Keras seq2seq -字嵌入

Question

我正在研究一个基于Keras中seq2seq的生成式聊天机器人。我使用了这个站点的代码：https://machinelearningmastery.com/develop-encoder-decoder-model-sequence-sequence-prediction-keras/

我的模特看起来是这样的：

# define training encoder
encoder_inputs = Input(shape=(None, n_input))
encoder = LSTM(n_units, return_state=True)
encoder_outputs, state_h, state_c = encoder(encoder_inputs)
encoder_states = [state_h, state_c]

# define training decoder
decoder_inputs = Input(shape=(None, n_output))
decoder_lstm = LSTM(n_units, return_sequences=True, return_state=True)
decoder_outputs, _, _ = decoder_lstm(decoder_inputs, initial_state=encoder_states)
decoder_dense = Dense(n_output, activation='softmax')
decoder_outputs = decoder_dense(decoder_outputs)
model = Model([encoder_inputs, decoder_inputs], decoder_outputs)

# define inference encoder
encoder_model = Model(encoder_inputs, encoder_states)

# define inference decoder
decoder_state_input_h = Input(shape=(n_units,))
decoder_state_input_c = Input(shape=(n_units,))
decoder_states_inputs = [decoder_state_input_h, decoder_state_input_c]
decoder_outputs, state_h, state_c = decoder_lstm(decoder_inputs, initial_state=decoder_states_inputs)
decoder_states = [state_h, state_c]
decoder_outputs = decoder_dense(decoder_outputs)
decoder_model = Model([decoder_inputs] + decoder_states_inputs [decoder_outputs] + decoder_states)

这个神经网络被设计为与一个热编码向量一起工作，这个网络的输入看起来如下：

[[[0. 0. 0. 0. 1. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.
   0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.
   0. 0. 0. 0. 0.]
  [0. 0. 0. 0. 0. 0. 0. 1. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.
   0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.
   0. 0. 0. 0. 0.]
  [0. 0. 1. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.
   0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.
   0. 0. 0. 0. 0.]]
  [[0. 0. 0. 0. 1. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.
   0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.
   0. 0. 0. 0. 0.]
  [0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 1. 0. 0. 0.
   0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.
   0. 0. 0. 0. 0.]
  [0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 1. 0. 0. 0.
   0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.
   0. 0. 0. 0. 0.]]]

我怎样才能重建这些模型来使用文字呢？我想使用字嵌入层，但我不知道如何将嵌入层连接到这些模型。

我的输入应该是[[1,5,6,7,4], [4,5,7,5,4], [7,5,4,2,1]]，其中int数是单词的表示。

我什么都试过了，但还是有错误。你能帮帮我吗？

Answer 1

我终于做到了。以下是代码：

Shared_Embedding = Embedding(output_dim=embedding, input_dim=vocab_size, name="Embedding")

encoder_inputs = Input(shape=(sentenceLength,), name="Encoder_input")
encoder = LSTM(n_units, return_state=True, name='Encoder_lstm') 
word_embedding_context = Shared_Embedding(encoder_inputs) 
encoder_outputs, state_h, state_c = encoder(word_embedding_context) 
encoder_states = [state_h, state_c] 
decoder_lstm = LSTM(n_units, return_sequences=True, return_state=True, name="Decoder_lstm")

decoder_inputs = Input(shape=(sentenceLength,), name="Decoder_input")
word_embedding_answer = Shared_Embedding(decoder_inputs) 
decoder_outputs, _, _ = decoder_lstm(word_embedding_answer, initial_state=encoder_states) 
decoder_dense = Dense(vocab_size, activation='softmax', name="Dense_layer") 
decoder_outputs = decoder_dense(decoder_outputs) 

model = Model([encoder_inputs, decoder_inputs], decoder_outputs)

encoder_model = Model(encoder_inputs, encoder_states) 

decoder_state_input_h = Input(shape=(n_units,), name="H_state_input") 
decoder_state_input_c = Input(shape=(n_units,), name="C_state_input") 
decoder_states_inputs = [decoder_state_input_h, decoder_state_input_c] 
decoder_outputs, state_h, state_c = decoder_lstm(word_embedding_answer, initial_state=decoder_states_inputs) 
decoder_states = [state_h, state_c] 
decoder_outputs = decoder_dense(decoder_outputs)

decoder_model = Model([decoder_inputs] + decoder_states_inputs, [decoder_outputs] + decoder_states)

“模型”是训练模型，encoder_model和decoder_model是推理模型。

Answer 2

在下面这个示例的FAQ部分中，它们提供了一个如何在seq2seq中使用嵌入式的示例。我目前正在自己找出推理步骤。我收到后会在这里发邮件。https://blog.keras.io/a-ten-minute-introduction-to-sequence-to-sequence-learning-in-keras.html