/*
* Licensed to the Apache Software Foundation (ASF) Under one or more
* contributor license agreements.  See the NOTICE file distributed with
* this work for Additional information regarding copyright ownership.
* The ASF licenses this file to You Under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License.  You may obtain a copy of the License at
*
*     http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed Under the License is distributed on an "AS Is" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations Under the License.
*/

namespace HH.WMS.Utils.NPOI.SS.Formula.Functions
{

    /*
     * Implementation of Excel function SUMXMY2()<p/>
     * 
     * Calculates the sum of squares of differences between two arrays of the same size.<br/>
     * <b>Syntax</b>:<br/>
     * <b>SUMXMY2</b>(<b>arrayX</b>, <b>arrayY</b>)<p/>
     * 
     * result = &Sigma;<sub>i: 0..n</sub>(x<sub>i</sub>-y<sub>i</sub>)<sup>2</sup>
     * 
     * @author Amol S. Deshmukh &lt; amolweb at ya hoo dot com &gt; 
     */
    public class Sumxmy2 : XYNumericFunction
    {

        public class Accumulator1:Accumulator
        {
            public double Accumulate(double x, double y)
            {
                double xmy = x - y;
                return xmy * xmy;
            }
        }

        private static Accumulator XMinusYSquaredAccumulator = new Accumulator1();
        public override Accumulator CreateAccumulator()
        {
            return XMinusYSquaredAccumulator;
        }
    }

}