Package org.apache.commons.numbers.gamma

Class Trigamma

java.lang.Object
org.apache.commons.numbers.gamma.Trigamma
public class Trigamma
extends java.lang.Object
Trigamma function. It is the derivative of the digamma function: \( \psi_1(x) = \frac{d^2}{dx^2} (\ln \Gamma(x)) \).

  • Constructor Summary

    Constructors 
    Constructor Description
    Trigamma()  

  • Method Summary

    Modifier and Type Method Description
    static double value​(double x)
    Computes the trigamma function.

    Methods inherited from class java.lang.Object

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

  • Constructor Details

  • Method Details

    • value

      public static double value​(double x)
      Computes the trigamma function.
      Parameters:
      x - Argument.
      Returns:
      trigamma(x) to within 1e-8 relative or absolute error whichever is larger.