samer@0: /*
samer@0:  *	Function.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: /**
samer@0:   *		Defines a real-valued function of a single real variable.
samer@0:   *		
samer@0:   */
samer@0: 
samer@0: public abstract class Function
samer@0: {
samer@0: 	public abstract double apply(double in);
samer@0: 
samer@0: 	/** apply function to each element of in, placing result in out */
samer@0: 	public void apply(double [] in, double [] out) {
samer@0: 		for (int i=0; i<in.length; i++) out[i]=apply(in[i]);
samer@0: 	}
samer@0: 
samer@0: 	/** apply function in place, to each element of inout */
samer@0: 	public void apply(double [] inout) {
samer@0: 		for (int i=0; i<inout.length; i++) inout[i]=apply(inout[i]);
samer@0: 	}
samer@0: 
samer@0: 	public void dispose() {}
samer@0: 
samer@0: 	public Function inverse() { throw new Error("no inverse"); }
samer@0: 	public Function derivative() { throw new Error("no derivative"); }
samer@0: 	public abstract String format(String arg);
samer@0: }