jrobots.utils
Class Vector

java.lang.Object
  jrobots.utils.Vector

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable

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

This class represents a two dimensional vector.

The internal fields are immutable - they are set once at the construction of the vector. All methods returning a vector construct a new vector.

The vector can be treated both in Cartesian and in polar form. Like below:

• (X=1;Y=0) = (angle=0°;length=1)
• (X=0;Y=1) = (angle=90°;length=1)
• (X=-1;Y=0) = (angle=180°;length=1)
• (X=0;Y=-1) = (angle=270°;length=1)

See Also:

getAngle(), getLength(), add(Vector), sub(Vector), mult(double), getX(), getY(), ZERO, rotate(Angle), projection(Angle), vectorProduct(Vector), Serialized Form

ZERO

public static final Vector ZERO

Vector

public Vector()

Constructs the zero vector.

Vector

public Vector(Angle angle,
              double length)

Constructs a vector by polar coordinates.

Parameters:

angle -

length -

Vector

public Vector(double length,
              Angle angle)

Constructs a vector by polar coordinates.

Parameters:

length -

angle -

Vector

public Vector(double x,
              double y)

Constructs a vector by Cartesian coordinates (x,y).

Parameters:

x - double

y - double

add

public Vector add(Vector v)

Addition of two vectors. Result is a new vector.

Parameters:

v - Summand

Returns:

sum as new vector

clone

public Vector clone()

Overrides:

clone in class java.lang.Object

distanceTo

public double distanceTo(Vector b)

Calculates the distance between two vectors.

Note that the vectors must share the same reference system.

Parameters:

b - Vector

Returns:

|this-b|

equals

public boolean equals(java.lang.Object obj)

Overrides:

equals in class java.lang.Object

getAngle

public Angle getAngle()

Gets the polar angle of this vector. Zero vectors point east.

Returns:

Angle

getLength

public double getLength()

Returns the length of this vector

Returns:

length

getNegative

public Vector getNegative()

The inverse vector has same length and opposite direction.

Returns:

new inverse vector

getNormal

public Vector getNormal()

Scales this vector to a length of 1. Zero vectors point east.

Returns:

new normalized vector

getX

public double getX()

Returns the Cartesian x component.

Returns:

double

getY

public double getY()

Returns the Cartesian y component.

Returns:

double

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object

mult

public Vector mult(double factor)

Scales this vector by a given factor.

Parameters:

factor -

Returns:

product as new vector

projection

public double projection(Angle angle)

Projects the vector onto a given Angle. The result is the projected length.

Parameters:

angle - - projection angle

Returns:

length of vector in the given direction

rotate

public Vector rotate(Angle angle)

Rotates a vector in clockwise direction. The result is a new vector. Length remains and direction is rotated by the given angle.

Parameters:

angle - rotation angle (>0 for clockwise rotation)

Returns:

new rotated vector.

sub

public Vector sub(Vector v)

Subtracts a given vector from this vector. Result is a new vector.

Parameters:

v - Subtrahend

Returns:

difference as new vector

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

vectorProduct

public double vectorProduct(Vector b)

The vector product in the two dimensional space results in a scalar value. The mathematical representation of a.vectorProduct(b) is a x b.

Parameters:

b - - second parameter of the vector product

Returns:

scalar value