maspack.numerics

Class NewtonRootSolver

java.lang.Object

maspack.numerics.NewtonRootSolver

public class NewtonRootSolver
extends java.lang.Object

Field Summary

Fields

Modifier and Type	Field and Description
static int	MAX_ITER

Constructor Summary

Constructors

Constructor and Description
NewtonRootSolver()

Method Summary

Modifier and Type	Method and Description
static void	clearIterationCount()
static double	findRoot(Diff1Function1x1 fxn, double a, double b, double eps, double feps) Safe implementation of Newton's root-finding, which switchs back to bisection when the Newton's method diverges or doesn't converge fast enough.
static double	findRoot(Diff1Function1x1 fxn, double a, double fa, double b, double fb, double eps, double feps) Safe implementation of Newton's root-finding, which switchs back to bisection when the Newton's method diverges or doesn't converge fast enough.
static int	getIterationCount()

Methods inherited from class java.lang.Object

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

Field Detail

MAX_ITER

public static int MAX_ITER

Constructor Detail

NewtonRootSolver

public NewtonRootSolver()

Method Detail

clearIterationCount

public static void clearIterationCount()

getIterationCount

public static int getIterationCount()

findRoot

public static double findRoot(Diff1Function1x1 fxn,
                              double a,
                              double b,
                              double eps,
                              double feps)

Safe implementation of Newton's root-finding, which switchs back to bisection when the Newton's method diverges or doesn't converge fast enough.

Parameters:

fxn - function to evaluate

a - left-side of interval

b - right-side of interval

eps - absolute interval tolerance for the root

feps - absolute tolerance for function value, such that a root is found if |f(s)| <= feps

Returns:

root

Throws:

NumericalException - if [a,b] does not bracket the root

findRoot

public static double findRoot(Diff1Function1x1 fxn,
                              double a,
                              double fa,
                              double b,
                              double fb,
                              double eps,
                              double feps)

Safe implementation of Newton's root-finding, which switchs back to bisection when the Newton's method diverges or doesn't converge fast enough.

Parameters:

fxn - function to evaluate

a - left-side of interval

fa - function evaluated at a

b - right-side of interval

fb - function evaluated at b

eps - absolute interval tolerance for the root

feps - absolute tolerance for function value, such that a root is found if |f(s)| <= feps

Returns:

root

Throws:

NumericalException - if [a,b] does not bracket the root