def extract_args(self, features, mode, params):
super().extract_args(features, mode, params)
if self.hparams.vocab_size > 0:
self.vocab = Vocabulary(size=self.hparams.vocab_size)
else:
self.vocab = Vocabulary(
fname=self.hparams.vocab_file,
skip_tokens=self.hparams.skip_tokens,
skip_tokens_start=self.hparams.skip_tokens_start)
def main(_):
print("Loading hyperparameters..")
params = util.load_params(FLAGS.params_file)
print("Building model..")
model_dir = FLAGS.model_dir
if FLAGS.clean_model_dir:
util.clean_model_dir(model_dir)
if FLAGS.model_cls == "transformer":
model_cls = TransformerEstimator
elif FLAGS.model_cls == "seq2seq":
model_cls = Seq2SeqEstimator
else:
raise ValueError("Model class not supported.")
model = model_cls(model_dir, params)
print("Getting sources..")
fields = {"train/inputs": "int", "train/targets": "int"}
train_source = DataSource(FLAGS.train_file, fields)
test_source = DataSource(FLAGS.test_file, fields)
field_map = {"inputs": "train/inputs", "targets": "train/targets"}
train_input_fn = train_source.get_input_fn(
"train_in", field_map, None, FLAGS.batch_size)
test_input_fn = test_source.get_input_fn(
"test_in", field_map, 1, FLAGS.batch_size)
print("Processing model..")
model.train(train_input_fn, steps=FLAGS.train_batches)
model.evaluate(test_input_fn)
if FLAGS.interactive:
print("Interactive decoding...")
vocab = Vocabulary(fname=params["vocab_file"])
decoding.cmd_decode(model, vocab)
def extract_args(self, features, mode, params):
super().extract_args(features, mode, params)
self.d_k = self.hparams.d_model // self.hparams.num_heads
self.d_pos = self.hparams.d_pos if self.hparams.d_pos == 0 else self.hparams.d_pos
self.d_ff = self.hparams.d_ff if self.hparams.d_ff == 0 else self.hparams.d_ff
if self.hparams.vocab_size > 0:
self.vocab = Vocabulary(size=self.hparams.vocab_size)
else:
self.vocab = Vocabulary(fname=self.hparams.vocab_file)
if not self.hparams.fixed_learning_rate:
self.train_step = tf.get_variable(
'train_step',
shape=[],
dtype=tf.float32,
initializer=tf.zeros_initializer(dtype=tf.int32),
trainable=False)
self.learning_rate = ( # magic formula provided in transformer paper
tf.sqrt(1.0 / self.hparams.d_model) * tf.minimum(
self.train_step * tf.pow(self.hparams.warmup_steps, -1.5),
tf.pow(self.train_step, -0.5)))
def write_to_tfrecord(self, out_file, pipeline=None, max_lines=None):
print("Writing to TFRecord..")
writer = tf.python_io.TFRecordWriter(out_file)
line_ctr = 0
for row in self.row_gen():
if not self.process_row(pipeline, row):
continue
feature = dict()
for i in range(len(row)):
key_ = self.headers[i].name
type_ = self.headers[i].data_type
vocab_ = self.headers[i].vocab_file
mode_ = self.headers[i].vocab_mode
if type_ == "text":
if vocab_ not in self.vocabs:
if mode_ != "write":
self.vocabs[vocab_] = Vocabulary(fname=vocab_)
else:
self.vocabs[vocab_] = Vocabulary()
row[i] = self.vocabs[vocab_].tokenize(
row[i], fixed_vocab=(mode_ == "read"))
feature[key_] = self.int64_feature(row[i])
elif type_ == "int":
print([int(row[i])])
feature[key_] = self.int64_feature([int(row[i])])
elif type_ == "float":
feature[key_] = self.float_feature([float(row[i])])
else:
raise ValueError("Header type " + str(type_) +
" not supported.")
example = tf.train.Example(features=tf.train.Features(
feature=feature))
writer.write(example.SerializeToString())
line_ctr = self.print_lines_processed(line_ctr)
if max_lines is not None and line_ctr >= max_lines:
break
writer.close()
def build_vocab_files(self, count_cutoff=0):
print("Building vocabularies..")
read_only = True
self.vocabs = dict()
for i in range(len(self.headers)):
vocab_ = self.headers[i].vocab_file
mode = self.headers[i].vocab_mode
if ((vocab_ is not None) and (vocab_ not in self.vocabs)
and (mode != "read")):
read_only = False
if mode == "write":
self.vocabs[vocab_] = Vocabulary()
elif mode == "append":
self.vocabs[vocab_] = Vocabulary(fname=vocab_)
else:
raise ValueError("Vocab mode " + str(mode) +
" not supported.")
elif vocab_ is not None and mode == "read":
self.vocabs[vocab_] = Vocabulary(fname=vocab_)
if read_only:
return
line_ctr = 0
for row in self.row_gen():
for i in range(len(row)):
vocab_ = self.headers[i].vocab_file
if vocab_ in self.vocabs:
self.vocabs[vocab_].tokenize(row[i], fixed_vocab=False)
line_ctr = self.print_lines_processed(line_ctr)
for vocab_ in self.vocabs:
if count_cutoff >= 0:
self.vocabs[vocab_].count_cutoff(count_cutoff)
with open(vocab_, "w", encoding="utf8") as vocab_f:
for word in self.vocabs[vocab_].words:
vocab_f.write(word + "\n")
for i in range(len(self.headers)):
self.headers[i].vocab_mode = "read"
def extract_args(self, features, mode, params):
super().extract_args(features, mode, params)
if (self.hparams.src_vocab_size == 0
and self.hparams.tgt_vocab_size == 0
and self.hparams.src_vocab_file == ""
and self.hparams.tgt_vocab_file == ""):
self.src_vocab = self.vocab
self.tgt_vocab = self.vocab
else:
if self.hparams.src_vocab_size > 0:
self.src_vocab = Vocabulary(size=self.hparams.src_vocab_size)
else:
self.src_vocab = Vocabulary(fname=self.hparams.src_vocab_file)
if self.hparams.tgt_vocab_size > 0:
self.tgt_vocab = Vocabulary(size=self.hparams.tgt_vocab_size)
else:
self.tgt_vocab = Vocabulary(fname=self.hparams.tgt_vocab_file)
def main(_):
print("Loading hyperparameters..")
params = util.load_params(FLAGS.params_file)
print("Building model..")
validation_config = tf.estimator.RunConfig(
save_checkpoints_steps=100,
keep_checkpoint_max=None,
)
model_dir = FLAGS.model_dir
if FLAGS.clean_model_dir:
util.clean_model_dir(model_dir)
if FLAGS.model_cls == "transformer":
model_cls = TransformerEstimator
elif FLAGS.model_cls == "seq2seq":
model_cls = Seq2SeqEstimator
else:
raise ValueError("Model class not supported.")
model = model_cls(model_dir, params, config=validation_config)
print("Getting sources..")
fields = {"train/inputs": "int", "train/targets": "int"}
train_source = DataSource(FLAGS.train_file, fields)
test_source = DataSource(FLAGS.test_file, fields)
field_map = {"inputs": "train/inputs", "targets": "train/targets"}
train_input_fn = train_source.get_input_fn("train_in", field_map, None,
FLAGS.batch_size)
test_input_fn = test_source.get_input_fn("test_in", field_map, 1,
FLAGS.batch_size)
print("Processing model..")
model.train(train_input_fn, steps=FLAGS.train_batches)
model.choose_best_checkpoint(test_input_fn)
model.evaluate(test_input_fn)
if FLAGS.interaction != "off":
print("Interactive decoding...")
vocab = Vocabulary(fname=params["vocab_file"])
if FLAGS.interaction == "cmd":
decoding.cmd_decode(model, vocab, persona=True)
elif FLAGS.interaction == "gui":
decoding.gui_decode(model, vocab)
def write_to_tfrecord(self,
out_file,
pipeline=None,
max_lines=None,
line_gen=None,
line_shard_len=None,
streamline=True,
traversal="depth_first",
max_pos_len=32):
print("Writing to TFRecord..")
writer = tf.python_io.TFRecordWriter(out_file)
line_ctr = 0
if line_gen is None:
line_gen = self.row_gen()
for row in line_gen:
if not self.process_row(row, pipeline):
continue
feature = {}
for i in range(len(row)):
key_ = self.headers[i].name
type_ = self.headers[i].data_type
vocab_ = self.headers[i].vocab_file
mode_ = self.headers[i].vocab_mode
if type_ == "text" or type_ == "tree":
if vocab_ not in self.vocabs:
if mode_ != "write":
self.vocabs[vocab_] = Vocabulary(fname=vocab_)
else:
self.vocabs[vocab_] = Vocabulary()
if type_ == "text":
row[i] = self.vocabs[vocab_].tokenize(
row[i], fixed_vocab=(mode_ == "read"))
feature[key_] = self.int64_feature(row[i])
else:
tree_ints = []
tree_pos = []
for node in row[i].choose_traversal(traversal):
if streamline:
if node.value == "_NULL" and (
not node.parent
or node.parent.children[0].value
== "_NULL"):
continue
node.value = str(node.value)
if (not node.is_leaf()
) and node.children[0].value == "_NULL":
if node.children[1].value == "_NULL":
node.value = str(node.value) + "_0"
else:
node.value = str(node.value) + "_1"
if mode_ == "read" and node.value not in self.vocabs[
vocab_].word2idx:
if len(node.value
) > 2 and node.value[-2:] == "_0":
node.value = "_UNK_0"
elif len(node.value
) > 2 and node.value[-2:] == "_1":
node.value = "_UNK_1"
else:
node.value = "_UNK"
tree_ints.append(self.vocabs[vocab_].get_token_id(
node.value, mode_ == "read"))
tree_pos += node.get_padded_positional_encoding(
max_pos_len)
field = self.headers[i].name
feature[field] = self.int64_feature(tree_ints)
feature[field + "_pos"] = self.float_feature(tree_pos)
elif type_ == "int":
feature[key_] = self.int64_feature([int(row[i])])
elif type_ == "float":
feature[key_] = self.float_feature([float(row[i])])
else:
raise ValueError("Header type " + str(type_) +
" not supported.")
example = tf.train.Example(features=tf.train.Features(
feature=feature))
writer.write(example.SerializeToString())
line_ctr = self.print_lines_processed(line_ctr, "trees")
if max_lines is not None and line_ctr >= max_lines:
break
writer.close()
def apply_byte_pair_encodings(self, out_file, max_lines=None):
self.build_vocab_files()
print("Applying byte pair encodings..")
all_bpe_vocabs = dict()
word_encodings = dict()
for vocab_ in self.vocabs:
all_bpe_vocabs[vocab_] = Vocabulary(fname=vocab_)
word_encodings[vocab_] = dict()
length_headers = OrderedDict()
for i in range(len(self.headers)):
if self.headers[i].vocab_file is not None:
length_headers[self.headers[i].name] = DataHeader(
self.headers[i].name + "/_length", "int")
for header_name in length_headers:
self.headers.append(length_headers[header_name])
with open(out_file, "w", encoding="utf8") as out_f:
line_ctr = 0
for row in self.row_gen():
row_extension = []
for i in range(len(row)):
vocab_ = self.headers[i].vocab_file
if vocab_ is not None:
row_extension.append(len(row[i].strip().split()))
new_elem = ""
for word in row[i].strip().split():
if word in word_encodings[vocab_]:
encoding = word_encodings[vocab_][word]
else:
encoding = list(word) + ["</EOW>"]
bigrams = dict()
for j in range(len(encoding) - 1):
bigram = encoding[j] + encoding[j + 1]
if bigram in all_bpe_vocabs[
vocab_].word2idx:
bigrams[j] = all_bpe_vocabs[
vocab_].word2idx[bigram]
while len(bigrams) > 0:
bigrams_argmin = None
for idx in bigrams:
if bigrams_argmin is None or bigrams[
idx] < bigrams[bigrams_argmin]:
bigrams_argmin = idx
encoding = encoding[0:bigrams_argmin] + \
[encoding[bigrams_argmin] + encoding[bigrams_argmin+1]] + encoding[bigrams_argmin+2:]
bigrams = dict()
for j in range(len(encoding) - 1):
bigram = encoding[j] + encoding[j + 1]
if bigram in all_bpe_vocabs[
vocab_].word2idx:
bigrams[j] = all_bpe_vocabs[
vocab_].word2idx[bigram]
word_encodings[vocab_][word] = encoding
for subword in encoding:
new_elem += subword + " "
row[i] = new_elem
row += row_extension
out_f.write(self.concatenate_segments(row))
line_ctr = self.print_lines_processed(line_ctr)
if max_lines is not None and line_ctr >= max_lines:
break
self.in_files = [out_file]
def main(_):
print("Loading parameters..")
params = util.load_params(FLAGS.params_file)
print("Building model..")
model_dir = FLAGS.model_dir
if FLAGS.clean_model_dir:
util.clean_model_dir(model_dir)
first_model = PersonaSeq2SeqEstimator(model_dir, params, scope="first")
second_model_encoder = Seq2SeqEncoderEstimator(model_dir,
params,
scope="second_encoder")
second_model = EstimatorChain([second_model_encoder, first_model.decoder],
model_dir,
params,
scope="second")
mmi_model = PersonaSeq2SeqEstimator(model_dir,
params,
scope="mmi",
is_mmi_model=True)
model_group = EstimatorGroup([first_model, second_model, mmi_model],
model_dir,
params,
scope="group")
print("Getting sources..")
fields = {
"train/inputs": "int",
"train/targets": "int",
"train/speakers": "int"
}
train_source = DataSource(FLAGS.train_file, fields)
autoenc_source = DataSource(FLAGS.autoenc_file, fields)
test_source = DataSource(FLAGS.test_file, fields)
train_field_map = {
"inputs": "train/inputs",
"targets": "train/targets",
"speaker_ids": "train/speakers"
}
autoenc_field_map = {
"inputs": "train/inputs",
"targets": "train/inputs",
"speaker_ids": "train/speakers"
}
mmi_field_map = {
"inputs": "train/targets",
"targets": "train/inputs",
"speaker_ids": "train/speakers"
}
paired_input_fn = train_source.get_input_fn("paired_in", train_field_map,
None, FLAGS.batch_size)
autoenc_input_fn = train_source.get_input_fn("autoenc_in",
autoenc_field_map, None,
FLAGS.batch_size)
mmi_input_fn = train_source.get_input_fn("mmi_in", mmi_field_map, None,
FLAGS.batch_size)
train_input_fn = DataSource.group_input_fns(
["first", "second", "mmi"],
[paired_input_fn, autoenc_input_fn, mmi_input_fn])
test_input_fn = test_source.get_input_fn("test_in", train_field_map, 1,
FLAGS.batch_size)
print("Processing models..")
print("Pretraining primary model..")
model_group.train(train_input_fn,
first_model,
steps=FLAGS.pretrain_batches)
print("Multitask training..")
model_group.train(train_input_fn, {
"first": 1,
"second": 1,
"mmi": 0
},
steps=FLAGS.train_batches)
print("Training MMI model..")
model_group.train(train_input_fn, mmi_model, steps=FLAGS.mmi_batches)
print("Evaluating..")
model_group.evaluate(test_input_fn, first_model)
if FLAGS.interactive:
print("Interactive decoding...")
vocab = Vocabulary(fname=params["vocab_file"])
decoding.cmd_decode(first_model,
vocab,
persona=True,
mmi_component=mmi_model)
class AbstractTransformerEstimator(AbstractIcecapsEstimator):
@classmethod
def construct_expected_params(cls):
expected_params = super().construct_expected_params()
expected_params["vocab_file"] = cls.make_param(
"icecaps/examples/dummy_data/vocab.dic")
expected_params["vocab_size"] = cls.make_param(0)
expected_params["depth"] = cls.make_param(1)
expected_params["num_heads"] = cls.make_param(8)
expected_params["d_model"] = cls.make_param(32)
expected_params["d_pos"] = cls.make_param(32)
expected_params["d_ff"] = cls.make_param(64)
expected_params["max_length"] = cls.make_param(10)
expected_params["min_wavelength"] = cls.make_param(1.0)
expected_params["max_wavelength"] = cls.make_param(1000.0)
expected_params["warmup_steps"] = cls.make_param(4000.0)
expected_params["fixed_learning_rate"] = cls.make_param(False)
expected_params["learn_wavelengths"] = cls.make_param(False)
expected_params["modality"] = cls.make_param("seq")
expected_params["tree_depth"] = cls.make_param(256)
expected_params["tree_width"] = cls.make_param(2)
expected_params["learn_positional_embeddings"] = cls.make_param(False)
return expected_params
def extract_args(self, features, mode, params):
super().extract_args(features, mode, params)
self.d_k = self.hparams.d_model // self.hparams.num_heads
self.d_pos = self.hparams.d_pos if self.hparams.d_pos == 0 else self.hparams.d_pos
self.d_ff = self.hparams.d_ff if self.hparams.d_ff == 0 else self.hparams.d_ff
if self.hparams.vocab_size > 0:
self.vocab = Vocabulary(size=self.hparams.vocab_size)
else:
self.vocab = Vocabulary(fname=self.hparams.vocab_file)
if not self.hparams.fixed_learning_rate:
self.train_step = tf.get_variable(
'train_step',
shape=[],
dtype=tf.float32,
initializer=tf.zeros_initializer(dtype=tf.int32),
trainable=False)
self.learning_rate = ( # magic formula provided in transformer paper
tf.sqrt(1.0 / self.hparams.d_model) * tf.minimum(
self.train_step * tf.pow(self.hparams.warmup_steps, -1.5),
tf.pow(self.train_step, -0.5)))
def build_embeddings(self):
# self.hparams.max_length), dtype=tf.float32), 1)
position = tf.expand_dims(tf.cast(tf.range(0, 2048), dtype=tf.float32),
1)
if self.hparams.learn_wavelengths:
wavelength_logs = tf.get_variable("wavelength_logs",
[self.d_pos // 2], tf.float32)
else:
wavelength_logs = tf.linspace(
math.log(self.hparams.min_wavelength),
math.log(self.hparams.max_wavelength), self.d_pos // 2)
div_term = tf.expand_dims(tf.exp(-wavelength_logs), 0)
outer_product = tf.matmul(position, div_term)
cosines = tf.cos(outer_product)
sines = tf.sin(outer_product)
self.positional_embeddings = tf.concat([cosines, sines], -1)
if self.hparams.learn_positional_embeddings:
self.positional_embeddings = tf.get_variable(
name='positional_embeddings',
shape=[self.hparams.max_length, self.hparams.d_model
]) * np.sqrt(float(self.hparams.d_model))
self.token_embeddings = tf.get_variable(
name='token_embeddings',
shape=[self.vocab.size(), self.hparams.d_model]) * np.sqrt(
float(self.hparams.d_model))
if self.hparams.modality == "tree":
self.d_tree_param = self.d_pos // (self.hparams.tree_depth *
self.hparams.tree_width)
self.tree_params = tf.tanh(
tf.get_variable("tree_params", [self.d_tree_param]))
self.tiled_tree_params = tf.tile(
tf.reshape(self.tree_params, [1, 1, -1]),
[self.hparams.tree_depth, self.hparams.tree_width, 1])
self.tiled_depths = tf.tile(
tf.reshape(tf.range(self.hparams.tree_depth, dtype=tf.float32),
[-1, 1, 1]),
[1, self.hparams.tree_width, self.d_tree_param])
self.tree_norm = tf.sqrt(
(1 - tf.square(self.tree_params)) * self.hparams.d_model / 2)
self.tree_weights = tf.reshape(
tf.pow(self.tiled_tree_params, self.tiled_depths) *
self.tree_norm, [
self.hparams.tree_depth * self.hparams.tree_width,
self.d_tree_param
])
def treeify_positions(self, positions):
treeified = tf.expand_dims(positions, -1) * self.tree_weights
shape = tf.shape(treeified)
shape = tf.concat([shape[:-2], [self.d_pos]], -1)
treeified = tf.reshape(treeified, shape)
return treeified
def init_inputs(self):
self.inputs_sparse = tf.cast(self.features["inputs"], tf.int32)
self.mask = tf.cast(
tf.not_equal(self.inputs_sparse, self.vocab.end_token_id),
tf.float32)
self.inputs_length = tf.cast(tf.count_nonzero(self.mask, -1), tf.int32)
self.inputs_max_length = tf.reduce_max(self.inputs_length)
self.batch_size = tf.shape(self.inputs_sparse)[0]
self.inputs_sparse = tf.slice(
self.inputs_sparse, [0, 0],
[self.batch_size, self.inputs_max_length])
self.mask = tf.slice(self.mask, [0, 0],
[self.batch_size, self.inputs_max_length])
self.inputs_dense = tf.nn.embedding_lookup(
params=self.token_embeddings, ids=self.inputs_sparse)
if self.hparams.modality == "seq":
self.positions = tf.slice(self.positional_embeddings, [0, 0],
[self.inputs_max_length, self.d_pos])
elif self.hparams.modality == "tree":
self.positions = tf.reshape(self.features["inputs_positions"], [
self.batch_size, self.inputs_max_length,
self.hparams.tree_depth * self.hparams.tree_width
])
self.positions = self.treeify_positions(self.positions)
else:
raise ValueError("This input modality is not supported.")
if self.d_pos != self.hparams.d_model:
self.positions = tf.layers.dense(self.positions,
self.hparams.d_model)
self.inputs_dense = self.inputs_dense + self.positions
self.inputs_dense = tf.nn.dropout(self.inputs_dense, self.keep_prob)
self.inputs_dense = tf.transpose(
tf.transpose(self.inputs_dense) * tf.transpose(self.mask))
def build_layer_norm(self, x):
return tf.contrib.layers.layer_norm(x, begin_norm_axis=-1)
def build_sublayer_fn(self, x, f):
x = self.build_layer_norm(x)
x = x + tf.nn.dropout(f(x), self.keep_prob)
return x
def attention(self, query, key, value, d_k, enc_mask=None, dec_mask=None):
scores = tf.matmul(query, tf.transpose(key,
[0, 1, 3, 2])) / math.sqrt(d_k)
if enc_mask is not None:
scores = tf.transpose(
scores, [1, 2, 0, 3]) * enc_mask - 1e24 * (1.0 - enc_mask)
scores = tf.transpose(scores, [2, 0, 1, 3])
if dec_mask is not None:
scores = scores * dec_mask - 1e24 * (1.0 - dec_mask)
p_attn = tf.nn.softmax(scores)
p_attn = tf.nn.dropout(p_attn, keep_prob=self.keep_prob)
attended_values = tf.matmul(p_attn, value)
return attended_values, p_attn
def mha_fn(self, query, key, value, batch_size, enc_mask_, dec_mask_):
with tf.variable_scope("mha", reuse=tf.AUTO_REUSE) as scope:
query = tf.transpose(
tf.reshape(
tf.layers.dense(query, self.hparams.d_model,
use_bias=True),
[batch_size, -1, self.hparams.num_heads, self.d_k]),
[0, 2, 1, 3])
key = tf.transpose(
tf.reshape(
tf.layers.dense(key, self.hparams.d_model, use_bias=True),
[batch_size, -1, self.hparams.num_heads, self.d_k]),
[0, 2, 1, 3])
value = tf.transpose(
tf.reshape(
tf.layers.dense(value, self.hparams.d_model,
use_bias=True),
[batch_size, -1, self.hparams.num_heads, self.d_k]),
[0, 2, 1, 3])
attended, _ = self.attention(query, key, value, self.d_k,
enc_mask_, dec_mask_)
attended = tf.reshape(tf.transpose(attended, [0, 2, 1, 3]),
[batch_size, -1, self.hparams.d_model])
return attended
def build_mha_sublayer(self,
x,
m,
batch_size,
enc_mask=None,
dec_mask=None):
with tf.variable_scope("attn", reuse=tf.AUTO_REUSE) as scope:
return self.build_sublayer_fn(
x, lambda q: tf.layers.dense(
self.mha_fn(q, m, m, batch_size, enc_mask, dec_mask), self.
hparams.d_model))
def build_ffn_sublayer(self, x, d_ff):
with tf.variable_scope("ffn", reuse=tf.AUTO_REUSE) as scope:
def ffn_fn(q):
return tf.layers.dense(tf.layers.dense(q, d_ff, tf.nn.relu),
self.hparams.d_model)
return self.build_sublayer_fn(x, ffn_fn)
def build_optimizer(self, trainable_params=None):
super().build_optimizer(trainable_params)
self.step_update_op = tf.assign_add(self.train_step, 1.0)
with tf.control_dependencies([self.step_update_op]):
self.train_op = tf.group([self.step_update_op, self.train_op])
def __init__(self, fname, fields, vocab=None):
self.fname = fname
self.parse_fields(fields)
self.input_fns = dict()
self.vocab = vocab if vocab is not None else Vocabulary()
class AbstractRecurrentEstimator(AbstractIcecapsEstimator):
@classmethod
def construct_expected_params(cls):
expected_params = super().construct_expected_params()
expected_params["max_length"] = cls.make_param(50)
expected_params["cell_type"] = cls.make_param('gru')
expected_params["hidden_units"] = cls.make_param(32)
expected_params["depth"] = cls.make_param(1)
expected_params["token_embed_dim"] = cls.make_param(16)
expected_params["tie_token_embeddings"] = cls.make_param(True)
expected_params["beam_width"] = cls.make_param(8)
expected_params["vocab_file"] = cls.make_param(
"./dummy_data/vocab.dic")
expected_params["vocab_size"] = cls.make_param(0)
expected_params["skip_tokens"] = cls.make_param('')
expected_params["skip_tokens_start"] = cls.make_param('')
return expected_params
def extract_args(self, features, mode, params):
super().extract_args(features, mode, params)
if self.hparams.vocab_size > 0:
self.vocab = Vocabulary(size=self.hparams.vocab_size)
else:
self.vocab = Vocabulary(
fname=self.hparams.vocab_file,
skip_tokens=self.hparams.skip_tokens,
skip_tokens_start=self.hparams.skip_tokens_start)
def build_cell(self, name=None):
if self.hparams.cell_type == 'linear':
cell = BasicRNNCell(self.hparams.hidden_units,
activation=tf.identity,
name=name)
elif self.hparams.cell_type == 'tanh':
cell = BasicRNNCell(self.hparams.hidden_units,
activation=tf.tanh,
name=name)
elif self.hparams.cell_type == 'relu':
cell = BasicRNNCell(self.hparams.hidden_units,
activation=tf.nn.relu,
name=name)
elif self.hparams.cell_type == 'gru':
cell = GRUCell(self.hparams.hidden_units, name=name)
elif self.hparams.cell_type == 'lstm':
cell = LSTMCell(self.hparams.hidden_units, name=name)
else:
raise ValueError('Provided cell type not supported.')
return cell
def build_deep_cell(self,
cell_list=None,
name=None,
return_raw_list=False):
if name is None:
name = "cell"
if cell_list is None:
cell_list = []
for i in range(self.hparams.depth):
cell = self.build_cell(name=name + "_" + str(i))
cell = DropoutWrapper(cell, output_keep_prob=self.keep_prob)
cell_list.append(cell)
if return_raw_list:
return cell_list
if len(cell_list) == 1:
return cell_list[0]
return MultiRNNCell(cell_list)
def build_rnn(self, input_key="inputs"):
with tf.variable_scope('rnn'):
self.cell = self.build_deep_cell()
self.build_inputs(input_key)
self.outputs, self.last_state = tf.nn.dynamic_rnn(
cell=self.cell,
inputs=self.inputs_dense,
sequence_length=self.inputs_length,
time_major=False,
dtype=tf.float32
) # [batch_size, max_time_step, cell_output_size], [batch_size, cell_output_size]
def build_embeddings(self):
if "token_embeddings" in self.features and self.hparams.tie_token_embeddings:
self.token_embeddings = self.features["token_embeddings"]
else:
self.token_embeddings = tf.get_variable(
name='token_embeddings',
shape=[self.vocab.size(), self.hparams.token_embed_dim])
if self.hparams.token_embed_dim != self.hparams.hidden_units:
projection = tf.get_variable(name='token_embed_proj',
shape=[
self.hparams.token_embed_dim,
self.hparams.hidden_units
])
self.token_embeddings = self.token_embeddings @ projection
def embed_sparse_to_dense(self, sparse):
with tf.variable_scope('embed_sparse_to_dense', reuse=tf.AUTO_REUSE):
dense = tf.nn.embedding_lookup(self.token_embeddings, sparse)
return dense
def build_inputs(self, input_key):
self.build_embeddings()
self.inputs_sparse_untrimmed = tf.cast(self.features[input_key],
tf.int32)
self.inputs_length = tf.cast(
tf.count_nonzero(
self.inputs_sparse_untrimmed - self.vocab.end_token_id, -1),
tf.int32)
self.inputs_max_length = tf.reduce_max(self.inputs_length)
self.inputs_sparse = tf.slice(self.inputs_sparse_untrimmed, [0, 0],
[-1, self.inputs_max_length])
self.inputs_dense = self.embed_sparse_to_dense(self.inputs_sparse)
self.batch_size = tf.shape(self.inputs_sparse)[0]
def build_loss(self):
with tf.name_scope('build_loss'):
self.loss = seq2seq.sequence_loss(
logits=self.logits,
targets=self.targets_sparse,
weights=self.target_mask,
average_across_timesteps=True,
average_across_batch=True,
)
self.reported_loss = tf.identity(self.loss, 'reported_loss')
def main(_):
'''
This is a simple example of how to build an Icecaps training script, and is essentially
the "Hello World" of Icecaps. Icecaps training scripts follow a basic five-phase pattern
that we describe here. We train a basic model on the paired data stored in
dummy_data/paired_personalized.tfrecord. For information on how to build TFRecords
from text data files, please see data_processing_example.py.
'''
print("Loading hyperparameters..")
# The first phase is to load hyperparameters from a .params file. These files follow a
# simple colon-delimited format (e.g. see dummy_params/simple_example_seq2seq.params).
params = util.load_params(FLAGS.params_file)
print("Building model..")
# Second, we build our architecture based on our loaded hyperparameters. Our architecture
# here is very basic: we use a simple LSTM-based seq2seq model. For information on more
# complex architectures, wee train_persona_mmi_example.py.
model_dir = FLAGS.model_dir
if FLAGS.clean_model_dir:
util.clean_model_dir(model_dir)
model_cls = Seq2SeqEstimator
# Every estimator expects a different set of hyperparmeters. If you set use_default_params
# to True in your .params file, the estimator will employ default values for any unspecified
# hyperparameters. To view the list of hyperparmeters with default values, you can run the
# class method list_params(). E.g. you can open a Python session and run
# Seq2SeqEstimator.list_params() to view what hyperparameters our seq2seq estimator expects.
model = model_cls(model_dir, params)
print("Getting sources..")
# Third, we set up our data sources. DataSource objects allow you to build input_fns that
# efficiently feed data into the training pipeline from TFRecord files. In our simple example,
# we set up two data sources: one for training and one for testing.
# TFRecords are created with name variables per data point. You must create a fields dictionary
# to tell the DataSource which variables to load and what their types are.
fields = {"train/inputs": "int", "train/targets": "int"}
train_source = DataSource(FLAGS.train_file, fields)
test_source = DataSource(FLAGS.test_file, fields)
# Then, you must create a field_map dictionary to tell your estimator how to map the TFRecord's
# variable names to the names expected by the estimator. While this may seem like unnecessary
# overhead in this simple example, it provides useful flexibility in more complex scenarios.
field_map = {"inputs": "train/inputs", "targets": "train/targets"}
# Finally, build input_fns from your DataSources.
train_input_fn = train_source.get_input_fn(
"train_in", field_map, None,
FLAGS.batch_size) # None lets our input_fn run for an unbounded
# number of epochs.
test_input_fn = test_source.get_input_fn(
"test_in", field_map, 1,
FLAGS.batch_size) # For testing, we only want to run the input_fn
# for one epoch instead.
print("Processing model..")
# Fourth, we pipe our input_fns through our model for training and evaluation.
model.train(train_input_fn, steps=FLAGS.train_batches)
model.evaluate(test_input_fn)
if FLAGS.interactive:
print("Interactive decoding...")
# Fifth, you may optionally set up an interactive session to test your system by directly
# engaging with it.
vocab = Vocabulary(fname=params["vocab_file"])
decoding.cmd_decode(model, vocab)
class RNNEstimator(AbstractRecurrentEstimator):
def _model_fn(self, features, mode, params):
with tf.variable_scope(self.scope, reuse=tf.AUTO_REUSE):
self.extract_args(features, mode, params)
self.init_inputs()
self.build_cell()
self.build_obj()
if mode == tf.estimator.ModeKeys.PREDICT:
self.build_rt_decoder()
self.predictions = {
"inputs": self.features["inputs"],
"outputs": self.hypotheses,
"scores": self.scores
}
if "metadata" in self.features:
self.predictions["metadata"] = self.features["metadata"]
return tf.estimator.EstimatorSpec(mode,
predictions=self.predictions)
self.init_targets()
self.build_loss()
if mode == tf.estimator.ModeKeys.TRAIN:
self.build_optimizer()
for var in tf.trainable_variables():
# Add histograms for trainable variables
tf.summary.histogram(var.op.name, var)
return tf.estimator.EstimatorSpec(mode,
loss=self.reported_loss,
train_op=self.train_op)
if mode == tf.estimator.ModeKeys.EVAL:
print("Number of parameters: " +
str(self.get_num_model_params()))
self.eval_metric_ops = dict()
return tf.estimator.EstimatorSpec(
mode,
loss=self.reported_loss,
eval_metric_ops=self.eval_metric_ops)
@classmethod
def construct_expected_params(cls):
expected_params = super().construct_expected_params()
expected_params["src_vocab_file"] = cls.make_param("")
expected_params["tgt_vocab_file"] = cls.make_param("")
expected_params["src_vocab_size"] = cls.make_param(0)
expected_params["tgt_vocab_size"] = cls.make_param(0)
return expected_params
def extract_args(self, features, mode, params):
super().extract_args(features, mode, params)
if (self.hparams.src_vocab_size == 0
and self.hparams.tgt_vocab_size == 0
and self.hparams.src_vocab_file == ""
and self.hparams.tgt_vocab_file == ""):
self.src_vocab = self.vocab
self.tgt_vocab = self.vocab
else:
if self.hparams.src_vocab_size > 0:
self.src_vocab = Vocabulary(size=self.hparams.src_vocab_size)
else:
self.src_vocab = Vocabulary(fname=self.hparams.src_vocab_file)
if self.hparams.tgt_vocab_size > 0:
self.tgt_vocab = Vocabulary(size=self.hparams.tgt_vocab_size)
else:
self.tgt_vocab = Vocabulary(fname=self.hparams.tgt_vocab_file)
def init_inputs(self):
with tf.name_scope('init_encoder'):
inputs = tf.cast(self.features["inputs"], tf.int32)
self.batch_size = tf.shape(inputs)[0]
inputs_length = tf.cast(
tf.count_nonzero(inputs - self.vocab.end_token_id, -1),
tf.int32)
inputs_max_length = tf.reduce_max(inputs_length)
end_token = tf.ones(shape=[
self.batch_size, self.hparams.max_length - inputs_max_length
],
dtype=tf.int32) * self.vocab.end_token_id
# [batch_size, max_time_steps + 1]
self.inputs_sparse = tf.concat([inputs, end_token], axis=1)
def init_targets(self):
with tf.name_scope('init_decoder'):
targets = tf.cast(self.features["targets"], tf.int32)
targets_length = tf.cast(
tf.count_nonzero(targets - self.vocab.end_token_id, -1),
tf.int32)
targets_max_length = tf.reduce_max(targets_length)
end_token = tf.ones(shape=[
self.batch_size, self.hparams.max_length - targets_max_length
],
dtype=tf.int32) * self.vocab.end_token_id
# [batch_size, max_time_steps + 1]
self.targets_sparse = tf.concat([targets, end_token], axis=1)
self.targets_length = targets_length + 1
self.target_mask = tf.sequence_mask(lengths=self.targets_length,
maxlen=self.hparams.max_length,
dtype=tf.float32)
def build_cell(self):
sequence_length = tf.ones([self.batch_size],
dtype=tf.int32) * self.hparams.max_length
super().build_cell(sequence_length, self.src_vocab.size())
def build_obj(self):
output_layer = Dense(self.tgt_vocab.size(), name='output_projection')
self.logits = output_layer(self.outputs)
def build_rt_decoder(self):
with tf.name_scope('predict_decoder'):
self.hypotheses = tf.argmax(self.logits, -1)
self.scores = tf.reduce_sum(
tf.reduce_max(tf.nn.log_softmax(self.logits), -1), -1)
def main(_):
'''
This is a more complex example in which we build an Icecaps script involving
component chaining and multi-task learning. We recommend you start with
train_simple_example.py. In this example, we build a personalized conversation system
that combines paired and unpaired data, and applies MMI during decoding.
'''
print("Loading parameters..")
# When multiple estimators are involved, you can specify which hyperparameters in your
# params file belong to which estimator using scoping. See dummy_params/persona_mmi_example.params
# for an example. If no scope is specified, the hyperparameter is provided to all
# models in your architecture.
params = util.load_params(FLAGS.params_file)
print("Building model..")
model_dir = FLAGS.model_dir
if FLAGS.clean_model_dir:
util.clean_model_dir(model_dir)
# For this system, we will need to build three different estimators.
# The first estimator is a personalized seq2seq estimator that will be responsible for
# learning the conversational model.
first_model = PersonaSeq2SeqEstimator(model_dir, params, scope="first")
# The second estimator is a personalized seq2seq estimator that shares its decoder with
# the first model. This model will learn an autoencoder on an unpaired personalized
# data set. The purpose of this configuration is to influence the first model with
# stylistic information from the unpaired dataset.
# To construct this second estimator, we first build a seq2seq encoder separate from
# the first model. Then, we use an EstimatorChain to chain that encoder to the first
# model's decoder, allowing the two models to share that decoder.
second_model_encoder = Seq2SeqEncoderEstimator(model_dir,
params,
scope="second_encoder")
second_model = EstimatorChain([second_model_encoder, first_model.decoder],
model_dir,
params,
scope="second")
# The third estimator is used for MMI decoding. This model will learn the inverse
# function of the first model. During decoding, this estimator will be used to rerank
# hypotheses generated by the first model during beam search decoding. While this
# won't have much of an effect on our toy data sets, the purpose of this model in
# real-world settings is to penalize generic responses applicable to many contexts
# such as "I don't know."
mmi_model = PersonaSeq2SeqEstimator(model_dir,
params,
scope="mmi",
is_mmi_model=True)
model_group = EstimatorGroup([first_model, second_model, mmi_model],
model_dir,
params,
scope="group")
print("Getting sources..")
# We will use two DataSources for training and one for testing.
fields = {
"train/inputs": "int",
"train/targets": "int",
"train/speakers": "int"
}
paired_source = DataSource(FLAGS.paired_file, fields)
unpaired_source = DataSource(FLAGS.unpaired_file, fields)
test_source = DataSource(FLAGS.test_file, fields)
# We construct three field maps.
# The paired field map is similar to the field map shown in train_simple_example.py
# The unpaired field map maps train/inputs to both the estimator's inputs and targets,
# in order to train an autoencoder.
# The mmi field maps maps train/inputs to targets and train/targets to inputs, in
# order to learn the inverse of the first estimator.
paired_field_map = {
"inputs": "train/inputs",
"targets": "train/targets",
"speaker_ids": "train/speakers"
}
unpaired_field_map = {
"inputs": "train/inputs",
"targets": "train/inputs",
"speaker_ids": "train/speakers"
}
mmi_field_map = {
"inputs": "train/targets",
"targets": "train/inputs",
"speaker_ids": "train/speakers"
}
paired_input_fn = paired_source.get_input_fn("paired_in", paired_field_map,
None, FLAGS.batch_size)
unpaired_input_fn = unpaired_source.get_input_fn("unpaired_in",
unpaired_field_map, None,
FLAGS.batch_size)
mmi_input_fn = paired_source.get_input_fn("mmi_in", mmi_field_map, None,
FLAGS.batch_size)
# For multi-task learning, you will need to group your input_fns together with group_input_fns().
train_input_fn = DataSource.group_input_fns(
["first", "second", "mmi"],
[paired_input_fn, unpaired_input_fn, mmi_input_fn])
test_input_fn = test_source.get_input_fn("test_in", paired_field_map, 1,
FLAGS.batch_size)
print("Processing models..")
# Icecaps supports flexible multi-task training pipelines. You can set up multiple phases
# where each phase trains your architecture with different weights across your objectives.
# In this example, we will first pre-train the first model by itself, then jointly train
# the first and second models, then finally train the MMI model by itself.
print("Pretraining primary model..")
model_group.train(train_input_fn,
first_model,
steps=FLAGS.pretrain_batches)
print("Multitask training..")
model_group.train(train_input_fn, {
"first": 1,
"second": 1,
"mmi": 0
},
steps=FLAGS.train_batches)
print("Training MMI model..")
model_group.train(train_input_fn, mmi_model, steps=FLAGS.mmi_batches)
print("Evaluating..")
model_group.evaluate(test_input_fn, first_model)
if FLAGS.interactive:
print("Interactive decoding...")
vocab = Vocabulary(fname=params["vocab_file"])
# To decode with MMI, you can pass in your MMI model to cmd_decode().
# lambda_balance represents how the first model and MMI model's scores are weighted during decoding.
decoding.cmd_decode(first_model,
vocab,
persona=True,
mmi_component=mmi_model,
lambda_balance=FLAGS.lambda_balance)
