tf.contrib.seq2seq.Decoder
An RNN Decoder abstract interface object.
Concepts used by this interface:
-
inputs
: (structure of) tensors and TensorArrays that is passed as input to the RNNCell composing the decoder, at each time step. -
state
: (structure of) tensors and TensorArrays that is passed to the RNNCell instance as the state. -
finished
: boolean tensor telling whether each sequence in the batch is finished. -
outputs
: Instance of BasicDecoderOutput. Result of the decoding, at each time step.
Attributes | |
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batch_size |
The batch size of input values. |
output_dtype |
A (possibly nested tuple of...) dtype[s]. |
output_size |
A (possibly nested tuple of...) integer[s] or TensorShape object[s]. |
tracks_own_finished |
Describes whether the Decoder keeps track of finished states. Most decoders will emit a true/false Some decoders, however, shuffle batches / beams between time steps and |
Methods
finalize
finalize( outputs, final_state, sequence_lengths )
Called after decoding iterations complete.
Args | |
---|---|
outputs |
RNNCell outputs (possibly nested tuple of) tensor[s] for all time steps. |
final_state |
RNNCell final state (possibly nested tuple of) tensor[s] for last time step. |
sequence_lengths |
1-D int32 tensor containing lengths of each sequence. |
Returns | |
---|---|
(final_outputs, final_state) : final_outputs is an object containing the final decoder output, final_state is a (structure of) state tensors and TensorArrays. |
initialize
@abc.abstractmethod initialize( name=None )
Called before any decoding iterations.
This methods must compute initial input values and initial state.
Args | |
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name |
Name scope for any created operations. |
Returns | |
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(finished, initial_inputs, initial_state) : initial values of 'finished' flags, inputs and state. |
step
@abc.abstractmethod step( time, inputs, state, name=None )
Called per step of decoding (but only once for dynamic decoding).
Args | |
---|---|
time |
Scalar int32 tensor. Current step number. |
inputs |
RNNCell input (possibly nested tuple of) tensor[s] for this time step. |
state |
RNNCell state (possibly nested tuple of) tensor[s] from previous time step. |
name |
Name scope for any created operations. |
Returns | |
---|---|
(outputs, next_state, next_inputs, finished) : outputs is an object containing the decoder output, next_state is a (structure of) state tensors and TensorArrays, next_inputs is the tensor that should be used as input for the next step, finished is a boolean tensor telling whether the sequence is complete, for each sequence in the batch. |
© 2020 The TensorFlow Authors. All rights reserved.
Licensed under the Creative Commons Attribution License 3.0.
Code samples licensed under the Apache 2.0 License.
https://www.tensorflow.org/versions/r1.15/api_docs/python/tf/contrib/seq2seq/Decoder