becker.xtras.grapher
Class SamplePolynomialFunction

java.lang.Object
  becker.xtras.grapher.SamplePolynomialFunction

All Implemented Interfaces:

IPolynomialFunction

public final class SamplePolynomialFunction
extends Object
implements IPolynomialFunction

A sample class implementing the IPolynomialFunction interface. It calculates values of a polynomial function.

Please see the package description for a more in-depth discussion of using this class.

Author:

Byron Weber Becker

Constructor Summary

SamplePolynomialFunction(int deg)
Create a sample polynomial function with the given degree.

Method Summary

void	addView(IView aView) Add a view (graphical user interface) to the function.
double	eval(double x) Evaluate the function for a given value of x.
double[]	getCoefficients() Get the coefficients for this polynomial.
int	getDegree() Get the degree of this polynomial.
double[]	getYValues(double minX, double maxX, int num) Get evenly distributed values for f(x) for all the values of x between minX and maxX.
void	setCoefficients(double[] coefs) Set the coefficients for this polynomial.

Methods inherited from class java.lang.Object

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

Constructor Detail

SamplePolynomialFunction

public SamplePolynomialFunction(int deg)

Create a sample polynomial function with the given degree.

Parameters:

deg - The degree of the leading term in the polynomial.

Method Detail

eval

public double eval(double x)

Description copied from interface: IPolynomialFunction

Evaluate the function for a given value of x.

Specified by:

eval in interface IPolynomialFunction

Parameters:

x - The value for which the function should be evaluated.

getDegree

public int getDegree()

Description copied from interface: IPolynomialFunction

Get the degree of this polynomial. The degree is the value of the largest exponent of x. For example, the degree of y = 5*x^3 + 2*x^2 + 0*x + 5 is 3.

Specified by:

getDegree in interface IPolynomialFunction

Returns:

the degree of this polynomial.

setCoefficients

public void setCoefficients(double[] coefs)

Description copied from interface: IPolynomialFunction

Set the coefficients for this polynomial. The length of the array of coefficients must be equal to the degree + 1.

Specified by:

setCoefficients in interface IPolynomialFunction

Parameters:

coefs - the coefficients to the polynomial such that aⁱ appears in coef[i].

getCoefficients

public double[] getCoefficients()

Description copied from interface: IPolynomialFunction

Get the coefficients for this polynomial. The length of the array of coefficients must be equal to the degree + 1.

Specified by:

getCoefficients in interface IPolynomialFunction

Returns:

the coefficients to the polynomial such that aⁱ appears in thei^th position in the array.

getYValues

public double[] getYValues(double minX,
                           double maxX,
                           int num)

Description copied from interface: IPolynomialFunction

Get evenly distributed values for f(x) for all the values of x between minX and maxX.

Specified by:

getYValues in interface IPolynomialFunction

Parameters:

minX - The smallest value of x; must be less than maxX.

maxX - The largest value of x.

num - The number of values to return; must be positive.

Returns:

return an array with f(minX+0*deltaX), f(minX+1*deltaX), f(minX+2*deltaX), ..., f(minX*numVals*deltaX = maxX)

addView

public void addView(IView aView)

Description copied from interface: IPolynomialFunction

Add a view (graphical user interface) to the function. The view's updateView method must be called each time the function's state changes.

Specified by:

addView in interface IPolynomialFunction