Catalano.Math

Class Special

java.lang.Object

Catalano.Math.Special

public final class Special
extends java.lang.Object

Set of special mathematic functions.

Method Summary

Modifier and Type	Method and Description
static double	Binomial(int n, int k) Computes the binomial coefficients C(n,k).
static double	BSpline(int n, double x) Computes the Basic Spline of order n.
static double	Epslon(double x) Estimates unit roundoff in quantities of size x.
static double	Erf(double x) Error function of the specified value.
static double	Erfc(double value) Complementary error function of the specified value.
static double	Expm1(double x) Compute exp(x) - 1 without loss of precision for small values of x.
static double	Factorial(int n) Computes the factorial of a number (n!).
static double	Log1m(double x) Computes log(1-x) without losing precision for small values of x.
static double	Log1p(double x) Computes log(1+x) without losing precision for small values of x.
static double	LogBinomial(int n, int k) Computes the log binomial Coefficients Log[C(n,k)].
static double	LogDiff(double lna, double lnc) Computes x + y without losing precision using ln(x) and ln(y).
static double	LogFactorial(int n) Returns the log factorial of a number (ln(n!))
static double	LogSum(double lna, double lnc) Computes x + y without losing precision using ln(x) and ln(y).
static double	LogSum(float lna, float lnc) Computes x + y without losing precision using ln(x) and ln(y).
static double	P1evl(double x, double[] coef, int n) Evaluates polynomial of degree N with assumption that coef[N] = 1.0
static double	Polevl(double x, double[] coef, int n) Evaluates polynomial of degree N.
static double	Sign(double a, double b) Returns A with the sign of B.

Methods inherited from class java.lang.Object

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

Method Detail

Erfc

public static double Erfc(double value)

Complementary error function of the specified value.

Parameters:

value - Value.

Returns:

Result.

Erf

public static double Erf(double x)

Error function of the specified value.

Parameters:

x - Value.

Returns:

Result.

Polevl

public static double Polevl(double x,
                            double[] coef,
                            int n)

Evaluates polynomial of degree N.

Parameters:

x - Value.

coef - Coefficient.

n - Degree.

Returns:

Result.

P1evl

public static double P1evl(double x,
                           double[] coef,
                           int n)

Evaluates polynomial of degree N with assumption that coef[N] = 1.0

Parameters:

x - Value.

coef - Coefficient.

n - Degree.

Returns:

Result.

BSpline

public static double BSpline(int n,
                             double x)

Computes the Basic Spline of order n.

Binomial

public static double Binomial(int n,
                              int k)

Computes the binomial coefficients C(n,k).

Parameters:

n - Coefficient.

k - Coefficient.

Returns:

Result.

LogBinomial

public static double LogBinomial(int n,
                                 int k)

Computes the log binomial Coefficients Log[C(n,k)].

Parameters:

n - Coefficient.

k - Coefficient.

Returns:

Result.

LogFactorial

public static double LogFactorial(int n)

Returns the log factorial of a number (ln(n!))

Parameters:

n - Number.

Returns:

Result.

Factorial

public static double Factorial(int n)

Computes the factorial of a number (n!).

Parameters:

n - Number.

Returns:

Result.

Log1m

public static double Log1m(double x)

Computes log(1-x) without losing precision for small values of x.

Parameters:

x - Value.

Returns:

Result.

Log1p

public static double Log1p(double x)

Computes log(1+x) without losing precision for small values of x.

Parameters:

x - Value.

Returns:

Result.

Expm1

public static double Expm1(double x)

Compute exp(x) - 1 without loss of precision for small values of x.

Parameters:

x - Value.

Returns:

Result.

Epslon

public static double Epslon(double x)

Estimates unit roundoff in quantities of size x.

Parameters:

x - Value.

Returns:

Result.

Sign

public static double Sign(double a,
                          double b)

Returns A with the sign of B.

Parameters:

a - Value.

b - Value.

Returns:

Result.

LogDiff

public static double LogDiff(double lna,
                             double lnc)

Computes x + y without losing precision using ln(x) and ln(y).

Parameters:

lna - Value.

lnc - Value.

Returns:

Result.

LogSum

public static double LogSum(double lna,
                            double lnc)

Computes x + y without losing precision using ln(x) and ln(y).

Parameters:

lna - Value.

lnc - Value.

Returns:

Result.

LogSum

public static double LogSum(float lna,
                            float lnc)

Computes x + y without losing precision using ln(x) and ln(y).

Parameters:

lna - Value.

lnc - Value.

Returns:

Result.