org.neuroph.core.transfer
Class Sigmoid

java.lang.Object
  extended by org.neuroph.core.transfer.TransferFunction
      extended by 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))
 

Author:
Zoran Sevarac
See Also:
Serialized Form

Constructor Summary
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(java.util.Properties properties)
          Creates an instance of Sigmoid neuron transfer function with the specified properties.
 
Method Summary
 double getDerivative(double net)
          Returns the first derivative of this function.
 double getOutput(double net)
          Returns the ouput of this function.
 double getSlope()
          Returns the slope parametar of this function
 void setSlope(java.lang.Double slope)
          Sets the slope parametar for this function
 
Methods inherited from class org.neuroph.core.transfer.TransferFunction
toString
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, 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(java.util.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(java.lang.Double slope)
Sets the slope parametar for this function

Parameters:
slope - value for the slope parametar

getOutput

public double getOutput(double net)
Description copied from class: TransferFunction
Returns the ouput of this function.

Specified by:
getOutput in class TransferFunction
Parameters:
net - net input

getDerivative

public double getDerivative(double net)
Description copied from class: TransferFunction
Returns the first derivative of this function.

Overrides:
getDerivative in class TransferFunction
Parameters:
net - net input