示例#1
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	def train_epoch(self, net :BaseNet, train_loader ):
		self.accuracy.zero()
		net.train()
		self.scheduler.step()

		loss_epoch = 0.0
		n_batches = 0
		dist = 0
		epoch_start_time = time.time()
		for data in train_loader:
			inputs, y = data

			# Zero the network parameter gradients
			self.optimizer.zero_grad()

			# Update network parameters via backpropagation: forward + backward + optimize
			outputs = self.predict(inputs, net)
			loss = self.criterion(outputs, y)
			if torch.isnan(loss):
				raise ValueError('loss is nan while training')
			self.accuracy(inputs, outputs, y)
			loss.backward()
			self.optimizer.step()

			loss_epoch += loss.item()
			n_batches += 1

		# log epoch statistics
		epoch_train_time = time.time() - epoch_start_time
		return loss_epoch, self.accuracy.value, epoch_train_time, n_batches
示例#2
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    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
示例#3
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    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
示例#4
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    def fit(self, dataset: BaseDataset, net: BaseNet):
        logger = logging.getLogger()

        # 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)

        # Early stopping

        # Loss criterion
        self.criterion = nn.CrossEntropyLoss()

        # 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
            success_rate = 0
            n_batches = 0
            epoch_start_time = time.time()
            for data in train_loader:
                inputs, y = data

                # Zero the network parameter gradients
                optimizer.zero_grad()

                # Update network parameters via backpropagation: forward + backward + optimize
                outputs = self.predict(inputs, net)
                loss = self.criterion(outputs, y)
                loss.backward()
                optimizer.step()

                loss_epoch += loss.item()
                success_rate += inputs.size(0) - torch.nonzero(
                    torch.max(outputs, dim=1)[1] - y).size(0)
                n_batches += 1

            # log epoch statistics
            epoch_train_time = time.time() - epoch_start_time
            logger.info(
                '  Epoch {}/{}\t Time: {:.3f}\t Loss: {:.8f}\t Success Rate:{:.5f}'
                .format(epoch + 1, self.n_epochs, epoch_train_time,
                        loss_epoch / n_batches,
                        success_rate / train_loader.dataset.len))

        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
示例#6
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    def fit(self, dataset: BaseDataset, net: BaseNet):
        logger = logging.getLogger()

        # 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)

        # Early stopping

        # Loss criterion
        self.criterion = self.weighted_mse
        #self.criterion = nn.MSELoss()
        # 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
            dist = 0
            epoch_start_time = time.time()
            for data in train_loader:
                inputs, y = data

                # Zero the network parameter gradients
                optimizer.zero_grad()

                # Update network parameters via backpropagation: forward + backward + optimize
                outputs = self.predict(inputs, net)
                loss = self.criterion(outputs, y)
                loss.backward()
                optimizer.step()

                loss_epoch += loss.item()
                n_batches += 1

                diff = torch.abs((outputs - y) / (y + 1e-3))
                dist += torch.mean(diff)

            # log epoch statistics
            epoch_train_time = time.time() - epoch_start_time
            logger.info(
                '  Epoch {}/{}\t Time: {:.3f}\t Loss: {:.8f}\t Accuracy: {:.4f}'
                .format(epoch + 1, self.n_epochs, epoch_train_time,
                        loss_epoch / n_batches, 1 - dist.item() / n_batches))
        self.train_time = time.time() - start_time
        logger.info('Training time: %.3f' % self.train_time)

        logger.info('Finished training.')

        return net