def train_phase(predictor, train, valid, args):
# setup iterators
train_iter = iterators.SerialIterator(train, args.batchsize)
valid_iter = iterators.SerialIterator(valid,
args.batchsize,
repeat=False,
shuffle=False)
# setup a model
device = torch.device(args.gpu)
model = Classifier(predictor)
model.to(device)
# setup an optimizer
optimizer = torch.optim.Adam(model.parameters(),
weight_decay=max(args.decay, 0))
# setup a trainer
updater = training.updaters.StandardUpdater(train_iter,
optimizer,
model,
device=device)
trainer = training.Trainer(updater, (args.epoch, 'epoch'), out=args.out)
trainer.extend(extensions.Evaluator(valid_iter, model, device=args.gpu))
# trainer.extend(DumpGraph(model, 'main/loss'))
frequency = args.epoch if args.frequency == -1 else max(1, args.frequency)
trainer.extend(extensions.snapshot(), trigger=(frequency, 'epoch'))
trainer.extend(extensions.LogReport())
if args.plot and extensions.PlotReport.available():
trainer.extend(
extensions.PlotReport(['main/loss', 'validation/main/loss'],
'epoch',
file_name='loss.png'))
trainer.extend(
extensions.PlotReport(
['main/accuracy', 'validation/main/accuracy'],
'epoch',
file_name='accuracy.png'))
trainer.extend(
extensions.PrintReport([
'epoch', 'iteration', 'main/loss', 'validation/main/loss',
'main/accuracy', 'validation/main/accuracy', 'elapsed_time'
]))
trainer.extend(extensions.ProgressBar())
if args.resume:
trainer.load_state_dict(torch.load(args.resume))
trainer.run()
torch.save(predictor.state_dict(), os.path.join(args.out, 'predictor.pth'))
def train_phase(predictor, train, valid, args):
print('# classes:', train.n_classes)
print('# samples:')
print('-- train:', len(train))
print('-- valid:', len(valid))
# setup dataset iterators
train_iter = iterators.MultiprocessIterator(train, args.batchsize)
valid_iter = iterators.SerialIterator(valid,
args.batchsize,
repeat=False,
shuffle=True)
# setup a model
class_weight = None # NOTE: please set if you have..
lossfun = partial(softmax_cross_entropy,
normalize=False,
class_weight=class_weight)
device = torch.device(args.gpu)
model = Classifier(predictor, lossfun=lossfun)
model.to(device)
# setup an optimizer
optimizer = torch.optim.Adam(model.parameters(),
lr=args.lr,
weight_decay=max(args.decay, 0))
# setup a trainer
updater = training.updaters.StandardUpdater(train_iter,
optimizer,
model,
device=device)
trainer = training.Trainer(updater, (args.iteration, 'iteration'),
out=args.out)
frequency = max(args.iteration //
20, 1) if args.frequency == -1 else max(1, args.frequency)
stop_trigger = triggers.EarlyStoppingTrigger(
monitor='validation/main/loss',
max_trigger=(args.iteration, 'iteration'),
check_trigger=(frequency, 'iteration'),
patients=np.inf if args.pinfall == -1 else max(1, args.pinfall))
trainer = training.Trainer(updater, stop_trigger, out=args.out)
# setup a visualizer
transforms = {
'x': lambda x: x,
'y': lambda x: np.argmax(x, axis=0),
't': lambda x: x
}
cmap = np.array([[0, 0, 0], [0, 0, 1]])
cmaps = {'x': None, 'y': cmap, 't': cmap}
clims = {'x': 'minmax', 'y': None, 't': None}
visualizer = ImageVisualizer(transforms=transforms,
cmaps=cmaps,
clims=clims)
# setup a validator
valid_file = os.path.join('validation', 'iter_{.updater.iteration:08}.png')
trainer.extend(Validator(valid_iter,
model,
valid_file,
visualizer=visualizer,
n_vis=20,
device=args.gpu),
trigger=(frequency, 'iteration'))
# trainer.extend(DumpGraph(model, 'main/loss'))
trainer.extend(extensions.snapshot(
filename='snapshot_iter_{.updater.iteration:08}.pth'),
trigger=(frequency, 'iteration'))
trainer.extend(extensions.snapshot_object(
predictor, 'predictor_iter_{.updater.iteration:08}.pth'),
trigger=(frequency, 'iteration'))
log_keys = [
'main/loss', 'validation/main/loss', 'main/accuracy',
'validation/main/accuracy'
]
trainer.extend(LogReport(keys=log_keys))
# setup log ploter
if extensions.PlotReport.available():
for plot_key in ['loss', 'accuracy']:
plot_keys = [
key for key in log_keys
if key.split('/')[-1].startswith(plot_key)
]
trainer.extend(
extensions.PlotReport(plot_keys,
'iteration',
file_name=plot_key + '.png',
trigger=(frequency, 'iteration')))
trainer.extend(
PrintReport(['iteration'] + log_keys + ['elapsed_time'], n_step=100))
trainer.extend(extensions.ProgressBar())
if args.resume:
trainer.load_state_dict(torch.load(args.resume))
# train
trainer.run()
def train_phase(predictor, train, valid, args):
# visualize
plt.rcParams['font.size'] = 18
plt.figure(figsize=(13, 5))
ax = sns.scatterplot(x=train.x.ravel(),
y=train.y.ravel(),
color='blue',
s=55,
alpha=0.3)
ax.plot(train.x.ravel(), train.t.ravel(), color='red', linewidth=2)
ax.set_xlabel('x')
ax.set_ylabel('y')
ax.set_xlim(-10, 10)
ax.set_ylim(-15, 15)
plt.legend(['Ground-truth', 'Observation'])
plt.title('Training data set')
plt.tight_layout()
plt.savefig(os.path.join(args.out, 'train_dataset.png'))
plt.close()
# setup iterators
train_iter = iterators.SerialIterator(train, args.batchsize, shuffle=True)
valid_iter = iterators.SerialIterator(valid,
args.batchsize,
repeat=False,
shuffle=False)
# setup a model
device = torch.device(args.gpu)
lossfun = noised_mean_squared_error
accfun = lambda y, t: F.l1_loss(y[0], t)
model = Regressor(predictor, lossfun=lossfun, accfun=accfun)
model.to(device)
# setup an optimizer
optimizer = torch.optim.Adam(model.parameters(),
weight_decay=max(args.decay, 0))
# setup a trainer
updater = training.updaters.StandardUpdater(train_iter,
optimizer,
model,
device=device)
trainer = training.Trainer(updater, (args.epoch, 'epoch'), out=args.out)
trainer.extend(extensions.Evaluator(valid_iter, model, device=args.gpu))
# trainer.extend(DumpGraph(model, 'main/loss'))
frequency = args.epoch if args.frequency == -1 else max(1, args.frequency)
trainer.extend(extensions.snapshot(), trigger=(frequency, 'epoch'))
trainer.extend(extensions.LogReport())
if args.plot and extensions.PlotReport.available():
trainer.extend(
extensions.PlotReport(['main/loss', 'validation/main/loss'],
'epoch',
file_name='loss.png'))
trainer.extend(
extensions.PlotReport(
['main/accuracy', 'validation/main/accuracy'],
'epoch',
file_name='accuracy.png'))
trainer.extend(
extensions.PlotReport(
['main/predictor/sigma', 'validation/main/predictor/sigma'],
'epoch',
file_name='sigma.png'))
trainer.extend(
extensions.PrintReport([
'epoch', 'iteration', 'main/loss', 'validation/main/loss',
'main/accuracy', 'validation/main/accuracy',
'main/predictor/sigma', 'validation/main/predictor/sigma',
'elapsed_time'
]))
trainer.extend(extensions.ProgressBar())
if args.resume:
trainer.load_state_dict(torch.load(args.resume))
trainer.run()
torch.save(predictor.state_dict(), os.path.join(args.out, 'predictor.pth'))
def main():
parser = argparse.ArgumentParser(description='Chainer example: MNIST')
parser.add_argument('--batchsize',
'-b',
type=int,
default=100,
help='Number of images in each mini-batch')
parser.add_argument('--epoch',
'-e',
type=int,
default=20,
help='Number of sweeps over the dataset to train')
parser.add_argument('--frequency',
'-f',
type=int,
default=-1,
help='Frequency of taking a snapshot')
parser.add_argument('--device',
'-d',
type=str,
default='-1',
help='Device specifier. Either ChainerX device '
'specifier or an integer. If non-negative integer, '
'CuPy arrays with specified device id are used. If '
'negative integer, NumPy arrays are used')
parser.add_argument('--out',
'-o',
default='result',
help='Directory to output the result')
parser.add_argument('--resume',
'-r',
type=str,
help='Resume the training from snapshot')
parser.add_argument('--autoload',
action='store_true',
help='Automatically load trainer snapshots in case'
' of preemption or other temporary system failure')
parser.add_argument('--unit',
'-u',
type=int,
default=1000,
help='Number of units')
group = parser.add_argument_group('deprecated arguments')
group.add_argument('--gpu',
'-g',
dest='device',
type=int,
nargs='?',
const=0,
help='GPU ID (negative value indicates CPU)')
args = parser.parse_args()
device = torch.device(args.device)
print('Device: {}'.format(device))
print('# Minibatch-size: {}'.format(args.batchsize))
print('# epoch: {}'.format(args.epoch))
print('')
# Set up a neural network to train
# Classifier reports softmax cross entropy loss and accuracy at every
# iteration, which will be used by the PrintReport extension below.
model = Classifier(MLP(784, args.unit, 10))
model.to(device)
# Setup an optimizer
optimizer = torch.optim.Adam(model.parameters())
# Load the MNIST dataset
transform = transforms.ToTensor()
train = datasets.MNIST('data',
train=True,
download=True,
transform=transform)
test = datasets.MNIST('data', train=False, transform=transform)
train_iter = pytorch_trainer.iterators.SerialIterator(
train, args.batchsize)
test_iter = pytorch_trainer.iterators.SerialIterator(test,
args.batchsize,
repeat=False,
shuffle=False)
# Set up a trainer
updater = training.updaters.StandardUpdater(train_iter,
optimizer,
model,
device=device)
trainer = training.Trainer(updater, (args.epoch, 'epoch'), out=args.out)
# Evaluate the model with the test dataset for each epoch
trainer.extend(extensions.Evaluator(test_iter, model, device=device),
call_before_training=True)
# Dump a computational graph from 'loss' variable at the first iteration
# The "main" refers to the target link of the "main" optimizer.
# trainer.extend(extensions.DumpGraph('main/loss'))
# Take a snapshot for each specified epoch
frequency = args.epoch if args.frequency == -1 else max(1, args.frequency)
# Take a snapshot each ``frequency`` epoch, delete old stale
# snapshots and automatically load from snapshot files if any
# files are already resident at result directory.
trainer.extend(extensions.snapshot(n_retains=1, autoload=args.autoload),
trigger=(frequency, 'epoch'))
# Write a log of evaluation statistics for each epoch
trainer.extend(extensions.LogReport(), call_before_training=True)
# Save two plot images to the result dir
trainer.extend(extensions.PlotReport(['main/loss', 'validation/main/loss'],
'epoch',
file_name='loss.png'),
call_before_training=True)
trainer.extend(extensions.PlotReport(
['main/accuracy', 'validation/main/accuracy'],
'epoch',
file_name='accuracy.png'),
call_before_training=True)
# Print selected entries of the log to stdout
# Here "main" refers to the target link of the "main" optimizer again, and
# "validation" refers to the default name of the Evaluator extension.
# Entries other than 'epoch' are reported by the Classifier link, called by
# either the updater or the evaluator.
trainer.extend(extensions.PrintReport([
'epoch', 'main/loss', 'validation/main/loss', 'main/accuracy',
'validation/main/accuracy', 'elapsed_time'
]),
call_before_training=True)
# Print a progress bar to stdout
trainer.extend(extensions.ProgressBar())
if args.resume is not None:
# Resume from a snapshot (Note: this loaded model is to be
# overwritten by --autoload option, autoloading snapshots, if
# any snapshots exist in output directory)
trainer.load_state_dict(torch.load(args.resume))
# Run the training
trainer.run()
def train_phase(generator, train, valid, args):
print('# samples:')
print('-- train:', len(train))
print('-- valid:', len(valid))
# setup dataset iterators
train_iter = iterators.SerialIterator(train, args.batchsize)
valid_iter = iterators.SerialIterator(valid, args.batchsize,
repeat=False, shuffle=True)
# setup a model
model = Regressor(generator,
activation=torch.tanh,
lossfun=F.l1_loss,
accfun=F.l1_loss)
discriminator = build_discriminator()
discriminator.save_args(os.path.join(args.out, 'discriminator.json'))
device = torch.device(args.gpu)
model.to(device)
discriminator.to(device)
# setup an optimizer
optimizer_G = torch.optim.Adam(model.parameters(),
lr=args.lr,
betas=(args.beta, 0.999),
weight_decay=max(args.decay, 0))
optimizer_D = torch.optim.Adam(discriminator.parameters(),
lr=args.lr,
betas=(args.beta, 0.999),
weight_decay=max(args.decay, 0))
# setup a trainer
updater = DCGANUpdater(
iterator=train_iter,
optimizer={
'gen': optimizer_G,
'dis': optimizer_D,
},
model={
'gen': model,
'dis': discriminator,
},
alpha=args.alpha,
device=args.gpu,
)
frequency = max(args.iteration//80, 1) if args.frequency == -1 else max(1, args.frequency)
stop_trigger = triggers.EarlyStoppingTrigger(monitor='validation/main/loss',
max_trigger=(args.iteration, 'iteration'),
check_trigger=(frequency, 'iteration'),
patients=np.inf if args.pinfall == -1 else max(1, args.pinfall))
trainer = training.Trainer(updater, stop_trigger, out=args.out)
# shift lr
trainer.extend(
extensions.LinearShift('lr', (args.lr, 0.0),
(args.iteration//2, args.iteration),
optimizer=optimizer_G))
trainer.extend(
extensions.LinearShift('lr', (args.lr, 0.0),
(args.iteration//2, args.iteration),
optimizer=optimizer_D))
# setup a visualizer
transforms = {'x': lambda x: x, 'y': lambda x: x, 't': lambda x: x}
clims = {'x': (-1., 1.), 'y': (-1., 1.), 't': (-1., 1.)}
visualizer = ImageVisualizer(transforms=transforms,
cmaps=None,
clims=clims)
# setup a validator
valid_file = os.path.join('validation', 'iter_{.updater.iteration:08}.png')
trainer.extend(Validator(valid_iter, model, valid_file,
visualizer=visualizer, n_vis=20,
device=args.gpu),
trigger=(frequency, 'iteration'))
# trainer.extend(DumpGraph('loss_gen', filename='generative_loss.dot'))
# trainer.extend(DumpGraph('loss_cond', filename='conditional_loss.dot'))
# trainer.extend(DumpGraph('loss_dis', filename='discriminative_loss.dot'))
trainer.extend(extensions.snapshot(filename='snapshot_iter_{.updater.iteration:08}.pth'),
trigger=(frequency, 'iteration'))
trainer.extend(extensions.snapshot_object(generator, 'generator_iter_{.updater.iteration:08}.pth'),
trigger=(frequency, 'iteration'))
trainer.extend(extensions.snapshot_object(discriminator, 'discriminator_iter_{.updater.iteration:08}.pth'),
trigger=(frequency, 'iteration'))
log_keys = ['loss_gen', 'loss_cond', 'loss_dis',
'validation/main/accuracy']
trainer.extend(LogReport(keys=log_keys, trigger=(100, 'iteration')))
# setup log ploter
if extensions.PlotReport.available():
for plot_key in ['loss', 'accuracy']:
plot_keys = [key for key in log_keys if key.split('/')[-1].startswith(plot_key)]
trainer.extend(
extensions.PlotReport(plot_keys,
'iteration', file_name=plot_key + '.png',
trigger=(frequency, 'iteration')) )
trainer.extend(PrintReport(['iteration'] + log_keys + ['elapsed_time'], n_step=1))
trainer.extend(extensions.ProgressBar())
if args.resume:
trainer.load_state_dict(torch.load(args.resume))
# train
trainer.run()