对一组非图像的拓扑图(bin文件,格式为coo)进行训练,图一共有60000左右(即60000多个bin文件),使用VGAE,代码示例
时间: 2024-03-01 12:52:35 浏览: 119
好的,针对您的问题,我可以给出以下步骤和示例代码:
步骤1:准备数据
首先,您需要将您的拓扑图数据转换为网络邻接矩阵的形式。在这个矩阵中,每个节点都对应一个编号,而每个非零元素表示两个节点之间存在一条边。您可以使用类似于以下的代码将您的数据转换为邻接矩阵的形式:
```
import numpy as np
# Load data from .bin files
data = np.fromfile('data.bin', dtype=np.int32)
# Construct adjacency matrix
num_nodes = int(np.sqrt(data.shape[0]))
adj_matrix = np.zeros((num_nodes, num_nodes))
for i in range(num_nodes):
for j in range(num_nodes):
if data[i * num_nodes + j] == 1:
adj_matrix[i, j] = 1
```
步骤2:定义模型
接下来,您需要定义 VGAE 模型。VGAE 是一种基于图卷积神经网络(GCN)的模型,它可以学习到节点的低维嵌入以及重构图。以下是一个简单的 VGAE 模型的示例代码:
```
import torch
import torch.nn as nn
import torch.nn.functional as F
from torch_geometric.nn import GCNConv
class VGAE(nn.Module):
def __init__(self, num_nodes, hidden_dim, latent_dim):
super(VGAE, self).__init__()
self.num_nodes = num_nodes
self.hidden_dim = hidden_dim
self.latent_dim = latent_dim
self.conv1 = GCNConv(num_nodes, hidden_dim)
self.conv_mu = GCNConv(hidden_dim, latent_dim)
self.conv_logvar = GCNConv(hidden_dim, latent_dim)
def encode(self, x, adj):
hidden = F.relu(self.conv1(x, adj))
return self.conv_mu(hidden, adj), self.conv_logvar(hidden, adj)
def reparameterize(self, mu, logvar):
if self.training:
std = torch.exp(0.5 * logvar)
eps = torch.randn_like(std)
return eps.mul(std).add_(mu)
else:
return mu
def decode(self, z):
return torch.matmul(z, z.t())
def forward(self, x, adj):
mu, logvar = self.encode(x, adj)
z = self.reparameterize(mu, logvar)
adj_recon = self.decode(z)
return adj_recon, mu, logvar
```
步骤3:训练模型
定义好模型之后,您需要编写训练代码。以下是一个简单的训练循环的示例代码:
```
import torch.optim as optim
# Hyperparameters
num_nodes = 60000
hidden_dim = 64
latent_dim = 16
lr = 0.01
epochs = 100
# Prepare data
adj_matrix = torch.tensor(adj_matrix, dtype=torch.float32)
x = torch.eye(num_nodes)
# Initialize model and optimizer
model = VGAE(num_nodes, hidden_dim, latent_dim)
optimizer = optim.Adam(model.parameters(), lr=lr)
# Training loop
for epoch in range(epochs):
optimizer.zero_grad()
adj_recon, mu, logvar = model(x, adj_matrix)
recon_loss = F.binary_cross_entropy_with_logits(adj_recon, adj_matrix)
kl_loss = -0.5 * torch.sum(1 + logvar - mu.pow(2) - logvar.exp())
loss = recon_loss + kl_loss
loss.backward()
optimizer.step()
print("Epoch {}, Loss: {:.4f}".format(epoch+1, loss.item()))
```
在训练过程中,我们首先计算重构误差(recon_loss)和 KL 散度(kl_loss),然后将它们加在一起得到总的损失(loss)。最后,通过反向传播更新模型参数。
希望这些代码能够对您有所帮助!
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