Catalano.Neuro.ActivationFunction

Class BipolarSigmoidFunction

java.lang.Object

Catalano.Neuro.ActivationFunction.BipolarSigmoidFunction

All Implemented Interfaces:

IActivationFunction

public class BipolarSigmoidFunction
extends java.lang.Object
implements IActivationFunction

Bipolar sigmoid activation function.

Constructor Summary

Constructors

Constructor and Description
BipolarSigmoidFunction() Initializes a new instance of the BipolarSigmoidFunction class.
BipolarSigmoidFunction(double alpha) Initializes a new instance of the BipolarSigmoidFunction class.

Method Summary

Modifier and Type	Method and Description
double	Derivative(double x) Calculates function derivative.
double	Derivative2(double x) Calculates function derivative.
double	Function(double x) Calculates function value.
double	getAlpha() Get Sigmoid's alpha value.
void	setAlpha(double alpha) Set Sigmoid's alpha value.

Methods inherited from class java.lang.Object

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

Constructor Detail

BipolarSigmoidFunction

public BipolarSigmoidFunction()

Initializes a new instance of the BipolarSigmoidFunction class.

BipolarSigmoidFunction

public BipolarSigmoidFunction(double alpha)

Initializes a new instance of the BipolarSigmoidFunction class.

Parameters:

alpha - Sigmoid's alpha value.

Method Detail

getAlpha

public double getAlpha()

Get Sigmoid's alpha value. The value determines steepness of the function. Increasing value of this property changes sigmoid to look more like a threshold function. Decreasing value of this property makes sigmoid to be very smooth (slowly growing from its minimum value to its maximum value).

Returns:

Alpha value.

setAlpha

public void setAlpha(double alpha)

Set Sigmoid's alpha value. The value determines steepness of the function. Increasing value of this property changes sigmoid to look more like a threshold function. Decreasing value of this property makes sigmoid to be very smooth (slowly growing from its minimum value to its maximum value).

Parameters:

alpha - Alpha value.

Function

public double Function(double x)

Description copied from interface: IActivationFunction

Calculates function value.

Specified by:

Function in interface IActivationFunction

Parameters:

x - Function input value.

Returns:

Function output value, f(x).

Derivative

public double Derivative(double x)

Description copied from interface: IActivationFunction

Calculates function derivative.

Specified by:

Derivative in interface IActivationFunction

Parameters:

x - Function input value.

Returns:

Function derivative, f'(x).

Derivative2

public double Derivative2(double x)

Description copied from interface: IActivationFunction

Calculates function derivative.

Specified by:

Derivative2 in interface IActivationFunction

Parameters:

x - Function output value - the value, which was obtained with the help of Function method.

Returns:

Function derivative, f'(x).