Applies natural exponential decay to the initial learning rate.
tf.compat.v1.train.natural_exp_decay( learning_rate, global_step, decay_steps, decay_rate, staircase=False, name=None )
When training a model, it is often recommended to lower the learning rate as the training progresses. This function applies an exponential decay function to a provided initial learning rate. It requires an global_step
value to compute the decayed learning rate. You can just pass a TensorFlow variable that you increment at each training step.
The function returns the decayed learning rate. It is computed as:
decayed_learning_rate = learning_rate * exp(-decay_rate * global_step / decay_step)
or, if staircase
is True
, as:
decayed_learning_rate = learning_rate * exp(-decay_rate * floor(global_step / decay_step))
Example: decay exponentially with a base of 0.96:
... global_step = tf.Variable(0, trainable=False) learning_rate = 0.1 decay_steps = 5 k = 0.5 learning_rate = tf.compat.v1.train.natural_exp_decay(learning_rate, global_step, decay_steps, k) # Passing global_step to minimize() will increment it at each step. learning_step = ( tf.compat.v1.train.GradientDescentOptimizer(learning_rate) .minimize(...my loss..., global_step=global_step) )
Args | |
---|---|
learning_rate | A scalar float32 or float64 Tensor or a Python number. The initial learning rate. |
global_step | A Python number. Global step to use for the decay computation. Must not be negative. |
decay_steps | How often to apply decay. |
decay_rate | A Python number. The decay rate. |
staircase | Whether to apply decay in a discrete staircase, as opposed to continuous, fashion. |
name | String. Optional name of the operation. Defaults to 'ExponentialTimeDecay'. |
Returns | |
---|---|
A scalar Tensor of the same type as learning_rate . The decayed learning rate. |
Raises | |
---|---|
ValueError | if global_step is not supplied. |
When eager execution is enabled, this function returns a function which in turn returns the decayed learning rate Tensor. This can be useful for changing the learning rate value across different invocations of optimizer functions.
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Licensed under the Creative Commons Attribution License 3.0.
Code samples licensed under the Apache 2.0 License.
https://www.tensorflow.org/versions/r2.3/api_docs/python/tf/compat/v1/train/natural_exp_decay