databionics.esom.neighborhood
Class CachedNeighborhood

java.lang.Object
  databionics.esom.neighborhood.Neighborhood
      databionics.esom.neighborhood.CachedNeighborhood

Direct Known Subclasses:

ConeNeighborhood, EpanechicovNeighborhood, GaussNeighborhood, MexicanHatNeighborhood

public abstract class CachedNeighborhood
extends Neighborhood

Abstract base class for neighborhood kernels with a cache of precalculated values. Subclasses have to override the calculate(int distance) method and might want to override the init() method. Make sure to call super.init() as the last command in init() to initialize the cache.

Field Summary

protected static org.apache.log4j.Logger	log interface to log4j system
protected cern.colt.matrix.DoubleMatrix1D	weights cache with precalculated values of the weights

Fields inherited from class databionics.esom.neighborhood.Neighborhood

radius, scaling

Constructor Summary

CachedNeighborhood()
Create a new neighborhood object

CachedNeighborhood(int radius, double scaling)
Create a new neighborhood object

Method Summary

double	get(int distance) Get weight for distance from kernel center
void	init() Initialize the neighborhood.

Methods inherited from class databionics.esom.neighborhood.Neighborhood

calculate, setRadius, setScaling

Methods inherited from class java.lang.Object

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

Field Detail

log

protected static final org.apache.log4j.Logger log

interface to log4j system

weights

protected cern.colt.matrix.DoubleMatrix1D weights

cache with precalculated values of the weights

Constructor Detail

CachedNeighborhood

public CachedNeighborhood()

Create a new neighborhood object

CachedNeighborhood

public CachedNeighborhood(int radius,
                          double scaling)

Create a new neighborhood object

Parameters:

radius - radius of kernel

scaling - scaling factor for all weights

Method Detail

init

public void init()

Initialize the neighborhood. Call this after setting radius and scaling

Specified by:

init in class Neighborhood

get

public double get(int distance)

Get weight for distance from kernel center

Overrides:

get in class Neighborhood

Parameters:

distance - distance on grid from center

Returns:

weight for this distance