Fully-connected RNN where the output is to be fed back to input.
layer_simple_rnn(
object,
units,
activation = "tanh",
use_bias = TRUE,
return_sequences = FALSE,
return_state = FALSE,
go_backwards = FALSE,
stateful = FALSE,
unroll = FALSE,
kernel_initializer = "glorot_uniform",
recurrent_initializer = "orthogonal",
bias_initializer = "zeros",
kernel_regularizer = NULL,
recurrent_regularizer = NULL,
bias_regularizer = NULL,
activity_regularizer = NULL,
kernel_constraint = NULL,
recurrent_constraint = NULL,
bias_constraint = NULL,
dropout = 0,
recurrent_dropout = 0,
input_shape = NULL,
batch_input_shape = NULL,
batch_size = NULL,
dtype = NULL,
name = NULL,
trainable = NULL,
weights = NULL
)
Model or layer object
Positive integer, dimensionality of the output space.
Activation function to use. Default: hyperbolic tangent
(tanh
). If you pass NULL
, no activation is applied
(ie. "linear" activation: a(x) = x
).
Boolean, whether the layer uses a bias vector.
Boolean. Whether to return the last output in the output sequence, or the full sequence.
Boolean (default FALSE). Whether to return the last state in addition to the output.
Boolean (default FALSE). If TRUE, process the input sequence backwards and return the reversed sequence.
Boolean (default FALSE). If TRUE, the last state for each sample at index i in a batch will be used as initial state for the sample of index i in the following batch.
Boolean (default FALSE). If TRUE, the network will be unrolled, else a symbolic loop will be used. Unrolling can speed-up a RNN, although it tends to be more memory-intensive. Unrolling is only suitable for short sequences.
Initializer for the kernel
weights matrix, used
for the linear transformation of the inputs.
Initializer for the recurrent_kernel
weights
matrix, used for the linear transformation of the recurrent state.
Initializer for the bias vector.
Regularizer function applied to the kernel
weights matrix.
Regularizer function applied to the
recurrent_kernel
weights matrix.
Regularizer function applied to the bias vector.
Regularizer function applied to the output of the layer (its "activation")..
Constraint function applied to the kernel
weights
matrix.
Constraint function applied to the
recurrent_kernel
weights matrix.
Constraint function applied to the bias vector.
Float between 0 and 1. Fraction of the units to drop for the linear transformation of the inputs.
Float between 0 and 1. Fraction of the units to drop for the linear transformation of the recurrent state.
Dimensionality of the input (integer) not including the samples axis. This argument is required when using this layer as the first layer in a model.
Shapes, including the batch size. For instance,
batch_input_shape=c(10, 32)
indicates that the expected input will be
batches of 10 32-dimensional vectors. batch_input_shape=list(NULL, 32)
indicates batches of an arbitrary number of 32-dimensional vectors.
Fixed batch size for layer
The data type expected by the input, as a string (float32
,
float64
, int32
...)
An optional name string for the layer. Should be unique in a model (do not reuse the same name twice). It will be autogenerated if it isn't provided.
Whether the layer weights will be updated during training.
Initial weights for layer.
3D tensor with shape (batch_size, timesteps, input_dim)
,
(Optional) 2D tensors with shape (batch_size, output_dim)
.
if return_state
: a list of tensors. The first tensor is
the output. The remaining tensors are the last states,
each with shape (batch_size, units)
.
if return_sequences
: 3D tensor with shape
(batch_size, timesteps, units)
.
else, 2D tensor with shape (batch_size, units)
.
This layer supports masking for input data with a variable number
of timesteps. To introduce masks to your data,
use an embedding layer with the mask_zero
parameter
set to TRUE
.
You can set RNN layers to be 'stateful', which means that the states computed for the samples in one batch will be reused as initial states for the samples in the next batch. This assumes a one-to-one mapping between samples in different successive batches.
To enable statefulness:
Specify stateful=TRUE
in the layer constructor.
Specify a fixed batch size for your model. For sequential models,
pass batch_input_shape = c(...)
to the first layer in your model.
For functional models with 1 or more Input layers, pass
batch_shape = c(...)
to all the first layers in your model.
This is the expected shape of your inputs including the batch size.
It should be a vector of integers, e.g. c(32, 10, 100)
.
Specify shuffle = FALSE
when calling fit().
To reset the states of your model, call reset_states()
on either
a specific layer, or on your entire model.
You can specify the initial state of RNN layers symbolically by calling
them with the keyword argument initial_state
. The value of
initial_state
should be a tensor or list of tensors representing
the initial state of the RNN layer.
You can specify the initial state of RNN layers numerically by
calling reset_states
with the keyword argument states
. The value of
states
should be a numpy array or list of numpy arrays representing
the initial state of the RNN layer.
Other recurrent layers:
layer_cudnn_gru()
,
layer_cudnn_lstm()
,
layer_gru()
,
layer_lstm()