Package cc.redberry.rings.bigint

Class BigIntegerUtil

java.lang.Object

cc.redberry.rings.bigint.BigIntegerUtil

public final class BigIntegerUtil
extends Object

Since:

1.0

Method Summary

Modifier and Type	Method	Description
static BigInteger	abs(BigInteger a)
static BigInteger	binomial(int n, int k)	Binomial coefficient
static BigInteger	factorial(int number)	Factorial of a number
static BigInteger	gcd(BigInteger[] integers, int from, int to)	Returns the greatest common an array of longs
static BigInteger	gcd(BigInteger a, BigInteger b)
static BigInteger	max(BigInteger a, BigInteger b)
static BigInteger[]	perfectPowerDecomposition(BigInteger n)	Tests whether n is a perfect power n == a^b and returns {a, b} if so and null otherwise
static BigInteger	pow(long base, long exponent)	Returns base in a power of e (non negative)
static BigInteger	pow(BigInteger base, int exponent)	Returns base in a power of e (non negative)
static BigInteger	pow(BigInteger base, long exponent)	Returns base in a power of e (non negative)
static BigInteger	pow(BigInteger base, BigInteger exponent)	Returns base in a power of e (non negative)
static BigInteger	sqrtCeil(BigInteger val)	Returns ceil square root of val
static BigInteger	sqrtFloor(BigInteger val)	Returns floor square root of val

Methods inherited from class java.lang.Object

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

Method Detail

max

public static BigInteger max(BigInteger a,
                             BigInteger b)

abs

public static BigInteger abs(BigInteger a)

gcd

public static BigInteger gcd(BigInteger a,
                             BigInteger b)

gcd

public static BigInteger gcd(BigInteger[] integers,
                             int from,
                             int to)

Returns the greatest common an array of longs

Parameters:

integers - array of longs

from - from position (inclusive)

to - to position (exclusive)

Returns:

greatest common divisor of array

pow

public static BigInteger pow(long base,
                             long exponent)

Returns base in a power of e (non negative)

Parameters:

base - base

exponent - exponent (non negative)

Returns:

base in a power of e

Throws:

ArithmeticException - if the result overflows a long

pow

public static BigInteger pow(BigInteger base,
                             long exponent)

Returns base in a power of e (non negative)

Parameters:

base - base

exponent - exponent (non negative)

Returns:

base in a power of e

Throws:

ArithmeticException - if the result overflows a long

pow

public static BigInteger pow(BigInteger base,
                             int exponent)

Returns base in a power of e (non negative)

Parameters:

base - base

exponent - exponent (non negative)

Returns:

base in a power of e

Throws:

ArithmeticException - if the result overflows a long

pow

public static BigInteger pow(BigInteger base,
                             BigInteger exponent)

Returns base in a power of e (non negative)

Parameters:

base - base

exponent - exponent (non negative)

Returns:

base in a power of e

Throws:

ArithmeticException - if the result overflows a long

sqrtFloor

public static BigInteger sqrtFloor(BigInteger val)
                            throws IllegalArgumentException

Returns floor square root of val

Parameters:

val - the number

Returns:

floor square root

Throws:

IllegalArgumentException

sqrtCeil

public static BigInteger sqrtCeil(BigInteger val)
                           throws IllegalArgumentException

Returns ceil square root of val

Parameters:

val - the number

Returns:

floor square root

Throws:

IllegalArgumentException

perfectPowerDecomposition

public static BigInteger[] perfectPowerDecomposition(BigInteger n)

Tests whether n is a perfect power n == a^b and returns {a, b} if so and null otherwise

Parameters:

n - the number

Returns:

array {a, b} so that n = a^b or null is n is not a perfect power

factorial

public static BigInteger factorial(int number)

Factorial of a number

binomial

public static BigInteger binomial(int n,
                                  int k)

Binomial coefficient