示例#1
0
XTrain = Variable(torch.FloatTensor(XTrain))
YTrain = Variable(torch.FloatTensor(YTrain))

XTest = Variable(torch.FloatTensor(XTest))
YTest = Variable(torch.FloatTensor(YTest))

train_set = MyDataset(x=XTrain, y=YTrain)
train_loader = DataLoader(train_set, batch_size=BATCH_SIZE, shuffle=True)

model = MyNet(n_in=1, n_out=1).to(device)

model.eval()
YPRED = model.forward(XTest)

criterion = nn.MSELoss()
optimizer = optim.Adam(model.parameters(), lr=INITIAL_LEARNING_RATE)
scheduler = StepLR(optimizer, 20)

for epoch in range(N_EPOCHS):
    model.train()
    epoch_loss = 0
    for i, (x, y) in enumerate(train_loader):
        x.to(device)
        y.to(device)
        #        set_trace()
        optimizer.zero_grad()
        y_pred = model(x)
        loss = criterion(y_pred, y)
        epoch_loss += loss
        #        plt.figure(1)
        #        plt.plot(i, loss.detach().numpy(), '*')
def main(config, resume):

    # parameters
    batch_size = config.get('batch_size', 32)
    start_epoch = config['epoch']['start']
    max_epoch = config['epoch']['max']
    lr = config.get('lr', 0.0005)
    use_conf = config.get('use_conf', False)

    ## path
    save_path = config['save_path']
    timestamp = datetime.now().strftime(r"%Y-%m-%d_%H-%M-%S")
    save_path = os.path.join(save_path, timestamp)

    result_path = os.path.join(save_path, 'result')
    if not os.path.exists(result_path):
        os.makedirs(result_path)

    model_path = os.path.join(save_path, 'model')
    if not os.path.exists(model_path):
        os.makedirs(model_path)

    dest = shutil.copy('train.py', save_path)
    print("save to: ", dest)

    ## cuda or cpu
    if config['n_gpu'] == 0 or not torch.cuda.is_available():
        device = torch.device("cpu")
        print("using CPU")
    else:
        device = torch.device("cuda:0")

    ## dataloader
    dataset = Dataset(phase='train', do_augmentations=False)
    data_loader = DataLoader(
        dataset,
        batch_size=int(batch_size),
        num_workers=1,
        shuffle=True,
        drop_last=True,
        pin_memory=True,
        # **loader_kwargs,
    )

    val_dataset = Dataset(phase='val', do_augmentations=False)
    val_data_loader = DataLoader(
        val_dataset,
        batch_size=int(batch_size),
        num_workers=1,
        shuffle=True,
        drop_last=True,
        pin_memory=True,
        # **loader_kwargs,
    )

    ## few shot
    do_few_shot = True
    if do_few_shot:
        fs_dataset = Dataset(
            phase='train',
            do_augmentations=False,
            metafile_path='metadata/detection_train_images.json')
        fs_data_loader = DataLoader(
            fs_dataset,
            batch_size=int(128),
            num_workers=1,
            shuffle=True,
            pin_memory=True,
            # **loader_kwargs,
        )

    ## CNN model
    output_dim = 3
    model = MyNet(output_dim)
    model = model.to(device)
    model.train()
    print(model)

    ## loss
    criterion = nn.CrossEntropyLoss(reduction='none')

    ## optimizer
    params = list(filter(lambda p: p.requires_grad, model.parameters()))
    optim_params = {
        'lr': lr,
        'weight_decay': 0,
        'amsgrad': False,
    }
    optimizer = torch.optim.Adam(params, **optim_params)
    lr_params = {
        'milestones': [10],
        'gamma': 0.1,
    }
    lr_scheduler = torch.optim.lr_scheduler.MultiStepLR(optimizer, **lr_params)

    loss_avg = AverageMeter()
    acc_avg = AverageMeter()
    fs_loss_avg = AverageMeter()
    fs_acc_avg = AverageMeter()
    logger = SimpleLogger(['train_loss', 'train_acc', 'val_loss', 'val_acc'])

    ## loop
    for epoch in range(start_epoch, max_epoch):
        loss_avg.reset()

        for batch_idx, batch in tqdm(
                enumerate(data_loader),
                total=len(data_loader),
                ncols=80,
                desc=f'training epoch {epoch}',
        ):
            data = batch[0].to(device)
            gt_lbls = batch[1].to(device)
            gt_gt_lbls = batch[2].to(device)

            ## set zerograd
            optimizer.zero_grad()

            ## run forward pass
            out = model(data)  ## logits: [B, NC]; conf: [B, 1]
            preds = torch.max(out, dim=-1)[1]
            # print("out shape: ", out.shape)

            weights = model.compute_entropy_weight(out)
            # print("weights shape: ", weights.shape)

            ## compute loss
            class_loss = criterion(out, gt_lbls)  ## [B, 1]
            # print("class_loss shape: ", class_loss.shape)

            if use_conf:
                loss = (class_loss * (weights**2) + (1 - weights)**2).mean()
            else:
                loss = class_loss.mean()

            ## record
            loss_avg.update(loss.item(), batch_size)
            positive = ((gt_lbls == preds) + (gt_gt_lbls > 2)).sum()
            batch_acc = positive.to(torch.float) / batch_size
            acc_avg.update(batch_acc.item(), batch_size)

            ## run backward pass
            loss.backward()
            optimizer.step()  ## update

        ## each epoch
        logger.update(loss_avg.avg, 'train_loss')
        logger.update(acc_avg.avg, 'train_acc')
        print("train loss: ", loss_avg.avg)
        print("train acc: ", acc_avg.avg)

        if do_few_shot and fs_data_loader is not None:
            for batch_idx, batch in tqdm(
                    enumerate(fs_data_loader),
                    total=len(fs_data_loader),
                    ncols=80,
                    desc=f'training epoch {epoch}',
            ):
                data = batch[0].to(device)
                gt_lbls = batch[1].to(device)
                gt_gt_lbls = batch[2].to(device)

                ## set zerograd
                optimizer.zero_grad()

                ## run forward pass
                out = model(data)  ## logits: [B, NC]; conf: [B, 1]
                preds = torch.max(out, dim=-1)[1]
                # print("out shape: ", out.shape)

                weights = model.compute_entropy_weight(out)
                # print("weights shape: ", weights.shape)

                ## compute loss
                class_loss = criterion(out, gt_lbls)  ## [B, 1]
                # print("class_loss shape: ", class_loss.shape)

                if use_conf:
                    loss = (class_loss * (weights**2) +
                            (1 - weights)**2).mean()
                else:
                    loss = class_loss.mean()

                ## record
                positive = ((gt_lbls == preds) + (gt_gt_lbls > 2)).sum()
                batch_acc = positive.to(torch.float) / data.shape[0]
                fs_loss_avg.update(loss.item(), data.shape[0])
                fs_acc_avg.update(batch_acc.item(), data.shape[0])

                ## run backward pass
                loss = loss * 1.0
                loss.backward()
                optimizer.step()  ## update

            # print(f"\nfew-shot: {preds}, {gt_gt_lbls}")
            ## each epoch
            print("fs train loss: ", fs_loss_avg.avg)
            print("fs train acc: ", fs_acc_avg.avg)

        if val_data_loader is not None:
            log = evaluate(model.eval(),
                           val_data_loader,
                           device,
                           use_conf=use_conf)
            model.train()

            logger.update(log['loss'], 'val_loss')
            logger.update(log['acc'], 'val_acc')
            print("val loss: ", log['loss'])
            print("val acc: ", log['acc'])

        best_idx = logger.get_best('val_acc', best='max')
        if best_idx == epoch:
            print('save ckpt')
            ## save ckpt
            _save_checkpoint(model_path, epoch, model)

        lr_scheduler.step()
        print()

    ## save final model
    _save_checkpoint(model_path, epoch, model)
示例#3
0
                                          shuffle=False,
                                          num_workers=4)

text_labels = [
    't-shirt', 'trouser', 'pullover', 'dress', 'coat', 'sandal', 'shirt',
    'sneaker', 'bag', 'ankle boot'
]
#vis_datasets(train_loader,text_labels)

epoch_size = 20
lr = 0.001
device = torch.device('cuda')

net = MyNet(1).to(device)

optimizer = optim.Adam(net.parameters(), lr=lr)
scheduler = optim.lr_scheduler.MultiStepLR(optimizer,
                                           milestones=[14, 19],
                                           gamma=0.1,
                                           last_epoch=-1)
criterion = nn.CrossEntropyLoss()
loss_total = 0

for epoch in range(epoch_size):

    for index, (imgs, labels) in enumerate(train_loader):
        imgs, labels = imgs.to(device), labels.to(device)
        optimizer.zero_grad()
        out = net(imgs)
        loss = criterion(out, labels)
        loss.backward()