr_epoch=5):
next_epoch = train_examples
print("Iter", "Loss", "P", "R", "F")
for i in range(nr_epoch):
this_epoch = next_epoch
next_epoch = []
loss = 0
for input_, annot in this_epoch:
loss += nlp.update(input_, annot)
if (i+1) < nr_epoch:
next_epoch.append((input_, annot))
random.shuffle(next_epoch)
scores = nlp.evaluate(dev_examples)
precision = '%.2f' % scores['ents_p']
recall = '%.2f' % scores['ents_r']
f_measure = '%.2f' % scores['ents_f']
print(i, int(loss), precision, recall, f_measure)
nlp.average_weights()
scores = nlp.evaluate(dev_examples)
print("After averaging")
print(scores['ents_p'], scores['ents_r'], scores['ents_f'])
def read_examples(path):
path = Path(path)
with path.open() as file_:
sents = file_.read().strip().split('\n\n')
for sent in sents:
if not sent.strip():
continue
tokens = sent.split('\n')
while tokens and tokens[0].startswith('#'):
tokens.pop(0)
words = []
iob = []
for token in tokens:
if token.strip():
pieces = token.split()
words.append(pieces[1])
iob.append(pieces[2])
yield words, iob_to_biluo(iob)
@plac.annotations(
model_dir=("Path to save the model", "positional", None, Path),
train_loc=("Path to your training data", "positional", None, Path),
dev_loc=("Path to your development data", "positional", None, Path),
)
def main(model_dir, train_loc, dev_loc, nr_epoch=10):
train_examples = read_examples(train_loc)
dev_examples = read_examples(dev_loc)
nlp = Pipeline()
train(nlp, train_examples, list(dev_examples), nr_epoch)
nlp.save(model_dir)
if __name__ == '__main__':
plac.call(main)