IncompleteBetaFunction (OpenGamma Strata)

java.lang.Object
- com.opengamma.strata.math.impl.function.special.IncompleteBetaFunction

All Implemented Interfaces:

Function<Double,Double>
```
public class IncompleteBetaFunction
extends Object
implements Function<Double,Double>
```
The incomplete beta function is defined as: $$ \begin{equation*} I_x(a, b)=\frac{B_x(a, b)}{B(a, b)}\int_0^x t^{a-1}(1-t)^{b-1}dt \end{equation*} $$ where $a,b>0$.
This class uses the Commons Math library implementation of the Beta function.

Constructor Summary

Constructors
Constructor	Description
`IncompleteBetaFunction(double a, double b)`	Creates an instance using the default values for the accuracy (`10^-12`) and number of iterations (`10000`).
`IncompleteBetaFunction(double a, double b, double eps, int maxIter)`	Creates an instance.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type Method Description

Double apply(Double x)
Evaluates the function.
- Methods inherited from class java.lang.Object
  clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
- Methods inherited from interface java.util.function.Function
  andThen, compose

- Constructor Detail
  - IncompleteBetaFunction
```
public IncompleteBetaFunction(double a,
                              double b)
```
    Creates an instance using the default values for the accuracy (10^-12) and number of iterations (10000).
    
    Parameters:
    
    a - a, $a > 0$
    
    b - b, $b > 0$
  - IncompleteBetaFunction
```
public IncompleteBetaFunction(double a,
                              double b,
                              double eps,
                              int maxIter)
```
    Creates an instance.
    
    Parameters:
    
    a - a, $a > 0$
    
    b - b, $b > 0$
    
    eps - approximation accuracy, $\epsilon \geq 0$
    
    maxIter - maximum number of iterations, $\iter \geq 1$
- Method Detail
  - apply
```
public Double apply(Double x)
```
    Evaluates the function.
    
    Specified by:
    
    apply in interface Function<Double,Double>
    
    Parameters:
    
    x - x
    
    Returns:
    
    the value of the function
    
    Throws:
    
    IllegalArgumentException - if $x < 0$ or $x > 1$