package ac.essex.ooechs.ecj.ecj2java.example.terminals;

import ac.essex.ooechs.ecj.ecj2java.nodes.ParseableGPNode;
import ac.essex.ooechs.ecj.ecj2java.example.data.DoubleData;
import ec.EvolutionState;
import ec.Problem;
import ec.gp.GPData;
import ec.gp.ADFStack;
import ec.gp.GPIndividual;

/**
 *
 * <p>
 * Allows the GP tree to access the variable X, from which it is supposed
 * to calculate Y, in some manner.
 * </p>
 *
 * 
 * <p/>
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version,
 * provided that any use properly credits the author.
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details at http://www.gnu.org
 * </p>
 *
 * @author Olly Oechsle, University of Essex, Date: 05-Sep-2006
 * @version 1.0
 */
public class X extends ParseableGPNode {

    public X() {
        super("x", 0);
    }

    /**
     * Called as the function is evaluated.
     */
    public void eval(final EvolutionState state, final int thread, final GPData input, final ADFStack stack, final GPIndividual individual, final Problem problem) {

        DoubleData rd = ((DoubleData) (input));

        // then add them together
        rd.x = ((ac.essex.ooechs.ecj.ecj2java.example.problems.MathsProblem) problem).x;
    }

    public int getObjectType() {
        return DOUBLE;
    }

    /**
     * Convert this code to pure Java
     */
    public String getJavaCode() {
        return "x";
    }


}