我有来自 PyTorch 几何示例的以下代码片段。我想使用随着训练期间损失值的降低而降低的学习率。我尝试使用调度程序,但这对我不起作用。
下面是一个干净的代码片段。任何人都可以就此事提供宝贵的建议或帮助吗?
import torch
import torch.nn.functional as F
from torch_geometric.datasets import Planetoid
import torch_geometric.transforms as T
from torch_geometric.nn import AGNNConv
dataset = 'Cora'
path = 'Cora'
dataset = Planetoid(path, dataset, transform=T.NormalizeFeatures())
data = dataset[0]
class Net(torch.nn.Module):
def __init__(self):
super(Net, self).__init__()
self.lin1 = torch.nn.Linear(dataset.num_features, 16)
self.prop1 = AGNNConv(requires_grad=False)
self.prop2 = AGNNConv(requires_grad=True)
self.lin2 = torch.nn.Linear(16, dataset.num_classes)
def forward(self):
x = F.dropout(data.x, training=self.training)
x = F.relu(self.lin1(x))
x = self.prop1(x, data.edge_index)
x = self.prop2(x, data.edge_index)
x = F.dropout(x, training=self.training)
x = self.lin2(x)
return F.log_softmax(x, dim=1)
device = torch.device('cuda' if torch.cuda.is_available() else 'cpu')
model, data = Net().to(device), data.to(device)
optimizer = torch.optim.Adam(model.parameters(), lr=0.01, weight_decay=5e-4)
def train():
model.train()
optimizer.zero_grad()
F.nll_loss(model()[data.train_mask], data.y[data.train_mask]).backward()
optimizer.step()
def test():
model.eval()
logits, accs = model(), []
for _, mask in data('train_mask', 'val_mask', 'test_mask'):
pred = logits[mask].max(1)[1]
acc = pred.eq(data.y[mask]).sum().item() / mask.sum().item()
accs.append(acc)
return accs
best_val_acc = test_acc = 0
for epoch in range(1, 201):
train()
train_acc, val_acc, tmp_test_acc = test()
if val_acc > best_val_acc:
best_val_acc = val_acc
test_acc = tmp_test_acc
log = 'Epoch: {:03d}, Train: {:.4f}, Val: {:.4f}, Test: {:.4f}'
print(log.format(epoch, train_acc, best_val_acc, test_acc))