torchrecurrent.AntisymmetricRNN#
- class torchrecurrent.AntisymmetricRNN(input_size, hidden_size, num_layers=1, dropout=0.0, batch_first=False, **kwargs)[source]#
Multi-layer antisymmetric recurrent neural network.
[arXiv]
Each layer consists of an
AntisymmetricRNNCell
, which updates the hidden state according to:\[\begin{split}\begin{array}{ll} \mathbf{A} &= \mathbf{W}_{hh} - \mathbf{W}_{hh}^\top - \gamma \mathbf{I} \\ h_t &= h_{t-1} + \varepsilon \,\tanh(\mathbf{W}_{ih} x_t + \mathbf{b}_{ih} + \mathbf{A} h_{t-1} + \mathbf{b}_{hh}) \end{array}\end{split}\]where \(h_t\) is the hidden state at time t, \(x_t\) is the input at time t, \(\varepsilon\) is a step-size parameter, and \(\gamma \ge 0\) adds diagonal damping for stability. \(\tanh\) is the default nonlinearity (configurable via
nonlinearity
).In a multilayer AntisymmetricRNN, the input \(x^{(l)}_t\) of the \(l\)-th layer (\(l \ge 2\)) is the hidden state \(h^{(l-1)}_t\) of the previous layer multiplied by dropout \(\delta^{(l-1)}_t\), where each \(\delta^{(l-1)}_t\) is a Bernoulli random variable which is 0 with probability
dropout
.- Parameters:
input_size – The number of expected features in the input x.
hidden_size – The number of features in the hidden state h.
num_layers – Number of recurrent layers. E.g., setting
num_layers=2
would mean stacking two antisymmetric RNN layers, with the second receiving the outputs of the first. Default: 1dropout – If non-zero, introduces a Dropout layer on the outputs of each layer except the last layer, with dropout probability equal to
dropout
. Default: 0batch_first – If
True
, then the input and output tensors are provided as (batch, seq, feature) instead of (seq, batch, feature). Default: Falsebias – If
False
, then the layer does not use input-side bias b_ih. Default: Truerecurrent_bias – If
False
, then the layer does not use recurrent bias b_hh. Default: Truenonlinearity – Elementwise nonlinearity applied to the pre-activation. Default:
torch.tanh()
kernel_init – Initializer for weight_ih. Default:
torch.nn.init.xavier_uniform_()
recurrent_kernel_init – Initializer for weight_hh. Default:
torch.nn.init.normal_()
bias_init – Initializer for bias_ih. Default:
torch.nn.init.zeros_()
recurrent_bias_init – Initializer for bias_hh. Default:
torch.nn.init.zeros_()
epsilon – Step-size multiplier \(\varepsilon\). Default: 1.0
gamma – Damping coefficient \(\gamma\) used in the antisymmetric transform. Default: 0.0
device – The desired device of parameters.
dtype – The desired floating point type of parameters.
- Inputs: input, h_0
input: tensor of shape \((L, H_{in})\) for unbatched input, \((L, N, H_{in})\) when
batch_first=False
or \((N, L, H_{in})\) whenbatch_first=True
containing the features of the input sequence. The input can also be a packed variable length sequence. Seetorch.nn.utils.rnn.pack_padded_sequence()
ortorch.nn.utils.rnn.pack_sequence()
for details.h_0: tensor of shape \((\text{num_layers}, H_{out})\) for unbatched input or \((\text{num_layers}, N, H_{out})\) containing the initial hidden state for each element in the input sequence. Defaults to zeros if not provided.
where:
\[\begin{split}\begin{aligned} N ={} & \text{batch size} \\ L ={} & \text{sequence length} \\ H_{in} ={} & \text{input\_size} \\ H_{out} ={} & \text{hidden\_size} \end{aligned}\end{split}\]- Outputs: output, h_n
output: tensor of shape \((L, H_{out})\) for unbatched input, \((L, N, H_{out})\) when
batch_first=False
or \((N, L, H_{out})\) whenbatch_first=True
containing the output features (h_t) from the last layer of the AntisymmetricRNN, for each t. If atorch.nn.utils.rnn.PackedSequence
has been given as the input, the output will also be a packed sequence.h_n: tensor of shape \((\text{num_layers}, H_{out})\) for unbatched input or \((\text{num_layers}, N, H_{out})\) containing the final hidden state for each element in the sequence.
- cells.{k}.weight_ih
the learnable input-hidden weights of the \(k\)-th layer, of shape (hidden_size, input_size) for k = 0. Otherwise, the shape is (hidden_size, hidden_size).
- cells.{k}.weight_hh
the learnable hidden-hidden weights of the \(k\)-th layer, of shape (hidden_size, hidden_size).
- cells.{k}.bias_ih
the learnable input-hidden bias of the \(k\)-th layer, of shape (hidden_size). Only present when
bias=True
.
- cells.{k}.bias_hh
the learnable hidden-hidden bias of the \(k\)-th layer, of shape (hidden_size). Only present when
recurrent_bias=True
.
Note
All the weights and biases are initialized according to the provided initializers (kernel_init, recurrent_kernel_init, etc.).
Note
batch_first
argument is ignored for unbatched inputs.See also
Examples:
>>> rnn = AntisymmetricRNN(10, 20, num_layers=2, dropout=0.1) >>> input = torch.randn(5, 3, 10) # (seq_len, batch, input_size) >>> h0 = torch.randn(2, 3, 20) # (num_layers, batch, hidden_size) >>> output, hn = rnn(input, h0)
- __init__(input_size, hidden_size, num_layers=1, dropout=0.0, batch_first=False, **kwargs)[source]#
Initialize internal Module state, shared by both nn.Module and ScriptModule.
Methods
__init__
(input_size, hidden_size[, ...])Initialize internal Module state, shared by both nn.Module and ScriptModule.
add_module
(name, module)Add a child module to the current module.
apply
(fn)Apply
fn
recursively to every submodule (as returned by.children()
) as well as self.bfloat16
()Casts all floating point parameters and buffers to
bfloat16
datatype.buffers
([recurse])Return an iterator over module buffers.
children
()Return an iterator over immediate children modules.
compile
(*args, **kwargs)Compile this Module's forward using
torch.compile()
.cpu
()Move all model parameters and buffers to the CPU.
cuda
([device])Move all model parameters and buffers to the GPU.
double
()Casts all floating point parameters and buffers to
double
datatype.eval
()Set the module in evaluation mode.
extra_repr
()Return the extra representation of the module.
float
()Casts all floating point parameters and buffers to
float
datatype.forward
(inp[, state])Define the computation performed at every call.
get_buffer
(target)Return the buffer given by
target
if it exists, otherwise throw an error.get_extra_state
()Return any extra state to include in the module's state_dict.
get_parameter
(target)Return the parameter given by
target
if it exists, otherwise throw an error.get_submodule
(target)Return the submodule given by
target
if it exists, otherwise throw an error.half
()Casts all floating point parameters and buffers to
half
datatype.initialize_cells
(cell_class, **kwargs)Helper method to initialize cells for the derived recurrent layer class.
ipu
([device])Move all model parameters and buffers to the IPU.
load_state_dict
(state_dict[, strict, assign])Copy parameters and buffers from
state_dict
into this module and its descendants.modules
()Return an iterator over all modules in the network.
mtia
([device])Move all model parameters and buffers to the MTIA.
named_buffers
([prefix, recurse, ...])Return an iterator over module buffers, yielding both the name of the buffer as well as the buffer itself.
named_children
()Return an iterator over immediate children modules, yielding both the name of the module as well as the module itself.
named_modules
([memo, prefix, remove_duplicate])Return an iterator over all modules in the network, yielding both the name of the module as well as the module itself.
named_parameters
([prefix, recurse, ...])Return an iterator over module parameters, yielding both the name of the parameter as well as the parameter itself.
parameters
([recurse])Return an iterator over module parameters.
register_backward_hook
(hook)Register a backward hook on the module.
register_buffer
(name, tensor[, persistent])Add a buffer to the module.
register_forward_hook
(hook, *[, prepend, ...])Register a forward hook on the module.
register_forward_pre_hook
(hook, *[, ...])Register a forward pre-hook on the module.
register_full_backward_hook
(hook[, prepend])Register a backward hook on the module.
register_full_backward_pre_hook
(hook[, prepend])Register a backward pre-hook on the module.
register_load_state_dict_post_hook
(hook)Register a post-hook to be run after module's
load_state_dict()
is called.register_load_state_dict_pre_hook
(hook)Register a pre-hook to be run before module's
load_state_dict()
is called.register_module
(name, module)Alias for
add_module()
.register_parameter
(name, param)Add a parameter to the module.
register_state_dict_post_hook
(hook)Register a post-hook for the
state_dict()
method.register_state_dict_pre_hook
(hook)Register a pre-hook for the
state_dict()
method.requires_grad_
([requires_grad])Change if autograd should record operations on parameters in this module.
set_extra_state
(state)Set extra state contained in the loaded state_dict.
set_submodule
(target, module[, strict])Set the submodule given by
target
if it exists, otherwise throw an error.share_memory
()See
torch.Tensor.share_memory_()
.state_dict
(*args[, destination, prefix, ...])Return a dictionary containing references to the whole state of the module.
to
(*args, **kwargs)Move and/or cast the parameters and buffers.
to_empty
(*, device[, recurse])Move the parameters and buffers to the specified device without copying storage.
train
([mode])Set the module in training mode.
type
(dst_type)Casts all parameters and buffers to
dst_type
.xpu
([device])Move all model parameters and buffers to the XPU.
zero_grad
([set_to_none])Reset gradients of all model parameters.
Attributes
T_destination
call_super_init
dump_patches
input_size
hidden_size
bias
dropout
batch_first
training