Basic sampling decoder.
Inherits From: Decoder
tf.contrib.seq2seq.BasicDecoder(
cell, helper, initial_state, output_layer=None
)
Args |
cell
|
An RNNCell instance.
|
helper
|
A Helper instance.
|
initial_state
|
A (possibly nested tuple of...) tensors and TensorArrays.
The initial state of the RNNCell.
|
output_layer
|
(Optional) An instance of tf.compat.v1.layers.Layer , i.e.,
tf.compat.v1.layers.Dense . Optional layer to apply to the RNN output
prior to storing the result or sampling.
|
Raises |
TypeError
|
if cell , helper or output_layer have an incorrect type.
|
Attributes |
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 finished value independently
at each time step. In this case, the dynamic_decode function keeps track
of which batch entries are already finished, and performs a logical OR to
insert new batches to the finished set.
Some decoders, however, shuffle batches / beams between time steps and
dynamic_decode will mix up the finished state across these entries because
it does not track the reshuffle across time steps. In this case, it is
up to the decoder to declare that it will keep track of its own finished
state by setting this property to True .
|
Methods
finalize
View source
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
View source
initialize(
name=None
)
Initialize the decoder.
Args |
name
|
Name scope for any created operations.
|
Returns |
(finished, first_inputs, initial_state) .
|
step
View source
step(
time, inputs, state, name=None
)
Perform a decoding step.
Args |
time
|
scalar int32 tensor.
|
inputs
|
A (structure of) input tensors.
|
state
|
A (structure of) state tensors and TensorArrays.
|
name
|
Name scope for any created operations.
|
Returns |
(outputs, next_state, next_inputs, finished) .
|