spaCy/spacy/syntax/nn_parser.pyx
2018-05-07 18:31:04 +02:00

465 lines
19 KiB
Cython

# cython: infer_types=True
# cython: cdivision=True
# cython: boundscheck=False
# coding: utf-8
from __future__ import unicode_literals, print_function
from collections import OrderedDict
import ujson
import json
import numpy
cimport cython.parallel
import cytoolz
import numpy.random
cimport numpy as np
from cpython.ref cimport PyObject, Py_XDECREF
from cpython.exc cimport PyErr_CheckSignals, PyErr_SetFromErrno
from libc.math cimport exp
from libcpp.vector cimport vector
from libc.string cimport memset, memcpy
from libc.stdlib cimport calloc, free
from cymem.cymem cimport Pool
from thinc.typedefs cimport weight_t, class_t, hash_t
from thinc.extra.search cimport Beam
from thinc.api import chain, clone
from thinc.v2v import Model, Maxout, Affine
from thinc.misc import LayerNorm
from thinc.neural.ops import CupyOps
from thinc.neural.util import get_array_module
from thinc.linalg cimport Vec, VecVec
from thinc cimport openblas
from ._parser_model cimport resize_activations, predict_states, arg_max_if_valid
from ._parser_model cimport WeightsC, ActivationsC, SizesC, cpu_log_loss
from ._parser_model cimport get_c_weights, get_c_sizes
from ._parser_model import ParserModel
from .._ml import zero_init, PrecomputableAffine, Tok2Vec, flatten
from .._ml import link_vectors_to_models, create_default_optimizer
from ..compat import json_dumps, copy_array
from ..tokens.doc cimport Doc
from ..gold cimport GoldParse
from ..errors import Errors, TempErrors
from .. import util
from .stateclass cimport StateClass
from ._state cimport StateC
from .transition_system cimport Transition
from . import nonproj
cdef class Parser:
"""
Base class of the DependencyParser and EntityRecognizer.
"""
@classmethod
def Model(cls, nr_class, **cfg):
depth = util.env_opt('parser_hidden_depth', cfg.get('hidden_depth', 1))
if depth != 1:
raise ValueError(TempErrors.T004.format(value=depth))
parser_maxout_pieces = util.env_opt('parser_maxout_pieces',
cfg.get('maxout_pieces', 2))
token_vector_width = util.env_opt('token_vector_width',
cfg.get('token_vector_width', 128))
hidden_width = util.env_opt('hidden_width', cfg.get('hidden_width', 128))
embed_size = util.env_opt('embed_size', cfg.get('embed_size', 5000))
pretrained_vectors = cfg.get('pretrained_vectors', None)
tok2vec = Tok2Vec(token_vector_width, embed_size,
pretrained_vectors=pretrained_vectors)
tok2vec = chain(tok2vec, flatten)
lower = PrecomputableAffine(hidden_width,
nF=cls.nr_feature, nI=token_vector_width,
nP=parser_maxout_pieces)
lower.nP = parser_maxout_pieces
with Model.use_device('cpu'):
upper = zero_init(Affine(nr_class, hidden_width, drop_factor=0.0))
cfg = {
'nr_class': nr_class,
'hidden_depth': depth,
'token_vector_width': token_vector_width,
'hidden_width': hidden_width,
'maxout_pieces': parser_maxout_pieces,
'pretrained_vectors': pretrained_vectors,
}
return ParserModel(tok2vec, lower, upper), cfg
def __init__(self, Vocab vocab, moves=True, model=True, **cfg):
"""Create a Parser.
vocab (Vocab): The vocabulary object. Must be shared with documents
to be processed. The value is set to the `.vocab` attribute.
moves (TransitionSystem): Defines how the parse-state is created,
updated and evaluated. The value is set to the .moves attribute
unless True (default), in which case a new instance is created with
`Parser.Moves()`.
model (object): Defines how the parse-state is created, updated and
evaluated. The value is set to the .model attribute. If set to True
(default), a new instance will be created with `Parser.Model()`
in parser.begin_training(), parser.from_disk() or parser.from_bytes().
**cfg: Arbitrary configuration parameters. Set to the `.cfg` attribute
"""
self.vocab = vocab
if moves is True:
self.moves = self.TransitionSystem(self.vocab.strings)
else:
self.moves = moves
if 'beam_width' not in cfg:
cfg['beam_width'] = util.env_opt('beam_width', 1)
if 'beam_density' not in cfg:
cfg['beam_density'] = util.env_opt('beam_density', 0.0)
cfg.setdefault('cnn_maxout_pieces', 3)
self.cfg = cfg
self.model = model
self._multitasks = []
def __reduce__(self):
return (Parser, (self.vocab, self.moves, self.model), None, None)
@property
def move_names(self):
names = []
for i in range(self.moves.n_moves):
name = self.moves.move_name(self.moves.c[i].move, self.moves.c[i].label)
names.append(name)
return names
nr_feature = 8
@property
def labels(self):
class_names = [self.moves.get_class_name(i) for i in range(self.moves.n_moves)]
return class_names
@property
def tok2vec(self):
'''Return the embedding and convolutional layer of the model.'''
return None if self.model in (None, True, False) else self.model.tok2vec
@property
def postprocesses(self):
# Available for subclasses, e.g. to deprojectivize
return []
def add_label(self, label):
resized = False
for action in self.moves.action_types:
added = self.moves.add_action(action, label)
if added:
resized = True
if self.model not in (True, False, None) and resized:
self.model.resize_output(self.moves.n_moves)
def add_multitask_objective(self, target):
# Defined in subclasses, to avoid circular import
raise NotImplementedError
def init_multitask_objectives(self, get_gold_tuples, pipeline, **cfg):
'''Setup models for secondary objectives, to benefit from multi-task
learning. This method is intended to be overridden by subclasses.
For instance, the dependency parser can benefit from sharing
an input representation with a label prediction model. These auxiliary
models are discarded after training.
'''
pass
def preprocess_gold(self, docs_golds):
for doc, gold in docs_golds:
yield doc, gold
def use_params(self, params):
# Can't decorate cdef class :(. Workaround.
with self.model.use_params(params):
yield
def __call__(self, Doc doc, beam_width=None, beam_density=None):
"""Apply the parser or entity recognizer, setting the annotations onto
the `Doc` object.
doc (Doc): The document to be processed.
"""
if beam_width is None:
beam_width = self.cfg.get('beam_width', 1)
if beam_density is None:
beam_density = self.cfg.get('beam_density', 0.0)
states = self.predict([doc])
self.set_annotations([doc], states, tensors=None)
return doc
def pipe(self, docs, int batch_size=256, int n_threads=2,
beam_width=None, beam_density=None):
"""Process a stream of documents.
stream: The sequence of documents to process.
batch_size (int): Number of documents to accumulate into a working set.
n_threads (int): The number of threads with which to work on the buffer
in parallel.
YIELDS (Doc): Documents, in order.
"""
if beam_width is None:
beam_width = self.cfg.get('beam_width', 1)
if beam_density is None:
beam_density = self.cfg.get('beam_density', 0.0)
cdef Doc doc
for batch in cytoolz.partition_all(batch_size, docs):
batch_in_order = list(batch)
by_length = sorted(batch_in_order, key=lambda doc: len(doc))
for subbatch in cytoolz.partition_all(8, by_length):
subbatch = list(subbatch)
parse_states = self.predict(subbatch,
beam_width=beam_width,
beam_density=beam_density)
self.set_annotations(subbatch, parse_states, tensors=None)
for doc in batch_in_order:
yield doc
def predict(self, docs, beam_width=1, beam_density=0.):
if isinstance(docs, Doc):
docs = [docs]
cdef vector[StateC*] states
cdef StateClass state
state_objs = self.moves.init_batch(docs)
for state in state_objs:
states.push_back(state.c)
# Prepare the stepwise model, and get the callback for finishing the batch
model = self.model(docs)
weights = get_c_weights(model)
sizes = get_c_sizes(model, states.size())
with nogil:
self._parseC(&states[0],
weights, sizes)
return state_objs
cdef void _parseC(self, StateC** states,
WeightsC weights, SizesC sizes) nogil:
cdef int i, j
cdef vector[StateC*] unfinished
cdef ActivationsC activations
memset(&activations, 0, sizeof(activations))
while sizes.states >= 1:
predict_states(&activations,
states, &weights, sizes)
# Validate actions, argmax, take action.
self.c_transition_batch(states,
activations.scores, sizes.classes, sizes.states)
for i in range(sizes.states):
if not states[i].is_final():
unfinished.push_back(states[i])
for i in range(unfinished.size()):
states[i] = unfinished[i]
sizes.states = unfinished.size()
unfinished.clear()
def set_annotations(self, docs, states, tensors=None):
cdef StateClass state
cdef Doc doc
for i, (state, doc) in enumerate(zip(states, docs)):
self.moves.finalize_state(state.c)
for j in range(doc.length):
doc.c[j] = state.c._sent[j]
self.moves.finalize_doc(doc)
for hook in self.postprocesses:
for doc in docs:
hook(doc)
def transition_batch(self, states, float[:, ::1] scores):
cdef StateClass state
cdef float* c_scores = &scores[0, 0]
cdef vector[StateC*] c_states
for state in states:
c_states.push_back(state.c)
self.c_transition_batch(&c_states[0], c_scores, scores.shape[1], scores.shape[0])
cdef void c_transition_batch(self, StateC** states, const float* scores,
int nr_class, int batch_size) nogil:
cdef int[500] is_valid # TODO: Unhack
cdef int i, guess
cdef Transition action
for i in range(batch_size):
self.moves.set_valid(is_valid, states[i])
guess = arg_max_if_valid(&scores[i*nr_class], is_valid, nr_class)
action = self.moves.c[guess]
action.do(states[i], action.label)
states[i].push_hist(guess)
def update(self, docs, golds, drop=0., sgd=None, losses=None):
if isinstance(docs, Doc) and isinstance(golds, GoldParse):
docs = [docs]
golds = [golds]
if len(docs) != len(golds):
raise ValueError(Errors.E077.format(value='update', n_docs=len(docs),
n_golds=len(golds)))
# Chop sequences into lengths of this many transitions, to make the
# batch uniform length.
cut_gold = numpy.random.choice(range(20, 100))
states, golds, max_steps = self._init_gold_batch(docs, golds, max_length=cut_gold)
states_golds = [(s, g) for (s, g) in zip(states, golds)
if not s.is_final() and g is not None]
# Prepare the stepwise model, and get the callback for finishing the batch
model, finish_update = self.model.begin_update(docs, drop=drop)
for _ in range(max_steps):
if not states_golds:
break
states, golds = zip(*states_golds)
scores, backprop = model.begin_update(states, drop=drop)
d_scores = self.get_batch_loss(states, golds, scores, losses)
backprop(d_scores, sgd=sgd)
# Follow the predicted action
self.transition_batch(states, scores)
states_golds = [eg for eg in states_golds if not eg[0].is_final()]
# Do the backprop
finish_update(golds, sgd=sgd)
return losses
def _init_gold_batch(self, whole_docs, whole_golds, min_length=5, max_length=500):
"""Make a square batch, of length equal to the shortest doc. A long
doc will get multiple states. Let's say we have a doc of length 2*N,
where N is the shortest doc. We'll make two states, one representing
long_doc[:N], and another representing long_doc[N:]."""
cdef:
StateClass state
Transition action
whole_states = self.moves.init_batch(whole_docs)
max_length = max(min_length, min(max_length, min([len(doc) for doc in whole_docs])))
max_moves = 0
states = []
golds = []
for doc, state, gold in zip(whole_docs, whole_states, whole_golds):
gold = self.moves.preprocess_gold(gold)
if gold is None:
continue
oracle_actions = self.moves.get_oracle_sequence(doc, gold)
start = 0
while start < len(doc):
state = state.copy()
n_moves = 0
while state.B(0) < start and not state.is_final():
action = self.moves.c[oracle_actions.pop(0)]
action.do(state.c, action.label)
state.c.push_hist(action.clas)
n_moves += 1
has_gold = self.moves.has_gold(gold, start=start,
end=start+max_length)
if not state.is_final() and has_gold:
states.append(state)
golds.append(gold)
max_moves = max(max_moves, n_moves)
start += min(max_length, len(doc)-start)
max_moves = max(max_moves, len(oracle_actions))
return states, golds, max_moves
def get_batch_loss(self, states, golds, float[:, ::1] scores, losses):
cdef StateClass state
cdef GoldParse gold
cdef Pool mem = Pool()
cdef int i
is_valid = <int*>mem.alloc(self.moves.n_moves, sizeof(int))
costs = <float*>mem.alloc(self.moves.n_moves, sizeof(float))
cdef np.ndarray d_scores = numpy.zeros((len(states), self.moves.n_moves),
dtype='f', order='C')
c_d_scores = <float*>d_scores.data
for i, (state, gold) in enumerate(zip(states, golds)):
memset(is_valid, 0, self.moves.n_moves * sizeof(int))
memset(costs, 0, self.moves.n_moves * sizeof(float))
self.moves.set_costs(is_valid, costs, state, gold)
cpu_log_loss(c_d_scores,
costs, is_valid, &scores[i, 0], d_scores.shape[1])
c_d_scores += d_scores.shape[1]
if losses is not None:
losses.setdefault(self.name, 0.)
losses[self.name] += (d_scores**2).sum()
return d_scores
def create_optimizer(self):
return create_default_optimizer(self.model.ops,
**self.cfg.get('optimizer', {}))
def begin_training(self, get_gold_tuples, pipeline=None, sgd=None, **cfg):
if 'model' in cfg:
self.model = cfg['model']
if not hasattr(get_gold_tuples, '__call__'):
gold_tuples = get_gold_tuples
get_gold_tuples = lambda: gold_tuples
cfg.setdefault('min_action_freq', 30)
actions = self.moves.get_actions(gold_parses=get_gold_tuples(),
min_freq=cfg.get('min_action_freq', 30))
self.moves.initialize_actions(actions)
cfg.setdefault('token_vector_width', 128)
if self.model is True:
self.model, cfg = self.Model(self.moves.n_moves, **cfg)
if sgd is None:
sgd = self.create_optimizer()
self.model.begin_training(
self.model.ops.allocate((5, cfg['token_vector_width'])))
if pipeline is not None:
self.init_multitask_objectives(get_gold_tuples, pipeline, sgd=sgd, **cfg)
link_vectors_to_models(self.vocab)
else:
if sgd is None:
sgd = self.create_optimizer()
self.model.begin_training(
self.model.ops.allocate((5, cfg['token_vector_width'])))
self.cfg.update(cfg)
return sgd
def to_disk(self, path, **exclude):
serializers = {
'model': lambda p: self.model.to_disk(p),
'vocab': lambda p: self.vocab.to_disk(p),
'moves': lambda p: self.moves.to_disk(p, strings=False),
'cfg': lambda p: p.open('w').write(json_dumps(self.cfg))
}
util.to_disk(path, serializers, exclude)
def from_disk(self, path, **exclude):
deserializers = {
'vocab': lambda p: self.vocab.from_disk(p),
'moves': lambda p: self.moves.from_disk(p, strings=False),
'cfg': lambda p: self.cfg.update(util.read_json(p)),
'model': lambda p: None
}
util.from_disk(path, deserializers, exclude)
if 'model' not in exclude:
path = util.ensure_path(path)
if self.model is True:
self.model, cfg = self.Model(**self.cfg)
else:
cfg = {}
with (path / 'tok2vec_model').open('rb') as file_:
bytes_data = file_.read()
self.model.from_bytes(bytes_data)
self.cfg.update(cfg)
return self
def to_bytes(self, **exclude):
serializers = OrderedDict((
('model', lambda: self.model.to_bytes()),
('vocab', lambda: self.vocab.to_bytes()),
('moves', lambda: self.moves.to_bytes(strings=False)),
('cfg', lambda: json.dumps(self.cfg, indent=2, sort_keys=True))
))
return util.to_bytes(serializers, exclude)
def from_bytes(self, bytes_data, **exclude):
deserializers = OrderedDict((
('vocab', lambda b: self.vocab.from_bytes(b)),
('moves', lambda b: self.moves.from_bytes(b, strings=False)),
('cfg', lambda b: self.cfg.update(json.loads(b))),
('model', lambda b: None)
))
msg = util.from_bytes(bytes_data, deserializers, exclude)
if 'model' not in exclude:
# TODO: Remove this once we don't have to handle previous models
if self.cfg.get('pretrained_dims') and 'pretrained_vectors' not in self.cfg:
self.cfg['pretrained_vectors'] = self.vocab.vectors.name
if self.model is True:
self.model, cfg = self.Model(**self.cfg)
else:
cfg = {}
if 'model' in msg:
self.model.from_bytes(msg['model'])
self.cfg.update(cfg)
return self