def _decode(self, input_dict):
        if 'target_tensors' in input_dict:
            targets = input_dict['target_tensors'][0]
        else:
            targets = None
        encoder_outputs = input_dict['encoder_output']['outputs']
        inputs_attention_bias = (
            input_dict['encoder_output']['inputs_attention_bias'])
        self.embedding_softmax_layer = (
            input_dict['encoder_output']['embedding_softmax_layer'])

        with tf.name_scope("decode"):
            # prepare decoder layers
            if len(self.layers) == 0:
                for _ in range(self.params["num_hidden_layers"]):
                    self_attention_layer = attention_layer.SelfAttention(
                        self.params["hidden_size"],
                        self.params["num_heads"],
                        self.params["attention_dropout"],
                        self.mode == "train",
                    )
                    enc_dec_attention_layer = attention_layer.Attention(
                        self.params["hidden_size"],
                        self.params["num_heads"],
                        self.params["attention_dropout"],
                        self.mode == "train",
                    )
                    feed_forward_network = ffn_layer.FeedFowardNetwork(
                        self.params["hidden_size"],
                        self.params["filter_size"],
                        self.params["relu_dropout"],
                        self.mode == "train",
                    )

                    self.layers.append([
                        PrePostProcessingWrapper(self_attention_layer,
                                                 self.params,
                                                 self.mode == "train"),
                        PrePostProcessingWrapper(enc_dec_attention_layer,
                                                 self.params,
                                                 self.mode == "train"),
                        PrePostProcessingWrapper(feed_forward_network,
                                                 self.params,
                                                 self.mode == "train")
                    ])

                self.output_normalization = LayerNormalization(
                    self.params["hidden_size"])

            if targets is None:
                return self.predict(encoder_outputs, inputs_attention_bias)
            else:
                logits = self.decode_pass(targets, encoder_outputs,
                                          inputs_attention_bias)
                return {
                    "logits": logits,
                    "outputs": [tf.argmax(logits, axis=-1)],
                    "final_state": None,
                    "final_sequence_lengths": None
                }
Beispiel #2
0
  def _encode(self, input_dict):
    if len(self.layers) == 0:
      # prepare encoder graph
      self.embedding_softmax_layer = embedding_layer.EmbeddingSharedWeights(
        self.params["src_vocab_size"], self.params["hidden_size"],
        pad_vocab_to_eight=self.params.get('pad_embeddings_2_eight', False))

      for _ in range(self.params['encoder_layers']):
        # Create sublayers for each layer.
        self_attention_layer = attention_layer.SelfAttention(
          self.params["hidden_size"], self.params["num_heads"],
          self.params["attention_dropout"], self.mode == "train")
        feed_forward_network = ffn_layer.FeedFowardNetwork(
          self.params["hidden_size"], self.params["filter_size"],
          self.params["relu_dropout"], self.mode == "train")

        self.layers.append([
          PrePostProcessingWrapper(self_attention_layer, self.params,
                                   self.mode == "train"),
          PrePostProcessingWrapper(feed_forward_network, self.params,
                                   self.mode == "train")])

      # Create final layer normalization layer.
      self.output_normalization = LayerNormalization(self.params["hidden_size"])

    # actual encoder part
    with tf.name_scope("encode"):
      #inputs = input_dict['src_sequence']
      inputs = input_dict['source_tensors'][0]
      # Prepare inputs to the layer stack by adding positional encodings and
      # applying dropout.
      embedded_inputs = self.embedding_softmax_layer(inputs)
      inputs_padding = utils.get_padding(inputs)
      inputs_attention_bias = utils.get_padding_bias(inputs)

      #inputs_attention_bias = tf.cast(utils.get_padding_bias(inputs),
      #                                dtype=self.params['dtype'])

      with tf.name_scope("add_pos_encoding"):
        length = tf.shape(embedded_inputs)[1]
        pos_encoding = utils.get_position_encoding(
            length, self.params["hidden_size"])
        encoder_inputs = embedded_inputs + tf.cast(x=pos_encoding,
                                                   dtype=embedded_inputs.dtype)

      if self.mode == "train":
        encoder_inputs = tf.nn.dropout(
            encoder_inputs, 1 - self.params["layer_postprocess_dropout"])

      encoded = self._call(encoder_inputs, inputs_attention_bias,
                           inputs_padding)
      return {'outputs': encoded,
              'inputs_attention_bias': inputs_attention_bias,
              'state': None,
              'src_lengths': input_dict['source_tensors'][1],
              'embedding_softmax_layer': self.embedding_softmax_layer,
              'encoder_input': inputs}
Beispiel #3
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    def _encode(self, input_dict):
        training = (self.mode == "train")

        if len(self.layers) == 0:
            # prepare encoder graph
            self.embedding_softmax_layer = embedding_layer.EmbeddingSharedWeights(
                self.params["src_vocab_size"],
                self.params["hidden_size"],
                pad_vocab_to_eight=self.params.get('pad_embeddings_2_eight',
                                                   False),
            )

            for _ in range(self.params['encoder_layers']):
                # Create sublayers for each layer.
                self_attention_layer = attention_layer.SelfAttention(
                    hidden_size=self.params["hidden_size"],
                    num_heads=self.params["num_heads"],
                    attention_dropout=self.params["attention_dropout"],
                    train=training,
                    regularizer=self.regularizer,
                    batch_size=self.batch_size,
                    num_feature=self.num_features)
                feed_forward_network = ffn_layer.FeedFowardNetwork(
                    hidden_size=self.params["hidden_size"],
                    filter_size=self.params["filter_size"],
                    relu_dropout=self.params["relu_dropout"],
                    train=training,
                    #num_features=self.num_features,
                    #batch_size=self.batch_size,
                    regularizer=self.regularizer)

                self.layers.append([
                    PrePostProcessingWrapper(self_attention_layer, self.params,
                                             training),
                    PrePostProcessingWrapper(feed_forward_network, self.params,
                                             training)
                ])

            # final normalization layer.
            print("Encoder:", self.norm_params["type"], self.mode)
            if self.norm_params["type"] == "batch_norm":
                self.output_normalization = Transformer_BatchNorm(
                    training=training, params=self.norm_params)
            else:
                self.output_normalization = LayerNormalization(
                    hidden_size=self.params["hidden_size"],
                    params=self.norm_params)

        # actual encoder part
        with tf.name_scope("encode"):
            inputs, src_lengths = input_dict['source_tensors']
            #inputs = input_dict['source_tensors'][0]
            # Prepare inputs to the layer stack by adding positional encodings and
            # applying dropout.
            embedded_inputs = self.embedding_softmax_layer(inputs)
            if self.params["remove_padding"]:
                inputs_padding = utils.get_padding(inputs)
                #inputs_padding = utils.get_padding(inputs,dtype=self._params["dtype"])
            else:
                inputs_padding = None
            inputs_attention_bias = utils.get_padding_bias(inputs)
            inputs_attention_bias = tf.transpose(inputs_attention_bias,
                                                 [0, 1, 3, 2, 4])
            # inputs_attention_bias = utils.get_padding_bias(inputs, dtype=self._params["dtype"])

            with tf.name_scope("add_pos_encoding"):
                length = tf.shape(embedded_inputs)[1]
                pos_encoding = utils.get_position_encoding(
                    length,
                    self.params["hidden_size"],
                )
                #encoder_inputs = embedded_inputs + tf.cast(x=pos_encoding,
                #                                           dtype=embedded_inputs.dtype)
                pos_encoding = tf.cast(x=pos_encoding,
                                       dtype=embedded_inputs.dtype)
                pos_encoding_exp = pos_encoding[None, :, None, :]
                encoder_inputs = embedded_inputs + pos_encoding_exp

            if self.mode == "train":
                encoder_inputs = tf.nn.dropout(
                    encoder_inputs,
                    keep_prob=1.0 - self.params["layer_postprocess_dropout"],
                )

            encoded = self._call(encoder_inputs, inputs_attention_bias,
                                 inputs_padding)
            return {
                'outputs': encoded,
                'inputs_attention_bias': inputs_attention_bias,
                'state': None,
                'src_lengths': src_lengths,
                #'src_lengths': input_dict['source_tensors'][1],
                'embedding_softmax_layer': self.embedding_softmax_layer,
                'encoder_input': inputs
            }