boone.spike

Class PostsynapticPotential

java.lang.Object

boone.map.Function

boone.spike.PostsynapticPotential

All Implemented Interfaces:

Storable, java.lang.Cloneable

public class PostsynapticPotential
extends Function

This function models the effect of a spike generated by a SpikingNeuron to the overall potential of a the SpikingNeuron that receives the spike. Both neurons are connected by a SpikingLink. The PostsynapticPotential function is the default activation function for a SpikingLink. This enables a SpikingLink to model a biolgical synapse. By default a PostsynapticPotential models an excitatory effect.

PostsynapticPotential(t) := alpha * (e**-(lambda*t) - e**-(mu*t))

Version:

$Id: PostsynapticPotential.java 2285 2015-08-04 jmory $

Author:

Johannes Mory

Nested Class Summary

Nested classes/interfaces inherited from class boone.map.Function

Function.AboutEqual, Function.AtLeast, Function.AtMost, Function.CatmullRomSpline, Function.Clip, Function.Composition, Function.Exponential, Function.GreaterThan, Function.Identity, Function.LessThan, Function.NaturalSpline, Function.NotImplemented, Function.ReLU, Function.Scaled, Function.Sigmoid, Function.Signum, Function.SignumWithoutZero, Function.Sinus, Function.SoftMax, Function.Spline, Function.TanH

Constructor Summary

Constructors

Constructor and Description
PostsynapticPotential() Create a new PostsynapticPotential, with defaults for the parameters.
PostsynapticPotential(double alpha, double lambda, double mu) Create a new PostsynapticPotential with the specified parameter values.

Method Summary

Modifier and Type	Method and Description
PostsynapticPotential	clone() Return a deep copy of this object.
boolean	equals(java.lang.Object other)
void	fromXML(org.jdom2.Element element) Reads attributes from XML tree.
double	getMaxValue() Return the largest possible function value.
double	getMinValue() Return the smallest possible function value.
double	map(double t) Map a value through the function.
double	mapDerivative(double t) Map a value through the first derivative of this function.
org.jdom2.Element	toXML(org.jdom2.Element element) Writes specific attributes to XML tree.

Methods inherited from class boone.map.Function

create, mapSecondDerivative, setParameters

Methods inherited from class java.lang.Object

finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

PostsynapticPotential

public PostsynapticPotential()

Create a new PostsynapticPotential, with defaults for the parameters. The defaults generate a function that models an excitatory effect for the neuron potential.

PostsynapticPotential

public PostsynapticPotential(double alpha,
                             double lambda,
                             double mu)

Create a new PostsynapticPotential with the specified parameter values. Set lambda < mu to model an excitatory effect for the neuron potential, or lambda > mu for an inhibitory effect.

Parameters:

alpha - Scales the ascending and descending slope, and the maximum, if lambda < mu, or the minimum, if lambda > mu.

lambda - Set lambda < mu to model an excitatory effect for the neuron potential, or lambda > mu for an inhibitory effect.

mu - Set lambda < mu to model an excitatory effect for the neuron potential, or lambda > mu for an inhibitory effect.

Method Detail

map

public double map(double t)

Description copied from class: Function

Map a value through the function.

Overrides:

map in class Function

mapDerivative

public double mapDerivative(double t)

Description copied from class: Function

Map a value through the first derivative of this function.

Overrides:

mapDerivative in class Function

getMinValue

public double getMinValue()

Description copied from class: Function

Return the smallest possible function value. If no exact value can be produced easily, this should return an estimation (lower bound).

Specified by:

getMinValue in class Function

Returns:

the minimum function result.

getMaxValue

public double getMaxValue()

Description copied from class: Function

Return the largest possible function value. If no exact value can be produced easily, this should return an estimation (upper bound).

Specified by:

getMaxValue in class Function

Returns:

the maximum function result.

fromXML

public void fromXML(org.jdom2.Element element)

Description copied from interface: Storable

Reads attributes from XML tree.

Specified by:

fromXML in interface Storable

Overrides:

fromXML in class Function

Parameters:

element - a JDOM element

toXML

public org.jdom2.Element toXML(org.jdom2.Element element)

Writes specific attributes to XML tree.

Specified by:

toXML in interface Storable

Overrides:

toXML in class Function

Parameters:

element - the parent element

Returns:

the function element

clone

public PostsynapticPotential clone()

Description copied from class: Function

Return a deep copy of this object. By default, just calls super.clone().

Overrides:

clone in class Function

equals

public boolean equals(java.lang.Object other)

Overrides:

equals in class java.lang.Object