samer@0: package samer.mds;
samer@0: 
samer@0: import samer.maths.*;
samer@0: import samer.tools.*;
samer@0: import samer.core.types.*;
samer@0: import java.util.*;
samer@0: 
samer@0: /** Compute component-wise filter coefficients using a
samer@0: 	a distance/proximity matrix. The filter kernel is centred on
samer@0: 	one of the elements, so that the coefficients are a function
samer@0: 	of the distance/proximity between each unit and the given
samer@0: 	"pivot" element.
samer@0: */
samer@0: 	 
samer@0: public class ProximityFilter extends NullTask implements Observer {
samer@0: 	Matrix		R;
samer@0: 	VVector		F;
samer@0: 	VFunction	map;		// map from proximity to coeff.
samer@0: 	VInteger	i;			// centre element, num elements
samer@0: 
samer@0: 	public ProximityFilter(Matrix R, VVector F, VFunction map) {
samer@0: 		this.R=R; this.F=F; this.map=map;
samer@0: 		i=new VInteger("pivot",0);
samer@0: 		i.setRange(0,R.getRowDimension()-1);
samer@0: 
samer@0: 		R.addObserver(this);
samer@0: 		map.addObserver(this);
samer@0: 		i.addObserver(this);
samer@0: 	}
samer@0: 	public void run() { 	map.getFunction().apply(R.getArray()[i.value],F.array()); }
samer@0: 	public void update(Observable obs, Object arg) { run(); F.changed(); }
samer@0: 	public void dispose() {
samer@0: 		map.deleteObserver(this);
samer@0: 		R.deleteObserver(this);
samer@0: 		i.dispose();
samer@0: 	}
samer@0: }