JSci.maths
Class ExtraMath

java.lang.Object
  extended byJSci.maths.AbstractMath
      extended byJSci.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 infinity.
static double asinh(double x)
          Returns the arc hyperbolic sine of a double, in the range of -infinity through infinity.
static double atanh(double x)
          Returns the arc hyperbolic tangent of a double, in the range of -infinity through infinity.
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 ab.

Parameters:
a - an integer.
b - a positive integer.

pow2

public static int pow2(int a)
Returns 2a.

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 -infinity through infinity.

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 infinity.

Parameters:
x - a double.

atanh

public static double atanh(double x)
Returns the arc hyperbolic tangent of a double, in the range of -infinity through infinity.

Parameters:
x - a double.