public TensorArray scatter(Tensor indices, Tensor value, string name = null)
{
return(tf_with(ops.name_scope(name, "TensorArrayScatter", new { _handle, value, indices }), delegate
{
value = ops.convert_to_tensor(value, preferred_dtype: _dtype, name: "value");
if (_infer_shape)
{
var shape = new TensorShape(value.TensorShape.dims.Skip(1).ToArray());
_merge_element_shape(shape);
}
_maybe_colocate_with(value);
var flow_out = gen_data_flow_ops.tensor_array_scatter_v3(
handle: _handle,
indices: indices,
value: value,
flow_in: _flow,
name: name);
var ta = new TensorArray(_dtype,
infer_shape: _infer_shape,
element_shape: _element_shape[0],
dynamic_size: _dynamic_size,
handle: _handle,
flow: flow_out,
colocate_with_first_write_call: _colocate_with_first_write_call);
return ta;
}));
}
/// <summary>
/// Internal implementation of Dynamic RNN.
/// </summary>
/// <param name="cell"></param>
/// <param name="inputs"></param>
/// <param name="initial_state"></param>
/// <param name="parallel_iterations"></param>
/// <param name="swap_memory"></param>
/// <param name="sequence_length"></param>
/// <param name="dtype"></param>
/// <returns></returns>
private static (Tensor, Tensor) _dynamic_rnn_loop(RnnCell cell, Tensor inputs, Tensor initial_state,
int parallel_iterations, bool swap_memory, Tensor sequence_length = null, TF_DataType dtype = TF_DataType.DtInvalid)
{
var state = initial_state;
var state_size = cell.state_size;
var flat_input = nest.flatten(inputs);
var flat_output_size = nest.flatten(cell.output_size);
// Construct an initial output
var input_shape = array_ops.shape(flat_input[0]);
var time_steps = input_shape.slice(0);
var batch_size = _best_effort_input_batch_size(flat_input);
var inputs_got_shape = flat_input.Select(input_ => input_.TensorShape.with_rank_at_least(3)).ToArray();
var dims = inputs_got_shape[0].dims.Take(2).ToArray();
var(const_time_steps, const_batch_size) = (dims[0], dims[1]);
foreach (var shape in inputs_got_shape)
{
if (shape.dims[2] == -1)
{
throw new ValueError("Input size (depth of inputs) must be accessible via shape inference," +
" but saw value None.");
}
var got_time_steps = shape.dims[0];
var got_batch_size = shape.dims[1];
if (const_time_steps != got_time_steps)
{
throw new ValueError("Time steps is not the same for all the elements in the input in a " +
"batch.");
}
if (const_batch_size != got_batch_size)
{
throw new ValueError("Batch_size is not the same for all the elements in the input.");
}
}
Func <int, Tensor> _create_zero_arrays = (size_) =>
{
var size = rnn_cell_impl._concat(batch_size, size_);
return(array_ops.zeros(
array_ops.stack(size), dtype: _infer_state_dtype(dtype, state)));
};
// Prepare dynamic conditional copying of state & output
var flat_zero_output = flat_output_size.Select(output => _create_zero_arrays(output)).ToArray();
var zero_output = nest.pack_sequence_as(structure: cell.output_size, flat_sequence: flat_zero_output);
Tensor min_sequence_length = null, max_sequence_length = null;
if (sequence_length != null)
{
min_sequence_length = math_ops.reduce_min(sequence_length);
max_sequence_length = math_ops.reduce_max(sequence_length);
}
else
{
max_sequence_length = time_steps;
}
var time = array_ops.constant(0, dtype: dtypes.int32, name: "time");
string base_name = null;
tf_with(ops.name_scope("dynamic_rnn"), scope => base_name = scope);
Func <string, TensorShape, TF_DataType, TensorArray> _create_ta = (name, element_shape, dtype_) =>
{
var ta = new TensorArray(dtype: dtype_,
size: time_steps,
element_shape: element_shape,
tensor_array_name: base_name + name);
return(ta);
};
bool in_graph_mode = true;
var output_ta = new List <TensorArray>();
var input_ta = new List <TensorArray>();
if (in_graph_mode)
{
foreach (var(i, out_size) in enumerate(flat_output_size))
{
output_ta.Add(_create_ta($"output_{i}",
new TensorShape(const_batch_size).concatenate(
_maybe_tensor_shape_from_tensor(out_size)),
_infer_state_dtype(dtype, state)));
}
foreach (var(i, flat_input_i) in enumerate(flat_input))
{
input_ta.Add(_create_ta($"input_{i}",
new TensorShape(flat_input_i.dims.Skip(1).ToArray()),
flat_input_i.dtype));
}
input_ta = zip(input_ta, flat_input).Select(x =>
{
var(ta, input_) = (x.Item1, x.Item2);
return(ta.unstack(input_));
}).ToList();
}
// Make sure that we run at least 1 step, if necessary, to ensure
// the TensorArrays pick up the dynamic shape.
Tensor loop_bound = null;
if (in_graph_mode)
{
loop_bound = math_ops.minimum(
time_steps, math_ops.maximum(1, max_sequence_length));
}
Func <BodyItemInRnnWhileLoop, Tensor> cond = (item) =>
{
return(item.time < loop_bound);
};
// Take a time step of the dynamic RNN.
Func <BodyItemInRnnWhileLoop, BodyItemInRnnWhileLoop> _time_step = (item) =>
{
Tensor[] input_t = null;
var(time1, output_ta_t, state1) = (item.time, item.output_ta_t, item.state);
if (in_graph_mode)
{
input_t = input_ta.Select(ta => ta.read(time1)).ToArray();
// Restore some shape information
foreach (var(input_, shape) in zip(input_t, inputs_got_shape))
{
input_.set_shape(shape[new Slice(1)]);
}
}
else
{
// input_t = tuple(ta[time.numpy()] for ta in input_ta)
}
var input_t_t = nest.pack_sequence_as2(structure: inputs, flat_sequence: input_t);
// Keras RNN cells only accept state as list, even if it's a single tensor.
// var is_keras_rnn_cell = _is_keras_rnn_cell(cell);
Tensor[] outputs = null;
if (sequence_length != null)
{
throw new NotImplementedException("sequence_length != null");
}
else
{
outputs = cell.__call__(input_t_t, state: state1);
}
var(output, new_state) = (outputs[0], outputs[1]);
// Keras cells always wrap state as list, even if it's a single tensor.
// if(is_keras_rnn_cell && len(new_state)) == 1
// Pack state if using state tuples
outputs = nest.flatten2(output).Select(x => x as Tensor).ToArray();
output_ta_t = zip(output_ta_t, outputs).Select(x =>
{
var(ta, @out) = (x.Item1, x.Item2);
return(ta.write(item.time, @out));
}).ToArray();
return(new BodyItemInRnnWhileLoop(item.time + 1, output_ta_t, new_state));
};
/// <summary>
/// Internal implementation of Dynamic RNN.
/// </summary>
/// <param name="cell"></param>
/// <param name="inputs"></param>
/// <param name="initial_state"></param>
/// <param name="parallel_iterations"></param>
/// <param name="swap_memory"></param>
/// <param name="sequence_length"></param>
/// <param name="dtype"></param>
/// <returns></returns>
private static (Tensor, Tensor) _dynamic_rnn_loop(RNNCell cell, Tensor inputs, Tensor initial_state,
int parallel_iterations, bool swap_memory, Tensor sequence_length = null, TF_DataType dtype = TF_DataType.DtInvalid)
{
var state = initial_state;
var state_size = cell.state_size;
var flat_input = nest.flatten(inputs);
var flat_output_size = nest.flatten(cell.output_size);
// Construct an initial output
var input_shape = array_ops.shape(flat_input[0]);
var time_steps = input_shape.slice(0);
var batch_size = _best_effort_input_batch_size(flat_input);
var inputs_got_shape = flat_input.Select(input_ => input_.TensorShape.with_rank_at_least(3)).ToArray();
var dims = inputs_got_shape[0].dims.Take(2).ToArray();
var(const_time_steps, const_batch_size) = (dims[0], dims[1]);
foreach (var shape in inputs_got_shape)
{
if (shape.dims[2] == -1)
{
throw new ValueError("Input size (depth of inputs) must be accessible via shape inference," +
" but saw value None.");
}
var got_time_steps = shape.dims[0];
var got_batch_size = shape.dims[1];
if (const_time_steps != got_time_steps)
{
throw new ValueError("Time steps is not the same for all the elements in the input in a " +
"batch.");
}
if (const_batch_size != got_batch_size)
{
throw new ValueError("Batch_size is not the same for all the elements in the input.");
}
}
Func <int, Tensor> _create_zero_arrays = (size_) =>
{
var size = rnn_cell_impl._concat(batch_size, size_);
return(array_ops.zeros(
array_ops.stack(size), dtype: _infer_state_dtype(dtype, state)));
};
// Prepare dynamic conditional copying of state & output
var flat_zero_output = flat_output_size.Select(output => _create_zero_arrays(output)).ToArray();
var zero_output = nest.pack_sequence_as(structure: cell.output_size, flat_sequence: flat_zero_output);
Tensor min_sequence_length = null, max_sequence_length = null;
if (sequence_length != null)
{
min_sequence_length = math_ops.reduce_min(sequence_length);
max_sequence_length = math_ops.reduce_max(sequence_length);
}
else
{
max_sequence_length = time_steps;
}
var time = array_ops.constant(0, dtype: dtypes.int32, name: "time");
string base_name = null;
tf_with(ops.name_scope("dynamic_rnn"), scope => base_name = scope);
Func <string, TensorShape, TF_DataType, TensorArray> _create_ta = (name, element_shape, dtype_) =>
{
var ta = new TensorArray(dtype: dtype_,
size: time_steps,
element_shape: new[] { element_shape },
tensor_array_name: base_name + name);
return(ta);
};
bool in_graph_mode = true;
var output_ta = new List <TensorArray>();
var input_ta = new List <TensorArray>();
if (in_graph_mode)
{
foreach (var(i, out_size) in enumerate(flat_output_size))
{
output_ta.Add(_create_ta($"output_{i}",
new TensorShape(const_batch_size).concatenate(
_maybe_tensor_shape_from_tensor(out_size)),
_infer_state_dtype(dtype, state)));
}
foreach (var(i, flat_input_i) in enumerate(flat_input))
{
input_ta.Add(_create_ta($"input_{i}",
new TensorShape(flat_input_i.dims.Skip(1).ToArray()),
flat_input_i.dtype));
}
for (int i = 0; i < input_ta.Count; i++)
{
var(ta, input_) = (input_ta[0], flat_input[0]);
}
}
// Make sure that we run at least 1 step, if necessary, to ensure
// the TensorArrays pick up the dynamic shape.
Tensor loop_bound;
if (in_graph_mode)
{
loop_bound = math_ops.minimum(
time_steps, math_ops.maximum(1, max_sequence_length));
}
/*Func<Tensor, Tensor> cond = (ctime) =>
* {
* return null;
* };
*
* control_flow_ops.while_loop(
* cond: cond,
* body = );*/
throw new NotImplementedException("");
}
