NumberSystem (Units of Measurement Reference Implementation 2.2 API)

All Known Implementing Classes:

DefaultNumberSystem
```
public interface NumberSystem
```
Provides arithmetic Number operations on an implementation specific set of Number types.
Let S be the set of possible Number values within the (given) set of Number types.
Then S is closed under the collection of NumberSystem's methods.

Implementation Note:
Given S the set of possible Number values within implementation specific set of (supported) Number types:
- implemented methods must support any Number arguments from S
- implemented methods must also have their Number results to be in S

Since:

2.1, November 21, 2020

Author:

Andi Huber, Werner Keil

See Also:

Closure (wikipedia)

Nested Class Summary

Nested Classes
Modifier and Type Interface Description

static class NumberSystem.DivisionResult
Immutable value type, holder of 2 numbers.

Nested Classes
Modifier and Type	Interface	Description
`static class`	`NumberSystem.DivisionResult`	Immutable value type, holder of 2 numbers.

Method Summary

All Methods Instance Methods Abstract Methods Default Methods
Modifier and Type	Method	Description
`Number`	`abs(Number number)`	Returns the absolute of given `number` as a `Number` that best represents the arithmetic result within the set of number types this NumberSystem supports.
`Number`	`add(Number x, Number y)`	Returns the sum of given `x` and `y` as a `Number` that best represents the arithmetic result within the set of number types this NumberSystem supports.
`int`	`compare(Number x, Number y)`	Compares two `Number` values numerically.
`Number`	`divide(Number x, Number y)`	Returns the division of given `x` and `y` as a `Number` that best represents the arithmetic result within the set of number types this NumberSystem supports.
`Number[]`	`divideAndRemainder(Number x, Number y, boolean roundRemainderTowardsZero)`	Returns a two-element Number array containing {x / y, x % y}
`default boolean`	`equals(Number x, Number y)`
`Number`	`exp(Number number)`	Returns Euler's Constant to the power of of given `number` as a `Number` that best represents the arithmetic result within the set of number types this NumberSystem supports.
`boolean`	`isInteger(Number number)`	Checks whether given `number` has fractional parts or not.
`boolean`	`isLessThanOne(Number number)`
`boolean`	`isOne(Number number)`
`boolean`	`isZero(Number number)`
`Number`	`log(Number number)`	Returns the natural logarithm of given `number` as a `Number` that best represents the arithmetic result within the set of number types this NumberSystem supports.
`Number`	`multiply(Number x, Number y)`	Returns the product of given `x` and `y` as a `Number` that best represents the arithmetic result within the set of number types this NumberSystem supports.
`Number`	`narrow(Number number)`	'Narrows' given `number` as a `Number` that best represents the numeric value within the set of number types this NumberSystem supports.
`Number`	`negate(Number number)`	Returns the negation of given `number` as a `Number` that best represents the arithmetic result within the set of number types this NumberSystem supports.
`Number`	`power(Number number, int exponent)`	Returns given `number` to the power of `exponent` as a `Number` that best represents the arithmetic result within the set of number types this NumberSystem supports.
`Number`	`reciprocal(Number number)`	Returns the reciprocal of given `number` as a `Number` that best represents the arithmetic result within the set of number types this NumberSystem supports.
`int`	`signum(Number number)`	Returns the signum function of given `number`.
`Number`	`subtract(Number x, Number y)`	Returns the difference of given `x` and `y` as a `Number` that best represents the arithmetic result within the set of number types this NumberSystem supports.

- Method Detail
  - add
```
Number add(Number x,
           Number y)
```
    Returns the sum of given x and y as a Number that best represents the arithmetic result within the set of number types this NumberSystem supports.
    
    Parameters:
    
    x -
    
    y -
    
    Returns:
    
    x + y
  - subtract
```
Number subtract(Number x,
                Number y)
```
    Returns the difference of given x and y as a Number that best represents the arithmetic result within the set of number types this NumberSystem supports.
    
    Parameters:
    
    x -
    
    y -
    
    Returns:
    
    x - y
  - multiply
```
Number multiply(Number x,
                Number y)
```
    Returns the product of given x and y as a Number that best represents the arithmetic result within the set of number types this NumberSystem supports.
    
    Parameters:
    
    x -
    
    y -
    
    Returns:
    
    x * y
  - divide
```
Number divide(Number x,
              Number y)
```
    Returns the division of given x and y as a Number that best represents the arithmetic result within the set of number types this NumberSystem supports.
    
    Parameters:
    
    x -
    
    y -
    
    Returns:
    
    x / y
  - divideAndRemainder
```
Number[] divideAndRemainder(Number x,
                            Number y,
                            boolean roundRemainderTowardsZero)
```
    Returns a two-element Number array containing {x / y, x % y}
    
    Parameters:
    
    x -
    
    y -
    
    roundRemainderTowardsZero - - whether the division remainder should be rounded towards zero
    
    Returns:
  - power
```
Number power(Number number,
             int exponent)
```
    Returns given number to the power of exponent as a Number that best represents the arithmetic result within the set of number types this NumberSystem supports.
    
    Parameters:
    
    number -
    
    exponent - - an integer
    
    Returns:
    
    number^exponent
    
    Throws:
    
    ArithmeticException - if number and exponent are ZERO
  - reciprocal
```
Number reciprocal(Number number)
```
    Returns the reciprocal of given number as a Number that best represents the arithmetic result within the set of number types this NumberSystem supports.
    
    Parameters:
    
    number -
    
    Returns:
    
    number^-1
  - negate
```
Number negate(Number number)
```
    Returns the negation of given number as a Number that best represents the arithmetic result within the set of number types this NumberSystem supports.
    
    Parameters:
    
    number -
    
    Returns:
    
    -number
  - signum
```
int signum(Number number)
```
    Returns the signum function of given number.
    
    Parameters:
    
    number -
    
    Returns:
    
    signum(number)
  - abs
```
Number abs(Number number)
```
    Returns the absolute of given number as a Number that best represents the arithmetic result within the set of number types this NumberSystem supports.
    
    Parameters:
    
    number -
    
    Returns:
    
    abs(number)
  - exp
```
Number exp(Number number)
```
    Returns Euler's Constant to the power of of given number as a Number that best represents the arithmetic result within the set of number types this NumberSystem supports.
    
    Parameters:
    
    number -
    
    Returns:
    
    e^number, with e Euler's Constant)
  - log
```
Number log(Number number)
```
    Returns the natural logarithm of given number as a Number that best represents the arithmetic result within the set of number types this NumberSystem supports.
    
    Parameters:
    
    number -
    
    Returns:
    
    natural logarithm of number
  - narrow
```
Number narrow(Number number)
```
    'Narrows' given number as a Number that best represents the numeric value within the set of number types this NumberSystem supports.
    eg. A BigInteger that is within range of Java's Long type can be narrowed to Long w/o loss of precision.
    
    Parameters:
    
    number -
    
    Returns:
    
    'best' representation of number w/o loss of precision
  - compare
```
int compare(Number x,
            Number y)
```
    Compares two Number values numerically.
    
    Parameters:
    
    x -
    
    y -
    
    Returns:
    
    the value 0 if x == y; a value less than 0 if x < y; and a value greater than 0 if x > y
  - isZero
```
boolean isZero(Number number)
```
  - isOne
```
boolean isOne(Number number)
```
  - isLessThanOne
```
boolean isLessThanOne(Number number)
```
  - isInteger
```
boolean isInteger(Number number)
```
    Checks whether given number has fractional parts or not.
    
    Parameters:
    
    number -
    
    Returns:
    
    whether number represents a whole number
  - equals
```
default boolean equals(Number x,
                       Number y)
```
    Parameters:
    
    x -
    
    y -
    
    Returns:

Interface NumberSystem

Nested Class Summary

Method Summary

Method Detail

add

subtract

multiply

divide

divideAndRemainder

power

reciprocal

negate

signum

abs

exp

log

narrow

compare

isZero

isOne

isLessThanOne

isInteger

equals