Package io.mosip.kernel.core.util

Class MathUtils

java.lang.Object

io.mosip.kernel.core.util.MathUtils

public final class MathUtils
extends Object

Utilities for Mathematical operations.

Since:

1.0.0

Author:

Ritesh Sinha

Method Summary

Modifier and Type	Method	Description
static double	ceil(double num)	Get the smallest whole number larger than number.
static double	floor(double num)	Get the largest whole number smaller than number.
static double	getAbs(double num)	Absolute value.
static float	getAbs(float num)	Absolute value.
static int	getAbs(int num)	Absolute value.
static long	getAbs(long num)	Absolute value.
static double	getArrayMaxValue(double[] arr)	Returns the maximum of the entries in the input array, or Double.NaN if the array is empty.
static double	getArrayMaxValue(double[] arr, int startindex, int length)	Returns the maximum of the entries in the specified portion of the input array, or Double.NaN if the designated subarray is empty
static double	getArrayMinValue(double[] arr)	Returns the minimum of the entries in the input array, or Double.NaN if the array is empty.
static double	getArrayMinValue(double[] arr, int startindex, int length)	Returns the minimum of the entries in the specified portion of the input array, or Double.NaN if the designated subarray is empty.
static double	getArrayValuesMean(double[] arr)	Returns the arithmetic mean of the entries in the input array, or Double.NaN if the array is empty.
static double	getArrayValuesMean(double[] arr, int startindex, int length)
static double	getArrayValuesProduct(double[] arr)	Returns the product of the entries in the input array, or Double.NaN if the array is empty.
static double	getArrayValuesProduct(double[] arr, int startindex, int length)	Returns the product of the entries in the specified portion of the input array, or Double.NaN if the designated subarray is empty.
static double	getArrayValuesSum(double[] arr)	Returns the sum of the values in the input array, or Double.NaN if the array is empty.
static double	getArrayValuesSum(double[] arr, int startindex, int length)	Returns the sum of the entries in the specified portion of the input array, or Double.NaN if the designated subarray is empty.
static double[]	getCopyOfArray(double[] source)	Creates a copy of source array
static double[]	getCopyOfArray(double[] source, int length)	Creates a copy of source array
static int[]	getCopyOfArray(int[] source)	Creates a copy of source array
static int[]	getCopyOfArray(int[] source, int length)	Creates a copy of source array.
static long	getFactorial(int number)	Evaluate Factorial
static int	getGcd(int firstnumber, int secondnumber)	Computes the greatest common divisor of the absolute value of two numbers, using a modified version of the "binary gcd" method.
static long	getGcd(long firstnumber, long secondnumber)	Gets the greatest common divisor of the absolute value of two numbers, using the "binary gcd" method which avoids division and modulo operations
static double	getLog(double num)	Natural logarithm.
static double	getLog10(double num)	Compute the base 10 logarithm.
static double	getMax(double firstnumber, double secondnumber)	Compute the maximum of two values
static int	getMax(int firstnumber, int secondnumber)	Compute the maximum of two values
static double	getPow(double num, double exp)	Power function.
static int	getPow(int num, int exp)	Raise an int to an int power.
static long	getPow(long num, int exp)	Raise a long to an int power.
static BigInteger	getPow(BigInteger num, int exp)
static BigInteger	getPow(BigInteger num, BigInteger exp)	Raise a BigInteger to a BigInteger power.
static List<Integer>	getPrimeFactors(int num)	Prime factors decomposition
static double	getRandom(double lowerlimit, double upperlimit)	Generate random number
static float	getRandom(float lowerlimit, float upperlimit)	Generate random number
static int	getRandom(int lowerlimit, int upperlimit)	Generate random number
static long	getRandom(long lowerlimit, long upperlimit)	Generate random number
static long	getRound(double num)	Get the closest long to num.
static double	getRound(double num, int place)	Rounds the given value to the specified number of decimal places.
static float	getRound(float num, int place)	Rounds the given value to the specified number of decimal places.
static double	getSqrt(double num)	Compute the square root of a number.
static boolean	isPrimeOrNot(int num)	Primality test: tells if the argument is a (provable) prime or not.
static int	nextPrimeNumber(int num)	Return the smallest prime greater than or equal to n.

Methods inherited from class java.lang.Object

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

Method Detail

getPow

public static int getPow(int num,
                         int exp)

Raise an int to an int power.

Parameters:

num - Number to raise.

exp - exponent (must be positive or zero)

Returns:

num^exp

Throws:

NotPositiveException - if exp is less than 0.

ArithmeticException - if the result would overflow.

getPow

public static double getPow(double num,
                            double exp)

Power function. Compute num^exp.

Parameters:

num - a double

exp - a double

Returns:

double

getPow

public static long getPow(long num,
                          int exp)

Raise a long to an int power.

Parameters:

num - Number to raise.

exp - Exponent (must be positive or zero).

Returns:

num^exp

Throws:

NotPositiveException - if exp is less than 0.

ArithmeticException - if the result would overflow.

getPow

public static BigInteger getPow(BigInteger num,
                                int exp)

Parameters:

num - Number to raise.

exp - Exponent (must be positive or zero).

Returns:

num^exp

Throws:

NotPositiveException - if exp is less than 0.

getPow

public static BigInteger getPow(BigInteger num,
                                BigInteger exp)

Raise a BigInteger to a BigInteger power.

Parameters:

num - Number to raise.

exp - Exponent (must be positive or zero).

Returns:

num^exp

Throws:

NotPositiveException - if exp is less than 0.

getRandom

public static int getRandom(int lowerlimit,
                            int upperlimit)

Generate random number

Parameters:

lowerlimit - starting value

upperlimit - maximum value

Returns:

random number between lowerlimit and upperlimit.

Throws:

NumberIsTooLargeException - -if lower is greater than or equal to upper

getRandom

public static long getRandom(long lowerlimit,
                             long upperlimit)

Generate random number

Parameters:

lowerlimit - starting value

upperlimit - maximum value

Returns:

random number between lowerlimit and upperlimit.

Throws:

NumberIsTooLargeException - -if lower is greater than or equal to upper

getRandom

public static double getRandom(double lowerlimit,
                               double upperlimit)

Generate random number

Parameters:

lowerlimit - starting value

upperlimit - maximum value

Returns:

random number between lowerlimit and upperlimit

Throws:

NumberIsTooLargeException - -if lower is greater than or equal to upper

NotFiniteNumberException - if one of the bounds is infinite

NotANumberException - if one of the bounds is NaN

getRandom

public static float getRandom(float lowerlimit,
                              float upperlimit)

Generate random number

Parameters:

lowerlimit - starting value

upperlimit - maximum value

Returns:

random number between lowerlimit and upperlimit

getSqrt

public static final double getSqrt(double num)

Compute the square root of a number.

Parameters:

num - number on which evaluation is done

Returns:

square root of num.

getMax

public static final int getMax(int firstnumber,
                               int secondnumber)

Compute the maximum of two values

Parameters:

firstnumber - first value

secondnumber - second value

Returns:

secondnumber if firstnumber is lesser or equal to secondnumber, firstnumber otherwise

getMax

public static final double getMax(double firstnumber,
                                  double secondnumber)

Compute the maximum of two values

Parameters:

firstnumber - first value

secondnumber - second value

Returns:

secondnumber if firstnumber is lesser or equal to secondnumber, firstnumber otherwise

getRound

public static final double getRound(double num,
                                    int place)

Rounds the given value to the specified number of decimal places.

Parameters:

num - Value to round.

place - Number of digits to the right of the decimal point.

Returns:

the rounded value.

getRound

public static final float getRound(float num,
                                   int place)

Rounds the given value to the specified number of decimal places.

Parameters:

num - Value to round.

place - Number of digits to the right of the decimal point.

Returns:

the rounded value.

getRound

public static final long getRound(double num)

Get the closest long to num.

Parameters:

num - number from which closest long is requested

Returns:

closest long to num

getAbs

public static final double getAbs(double num)

Absolute value.

Parameters:

num - number from which absolute value is requested.

Returns:

abs(num)

getAbs

public static final float getAbs(float num)

Absolute value.

Parameters:

num - number from which absolute value is requested.

Returns:

abs(num)

getAbs

public static final long getAbs(long num)

Absolute value.

Parameters:

num - number from which absolute value is requested.

Returns:

abs(num)

getAbs

public static final int getAbs(int num)

Absolute value.

Parameters:

num - number from which absolute value is requested.

Returns:

abs(num)

getFactorial

public static final long getFactorial(int number)

Evaluate Factorial

Parameters:

number - argument

Returns:

n!

Throws:

NotPositiveException - -If number is not positive

ArithmeticException - -If number is greator than 20 and result is too large to fit in long type.

getGcd

public static final int getGcd(int firstnumber,
                               int secondnumber)

Computes the greatest common divisor of the absolute value of two numbers, using a modified version of the "binary gcd" method.

Parameters:

firstnumber - Number.

secondnumber - Number.

Returns:

the greatest common divisor (never negative).

Throws:

ArithmeticException - if the result cannot be represented as a non-negative integer value.

getGcd

public static final long getGcd(long firstnumber,
                                long secondnumber)

Gets the greatest common divisor of the absolute value of two numbers, using the "binary gcd" method which avoids division and modulo operations

Parameters:

firstnumber - Number.

secondnumber - Number.

Returns:

the greatest common divisor, never negative.

Throws:

ArithmeticException - if the result cannot be represented as a non-negative long type value.

getLog

public static final double getLog(double num)

Natural logarithm.

Parameters:

num - a double

Returns:

log(x)

getLog10

public static final double getLog10(double num)

Compute the base 10 logarithm.

Parameters:

num - a number

Returns:

log10(x)

getCopyOfArray

public static int[] getCopyOfArray(int[] source)

Creates a copy of source array

Parameters:

source - Array to be copied.

Returns:

the copied array.

getCopyOfArray

public static int[] getCopyOfArray(int[] source,
                                   int length)

Creates a copy of source array.

Parameters:

source - Array to be copied.

length - Number of entries to copy. If smaller then the source length, the copy will be truncated, if larger it will padded with zeroes.

Returns:

the copied array.

getCopyOfArray

public static double[] getCopyOfArray(double[] source)

Creates a copy of source array

Parameters:

source - Array to be copied.

Returns:

the copied array.

getCopyOfArray

public static double[] getCopyOfArray(double[] source,
                                      int length)

Creates a copy of source array

Parameters:

source - Array to be copied.

length - Number of entries to copy. If smaller then the source length, the copy will be truncated, if larger it will padded with zeroes.

Returns:

the copied array.

getArrayMaxValue

public static double getArrayMaxValue(double[] arr)

Returns the maximum of the entries in the input array, or Double.NaN if the array is empty.

Parameters:

arr - the input array

Returns:

the maximum of the values or Double.NaN if the array is empty

Throws:

IllegalArgumentException - if the array is null

getArrayMaxValue

public static double getArrayMaxValue(double[] arr,
                                      int startindex,
                                      int length)

Returns the maximum of the entries in the specified portion of the input array, or Double.NaN if the designated subarray is empty

Parameters:

arr - the input array

startindex - index of the first array element to include

length - the number of elements to include

Returns:

the maximum of the values or Double.NaN if length = 0

Throws:

IllegalArgumentException - if the array is null or the array index parameters are not valid

getArrayMinValue

public static double getArrayMinValue(double[] arr)

Returns the minimum of the entries in the input array, or Double.NaN if the array is empty.

Parameters:

arr - the input array

Returns:

the minimum of the values or Double.NaN if the array is empty

Throws:

IllegalArgumentException - if the array is null

getArrayMinValue

public static double getArrayMinValue(double[] arr,
                                      int startindex,
                                      int length)

Returns the minimum of the entries in the specified portion of the input array, or Double.NaN if the designated subarray is empty.

Parameters:

arr - the input array

startindex - index of the first array element to include

length - the number of elements to include

Returns:

the minimum of the values or Double.NaN if length = 0

Throws:

IllegalArgumentException - if the array is null or the array index parameters are not valid

getArrayValuesSum

public static double getArrayValuesSum(double[] arr)

Returns the sum of the values in the input array, or Double.NaN if the array is empty.

Parameters:

arr - array of values to sum

Returns:

the sum of the values or Double.NaN if the array is empty

Throws:

IllegalArgumentException - if the array is null

getArrayValuesSum

public static double getArrayValuesSum(double[] arr,
                                       int startindex,
                                       int length)

Returns the sum of the entries in the specified portion of the input array, or Double.NaN if the designated subarray is empty.

Parameters:

arr - the input array

startindex - index of the first array element to include

length - the number of elements to include

Returns:

the sum of the values or Double.NaN if length = 0

Throws:

IllegalArgumentException - if the array is null or the array index parameters are not valid

getArrayValuesProduct

public static double getArrayValuesProduct(double[] arr)

Returns the product of the entries in the input array, or Double.NaN if the array is empty.

Parameters:

arr - the input array

Returns:

the product of the values or Double.NaN if the array is empty

Throws:

IllegalArgumentException - if the array is null

getArrayValuesProduct

public static double getArrayValuesProduct(double[] arr,
                                           int startindex,
                                           int length)

Returns the product of the entries in the specified portion of the input array, or Double.NaN if the designated subarray is empty.

Parameters:

arr - the input array

startindex - index of the first array element to include

length - the number of elements to include

Returns:

the product of the values or Double.NaN if length = 0

Throws:

IllegalArgumentException - if the array is null or the array index parameters are not valid

getArrayValuesMean

public static double getArrayValuesMean(double[] arr)

Returns the arithmetic mean of the entries in the input array, or Double.NaN if the array is empty.

Parameters:

arr - the input array

Returns:

the mean of the values or Double.NaN if the array is empty

Throws:

IllegalArgumentException - if the array is null

getArrayValuesMean

public static double getArrayValuesMean(double[] arr,
                                        int startindex,
                                        int length)

Parameters:

arr - the input array

startindex - index of the first array element to include

length - the number of elements to include

Returns:

the mean of the values or Double.NaN if length = 0

Throws:

IllegalArgumentException - if the array is null or the array index parameters are not valid

isPrimeOrNot

public static boolean isPrimeOrNot(int num)

Primality test: tells if the argument is a (provable) prime or not.

Parameters:

num - number to test.

Returns:

true if num is prime.

nextPrimeNumber

public static int nextPrimeNumber(int num)

Return the smallest prime greater than or equal to n.

Parameters:

num - a positive number.

Returns:

the smallest prime greater than or equal to n.

Throws:

IllegalArgumentException - if num is less than 0.

getPrimeFactors

public static List<Integer> getPrimeFactors(int num)

Prime factors decomposition

Parameters:

num - number to factorize: must be ≥ 2

Returns:

list of prime factors of num

Throws:

IllegalArgumentException - if num is less than 2.

ceil

public static double ceil(double num)

Get the smallest whole number larger than number.

Parameters:

num - number from which ceil is requested

Returns:

a double number c such that c is an integer is greator than equal to num and num is greator than c-1.0

floor

public static double floor(double num)

Get the largest whole number smaller than number.

Parameters:

num - number from which floor is requested

Returns:

a double number f such that f is an integer f is less than or equal to num and num is less than f + 1.0