def n_step_gru_base(n_layers, dropout_ratio, hx, ws, bs, xs, use_bi_direction,
**kwargs):
"""n_step_gru_base(n_layers, dropout_ratio, hx, ws, bs, xs, \
use_bi_direction)
Base function for Stack GRU/BiGRU functions.
This function is used at :func:`chainer.functions.n_step_bigru` and
:func:`chainer.functions.n_step_gru`.
This function's behavior depends on argument ``use_bi_direction``.
Args:
n_layers(int): Number of layers.
dropout_ratio(float): Dropout ratio.
hx (:class:`~chainer.Variable`):
Variable holding stacked hidden states.
Its shape is ``(S, B, N)`` where ``S`` is number of layers and is
equal to ``n_layers``, ``B`` is mini-batch size, and ``N`` is
dimension of hidden units. Because of bi-direction, the
first dimension length is ``2S``.
ws (list of list of :class:`~chainer.Variable`): Weight matrices.
``ws[i]`` represents weights for i-th layer.
Each ``ws[i]`` is a list containing six matrices.
``ws[i][j]`` is corresponding with ``W_j`` in the equation.
Only ``ws[0][j]`` where ``0 <= j < 3`` is ``(I, N)`` shape as they
are multiplied with input variables. All other matrices has
``(N, N)`` shape.
bs (list of list of :class:`~chainer.Variable`): Bias vectors.
``bs[i]`` represnents biases for i-th layer.
Each ``bs[i]`` is a list containing six vectors.
``bs[i][j]`` is corresponding with ``b_j`` in the equation.
Shape of each matrix is ``(N,)`` where ``N`` is dimension of
hidden units.
xs (list of :class:`~chainer.Variable`):
A list of :class:`~chainer.Variable` holding input values.
Each element ``xs[t]`` holds input value
for time ``t``. Its shape is ``(B_t, I)``, where ``B_t`` is
mini-batch size for time ``t``, and ``I`` is size of input units.
Note that this function supports variable length sequences.
When sequneces has different lengths, sort sequences in descending
order by length, and transpose the sorted sequence.
:func:`~chainer.functions.transpose_sequence` transpose a list
of :func:`~chainer.Variable` holding sequence.
So ``xs`` needs to satisfy
``xs[t].shape[0] >= xs[t + 1].shape[0]``.
activation (str): Activation function name.
Please select ``tanh`` or ``relu``.
use_bi_direction (bool): If ``True``, this function uses
Bi-direction GRU.
.. seealso::
:func:`chainer.functions.n_step_rnn`
:func:`chainer.functions.n_step_birnn`
"""
if kwargs:
argument.check_unexpected_kwargs(
kwargs,
train='train argument is not supported anymore. '
'Use chainer.using_config',
use_cudnn='use_cudnn argument is not supported anymore. '
'Use chainer.using_config')
argument.assert_kwargs_empty(kwargs)
xp = backend.get_array_module(hx, hx.data)
directions = 1
if use_bi_direction:
directions = 2
combined = _combine_inputs(hx, ws, bs, xs, n_layers, directions)
has_chainerx_array, combined = _extract_apply_in_data(combined)
hx_chx, ws_chx, bs_chx, xs_chx = _seperate_inputs(combined, n_layers,
len(xs), directions)
if has_chainerx_array and xp is chainerx and dropout_ratio == 0:
if use_bi_direction:
hy, ys = chainerx.n_step_bigru(n_layers, hx_chx, ws_chx, bs_chx,
xs_chx)
else:
hy, ys = chainerx.n_step_gru(n_layers, hx_chx, ws_chx, bs_chx,
xs_chx)
hy = variable.Variable._init_unchecked(
hy,
requires_grad=hy.is_backprop_required(),
is_chainerx_array=True)
ys = [
variable.Variable._init_unchecked(
y,
requires_grad=y.is_backprop_required(),
is_chainerx_array=True) for y in ys
]
return hy, ys
if xp is cuda.cupy and chainer.should_use_cudnn('>=auto', 5000):
lengths = [len(x) for x in xs]
xs = chainer.functions.concat(xs, axis=0)
with chainer.using_device(xs.device):
states = cuda.get_cudnn_dropout_states()
states.set_dropout_ratio(dropout_ratio)
w = n_step_rnn.cudnn_rnn_weight_concat(n_layers, states,
use_bi_direction, 'gru', ws, bs)
if use_bi_direction:
rnn = NStepBiGRU
else:
rnn = NStepGRU
hy, ys = rnn(n_layers, states, lengths)(hx, w, xs)
sections = numpy.cumsum(lengths[:-1])
ys = chainer.functions.split_axis(ys, sections, 0)
return hy, ys
else:
hy, _, ys = n_step_rnn.n_step_rnn_impl(_gru, n_layers, dropout_ratio,
hx, None, ws, bs, xs,
use_bi_direction)
return hy, ys
def n_step_lstm_base(
n_layers, dropout_ratio, hx, cx, ws, bs, xs, use_bi_direction,
**kwargs):
"""Base function for Stack LSTM/BiLSTM functions.
This function is used at :func:`chainer.functions.n_step_lstm` and
:func:`chainer.functions.n_step_bilstm`.
This function's behavior depends on following arguments,
``activation`` and ``use_bi_direction``.
Args:
n_layers(int): The number of layers.
dropout_ratio(float): Dropout ratio.
hx (:class:`~chainer.Variable`):
Variable holding stacked hidden states.
Its shape is ``(S, B, N)`` where ``S`` is the number of layers and
is equal to ``n_layers``, ``B`` is the mini-batch size, and ``N``
is the dimension of the hidden units.
cx (:class:`~chainer.Variable`): Variable holding stacked cell states.
It has the same shape as ``hx``.
ws (list of list of :class:`~chainer.Variable`): Weight matrices.
``ws[i]`` represents the weights for the i-th layer.
Each ``ws[i]`` is a list containing eight matrices.
``ws[i][j]`` corresponds to :math:`W_j` in the equation.
Only ``ws[0][j]`` where ``0 <= j < 4`` are ``(N, I)``-shape as they
are multiplied with input variables, where ``I`` is the size of
the input and ``N`` is the dimension of the hidden units. All
other matrices are ``(N, N)``-shaped.
bs (list of list of :class:`~chainer.Variable`): Bias vectors.
``bs[i]`` represents the biases for the i-th layer.
Each ``bs[i]`` is a list containing eight vectors.
``bs[i][j]`` corresponds to :math:`b_j` in the equation.
The shape of each matrix is ``(N,)``.
xs (list of :class:`~chainer.Variable`):
A list of :class:`~chainer.Variable`
holding input values. Each element ``xs[t]`` holds input value
for time ``t``. Its shape is ``(B_t, I)``, where ``B_t`` is the
mini-batch size for time ``t``. The sequences must be transposed.
:func:`~chainer.functions.transpose_sequence` can be used to
transpose a list of :class:`~chainer.Variable`\\ s each
representing a sequence.
When sequences has different lengths, they must be
sorted in descending order of their lengths before transposing.
So ``xs`` needs to satisfy
``xs[t].shape[0] >= xs[t + 1].shape[0]``.
use_bi_direction (bool): If ``True``, this function uses Bi-directional
LSTM.
Returns:
tuple: This function returns a tuple containing three elements,
``hy``, ``cy`` and ``ys``.
- ``hy`` is an updated hidden states whose shape is the same as
``hx``.
- ``cy`` is an updated cell states whose shape is the same as
``cx``.
- ``ys`` is a list of :class:`~chainer.Variable` . Each element
``ys[t]`` holds hidden states of the last layer corresponding
to an input ``xs[t]``. Its shape is ``(B_t, N)`` where ``B_t`` is
the mini-batch size for time ``t``. Note that ``B_t`` is the same
value as ``xs[t]``.
.. seealso::
:func:`chainer.functions.n_step_lstm`
:func:`chainer.functions.n_step_bilstm`
"""
if kwargs:
argument.check_unexpected_kwargs(
kwargs, train='train argument is not supported anymore. '
'Use chainer.using_config',
use_cudnn='use_cudnn argument is not supported anymore. '
'Use chainer.using_config')
argument.assert_kwargs_empty(kwargs)
# Check input size consistency with xs and ws here.
x_in = xs[0].shape[1]
w_in = ws[0][0].shape[1]
if x_in != w_in:
raise ValueError('Inconsistent input size in input values and weight '
'parameters: {} != {}'.format(x_in, w_in))
xp = backend.get_array_module(hx, hx.data)
use_cuda = xp is cuda.cupy or (
xp is chainerx and hx.device.device.backend.name == 'cuda')
directions = 1
if use_bi_direction:
directions = 2
combined = _combine_inputs(hx, cx, ws, bs, xs, n_layers, directions)
has_chainerx_array, combined = _extract_apply_in_data(combined)
hx_chx, cx_chx, ws_chx, bs_chx, xs_chx = _seperate_inputs(
combined, n_layers, len(xs), directions)
if has_chainerx_array and xp is chainerx and dropout_ratio == 0:
if use_bi_direction:
hy, cy, ys = chainerx.n_step_bilstm(
n_layers, hx_chx, cx_chx, ws_chx, bs_chx, xs_chx)
else:
hy, cy, ys = chainerx.n_step_lstm(
n_layers, hx_chx, cx_chx, ws_chx, bs_chx, xs_chx)
hy = variable.Variable._init_unchecked(
hy, requires_grad=hy.is_backprop_required(),
is_chainerx_array=True)
cy = variable.Variable._init_unchecked(
cy, requires_grad=cy.is_backprop_required(),
is_chainerx_array=True)
ys = [variable.Variable._init_unchecked(
y, requires_grad=y.is_backprop_required(),
is_chainerx_array=True)
for y in ys]
return hy, cy, ys
elif use_cuda and chainer.should_use_cudnn('>=auto', 5000):
lengths = [len(x) for x in xs]
xs = chainer.functions.concat(xs, axis=0)
with chainer.using_device(xs.device):
states = cuda.get_cudnn_dropout_states()
states.set_dropout_ratio(dropout_ratio)
w = n_step_rnn.cudnn_rnn_weight_concat(
n_layers, states, use_bi_direction, 'lstm', ws, bs)
if use_bi_direction:
rnn = NStepBiLSTM
else:
rnn = NStepLSTM
hy, cy, ys = rnn(n_layers, states, lengths)(hx, cx, w, xs)
sections = numpy.cumsum(lengths[:-1])
ys = chainer.functions.split_axis(ys, sections, 0)
return hy, cy, ys
else:
return n_step_rnn.n_step_rnn_impl(
_lstm, n_layers, dropout_ratio, hx, cx, ws, bs, xs,
use_bi_direction)