nn.Embedding(1, output_size)

`nn.Embedding(1, output_size)`是PyTorch库中的一个神经网络层，通常用于处理词嵌入（word embeddings）。它属于`torch.nn.EmbeddingBag`模块的一部分，但这里简化版本是指单维度的嵌入层，常用于单一维度的数据如标签或类别id。其中：

- `1` 表示输入维度，这里是1维的，例如只有一列特征或者是一个离散的类别值。
- `output_size` 是嵌入向量的大小，即每个输入元素（在这种情况下是个类别ID）将被转换成一个`output_size`长度的向量。这个向量通常用于捕捉输入项的复杂表示，比如词汇表中的单词可以用高维稠密向量表示。

这个层的主要作用是在模型训练过程中，将输入的整数编码（例如，索引）映射为固定长度的实数值向量，这在诸如循环神经网络（RNNs）、卷积神经网络（CNNs）等序列模型中非常常见，用于捕获输入数据的上下文信息。

相关问题

class PoetryModel(nn.Module): def init(self, vocab_size, embedding_dim, hidden_dim): super(PoetryModel, self).init() self.hidden_dim = hidden_dim self.embedding = nn.Embedding(vocab_size, embedding_dim) self.lstm = nn.LSTM(embedding_dim, self.hidden_dim, num_layers=3) self.classifier=nn.Sequential( nn.Linear(self.hidden_dim, 512), nn.ReLU(inplace=True), nn.Linear(512, 2048), nn.ReLU(inplace=True), nn.Linear(2048, vocab_size) ) def forward(self, input, hidden = None): seq_len, batch_size = input.size() if hidden is None: h_0 = input.data.new(3, batch_size, self.hidden_dim).fill_(0).float() c_0 = input.data.new(3, batch_size, self.hidden_dim).fill_(0).float() else: h_0, c_0 = hidden embeds = self.embedding(input) output, hidden = self.lstm(embeds, (h_0, c_0)) output = self.classifier(output.view(seq_len * batch_size, -1)) return output, hidden 请优化这段代码

这段代码已经写得比较好了，但是有几个可以改进的地方：

1. 在初始化函数中使用 super() 函数时，应该将 PoetryModel 类的名称作为第一个参数，而不是使用 super() 函数的默认参数。

2. 在 forward 函数中，应该使用 new_zeros() 方法来初始化 h_0 和 c_0，而不是使用 fill_() 方法。

3. 在 forward 函数中，应该使用 contiguous() 方法来确保输入的张量在内存中是连续的，这样可以加快计算速度。

改进后的代码如下所示：

class PoetryModel(nn.Module):
    def __init__(self, vocab_size, embedding_dim, hidden_dim):
        super(PoetryModel, self).__init__()
        self.hidden_dim = hidden_dim
        self.embedding = nn.Embedding(vocab_size, embedding_dim)
        self.lstm = nn.LSTM(embedding_dim, self.hidden_dim, num_layers=3)
        self.classifier = nn.Sequential(
            nn.Linear(self.hidden_dim, 512),
            nn.ReLU(inplace=True),
            nn.Linear(512, 2048),
            nn.ReLU(inplace=True),
            nn.Linear(2048, vocab_size)
        )

    def forward(self, input, hidden=None):
        seq_len, batch_size = input.size()
        if hidden is None:
            h_0 = input.data.new_zeros(3, batch_size, self.hidden_dim).float()
            c_0 = input.data.new_zeros(3, batch_size, self.hidden_dim).float()
        else:
            h_0, c_0 = hidden
        embeds = self.embedding(input)
        embeds = embeds.contiguous()
        output, hidden = self.lstm(embeds, (h_0, c_0))
        output = self.classifier(output.view(seq_len * batch_size, -1))
        return output, hidden

这个优化版本主要是将 super() 函数中的参数修改为 PoetryModel 类的名称，使用了 new_zeros() 方法初始化 h_0 和 c_0，使用了 contiguous() 方法确保输入的张量在内存中是连续的。这样可以提高代码的效率和可读性。

import torch import torch.nn as nn import torch.optim as optim import numpy as np 定义基本循环神经网络模型 class RNNModel(nn.Module): def init(self, rnn_type, input_size, hidden_size, output_size, num_layers=1): super(RNNModel, self).init() self.rnn_type = rnn_type self.input_size = input_size self.hidden_size = hidden_size self.output_size = output_size self.num_layers = num_layers self.encoder = nn.Embedding(input_size, hidden_size) if rnn_type == 'RNN': self.rnn = nn.RNN(hidden_size, hidden_size, num_layers) elif rnn_type == 'GRU': self.rnn = nn.GRU(hidden_size, hidden_size, num_layers) self.decoder = nn.Linear(hidden_size, output_size) def forward(self, input, hidden): input = self.encoder(input) output, hidden = self.rnn(input, hidden) output = output.view(-1, self.hidden_size) output = self.decoder(output) return output, hidden def init_hidden(self, batch_size): if self.rnn_type == 'RNN': return torch.zeros(self.num_layers, batch_size, self.hidden_size) elif self.rnn_type == 'GRU': return torch.zeros(self.num_layers, batch_size, self.hidden_size) 定义数据集 with open('汉语音节表.txt', encoding='utf-8') as f: chars = f.readline() chars = list(chars) idx_to_char = list(set(chars)) char_to_idx = dict([(char, i) for i, char in enumerate(idx_to_char)]) corpus_indices = [char_to_idx[char] for char in chars] 定义超参数 input_size = len(idx_to_char) hidden_size = 256 output_size = len(idx_to_char) num_layers = 1 batch_size = 32 num_steps = 5 learning_rate = 0.01 num_epochs = 100 定义模型、损失函数和优化器 model = RNNModel('RNN', input_size, hidden_size, output_size, num_layers) criterion = nn.CrossEntropyLoss() optimizer = optim.Adam(model.parameters(), lr=learning_rate) 训练模型 for epoch in range(num_epochs): model.train() hidden = model.init_hidden(batch_size) loss = 0 for X, Y in data_iter_consecutive(corpus_indices, batch_size, num_steps): optimizer.zero_grad() hidden = hidden.detach() output, hidden = model(X, hidden) loss = criterion(output, Y.view(-1)) loss.backward() torch.nn.utils.clip_grad_norm_(model.parameters(), max_norm=1.0) optimizer.step() if epoch % 10 == 0: print(f"Epoch {epoch}, Loss: {loss.item()}")请正确缩进代码

下面是正确缩进的代码：

import torch 
import torch.nn as nn 
import torch.optim as optim 
import numpy as np 

# 定义基本循环神经网络模型 
class RNNModel(nn.Module): 
    def __init__(self, rnn_type, input_size, hidden_size, output_size, num_layers=1): 
        super(RNNModel, self).__init__() 
        self.rnn_type = rnn_type 
        self.input_size = input_size 
        self.hidden_size = hidden_size 
        self.output_size = output_size 
        self.num_layers = num_layers 
        self.encoder = nn.Embedding(input_size, hidden_size) 
        if rnn_type == 'RNN': 
            self.rnn = nn.RNN(hidden_size, hidden_size, num_layers) 
        elif rnn_type == 'GRU': 
            self.rnn = nn.GRU(hidden_size, hidden_size, num_layers) 
        self.decoder = nn.Linear(hidden_size, output_size) 

    def forward(self, input, hidden): 
        input = self.encoder(input) 
        output, hidden = self.rnn(input, hidden) 
        output = output.view(-1, self.hidden_size) 
        output = self.decoder(output) 
        return output, hidden 

    def init_hidden(self, batch_size): 
        if self.rnn_type == 'RNN': 
            return torch.zeros(self.num_layers, batch_size, self.hidden_size) 
        elif self.rnn_type == 'GRU': 
            return torch.zeros(self.num_layers, batch_size, self.hidden_size) 

# 定义数据集 
with open('汉语音节表.txt', encoding='utf-8') as f: 
    chars = f.readline() 
    chars = list(chars) 
    idx_to_char = list(set(chars)) 
    char_to_idx = dict([(char, i) for i, char in enumerate(idx_to_char)]) 
    corpus_indices = [char_to_idx[char] for char in chars] 

# 定义超参数 
input_size = len(idx_to_char) 
hidden_size = 256 
output_size = len(idx_to_char) 
num_layers = 1 
batch_size = 32 
num_steps = 5 
learning_rate = 0.01 
num_epochs = 100 

# 定义模型、损失函数和优化器 
model = RNNModel('RNN', input_size, hidden_size, output_size, num_layers) 
criterion = nn.CrossEntropyLoss() 
optimizer = optim.Adam(model.parameters(), lr=learning_rate) 

# 训练模型 
for epoch in range(num_epochs): 
    model.train() 
    hidden = model.init_hidden(batch_size) 
    loss = 0 
    for X, Y in data_iter_consecutive(corpus_indices, batch_size, num_steps): 
        optimizer.zero_grad() 
        hidden = hidden.detach() 
        output, hidden = model(X, hidden) 
        loss = criterion(output, Y.view(-1)) 
        loss.backward() 
        torch.nn.utils.clip_grad_norm_(model.parameters(), max_norm=1.0) 
        optimizer.step() 
    if epoch % 10 == 0: 
        print(f"Epoch {epoch}, Loss: {loss.item()}")