ContinuedFraction (Apache Commons Math 3.5 API)

java.lang.Object
- org.apache.commons.math3.util.ContinuedFraction

```
public abstract class ContinuedFraction
extends Object
```
Provides a generic means to evaluate continued fractions. Subclasses simply provided the a and b coefficients to evaluate the continued fraction.
References:
- Continued Fraction

Constructor Summary

Constructors
Modifier Constructor and Description

protected ContinuedFraction()
Default constructor.

Constructors
Modifier	Constructor and Description
`protected`	`ContinuedFraction()` Default constructor.

Method Summary

Methods
Modifier and Type	Method and Description
`double`	`evaluate(double x)` Evaluates the continued fraction at the value x.
`double`	`evaluate(double x, double epsilon)` Evaluates the continued fraction at the value x.
`double`	`evaluate(double x, double epsilon, int maxIterations)` Evaluates the continued fraction at the value x.
`double`	`evaluate(double x, int maxIterations)` Evaluates the continued fraction at the value x.
`protected abstract double`	`getA(int n, double x)` Access the n-th a coefficient of the continued fraction.
`protected abstract double`	`getB(int n, double x)` Access the n-th b coefficient of the continued fraction.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - ContinuedFraction
```
protected ContinuedFraction()
```
    Default constructor.
- Method Detail
  - getA
```
protected abstract double getA(int n,
          double x)
```
    Access the n-th a coefficient of the continued fraction. Since a can be a function of the evaluation point, x, that is passed in as well.
    
    Parameters:
    n - the coefficient index to retrieve.
    x - the evaluation point.
    
    Returns:
    the n-th a coefficient.
  - getB
```
protected abstract double getB(int n,
          double x)
```
    Access the n-th b coefficient of the continued fraction. Since b can be a function of the evaluation point, x, that is passed in as well.
    
    Parameters:
    n - the coefficient index to retrieve.
    x - the evaluation point.
    
    Returns:
    the n-th b coefficient.
  - evaluate
```
public double evaluate(double x)
                throws ConvergenceException
```
    Evaluates the continued fraction at the value x.
    
    Parameters:
    x - the evaluation point.
    
    Returns:
    the value of the continued fraction evaluated at x.
    
    Throws:
    
    ConvergenceException - if the algorithm fails to converge.
  - evaluate
```
public double evaluate(double x,
              double epsilon)
                throws ConvergenceException
```
    Evaluates the continued fraction at the value x.
    
    Parameters:
    x - the evaluation point.
    epsilon - maximum error allowed.
    
    Returns:
    the value of the continued fraction evaluated at x.
    
    Throws:
    
    ConvergenceException - if the algorithm fails to converge.
  - evaluate
```
public double evaluate(double x,
              int maxIterations)
                throws ConvergenceException,
                       MaxCountExceededException
```
    Evaluates the continued fraction at the value x.
    
    Parameters:
    x - the evaluation point.
    maxIterations - maximum number of convergents
    
    Returns:
    the value of the continued fraction evaluated at x.
    
    Throws:
    
    ConvergenceException - if the algorithm fails to converge.
    
    MaxCountExceededException - if maximal number of iterations is reached
  - evaluate
```
public double evaluate(double x,
              double epsilon,
              int maxIterations)
                throws ConvergenceException,
                       MaxCountExceededException
```
    Evaluates the continued fraction at the value x.
    The implementation of this method is based on the modified Lentz algorithm as described on page 18 ff. in:
    - I. J. Thompson, A. R. Barnett. "Coulomb and Bessel Functions of Complex Arguments and Order." http://www.fresco.org.uk/papers/Thompson-JCP64p490.pdf
    Note: the implementation uses the terms a_i and b_i as defined in Continued Fraction @ MathWorld.
    Parameters:
    x - the evaluation point.
    epsilon - maximum error allowed.
    maxIterations - maximum number of convergents
    
    Returns:
    the value of the continued fraction evaluated at x.
    
    Throws:
    
    ConvergenceException - if the algorithm fails to converge.
    
    MaxCountExceededException - if maximal number of iterations is reached

Class ContinuedFraction

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

ContinuedFraction

Method Detail

getA

getB

evaluate

evaluate

evaluate

evaluate