jhelp.util.math

Class UtilMath

java.lang.Object

jhelp.util.math.UtilMath

public final class UtilMath
extends java.lang.Object

Utilities for math.
It complete the Math class

Author:

JHelp

Field Summary

Fields

Modifier and Type	Field and Description
static double	EPSILON Epsilon
static double	PI_2 PI / 2
static double	TWO_PI 2 * PI

Constructor Summary

Constructors

Modifier	Constructor and Description
private	UtilMath() To avoid instance

Method Summary

Methods

Modifier and Type	Method and Description
static double	Bernouilli(int n, int m, double t) Compute the Bernouilli value
static long	C(int n, int m) Compute the combination of N elements in M
static boolean	equals(double real1, double real2) Indicates if 2 double are equal
static long	factorial(int integer) Compute the factorial of an integer
static int	greaterCommonDivisor(int integer1, int integer2) Compute the Greater Common Divisor of two integers.
static double	interpolationExponential(double t) Compute exponential interpolation.
static double	interpolationLogarithm(double t) Compute logarithm interpolation.
static double	interpolationSinus(double t) Compute sinus interpolation.
static boolean	isNul(double real) Indicates if a double is zero
static int	limit0_255(int integer) Return the given integer, if the integer is in [0, 255].
static int	lowerCommonMultiple(int integer1, int integer2) Compute the Lower Common Multiple of two integers.
static double	max(double... doubles) Maximum of several double
static int	maxIntegers(int... integers) Maximum of several integers
static double	min(double... doubles) Minimum of several double
static int	minIntegers(int... integers) Minimum of several integers
static double	modulo(double real, double modulo) Compute the modulo of a real
static int	modulo(int integer, int modulo) Mathematical modulo.
static long	modulo(long integer, long modulo) Mathematical modulo.
static double	moduloInterval(double real, double min, double max) Modulate a real inside an interval
static double	PCubique(double cp, double p1, double p2, double p3, double t) Compute the cubic interpolation
static double[]	PCubiques(double cp, double p1, double p2, double p3, int precision, double[] cub) Compute several cubic interpolation
static long	pow(long integer, long pow) Power of integer, more fast than Math.pow(double, double) for some case.
static double	PQuadrique(double cp, double p1, double p2, double t) Compute the quadric interpolation
static double[]	PQuadriques(double cp, double p1, double p2, int precision, double[] quad) Compute several quadric interpolation
static int	sign(double real) Sign of a double.
static int	sign(int integer) Sign of an integer.
static int	sign(long integer) Sign of an integer.

Methods inherited from class java.lang.Object

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

Field Detail

EPSILON

public static final double EPSILON

Epsilon

PI_2

public static double PI_2

PI / 2

TWO_PI

public static double TWO_PI

2 * PI

Constructor Detail

UtilMath

private UtilMath()

To avoid instance

Method Detail

Bernouilli

public static double Bernouilli(int n,
                int m,
                double t)

Compute the Bernouilli value

Parameters:

n - Number of elements

m - Total of elements

t - Factor in [0, 1]

Returns:

Bernouilli value

C

public static long C(int n,
     int m)

Compute the combination of N elements in M

Parameters:

n - Number of elements

m - Total of elements

Returns:

The combination of N elements in M

equals

public static boolean equals(double real1,
             double real2)

Indicates if 2 double are equal

Parameters:

real1 - First double

real2 - Second double

Returns:

true if equals

factorial

public static long factorial(int integer)

Compute the factorial of an integer

Parameters:

integer - Integer to have is factorial

Returns:

integer!

greaterCommonDivisor

public static int greaterCommonDivisor(int integer1,
                       int integer2)

Compute the Greater Common Divisor of two integers.
If both integers are 0, 0 is return

Parameters:

integer1 - First integer

integer2 - Second integer

Returns:

GCD

interpolationExponential

public static double interpolationExponential(double t)

Compute exponential interpolation.
f : [0, 1] -> [0, 1]
f(0)=0
f(1)=1
f is strictly increase

Parameters:

t - Value to interpolate in [0, 1]

Returns:

Interpolated result in [0, 1]

interpolationLogarithm

public static double interpolationLogarithm(double t)

Compute logarithm interpolation.
f : [0, 1] -> [0, 1]
f(0)=0
f(1)=1
f is strictly increase

Parameters:

t - Value to interpolate in [0, 1]

Returns:

Interpolated result in [0, 1]

interpolationSinus

public static double interpolationSinus(double t)

Compute sinus interpolation.
f : [0, 1] -> [0, 1]
f(0)=0
f(1)=1
f is strictly increase

Parameters:

t - Value to interpolate in [0, 1]

Returns:

Interpolated result in [0, 1]

isNul

public static boolean isNul(double real)

Indicates if a double is zero

Parameters:

real - Double to test

Returns:

true if zero

limit0_255

public static int limit0_255(int integer)

Return the given integer, if the integer is in [0, 255]. If integer<0, we return 0, if integer>255, we return 255

Parameters:

integer - Integer to limit in [0, 255]

Returns:

Limited integer

lowerCommonMultiple

public static int lowerCommonMultiple(int integer1,
                      int integer2)

Compute the Lower Common Multiple of two integers.
If both integers are 0, 0 is return

Parameters:

integer1 - First integer

integer2 - Second integer

Returns:

LCM

max

public static final double max(double... doubles)

Maximum of several double

Parameters:

doubles - Doubles to have the maximum

Returns:

Maximum of doubles

maxIntegers

public static final int maxIntegers(int... integers)

Maximum of several integers

Parameters:

integers - Integer to have the maximum

Returns:

Maximum of integers

min

public static final double min(double... doubles)

Minimum of several double

Parameters:

doubles - Doubles to have the minimum

Returns:

Minimum of doubles

minIntegers

public static final int minIntegers(int... integers)

Minimum of several integers

Parameters:

integers - Integer to have the minimum

Returns:

Minimum of integers

modulo

public static double modulo(double real,
            double modulo)

Compute the modulo of a real

Parameters:

real - Real to modulate

modulo - Modulo to use

Returns:

Result

modulo

public static int modulo(int integer,
         int modulo)

Mathematical modulo.
For computer -1 modulo 2 is -1, but in Mathematic -1[2]=1 (-1[2] : -1 modulo 2)

Parameters:

integer - Integer to modulate

modulo - Modulo to apply

Returns:

Mathematical modulo : integer[modulo]

modulo

public static long modulo(long integer,
          long modulo)

Mathematical modulo.
For computer -1 modulo 2 is -1, but in Mathematic -1[2]=1 (-1[2] : -1 modulo 2)

Parameters:

integer - Integer to modulate

modulo - Modulo to apply

Returns:

Mathematical modulo : integer[modulo]

moduloInterval

public static double moduloInterval(double real,
                    double min,
                    double max)

Modulate a real inside an interval

Parameters:

real - Real to modulate

min - Minimum of interval

max - Maximum of interval

Returns:

Modulated value

PCubique

public static double PCubique(double cp,
              double p1,
              double p2,
              double p3,
              double t)

Compute the cubic interpolation

Parameters:

cp - Start value

p1 - First control point

p2 - Second control point

p3 - Third control point

t - Factor in [0, 1]

Returns:

Interpolation

PCubiques

public static double[] PCubiques(double cp,
                 double p1,
                 double p2,
                 double p3,
                 int precision,
                 double[] cub)

Compute several cubic interpolation

Parameters:

cp - Start value

p1 - First control point

p2 - Second control point

p3 - Third control point

precision - Number of interpolation

cub - Where write interpolations

Returns:

Interpolations

pow

public static long pow(long integer,
       long pow)

Power of integer, more fast than Math.pow(double, double) for some case.
integer^pow

Parameters:

integer - Integer to power of

pow - Power to put

Returns:

The result

PQuadrique

public static double PQuadrique(double cp,
                double p1,
                double p2,
                double t)

Compute the quadric interpolation

Parameters:

cp - Start value

p1 - First control point

p2 - Second control point

t - Factor in [0, 1]

Returns:

Interpolation

PQuadriques

public static double[] PQuadriques(double cp,
                   double p1,
                   double p2,
                   int precision,
                   double[] quad)

Compute several quadric interpolation

Parameters:

cp - Start value

p1 - First control point

p2 - Second control point

precision - Number of interpolation

quad - Where write interpolations

Returns:

Interpolations

sign

public static int sign(double real)

Sign of a double.
The answer is like follow table:

Double is	Then return
< 0	-1
= 0	0
> 0	1

Parameters:

real - Double to have its sign

Returns:

Double sign (-1, 0 or 1)

sign

public static final int sign(int integer)

Sign of an integer.
It returns

-1	If integer is <0
0	If integer is 0
1	If integer is >0

Parameters:

integer - Integer to have sign

Returns:

Integer sign

sign

public static int sign(long integer)

Sign of an integer.
The answer is like follow table:

Integer is	Then return
< 0	-1
= 0	0
> 0	1

Parameters:

integer - Integer to have its sign

Returns:

Integer sign (-1, 0 or 1)