JSci.maths
Class ExtraMath

java.lang.Object
  JSci.maths.AbstractMath
      JSci.maths.ExtraMath

public final class ExtraMath

extends AbstractMath

The extra math library. Provides extra functions not in java.lang.Math class. This class cannot be subclassed or instantiated because all methods are static.

Method Summary

static double	acosh(double x) Returns the arc hyperbolic cosine of a double, in the range of 0.0 through .
static double	asinh(double x) Returns the arc hyperbolic sine of a double, in the range of - through .
static double	atanh(double x) Returns the arc hyperbolic tangent of a double, in the range of - through .
static double	binomial(double n, double k) Returns the binomial coefficient (n k).
static int	binomial(int n, int k) Returns the binomial coefficient (n k).
static double	cosh(double x) Returns the hyperbolic cosine of a double.
static double	factorial(double x) Returns the factorial.
static double	hypot(double x, double y) Returns sqrt(x2+y2).
static double	log10(double x) Returns the base 10 logarithm of a double.
static double	logFactorial(double x) Returns the natural logarithm of the factorial.
static int	pow(int a, int b) Returns ab.
static int	pow2(int a) Returns 2a.
static double	random(double min, double max) Returns a random number within a specified range.
static double	round(double x, int significant) Rounds a number to so many significant figures.
static int	sign(double x) Returns the sign of a number.
static double	sinh(double x) Returns the hyperbolic sine of a double.
static double	tanh(double x) Returns the hyperbolic tangent of a double.

Methods inherited from class java.lang.Object

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

Method Detail

round

public static double round(double x,
                           int significant)

Rounds a number to so many significant figures.

Parameters:

x - a number to be rounded.

significant - number of significant figures to round to.

random

public static double random(double min,
                            double max)

Returns a random number within a specified range.

sign

public static int sign(double x)

Returns the sign of a number.

Returns:

1 if x>0.0, -1 if x<0.0, else 0.

hypot

public static double hypot(double x,
                           double y)

Returns sqrt(x²+y²).

pow

public static int pow(int a,
                      int b)

Returns a^b.

Parameters:

a - an integer.

b - a positive integer.

pow2

public static int pow2(int a)

Returns 2^a.

Parameters:

a - a positive integer.

factorial

public static double factorial(double x)

Returns the factorial. (Wrapper for the gamma function).

Parameters:

x - a double.

See Also:

SpecialMath.gamma(double)

logFactorial

public static double logFactorial(double x)

Returns the natural logarithm of the factorial. (Wrapper for the log gamma function).

Parameters:

x - a double.

See Also:

SpecialMath.logGamma(double)

binomial

public static int binomial(int n,
                           int k)

Returns the binomial coefficient (n k). Uses Pascal's recursion formula.

Parameters:

n - an integer.

k - an integer.

PlanetMath references:

PascalsRule

binomial

public static double binomial(double n,
                              double k)

Returns the binomial coefficient (n k). Uses gamma functions.

Parameters:

n - a double.

k - a double.

PlanetMath references:

BinomialCoefficient

log10

public static double log10(double x)

Returns the base 10 logarithm of a double.

Parameters:

x - a double.

sinh

public static double sinh(double x)

Returns the hyperbolic sine of a double.

Parameters:

x - a double.

cosh

public static double cosh(double x)

Returns the hyperbolic cosine of a double.

Parameters:

x - a double.

tanh

public static double tanh(double x)

Returns the hyperbolic tangent of a double.

Parameters:

x - a double.

asinh

public static double asinh(double x)

Returns the arc hyperbolic sine of a double, in the range of - through .

Parameters:

x - a double.

acosh

public static double acosh(double x)

Returns the arc hyperbolic cosine of a double, in the range of 0.0 through .

Parameters:

x - a double.

atanh

public static double atanh(double x)

Returns the arc hyperbolic tangent of a double, in the range of - through .

Parameters:

x - a double.