Package de.tilman_neumann.jml.combinatorics

Class Factorial

java.lang.Object
de.tilman_neumann.jml.combinatorics.Factorial
public class Factorial
extends java.lang.Object
Implementations of the factorial function.

  • Constructor Summary

    Constructors
    Constructor Description
    Factorial()  

  • Method Summary

    Modifier and Type Method Description
    static java.math.BigInteger factorial​(int n)
    Peter Luschny's swinging prime factorial algorithm, see http://luschny.de/math/factorial/SwingIntro.pdf
    static void main​(java.lang.String[] args)
    Test.
    static java.math.BigInteger withStartResult​(int n, int start, java.math.BigInteger startResult)
    Computes the factorial for non-negative integer arguments applying the simple product rule, but allowing for a previously computed start value.

    Methods inherited from class java.lang.Object

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

  • Constructor Details

    • Factorial

      public Factorial()

  • Method Details

    • withStartResult

      public static java.math.BigInteger withStartResult​(int n, int start, java.math.BigInteger startResult) throws java.lang.ArithmeticException
      Computes the factorial for non-negative integer arguments applying the simple product rule, but allowing for a previously computed start value. Adapted from http://www.jonelo.de by Johann Nepomuk Loefflmann (jonelo@jonelo.de), published under GNU General Public License.
      Parameters:
      n - Argument
      start - Argument of the start result
      startResult - Factorial for start
      Returns:
      n! if n is a non-negative integer
      Throws:
      java.lang.ArithmeticException - if n is a negative integer

    • factorial

      public static java.math.BigInteger factorial​(int n) throws java.lang.ArithmeticException
      Peter Luschny's swinging prime factorial algorithm, see http://luschny.de/math/factorial/SwingIntro.pdf
      Parameters:
      n -
      Returns:
      n!
      Throws:
      java.lang.ArithmeticException - if n is a negative integer

    • main

      public static void main​(java.lang.String[] args)
      Test.
      Parameters:
      args - Ignored.