umontreal.iro.lecuyer.functions

Class PowerMathFunction

java.lang.Object

umontreal.iro.lecuyer.functions.PowerMathFunction

All Implemented Interfaces:

MathFunction, MathFunctionWithFirstDerivative

public class PowerMathFunction
extends java.lang.Object
implements MathFunction, MathFunctionWithFirstDerivative

Represents a function computing (af (x) + b)^p for a user-defined function f (x) and power p.

Constructor Summary

Constructors

Constructor and Description
PowerMathFunction(MathFunction func, double power) Constructs a new power function for function func and power power.
PowerMathFunction(MathFunction func, double a, double b, double power) Constructs a new power function for function func, power power, and constants a and b.

Method Summary

Modifier and Type	Method and Description
double	derivative(double x) Computes (or estimates) the first derivative of the function at point x.
double	evaluate(double x) Returns the value of the function evaluated at x.
double	getA() Returns the value of a.
double	getB() Returns the value of b.
MathFunction	getFunction() Returns the function f (x).
double	getPower() Returns the power p.

Methods inherited from class java.lang.Object

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

Constructor Detail

PowerMathFunction

public PowerMathFunction(MathFunction func,
                         double power)

Constructs a new power function for function func and power power. The values of the constants are a = 1 and b = 0.

Parameters:

func - the function f (x).

power - the power p.

PowerMathFunction

public PowerMathFunction(MathFunction func,
                         double a,
                         double b,
                         double power)

Constructs a new power function for function func, power power, and constants a and b.

Parameters:

func - the function f (x).

power - the power p.

a - the multiplicative constant.

b - the additive constant.

Method Detail

getFunction

public MathFunction getFunction()

Returns the function f (x).

Returns:

the function.

getA

public double getA()

Returns the value of a.

Returns:

the value of a.

getB

public double getB()

Returns the value of b.

Returns:

the value of b.

getPower

public double getPower()

Returns the power p.

Returns:

the power.

derivative

public double derivative(double x)

Description copied from interface: MathFunctionWithFirstDerivative

Computes (or estimates) the first derivative of the function at point x.

Specified by:

derivative in interface MathFunctionWithFirstDerivative

Parameters:

x - the point to evaluate the derivative to.

Returns:

the value of the derivative.

evaluate

public double evaluate(double x)

Description copied from interface: MathFunction

Returns the value of the function evaluated at x.

Specified by:

evaluate in interface MathFunction

Parameters:

x - value at which the distribution function is evaluated

Returns:

function evaluated at x