def train_ch6(net, train_iter, test_iter, num_epochs, lr,
device=d2l.try_gpu()):
"""Train a model with a GPU (defined in Chapter 6)."""
net.initialize(force_reinit=True, ctx=device, init=init.Xavier())
loss = gluon.loss.SoftmaxCrossEntropyLoss()
trainer = gluon.Trainer(net.collect_params(),
'sgd', {'learning_rate': lr})
animator = d2l.Animator(xlabel='epoch', xlim=[1, num_epochs],
legend=['train loss', 'train acc', 'test acc'])
timer, num_batches = d2l.Timer(), len(train_iter)
for epoch in range(num_epochs):
# Sum of training loss, sum of training accuracy, no. of examples
metric = d2l.Accumulator(3)
for i, (X, y) in enumerate(train_iter):
timer.start()
# Here is the major difference from `d2l.train_epoch_ch3`
X, y = X.as_in_ctx(device), y.as_in_ctx(device)
with autograd.record():
y_hat = net(X)
l = loss(y_hat, y)
l.backward()
trainer.step(X.shape[0])
metric.add(l.sum(), d2l.accuracy(y_hat, y), X.shape[0])
timer.stop()
train_l = metric[0] / metric[2]
train_acc = metric[1] / metric[2]
if (i + 1) % (num_batches // 5) == 0 or i == num_batches - 1:
animator.add(epoch + (i + 1) / num_batches,
(train_l, train_acc, None))
test_acc = evaluate_accuracy_gpu(net, test_iter)
animator.add(epoch + 1, (None, None, test_acc))
print(f'loss {train_l:.3f}, train acc {train_acc:.3f}, '
f'test acc {test_acc:.3f}')
print(f'{metric[2] * num_epochs / timer.sum():.1f} examples/sec '
f'on {str(device)}')
def train_recsys_rating(net, train_iter, test_iter, loss, trainer, num_epochs,
devices=d2l.try_all_gpus(), evaluator=None,
**kwargs):
timer = d2l.Timer()
animator = d2l.Animator(xlabel='epoch', xlim=[1, num_epochs], ylim=[0, 2],
legend=['train loss', 'test RMSE'])
for epoch in tqdm.tqdm(range(num_epochs)):
metric, l = d2l.Accumulator(3), 0.
for i, values in enumerate(train_iter):
timer.start()
input_data = []
values = values if isinstance(values, list) else [values]
for v in values:
input_data.append(gluon.utils.split_and_load(v, devices))
train_feat = input_data[0:-1] if len(values) > 1 else input_data
train_label = input_data[-1]
with autograd.record():
preds = [net(*t) for t in zip(*train_feat)]
ls = [loss(p, s) for p, s in zip(preds, train_label)]
[l.backward() for l in ls]
l += sum([l.asnumpy() for l in ls]).mean() / len(devices)
trainer.step(values[0].shape[0])
metric.add(l, values[0].shape[0], values[0].size)
timer.stop()
if len(kwargs) > 0: # It will be used in section AutoRec
test_rmse = evaluator(net, test_iter, kwargs['inter_mat'],
devices)
else:
test_rmse = evaluator(net, test_iter, devices)
train_l = l / (i + 1)
animator.add(epoch + 1, (train_l, test_rmse))
print(f'train loss {metric[0] / metric[1]:.3f}, '
f'test RMSE {test_rmse:.3f}')
print(f'{metric[2] * num_epochs / timer.sum():.1f} examples/sec '
f'on {str(devices)}')
def train(train_features,
test_features,
train_labels,
test_labels,
num_epochs=400):
loss = gluon.loss.L2Loss()
net = nn.Sequential()
# Switch off the bias since we already catered for it in the polynomial
# features
net.add(nn.Dense(1, use_bias=False))
net.initialize()
batch_size = min(10, train_labels.shape[0])
train_iter = d2l.load_array((train_features, train_labels), batch_size)
test_iter = d2l.load_array((test_features, test_labels),
batch_size,
is_train=False)
trainer = gluon.Trainer(net.collect_params(), 'sgd',
{'learning_rate': 0.01})
animator = d2l.Animator(xlabel='epoch',
ylabel='loss',
yscale='log',
xlim=[1, num_epochs],
ylim=[1e-3, 1e2],
legend=['train', 'test'])
for epoch in range(num_epochs):
d2l.train_epoch_ch3(net, train_iter, loss, trainer)
if epoch == 0 or (epoch + 1) % 20 == 0:
animator.add(epoch + 1, (evaluate_loss(
net, train_iter, loss), evaluate_loss(net, test_iter, loss)))
print('weight:', net[0].weight.data().asnumpy())
def train(net, train_iter, valid_iter, num_epochs, lr, wd, devices, lr_period,
lr_decay):
trainer = gluon.Trainer(net.collect_params(), 'sgd',
{'learning_rate': lr, 'momentum': 0.9, 'wd': wd})
num_batches, timer = len(train_iter), d2l.Timer()
animator = d2l.Animator(xlabel='epoch', xlim=[1, num_epochs],
legend=['train loss', 'train acc', 'valid acc'])
for epoch in range(num_epochs):
metric = d2l.Accumulator(3)
if epoch > 0 and epoch % lr_period == 0:
trainer.set_learning_rate(trainer.learning_rate * lr_decay)
for i, (features, labels) in enumerate(train_iter):
timer.start()
l, acc = d2l.train_batch_ch13(
net, features, labels.astype('float32'), loss, trainer,
devices, d2l.split_batch)
metric.add(l, acc, labels.shape[0])
timer.stop()
if (i + 1) % (num_batches // 5) == 0 or i == num_batches - 1:
animator.add(epoch + (i + 1) / num_batches,
(metric[0] / metric[2], metric[1] / metric[2],
None))
if valid_iter is not None:
valid_acc = d2l.evaluate_accuracy_gpus(net, valid_iter,
d2l.split_batch)
animator.add(epoch + 1, (None, None, valid_acc))
if valid_iter is not None:
print(f'loss {metric[0] / metric[2]:.3f}, '
f'train acc {metric[1] / metric[2]:.3f}, '
f'valid acc {valid_acc:.3f}')
else:
print(f'loss {metric[0] / metric[2]:.3f}, '
f'train acc {metric[1] / metric[2]:.3f}')
print(f'{metric[2] * num_epochs / timer.sum():.1f} examples/sec '
f'on {str(devices)}')
def train_ranking(net,
train_iter,
test_iter,
loss,
trainer,
test_seq_iter,
num_users,
num_items,
num_epochs,
devices,
evaluator,
candidates,
eval_step=1):
timer, hit_rate, auc = d2l.Timer(), 0, 0
animator = d2l.Animator(xlabel='epoch',
xlim=[1, num_epochs],
ylim=[0, 1],
legend=['test hit rate', 'test AUC'])
for epoch in range(num_epochs):
metric, l = d2l.Accumulator(3), 0.
for i, values in enumerate(train_iter):
# values: (batch_size, user_id, observered_item_id, unobserverd_item_id)
input_data = []
for v in values:
# values: (user_id, observered_item_id, unobserverd_item_id)
input_data.append(gluon.utils.split_and_load(v, devices))
with autograd.record():
p_pos = [net(*t) for t in zip(*input_data[0:-1])]
p_neg = [
net(*t) for t in zip(*input_data[0:-2], input_data[-1])
]
ls = [loss(p, n) for p, n in zip(p_pos, p_neg)]
[l.backward(retain_graph=False) for l in ls]
l += sum([l.asnumpy() for l in ls]).mean() / len(devices)
trainer.step(values[0].shape[0])
metric.add(l, values[0].shape[0], values[0].size)
timer.stop()
with autograd.predict_mode():
if (epoch + 1) % eval_step == 0:
hit_rate, auc = evaluator(net, test_iter, test_seq_iter,
candidates, num_users, num_items,
devices)
animator.add(epoch + 1, (hit_rate, auc))
print(f'train loss {metric[0] / metric[1]:.3f}, '
f'test hit rate {float(hit_rate):.3f}, test AUC {float(auc):.3f}')
print(f'{metric[2] * num_epochs / timer.sum():.1f} examples/sec '
f'on {str(devices)}')
def train_bert(train_iter, net, loss, vocab_size, ctx, log_interval,
num_steps):
trainer = gluon.Trainer(net.collect_params(), 'adam',
{'learning_rate': 1e-3})
step, timer = 0, d2l.Timer()
animator = d2l.Animator(xlabel='step',
ylabel='loss',
xlim=[1, num_steps],
legend=['mlm', 'nsp'])
# Sum of masked language modeling losses, sum of next sentence prediction
# losses, no. of sentence pairs, count
metric = d2l.Accumulator(4)
num_steps_reached = False
while step < num_steps and not num_steps_reached:
for batch in train_iter:
(tokens_X_shards, segments_X_shards, valid_lens_x_shards,
pred_positions_X_shards, mlm_weights_X_shards, mlm_Y_shards,
nsp_y_shards) = [
gluon.utils.split_and_load(elem, ctx, even_split=False)
for elem in batch
]
timer.start()
with autograd.record():
mlm_ls, nsp_ls, ls = _get_batch_loss_bert(
net, loss, vocab_size, tokens_X_shards, segments_X_shards,
valid_lens_x_shards, pred_positions_X_shards,
mlm_weights_X_shards, mlm_Y_shards, nsp_y_shards)
for l in ls:
l.backward()
trainer.step(1)
mlm_l_mean = sum([float(l) for l in mlm_ls]) / len(mlm_ls)
nsp_l_mean = sum([float(l) for l in nsp_ls]) / len(nsp_ls)
metric.add(mlm_l_mean, nsp_l_mean, batch[0].shape[0], 1)
timer.stop()
if (step + 1) % log_interval == 0:
animator.add(step + 1,
(metric[0] / metric[3], metric[1] / metric[3]))
step += 1
if step == num_steps:
num_steps_reached = True
break
print(f'MLM loss {metric[0] / metric[3]:.3f}, '
f'NSP loss {metric[1] / metric[3]:.3f}')
print(f'{metric[2] / timer.sum():.1f} sentence pairs/sec on {str(ctx)}')
def train(net, train_iter, valid_iter, num_epochs, lr, wd, devices, lr_period,
lr_decay):
# Only train the small custom output network
trainer = gluon.Trainer(net.output_new.collect_params(), 'sgd',
{'learning_rate': lr, 'momentum': 0.9, 'wd': wd})
num_batches, timer = len(train_iter), d2l.Timer()
animator = d2l.Animator(xlabel='epoch', xlim=[1, num_epochs],
legend=['train loss', 'valid loss'])
for epoch in range(num_epochs):
print('Epoch: '+str(epoch+1))
metric = d2l.Accumulator(2)
if epoch > 0 and epoch % lr_period == 0:
trainer.set_learning_rate(trainer.learning_rate * lr_decay)
for i, (features, labels) in enumerate(train_iter):
timer.start()
X_shards, y_shards = d2l.split_batch(features, labels, devices)
output_features = [net.features(X_shard) for X_shard in X_shards]
with autograd.record():
outputs = [net.output_new(feature)
for feature in output_features]
ls = [loss(output, y_shard).sum() for output, y_shard
in zip(outputs, y_shards)]
for l in ls:
l.backward()
trainer.step(batch_size)
metric.add(sum([float(l.sum()) for l in ls]), labels.shape[0])
timer.stop()
if (i + 1) % (num_batches // 5) == 0 or i == num_batches - 1:
animator.add(epoch + (i + 1) / num_batches,
(metric[0] / metric[1], None))
if valid_iter is not None:
valid_loss = evaluate_loss(valid_iter, net, devices)
animator.add(epoch + 1, (None, valid_loss))
if valid_iter is not None:
print(f'train loss {metric[0] / metric[1]:.3f}, '
f'valid loss {valid_loss:.3f}')
else:
print(f'train loss {metric[0] / metric[1]:.3f}')
print(f'{metric[1] * num_epochs / timer.sum():.1f} examples/sec '
f'on {str(devices)}')