# LineFunction2D.java

    /* ===========================================================
     * JFreeChart : a free chart library for the Java(tm) platform
     * ===========================================================
     *
     * (C) Copyright 2000-2007, by Object Refinery Limited and Contributors.
     *
     * Project Info:  http://www.jfree.org/jfreechart/index.html
     *
     * This library is free software; you can redistribute it and/or modify it
     * under the terms of the GNU Lesser General Public License as published by
     * the Free Software Foundation; either version 2.1 of the License, or
     * (at your option) any later version.
     *
     * This library 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 Lesser General Public
     * License for more details.
     *
     * You should have received a copy of the GNU Lesser General Public
     * License along with this library; if not, write to the Free Software
     * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
     * USA.
     *
     * [Java is a trademark or registered trademark of Sun Microsystems, Inc.
     * in the United States and other countries.]
     *
     * -------------------
     * LineFunction2D.java
     * -------------------
     * (C) Copyright 2002-2007, by Object Refinery Limited.
     *
     * Original Author:  David Gilbert (for Object Refinery Limited);
     * Contributor(s):   -;
     *
     * Changes:
     * --------
     * 01-Oct-2002 : Version 1 (DG);
     *
     */

    package org.jfree.data.function;

    /**
     * A function in the form y = a + bx.
     */
    public class LineFunction2D implements Function2D {

        /** The intercept. */
        private double a;

        /** The slope of the line. */
        private double b;

        /**
         * Constructs a new line function.
         *
         * @param a  the intercept.
         * @param b  the slope.
         */
        public LineFunction2D(double a, double b) {
            this.a = a;
            this.b = b;
        }

        /**
         * Returns the function value.
         *
         * @param x  the x-value.
         *
         * @return The value.
         */
        public double getValue(double x) {
            return this.a + this.b * x;
        }

    }