def get_progbar(model, count_mode):
"""Get Progbar."""
stateful_metric_names = None
if hasattr(model, 'metrics_names'):
stateful_metric_names = model.metrics_names[1:] # Exclude `loss`
return cbks.ProgbarLogger(count_mode,
stateful_metrics=stateful_metric_names)
def test_validate_callbacks_predefined_callbacks(self):
supported_predefined_callbacks = [
callbacks.TensorBoard(),
callbacks.CSVLogger(filename='./log.csv'),
callbacks.EarlyStopping(),
callbacks.ModelCheckpoint(filepath='./checkpoint'),
callbacks.TerminateOnNaN(),
callbacks.ProgbarLogger(),
callbacks.History(),
callbacks.RemoteMonitor()
]
distributed_training_utils.validate_callbacks(
supported_predefined_callbacks, adam.Adam())
unsupported_predefined_callbacks = [
callbacks.ReduceLROnPlateau(),
callbacks.LearningRateScheduler(schedule=lambda epoch: 0.001)
]
for callback in unsupported_predefined_callbacks:
with self.assertRaisesRegex(ValueError,
'You must specify a Keras Optimizer V2'):
distributed_training_utils.validate_callbacks([callback],
v1_adam.AdamOptimizer())
def fit_loop(model,
inputs,
targets,
sample_weights=None,
class_weight=None,
val_inputs=None,
val_targets=None,
val_sample_weights=None,
batch_size=None,
epochs=1,
verbose=1,
callbacks=None,
shuffle=True,
callback_metrics=None,
initial_epoch=0,
steps_per_epoch=None,
validation_steps=None):
"""Fit function for eager execution.
Arguments:
model: Instance of the model that is being executed in Eager mode.
inputs: List of input arrays.
targets: List of target arrays.
sample_weights: Optional list of sample weight arrays.
class_weight: Optional class-weight array to weight the importance of
samples in `inputs` based on the class they belong to, as conveyed by
`targets`.
val_inputs: Input data for validation.
val_targets: Target data for validation.
val_sample_weights: Sample weight data for validation.
batch_size: Integer batch size or None if unknown.
epochs: Number of times to iterate over the data
verbose: Verbosity mode, 0, 1 or 2
callbacks: List of callbacks to be called during training
shuffle: Whether to shuffle the data at the beginning of each epoch
callback_metrics: List of strings, the display names of the metrics
passed to the callbacks. They should be the
concatenation of list the display names of the outputs of
`f` and the list of display names of the outputs of `f_val`.
initial_epoch: Epoch at which to start training
(useful for resuming a previous training run)
steps_per_epoch: Total number of steps (batches of samples)
before declaring one epoch finished and starting the
next epoch. Ignored with the default value of `None`.
validation_steps: Number of steps to run validation for (only if doing
validation from data tensors). Ignored with default value of `None`.
Returns:
`History` object.
Raises:
ValueError: In case of invalid argument values.
"""
# Convert training inputs to an EagerIterator
inputs, steps_per_epoch = training_utils.convert_to_iterator(
x=inputs,
y=targets,
sample_weights=sample_weights,
batch_size=batch_size,
steps_per_epoch=steps_per_epoch,
epochs=epochs,
shuffle=shuffle)
# Required for eager execution
with backend.learning_phase_scope(1):
do_validation = False
if val_inputs:
do_validation = True
num_train_samples = None
out_labels = None
if model._is_compiled:
out_labels = model.metrics_names
if do_validation:
callback_metrics = copy.copy(out_labels) + [
'val_' + n for n in out_labels
]
else:
callback_metrics = copy.copy(out_labels)
model.history = cbks.History()
callbacks = [cbks.BaseLogger()] + (callbacks or []) + [model.history]
if verbose:
callbacks += [cbks.ProgbarLogger('steps')]
callbacks = cbks.CallbackList(callbacks)
# it's possible to callback a different model than self
# (used by Sequential models)
if hasattr(model, 'callback_model') and model.callback_model:
callback_model = model.callback_model
else:
callback_model = model
callbacks.set_model(callback_model)
callback_params = {
'batch_size': batch_size,
'epochs': epochs,
'steps': steps_per_epoch,
'samples': num_train_samples,
'verbose': verbose,
'do_validation': do_validation,
'metrics': callback_metrics or [],
}
if validation_steps:
callback_params.update({'validation_steps': validation_steps})
callbacks.set_params(callback_params)
for cbk in callbacks:
if not val_inputs:
cbk.validation_data = []
elif isinstance(val_inputs, iterator_ops.EagerIterator):
cbk.validation_data = val_inputs
elif val_sample_weights:
cbk.validation_data = val_inputs + val_targets + val_sample_weights
else:
cbk.validation_data = val_inputs + val_targets
# validation_data must be set before on_train_begin() is called
# so that TensorboardCallback can validate its input
callbacks.on_train_begin()
callback_model.stop_training = False
for epoch in range(initial_epoch, epochs):
callbacks.on_epoch_begin(epoch)
epoch_logs = {}
iterator_fit_loop(model,
inputs,
class_weight,
steps_per_epoch=steps_per_epoch,
callback_model=callback_model,
out_labels=out_labels,
epoch_logs=epoch_logs,
val_inputs=val_inputs,
val_targets=val_targets,
val_sample_weights=val_sample_weights,
epochs=epochs,
verbose=verbose,
callbacks=callbacks,
callback_metrics=callback_metrics,
validation_steps=validation_steps,
do_validation=do_validation,
batch_size=batch_size)
callbacks.on_epoch_end(epoch, epoch_logs)
if callback_model.stop_training:
break
callbacks.on_train_end()
return model.history
def fit_loop(model,
inputs,
targets,
sample_weights=None,
batch_size=None,
epochs=100,
verbose=1,
callbacks=None,
val_inputs=None,
val_targets=None,
val_sample_weights=None,
shuffle=True,
callback_metrics=None,
initial_epoch=0,
steps_per_epoch=None,
validation_steps=None):
"""Abstract fit function for arrays of data.
Arguments:
model: Keras Model instance.
inputs: List of input arrays.
targets: List of target arrays.
sample_weights: Optional list of sample weight arrays.
batch_size: Integer batch size or None if unknown.
epochs: Number of times to iterate over the data
verbose: Verbosity mode, 0, 1 or 2
callbacks: List of callbacks to be called during training
val_inputs: List of input arrays.
val_targets: List of target arrays.
val_sample_weights: Optional list of sample weight arrays.
shuffle: Whether to shuffle the data at the beginning of each epoch
callback_metrics: List of strings, the display names of the metrics
passed to the callbacks. They should be the
concatenation of list the display names of the outputs of
`f` and the list of display names of the outputs of `f_val`.
initial_epoch: Epoch at which to start training
(useful for resuming a previous training run)
steps_per_epoch: Total number of steps (batches of samples)
before declaring one epoch finished and starting the
next epoch. Ignored with the default value of `None`.
validation_steps: Number of steps to run validation for
(only if doing validation from data tensors).
Ignored with the default value of `None`.
Returns:
`History` object.
Raises:
ValueError: in case of invalid arguments.
"""
model._make_train_function()
f = model.train_function
sample_weights = sample_weights or []
val_sample_weights = val_sample_weights or []
if model.uses_learning_phase and not isinstance(K.learning_phase(), int):
ins = inputs + targets + sample_weights + [1]
if val_inputs:
val_ins = val_inputs + val_targets + val_sample_weights + [1]
else:
ins = inputs + targets + sample_weights
if val_inputs:
val_ins = val_inputs + val_targets + val_sample_weights
if not val_inputs:
val_ins = []
do_validation = False
if val_inputs:
do_validation = True
if (steps_per_epoch is None and verbose and inputs
and hasattr(inputs[0], 'shape')
and hasattr(val_inputs[0], 'shape')):
print('Train on %d samples, validate on %d samples' %
(inputs[0].shape[0], val_inputs[0].shape[0]))
if validation_steps:
do_validation = True
if steps_per_epoch is None:
raise ValueError('Can only use `validation_steps` '
'when doing step-wise '
'training, i.e. `steps_per_epoch` '
'must be set.')
out_labels = model.metrics_names
if do_validation:
callback_metrics = copy.copy(out_labels) + [
'val_' + n for n in out_labels
]
else:
callback_metrics = copy.copy(out_labels)
num_train_samples = training_utils.check_num_samples(
ins, batch_size, steps_per_epoch, 'steps_per_epoch')
if num_train_samples is not None:
index_array = np.arange(num_train_samples)
model.history = cbks.History()
all_callbacks = [
cbks.BaseLogger(stateful_metrics=model.stateful_metric_names)
]
if verbose:
if steps_per_epoch is not None:
count_mode = 'steps'
else:
count_mode = 'samples'
all_callbacks.append(
cbks.ProgbarLogger(count_mode,
stateful_metrics=model.stateful_metric_names))
all_callbacks += (callbacks or []) + [model.history]
callbacks = cbks.CallbackList(all_callbacks)
out_labels = out_labels or []
# it's possible to callback a different model than self
# (used by Sequential models)
if hasattr(model, 'callback_model') and model.callback_model:
callback_model = model.callback_model
else:
callback_model = model
callbacks.set_model(callback_model)
callbacks.set_params({
'batch_size': batch_size,
'epochs': epochs,
'steps': steps_per_epoch,
'samples': num_train_samples,
'verbose': verbose,
'do_validation': do_validation,
'metrics': callback_metrics or [],
})
callbacks.on_train_begin()
callback_model.stop_training = False
for cbk in callbacks:
cbk.validation_data = val_ins
# To prevent a slowdown, we find beforehand the arrays that need conversion.
feed = model._feed_inputs + model._feed_targets + model._feed_sample_weights
indices_for_conversion_to_dense = []
for i in range(len(feed)):
if issparse is not None and issparse(
ins[i]) and not K.is_sparse(feed[i]):
indices_for_conversion_to_dense.append(i)
for epoch in range(initial_epoch, epochs):
# Reset stateful metrics
for m in model.stateful_metric_functions:
m.reset_states()
# Update callbacks
callbacks.on_epoch_begin(epoch)
epoch_logs = {}
if steps_per_epoch is not None:
for step_index in range(steps_per_epoch):
batch_logs = {}
batch_logs['batch'] = step_index
batch_logs['size'] = 1
callbacks.on_batch_begin(step_index, batch_logs)
try:
outs = f(ins)
except errors.OutOfRangeError:
logging.warning(
'Your dataset iterator ran out of data; '
'interrupting training. Make sure that your dataset '
'can generate at least `steps_per_epoch * epochs` '
'batches (in this case, %d batches).' %
steps_per_epoch * epochs)
break
if not isinstance(outs, list):
outs = [outs]
for l, o in zip(out_labels, outs):
batch_logs[l] = o
callbacks.on_batch_end(step_index, batch_logs)
if callback_model.stop_training:
break
if do_validation:
val_outs = test_loop(model,
val_inputs,
val_targets,
sample_weights=val_sample_weights,
batch_size=batch_size,
steps=validation_steps,
verbose=0)
if not isinstance(val_outs, list):
val_outs = [val_outs]
# Same labels assumed.
for l, o in zip(out_labels, val_outs):
epoch_logs['val_' + l] = o
else:
if shuffle == 'batch':
index_array = training_utils.batch_shuffle(
index_array, batch_size)
elif shuffle:
np.random.shuffle(index_array)
batches = make_batches(num_train_samples, batch_size)
for batch_index, (batch_start, batch_end) in enumerate(batches):
batch_ids = index_array[batch_start:batch_end]
try:
if isinstance(ins[-1], int):
# Do not slice the training phase flag.
ins_batch = slice_arrays(ins[:-1],
batch_ids) + [ins[-1]]
else:
ins_batch = slice_arrays(ins, batch_ids)
except TypeError:
raise TypeError('TypeError while preparing batch. '
'If using HDF5 input data, '
'pass shuffle="batch".')
batch_logs = {}
batch_logs['batch'] = batch_index
batch_logs['size'] = len(batch_ids)
callbacks.on_batch_begin(batch_index, batch_logs)
for i in indices_for_conversion_to_dense:
ins_batch[i] = ins_batch[i].toarray()
outs = f(ins_batch)
if not isinstance(outs, list):
outs = [outs]
for l, o in zip(out_labels, outs):
batch_logs[l] = o
callbacks.on_batch_end(batch_index, batch_logs)
if callback_model.stop_training:
break
if batch_index == len(batches) - 1: # Last batch.
if do_validation:
val_outs = test_loop(model,
val_inputs,
val_targets,
sample_weights=val_sample_weights,
batch_size=batch_size,
verbose=0)
if not isinstance(val_outs, list):
val_outs = [val_outs]
# Same labels assumed.
for l, o in zip(out_labels, val_outs):
epoch_logs['val_' + l] = o
callbacks.on_epoch_end(epoch, epoch_logs)
if callback_model.stop_training:
break
callbacks.on_train_end()
return model.history
def fit_loop(model,
inputs,
targets,
epochs=100,
verbose=1,
callbacks=None,
val_inputs=None,
val_targets=None,
callback_metrics=None,
initial_epoch=0,
steps_per_epoch=None,
validation_steps=None):
"""fit function when using DistributionStrategy for training.
Arguments:
model: Keras Model instance.
inputs: List of input arrays.
targets: List of target arrays.
epochs: Number of times to iterate over the data
verbose: Verbosity mode, 0, 1 or 2
callbacks: List of callbacks to be called during training
val_inputs: List of input arrays.
val_targets: List of target arrays.
callback_metrics: List of strings, the display names of the metrics
passed to the callbacks. They should be the
concatenation of list the display names of the outputs of
`f` and the list of display names of the outputs of `f_val`.
initial_epoch: Epoch at which to start training
(useful for resuming a previous training run)
steps_per_epoch: Total number of steps (batches of samples)
before declaring one epoch finished and starting the
next epoch. Ignored with the default value of `None`.
validation_steps: Number of steps to run validation for
(only if doing validation from data tensors).
Ignored with the default value of `None`.
Returns:
`History` object.
Raises:
ValueError: in case of invalid arguments.
"""
current_strategy = model._distribution_strategy
def _per_device_train_function(model):
model._make_train_function()
return (model.train_function.inputs, model.train_function.outputs,
model.train_function.updates_op,
model.train_function.session_kwargs)
with current_strategy.scope():
# Create train ops on each of the devices when we call
# `_per_device_train_function`.
(grouped_inputs, grouped_outputs, grouped_updates,
grouped_session_args) = current_strategy.call_for_each_tower(
_per_device_train_function, model._grouped_model)
# Unwrap all the per device values returned from `call_for_each_tower`.
# Unwrapping per device values gives you a list of values that can be
# used to construct a new train function that is composed of update ops on
# all the devices over which the model is distributed.
(all_inputs, all_outputs, all_updates,
all_session_args) = distributed_training_utils.unwrap_values(
current_strategy,
grouped_inputs,
grouped_outputs,
grouped_updates,
grouped_session_args,
with_loss_tensor=True)
# Dataset inputs and targets are also per devices values that need to be
# unwrapped.
dataset_inputs = distributed_training_utils.flatten_perdevice_values(
current_strategy, inputs)
dataset_targets = distributed_training_utils.flatten_perdevice_values(
current_strategy, targets)
# Create a train function that is composed of all the parameters above.
distributed_train_function = K.Function(all_inputs,
all_outputs,
updates=all_updates,
name='distributed_train_function',
**all_session_args)
# We need to set sample_weights to None since there are sample weight
# placeholders that are created with default values.
sample_weights = [
None for _ in range(len(model.outputs) * current_strategy.num_towers)
]
if model.uses_learning_phase and not isinstance(K.learning_phase(), int):
ins = dataset_inputs + dataset_targets + sample_weights + [1]
else:
ins = dataset_inputs + dataset_targets
do_validation = False
if validation_steps:
do_validation = True
if steps_per_epoch is None:
raise ValueError('Can only use `validation_steps` '
'when doing step-wise '
'training, i.e. `steps_per_epoch` '
'must be set.')
out_labels = model.metrics_names
if do_validation:
callback_metrics = copy.copy(out_labels) + [
'val_' + n for n in out_labels
]
else:
callback_metrics = copy.copy(out_labels)
model.history = cbks.History()
all_callbacks = [
cbks.BaseLogger(stateful_metrics=model.stateful_metric_names)
]
if verbose:
# We assume that `steps_per_epoch` is always set since we have to use
# Datasets.
count_mode = 'steps'
all_callbacks.append(
cbks.ProgbarLogger(count_mode,
stateful_metrics=model.stateful_metric_names))
all_callbacks += (callbacks or []) + [model.history]
callbacks = cbks.CallbackList(all_callbacks)
out_labels = out_labels or []
# We set the callback model to an instance of the `DistributedModel` that we
# create in the `compile` call. The `DistributedModel` is initialized with
# the first replicated model. We need to set the callback model to a
# DistributedModel to allow us to override saving and loading weights when
# we checkpoint the model during training.
callback_model = model._replicated_model
callbacks.set_model(callback_model)
callbacks.set_params({
'epochs': epochs,
'steps': steps_per_epoch,
'samples': None,
'verbose': verbose,
'do_validation': do_validation,
'metrics': callback_metrics or [],
})
callbacks.on_train_begin()
callback_model.stop_training = False
out_labels = out_labels or []
# Copy the weights from the original model to each of the replicated models.
orig_model_weights = model.get_weights()
with current_strategy.scope():
distributed_model = current_strategy.unwrap(model._grouped_model)[0]
distributed_training_utils.set_weights(current_strategy,
distributed_model,
orig_model_weights)
for epoch in range(initial_epoch, epochs):
callbacks.on_epoch_begin(epoch)
if steps_per_epoch is not None:
epoch_logs = {}
for step_index in range(steps_per_epoch):
batch_logs = {}
batch_logs['batch'] = step_index
batch_logs['size'] = 1
callbacks.on_batch_begin(step_index, batch_logs)
try:
outs = distributed_train_function(ins)
except errors.OutOfRangeError:
logging.warning(
'Your dataset iterator ran out of data; '
'interrupting training. Make sure that your dataset '
'can generate at least `steps_per_epoch * epochs` '
'batches (in this case, %d batches).' %
steps_per_epoch * epochs)
break
if not isinstance(outs, list):
outs = [outs]
# TODO(anjalisridhar): Temporary workaround for aggregating metrics
# across towers. Replace with the new metrics module eventually.
merged_output = []
# The first output is the total loss.
merged_output.append(outs[0])
current_index = 1
num_devices = len(current_strategy._devices)
# Each label in `out_labels` corresponds to one set of metrics. The
# number of metric values corresponds to the number of devices. We
# currently take the mean of the values.
for _ in out_labels[1:]:
m = np.mean(outs[current_index:current_index +
num_devices])
merged_output.append(m)
current_index += num_devices
for l, o in zip(out_labels, outs):
batch_logs[l] = o
callbacks.on_batch_end(step_index, batch_logs)
if callback_model.stop_training:
break
if do_validation:
val_outs = test_loop(model,
val_inputs,
val_targets,
steps=validation_steps,
verbose=0)
if not isinstance(val_outs, list):
val_outs = [val_outs]
# Same labels assumed.
for l, o in zip(out_labels, val_outs):
epoch_logs['val_' + l] = o
callbacks.on_epoch_end(epoch, epoch_logs)
if callback_model.stop_training:
break
callbacks.on_train_end()
# Copy the weights back from the replicated model to the original model.
with current_strategy.scope():
updated_weights = current_strategy.unwrap(
model._grouped_model)[0].get_weights()
model.set_weights(updated_weights)
return model.history
def fit_generator(model,
generator,
steps_per_epoch=None,
epochs=1,
verbose=1,
callbacks=None,
validation_data=None,
validation_steps=None,
class_weight=None,
max_queue_size=10,
workers=1,
use_multiprocessing=False,
shuffle=True,
initial_epoch=0):
"""See docstring for `Model.fit_generator`."""
wait_time = 0.01 # in seconds
epoch = initial_epoch
do_validation = bool(validation_data)
is_sequence = isinstance(generator, Sequence)
if not is_sequence and use_multiprocessing and workers > 1:
logging.warning(
UserWarning('Using a generator with `use_multiprocessing=True`'
' and multiple workers may duplicate your data.'
' Please consider using the`keras.utils.Sequence'
' class.'))
if steps_per_epoch is None:
if is_sequence:
steps_per_epoch = len(generator)
else:
raise ValueError('`steps_per_epoch=None` is only valid for a'
' generator based on the `keras.utils.Sequence`'
' class. Please specify `steps_per_epoch` or use'
' the `keras.utils.Sequence` class.')
# python 2 has 'next', 3 has '__next__'
# avoid any explicit version checks
val_gen = (
hasattr(validation_data, 'next') or
hasattr(validation_data, '__next__') or
isinstance(validation_data, Sequence))
if (val_gen and not isinstance(validation_data, Sequence) and
not validation_steps):
raise ValueError('`validation_steps=None` is only valid for a'
' generator based on the `keras.utils.Sequence`'
' class. Please specify `validation_steps` or use'
' the `keras.utils.Sequence` class.')
# Prepare display labels.
out_labels = model.metrics_names
callback_metrics = out_labels + ['val_%s' % n for n in out_labels]
# prepare callbacks
model.history = cbks.History()
callbacks = [cbks.BaseLogger()] + (callbacks or []) + [model.history]
if verbose:
callbacks += [cbks.ProgbarLogger(count_mode='steps')]
callbacks = cbks.CallbackList(callbacks)
# it's possible to callback a different model than self:
if hasattr(model, 'callback_model') and model.callback_model:
callback_model = model.callback_model
else:
callback_model = model
callbacks.set_model(callback_model)
callback_params = {
'epochs': epochs,
'steps': steps_per_epoch,
'verbose': verbose,
'do_validation': do_validation,
'metrics': callback_metrics,
}
if do_validation:
# need to create the test_function before start of the first epoch
# because TensorBoard callback on_epoch_begin adds summary to the
# list of fetches of the test_function
model._make_test_function()
# determine the number of validation batches given a generator
if validation_steps:
callback_params.update({'validation_steps': validation_steps})
elif isinstance(validation_data, Sequence):
callback_params.update({'validation_steps': len(validation_data)})
callbacks.set_params(callback_params)
enqueuer = None
val_enqueuer = None
try:
if do_validation and not val_gen:
# Prepare data for validation
if len(validation_data) == 2:
val_x, val_y = validation_data # pylint: disable=unpacking-non-sequence
val_sample_weight = None
elif len(validation_data) == 3:
val_x, val_y, val_sample_weight = validation_data # pylint: disable=unpacking-non-sequence
else:
raise ValueError(
'`validation_data` should be a tuple '
'`(val_x, val_y, val_sample_weight)` '
'or `(val_x, val_y)`. Found: ' + str(validation_data))
val_x, val_y, val_sample_weights = model._standardize_user_data(
val_x, val_y, val_sample_weight)
val_data = val_x + val_y + val_sample_weights
if model.uses_learning_phase and not isinstance(K.learning_phase(), int):
val_data += [0.]
for cbk in callbacks:
cbk.validation_data = val_data
if workers > 0:
if is_sequence:
enqueuer = OrderedEnqueuer(
generator,
use_multiprocessing=use_multiprocessing,
shuffle=shuffle)
else:
enqueuer = GeneratorEnqueuer(
generator,
use_multiprocessing=use_multiprocessing,
wait_time=wait_time)
enqueuer.start(workers=workers, max_queue_size=max_queue_size)
output_generator = enqueuer.get()
else:
if is_sequence:
output_generator = iter(generator)
else:
output_generator = generator
callback_model.stop_training = False
# validation_data must be set before on_train_begin() is called
# so that TensorboardCallback can validate its input
callbacks.on_train_begin()
# Construct epoch logs.
epoch_logs = {}
while epoch < epochs:
for m in model.stateful_metric_functions:
m.reset_states()
callbacks.on_epoch_begin(epoch)
steps_done = 0
batch_index = 0
while steps_done < steps_per_epoch:
generator_output = next(output_generator)
if not hasattr(generator_output, '__len__'):
raise ValueError('Output of generator should be '
'a tuple `(x, y, sample_weight)` '
'or `(x, y)`. Found: ' + str(generator_output))
if len(generator_output) == 2:
x, y = generator_output
sample_weight = None
elif len(generator_output) == 3:
x, y, sample_weight = generator_output
else:
raise ValueError('Output of generator should be '
'a tuple `(x, y, sample_weight)` '
'or `(x, y)`. Found: ' + str(generator_output))
# build batch logs
batch_logs = {}
if isinstance(x, list):
batch_size = x[0].shape[0]
elif isinstance(x, dict):
batch_size = list(x.values())[0].shape[0]
else:
batch_size = x.shape[0]
batch_logs['batch'] = batch_index
batch_logs['size'] = batch_size
callbacks.on_batch_begin(batch_index, batch_logs)
outs = model.train_on_batch(
x, y, sample_weight=sample_weight, class_weight=class_weight)
if not isinstance(outs, list):
outs = [outs]
for l, o in zip(out_labels, outs):
batch_logs[l] = o
callbacks.on_batch_end(batch_index, batch_logs)
batch_index += 1
steps_done += 1
# Epoch finished.
if steps_done >= steps_per_epoch and do_validation:
if val_gen:
val_outs = evaluate_generator(
model,
validation_data,
validation_steps,
workers=workers,
use_multiprocessing=use_multiprocessing,
max_queue_size=max_queue_size)
else:
# No need for try/except because
# data has already been validated.
val_outs = model.evaluate(
val_x,
val_y,
batch_size=batch_size,
sample_weight=val_sample_weights,
verbose=0)
if not isinstance(val_outs, list):
val_outs = [val_outs]
# Same labels assumed.
for l, o in zip(out_labels, val_outs):
epoch_logs['val_' + l] = o
if callback_model.stop_training:
break
callbacks.on_epoch_end(epoch, epoch_logs)
epoch += 1
if callback_model.stop_training:
break
finally:
try:
if enqueuer is not None:
enqueuer.stop()
finally:
if val_enqueuer is not None:
val_enqueuer.stop()
callbacks.on_train_end()
return model.history
def train_model(name,
g_train,
d_train,
sampler,
generator,
samples_per_epoch,
epochs,
z_dim=100,
verbose=1,
callbacks=[],
saver=None):
"""
Main training loop.
Modified version of fit_generator.
"""
self = {}
epoch = 0
counter = 0
out_labels = ['g_loss', 'd_loss', 'd_loss_fake', 'd_loss_legit',
'time'] # self.metrics_names
callback_metrics = out_labels + ['val_' + n for n in out_labels]
# prepare callbacks
history = cbks.History()
callbacks = [cbks.BaseLogger()] + callbacks + [history]
if verbose:
callbacks += [cbks.ProgbarLogger()]
callbacks = cbks.CallbackList(callbacks)
callback_params = {
'epochs': epochs,
'samples': samples_per_epoch,
'verbose': verbose,
'metrics': callback_metrics,
}
callbacks.set_params(callback_params)
callbacks.on_train_begin()
while epoch < epochs:
callbacks.on_epoch_begin(epoch)
samples_seen = 0
batch_index = 0
while samples_seen < samples_per_epoch:
z, x = next(generator)
# build batch logs
batch_logs = {}
if type(x) is list:
batch_size = len(x[0])
elif type(x) is dict:
batch_size = len(list(x.values())[0])
else:
batch_size = len(x)
batch_logs['batch'] = batch_index
batch_logs['size'] = batch_size
callbacks.on_batch_begin(batch_index, batch_logs)
t1 = time.time()
d_losses = d_train(x, z, counter)
z, x = next(generator)
g_loss, samples, xs = g_train(x, z, counter)
outs = (g_loss, ) + d_losses + (time.time() - t1, )
counter += 1
# save samples
if batch_index % 100 == 0:
join_image = np.zeros_like(
np.concatenate([samples[:64], xs[:64]], axis=0))
for j, (i1, i2) in enumerate(zip(samples[:64], xs[:64])):
join_image[j * 2] = i1
join_image[j * 2 + 1] = i2
save_images(
join_image, [8 * 2, 8],
'./outputs/samples_%s/train_%s_%s.png' %
(name, epoch, batch_index))
samples, xs = sampler(z, x)
join_image = np.zeros_like(
np.concatenate([samples[:64], xs[:64]], axis=0))
for j, (i1, i2) in enumerate(zip(samples[:64], xs[:64])):
join_image[j * 2] = i1
join_image[j * 2 + 1] = i2
save_images(
join_image, [8 * 2, 8],
'./outputs/samples_%s/test_%s_%s.png' %
(name, epoch, batch_index))
for l, o in zip(out_labels, outs):
batch_logs[l] = o
callbacks.on_batch_end(batch_index, batch_logs)
# construct epoch logs
epoch_logs = {}
batch_index += 1
samples_seen += batch_size
if saver is not None:
saver(epoch)
callbacks.on_epoch_end(epoch, epoch_logs)
epoch += 1
# _stop.set()
callbacks.on_train_end()
