用TensorFlow搭建一个LSTM框架,含有注意力机制
时间: 2024-01-12 09:15:18 浏览: 66
cnn-bilstm-attention-time-series-prediction_keras-master
好的,以下是用TensorFlow搭建一个带有注意力机制的LSTM框架的代码:
```python
import tensorflow as tf
class AttentionLSTM(tf.keras.Model):
def __init__(self, hidden_size, attention_size):
super(AttentionLSTM, self).__init__()
self.hidden_size = hidden_size
self.attention_size = attention_size
# LSTM layer
self.lstm = tf.keras.layers.LSTM(self.hidden_size, return_sequences=True, return_state=True)
# Attention layer
self.attention_W = tf.keras.layers.Dense(self.attention_size)
self.attention_U = tf.keras.layers.Dense(self.attention_size)
self.attention_v = tf.keras.layers.Dense(1)
# Output layer
self.output_layer = tf.keras.layers.Dense(1, activation='sigmoid')
def call(self, inputs, hidden_state, cell_state):
# LSTM layer
lstm_output, last_hidden_state, last_cell_state = self.lstm(inputs, initial_state=[hidden_state, cell_state])
# Attention layer
attention_score = self.attention_v(tf.nn.tanh(self.attention_W(lstm_output) + self.attention_U(last_hidden_state)))
attention_weights = tf.nn.softmax(attention_score, axis=1)
attention_output = tf.reduce_sum(attention_weights * lstm_output, axis=1)
# Output layer
output = self.output_layer(attention_output)
return output, last_hidden_state, last_cell_state
```
这个模型有一个LSTM层、一个注意力层和一个输出层。在调用模型的时候,需要传入LSTM的输入序列、上一个时间步的隐藏状态和细胞状态。模型会返回当前时间步的输出、当前时间步的隐藏状态和细胞状态。在这个模型中,注意力机制是通过一个Dense层实现的。首先,用这个Dense层将LSTM输出的每个时间步的向量转换成一个注意力分数,然后用softmax函数将这些分数归一化,得到每个时间步的注意力权重。最后,将这些权重和对应的LSTM输出向量相乘,得到注意力输出。
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