appletbots.geometry
Class Vector

java.lang.Object
  appletbots.geometry.Vector

All Implemented Interfaces:

java.lang.Comparable

public class Vector
extends java.lang.Object
implements java.lang.Comparable

This class represents an immutable two-dimensional vector

Author:

Erik Rasmussen

Field Summary

double	x The x-component of the vector
static Vector	X_AXIS A normalized vector in the direction of the x-axis
double	y The y-component of the vector
static Vector	Y_AXIS A normalized vector in the direction of the y-axis
static Vector	ZERO A zero vector

Constructor Summary

Vector(double x, double y)
Creates a new vector with the given x and y components

Vector(Point start, Point end)
Constructs a new vector from one point to another

Method Summary

Vector	add(Vector v) Returns the result of adding this vector to another vector
static Vector	average(java.util.Collection vectors) Returns the average of a collection of vectors
java.lang.Object	clone() Returns a copy of this vector
int	compareTo(java.lang.Object o) Compares this vector to another based solely on magnitude.
Vector	divide(double divisor) Returns the result of dividinig this vector by a scalar number
double	dotProduct(Vector v) Returns the dot product of this vector and another vector
boolean	equals(java.lang.Object obj) Returns whether or not this vector equals another vector
double	getAngleToVector(Vector v) Returns the angle (in radians) from this vector to the given vector
double	getLength() Returns the length of the vector
static Vector	getRandom(double length) Returns a random vector of the given length
boolean	isAligned(Vector v) Returns whether or not this vector is aligned (pointing in same direction) to the given vector
boolean	isParallel(Vector v) Returns whether or not this vector is parellel to the given vector
Vector	multiply(double multiplicand) Returns the result of multiplying this vector times a scalar number
Vector	normalize() Creates a new vector aligned with this one with a length of 1
Vector	rotate(double theta) Returns the result of rotating this vector by theta radians
Vector	setLength(double length) Creates a new vector aligned with this one with the given length
Vector	subtract(Vector v) Returns the result of subtracting another vector from this vector
java.lang.String	toString() Returns a string representation of this vector

Methods inherited from class java.lang.Object

finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

x

public double x

The x-component of the vector

y

public double y

The y-component of the vector

ZERO

public static Vector ZERO

A zero vector

X_AXIS

public static Vector X_AXIS

A normalized vector in the direction of the x-axis

Y_AXIS

public static Vector Y_AXIS

A normalized vector in the direction of the y-axis

Constructor Detail

Vector

public Vector(double x,
              double y)

Creates a new vector with the given x and y components

Parameters:

x - The x-component of the vector

y - The y-component of the vector

Vector

public Vector(Point start,
              Point end)

Constructs a new vector from one point to another

Parameters:

start - The start point

end - The end point

Method Detail

getRandom

public static Vector getRandom(double length)

Returns a random vector of the given length

Parameters:

length - The length of the vector

Returns:

A random vector of the given length

average

public static Vector average(java.util.Collection vectors)

Returns the average of a collection of vectors

Parameters:

vectors - A collection of vectors

Returns:

The average of the collection of vectors

getLength

public double getLength()

Returns the length of the vector

Returns:

The length of the vector

setLength

public Vector setLength(double length)

Creates a new vector aligned with this one with the given length

Parameters:

length - The length of the new vector

Returns:

A new vector aligned with this one with the given length

normalize

public Vector normalize()

Creates a new vector aligned with this one with a length of 1

Returns:

A new vector aligned with this one with a length of 1

multiply

public Vector multiply(double multiplicand)

Returns the result of multiplying this vector times a scalar number

Parameters:

multiplicand - The scalar number to multiply the vector by

Returns:

The result of multiplying this vector times a scalar number

divide

public Vector divide(double divisor)

Returns the result of dividinig this vector by a scalar number

Parameters:

divisor - The scalar number to divide the vector by

Returns:

The result of dividing this vector by a scalar number

add

public Vector add(Vector v)

Returns the result of adding this vector to another vector

Parameters:

v - Another vector

Returns:

The result of adding this vector to another vector

subtract

public Vector subtract(Vector v)

Returns the result of subtracting another vector from this vector

Parameters:

v - Another vector

Returns:

The result of subtracting another vector from this vector

dotProduct

public double dotProduct(Vector v)

Returns the dot product of this vector and another vector

Parameters:

v - Another vector

Returns:

The dot product of this vector and another vector

rotate

public Vector rotate(double theta)

Returns the result of rotating this vector by theta radians

Parameters:

theta - The number of radians to rotate the vector

Returns:

The result of rotating this vector by theta radians

getAngleToVector

public double getAngleToVector(Vector v)

Returns the angle (in radians) from this vector to the given vector

Parameters:

v - Another vector

Returns:

The angle (in radians) from this vector to the given vector

isParallel

public boolean isParallel(Vector v)

Returns whether or not this vector is parellel to the given vector

Parameters:

v - Another vector

Returns:

Whether or not this vector is parellel to the given vector

isAligned

public boolean isAligned(Vector v)

Returns whether or not this vector is aligned (pointing in same direction) to the given vector

Parameters:

v - Another vector

Returns:

Whether or not this vector is aligned (pointing in same direction) to the given vector

equals

public boolean equals(java.lang.Object obj)

Returns whether or not this vector equals another vector

Overrides:

equals in class java.lang.Object

Parameters:

obj - Another vector

Returns:

Whether or not this vector equals another vector

clone

public java.lang.Object clone()

Returns a copy of this vector

Overrides:

clone in class java.lang.Object

Returns:

A copy of this vector

toString

public java.lang.String toString()

Returns a string representation of this vector

Overrides:

toString in class java.lang.Object

Returns:

A string representation of this vector

compareTo

public int compareTo(java.lang.Object o)

Compares this vector to another based solely on magnitude.

Specified by:

compareTo in interface java.lang.Comparable

Parameters:

o - the Object to be compared.

Returns:

a negative integer, zero, or a positive integer as this object is less than, equal to, or greater than the specified object.

Throws:

java.lang.ClassCastException - if the specified object's type prevents it from being compared to this Object.