org.encog.neural.networks.layers
Class BasicLayer

java.lang.Object
  org.encog.neural.networks.layers.BasicLayer

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable, Layer, EncogPersistedObject

Direct Known Subclasses:

ContextLayer, RadialBasisFunctionLayer

public class BasicLayer
extends java.lang.Object
implements Layer, java.io.Serializable

Basic functionality that most of the neural layers require. The basic layer is often used by itself to implement forward or recurrent layers. Other layer types are based on the basic layer as well. The layer will either have thresholds are not. Thresholds are values that correspond to each of the neurons. The threshold values will be added to the output calculated for each neuron. Together with the weight matrix the threshold values make up the memory of the neural network. When the neural network is trained, these threshold values (along with the weight matrix values) will be modified.

Author:

jheaton

See Also:

Serialized Form

Constructor Summary

BasicLayer()
Default constructor, mainly so the workbench can easily create a default layer.

BasicLayer(ActivationFunction activationFunction, boolean hasThreshold, int neuronCount)
Construct this layer with a non-default threshold function.

BasicLayer(int neuronCount)
Construct this layer with a sigmoid threshold function.

Method Summary

void	addNext(Layer next) Add a layer as the next layer.
void	addNext(Layer next, SynapseType type) Add a layer to this layer.
void	addSynapse(Synapse synapse) Add a synapse to the list of outbound synapses.
java.lang.Object	clone() Clone this object.
NeuralData	compute(NeuralData pattern) Compute the outputs for this layer given the input pattern.
Persistor	createPersistor() Create a persistor for this layer.
ActivationFunction	getActivationFunction()
java.lang.String	getDescription()
java.lang.String	getName()
int	getNeuronCount() Get the neuron count for this layer.
java.util.List<Synapse>	getNext() Get a list of all of the outbound synapse connections from this layer.
java.util.Collection<Layer>	getNextLayers()
double[]	getThreshold()
double	getThreshold(int index) Get an individual threshold value.
int	getX()
int	getY()
boolean	hasThreshold()
boolean	isConnectedTo(Layer layer) Determine if this layer is connected to another layer.
boolean	isSelfConnected()
void	process(NeuralData pattern) Process the input pattern.
NeuralData	recur() Get the output from this layer when called in a recurrent manor.
void	setActivationFunction(ActivationFunction f) Set the activation function for this layer.
void	setDescription(java.lang.String description) Set the description of this object.
void	setName(java.lang.String name) Set the name of this object.
void	setNeuronCount(int neuronCount) Set the neuron count.
void	setThreshold(double[] d) Set the threshold array.
void	setThreshold(int index, double d) Set the specified threshold value.
void	setX(int x) Set the x coordinate for this layer.
void	setY(int y) Set the y coordinate for this layer.
java.lang.String	toString()

Methods inherited from class java.lang.Object

equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

BasicLayer

public BasicLayer()

Default constructor, mainly so the workbench can easily create a default layer.

BasicLayer

public BasicLayer(ActivationFunction activationFunction,
                  boolean hasThreshold,
                  int neuronCount)

Construct this layer with a non-default threshold function.

Parameters:

activationFunction - The threshold function to use.

neuronCount - How many neurons in this layer.

hasThreshold - True if this layer has threshold values.

BasicLayer

public BasicLayer(int neuronCount)

Construct this layer with a sigmoid threshold function.

Parameters:

neuronCount - How many neurons in this layer.

Method Detail

addNext

public void addNext(Layer next)

Add a layer as the next layer. The layer will be added with a weighted synapse.

Specified by:

addNext in interface Layer

Parameters:

next - THe next layer.

addNext

public void addNext(Layer next,
                    SynapseType type)

Description copied from interface: Layer

Add a layer to this layer. The "next" layer being added will receive input from this layer. You can also add a layer to itself, this will create a self-connected layer.

Specified by:

addNext in interface Layer

Parameters:

next - The next layer to add.

type - The synapse type to use for this layer.

addSynapse

public void addSynapse(Synapse synapse)

Add a synapse to the list of outbound synapses. Usually you should simply call the addLayer method to add to the outbound list.

Specified by:

addSynapse in interface Layer

Parameters:

synapse - The synapse to add.

clone

public java.lang.Object clone()

Clone this object.

Specified by:

clone in interface Layer

Specified by:

clone in interface EncogPersistedObject

Overrides:

clone in class java.lang.Object

Returns:

A cloned version of this object.

compute

public NeuralData compute(NeuralData pattern)

Compute the outputs for this layer given the input pattern. The output is also stored in the fire instance variable.

Specified by:

compute in interface Layer

Parameters:

pattern - The input pattern.

Returns:

The output from this layer.

createPersistor

public Persistor createPersistor()

Create a persistor for this layer.

Specified by:

createPersistor in interface EncogPersistedObject

Returns:

The new persistor.

getActivationFunction

public ActivationFunction getActivationFunction()

Specified by:

getActivationFunction in interface Layer

Returns:

The activation function for this layer.

getDescription

public java.lang.String getDescription()

Specified by:

getDescription in interface EncogPersistedObject

Returns:

the description

getName

public java.lang.String getName()

Specified by:

getName in interface EncogPersistedObject

Returns:

the name

getNeuronCount

public int getNeuronCount()

Get the neuron count for this layer.

Specified by:

getNeuronCount in interface Layer

Returns:

the neuronCount

getNext

public java.util.List<Synapse> getNext()

Description copied from interface: Layer

Get a list of all of the outbound synapse connections from this layer.

Specified by:

getNext in interface Layer

Returns:

The outbound synapse connections.

getNextLayers

public java.util.Collection<Layer> getNextLayers()

Specified by:

getNextLayers in interface Layer

Returns:

The list of layers that the outbound synapses connect to.

getThreshold

public double[] getThreshold()

Specified by:

getThreshold in interface Layer

Returns:

The threshold values.

getThreshold

public double getThreshold(int index)

Get an individual threshold value.

Specified by:

getThreshold in interface Layer

Parameters:

index - The threshold value to get.

Returns:

The threshold value.

getX

public int getX()

Specified by:

getX in interface Layer

Returns:

The x-coordinate. Used when the layer is displayed in a GUI.

getY

public int getY()

Specified by:

getY in interface Layer

Returns:

The y-coordinate. Used when the layer is displayed in a GUI.

hasThreshold

public boolean hasThreshold()

Specified by:

hasThreshold in interface Layer

Returns:

True if threshold values are present.

isConnectedTo

public boolean isConnectedTo(Layer layer)

Determine if this layer is connected to another layer.

Specified by:

isConnectedTo in interface Layer

Parameters:

layer - A layer to check and see if this layer is connected to.

Returns:

True if the two layers are connected.

isSelfConnected

public boolean isSelfConnected()

Returns:

True if this layer is connected to intself.

process

public void process(NeuralData pattern)

Process the input pattern. For the basic layer, nothing is done. This is how the context layer gets a chance to record the input. Other similar functions, where access is needed to the input.

Specified by:

process in interface Layer

Parameters:

pattern - The input to this layer.

recur

public NeuralData recur()

Get the output from this layer when called in a recurrent manor. For the BaiscLayer, this is not implemented.

Specified by:

recur in interface Layer

Returns:

The output when called in a recurrent way.

setActivationFunction

public void setActivationFunction(ActivationFunction f)

Set the activation function for this layer.

Specified by:

setActivationFunction in interface Layer

Parameters:

f - The activation function.

setDescription

public void setDescription(java.lang.String description)

Description copied from interface: EncogPersistedObject

Set the description of this object.

Specified by:

setDescription in interface EncogPersistedObject

Parameters:

description - the description to set

setName

public void setName(java.lang.String name)

Description copied from interface: EncogPersistedObject

Set the name of this object.

Specified by:

setName in interface EncogPersistedObject

Parameters:

name - the name to set

setNeuronCount

public void setNeuronCount(int neuronCount)

Set the neuron count. This just sets it, it does not make any adjustments to the class. To automatically change the neuron count refer to the pruning classes.

Specified by:

setNeuronCount in interface Layer

Parameters:

neuronCount - The new neuron count.

setThreshold

public void setThreshold(double[] d)

Set the threshold array. This does not modify any of the other values in the network, it just sets the threshold array. If you want to change the structure of the neural network you should use the pruning classes.

Specified by:

setThreshold in interface Layer

Parameters:

d - The new threshold array.

setThreshold

public void setThreshold(int index,
                         double d)

Set the specified threshold value.

Specified by:

setThreshold in interface Layer

Parameters:

index - The threshold value to set.

d - The value to set the threshold to.

setX

public void setX(int x)

Set the x coordinate for this layer. The coordinates are used when the layer must be displayed in a GUI situation.

Specified by:

setX in interface Layer

Parameters:

x - The x-coordinate.

setY

public void setY(int y)

Set the y coordinate for this layer. The coordinates are used when the layer must be displayed in a GUI situation.

Specified by:

setY in interface Layer

Parameters:

y - The y-coordinate.

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

Returns:

This object as a string.