def __init__(self, data, FLAGS):
super(Model, self).__init__(data, FLAGS)
encoder_embedding_size = 16
encoder_lstm_size = 16
encoder_vocabulary_length = len(data.idx2word_history)
encoder_sequence_length = data.train_set['histories'].shape[2]
history_length = data.train_set['histories'].shape[1]
action_templates_vocabulary_length = len(data.idx2word_action_template)
with tf.name_scope('data'):
batch_histories = tf.Variable(data.batch_histories, name='histories', trainable=False)
batch_actions_template = tf.Variable(data.batch_actions_template, name='actions',
trainable=False)
histories = tf.gather(batch_histories, self.batch_idx)
actions_template = tf.gather(batch_actions_template, self.batch_idx)
with tf.name_scope('model'):
with tf.variable_scope("batch_size"):
batch_size = tf.shape(histories)[0]
encoder_embedding = embedding(
input=histories,
length=encoder_vocabulary_length,
size=encoder_embedding_size,
name='encoder_embedding'
)
with tf.name_scope("UtterancesEncoder"):
with tf.name_scope("RNNForwardUtteranceEncoderCell_1"):
cell_fw_1 = LSTMCell(
num_units=encoder_lstm_size,
input_size=encoder_embedding_size,
use_peepholes=True
)
initial_state_fw_1 = cell_fw_1.zero_state(batch_size, tf.float32)
with tf.name_scope("RNNBackwardUtteranceEncoderCell_1"):
cell_bw_1 = LSTMCell(
num_units=encoder_lstm_size,
input_size=encoder_embedding_size,
use_peepholes=True
)
initial_state_bw_1 = cell_bw_1.zero_state(batch_size, tf.float32)
with tf.name_scope("RNNForwardUtteranceEncoderCell_2"):
cell_fw_2 = LSTMCell(
num_units=encoder_lstm_size,
input_size=cell_fw_1.output_size + cell_bw_1.output_size,
use_peepholes=True
)
initial_state_fw_2 = cell_fw_2.zero_state(batch_size, tf.float32)
# the input data has this dimensions
# [
# #batch,
# #utterance in a history (a dialogue),
# #word in an utterance (a sentence),
# embedding dimension
# ]
# encode all utterances along the word axis
encoder_states_2d = []
for utterance in range(history_length):
encoder_outputs, _ = brnn(
cell_fw=cell_fw_1,
cell_bw=cell_bw_1,
inputs=[encoder_embedding[:, utterance, word, :] for word in
range(encoder_sequence_length)],
initial_state_fw=initial_state_fw_1,
initial_state_bw=initial_state_bw_1,
name='RNNUtteranceBidirectionalLayer',
reuse=True if utterance > 0 else None
)
_, encoder_states = rnn(
cell=cell_fw_2,
inputs=encoder_outputs,
initial_state=initial_state_fw_2,
name='RNNUtteranceForwardEncoder',
reuse=True if utterance > 0 else None
)
# print(encoder_states[-1])
encoder_states = tf.concat(1, tf.expand_dims(encoder_states[-1], 1))
# print(encoder_states)
encoder_states_2d.append(encoder_states)
encoder_states_2d = tf.concat(1, encoder_states_2d)
# print('encoder_states_2d', encoder_states_2d)
with tf.name_scope("HistoryEncoder"):
# encode all histories along the utterance axis
with tf.name_scope("RNNForwardHistoryEncoderCell_1"):
cell_fw_1 = LSTMCell(
num_units=encoder_lstm_size,
input_size=cell_fw_2.state_size,
use_peepholes=True
)
initial_state_fw_1 = cell_fw_1.zero_state(batch_size, tf.float32)
with tf.name_scope("RNNBackwardHistoryEncoderCell_1"):
cell_bw_1 = LSTMCell(
num_units=encoder_lstm_size,
input_size=cell_fw_2.state_size,
use_peepholes=True
)
initial_state_bw_1 = cell_fw_2.zero_state(batch_size, tf.float32)
with tf.name_scope("RNNForwardHistoryEncoderCell_2"):
cell_fw_2 = LSTMCell(
num_units=encoder_lstm_size,
input_size=cell_fw_1.output_size + cell_bw_1.output_size,
use_peepholes=True
)
initial_state_fw_2 = cell_fw_2.zero_state(batch_size, tf.float32)
encoder_outputs, _ = brnn(
cell_fw=cell_fw_1,
cell_bw=cell_bw_1,
inputs=[encoder_states_2d[:, utterance, :] for utterance in range(history_length)],
initial_state_fw=initial_state_fw_1,
initial_state_bw=initial_state_bw_1,
name='RNNHistoryBidirectionalLayer',
reuse=None
)
_, encoder_states = rnn(
cell=cell_fw_2,
inputs=encoder_outputs,
initial_state=initial_state_fw_2,
name='RNNHistoryForwardEncoder',
reuse=None
)
with tf.name_scope("Decoder"):
linear_size = cell_fw_2.state_size
# decode all histories along the utterance axis
activation = tf.nn.relu(encoder_states[-1])
activation = tf.nn.dropout(activation, self.dropout_keep_prob)
projection = linear(
input=activation,
input_size=linear_size,
output_size=linear_size,
name='linear_projection_1'
)
activation = tf.nn.relu(projection)
activation = tf.nn.dropout(activation, self.dropout_keep_prob)
projection = linear(
input=activation,
input_size=linear_size,
output_size=linear_size,
name='linear_projection_2'
)
activation = tf.nn.relu(projection)
activation = tf.nn.dropout(activation, self.dropout_keep_prob)
projection = linear(
input=activation,
input_size=linear_size,
output_size=action_templates_vocabulary_length,
name='linear_projection_3'
)
self.predictions = tf.nn.softmax(projection, name="softmax_output")
# print(self.predictions)
if FLAGS.print_variables:
for v in tf.trainable_variables():
print(v.name)
with tf.name_scope('loss'):
one_hot_labels = dense_to_one_hot(actions_template, action_templates_vocabulary_length)
self.loss = tf.reduce_mean(- one_hot_labels * tf.log(tf.clip_by_value(self.predictions, 1e-10, 1.0)), name='loss')
tf.scalar_summary('loss', self.loss)
with tf.name_scope('accuracy'):
correct_prediction = tf.equal(tf.argmax(one_hot_labels, 1), tf.argmax(self.predictions, 1))
self.accuracy = tf.reduce_mean(tf.cast(correct_prediction, 'float'))
tf.scalar_summary('accuracy', self.accuracy)
