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

java.lang.Object
  extended by org.apache.commons.math.optimization.fitting.GaussianDerivativeFunction
All Implemented Interfaces:
Serializable, UnivariateRealFunction

public class GaussianDerivativeFunction
extends Object
implements UnivariateRealFunction, Serializable

The derivative of GaussianFunction. Specifically:

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

Notation key:

Since:
2.2
Version:
$Revision: 1037327 $ $Date: 2010-11-20 21:57:37 +0100 (sam. 20 nov. 2010) $
See Also:
Serialized Form

Field Summary
private  double b
          Parameter b of this function.
private  double c
          Parameter c of this function.
private  double d2
          Square of the parameter d of this function.
private static long serialVersionUID
          Serializable version identifier.
 
Constructor Summary
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
 double value(double x)
          Compute the value for the function.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Field Detail

serialVersionUID

private static final long serialVersionUID
Serializable version identifier.

See Also:
Constant Field Values

b

private final double b
Parameter b of this function.


c

private final double c
Parameter c of this function.


d2

private final double d2
Square of the parameter d of this function.

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:
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:
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


Copyright (c) 2003-2011 Apache Software Foundation