Jampack

Class Z

java.lang.Object

Jampack.Z

public class Z
extends Object

Z is a mutable complex variable class. It is designed to perform complex arithmetic without creating a new Z at each operation. Specifically, binary operations have the form c.op(a,b), in which a, b, and c need not be different. The method places the complex number a.op.b in c. The method also returns a pointer to c. Thus the class supports two styles of programming. For example to compute e = a*b + c*d you can write

z1.Times(a,b)
z2.Times(c,d)
e.Plus(z1,z2)

or

e.Plus(z1.Times(a,b), z2.Times(a,b))

Since objects of class Z are mutable, the use of the assignment operator "=" with these objects is deprecated. Use Eq.

The functions are reasonably resistent to overflow and underflow. But the more complicated ones could almost certainly be improved.

Version:

Pre-alpha

Author:

G. W. Stewart

Field Summary

Fields

Modifier and Type	Field and Description
static Z	I Imaginary unit.
double	im The imaginary part of Z.
static Z	ONE Complex 1.
double	re The real part of Z.
static Z	ZERO Complex 0.

Constructor Summary

Constructors

Constructor and Description
Z() Creates a Z and initializes it to zero.
Z(double x) Creates a Z and initializes its real part.
Z(double x, double y) Creates a Z and initializes its real and imaginary parts.
Z(Z a) Creates a Z and initializes it to another Z.

Method Summary

Methods

Modifier and Type	Method and Description
static double	abs(Z z) Computes the absolute value of a Z.
static double	abs1(Z z) Computes the 1-norm of a Z
Z	Conj(Z a) Computes the conjugate of a Z.
Z	Div(Z a, double b) Computes the quotient of a Z and a double.
Z	Div(Z a, Z b) Computes the quotient of two Z's.
Z	Eq(double a, double b) Resets the real and imaginary parts of a Z.
Z	Eq(Z a) Resets the real and imaginary parts of a Z to those of another Z.
Z	Exch(Z a) Interchanges the real and imaginary parts of two Z's.
boolean	IsEqual(Z z1, Z z2) Tests two Z'z for equality.
Z	Minus(Z a) Computes unary minus of a Z.
Z	Minus(Z a, Z b) Computes the difference of two Z's.
Z	Plus(Z a, Z b) Computes the sum of two Z's.
Z	Sqrt(Z a) Computes the principal value of the square root of a Z.
Z	Times(double a, Z b) Computes the product of a double and a Z.
Z	Times(Z a, Z b) Computes the product of two Z's.

Methods inherited from class java.lang.Object

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

Field Detail

ONE

public static final Z ONE

Complex 1.

ZERO

public static final Z ZERO

Complex 0.

I

public static final Z I

Imaginary unit.

re

public double re

The real part of Z.

im

public double im

The imaginary part of Z.

Constructor Detail

Z

public Z()

Creates a Z and initializes it to zero.

Z

public Z(double x,
 double y)

Creates a Z and initializes its real and imaginary parts.

Parameters:

x - a double

y - a double

Z

public Z(double x)

Creates a Z and initializes its real part.

Parameters:

x - a double

Z

public Z(Z a)

Creates a Z and initializes it to another Z.

Parameters:

a - a Z

Method Detail

IsEqual

public boolean IsEqual(Z z1,
              Z z2)

Tests two Z'z for equality.

Parameters:

z1 - a Z

z2 - a Z

Returns:

true if z1=z2, otherwise false

Eq

public Z Eq(Z a)

Resets the real and imaginary parts of a Z to those of another Z.

Parameters:

a - a Z

Returns:

this = a;

Eq

public Z Eq(double a,
   double b)

Resets the real and imaginary parts of a Z.

Parameters:

a - a double

b - a double

Returns:

this = a + ib

Exch

public Z Exch(Z a)

Interchanges the real and imaginary parts of two Z's.

Parameters:

a - a Z

Returns:

this = a, with a set to the original value of this.

abs1

public static double abs1(Z z)

Computes the 1-norm of a Z

abs

public static double abs(Z z)

Computes the absolute value of a Z.

Parameters:

z - a Z

Returns:

the absolute vaue of Z

Conj

public Z Conj(Z a)

Computes the conjugate of a Z.

Parameters:

a - a Z

Returns:

this = conj(a);

Minus

public Z Minus(Z a)

Computes unary minus of a Z.

Parameters:

a - a Z

Returns:

this = -a;

Plus

public Z Plus(Z a,
     Z b)

Computes the sum of two Z's.

Parameters:

a - a Z

b - a Z

Returns:

this = a + b

Minus

public Z Minus(Z a,
      Z b)

Computes the difference of two Z's.

Parameters:

a - a Z

b - a Z

Returns:

this = a - b

Times

public Z Times(Z a,
      Z b)

Computes the product of two Z's.

Parameters:

a - a Z

b - a Z

Returns:

this = ab

Times

public Z Times(double a,
      Z b)

Computes the product of a double and a Z.

Parameters:

a - a double

b - a Z

Returns:

this = ab

Div

public Z Div(Z a,
    Z b)
      throws JampackException

Computes the quotient of two Z's. Throws a JampackException if the denominator is zero.

Parameters:

a - a Z

b - a Z

Returns:

this = a/b

Throws:

JampackException - Thrown if b is zero.

Div

public Z Div(Z a,
    double b)
      throws JampackException

Computes the quotient of a Z and a double. Throws a JampackException if the denominator is zero.

Parameters:

a - a Z

b - a double

Returns:

this = a/b

Throws:

JampackException - Thrown if b is zero.

Sqrt

public Z Sqrt(Z a)

Computes the principal value of the square root of a Z.

Parameters:

a - a Z

this - = sqrt(a)