Ejemplo n.º 1
0
    def __init__(self, input_size=1024, context_size=1024, hidden_size=1024,
                 num_layers=1, batch_first=False, dropout=0.2,
                 init_weight=0.1):
        """
        Constructor for the RecurrentAttention.

        :param input_size: number of features in input tensor
        :param context_size: number of features in output from encoder
        :param hidden_size: internal hidden size
        :param num_layers: number of layers in LSTM
        :param batch_first: if True the model uses (batch,seq,feature) tensors,
            if false the model uses (seq, batch, feature)
        :param dropout: probability of dropout (on input to LSTM layer)
        :param init_weight: range for the uniform initializer
        """

        super(RecurrentAttention, self).__init__()

        self.rnn = nn.LSTM(input_size, hidden_size, num_layers, bias=True,
                           batch_first=batch_first)
        init_lstm_(self.rnn, init_weight)

        self.attn = BahdanauAttention(hidden_size, context_size, context_size,
                                      normalize=True, batch_first=batch_first)

        self.dropout = nn.Dropout(dropout)
Ejemplo n.º 2
0
    def __init__(self,
                 vocab_size,
                 hidden_size=1024,
                 num_layers=4,
                 dropout=0.2,
                 batch_first=False,
                 embedder=None,
                 init_weight=0.1,
                 fusion=True):
        """
        Constructor of the ResidualRecurrentDecoder.

        :param vocab_size: size of vocabulary
        :param hidden_size: hidden size for LSMT layers
        :param num_layers: number of LSTM layers
        :param dropout: probability of dropout (on input to LSTM layers)
        :param batch_first: if True the model uses (batch,seq,feature) tensors,
            if false the model uses (seq, batch, feature)
        :param embedder: instance of nn.Embedding, if None constructor will
            create new embedding layer
        :param init_weight: range for the uniform initializer
        """
        super(ResidualRecurrentDecoder, self).__init__()

        self.num_layers = num_layers

        self.att_rnn = RecurrentAttention(hidden_size,
                                          hidden_size,
                                          hidden_size,
                                          num_layers=1,
                                          batch_first=batch_first,
                                          dropout=dropout,
                                          fusion=fusion)

        self.rnn_layers = nn.ModuleList()
        for _ in range(num_layers - 1):
            self.rnn_layers.append(
                nn.LSTM(2 * hidden_size,
                        hidden_size,
                        num_layers=1,
                        bias=True,
                        batch_first=batch_first))

        for lstm in self.rnn_layers:
            init_lstm_(lstm, init_weight)

        if embedder is not None:
            self.embedder = embedder
        else:
            self.embedder = nn.Embedding(vocab_size,
                                         hidden_size,
                                         padding_idx=config.PAD)
            nn.init.uniform_(self.embedder.weight.data, -init_weight,
                             init_weight)

        self.classifier = Classifier(hidden_size, vocab_size)
        self.dropout = nn.Dropout(p=dropout)
Ejemplo n.º 3
0
    def __init__(self, vocab_size, hidden_size=1024, num_layers=4, dropout=0.2,
                 batch_first=False, embedder=None, init_weight=0.1):
        """
        Constructor for the ResidualRecurrentEncoder.

        :param vocab_size: size of vocabulary
        :param hidden_size: hidden size for LSTM layers
        :param num_layers: number of LSTM layers, 1st layer is bidirectional
        :param dropout: probability of dropout (on input to LSTM layers)
        :param batch_first: if True the model uses (batch,seq,feature) tensors,
            if false the model uses (seq, batch, feature)
        :param embedder: instance of nn.Embedding, if None constructor will
            create new embedding layer
        :param init_weight: range for the uniform initializer
        """
        super(ResidualRecurrentEncoder, self).__init__()
        self.batch_first = batch_first
        self.rnn_layers = nn.ModuleList()
        # 1st LSTM layer, bidirectional
        self.rnn_layers.append(
            EmuBidirLSTM(hidden_size, hidden_size, num_layers=1, bias=True,
                         batch_first=batch_first, bidirectional=True))

        # 2nd LSTM layer, with 2x larger input_size
        self.rnn_layers.append(
            nn.LSTM((2 * hidden_size), hidden_size, num_layers=1, bias=True,
                    batch_first=batch_first))

        # Remaining LSTM layers
        for _ in range(num_layers - 2):
            self.rnn_layers.append(
                nn.LSTM(hidden_size, hidden_size, num_layers=1, bias=True,
                        batch_first=batch_first))

        init_lstm_(self.rnn_layers[0].bidir)
        for lstm in self.rnn_layers[1:]:
            init_lstm_(lstm)

        self.dropout = nn.Dropout(p=dropout)

        self.share_embedding = (embedder is not None)
        if embedder is not None:
            self.embedder = embedder
        else:
            self.embedder = nn.Embedding(vocab_size, hidden_size,
                                         padding_idx=config.PAD)
            nn.init.uniform_(self.embedder.weight.data, -init_weight, init_weight)