edu.neu.ccs
Class F

java.lang.Object
  edu.neu.ccs.F

public class F

extends Object

Class F is a collection of static methods that make it easy to create and manipulate functions of one argument, that is, objects that implement the interface Function.OneArg. Such function objects must have a method of the form:

public double evaluate(double x)

This class defines methods that make all functions of one argument in the following packages into objects:

• java.lang.Math
• edu.neu.ccs.util.MathUtilities

In addition, the class defines methods to add, subtract, multiply, divide, and compose functions of one argument.

Finally, some additional useful methods are defined.

Class F cannot be instantiated.

In 2.5.0, made a slight change to the random function and removed the related functional method randomDouble.

Since:

2.5.0

Version:

2.5.0

Field Summary

static Function.OneArg	abs The function x --> abs(x).
static Function.OneArg	acos The function x --> acos(x).
static Function.OneArg	acosdeg The function x --> acosdeg(x).
static Function.OneArg	asin The function x --> asin(x).
static Function.OneArg	asindeg The function x --> asindeg(x).
static Function.OneArg	atan The function x --> atan(x).
static Function.OneArg	atandeg The function x --> atandeg(x).
static Function.OneArg	ceil The function x --> ceil(x).
static Function.OneArg	cos The function x --> cos(x).
static Function.OneArg	cosdeg The function x --> cosdeg(x).
static Function.OneArg	exp The function x --> exp(x).
static Function.OneArg	exp10 The function x --> 10-to-the-power-x = exp(x * log(10)).
static Function.OneArg	exp2 The function x --> 2-to-the-power-x = exp(x * log(2)).
static Function.OneArg	floor The function x --> floor(x).
static Function.OneArg	identity The identity function x --> x.
static Function.OneArg	log The function x --> log(x).
static Function.OneArg	log10 The function x --> log-base-10(x) = log(x) / log(10).
static Function.OneArg	log2 The function x --> log-base-2(x) = log(x) / log(2).
private static double	logOf10 The constant log(10).
private static double	logOf2 The constant log(2).
static Function.OneArg	random The function x --> Math.random() * x.
static Function.OneArg	rint The function x --> rint(x).
static Function.OneArg	sin The function x --> sin(x).
static Function.OneArg	sindeg The function x --> sindeg(x).
static Function.OneArg	sqrt The function x --> sqrt(x).
static Function.OneArg	tan The function x --> tan(x).
static Function.OneArg	tandeg The function x --> tandeg(x).
static Function.OneArg	toDegrees The function x --> toDegrees(x).
static Function.OneArg	toRadians The function x --> toRadians(x).

Constructor Summary

private

F()

Method Summary

static Function.OneArg	add(Function.OneArg f, Function.OneArg g) The function to add functions f,g: f + g.
static Function.OneArg	atan2(Function.OneArg f, Function.OneArg g) The function to compute the function atan2(f, g).
static Function.OneArg	atan2deg(Function.OneArg f, Function.OneArg g) The function to compute the function atan2deg(f, g).
static Function.OneArg	aToPowerX(double a) The function x --> a-to-the-power-x = Math.pow(a, x).
private static void	checkNull(String method, Function.OneArg f) Check for null function arguments and throw a NullPointerException if necessary.
private static void	checkNull(String method, Function.OneArg f, Function.OneArg g) Check for null function arguments and throw a NullPointerException if necessary.
static Function.OneArg	compose(Function.OneArg f, Function.OneArg g) The function to compose functions f,g: x --> f(g(x)).
static Function.OneArg	constant(double c) The constant function x --> c.
static Function.OneArg	divide(Function.OneArg f, Function.OneArg g) The function to divide functions f,g: f / g.
static Function.OneArg	linear(double a, double b) The linear function x --> a * x + b.
static Function.OneArg	max(Function.OneArg f, Function.OneArg g) The function to compute the function max(f, g).
static Function.OneArg	min(Function.OneArg f, Function.OneArg g) The function to compute the function min(f, g).
static Function.OneArg	multiply(Function.OneArg f, Function.OneArg g) The function to multiply functions f,g: f * g.
static Function.OneArg	pow(double a, Function.OneArg f) The function to compute the function a-to-the-power-f = Math.pow(a,f.evaluate(x)).
static Function.OneArg	pow(Function.OneArg f, double a) The function to compute the function f-to-the-power-a = Math.pow(f.evaluate(x),a).
static Function.OneArg	pow(Function.OneArg f, Function.OneArg g) The function to compute the function f-to-the-power-g = Math.pow(f.evaluate(x),g.evaluate(x)).
static Function.OneArg	power(Function.OneArg f, int n) The function to compute the function f-to-the-power-n = MathUtilities.power(f.evaluate(x),n).
static Function.OneArg	scale(double a) The scale function x --> a * x.
static Function.OneArg	subtract(Function.OneArg f, Function.OneArg g) The function to subtract functions f,g: f - g.
static Function.OneArg	translate(double b) The translate function x --> x + b.
static Function.OneArg	xToPowerA(double a) The function x --> x-to-the-power-a = Math.pow(x, a).
static Function.OneArg	xToPowerN(int n) The function x --> x-to-the-power-n = MathUtilities.power(x,n).

Methods inherited from class java.lang.Object

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

Field Detail

logOf2

private static final double logOf2

The constant log(2).

logOf10

private static final double logOf10

The constant log(10).

identity

public static final Function.OneArg identity

The identity function x --> x.

abs

public static final Function.OneArg abs

The function x --> abs(x).

ceil

public static final Function.OneArg ceil

The function x --> ceil(x).

floor

public static final Function.OneArg floor

The function x --> floor(x).

rint

public static final Function.OneArg rint

The function x --> rint(x).

sin

public static final Function.OneArg sin

The function x --> sin(x).

cos

public static final Function.OneArg cos

The function x --> cos(x).

tan

public static final Function.OneArg tan

The function x --> tan(x).

asin

public static final Function.OneArg asin

The function x --> asin(x).

acos

public static final Function.OneArg acos

The function x --> acos(x).

atan

public static final Function.OneArg atan

The function x --> atan(x).

sindeg

public static final Function.OneArg sindeg

The function x --> sindeg(x).

cosdeg

public static final Function.OneArg cosdeg

The function x --> cosdeg(x).

tandeg

public static final Function.OneArg tandeg

The function x --> tandeg(x).

asindeg

public static final Function.OneArg asindeg

The function x --> asindeg(x).

acosdeg

public static final Function.OneArg acosdeg

The function x --> acosdeg(x).

atandeg

public static final Function.OneArg atandeg

The function x --> atandeg(x).

toDegrees

public static final Function.OneArg toDegrees

The function x --> toDegrees(x).

toRadians

public static final Function.OneArg toRadians

The function x --> toRadians(x).

exp

public static final Function.OneArg exp

The function x --> exp(x).

log

public static final Function.OneArg log

The function x --> log(x).

exp2

public static final Function.OneArg exp2

The function x --> 2-to-the-power-x = exp(x * log(2)).

log2

public static final Function.OneArg log2

The function x --> log-base-2(x) = log(x) / log(2).

exp10

public static final Function.OneArg exp10

The function x --> 10-to-the-power-x = exp(x * log(10)).

log10

public static final Function.OneArg log10

The function x --> log-base-10(x) = log(x) / log(10).

sqrt

public static final Function.OneArg sqrt

The function x --> sqrt(x).

random

public static final Function.OneArg random

The function x --> Math.random() * x.

In effect, returns a random number between 0 and x.

Constructor Detail

F

private F()

Method Detail

constant

public static Function.OneArg constant(double c)

The constant function x --> c.

Parameters:

c - the constant.

scale

public static Function.OneArg scale(double a)

The scale function x --> a * x.

Parameters:

a - the scale.

translate

public static Function.OneArg translate(double b)

The translate function x --> x + b.

Parameters:

b - the translate.

linear

public static Function.OneArg linear(double a,
                                     double b)

The linear function x --> a * x + b.

Parameters:

a - the scale.

b - the translate.

xToPowerN

public static Function.OneArg xToPowerN(int n)

The function x --> x-to-the-power-n = MathUtilities.power(x,n).

xToPowerA

public static Function.OneArg xToPowerA(double a)

The function x --> x-to-the-power-a = Math.pow(x, a).

aToPowerX

public static Function.OneArg aToPowerX(double a)

The function x --> a-to-the-power-x = Math.pow(a, x).

add

public static Function.OneArg add(Function.OneArg f,
                                  Function.OneArg g)

The function to add functions f,g: f + g.

subtract

public static Function.OneArg subtract(Function.OneArg f,
                                       Function.OneArg g)

The function to subtract functions f,g: f - g.

multiply

public static Function.OneArg multiply(Function.OneArg f,
                                       Function.OneArg g)

The function to multiply functions f,g: f * g.

divide

public static Function.OneArg divide(Function.OneArg f,
                                     Function.OneArg g)

The function to divide functions f,g: f / g.

compose

public static Function.OneArg compose(Function.OneArg f,
                                      Function.OneArg g)

The function to compose functions f,g: x --> f(g(x)).

min

public static Function.OneArg min(Function.OneArg f,
                                  Function.OneArg g)

The function to compute the function min(f, g).

max

public static Function.OneArg max(Function.OneArg f,
                                  Function.OneArg g)

The function to compute the function max(f, g).

power

public static Function.OneArg power(Function.OneArg f,
                                    int n)

The function to compute the function f-to-the-power-n = MathUtilities.power(f.evaluate(x),n).

pow

public static Function.OneArg pow(Function.OneArg f,
                                  double a)

The function to compute the function f-to-the-power-a = Math.pow(f.evaluate(x),a).

pow

public static Function.OneArg pow(double a,
                                  Function.OneArg f)

The function to compute the function a-to-the-power-f = Math.pow(a,f.evaluate(x)).

pow

public static Function.OneArg pow(Function.OneArg f,
                                  Function.OneArg g)

The function to compute the function f-to-the-power-g = Math.pow(f.evaluate(x),g.evaluate(x)).

atan2

public static Function.OneArg atan2(Function.OneArg f,
                                    Function.OneArg g)

The function to compute the function atan2(f, g).

atan2deg

public static Function.OneArg atan2deg(Function.OneArg f,
                                       Function.OneArg g)

The function to compute the function atan2deg(f, g).

checkNull

private static void checkNull(String method,
                              Function.OneArg f)

Check for null function arguments and throw a NullPointerException if necessary.

Parameters:

method - the string name of the method

f - the function argument

checkNull

private static void checkNull(String method,
                              Function.OneArg f,
                              Function.OneArg g)

Check for null function arguments and throw a NullPointerException if necessary.

Parameters:

method - the string name of the method

f - the first function argument

g - the second function argument