org.apache.commons.math.optimization.fitting

Class GaussianDerivativeFunction

java.lang.Object

org.apache.commons.math.optimization.fitting.GaussianDerivativeFunction

All Implemented Interfaces:

java.io.Serializable, UnivariateRealFunction

public class GaussianDerivativeFunction
extends java.lang.Object
implements UnivariateRealFunction, java.io.Serializable

The derivative of GaussianFunction. Specifically:

f'(x) = (-b / (d^2)) * (x - c) * exp(-((x - c)^2) / (2*(d^2)))

Notation key:

• x^n: x raised to the power of n
• exp(x): e^x

Since:

2.2

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
GaussianDerivativeFunction(double[] parameters) Constructs an instance with the specified parameters.
GaussianDerivativeFunction(double b, double c, double d) Constructs an instance with the specified parameters.

Method Summary

Modifier and Type	Method and Description
double	value(double x) Compute the value for the function.

Methods inherited from class java.lang.Object

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

Constructor Detail

GaussianDerivativeFunction

public GaussianDerivativeFunction(double b,
                                  double c,
                                  double d)

Constructs an instance with the specified parameters.

Parameters:

b - b parameter value

c - c parameter value

d - d parameter value

Throws:

java.lang.IllegalArgumentException - if d is 0

GaussianDerivativeFunction

public GaussianDerivativeFunction(double[] parameters)

Constructs an instance with the specified parameters.

Parameters:

parameters - b, c, and d parameter values

Throws:

java.lang.IllegalArgumentException - if parameters is null, parameters length is not 3, or if parameters[2] is 0

Method Detail

value

public double value(double x)

Compute the value for the function.

Specified by:

value in interface UnivariateRealFunction

Parameters:

x - the point for which the function value should be computed

Returns:

the value