tf.random.learned_unigram_candidate_sampler
Samples a set of classes from a distribution learned during training.
tf.random.learned_unigram_candidate_sampler(
true_classes, num_true, num_sampled, unique, range_max, seed=None, name=None
)
This operation randomly samples a tensor of sampled classes (sampled_candidates) from the range of integers [0, range_max).
The elements of sampled_candidates are drawn without replacement (if unique=True) or with replacement (if unique=False) from the base distribution.
The base distribution for this operation is constructed on the fly during training. It is a unigram distribution over the target classes seen so far during training. Every integer in [0, range_max) begins with a weight of 1, and is incremented by 1 each time it is seen as a target class. The base distribution is not saved to checkpoints, so it is reset when the model is reloaded.
In addition, this operation returns tensors true_expected_count and sampled_expected_count representing the number of times each of the target classes (true_classes) and the sampled classes (sampled_candidates) is expected to occur in an average tensor of sampled classes. These values correspond to Q(y|x) defined in this document. If unique=True, then these are post-rejection probabilities and we compute them approximately.
| Args | |
|---|---|
true_classes |
A Tensor of type int64 and shape [batch_size, num_true]. The target classes. |
num_true |
An int. The number of target classes per training example. |
num_sampled |
An int. The number of classes to randomly sample. |
unique |
A bool. Determines whether all sampled classes in a batch are unique. |
range_max |
An int. The number of possible classes. |
seed |
An int. An operation-specific seed. Default is 0. |
name |
A name for the operation (optional). |
| Returns | |
|---|---|
sampled_candidates |
A tensor of type int64 and shape [num_sampled]. The sampled classes. |
true_expected_count |
A tensor of type float. Same shape as true_classes. The expected counts under the sampling distribution of each of true_classes. |
sampled_expected_count |
A tensor of type float. Same shape as sampled_candidates. The expected counts under the sampling distribution of each of sampled_candidates. |
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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/random/learned_unigram_candidate_sampler