com.github.kiprobinson.bigfraction

Enum DivisionMode

java.lang.Object

java.lang.Enum<DivisionMode>

com.github.kiprobinson.bigfraction.DivisionMode

All Implemented Interfaces:

Serializable, Comparable<DivisionMode>

public enum DivisionMode
extends Enum<DivisionMode>

Representation of methods of performing Euclidean division--dividing to an integer and obtaining a remainder. The division methods are all the same when dividend and divisor are positive, but they differ when one or both values are negative.

Given the division problem a/b, all methods produce integer quotient q and remainder r, with 0 <= r < b, fulfilling the equations:

a/b = q + r/b
a = b*q + r
r = a - b*q

More information available at https://en.wikipedia.org/wiki/Modulo_operation.

Enum Constant Summary

Enum Constants

Enum Constant and Description
EUCLIDEAN Euclidean division chooses a quotient which will ensure that the remainder is always positive.
FLOORED In floored division, the quotient is floored (rounded toward negative infinity).
TRUNCATED In truncated division, the quotient is truncated (rounded toward zero).

Method Summary

Methods

Modifier and Type	Method and Description
static DivisionMode	valueOf(String name) Returns the enum constant of this type with the specified name.
static DivisionMode[]	values() Returns an array containing the constants of this enum type, in the order they are declared.

Methods inherited from class java.lang.Enum

clone, compareTo, equals, finalize, getDeclaringClass, hashCode, name, ordinal, toString, valueOf

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Enum Constant Detail

TRUNCATED

public static final DivisionMode TRUNCATED

In truncated division, the quotient is truncated (rounded toward zero). This is the method used by built-in % operator.

With this method, the remainder will have the same sign as the dividend (a).

q = trunc(a/b) (round toward zero)
r = a - b*q

FLOORED

public static final DivisionMode FLOORED

In floored division, the quotient is floored (rounded toward negative infinity).

With this method, the remainder will have the same sign as the divisor (b)

q = floor(a/b) (round toward negative infinity)
r = a - b*q

EUCLIDEAN

public static final DivisionMode EUCLIDEAN

Euclidean division chooses a quotient which will ensure that the remainder is always positive.

q = sign(b) * floor(a/abs(b))
Or:
b > 0: q = floor(a/b)
b < 0: q = ciel(a/b)

r = a - b*q

Method Detail

values

public static DivisionMode[] values()

Returns an array containing the constants of this enum type, in the order they are declared. This method may be used to iterate over the constants as follows:

for (DivisionMode c : DivisionMode.values())
    System.out.println(c);

Returns:

an array containing the constants of this enum type, in the order they are declared

valueOf

public static DivisionMode valueOf(String name)

Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)

Parameters:

name - the name of the enum constant to be returned.

Returns:

the enum constant with the specified name

Throws:

IllegalArgumentException - if this enum type has no constant with the specified name

NullPointerException - if the argument is null