RatNum (hw API)

java.lang.Object
- java.lang.Number
- - hw2.RatNum

All Implemented Interfaces:

java.io.Serializable, java.lang.Comparable<RatNum>
```
public final class RatNum
extends java.lang.Number
implements java.lang.Comparable<RatNum>
```
RatNum represents an immutable rational number. It includes all of the elements in the set of rationals, as well as the special "NaN" (not-a-number) element that results from division by zero.
The "NaN" element is special in many ways. Any arithmetic operation (such as addition) involving "NaN" will return "NaN". With respect to comparison operations, such as less-than, "NaN" is considered equal to itself, and larger than all other rationals.
Examples of RatNums include "-1/13", "53/7", "4", "NaN", and "0".

See Also:

Serialized Form

Field Summary

Fields
Modifier and Type	Field and Description
`static RatNum`	`NaN` A constant holding a Not-a-Number (NaN) value of type RatNum
`static RatNum`	`ZERO` A constant holding a zero value of type RatNum

Constructor Summary

Constructors
Constructor and Description

RatNum(int n)

RatNum(int n, int d)

Constructors
Constructor and Description
`RatNum(int n)`
`RatNum(int n, int d)`

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`RatNum`	`add(RatNum arg)` Addition operation.
`int`	`compareTo(RatNum rn)` Compares two RatNums.
`RatNum`	`div(RatNum arg)` Division operation.
`double`	`doubleValue()` Approximates the value of this rational.
`boolean`	`equals(java.lang.Object obj)` Standard equality operation.
`float`	`floatValue()` Returns a float approximation for this.
`int`	`hashCode()` Standard hashCode function.
`int`	`intValue()` Returns an integer approximation for this.
`boolean`	`isNaN()` Returns true if this is NaN
`boolean`	`isNegative()` Returns true if this is negative.
`boolean`	`isPositive()` Returns true if this is positive.
`long`	`longValue()` Returns a long approximation for this.
`RatNum`	`mul(RatNum arg)` Multiplication operation.
`RatNum`	`negate()` Returns the additive inverse of this RatNum.
`RatNum`	`sub(RatNum arg)` Subtraction operation.
`java.lang.String`	`toString()`
`static RatNum`	`valueOf(java.lang.String ratStr)` Makes a RatNum from a string describing it.

Methods inherited from class java.lang.Number
byteValue, shortValue

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

- Field Detail
  - NaN
```
public static final RatNum NaN
```
    A constant holding a Not-a-Number (NaN) value of type RatNum
  - ZERO
```
public static final RatNum ZERO
```
    A constant holding a zero value of type RatNum
- Constructor Detail
  - RatNum
```
public RatNum(int n)
```
    Parameters:
    
    n - the value of the new RatNum
    
    Effects:
    Constructs a new RatNum = n.
  - RatNum
```
public RatNum(int n,
              int d)
```
    Parameters:
    
    n - the numerator of the new RatNum
    
    d - the denominator of the new RatNum
    
    Effects:
    If d = 0, constructs a new RatNum = NaN. Else constructs a new RatNum = (n / d).
- Method Detail
  - isNaN
```
public boolean isNaN()
```
    Returns true if this is NaN
    
    Returns:
    
    true iff this is NaN (not-a-number)
  - isNegative
```
public boolean isNegative()
```
    Returns true if this is negative.
    
    Returns:
    
    true iff this < 0
  - isPositive
```
public boolean isPositive()
```
    Returns true if this is positive.
    
    Returns:
    
    true iff this > 0
  - compareTo
```
public int compareTo(RatNum rn)
```
    Compares two RatNums.
    
    Specified by:
    
    compareTo in interface java.lang.Comparable<RatNum>
    
    Parameters:
    
    rn - the RatNum to be compared
    
    Returns:
    
    a negative number if this < rn, 0 if this = rn, a positive number if this > rn
    
    Requires:
    rn != null
  - doubleValue
```
public double doubleValue()
```
    Approximates the value of this rational.
    
    Specified by:
    
    doubleValue in class java.lang.Number
    
    Returns:
    
    a double approximation for this. Note that "NaN" is mapped to Double.NaN, and the Double.NaN value is treated in a special manner by several arithmetic operations, such as the comparison and equality operators. See the Java Language Specification, section 4.2.3, for more details.
  - intValue
```
public int intValue()
```
    Returns an integer approximation for this. The rational number is rounded to the nearest integer.
    
    Specified by:
    
    intValue in class java.lang.Number
  - floatValue
```
public float floatValue()
```
    Returns a float approximation for this. This method is specified by our superclass, Number.
    
    Specified by:
    
    floatValue in class java.lang.Number
  - longValue
```
public long longValue()
```
    Returns a long approximation for this. This method is specified by our superclass, Number. The value returned is rounded to the nearest long.
    
    Specified by:
    
    longValue in class java.lang.Number
  - negate
```
public RatNum negate()
```
    Returns the additive inverse of this RatNum.
    
    Returns:
    
    a Rational equal to (0 - this)
  - add
```
public RatNum add(RatNum arg)
```
    Addition operation.
    
    Parameters:
    
    arg - the other value to be added
    
    Returns:
    
    a RatNum equal to (this + arg). If either argument is NaN, then returns NaN.
    
    Requires:
    arg != null
  - sub
```
public RatNum sub(RatNum arg)
```
    Subtraction operation.
    
    Parameters:
    
    arg - the value to be subtracted
    
    Returns:
    
    a RatNum equal to (this - arg). If either argument is NaN, then returns NaN.
    
    Requires:
    arg != null
  - mul
```
public RatNum mul(RatNum arg)
```
    Multiplication operation.
    
    Parameters:
    
    arg - the other value to be multiplied
    
    Returns:
    
    a RatNum equal to (this * arg). If either argument is NaN, then returns NaN.
    
    Requires:
    arg != null
  - div
```
public RatNum div(RatNum arg)
```
    Division operation.
    
    Parameters:
    
    arg - the divisor
    
    Returns:
    
    a RatNum equal to (this / arg). If arg is zero, or if either argument is NaN, then returns NaN.
    
    Requires:
    arg != null
  - hashCode
```
public int hashCode()
```
    Standard hashCode function.
    
    Overrides:
    
    hashCode in class java.lang.Object
    
    Returns:
    
    an int that all objects equal to this will also return
  - equals
```
public boolean equals(java.lang.Object obj)
```
    Standard equality operation.
    
    Overrides:
    
    equals in class java.lang.Object
    
    Parameters:
    
    obj - the object to be compared for equality
    
    Returns:
    
    true if and only if 'obj' is an instance of a RatNum and 'this' and 'obj' represent the same rational number. Note that NaN = NaN for RatNums.
  - toString
```
public java.lang.String toString()
```
    Overrides:
    
    toString in class java.lang.Object
    
    Returns:
    
    a String representing this, in reduced terms. The returned string will either be "NaN", or it will take on either of the forms "N" or "N/M", where N and M are both integers in decimal notation and M != 0.
  - valueOf
```
public static RatNum valueOf(java.lang.String ratStr)
```
    Makes a RatNum from a string describing it.
    Parameters:
    
    ratStr - a string of the format described in the @spec.requires clause.
    
    Returns:
    
    NaN if ratStr = "NaN". Else returns a RatNum r = ( N / M ), letting M be 1 in the case where only "N" is passed in.
    
    Requires:
    'ratStr' is an instance of a string, with no spaces, of the form:
    
    "NaN"
    "N/M", where N and M are both integers in decimal notation, and M != 0, or
    "N", where N is an integer in decimal notation.

Class RatNum

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Number

Methods inherited from class java.lang.Object

Field Detail

NaN

ZERO

Constructor Detail

RatNum

RatNum

Method Detail

isNaN

isNegative

isPositive

compareTo

doubleValue

intValue

floatValue

longValue

negate

add

sub

mul

div

hashCode

equals

toString

valueOf