chainer.links.StatefulZoneoutLSTM

class chainer.links.StatefulZoneoutLSTM(in_size, out_size, c_ratio=0.5, h_ratio=0.5, **kwargs)

Methods

__call__(x)

Updates the internal state and returns the LSTM outputs.

Parameters:x (Variable) – A new batch from the input sequence. Returns:Outputs of updated LSTM units. Return type:Variable

__getitem__(name)

Equivalent to getattr.

add_link(name, link)

Registers a child link to this chain.

Deprecated since version v2.0.0: Assign the child link directly to an attribute within init_scope() instead. For example, the following code

chain.add_link('l1', L.Linear(3, 5))

can be replaced by the following line.

with chain.init_scope():
    chain.l1 = L.Linear(3, 5)

The latter is easier for IDEs to keep track of the attribute’s type.

Parameters:

• name (str) – Name of the child link. This name is also used as the attribute name.
• link (Link) – The link object to be registered.

add_param(name, shape=None, dtype=<class 'numpy.float32'>, initializer=None)

Registers a parameter to the link.

Deprecated since version v2.0.0: Assign a Parameter object directly to an attribute within init_scope() instead. For example, the following code

link.add_param('W', shape=(5, 3))

can be replaced by the following assignment.

with link.init_scope():
    link.W = chainer.Parameter(None, (5, 3))

The latter is easier for IDEs to keep track of the attribute’s type.

Parameters:

• name (str) – Name of the parameter. This name is also used as the attribute name.
• shape (int or tuple of ints) – Shape of the parameter array. If it is omitted, the parameter variable is left uninitialized.
• dtype – Data type of the parameter array.
• initializer – If it is not None, the data is initialized with the given initializer. If it is an array, the data is directly initialized by it. If it is callable, it is used as a weight initializer. Note that in these cases, dtype argument is ignored.

add_persistent(name, value)

Registers a persistent value to the link.

The registered value is saved and loaded on serialization and deserialization. The value is set to an attribute of the link.

Parameters:

• name (str) – Name of the persistent value. This name is also used for the attribute name.
• value – Value to be registered.

addgrads(link)

children()

cleargrads()

Clears all gradient arrays.

This method should be called before the backward computation at every iteration of the optimization.

copy()

copyparams(link)

disable_update()

Disables update rules of all parameters under the link hierarchy.

This method sets the enabled flag of the update rule of each parameter variable to False.

enable_update()

Enables update rules of all parameters under the link hierarchy.

This method sets the enabled flag of the update rule of each parameter variable to True.

init_scope()

Creates an initialization scope.

This method returns a context manager object that enables registration of parameters (and links for Chain) by an assignment. A Parameter object can be automatically registered by assigning it to an attribute under this context manager.

Example

In most cases, the parameter registration is done in the initializer method. Using the init_scope method, we can simply assign a Parameter object to register it to the link.

class MyLink(chainer.Link):
    def __init__(self):
        super().__init__()
        with self.init_scope():
            self.W = chainer.Parameter(0, (10, 5))
            self.b = chainer.Parameter(0, (5,))

links(skipself=False)

namedlinks(skipself=False)

namedparams(include_uninit=True)

params(include_uninit=True)

register_persistent(name)

Registers an attribute of a given name as a persistent value.

This is a convenient method to register an existing attribute as a persistent value. If name has been already registered as a parameter, this method removes it from the list of parameter names and re-registers it as a persistent value.

Parameters:name (str) – Name of the attribute to be registered.

reset_state()

Resets the internal state.

It sets None to the c and h attributes.

serialize(serializer)

set_state(c, h)

Sets the internal state.

It sets the c and h attributes.

Parameters:

• c (Variable) – A new cell states of LSTM units.
• h (Variable) – A new output at the previous time step.

to_cpu()

to_gpu(device=None)

zerograds()

Initializes all gradient arrays by zero.

This method can be used for the same purpose of cleargrads, but less efficient. This method is left for backward compatibility.

Deprecated since version v1.15: Use cleargrads() instead.