def test(self, dataset: BaseADDataset, ae_net: BaseNet):
logger = logging.getLogger()
# Set device for network
ae_net = ae_net.to(self.device)
# Get test data loader
_, test_loader = dataset.loaders(batch_size=self.batch_size, num_workers=self.n_jobs_dataloader)
# Testing
logger.info('Testing autoencoder...')
loss_epoch = 0.0
n_batches = 0
start_time = time.time()
idx_label_score = []
ae_net.eval()
with torch.no_grad():
for data in test_loader:
inputs, labels, idx = data
inputs = inputs.to(self.device)
outputs = ae_net(inputs)
#scores = torch.sum((outputs - inputs) ** 2, dim=tuple(range(1, outputs.dim())))
scores = bidirectional_score(inputs, outputs)
loss = torch.mean(scores)
# Save triple of (idx, label, score) in a list
idx_label_score += list(zip(idx.cpu().data.numpy().tolist(),
labels.cpu().data.numpy().tolist(),
scores.cpu().data.numpy().tolist()))
loss_epoch += loss.item()
n_batches += 1
def train(self, dataset: BaseADDataset, ae_net: BaseNet):
logger = logging.getLogger()
# Set device for network
ae_net = ae_net.to(self.device)
# Get train data loader
train_loader, _ = dataset.loaders(batch_size=self.batch_size, num_workers=self.n_jobs_dataloader)
# Set optimizer (Adam optimizer for now)
optimizer = optim.Adam(ae_net.parameters(), lr=self.lr, weight_decay=self.weight_decay,
amsgrad=self.optimizer_name == 'amsgrad')
# Set learning rate scheduler
scheduler = optim.lr_scheduler.MultiStepLR(optimizer, milestones=self.lr_milestones, gamma=0.1)
# Training
logger.info('Starting pretraining...')
start_time = time.time()
ae_net.train()
for epoch in range(self.n_epochs):
scheduler.step()
if epoch in self.lr_milestones:
logger.info(' LR scheduler: new learning rate is %g' % float(scheduler.get_lr()[0]))
loss_epoch = 0.0
n_batches = 0
epoch_start_time = time.time()
for data in train_loader:
inputs, _, _ = data
inputs = inputs.to(self.device)
# Zero the network parameter gradients
optimizer.zero_grad()
# Update network parameters via backpropagation: forward + backward + optimize
outputs = ae_net(inputs)
#scores = torch.sum((outputs - inputs) ** 2, dim=tuple(range(1, outputs.dim())))
scores = bidirectional_score(inputs, outputs)
loss = torch.mean(scores)
loss.backward()
optimizer.step()
loss_epoch += loss.item()
n_batches += 1
# log epoch statistics
epoch_train_time = time.time() - epoch_start_time
logger.info(' Epoch {}/{}\t Time: {:.3f}\t Loss: {:.8f}'
.format(epoch + 1, self.n_epochs, epoch_train_time, loss_epoch / n_batches))
pretrain_time = time.time() - start_time
logger.info('Pretraining time: %.3f' % pretrain_time)
logger.info('Finished pretraining.')
return ae_net
def test(self, dataset: BaseADDataset, net: BaseNet):
logger = logging.getLogger()
# Set device for network
net = net.to(self.device)
# Get test data loader
_, test_loader = dataset.loaders(batch_size=self.batch_size,
num_workers=self.n_jobs_dataloader)
# Testing
logger.info('Starting testing...')
start_time = time.time()
idx_label_score = []
net.eval()
with torch.no_grad():
for data in test_loader:
# 这里的label全部都是0和1,其中,1的比例占9份,0的比例占1份,这正好符合
# 另外测试的时候并没有打乱数据,数据是按照index的0开始的顺序排列的.
inputs, labels, idx = data
inputs = inputs.to(self.device)
# 对下面几句代码的解释
# output的输出为[128,32],其中128是batch的大小,32是网络的输出
# self.c大小是[32]
# 经过torch.sum之后,dist等于是将所有的output加了起来.变为了dist的大小为[128],作为输出的score
outputs = net(inputs)
dist = torch.sum((outputs - self.c)**2, dim=1)
if self.objective == 'soft-boundary':
scores = dist - self.R**2
else:
scores = dist
# 这里是将数据整合成元组
# Save triples of (idx, label, score) in a list
idx_label_score += list(
zip(idx.cpu().data.numpy().tolist(),
labels.cpu().data.numpy().tolist(),
scores.cpu().data.numpy().tolist()))
self.test_time = time.time() - start_time
logger.info('Testing time: %.3f' % self.test_time)
# 这个idx_label_score整合之后,数据的序列是按照index的顺序排列的.
self.test_scores = idx_label_score
# Compute AUC
# labels里面是0和1,scores是网络输出的scores
_, labels, scores = zip(*idx_label_score)
labels = np.array(labels)
scores = np.array(scores)
# 这个函数计算的是一个面积,他并不是按照预测的scores是不是大于0.5来看的,是要计算一个面积的.具体看我的笔记
self.test_auc = roc_auc_score(labels, scores)
logger.info('Test set AUC: {:.2f}%'.format(100. * self.test_auc))
logger.info('Finished testing.')
def test(self, dataset: BaseADDataset, ae_net: BaseNet):
logger = logging.getLogger()
# Set device for network
ae_net = ae_net.to(self.device)
# Get test data loader
_, test_loader = dataset.loaders(batch_size=self.batch_size,
num_workers=self.n_jobs_dataloader)
# Testing
logger.info('Testing autoencoder...')
loss_epoch = 0.0
n_batches = 0
start_time = time.time()
idx_label_score = []
ae_net.eval()
with torch.no_grad():
for data in test_loader:
inputs, labels, idx = data
inputs = inputs.to(self.device)
outputs = ae_net(inputs)
scores = torch.sum((outputs - inputs)**2,
dim=tuple(range(1, outputs.dim())))
loss = torch.mean(scores)
# Save triple of (idx, label, score) in a list
idx_label_score += list(
zip(idx.cpu().data.numpy().tolist(),
labels.cpu().data.numpy().tolist(),
scores.cpu().data.numpy().tolist()))
loss_epoch += loss.item()
n_batches += 1
logger.info('Test set Loss: {:.8f}'.format(loss_epoch / n_batches))
_, labels, scores = zip(*idx_label_score)
labels = np.array(labels)
scores = np.array(scores)
auc = roc_auc_score(labels, scores)
logger.info('Test set AUC: {:.2f}%'.format(100. * auc))
test_time = time.time() - start_time
logger.info('Autoencoder testing time: %.3f' % test_time)
logger.info('Finished testing autoencoder.')
def test(self, dataset: BaseADDataset, net: BaseNet):
logger = logging.getLogger()
# Set device for network
net = net.to(self.device)
# Get test data loader
_, test_loader = dataset.loaders(batch_size=self.batch_size,
num_workers=self.n_jobs_dataloader)
# Testing
logger.info('Starting testing...')
start_time = time.time()
idx_label_score = []
net.eval()
with torch.no_grad():
for data in test_loader:
inputs, labels, idx = data
inputs = inputs.to(self.device)
outputs = net(inputs)
dist = torch.sum((outputs - self.c)**2, dim=1)
if self.objective == 'soft-boundary':
scores = dist - self.R**2
else:
scores = dist
# Save triples of (idx, label, score) in a list
idx_label_score += list(
zip(idx.cpu().data.numpy().tolist(),
labels.cpu().data.numpy().tolist(),
scores.cpu().data.numpy().tolist()))
self.test_time = time.time() - start_time
logger.info('Testing time: %.3f' % self.test_time)
self.test_scores = idx_label_score
# Compute AUC
_, labels, scores = zip(*idx_label_score)
labels = np.array(labels)
scores = np.array(scores)
self.test_auc = roc_auc_score(labels, scores)
logger.info('Test set AUC: {:.2f}%'.format(100. * self.test_auc))
logger.info('Finished testing.')
def train(self, dataset: BaseADDataset, net: BaseNet):
logger = logging.getLogger()
# Set device for network
net = net.to(self.device)
# Get train data loader
train_loader, _ = dataset.loaders(batch_size=self.batch_size,
num_workers=self.n_jobs_dataloader)
# Set optimizer (Adam optimizer for now)
optimizer = optim.Adam(net.parameters(),
lr=self.lr,
weight_decay=self.weight_decay,
amsgrad=self.optimizer_name == 'amsgrad')
# Set learning rate scheduler
scheduler = optim.lr_scheduler.MultiStepLR(
optimizer, milestones=self.lr_milestones, gamma=0.1)
# Initialize hypersphere center c (if c not loaded)
if self.c is None:
logger.info('Initializing center c...')
# 需要注意的是,这里的c是针对网络的最后一层输出的每一个cell都有一个center
# 另外,这个c是不随着网络更新的,只是在最开始的时候生成一次,这就导致前面的autoencoder一定要进行了咯?????
self.c = self.init_center_c(train_loader, net)
logger.info('Center c initialized.')
# 这里计算的c是32的大小,这个程序的batchsize是200
# Training
logger.info('Starting training...')
start_time = time.time()
net.train()
for epoch in range(self.n_epochs):
scheduler.step()
if epoch in self.lr_milestones:
logger.info(' LR scheduler: new learning rate is %g' %
float(scheduler.get_lr()[0]))
loss_epoch = 0.0
n_batches = 0
epoch_start_time = time.time()
for data in train_loader:
# 第一个是所有的图片,第二个是图片对应的label,这里每个的label都是0,第三个是这个图片在数据集中对应的index
inputs, _, _ = data
inputs = inputs.to(self.device)
# Zero the network parameter gradients
optimizer.zero_grad()
# Update network parameters via backpropagation: forward + backward + optimize
outputs = net(inputs)
# 得到的outputs是[200,32]七种200是batch的大小
# 相当于求每个batch里面，这32个的和
# dist大小是200，相当于是这是一个32维的空间，求一个样本到圆心的距离的时候是每一维的距离平方然后求和
# 最后对dist的mean反映了公式里面，对n个样本，进行求平均值
# 这里就对应论文里面的loss了
dist = torch.sum((outputs - self.c)**2, dim=1)
if self.objective == 'soft-boundary':
scores = dist - self.R**2
loss = self.R**2 + (1 / self.nu) * torch.mean(
torch.max(torch.zeros_like(scores), scores))
else:
# 对应我需要的情况
loss = torch.mean(dist)
loss.backward()
optimizer.step()
# Update hypersphere radius R on mini-batch distances
if (self.objective == 'soft-boundary') and (
epoch >= self.warm_up_n_epochs):
self.R.data = torch.tensor(get_radius(dist, self.nu),
device=self.device)
loss_epoch += loss.item()
n_batches += 1
# log epoch statistics
epoch_train_time = time.time() - epoch_start_time
logger.info(' Epoch {}/{}\t Time: {:.3f}\t Loss: {:.8f}'.format(
epoch + 1, self.n_epochs, epoch_train_time,
loss_epoch / n_batches))
self.train_time = time.time() - start_time
logger.info('Training time: %.3f' % self.train_time)
logger.info('Finished training.')
return net
def train(self, dataset: BaseADDataset, net: BaseNet):
logger = logging.getLogger()
# Set device for network
net = net.to(self.device)
# Get train data loader
train_loader, _ = dataset.loaders(batch_size=self.batch_size,
num_workers=self.n_jobs_dataloader)
# Set optimizer (Adam optimizer for now)
optimizer = optim.Adam(net.parameters(),
lr=self.lr,
weight_decay=self.weight_decay,
amsgrad=self.optimizer_name == 'amsgrad')
# Set learning rate scheduler
scheduler = optim.lr_scheduler.MultiStepLR(
optimizer, milestones=self.lr_milestones, gamma=0.1)
# Initialize hypersphere center c (if c not loaded)
if self.c is None:
logger.info('Initializing center c...')
self.c = self.init_center_c(train_loader, net)
logger.info('Center c initialized.')
# Training
logger.info('Starting training...')
start_time = time.time()
net.train()
for epoch in range(self.n_epochs):
scheduler.step()
if epoch in self.lr_milestones:
logger.info(' LR scheduler: new learning rate is %g' %
float(scheduler.get_lr()[0]))
loss_epoch = 0.0
n_batches = 0
epoch_start_time = time.time()
for data in train_loader:
inputs, _, _ = data
inputs = inputs.to(self.device)
# Zero the network parameter gradients
optimizer.zero_grad()
# Update network parameters via backpropagation: forward + backward + optimize
outputs = net(inputs)
dist = torch.sum((outputs - self.c)**2, dim=1)
if self.objective == 'soft-boundary':
scores = dist - self.R**2
loss = self.R**2 + (1 / self.nu) * torch.mean(
torch.max(torch.zeros_like(scores), scores))
else:
loss = torch.mean(dist)
loss.backward()
optimizer.step()
# Update hypersphere radius R on mini-batch distances
if (self.objective == 'soft-boundary') and (
epoch >= self.warm_up_n_epochs):
self.R.data = torch.tensor(get_radius(dist, self.nu),
device=self.device)
loss_epoch += loss.item()
n_batches += 1
# log epoch statistics
epoch_train_time = time.time() - epoch_start_time
logger.info(' Epoch {}/{}\t Time: {:.3f}\t Loss: {:.8f}'.format(
epoch + 1, self.n_epochs, epoch_train_time,
loss_epoch / n_batches))
self.train_time = time.time() - start_time
logger.info('Training time: %.3f' % self.train_time)
logger.info('Finished training.')
return net
