Package htsjdk.variant.utils

Class BinomialCoefficientUtil

java.lang.Object
htsjdk.variant.utils.BinomialCoefficientUtil
public class BinomialCoefficientUtil extends Object
A modified version of the Apache Math implementation of binomial coefficient calculation Derived from code within the CombinatoricsUtils and FastMath classes within Commons Math3 (https://commons.apache.org/proper/commons-math/) Included here for use in Genotype Likelihoods calculation, instead of adding Commons Math3 as a dependency Commons Math3 is licensed using the Apache License 2.0 Full text of this license can be found here: https://www.apache.org/licenses/LICENSE-2.0.txt This product includes software developed at The Apache Software Foundation (http://www.apache.org/). This product includes software developed for Orekit by CS Systèmes d'Information (http://www.c-s.fr/) Copyright 2010-2012 CS Systèmes d'Information

  • Constructor Details

    • BinomialCoefficientUtil

      public BinomialCoefficientUtil()

  • Method Details

    • binomialCoefficient

      public static long binomialCoefficient(int n, int k) throws ArithmeticException
      Binomial Coefficient, "n choose k", the number of k-element subsets that can be selected from an n-element set.

      Preconditions:

      • 0 <= k <= n (otherwise IllegalArgumentException is thrown)
      • The result is small enough to fit into a long. The largest value of n for which all coefficients are < Long.MAX_VALUE is 66. If the computed value exceeds Long.MAX_VALUE an ArithmeticException is thrown.

      Parameters:
      n - the size of the set
      k - the size of the subsets to be counted
      Returns:
      n choose k
      Throws:
      ArithmeticException - if n < 0 or k > n or the result is too large to be represented by a long integer.