org.apache.commons.math3.primes
Class Primes

java.lang.Object
  extended by org.apache.commons.math3.primes.Primes

public class Primes
extends Object

Methods related to prime numbers in the range of int:

Since:
3.2
Version:
$Id: Primes.java 1462702 2013-03-30 04:45:52Z psteitz $

Constructor Summary
private Primes()
          Hide utility class.
 
Method Summary
static boolean isPrime(int n)
          Primality test: tells if the argument is a (provable) prime or not.
static int nextPrime(int n)
          Return the smallest prime greater than or equal to n.
static List<Integer> primeFactors(int n)
          Prime factors decomposition
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

Primes

private Primes()
Hide utility class.

Method Detail

isPrime

public static boolean isPrime(int n)
Primality test: tells if the argument is a (provable) prime or not.

It uses the Miller-Rabin probabilistic test in such a way that a result is guaranteed: it uses the firsts prime numbers as successive base (see Handbook of applied cryptography by Menezes, table 4.1).

Parameters:
n - number to test.
Returns:
true if n is prime. (All numbers < 2 return false).

nextPrime

public static int nextPrime(int n)
Return the smallest prime greater than or equal to n.

Parameters:
n - a positive number.
Returns:
the smallest prime greater than or equal to n.
Throws:
MathIllegalArgumentException - if n < 0.

primeFactors

public static List<Integer> primeFactors(int n)
Prime factors decomposition

Parameters:
n - number to factorize: must be ≥ 2
Returns:
list of prime factors of n
Throws:
MathIllegalArgumentException - if n < 2.


Copyright (c) 2003-2013 Apache Software Foundation