Module ojalgo

Package org.ojalgo.scalar

Class ExactDecimal<S extends ExactDecimal<S>>

java.lang.Object

org.ojalgo.scalar.ExactDecimal<S>

All Implemented Interfaces:

java.lang.Comparable<S>, Field<Scalar<S>>, Group, Group.Additive<Scalar<S>>, Group.Multiplicative<Scalar<S>>, NormedVectorSpace<Scalar<S>,S>, Operation, Operation.Addition<Scalar<S>>, Operation.Division<Scalar<S>>, Operation.Multiplication<Scalar<S>>, Operation.Subtraction<Scalar<S>>, Ring<Scalar<S>>, ScalarOperation, ScalarOperation.Addition<Scalar<S>,S>, ScalarOperation.Division<Scalar<S>,S>, ScalarOperation.Multiplication<Scalar<S>,S>, ScalarOperation.Subtraction<Scalar<S>,S>, VectorSpace<Scalar<S>,S>, Scalar<S>, SelfDeclaringScalar<S>, AccessScalar<S>, Tensor<S,Scalar<S>>, NumberContext.Enforceable<S>, NumberDefinition

Direct Known Subclasses:

Amount, Money, Price, Quantity

public abstract class ExactDecimal<S extends ExactDecimal<S>>
extends java.lang.Object
implements SelfDeclaringScalar<S>

To help implement exact decimal numbers with a fixed number of decimal places (fixed scale).

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	ExactDecimal.Descriptor
static interface	ExactDecimal.Factory<S extends ExactDecimal<S>>

Nested classes/interfaces inherited from interface org.ojalgo.algebra.Group

Group.Additive<T>, Group.Multiplicative<T>

Nested classes/interfaces inherited from interface org.ojalgo.algebra.Operation

Operation.Addition<T>, Operation.Division<T>, Operation.Multiplication<T>, Operation.Subtraction<T>

Nested classes/interfaces inherited from interface org.ojalgo.algebra.ScalarOperation

ScalarOperation.Addition<T,N extends java.lang.Comparable<N>>, ScalarOperation.Division<T,N extends java.lang.Comparable<N>>, ScalarOperation.Multiplication<T,N extends java.lang.Comparable<N>>, ScalarOperation.Subtraction<T,N extends java.lang.Comparable<N>>

Field Summary

Fields

Modifier and Type	Field	Description
private java.math.BigDecimal	myDecimal
private long	myNumerator

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	ExactDecimal(long numerator)

Method Summary

Modifier and Type	Method	Description
S	add(double scalarAddend)
S	add(S scalarAddend)
int	compareTo(S reference)
S	conjugate()	This method will (most likely) be moved to some other interface in the future! Just have to figure out where it fits...
protected abstract ExactDecimal.Descriptor	descriptor()
S	divide(double scalarDivisor)
S	divide(S scalarDivisor)
double	doubleValue()
S	enforce(NumberContext context)
protected static long	extractUnscaledValue(java.math.BigDecimal decimal, NumberContext cntxt)
float	floatValue()
S	get()
int	intValue()
S	invert()	The multiplicative inverse.
boolean	isAbsolute()
boolean	isSmall(double comparedTo)
boolean	isZero()	Tests if this scalar value is exactly zero.
long	longValue()
S	multiply(double scalarMultiplicand)
S	multiply(S scalarMultiplicand)
S	negate()	The additive inverse of this.
double	norm()	this == this.signum().multiply(this.norm())
(package private) long	numerator()
S	power(int power)	Multiply by itself power times.
S	signum()	this == this.signum().multiply(this.norm())
S	subtract(double scalarSubtrahend)
S	subtract(S scalarSubtrahend)
java.math.BigDecimal	toBigDecimal()
private java.math.BigDecimal	toBigDecimal(NumberContext context)
java.lang.String	toString()
java.lang.String	toString(NumberContext context)
protected abstract S	wrap(long numerator)

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.ojalgo.type.NumberDefinition

booleanValue, byteValue, shortValue

Methods inherited from interface org.ojalgo.scalar.Scalar

add, dimensions, divide, multiply, rank, subtract, toPlainString

Methods inherited from interface org.ojalgo.scalar.SelfDeclaringScalar

add, divide, multiply, subtract

Methods inherited from interface org.ojalgo.tensor.Tensor

components, isSameShape

Field Detail

myDecimal

private transient java.math.BigDecimal myDecimal

myNumerator

private final long myNumerator

Constructor Detail

ExactDecimal

protected ExactDecimal(long numerator)

Method Detail

extractUnscaledValue

protected static long extractUnscaledValue(java.math.BigDecimal decimal,
                                           NumberContext cntxt)

add

public final S add(double scalarAddend)

Specified by:

add in interface ScalarOperation.Addition<Scalar<S extends ExactDecimal<S>>,S extends ExactDecimal<S>>

Specified by:

add in interface SelfDeclaringScalar<S extends ExactDecimal<S>>

Returns:

this + scalarAddend.

add

public final S add(S scalarAddend)

Specified by:

add in interface ScalarOperation.Addition<Scalar<S extends ExactDecimal<S>>,S extends ExactDecimal<S>>

Specified by:

add in interface SelfDeclaringScalar<S extends ExactDecimal<S>>

Returns:

this + scalarAddend.

compareTo

public final int compareTo(S reference)

Specified by:

compareTo in interface java.lang.Comparable<S extends ExactDecimal<S>>

conjugate

public final S conjugate()

Description copied from interface: VectorSpace

This method will (most likely) be moved to some other interface in the future! Just have to figure out where it fits...

The conjugate transpose of a matrix and/or the conjugate of a scalar/field like ComplexNumber or Quaternion.

The conjugate transpose of a real matrix is simply its transpose.

Specified by:

conjugate in interface SelfDeclaringScalar<S extends ExactDecimal<S>>

Specified by:

conjugate in interface VectorSpace<Scalar<S extends ExactDecimal<S>>,S extends ExactDecimal<S>>

divide

public final S divide(double scalarDivisor)

Specified by:

divide in interface ScalarOperation.Division<Scalar<S extends ExactDecimal<S>>,S extends ExactDecimal<S>>

Specified by:

divide in interface SelfDeclaringScalar<S extends ExactDecimal<S>>

Returns:

this / scalarDivisor.

divide

public final S divide(S scalarDivisor)

Specified by:

divide in interface ScalarOperation.Division<Scalar<S extends ExactDecimal<S>>,S extends ExactDecimal<S>>

Specified by:

divide in interface SelfDeclaringScalar<S extends ExactDecimal<S>>

Returns:

this / scalarDivisor.

doubleValue

public final double doubleValue()

Specified by:

doubleValue in interface NumberDefinition

enforce

public final S enforce(NumberContext context)

Specified by:

enforce in interface NumberContext.Enforceable<S extends ExactDecimal<S>>

floatValue

public final float floatValue()

Specified by:

floatValue in interface NumberDefinition

get

public final S get()

Specified by:

get in interface AccessScalar<S extends ExactDecimal<S>>

intValue

public final int intValue()

Specified by:

intValue in interface NumberDefinition

invert

public final S invert()

Description copied from interface: Group.Multiplicative

The multiplicative inverse.

Specified by:

invert in interface Group.Multiplicative<S extends ExactDecimal<S>>

Specified by:

invert in interface SelfDeclaringScalar<S extends ExactDecimal<S>>

Returns:

IDENTITY / this.

isAbsolute

public final boolean isAbsolute()

Specified by:

isAbsolute in interface Scalar<S extends ExactDecimal<S>>

Returns:

true if this is equal to its own norm, modulus or absolute value (non-negative real part and no imaginary part); otherwise false.

See Also:

Scalar.isAbsolute()

isSmall

public final boolean isSmall(double comparedTo)

Specified by:

isSmall in interface NormedVectorSpace<Scalar<S extends ExactDecimal<S>>,S extends ExactDecimal<S>>

Parameters:

comparedTo - What to compare with

Returns:

true if this is small compared to the magnitude of the input reference value.

isZero

public final boolean isZero()

Description copied from interface: Scalar

Tests if this scalar value is exactly zero.

Each implementation should test for zero as exactly as possible based on what's achievable with that specific scalar type. The purpose is NOT to have similar behavior between different implementations, but rather to leverage the full precision and capabilities of each type.

For example:

• Primitive types (like double) should use exact equality comparison
• High-precision types (like Quadruple) should check both base and remainder components
• Arbitrary-precision types (like BigDecimal) should use their built-in zero detection
• Complex types should check both real and imaginary parts

This method should NOT use tolerance-based comparisons or approximate zero detection, as those are better handled by context-aware methods like NormedVectorSpace.isSmall(double).

Specified by:

isZero in interface Scalar<S extends ExactDecimal<S>>

Returns:

true if this scalar represents exactly zero, false otherwise

See Also:

NormedVectorSpace.isSmall(double)

longValue

public final long longValue()

Specified by:

longValue in interface NumberDefinition

multiply

public final S multiply(double scalarMultiplicand)

Specified by:

multiply in interface ScalarOperation.Multiplication<Scalar<S extends ExactDecimal<S>>,S extends ExactDecimal<S>>

Specified by:

multiply in interface SelfDeclaringScalar<S extends ExactDecimal<S>>

Returns:

this * scalarMultiplicand.

multiply

public final S multiply(S scalarMultiplicand)

Specified by:

multiply in interface ScalarOperation.Multiplication<Scalar<S extends ExactDecimal<S>>,S extends ExactDecimal<S>>

Specified by:

multiply in interface SelfDeclaringScalar<S extends ExactDecimal<S>>

Returns:

this * multiplicand.

negate

public final S negate()

Description copied from interface: Group.Additive

The additive inverse of this.

Specified by:

negate in interface Group.Additive<S extends ExactDecimal<S>>

Specified by:

negate in interface SelfDeclaringScalar<S extends ExactDecimal<S>>

Returns:

-this.

norm

public final double norm()

Description copied from interface: NormedVectorSpace

this == this.signum().multiply(this.norm())

Specified by:

norm in interface NormedVectorSpace<Scalar<S extends ExactDecimal<S>>,S extends ExactDecimal<S>>

Returns:

The norm

power

public S power(int power)

Description copied from interface: Operation.Multiplication

Multiply by itself power times.

Specified by:

power in interface Operation.Multiplication<S extends ExactDecimal<S>>

Specified by:

power in interface SelfDeclaringScalar<S extends ExactDecimal<S>>

signum

public final S signum()

Description copied from interface: NormedVectorSpace

this == this.signum().multiply(this.norm())

Specified by:

signum in interface NormedVectorSpace<Scalar<S extends ExactDecimal<S>>,S extends ExactDecimal<S>>

Specified by:

signum in interface SelfDeclaringScalar<S extends ExactDecimal<S>>

Returns:

A unit "vector"

subtract

public final S subtract(double scalarSubtrahend)

Specified by:

subtract in interface ScalarOperation.Subtraction<Scalar<S extends ExactDecimal<S>>,S extends ExactDecimal<S>>

Specified by:

subtract in interface SelfDeclaringScalar<S extends ExactDecimal<S>>

Returns:

this - scalarSubtrahend.

subtract

public final S subtract(S scalarSubtrahend)

Specified by:

subtract in interface ScalarOperation.Subtraction<Scalar<S extends ExactDecimal<S>>,S extends ExactDecimal<S>>

Specified by:

subtract in interface SelfDeclaringScalar<S extends ExactDecimal<S>>

Returns:

this - scalarSubtrahend.

toBigDecimal

public final java.math.BigDecimal toBigDecimal()

Specified by:

toBigDecimal in interface Scalar<S extends ExactDecimal<S>>

toString

public final java.lang.String toString()

Overrides:

toString in class java.lang.Object

toString

public final java.lang.String toString(NumberContext context)

Specified by:

toString in interface Scalar<S extends ExactDecimal<S>>

toBigDecimal

private final java.math.BigDecimal toBigDecimal(NumberContext context)

descriptor

protected abstract ExactDecimal.Descriptor descriptor()

wrap

protected abstract S wrap(long numerator)

numerator

final long numerator()