def __init__(self, embedding=None, vocab_size=None, hparams=None):
ModuleBase.__init__(self, hparams)
self._vocab_size = vocab_size
self._embedding = None
self.sampling_method = self._hparams.sampling_method
with tf.variable_scope(self.variable_scope):
if self._hparams.initializer:
tf.get_variable_scope().set_initializer( \
layers.get_initializer(self._hparams.initializer))
if self._hparams.position_embedder.name == 'sinusoids':
self.position_embedder = \
position_embedders.SinusoidsSegmentalPositionEmbedder( \
self._hparams.position_embedder.hparams)
if self._hparams.use_embedding:
if embedding is None and vocab_size is None:
raise ValueError("""If 'embedding' is not provided,
'vocab_size' must be specified.""")
if isinstance(embedding, (tf.Tensor, tf.Variable)):
self._embedding = embedding
else:
self._embedding = embedder_utils.get_embedding(
self._hparams.embedding,
embedding,
vocab_size,
variable_scope=self.variable_scope)
self._embed_dim = shape_list(self._embedding)[-1]
if self._hparams.zero_pad:
self._embedding = tf.concat( \
(tf.zeros(shape=[1, self._embed_dim]),\
self._embedding[1:, :]), 0)
if self._vocab_size is None:
self._vocab_size = self._embedding.get_shape().as_list()[0]
self.output_layer = \
self.build_output_layer(shape_list(self._embedding)[-1])
def __init__(self, hparams=None):
EncoderBase.__init__(self, hparams)
with tf.variable_scope(self.variable_scope):
if self._hparams.initializer:
tf.get_variable_scope().set_initializer(
layers.get_initializer(self._hparams.initializer))
self.multihead_attention_list = []
self.poswise_networks = []
for i in range(self._hparams.num_blocks):
with tf.variable_scope("layer_{}".format(i)):
with tf.variable_scope('attention'):
mh_attn = MultiheadAttentionEncoder(
self._hparams.multihead_attention)
self.multihead_attention_list.append(mh_attn)
if self._hparams.dim != mh_attn.hparams.output_dim:
raise ValueError(
'The "dim" in the hparams of '
'"multihead_attention" should be equal to the '
'"dim" of TransformerEncoder')
pw_net = FeedForwardNetwork(
hparams=self._hparams['poswise_feedforward'])
final_dim = pw_net.hparams.layers[-1]['kwargs']['units']
if self._hparams.dim != final_dim:
raise ValueError(
'The output dimenstion of '
'"poswise_feedforward" should be equal '
'to the "dim" of TransformerEncoder.')
self.poswise_networks.append(pw_net)
def __init__(self, input_size: int, hparams=None):
super().__init__(hparams=hparams)
use_bias = self._hparams.use_bias
self.Q_dense = nn.Linear(input_size,
self._hparams.num_units,
bias=use_bias)
self.K_dense = nn.Linear(input_size,
self._hparams.num_units,
bias=use_bias)
self.V_dense = nn.Linear(input_size,
self._hparams.num_units,
bias=use_bias)
self.O_dense = nn.Linear(self._hparams.num_units,
self._hparams.output_dim,
bias=use_bias)
if self._hparams.initializer:
# TODO(haoransh): we may define kernel_initializer and bias
# initializer seperately
initialize = layers.get_initializer(self._hparams.initializer)
assert initialize is not None
for name, param in self.named_parameters():
if name.split('.')[-1] == 'weight':
print('name:{}'.format(name))
initialize(param)
def reset_parameters(self):
initialize = layers.get_initializer(self._hparams.initializer)
if initialize is not None:
# Do not re-initialize LayerNorm modules.
for name, param in self.named_parameters():
if name.split('.')[-1] == 'weight' and 'layer_norm' not in name:
initialize(param)
def __init__(self, vocab_size=None, output_layer=None, hparams=None):
ModuleBase.__init__(self, hparams)
with tf.variable_scope(self.variable_scope):
if self._hparams.initializer:
tf.get_variable_scope().set_initializer(
layers.get_initializer(self._hparams.initializer))
# Make the output layer
self._output_layer, self._vocab_size = _make_output_layer(
output_layer, vocab_size, self._hparams.output_layer_bias,
self.variable_scope)
# Make attention and poswise networks
self.multihead_attentions = {'self_att': [], 'encdec_att': []}
self.poswise_networks = []
for i in range(self._hparams.num_blocks):
layer_name = 'layer_{}'.format(i)
with tf.variable_scope(layer_name):
with tf.variable_scope("self_attention"):
multihead_attention = MultiheadAttentionEncoder(
self._hparams.multihead_attention)
self.multihead_attentions['self_att'].append(
multihead_attention)
if self._hparams.dim != \
multihead_attention.hparams.output_dim:
raise ValueError('The output dimenstion of '
'MultiheadEncoder should be equal '
'to the dim of TransformerDecoder')
with tf.variable_scope('encdec_attention'):
multihead_attention = MultiheadAttentionEncoder(
self._hparams.multihead_attention)
self.multihead_attentions['encdec_att'].append(
multihead_attention)
if self._hparams.dim != \
multihead_attention.hparams.output_dim:
raise ValueError('The output dimenstion of '
'MultiheadEncoder should be equal '
'to the dim of TransformerDecoder')
pw_net = FeedForwardNetwork(
hparams=self._hparams['poswise_feedforward'])
final_dim = pw_net.hparams.layers[-1]['kwargs']['units']
if self._hparams.dim != final_dim:
raise ValueError(
'The output dimenstion of '
'"poswise_feedforward" should be equal '
'to the "dim" of TransformerDecoder.')
self.poswise_networks.append(pw_net)
# Built in _build()
self.context = None
self.context_sequence_length = None
self.embedding = None
self._helper = None
self._cache = None
self.max_decoding_length = None
def __init__(self, embedding, hparams=None):
ModuleBase.__init__(self, hparams)
with tf.variable_scope(self.variable_scope):
if self._hparams.initializer:
tf.get_variable_scope().set_initializer(
layers.get_initializer(self._hparams.initializer))
if self._hparams.position_embedder_type == 'sinusoids':
self.position_embedder = SinusoidsPositionEmbedder(
self._hparams.position_embedder_hparams)
else:
self.position_embedder = PositionEmbedder(
position_size=self._hparams.position_size,
hparams=self._hparams.position_embedder_hparams)
self._embedding = embedding
self._vocab_size = self._embedding.get_shape().as_list()[0]
self.output_layer = \
self._build_output_layer(shape_list(self._embedding)[-1])
self.multihead_attentions = {'self_att': [], 'encdec_att': []}
self.poswise_networks = []
for i in range(self._hparams.num_blocks):
layer_name = 'layer_{}'.format(i)
with tf.variable_scope(layer_name):
with tf.variable_scope("self_attention"):
multihead_attention = MultiheadAttentionEncoder(
self._hparams.multihead_attention)
self.multihead_attentions['self_att'].append(
multihead_attention)
# pylint: disable=protected-access
if self._hparams.dim != \
multihead_attention._hparams.output_dim:
raise ValueError('The output dimenstion of '
'MultiheadEncoder should be equal '
'to the dim of TransformerDecoder')
with tf.variable_scope('encdec_attention'):
multihead_attention = MultiheadAttentionEncoder(
self._hparams.multihead_attention)
self.multihead_attentions['encdec_att'].append(
multihead_attention)
if self._hparams.dim != \
multihead_attention._hparams.output_dim:
raise ValueError('The output dimenstion of '
'MultiheadEncoder should be equal '
'to the dim of TransformerDecoder')
poswise_network = FeedForwardNetwork(
hparams=self._hparams['poswise_feedforward'])
if self._hparams.dim != \
poswise_network._hparams.layers[-1]['kwargs']['units']:
raise ValueError('The output dimenstion of '
'FeedForwardNetwork should be equal '
'to the dim of TransformerDecoder')
self.poswise_networks.append(poswise_network)
def __init__(self,
pretrained_model_name: Optional[str] = None,
cache_dir: Optional[str] = None,
hparams=None):
super().__init__(hparams=hparams)
# Create the underlying encoder
encoder_hparams = dict_fetch(hparams, XLNetEncoder.default_hparams())
self._encoder = XLNetEncoder(
pretrained_model_name=pretrained_model_name,
cache_dir=cache_dir,
hparams=encoder_hparams)
# TODO: The logic here is very similar to that in XLNetClassifier.
# We need to reduce the code redundancy.
if self._hparams.use_projection:
if self._hparams.regr_strategy == 'all_time':
self.projection = nn.Linear(
self._encoder.output_size * self._hparams.max_seq_length,
self._encoder.output_size * self._hparams.max_seq_length)
else:
self.projection = nn.Linear(self._encoder.output_size,
self._encoder.output_size)
self.dropout = nn.Dropout(self._hparams.dropout)
logit_kwargs = self._hparams.logit_layer_kwargs
if logit_kwargs is None:
logit_kwargs = {}
elif not isinstance(logit_kwargs, HParams):
raise ValueError("hparams['logit_layer_kwargs'] "
"must be a dict.")
else:
logit_kwargs = logit_kwargs.todict()
if self._hparams.regr_strategy == 'all_time':
self.hidden_to_logits = nn.Linear(
self._encoder.output_size * self._hparams.max_seq_length, 1,
**logit_kwargs)
else:
self.hidden_to_logits = nn.Linear(self._encoder.output_size, 1,
**logit_kwargs)
if self._hparams.initializer:
initialize = get_initializer(self._hparams.initializer)
assert initialize is not None
if self._hparams.use_projection:
initialize(self.projection.weight)
initialize(self.projection.bias)
initialize(self.hidden_to_logits.weight)
if self.hidden_to_logits.bias:
initialize(self.hidden_to_logits.bias)
else:
if self._hparams.use_projection:
self.projection.apply(init_weights)
self.hidden_to_logits.apply(init_weights)
def __init__(self, hparams=None):
EncoderBase.__init__(self, hparams)
with tf.variable_scope(self.variable_scope):
if self._hparams.initializer:
tf.get_variable_scope().set_initializer(
layers.get_initializer(self._hparams.initializer))
self.position_embedder = \
SinusoidsPositionEmbedder(
self._hparams.position_embedder_hparams)
def __init__(self,
pretrained_model_name: Optional[str] = None,
cache_dir: Optional[str] = None,
hparams=None):
super().__init__(hparams=hparams)
# Create the underlying encoder
encoder_hparams = dict_fetch(hparams, GPT2Encoder.default_hparams())
self._encoder = GPT2Encoder(
pretrained_model_name=pretrained_model_name,
cache_dir=cache_dir,
hparams=encoder_hparams)
# Create a dropout layer
self._dropout_layer = nn.Dropout(self._hparams.dropout)
# Create an additional classification layer if needed
self.num_classes = self._hparams.num_classes
if self.num_classes <= 0:
self._logits_layer = None
else:
logit_kwargs = self._hparams.logit_layer_kwargs
if logit_kwargs is None:
logit_kwargs = {}
elif not isinstance(logit_kwargs, HParams):
raise ValueError("hparams['logit_layer_kwargs'] "
"must be a dict.")
else:
logit_kwargs = logit_kwargs.todict()
if self._hparams.clas_strategy == 'all_time':
self._logits_layer = nn.Linear(
self._encoder.output_size * self._hparams.max_seq_length,
self.num_classes, **logit_kwargs)
else:
self._logits_layer = nn.Linear(self._encoder.output_size,
self.num_classes,
**logit_kwargs)
if self._hparams.initializer:
initialize = get_initializer(self._hparams.initializer)
assert initialize is not None
if self._logits_layer is not None:
initialize(self._logits_layer.weight)
if self._logits_layer.bias is not None:
initialize(self._logits_layer.bias)
self.is_binary = (self.num_classes == 1) or \
(self.num_classes <= 0 and
self._hparams.dim == 1)
def get_embedding(hparams=None,
init_value=None,
num_embeds=None,
variable_scope='Embedding'):
"""Creates embedding variable if not exists.
Args:
hparams (dict or HParams, optional): Embedding hyperparameters. Missing
hyperparameters are set to default values. See
:func:`~texar.modules.default_embedding_hparams`
for all hyperparameters and default values.
If :attr:`init_value` is given, :attr:`hparams["initializer"]`,
and :attr:`hparams["dim"]` are ignored.
init_value (Tensor or numpy array, optional): Initial values of the
embedding variable. If not given, embedding is initialized as
specified in :attr:`hparams["initializer"]`.
num_embeds (int, optional): The number of embedding items
(e.g., vocabulary size). Required if :attr:`init_value` is
not provided.
variable_scope (str or VariableScope, optional): Variable scope of
the embedding variable.
Returns:
Variable or Tensor: A 2D `Variable` or `Tensor` of the same shape with
:attr:`init_value` or of the shape
:attr:`[num_embeds, hparams["dim"]]`.
"""
with tf.variable_scope(variable_scope):
if hparams is None or isinstance(hparams, dict):
hparams = HParams(hparams, default_embedding_hparams())
regularizer = layers.get_regularizer(hparams["regularizer"])
if init_value is None:
initializer = layers.get_initializer(hparams["initializer"])
dim = hparams["dim"]
if not isinstance(hparams["dim"], (list, tuple)):
dim = [dim]
embedding = tf.get_variable(name='w',
shape=[num_embeds] + dim,
initializer=initializer,
regularizer=regularizer,
trainable=hparams["trainable"])
else:
init_value = tf.cast(init_value, tf.float32)
embedding = tf.get_variable(name='w',
initializer=init_value,
regularizer=regularizer,
trainable=hparams["trainable"])
return embedding
def __init__(self,
vocab_size=None,
output_layer=None,
tau=None,
hparams=None):
EncoderBase.__init__(self, hparams)
with tf.variable_scope(self.variable_scope):
if self._hparams.initializer:
tf.get_variable_scope().set_initializer(
layers.get_initializer(self._hparams.initializer))
# Make the output layer
self._output_layer, self._vocab_size = _make_output_layer(
output_layer, vocab_size, self._hparams.output_layer_bias,
self.variable_scope)
# Make attention and poswise networks
self.graph_multihead_attention_list = []
self.poswise_networks = []
for i in range(self._hparams.num_blocks):
with tf.variable_scope("layer_{}".format(i)):
with tf.variable_scope('attention'):
mh_attn = GraphMultiheadAttentionEncoder(
self._hparams.graph_multihead_attention)
self.graph_multihead_attention_list.append(mh_attn)
if self._hparams.dim != mh_attn.hparams.output_dim:
raise ValueError(
'The "dim" in the hparams of '
'"multihead_attention" should be equal to the '
'"dim" of CrossGraphTransformerFixedLengthDecoder'
)
pw_net = FeedForwardNetwork(
hparams=self._hparams['poswise_feedforward'])
final_dim = pw_net.hparams.layers[-1]['kwargs']['units']
if self._hparams.dim != final_dim:
raise ValueError(
'The output dimenstion of '
'"poswise_feedforward" should be equal '
'to the "dim" of CrossGraphTransformerFixedLengthDecoder.'
)
self.poswise_networks.append(pw_net)
self._helper = None
self._tau = tau
def __init__(self, hparams=None):
EncoderBase.__init__(self, hparams)
with tf.variable_scope(self.variable_scope):
if self._hparams.initializer:
tf.get_variable_scope().set_initializer(
layers.get_initializer(self._hparams.initializer))
if self._hparams.position_embedder_type == 'sinusoids':
self.position_embedder = SinusoidsPositionEmbedder(
self._hparams.position_embedder_hparams)
else:
self.position_embedder = PositionEmbedder(
position_size=self._hparams.position_size,
hparams=self._hparams.position_embedder_hparams)
# pylint: disable=protected-access
if self._hparams.dim != \
self.position_embedder._hparams.dim:
raise ValueError('"dim" in '
'TransformerEncoder hparams must be equal '
'to "dim" in its '
'position_embedder_hparams.')
self.multihead_attention_list = []
self.poswise_networks = []
for i in range(self._hparams.num_blocks):
with tf.variable_scope("layer_{}".format(i)):
with tf.variable_scope('attention'):
multihead_attention = MultiheadAttentionEncoder(
self._hparams.multihead_attention)
self.multihead_attention_list.append(
multihead_attention)
# pylint: disable=protected-access
if self._hparams.dim != \
multihead_attention._hparams.output_dim:
raise ValueError('The "dim" in the hparams of '
'multihead_attention should be equal '
'to the "dim" of TransformerEncoder')
poswise_network = FeedForwardNetwork(
hparams=self._hparams['poswise_feedforward'])
# pylint: disable=protected-access
if self._hparams.dim != \
poswise_network._hparams.layers[-1]['kwargs']['units']:
# poswise_network._hparams.layers[-1]['units']:
raise ValueError('The "units" in the "kwargs" of '
'FeedForwardNetwork should be equal '
'to the "dim" of TransformerEncoder')
self.poswise_networks.append(poswise_network)
def __init__(self, embedding, hparams=None):
ModuleBase.__init__(self, hparams)
with tf.variable_scope(self.variable_scope):
if self._hparams.initializer:
tf.get_variable_scope().set_initializer( \
layers.get_initializer(self._hparams.initializer))
self.position_embedder = \
SinusoidsPositionEmbedder(
self._hparams.position_embedder_hparams)
self._embedding = embedding
self._vocab_size = self._embedding.get_shape().as_list()[0]
self.output_layer = \
self._build_output_layer(shape_list(self._embedding)[-1])
def get_embedding(num_embeds: Optional[int] = None,
init_value: Optional[torch.Tensor] = None,
hparams=None):
r"""Creates embedding variable if not exists.
Args:
hparams (dict or HParams, optional): Embedding hyperparameters. Missing
hyperparameters are set to default values. See
:func:`~texar.modules.default_embedding_hparams`
for all hyperparameters and default values.
If :attr:`init_value` is given, :attr:`hparams["initializer"]`,
and :attr:`hparams["dim"]` are ignored.
init_value (Tensor or numpy array, optional): Initial values of the
embedding variable. If not given, embedding is initialized as
specified in :attr:`hparams["initializer"]`.
num_embeds (int, optional): The number of embedding items
(e.g., vocabulary size). Required if :attr:`init_value` is
not provided.
Returns:
A 2D :tensor:`Tensor` of the same shape with :attr:`init_value` or of
the shape ``[num_embeds, hparams["dim"]]``.
"""
if hparams is None or isinstance(hparams, dict):
hparams = HParams(hparams, default_embedding_hparams())
if init_value is None:
initializer = layers.get_initializer(
getattr(hparams, "initializer", None))
# TODO Shibiao: add regularizer
dim = hparams["dim"]
if not isinstance(hparams["dim"], (list, tuple)):
dim = [dim]
embedding = torch.empty(size=[num_embeds] + dim)
# initializer should be set by layers.get_initializer
if initializer:
embedding = initializer(embedding)
else:
embedding = torch.nn.init.xavier_uniform_(embedding)
else:
if torch.is_tensor(init_value):
embedding = init_value # Do not copy the tensor.
else:
embedding = torch.tensor(init_value, dtype=torch.float)
return embedding
def __init__(self,
pretrained_model_name: Optional[str] = None,
cache_dir: Optional[str] = None,
hparams=None):
super().__init__(pretrained_model_name=pretrained_model_name,
cache_dir=cache_dir,
hparams=hparams)
if self.pretrained_model_dir:
self._hparams = HParams(self.pretrained_model_hparams,
self._hparams.todict())
# Word embedding
self.word_embedder = WordEmbedder(vocab_size=self._hparams.vocab_size,
hparams=self._hparams.embed)
# Segment embedding for each type of tokens
self.segment_embedder = WordEmbedder(
vocab_size=self._hparams.type_vocab_size,
hparams=self._hparams.segment_embed)
# Position embedding
self.position_embedder = PositionEmbedder(
position_size=self._hparams.position_size,
hparams=self._hparams.position_embed)
# The BERT encoder (a TransformerEncoder)
self.encoder = TransformerEncoder(hparams=self._hparams.encoder)
self.pooler = nn.Sequential(
nn.Linear(self._hparams.hidden_size, self._hparams.hidden_size),
nn.Tanh())
if self.pretrained_model_dir:
bert_utils.init_bert_checkpoint(self, self.pretrained_model_dir)
elif self._hparams.initializer:
initialize = layers.get_initializer(self._hparams.initializer)
assert initialize is not None
# Do not re-initialize LayerNorm modules.
for name, param in self.named_parameters():
if name.split(
'.')[-1] == 'weight' and 'layer_norm' not in name:
initialize(param)
def __init__(self, hparams=None):
EncoderBase.__init__(self, hparams)
with tf.variable_scope(self.variable_scope):
if self._hparams.initializer:
tf.get_variable_scope().set_initializer(
layers.get_initializer(self._hparams.initializer))
self.Q_dense = tf.layers.Dense(self._hparams.num_units,
use_bias=False,
name='q')
self.K_dense = tf.layers.Dense(self._hparams.num_units,
use_bias=False,
name='k')
self.V_dense = tf.layers.Dense(self._hparams.num_units,
use_bias=False,
name='v')
self.O_dense = tf.layers.Dense(self._hparams.output_dim,
use_bias=False,
name='o')
def __init__(self,
pretrained_model_name=None,
cache_dir=None,
hparams=None):
EncoderBase.__init__(self, hparams)
BertBase.__init__(self, pretrained_model_name, cache_dir,
hparams) # put these things to BertBase
if self.pretrained_model:
self._hparams = HParams(self.pretrained_model_hparams,
self._hparams.todict())
with tf.variable_scope(self.variable_scope):
if self._hparams.initializer:
tf.get_variable_scope().set_initializer(
layers.get_initializer(self._hparams.initializer))
# Word embedding
self.word_embedder = WordEmbedder(
vocab_size=self._hparams.vocab_size,
hparams=self._hparams.embed)
# Segment embedding for each type of tokens
self.segment_embedder = WordEmbedder(
vocab_size=self._hparams.type_vocab_size,
hparams=self._hparams.segment_embed)
# Position embedding
self.position_embedder = PositionEmbedder(
position_size=self._hparams.position_size,
hparams=self._hparams.position_embed)
# The BERT encoder (a TransformerEncoder)
self.encoder = TransformerEncoder(hparams=self._hparams.encoder)
with tf.variable_scope("pooler"):
kwargs_i = {
"units": self._hparams.hidden_size,
"activation": tf.tanh
}
layer_hparams = {"type": "Dense", "kwargs": kwargs_i}
self.pooler = layers.get_layer(hparams=layer_hparams)
def __init__(self, hparams=None):
EncoderBase.__init__(self, hparams)
use_bias = self._hparams.use_bias
with tf.variable_scope(self.variable_scope):
if self._hparams.initializer:
tf.get_variable_scope().set_initializer(
layers.get_initializer(self._hparams.initializer))
self.Q_dense = tf.layers.Dense(self._hparams.num_units,
use_bias=use_bias,
name='query')
self.K_dense = tf.layers.Dense(self._hparams.num_units,
use_bias=use_bias,
name='key')
self.V_dense = tf.layers.Dense(self._hparams.num_units,
use_bias=use_bias,
name='value')
self.O_dense = tf.layers.Dense(self._hparams.output_dim,
use_bias=use_bias,
name='output')
def __init__(self, embedding, vocab_size=None, hparams=None):
EncoderBase.__init__(self, hparams)
self._vocab_size = vocab_size
self._embedding = None
self.enc = None
with tf.variable_scope(self.variable_scope):
if self._hparams.initializer:
tf.get_variable_scope().set_initializer(
layers.get_initializer(self._hparams.initializer))
if self._hparams.position_embedder.name == 'sinusoids':
self.position_embedder = \
position_embedders.SinusoidsPositionEmbedder(\
self._hparams.position_embedder.hparams)
if self._hparams.use_embedding:
if isinstance(embedding, tf.Variable):
self._embedding = embedding
embed_dim = self._embedding.get_shape().as_list()[-1]
if self._hparams.zero_pad: # TODO(zhiting): vocab has zero pad
if not self._hparams.bos_pad:
self._embedding = tf.concat(\
(tf.zeros(shape=[1, embed_dim]),
self._embedding[1:, :]), 0)
else:
self._embedding = tf.concat(\
(tf.zeros(shape=[2, embed_dim]),
self._embedding[2:, :]), 0)
if self._vocab_size is None:
self._vocab_size = self._embedding.get_shape().as_list()[0]
with tf.variable_scope(self.variable_scope):
if self._hparams.target_space_id is not None:
space_embedding = tf.get_variable('target_space_embedding', \
[32, embed_dim])
self.target_symbol_embedding = tf.gather(space_embedding, \
self._hparams.target_space_id)
else:
self.target_symbol_embedding = None
self.stack_output = None
def __init__(self,
pretrained_model_name: Optional[str] = None,
cache_dir: Optional[str] = None,
hparams=None):
super().__init__(pretrained_model_name=pretrained_model_name,
cache_dir=cache_dir,
hparams=hparams)
if self.pretrained_model_dir:
self._hparams = HParams(self.pretrained_model_hparams,
self._hparams.todict())
# Word embedding
self.word_embedder = WordEmbedder(vocab_size=self._hparams.vocab_size,
hparams=self._hparams.embed)
# Position embedding
self.position_embedder = PositionEmbedder(
position_size=self._hparams.position_size,
hparams=self._hparams.position_embed)
# The GPT2 decoder (a TransformerDecoder)
self.decoder = TransformerDecoder(
vocab_size=self._hparams.vocab_size,
output_layer=self.word_embedder.embedding,
hparams=self._hparams.decoder)
if self.pretrained_model_dir:
gpt2_utils.init_gpt2_checkpoint(self, self.pretrained_model_dir)
elif self._hparams.initializer:
initialize = layers.get_initializer(self._hparams.initializer)
assert initialize is not None
# Do not re-initialize LayerNorm modules.
for name, param in self.named_parameters():
if name.split(
'.')[-1] == 'weight' and 'layer_norm' not in name:
initialize(param)
def __init__(self, hparams=None):
EncoderBase.__init__(self, hparams)
with tf.variable_scope(self.variable_scope):
if self._hparams.initializer:
tf.get_variable_scope().set_initializer(
layers.get_initializer(self._hparams.initializer))
self.position_embedder = \
SinusoidsPositionEmbedder(
self._hparams.position_embedder_hparams)
self.multihead_attention_list = []
self.poswise_networks = []
for i in range(self._hparams.num_blocks):
with tf.variable_scope("layer_{}".format(i)):
with tf.variable_scope('self_attention'):
multihead_attention = MultiheadAttentionEncoder(
self._hparams.multihead_attention)
self.multihead_attention_list.append(
multihead_attention)
# pylint: disable=protected-access
if self._hparams.dim != \
multihead_attention._hparams.output_dim:
raise ValueError('The output dimenstion of'
'MultiheadEncoder should be equal'
'to the dim of TransformerEncoder')
poswise_network = FeedForwardNetwork(
hparams=self._hparams['poswise_feedforward'])
# pylint: disable=protected-access
if self._hparams.dim != \
poswise_network._hparams.layers[-1]['kwargs']['units']:
# poswise_network._hparams.layers[-1]['units']:
raise ValueError('The output dimenstion of'
'FeedForwardNetwork should be equal'
'to the dim of TransformerEncoder')
self.poswise_networks.append(poswise_network)
def __init__(self, hparams=None):
EncoderBase.__init__(self, hparams)
self._input_size = self._hparams.dim
self.self_attns = nn.ModuleList()
if not self._hparams.use_bert_config:
self.self_attn_layer_norm = nn.ModuleList()
self.poswise_networks = nn.ModuleList()
self.poswise_layer_norm = nn.ModuleList()
self.output_layer_norm = nn.ModuleList()
if self._hparams.use_bert_config:
# In TensorFlow, eps for LayerNorm is 1e-12 by default.
eps = 1e-12
else:
# In PyTorch, eps for LayerNorm is 1e-6 by default.
eps = 1e-6
for _ in range(self._hparams.num_blocks):
mh_attn = MultiheadAttentionEncoder(
self._input_size, self._hparams.multihead_attention)
self.self_attns.append(mh_attn)
if not self._hparams.use_bert_config:
self.self_attn_layer_norm.append(
nn.LayerNorm(self._input_size, eps=eps))
if self._hparams.dim != mh_attn.hparams.output_dim:
raise ValueError(
'The "dim" in the hparams of '
'"multihead_attention" should be equal to the '
'"dim" of TransformerEncoder')
pw_net = FeedForwardNetwork(
hparams=self._hparams['poswise_feedforward'])
final_dim = pw_net.hparams.layers[-1]['kwargs']['out_features']
if self._hparams.dim != final_dim:
raise ValueError('The output dimenstion of '
'"poswise_feedforward" should be equal '
'to the "dim" of TransformerEncoder.')
self.poswise_networks.append(pw_net)
self.poswise_layer_norm.append(
nn.LayerNorm(self._input_size, eps=eps))
if self._hparams.use_bert_config:
self.output_layer_norm.append(
nn.LayerNorm(self._input_size, eps=eps))
self.embed_dropout = nn.Dropout(p=self._hparams.embedding_dropout)
self.residual_dropout = nn.Dropout(p=self._hparams.residual_dropout)
if self._hparams.use_bert_config:
self.input_normalizer = nn.LayerNorm(self._input_size, eps=eps)
else:
self.final_layer_normalizer = nn.LayerNorm(self._input_size,
eps=eps)
if self._hparams.initializer:
initialize = layers.get_initializer(self._hparams.initializer)
assert initialize is not None
# Do not re-initialize LayerNorm modules.
for name, param in self.named_parameters():
if name.split(
'.')[-1] == 'weight' and 'layer_norm' not in name:
initialize(param)
def __init__(self,
vocab_size: Optional[int] = None,
output_layer: Optional[Union[nn.Module, torch.Tensor]] = None,
hparams: Optional[HParams] = None):
super().__init__(
0,
vocab_size, # dummy value for input_size
input_time_major=False,
output_time_major=False,
hparams=hparams)
self._input_size = self._hparams.dim
self._output_layer, self._vocab_size = _make_output_layer(
output_layer, vocab_size, self._input_size,
self._hparams.output_layer_bias)
self.self_attns = nn.ModuleList()
self.self_attn_layer_norm = nn.ModuleList()
self.enc_dec_attns = nn.ModuleList()
self.end_dec_attn_layer_norm = nn.ModuleList()
self.poswise_networks = nn.ModuleList()
self.poswise_layer_norm = nn.ModuleList()
if self._hparams.use_gpt_config:
eps = 1e-5
else:
eps = 1e-12
for _ in range(self._hparams.num_blocks):
attn_module = MultiheadAttentionEncoder(
self._input_size, self._hparams.multihead_attention)
if self._hparams.dim != attn_module.output_size:
raise ValueError("The output dimension of "
"MultiheadEncoder should be equal "
"to the dim of TransformerDecoder")
self.self_attns.append(attn_module)
self.self_attn_layer_norm.append(
nn.LayerNorm(self._input_size, eps=eps))
attn_module = MultiheadAttentionEncoder(
self._input_size, self._hparams.multihead_attention)
if self._hparams.dim != attn_module.output_size:
raise ValueError("The output dimension of "
"MultiheadEncoder should be equal "
"to the dim of TransformerDecoder")
self.enc_dec_attns.append(attn_module)
self.end_dec_attn_layer_norm.append(
nn.LayerNorm(self._input_size, eps=eps))
poswise_network = FeedForwardNetwork(
hparams=self._hparams.poswise_feedforward)
if (poswise_network.hparams.layers[-1]['kwargs']['out_features'] !=
self._hparams.dim):
raise ValueError("The output dimension of "
"FeedForwardNetwork should be equal "
"to the dim of TransformerDecoder")
self.poswise_networks.append(poswise_network)
self.poswise_layer_norm.append(
nn.LayerNorm(self._input_size, eps=eps))
self.final_layer_norm = nn.LayerNorm(self._input_size, eps=eps)
self.embed_dropout = nn.Dropout(self._hparams.embedding_dropout)
self.residual_dropout = nn.Dropout(self._hparams.residual_dropout)
if self._hparams.initializer:
# TODO: This might be different to what TensorFlow does
initialize = layers.get_initializer(self._hparams.initializer)
assert initialize is not None
# Do not re-initialize LayerNorm modules.
for name, param in self.named_parameters():
if name.split(
".")[-1] == "weight" and "layer_norm" not in name:
initialize(param)
