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Beta Class

Beta functions.
Inheritance Hierarchy
SystemObject
  Accord.MathBeta

Namespace:  Accord.Math
Assembly:  Accord.Math (in Accord.Math.dll) Version: 3.8.0
Syntax
public static class Beta
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The Beta type exposes the following members.

Methods
  NameDescription
Public methodStatic memberCode exampleFunction
Beta function as gamma(a) * gamma(b) / gamma(a+b).
Public methodStatic memberCode exampleIncbcf
Continued fraction expansion #1 for incomplete beta integral.
Public methodStatic memberCode exampleIncbd
Continued fraction expansion #2 for incomplete beta integral.
Public methodStatic memberCode exampleIncomplete
Incomplete (regularized) Beta function Ix(a, b).
Public methodStatic memberCode exampleIncompleteInverse
Inverse of incomplete beta integral.
Public methodStatic memberCode exampleLog
Natural logarithm of the Beta function.
Public methodStatic memberCode exampleMultinomial
Multinomial Beta function.
Public methodStatic memberCode examplePowerSeries
Power series for incomplete beta integral. Use when b*x is small and x not too close to 1.
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Remarks

This class offers implementations for the many Beta functions, such as the Beta function itself, its logarithm, the Incomplete(Double, Double, Double) incomplete regularized functions and others

The beta function was studied by Euler and Legendre and was given its name by Jacques Binet; its symbol Β is a Greek capital β rather than the similar Latin capital B.

References:

  • Cephes Math Library, http://www.netlib.org/cephes/
  • Wikipedia contributors, "Beta function,". Wikipedia, The Free Encyclopedia. Available at: http://en.wikipedia.org/wiki/Beta_function

Examples
Beta.Function(4, 0.42);       // 1.2155480852832423
Beta.Log(4, 15.2);            // -9.46087817876467
Beta.Incbcf(4, 2, 4.2);       // -0.23046874999999992
Beta.Incbd(4, 2, 4.2);        // 0.7375
Beta.PowerSeries(4, 2, 4.2);  // -3671.801280000001

Beta.Incomplete(a: 5, b: 4, x: 0.5);   // 0.36328125
Beta.IncompleteInverse(0.5, 0.6, 0.1); // 0.019145979066925722
Beta.Multinomial(0.42, 0.5, 5.2 );     // 0.82641912952987062
See Also