def forward(self, batch):
"""
Forward pass given data.
:param batch: List of samples containing data as transformed by the init transformer of this class.
:return: A (batch of) vectors of length equal to tagset, scoring each possible class for each word in a sentence,
for all sentences; a tensor containing the true label for each word and a tensor containing the lengths
of the sequences in descending order.
"""
hidden_static = self.init_hidden(len(batch))
hidden_dyn = self.init_hidden(len(batch))
# embed using static embeddings and pass through the recurrent layer
data, labels, char_data = data_manager.batch_sequence(
batch, self.device)
data_static = self.embedding_static(data)
data_static = self.drop(data_static)
lstm_out_static, hidden_static = self.recurrent_static(
data_static, hidden_static)
# embed using dynamic embeddings and pass through the recurrent layer
data_dynamic = self.embedding_dyn(data)
data_dynamic = self.drop(data_dynamic)
lstm_out_dyn, hidden_dyn = self.recurrent_dyn(data_dynamic, hidden_dyn)
# concatenate results
output = torch.cat([lstm_out_static, lstm_out_dyn], dim=2)
# send output to fc layer(s)
tag_space = self.hidden2tag(output.unsqueeze(1).contiguous())
tag_scores = F.log_softmax(tag_space, dim=3)
return tag_scores.view(-1, self.tagset_size), labels.view(-1)
def forward(self, batch):
"""
Forward pass given data.
:param batch: List of samples containing data as transformed by the init transformer of this class.
:return: A (batch of) vectors of length equal to tagset, scoring each possible class for each word in a sentence,
for all sentences; a tensor containing the true label for each word and a tensor containing the lengths
of the sequences in descending order.
"""
hidden = self.init_hidden(len(batch))
# pack sentences and pass through rnn
data, labels, char_data, pos, ner = data_manager.batch_sequence(
batch, self.device)
if self.embedding is not None:
data = self.embedding(data)
# If we are using more features the we concatenate everything together
if self.more_features:
data = torch.cat([data, pos, ner], 2)
data = self.drop(data)
if self.c2v_weights is not None:
batched_conv = []
char_data = self.char_embedding(char_data)
char_data = self.drop(char_data)
num_words = char_data.size()[2]
for i in range(num_words):
# get word for each batch, then convolute on the ith word of each batch and concatenate
c = char_data[:, 0, i, :, :].unsqueeze(1)
ngram1 = self.ngram1(c).view(char_data.size()[0], 1, 1, -1)
ngram2 = self.ngram2(c).view(char_data.size()[0], 1, 1, -1)
ngram3 = self.ngram3(c).view(char_data.size()[0], 1, 1, -1)
ngram1 = self.fc1(ngram1)
ngram2 = self.fc2(ngram2)
ngram3 = self.fc3(ngram3)
batched_conv.append(torch.cat([ngram1, ngram2, ngram3], dim=3))
batched_conv = torch.cat(batched_conv, dim=1).squeeze(2)
data = torch.cat([data, batched_conv], dim=2)
rec_out, hidden = self.recurrent(data, hidden)
# send output to fc layer(s)
tag_space = self.hidden2tag(rec_out.unsqueeze(1).contiguous())
tag_scores = F.log_softmax(tag_space, dim=3)
return tag_scores.view(-1, self.tagset_size), labels.view(-1)
def forward(self, batch):
"""
Forward pass given data.
:param batch: List of samples containing data as transformed by the init transformer of this class.
:return: A (batch of) vectors of length equal to tagset, scoring each possible class for each word in a sentence,
for all sentences; a tensor containing the true label for each word and a tensor containing the lengths
of the sequences in descending order.
"""
# init hidden layers for both encoder and decoder section
hidden_encoder = self.init_hidden_encoder(len(batch))
# pack data into a batch
data, labels, _ = data_manager.batch_sequence(batch, self.device)
data = self.embedding_encoder(data)
data = self.drop(data)
# encode
encoder_output, hidden_encoder = self.gru_encoder(data, hidden_encoder)
# set first token passed to decoder as tagset_size, mapped to the last row of the embedding
decoder_input = torch.zeros(len(batch), 1).long()
torch.add(decoder_input, self.tagset_size,
decoder_input) # special start character
decoder_input = decoder_input.to(self.device)
# encoder will pass its hidden state to the decoder
if self.bidirectional: # needs to be reshaped since a bidirectional layer will return (2, batch, hidden dim//2)
hidden_decoder = torch.cat((hidden_encoder[0], hidden_encoder[1]),
dim=1).unsqueeze(0)
else:
hidden_decoder = hidden_encoder
# decode and output 1 word at a time
results = []
for di in range(encoder_output.size()
[1]): # max length of any phrase in the batch
decoder_output, hidden_decoder = self.decoder_forward(
decoder_input, hidden_decoder)
_, topi = decoder_output.topk(1) # extract predicted label
decoder_input = topi.squeeze(1).detach().to(
self.device) # detach from history as input
results.append(decoder_output)
results = torch.cat(results, dim=1)
return results.view(-1, self.tagset_size), labels.view(-1)
def forward(self, batch):
# pre-elaborate hidden state
sequence = self.prepare_batch(batch)
embedded = self.embedding(sequence).view(sequence.size()[0], -1)
hidden = self.fc(embedded).unsqueeze(0)
if self.bidirectional:
hidden = hidden.view(2, hidden.size()[1], -1)
# output scores for each input embedding, use the pre-elaborated hidden state
data, labels, char_data = data_manager.batch_sequence(
batch, self.device)
data = self.embedding(data)
data = self.drop(data)
rec_out, hidden = self.recurrent(data, hidden)
# from output of the recurrent layer to a fc layer to map to tag space
tag_space = self.to_tag_space(rec_out.unsqueeze(1).contiguous())
tag_scores = torch.nn.functional.log_softmax(tag_space, dim=3)
return tag_scores.view(-1, self.tagset_size), labels.view(-1)
def forward(self, batch):
data, labels, char_data = data_manager.batch_sequence(
batch, self.device)
lengths = self.get_lengths(labels)
# get features and do predictions maximizing the sentence score using the crf
feats = self.get_features_from_recurrent(data, char_data, lengths)
scores, predictions = self.crf.viterbi_decode(feats, lengths)
# pad predictions so that they match in length with padded labels
batch_size, pad_to = labels.size()
_, pad_from = predictions.size()
padding = torch.zeros(batch_size,
pad_to - pad_from).long().to(self.device)
predictions = torch.cat([predictions, padding], dim=1)
predictions = predictions.expand(*labels.size())
# remove start and stop tags if there are any (mostly for safety, should not happen)
predictions[predictions == 43] = 0
predictions[predictions == 44] = 0
return predictions.view(-1), labels.view(-1)
def neg_log_likelihood(self, batch):
"""
Used for training, returns a loss that depends on the difference between the score that the model
would give to the sentence annd the score it would give to the correct labeling of the sentence.
:param batch:
:return:Pytorch loss.
"""
data, labels, char_data = data_manager.batch_sequence(
batch, self.device)
lengths = self.get_lengths(labels)
labels = self.get_labels(labels)
# get feats (scores for each label, for each word) from recurrent
feats = self.get_features_from_recurrent(data, char_data, lengths)
# get score of sentence from crf
norm_score = self.crf(feats, lengths)
# get score that the model would give to the correct labels
sequence_score = self.score(feats, labels, lengths)
loglik = sequence_score - norm_score
loglik = -loglik.mean()
return loglik
def forward(self, batch):
"""
Forward pass given data.
:param batch: List of samples containing data as transformed by the init transformer of this class.
:return: A (batch of) vectors of length equal to tagset, scoring each possible class for each word in a sentence,
for all sentences; a tensor containing the true label for each word and a tensor containing the lengths
of the sequences in descending order.
"""
sentence_as_matrix = self.prepare_batch(batch)
embedded = self.embedding(sentence_as_matrix)
embedded = self.drop(embedded)
# convolution on data
n1 = self.ngram1(embedded)
n2 = self.ngram2(embedded)
n3 = self.ngram3(embedded)
# combine result in a vector that will be the initial hidden state of the recurrent layer
batch_size = embedded.size()[0]
n1 = n1.view(batch_size, -1)
n2 = n2.view(batch_size, -1)
n3 = n3.view(batch_size, -1)
hidden = torch.cat((n1, n2, n3), dim=1).unsqueeze(0)
if self.bidirectional:
hidden = hidden.view(2, hidden.size()[1], -1)
data, labels, _ = data_manager.batch_sequence(batch, self.device)
data = self.embedding(data)
data = self.drop(data)
lstm_out, hidden = self.lstm(data, hidden)
# send output to fc layer(s)
tag_space = self.to_tag_space(lstm_out.unsqueeze(1).contiguous())
tag_scores = torch.nn.functional.log_softmax(tag_space, dim=3)
return tag_scores.view(-1, self.tagset_size), labels.view(-1)
