public abstract class MathUtil

Object
MathUtil

MathUtil for Java ME. This fills the gap in Java ME Math with a port of Sun’s public FDLIBM C-library for IEEE-754.

Constructors

public MathUtil()

Methods

`public static final double exp(double a)`	Return Math.E to the exponent a. This in turn uses ieee7854_exp(double).
`public static final double log(double a)`	Return the natural logarithm, ln(a), as it relates to Math.E.
`public static final double log10(double a)`	Return the common base-10 logarithm, log10(a).
`public static final double pow(double a, double b)`	Return a to the power of b, sometimes written as a ** b but not to be confused with the bitwise ^ operator. This in turn uses ieee7854_log(double).
`public static final double asin(double a)`	Return the arcsine of a.
`public static final double acos(double a)`	Return the arccosine of a.
`public static final double atan(double a)`	Return the arctangent of a, call it b, where a = tan(b).
`public static final double atan2(double b, double a)`	For any real arguments x and y not both equal to zero, atan2(y, x) is the angle in radians between the positive x-axis of a plane and the point given by the coordinates (x, y) on it.
`public static double scalb(double x, int n)`	scalbn (double x, int n) scalbn(x,n) returns x* 2**n computed by exponent manipulation rather than by actually performing an exponentiation or a multiplication.
`public static double scalbn(double x, int n)`	Deprecated Please update your code to use scalb
`public static double copySign(double x, double y)`
`public static double copysign(double x, double y)`	Deprecated Please update your code to use copySign
`public static double ulp(double d)`	Returns the size of an ulp (units in the last place) of the argument.
`public static double nextAfter(double start, double direction)`	Returns the next representable floating point number after the first argument in the direction of the second argument.
`public static int round(float a)`	Rounds the number to the closest integer
`public static long round(double a)`	Rounds the number to the closest integer
`public static int floor(float a)`	Rounds the number down
`public static long floor(double a)`	Rounds the number down
`public static int compare(float f1, float f2)`	Compares the two specified `float` values.
`public static int compare(double d1, double d2)`	Compares the two specified `double` values.

Inherited methods

From Object

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

Constructor details

MathUtil

public MathUtil()

Method details

exp

public static final double exp(double a)

Return Math.E to the exponent a. This in turn uses ieee7854_exp(double).

log

public static final double log(double a)

Return the natural logarithm, ln(a), as it relates to Math.E. This in turn uses ieee7854_log(double).

log10

public static final double log10(double a)

Return the common base-10 logarithm, log10(a). This in turn uses ieee7854_log(double)/ieee7854_log(10.0).

pow

public static final double pow(double a, double b)

Return a to the power of b, sometimes written as a ** b but not to be confused with the bitwise ^ operator. This in turn uses ieee7854_log(double).

asin

public static final double asin(double a)

Return the arcsine of a.

acos

public static final double acos(double a)

Return the arccosine of a.

atan

public static final double atan(double a)

Return the arctangent of a, call it b, where a = tan(b).

atan2

public static final double atan2(double b, double a)

For any real arguments x and y not both equal to zero, atan2(y, x) is the angle in radians between the positive x-axis of a plane and the point given by the coordinates (x, y) on it. The angle is positive for counter-clockwise angles (upper half-plane, y > 0), and negative for clockwise angles (lower half-plane, y < 0). This in turn uses ieee7854_arctan2(double).

scalb

public static double scalb(double x, int n)

scalbn (double x, int n) scalbn(x,n) returns x* 2**n computed by exponent manipulation rather than by actually performing an exponentiation or a multiplication.

scalbn

public static double scalbn(double x, int n)

Deprecated. Please update your code to use scalb

Please update your code to use scalb

Returns

scalb(x, n)

copySign

public static double copySign(double x, double y)

copysign

public static double copysign(double x, double y)

Deprecated. Please update your code to use copySign

a double: the number

Returns

a rounded down number

compare

public static int compare(float f1, float f2)

Compares the two specified float values. The sign of the integer value returned is the same as that of the integer that would be returned by the call:

float f1 = 1.5f;
float f2 = 2.5f;
int result = new Float(f1).compareTo(new Float(f2));
Form hi = new Form("MathUtil.compare(float)", BoxLayout.y());
hi.add(new Label("Float.compareTo result: " + result));
hi.show();

Parameters

f1 float: the first float to compare.
f2 float: the second float to compare.

Returns

the value 0 if f1 is numerically equal to f2; a value less than 0 if f1 is numerically less than f2; and a value greater than 0 if f1 is numerically greater than f2.

compare

public static int compare(double d1, double d2)

Compares the two specified double values. The sign of the integer value returned is the same as that of the integer that would be returned by the call:

double d1 = 1.5;
double d2 = 2.5;
int result = new Double(d1).compareTo(new Double(d2));
Form hi = new Form("MathUtil.compare(double)", BoxLayout.y());
hi.add(new Label("Double.compareTo result: " + result));
hi.show();

Parameters

d1 double: the first double to compare
d2 double: the second double to compare

Returns

the value 0 if d1 is numerically equal to d2; a value less than 0 if d1 is numerically less than d2; and a value greater than 0 if d1 is numerically greater than d2.