pantheonrl.common.util.FeedForward32Policy

class FeedForward32Policy(*args, **kwargs)[source]

Bases: ActorCriticPolicy

A feed forward policy network with two hidden layers of 32 units. This matches the IRL policies in the original AIRL paper. Note: This differs from stable_baselines3 ActorCriticPolicy in two ways: by having 32 rather than 64 units, and by having policy and value networks share weights except at the final layer.

Initializes internal Module state, shared by both nn.Module and ScriptModule.

Methods

`add_module`	Adds a child module to the current module.
`apply`	Applies `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`	Returns an iterator over module buffers.
`children`	Returns an iterator over immediate children modules.
`cpu`	Moves all model parameters and buffers to the CPU.
`cuda`	Moves all model parameters and buffers to the GPU.
`double`	Casts all floating point parameters and buffers to `double` datatype.
`eval`	Sets the module in evaluation mode.
`evaluate_actions`	Evaluate actions according to the current policy, given the observations.
`extra_repr`	Set the extra representation of the module
`extract_features`	Preprocess the observation if needed and extract features.
`float`	Casts all floating point parameters and buffers to `float` datatype.
`forward`	Forward pass in all the networks (actor and critic)
`get_buffer`	Returns the buffer given by `target` if it exists, otherwise throws an error.
`get_distribution`	Get the current policy distribution given the observations.
`get_extra_state`	Returns any extra state to include in the module's state_dict.
`get_parameter`	Returns the parameter given by `target` if it exists, otherwise throws an error.
`get_submodule`	Returns the submodule given by `target` if it exists, otherwise throws an error.
`half`	Casts all floating point parameters and buffers to `half` datatype.
`init_weights`	Orthogonal initialization (used in PPO and A2C)
`ipu`	Moves all model parameters and buffers to the IPU.
`is_vectorized_observation`	Check whether or not the observation is vectorized, apply transposition to image (so that they are channel-first) if needed.
`load`	Load model from path.
`load_from_vector`	Load parameters from a 1D vector.
`load_state_dict`	Copies parameters and buffers from `state_dict` into this module and its descendants.
`make_features_extractor`	Helper method to create a features extractor.
`modules`	Returns an iterator over all modules in the network.
`named_buffers`	Returns an iterator over module buffers, yielding both the name of the buffer as well as the buffer itself.
`named_children`	Returns an iterator over immediate children modules, yielding both the name of the module as well as the module itself.
`named_modules`	Returns an iterator over all modules in the network, yielding both the name of the module as well as the module itself.
`named_parameters`	Returns an iterator over module parameters, yielding both the name of the parameter as well as the parameter itself.
`obs_to_tensor`	Convert an input observation to a PyTorch tensor that can be fed to a model.
`parameters`	Returns an iterator over module parameters.
`parameters_to_vector`	Convert the parameters to a 1D vector.
`predict`	Get the policy action from an observation (and optional hidden state).
`predict_values`	Get the estimated values according to the current policy given the observations.
`register_backward_hook`	Registers a backward hook on the module.
`register_buffer`	Adds a buffer to the module.
`register_forward_hook`	Registers a forward hook on the module.
`register_forward_pre_hook`	Registers a forward pre-hook on the module.
`register_full_backward_hook`	Registers a backward hook on the module.
`register_full_backward_pre_hook`	Registers a backward pre-hook on the module.
`register_load_state_dict_post_hook`	Registers a post hook to be run after module's `load_state_dict` is called.
`register_module`	Alias for `add_module()`.
`register_parameter`	Adds a parameter to the module.
`register_state_dict_pre_hook`	These hooks will be called with arguments: `self`, `prefix`, and `keep_vars` before calling `state_dict` on `self`.
`requires_grad_`	Change if autograd should record operations on parameters in this module.
`reset_noise`	Sample new weights for the exploration matrix.
`save`	Save model to a given location.
`scale_action`	Rescale the action from [low, high] to [-1, 1] (no need for symmetric action space)
`set_extra_state`	This function is called from `load_state_dict()` to handle any extra state found within the state_dict.
`set_training_mode`	Put the policy in either training or evaluation mode.
`share_memory`	See `torch.Tensor.share_memory_()`
`state_dict`	Returns a dictionary containing references to the whole state of the module.
`to`	Moves and/or casts the parameters and buffers.
`to_empty`	Moves the parameters and buffers to the specified device without copying storage.
`train`	Sets the module in training mode.
`type`	Casts all parameters and buffers to `dst_type`.
`unscale_action`	Rescale the action from [-1, 1] to [low, high] (no need for symmetric action space)
`xpu`	Moves all model parameters and buffers to the XPU.
`zero_grad`	Sets gradients of all model parameters to zero.

Attributes

`T_destination`
`call_super_init`
`device`	Infer which device this policy lives on by inspecting its parameters.
`dump_patches`
`squash_output`	(bool) Getter for squash_output.
`features_extractor`
`optimizer`
`training`

__call__(*args, **kwargs): Call self as a function.

add_module(name, module)

Adds a child module to the current module.

The module can be accessed as an attribute using the given name.

Args:

name (str): name of the child module. The child module can be: accessed from this module using the given name

module (Module): child module to be added to the module.

Parameters:

name (str) –
module (Module | None) –

Return type:

None

apply(fn)

Applies fn recursively to every submodule (as returned by .children()) as well as self. Typical use includes initializing the parameters of a model (see also nn-init-doc).

Args:: fn (Module -> None): function to be applied to each submodule
Returns:: Module: self

Example:

>>> @torch.no_grad()
>>> def init_weights(m):
>>>     print(m)
>>>     if type(m) == nn.Linear:
>>>         m.weight.fill_(1.0)
>>>         print(m.weight)
>>> net = nn.Sequential(nn.Linear(2, 2), nn.Linear(2, 2))
>>> net.apply(init_weights)
Linear(in_features=2, out_features=2, bias=True)
Parameter containing:
tensor([[1., 1.],
        [1., 1.]], requires_grad=True)
Linear(in_features=2, out_features=2, bias=True)
Parameter containing:
tensor([[1., 1.],
        [1., 1.]], requires_grad=True)
Sequential(
  (0): Linear(in_features=2, out_features=2, bias=True)
  (1): Linear(in_features=2, out_features=2, bias=True)
)

Parameters:

self (T) –
fn (Callable[[Module], None]) –

Return type:

T

bfloat16()

Casts all floating point parameters and buffers to bfloat16 datatype.

Note

This method modifies the module in-place.

Returns:: Module: self

Parameters:: self (T) –
Return type:: T

buffers(recurse=True)

Returns an iterator over module buffers.

Args:

recurse (bool): if True, then yields buffers of this module: and all submodules. Otherwise, yields only buffers that are direct members of this module.

Yields:

torch.Tensor: module buffer

Example:

>>> # xdoctest: +SKIP("undefined vars")
>>> for buf in model.buffers():
>>>     print(type(buf), buf.size())
<class 'torch.Tensor'> (20L,)
<class 'torch.Tensor'> (20L, 1L, 5L, 5L)

Parameters:: recurse (bool) –
Return type:: Iterator[Tensor]

children()

Returns an iterator over immediate children modules.

Yields:: Module: a child module

Return type:: Iterator[Module]

cpu()

Moves all model parameters and buffers to the CPU.

Note

This method modifies the module in-place.

Returns:: Module: self

Parameters:: self (T) –
Return type:: T

cuda(device=None)

Moves all model parameters and buffers to the GPU.

This also makes associated parameters and buffers different objects. So it should be called before constructing optimizer if the module will live on GPU while being optimized.

Note

This method modifies the module in-place.

Args:

device (int, optional): if specified, all parameters will be: copied to that device

Returns:

Module: self

Parameters:

self (T) –
device (int | device | None) –

Return type:

T

property device: device

Infer which device this policy lives on by inspecting its parameters. If it has no parameters, the ‘cpu’ device is used as a fallback.

Returns:

double()

Casts all floating point parameters and buffers to double datatype.

Note

This method modifies the module in-place.

Returns:: Module: self

Parameters:: self (T) –
Return type:: T

eval()

Sets the module in evaluation mode.

This has any effect only on certain modules. See documentations of particular modules for details of their behaviors in training/evaluation mode, if they are affected, e.g. Dropout, BatchNorm, etc.

This is equivalent with self.train(False).

See locally-disable-grad-doc for a comparison between .eval() and several similar mechanisms that may be confused with it.

Returns:: Module: self

Parameters:: self (T) –
Return type:: T

evaluate_actions(obs, actions)

Evaluate actions according to the current policy, given the observations.

Parameters:

obs (Tensor) – Observation
actions (Tensor) – Actions

Returns:

estimated value, log likelihood of taking those actions and entropy of the action distribution.

Return type:

Tuple[Tensor, Tensor, Tensor | None]

extra_repr()

Set the extra representation of the module

To print customized extra information, you should re-implement this method in your own modules. Both single-line and multi-line strings are acceptable.

Return type:: str

extract_features(obs)

Preprocess the observation if needed and extract features.

Parameters:: obs (Tensor) – Observation
Returns:: the output of the features extractor(s)
Return type:: Tensor | Tuple[Tensor, Tensor]

float()

Casts all floating point parameters and buffers to float datatype.

Note

This method modifies the module in-place.

Returns:: Module: self

Parameters:: self (T) –
Return type:: T

forward(obs, deterministic=False)

Forward pass in all the networks (actor and critic)

Parameters:

obs (Tensor) – Observation
deterministic (bool) – Whether to sample or use deterministic actions

Returns:

action, value and log probability of the action

Return type:

Tuple[Tensor, Tensor, Tensor]

get_buffer(target)

Returns the buffer given by target if it exists, otherwise throws an error.

See the docstring for get_submodule for a more detailed explanation of this method’s functionality as well as how to correctly specify target.

Args:

target: The fully-qualified string name of the buffer: to look for. (See get_submodule for how to specify a fully-qualified string.)

Returns:

torch.Tensor: The buffer referenced by target

Raises:

AttributeError: If the target string references an invalid: path or resolves to something that is not a buffer

Parameters:: target (str) –
Return type:: Tensor

get_distribution(obs)

Get the current policy distribution given the observations.

Parameters:: obs (Tensor) –
Returns:: the action distribution.
Return type:: Distribution

get_extra_state()

Returns any extra state to include in the module’s state_dict. Implement this and a corresponding set_extra_state() for your module if you need to store extra state. This function is called when building the module’s state_dict().

Note that extra state should be picklable to ensure working serialization of the state_dict. We only provide provide backwards compatibility guarantees for serializing Tensors; other objects may break backwards compatibility if their serialized pickled form changes.

Returns:: object: Any extra state to store in the module’s state_dict

Return type:: Any

get_parameter(target)

Returns the parameter given by target if it exists, otherwise throws an error.

See the docstring for get_submodule for a more detailed explanation of this method’s functionality as well as how to correctly specify target.

Args:

target: The fully-qualified string name of the Parameter: to look for. (See get_submodule for how to specify a fully-qualified string.)

Returns:

torch.nn.Parameter: The Parameter referenced by target

Raises:

AttributeError: If the target string references an invalid: path or resolves to something that is not an nn.Parameter

Parameters:: target (str) –
Return type:: Parameter

get_submodule(target)

Returns the submodule given by target if it exists, otherwise throws an error.

For example, let’s say you have an nn.Module A that looks like this:

A(
    (net_b): Module(
        (net_c): Module(
            (conv): Conv2d(16, 33, kernel_size=(3, 3), stride=(2, 2))
        )
        (linear): Linear(in_features=100, out_features=200, bias=True)
    )
)

(The diagram shows an nn.Module A. A has a nested submodule net_b, which itself has two submodules net_c and linear. net_c then has a submodule conv.)

To check whether or not we have the linear submodule, we would call get_submodule("net_b.linear"). To check whether we have the conv submodule, we would call get_submodule("net_b.net_c.conv").

The runtime of get_submodule is bounded by the degree of module nesting in target. A query against named_modules achieves the same result, but it is O(N) in the number of transitive modules. So, for a simple check to see if some submodule exists, get_submodule should always be used.

Args:

target: The fully-qualified string name of the submodule: to look for. (See above example for how to specify a fully-qualified string.)

Returns:

torch.nn.Module: The submodule referenced by target

Raises:

AttributeError: If the target string references an invalid: path or resolves to something that is not an nn.Module

Parameters:: target (str) –
Return type:: Module

half()

Casts all floating point parameters and buffers to half datatype.

Note

This method modifies the module in-place.

Returns:: Module: self

Parameters:: self (T) –
Return type:: T

static init_weights(module, gain=1)

Orthogonal initialization (used in PPO and A2C)

Parameters:

module (Module) –
gain (float) –

Return type:

None

ipu(device=None)

Moves all model parameters and buffers to the IPU.

This also makes associated parameters and buffers different objects. So it should be called before constructing optimizer if the module will live on IPU while being optimized.

Note

This method modifies the module in-place.

Arguments:

device (int, optional): if specified, all parameters will be: copied to that device

Returns:

Module: self

Parameters:

self (T) –
device (int | device | None) –

Return type:

T

is_vectorized_observation(observation)

Check whether or not the observation is vectorized, apply transposition to image (so that they are channel-first) if needed. This is used in DQN when sampling random action (epsilon-greedy policy)

Parameters:: observation (ndarray | Dict[str, ndarray]) – the input observation to check
Returns:: whether the given observation is vectorized or not
Return type:: bool

classmethod load(path, device='auto')

Load model from path.

Parameters:

path (str) –
device (device | str) – Device on which the policy should be loaded.

Returns:

Return type:

SelfBaseModel

load_from_vector(vector)

Load parameters from a 1D vector.

Parameters:: vector (ndarray) –
Return type:: None

load_state_dict(state_dict, strict=True)

Copies parameters and buffers from state_dict into this module and its descendants. If strict is True, then the keys of state_dict must exactly match the keys returned by this module’s state_dict() function.

Args:

state_dict (dict): a dict containing parameters and: persistent buffers.
strict (bool, optional): whether to strictly enforce that the keys: in state_dict match the keys returned by this module’s state_dict() function. Default: True

Returns:

NamedTuple with missing_keys and unexpected_keys fields:

missing_keys is a list of str containing the missing keys
unexpected_keys is a list of str containing the unexpected keys

Note:

If a parameter or buffer is registered as None and its corresponding key exists in state_dict, load_state_dict() will raise a RuntimeError.

Parameters:

state_dict (Mapping[str, Any]) –
strict (bool) –

make_features_extractor()

Helper method to create a features extractor.

Return type:: BaseFeaturesExtractor

modules()

Returns an iterator over all modules in the network.

Yields:: Module: a module in the network
Note:: Duplicate modules are returned only once. In the following example, l will be returned only once.

Example:

>>> l = nn.Linear(2, 2)
>>> net = nn.Sequential(l, l)
>>> for idx, m in enumerate(net.modules()):
...     print(idx, '->', m)

0 -> Sequential(
  (0): Linear(in_features=2, out_features=2, bias=True)
  (1): Linear(in_features=2, out_features=2, bias=True)
)
1 -> Linear(in_features=2, out_features=2, bias=True)

Return type:: Iterator[Module]

named_buffers(prefix='', recurse=True, remove_duplicate=True)

Returns an iterator over module buffers, yielding both the name of the buffer as well as the buffer itself.

Args:

prefix (str): prefix to prepend to all buffer names. recurse (bool, optional): if True, then yields buffers of this module

and all submodules. Otherwise, yields only buffers that are direct members of this module. Defaults to True.

remove_duplicate (bool, optional): whether to remove the duplicated buffers in the result. Defaults to True.

Yields:

(str, torch.Tensor): Tuple containing the name and buffer

Example:

>>> # xdoctest: +SKIP("undefined vars")
>>> for name, buf in self.named_buffers():
>>>     if name in ['running_var']:
>>>         print(buf.size())

Parameters:

prefix (str) –
recurse (bool) –
remove_duplicate (bool) –

Return type:

Iterator[Tuple[str, Tensor]]

named_children()

Returns an iterator over immediate children modules, yielding both the name of the module as well as the module itself.

Yields:: (str, Module): Tuple containing a name and child module

Example:

>>> # xdoctest: +SKIP("undefined vars")
>>> for name, module in model.named_children():
>>>     if name in ['conv4', 'conv5']:
>>>         print(module)

Return type:: Iterator[Tuple[str, Module]]

named_modules(memo=None, prefix='', remove_duplicate=True)

Returns an iterator over all modules in the network, yielding both the name of the module as well as the module itself.

Args:: memo: a memo to store the set of modules already added to the result prefix: a prefix that will be added to the name of the module remove_duplicate: whether to remove the duplicated module instances in the result

or not
Yields:: (str, Module): Tuple of name and module
Note:: Duplicate modules are returned only once. In the following example, l will be returned only once.

Example:

>>> l = nn.Linear(2, 2)
>>> net = nn.Sequential(l, l)
>>> for idx, m in enumerate(net.named_modules()):
...     print(idx, '->', m)

0 -> ('', Sequential(
  (0): Linear(in_features=2, out_features=2, bias=True)
  (1): Linear(in_features=2, out_features=2, bias=True)
))
1 -> ('0', Linear(in_features=2, out_features=2, bias=True))

Parameters:

memo (Set[Module] | None) –
prefix (str) –
remove_duplicate (bool) –

named_parameters(prefix='', recurse=True, remove_duplicate=True)

Returns an iterator over module parameters, yielding both the name of the parameter as well as the parameter itself.

Args:

prefix (str): prefix to prepend to all parameter names. recurse (bool): if True, then yields parameters of this module

and all submodules. Otherwise, yields only parameters that are direct members of this module.

remove_duplicate (bool, optional): whether to remove the duplicated: parameters in the result. Defaults to True.

Yields:

(str, Parameter): Tuple containing the name and parameter

Example:

>>> # xdoctest: +SKIP("undefined vars")
>>> for name, param in self.named_parameters():
>>>     if name in ['bias']:
>>>         print(param.size())

Parameters:

prefix (str) –
recurse (bool) –
remove_duplicate (bool) –

Return type:

Iterator[Tuple[str, Parameter]]

obs_to_tensor(observation)

Convert an input observation to a PyTorch tensor that can be fed to a model. Includes sugar-coating to handle different observations (e.g. normalizing images).

Parameters:: observation (ndarray | Dict[str, ndarray]) – the input observation
Returns:: The observation as PyTorch tensor and whether the observation is vectorized or not
Return type:: Tuple[Tensor, bool]

parameters(recurse=True)

Returns an iterator over module parameters.

This is typically passed to an optimizer.

Args:

recurse (bool): if True, then yields parameters of this module: and all submodules. Otherwise, yields only parameters that are direct members of this module.

Yields:

Parameter: module parameter

Example:

>>> # xdoctest: +SKIP("undefined vars")
>>> for param in model.parameters():
>>>     print(type(param), param.size())
<class 'torch.Tensor'> (20L,)
<class 'torch.Tensor'> (20L, 1L, 5L, 5L)

Parameters:: recurse (bool) –
Return type:: Iterator[Parameter]

parameters_to_vector()

Convert the parameters to a 1D vector.

Returns:
Return type:: ndarray

predict(observation, state=None, episode_start=None, deterministic=False)

Get the policy action from an observation (and optional hidden state). Includes sugar-coating to handle different observations (e.g. normalizing images).

Parameters:

observation (ndarray | Dict[str, ndarray]) – the input observation
state (Tuple[ndarray, ...] | None) – The last hidden states (can be None, used in recurrent policies)
episode_start (ndarray | None) – The last masks (can be None, used in recurrent policies) this correspond to beginning of episodes, where the hidden states of the RNN must be reset.
deterministic (bool) – Whether or not to return deterministic actions.

Returns:

the model’s action and the next hidden state (used in recurrent policies)

Return type:

Tuple[ndarray, Tuple[ndarray, …] | None]

predict_values(obs)

Get the estimated values according to the current policy given the observations.

Parameters:: obs (Tensor) – Observation
Returns:: the estimated values.
Return type:: Tensor

register_backward_hook(hook)

Registers a backward hook on the module.

This function is deprecated in favor of register_full_backward_hook() and the behavior of this function will change in future versions.

Returns:

torch.utils.hooks.RemovableHandle:: a handle that can be used to remove the added hook by calling handle.remove()

Parameters:: hook (Callable[[Module, Tuple[Tensor, ...] | Tensor, Tuple[Tensor, ...] | Tensor], None | Tuple[Tensor, ...] | Tensor]) –
Return type:: RemovableHandle

register_buffer(name, tensor, persistent=True)

Adds a buffer to the module.

This is typically used to register a buffer that should not to be considered a model parameter. For example, BatchNorm’s running_mean is not a parameter, but is part of the module’s state. Buffers, by default, are persistent and will be saved alongside parameters. This behavior can be changed by setting persistent to False. The only difference between a persistent buffer and a non-persistent buffer is that the latter will not be a part of this module’s state_dict.

Buffers can be accessed as attributes using given names.

Args:

name (str): name of the buffer. The buffer can be accessed: from this module using the given name
tensor (Tensor or None): buffer to be registered. If None, then operations: that run on buffers, such as cuda, are ignored. If None, the buffer is not included in the module’s state_dict.
persistent (bool): whether the buffer is part of this module’s: state_dict.

Example:

>>> # xdoctest: +SKIP("undefined vars")
>>> self.register_buffer('running_mean', torch.zeros(num_features))

Parameters:

name (str) –
tensor (Tensor | None) –
persistent (bool) –

Return type:

None

register_forward_hook(hook, *, prepend=False, with_kwargs=False)

Registers a forward hook on the module.

The hook will be called every time after forward() has computed an output.

If with_kwargs is False or not specified, the input contains only the positional arguments given to the module. Keyword arguments won’t be passed to the hooks and only to the forward. The hook can modify the output. It can modify the input inplace but it will not have effect on forward since this is called after forward() is called. The hook should have the following signature:

hook(module, args, output) -> None or modified output

If with_kwargs is True, the forward hook will be passed the kwargs given to the forward function and be expected to return the output possibly modified. The hook should have the following signature:

hook(module, args, kwargs, output) -> None or modified output

Args:

hook (Callable): The user defined hook to be registered. prepend (bool): If True, the provided hook will be fired

before all existing forward hooks on this torch.nn.modules.Module. Otherwise, the provided hook will be fired after all existing forward hooks on this torch.nn.modules.Module. Note that global forward hooks registered with register_module_forward_hook() will fire before all hooks registered by this method. Default: False

with_kwargs (bool): If True, the hook will be passed the: kwargs given to the forward function. Default: False

Returns:

torch.utils.hooks.RemovableHandle:: a handle that can be used to remove the added hook by calling handle.remove()

Parameters:

hook (Callable[[T, Tuple[Any, ...], Any], Any | None] | Callable[[T, Tuple[Any, ...], Dict[str, Any], Any], Any | None]) –
prepend (bool) –
with_kwargs (bool) –

Return type:

RemovableHandle

register_forward_pre_hook(hook, *, prepend=False, with_kwargs=False)

Registers a forward pre-hook on the module.

The hook will be called every time before forward() is invoked.

If with_kwargs is false or not specified, the input contains only the positional arguments given to the module. Keyword arguments won’t be passed to the hooks and only to the forward. The hook can modify the input. User can either return a tuple or a single modified value in the hook. We will wrap the value into a tuple if a single value is returned (unless that value is already a tuple). The hook should have the following signature:

hook(module, args) -> None or modified input

If with_kwargs is true, the forward pre-hook will be passed the kwargs given to the forward function. And if the hook modifies the input, both the args and kwargs should be returned. The hook should have the following signature:

hook(module, args, kwargs) -> None or a tuple of modified input and kwargs

Args:

hook (Callable): The user defined hook to be registered. prepend (bool): If true, the provided hook will be fired before

all existing forward_pre hooks on this torch.nn.modules.Module. Otherwise, the provided hook will be fired after all existing forward_pre hooks on this torch.nn.modules.Module. Note that global forward_pre hooks registered with register_module_forward_pre_hook() will fire before all hooks registered by this method. Default: False

with_kwargs (bool): If true, the hook will be passed the kwargs: given to the forward function. Default: False

Returns:

torch.utils.hooks.RemovableHandle:: a handle that can be used to remove the added hook by calling handle.remove()

Parameters:

hook (Callable[[T, Tuple[Any, ...]], Any | None] | Callable[[T, Tuple[Any, ...], Dict[str, Any]], Tuple[Any, Dict[str, Any]] | None]) –
prepend (bool) –
with_kwargs (bool) –

Return type:

RemovableHandle

register_full_backward_hook(hook, prepend=False)

Registers a backward hook on the module.

The hook will be called every time the gradients with respect to a module are computed, i.e. the hook will execute if and only if the gradients with respect to module outputs are computed. The hook should have the following signature:

hook(module, grad_input, grad_output) -> tuple(Tensor) or None

The grad_input and grad_output are tuples that contain the gradients with respect to the inputs and outputs respectively. The hook should not modify its arguments, but it can optionally return a new gradient with respect to the input that will be used in place of grad_input in subsequent computations. grad_input will only correspond to the inputs given as positional arguments and all kwarg arguments are ignored. Entries in grad_input and grad_output will be None for all non-Tensor arguments.

For technical reasons, when this hook is applied to a Module, its forward function will receive a view of each Tensor passed to the Module. Similarly the caller will receive a view of each Tensor returned by the Module’s forward function.

Warning

Modifying inputs or outputs inplace is not allowed when using backward hooks and will raise an error.

Args:

hook (Callable): The user-defined hook to be registered. prepend (bool): If true, the provided hook will be fired before

all existing backward hooks on this torch.nn.modules.Module. Otherwise, the provided hook will be fired after all existing backward hooks on this torch.nn.modules.Module. Note that global backward hooks registered with register_module_full_backward_hook() will fire before all hooks registered by this method.

Returns:

torch.utils.hooks.RemovableHandle:: a handle that can be used to remove the added hook by calling handle.remove()

Parameters:

hook (Callable[[Module, Tuple[Tensor, ...] | Tensor, Tuple[Tensor, ...] | Tensor], None | Tuple[Tensor, ...] | Tensor]) –
prepend (bool) –

Return type:

RemovableHandle

register_full_backward_pre_hook(hook, prepend=False)

Registers a backward pre-hook on the module.

The hook will be called every time the gradients for the module are computed. The hook should have the following signature:

hook(module, grad_output) -> Tensor or None

The grad_output is a tuple. The hook should not modify its arguments, but it can optionally return a new gradient with respect to the output that will be used in place of grad_output in subsequent computations. Entries in grad_output will be None for all non-Tensor arguments.

For technical reasons, when this hook is applied to a Module, its forward function will receive a view of each Tensor passed to the Module. Similarly the caller will receive a view of each Tensor returned by the Module’s forward function.

Warning

Modifying inputs inplace is not allowed when using backward hooks and will raise an error.

Args:

hook (Callable): The user-defined hook to be registered. prepend (bool): If true, the provided hook will be fired before

all existing backward_pre hooks on this torch.nn.modules.Module. Otherwise, the provided hook will be fired after all existing backward_pre hooks on this torch.nn.modules.Module. Note that global backward_pre hooks registered with register_module_full_backward_pre_hook() will fire before all hooks registered by this method.

Returns:

torch.utils.hooks.RemovableHandle:: a handle that can be used to remove the added hook by calling handle.remove()

Parameters:

hook (Callable[[Module, Tuple[Tensor, ...] | Tensor], None | Tuple[Tensor, ...] | Tensor]) –
prepend (bool) –

Return type:

RemovableHandle

register_load_state_dict_post_hook(hook)

Registers a post hook to be run after module’s load_state_dict is called.

It should have the following signature::: hook(module, incompatible_keys) -> None

The module argument is the current module that this hook is registered on, and the incompatible_keys argument is a NamedTuple consisting of attributes missing_keys and unexpected_keys. missing_keys is a list of str containing the missing keys and unexpected_keys is a list of str containing the unexpected keys.

The given incompatible_keys can be modified inplace if needed.

Note that the checks performed when calling load_state_dict() with strict=True are affected by modifications the hook makes to missing_keys or unexpected_keys, as expected. Additions to either set of keys will result in an error being thrown when strict=True, and clearing out both missing and unexpected keys will avoid an error.

Returns:

torch.utils.hooks.RemovableHandle:: a handle that can be used to remove the added hook by calling handle.remove()

register_module(name, module)

Alias for add_module().

Parameters:

name (str) –
module (Module | None) –

Return type:

None

register_parameter(name, param)

Adds a parameter to the module.

The parameter can be accessed as an attribute using given name.

Args:

name (str): name of the parameter. The parameter can be accessed: from this module using the given name
param (Parameter or None): parameter to be added to the module. If: None, then operations that run on parameters, such as cuda, are ignored. If None, the parameter is not included in the module’s state_dict.

Parameters:

name (str) –
param (Parameter | None) –

Return type:

None

register_state_dict_pre_hook(hook): These hooks will be called with arguments: self, prefix, and keep_vars before calling state_dict on self. The registered hooks can be used to perform pre-processing before the state_dict call is made.

requires_grad_(requires_grad=True)

Change if autograd should record operations on parameters in this module.

This method sets the parameters’ requires_grad attributes in-place.

This method is helpful for freezing part of the module for finetuning or training parts of a model individually (e.g., GAN training).

See locally-disable-grad-doc for a comparison between .requires_grad_() and several similar mechanisms that may be confused with it.

Args:

requires_grad (bool): whether autograd should record operations on: parameters in this module. Default: True.

Returns:

Module: self

Parameters:

self (T) –
requires_grad (bool) –

Return type:

T

reset_noise(n_envs=1)

Sample new weights for the exploration matrix.

Parameters:: n_envs (int) –
Return type:: None

save(path)

Save model to a given location.

Parameters:: path (str) –
Return type:: None

scale_action(action)

Rescale the action from [low, high] to [-1, 1] (no need for symmetric action space)

Parameters:: action (ndarray) – Action to scale
Returns:: Scaled action
Return type:: ndarray

set_extra_state(state)

This function is called from load_state_dict() to handle any extra state found within the state_dict. Implement this function and a corresponding get_extra_state() for your module if you need to store extra state within its state_dict.

Args:: state (dict): Extra state from the state_dict

Parameters:: state (Any) –

set_training_mode(mode)

Put the policy in either training or evaluation mode.

This affects certain modules, such as batch normalisation and dropout.

Parameters:: mode (bool) – if true, set to training mode, else set to evaluation mode
Return type:: None

share_memory()

See torch.Tensor.share_memory_()

Parameters:: self (T) –
Return type:: T

property squash_output: bool: (bool) Getter for squash_output.

state_dict(*args, destination=None, prefix='', keep_vars=False)

Returns a dictionary containing references to the whole state of the module.

Both parameters and persistent buffers (e.g. running averages) are included. Keys are corresponding parameter and buffer names. Parameters and buffers set to None are not included.

Note

The returned object is a shallow copy. It contains references to the module’s parameters and buffers.

Warning

Currently state_dict() also accepts positional arguments for destination, prefix and keep_vars in order. However, this is being deprecated and keyword arguments will be enforced in future releases.

Warning

Please avoid the use of argument destination as it is not designed for end-users.

Args:

destination (dict, optional): If provided, the state of module will: be updated into the dict and the same object is returned. Otherwise, an OrderedDict will be created and returned. Default: None.
prefix (str, optional): a prefix added to parameter and buffer: names to compose the keys in state_dict. Default: ''.
keep_vars (bool, optional): by default the Tensor s: returned in the state dict are detached from autograd. If it’s set to True, detaching will not be performed. Default: False.

Returns:

dict:: a dictionary containing a whole state of the module

Example:

>>> # xdoctest: +SKIP("undefined vars")
>>> module.state_dict().keys()
['bias', 'weight']

to(*args, **kwargs)

Moves and/or casts the parameters and buffers.

This can be called as

to(device=None, dtype=None, non_blocking=False)

to(dtype, non_blocking=False)

to(tensor, non_blocking=False)

to(memory_format=torch.channels_last)

Its signature is similar to torch.Tensor.to(), but only accepts floating point or complex dtypes. In addition, this method will only cast the floating point or complex parameters and buffers to dtype (if given). The integral parameters and buffers will be moved device, if that is given, but with dtypes unchanged. When non_blocking is set, it tries to convert/move asynchronously with respect to the host if possible, e.g., moving CPU Tensors with pinned memory to CUDA devices.

See below for examples.

Note

This method modifies the module in-place.

Args:

device (torch.device): the desired device of the parameters: and buffers in this module
dtype (torch.dtype): the desired floating point or complex dtype of: the parameters and buffers in this module
tensor (torch.Tensor): Tensor whose dtype and device are the desired: dtype and device for all parameters and buffers in this module
memory_format (torch.memory_format): the desired memory: format for 4D parameters and buffers in this module (keyword only argument)

Returns:

Module: self

Examples:

>>> # xdoctest: +IGNORE_WANT("non-deterministic")
>>> linear = nn.Linear(2, 2)
>>> linear.weight
Parameter containing:
tensor([[ 0.1913, -0.3420],
        [-0.5113, -0.2325]])
>>> linear.to(torch.double)
Linear(in_features=2, out_features=2, bias=True)
>>> linear.weight
Parameter containing:
tensor([[ 0.1913, -0.3420],
        [-0.5113, -0.2325]], dtype=torch.float64)
>>> # xdoctest: +REQUIRES(env:TORCH_DOCTEST_CUDA1)
>>> gpu1 = torch.device("cuda:1")
>>> linear.to(gpu1, dtype=torch.half, non_blocking=True)
Linear(in_features=2, out_features=2, bias=True)
>>> linear.weight
Parameter containing:
tensor([[ 0.1914, -0.3420],
        [-0.5112, -0.2324]], dtype=torch.float16, device='cuda:1')
>>> cpu = torch.device("cpu")
>>> linear.to(cpu)
Linear(in_features=2, out_features=2, bias=True)
>>> linear.weight
Parameter containing:
tensor([[ 0.1914, -0.3420],
        [-0.5112, -0.2324]], dtype=torch.float16)

>>> linear = nn.Linear(2, 2, bias=None).to(torch.cdouble)
>>> linear.weight
Parameter containing:
tensor([[ 0.3741+0.j,  0.2382+0.j],
        [ 0.5593+0.j, -0.4443+0.j]], dtype=torch.complex128)
>>> linear(torch.ones(3, 2, dtype=torch.cdouble))
tensor([[0.6122+0.j, 0.1150+0.j],
        [0.6122+0.j, 0.1150+0.j],
        [0.6122+0.j, 0.1150+0.j]], dtype=torch.complex128)

to_empty(*, device)

Moves the parameters and buffers to the specified device without copying storage.

Args:

device (torch.device): The desired device of the parameters: and buffers in this module.

Returns:

Module: self

Parameters:

self (T) –
device (str | device) –

Return type:

T

train(mode=True)

Sets the module in training mode.

This has any effect only on certain modules. See documentations of particular modules for details of their behaviors in training/evaluation mode, if they are affected, e.g. Dropout, BatchNorm, etc.

Args:

mode (bool): whether to set training mode (True) or evaluation: mode (False). Default: True.

Returns:

Module: self

Parameters:

self (T) –
mode (bool) –

Return type:

T

type(dst_type)

Casts all parameters and buffers to dst_type.

Note

This method modifies the module in-place.

Args:: dst_type (type or string): the desired type
Returns:: Module: self

Parameters:

self (T) –
dst_type (dtype | str) –

Return type:

T

unscale_action(scaled_action)

Rescale the action from [-1, 1] to [low, high] (no need for symmetric action space)

Parameters:: scaled_action (ndarray) – Action to un-scale
Return type:: ndarray

xpu(device=None)

Moves all model parameters and buffers to the XPU.

This also makes associated parameters and buffers different objects. So it should be called before constructing optimizer if the module will live on XPU while being optimized.

Note

This method modifies the module in-place.

Arguments:

device (int, optional): if specified, all parameters will be: copied to that device

Returns:

Module: self

Parameters:

self (T) –
device (int | device | None) –

Return type:

T

zero_grad(set_to_none=True)

Sets gradients of all model parameters to zero. See similar function under torch.optim.Optimizer for more context.

Args:

set_to_none (bool): instead of setting to zero, set the grads to None.: See torch.optim.Optimizer.zero_grad() for details.

Parameters:: set_to_none (bool) –
Return type:: None