Class Trigamma

java.lang.Object
org.apache.commons.numbers.gamma.Trigamma

public final class Trigamma extends Object
Trigamma function. It is the derivative of the digamma function: \( \psi_1(x) = \frac{d^2}{dx^2} (\ln \Gamma(x)) \).
  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    private static final double
    C limit.
    private static final double
    Fraction.
    private static final double
    Fraction.
    private static final double
    Fraction.
    private static final double
    S limit.
  • Constructor Summary

    Constructors
    Modifier
    Constructor
    Description
    private
    Private constructor.
  • 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
  • Field Details

  • Constructor Details

    • Trigamma

      private Trigamma()
      Private constructor.
  • 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.