Update textcat example

This commit is contained in:
ines 2017-10-27 00:32:19 +02:00
parent 4eb5bd02e7
commit b61866a2e4

View File

@ -1,58 +1,119 @@
'''Train a multi-label convolutional neural network text classifier,
using the spacy.pipeline.TextCategorizer component. The model is then added
to spacy.pipeline, and predictions are available at `doc.cats`.
'''
from __future__ import unicode_literals
#!/usr/bin/env python
# coding: utf8
"""Train a multi-label convolutional neural network text classifier on the
IMDB dataset, using the TextCategorizer component. The dataset will be loaded
automatically via Thinc's built-in dataset loader. The model is then added to
spacy.pipeline, and predictions are available via `doc.cats`.
For more details, see the documentation:
* Training: https://alpha.spacy.io/usage/training
* Text classification: https://alpha.spacy.io/usage/text-classification
Developed for: spaCy 2.0.0a18
Last updated for: spaCy 2.0.0a18
"""
from __future__ import unicode_literals, print_function
import plac
import random
import tqdm
from thinc.neural.optimizers import Adam
from thinc.neural.ops import NumpyOps
from pathlib import Path
import thinc.extra.datasets
import spacy.lang.en
import spacy
from spacy.gold import GoldParse, minibatch
from spacy.util import compounding
from spacy.pipeline import TextCategorizer
# TODO: Remove this once we're not supporting models trained with thinc <6.9.0
import thinc.neural._classes.layernorm
thinc.neural._classes.layernorm.set_compat_six_eight(False)
@plac.annotations(
model=("Model name. Defaults to blank 'en' model.", "option", "m", str),
output_dir=("Optional output directory", "option", "o", Path),
n_iter=("Number of training iterations", "option", "n", int))
def main(model=None, output_dir=None, n_iter=20):
if model is not None:
nlp = spacy.load(model) # load existing spaCy model
print("Loaded model '%s'" % model)
else:
nlp = spacy.blank('en') # create blank Language class
print("Created blank 'en' model")
def train_textcat(tokenizer, textcat,
train_texts, train_cats, dev_texts, dev_cats,
n_iter=20):
'''
Train the TextCategorizer without associated pipeline.
'''
textcat.begin_training()
optimizer = Adam(NumpyOps(), 0.001)
train_docs = [tokenizer(text) for text in train_texts]
# add the text classifier to the pipeline if it doesn't exist
# nlp.create_pipe works for built-ins that are registered with spaCy
if 'textcat' not in nlp.pipe_names:
# textcat = nlp.create_pipe('textcat')
textcat = TextCategorizer(nlp.vocab, labels=['POSITIVE'])
nlp.add_pipe(textcat, first=True)
# otherwise, get it, so we can add labels to it
else:
textcat = nlp.get_pipe('textcat')
# add label to text classifier
# textcat.add_label('POSITIVE')
# load the IMBD dataset
print("Loading IMDB data...")
(train_texts, train_cats), (dev_texts, dev_cats) = load_data(limit=2000)
train_docs = [nlp.tokenizer(text) for text in train_texts]
train_gold = [GoldParse(doc, cats=cats) for doc, cats in
zip(train_docs, train_cats)]
train_data = list(zip(train_docs, train_gold))
batch_sizes = compounding(4., 128., 1.001)
for i in range(n_iter):
losses = {}
# Progress bar and minibatching
batches = minibatch(tqdm.tqdm(train_data, leave=False), size=batch_sizes)
for batch in batches:
docs, golds = zip(*batch)
textcat.update(docs, golds, sgd=optimizer, drop=0.2,
losses=losses)
with textcat.model.use_params(optimizer.averages):
scores = evaluate(tokenizer, textcat, dev_texts, dev_cats)
yield losses['textcat'], scores
# get names of other pipes to disable them during training
other_pipes = [pipe for pipe in nlp.pipe_names if pipe != 'textcat']
with nlp.disable_pipes(*other_pipes): # only train textcat
optimizer = nlp.begin_training(lambda: [])
print("Training the model...")
print('{:^5}\t{:^5}\t{:^5}\t{:^5}'.format('LOSS', 'P', 'R', 'F'))
for i in range(n_iter):
losses = {}
# batch up the examples using spaCy's minibatch
batches = minibatch(train_data, size=compounding(4., 128., 1.001))
for batch in batches:
docs, golds = zip(*batch)
nlp.update(docs, golds, sgd=optimizer, drop=0.2, losses=losses)
with textcat.model.use_params(optimizer.averages):
# evaluate on the dev data split off in load_data()
scores = evaluate(nlp.tokenizer, textcat, dev_texts, dev_cats)
print('{0:.3f}\t{0:.3f}\t{0:.3f}\t{0:.3f}' # print a simple table
.format(losses['textcat'], scores['textcat_p'],
scores['textcat_r'], scores['textcat_f']))
# test the trained model
test_text = "This movie sucked"
doc = nlp(test_text)
print(test_text, doc.cats)
if output_dir is not None:
output_dir = Path(output_dir)
if not output_dir.exists():
output_dir.mkdir()
nlp.to_disk(output_dir)
print("Saved model to", output_dir)
# test the saved model
print("Loading from", output_dir)
nlp2 = spacy.load(output_dir)
doc2 = nlp2(test_text)
print(test_text, doc2.cats)
def load_data(limit=0, split=0.8):
"""Load data from the IMDB dataset."""
# Partition off part of the train data for evaluation
train_data, _ = thinc.extra.datasets.imdb()
random.shuffle(train_data)
train_data = train_data[-limit:]
texts, labels = zip(*train_data)
cats = [{'POSITIVE': bool(y)} for y in labels]
split = int(len(train_data) * split)
return (texts[:split], cats[:split]), (texts[split:], cats[split:])
def evaluate(tokenizer, textcat, texts, cats):
docs = (tokenizer(text) for text in texts)
tp = 1e-8 # True positives
fp = 1e-8 # False positives
fn = 1e-8 # False negatives
tn = 1e-8 # True negatives
tp = 1e-8 # True positives
fp = 1e-8 # False positives
fn = 1e-8 # False negatives
tn = 1e-8 # True negatives
for i, doc in enumerate(textcat.pipe(docs)):
gold = cats[i]
for label, score in doc.cats.items():
@ -66,55 +127,10 @@ def evaluate(tokenizer, textcat, texts, cats):
tn += 1
elif score < 0.5 and gold[label] >= 0.5:
fn += 1
precis = tp / (tp + fp)
precision = tp / (tp + fp)
recall = tp / (tp + fn)
fscore = 2 * (precis * recall) / (precis + recall)
return {'textcat_p': precis, 'textcat_r': recall, 'textcat_f': fscore}
def load_data(limit=0):
# Partition off part of the train data --- avoid running experiments
# against test.
train_data, _ = thinc.extra.datasets.imdb()
random.shuffle(train_data)
train_data = train_data[-limit:]
texts, labels = zip(*train_data)
cats = [{'POSITIVE': bool(y)} for y in labels]
split = int(len(train_data) * 0.8)
train_texts = texts[:split]
train_cats = cats[:split]
dev_texts = texts[split:]
dev_cats = cats[split:]
return (train_texts, train_cats), (dev_texts, dev_cats)
def main(model_loc=None):
nlp = spacy.lang.en.English()
tokenizer = nlp.tokenizer
textcat = TextCategorizer(tokenizer.vocab, labels=['POSITIVE'])
print("Load IMDB data")
(train_texts, train_cats), (dev_texts, dev_cats) = load_data(limit=2000)
print("Itn.\tLoss\tP\tR\tF")
progress = '{i:d} {loss:.3f} {textcat_p:.3f} {textcat_r:.3f} {textcat_f:.3f}'
for i, (loss, scores) in enumerate(train_textcat(tokenizer, textcat,
train_texts, train_cats,
dev_texts, dev_cats, n_iter=20)):
print(progress.format(i=i, loss=loss, **scores))
# How to save, load and use
nlp.pipeline.append(textcat)
if model_loc is not None:
nlp.to_disk(model_loc)
nlp = spacy.load(model_loc)
doc = nlp(u'This movie sucked!')
print(doc.cats)
f_score = 2 * (precision * recall) / (precision + recall)
return {'textcat_p': precision, 'textcat_r': recall, 'textcat_f': f_score}
if __name__ == '__main__':