new_callback_class()
is an alias for Callback()
.
See ?
Callback()
for the full documentation.
new_callback_class(
classname,
on_epoch_begin = NULL,
on_epoch_end = NULL,
on_train_begin = NULL,
on_train_end = NULL,
on_train_batch_begin = NULL,
on_train_batch_end = NULL,
on_test_begin = NULL,
on_test_end = NULL,
on_test_batch_begin = NULL,
on_test_batch_end = NULL,
on_predict_begin = NULL,
on_predict_end = NULL,
on_predict_batch_begin = NULL,
on_predict_batch_end = NULL,
...,
public = list(),
private = list(),
inherit = NULL,
parent_env = parent.frame()
)
A function that returns the custom Callback
instances,
similar to the builtin callback functions.
String, the name of the custom class. (Conventionally, CamelCase).
\(epoch, logs = NULL)
Called at the start of an epoch.
Subclasses should override for any actions to run. This function should only be called during TRAIN mode.
Args:
epoch
: Integer, index of epoch.
logs
: Named List. Currently no data is passed to this argument for this
method but that may change in the future.
\(epoch, logs = NULL)
Called at the end of an epoch.
Subclasses should override for any actions to run. This function should only be called during TRAIN mode.
Args:
epoch
: Integer, index of epoch.
logs
: Named List, metric results for this training epoch, and for the
validation epoch if validation is performed. Validation result
keys are prefixed with val_
. For training epoch, the values of
the Model
's metrics are returned. Example:
list(loss = 0.2, accuracy = 0.7)
.
\(logs = NULL)
Called at the beginning of training.
Subclasses should override for any actions to run.
Args:
logs
: Named list. Currently no data is passed to this argument for this
method but that may change in the future.
\(logs = NULL)
Called at the end of training.
Subclasses should override for any actions to run.
Args:
logs
: Named list. Currently the output of the last call to
on_epoch_end()
is passed to this argument for this method but
that may change in the future.
\(batch, logs = NULL)
Called at the beginning of a training batch in fit()
methods.
Subclasses should override for any actions to run.
Note that if the steps_per_execution
argument to compile
in
Model
is set to N
, this method will only be called every
N
batches.
Args:
batch
: Integer, index of batch within the current epoch.
logs
: Named list. Currently no data is passed to this argument for this
method but that may change in the future.
\(batch, logs=NULL)
Called at the end of a training batch in fit()
methods.
Subclasses should override for any actions to run.
Note that if the steps_per_execution
argument to compile
in
Model
is set to N
, this method will only be called every
N
batches.
Args:
batch
: Integer, index of batch within the current epoch.
logs
: Named list. Aggregated metric results up until this batch.
\(logs = NULL)
Called at the beginning of evaluation or validation.
Subclasses should override for any actions to run.
Args:
logs
: Named list. Currently no data is passed to this argument for this
method but that may change in the future.
\(logs = NULL)
Called at the end of evaluation or validation.
Subclasses should override for any actions to run.
Args:
logs
: Named list. Currently the output of the last call to
on_test_batch_end()
is passed to this argument for this method
but that may change in the future.
\(batch, logs = NULL)
Called at the beginning of a batch in evaluate()
methods.
Also called at the beginning of a validation batch in the fit()
methods, if validation data is provided.
Subclasses should override for any actions to run.
Note that if the steps_per_execution
argument to compile()
in
Model
is set to N
, this method will only be called every
N
batches.
Args:
batch
: Integer, index of batch within the current epoch.
logs
: Named list. Currently no data is passed to this argument for this
method but that may change in the future.
\(batch, logs = NULL)
Called at the end of a batch in evaluate()
methods.
Also called at the end of a validation batch in the fit()
methods, if validation data is provided.
Subclasses should override for any actions to run.
Note that if the steps_per_execution
argument to compile()
in
Model
is set to N
, this method will only be called every
N
batches.
Args:
batch
: Integer, index of batch within the current epoch.
logs
: Named list. Aggregated metric results up until this batch.
\(logs = NULL)
Called at the beginning of prediction.
Subclasses should override for any actions to run.
Args:
logs
: Named list. Currently no data is passed to this argument for this
method but that may change in the future.
\(logs = NULL)
Called at the end of prediction.
Subclasses should override for any actions to run.
Args:
logs
: Named list. Currently no data is passed to this argument for this
method but that may change in the future.
\(batch, logs = NULL)
Called at the beginning of a batch in predict()
methods.
Subclasses should override for any actions to run.
Note that if the steps_per_execution
argument to compile()
in
Model
is set to N
, this method will only be called every
N
batches.
Args:
batch
: Integer, index of batch within the current epoch.
logs
: Named list. Currently no data is passed to this argument for this
method but that may change in the future.
\(batch, logs = NULL)
Called at the end of a batch in predict()
methods.
Subclasses should override for any actions to run.
Note that if the steps_per_execution
argument to compile
in
Model
is set to N
, this method will only be called every
N
batches.
Args:
batch
: Integer, index of batch within the current epoch.
logs
: Named list. Aggregated metric results up until this batch.
Additional methods or public members of the custom class.
Named list of R objects (typically, functions) to include in
instance private environments. private
methods will have all the same
symbols in scope as public methods (See section "Symbols in Scope"). Each
instance will have it's own private
environment. Any objects
in private
will be invisible from the Keras framework and the Python
runtime.
What the custom class will subclass. By default, the base keras class.
The R environment that all class methods will have as a grandparent.