def train_loop(configs: dict, model: GTransformer, opt: torch.optim.Adam,
train: Dataset, test: Dataset,
text_encoder: WhitespaceEncoder) -> GTransformer:
"""
Main training loop.
:param configs: Configs defined on the default.yaml file.
:param model: Sequence-to-sequence transformer.
:param opt: Adam optimizer.
:param train: The dataset used for training.
:param test: The dataset used for validation.
:param text_encoder: Torch NLP text encoder for tokenization and vectorization.
"""
for e in range(configs.get('num_epochs', 8)):
print(f'\n Epoch {e}')
model.train()
nr_batches = math.ceil(len(train) / configs.get('batch_size', 8))
train_iter, test_iter = get_iterators(configs, train, test)
total_loss, steps = 0, 0
for sample in tqdm.tqdm(train_iter, total=nr_batches):
# 0) Zero out previous grads
opt.zero_grad()
# 1) Prepare Sample
src, src_lengths, trg, shifted_trg, trg_lengths = prepare_sample(
sample, text_encoder)
# 2) Run model
lprobs = model(
src=src.cuda(),
trg=shifted_trg.cuda(),
src_mask=lengths_to_mask(src_lengths).unsqueeze(1).cuda(),
trg_mask=lengths_to_mask(trg_lengths).unsqueeze(1).cuda())
# 3) Compute loss
loss = F.nll_loss(lprobs.transpose(2, 1),
trg.cuda(),
reduction='mean')
loss.backward()
# 4) Update training metrics
total_loss += float(loss.item())
steps += int(trg.ne(0).sum())
# 5) clip gradients
# - If the total gradient vector has a length > 1, we clip it back down to 1.
if configs.get('gradient_clipping', -1) > 0.0:
nn.utils.clip_grad_norm_(model.parameters(),
configs.get('gradient_clipping'))
# 6) Optim step
opt.step()
print(f'-- total train loss {total_loss:.4}')
total_steps = steps * (e + 1)
print(f'-- train steps {total_steps}')
validate(model, test_iter, text_encoder)
return model
def train(
model: DepressionDetector, optimizer: torch.optim.Adam,
train_dataset: Dataset, batch_size, num_epochs, writer,
reduction_loss, tensorboard_batch=100, _shuffle=True, last_epoch_count=0
):
"""
train a LSTMNetwork object
:param optimizer:
:param last_epoch_count:
:param _shuffle:
:param reduction_loss:
:param tensorboard_batch:
:param writer:
:param batch_size:
:param train_dataset:
:param num_epochs:
:param model:
:return:
"""
loss_fn = torch.nn.MSELoss(reduction=reduction_loss).cuda()
train_data_loader = DataLoader(train_dataset, batch_size=batch_size, shuffle=_shuffle)
model.train()
running_loss_epoch = 0.0
running_loss_batches = 0.0
last_epoch = last_epoch_count + 1 if last_epoch_count != 0 else last_epoch_count
for epoch in range(0, num_epochs):
try:
for batch, data in enumerate(train_data_loader, 0):
inputs, labels = data
if inputs.shape[0] == batch_size:
inputs, labels = inputs.cuda(), labels.cuda()
out = model(inputs)
loss = loss_fn(out.float(), labels.float())
optimizer.zero_grad()
loss.backward()
optimizer.step()
running_loss_batches += loss.item()
running_loss_epoch += loss.item()
print(f'Epoch {epoch + 1} batch {batch + 1} train loss: {loss.item()}')
if batch % tensorboard_batch == tensorboard_batch - 1:
writer.add_scalar(f'training loss per {tensorboard_batch} batches',
running_loss_batches / tensorboard_batch,
last_epoch * len(train_data_loader) + batch)
running_loss_batches = 0.0
writer.add_scalar('training loss per epoch', running_loss_epoch, last_epoch)
running_loss_epoch = 0.0
last_epoch += 1
except KeyboardInterrupt:
return model, optimizer, last_epoch
return model, optimizer, last_epoch
def train_loop(configs: dict, model: CTransformer, opt: torch.optim.Adam,
train: Dataset, test: Dataset, text_encoder: WhitespaceEncoder,
label_encoder: LabelEncoder) -> CTransformer:
"""
Main training loop.
:param configs: Configs defined on the default.yaml file.
:param model: Transformer Classifier.
:param opt: Adam optimizer.
:param train: The dataset used for training.
:param test: The dataset used for validation.
:param text_encoder: Torch NLP text encoder for tokenization and vectorization.
:param label_encoder: Torch NLP label encoder for vectorization of the labels.
"""
seen = 0
for e in range(configs.get('num_epochs', 8)):
print(f'\n Epoch {e}')
model.train()
nr_batches = math.ceil(len(train) / configs.get('batch_size', 8))
train_iter, test_iter = get_iterators(configs, train, test)
for sample in tqdm.tqdm(train_iter, total=nr_batches):
# 0) Zero out previous grads
opt.zero_grad()
# 1) Prepare Sample
input_seqs, input_mask, targets = prepare_sample(
sample, text_encoder, label_encoder,
configs.get('max_length', 256))
# 2) Run model
out = model(input_seqs.cuda(), input_mask.cuda())
# 3) Compute loss
loss = F.nll_loss(out, targets.cuda())
loss.backward()
# 4) clip gradients
# - If the total gradient vector has a length > 1, we clip it back down to 1.
if configs.get('gradient_clipping', -1) > 0.0:
nn.utils.clip_grad_norm_(model.parameters(),
configs.get('gradient_clipping'))
# 5) Optim step
opt.step()
# 6) Update number of seen examples...
seen += input_seqs.size(0)
validate(model, text_encoder, label_encoder,
configs.get('max_length', 256), test_iter)
return model
def train(model: Model, optimizer: torch.optim.Adam, epoch_num, train_loader,
test_loader, save_dir_best, save_dir_final, device: torch.device):
train_losses = []
best_test_auc = 0.0
for epoch in tqdm(range(epoch_num)):
model.train()
for _, (hist_seq, hist_answers, new_seq, target_answers,
_) in tqdm(enumerate(train_loader)):
hist_seq, hist_answers, new_seq, target_answers = \
hist_seq.to(device), hist_answers.to(device), new_seq.to(device), target_answers.to(device)
# * foward pass
# (batch_size, seq_len - 1, 1)
pred = model(hist_seq, hist_answers, new_seq)
# * compute loss
loss = model.loss(pred, target_answers.float())
train_losses.append(loss.item())
# * backward pass & update
optimizer.zero_grad()
loss.backward()
optimizer.step()
epoch_loss = np.sum(train_losses) / len(train_losses)
model.eval()
test_auc = evaluate(model, test_loader, device)
print("epoch {}: train_loss: {}, test_auc: {}".format(
epoch + 1, epoch_loss, test_auc))
wandb.log({"train_loss": epoch_loss, "test_auc": test_auc})
if test_auc > best_test_auc:
best_test_auc = test_auc
torch.save(model.state_dict(), save_dir_best)
print("best_auc: {} at epoch {}".format(best_test_auc, epoch + 1))
wandb.log({"best_auc": best_test_auc})
print("best_auc: {}".format(best_test_auc))
torch.save(model.state_dict(), save_dir_final)
print("done.")
def train(net: Network, optimizer: torch.optim.Adam,
train_loader: torch.utils.data.DataLoader, epoch: int):
net.train()
for batch_idx, (x, y) in enumerate(train_loader):
optimizer.zero_grad()
output = net(x.view(-1, 28 * 28).to(net.device))
loss = F.nll_loss(output, y.to(net.device))
loss.backward()
optimizer.step()
if batch_idx % 100 == 0:
print(
f"Train Epoch: {epoch}, Step: {batch_idx*len(x)}/{len(train_loader.dataset)}, Loss: {loss.item()}"
)
def train_psnr(train_dataloader: torch.utils.data.DataLoader,
generator: nn.Module, pixel_criterion: nn.MSELoss,
psnr_optimizer: torch.optim.Adam, epoch: int,
writer: SummaryWriter,
args: argparse.ArgumentParser.parse_args):
batch_time = AverageMeter("Time", ":6.4f")
mse_losses = AverageMeter("MSE Loss", ":.6f")
progress = ProgressMeter(len(train_dataloader), [batch_time, mse_losses],
prefix=f"Epoch: [{epoch}]")
# switch to train mode
generator.train()
end = time.time()
for i, (lr, hr) in enumerate(train_dataloader):
# Move data to special device.
if args.gpu is not None:
lr = lr.cuda(args.gpu, non_blocking=True)
hr = hr.cuda(args.gpu, non_blocking=True)
generator.zero_grad()
# Generating fake high resolution images from real low resolution images.
sr = generator(lr)
# The MSE Loss of the generated fake high-resolution image and real high-resolution image is calculated.
mse_loss = pixel_criterion(sr, hr)
mse_loss.backward()
psnr_optimizer.step()
# measure elapsed time
batch_time.update(time.time() - end)
end = time.time()
# measure accuracy and record loss
mse_losses.update(mse_loss.item(), lr.size(0))
iters = i + epoch * len(train_dataloader) + 1
writer.add_scalar("Train/MSE Loss", mse_loss.item(), iters)
# Output results every 100 batches.
if i % 100 == 0:
progress.display(i)
# Save image every 1000 batches.
if iters % 1000 == 0:
vutils.save_image(hr,
os.path.join("runs", "hr", f"PSNR_{iters}.bmp"))
sr = generator(lr)
vutils.save_image(sr.detach(),
os.path.join("runs", "sr", f"PSNR_{iters}.bmp"))
def _train_step(
batch_x: torch.Tensor,
batch_y: torch.Tensor,
cavity_model_net: CavityModel,
optimizer: torch.optim.Adam,
loss_function: torch.nn.CrossEntropyLoss,
) -> (torch.Tensor, float):
"""
Helper function to take a training step
"""
cavity_model_net.train()
optimizer.zero_grad()
batch_y_pred = cavity_model_net(batch_x)
loss_batch = loss_function(batch_y_pred, torch.argmax(batch_y, dim=-1))
loss_batch.backward()
optimizer.step()
return (batch_y_pred, loss_batch.detach().cpu().item())
def train_segments(self, model, l_loss, m_loss,
optimizer: torch.optim.Adam, train_set):
model.train(mode=True)
accuracy_classification_sum = 0
loss_m_sum = 0
loss_l1_sum = 0
loss_classification_sum = 0
batch_count = 0
for images, segments, labels in train_set:
labels, segments = model_utils.reduce_to_class_number(
self.left_class_number, self.right_class_number, labels,
segments)
images, labels, segments = self.convert_data_and_label(
images, labels, segments)
segments = self.puller(segments)
optimizer.zero_grad()
model_classification, model_segmentation = model_utils.wait_while_can_execute(
model, images)
classification_loss = l_loss(model_classification, labels)
segmentation_loss = m_loss(model_segmentation, segments)
#torch.cuda.empty_cache()
segmentation_loss.backward()
optimizer.step()
output_probability, output_cl, cl_acc = self.calculate_accuracy(
labels, model_classification, labels.size(0))
self.save_train_data(labels, output_cl, output_probability)
# accumulate information
accuracy_classification_sum += model_utils.scalar(cl_acc.sum())
loss_m_sum += model_utils.scalar(segmentation_loss.sum())
loss_l1_sum += 0
loss_classification_sum += model_utils.scalar(
classification_loss.sum())
batch_count += 1
#self.de_convert_data_and_label(images, labels, segments)
#torch.cuda.empty_cache()
model.train(mode=False)
return accuracy_classification_sum / (
batch_count +
p.EPS), loss_m_sum / (batch_count + p.EPS), loss_l1_sum / (
batch_count + p.EPS), loss_classification_sum / (batch_count +
p.EPS)
def _train_step(batch: torch.Tensor, pointpillars: torch.nn.Module,
loss_func: torch.nn.Module, optimizer: torch.optim.Adam,
epoch: int, i: int) -> torch.nn.Module:
"""
Performs a training step
"""
pil_batch, ind_batch, label_batch, label_mask = batch
# -> forward pass through network
preds = pointpillars(pil_batch, ind_batch, label_batch, label_mask)
loss = loss_func(preds, writer, epoch, i)
loss.backward()
optimizer.step()
del pil_batch, ind_batch, label_batch, preds
return loss
def train_epoch(model: nn.Module, train_loader: DataLoader,
criterion: nn.CrossEntropyLoss, optimizer: torch.optim.Adam,
device: torch.device, ration):
epoch_loss = 0.0
model.train()
for data in train_loader:
optimizer.zero_grad()
prediction, target = model(data, device=device, ration=ration)
loss = criterion(prediction, target)
loss.backward()
optimizer.step()
epoch_loss += loss.item()
return epoch_loss / len(train_loader.dataset)
def train_step_from_batch(
ts_chunks: torch.Tensor,
targets: torch.Tensor,
distr_tcn: DistributionalTCN,
optimizer: torch.optim.Adam,
):
"""
Arguments
----------
ts_chunks: Mini-batch chunked from the time series
targets: Corresponding chunk of target values
distr_tcn: DistributionalTCN
otimizer: Optimizer containing parameters, learning rate, etc
"""
distr_outputs = distr_tcn(ts_chunks.float())
loss = -distr_outputs.log_prob(targets.float())
loss = loss.mean()
loss_value = loss.cpu().detach().numpy()
loss.backward()
optimizer.step()
return loss_value
def train_loop(num_of_epoch: int, input_data: torch.autograd.Variable, ground_truth: torch.autograd.Variable,
optimizer: torch.optim.Adam, model: torch.nn.Sequential):
"""A simple train loop.
Args:
num_of_epoch (int): Number of epoch.
input_data (torch.autograd.Variable): Input data.
ground_truth(torch.autograd.Variable): Ground truth.
optimizer (torch.optim.Adam): ADAM optimizer
model(torch.nn.Sequential): Neural network model.
"""
loss_fn = torch.nn.MSELoss(reduction='sum')
for t in range(num_of_epoch):
output_pred = model(input_data)
loss = loss_fn(output_pred, ground_truth)
optimizer.zero_grad()
loss.backward()
optimizer.step()
def train_gan(train_dataloader: torch.utils.data.DataLoader,
discriminator: nn.Module, generator: nn.Module,
content_criterion: VGGLoss, adversarial_criterion: nn.BCELoss,
discriminator_optimizer: torch.optim.Adam,
generator_optimizer: torch.optim.Adam, epoch: int,
writer: SummaryWriter, args: argparse.ArgumentParser.parse_args):
batch_time = AverageMeter("Time", ":.4f")
d_losses = AverageMeter("D Loss", ":.6f")
g_losses = AverageMeter("G Loss", ":.6f")
content_losses = AverageMeter("Content Loss", ":.4f")
adversarial_losses = AverageMeter("Adversarial Loss", ":.4f")
d_hr_values = AverageMeter("D(x)", ":.4f")
d_sr1_values = AverageMeter("D(SR1)", ":.4f")
d_sr2_values = AverageMeter("D(SR2)", ":.4f")
progress = ProgressMeter(len(train_dataloader), [
batch_time, d_losses, g_losses, content_losses, adversarial_losses,
d_hr_values, d_sr1_values, d_sr2_values
],
prefix=f"Epoch: [{epoch}]")
# switch to train mode
discriminator.train()
generator.train()
end = time.time()
for i, (lr, hr) in enumerate(train_dataloader):
# Move data to special device.
if args.gpu is not None:
lr = lr.cuda(args.gpu, non_blocking=True)
hr = hr.cuda(args.gpu, non_blocking=True)
batch_size = lr.size(0)
# The real sample label is 1, and the generated sample label is 0.
real_label = torch.full((batch_size, 1), 1,
dtype=lr.dtype).cuda(args.gpu,
non_blocking=True)
fake_label = torch.full((batch_size, 1), 0,
dtype=lr.dtype).cuda(args.gpu,
non_blocking=True)
##############################################
# (1) Update D network: maximize - E(hr)[log(D(hr))] + E(lr)[log(1- D(G(lr))]
##############################################
# Set discriminator gradients to zero.
discriminator.zero_grad()
real_output = discriminator(hr)
# Let the discriminator realize that the sample is real.
d_loss_real = adversarial_criterion(real_output, real_label)
# Generating fake high resolution images from real low resolution images.
sr = generator(lr)
fake_output = discriminator(sr.detach())
# Let the discriminator realize that the sample is false.
d_loss_fake = adversarial_criterion(fake_output, fake_label)
# Count all discriminator losses.
d_loss = (d_loss_real + d_loss_fake) / 2
d_loss.backward()
d_hr = real_output.mean().item()
d_sr1 = fake_output.mean().item()
# Update discriminator optimizer gradient information.
discriminator_optimizer.step()
##############################################
# (2) Update G network: content loss + 0.001 * adversarial loss
##############################################
# Set discriminator gradients to zero.
generator.zero_grad()
# Based on VGG19_36th pre training model to find the maximum square error between feature maps.
content_loss = content_criterion(sr, hr.detach())
fake_output = discriminator(sr)
# Let the discriminator realize that the sample is true.
adversarial_loss = adversarial_criterion(fake_output, real_label)
g_loss = content_loss + 0.001 * adversarial_loss
g_loss.backward()
d_sr2 = fake_output.mean().item()
# Update generator optimizer gradient information.
generator_optimizer.step()
# measure accuracy and record loss
d_losses.update(d_loss.item(), lr.size(0))
g_losses.update(g_loss.item(), lr.size(0))
content_losses.update(content_loss.item(), lr.size(0))
adversarial_losses.update(adversarial_loss.item(), lr.size(0))
d_hr_values.update(d_hr, lr.size(0))
d_sr1_values.update(d_sr1, lr.size(0))
d_sr2_values.update(d_sr2, lr.size(0))
# measure elapsed time
batch_time.update(time.time() - end)
end = time.time()
iters = i + epoch * len(train_dataloader) + 1
writer.add_scalar("Train/D Loss", d_loss.item(), iters)
writer.add_scalar("Train/G Loss", g_loss.item(), iters)
writer.add_scalar("Train/Content Loss", content_loss.item(), iters)
writer.add_scalar("Train/Adversarial Loss", adversarial_loss.item(),
iters)
writer.add_scalar("Train/D(LR)", d_hr, iters)
writer.add_scalar("Train/D(SR1)", d_sr1, iters)
writer.add_scalar("Train/D(SR2)", d_sr2, iters)
# Output results every 100 batches.
if i % 100 == 0:
progress.display(i)
# Save image every 1000 batches.
if iters % 1000 == 0:
vutils.save_image(hr, os.path.join("runs", "hr",
f"GAN_{iters}.bmp"))
sr = generator(lr)
vutils.save_image(sr.detach(),
os.path.join("runs", "sr", f"GAN_{iters}.bmp"))
def fit(self,
train_dataloader: DataLoader,
train_len: int,
epochs: int,
criterion: nn.CrossEntropyLoss,
optimizer: torch.optim.Adam,
verbose=True,
device="cuda",
test_dataloader=None,
test_len=None,
use_nni=False,
save_checkpoints=False,
model_save_threshold=0.85) -> dict:
self.train()
results = dict()
results["train_acc"] = list()
results["train_loss"] = list()
results["train_precision"] = list()
results["train_recall"] = list()
results["train_f1"] = list()
if test_dataloader is not None:
results["test_acc"] = list()
results["test_loss"] = list()
results["test_precision"] = list()
results["test_recall"] = list()
results["test_f1"] = list()
self.to(device)
if verbose:
print("statring training...")
for epoch in tqdm.tqdm(
range(epochs)): # loop over the dataset multiple times
running_loss = 0.0
for i, data in enumerate(
tqdm.tqdm(train_dataloader)): # mini-batch
self.train()
inputs, mask, target_mask, labels = data
outputs = self(inputs, mask, target_mask)
loss = criterion(outputs, labels)
loss.backward()
optimizer.step()
optimizer.zero_grad()
# print statistics
#running_loss += loss.item()
y_real, y_pred = calc_performance(self, train_dataloader)
acc, precision, recall, f1 = calc_classification_metrics(
y_true=y_real, y_pred=y_pred)
if verbose:
print(
f'\tEp #{epoch} | Train. Loss: {loss:.3f} | Acc: {acc * 100:.2f}% | Precision: {precision * 100:.2f}% | Recall: {recall * 100:.2f}% | F1: {f1 * 100:.2f}%'
)
results["train_acc"].append(acc)
results["train_loss"].append(loss)
results["train_precision"].append(precision)
results["train_recall"].append(recall)
results["train_f1"].append(f1)
if test_dataloader is not None:
y_real, y_pred = calc_performance(self, test_dataloader)
test_acc, precision, recall, test_f1 = calc_classification_metrics(
y_true=y_real, y_pred=y_pred)
if verbose:
print(
f'\tEp #{epoch} | Dev. '
f'cc: {acc * 100:.2f}% | Precision: {precision * 100:.2f}% | Recall: {recall * 100:.2f}% | F1: {f1 * 100:.2f}%'
)
results["test_acc"].append(acc)
results["test_loss"].append(loss)
results["test_precision"].append(precision)
results["test_recall"].append(recall)
results["test_f1"].append(f1)
if save_checkpoints and model_save_threshold <= acc:
model_name = self.generate_model_save_name(acc)
model_path = os.path.join("models", model_name)
torch.save(self, model_path)
if use_nni:
nni.report_intermediate_result({
"train_acc": acc,
"train_f1": f1,
"default": test_acc,
"test_f1": test_f1
})
if verbose:
print('Finished Training')
return results
def train(
#train_config: TrainingConfiguration, model: nn.Module, optimizer: torch.optim.Optimizer,
train_config: TrainingConfiguration, model: nn.Module, optimizer: torch.optim.Adam,
train_loader: torch.utils.data.DataLoader, epoch_idx: int
) -> None:
# change model in training mood
model.train()
# to get batch loss
batch_loss = np.array([])
# to get batch accuracy
batch_acc = np.array([])
for batch_idx, (data, target) in enumerate(train_loader):
# clone target
indx_target = target.clone()
# send data to device (its is medatory if GPU has to be used)
data = data.to(train_config.device)
# send target to device
target = target.to(train_config.device)
# reset parameters gradient to zero
optimizer.zero_grad()
# forward pass to the model
output = model(data)
# cross entropy loss
loss = F.cross_entropy(output, target)
# find gradients w.r.t training parameters
loss.backward()
# Update parameters using gardients
optimizer.step()
batch_loss = np.append(batch_loss, [loss.item()])
# Score to probability using softmax
prob = F.softmax(output, dim=1)
# get the index of the max probability
pred = prob.data.max(dim=1)[1]
# correct prediction
correct = pred.cpu().eq(indx_target).sum()
# accuracy
acc = float(correct) / float(len(data))
batch_acc = np.append(batch_acc, [acc])
if batch_idx % train_config.log_interval == 0 and batch_idx > 0:
print(
'Train Epoch: {} [{}/{}] Loss: {:.6f} Acc: {:.4f}'.format(
epoch_idx, batch_idx * len(data), len(train_loader.dataset), loss.item(), acc
)
)
epoch_loss = batch_loss.mean()
epoch_acc = batch_acc.mean()
return epoch_loss, epoch_acc
def eval_on_series(
distr_tcn: DistributionalTCN,
optimizer: torch.optim.Adam,
series_tensor: torch.Tensor,
ts_len: int,
context_length: int,
is_train: bool = False,
return_predictions: bool = False,
lead_time: int = 1,
):
"""
Arguments
----------
distr_tcn: DistributionalTCN
otimizer: Optimizer containing parameters, learning rate, etc
series_tensor: Time series
ts_len: Length of time series
context_length: Number of time steps to input
is_train: True if time series is training set
return_predictions: True if to return (loss, predictions), False if to return loss only
lead_time: Number of time steps to predict ahead
"""
loss_log = []
### Parallelising the training:
trying_mini_batches = True
if is_train:
mini_batch_size = 64
stride = 1
window_length = context_length + lead_time
unfold_layer = torch.nn.Unfold(
kernel_size=(1, window_length), stride=stride
)
fold_layer = torch.nn.Fold(
kernel_size=(1, window_length),
stride=stride,
output_size=(1, series_tensor.shape[-1]),
)
ts_windows = (
unfold_layer(series_tensor.unsqueeze(2))
.transpose(1, 2)
.transpose(0, 1)
)
numb_mini_batches = ts_windows.shape[0] // mini_batch_size
if trying_mini_batches:
batch_indices = np.arange(ts_len - window_length - 1)
# for i in tqdm(range(numb_mini_batches), position=0, leave=True):
for i in range(numb_mini_batches):
idx = np.random.choice(batch_indices, mini_batch_size)
batch_indices = np.setdiff1d(batch_indices, idx)
ts_chunks = ts_windows[idx, :, :-lead_time]
targets = ts_windows[idx, :, -1]
loss_log.append(
train_step_from_batch(
ts_chunks, targets, distr_tcn, optimizer
)
)
else:
ts_chunks = ts_windows[:, :, :-lead_time]
targets = ts_windows[:, :, -1]
loss_log.append(train_step_from_batch(ts_chunks, targets))
return loss_log
if return_predictions:
predictions = {
"low_lower": [],
"lower": [],
"median": [],
"upper": [],
"up_upper": [],
}
for i in range(ts_len - context_length - lead_time - 1):
ts_chunk = series_tensor[:, :, i : i + context_length]
target = series_tensor[:, :, i + context_length + lead_time - 1]
distr_output = distr_tcn(ts_chunk.float())
if return_predictions:
predictions["lower"].append(distr_output.icdf(torch.tensor(0.05)))
predictions["median"].append(distr_output.icdf(torch.tensor(0.5)))
predictions["upper"].append(distr_output.icdf(torch.tensor(0.95)))
predictions["low_lower"].append(
distr_output.icdf(torch.tensor(0.01))
)
predictions["up_upper"].append(
distr_output.icdf(torch.tensor(0.99))
)
loss = -distr_output.log_prob(target.float())
loss_value = loss.cpu().detach().numpy()[0]
loss_log.append(loss_value)
if is_train:
loss.backward()
optimizer.step()
if return_predictions:
return loss_log, predictions
return loss_log
def train_gan(dataloader: torch.utils.data.DataLoader,
discriminator: nn.Module,
discriminator_optimizer: torch.optim.Adam,
generator: nn.Module,
generator_optimizer: torch.optim.Adam,
content_criterion: VGGLoss,
adversarial_criterion: nn.BCELoss,
epoch: int,
writer: SummaryWriter,
args: argparse.ArgumentParser.parse_args):
batch_time = AverageMeter("Time", ":.4f")
d_losses = AverageMeter("D Loss", ":.6f")
g_losses = AverageMeter("G Loss", ":.6f")
content_losses = AverageMeter("Content Loss", ":.4f")
adversarial_losses = AverageMeter("Adversarial Loss", ":.4f")
progress = ProgressMeter(num_batches=len(dataloader),
meters=[batch_time, d_losses, g_losses, content_losses, adversarial_losses],
prefix=f"Epoch: [{epoch}]")
# switch to train mode
discriminator.train()
generator.train()
end = time.time()
for i, (lr, hr) in enumerate(dataloader):
# Move data to special device.
if args.gpu is not None:
lr = lr.cuda(args.gpu, non_blocking=True)
hr = hr.cuda(args.gpu, non_blocking=True)
batch_size = lr.size(0)
# The real sample label is 1, and the generated sample label is 0.
real_label = torch.full((batch_size, 1), 1, dtype=lr.dtype).cuda(args.gpu, non_blocking=True)
fake_label = torch.full((batch_size, 1), 0, dtype=lr.dtype).cuda(args.gpu, non_blocking=True)
##############################################
# (1) Update D network: maximize - E(hr)[log(D(hr))] + E(lr)[log(1- D(G(lr))]
##############################################
discriminator.zero_grad()
# Generating fake high resolution images from real low resolution images.
sr = generator(lr)
# Adversarial loss for real and fake images (origin GAN)
d_loss_real = adversarial_criterion(discriminator(hr), real_label)
d_loss_fake = adversarial_criterion(discriminator(sr.detach()), fake_label)
# Count all discriminator losses.
d_loss = d_loss_real + d_loss_fake
d_loss.backward()
discriminator_optimizer.step()
##############################################
# (2) Update G network: content loss + 0.001 * adversarial loss
##############################################
generator.zero_grad()
# The 36th layer in VGG19 is used as the feature extractor by default
content_loss = content_criterion(sr, hr.detach())
# Adversarial loss for real and fake images (origin GAN).
adversarial_loss = adversarial_criterion(discriminator(sr), real_label)
# Count all generator losses.
g_loss = content_loss + 0.001 * adversarial_loss
g_loss.backward()
generator_optimizer.step()
# measure elapsed time
batch_time.update(time.time() - end)
end = time.time()
# measure accuracy and record loss
d_losses.update(d_loss.item(), lr.size(0))
g_losses.update(g_loss.item(), lr.size(0))
content_losses.update(content_loss.item(), lr.size(0))
adversarial_losses.update(adversarial_loss.item(), lr.size(0))
iters = i + epoch * len(dataloader) + 1
writer.add_scalar("Train/D_Loss", d_loss.item(), iters)
writer.add_scalar("Train/G_Loss", g_loss.item(), iters)
writer.add_scalar("Train/Content_Loss", content_loss.item(), iters)
writer.add_scalar("Train/Adversarial_Loss", adversarial_loss.item(), iters)
# Output results every 100 batches.
if i % 100 == 0:
progress.display(i)
# Each Epoch validates the model once.
sr = generator(base_image)
vutils.save_image(sr.detach(), os.path.join("runs", f"GAN_epoch_{epoch}.png"))
def model_train(model: nn.Module, train_loader: DataLoader,
optimizer: torch.optim.Adam, num_epochs: int,
loss_function: Callable[
[torch.Tensor, torch.Tensor, torch.Tensor, torch.Tensor],
float], device: str) -> List[float]:
'''
Function for training a given input model.
Parameters
----------
model : nn.Model
Model, i.e. varational autoencoder, which needs to be trained.
train_loader : DataLoader
DataLoder of the custom training set used training utilities such as mini-batches and shuffling.
optimizer : torch.optim.Adam
Adam optimizer for the recalculation of the neural network weights by minimizing the calculated loss.
num_epochs : int
Number of training epochs of the model.
loss_function : Callable[[torch.Tensor, torch.Tensor, torch.Tensor, torch.Tensor], float]
Custom loss input function for error calculation.
device : str
Device on which the computation is performed. Typically it is either cpu or cuda (gpu).
Returns
-------
running_rec_loss : list
Returns the list of values relating to the average error at the end of each epoch.
'''
running_rec_loss = []
loss = 0
model.train()
tqdm_bar = tqdm(range(1, num_epochs + 1), desc="epoch [loss: ...]")
for epoch in tqdm_bar:
train_loss_averager = make_averager()
batch_bar = tqdm(train_loader,
leave=False,
desc='batch',
total=len(train_loader))
for batch in batch_bar:
batch = batch.float()
batch = batch.to(device)
batch_reconstructed, latent_mu, latent_logvar = model(batch)
loss = loss_function(batch_reconstructed, batch, latent_mu,
latent_logvar)
#Backpropagation
optimizer.zero_grad()
loss.backward()
optimizer.step()
refresh_bar(
batch_bar,
f"train batch [loss: {train_loss_averager(loss.item()):.3f}]")
refresh_bar(tqdm_bar, f"epoch [loss: {train_loss_averager(None):.3f}]")
running_rec_loss.append(train_loss_averager(None))
return running_rec_loss