用python编程实现下面的内容:使用循环神经网络学习汉语拼音的拼写本次实验重点为准备数据和模型。1拼音数据无声调:httpswwwjianguoyuncompDQ3els0Q-rqYBhi3pIgFIAA2定义数据集:采用字符模型因此一个字符为一个样本。每个样本采用one-hot编码。3样本是时间相关的分别实现序列的随机采样和序列的顺序划分4标签Y与X同形状但时间超前15准备数据:一次梯度更新
由于涉及到数据集的下载,无法在此直接提供完整代码。以下是大致的实现步骤和代码框架。
- 下载拼音数据,并解压缩到指定路径下:
import zipfile
with zipfile.ZipFile('path/to/pinyin_data.zip', 'r') as zip_ref:
zip_ref.extractall('path/to/pinyin_data')
- 定义数据集:
import os
import numpy as np
data_dir = 'path/to/pinyin_data'
file_names = os.listdir(data_dir)
char_list = ['<PAD>', '<EOS>', '<UNK>'] + sorted(list(set(''.join([open(os.path.join(data_dir, f), 'r', encoding='utf-8').read() for f in file_names]))))
char2idx = {c: i for i, c in enumerate(char_list)}
idx2char = {i: c for c, i in char2idx.items()}
num_classes = len(char_list)
def encode_one_hot(char):
one_hot = np.zeros(num_classes)
one_hot[char2idx.get(char, char2idx['<UNK>'])] = 1
return one_hot
def decode_one_hot(one_hot):
return idx2char[np.argmax(one_hot)]
def load_data(file_names):
data = []
for f in file_names:
with open(os.path.join(data_dir, f), 'r', encoding='utf-8') as file:
text = file.read().strip()
for i in range(len(text)):
if i == 0:
data.append([encode_one_hot('<EOS>'), encode_one_hot(text[i])])
else:
data.append([encode_one_hot(text[i-1]), encode_one_hot(text[i])])
return data
- 实现随机采样和序列划分:
def get_batch(data, batch_size, time_steps, shuffle=True):
if shuffle:
np.random.shuffle(data)
num_batches = len(data) // (batch_size * time_steps)
for i in range(num_batches):
batch_data = data[i*batch_size*time_steps:(i+1)*batch_size*time_steps]
x = [batch_data[j][0] for j in range(batch_size*time_steps)]
y = [batch_data[j][1] for j in range(batch_size*time_steps)]
yield np.array(x).reshape(batch_size, time_steps, num_classes), np.array(y).reshape(batch_size, time_steps, num_classes)
def get_batch_seq(data, batch_size, time_steps, shuffle=True):
num_seqs = len(data) // time_steps
if shuffle:
np.random.shuffle(data)
for i in range(num_seqs // batch_size):
sequences = data[i*batch_size:(i+1)*batch_size*time_steps]
x = [sequences[j:j+time_steps-1] for j in range(0, batch_size*time_steps, time_steps)]
y = [sequences[j+1:j+time_steps] for j in range(0, batch_size*time_steps, time_steps)]
yield np.array(x).transpose(1, 0, 2), np.array(y).transpose(1, 0, 2)
- 定义模型:
import torch
import torch.nn as nn
class RNNModel(nn.Module):
def __init__(self, input_size, hidden_size, output_size, num_layers, rnn_type='rnn'):
super(RNNModel, self).__init__()
self.rnn_type = rnn_type
self.hidden_size = hidden_size
self.num_layers = num_layers
self.rnn = nn.RNN(input_size, hidden_size, num_layers, batch_first=True)
self.fc = nn.Linear(hidden_size, output_size)
def forward(self, x, hidden=None):
if hidden is None:
hidden = self.init_hidden(x.size(0))
output, hidden = self.rnn(x, hidden)
output = self.fc(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)
- 训练模型:
# 定义超参数
batch_size = 32
time_steps = 10
hidden_size = 128
num_layers = 2
learning_rate = 0.001
num_epochs = 100
# 加载数据集
data = load_data(file_names)
num_samples = len(data)
# 定义模型、损失函数和优化器
model = RNNModel(num_classes, hidden_size, num_classes, num_layers)
criterion = nn.CrossEntropyLoss()
optimizer = torch.optim.Adam(model.parameters(), lr=learning_rate)
# 训练模型
for epoch in range(num_epochs):
total_loss = 0
num_batches = 0
for x, y in get_batch(data, batch_size, time_steps):
optimizer.zero_grad()
output, _ = model(torch.Tensor(x))
loss = criterion(output.view(-1, num_classes), torch.argmax(torch.Tensor(y), dim=2).view(-1))
loss.backward()
torch.nn.utils.clip_grad_norm_(model.parameters(), max_norm=5)
optimizer.step()
total_loss += loss.item()
num_batches += 1
print('Epoch [{}/{}], Loss: {:.4f}'.format(epoch+1, num_epochs, total_loss/num_batches))
- 预测模型:
def predict(model, prefix, k=1):
hidden = model.init_hidden(1)
x = torch.Tensor([encode_one_hot('<EOS>')])
for char in prefix:
output, hidden = model(x.unsqueeze(0), hidden)
x = torch.Tensor([encode_one_hot(char)])
result = prefix
for i in range(k):
output, hidden = model(x.unsqueeze(0), hidden)
pred = decode_one_hot(output.squeeze().detach().numpy())
result += pred
x = torch.Tensor([encode_one_hot(pred)])
return result
``
原文地址: https://www.cveoy.top/t/topic/ftuw 著作权归作者所有。请勿转载和采集!