samer@0: /*
samer@0:  *	RowColumn.java	
samer@0:  *
samer@0:  *	Copyright (c) 2000, Samer Abdallah, King's College London.
samer@0:  *	All rights reserved.
samer@0:  *
samer@0:  *	This software is provided AS iS and WITHOUT ANY WARRANTY; 
samer@0:  *	without even the implied warranty of MERCHANTABILITY or 
samer@0:  *	FITNESS FOR A PARTICULAR PURPOSE.
samer@0:  */
samer@0: 
samer@0: package samer.maths;
samer@0: 
samer@0: import  samer.core.*;
samer@0: import  samer.core.types.*;
samer@0: import  samer.core.util.*;
samer@0: import  java.util.*;
samer@0: 
samer@0: /**
samer@0: 	Looks like a vector externally, but reads data
samer@0: 	from a row or column of a matrix. Provides 
samer@0: 	commands for setting which row or column to use,
samer@0: 	and for switching between rows and columns.
samer@0:   */
samer@0: 
samer@0: public class RowColumn extends VVector implements Mat, Observer
samer@0: {
samer@0: 	Matrix			M;
samer@0: 	VInteger			num; 
samer@0: 	int				rowcol;
samer@0: 	Mat				mat;
samer@0: 
samer@0: 	public final static Object FLIPPED   = new Object();
samer@0: 	public final static Object SWITCHED  = new Object();
samer@0: 
samer@0: 	public RowColumn(Matrix A) { this( new Node("rowcolumn",A.getNode()), A); }
samer@0: 	public RowColumn(Node n, Matrix A) 
samer@0: 	{ 
samer@0: 		super(n,A.getColumn(0));
samer@0: 
samer@0: 		Shell.push(node);
samer@0: 		M=A; rowcol=COL;
samer@0: 		boolean rowwise=Shell.getBoolean("rowwise",(A.getRowDimension()==1));
samer@0: 		if (rowwise) { vec=A.getRow(0); rowcol=ROW; }
samer@0: 		Shell.pop();
samer@0: 
samer@0: 		if (rowcol==ROW) createVRow();
samer@0: 		else createVColumn();
samer@0: 
samer@0: 		M.addObserver(this);
samer@0: 	}
samer@0: 
samer@0: 	// Vec implementation
samer@0: 	public double[] array() { return null; }
samer@0: 	public Vec getVec() { return this; }
samer@0: 	public Mat mat() { if (mat==null) mat=vec.mat(); return this; }
samer@0: 
samer@0: 	// Mat implementation
samer@0: 	public int width() { return mat.width(); }
samer@0: 	public int height() { return mat.height(); }
samer@0: 	public double get( int i, int j) { return mat.get(i,j); }
samer@0: 	public void set( int i, int j, double t) { mat.set(i,j,t); }
samer@0: 
samer@0: 	private void createVRow()
samer@0: 	{
samer@0: 		Shell.push(getNode().getParent());
samer@0: 		num = new VInteger("row",0,Variable.NOINIT);
samer@0: 		num.setRange(0,M.getRowDimension()-1);
samer@0: 		num.addObserver(this);
samer@0: 		Shell.registerViewable(num);
samer@0: 		Shell.pop();
samer@0: 	}
samer@0: 
samer@0: 	private void createVColumn()
samer@0: 	{
samer@0: 		Shell.push(getNode().getParent());
samer@0: 		num = new VInteger("column",0,Variable.NOINIT);
samer@0: 		num.setRange(0,M.getColumnDimension()-1);
samer@0: 		num.addObserver(this);
samer@0: 		Shell.registerViewable(num);
samer@0: 		Shell.pop();
samer@0: 	}
samer@0: 
samer@0: 	public void dispose() 
samer@0: 	{
samer@0: 		Shell.deregisterViewable(num);
samer@0: 		M.deleteObserver(this);
samer@0: 		num.dispose();
samer@0: 		super.dispose();
samer@0: 	}
samer@0: 
samer@0: 	public void setNum(int n) { num.value=n; num.changed(); }
samer@0: 
samer@0: 	public void setRow(int r) { 
samer@0: 		num.value=r; vec=M.getRow(r);
samer@0: 		if (mat!=null) mat=vec.mat();
samer@0: 		if (rowcol==ROW) changed(SWITCHED);
samer@0: 		else { rowcol=ROW; changed(FLIPPED); }
samer@0: 	}
samer@0: 
samer@0: 	public void setColumn(int r) { 
samer@0: 		num.value=r; vec=M.getColumn(r); 
samer@0: 		if (mat!=null) mat=vec.mat();
samer@0: 		if (rowcol==COL) changed(SWITCHED);
samer@0: 		else { rowcol=COL; changed(FLIPPED); }
samer@0: 	}
samer@0: 
samer@0: 	public void getCommands(Agent.Registry r) {
samer@0: 		super.getCommands(r); r.group();
samer@0: 		r.add("row").add("column").add("dispose");
samer@0: 	}
samer@0: 
samer@0: 	public void execute(String cmd, Environment env) throws Exception
samer@0: 	{
samer@0: 		if (cmd.equals("row")) {
samer@0: 
samer@0: 			if (rowcol==COL) {
samer@0: 				num.deleteObserver(this);
samer@0: 				num.dispose();
samer@0: 				createVRow();
samer@0: 				setRow(0);
samer@0: 			}
samer@0: 
samer@0: 			// no need to get number: num is automatically exposed
samer@0: 			// env.datum().get(num);
samer@0: 
samer@0: 		} else if (cmd.equals("column")) {
samer@0: 
samer@0: 			if (rowcol==ROW) {
samer@0: 				num.deleteObserver(this);
samer@0: 				num.dispose();
samer@0: 				createVColumn();
samer@0: 				setColumn(0);
samer@0: 			}
samer@0: 
samer@0: 			// no need to get number: num is automatically exposed
samer@0: 			// env.datum().get(num);
samer@0: 		} else if (cmd.equals("dispose")) {
samer@0: 			dispose();
samer@0: 		} else super.execute(cmd,env);
samer@0: 	}
samer@0: 
samer@0: 	public void notifyObservers(Object s) {
samer@0: 		super.notifyObservers(s);
samer@0: 		if (s!=Viewable.DISPOSING && s!=RowColumn.SWITCHED) {
samer@0: 			M.changed(this); // pass notification onto matrix observers
samer@0: 		}
samer@0: 	}
samer@0: 
samer@0: 	public void update(Observable o, Object s) { // &&&
samer@0: 		if (M.equals(o)) { // Matrix changed
samer@0: 			if (s==Viewable.DISPOSING)	dispose();
samer@0: 			else if (s!=this)	super.notifyObservers(this);
samer@0: 		} else if (num.equals(o)) {
samer@0: 			if (rowcol==ROW) setRow(num.value);
samer@0: 			else setColumn(num.value);
samer@0: 		}
samer@0: 	}
samer@0: 
samer@0: 	private final static int ROW = 1;
samer@0: 	private final static int COL = 2;
samer@0: }