接上一篇文章
python
sentences = [
['咖哥 喜欢 小冰', 'KaGe likes XiaoBing'],
['我 爱 学习 人工智能', 'I love studying AI'],
['深度学习 改变 世界', ' DL changed the world'],
['自然语言处理 很 强大', 'NLP is powerful'],
['神经网络 非常 复杂', 'Neural-networks are complex'] ]
class TranslationCorpus:
def __init__(self, sentences):
self.sentences = sentences
# 计算源语言和目标语言的最大句子长度，并分别加 1 和 2 以容纳填充符和特殊符号
self.src_len = max(len(sentence[0].split()) for sentence in sentences) + 1
self.tgt_len = max(len(sentence[1].split()) for sentence in sentences) + 2
# 创建源语言和目标语言的词汇表
self.src_vocab, self.tgt_vocab = self.create_vocabularies()
# 创建索引到单词的映射
self.src_idx2word = {v: k for k, v in self.src_vocab.items()}
self.tgt_idx2word = {v: k for k, v in self.tgt_vocab.items()}
# 定义创建词汇表的函数
def create_vocabularies(self):
# 统计源语言和目标语言的单词频率
src_counter = Counter(word for sentence in self.sentences for word in sentence[0].split())
tgt_counter = Counter(word for sentence in self.sentences for word in sentence[1].split())
# 创建源语言和目标语言的词汇表，并为每个单词分配一个唯一的索引
src_vocab = {'<pad>': 0, **{word: i+1 for i, word in enumerate(src_counter)}}
tgt_vocab = {'<pad>': 0, '<sos>': 1, '<eos>': 2,
**{word: i+3 for i, word in enumerate(tgt_counter)}}
return src_vocab, tgt_vocab
# 定义创建批次数据的函数
def make_batch(self, batch_size, test_batch=False):
input_batch, output_batch, target_batch = [], [], []
# 随机选择句子索引
sentence_indices = torch.randperm(len(self.sentences))[:batch_size]
for index in sentence_indices:
src_sentence, tgt_sentence = self.sentences[index]
# 将源语言和目标语言的句子转换为索引序列
src_seq = [self.src_vocab[word] for word in src_sentence.split()]
tgt_seq = [self.tgt_vocab['<sos>']] + [self.tgt_vocab[word] \
for word in tgt_sentence.split()] + [self.tgt_vocab['<eos>']]
# 对源语言和目标语言的序列进行填充
src_seq += [self.src_vocab['<pad>']] * (self.src_len - len(src_seq))
tgt_seq += [self.tgt_vocab['<pad>']] * (self.tgt_len - len(tgt_seq))
# 将处理好的序列添加到批次中
input_batch.append(src_seq)
output_batch.append([self.tgt_vocab['<sos>']] + ([self.tgt_vocab['<pad>']] * \
(self.tgt_len - 2)) if test_batch else tgt_seq[:-1])
target_batch.append(tgt_seq[1:])
# 将批次转换为 LongTensor 类型
input_batch = torch.LongTensor(input_batch)
output_batch = torch.LongTensor(output_batch)
target_batch = torch.LongTensor(target_batch)
return input_batch, output_batch, target_batch
# 创建语料库类实例
corpus = TranslationCorpus(sentences)
#训练
import torch # 导入 torch
import torch.optim as optim # 导入优化器
model = Transformer(corpus) # 创建模型实例
criterion = nn.CrossEntropyLoss() # 损失函数
optimizer = optim.Adam(model.parameters(), lr=0.00001) # 优化器
epochs = 1 # 训练轮次
for epoch in range(epochs): # 训练 100 轮
optimizer.zero_grad() # 梯度清零
enc_inputs, dec_inputs, target_batch = corpus.make_batch(batch_size) # 创建训练数据
print(enc_inputs, dec_inputs, target_batch)
outputs, _, _, _ = model(enc_inputs, dec_inputs) # 获取模型输出
loss = criterion(outputs.view(-1, len(corpus.tgt_vocab)), target_batch.view(-1)) # 计算损失
if (epoch + 1) % 1 == 0: # 打印损失
print(f"Epoch: {epoch + 1:04d} cost = {loss:.6f}")
loss.backward()# 反向传播
optimizer.step()# 更新参数
#预测
# 创建一个大小为 1 的批次，目标语言序列 dec_inputs 在测试阶段，仅包含句子开始符号 <sos>
enc_inputs, dec_inputs, target_batch = corpus.make_batch(batch_size=1,test_batch=True)
# enc_inputs=torch.tensor([[14, 15, 16, 0, 0]])
dec_inputs=torch.tensor([[1, 0, 0, 0, 0]])
outt=1
for i in range(5):
dec_inputs[0][i]=outt
print("+++",i,dec_inputs[0][i],dec_inputs,outt)
predict, enc_self_attns, dec_self_attns, dec_enc_attns = model(enc_inputs, dec_inputs) # 用模型进行翻译
predict = predict.view(-1, len(corpus.tgt_vocab)) # 将预测结果维度重塑
predict = predict.data.max(1, keepdim=True)[1] # 找到每个位置概率最大的词汇的索引
print(predict)
outt=predict[i].item()
print("编码器输入 :", enc_inputs) # 打印编码器输入
print("解码器输入 :", dec_inputs) # 打印解码器输入
print("目标数据 :", target_batch) # 打印目标数据
predict, enc_self_attns, dec_self_attns, dec_enc_attns = model(enc_inputs, dec_inputs) # 用模型进行翻译
print(predict.data.max(-1))
predict = predict.view(-1, len(corpus.tgt_vocab)) # 将预测结果维度重塑
predict = predict.data.max(1, keepdim=True)[1] # 找到每个位置概率最大的词汇的索引
# 解码预测的输出，将所预测的目标句子中的索引转换为单词
translated_sentence = [corpus.tgt_idx2word[idx.item()] for idx in predict.squeeze()]
# 将输入的源语言句子中的索引转换为单词
input_sentence = ' '.join([corpus.src_idx2word[idx.item()] for idx in enc_inputs[0]])
print(input_sentence, '->', translated_sentence) # 打印原始句子和翻译后的句子