spaCy/spacy/cli/model.py
2017-03-26 20:56:05 +02:00

130 lines
4.4 KiB
Python

# coding: utf8
from __future__ import unicode_literals
import gzip
import math
from ast import literal_eval
from pathlib import Path
from preshed.counter import PreshCounter
from ..vocab import write_binary_vectors
from .. import util
def model(lang, model_dir, freqs_data, clusters_data, vectors_data):
model_path = Path(model_dir)
freqs_path = Path(freqs_data)
clusters_path = Path(clusters_data) if clusters_data else None
vectors_path = Path(vectors_data) if vectors_data else None
check_dirs(freqs_path, clusters_path, vectors_path)
vocab = util.get_lang_class(lang).Defaults.create_vocab()
probs, oov_prob = read_probs(freqs_path)
clusters = read_clusters(clusters_path) if clusters_path else {}
populate_vocab(vocab, clusters, probs, oov_prob)
create_model(model_path, vectors_path, vocab, oov_prob)
def create_model(model_path, vectors_path, vocab, oov_prob):
vocab_path = model_path / 'vocab'
lexemes_path = vocab_path / 'lexemes.bin'
strings_path = vocab_path / 'strings.json'
oov_path = vocab_path / 'oov_prob'
if not model_path.exists():
model_path.mkdir()
if not vocab_path.exists():
vocab_path.mkdir()
vocab.dump(lexemes_path.as_posix())
with strings_path.open('w') as f:
vocab.strings.dump(f)
with oov_path.open('w') as f:
f.write('%f' % oov_prob)
if vectors_path:
vectors_dest = model_path / 'vec.bin'
write_binary_vectors(vectors_path.as_posix(), vectors_dest.as_posix())
def read_probs(freqs_path, max_length=100, min_doc_freq=5, min_freq=200):
counts = PreshCounter()
total = 0
freqs_file = check_unzip(freqs_path)
for i, line in enumerate(freqs_file):
freq, doc_freq, key = line.rstrip().split('\t', 2)
freq = int(freq)
counts.inc(i+1, freq)
total += freq
counts.smooth()
log_total = math.log(total)
freqs_file = check_unzip(freqs_path)
probs = {}
for line in freqs_file:
freq, doc_freq, key = line.rstrip().split('\t', 2)
doc_freq = int(doc_freq)
freq = int(freq)
if doc_freq >= min_doc_freq and freq >= min_freq and len(key) < max_length:
word = literal_eval(key)
smooth_count = counts.smoother(int(freq))
probs[word] = math.log(smooth_count) - log_total
oov_prob = math.log(counts.smoother(0)) - log_total
return probs, oov_prob
def read_clusters(clusters_path):
clusters = {}
with clusters_path.open() as f:
for line in f:
try:
cluster, word, freq = line.split()
except ValueError:
continue
# If the clusterer has only seen the word a few times, its
# cluster is unreliable.
if int(freq) >= 3:
clusters[word] = cluster
else:
clusters[word] = '0'
# Expand clusters with re-casing
for word, cluster in list(clusters.items()):
if word.lower() not in clusters:
clusters[word.lower()] = cluster
if word.title() not in clusters:
clusters[word.title()] = cluster
if word.upper() not in clusters:
clusters[word.upper()] = cluster
return clusters
def populate_vocab(vocab, clusters, probs, oov_probs):
# Ensure probs has entries for all words seen during clustering.
for word in clusters:
if word not in probs:
probs[word] = oov_prob
for word, prob in reversed(sorted(list(probs.items()), key=lambda item: item[1])):
lexeme = vocab[word]
lexeme.prob = prob
lexeme.is_oov = False
# Decode as a little-endian string, so that we can do & 15 to get
# the first 4 bits. See _parse_features.pyx
if word in clusters:
lexeme.cluster = int(clusters[word][::-1], 2)
else:
lexeme.cluster = 0
def check_unzip(file_path):
file_path_str = file_path.as_posix()
if file_path_str.endswith('gz'):
return gzip.open(file_path_str)
else:
return file_path.open()
def check_dirs(freqs_data, clusters_data, vectors_data):
if not freqs_data.is_file():
util.sys_exit(freqs_data.as_posix(), title="No frequencies file found")
if clusters_data and not clusters_data.is_file():
util.sys_exit(clusters_data.as_posix(), title="No Brown clusters file found")
if vectors_data and not vectors_data.is_file():
util.sys_exit(vectors_data.as_posix(), title="No word vectors file found")