tfa.seq2seq.InferenceSampler

An inference sampler that uses a custom sampling function.

Inherits From: Sampler

tfa.seq2seq.InferenceSampler(
    sample_fn: Callable,
    sample_shape: tfa.types.TensorLike,
    sample_dtype: tfa.types.AcceptableDTypes,
    end_fn: Callable,
    next_inputs_fn: Optional[Callable] = None
)

sample_fn A callable that takes outputs and emits tensor sample_ids.
sample_shape Either a list of integers, or a 1-D Tensor of type int32, the shape of the each sample in the batch returned by sample_fn.
sample_dtype the dtype of the sample returned by sample_fn.
end_fn A callable that takes sample_ids and emits a bool vector shaped [batch_size] indicating whether each sample is an end token.
next_inputs_fn (Optional) A callable that takes sample_ids and returns the next batch of inputs. If not provided, sample_ids is used as the next batch of inputs.

batch_size Batch size of tensor returned by sample.

Returns a scalar int32 tensor. The return value might not available before the invocation of initialize(), in this case, ValueError is raised.

sample_ids_dtype DType of tensor returned by sample.

Returns a DType. The return value might not available before the invocation of initialize().

sample_ids_shape Shape of tensor returned by sample, excluding the batch dimension.

Returns a TensorShape. The return value might not available before the invocation of initialize().

Methods

initialize

View source

initialize(
    start_inputs
)

initialize the sampler with the input tensors.

This method must be invoked exactly once before calling other methods of the Sampler.

Args
inputs A (structure of) input tensors, it could be a nested tuple or a single tensor.
**kwargs Other kwargs for initialization. It could contain tensors like mask for inputs, or non tensor parameter.

Returns
(initial_finished, initial_inputs).

next_inputs

View source

next_inputs(
    time, outputs, state, sample_ids
)

Returns (finished, next_inputs, next_state).

sample

View source

sample(
    time, outputs, state
)

Returns sample_ids.