org.neuroph.core.transfer

Class Sigmoid

java.lang.Object

org.neuroph.core.transfer.TransferFunction

org.neuroph.core.transfer.Sigmoid

All Implemented Interfaces:

java.io.Serializable

public class Sigmoid
extends TransferFunction
implements java.io.Serializable

 Sigmoid neuron transfer function.
 
 output = 1/(1+ e^(-slope*input))
 

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
Sigmoid() Creates an instance of Sigmoid neuron transfer function with default slope=1.
Sigmoid(double slope) Creates an instance of Sigmoid neuron transfer function with specified value for slope parametar.
Sigmoid(Properties properties) Creates an instance of Sigmoid neuron transfer function with the specified properties.

Method Summary

Modifier and Type	Method and Description
double	getDerivative(double net) Returns the first derivative of this function.
double	getOutput(double netInput) Returns the ouput of this function.
double	getSlope() Returns the slope parametar of this function
void	setSlope(double slope) Sets the slope parametar for this function

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Sigmoid

public Sigmoid()

Creates an instance of Sigmoid neuron transfer function with default slope=1.

Sigmoid

public Sigmoid(double slope)

Creates an instance of Sigmoid neuron transfer function with specified value for slope parametar.

Parameters:

slope - the slope parametar for the sigmoid function

Sigmoid

public Sigmoid(Properties properties)

Creates an instance of Sigmoid neuron transfer function with the specified properties.

Parameters:

properties - properties of the sigmoid function

Method Detail

getSlope

public double getSlope()

Returns the slope parametar of this function

Returns:

slope parametar of this function

setSlope

public void setSlope(double slope)

Sets the slope parametar for this function

Parameters:

slope - value for the slope parametar

getOutput

public double getOutput(double netInput)

Description copied from class: TransferFunction

Returns the ouput of this function.

Specified by:

getOutput in class TransferFunction

Parameters:

netInput - total input

getDerivative

public double getDerivative(double net)

Description copied from class: TransferFunction

Returns the first derivative of this function. Note: should this method should be abstract?

Overrides:

getDerivative in class TransferFunction

Parameters:

net - total input