spaCy/examples/deep_learning_keras.py
2016-10-20 21:32:26 +02:00

183 lines
6.5 KiB
Python

import plac
import collections
import random
import pathlib
import cytoolz
import numpy
from keras.models import Sequential, model_from_json
from keras.layers import LSTM, Dense, Embedding, Dropout, Bidirectional
from keras.layers import TimeDistributed
from keras.optimizers import Adam
import cPickle as pickle
import spacy
class SentimentAnalyser(object):
@classmethod
def load(cls, path, nlp):
with (path / 'config.json').open() as file_:
model = model_from_json(file_.read())
with (path / 'model').open('rb') as file_:
lstm_weights = pickle.load(file_)
embeddings = get_embeddings(nlp.vocab)
model.set_weights([embeddings] + lstm_weights)
return cls(model)
def __init__(self, model):
self._model = model
def __call__(self, doc):
X = get_features([doc], self.max_length)
y = self._model.predict(X)
self.set_sentiment(doc, y)
def pipe(self, docs, batch_size=1000, n_threads=2):
for minibatch in cytoolz.partition_all(batch_size, docs):
Xs = get_features(minibatch, self.max_length)
ys = self._model.predict(Xs)
for i, doc in enumerate(minibatch):
doc.user_data['sentiment'] = ys[i]
def set_sentiment(self, doc, y):
doc.sentiment = float(y[0])
# Sentiment has a native slot for a single float.
# For arbitrary data storage, there's:
# doc.user_data['my_data'] = y
def get_features(docs, max_length):
docs = list(docs)
Xs = numpy.zeros((len(docs), max_length), dtype='int32')
for i, doc in enumerate(docs):
j = 0
for token in doc:
if token.has_vector and not token.is_punct and not token.is_space:
Xs[i, j] = token.rank + 1
j += 1
if j >= max_length:
break
return Xs
def train(train_texts, train_labels, dev_texts, dev_labels,
lstm_shape, lstm_settings, lstm_optimizer, batch_size=100, nb_epoch=5):
nlp = spacy.load('en', parser=False, tagger=False, entity=False)
embeddings = get_embeddings(nlp.vocab)
model = compile_lstm(embeddings, lstm_shape, lstm_settings)
train_X = get_features(nlp.pipe(train_texts), lstm_shape['max_length'])
dev_X = get_features(nlp.pipe(dev_texts), lstm_shape['max_length'])
model.fit(train_X, train_labels, validation_data=(dev_X, dev_labels),
nb_epoch=nb_epoch, batch_size=batch_size)
return model
def compile_lstm(embeddings, shape, settings):
model = Sequential()
model.add(
Embedding(
embeddings.shape[0],
embeddings.shape[1],
input_length=shape['max_length'],
trainable=False,
weights=[embeddings],
mask_zero=True
)
)
model.add(TimeDistributed(Dense(shape['nr_hidden'] * 2)))
model.add(Dropout(settings['dropout']))
model.add(Bidirectional(LSTM(shape['nr_hidden'])))
model.add(Dropout(settings['dropout']))
model.add(Dense(shape['nr_class'], activation='sigmoid'))
model.compile(optimizer=Adam(lr=settings['lr']), loss='binary_crossentropy',
metrics=['accuracy'])
return model
def get_embeddings(vocab):
max_rank = max(lex.rank+1 for lex in vocab if lex.has_vector)
vectors = numpy.ndarray((max_rank+1, vocab.vectors_length), dtype='float32')
for lex in vocab:
if lex.has_vector:
vectors[lex.rank + 1] = lex.vector
return vectors
def demonstrate_runtime(model_dir, texts):
'''Demonstrate runtime usage of the custom sentiment model with spaCy.
Here we return a dictionary mapping entities to the average sentiment of the
documents they occurred in.
'''
def create_pipeline(nlp):
'''
This could be a lambda, but named functions are easier to read in Python.
'''
return [nlp.tagger, nlp.entity, SentimentAnalyser.load(model_dir, nlp)]
nlp = spacy.load('en', create_pipeline=create_pipeline)
entity_sentiments = collections.Counter(float)
for doc in nlp.pipe(texts, batch_size=1000, n_threads=4):
for ent in doc.ents:
entity_sentiments[ent.text] += doc.sentiment
return entity_sentiments
def read_data(data_dir, limit=0):
examples = []
for subdir, label in (('pos', 1), ('neg', 0)):
for filename in (data_dir / subdir).iterdir():
with filename.open() as file_:
text = file_.read()
examples.append((text, label))
random.shuffle(examples)
if limit >= 1:
examples = examples[:limit]
return zip(*examples) # Unzips into two lists
@plac.annotations(
train_dir=("Location of training file or directory"),
dev_dir=("Location of development file or directory"),
model_dir=("Location of output model directory",),
is_runtime=("Demonstrate run-time usage", "flag", "r", bool),
nr_hidden=("Number of hidden units", "option", "H", int),
max_length=("Maximum sentence length", "option", "L", int),
dropout=("Dropout", "option", "d", float),
learn_rate=("Learn rate", "option", "e", float),
nb_epoch=("Number of training epochs", "option", "i", int),
batch_size=("Size of minibatches for training LSTM", "option", "b", int),
nr_examples=("Limit to N examples", "option", "n", int)
)
def main(model_dir, train_dir, dev_dir,
is_runtime=False,
nr_hidden=64, max_length=100, # Shape
dropout=0.5, learn_rate=0.001, # General NN config
nb_epoch=5, batch_size=100, nr_examples=-1): # Training params
model_dir = pathlib.Path(model_dir)
train_dir = pathlib.Path(train_dir)
dev_dir = pathlib.Path(dev_dir)
if is_runtime:
dev_texts, dev_labels = read_data(dev_dir)
demonstrate_runtime(model_dir, dev_texts)
else:
train_texts, train_labels = read_data(train_dir, limit=nr_examples)
dev_texts, dev_labels = read_data(dev_dir)
train_labels = numpy.asarray(train_labels, dtype='int32')
dev_labels = numpy.asarray(dev_labels, dtype='int32')
lstm = train(train_texts, train_labels, dev_texts, dev_labels,
{'nr_hidden': nr_hidden, 'max_length': max_length, 'nr_class': 1},
{'dropout': 0.5, 'lr': learn_rate},
{},
nb_epoch=nb_epoch, batch_size=batch_size)
weights = lstm.get_weights()
with (model_dir / 'model').open('wb') as file_:
pickle.dump(file_, weights[1:])
if __name__ == '__main__':
plac.call(main)