def build(self,
dropout,
char_dim,
char_lstm_dim,
char_bidirect,
word_dim,
word_lstm_dim,
word_bidirect,
lr_method,
pre_emb,
pre_voc,
crf,
pos_dim,
n_pos,
training = 1,
**kwargs
):
"""
Build the network.
"""
# Training parameters
n_words = len(self.id_to_word)
n_chars = len(self.id_to_char)
n_tags = len(self.id_to_y)
n_cap = 2
# Network variables
is_train = T.iscalar('is_train')
word_ids = T.ivector(name='word_ids')
char_for_ids = T.imatrix(name='char_for_ids')
char_rev_ids = T.imatrix(name='char_rev_ids')
char_pos_ids = T.ivector(name='char_pos_ids')
tag_ids = T.ivector(name='tag_ids')
cap_ids = T.ivector(name='cap_ids')
if pos_dim:
pos_ids = T.ivector(name='pos_ids')
# Sentence length
s_len = (word_ids if word_dim else char_pos_ids).shape[0]
# Final input (all word features)
input_dim = 0
inputs = []
#
# Word inputs
#
if word_dim:
input_dim += word_dim
word_layer = EmbeddingLayer(n_words, word_dim, name='word_layer')
word_input = word_layer.link(word_ids)
inputs.append(word_input)
# Initialize with pretrained embeddings
if pre_emb and training:
new_weights = word_layer.embeddings.get_value()
print 'Loading pretrained embeddings from %s...' % pre_emb
pretrained = {}
emb_invalid = 0
emb_matrix = np.load(pre_emb)
pre_w2idxs = dict([(w,i) for i,w in enumerate(np.load(pre_voc))])
print pre_w2idxs.items()[:10]
assert emb_matrix[0].shape[0] == word_dim
for w in pre_w2idxs:
pretrained[w.lower()] = np.array(
[float(x) for x in emb_matrix[pre_w2idxs[w]]]).astype(np.float32)
if emb_invalid > 0:
print 'WARNING: %i invalid lines' % emb_invalid
c_found = 0
c_lower = 0
c_zeros = 0
# Lookup table initialization
for i in xrange(n_words):
word = self.id_to_word[i]
if word in pretrained:
new_weights[i] = pretrained[word]
c_found += 1
elif word.lower() in pretrained:
new_weights[i] = pretrained[word.lower()]
c_lower += 1
elif re.sub('\d', '0', word.lower()) in pretrained:
new_weights[i] = pretrained[
re.sub('\d', '0', word.lower())
]
c_zeros += 1
word_layer.embeddings.set_value(new_weights)
print 'Loaded %i pretrained embeddings.' % len(pretrained)
print ('%i / %i (%.4f%%) words have been initialized with '
'pretrained embeddings.') % (
c_found + c_lower + c_zeros, n_words,
100. * (c_found + c_lower + c_zeros) / n_words
)
print ('%i found directly, %i after lowercasing, '
'%i after lowercasing + zero.') % (
c_found, c_lower, c_zeros
)
#
# Chars inputs
#
if char_dim:
input_dim += char_lstm_dim
char_layer = EmbeddingLayer(n_chars, char_dim, name='char_layer')
char_lstm_for = LSTM(char_dim, char_lstm_dim, with_batch=True,
name='char_lstm_for')
char_lstm_rev = LSTM(char_dim, char_lstm_dim, with_batch=True,
name='char_lstm_rev')
char_lstm_for.link(char_layer.link(char_for_ids))
char_lstm_rev.link(char_layer.link(char_rev_ids))
char_for_output = char_lstm_for.h.dimshuffle((1, 0, 2))[
T.arange(s_len), char_pos_ids
]
char_rev_output = char_lstm_rev.h.dimshuffle((1, 0, 2))[
T.arange(s_len), char_pos_ids
]
inputs.append(char_for_output)
if char_bidirect:
inputs.append(char_rev_output)
input_dim += char_lstm_dim
#
# Cue feature
#
input_dim += word_dim
cap_layer = EmbeddingLayer(n_cap, word_dim, name='cap_layer')
inputs.append(cap_layer.link(cap_ids))
#
# POS feature
#
if pos_dim:
input_dim += word_dim
pos_layer = EmbeddingLayer(n_pos, word_dim, name="pos_layer")
inputs.append(pos_layer.link(pos_ids))
# Prepare final input
# if len(inputs) != 1:
inputs = T.concatenate(inputs, axis=1)
#
# Dropout on final input
#
if dropout:
dropout_layer = DropoutLayer(p=dropout)
input_train = dropout_layer.link(inputs)
input_test = (1 - dropout) * inputs
inputs = T.switch(T.neq(is_train, 0), input_train, input_test)
# LSTM for words
word_lstm_for = LSTM(input_dim, word_lstm_dim, with_batch=False,
name='word_lstm_for')
word_lstm_rev = LSTM(input_dim, word_lstm_dim, with_batch=False,
name='word_lstm_rev')
word_lstm_for.link(inputs)
word_lstm_rev.link(inputs[::-1, :])
word_for_output = word_lstm_for.h
word_rev_output = word_lstm_rev.h[::-1, :]
if word_bidirect:
final_output = T.concatenate(
[word_for_output, word_rev_output],
axis=1
)
tanh_layer = HiddenLayer(2 * word_lstm_dim, word_lstm_dim,
name='tanh_layer', activation='tanh')
final_output = tanh_layer.link(final_output)
else:
final_output = word_for_output
# Sentence to Named Entity tags - Score
final_layer = HiddenLayer(word_lstm_dim, n_tags, name='final_layer',
activation=(None if crf else 'softmax'))
tags_scores = final_layer.link(final_output)
# No CRF
if not crf:
cost = T.nnet.categorical_crossentropy(tags_scores, tag_ids).mean()
# CRF
else:
transitions = shared((n_tags + 2, n_tags + 2), 'transitions')
small = -1000
b_s = np.array([[small] * n_tags + [0, small]]).astype(np.float32)
e_s = np.array([[small] * n_tags + [small, 0]]).astype(np.float32)
observations = T.concatenate(
[tags_scores, small * T.ones((s_len, 2))],
axis=1
)
observations = T.concatenate(
[b_s, observations, e_s],
axis=0
)
# Score from tags
real_path_score = tags_scores[T.arange(s_len), tag_ids].sum()
# Score from transitions
b_id = theano.shared(value=np.array([n_tags], dtype=np.int32))
e_id = theano.shared(value=np.array([n_tags + 1], dtype=np.int32))
padded_tags_ids = T.concatenate([b_id, tag_ids, e_id], axis=0)
real_path_score += transitions[
padded_tags_ids[T.arange(s_len + 1)],
padded_tags_ids[T.arange(s_len + 1) + 1]
].sum()
all_paths_scores = forward(observations, transitions)
cost = - (real_path_score - all_paths_scores)
# Network parameters
params = []
if word_dim:
self.add_component(word_layer)
params.extend(word_layer.params)
if char_dim:
self.add_component(char_layer)
self.add_component(char_lstm_for)
params.extend(char_layer.params)
params.extend(char_lstm_for.params)
if char_bidirect:
self.add_component(char_lstm_rev)
params.extend(char_lstm_rev.params)
self.add_component(word_lstm_for)
params.extend(word_lstm_for.params)
if word_bidirect:
self.add_component(word_lstm_rev)
params.extend(word_lstm_rev.params)
# Add cue layer (cap for the moment)
self.add_component(cap_layer)
params.extend(cap_layer.params)
# Add pos tag layer
if pos_dim:
self.add_component(pos_layer)
params.extend(pos_layer.params)
self.add_component(final_layer)
params.extend(final_layer.params)
if crf:
self.add_component(transitions)
params.append(transitions)
if word_bidirect:
self.add_component(tanh_layer)
params.extend(tanh_layer.params)
# Prepare train and eval inputs
eval_inputs = []
if word_dim:
eval_inputs.append(word_ids)
if char_dim:
eval_inputs.append(char_for_ids)
if char_bidirect:
eval_inputs.append(char_rev_ids)
eval_inputs.append(char_pos_ids)
# add cue vector to the inputs
eval_inputs.append(cap_ids)
# add pos vector to the inputs
if pos_dim:
eval_inputs.append(pos_ids)
train_inputs = eval_inputs + [tag_ids]
# Parse optimization method parameters
if "-" in lr_method:
lr_method_name = lr_method[:lr_method.find('-')]
lr_method_parameters = {}
for x in lr_method[lr_method.find('-') + 1:].split('-'):
split = x.split('_')
assert len(split) == 2
lr_method_parameters[split[0]] = float(split[1])
else:
lr_method_name = lr_method
lr_method_parameters = {}
# Compile training function
print 'Compiling...'
if training:
updates = Optimization(clip=5.0).get_updates(lr_method_name, cost, params, **lr_method_parameters)
f_train = theano.function(
inputs=train_inputs,
outputs=cost,
updates=updates,
givens=({is_train: np.cast['int32'](1)} if dropout else {})
)
else:
f_train = None
# Compile evaluation function
if not crf:
f_eval = theano.function(
inputs=eval_inputs,
outputs=tags_scores,
givens=({is_train: np.cast['int32'](0)} if dropout else {})
)
else:
f_eval = theano.function(
inputs=eval_inputs,
outputs=forward(observations, transitions, viterbi=True,
return_alpha=False, return_best_sequence=True),
givens=({is_train: np.cast['int32'](0)} if dropout else {})
)
return f_train, f_eval
def build(
self,
dropout,
ortho_char_input_dim, # Should be inferred from the input
ortho_char_dim,
ortho_char_lstm_dim,
char_bidirect,
word_vec_input_dim, # Should be inferred from the input wvecs
word_dim, # The vector size after projection of the input vector
word_lstm_dim,
word_bidirect,
lr_method,
crf,
use_type_sparse_feats,
type_sparse_feats_input_dim, # Can be inferred from the output of the feature extractors
type_sparse_feats_proj_dim, # This is a hyper-parameter
use_token_sparse_feats,
token_sparse_feats_input_dim, # Can be inferred from the output of the feature extractors
# token_sparse_feats_proj_dim, # This is a hyper-parameter
use_ortho_attention,
use_phono_attention,
# use_convolution,
phono_char_input_dim, # Can be inferred
phono_char_dim,
phono_char_lstm_dim,
training=True,
**kwargs):
"""
Build the network.
"""
assert word_dim or phono_char_dim or ortho_char_dim, "No input selected while building the network!"
# Training parameters
n_tags = len(self.id_to_tag)
# Network variables
is_train = T.iscalar('is_train')
word_vecs = T.dmatrix(
name="word_vecs") # A vector for each word in the sentence
# => matrix: (len_sent, w_emb_dim)
ortho_char_for_vecs = T.dtensor3(
name="ortho_char_for_vecs"
) # For each char of each word in the sentence, a char vector
# ortho_char_for_vecs = T.ftensor3(name="ortho_char_for_vecs")
# => tensor of form: (len_sent, max_wchar_len, char_emb_dim)
ortho_char_rev_vecs = T.dtensor3(name="ortho_char_rev_vecs")
# ortho_char_rev_vecs = T.ftensor3(name="ortho_char_rev_vecs")
# For each char of each word in the sentence, a char vector
# => tensor of form: (len_sent, max_wchar_len, char_emb_dim)
phono_char_for_vecs = T.dtensor3(name="phono_char_for_vecs")
# phono_char_for_vecs = T.ftensor3(name="phono_char_for_vecs")
# For each char of each word in the sentence, a char vector
# => tensor of form: (len_sent, max_ortho_char_len, char_emb_dim)
phono_char_rev_vecs = T.dtensor3(name="phono_char_rev_vecs")
# phono_char_rev_vecs = T.ftensor3(name="phono_char_rev_vecs")
# For each char of each word in the sentence, a char vector
# => tensor of form: (len_sent, max_phono_char_len, char_emb_dim)
ortho_char_pos_ids = T.ivector(name='ortho_char_pos_ids')
# The word len for each word in the sentence => vect of form: (len_sent,)
phono_char_pos_ids = T.ivector(name='phono_char_pos_ids')
# The word len for each word in the sentence => vect of form: (len_sent,)
type_sparse_feats = T.imatrix(name="type_sparse_feats")
# Type sparse features are appended to the input to the word lstm
# For each word, a vector of type level sparse feats => mat of form: (len_sent, type_sparse_dim)
token_sparse_feats = T.imatrix(name="token_sparse_feats")
# Token sparse features are appended to the pre-crf layer
# For each word, a vector of token level sparse feats => mat of form: (len_sent, token_sparse_dim)
tag_ids = T.ivector(name='tag_ids')
# The tag id for each word in the sentence => vect of form: (len_sent,)
# Sentence length
s_len = (word_vecs if word_dim else ortho_char_pos_ids
if ortho_char_dim else phono_char_pos_ids).shape[0]
# Final input (all word features)
input_dim = 0
inputs = []
#
# Word inputs
#
if word_dim:
input_dim += word_dim
word_layer = HiddenLayer(word_vec_input_dim,
word_dim,
activation="tanh",
name="word_emb_proj")
# TO DO : Try not using the bias term in the hidden layer
word_input = word_layer.link(word_vecs)
inputs.append(word_input)
#
# Chars inputs
#
if ortho_char_dim:
input_dim += ortho_char_lstm_dim
ortho_char_layer = HiddenLayer(ortho_char_input_dim,
ortho_char_dim,
activation="tanh",
name="ortho_char_emb_proj")
# TO DO : Try not using bias in the hidden layer
ortho_char_lstm_for = LSTM(ortho_char_dim,
ortho_char_lstm_dim,
with_batch=True,
name='ortho_char_lstm_for')
ortho_char_lstm_rev = LSTM(ortho_char_dim,
ortho_char_lstm_dim,
with_batch=True,
name='ortho_char_lstm_rev')
ortho_char_lstm_for.link(
ortho_char_layer.link(ortho_char_for_vecs))
ortho_char_lstm_rev.link(
ortho_char_layer.link(ortho_char_rev_vecs))
ortho_char_for_output = ortho_char_lstm_for.h.dimshuffle(
(1, 0, 2))[T.arange(s_len), ortho_char_pos_ids]
ortho_char_rev_output = ortho_char_lstm_rev.h.dimshuffle(
(1, 0, 2))[T.arange(s_len), ortho_char_pos_ids]
inputs.append(ortho_char_for_output)
if char_bidirect:
inputs.append(ortho_char_rev_output)
input_dim += ortho_char_lstm_dim
if phono_char_dim:
input_dim += phono_char_lstm_dim
phono_char_layer = HiddenLayer(phono_char_input_dim,
phono_char_dim,
activation="tanh",
name="phono_char_emb_proj")
# TO DO : Try not using bias in the hidden layer
phono_char_lstm_for = LSTM(phono_char_dim,
phono_char_lstm_dim,
with_batch=True,
name='phono_char_lstm_for')
phono_char_lstm_rev = LSTM(phono_char_dim,
phono_char_lstm_dim,
with_batch=True,
name='phono_char_lstm_rev')
phono_char_lstm_for.link(
phono_char_layer.link(phono_char_for_vecs))
phono_char_lstm_rev.link(
phono_char_layer.link(phono_char_rev_vecs))
phono_char_for_output = phono_char_lstm_for.h.dimshuffle(
(1, 0, 2))[T.arange(s_len), phono_char_pos_ids]
phono_char_rev_output = phono_char_lstm_rev.h.dimshuffle(
(1, 0, 2))[T.arange(s_len), phono_char_pos_ids]
inputs.append(phono_char_for_output)
if char_bidirect:
inputs.append(phono_char_rev_output)
input_dim += phono_char_lstm_dim
# Type level sparse feats
#
if use_type_sparse_feats:
input_dim += type_sparse_feats_input_dim
type_level_sparse_layer = HiddenLayer(
type_sparse_feats_input_dim,
type_sparse_feats_proj_dim,
activation="tanh",
name='type_level_sparse_layer')
# TO DO : Try not using the hidden layer here
inputs.append(type_level_sparse_layer.link(type_sparse_feats))
# Prepare final input
if len(inputs) != 1:
inputs = T.concatenate(inputs, axis=1)
# TO DO : If using type sparse features, then apply hidden layer after concatenating all inputs
else:
inputs = inputs[0]
#
# Dropout on final input
#
if dropout:
dropout_layer = DropoutLayer(p=dropout)
input_train = dropout_layer.link(inputs)
input_test = (1 - dropout) * inputs
"""
Drop out involves sampling a vector of bernoulli random variables with a parameter 1-p and using it as a mask
So, the expected value of the dropped out input is p * (0*x) + (1-p) * (1*x) = (1-p) * x. Since biases will
on average respond to the expected input value, at test time we multiply test inputs (1-p) to supply the
expected test input instead.
"""
inputs = T.switch(T.neq(is_train, 0), input_train, input_test)
# LSTM for words
word_lstm_for = LSTM(input_dim,
word_lstm_dim,
with_batch=False,
name='word_lstm_for')
word_lstm_rev = LSTM(input_dim,
word_lstm_dim,
with_batch=False,
name='word_lstm_rev')
word_lstm_for.link(inputs)
word_lstm_rev.link(inputs[::-1, :])
word_for_output = word_lstm_for.h
word_rev_output = word_lstm_rev.h[::-1, :]
lstm_outputs = [word_for_output]
post_word_lstm_output_size = word_lstm_dim
if use_token_sparse_feats:
# token_level_sparse_layer = HiddenLayer(token_sparse_feats_input_dim, token_sparse_feats_proj_dim,
# activation="tanh",
# name='token_level_sparse_layer')
# # TO DO : Try not using the hidden layer here
# lstm_outputs.append(token_level_sparse_layer.link(token_sparse_feats))
# post_word_lstm_output_size += token_sparse_feats_proj_dim
lstm_outputs.append(token_sparse_feats)
post_word_lstm_output_size += token_sparse_feats_input_dim
if word_bidirect:
lstm_outputs.append(word_rev_output)
post_word_lstm_output_size += word_lstm_dim
if len(lstm_outputs) > 1:
final_output = T.concatenate(lstm_outputs, axis=1)
tanh_layer = HiddenLayer(post_word_lstm_output_size,
word_lstm_dim,
name='tanh_layer',
activation='tanh')
final_output = tanh_layer.link(final_output)
else:
final_output = word_for_output
final_pre_crf_input_size = word_lstm_dim
attention_vectors = []
attention_vector_size = 0
if use_ortho_attention and ortho_char_dim:
# final_ortho_attention_input_layer = HiddenLayer(post_word_lstm_output_size, ortho_char_lstm_dim,
# name='final_ortho_attention_input_layer', activation='tanh')
final_ortho_attention_input_layer = HiddenLayer(
word_lstm_dim,
ortho_char_lstm_dim,
name='final_ortho_attention_input_layer',
activation='tanh')
final_ortho_attention_input = final_ortho_attention_input_layer.link(
final_output)
# Evaluating attentional vector using a linear projection from final_output since the attention vector
# must be conditioned on it and dimension must match the char lstm hidden dim.
ortho_for_attention = self.get_TDAttention_vector(
final_ortho_attention_input,
ortho_char_lstm_for.h.dimshuffle((1, 0, 2)),
ortho_char_pos_ids)
if char_bidirect:
ortho_rev_attention = self.get_TDAttention_vector(
final_ortho_attention_input,
ortho_char_lstm_rev.h.dimshuffle((1, 0, 2)),
ortho_char_pos_ids)
attention_vectors.append(ortho_rev_attention)
attention_vector_size += ortho_char_lstm_dim
attention_vectors.append(ortho_for_attention)
attention_vector_size += ortho_char_lstm_dim
if use_phono_attention and phono_char_dim:
# final_phono_attention_input_layer = HiddenLayer(post_word_lstm_output_size, phono_char_lstm_dim,
# name='final_phono_attention_input_layer', activation='tanh')
final_phono_attention_input_layer = HiddenLayer(
word_lstm_dim,
phono_char_lstm_dim,
name='final_phono_attention_input_layer',
activation='tanh')
# Evaluating attentional vector using a linear projection from final_output since the attention vector
# must be conditioned on it and dimension must match the char lstm hidden dim.
final_phono_attention_input = final_phono_attention_input_layer.link(
final_output)
phono_for_attention = self.get_TDAttention_vector(
final_phono_attention_input,
phono_char_lstm_for.h.dimshuffle((1, 0, 2)),
phono_char_pos_ids)
if char_bidirect:
phono_rev_attention = self.get_TDAttention_vector(
final_phono_attention_input,
phono_char_lstm_rev.h.dimshuffle((1, 0, 2)),
phono_char_pos_ids)
attention_vectors.append(phono_rev_attention)
attention_vector_size += phono_char_lstm_dim
attention_vectors.append(phono_for_attention)
attention_vector_size += phono_char_lstm_dim
if len(attention_vectors) > 1:
attention_vectors = T.concatenate(attention_vectors, axis=1)
if use_phono_attention or use_ortho_attention:
final_output = T.concatenate([final_output, attention_vectors],
axis=1)
post_word_lstm_output_size += attention_vector_size
final_pre_crf_input_size += attention_vector_size
# Sentence to Named Entity tags - Score
final_layer = HiddenLayer(final_pre_crf_input_size,
n_tags,
name='final_layer',
activation=(None if crf else 'softmax'))
tags_scores = final_layer.link(final_output)
# No CRF
if not crf:
cost = T.nnet.categorical_crossentropy(tags_scores, tag_ids).mean()
# CRF
else:
transitions = shared((n_tags + 2, n_tags + 2), 'transitions')
# n_tags + 2 to accommodate start and end symbols
small = -1000 # = -log(inf)
b_s = np.array([[small] * n_tags + [0, small]]).astype(np.float32)
# Score of starting at start symbol is 1 => -log(1) = 0. Score of start symbol emitting any other NER
# tag is -log(inf) = small
e_s = np.array([[small] * n_tags + [small, 0]]).astype(np.float32)
# Score of ending at end symbol is 1 => -log(1) = 0. Score of end symbol emitting any other NER
# tag is -log(inf) = small
observations = T.concatenate(
[tags_scores, small * T.ones((s_len, 2))], axis=1)
# observations is the emission energy (-log potential) between each token and each tag.
# Emission score of intermediate words towards start and end tags is -log(inf)
observations = T.concatenate([b_s, observations, e_s], axis=0)
# observations now contains the emission energies for start token, sentence tokens and end token
# Score from tags
real_path_score = tags_scores[T.arange(s_len), tag_ids].sum()
# Sum of energies associated with the gold tags
# Score from transitions
b_id = theano.shared(value=np.array([n_tags], dtype=np.int32))
e_id = theano.shared(value=np.array([n_tags + 1], dtype=np.int32))
padded_tags_ids = T.concatenate([b_id, tag_ids, e_id], axis=0)
real_path_score += transitions[padded_tags_ids[T.arange(s_len +
1)],
padded_tags_ids[T.arange(s_len + 1)
+ 1]].sum()
# Transition scores from label_i to label_{i+1}
all_paths_scores = forward(observations, transitions)
cost = -(real_path_score - all_paths_scores)
# Network parameters
params = []
if word_dim:
self.add_component(word_layer)
params.extend(word_layer.params)
if ortho_char_dim:
self.add_component(ortho_char_layer)
self.add_component(ortho_char_lstm_for)
params.extend(ortho_char_layer.params)
params.extend(ortho_char_lstm_for.params)
if char_bidirect:
self.add_component(ortho_char_lstm_rev)
params.extend(ortho_char_lstm_rev.params)
if phono_char_dim:
self.add_component(phono_char_layer)
self.add_component(phono_char_lstm_for)
params.extend(phono_char_layer.params)
params.extend(phono_char_lstm_for.params)
if char_bidirect:
self.add_component(phono_char_lstm_rev)
params.extend(phono_char_lstm_rev.params)
if use_type_sparse_feats:
self.add_component(type_level_sparse_layer)
params.extend(type_level_sparse_layer.params)
self.add_component(word_lstm_for)
params.extend(word_lstm_for.params)
if word_bidirect:
self.add_component(word_lstm_rev)
params.extend(word_lstm_rev.params)
if word_bidirect or len(lstm_outputs) > 1:
self.add_component(tanh_layer)
params.extend(tanh_layer.params)
if use_ortho_attention and ortho_char_dim:
self.add_component(final_ortho_attention_input_layer)
params.extend(final_ortho_attention_input_layer.params)
if use_phono_attention and phono_char_dim:
self.add_component(final_phono_attention_input_layer)
params.extend(final_phono_attention_input_layer.params)
self.add_component(final_layer)
params.extend(final_layer.params)
if crf:
self.add_component(transitions)
params.append(transitions)
# Prepare train and eval inputs
eval_inputs = []
if word_dim:
# eval_inputs.append(word_ids)
eval_inputs.append(word_vecs)
if ortho_char_dim:
# eval_inputs.append(char_for_ids)
eval_inputs.append(ortho_char_for_vecs)
if char_bidirect:
# eval_inputs.append(char_rev_ids)
eval_inputs.append(ortho_char_rev_vecs)
eval_inputs.append(ortho_char_pos_ids)
if phono_char_dim:
# eval_inputs.append(char_for_ids)
eval_inputs.append(phono_char_for_vecs)
if char_bidirect:
# eval_inputs.append(char_rev_ids)
eval_inputs.append(phono_char_rev_vecs)
eval_inputs.append(phono_char_pos_ids)
if use_type_sparse_feats:
eval_inputs.append(type_sparse_feats)
if use_token_sparse_feats:
eval_inputs.append(token_sparse_feats)
train_inputs = eval_inputs + [tag_ids]
# Parse optimization method parameters
if "-" in lr_method:
lr_method_name = lr_method[:lr_method.find('-')]
lr_method_parameters = {}
for x in lr_method[lr_method.find('-') + 1:].split('-'):
split = x.split('_')
assert len(split) == 2
lr_method_parameters[split[0]] = float(split[1])
else:
lr_method_name = lr_method
lr_method_parameters = {}
# Compile training function
print 'Compiling...'
if training:
updates = Optimization(clip=5.0).get_updates(
lr_method_name, cost, params, **lr_method_parameters)
f_train = theano.function(inputs=train_inputs,
outputs=cost,
updates=updates,
givens=({
is_train: np.cast['int32'](1)
} if dropout else {}))
else:
f_train = None
# Compile evaluation function
if not crf:
f_eval = theano.function(inputs=eval_inputs,
outputs=tags_scores,
givens=({
is_train: np.cast['int32'](0)
} if dropout else {}))
else:
f_eval = theano.function(inputs=eval_inputs,
outputs=forward(
observations,
transitions,
viterbi=True,
return_alpha=False,
return_best_sequence=True),
givens=({
is_train: np.cast['int32'](0)
} if dropout else {}))
print("Finished Compiling")
return f_train, f_eval
def build(self,
dropout,
char_dim,
char_lstm_dim,
char_bidirect,
word_dim,
word_lstm_dim,
word_bidirect,
lr_method,
pre_emb,
crf,
cap_dim,
training=True,
**kwargs):
"""
Build the network.
"""
# Training parameters
n_words = len(self.id_to_word)
n_chars = len(self.id_to_char)
n_tags = len(self.id_to_tag)
# Number of capitalization features
if cap_dim:
n_cap = 4
# Network variables
is_train = T.iscalar('is_train')
word_ids = T.ivector(name='word_ids')
char_for_ids = T.imatrix(name='char_for_ids')
char_rev_ids = T.imatrix(name='char_rev_ids')
char_pos_ids = T.ivector(name='char_pos_ids')
tag_ids = T.ivector(name='tag_ids')
if cap_dim:
cap_ids = T.ivector(name='cap_ids')
# Sentence length
s_len = (word_ids if word_dim else char_pos_ids).shape[0]
# Final input (all word features)
input_dim = 0
inputs = []
#
# Word inputs
#
if word_dim:
input_dim += word_dim
word_layer = EmbeddingLayer(n_words, word_dim, name='word_layer')
word_input = word_layer.link(word_ids)
inputs.append(word_input)
# Initialize with pretrained embeddings
if pre_emb and training:
new_weights = word_layer.embeddings.get_value()
print 'Loading pretrained embeddings from %s...' % pre_emb
pretrained = {}
emb_invalid = 0
#for i, line in enumerate(codecs.open(pre_emb, 'r', 'utf-8')):
for i, line in enumerate(codecs.open(pre_emb, 'r', 'utf-8')):
line = line.rstrip().split()
if len(line) == word_dim + 1:
pretrained[line[0]] = np.array(
[float(x) for x in line[1:]]).astype(np.float32)
else:
emb_invalid += 1
if emb_invalid > 0:
print 'WARNING: %i invalid lines' % emb_invalid
c_found = 0
c_lower = 0
c_zeros = 0
# Lookup table initialization
for i in xrange(n_words):
word = self.id_to_word[i]
if word in pretrained:
new_weights[i] = pretrained[word]
c_found += 1
elif word.lower() in pretrained:
new_weights[i] = pretrained[word.lower()]
c_lower += 1
elif re.sub('\d', '0', word.lower()) in pretrained:
new_weights[i] = pretrained[re.sub(
'\d', '0', word.lower())]
c_zeros += 1
word_layer.embeddings.set_value(new_weights)
print 'Loaded %i pretrained embeddings.' % len(pretrained)
print(
'%i / %i (%.4f%%) words have been initialized with '
'pretrained embeddings.') % (
c_found + c_lower + c_zeros, n_words, 100. *
(c_found + c_lower + c_zeros) / n_words)
print(
'%i found directly, %i after lowercasing, '
'%i after lowercasing + zero.') % (c_found, c_lower,
c_zeros)
#
# Chars inputs
#
if char_dim:
input_dim += char_lstm_dim
char_layer = EmbeddingLayer(n_chars, char_dim, name='char_layer')
char_lstm_for = LSTM(char_dim,
char_lstm_dim,
with_batch=True,
name='char_lstm_for')
char_lstm_rev = LSTM(char_dim,
char_lstm_dim,
with_batch=True,
name='char_lstm_rev')
char_lstm_for.link(char_layer.link(char_for_ids))
char_lstm_rev.link(char_layer.link(char_rev_ids))
char_for_output = char_lstm_for.h.dimshuffle(
(1, 0, 2))[T.arange(s_len), char_pos_ids]
char_rev_output = char_lstm_rev.h.dimshuffle(
(1, 0, 2))[T.arange(s_len), char_pos_ids]
inputs.append(char_for_output)
if char_bidirect:
inputs.append(char_rev_output)
input_dim += char_lstm_dim
#
# Capitalization feature
#
if cap_dim:
input_dim += cap_dim
cap_layer = EmbeddingLayer(n_cap, cap_dim, name='cap_layer')
inputs.append(cap_layer.link(cap_ids))
# Prepare final input
if len(inputs) != 1:
inputs = T.concatenate(inputs, axis=1)
#
# Dropout on final input
#
if dropout:
dropout_layer = DropoutLayer(p=dropout)
input_train = dropout_layer.link(inputs)
input_test = (1 - dropout) * inputs
inputs = T.switch(T.neq(is_train, 0), input_train, input_test)
# LSTM for words
word_lstm_for = LSTM(input_dim,
word_lstm_dim,
with_batch=False,
name='word_lstm_for')
word_lstm_rev = LSTM(input_dim,
word_lstm_dim,
with_batch=False,
name='word_lstm_rev')
word_lstm_for.link(inputs)
word_lstm_rev.link(inputs[::-1, :])
word_for_output = word_lstm_for.h
word_rev_output = word_lstm_rev.h[::-1, :]
if word_bidirect:
final_output = T.concatenate([word_for_output, word_rev_output],
axis=1)
tanh_layer = HiddenLayer(2 * word_lstm_dim,
word_lstm_dim,
name='tanh_layer',
activation='tanh')
final_output = tanh_layer.link(final_output)
else:
final_output = word_for_output
# Sentence to Named Entity tags - Score
final_layer = HiddenLayer(word_lstm_dim,
n_tags,
name='final_layer',
activation=(None if crf else 'softmax'))
tags_scores = final_layer.link(final_output)
# No CRF
if not crf:
cost = T.nnet.categorical_crossentropy(tags_scores, tag_ids).mean()
# CRF
else:
transitions = shared((n_tags + 2, n_tags + 2), 'transitions')
small = -1000
b_s = np.array([[small] * n_tags + [0, small]]).astype(np.float32)
e_s = np.array([[small] * n_tags + [small, 0]]).astype(np.float32)
#s_len # of words in sentence
observations = T.concatenate(
[tags_scores, small * T.ones((s_len, 2))], axis=1)
#add padding to exist tag_scores(sentencelength * tag_ids)
observations = T.concatenate([b_s, observations, e_s], axis=0)
# Score from tags
real_path_score = tags_scores[T.arange(s_len), tag_ids].sum()
# Score from transitions
b_id = theano.shared(value=np.array([n_tags], dtype=np.int32))
e_id = theano.shared(value=np.array([n_tags + 1], dtype=np.int32))
padded_tags_ids = T.concatenate([b_id, tag_ids, e_id], axis=0)
real_path_score += transitions[padded_tags_ids[T.arange(s_len +
1)],
padded_tags_ids[T.arange(s_len + 1)
+ 1]].sum()
all_paths_scores = forward(observations, transitions)
cost = -(real_path_score - all_paths_scores)
# Network parameters
params = []
if word_dim:
self.add_component(word_layer)
params.extend(word_layer.params)
if char_dim:
self.add_component(char_layer)
self.add_component(char_lstm_for)
params.extend(char_layer.params)
params.extend(char_lstm_for.params)
if char_bidirect:
self.add_component(char_lstm_rev)
params.extend(char_lstm_rev.params)
self.add_component(word_lstm_for)
params.extend(word_lstm_for.params)
if word_bidirect:
self.add_component(word_lstm_rev)
params.extend(word_lstm_rev.params)
if cap_dim:
self.add_component(cap_layer)
params.extend(cap_layer.params)
self.add_component(final_layer)
params.extend(final_layer.params)
if crf:
self.add_component(transitions)
params.append(transitions)
if word_bidirect:
self.add_component(tanh_layer)
params.extend(tanh_layer.params)
# Prepare train and eval inputs
eval_inputs = []
if word_dim:
eval_inputs.append(word_ids)
if char_dim:
eval_inputs.append(char_for_ids)
if char_bidirect:
eval_inputs.append(char_rev_ids)
eval_inputs.append(char_pos_ids)
if cap_dim:
eval_inputs.append(cap_ids)
train_inputs = eval_inputs + [tag_ids]
# Parse optimization method parameters
if "-" in lr_method:
lr_method_name = lr_method[:lr_method.find('-')]
lr_method_parameters = {}
for x in lr_method[lr_method.find('-') + 1:].split('-'):
split = x.split('_')
assert len(split) == 2
lr_method_parameters[split[0]] = float(split[1])
else:
lr_method_name = lr_method
lr_method_parameters = {}
# Compile training function
print 'Compiling...'
if training:
updates = Optimization(clip=5.0).get_updates(
lr_method_name, cost, params, **lr_method_parameters)
f_train = theano.function(inputs=train_inputs,
outputs=cost,
updates=updates,
givens=({
is_train: np.cast['int32'](1)
} if dropout else {}))
else:
f_train = None
# Compile evaluation function
if not crf:
f_eval = theano.function(inputs=eval_inputs,
outputs=tags_scores,
givens=({
is_train: np.cast['int32'](0)
} if dropout else {}))
else:
f_eval = theano.function(inputs=eval_inputs,
outputs=forward(
observations,
transitions,
viterbi=True,
return_alpha=False,
return_best_sequence=True),
givens=({
is_train: np.cast['int32'](0)
} if dropout else {}))
return f_train, f_eval
def build(
self,
dropout,
char_dim,
char_hidden_dim,
char_bidirect,
word_dim,
word_hidden_dim,
word_bidirect,
tagger_hidden_dim,
hamming_cost,
L2_reg,
lr_method,
pre_word_emb,
pre_char_emb,
tagger,
use_gaze,
POS,
plot_cost,
#cap_dim,
training=True,
**kwargs):
"""
Build the network.
"""
# Training parameters
n_words = len(self.id_to_word)
n_chars = len(self.id_to_char)
n_tags = len(self.id_to_tag)
# n_pos = len(self.id_to_pos) + 1
# Number of capitalization features
#if cap_dim:
# n_cap = 4
# Network variables
is_train = T.iscalar('is_train') # declare variable,声明整型变量is_train
word_ids = T.ivector(name='word_ids') #声明整型一维向量
char_for_ids = T.imatrix(name='char_for_ids') # 声明整型二维矩阵
char_rev_ids = T.imatrix(name='char_rev_ids')
char_pos_ids = T.ivector(name='char_pos_ids')
if use_gaze:
gaze = T.imatrix(name='gaze')
if POS:
# pos_ids = T.ivector(name='pos_ids')
pos_one_hot = T.imatrix(name='pos_one_hot')
#hamming_cost = T.matrix('hamming_cost', theano.config.floatX) # 声明整型二维矩阵
tag_ids = T.ivector(name='tag_ids')
#if cap_dim:
# cap_ids = T.ivector(name='cap_ids')
# Sentence length
s_len = (word_ids if word_dim else char_pos_ids).shape[0] #句子中的单词数
# Final input (all word features)
input_dim = 0
inputs = []
L2_norm = 0.0
theano.config.compute_test_value = 'off'
#
# Word inputs
#
if word_dim:
input_dim += word_dim
word_layer = EmbeddingLayer(n_words, word_dim, name='word_layer')
word_input = word_layer.link(word_ids)
inputs.append(word_input)
# Initialize with pretrained embeddings
if pre_word_emb and training:
new_weights = word_layer.embeddings.get_value()
print 'Loading pretrained word embeddings from %s...' % pre_word_emb
pretrained = {}
emb_invalid = 0
for i, line in enumerate(
codecs.open(pre_word_emb, 'r', 'utf-8', 'ignore')):
line = line.rstrip().split()
if len(line) == word_dim + 1:
pretrained[line[0]] = np.array(
[float(x) for x in line[1:]]).astype(np.float32)
else:
emb_invalid += 1
if emb_invalid > 0:
print 'WARNING: %i invalid word embedding lines' % emb_invalid
c_found = 0
c_lower = 0
c_zeros = 0
# Lookup table initialization
for i in xrange(n_words):
word = self.id_to_word[i]
if word in pretrained:
new_weights[i] = pretrained[word]
c_found += 1
elif word.lower() in pretrained:
new_weights[i] = pretrained[word.lower()]
c_lower += 1
elif re.sub('\d', '0', word) in pretrained:
new_weights[i] = pretrained[re.sub('\d', '0', word)]
c_zeros += 1
word_layer.embeddings.set_value(new_weights)
print 'Loaded %i pretrained word embeddings.' % len(pretrained)
print(
'%i / %i (%.4f%%) words have been initialized with '
'pretrained word embeddings.') % (
c_found + c_lower + c_zeros, n_words, 100. *
(c_found + c_lower + c_zeros) / n_words)
print('%i found directly, %i after lowercasing + zero.') % (
c_found, c_lower + c_zeros)
L2_norm += (word_layer.embeddings**2).sum()
#
# Chars inputs
#
if char_dim:
input_dim += char_hidden_dim
char_layer = EmbeddingLayer(n_chars, char_dim, name='char_layer')
char_for_input = char_layer.link(char_for_ids)
char_rev_input = char_layer.link(char_rev_ids)
# Initialize with pretrained char embeddings
if pre_char_emb and training:
new_weights = char_layer.embeddings.get_value()
print 'Loading pretrained char embeddings from %s...' % pre_char_emb
pretrained = {}
emb_invalid = 0
for i, line in enumerate(
codecs.open(pre_char_emb, 'r', 'utf-8', 'ignore')):
line = line.rstrip().split()
if len(line) == char_dim + 1:
pretrained[line[0]] = np.array(
[float(x) for x in line[1:]]).astype(np.float32)
else:
emb_invalid += 1
if emb_invalid > 0:
print 'WARNING: %i invalid char embedding lines' % emb_invalid
c_found = 0
c_lower = 0
c_zeros = 0
# Lookup table initialization
for i in xrange(n_chars):
char = self.id_to_char[i]
if char in pretrained:
new_weights[i] = pretrained[char]
c_found += 1
elif word.lower() in pretrained:
new_weights[i] = pretrained[word.lower()]
c_lower += 1
elif re.sub('\d', '0', char) in pretrained:
new_weights[i] = pretrained[re.sub('\d', '0', char)]
c_zeros += 1
char_layer.embeddings.set_value(new_weights)
print 'Loaded %i pretrained char embeddings.' % len(pretrained)
print(
'%i / %i (%.4f%%) words have been initialized with '
'pretrained char embeddings.') % (
c_found + c_lower + c_zeros, n_chars, 100. *
(c_found + +c_lower + c_zeros) / n_chars)
print('%i found directly, %i after lowercasing + zero.') % (
c_found, c_lower + c_zeros)
L2_norm += (char_layer.embeddings**2).sum()
char_lstm_for = LSTM(char_dim,
char_hidden_dim,
with_batch=True,
name='char_lstm_for')
char_lstm_rev = LSTM(char_dim,
char_hidden_dim,
with_batch=True,
name='char_lstm_rev')
char_lstm_for.link(char_for_input)
char_lstm_rev.link(char_rev_input)
char_for_output = char_lstm_for.h.dimshuffle(
(1, 0, 2))[T.arange(s_len), char_pos_ids]
char_rev_output = char_lstm_rev.h.dimshuffle(
(1, 0, 2))[T.arange(s_len), char_pos_ids]
for param in char_lstm_for.params[:8]:
L2_norm += (param**2).sum()
if char_bidirect:
char_lstm_hidden = T.concatenate(
[char_for_output, char_rev_output], axis=1)
input_dim += char_hidden_dim
for param in char_lstm_rev.params[:8]:
L2_norm += (param**2).sum()
else:
char_lstm_hidden = char_for_output
inputs.append(char_lstm_hidden)
# if POS:
# pos_dim = 20
# input_dim += pos_dim
# pos_layer = EmbeddingLayer(n_pos, pos_dim, name='pos_layer')
# pos_input = pos_layer.link(pos_ids)
# inputs.append(pos_input)
# L2_norm += (pos_layer.embeddings ** 2).sum()
#if len(inputs) != 1:
inputs = T.concatenate(inputs, axis=1)
#
# Dropout on final input
#
if dropout:
dropout_layer = DropoutLayer(p=dropout)
input_train = dropout_layer.link(inputs)
input_test = (1 - dropout) * inputs
inputs = T.switch(T.neq(is_train, 0), input_train,
input_test) # 条件句
# if POS:
# inputs = T.concatenate([inputs, pos_one_hot], axis= 1)
# input_dim += 6
# LSTM for words
word_lstm_for = LSTM(input_dim,
word_hidden_dim,
with_batch=False,
name='word_lstm_for')
word_lstm_rev = LSTM(input_dim,
word_hidden_dim,
with_batch=False,
name='word_lstm_rev')
word_lstm_for.link(inputs) # 单词的顺序： I like dog
word_lstm_rev.link(inputs[::-1, :]) # 单词的顺序： dog like I
word_for_output = word_lstm_for.h
word_rev_output = word_lstm_rev.h[::-1, :]
for param in word_lstm_for.params[:8]:
L2_norm += (param**2).sum()
if word_bidirect:
final_output = T.concatenate([word_for_output, word_rev_output],
axis=1)
tanh_layer = HiddenLayer(2 * word_hidden_dim,
word_hidden_dim,
name='tanh_layer',
activation='tanh')
final_output = tanh_layer.link(final_output)
for param in word_lstm_rev.params[:8]:
L2_norm += (param**2).sum()
else:
final_output = word_for_output
dims = word_hidden_dim
if use_gaze:
final_output = T.concatenate([final_output, gaze], axis=1)
dims = word_hidden_dim + n_tags
if POS:
final_output = T.concatenate([final_output, pos_one_hot], axis=1)
dims += 6
# if word_bidirect:
# final_output = T.concatenate(
# [word_for_output, word_rev_output],
# axis=1
# )
# tanh_layer = HiddenLayer(2 * word_hidden_dim, word_hidden_dim,
# name='tanh_layer', activation='tanh')
# final_output = tanh_layer.link(final_output)
# else:
# final_output = word_for_output
# Sentence to Named Entity tags
## final_layer = HiddenLayer(dims, n_tags, name='final_layer',
## activation=(None if crf else 'softmax'))
# final_layer = HiddenLayer(word_hidden_dim, n_tags, name='final_layer',
# activation=(None if crf else 'softmax'))
## tags_scores = final_layer.link(final_output)
## L2_norm += (final_layer.params[0] ** 2).sum()
# No CRF
if tagger == 'lstm':
tagger_layer = LSTM_d(dims,
tagger_hidden_dim,
with_batch=False,
name='LSTM_d')
tagger_layer.link(final_output)
final_output = tagger_layer.t
dims = tagger_hidden_dim
for param in tagger_layer.params[:8]:
L2_norm += (param**2).sum()
final_layer = HiddenLayer(
dims,
n_tags,
name='final_layer',
activation=(None if tagger == 'crf' else 'softmax'))
tags_scores = final_layer.link(final_output)
L2_norm += (final_layer.params[0]**2).sum()
if tagger != 'crf':
cost = T.nnet.categorical_crossentropy(tags_scores, tag_ids).mean()
# CRF
else:
transitions = shared((n_tags + 2, n_tags + 2), 'transitions')
small = -1000
b_s = np.array([[small] * n_tags + [0, small]]).astype(np.float32)
e_s = np.array([[small] * n_tags + [small, 0]]).astype(np.float32)
observations = T.concatenate(
[tags_scores, small * T.ones((s_len, 2))], axis=1)
observations = T.concatenate([b_s, observations, e_s], axis=0)
# Score from tags
real_path_score = tags_scores[T.arange(s_len),
tag_ids].sum() # P中对应元素的求和好
# Score from add_componentnsitions
b_id = theano.shared(value=np.array([n_tags], dtype=np.int32))
e_id = theano.shared(value=np.array([n_tags + 1], dtype=np.int32))
padded_tags_ids = T.concatenate([b_id, tag_ids, e_id], axis=0)
real_path_score += transitions[
padded_tags_ids[T.arange(s_len + 1)],
padded_tags_ids[T.arange(s_len + 1) + 1]].sum() # A中对应元素的求和
all_paths_scores = forward(observations,
transitions,
hamming_cost=hamming_cost,
n_tags=n_tags,
padded_tags_ids=padded_tags_ids)
L2_norm += (transitions**2).sum()
cost = -(real_path_score - all_paths_scores) + L2_reg * L2_norm
# Network parameters
params = []
if word_dim:
self.add_component(word_layer)
params.extend(word_layer.params)
if char_dim:
self.add_component(char_layer)
params.extend(char_layer.params)
self.add_component(char_lstm_for)
params.extend(char_lstm_for.params)
if char_bidirect:
self.add_component(char_lstm_rev)
params.extend(char_lstm_rev.params)
self.add_component(word_lstm_for)
params.extend(word_lstm_for.params)
# if POS:
# self.add_component(pos_layer)
# params.extend(pos_layer.params)
if word_bidirect:
self.add_component(word_lstm_rev)
params.extend(word_lstm_rev.params)
self.add_component(final_layer)
params.extend(final_layer.params)
if tagger == 'lstm':
self.add_component(tagger_layer)
params.extend(tagger_layer.params)
elif tagger == 'crf':
self.add_component(transitions)
params.append(transitions)
if word_bidirect:
self.add_component(tanh_layer)
params.extend(tanh_layer.params)
# Prepare train and eval inputs
eval_inputs = []
if word_dim:
eval_inputs.append(word_ids)
if use_gaze:
eval_inputs.append(gaze)
if POS:
# eval_inputs.append(pos_ids)
eval_inputs.append(pos_one_hot)
if char_dim:
eval_inputs.append(char_for_ids)
if char_bidirect:
eval_inputs.append(char_rev_ids)
eval_inputs.append(char_pos_ids)
#if cap_dim:
# eval_inputs.append(cap_ids)
train_inputs = eval_inputs + [tag_ids]
# Parse optimization method parameters
if "-" in lr_method:
lr_method_name = lr_method[:lr_method.find('-')]
lr_method_parameters = {}
for x in lr_method[lr_method.find('-') + 1:].split('-'):
split = x.split('_')
assert len(split) == 2
lr_method_parameters[split[0]] = float(split[1])
else:
lr_method_name = lr_method
lr_method_parameters = {}
# Compile training function
print 'Compiling...'
if training:
updates = Optimization(clip=5.0).get_updates(
lr_method_name, cost, params, **lr_method_parameters)
f_train = theano.function(inputs=train_inputs,
outputs=cost,
updates=updates,
givens=({
is_train: np.cast['int32'](1)
} if dropout else {}),
on_unused_input='warn')
else:
f_train = None
if plot_cost:
f_plot_cost = theano.function(inputs=train_inputs,
outputs=cost,
givens=({
is_train: np.cast['int32'](1)
} if dropout else {}),
on_unused_input='warn')
else:
f_plot_cost = None
# Compile evaluation function
if tagger != 'crf':
f_eval = theano.function(inputs=eval_inputs,
outputs=tags_scores,
givens=({
is_train: np.cast['int32'](0)
} if dropout else {}),
on_unused_input='warn')
else:
f_eval = theano.function(inputs=eval_inputs,
outputs=forward(
observations,
transitions,
hamming_cost=0,
n_tags=None,
padded_tags_ids=None,
viterbi=True,
return_alpha=False,
return_best_sequence=True),
givens=({
is_train: np.cast['int32'](0)
} if dropout else {}),
on_unused_input='warn')
return f_train, f_eval, f_plot_cost
def build(self, dropout, char_dim, char_lstm_dim, char_bidirect, word_dim,
word_lstm_dim, word_bidirect, pos_dim, pos_lstm_dim, lr_method,
lr_rate, clip_norm, crf, is_train, **kwargs):
"""
建立网络
"""
# 各变量的种类数
n_words = len(self.id_to_word)
n_pos_tags = len(self.id_to_pos)
n_chars = len(self.id_to_char)
n_tags = len(self.id_to_tag)
# 网络变量
self.word_ids = tf.placeholder(
tf.int32, shape=[None, None],
name='word_ids') # 词的数字索引 shape:[batch_size, max_word_len]
self.word_pos_ids = tf.placeholder(
tf.int32, shape=[None],
name='word_pos_ids') # 词的位置索引 shape: [batch_size]
self.pos_ids = tf.placeholder(
tf.int32, shape=[None, None],
name='pos_ids') # 词性标签的数字索引 shape:[batch_size, max_pos_len]
self.char_for_ids = tf.placeholder(
tf.int32, shape=[None, None, None], name='char_for_ids'
) # 字符的前向的数字索引 shape: [batch_size, word_max_len, char_max_len]
self.char_rev_ids = tf.placeholder(
tf.int32, shape=[None, None, None], name='char_rev_ids'
) # 字符的后向的数字索引 shape: [batch_size, word_max_len, char_max_len]
self.char_pos_ids = tf.placeholder(
tf.int32, shape=[None, None], name='char_pos_ids'
) # 字符的位置索引 shape: [batch_size*word_max_len, char_max_len]
self.tag_ids = tf.placeholder(
tf.int32, shape=[None, None],
name='tag_ids') # NER标签的数字索引 shape: [batch_size,word_max_len]
self.tag_id_trans = tf.placeholder(
tf.int32, shape=[None, None, None], name='tag_id_trans'
) # NER标签的转移矩阵的索引 shape: [batch_size,word_max_len+1,2]
self.tag_id_index = tf.placeholder(
tf.int32, shape=[None, None, None],
name='tag_id_index') # shape: [batch_size,word_max_len,2]
# 最终输出 (所有词的特征)
input_dim = 0
inputs = []
#
# 词的输入向量
#
if word_dim:
input_dim += word_dim
with tf.device("/cpu:0"):
word_layer = EmbeddingLayer(n_words,
word_dim,
name='word_layer')
word_input = word_layer.link(self.word_ids)
inputs.append(word_input)
#
# 词性标注的输入向量
#
if pos_dim:
input_dim += pos_dim
with tf.device("/cpu:0"):
pos_layer = EmbeddingLayer(n_pos_tags,
pos_dim,
name='pos_layer')
pos_input = pos_layer.link(self.pos_ids)
inputs.append(pos_input)
#
# 字符的输入向量
#
if char_dim:
input_dim += char_lstm_dim
char_layer = EmbeddingLayer(n_chars, char_dim, name='char_layer')
char_lstm_for = LSTM(char_dim,
char_lstm_dim,
with_batch=True,
name='char_lstm_for')
char_lstm_rev = LSTM(char_dim,
char_lstm_dim,
with_batch=True,
name='char_lstm_rev')
with tf.device("/cpu:0"):
char_for_embedding_batch = char_layer.link(self.char_for_ids)
char_rev_embedding_batch = char_layer.link(self.char_rev_ids)
shape_for = tf.shape(char_for_embedding_batch)
# reshape from [batch_size, word_max_len, char_max_len, char_dim] to [batch_size*word_max_len, char_max_len, char_dim]
char_for_embedding = tf.reshape(
char_for_embedding_batch,
(shape_for[0] * shape_for[1], shape_for[2], shape_for[3]))
shape_rev = tf.shape(char_rev_embedding_batch)
char_rev_embedding = tf.reshape(
char_rev_embedding_batch,
(shape_rev[0] * shape_rev[1], shape_rev[2], shape_rev[3]))
char_lstm_for_states = char_lstm_for.link(char_for_embedding)
char_lstm_rev_states = char_lstm_rev.link(char_rev_embedding)
char_lstm_for_h_trans = tf.transpose(char_lstm_for_states[1],
(1, 0, 2),
name='char_lstm_for_h_trans')
char_lstm_rev_h_trans = tf.transpose(char_lstm_rev_states[1],
(1, 0, 2),
name='char_lstm_rev_h_trans')
char_for_output = tf.gather_nd(char_lstm_for_h_trans,
self.char_pos_ids,
name='char_for_output')
char_rev_output = tf.gather_nd(char_lstm_rev_h_trans,
self.char_pos_ids,
name='char_rev_output')
char_for_output_batch = tf.reshape(
char_for_output, (shape_for[0], shape_for[1], char_lstm_dim))
char_rev_output_batch = tf.reshape(
char_rev_output, (shape_rev[0], shape_rev[1], char_lstm_dim))
inputs.append(char_for_output_batch)
if char_bidirect:
inputs.append(char_rev_output_batch)
input_dim += char_lstm_dim
inputs = tf.concat(inputs, axis=-1)
# 在最终输出上加Dropout层
assert dropout < 1 and 0.0 <= dropout
if dropout:
input_train = tf.nn.dropout(inputs, 1 - dropout)
if is_train:
inputs = input_train
# LSTM for words
word_lstm_for = LSTM(input_dim,
word_lstm_dim,
with_batch=True,
name='word_lstm_for')
word_lstm_rev = LSTM(input_dim,
word_lstm_dim,
with_batch=True,
name='word_lstm_rev')
# 前向隐藏层的输出
word_states_for = word_lstm_for.link(inputs)
word_lstm_for_output = tf.transpose(word_states_for[1], (1, 0, 2),
name='word_lstm_for_h_trans')
# 后向隐藏层的输出
inputs_rev = tf.reverse_sequence(inputs,
self.word_pos_ids,
seq_dim=1,
batch_dim=0)
word_states_rev = word_lstm_rev.link(inputs_rev)
word_lstm_rev_h_trans = tf.transpose(word_states_rev[1], (1, 0, 2),
name='word_lstm_rev_h_trans')
word_lstm_rev_output = tf.reverse_sequence(word_lstm_rev_h_trans,
self.word_pos_ids,
seq_dim=1,
batch_dim=0)
if word_bidirect:
final_output = tf.concat(
[word_lstm_for_output, word_lstm_rev_output], axis=-1)
tanh_layer = HiddenLayer(2 * word_lstm_dim,
word_lstm_dim,
name='tanh_layer',
activation='tanh')
final_output = tanh_layer.link(final_output)
else:
final_output = word_lstm_for_output
final_layer = HiddenLayer(word_lstm_dim, n_tags, name='final_layer')
tags_scores = final_layer.link(final_output)
if not crf:
cross_entropy = tf.nn.sparse_softmax_cross_entropy_with_logits(
labels=self.tag_ids, logits=tags_scores, name='xentropy')
cost = tf.reduce_mean(cross_entropy, name='xentropy_mean')
else:
transitions = shared((n_tags + 2, n_tags + 2), 'transitions')
small = -1000
b_s = np.array([[small] * n_tags + [0, small]]).astype(np.float32)
e_s = np.array([[small] * n_tags + [small, 0]]).astype(np.float32)
# for batch observation
#def recurrence(prev, obs):
# s_len = tf.shape(obs)[0]
# obvs = tf.concat([obs, small * tf.ones((s_len, 2))], axis=1)
# observations = tf.concat([b_s, obvs, e_s], axis=0)
# return observations
#tags_scores_shape = tf.shape(tags_scores)
#obs_initial = tf.ones((tags_scores_shape[1] + 2, n_tags + 2))
#obs_batch = tf.scan(fn=recurrence, elems=tags_scores, initializer=obs_initial)
# 计算标签的分数
def recurrence_real_score(prev, obs):
tags_score = obs[0]
tag_id_index_ = obs[1]
tag_id_trans_ = obs[2]
word_pos_ = obs[3] + 1
tags_score_slice = tags_score[0:word_pos_, :]
tag_id_index_slice = tag_id_index_[0:word_pos_, :]
tag_id_trans_slice = tag_id_trans_[0:(word_pos_ + 1), :]
real_path_score = tf.reduce_sum(
tf.gather_nd(tags_score_slice, tag_id_index_slice))
real_path_score += tf.reduce_sum(
tf.gather_nd(transitions, tag_id_trans_slice))
return tf.reshape(real_path_score, [])
real_path_score_list = tf.scan(fn=recurrence_real_score,
elems=[
tags_scores, self.tag_id_index,
self.tag_id_trans,
self.word_pos_ids
],
initializer=0.0)
def recurrence_all_path(prev, obs):
tags_score = obs[0]
word_pos_ = obs[1] + 1
tags_score_slice = tags_score[0:word_pos_, :]
s_len = tf.shape(tags_score_slice)[0]
obvs = tf.concat(
[tags_score_slice, small * tf.ones((s_len, 2))], axis=1)
observations = tf.concat([b_s, obvs, e_s], axis=0)
all_paths_scores = forward(observations, transitions)
return tf.reshape(all_paths_scores, [])
all_paths_scores_list = tf.scan(
fn=recurrence_all_path,
elems=[tags_scores, self.word_pos_ids],
initializer=0.0)
cost = -tf.reduce_mean(real_path_score_list -
all_paths_scores_list)
# 网络参数
if not crf:
f_score = tf.nn.softmax(tags_scores)
else:
def recurrence_predict(prev, obs):
tags_score = obs[0]
word_pos_ = obs[1] + 1
tags_score_slice = tags_score[0:word_pos_, :]
s_len = tf.shape(tags_score_slice)[0]
obvs = tf.concat(
[tags_score_slice, small * tf.ones((s_len, 2))], axis=1)
observations = tf.concat([b_s, obvs, e_s], axis=0)
all_paths_scores = forward(observations,
transitions,
viterbi=True,
return_alpha=False,
return_best_sequence=True)
all_paths_scores = tf.concat([
all_paths_scores,
tf.zeros([tf.shape(tags_score)[0] - s_len], tf.int32)
],
axis=0)
return all_paths_scores
f_score = tf.scan(fn=recurrence_predict,
elems=[tags_scores, self.word_pos_ids],
initializer=tf.zeros(
[tf.shape(tags_scores)[1] + 2], tf.int32))
# 选择优化方法
tvars = tf.trainable_variables()
grads = tf.gradients(cost, tvars)
if clip_norm > 0:
grads, _ = tf.clip_by_global_norm(grads, clip_norm)
if lr_method == 'sgd':
optimizer = tf.train.GradientDescentOptimizer(lr_rate)
elif lr_method == 'adagrad':
optimizer = tf.train.AdagradOptimizer(lr_rate)
elif lr_method == 'adadelta':
optimizer = tf.train.AdadeltaOptimizer(lr_rate)
elif lr_method == 'adam':
optimizer = tf.train.AdamOptimizer(lr_rate)
elif lr_method == 'rmsprop':
optimizer = tf.train.RMSPropOptimizer(lr_rate)
else:
raise ("Not implemented learning method: %s" % lr_method)
train_op = optimizer.apply_gradients(zip(grads, tvars))
# Tensorboard可视化cost的趋势
tf.summary.scalar('loss', cost)
return cost, f_score, train_op
def build(self,
dropout,
char_dim,
char_hidden_dim,
char_bidirect,
layer2_hidden_dim,
lr_method,
layer2,
batch_size,
pre_emb,
use_gaze,
crf,
training=True,
**kwargs):
"""
Build the network.
"""
# Training parameters
n_chars = len(self.id_to_char)
n_tags = len(self.id_to_tag)
# Network variables
is_train = T.iscalar('is_train') # declare variable,声明整型变量is_train
char_ids = T.ivector(name='char_ids') #声明整型一维向量
if use_gaze:
gaze = T.imatrix(name='gaze')
#hamming_cost = T.matrix('hamming_cost', theano.config.floatX) # 声明整型二维矩阵
# tag_ids = T.imatrix(name='tag_ids')
tag_ids = T.ivector(name='tag_ids')
# Sentence length
s_len = char_ids.shape[0] #每个句子中的字数
# Final input (all word features)
#
# Char inputs
#
if char_dim:
char_layer = EmbeddingLayer(n_chars, char_dim, name='char_layer')
char_input = char_layer.link(char_ids)
# Initialize with pretrained embeddings
if pre_emb and training:
new_weights = char_layer.embeddings.get_value()
print 'Loading pretrained embeddings from %s...' % pre_emb
pretrained = {}
emb_invalid = 0
for i, line in enumerate(
codecs.open(pre_emb, 'r', 'utf-8', 'ignore')):
line = line.rstrip().split()
if len(line) == char_dim + 1:
pretrained[line[0]] = np.array(
[float(x) for x in line[1:]]).astype(np.float32)
else:
emb_invalid += 1
if emb_invalid > 0:
print 'WARNING: %i invalid lines' % emb_invalid
c_found = 0
c_lower = 0
c_zeros = 0
# Lookup table initialization
for i in xrange(n_chars):
char = self.id_to_char[i]
if char in pretrained:
new_weights[i] = pretrained[char]
c_found += 1
elif char.lower() in pretrained:
new_weights[i] = pretrained[char.lower()]
c_lower += 1
elif re.sub('\d', '0', char) in pretrained:
new_weights[i] = pretrained[re.sub('\d', '0', char)]
c_zeros += 1
char_layer.embeddings.set_value(new_weights)
print 'Loaded %i pretrained embeddings.' % len(pretrained)
print(
'%i / %i (%.4f%%) chars have been initialized with '
'pretrained embeddings.') % (
c_found + c_lower + c_zeros, n_chars, 100. *
(c_found + c_lower + c_zeros) / n_chars)
print('%i found directly, %i after lower, %i after zero.') % (
c_found, c_lower, c_zeros)
#
# Dropout on final input
#
if dropout:
dropout_layer = DropoutLayer(p=dropout)
input_train = dropout_layer.link(char_input)
input_test = (1 - dropout) * char_input
char_input = T.switch(T.neq(is_train, 0), input_train,
input_test) # 条件句
# LSTM for chars, first layer
char_lstm_for1 = LSTM(char_dim,
char_hidden_dim,
with_batch=False,
name='first_char_lstm_for')
char_lstm_rev1 = LSTM(char_dim,
char_hidden_dim,
with_batch=False,
name='first_char_lstm_rev')
char_lstm_for1.link(char_input) # char的顺序： l i k e
char_lstm_rev1.link(char_input[::-1, :]) # 单词的顺序： e k i l
char_for_output1 = char_lstm_for1.h
char_rev_output1 = char_lstm_rev1.h[::-1, :]
if char_bidirect:
final_output = T.concatenate([char_for_output1, char_rev_output1],
axis=1)
tanh_layer1 = HiddenLayer(2 * char_hidden_dim,
char_hidden_dim,
name='tanh_layer1',
activation='tanh')
final_output = tanh_layer1.link(final_output)
else:
final_output = char_for_output1
if layer2:
#
# Dropout on final input
#
if dropout:
dropout_layer = DropoutLayer(p=dropout)
input_train = dropout_layer.link(final_output)
input_test = (1 - dropout) * final_output
final_output = T.switch(T.neq(is_train, 0), input_train,
input_test) # 条件句
# LSTM for chars, second layer
char_lstm_for2 = LSTM(char_hidden_dim,
layer2_hidden_dim,
with_batch=False,
name='second_char_lstm_for')
char_lstm_rev2 = LSTM(char_hidden_dim,
layer2_hidden_dim,
with_batch=False,
name='second_char_lstm_rev')
char_lstm_for2.link(final_output)
char_lstm_rev2.link(final_output[::-1, :])
char_for_output2 = char_lstm_for2.h
char_rev_output2 = char_lstm_rev2.h[::-1, :]
if char_bidirect:
final_output = T.concatenate(
[char_for_output2, char_rev_output2], axis=1)
tanh_layer2 = HiddenLayer(2 * layer2_hidden_dim,
layer2_hidden_dim,
name='tanh_layer2',
activation='tanh')
final_output = tanh_layer2.link(final_output)
else:
final_output = char_for_output2
if layer2:
dims = layer2_hidden_dim
else:
dims = char_hidden_dim
if use_gaze:
final_output = T.concatenate([final_output, gaze], axis=1)
dims = dims + n_tags
# final_output = T.reshape(final_output, (-1, input_dim))
# Sentence to Named Entity tags - Score，ci与CRF之间的隐含层
final_layer = HiddenLayer(dims,
n_tags,
name='final_layer',
activation=(None if crf else 'softmax'))
tags_scores = final_layer.link(final_output)
# No CRF
if not crf:
cost = T.nnet.categorical_crossentropy(tags_scores, tag_ids).mean()
# CRF
else:
transitions = shared((n_tags + 2, n_tags + 2), 'transitions')
small = -1000
b_s = np.array([[small] * n_tags + [0, small]]).astype(np.float32)
e_s = np.array([[small] * n_tags + [small, 0]]).astype(np.float32)
observations = T.concatenate(
[tags_scores, small * T.ones((s_len, 2))], axis=1)
observations = T.concatenate([b_s, observations, e_s], axis=0)
# Score from tags
real_path_score = tags_scores[T.arange(s_len),
tag_ids].sum() # P中对应元素的求和好
# Score from add_componentnsitions
b_id = theano.shared(value=np.array([n_tags], dtype=np.int32))
e_id = theano.shared(value=np.array([n_tags + 1], dtype=np.int32))
padded_tags_ids = T.concatenate([b_id, tag_ids, e_id], axis=0)
real_path_score += transitions[
padded_tags_ids[T.arange(s_len + 1)],
padded_tags_ids[T.arange(s_len + 1) + 1]].sum() # A中对应元素的求和
all_paths_scores = forward(observations, transitions)
cost = -(real_path_score - all_paths_scores)
# Network parameters
params = []
if char_dim:
self.add_component(char_layer)
params.extend(char_layer.params)
self.add_component(char_lstm_for1)
params.extend(char_lstm_for1.params)
if char_bidirect:
self.add_component(char_lstm_rev1)
params.extend(char_lstm_rev1.params)
self.add_component(tanh_layer1)
params.extend(tanh_layer1.params)
if layer2:
self.add_component(char_lstm_for2)
params.extend(char_lstm_for2.params)
if char_bidirect:
self.add_component(char_lstm_rev2)
params.extend(char_lstm_rev2.params)
self.add_component(tanh_layer2)
params.extend(tanh_layer2.params)
self.add_component(final_layer)
params.extend(final_layer.params)
if crf:
self.add_component(transitions)
params.append(transitions)
# Prepare train and eval inputs
eval_inputs = []
if char_dim:
eval_inputs.append(char_ids)
if use_gaze:
eval_inputs.append(gaze)
train_inputs = eval_inputs + [tag_ids]
# Parse optimization method parameters
if "-" in lr_method:
lr_method_name = lr_method[:lr_method.find('-')]
lr_method_parameters = {}
for x in lr_method[lr_method.find('-') + 1:].split('-'):
split = x.split('_')
assert len(split) == 2
lr_method_parameters[split[0]] = float(split[1])
else:
lr_method_name = lr_method
lr_method_parameters = {}
# Compile training function
print 'Compiling...'
if training:
updates = Optimization(clip=5.0).get_updates(
lr_method_name, cost, params, **lr_method_parameters)
f_train = theano.function(inputs=train_inputs,
outputs=cost,
updates=updates,
givens=({
is_train: np.cast['int32'](1)
} if dropout else {}))
else:
f_train = None
# Compile evaluation function
if not crf:
f_eval = theano.function(inputs=eval_inputs,
outputs=tags_scores,
givens=({
is_train: np.cast['int32'](0)
} if dropout else {}))
else:
f_eval = theano.function(inputs=eval_inputs,
outputs=forward(
observations,
transitions,
viterbi=True,
return_alpha=False,
return_best_sequence=True),
givens=({
is_train: np.cast['int32'](0)
} if dropout else {}))
return f_train, f_eval
def build(self,
dropout,
char_dim,
char_lstm_dim,
char_bidirect,
word_dim,
word_lstm_dim,
word_bidirect,
lr_method,
pre_emb,
crf,
cap_dim,
training=True,
**kwargs
):
"""
Build the network.
"""
# Training parameters
n_words = len(self.id_to_word)
n_chars = len(self.id_to_char)
n_tags = len(self.id_to_tag)
# Number of capitalization features
if cap_dim:
n_cap = 4
# Network variables
is_train = T.iscalar('is_train')
word_ids = T.ivector(name='word_ids')
char_for_ids = T.imatrix(name='char_for_ids')
char_rev_ids = T.imatrix(name='char_rev_ids')
char_pos_ids = T.ivector(name='char_pos_ids')
tag_ids = T.ivector(name='tag_ids')
cap_ids = T.ivector(name='cap_ids')
# Sentence length
# Final input (all word features)
input_dim = 0
inputs = []
s_len = (char_pos_ids).shape[0]
#
#
# Chars inputs
#
input_dim += (char_lstm_dim * 2)
char_layer = EmbeddingLayer(n_chars, char_dim, name='char_layer')
char_lstm_for = LSTM(char_dim, char_lstm_dim, with_batch=False,
name='char_lstm_for')
char_lstm_rev = LSTM(char_dim, char_lstm_dim, with_batch=False,
name='char_lstm_rev')
char_lstm_for.link(char_layer.link(word_ids))
char_lstm_rev.link(char_layer.link(cap_ids))
final_layer = HiddenLayer(char_lstm_dim, n_chars, name='final_char_layer',
activation=('softmax'))
chars_final = final_layer.link(char_lstm_for.h)
final_rev_layer = HiddenLayer(char_lstm_dim, n_chars, name='final_char_rev_layer',
activation=('softmax'))
chars_rev_final = final_layer.link(char_lstm_rev.h)
cost_chars = T.nnet.categorical_crossentropy(chars_final, char_pos_ids).mean()
cost_chars_rev = T.nnet.categorical_crossentropy(chars_rev_final, tag_ids).mean()
# Network parameters
params = []
if char_dim:
self.add_component(char_layer)
self.add_component(char_lstm_for)
params.extend(char_layer.params)
params.extend(char_lstm_for.params)
self.add_component(char_lstm_rev)
params.extend(char_lstm_rev.params)
# Prepare train and eval inputs
eval_inputs = []
if word_dim:
eval_inputs.append(word_ids)
if char_dim:
eval_inputs.append(char_for_ids)
if char_bidirect:
eval_inputs.append(char_rev_ids)
eval_inputs.append(char_pos_ids)
#if cap_dim:
eval_inputs.append(tag_ids)
eval_inputs.append(cap_ids)
# Parse optimization method parameters
if "-" in lr_method:
lr_method_name = lr_method[:lr_method.find('-')]
lr_method_parameters = {}
for x in lr_method[lr_method.find('-') + 1:].split('-'):
split = x.split('_')
assert len(split) == 2
lr_method_parameters[split[0]] = float(split[1])
else:
lr_method_name = lr_method
lr_method_parameters = {}
# Fetch gradients from both char_lstms
gradients = T.grad(cost_chars, char_lstm_for.params)
gradients_rev = T.grad(cost_chars_rev, char_lstm_rev.params)
# Return forward char_lstm grads
f_eval = theano.function(
inputs=eval_inputs,
outputs=gradients,
givens=({is_train: np.cast['int32'](0)} if dropout else {}), on_unused_input='ignore'
)
# Return reverse char_lstm grads
f_eval_rev = theano.function(
inputs=eval_inputs,
outputs=gradients_rev,
givens=({is_train: np.cast['int32'](0)} if dropout else {}), on_unused_input='ignore'
)
return f_eval, f_eval_rev
def build(self,
dropout,
char_dim,
char_lstm_dim,
char_bidirect,
word_dim,
word_lstm_dim,
word_bidirect,
lr_method,
pre_emb,
crf,
cap_dim,
training=True,
word_to_id=None,
**kwargs):
"""
Build the network.
"""
# Training parameters
n_words = len(self.id_to_word)
n_chars = len(self.id_to_char)
n_tags = len(self.id_to_tag)
# Number of capitalization features
if cap_dim:
n_cap = 6
if self.parameters['pos_dim']:
n_pos = len(self.id_to_pos)
if self.parameters['ortho_dim']:
n_ortho = len(self.id_to_ortho)
if self.parameters['multi_task']:
n_segment_tags = len(self.id_to_segment)
if self.parameters['pre_emb_1_dim']:
n_words_1 = len(self.id_to_word_1)
# Network variables
is_train = T.iscalar('is_train')
word_ids = T.ivector(name='word_ids')
char_for_ids = T.imatrix(name='char_for_ids')
char_rev_ids = T.imatrix(name='char_rev_ids')
char_pos_ids = T.ivector(name='char_pos_ids')
tag_ids = T.ivector(name='tag_ids')
if cap_dim:
cap_ids = T.ivector(name='cap_ids')
if self.parameters['pos_dim']:
pos_ids = T.ivector(name='pos_ids')
if self.parameters['ortho_dim']:
ortho_ids = T.ivector(name='ortho_ids')
if self.parameters['multi_task']:
segment_tags_ids = T.ivector(name='segment_tags_ids')
if self.parameters['pre_emb_1_dim']:
word_ids_1 = T.ivector(name='doc_ids_dn')
if self.parameters['language_model']:
y_fwd_ids = T.ivector(name='y_fwd_ids')
y_bwd_ids = T.ivector(name='y_bwd_ids')
# Sentence length
s_len = (word_ids if word_dim else char_pos_ids).shape[0]
# Final input (all word features)
input_dim = 0
inputs = []
#
# Word inputs
#
if word_dim:
input_dim += word_dim
print('word_dim: {}'.format(word_dim))
word_layer = EmbeddingLayer(n_words, word_dim, name='word_layer')
word_input = word_layer.link(word_ids)
inputs.append(word_input)
# Initialize with pretrained embeddings
if pre_emb and training and not self.parameters['reload']:
new_weights = word_layer.embeddings.get_value()
print(
'Loading pretrained embeddings from {}...'.format(pre_emb))
pretrained = {}
emb_invalid = 0
for i, line in enumerate(codecs.open(pre_emb, 'r', 'utf-8')):
line = line.rstrip().split()
if len(line) == word_dim + 1:
pretrained[line[0]] = np.array(
[float(x) for x in line[1:]]).astype(np.float32)
else:
emb_invalid += 1
if emb_invalid > 0:
print('WARNING: {} invalid lines'.format(emb_invalid))
c_found = 0
c_lower = 0
c_zeros = 0
oov_words = 0
if self.parameters['emb_of_unk_words']:
# TODO
# add path as a parameter
fast_text_model_p = '/home/ubuntu/usama_ws/resources/Spanish-Corporas/embeddings/fasttext/' \
'fasttext-100d.bin'
ft_model = load_model(fast_text_model_p)
# Lookup table initialization
for i in range(n_words):
word = self.id_to_word[i]
if word in pretrained:
new_weights[i] = pretrained[word]
c_found += 1
elif word.lower() in pretrained:
new_weights[i] = pretrained[word.lower()]
c_lower += 1
elif re.sub('\d', '0', word.lower()) in pretrained:
new_weights[i] = pretrained[re.sub(
'\d', '0', word.lower())]
c_zeros += 1
else:
if self.parameters['emb_of_unk_words']:
new_weights[i] = ft_model.get_word_vector(word)
oov_words += 1
# set row corresponding to padding token to 0
new_weights[word_to_id['<PADDING>']] = np.zeros(word_dim)
word_layer.embeddings.set_value(new_weights)
print('Loaded {} pretrained embeddings.'.format(
len(pretrained)))
print('{} / {} ({} percent) words have been initialized with '
'pretrained embeddings.'.format(
c_found + c_lower + c_zeros, n_words,
100. * (c_found + c_lower + c_zeros) / n_words))
print('{} found directly, {} after lowercasing, '
'{} after lowercasing + zero.'.format(
c_found, c_lower, c_zeros))
print('oov words count: {}'.format(oov_words))
#
# Word inputs
#
if self.parameters['pre_emb_1']:
print('pre_emb_1_dim: {}'.format(self.parameters['pre_emb_1_dim']))
input_dim += self.parameters['pre_emb_1_dim']
word_layer_1 = EmbeddingLayer(n_words_1,
word_dim,
name='word_layer_1')
word_input_1 = word_layer_1.link(word_ids_1)
inputs.append(word_input_1)
if training and not self.parameters['reload']:
# Initialize with pretrained embeddings
new_weights_1 = word_layer_1.embeddings.get_value()
print('Loading pretrained embeddings from {}...'.format(
self.parameters['pre_emb_1']))
pretrained_1 = {}
emb_invalid_1 = 0
for i, line in enumerate(
codecs.open(self.parameters['pre_emb_1'], 'r',
'utf-8')):
line = line.rstrip().split()
if len(line) == self.parameters['pre_emb_1_dim'] + 1:
pretrained_1[line[0]] = np.array(
[float(x) for x in line[1:]]).astype(np.float32)
else:
emb_invalid_1 += 1
if emb_invalid_1 > 0:
print('WARNING: {} invalid lines'.format(emb_invalid_1))
c_found = 0
c_lower = 0
c_zeros = 0
oov_words = 0
# Lookup table initialization
for i in range(n_words_1):
word_1 = self.id_to_word_1[i]
if word_1 in pretrained_1:
new_weights_1[i] = pretrained_1[word_1]
c_found += 1
elif word_1.lower() in pretrained_1:
new_weights_1[i] = pretrained_1[word_1.lower()]
c_lower += 1
elif re.sub('\d', '0', word_1.lower()) in pretrained_1:
new_weights_1[i] = pretrained_1[re.sub(
'\d', '0', word_1.lower())]
c_zeros += 1
else:
oov_words += 1
word_layer_1.embeddings.set_value(new_weights_1)
print('Loaded {} pretrained embeddings.'.format(
len(pretrained_1)))
print('{} / {} ({} percent) words have been initialized with '
'pretrained embeddings.'.format(
c_found + c_lower + c_zeros, n_words,
100. * (c_found + c_lower + c_zeros) / n_words))
print('{} found directly, {} after lowercasing, '
'{} after lowercasing + zero.'.format(
c_found, c_lower, c_zeros))
print('oov words count: {}'.format(oov_words))
#
# Chars inputs
#
if char_dim:
input_dim += char_lstm_dim
char_layer = EmbeddingLayer(n_chars, char_dim, name='char_layer')
char_lstm_for = LSTM(char_dim,
char_lstm_dim,
with_batch=True,
name='char_lstm_for')
char_lstm_rev = LSTM(char_dim,
char_lstm_dim,
with_batch=True,
name='char_lstm_rev')
char_lstm_for.link(char_layer.link(char_for_ids))
char_lstm_rev.link(char_layer.link(char_rev_ids))
char_for_output = char_lstm_for.h.dimshuffle(
(1, 0, 2))[T.arange(s_len), char_pos_ids]
char_rev_output = char_lstm_rev.h.dimshuffle(
(1, 0, 2))[T.arange(s_len), char_pos_ids]
inputs.append(char_for_output)
if char_bidirect:
inputs.append(char_rev_output)
input_dim += char_lstm_dim
#
# Capitalization feature
#
if cap_dim:
input_dim += cap_dim
cap_layer = EmbeddingLayer(n_cap, cap_dim, name='cap_layer')
inputs.append(cap_layer.link(cap_ids))
if self.parameters['pos_dim']:
input_dim += self.parameters['pos_dim']
pos_layer = EmbeddingLayer(n_pos,
self.parameters['pos_dim'],
name='pos_layer')
inputs.append(pos_layer.link(pos_ids))
# zeroing the '<UNK>' pos tag row
# loading reverse mappings
pos_to_id = {y: x for x, y in self.id_to_pos.items()}
unk_idx = pos_to_id['<UNK>']
_pos_wts = pos_layer.embeddings.get_value()
_pos_wts[unk_idx] = [0.] * self.parameters['pos_dim']
pos_layer.embeddings.set_value(_pos_wts)
if self.parameters['ortho_dim']:
input_dim += self.parameters['ortho_dim']
ortho_layer = EmbeddingLayer(n_ortho,
self.parameters['ortho_dim'],
name='ortho_layer')
inputs.append(ortho_layer.link(ortho_ids))
ortho_to_id = {y: x for x, y in self.id_to_ortho.items()}
unk_idx = ortho_to_id['<UNK>']
_pos_wts = ortho_layer.embeddings.get_value()
_pos_wts[unk_idx] = [0.] * self.parameters['ortho_dim']
ortho_layer.embeddings.set_value(_pos_wts)
print('input_dim: {}'.format(input_dim))
# Prepare final input
inputs = T.concatenate(inputs,
axis=1) if len(inputs) != 1 else inputs[0]
#
# Dropout on final input
#
if dropout:
dropout_layer = DropoutLayer(p=dropout)
input_train = dropout_layer.link(inputs)
input_test = (1 - dropout) * inputs
inputs = T.switch(T.neq(is_train, 0), input_train, input_test)
# LSTM for words
word_lstm_for = LSTM(input_dim,
word_lstm_dim,
with_batch=False,
name='word_lstm_for')
word_lstm_rev = LSTM(input_dim,
word_lstm_dim,
with_batch=False,
name='word_lstm_rev')
word_lstm_for.link(inputs)
word_lstm_rev.link(inputs[::-1, :])
word_for_output = word_lstm_for.h
word_rev_output = word_lstm_rev.h[::-1, :]
if word_bidirect:
n_h = 2 * word_lstm_dim
final_output = T.concatenate([word_for_output, word_rev_output],
axis=1)
tanh_layer = HiddenLayer(n_h,
word_lstm_dim,
name='tanh_layer',
activation='tanh')
final_output = tanh_layer.link(final_output)
else:
final_output = word_for_output
# Sentence to Named Entity tags - Score
final_layer = HiddenLayer(word_lstm_dim,
n_tags,
name='final_layer',
activation=(None if crf else 'softmax'))
tags_scores = final_layer.link(final_output)
if self.parameters['multi_task']:
# Sentence to Named Entity Segmentation tags - Score
segment_layer = HiddenLayer(
word_lstm_dim,
n_segment_tags,
name='segment_layer',
activation=(None if crf else 'softmax'))
segment_tags_scores = segment_layer.link(final_output)
# No CRF
if not crf:
cost = T.nnet.categorical_crossentropy(tags_scores, tag_ids).mean()
if self.parameters['multi_task']:
cost_segment = T.nnet.categorical_crossentropy(
segment_tags_scores, segment_tags_ids).mean()
cost += cost_segment
# CRF
else:
transitions = shared((n_tags + 2, n_tags + 2), 'transitions')
small = -1000
b_s = np.array([[small] * n_tags + [0, small]]).astype(np.float32)
e_s = np.array([[small] * n_tags + [small, 0]]).astype(np.float32)
observations = T.concatenate(
[tags_scores, small * T.ones((s_len, 2))], axis=1)
observations = T.concatenate([b_s, observations, e_s], axis=0)
# Score from tags
real_path_score = tags_scores[T.arange(s_len), tag_ids].sum()
# Score from transitions
b_id = theano.shared(value=np.array([n_tags], dtype=np.int32))
e_id = theano.shared(value=np.array([n_tags + 1], dtype=np.int32))
padded_tags_ids = T.concatenate([b_id, tag_ids, e_id], axis=0)
real_path_score += transitions[padded_tags_ids[T.arange(s_len +
1)],
padded_tags_ids[T.arange(s_len + 1)
+ 1]].sum()
all_paths_scores = forward(observations, transitions)
cost = -(real_path_score - all_paths_scores)
if self.parameters['multi_task']:
segment_transitions = shared(
(n_segment_tags + 2, n_segment_tags + 2),
'segment_transitions')
seg_small = -1000
seg_b_s = np.array([[seg_small] * n_segment_tags +
[0, seg_small]]).astype(np.float32)
seg_e_s = np.array([[seg_small] * n_segment_tags +
[seg_small, 0]]).astype(np.float32)
segment_observations = T.concatenate(
[segment_tags_scores, seg_small * T.ones((s_len, 2))],
axis=1)
segment_observations = T.concatenate(
[seg_b_s, segment_observations, seg_e_s], axis=0)
# Score from tags
seg_real_path_score = segment_tags_scores[
T.arange(s_len), segment_tags_ids].sum()
# Score from transitions
seg_b_id = theano.shared(
value=np.array([n_segment_tags], dtype=np.int32))
seg_e_id = theano.shared(
value=np.array([n_segment_tags + 1], dtype=np.int32))
seg_padded_tags_ids = T.concatenate(
[seg_b_id, segment_tags_ids, seg_e_id], axis=0)
seg_real_path_score += segment_transitions[
seg_padded_tags_ids[T.arange(s_len + 1)],
seg_padded_tags_ids[T.arange(s_len + 1) + 1]].sum()
seg_all_paths_scores = forward(segment_observations,
segment_transitions)
cost_segment = -(seg_real_path_score - seg_all_paths_scores)
cost += cost_segment
if training and self.parameters['ranking_loss']:
def recurrence(x_t, y_t):
token_prob_pos = x_t[y_t]
arg_max_1 = T.argmax(x_t)
arg_max_2 = T.argsort(-x_t)[1]
token_prob_neg = ifelse(T.eq(y_t, arg_max_1), x_t[arg_max_2],
x_t[arg_max_1])
cost_t = T.max([0, 1.0 - token_prob_pos + token_prob_neg])
return cost_t
cost_r, _ = theano.scan(recurrence,
sequences=[tags_scores, tag_ids])
cum_cost = T.sum(cost_r)
cost += cum_cost
if self.parameters['language_model']:
lm_fwd_layer = HiddenLayer(word_lstm_dim,
n_words,
name='lm_fwd_layer',
activation='softmax')
lm_fwd_scores = lm_fwd_layer.link(final_output)
lm_fwd_cost = T.nnet.categorical_crossentropy(
lm_fwd_scores, y_fwd_ids).mean()
lm_bwd_layer = HiddenLayer(word_lstm_dim,
n_words,
name='lm_bwd_layer',
activation='softmax')
lm_bwd_scores = lm_bwd_layer.link(final_output)
lm_bwd_cost = T.nnet.categorical_crossentropy(
lm_bwd_scores, y_bwd_ids).mean()
cost_lm = lm_fwd_cost + lm_bwd_cost
cost += cost_lm
# Network parameters
params = []
if word_dim:
self.add_component(word_layer)
params.extend(word_layer.params)
if self.parameters['pre_emb_1']:
self.add_component(word_layer_1)
params.extend(word_layer_1.params)
if char_dim:
self.add_component(char_layer)
self.add_component(char_lstm_for)
params.extend(char_layer.params)
params.extend(char_lstm_for.params)
if char_bidirect:
self.add_component(char_lstm_rev)
params.extend(char_lstm_rev.params)
self.add_component(word_lstm_for)
params.extend(word_lstm_for.params)
if word_bidirect:
self.add_component(word_lstm_rev)
params.extend(word_lstm_rev.params)
if cap_dim:
self.add_component(cap_layer)
params.extend(cap_layer.params)
if self.parameters['pos_dim']:
self.add_component(pos_layer)
params.extend(pos_layer.params)
if self.parameters['ortho_dim']:
self.add_component(ortho_layer)
params.extend(ortho_layer.params)
self.add_component(final_layer)
params.extend(final_layer.params)
if self.parameters['multi_task']:
self.add_component(segment_layer)
params.extend(segment_layer.params)
if crf:
self.add_component(transitions)
params.append(transitions)
if self.parameters['multi_task']:
self.add_component(segment_transitions)
params.append(segment_transitions)
if word_bidirect:
self.add_component(tanh_layer)
params.extend(tanh_layer.params)
if self.parameters['language_model']:
self.add_component(lm_fwd_layer)
params.extend(lm_fwd_layer.params)
self.add_component(lm_bwd_layer)
params.extend(lm_bwd_layer.params)
# Prepare train and eval inputs
eval_inputs = []
if word_dim:
eval_inputs.append(word_ids)
if char_dim:
eval_inputs.append(char_for_ids)
if char_bidirect:
eval_inputs.append(char_rev_ids)
eval_inputs.append(char_pos_ids)
if cap_dim:
eval_inputs.append(cap_ids)
if self.parameters['pos_dim']:
eval_inputs.append(pos_ids)
if self.parameters['ortho_dim']:
eval_inputs.append(ortho_ids)
if self.parameters['pre_emb_1']:
eval_inputs.append(word_ids_1)
train_inputs = eval_inputs + [tag_ids]
if self.parameters['multi_task']:
train_inputs += [segment_tags_ids]
if self.parameters['language_model']:
train_inputs.append(y_fwd_ids)
train_inputs.append(y_bwd_ids)
# Parse optimization method parameters
if "-" in lr_method:
lr_method_name = lr_method[:lr_method.find('-')]
lr_method_parameters = {}
for x in lr_method[lr_method.find('-') + 1:].split('-'):
split = x.split('_')
assert len(split) == 2
lr_method_parameters[split[0]] = float(split[1])
else:
lr_method_name = lr_method
lr_method_parameters = {}
# Compile training function
print('Compiling...')
if training:
updates = Optimization(clip=5.0).get_updates(
lr_method_name, cost, params, **lr_method_parameters)
f_train = theano.function(inputs=train_inputs,
outputs=cost,
updates=updates,
givens=({
is_train: np.cast['int32'](1)
} if dropout else {}),
allow_input_downcast=True)
else:
f_train = None
# Compile evaluation function
if not crf:
f_eval = theano.function(inputs=eval_inputs,
outputs=tags_scores,
givens=({
is_train: np.cast['int32'](0)
} if dropout else {}),
allow_input_downcast=True)
else:
f_eval = theano.function(inputs=eval_inputs,
outputs=forward(
observations,
transitions,
viterbi=True,
return_alpha=False,
return_best_sequence=True),
givens=({
is_train: np.cast['int32'](0)
} if dropout else {}),
allow_input_downcast=True)
return f_train, f_eval
def build(self,
dropout,
char_dim,
char_lstm_dim,
char_bidirect,
word_dim,
word_lstm_dim,
word_bidirect,
lr_method,
pre_emb,
crf,
cap_dim,
training=True,
**kwargs):
"""
Build the network.
"""
# Training parameters
n_words = len(self.id_to_word)
n_chars = len(self.id_to_char)
n_tags = len(self.id_to_tag)
# Number of capitalization features
if cap_dim:
n_cap = 4
# Network variables
is_train = T.iscalar('is_train')
word_ids = T.ivector(name='word_ids')
char_for_ids = T.imatrix(name='char_for_ids')
char_rev_ids = T.imatrix(name='char_rev_ids')
char_pos_ids = T.ivector(name='char_pos_ids')
tag_ids = T.ivector(name='tag_ids')
cap_ids = T.ivector(name='cap_ids')
# Sentence length
# Final input (all word features)
input_dim = 0
inputs = []
s_len = (char_pos_ids).shape[0]
#
#
# Chars inputs
#
input_dim += (char_lstm_dim * 2)
char_layer = EmbeddingLayer(n_chars, char_dim, name='char_layer')
char_lstm_for = LSTM(char_dim,
char_lstm_dim,
with_batch=False,
name='char_lstm_for')
char_lstm_rev = LSTM(char_dim,
char_lstm_dim,
with_batch=False,
name='char_lstm_rev')
char_lstm_for.link(char_layer.link(word_ids))
char_lstm_rev.link(char_layer.link(cap_ids))
final_layer = HiddenLayer(char_lstm_dim,
n_chars,
name='final_char_layer',
activation=('softmax'))
chars_final = final_layer.link(char_lstm_for.h)
final_rev_layer = HiddenLayer(char_lstm_dim,
n_chars,
name='final_char_rev_layer',
activation=('softmax'))
chars_rev_final = final_layer.link(char_lstm_rev.h)
cost_chars = T.nnet.categorical_crossentropy(chars_final,
char_pos_ids).mean()
cost_chars_rev = T.nnet.categorical_crossentropy(
chars_rev_final, tag_ids).mean()
# Network parameters
params = []
if char_dim:
self.add_component(char_layer)
self.add_component(char_lstm_for)
params.extend(char_layer.params)
params.extend(char_lstm_for.params)
self.add_component(char_lstm_rev)
params.extend(char_lstm_rev.params)
# Prepare train and eval inputs
eval_inputs = []
if word_dim:
eval_inputs.append(word_ids)
if char_dim:
eval_inputs.append(char_for_ids)
if char_bidirect:
eval_inputs.append(char_rev_ids)
eval_inputs.append(char_pos_ids)
#if cap_dim:
eval_inputs.append(tag_ids)
eval_inputs.append(cap_ids)
# Parse optimization method parameters
if "-" in lr_method:
lr_method_name = lr_method[:lr_method.find('-')]
lr_method_parameters = {}
for x in lr_method[lr_method.find('-') + 1:].split('-'):
split = x.split('_')
assert len(split) == 2
lr_method_parameters[split[0]] = float(split[1])
else:
lr_method_name = lr_method
lr_method_parameters = {}
# Fetch gradients from both char_lstms
gradients = T.grad(cost_chars, char_lstm_for.params)
gradients_rev = T.grad(cost_chars_rev, char_lstm_rev.params)
# Return forward char_lstm grads
f_eval = theano.function(inputs=eval_inputs,
outputs=gradients,
givens=({
is_train: np.cast['int32'](0)
} if dropout else {}),
on_unused_input='ignore')
# Return reverse char_lstm grads
f_eval_rev = theano.function(inputs=eval_inputs,
outputs=gradients_rev,
givens=({
is_train: np.cast['int32'](0)
} if dropout else {}),
on_unused_input='ignore')
return f_eval, f_eval_rev
def build(self,
dropout,
char_dim,
char_lstm_dim,
char_bidirect,
word_dim,
word_lstm_dim,
word_bidirect,
lr_method,
pre_emb,
crf,
cap_dim,
training=True,
**kwargs
):
"""
Build the network.
"""
# Training parameters
n_words = len(self.id_to_word)
n_chars = len(self.id_to_char)
n_tags_loaded = len(self.id_to_tag_old)
n_tags = len(self.id_to_tag)
print "n_words: ", n_words, "n_chars: ", n_chars, "n_tags_loaded: ", n_tags_loaded, "n_tags(new ones): ", n_tags
print self.id_to_tag
print self.id_to_tag_old
# Number of capitalization features
if cap_dim:
n_cap = 4
# Network variables
is_train = T.iscalar('is_train')
word_ids = T.ivector(name='word_ids')
char_for_ids = T.imatrix(name='char_for_ids')
char_rev_ids = T.imatrix(name='char_rev_ids')
char_pos_ids = T.ivector(name='char_pos_ids')
tag_ids = T.ivector(name='tag_ids')
if cap_dim:
cap_ids = T.ivector(name='cap_ids')
# Sentence length
s_len = (word_ids if word_dim else char_pos_ids).shape[0]
# Final input (all word features)
input_dim = 0
inputs = []
#
# Word inputs
#
if word_dim:
input_dim += word_dim
word_layer = EmbeddingLayer(n_words, word_dim, name='word_layer')
word_input = word_layer.link(word_ids)
inputs.append(word_input)
#
# Chars inputs
#
if char_dim:
input_dim += char_lstm_dim
char_layer = EmbeddingLayer(n_chars, char_dim, name='char_layer')
char_lstm_for = LSTM(char_dim, char_lstm_dim, with_batch=True,
name='char_lstm_for')
char_lstm_rev = LSTM(char_dim, char_lstm_dim, with_batch=True,
name='char_lstm_rev')
char_lstm_for.link(char_layer.link(char_for_ids))
char_lstm_rev.link(char_layer.link(char_rev_ids))
char_for_output = char_lstm_for.h.dimshuffle((1, 0, 2))[
T.arange(s_len), char_pos_ids
]
char_rev_output = char_lstm_rev.h.dimshuffle((1, 0, 2))[
T.arange(s_len), char_pos_ids
]
inputs.append(char_for_output)
if char_bidirect:
inputs.append(char_rev_output)
input_dim += char_lstm_dim
#
# Capitalization feature
#
if cap_dim:
input_dim += cap_dim
cap_layer = EmbeddingLayer(n_cap, cap_dim, name='cap_layer')
inputs.append(cap_layer.link(cap_ids))
# Prepare final input
if len(inputs) != 1:
inputs = T.concatenate(inputs, axis=1)
#
# Dropout on final input
#
if dropout:
dropout_layer = DropoutLayer(p=dropout)
input_train = dropout_layer.link(inputs)
input_test = (1 - dropout) * inputs
inputs = T.switch(T.neq(is_train, 0), input_train, input_test)
# LSTM for words
word_lstm_for = LSTM(input_dim, word_lstm_dim, with_batch=False,
name='word_lstm_for')
word_lstm_rev = LSTM(input_dim, word_lstm_dim, with_batch=False,
name='word_lstm_rev')
word_lstm_for.link(inputs)
word_lstm_rev.link(inputs[::-1, :])
word_for_output = word_lstm_for.h
word_rev_output = word_lstm_rev.h[::-1, :]
if word_bidirect:
final_output = T.concatenate(
[word_for_output, word_rev_output],
axis=1
)
tanh_layer = HiddenLayer(2 * word_lstm_dim, word_lstm_dim,
name='tanh_layer', activation='tanh')
final_output = tanh_layer.link(final_output)
else:
final_output = word_for_output
# Sentence to Named Entity tags - Score
final_layer_init = HiddenLayer(word_lstm_dim, n_tags_loaded, name='final_layer',
activation=(None))
tags_loaded_scores = final_layer_init.link(final_output)
print word_lstm_dim+n_tags_loaded
final_layer = HiddenLayer(word_lstm_dim+n_tags_loaded, n_tags, name='final_layer_new',
activation=('softmax'))
final_out_new = T.concatenate([final_output, tags_loaded_scores], axis=1)
tags_scores = final_layer.link(final_out_new)
# No CRF
cost = T.nnet.categorical_crossentropy(tags_scores, tag_ids).mean()
# Network parameters
params = []
if word_dim:
self.add_component(word_layer)
params.extend(word_layer.params)
if char_dim:
self.add_component(char_layer)
self.add_component(char_lstm_for)
params.extend(char_layer.params)
params.extend(char_lstm_for.params)
if char_bidirect:
self.add_component(char_lstm_rev)
params.extend(char_lstm_rev.params)
self.add_component(word_lstm_for)
params.extend(word_lstm_for.params)
if word_bidirect:
self.add_component(word_lstm_rev)
params.extend(word_lstm_rev.params)
if cap_dim:
self.add_component(cap_layer)
params.extend(cap_layer.params)
self.add_component(final_layer)
params.extend(final_layer.params)
if word_bidirect:
self.add_component(tanh_layer)
params.extend(tanh_layer.params)
# Prepare train and eval inputs
eval_inputs = []
if word_dim:
eval_inputs.append(word_ids)
if char_dim:
eval_inputs.append(char_for_ids)
if char_bidirect:
eval_inputs.append(char_rev_ids)
eval_inputs.append(char_pos_ids)
if cap_dim:
eval_inputs.append(cap_ids)
train_inputs = eval_inputs + [tag_ids]
# Parse optimization method parameters
if "-" in lr_method:
lr_method_name = lr_method[:lr_method.find('-')]
lr_method_parameters = {}
for x in lr_method[lr_method.find('-') + 1:].split('-'):
split = x.split('_')
assert len(split) == 2
lr_method_parameters[split[0]] = float(split[1])
else:
lr_method_name = lr_method
lr_method_parameters = {}
# Compile training function
print 'Compiling...'
if training:
updates = Optimization(clip=5.0).get_updates(lr_method_name, cost, params, **lr_method_parameters)
f_train = theano.function(
inputs=train_inputs,
outputs=cost,
updates=updates,
givens=({is_train: np.cast['int32'](1)} if dropout else {})
)
else:
f_train = None
# Compile evaluation function
if not crf:
f_eval = theano.function(
inputs=eval_inputs,
outputs=tags_scores,
givens=({is_train: np.cast['int32'](0)} if dropout else {})
)
return f_train, f_eval
def build(self, parameters):
#{{{
"""
Build the network.
"""
#some parameters
dropout = parameters['dropout']
char_dim = parameters['char_dim']
char_lstm_dim = parameters['char_lstm_dim']
char_bidirect = parameters['char_bidirect']
word_dim = parameters['word_dim']
word_lstm_dim = parameters['word_lstm_dim']
word_bidirect = parameters['word_bidirect']
lr_method = parameters['lr_method']
pre_emb = parameters['pre_emb']
crf = parameters['crf']
cap_dim = parameters['cap_dim']
training = parameters['training']
features = parameters['features']
# Training parameters
n_words = len(self.id_to_word)
n_chars = len(self.id_to_char)
n_tags = len(self.id_to_tag)
self.output_dim = len(self.id_to_tag)
self.transitions = shared((self.output_dim + 1, self.output_dim),
'transitions')
# Number of capitalization features
if cap_dim:
n_cap = 4
if features is not None and features['lemma']['isUsed']:
lemma_ids = T.ivector(name='lemma_ids')
if features is not None and features['pos']['isUsed']:
pos_ids = T.ivector(name='pos_ids')
if features is not None and features['chunk']['isUsed']:
chunk_ids = T.ivector(name='chunk_ids')
if features is not None and features['NER']['isUsed']:
dic_ids = T.ivector(name='dic_ids')
# Network variables
is_train = T.iscalar('is_train')
word_ids = T.ivector(name='word_ids')
char_for_ids = T.imatrix(name='char_for_ids')
char_rev_ids = T.imatrix(name='char_rev_ids')
char_pos_ids = T.ivector(name='char_pos_ids')
tag_ids = T.ivector(name='tag_ids')
if cap_dim:
cap_ids = T.ivector(name='cap_ids')
# Sentence length
s_len = (word_ids if word_dim else char_pos_ids).shape[0]
# Final input (all word features)
input_dim = 0
inputs = []
# Word inputs
#{{{
if word_dim:
input_dim += word_dim
word_layer = EmbeddingLayer(n_words, word_dim, name='word_layer')
word_input = word_layer.link(word_ids)
#for attention
inputs.append(word_input)
# Initialize with pretrained embeddings
if pre_emb and training:
new_weights = word_layer.embeddings.get_value()
print 'Loading pretrained embeddings from %s...' % pre_emb
pretrained = {}
emb_invalid = 0
for i, line in enumerate(codecs.open(pre_emb, 'r', 'utf-8')):
line = line.rstrip().split()
if len(line) == word_dim + 1:
pretrained[line[0]] = np.array(
[float(x) for x in line[1:]]).astype(np.float32)
else:
emb_invalid += 1
if emb_invalid > 0:
print 'WARNING: %i invalid lines' % emb_invalid
c_found = 0
c_lower = 0
c_zeros = 0
# Lookup table initialization
for i in xrange(n_words):
word = self.id_to_word[i]
if word in pretrained:
new_weights[i] = pretrained[word]
c_found += 1
elif word.lower() in pretrained:
new_weights[i] = pretrained[word.lower()]
c_lower += 1
elif re.sub('\d', '0', word.lower()) in pretrained:
new_weights[i] = pretrained[re.sub(
'\d', '0', word.lower())]
c_zeros += 1
word_layer.embeddings.set_value(new_weights)
print 'Loaded %i pretrained embeddings.' % len(pretrained)
print(
'%i / %i (%.4f%%) words have been initialized with '
'pretrained embeddings.') % (
c_found + c_lower + c_zeros, n_words, 100. *
(c_found + c_lower + c_zeros) / n_words)
print(
'%i found directly, %i after lowercasing, '
'%i after lowercasing + zero.') % (
c_found, c_lower, c_zeros) #}}}
# Chars inputs
#{{{
if char_dim:
input_dim += char_lstm_dim
char_layer = EmbeddingLayer(n_chars, char_dim, name='char_layer')
char_lstm_for = LSTM(char_dim,
char_lstm_dim,
with_batch=True,
name='char_lstm_for')
char_lstm_rev = LSTM(char_dim,
char_lstm_dim,
with_batch=True,
name='char_lstm_rev')
char_lstm_for.link(char_layer.link(char_for_ids))
char_lstm_rev.link(char_layer.link(char_rev_ids))
char_for_output = char_lstm_for.h.dimshuffle(
(1, 0, 2))[T.arange(s_len), char_pos_ids]
char_rev_output = char_lstm_rev.h.dimshuffle(
(1, 0, 2))[T.arange(s_len), char_pos_ids]
inputs.append(char_for_output)
if char_bidirect:
inputs.append(char_rev_output)
input_dim += char_lstm_dim
#}}}
# Capitalization feature
#
if cap_dim:
input_dim += cap_dim
cap_layer = EmbeddingLayer(n_cap, cap_dim, name='cap_layer')
inputs.append(cap_layer.link(cap_ids))
# Prepare final input
if len(inputs) != 1:
inputs = T.concatenate(inputs, axis=1)
#
# Dropout on final input
#
if dropout:
dropout_layer = DropoutLayer(p=dropout)
input_train = dropout_layer.link(inputs)
input_test = (1 - dropout) * inputs
inputs = T.switch(T.neq(is_train, 0), input_train, input_test)
# LSTM for words
word_lstm_for = LSTM(input_dim,
word_lstm_dim,
with_batch=False,
name='word_lstm_for')
word_lstm_rev = LSTM(input_dim,
word_lstm_dim,
with_batch=False,
name='word_lstm_rev')
word_lstm_for.link(inputs)
word_lstm_rev.link(inputs[::-1, :])
word_for_output = word_lstm_for.h
word_rev_output = word_lstm_rev.h[::-1, :]
if word_bidirect:
final_output = T.concatenate([word_for_output, word_rev_output],
axis=1)
tanh_layer = HiddenLayer(2 * word_lstm_dim,
word_lstm_dim,
name='tanh_layer',
activation='tanh')
final_output = tanh_layer.link(final_output)
else:
final_output = word_for_output
# Sentence to Named Entity tags - Score
final_layer = HiddenLayer(word_lstm_dim,
n_tags,
name='final_layer',
activation=(None if crf else 'softmax'))
tags_scores = final_layer.link(final_output)
# No CRF
if not crf:
cost = T.nnet.categorical_crossentropy(tags_scores, tag_ids).mean()
# CRF
else:
#all_paths_scores = forward(observations, self.transitions)
#cost = - (self.modelScore(tag_ids,tags_scores,s_len) - all_paths_scores)
#real_path_score=self.modelScore(tag_ids,tags_scores,tag_ids.shape[0]) ;
#error=real_path_score+self.noiseLoss(tags_scores,tag_ids,0.5);
#cost=-error;
#cost=self.likehoodLoss(tags_scores,tag_ids,observations,2)
real_path_score = tags_scores[T.arange(s_len), tag_ids].sum()
# Score from transitions
padded_tags_ids = T.concatenate([[n_tags], tag_ids], axis=0)
real_path_score += self.transitions[
padded_tags_ids[T.arange(s_len)],
padded_tags_ids[T.arange(s_len) + 1]].sum()
all_paths_scores = forward(tags_scores, self.transitions)
cost = -(real_path_score - all_paths_scores)
# Network parameters
params = []
if word_dim:
self.add_component(word_layer)
params.extend(word_layer.params)
if char_dim:
self.add_component(char_layer)
self.add_component(char_lstm_for)
params.extend(char_layer.params)
params.extend(char_lstm_for.params)
if char_bidirect:
self.add_component(char_lstm_rev)
params.extend(char_lstm_rev.params)
self.add_component(word_lstm_for)
params.extend(word_lstm_for.params)
if word_bidirect:
self.add_component(word_lstm_rev)
params.extend(word_lstm_rev.params)
if cap_dim:
self.add_component(cap_layer)
params.extend(cap_layer.params)
self.add_component(final_layer)
params.extend(final_layer.params)
if crf:
self.add_component(self.transitions)
params.append(self.transitions)
if word_bidirect:
self.add_component(tanh_layer)
params.extend(tanh_layer.params)
# Prepare train and eval inputs
eval_inputs = []
if word_dim:
eval_inputs.append(word_ids)
if char_dim:
eval_inputs.append(char_for_ids)
if char_bidirect:
eval_inputs.append(char_rev_ids)
eval_inputs.append(char_pos_ids)
if cap_dim:
eval_inputs.append(cap_ids)
train_inputs = eval_inputs + [tag_ids]
# Parse optimization method parameters
if "-" in lr_method:
lr_method_name = lr_method[:lr_method.find('-')]
lr_method_parameters = {}
for x in lr_method[lr_method.find('-') + 1:].split('-'):
split = x.split('_')
assert len(split) == 2
lr_method_parameters[split[0]] = float(split[1])
else:
lr_method_name = lr_method
lr_method_parameters = {}
# Compile training function
print 'Compiling...'
if training:
import optimizers
self.optimizer = optimizers.RMSprop(lr=0.001)
updates = Optimization(clip=5.0).get_updates(
lr_method_name, cost, params, **lr_method_parameters)
self.constraints = {}
#updates = self.optimizer.get_updates(params,self.constraints,cost);
f_train = theano.function(inputs=train_inputs,
outputs=cost,
updates=updates,
givens=({
is_train: np.cast['int32'](1)
} if dropout else {}))
#for debug
#f_Debug = theano.function(
# inputs=train_inputs,
# outputs=cost,
# updates=self.update,
# givens=({is_train: np.cast['int32'](1)} if dropout else {})
#)
#debug end
else:
f_train = None
# Compile evaluation function
if not crf:
f_eval = theano.function(inputs=eval_inputs,
outputs=tags_scores,
givens=({
is_train: np.cast['int32'](0)
} if dropout else {}))
else:
f_eval = theano.function(inputs=eval_inputs,
outputs=forward(
tags_scores,
self.transitions,
viterbi=True,
return_alpha=False,
return_best_sequence=True),
givens=({
is_train: np.cast['int32'](0)
} if dropout else {}))
return f_train, f_eval
def build4(self, parameters):
#{{{
"""
Build the network.
"""
#some parameters
dropout = parameters['dropout']
char_dim = parameters['char_dim']
char_lstm_dim = parameters['char_lstm_dim']
char_bidirect = parameters['char_bidirect']
word_dim = parameters['word_dim']
word_lstm_dim = parameters['word_lstm_dim']
word_bidirect = parameters['word_bidirect']
lr_method = parameters['lr_method']
pre_emb = parameters['pre_emb']
crf = parameters['crf']
cap_dim = parameters['cap_dim']
training = parameters['training']
features = parameters['features']
useAttend = parameters['useAttend']
if useAttend:
reloadParam = parameters['loading']
else:
reloadParam = None
if reloadParam is not None:
reloadPath = parameters['loading_path']
sentencesLevelLoss = parameters['sentencesLevelLoss']
# Training parameters
n_words = len(self.id_to_word)
n_chars = len(self.id_to_char)
n_tags = len(self.id_to_tag)
self.output_dim = len(self.id_to_tag)
self.transitions = shared((self.output_dim + 1, self.output_dim),
'transitions')
# Number of capitalization features
if cap_dim:
n_cap = 4
# Network variables
is_train = T.iscalar('is_train')
word_ids = T.ivector(name='word_ids')
wordTrue_ids = T.ivector(name='wordTrue_ids')
char_for_ids = T.imatrix(name='char_for_ids')
char_rev_ids = T.imatrix(name='char_rev_ids')
char_pos_ids = T.ivector(name='char_pos_ids')
docLen = T.ivector(name='docLen')
tag_ids = T.ivector(name='tag_ids')
if cap_dim:
cap_ids = T.ivector(name='cap_ids')
#some features
if features is not None and features['lemma']['isUsed']:
lemma_ids = T.ivector(name='lemma_ids')
if features is not None and features['pos']['isUsed']:
pos_ids = T.ivector(name='pos_ids')
if features is not None and features['chunk']['isUsed']:
chunk_ids = T.ivector(name='chunk_ids')
if features is not None and features['dic']['isUsed']:
dic_ids = T.ivector(name='dic_ids')
# Sentence length
s_len = (word_ids if word_dim else char_pos_ids).shape[0]
# Final input (all word features)
input_dim = 0
inputs = []
# Word inputs
#{{{
if word_dim:
input_dim += word_dim
word_layer = EmbeddingLayer(n_words, word_dim, name='word_layer')
word_input = word_layer.link(word_ids)
wordTrue_input = word_layer.link(wordTrue_ids)
inputs.append(word_input)
# Initialize with pretrained embeddings
if pre_emb and training:
new_weights = word_layer.embeddings.get_value()
print 'Loading pretrained embeddings from %s...' % pre_emb
pretrained = {}
emb_invalid = 0
for i, line in enumerate(codecs.open(pre_emb, 'r', 'utf-8')):
line = line.rstrip().split()
if len(line) == word_dim + 1:
pretrained[line[0]] = np.array(
[float(x) for x in line[1:]]).astype(np.float32)
else:
emb_invalid += 1
if emb_invalid > 0:
print 'WARNING: %i invalid lines' % emb_invalid
c_found = 0
c_lower = 0
c_zeros = 0
# Lookup table initialization
for i in xrange(n_words):
word = self.id_to_word[i]
if word in pretrained:
new_weights[i] = pretrained[word]
c_found += 1
elif word.lower() in pretrained:
new_weights[i] = pretrained[word.lower()]
c_lower += 1
elif re.sub('\d', '0', word.lower()) in pretrained:
new_weights[i] = pretrained[re.sub(
'\d', '0', word.lower())]
c_zeros += 1
word_layer.embeddings.set_value(new_weights)
print 'Loaded %i pretrained embeddings.' % len(pretrained)
print(
'%i / %i (%.4f%%) words have been initialized with '
'pretrained embeddings.') % (
c_found + c_lower + c_zeros, n_words, 100. *
(c_found + c_lower + c_zeros) / n_words)
print(
'%i found directly, %i after lowercasing, '
'%i after lowercasing + zero.') % (
c_found, c_lower, c_zeros) #}}}
# Chars inputs
#{{{
if char_dim:
input_dim += char_lstm_dim
char_layer = EmbeddingLayer(n_chars, char_dim, name='char_layer')
char_lstm_for = LSTM(char_dim,
char_lstm_dim,
with_batch=True,
name='char_lstm_for')
char_lstm_rev = LSTM(char_dim,
char_lstm_dim,
with_batch=True,
name='char_lstm_rev')
char_lstm_for.link(char_layer.link(char_for_ids))
char_lstm_rev.link(char_layer.link(char_rev_ids))
char_for_output = char_lstm_for.h.dimshuffle(
(1, 0, 2))[T.arange(s_len), char_pos_ids]
char_rev_output = char_lstm_rev.h.dimshuffle(
(1, 0, 2))[T.arange(s_len), char_pos_ids]
char_output = T.concatenate([char_for_output, char_rev_output],
axis=-1)
inputs.append(char_for_output)
if char_bidirect:
inputs.append(char_rev_output)
input_dim += char_lstm_dim
#}}}
# Capitalization feature
#
if cap_dim:
input_dim += cap_dim
cap_layer = EmbeddingLayer(n_cap, cap_dim, name='cap_layer')
inputs.append(cap_layer.link(cap_ids))
#add feature
#{{{
if features is not None and features['lemma']['isUsed']:
lemma_layer = EmbeddingLayer(features['lemma']['num'],
features['lemma']['dim'],
name='lemma_layer')
if features['lemma']['pre_emb'] is not "":
new_weights = lemma_layer.embeddings.get_value()
loadPreEmbFeatures(features['lemma']['pre_emb'],
features['feature_to_id_map']['lemma'],
new_weights,
lower=True)
lemma_layer.embeddings.set_value(new_weights)
lemma_output = lemma_layer.link(lemma_ids)
if features['lemma']['lstm-input']:
input_dim += features['lemma']['dim']
inputs.append(lemma_output)
if features is not None and features['pos']['isUsed']:
pos_layer = EmbeddingLayer(features['pos']['num'],
features['pos']['dim'],
name='pos_layer')
if features['pos']['pre_emb'] is not "":
new_weights = pos_layer.embeddings.get_value()
loadPreEmbFeatures(features['pos']['pre_emb'],
features['feature_to_id_map']['pos'],
new_weights)
pos_layer.embeddings.set_value(new_weights)
pos_output = pos_layer.link(pos_ids)
if features['pos']['lstm-input']:
input_dim += features['pos']['dim']
inputs.append(pos_output)
if features is not None and features['chunk']['isUsed']:
chunk_layer = EmbeddingLayer(features['chunk']['num'],
features['chunk']['dim'],
name='chunk_layer')
chunk_output = chunk_layer.link(chunk_ids)
if features['chunk']['lstm-input']:
input_dim += features['chunk']['dim']
inputs.append(chunk_output)
if features is not None and features['dic']['isUsed']:
dic_layer = EmbeddingLayer(features['dic']['num'],
features['dic']['dim'],
name='dic_layer')
dic_output = dic_layer.link(dic_ids)
if features['dic']['lstm-input']:
input_dim += features['dic']['dim']
inputs.append(dic_output)
#}}}
# Prepare final input
if len(inputs) != 1:
inputs = T.concatenate(inputs, axis=1)
#
# Dropout on final input
#
if dropout:
dropout_layer = DropoutLayer(p=dropout)
input_train = dropout_layer.link(inputs)
input_test = (1 - dropout) * inputs
inputs = T.switch(T.neq(is_train, 0), input_train, input_test)
# LSTM for words
word_lstm_for = LSTM(input_dim,
word_lstm_dim,
with_batch=False,
name='word_lstm_for')
word_lstm_rev = LSTM(input_dim,
word_lstm_dim,
with_batch=False,
name='word_lstm_rev')
if sentencesLevelLoss:
def sentLSTM(i, output, input, lenVec):
#{{{
Len = lenVec[i]
accLen = lenVec[:i].sum()
currentInput = input[accLen:accLen + Len]
word_lstm_for.link(currentInput)
word_lstm_rev.link(currentInput[::-1, :])
wordForOutput = word_lstm_for.h
wordRevOutput = word_lstm_rev.h[::-1, :]
finalOutput = T.concatenate([wordForOutput, wordRevOutput],
axis=-1)
output = T.set_subtensor(output[accLen:accLen + Len],
finalOutput)
return output
#}}}
result, update = theano.scan(
fn=sentLSTM,
outputs_info=T.zeros((inputs.shape[0], word_lstm_dim * 2),
dtype='float32'),
sequences=[T.arange(docLen.shape[0])],
non_sequences=[inputs, docLen])
word_lstm_for.link(inputs)
word_lstm_rev.link(inputs[::-1, :])
word_for_output = word_lstm_for.h
word_for_c = word_lstm_for.c
word_rev_output = word_lstm_rev.h[::-1, :]
word_rev_c = word_lstm_rev.c[::-1, :]
final_c = T.concatenate([word_for_c, word_rev_c], axis=-1)
final_output = result[-1]
else:
word_lstm_for.link(inputs)
word_lstm_rev.link(inputs[::-1, :])
word_for_output = word_lstm_for.h
word_for_c = word_lstm_for.c
word_rev_output = word_lstm_rev.h[::-1, :]
word_rev_c = word_lstm_rev.c[::-1, :]
final_output = T.concatenate([word_for_output, word_rev_output],
axis=-1)
final_c = T.concatenate([word_for_c, word_rev_c], axis=-1)
if useAttend:
#attention layer
attended = []
attendedDim = 0
if features is not None and features['word']['attended']:
attended.append(wordTrue_input)
attendedDim += word_dim
if features is not None and features['char']['attended']:
attended.append(char_output)
attendedDim += char_lstm_dim * 2
if features is not None and features['lemma']['attended']:
attended.append(lemma_output)
attendedDim += features['lemma']['dim']
if features is not None and features['pos']['attended']:
attended.append(pos_output)
attendedDim += features['pos']['dim']
if features is not None and features['chunk']['attended']:
attended.append(chunk_output)
attendedDim += features['chunk']['dim']
if features is not None and features['dic']['attended']:
attended.append(dic_output)
attendedDim += features['dic']['dim']
attention_layer = AttentionLayer(
attended_dim=attendedDim,
state_dim=attendedDim,
#attention_layer=AttentionLayer(attended_dim=word_lstm_dim*2,
# state_dim=word_lstm_dim*2,
source_dim=word_lstm_dim * 2,
scoreFunName=parameters['attenScoreFun'],
name='attention_layer')
if len(attended) > 1:
attendedInput = T.concatenate(attended, axis=-1)
else:
attendedInput = attended[0]
final_output = attention_layer.link(attendedInput, attendedInput,
final_output)
#using lstm_state to compute attention
#final_output=attention_layer.link(final_output,final_c,final_output);
self.energy = attention_layer.energy
else:
final_output = final_output
tanh_layer = HiddenLayer(2 * word_lstm_dim,
word_lstm_dim,
name='tanh_layer',
activation='tanh')
final_output = tanh_layer.link(final_output)
# Sentence to Named Entity tags - Score
final_layer = HiddenLayer(word_lstm_dim,
n_tags,
name='final_layer',
activation=(None if crf else 'softmax'))
tags_scores = final_layer.link(final_output)
# No CRF
if not crf:
cost = T.nnet.categorical_crossentropy(tags_scores, tag_ids).mean()
# CRF
else:
if sentencesLevelLoss:
#calcuate loss according to sentence instead of docLen
def sentLoss(i, scores, trueIds, transitions, lenVec):
#{{{
Len = lenVec[i]
accLen = lenVec[:i].sum()
currentTagsScores = scores[accLen:accLen + Len]
currentIds = trueIds[accLen:accLen + Len]
real_path_score = currentTagsScores[T.arange(Len),
currentIds].sum()
# Score from transitions
padded_tags_ids = T.concatenate([[n_tags], currentIds],
axis=0)
real_path_score += transitions[
padded_tags_ids[T.arange(Len)],
padded_tags_ids[T.arange(Len) + 1]].sum()
all_paths_scores = forward(currentTagsScores, transitions)
cost = -(real_path_score - all_paths_scores)
return cost
#}}}
result, update = theano.scan(
fn=sentLoss,
outputs_info=None,
sequences=[T.arange(docLen.shape[0])],
non_sequences=[
tags_scores, tag_ids, self.transitions, docLen
])
cost = result.sum()
else:
real_path_score = tags_scores[T.arange(s_len), tag_ids].sum()
# Score from transitions
padded_tags_ids = T.concatenate([[n_tags], tag_ids], axis=0)
real_path_score += self.transitions[
padded_tags_ids[T.arange(s_len)],
padded_tags_ids[T.arange(s_len) + 1]].sum()
all_paths_scores = forward(tags_scores, self.transitions)
cost = -(real_path_score - all_paths_scores)
# Network parameters
params = []
if word_dim:
self.add_component(word_layer)
params.extend(word_layer.params)
if char_dim:
self.add_component(char_layer)
self.add_component(char_lstm_for)
params.extend(char_layer.params)
params.extend(char_lstm_for.params)
if char_bidirect:
self.add_component(char_lstm_rev)
params.extend(char_lstm_rev.params)
self.add_component(word_lstm_for)
params.extend(word_lstm_for.params)
if word_bidirect:
self.add_component(word_lstm_rev)
params.extend(word_lstm_rev.params)
if cap_dim:
self.add_component(cap_layer)
params.extend(cap_layer.params)
self.add_component(final_layer)
params.extend(final_layer.params)
if crf:
self.add_component(self.transitions)
params.append(self.transitions)
if word_bidirect:
self.add_component(tanh_layer)
params.extend(tanh_layer.params)
#add feature layer
if features is not None and features['lemma']['isUsed']:
self.add_component(lemma_layer)
params.extend(lemma_layer.params)
if features is not None and features['pos']['isUsed']:
self.add_component(pos_layer)
params.extend(pos_layer.params)
if features is not None and features['chunk']['isUsed']:
self.add_component(chunk_layer)
params.extend(chunk_layer.params)
if features is not None and features['dic']['isUsed']:
self.add_component(dic_layer)
params.extend(dic_layer.params)
if useAttend and reloadParam:
#reload pre-train params
model_path = self.model_path
self.model_path = reloadPath
print "loading:", self.model_path
self.reload(features)
self.model_path = model_path
if useAttend:
#add attention_layer
self.add_component(attention_layer)
params.extend(attention_layer.params)
# Prepare train and eval inputs
eval_inputs = []
if word_dim:
eval_inputs.append(word_ids)
if char_dim:
eval_inputs.append(char_for_ids)
if char_bidirect:
eval_inputs.append(char_rev_ids)
eval_inputs.append(char_pos_ids)
if cap_dim:
eval_inputs.append(cap_ids)
if useAttend:
eval_inputs.append(wordTrue_ids)
if sentencesLevelLoss:
eval_inputs.append(docLen)
#add feature input
if features is not None and features['lemma']['isUsed']:
eval_inputs.append(lemma_ids)
if features is not None and features['pos']['isUsed']:
eval_inputs.append(pos_ids)
if features is not None and features['chunk']['isUsed']:
eval_inputs.append(chunk_ids)
if features is not None and features['dic']['isUsed']:
eval_inputs.append(dic_ids)
train_inputs = eval_inputs + [tag_ids]
# Parse optimization method parameters
if "-" in lr_method:
lr_method_name = lr_method[:lr_method.find('-')]
lr_method_parameters = {}
for x in lr_method[lr_method.find('-') + 1:].split('-'):
split = x.split('_')
assert len(split) == 2
lr_method_parameters[split[0]] = float(split[1])
else:
lr_method_name = lr_method
lr_method_parameters = {}
# Compile training function
print 'Compiling...'
if training:
#constraints
if useAttend:
self.constraints = attention_layer.constraints
else:
self.constraints = {}
from keras import optimizers
self.optimizer = optimizers.SGD(lr=0.001,
momentum=0.9,
decay=0.,
nesterov=True,
clipvalue=5)
self.optimizer = optimizers.RMSprop()
#self.optimizer=SGD(lr=lr_method_parameters['lr'],clipvalue=5,gradient_noise=0.01)
updates = Optimization(clip=5.0).get_updates(
lr_method_name,
cost,
params,
constraints=self.constraints,
**lr_method_parameters)
#updates = self.optimizer.get_updates(params,self.constraints,cost);
f_train_outputs = [cost]
if useAttend:
f_train_outputs.append(self.energy)
f_train = theano.function(inputs=train_inputs,
outputs=f_train_outputs,
updates=updates,
on_unused_input='ignore',
givens=({
is_train: np.cast['int32'](1)
} if dropout else {}))
f_test = theano.function(inputs=train_inputs,
outputs=cost,
on_unused_input='ignore',
givens=({
is_train: np.cast['int32'](0)
} if dropout else {}))
self.f_test = f_test
else:
f_train = None
# Compile evaluation function
if not crf:
f_eval = theano.function(inputs=eval_inputs,
outputs=tags_scores,
givens=({
is_train: np.cast['int32'](0)
} if dropout else {}))
else:
if sentencesLevelLoss:
def sentVitebe(i, predictTag, scores, transitions, lenVec):
#{{{
Len = lenVec[i]
accLen = lenVec[:i].sum()
currentTagsScores = scores[accLen:accLen + Len]
currentPredictIds = forward(currentTagsScores,
transitions,
viterbi=True,
return_alpha=False,
return_best_sequence=True)
predictTag = T.set_subtensor(
predictTag[accLen:accLen + Len], currentPredictIds)
return predictTag
#}}}
predictTag, update = theano.scan(
fn=sentVitebe,
outputs_info=T.zeros((tags_scores.shape[0], ),
dtype='int32'),
sequences=[T.arange(docLen.shape[0])],
non_sequences=[tags_scores, self.transitions, docLen])
predictTag = predictTag[-1]
else:
predictTag = forward(tags_scores,
self.transitions,
viterbi=True,
return_alpha=False,
return_best_sequence=True)
f_eval = theano.function(inputs=eval_inputs,
outputs=predictTag,
on_unused_input='ignore',
givens=({
is_train: np.cast['int32'](0)
} if dropout else {}))
#f_AttenVisual=theano.function(
# inputs=eval_inputs,
# outputs=[predictTag,self.energy],
# on_unused_input='ignore',
# givens=({is_train: np.cast['int32'](0)} if dropout else {})
# )
#self.f_AttenVisual=f_AttenVisual;
return f_train, f_eval
def build(self,
dropout,
char_dim,
char_lstm_dim,
char_bidirect,
word_dim,
word_lstm_dim,
word_bidirect,
lr_method,
pre_emb,
crf,
cap_dim,
model_type,
training=True,
**kwargs):
"""
Build the network.
"""
# Training parameters
layer_weighting = "fixed"
n_words = len(self.id_to_word)
n_chars = len(self.id_to_char)
print "-------------------------------MODEL INFO---------------------------------------"
print "** model_type", model_type
print "** n_words, n_chars:", n_words, n_chars
print "** self.feature_maps:"
for f in self.feature_maps:
print f["name"], f
print "** self.tag_maps:"
for tm in self.tag_maps:
print tm
print "---------------------------------------------------------------------------------"
# Number of capitalization features
if cap_dim:
n_cap = 4
# Network variables
is_train = T.iscalar('is_train')
word_ids = T.ivector(name='word_ids')
char_for_ids = T.imatrix(name='char_for_ids')
char_rev_ids = T.imatrix(name='char_rev_ids')
char_pos_ids = T.ivector(name='char_pos_ids')
if cap_dim:
cap_ids = T.ivector(name='cap_ids')
features_ids = []
for f in self.feature_maps:
features_ids.append(T.ivector(name=f['name'] + '_ids'))
# Sentence length
s_len = (word_ids if word_dim else char_pos_ids).shape[0]
# Final input (all word features)
input_dim = 0
inputs = []
#
# Word inputs
#
if word_dim:
input_dim += word_dim
print "** input_dim (input_dim += word_dim)", input_dim
word_layer = EmbeddingLayer(n_words, word_dim, name='word_layer')
word_input = word_layer.link(word_ids)
inputs.append(word_input)
# Initialize with pretrained embeddings
if pre_emb and training:
new_weights = word_layer.embeddings.get_value()
print 'Loading pretrained embeddings from %s...' % pre_emb
pretrained = {}
emb_invalid = 0
for i, line in enumerate(codecs.open(pre_emb, 'r', 'utf-8')):
line = line.rstrip().split()
if len(line) == word_dim + 1:
pretrained[line[0]] = np.array(
[float(x) for x in line[1:]]).astype(np.float32)
else:
emb_invalid += 1
if emb_invalid > 0:
print 'WARNING: %i invalid lines' % emb_invalid
c_found = 0
c_lower = 0
c_zeros = 0
# Lookup table initialization
for i in xrange(n_words):
word = self.id_to_word[i]
if word in pretrained:
new_weights[i] = pretrained[word]
c_found += 1
elif word.lower() in pretrained:
new_weights[i] = pretrained[word.lower()]
c_lower += 1
elif re.sub('\d', '0', word.lower()) in pretrained:
new_weights[i] = pretrained[re.sub(
'\d', '0', word.lower())]
c_zeros += 1
word_layer.embeddings.set_value(new_weights)
print 'Loaded %i pretrained embeddings.' % len(pretrained)
print(
'%i / %i (%.4f%%) words have been initialized with '
'pretrained embeddings.') % (
c_found + c_lower + c_zeros, n_words, 100. *
(c_found + c_lower + c_zeros) / n_words)
print(
'%i found directly, %i after lowercasing, '
'%i after lowercasing + zero.') % (c_found, c_lower,
c_zeros)
#
# Chars inputs
#
if char_dim:
input_dim += char_lstm_dim
print "** input_dim (input_dim += char_lstm_dim)", input_dim
char_layer = EmbeddingLayer(n_chars, char_dim, name='char_layer')
char_lstm_for = LSTM(char_dim,
char_lstm_dim,
with_batch=True,
name='char_lstm_for')
char_lstm_rev = LSTM(char_dim,
char_lstm_dim,
with_batch=True,
name='char_lstm_rev')
char_lstm_for.link(char_layer.link(char_for_ids))
char_lstm_rev.link(char_layer.link(char_rev_ids))
char_for_output = char_lstm_for.h.dimshuffle(
(1, 0, 2))[T.arange(s_len), char_pos_ids]
char_rev_output = char_lstm_rev.h.dimshuffle(
(1, 0, 2))[T.arange(s_len), char_pos_ids]
inputs.append(char_for_output)
if char_bidirect:
inputs.append(char_rev_output)
input_dim += char_lstm_dim
print "** input_dim (input_dim += char_lstm_dim: char_bidirect)", input_dim
#
# Capitalization feature
#
if cap_dim:
input_dim += cap_dim
print "** input_dim (input_dim += cap_dim)", input_dim
cap_layer = EmbeddingLayer(n_cap, cap_dim, name='cap_layer')
inputs.append(cap_layer.link(cap_ids))
f_layers = []
for ilayer in range(len(self.feature_maps)):
f = self.feature_maps[ilayer]
input_dim += f['dim']
print "** input_dim (input_dim += f['dim'])", input_dim
af_layer = EmbeddingLayer(len(f['id_to_ftag']),
f['dim'],
name=f['name'] + '_layer')
f_layers.append(af_layer)
inputs.append(af_layer.link(features_ids[ilayer]))
# Prepare final input
inputs = T.concatenate(inputs, axis=1)
# inputs_nodropout = inputs
#
# Dropout on final input
#
if dropout:
dropout_layer = DropoutLayer(p=dropout)
input_train = dropout_layer.link(inputs)
input_test = (1 - dropout) * inputs
inputs = T.switch(T.neq(is_train, 0), input_train, input_test)
assert model_type in {
"struct", "struct_mlp", "struct_mlp2", "multilayer", "single"
}
# Network parameters: Part 1 (Common parameters)
params = []
if word_dim:
self.add_component(word_layer)
params.extend(word_layer.params)
for af_layer in f_layers:
self.add_component(af_layer)
params.extend(af_layer.params)
if char_dim:
self.add_component(char_layer)
self.add_component(char_lstm_for)
params.extend(char_layer.params)
params.extend(char_lstm_for.params)
if char_bidirect:
self.add_component(char_lstm_rev)
params.extend(char_lstm_rev.params)
if cap_dim:
self.add_component(cap_layer)
params.extend(cap_layer.params)
if model_type == "multilayer" or model_type == "single":
tags_scores_list = []
tag_ids_list = []
cost_list = []
observations_list = []
transitions_list = []
prev_input_dim = input_dim
prev_ntags = 0
prev_tags_cores = None
previous_inputs = inputs
for ilayer in range(len(self.tag_maps)):
inputs_i = previous_inputs if prev_tags_cores == None else T.concatenate(
[previous_inputs, prev_tags_cores], axis=1)
previous_inputs = inputs_i
input_dim_i = prev_input_dim + prev_ntags
print "input_dim_i for layer %d: %d" % (ilayer, input_dim_i)
word_lstm_for_i = LSTM(input_dim_i,
word_lstm_dim,
with_batch=False,
name='word_lstm_for' + str(ilayer))
word_lstm_rev_i = LSTM(input_dim_i,
word_lstm_dim,
with_batch=False,
name='word_lstm_rev' + str(ilayer))
word_lstm_for_i.link(inputs_i)
word_lstm_rev_i.link(inputs_i[::-1, :])
word_for_output_i = word_lstm_for_i.h
word_rev_output_i = word_lstm_rev_i.h[::-1, :]
if word_bidirect:
final_output_i = T.concatenate(
[word_for_output_i, word_rev_output_i], axis=1)
tanh_layer_i = HiddenLayer(2 * word_lstm_dim,
word_lstm_dim,
name='tanh_layer' + str(ilayer),
activation='tanh')
final_output_i = tanh_layer_i.link(final_output_i)
else:
final_output_i = word_for_output_i
n_tags_i = len(self.tag_maps[ilayer]['id_to_tag'])
final_layer_i = HiddenLayer(
word_lstm_dim,
n_tags_i,
name='final_layer' + str(ilayer),
activation=(None if crf else 'softmax'))
tags_scores_i = final_layer_i.link(final_output_i)
tag_ids_i = T.ivector(name='tag_ids' +
str(ilayer)) # input tags of layer i
# No CRF
if not crf:
cost_i = T.nnet.categorical_crossentropy(
tags_scores_i, tag_ids_i).mean()
# CRF
else:
transitions_i = shared((n_tags_i + 2, n_tags_i + 2),
'transitions' + str(ilayer))
small1 = -1000
b_s1 = np.array([[small1] * n_tags_i + [0, small1]
]).astype(np.float32)
e_s1 = np.array([[small1] * n_tags_i + [small1, 0]
]).astype(np.float32)
observations_i = T.concatenate(
[tags_scores_i, small1 * T.ones((s_len, 2))], axis=1)
observations_i = T.concatenate(
[b_s1, observations_i, e_s1], axis=0)
# Score from tags
real_path_score1 = tags_scores_i[T.arange(s_len),
tag_ids_i].sum()
# Score from transitions
b_id1 = theano.shared(
value=np.array([n_tags_i], dtype=np.int32))
e_id1 = theano.shared(
value=np.array([n_tags_i + 1], dtype=np.int32))
padded_tags_ids1 = T.concatenate([b_id1, tag_ids_i, e_id1],
axis=0)
real_path_score1 += transitions_i[
padded_tags_ids1[T.arange(s_len + 1)],
padded_tags_ids1[T.arange(s_len + 1) + 1]].sum()
all_paths_scores1 = forward(observations_i, transitions_i)
cost_i = -(real_path_score1 - all_paths_scores1)
observations_list.append(observations_i)
transitions_list.append(transitions_i)
prev_input_dim = input_dim_i
prev_ntags = n_tags_i
prev_tags_cores = tags_scores_i * 1
cost_list.append(cost_i) # add cost of layer i into cost list
tags_scores_list.append(tags_scores_i)
tag_ids_list.append(tag_ids_i)
# Network parameters: Part 2 (add parameters of mutilayer architectures)
self.add_component(word_lstm_for_i)
params.extend(word_lstm_for_i.params) #1
if word_bidirect:
self.add_component(word_lstm_rev_i)
params.extend(word_lstm_rev_i.params) #2
self.add_component(final_layer_i)
params.extend(final_layer_i.params) #3
if crf:
self.add_component(transitions_i)
params.append(transitions_i) #4
if word_bidirect:
self.add_component(tanh_layer_i)
params.extend(tanh_layer_i.params) #5
# end for loop
elif model_type == "struct" or model_type.startswith("struct_mlp"):
# begin step 1: Using BI-LSTM to encode the sequence
word_lstm_for = LSTM(input_dim,
word_lstm_dim,
with_batch=False,
name='word_lstm_for')
word_lstm_rev = LSTM(input_dim,
word_lstm_dim,
with_batch=False,
name='word_lstm_rev')
word_lstm_for.link(inputs)
word_lstm_rev.link(inputs[::-1, :])
word_for_output = word_lstm_for.h
word_rev_output = word_lstm_rev.h[::-1, :]
if word_bidirect:
lstm_output = T.concatenate([word_for_output, word_rev_output],
axis=1)
tanh_layer = HiddenLayer(2 * word_lstm_dim,
word_lstm_dim,
name='tanh_layer',
activation='tanh')
lstm_output = tanh_layer.link(lstm_output)
else:
lstm_output = word_for_output
# end step 1: final_output is the list of hidden states. Shapes of hidden state is
prev_ntags = 0
tags_scores_list = []
prev_tags_cores = None
final_layer_list = []
final_output = lstm_output
mlp_list = []
if model_type == "struct":
for ilayer in range(0, len(self.tag_maps)):
n_tags_i = len(self.tag_maps[ilayer]['id_to_tag'])
final_output = final_output if prev_tags_cores == None else T.concatenate(
[final_output, prev_tags_cores], axis=1)
final_layer_i = HiddenLayer(
word_lstm_dim + prev_ntags,
n_tags_i,
name='final_layer_' + str(ilayer),
activation=(None if crf else 'softmax'))
tags_scores_i = final_layer_i.link(final_output)
prev_ntags += n_tags_i
prev_tags_cores = tags_scores_i
tags_scores_list.append(tags_scores_i)
final_layer_list.append(final_layer_i)
elif model_type.startswith("struct_mlp"):
for ilayer in range(0, len(self.tag_maps)):
n_tags_i = len(self.tag_maps[ilayer]['id_to_tag'])
final_output = final_output if prev_tags_cores == None else T.concatenate(
[final_output, prev_tags_cores], axis=1)
if model_type == "struct_mlp2":
mlp_sizes = [
word_lstm_dim + prev_ntags, word_lstm_dim,
word_lstm_dim
]
else:
mlp_sizes = [word_lstm_dim + prev_ntags, word_lstm_dim]
mlp_input = final_output
for j in range(len(mlp_sizes) - 1):
mlp_layer = HiddenLayer(mlp_sizes[j],
mlp_sizes[j + 1],
name="mlp" + str(j + 1) +
"_layer_" + str(ilayer),
activation="tanh")
mlp_input = mlp_layer.link(mlp_input)
mlp_list.append(mlp_layer)
final_layer_i = HiddenLayer(
word_lstm_dim,
n_tags_i,
name='final_layer_' + str(ilayer),
activation=(None if crf else 'softmax'))
tags_scores_i = final_layer_i.link(mlp_input)
# # unroll version
# mlp1_layer_i = HiddenLayer(word_lstm_dim + prev_ntags, word_lstm_dim,
# name="mlp1_layer_" + str(ilayer), activation="tanh")
# mlp1_layer_i_out = mlp1_layer_i.link(final_output)
#
# mlp2_layer_i = HiddenLayer(word_lstm_dim, word_lstm_dim,
# name="mlp2_layer_" + str(ilayer), activation="tanh")
# mlp2_layer_i_out = mlp2_layer_i.link(mlp1_layer_i_out)
# mlp_list.append(mlp1_layer_i)
# mlp_list.append(mlp2_layer_i)
#
# final_layer_i = HiddenLayer(word_lstm_dim, n_tags_i, name='final_layer_' + str(ilayer),
# activation=(None if crf else 'softmax'))
# tags_scores_i = final_layer_i.link(mlp2_layer_i_out)
prev_ntags += n_tags_i
prev_tags_cores = tags_scores_i
tags_scores_list.append(tags_scores_i)
final_layer_list.append(final_layer_i)
else:
print(model_type, " is not exits !")
raise
# # unroll code
# n_tags_0 = len(self.tag_maps[0]['id_to_tag'])
# final_layer_0 = HiddenLayer(word_lstm_dim, n_tags_0, name='final_layer_0', activation=(None if crf else 'softmax'))
# tags_scores_0 = final_layer_0.link(final_output)
#
# n_tags_1 = len(self.tag_maps[1]['id_to_tag'])
# final_layer_1 = HiddenLayer(word_lstm_dim + n_tags_0, n_tags_1, name='final_layer_1', activation=(None if crf else 'softmax'))
# final_output = T.concatenate( [final_output, tags_scores_0], axis=1 )
# tags_scores_1 = final_layer_1.link(final_output)
#
# n_tags_2 = len(self.tag_maps[2]['id_to_tag'])
# final_layer_2 = HiddenLayer(word_lstm_dim + n_tags_0 + n_tags_1, n_tags_2, name='final_layer_2',
# activation=(None if crf else 'softmax'))
# final_output = T.concatenate([final_output, tags_scores_1], axis=1)
# tags_scores_2 = final_layer_2.link(final_output)
# tags_scores_list = [tags_scores_0, tags_scores_1, tags_scores_2]
tag_ids_list = []
observations_list = []
transitions_list = []
cost_list = []
for ilayer in range(0, len(self.tag_maps)):
tag_ids_i = T.ivector(name='tag_ids' +
str(ilayer)) # input tags
tag_ids_list.append(tag_ids_i)
tags_scores_i = tags_scores_list[ilayer]
n_tags_i = len(self.tag_maps[ilayer]['id_to_tag'])
# No CRF
if not crf:
cost_i = T.nnet.categorical_crossentropy(
tags_scores_i, tag_ids_i).mean()
# CRF
else:
transitions_i = shared((n_tags_i + 2, n_tags_i + 2),
'transitions' + str(ilayer))
small1 = -1000
b_s1 = np.array([[small1] * n_tags_i + [0, small1]
]).astype(np.float32)
e_s1 = np.array([[small1] * n_tags_i + [small1, 0]
]).astype(np.float32)
observations_i = T.concatenate(
[tags_scores_i, small1 * T.ones((s_len, 2))], axis=1)
observations_i = T.concatenate(
[b_s1, observations_i, e_s1], axis=0)
# Score from tags
real_path_score1 = tags_scores_i[T.arange(s_len),
tag_ids_i].sum()
# Score from transitions
b_id1 = theano.shared(
value=np.array([n_tags_i], dtype=np.int32))
e_id1 = theano.shared(
value=np.array([n_tags_i + 1], dtype=np.int32))
padded_tags_ids1 = T.concatenate([b_id1, tag_ids_i, e_id1],
axis=0)
real_path_score1 += transitions_i[
padded_tags_ids1[T.arange(s_len + 1)],
padded_tags_ids1[T.arange(s_len + 1) + 1]].sum()
all_paths_scores1 = forward(observations_i, transitions_i)
cost_i = -(real_path_score1 - all_paths_scores1)
observations_list.append(observations_i)
transitions_list.append(transitions_i)
cost_list.append(cost_i) # add cost of layer i into cost list
# Network parameters: Part 2 (add parameters of struct architectures)
self.add_component(word_lstm_for)
params.extend(word_lstm_for.params)
if word_bidirect:
self.add_component(word_lstm_rev)
params.extend(word_lstm_rev.params)
for mlp_layer in mlp_list:
self.add_component(mlp_layer)
params.extend(mlp_layer.params)
for final_layer in final_layer_list:
self.add_component(final_layer)
params.extend(final_layer.params)
# # unroll code
# self.add_component(final_layer_0)
# params.extend(final_layer_0.params)
#
# self.add_component(final_layer_1)
# params.extend(final_layer_1.params)
#
# self.add_component(final_layer_2)
# params.extend(final_layer_2.params)
if crf:
for transitions in transitions_list:
self.add_component(transitions)
params.append(transitions)
if word_bidirect:
self.add_component(tanh_layer)
params.extend(tanh_layer.params)
# elif model_type == "multilayer_original":
# print "** input_dim FOR LAYER 0 ", input_dim
# # LSTM for words
# word_lstm_for = LSTM(input_dim, word_lstm_dim, with_batch=False,
# name='word_lstm_for')
# word_lstm_rev = LSTM(input_dim, word_lstm_dim, with_batch=False,
# name='word_lstm_rev')
#
# word_lstm_for.link(inputs)
# word_lstm_rev.link(inputs[::-1, :])
# word_for_output = word_lstm_for.h
# word_rev_output = word_lstm_rev.h[::-1, :]
# if word_bidirect:
# final_output = T.concatenate(
# [word_for_output, word_rev_output],
# axis=1
# )
# tanh_layer = HiddenLayer(2 * word_lstm_dim, word_lstm_dim,
# name='tanh_layer', activation='tanh')
# final_output = tanh_layer.link(final_output)
# else:
# final_output = word_for_output
#
# # Sentence to Named Entity tags - Score
# n_tags = len(self.tag_maps[0]['id_to_tag'])
#
# final_layer = HiddenLayer(word_lstm_dim, n_tags, name='final_layer',
# activation=(None if crf else 'softmax'))
# tags_scores = final_layer.link(final_output)
# tag_ids = T.ivector(name='tag_ids0') # input tags of layer i
#
# # No CRF
# if not crf:
# cost = T.nnet.categorical_crossentropy(tags_scores, tag_ids).mean()
# # CRF
# else:
# transitions = shared((n_tags + 2, n_tags + 2), 'transitions')
#
# small = -1000
# b_s = np.array([[small] * n_tags + [0, small]]).astype(np.float32)
# e_s = np.array([[small] * n_tags + [small, 0]]).astype(np.float32)
# observations = T.concatenate(
# [tags_scores, small * T.ones((s_len, 2))],
# axis=1
# )
# observations = T.concatenate(
# [b_s, observations, e_s],
# axis=0
# )
#
# # Score from tags
# real_path_score = tags_scores[T.arange(s_len), tag_ids].sum()
#
# # Score from transitions
# b_id = theano.shared(value=np.array([n_tags], dtype=np.int32))
# e_id = theano.shared(value=np.array([n_tags + 1], dtype=np.int32))
# padded_tags_ids = T.concatenate([b_id, tag_ids, e_id], axis=0)
# real_path_score += transitions[
# padded_tags_ids[T.arange(s_len + 1)],
# padded_tags_ids[T.arange(s_len + 1) + 1]
# ].sum()
#
# all_paths_scores = forward(observations, transitions)
# cost = - (real_path_score - all_paths_scores)
#
# print "cost: ", cost
# # Network parameters
#
#
# self.add_component(word_lstm_for)
# params.extend(word_lstm_for.params) #1
#
# if word_bidirect:
# self.add_component(word_lstm_rev)
# params.extend(word_lstm_rev.params) #2
#
# self.add_component(final_layer)
# params.extend(final_layer.params) #3
#
# if crf:
# self.add_component(transitions)
# params.append(transitions) #4
#
# if word_bidirect:
# self.add_component(tanh_layer)
# params.extend(tanh_layer.params) #5
#
# #
# # layer 1 to n
# #
# tags_scores_list = [tags_scores]
# tag_ids_list = [tag_ids]
# cost_list = [cost]
# observations_list = [observations]
# transitions_list = [transitions]
# prev_input_dim = input_dim
# prev_ntags = n_tags
# prev_tags_cores = tags_scores * 1
#
# for ilayer in range(1, len(self.tag_maps)):
# inputs_i = previous_inputs * 1
# inputs_i.append(prev_tags_cores)
# previous_inputs = inputs_i * 1
#
# inputs_i = T.concatenate(inputs_i, axis=1)
# input_dim_i = prev_input_dim + prev_ntags
#
# word_lstm_for_i = LSTM(input_dim_i, word_lstm_dim, with_batch=False, name='word_lstm_for' + str(ilayer))
# word_lstm_rev_i = LSTM(input_dim_i, word_lstm_dim, with_batch=False, name='word_lstm_rev' + str(ilayer))
# word_lstm_for_i.link(inputs_i)
# word_lstm_rev_i.link(inputs_i[::-1, :])
# word_for_output_i = word_lstm_for_i.h
# word_rev_output_i = word_lstm_rev_i.h[::-1, :]
#
# if word_bidirect:
# final_output_i = T.concatenate(
# [word_for_output_i, word_rev_output_i],
# axis=1
# )
# tanh_layer_i = HiddenLayer(2 * word_lstm_dim, word_lstm_dim,
# name='tanh_layer' + str(ilayer), activation='tanh')
# final_output_i = tanh_layer_i.link(final_output_i)
# else:
# final_output_i = word_for_output_i
#
# n_tags_i = len(self.tag_maps[ilayer]['id_to_tag'])
#
# final_layer_i = HiddenLayer(word_lstm_dim, n_tags_i, name='final_layer' + str(ilayer),
# activation=(None if crf else 'softmax'))
# tags_scores_i = final_layer_i.link(final_output_i)
# tags_scores_list.append(tags_scores_i)
# tag_ids_i = T.ivector(name='tag_ids' + str(ilayer)) # input tags
# tag_ids_list.append(tag_ids_i)
#
# # No CRF
# if not crf:
# cost_i = T.nnet.categorical_crossentropy(tags_scores_i, tag_ids_i).mean()
# # CRF
# else:
# transitions_i = shared((n_tags_i + 2, n_tags_i + 2), 'transitions' + str(ilayer))
# small1 = -1000
# b_s1 = np.array([[small1] * n_tags_i + [0, small1]]).astype(np.float32)
# e_s1 = np.array([[small1] * n_tags_i + [small1, 0]]).astype(np.float32)
# observations_i = T.concatenate([tags_scores_i, small1 * T.ones((s_len, 2))], axis=1)
# observations_i = T.concatenate([b_s1, observations_i, e_s1], axis=0)
#
# # Score from tags
# real_path_score1 = tags_scores_i[T.arange(s_len), tag_ids_i].sum()
#
# # Score from transitions
# b_id1 = theano.shared(value=np.array([n_tags_i], dtype=np.int32))
# e_id1 = theano.shared(value=np.array([n_tags_i + 1], dtype=np.int32))
# padded_tags_ids1 = T.concatenate([b_id1, tag_ids_i, e_id1], axis=0)
# real_path_score1 += transitions_i[
# padded_tags_ids1[T.arange(s_len + 1)],
# padded_tags_ids1[T.arange(s_len + 1) + 1]
# ].sum()
#
# all_paths_scores1 = forward(observations_i, transitions_i)
#
# cost_i = - (real_path_score1 - all_paths_scores1)
#
# observations_list.append(observations_i)
# transitions_list.append(transitions_i)
#
# prev_input_dim = input_dim_i
# prev_ntags = n_tags_i
# prev_tags_cores = tags_scores_i * 1
# cost_list.append(cost_i) # add cost of layer i into cost list
#
# # add parameters
#
# self.add_component(word_lstm_for_i)
# params.extend(word_lstm_for_i.params)
#
# if word_bidirect:
# self.add_component(word_lstm_rev_i)
# params.extend(word_lstm_rev_i.params)
#
# self.add_component(final_layer_i)
# params.extend(final_layer_i.params)
#
# if crf:
# self.add_component(transitions_i)
# params.append(transitions_i)
#
# if word_bidirect:
# self.add_component(tanh_layer_i)
# params.extend(tanh_layer_i.params)
#
# # end for loop
if layer_weighting == "fixed":
if len(self.tag_maps) == 2:
cost_weights = np.array([0.4, 0.6])
elif len(self.tag_maps) == 3:
cost_weights = np.array([0.4, 0.3, 0.3])
else:
cost_weights = np.ones(
(len(self.tag_maps), )) / len(self.tag_maps)
costall = np.sum(cost_weights * np.array(cost_list))
else:
# https://groups.google.com/forum/#!topic/theano-users/XDG6MM83grI
weights = np.ones((len(self.tag_maps), )) / len(self.tag_maps)
cost_weights = theano.shared(weights.astype(theano.config.floatX),
name="layer_weights")
layer_weights = theano.tensor.nnet.sigmoid(cost_weights)
params.extend([cost_weights])
xx = theano.tensor.mul(layer_weights,
theano.tensor.as_tensor_variable(cost_list))
costall = theano.tensor.sum(xx)
# Prepare train and eval inputs
eval_inputs = []
if word_dim:
eval_inputs.append(word_ids)
for ilayer in range(len(self.feature_maps)):
eval_inputs.append(features_ids[ilayer])
if char_dim:
eval_inputs.append(char_for_ids)
if char_bidirect:
eval_inputs.append(char_rev_ids)
eval_inputs.append(char_pos_ids)
if cap_dim:
eval_inputs.append(cap_ids)
train_inputs = eval_inputs + tag_ids_list
print "-- train_inputs: ",
print train_inputs # [word_ids, pos_ids, chunk_ids, wh_ids, if_ids, s_ids, tag_ids, tag_ids1, tag_ids2]
# Parse optimization method parameters
if "-" in lr_method:
lr_method_name = lr_method[:lr_method.find('-')]
lr_method_parameters = {}
for x in lr_method[lr_method.find('-') + 1:].split('-'):
split = x.split('_')
assert len(split) == 2
lr_method_parameters[split[0]] = float(split[1])
else:
lr_method_name = lr_method
lr_method_parameters = {}
# Compile training function
print 'Compiling...'
if training:
# print "train_inputs[9]", train_inputs[9]
print "-- len(cost_list): ", len(cost_list)
updates = Optimization(clip=5.0).get_updates(
lr_method_name, costall, params, **lr_method_parameters)
f_train = theano.function(inputs=train_inputs,
outputs=costall,
updates=updates,
givens=({
is_train: np.cast['int32'](1)
} if dropout else {}))
else:
f_train = None
# Compile evaluation function
tags_scores_out = tags_scores_list
print "-- len(tags_scores_list): ", len(tags_scores_list)
if not crf:
f_eval = theano.function(
inputs=eval_inputs,
outputs=tags_scores_out,
givens=({
is_train: np.cast['int32'](0)
} if dropout else {}) #,
# on_unused_input='ignore'
)
else:
f_eval = theano.function(
inputs=eval_inputs,
outputs=forward_n(zip(observations_list, transitions_list),
viterbi=True,
return_alpha=False,
return_best_sequence=True),
givens=({
is_train: np.cast['int32'](0)
} if dropout else {}) #,
# on_unused_input='ignore'
)
from pprint import pprint
print "--------------------------------------------------------------"
pprint(self.components)
return f_train, f_eval # return f_train, f_eval, f_test
def build(self,
dropout,
char_dim,
char_lstm_dim,
char_bidirect,
word_dim,
word_lstm_dim,
word_bidirect,
lr_method,
pre_emb,
crf,
cap_dim,
training=True,
**kwargs
):
"""
Build the network.
"""
# Training parameters
n_words = len(self.id_to_word)
n_chars = len(self.id_to_char)
n_tags = len(self.id_to_tag)
# Number of capitalization features
if cap_dim:
n_cap = 4
# Network variables
is_train = T.iscalar('is_train')
word_ids = T.ivector(name='word_ids')
char_for_ids = T.imatrix(name='char_for_ids')
char_rev_ids = T.imatrix(name='char_rev_ids')
char_pos_ids = T.ivector(name='char_pos_ids')
tag_ids = T.ivector(name='tag_ids')
if cap_dim:
cap_ids = T.ivector(name='cap_ids')
# Sentence length
s_len = (word_ids if word_dim else char_pos_ids).shape[0]
# Final input (all word features)
input_dim = 0
inputs = []
#
# Word inputs
#
if word_dim:
input_dim += word_dim
word_layer = EmbeddingLayer(n_words, word_dim, name='word_layer')
word_input = word_layer.link(word_ids)
inputs.append(word_input)
# Initialize with pretrained embeddings
if pre_emb and training:
# Randomly generates new weights
new_weights = word_layer.embeddings.get_value()
print 'Loading pretrained embeddings from %s...' % pre_emb
# Here is where we will substitute pyemblib read function.
# Syntax: get_embedding_dict(emb_path, emb_format, first_n, vocab)
emb_format = pyemblib2.Format.Word2Vec
pretrained = get_embedding_dict(pre_emb, emb_format, 0, None)
'''
pretrained = {}
emb_invalid = 0
for i, line in enumerate(codecs.open(pre_emb, 'r', 'utf-8')):
line = line.rstrip().split()
if len(line) == word_dim + 1:
pretrained[line[0]] = np.array(
[float(x) for x in line[1:]]
).astype(np.float32)
else:
emb_invalid += 1
if emb_invalid > 0:
print 'WARNING: %i invalid lines' % emb_invalid
'''
c_found = 0
c_lower = 0
c_zeros = 0
# Lookup table initialization
for i in xrange(n_words):
word = self.id_to_word[i]
if word in pretrained:
new_weights[i] = pretrained[word]
c_found += 1
elif word.lower() in pretrained:
new_weights[i] = pretrained[word.lower()]
c_lower += 1
elif re.sub('\d', '0', word.lower()) in pretrained:
new_weights[i] = pretrained[
re.sub('\d', '0', word.lower())
]
c_zeros += 1
# This is it, this is what needs to be printed.
# "word_layer.embeddings" is a "theano.shared" object
word_layer.embeddings.set_value(new_weights)
print 'Loaded %i pretrained embeddings.' % len(pretrained)
print ('%i / %i (%.4f%%) words have been initialized with '
'pretrained embeddings.') % (
c_found + c_lower + c_zeros, n_words,
100. * (c_found + c_lower + c_zeros) / n_words
)
print ('%i found directly, %i after lowercasing, '
'%i after lowercasing + zero.') % (
c_found, c_lower, c_zeros
)
#
# Chars inputs
#
if char_dim:
input_dim += char_lstm_dim
char_layer = EmbeddingLayer(n_chars, char_dim, name='char_layer')
char_lstm_for = LSTM(char_dim, char_lstm_dim, with_batch=True,
name='char_lstm_for')
char_lstm_rev = LSTM(char_dim, char_lstm_dim, with_batch=True,
name='char_lstm_rev')
char_lstm_for.link(char_layer.link(char_for_ids))
char_lstm_rev.link(char_layer.link(char_rev_ids))
char_for_output = char_lstm_for.h.dimshuffle((1, 0, 2))[
T.arange(s_len), char_pos_ids
]
char_rev_output = char_lstm_rev.h.dimshuffle((1, 0, 2))[
T.arange(s_len), char_pos_ids
]
inputs.append(char_for_output)
if char_bidirect:
inputs.append(char_rev_output)
input_dim += char_lstm_dim
#
# Capitalization feature
#
if cap_dim:
input_dim += cap_dim
cap_layer = EmbeddingLayer(n_cap, cap_dim, name='cap_layer')
inputs.append(cap_layer.link(cap_ids))
# Prepare final input
inputs = T.concatenate(inputs, axis=1) if len(inputs) != 1 else inputs[0]
#
# Dropout on final input
#
if dropout:
dropout_layer = DropoutLayer(p=dropout)
input_train = dropout_layer.link(inputs)
input_test = (1 - dropout) * inputs
inputs = T.switch(T.neq(is_train, 0), input_train, input_test)
# LSTM for words
word_lstm_for = LSTM(input_dim, word_lstm_dim, with_batch=False,
name='word_lstm_for')
word_lstm_rev = LSTM(input_dim, word_lstm_dim, with_batch=False,
name='word_lstm_rev')
word_lstm_for.link(inputs)
word_lstm_rev.link(inputs[::-1, :])
word_for_output = word_lstm_for.h
word_rev_output = word_lstm_rev.h[::-1, :]
if word_bidirect:
final_output = T.concatenate(
[word_for_output, word_rev_output],
axis=1
)
tanh_layer = HiddenLayer(2 * word_lstm_dim, word_lstm_dim,
name='tanh_layer', activation='tanh')
final_output = tanh_layer.link(final_output)
else:
final_output = word_for_output
# Sentence to Named Entity tags - Score
final_layer = HiddenLayer(word_lstm_dim, n_tags, name='final_layer',
activation=(None if crf else 'softmax'))
tags_scores = final_layer.link(final_output)
# No CRF
if not crf:
cost = T.nnet.categorical_crossentropy(tags_scores, tag_ids).mean()
# CRF
else:
transitions = shared((n_tags + 2, n_tags + 2), 'transitions')
small = -1000
b_s = np.array([[small] * n_tags + [0, small]]).astype(np.float32)
e_s = np.array([[small] * n_tags + [small, 0]]).astype(np.float32)
observations = T.concatenate(
[tags_scores, small * T.ones((s_len, 2))],
axis=1
)
observations = T.concatenate(
[b_s, observations, e_s],
axis=0
)
# Score from tags
real_path_score = tags_scores[T.arange(s_len), tag_ids].sum()
# Score from transitions
b_id = theano.shared(value=np.array([n_tags], dtype=np.int32))
e_id = theano.shared(value=np.array([n_tags + 1], dtype=np.int32))
padded_tags_ids = T.concatenate([b_id, tag_ids, e_id], axis=0)
real_path_score += transitions[
padded_tags_ids[T.arange(s_len + 1)],
padded_tags_ids[T.arange(s_len + 1) + 1]
].sum()
all_paths_scores = forward(observations, transitions)
cost = - (real_path_score - all_paths_scores)
# Network parameters
params = []
if word_dim:
self.add_component(word_layer)
# Supposedly the commented-out line below will stop
# the model from updating the pretrained emeddings.
# params.extend(word_layer.params)
if char_dim:
self.add_component(char_layer)
self.add_component(char_lstm_for)
params.extend(char_layer.params)
params.extend(char_lstm_for.params)
if char_bidirect:
self.add_component(char_lstm_rev)
params.extend(char_lstm_rev.params)
self.add_component(word_lstm_for)
params.extend(word_lstm_for.params)
if word_bidirect:
self.add_component(word_lstm_rev)
params.extend(word_lstm_rev.params)
if cap_dim:
self.add_component(cap_layer)
params.extend(cap_layer.params)
self.add_component(final_layer)
params.extend(final_layer.params)
if crf:
self.add_component(transitions)
params.append(transitions)
if word_bidirect:
self.add_component(tanh_layer)
params.extend(tanh_layer.params)
# Prepare train and eval inputs
eval_inputs = []
if word_dim:
eval_inputs.append(word_ids)
if char_dim:
eval_inputs.append(char_for_ids)
if char_bidirect:
eval_inputs.append(char_rev_ids)
eval_inputs.append(char_pos_ids)
if cap_dim:
eval_inputs.append(cap_ids)
train_inputs = eval_inputs + [tag_ids]
# Parse optimization method parameters
if "-" in lr_method:
lr_method_name = lr_method[:lr_method.find('-')]
lr_method_parameters = {}
for x in lr_method[lr_method.find('-') + 1:].split('-'):
split = x.split('_')
assert len(split) == 2
lr_method_parameters[split[0]] = float(split[1])
else:
lr_method_name = lr_method
lr_method_parameters = {}
# Compile training function
print 'Compiling...'
if training:
# "params" supposedly contains the pretrained embedding matrix that we are updating.
# Find the "get_updates" function and figure out what it does.
updates = Optimization(clip=5.0).get_updates(lr_method_name, cost, params, **lr_method_parameters)
f_train = theano.function(
inputs=train_inputs,
outputs=cost,
updates=updates,
givens=({is_train: np.cast['int32'](1)} if dropout else {})
)
#========================================
# FUNCTION TO PRINT PRETRAINED EMBEDDINGS
# The function below takes one argument, which it prints
# along with the specified print message.
print_matrix = T.dmatrix()
print_op = printing.Print('print message')
printed_x = print_op(print_matrix)
f_print = function([print_matrix], printed_x)
#========================================
else:
f_train = None
f_print = None
# We return a tuple of things used to print the embedding so that it looks nicer.
print_tuple = [f_print, word_layer.embeddings]
# Compile evaluation function
if not crf:
f_eval = theano.function(
inputs=eval_inputs,
outputs=tags_scores,
givens=({is_train: np.cast['int32'](0)} if dropout else {})
)
else:
f_eval = theano.function(
inputs=eval_inputs,
outputs=forward(observations, transitions, viterbi=True,
return_alpha=False, return_best_sequence=True),
givens=({is_train: np.cast['int32'](0)} if dropout else {})
)
return f_train, f_eval, print_tuple