RationalNumber

java.lang.Object
- org.spaceroots.mantissa.algebra.RationalNumber

All Implemented Interfaces:

java.io.Serializable
```
public class RationalNumber
extends java.lang.Object
implements java.io.Serializable
```
This class implements reduced rational numbers.
Instances of this class are immutable.

Version:

$Id: RationalNumber.java 1711 2006-12-13 21:27:51Z luc $

Author:

L. Maisonobe

See Also:

Serialized Form

Field Summary

Fields
Modifier and Type Field and Description

static RationalNumber ONE
One as a rational numer.

static RationalNumber ZERO
Zero as a rational numer.

Fields
Modifier and Type	Field and Description
`static RationalNumber`	`ONE` One as a rational numer.
`static RationalNumber`	`ZERO` Zero as a rational numer.

Constructor Summary

Constructors
Constructor and Description
`RationalNumber()` Simple constructor.
`RationalNumber(java.math.BigInteger i)` Simple constructor.
`RationalNumber(java.math.BigInteger numerator, java.math.BigInteger denominator)` Simple constructor.
`RationalNumber(long l)` Simple constructor.
`RationalNumber(long numerator, long denominator)` Simple constructor.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`static RationalNumber`	`abs(RationalNumber r)` Get the absolute value of a rational number.
`RationalNumber`	`add(java.math.BigInteger l)` Add an integer to the instance.
`RationalNumber`	`add(long l)` Add an integer to the instance.
`RationalNumber`	`add(RationalNumber r)` Add a rational number to the instance.
`RationalNumber`	`divide(java.math.BigInteger l)` Divide the instance by an integer.
`RationalNumber`	`divide(long l)` Divide the instance by an integer.
`RationalNumber`	`divide(RationalNumber r)` Divide the instance by a rational number.
`double`	`doubleValue()` Return the `double` value of the instance.
`boolean`	`equals(java.lang.Object o)` Check if the instance is equal to another rational number.
`java.math.BigInteger`	`getDenominator()` Get the denominator.
`java.math.BigInteger`	`getNumerator()` Get the numerator.
`int`	`hashCode()` Returns a hash code value for the object.
`RationalNumber`	`invert()` Invert the instance.
`boolean`	`isInteger()` Check if the number is integer.
`boolean`	`isNegative()` Check if the number is negative.
`boolean`	`isOne()` Check if the number is one.
`boolean`	`isZero()` Check if the number is zero.
`RationalNumber`	`multiply(java.math.BigInteger l)` Multiply the instance by an integer.
`RationalNumber`	`multiply(long l)` Multiply the instance by an integer.
`RationalNumber`	`multiply(RationalNumber r)` Multiply the instance by a rational number.
`RationalNumber`	`negate()` Negate the instance.
`RationalNumber`	`subtract(java.math.BigInteger l)` Subtract an integer from the instance.
`RationalNumber`	`subtract(long l)` Subtract an integer from the instance.
`RationalNumber`	`subtract(RationalNumber r)` Subtract a rational number from the instance.
`java.lang.String`	`toString()` Returns a string representation of the rational number.

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait

- Field Detail
  - ZERO
```
public static final RationalNumber ZERO
```
    Zero as a rational numer.
  - ONE
```
public static final RationalNumber ONE
```
    One as a rational numer.
- Constructor Detail
  - RationalNumber
```
public RationalNumber()
```
    Simple constructor. Build a null rational number
  - RationalNumber
```
public RationalNumber(long numerator,
                      long denominator)
```
    Simple constructor. Build a rational number from a numerator and a denominator.
    
    Parameters:
    
    numerator - numerator of the rational number
    
    denominator - denominator of the rational number
    
    Throws:
    
    java.lang.ArithmeticException - if the denominator is zero
  - RationalNumber
```
public RationalNumber(java.math.BigInteger numerator,
                      java.math.BigInteger denominator)
```
    Simple constructor. Build a rational number from a numerator and a denominator.
    
    Parameters:
    
    numerator - numerator of the rational number
    
    denominator - denominator of the rational number
    
    Throws:
    
    java.lang.ArithmeticException - if the denominator is zero
  - RationalNumber
```
public RationalNumber(long l)
```
    Simple constructor. Build a rational number from a single integer
    
    Parameters:
    
    l - value of the rational number
  - RationalNumber
```
public RationalNumber(java.math.BigInteger i)
```
    Simple constructor. Build a rational number from a single integer
    
    Parameters:
    
    i - value of the rational number
- Method Detail
  - negate
```
public RationalNumber negate()
```
    Negate the instance.
    
    Returns:
    
    a new rational number, opposite to the isntance
  - add
```
public RationalNumber add(long l)
```
    Add an integer to the instance.
    
    Parameters:
    
    l - integer to add
    
    Returns:
    
    a new rational number which is the sum of the instance and l
  - add
```
public RationalNumber add(java.math.BigInteger l)
```
    Add an integer to the instance.
    
    Parameters:
    
    l - integer to add
    
    Returns:
    
    a new rational number which is the sum of the instance and l
  - add
```
public RationalNumber add(RationalNumber r)
```
    Add a rational number to the instance.
    
    Parameters:
    
    r - rational number to add
    
    Returns:
    
    a new rational number which is the sum of the instance and r
  - subtract
```
public RationalNumber subtract(long l)
```
    Subtract an integer from the instance.
    
    Parameters:
    
    l - integer to subtract
    
    Returns:
    
    a new rational number which is the difference the instance minus l
  - subtract
```
public RationalNumber subtract(java.math.BigInteger l)
```
    Subtract an integer from the instance.
    
    Parameters:
    
    l - integer to subtract
    
    Returns:
    
    a new rational number which is the difference the instance minus l
  - subtract
```
public RationalNumber subtract(RationalNumber r)
```
    Subtract a rational number from the instance.
    
    Parameters:
    
    r - rational number to subtract
    
    Returns:
    
    a new rational number which is the difference the instance minus r
  - multiply
```
public RationalNumber multiply(long l)
```
    Multiply the instance by an integer.
    
    Parameters:
    
    l - integer to multiply by
    
    Returns:
    
    a new rational number which is the produc of the instance by l
  - multiply
```
public RationalNumber multiply(java.math.BigInteger l)
```
    Multiply the instance by an integer.
    
    Parameters:
    
    l - integer to multiply by
    
    Returns:
    
    a new rational number which is the produc of the instance by l
  - multiply
```
public RationalNumber multiply(RationalNumber r)
```
    Multiply the instance by a rational number.
    
    Parameters:
    
    r - rational number to multiply the instance with
    
    Returns:
    
    a new rational number which is the product of the instance and r
  - divide
```
public RationalNumber divide(long l)
```
    Divide the instance by an integer.
    
    Parameters:
    
    l - integer to divide by
    
    Returns:
    
    a new rational number which is the quotient of the instance by l
    
    Throws:
    
    java.lang.ArithmeticException - if l is zero
  - divide
```
public RationalNumber divide(java.math.BigInteger l)
```
    Divide the instance by an integer.
    
    Parameters:
    
    l - integer to divide by
    
    Returns:
    
    a new rational number which is the quotient of the instance by l
    
    Throws:
    
    java.lang.ArithmeticException - if l is zero
  - divide
```
public RationalNumber divide(RationalNumber r)
```
    Divide the instance by a rational number.
    
    Parameters:
    
    r - rational number to divide by
    
    Returns:
    
    a new rational number which is the quotient of the instance by r
    
    Throws:
    
    java.lang.ArithmeticException - if r is zero
  - invert
```
public RationalNumber invert()
```
    Invert the instance.
    
    Returns:
    
    the inverse of the instance
    
    Throws:
    
    java.lang.ArithmeticException - if the instance is zero
  - getNumerator
```
public java.math.BigInteger getNumerator()
```
    Get the numerator.
    
    Returns:
    
    the signed numerator
  - getDenominator
```
public java.math.BigInteger getDenominator()
```
    Get the denominator.
    
    Returns:
    
    the denominator (always positive)
  - isZero
```
public boolean isZero()
```
    Check if the number is zero.
    
    Returns:
    
    true if the number is zero
  - isOne
```
public boolean isOne()
```
    Check if the number is one.
    
    Returns:
    
    true if the number is one
  - isInteger
```
public boolean isInteger()
```
    Check if the number is integer.
    
    Returns:
    
    true if the number is an integer
  - isNegative
```
public boolean isNegative()
```
    Check if the number is negative.
    
    Returns:
    
    true if the number is negative
  - abs
```
public static RationalNumber abs(RationalNumber r)
```
    Get the absolute value of a rational number.
    
    Parameters:
    
    r - rational number from which we want the absolute value
    
    Returns:
    
    a new rational number which is the absolute value of r
  - doubleValue
```
public double doubleValue()
```
    Return the double value of the instance.
    
    Returns:
    
    the double value of the instance
  - equals
```
public boolean equals(java.lang.Object o)
```
    Check if the instance is equal to another rational number. Equality here is having the same value.
    
    Overrides:
    
    equals in class java.lang.Object
    
    Returns:
    
    true if the object is a rational number which has the same value as the instance
  - hashCode
```
public int hashCode()
```
    Returns a hash code value for the object. The hash code value is computed from the reduced numerator and denominator, hence equal rational numbers have the same hash code, as required by the method specification.
    
    Overrides:
    
    hashCode in class java.lang.Object
    
    Returns:
    
    a hash code value for this object.
  - toString
```
public java.lang.String toString()
```
    Returns a string representation of the rational number. The representation is reduced: there is no common factor left between the numerator and the denominator. The '/' character and the denominator are displayed only if the denominator is not one. The sign is on the numerator.
    
    Overrides:
    
    toString in class java.lang.Object
    
    Returns:
    
    string representation of the rational number

Class RationalNumber

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

ZERO

ONE

Constructor Detail

RationalNumber

RationalNumber

RationalNumber

RationalNumber

RationalNumber

Method Detail

negate

add

add

add

subtract

subtract

subtract

multiply

multiply

multiply

divide

divide

divide

invert

getNumerator

getDenominator

isZero

isOne

isInteger

isNegative

abs

doubleValue

equals

hashCode

toString