R = tf.keras.layers.Reshape((sequence_length, 1, 1), name='R')(input_data)
时间: 2023-10-29 21:06:22 浏览: 28
这段代码使用了 Keras 中的 Reshape 层,将输入数据的形状从 (batch_size, sequence_length, embedding_dim) 转换为 (batch_size, sequence_length, 1, 1)。其中,sequence_length 是序列的长度,embedding_dim 是词嵌入的维度。这个 Reshape 的目的可能是将数据转换为 2D 卷积网络所需要的输入形状,因为 2D 卷积网络需要的输入形状是 (batch_size, height, width, channels)。在这里,我们将 height 和 width 都设置为 1,将 channels 设置为 1,因为我们只需要对序列进行卷积,不需要考虑图像的高度和宽度。
相关问题
import tensorflow as tf import tensorflow_hub as hub from tensorflow.keras import layers import bert import numpy as np from transformers import BertTokenizer, BertModel # 设置BERT模型的路径和参数 bert_path = "E:\\AAA\\523\\BERT-pytorch-master\\bert1.ckpt" max_seq_length = 128 train_batch_size = 32 learning_rate = 2e-5 num_train_epochs = 3 # 加载BERT模型 def create_model(): input_word_ids = tf.keras.layers.Input(shape=(max_seq_length,), dtype=tf.int32, name="input_word_ids") input_mask = tf.keras.layers.Input(shape=(max_seq_length,), dtype=tf.int32, name="input_mask") segment_ids = tf.keras.layers.Input(shape=(max_seq_length,), dtype=tf.int32, name="segment_ids") bert_layer = hub.KerasLayer(bert_path, trainable=True) pooled_output, sequence_output = bert_layer([input_word_ids, input_mask, segment_ids]) output = layers.Dense(1, activation='sigmoid')(pooled_output) model = tf.keras.models.Model(inputs=[input_word_ids, input_mask, segment_ids], outputs=output) return model # 准备数据 def create_input_data(sentences, labels): tokenizer = bert.tokenization.FullTokenizer(vocab_file=bert_path + "trainer/vocab.small", do_lower_case=True) # tokenizer = BertTokenizer.from_pretrained('bert-base-uncased') input_ids = [] input_masks = [] segment_ids = [] for sentence in sentences: tokens = tokenizer.tokenize(sentence) tokens = ["[CLS]"] + tokens + ["[SEP]"] input_id = tokenizer.convert_tokens_to_ids(tokens) input_mask = [1] * len(input_id) segment_id = [0] * len(input_id) padding_length = max_seq_length - len(input_id) input_id += [0] * padding_length input_mask += [0] * padding_length segment_id += [0] * padding_length input_ids.append(input_id) input_masks.append(input_mask) segment_ids.append(segment_id) return np.array(input_ids), np.array(input_masks), np.array(segment_ids), np.array(labels) # 加载训练数据 train_sentences = ["Example sentence 1", "Example sentence 2", ...] train_labels = [0, 1, ...] train_input_ids, train_input_masks, train_segment_ids, train_labels = create_input_data(train_sentences, train_labels) # 构建模型 model = create_model() model.compile(optimizer=tf.keras.optimizers.Adam(lr=learning_rate), loss='binary_crossentropy', metrics=['accuracy']) # 开始微调 model.fit([train_input_ids, train_input_masks, train_segment_ids], train_labels, batch_size=train_batch_size, epochs=num_train_epochs)这段代码有什么问题吗?
这段代码存在一些问题:
1. `bert_path` 的值不应该是 ".ckpt" 结尾的文件路径,而是BERT模型的目录路径,例如:`bert_path = "E:\\AAA\\523\\BERT-pytorch-master\\"`。
2. `vocab_file` 参数应该是BERT模型目录下的 "vocab.txt" 文件路径,而不是训练器目录下的 "vocab.small" 文件路径。例如:`tokenizer = bert.tokenization.FullTokenizer(vocab_file=bert_path + "vocab.txt", do_lower_case=True)`。
3. `create_input_data` 函数中的 `tokenizer` 对象应该是从 `BertTokenizer` 类中导入的。因此,需要将 `from transformers import BertTokenizer` 加入代码开头,并使用 `BertTokenizer.from_pretrained()` 函数来加载BERT的tokenizer。
4. `train_sentences` 和 `train_labels` 应该是训练数据集,但是在代码中缺失了这些数据的定义和加载。
5. `create_input_data` 函数返回的 `labels` 应该是一维的,而不是二维的。因此,需要修改函数 `return` 语句为:`return np.array(input_ids), np.array(input_masks), np.array(segment_ids), np.array(labels).reshape(-1)`。
6. 在 `model.fit` 中,需要指定验证集的参数 `validation_data`,以便在训练过程中评估模型的性能。
综上所述,以下是修改后的代码示例:
```
import tensorflow as tf
import tensorflow_hub as hub
from tensorflow.keras import layers
import bert
import numpy as np
from transformers import BertTokenizer, BertModel
# 设置BERT模型的路径和参数
bert_path = "E:\\AAA\\523\\BERT-pytorch-master\\"
max_seq_length = 128
train_batch_size = 32
learning_rate = 2e-5
num_train_epochs = 3
# 加载BERT模型
def create_model():
input_word_ids = tf.keras.layers.Input(shape=(max_seq_length,), dtype=tf.int32, name="input_word_ids")
input_mask = tf.keras.layers.Input(shape=(max_seq_length,), dtype=tf.int32, name="input_mask")
segment_ids = tf.keras.layers.Input(shape=(max_seq_length,), dtype=tf.int32, name="segment_ids")
bert_layer = hub.KerasLayer(bert_path, trainable=True)
pooled_output, sequence_output = bert_layer([input_word_ids, input_mask, segment_ids])
output = layers.Dense(1, activation='sigmoid')(pooled_output)
model = tf.keras.models.Model(inputs=[input_word_ids, input_mask, segment_ids], outputs=output)
return model
# 准备数据
def create_input_data(sentences, labels):
tokenizer = BertTokenizer.from_pretrained('bert-base-uncased')
input_ids = []
input_masks = []
segment_ids = []
for sentence in sentences:
tokens = tokenizer.tokenize(sentence)
tokens = ["[CLS]"] + tokens + ["[SEP]"]
input_id = tokenizer.convert_tokens_to_ids(tokens)
input_mask = [1] * len(input_id)
segment_id = [0] * len(input_id)
padding_length = max_seq_length - len(input_id)
input_id += [0] * padding_length
input_mask += [0] * padding_length
segment_id += [0] * padding_length
input_ids.append(input_id)
input_masks.append(input_mask)
segment_ids.append(segment_id)
return np.array(input_ids), np.array(input_masks), np.array(segment_ids), np.array(labels).reshape(-1)
# 加载训练数据
train_sentences = ["Example sentence 1", "Example sentence 2", ...]
train_labels = [0, 1, ...]
train_input_ids, train_input_masks, train_segment_ids, train_labels = create_input_data(train_sentences, train_labels)
# 构建模型
model = create_model()
model.compile(optimizer=tf.keras.optimizers.Adam(lr=learning_rate),
loss='binary_crossentropy',
metrics=['accuracy'])
# 开始微调
model.fit([train_input_ids, train_input_masks, train_segment_ids], train_labels,
batch_size=train_batch_size,
epochs=num_train_epochs,
validation_data=([val_input_ids, val_input_masks, val_segment_ids], val_labels))
```
解决AttributeError: module 'tensorflow._api.v2.compat.v1.nn.rnn_cell' has no attribute 'seq2seq'
在 TensorFlow 2.0 中,`tf.nn.rnn_cell` 模块已经被移除了,因此 `tf.nn.rnn_cell.seq2seq` 也不再可用。相反,您可以使用 `tf.keras.layers` 中的相应函数来构建您的模型。下面是一个使用 `tf.keras` 实现 seq2seq 模型的示例:
``` python
import tensorflow as tf
# 定义编码器
class Encoder(tf.keras.Model):
def __init__(self, vocab_size, embedding_dim, enc_units, batch_sz):
super(Encoder, self).__init__()
self.batch_sz = batch_sz
self.enc_units = enc_units
self.embedding = tf.keras.layers.Embedding(vocab_size, embedding_dim)
self.gru = tf.keras.layers.GRU(self.enc_units, return_sequences=True, return_state=True, recurrent_initializer='glorot_uniform')
def call(self, x, hidden):
x = self.embedding(x)
output, state = self.gru(x, initial_state = hidden)
return output, state
def initialize_hidden_state(self):
return tf.zeros((self.batch_sz, self.enc_units))
# 定义注意力层
class BahdanauAttention(tf.keras.layers.Layer):
def __init__(self, units):
super(BahdanauAttention, self).__init__()
self.W1 = tf.keras.layers.Dense(units)
self.W2 = tf.keras.layers.Dense(units)
self.V = tf.keras.layers.Dense(1)
def call(self, query, values):
# query: 上一时间步的隐藏状态,shape=(batch_size, hidden_size)
# values: 编码器的输出,shape=(batch_size, max_length, hidden_size)
hidden_with_time_axis = tf.expand_dims(query, 1)
score = self.V(tf.nn.tanh(
self.W1(values) + self.W2(hidden_with_time_axis)))
# attention_weights shape == (batch_size, max_length, 1)
attention_weights = tf.nn.softmax(score, axis=1)
# context_vector shape after sum == (batch_size, hidden_size)
context_vector = attention_weights * values
context_vector = tf.reduce_sum(context_vector, axis=1)
return context_vector, attention_weights
# 定义解码器
class Decoder(tf.keras.Model):
def __init__(self, vocab_size, embedding_dim, dec_units, batch_sz):
super(Decoder, self).__init__()
self.batch_sz = batch_sz
self.dec_units = dec_units
self.embedding = tf.keras.layers.Embedding(vocab_size, embedding_dim)
self.gru = tf.keras.layers.GRU(self.dec_units, return_sequences=True, return_state=True, recurrent_initializer='glorot_uniform')
self.fc = tf.keras.layers.Dense(vocab_size)
# 用于注意力
self.attention = BahdanauAttention(self.dec_units)
def call(self, x, hidden, enc_output):
# enc_output shape == (batch_size, max_length, hidden_size)
context_vector, attention_weights = self.attention(hidden, enc_output)
# x shape after passing through embedding == (batch_size, 1, embedding_dim)
x = self.embedding(x)
# 将上一时间步的隐藏状态和注意力向量拼接起来作为输入传给 GRU
x = tf.concat([tf.expand_dims(context_vector, 1), x], axis=-1)
# 将拼接后的向量传给 GRU
output, state = self.gru(x)
# output shape == (batch_size * 1, hidden_size)
output = tf.reshape(output, (-1, output.shape[2]))
# output shape == (batch_size, vocab)
x = self.fc(output)
return x, state, attention_weights
# 定义损失函数和优化器
optimizer = tf.keras.optimizers.Adam()
loss_object = tf.keras.losses.SparseCategoricalCrossentropy(from_logits=True, reduction='none')
def loss_function(real, pred):
mask = tf.math.logical_not(tf.math.equal(real, 0))
loss_ = loss_object(real, pred)
mask = tf.cast(mask, dtype=loss_.dtype)
loss_ *= mask
return tf.reduce_mean(loss_)
# 定义训练步骤
@tf.function
def train_step(inp, targ, enc_hidden):
loss = 0
with tf.GradientTape() as tape:
enc_output, enc_hidden = encoder(inp, enc_hidden)
dec_hidden = enc_hidden
dec_input = tf.expand_dims([tokenizer.word_index['<start>']] * BATCH_SIZE, 1)
# teacher forcing - 将目标词作为下一个输入传给解码器
for t in range(1, targ.shape[1]):
# 将编码器的输出和上一时间步的隐藏状态传给解码器
predictions, dec_hidden, _ = decoder(dec_input, dec_hidden, enc_output)
loss += loss_function(targ[:, t], predictions)
# 使用 teacher forcing
dec_input = tf.expand_dims(targ[:, t], 1)
batch_loss = (loss / int(targ.shape[1]))
variables = encoder.trainable_variables + decoder.trainable_variables
gradients = tape.gradient(loss, variables)
optimizer.apply_gradients(zip(gradients, variables))
return batch_loss
# 定义预测函数
def evaluate(sentence):
attention_plot = np.zeros((max_length_targ, max_length_inp))
sentence = preprocess_sentence(sentence)
inputs = [tokenizer.word_index[i] for i in sentence.split(' ')]
inputs = tf.keras.preprocessing.sequence.pad_sequences([inputs], maxlen=max_length_inp, padding='post')
inputs = tf.convert_to_tensor(inputs)
result = ''
hidden = [tf.zeros((1, units))]
enc_out, enc_hidden = encoder(inputs, hidden)
dec_hidden = enc_hidden
dec_input = tf.expand_dims([tokenizer.word_index['<start>']], 0)
for t in range(max_length_targ):
predictions, dec_hidden, attention_weights = decoder(dec_input, dec_hidden, enc_out)
# 存储注意力权重以便后面制图
attention_weights = tf.reshape(attention_weights, (-1, ))
attention_plot[t] = attention_weights.numpy()
predicted_id = tf.argmax(predictions[0]).numpy()
result += tokenizer.index_word[predicted_id] + ' '
if tokenizer.index_word[predicted_id] == '<end>':
return result, sentence, attention_plot
# 将预测的 ID 作为下一个解码器输入的 ID
dec_input = tf.expand_dims([predicted_id], 0)
return result, sentence, attention_plot
```
在上面的代码中,我们使用了 `tf.keras.layers` 中的 `Embedding`、`GRU` 和 `Dense` 层来构建编码器和解码器,使用 `tf.keras.optimizers.Adam` 作为优化器,使用 `tf.keras.losses.SparseCategoricalCrossentropy` 作为损失函数。同时,我们还定义了一个 `BahdanauAttention` 层来实现注意力机制。