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: import  samer.core.*;
samer@0: 
samer@0: public class Constant extends Function implements Generator
samer@0: {
samer@0: 	double k;
samer@0: 
samer@0: 	public Constant() { k=Shell.getInt("constant",1); }
samer@0: 	public Constant(double k) { this.k=k; }
samer@0: 	public void dispose() {}
samer@0: 
samer@0: 	// Generator
samer@0: 	public double next() { return k; }
samer@0: 	public void   next(double [] x) { for (int i=0; i<x.length; i++) x[i]=k; }
samer@0: 
samer@0: 	// Function
samer@0: 	public double apply(double t) { return k; }
samer@0: 	public Function derivative() { return new Zero(); }
samer@0: 
samer@0: 	public String toString() { return "Constant("+k+")"; }
samer@0: 	public String format(String arg) { return X.string(k); }
samer@0: }