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: /* Similar to binary, but has different bit probabilities
samer@0:    for elements of vector
samer@0:  */
samer@0: 
samer@0: package samer.maths.random;
samer@0: import  samer.maths.*;
samer@0: import  samer.core.types.*;
samer@0: 
samer@0: public class BinaryVec extends BaseRandom
samer@0: {
samer@0: 	int		n;
samer@0: 	VVector	probs;
samer@0: 	double	[] p;
samer@0: 	boolean ownp;
samer@0: 
samer@0: 	public BinaryVec(int n, double pp) { 
samer@0: 		this(new VVector("probs",n)); 
samer@0: 		ownp=true;
samer@0: 		for (int i=0; i<n; i++) p[i]=pp;
samer@0: 	}
samer@0: 
samer@0: 	public BinaryVec(VVector probs) { 
samer@0: 		this.n=probs.size();
samer@0: 		this.probs=probs;
samer@0: 		p=probs.array(); 
samer@0: 		ownp=false;
samer@0: 	}
samer@0: 
samer@0: 	public int  getSize() { return n; }
samer@0: 	public void dispose() { if (ownp) probs.dispose(); }
samer@0: 	public double next() { return (rnd.nextDouble()<p[0]) ? 1.0 : 0.0; }
samer@0: 	public void   next(double [] x) { 
samer@0: 		int i, j;
samer@0: 		for (i=0,j=0; i<x.length; i++,j++) {
samer@0: 			if (j>=n) j=0;
samer@0: 			x[i]=(rnd.nextDouble()<p[j]) ? 1.0 : 0.0; 
samer@0: 		}
samer@0: 	}
samer@0: }