org.geotools.util

Class XMath

Object

XMath

public final class XMath
extends Object

Simple mathematical functions.

Since:

2.0

Author:

Martin Desruisseaux (IRD)

Method Summary

Modifier and Type	Method and Description
static double	next(double f) Finds the least double greater than f.
static float	next(float f) Finds the least float greater than f.
static double	previous(double f) Finds the greatest double less than f.
static float	previous(float f) Finds the greatest float less than f.
static double	rool(Class type, double value, int amount) Returns the next or previous representable number.

Methods inherited from class Object

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

Method Detail

next

public static float next(float f)

Finds the least float greater than f. If NaN, returns same value.

previous

public static float previous(float f)

Finds the greatest float less than f. If NaN, returns same value.

next

public static double next(double f)

Finds the least double greater than f. If NaN, returns same value.

See Also:

ChoiceFormat.nextDouble(double)

previous

public static double previous(double f)

Finds the greatest double less than f. If NaN, returns same value.

See Also:

ChoiceFormat.previousDouble(double)

rool

public static double rool(Class type,
                          double value,
                          int amount)
                   throws IllegalArgumentException

Returns the next or previous representable number. If amount is equals to 0, then this method returns the value unchanged. Otherwise, The operation performed depends on the specified type:

• If the type is Double, then this method is equivalent to invoking previous(double) if amount is equals to -1, or invoking next(double) if amount is equals to +1. If amount is smaller than -1 or greater than +1, then this method invokes previous(double) or next(double) in a loop for abs(amount) times.

• If the type is Float, then this method is equivalent to invoking previous(float) if amount is equals to -1, or invoking next(float) if amount is equals to +1. If amount is smaller than -1 or greater than +1, then this method invokes previous(float) or next(float) in a loop for abs(amount) times.

• If the type is an integer, then invoking this method is equivalent to computing value + amount.

Parameters:

type - The type. Should be the class of Double, Float, Long, Integer, Short or Byte.

value - The number to rool.

amount - -1 to return the previous representable number, +1 to return the next representable number, or 0 to return the number with no change.

Returns:

One of previous or next representable number as a double.

Throws:

IllegalArgumentException - if type is not one of supported types.