Package edu.jas.arith

Class BigDecimal

java.lang.Object

edu.jas.arith.BigDecimal

All Implemented Interfaces:

Rational, AbelianGroupElem<BigDecimal>, AbelianGroupFactory<BigDecimal>, Element<BigDecimal>, ElemFactory<BigDecimal>, GcdRingElem<BigDecimal>, MonoidElem<BigDecimal>, MonoidFactory<BigDecimal>, RingElem<BigDecimal>, RingFactory<BigDecimal>, java.io.Serializable, java.lang.Comparable<BigDecimal>

public final class BigDecimal
extends java.lang.Object
implements GcdRingElem<BigDecimal>, RingFactory<BigDecimal>, Rational

BigDecimal class to make java.math.BigDecimal available with RingElem interface. Objects of this class are immutable. Experimental, use with care, compareTo is some times hacked.

Author:

Heinz Kredel

See Also:

BigDecimal, Serialized Form

Field Summary

Fields

Modifier and Type	Field	Description
java.math.MathContext	context
static java.math.MathContext	DEFAULT_CONTEXT
static int	DEFAULT_PRECISION
static boolean	EXACT_EQUAL	If true, then use equals from java.math.BigDecimal, else use hacked approximate compareTo().
static BigDecimal	ONE	The constant 1.
java.math.BigDecimal	val	The data structure.
static BigDecimal	ZERO	The constant 0.

Constructor Summary

Constructors

Constructor	Description
BigDecimal()	Constructor for BigDecimal without parameters.
BigDecimal(double a)	Constructor for BigDecimal from double.
BigDecimal(double a, java.math.MathContext mc)	Constructor for BigDecimal from double and a context.
BigDecimal(long a)	Constructor for BigDecimal from long.
BigDecimal(long a, java.math.MathContext mc)	Constructor for BigDecimal from long and a context.
BigDecimal(BigRational a)	Constructor for BigDecimal from BigRational.
BigDecimal(BigRational a, java.math.MathContext mc)	Constructor for BigDecimal from BigRational.
BigDecimal(java.lang.String s)	Constructor for BigDecimal from String.
BigDecimal(java.lang.String s, java.math.MathContext mc)	Constructor for BigDecimal from String.
BigDecimal(java.math.BigDecimal a)	Constructor for BigDecimal from math.BigDecimal.
BigDecimal(java.math.BigDecimal a, java.math.MathContext mc)	Constructor for BigDecimal from math.BigDecimal.
BigDecimal(java.math.BigInteger a)	Constructor for BigDecimal from java.math.BigInteger.
BigDecimal(java.math.BigInteger a, java.math.MathContext mc)	Constructor for BigDecimal from java.math.BigInteger.

Method Summary

Modifier and Type	Method	Description
BigDecimal	abs()	Absolute value of this.
long	bitLength()	Returns the number of bits in the representation of this BigDecimal, including a sign bit.
java.math.BigInteger	characteristic()	Characteristic of this ring.
int	compareTo(BigDecimal b)	Compare to BigDecimal b.
int	compareToAbsolute(BigDecimal b)	Compare absolute to BigDecimal b.
int	compareToRelative(BigDecimal b)	Compare to relative BigDecimal b.
BigDecimal	copy()	Clone this.
BigDecimal	copy(BigDecimal c)	Copy BigDecimal element c.
BigDecimal	divide(BigDecimal S)	BigDecimal divide.
double	doubleValue()	Get this decimal as a double.
BigDecimal[]	egcd(BigDecimal S)	BigDecimal extended greatest common divisor.
boolean	equals(java.lang.Object b)	Comparison with any other object.
BigDecimal	factory()	Get the corresponding element factory.
BigDecimal	fromInteger(long a)	Get a BigDecimal element from long.
BigDecimal	fromInteger(java.math.BigInteger a)	Get a BigDecimal element from a math.BigDecimal.
BigDecimal	gcd(BigDecimal S)	BigDecimal greatest common divisor.
java.util.List<BigDecimal>	generators()	Get a list of the generating elements.
BigDecimal	getDecimal()	Get the decimal representation.
BigDecimal	getONE()	Get the one element.
BigRational	getRational()	Get the rational representation.
BigDecimal	getZERO()	Get the zero element.
int	hashCode()	Hash code for this BigDecimal.
BigDecimal	inverse()	Integer inverse.
boolean	isAssociative()	Query if this ring is associative.
boolean	isCommutative()	Query if this ring is commutative.
boolean	isField()	Query if this ring is a field.
boolean	isFinite()	Is this structure finite or infinite.
boolean	isONE()	Is BigDecimal number one.
boolean	isUnit()	Is BigDecimal number unit.
boolean	isZERO()	Is BigDecimal number zero.
BigDecimal	multiply(BigDecimal S)	BigDecimal multiply.
BigDecimal	negate()	Negate this.
BigDecimal	parse(java.io.Reader r)	BigDecimal parse from Reader.
BigDecimal	parse(java.lang.String s)	BigDecimal parse from String.
BigDecimal[]	quotientRemainder(BigDecimal S)	BigDecimal compute quotient and remainder.
BigDecimal	random(int n)	BigDecimal random.
BigDecimal	random(int n, int e)	BigDecimal random.
BigDecimal	random(int n, int e, java.util.Random rnd)	BigDecimal random.
BigDecimal	random(int n, java.util.Random rnd)	BigDecimal random.
BigDecimal	remainder(BigDecimal S)	BigDecimal remainder.
int	signum()	signum.
BigDecimal	subtract(BigDecimal S)	BigDecimal subtract.
BigDecimal	sum(BigDecimal S)	BigDecimal summation.
java.lang.String	toScript()	Get a scripting compatible string representation.
java.lang.String	toScriptFactory()	Get a scripting compatible string representation of the factory.
java.lang.String	toString()	Get the String representation.
static BigDecimal	valueOf(long a)	Get a BigDecimal element from long.
static BigDecimal	valueOf(java.math.BigDecimal a)	Get a BigDecimal element from a math.BigDecimal.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface edu.jas.structure.ElemFactory

valueOf

Methods inherited from interface edu.jas.structure.MonoidElem

leftDivide, leftRemainder, power, rightDivide, rightRemainder, twosidedDivide, twosidedRemainder

Methods inherited from interface edu.jas.structure.RingElem

leftGcd, rightGcd

Field Detail

val

public final java.math.BigDecimal val

The data structure.

DEFAULT_CONTEXT

public static final java.math.MathContext DEFAULT_CONTEXT

DEFAULT_PRECISION

public static final int DEFAULT_PRECISION

context

public final java.math.MathContext context

EXACT_EQUAL

public static final boolean EXACT_EQUAL

If true, then use equals from java.math.BigDecimal, else use hacked approximate compareTo().

See Also:

Constant Field Values

ZERO

public static final BigDecimal ZERO

The constant 0.

ONE

public static final BigDecimal ONE

The constant 1.

Constructor Detail

BigDecimal

public BigDecimal(java.math.BigDecimal a)

Constructor for BigDecimal from math.BigDecimal.

Parameters:

a - java.math.BigDecimal.

BigDecimal

public BigDecimal(java.math.BigDecimal a,
                  java.math.MathContext mc)

Constructor for BigDecimal from math.BigDecimal.

Parameters:

a - java.math.BigDecimal.

mc - MathContext.

BigDecimal

public BigDecimal(long a)

Constructor for BigDecimal from long.

Parameters:

a - long.

BigDecimal

public BigDecimal(long a,
                  java.math.MathContext mc)

Constructor for BigDecimal from long and a context.

Parameters:

a - long.

mc - MathContext.

BigDecimal

public BigDecimal(double a)

Constructor for BigDecimal from double.

Parameters:

a - double.

BigDecimal

public BigDecimal(double a,
                  java.math.MathContext mc)

Constructor for BigDecimal from double and a context.

Parameters:

a - double.

mc - MathContext.

BigDecimal

public BigDecimal(java.math.BigInteger a)

Constructor for BigDecimal from java.math.BigInteger.

Parameters:

a - java.math.BigInteger.

BigDecimal

public BigDecimal(java.math.BigInteger a,
                  java.math.MathContext mc)

Constructor for BigDecimal from java.math.BigInteger.

Parameters:

a - java.math.BigInteger.

mc - MathContext.

BigDecimal

public BigDecimal(BigRational a)

Constructor for BigDecimal from BigRational.

Parameters:

a - edu.jas.arith.BigRational.

BigDecimal

public BigDecimal(BigRational a,
                  java.math.MathContext mc)

Constructor for BigDecimal from BigRational.

Parameters:

a - edu.jas.arith.BigRational.

mc - MathContext.

BigDecimal

public BigDecimal(java.lang.String s)

Constructor for BigDecimal from String.

Parameters:

s - String.

BigDecimal

public BigDecimal(java.lang.String s,
                  java.math.MathContext mc)

Constructor for BigDecimal from String.

Parameters:

s - String.

mc - MathContext.

BigDecimal

public BigDecimal()

Constructor for BigDecimal without parameters.

Method Detail

factory

public BigDecimal factory()

Get the corresponding element factory.

Specified by:

factory in interface Element<BigDecimal>

Returns:

factory for this Element.

See Also:

Element.factory()

generators

public java.util.List<BigDecimal> generators()

Get a list of the generating elements.

Specified by:

generators in interface ElemFactory<BigDecimal>

Returns:

list of generators for the algebraic structure.

See Also:

ElemFactory.generators()

isFinite

public boolean isFinite()

Is this structure finite or infinite.

Specified by:

isFinite in interface ElemFactory<BigDecimal>

Returns:

true if this structure is finite, else false.

See Also:

Note: is actually finite but returns false.

copy

public BigDecimal copy()

Clone this.

Specified by:

copy in interface Element<BigDecimal>

Returns:

Creates and returns a copy of this Element.

See Also:

Object.clone()

copy

public BigDecimal copy(BigDecimal c)

Copy BigDecimal element c.

Specified by:

copy in interface ElemFactory<BigDecimal>

Parameters:

c - BigDecimal.

Returns:

a copy of c.

getZERO

public BigDecimal getZERO()

Get the zero element.

Specified by:

getZERO in interface AbelianGroupFactory<BigDecimal>

Returns:

0.

getONE

public BigDecimal getONE()

Get the one element.

Specified by:

getONE in interface MonoidFactory<BigDecimal>

Returns:

1.

getDecimal

public BigDecimal getDecimal()

Get the decimal representation.

Returns:

decimal.

getRational

public BigRational getRational()

Get the rational representation.

Specified by:

getRational in interface Rational

Returns:

rational number.

isCommutative

public boolean isCommutative()

Query if this ring is commutative.

Specified by:

isCommutative in interface MonoidFactory<BigDecimal>

Returns:

true.

isAssociative

public boolean isAssociative()

Query if this ring is associative. Floating point number addition is not associative, but multiplication is.

Specified by:

isAssociative in interface MonoidFactory<BigDecimal>

Returns:

true.

isField

public boolean isField()

Query if this ring is a field.

Specified by:

isField in interface RingFactory<BigDecimal>

Returns:

true.

characteristic

public java.math.BigInteger characteristic()

Characteristic of this ring.

Specified by:

characteristic in interface RingFactory<BigDecimal>

Returns:

characteristic of this ring.

fromInteger

public BigDecimal fromInteger(java.math.BigInteger a)

Get a BigDecimal element from a math.BigDecimal.

Specified by:

fromInteger in interface ElemFactory<BigDecimal>

Parameters:

a - math.BigDecimal.

Returns:

a as BigDecimal.

valueOf

public static BigDecimal valueOf(java.math.BigDecimal a)

Get a BigDecimal element from a math.BigDecimal.

Parameters:

a - math.BigDecimal.

Returns:

a as BigDecimal.

fromInteger

public BigDecimal fromInteger(long a)

Get a BigDecimal element from long.

Specified by:

fromInteger in interface ElemFactory<BigDecimal>

Parameters:

a - long.

Returns:

a as BigDecimal.

valueOf

public static BigDecimal valueOf(long a)

Get a BigDecimal element from long.

Parameters:

a - long.

Returns:

a as BigDecimal.

isZERO

public boolean isZERO()

Is BigDecimal number zero.

Specified by:

isZERO in interface AbelianGroupElem<BigDecimal>

Returns:

If this is 0 then true is returned, else false.

See Also:

AbelianGroupElem.isZERO()

isONE

public boolean isONE()

Is BigDecimal number one.

Specified by:

isONE in interface MonoidElem<BigDecimal>

Returns:

true if this is 1, else false.

See Also:

MonoidElem.isONE()

isUnit

public boolean isUnit()

Is BigDecimal number unit.

Specified by:

isUnit in interface MonoidElem<BigDecimal>

Returns:

true if this is a unit, else false.

See Also:

MonoidElem.isUnit()

toString

public java.lang.String toString()

Get the String representation.

Overrides:

toString in class java.lang.Object

See Also:

Object.toString()

doubleValue

public double doubleValue()

Get this decimal as a double.

Returns:

the decimal as a double

See Also:

Number.doubleValue()

toScript

public java.lang.String toScript()

Get a scripting compatible string representation.

Specified by:

toScript in interface Element<BigDecimal>

Specified by:

toScript in interface ElemFactory<BigDecimal>

Returns:

script compatible representation for this Element.

See Also:

Element.toScript()

toScriptFactory

public java.lang.String toScriptFactory()

Get a scripting compatible string representation of the factory.

Specified by:

toScriptFactory in interface Element<BigDecimal>

Returns:

script compatible representation for this ElemFactory.

See Also:

Element.toScriptFactory()

compareTo

public int compareTo(BigDecimal b)

Compare to BigDecimal b. Experimental, is hacked.

Specified by:

compareTo in interface java.lang.Comparable<BigDecimal>

Specified by:

compareTo in interface Element<BigDecimal>

Parameters:

b - BigDecimal.

Returns:

0 if abs(this-b) < epsilon, 1 if this > b, -1 if this < b.

compareToAbsolute

public int compareToAbsolute(BigDecimal b)

Compare absolute to BigDecimal b. Experimental, is hacked.

Parameters:

b - BigDecimal.

Returns:

0 if abs(this-b) < epsilon, 1 if this > b, -1 if this < b.

compareToRelative

public int compareToRelative(BigDecimal b)

Compare to relative BigDecimal b. Experimental, is hacked.

Parameters:

b - BigDecimal.

Returns:

0 if abs(this-b)/max(this,b) < epsilon, 1 if this > b, -1 if this < b.

equals

public boolean equals(java.lang.Object b)

Comparison with any other object.

Specified by:

equals in interface Element<BigDecimal>

Overrides:

equals in class java.lang.Object

Returns:

true if this is equal to b, else false.

See Also:

Object.equals(java.lang.Object)

hashCode

public int hashCode()

Hash code for this BigDecimal.

Specified by:

hashCode in interface Element<BigDecimal>

Overrides:

hashCode in class java.lang.Object

Returns:

the hashCode.

See Also:

Object.hashCode()

abs

public BigDecimal abs()

Absolute value of this.

Specified by:

abs in interface AbelianGroupElem<BigDecimal>

Returns:

|this|.

See Also:

AbelianGroupElem.abs()

negate

public BigDecimal negate()

Description copied from interface: AbelianGroupElem

Negate this.

Specified by:

negate in interface AbelianGroupElem<BigDecimal>

Returns:

- this.

signum

public int signum()

signum.

Specified by:

signum in interface AbelianGroupElem<BigDecimal>

Returns:

the sign of this.

See Also:

AbelianGroupElem.signum()

subtract

public BigDecimal subtract(BigDecimal S)

BigDecimal subtract.

Specified by:

subtract in interface AbelianGroupElem<BigDecimal>

Parameters:

S - BigDecimal.

Returns:

this-S.

divide

public BigDecimal divide(BigDecimal S)

BigDecimal divide.

Specified by:

divide in interface MonoidElem<BigDecimal>

Parameters:

S - BigDecimal.

Returns:

this/S.

inverse

public BigDecimal inverse()

Integer inverse. R is a non-zero integer. S=1/R if defined else 0.

Specified by:

inverse in interface MonoidElem<BigDecimal>

Returns:

x with this * x = 1, if it exists.

See Also:

MonoidElem.inverse()

remainder

public BigDecimal remainder(BigDecimal S)

BigDecimal remainder.

Specified by:

remainder in interface MonoidElem<BigDecimal>

Parameters:

S - BigDecimal.

Returns:

this - (this/S)*S.

quotientRemainder

public BigDecimal[] quotientRemainder(BigDecimal S)

BigDecimal compute quotient and remainder.

Specified by:

quotientRemainder in interface MonoidElem<BigDecimal>

Parameters:

S - BigDecimal.

Returns:

BigDecimal[] { q, r } with q = this/S and r = rem(this,S).

gcd

public BigDecimal gcd(BigDecimal S)

BigDecimal greatest common divisor.

Specified by:

gcd in interface RingElem<BigDecimal>

Parameters:

S - BigDecimal.

Returns:

gcd(this,S).

egcd

public BigDecimal[] egcd(BigDecimal S)

BigDecimal extended greatest common divisor.

Specified by:

egcd in interface RingElem<BigDecimal>

Parameters:

S - BigDecimal.

Returns:

[ gcd(this,S), a, b ] with a*this + b*S = gcd(this,S).

random

public BigDecimal random(int n)

BigDecimal random.

Specified by:

random in interface ElemFactory<BigDecimal>

Parameters:

n - such that 0 ≤ val(r) ≤ (2ⁿ-1). 0 ≤ exp(r) ≤ (10-1).

Returns:

r, a random BigDecimal.

random

public BigDecimal random(int n,
                         java.util.Random rnd)

BigDecimal random.

Specified by:

random in interface ElemFactory<BigDecimal>

Parameters:

n - such that 0 ≤ val(r) ≤ (2ⁿ-1). 0 ≤ exp(r) ≤ (10-1).

rnd - is a source for random bits.

Returns:

r, a random BigDecimal.

random

public BigDecimal random(int n,
                         int e)

BigDecimal random.

Parameters:

n - such that 0 ≤ val(r) ≤ (2ⁿ-1).

e - such that 0 ≤ exp(r) ≤ (e-1).

Returns:

r, a random BigDecimal.

random

public BigDecimal random(int n,
                         int e,
                         java.util.Random rnd)

BigDecimal random.

Parameters:

n - such that 0 ≤ val(r) ≤ (2ⁿ-1).

e - such that 0 ≤ exp(r) ≤ (e-1).

rnd - is a source for random bits.

Returns:

r, a random BigDecimal.

multiply

public BigDecimal multiply(BigDecimal S)

BigDecimal multiply.

Specified by:

multiply in interface MonoidElem<BigDecimal>

Parameters:

S - BigDecimal.

Returns:

this*S.

sum

public BigDecimal sum(BigDecimal S)

BigDecimal summation.

Specified by:

sum in interface AbelianGroupElem<BigDecimal>

Parameters:

S - BigDecimal.

Returns:

this+S.

parse

public BigDecimal parse(java.lang.String s)

BigDecimal parse from String.

Specified by:

parse in interface ElemFactory<BigDecimal>

Parameters:

s - String.

Returns:

Biginteger from s.

parse

public BigDecimal parse(java.io.Reader r)

BigDecimal parse from Reader.

Specified by:

parse in interface ElemFactory<BigDecimal>

Parameters:

r - Reader.

Returns:

next Biginteger from r.

bitLength

public long bitLength()

Returns the number of bits in the representation of this BigDecimal, including a sign bit. For positive BigDecimal, this is equivalent to val.unscaledValue().bitLength().)

Returns:

number of bits in the representation of this BigDecimal, including a sign bit.