GammaRatio (Apache Commons Numbers Gamma 1.2 API)

java.lang.Object
- org.apache.commons.numbers.gamma.GammaRatio

```
public final class GammaRatio
extends Object
```
Ratio of Gamma functions.
\[ \frac{\Gamma(a)}{\Gamma(b)} \]
This code has been adapted from:
- The Boost c++ implementation <boost/math/special_functions/gamma.hpp>.
Since:

1.1

See Also:

Boost C++ Ratios of Gamma Functions

Method Summary

All Methods Static Methods Concrete Methods
Modifier and Type	Method	Description
`static double`	`delta(double a, double delta)`	Computes the ratio of gamma functions of a value and an offset value.
`static double`	`value(double a, double b)`	Computes the ratio of gamma functions of two values.

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

- Method Detail
  - value
```
public static double value(double a,
                           double b)
```
    Computes the ratio of gamma functions of two values.
    \[ \frac{\Gamma(a)}{\Gamma(b)} \]
    If either argument is <= 0 or infinite then the result is NaN.
    
    Parameters:
    
    a - Argument a (must be positive finite).
    
    b - Argument b (must be positive finite).
    
    Returns:
    
    \( \Gamma(a) / \Gamma(b) \)
  - delta
```
public static double delta(double a,
                           double delta)
```
    Computes the ratio of gamma functions of a value and an offset value.
    \[ \frac{\Gamma(a)}{\Gamma(a + delta)} \]
    Note that the result is calculated accurately even when delta is small compared to a: indeed even if a+delta ~ a. The function is typically used when a is large and delta is very small.
    
    Parameters:
    
    a - Argument.
    
    delta - Argument.
    
    Returns:
    
    \( \Gamma(a) / \Gamma(a + delta) \)