|  TensorFlow 2 version |  View source on GitHub | 
Learning rate scheduler.
Inherits From: Callback
tf.keras.callbacks.LearningRateScheduler(
    schedule, verbose=0
)
| Arguments | |
|---|---|
| schedule | a function that takes an epoch index as input (integer, indexed from 0) and returns a new learning rate as output (float). | 
| verbose | int. 0: quiet, 1: update messages. | 
# This function keeps the learning rate at 0.001 for the first ten epochs
# and decreases it exponentially after that.
def scheduler(epoch):
  if epoch < 10:
    return 0.001
  else:
    return 0.001 * tf.math.exp(0.1 * (10 - epoch))
callback = tf.keras.callbacks.LearningRateScheduler(scheduler)
model.fit(data, labels, epochs=100, callbacks=[callback],
          validation_data=(val_data, val_labels))
Methods
on_batch_begin
on_batch_begin(
    batch, logs=None
)
A backwards compatibility alias for on_train_batch_begin.
on_batch_end
on_batch_end(
    batch, logs=None
)
A backwards compatibility alias for on_train_batch_end.
on_epoch_begin
on_epoch_begin(
    epoch, logs=None
)
Called at the start of an epoch.
Subclasses should override for any actions to run. This function should only be called during TRAIN mode.
| Arguments | |
|---|---|
| epoch | integer, index of epoch. | 
| logs | dict. Currently no data is passed to this argument for this method but that may change in the future. | 
on_epoch_end
on_epoch_end(
    epoch, logs=None
)
Called at the end of an epoch.
Subclasses should override for any actions to run. This function should only be called during TRAIN mode.
| Arguments | |
|---|---|
| epoch | integer, index of epoch. | 
| logs | dict, metric results for this training epoch, and for the
validation epoch if validation is performed. Validation result keys
are prefixed with val_. | 
on_predict_batch_begin
on_predict_batch_begin(
    batch, logs=None
)
Called at the beginning of a batch in predict methods.
Subclasses should override for any actions to run.
| Arguments | |
|---|---|
| batch | integer, index of batch within the current epoch. | 
| logs | dict. Has keys batchandsizerepresenting the current batch
number and the size of the batch. | 
on_predict_batch_end
on_predict_batch_end(
    batch, logs=None
)
Called at the end of a batch in predict methods.
Subclasses should override for any actions to run.
| Arguments | |
|---|---|
| batch | integer, index of batch within the current epoch. | 
| logs | dict. Metric results for this batch. | 
on_predict_begin
on_predict_begin(
    logs=None
)
Called at the beginning of prediction.
Subclasses should override for any actions to run.
| Arguments | |
|---|---|
| logs | dict. Currently no data is passed to this argument for this method but that may change in the future. | 
on_predict_end
on_predict_end(
    logs=None
)
Called at the end of prediction.
Subclasses should override for any actions to run.
| Arguments | |
|---|---|
| logs | dict. Currently no data is passed to this argument for this method but that may change in the future. | 
on_test_batch_begin
on_test_batch_begin(
    batch, logs=None
)
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.
| Arguments | |
|---|---|
| batch | integer, index of batch within the current epoch. | 
| logs | dict. Has keys batchandsizerepresenting the current batch
number and the size of the batch. | 
on_test_batch_end
on_test_batch_end(
    batch, logs=None
)
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.
| Arguments | |
|---|---|
| batch | integer, index of batch within the current epoch. | 
| logs | dict. Metric results for this batch. | 
on_test_begin
on_test_begin(
    logs=None
)
Called at the beginning of evaluation or validation.
Subclasses should override for any actions to run.
| Arguments | |
|---|---|
| logs | dict. Currently no data is passed to this argument for this method but that may change in the future. | 
on_test_end
on_test_end(
    logs=None
)
Called at the end of evaluation or validation.
Subclasses should override for any actions to run.
| Arguments | |
|---|---|
| logs | dict. Currently no data is passed to this argument for this method but that may change in the future. | 
on_train_batch_begin
on_train_batch_begin(
    batch, logs=None
)
Called at the beginning of a training batch in fit methods.
Subclasses should override for any actions to run.
| Arguments | |
|---|---|
| batch | integer, index of batch within the current epoch. | 
| logs | dict. Has keys batchandsizerepresenting the current batch
number and the size of the batch. | 
on_train_batch_end
on_train_batch_end(
    batch, logs=None
)
Called at the end of a training batch in fit methods.
Subclasses should override for any actions to run.
| Arguments | |
|---|---|
| batch | integer, index of batch within the current epoch. | 
| logs | dict. Metric results for this batch. | 
on_train_begin
on_train_begin(
    logs=None
)
Called at the beginning of training.
Subclasses should override for any actions to run.
| Arguments | |
|---|---|
| logs | dict. Currently no data is passed to this argument for this method but that may change in the future. | 
on_train_end
on_train_end(
    logs=None
)
Called at the end of training.
Subclasses should override for any actions to run.
| Arguments | |
|---|---|
| logs | dict. Currently no data is passed to this argument for this method but that may change in the future. | 
set_model
set_model(
    model
)
set_params
set_params(
    params
)