de.aitools.aq.algebra.vector.functions
Class DotProduct

java.lang.Object
  de.aitools.aq.algebra.vector.functions.DotProduct

All Implemented Interfaces:

Proximity<Vector>

public final class DotProduct
extends java.lang.Object
implements Proximity<Vector>

The Dot Product of two vectors is defined as the sum of the pairwise products of the coordinate values of the vectors.
This is not a real proximity measure. A higher value of a dot product does not necessarily signal more proximate vectors. However, if vectors are prepared specially, the dot product can be used as a measure of relevance. That is why there is no computeNormalizedProximity(Vector, Vector) implemented: The normalization depends on the special case. So only use this if you know what you are doing.

Version:

$Id: DotProduct.java,v 1.1 2011/06/22 14:22:49 dogu3912 Exp $

Author:

johannes.kiesel(/\t)uni-weimar.de

Constructor Summary

DotProduct()
Construct a new DotProduct.

Method Summary

double	computeNormalizedProximity(Vector v1, Vector v2) Compute a kind of proximity between two objects. The value returned by this method has to be between 0 (meaning they are as far away (according to the proximity measure) from each other as possible) and 1 (identical objects according to the proximity measure).
double	computeProximity(Vector v1, Vector v2) Compute a kind of proximity between two objects.

Methods inherited from class java.lang.Object

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

Constructor Detail

DotProduct

public DotProduct()

Construct a new DotProduct.

Method Detail

computeProximity

public double computeProximity(Vector v1,
                               Vector v2)

Description copied from interface: Proximity

Compute a kind of proximity between two objects. A higher value signals higher proximity.

Specified by:

computeProximity in interface Proximity<Vector>

Parameters:

v1 - One object, to be compared to the...

v2 - ...second object

Returns:

Computed proximity

computeNormalizedProximity

public double computeNormalizedProximity(Vector v1,
                                         Vector v2)

Description copied from interface: Proximity

Compute a kind of proximity between two objects.
The value returned by this method has to be between 0 (meaning they are as far away (according to the proximity measure) from each other as possible) and 1 (identical objects according to the proximity measure).

Specified by:

computeNormalizedProximity in interface Proximity<Vector>

Parameters:

v1 - One object, to be compared to the...

v2 - ...second object

Returns:

Computed normalized proximity