org.spaceroots.mantissa.algebra
Class Polynomial.Double

java.lang.Object
  org.spaceroots.mantissa.algebra.Polynomial
      org.spaceroots.mantissa.algebra.Polynomial.Double

All Implemented Interfaces:

Serializable

Enclosing class:

Polynomial

public static class Polynomial.Double

extends Polynomial

This class implements polynomials with one unknown and real coefficients.

See Also:

Serialized Form

Nested Class Summary

Nested classes inherited from class org.spaceroots.mantissa.algebra.Polynomial

Polynomial.DivisionResult, Polynomial.Double, Polynomial.Rational

Field Summary

protected double[]

a Coefficients array.

Constructor Summary

Polynomial.Double()
Simple constructor.

Polynomial.Double(double value)
Simple constructor.

Polynomial.Double(double[] a)
Simple constructor.

Polynomial.Double(double a1, double a0)
Simple constructor.

Polynomial.Double(double a2, double a1, double a0)
Simple constructor.

Polynomial.Double(double a3, double a2, double a1, double a0)
Simple constructor.

Polynomial.Double(double c, int degree)
Simple constructor.

Polynomial.Double(long value)
Simple constructor.

Polynomial.Double(long a1, long a0)
Simple constructor.

Polynomial.Double(long a2, long a1, long a0)
Simple constructor.

Polynomial.Double(long a3, long a2, long a1, long a0)
Simple constructor.

Polynomial.Double(Polynomial.Rational r)
Simple constructor.

Method Summary

Polynomial.Double	add(Polynomial.Double p) Add a polynomial to the instance
double[]	getCoefficients() Get the coefficients of the polynomial.
int	getDegree() Get the polynomial degree.
Polynomial	getDerivative() Get the derivative of the instance with respect to the unknown.
boolean	isIdentity() Check if the instance is the identity polynomial.
boolean	isOne() Check if the instance is the constant unit polynomial.
boolean	isZero() Check if the instance is the null polynomial.
Polynomial	multiply(double r) Multiply the instance by a constant.
Polynomial	multiply(long l) Multiply the instance by a constant.
Polynomial.Double	multiply(Polynomial.Double p) Multiply the instance by a polynomial.
Polynomial	multiply(RationalNumber r) Multiply the instance by a constant.
Polynomial	negate() Negate the instance.
Polynomial.Double	subtract(Polynomial.Double p) Subtract a polynomial from the instance.
String	toString() Returns a string representation of the polynomial.
double	valueAt(double x) Get the value of the polynomial for a specified unknown.

Methods inherited from class org.spaceroots.mantissa.algebra.Polynomial

divide, divide, divide, multiply

Methods inherited from class java.lang.Object

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

Field Detail

a

protected double[] a

Coefficients array.

Constructor Detail

Polynomial.Double

public Polynomial.Double()

Simple constructor. Build a null polynomial

Polynomial.Double

public Polynomial.Double(long value)

Simple constructor. Build a constant polynomial

Parameters:

value - constant value of the polynomial

Polynomial.Double

public Polynomial.Double(double value)

Simple constructor. Build a constant polynomial

Parameters:

value - constant value of the polynomial

Polynomial.Double

public Polynomial.Double(long a1,
                         long a0)

Simple constructor. Build a first degree polynomial

Parameters:

a1 - leeding degree coefficient

a0 - constant term

Polynomial.Double

public Polynomial.Double(double a1,
                         double a0)

Simple constructor. Build a first degree polynomial

Parameters:

a1 - leeding degree coefficient

a0 - constant term

Polynomial.Double

public Polynomial.Double(long a2,
                         long a1,
                         long a0)

Simple constructor. Build a second degree polynomial

Parameters:

a2 - leeding degree coefficient

a1 - first degree coefficient

a0 - constant term

Polynomial.Double

public Polynomial.Double(double a2,
                         double a1,
                         double a0)

Simple constructor. Build a second degree polynomial

Parameters:

a2 - leeding degree coefficient

a1 - first degree coefficient

a0 - constant term

Polynomial.Double

public Polynomial.Double(long a3,
                         long a2,
                         long a1,
                         long a0)

Simple constructor. Build a third degree polynomial

Parameters:

a3 - leeding degree coefficient

a2 - second degree coefficient

a1 - first degree coefficient

a0 - constant term

Polynomial.Double

public Polynomial.Double(double a3,
                         double a2,
                         double a1,
                         double a0)

Simple constructor. Build a third degree polynomial

Parameters:

a3 - leeding degree coefficient

a2 - second degree coefficient

a1 - first degree coefficient

a0 - constant term

Polynomial.Double

public Polynomial.Double(double[] a)

Simple constructor. Build a polynomial from its coefficients

Parameters:

a - coefficients array, the a[0] array element is the constant term while the a[a.length-1] element is the leeding degree coefficient. The array is copied in a new array, so it can be changed once the constructor as returned.

Polynomial.Double

public Polynomial.Double(double c,
                         int degree)

Simple constructor. Build a one term polynomial from one coefficient and the corresponding degree

Parameters:

c - coefficient

degree - degree associated with the coefficient

Polynomial.Double

public Polynomial.Double(Polynomial.Rational r)

Simple constructor. Build a Polynomial.Double from a Polynomial.Rational

Parameters:

r - a rational polynomial

Method Detail

isZero

public boolean isZero()

Check if the instance is the null polynomial.

Specified by:

isZero in class Polynomial

Returns:

true if the polynomial is null

isOne

public boolean isOne()

Check if the instance is the constant unit polynomial.

Specified by:

isOne in class Polynomial

Returns:

true if the polynomial is the constant unit polynomial

isIdentity

public boolean isIdentity()

Check if the instance is the identity polynomial.

Specified by:

isIdentity in class Polynomial

Returns:

true if the polynomial is the identity polynomial

getDegree

public int getDegree()

Get the polynomial degree.

Specified by:

getDegree in class Polynomial

Returns:

degree

getCoefficients

public double[] getCoefficients()

Get the coefficients of the polynomial.

Returns:

a copy of the coefficients array, the array element at index 0 is the constant term while the element at index a.length-1 is the leading degree coefficient

add

public Polynomial.Double add(Polynomial.Double p)

Add a polynomial to the instance

Parameters:

p - polynomial to add

Returns:

a new polynomial which is the sum of the instance and p

subtract

public Polynomial.Double subtract(Polynomial.Double p)

Subtract a polynomial from the instance.

Parameters:

p - polynomial to subtract

Returns:

a new polynomial which is the difference the instance minus p

negate

public Polynomial negate()

Negate the instance.

Specified by:

negate in class Polynomial

Returns:

a new polynomial

multiply

public Polynomial.Double multiply(Polynomial.Double p)

Multiply the instance by a polynomial.

Parameters:

p - polynomial to multiply by

Returns:

a new polynomial

multiply

public Polynomial multiply(long l)

Multiply the instance by a constant.

Specified by:

multiply in class Polynomial

Parameters:

l - constant to multiply by

Returns:

a new polynomial

multiply

public Polynomial multiply(RationalNumber r)

Multiply the instance by a constant.

Specified by:

multiply in class Polynomial

Parameters:

r - constant to multiply by

Returns:

a new polynomial

multiply

public Polynomial multiply(double r)

Multiply the instance by a constant.

Parameters:

r - constant to multiply by

Returns:

a new polynomial

valueAt

public double valueAt(double x)

Get the value of the polynomial for a specified unknown.

Specified by:

valueAt in class Polynomial

Parameters:

x - value of the unknown

Returns:

value of the polynomial

getDerivative

public Polynomial getDerivative()

Get the derivative of the instance with respect to the unknown. The derivative of a n degree polynomial is a n-1 degree polynomial of the same type.

Specified by:

getDerivative in class Polynomial

Returns:

a new polynomial which is the derivative of the instance

toString

public String toString()

Returns a string representation of the polynomial.

The representation is user oriented. Terms are displayed lowest degrees first. The multiplications signs, coefficients equals to one and null terms are not displayed (except if the polynomial is 0, in which case the 0 constant term is displayed). Addition of terms with negative coefficients are replaced by subtraction of terms with positive coefficients except for the first displayed term (i.e. we display -3 for a constant negative polynomial, but 1 - 3 x + x^2 if the negative coefficient is not the first one displayed).

Returns:

a string representation of the polynomial