org.geolatte.geom

Class Vector

java.lang.Object

org.geolatte.geom.Vector

public class Vector
extends Object

A set of utility functions for basic 2D vector functions.

Author:

Karel Maesen, Geovise BVBA creation-date: 4/7/12

Constructor Summary

Constructors

Constructor and Description
Vector()

Method Summary

Modifier and Type	Method and Description
static <P extends C2D> P	add(P p0, P p1) Adds two Positions.
static <P extends C2D> double	dot(P p0, P p1) Returns the dot-product of the specified Positions
static <P extends C2D> P	perp(P p) Hill's "perp" operator.
static <P extends C2D> double	perpDot(P p0, P p1) Applies the perp dot-operation on the specified Positions
static <P extends C2D> double[]	positionToSegment2D(P p0, P p1, P y) Returns the squared distance and projectionfactor of the position y on the linesegment defined by positions p0 and p1
static <P extends C2D> P	substract(P p0, P p1) Subtracts two Positions.

Methods inherited from class java.lang.Object

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

Constructor Detail

Vector

public Vector()

Method Detail

positionToSegment2D

public static <P extends C2D> double[] positionToSegment2D(P p0,
                                                           P p1,
                                                           P y)

Returns the squared distance and projectionfactor of the position y on the linesegment defined by positions p0 and p1

The projection factor is the value for t that determines the projection of y on the line p0 + t*(p1-p0).

Parameters:

p0 - the start position of the line segment

p1 - the end position of the line segment

y - the position to project onto the linesegment

Returns:

an array of length 2, with first element being the squared distance of Position y to the linesegment, and second element the projection factor

dot

public static <P extends C2D> double dot(P p0,
                                         P p1)

Returns the dot-product of the specified Positions

Parameters:

p0 - first operand

p1 - second operand

Returns:

the dot-product of p0 and p1.

add

public static <P extends C2D> P add(P p0,
                                    P p1)

Adds two Positions.

If any of the parameters are 2D, the operation is performed in 2D.

Parameters:

p0 - first operand

p1 - second operand

Returns:

the sum of p0 and p1.

substract

public static <P extends C2D> P substract(P p0,
                                          P p1)

Subtracts two Positions.

If any of the parameters are 2D, the operation is performed in 2D.

Parameters:

p0 - first operand

p1 - second operand

Returns:

the Position x = p0 - p1.

perp

public static <P extends C2D> P perp(P p)

Hill's "perp" operator.

The application of this operator on a vector P returns the vector perpendicular at 90 deg. counterclockwise from P in the 2D (X/Y) plane.

Parameters:

p - a vector represented by a Position.

Returns:

the vector perpendicular to p in the 2D-plane, at 90 deg. counterclockwise.

perpDot

public static <P extends C2D> double perpDot(P p0,
                                             P p1)

Applies the perp dot-operation on the specified Positions

The perp dot operation on vectors P, Q is defined as dot(perp(P),Q).

This operation will be performed in 2D only.

Parameters:

p0 - first operand

p1 - second operand

Returns:

the Perp dot of p0 and p1.