jsat.math

Class Complex

java.lang.Object

jsat.math.Complex

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable

public class Complex
extends java.lang.Object
implements java.lang.Cloneable, java.io.Serializable

A class for representing a complex value by a real and imaginary double pair.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
Complex(double real, double imag) Creates a new Complex number

Method Summary

Modifier and Type	Method and Description
Complex	add(Complex c) Creates a new complex number containing the resulting addition of this and another
static void	cDiv(double a, double b, double c, double d, double[] results) Performs a complex division operation.
static void	cMul(double a, double b, double c, double d, double[] results) Performs a complex multiplication
Complex	divide(Complex c) Creates a new complex number containing the resulting division of this by another
boolean	equals(java.lang.Object obj)
boolean	equals(java.lang.Object obj, double eps) Checks if this is approximately equal to another Complex object
double	getArg() Computes the Argument, also called phase, of this complex number.
Complex	getConjugate() Returns a new complex number representing the complex conjugate of this one
double	getImag() Returns the imaginary part of this complex number
double	getMagnitude() Computes the magnitude of this complex number, which is sqrt(Re2+Im2)
double	getReal() Returns the real part of this complex number
int	hashCode()
static Complex	I() Returns the complex number representing sqrt(-1)
Complex	multiply(Complex c) Creates a new complex number containing the resulting multiplication between this and another
void	mutableAdd(Complex c) Alters this complex number to contain the result of the addition of another
void	mutableAdd(double r, double i) Alters this complex number as if an addition of another complex number was performed.
void	mutableDivide(Complex c) Alters this complex number to contain the result of the division by another
void	mutableDivide(double c, double d) Alters this complex number as if a division by another complex number was performed.
void	mutableMultiply(Complex c) Alters this complex number to contain the result of the multiplication of another
void	mutableMultiply(double c, double d) Alters this complex number as if a multiplication of another complex number was performed.
void	mutableSubtract(Complex c) Alters this complex number to contain the result of the subtraction of another
void	mutableSubtract(double r, double i) Alters this complex number as if a subtraction of another complex number was performed.
void	mutateConjugate() Alters this complex number so that it represents its complex conjugate instead.
void	setImag(double imag) Sets the imaginary value part of this complex number
void	setReal(double r) Sets the real value part of this complex number
Complex	subtract(Complex c) Creates a new complex number containing the resulting subtracting another from this one
java.lang.String	toString()

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

Complex

public Complex(double real,
               double imag)

Creates a new Complex number

Parameters:

real - the real part of the number

imag - the imaginary part of the number

Method Detail

I

public static Complex I()

Returns the complex number representing sqrt(-1)

Returns:

the complex number i

getReal

public double getReal()

Returns the real part of this complex number

Returns:

the real part of this complex number

setReal

public void setReal(double r)

Sets the real value part of this complex number

Parameters:

r - the new real value

setImag

public void setImag(double imag)

Sets the imaginary value part of this complex number

Parameters:

imag - the new imaginary value

getImag

public double getImag()

Returns the imaginary part of this complex number

Returns:

the imaginary part of this complex number

mutableAdd

public void mutableAdd(double r,
                       double i)

Alters this complex number as if an addition of another complex number was performed.

Parameters:

r - the real part of the other number

i - the imaginary part of the other number

mutableAdd

public void mutableAdd(Complex c)

Alters this complex number to contain the result of the addition of another

Parameters:

c - the complex value to add to this

add

public Complex add(Complex c)

Creates a new complex number containing the resulting addition of this and another

Parameters:

c - the number to add

Returns:

this+c

mutableSubtract

public void mutableSubtract(double r,
                            double i)

Alters this complex number as if a subtraction of another complex number was performed.

Parameters:

r - the real part of the other number

i - the imaginary part of the other number

mutableSubtract

public void mutableSubtract(Complex c)

Alters this complex number to contain the result of the subtraction of another

Parameters:

c - the number to subtract

subtract

public Complex subtract(Complex c)

Creates a new complex number containing the resulting subtracting another from this one

Parameters:

c - the number to subtract

Returns:

this-c

cMul

public static void cMul(double a,
                        double b,
                        double c,
                        double d,
                        double[] results)

Performs a complex multiplication

Parameters:

a - the real part of the first number

b - the imaginary part of the first number

c - the real part of the second number

d - the imaginary part of the second number

results - an array to store the real and imaginary results in. First index is the real, 2nd is the imaginary.

mutableMultiply

public void mutableMultiply(double c,
                            double d)

Alters this complex number as if a multiplication of another complex number was performed.

Parameters:

c - the real part of the other number

d - the imaginary part of the other number

mutableMultiply

public void mutableMultiply(Complex c)

Alters this complex number to contain the result of the multiplication of another

Parameters:

c - the number to multiply by

multiply

public Complex multiply(Complex c)

Creates a new complex number containing the resulting multiplication between this and another

Parameters:

c - the number to multiply by

Returns:

this*c

cDiv

public static void cDiv(double a,
                        double b,
                        double c,
                        double d,
                        double[] results)

Performs a complex division operation.
The standard complex division performs a set of operations that is suseptible to both overflow and underflow. This method is more numerically stable while still being relatively fast to execute.

Parameters:

a - the real part of the first number

b - the imaginary part of the first number

c - the real part of the second number

d - the imaginary part of the second number

results - an array to store the real and imaginary results in. First index is the real, 2nd is the imaginary.

mutableDivide

public void mutableDivide(double c,
                          double d)

Alters this complex number as if a division by another complex number was performed.

Parameters:

c - the real part of the other number

d - the imaginary part of the other number

mutableDivide

public void mutableDivide(Complex c)

Alters this complex number to contain the result of the division by another

Parameters:

c - the number to divide by

divide

public Complex divide(Complex c)

Creates a new complex number containing the resulting division of this by another

Parameters:

c - the number to divide by

Returns:

this/c

getMagnitude

public double getMagnitude()

Computes the magnitude of this complex number, which is sqrt(Re²+Im²)

Returns:

the magnitude of this complex number

getArg

public double getArg()

Computes the Argument, also called phase, of this complex number. Unless the result is Double.NaN, which occurs only for complex zero, the result will be in the range [-pi, pi]

Returns:

the argument of this complex number

mutateConjugate

public void mutateConjugate()

Alters this complex number so that it represents its complex conjugate instead.

getConjugate

public Complex getConjugate()

Returns a new complex number representing the complex conjugate of this one

Returns:

the complex conjugate of this

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

equals

public boolean equals(java.lang.Object obj)

Overrides:

equals in class java.lang.Object

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object

equals

public boolean equals(java.lang.Object obj,
                      double eps)

Checks if this is approximately equal to another Complex object

Parameters:

obj - the object to compare against

eps - the maximum acceptable difference between values to be considered equal

Returns:

true if the objects are approximately equal