namespace LocationService.Math

{

    using System;

    using System.Collections.Generic;

    using System.Linq;

    using System.Text;

    using System.Threading.Tasks;

    public class NN

    {

        public List<Tuple<string, double[]>> FingerPrintsTable;

        public NN()

        {

            FingerPrintsTable = new List<Tuple<string, double[]>>();

        }

        public void AddFingerPrint(string key,double[] attributes)

        {

            var finger = Tuple.Create(key,attributes);

            AddFingerPrint(finger);

        }

        public void AddFingerPrint(Tuple<string,double[]> fingerprint)

        {

            FingerPrintsTable.Add(fingerprint);

        }

        public void AddFingerPrint(IEnumerable<Tuple<string, double[]>> fingers)

        {

            FingerPrintsTable.AddRange(fingers);

        }

        public void RemoveFingerPrint(string key)

        {

            FingerPrintsTable.RemoveAll(fi => fi.Item1 == key);

        }

        public void RemoveFingerPrint(Tuple<string, double[]> fingerprint)

        {

            FingerPrintsTable.Remove(fingerprint);

        }

        public double EuclideanDistance(double[] x1, double[] x2,int scale=1)

        {

            double sum=0;

            for (int i = 0; i < x1.Length; i++)

            {

                sum += Math.Pow(x1[i] - x2[i], 2);

            }

            sum = Math.Sqrt(sum) / x1.Length*scale;

            return sum;

        }

        public List<Tuple<string, double>> FingerEuclideanList(Tuple<string, double[]> target)

        {

            List<Tuple<string, double>> list = new List<Tuple<string, double>>(); 

            foreach (var finger in FingerPrintsTable)

            {

                list.Add(Tuple.Create(finger.Item1, EuclideanDistance(finger.Item2, target.Item2)));

            }

            return list;

        }

        /// <summary>

        /// Apply the Euclidean distance

        /// </summary>

        /// <param name="target"></param>

        /// <returns></returns>

        public Tuple<string,double> ApplyEuclideanFilter(Tuple<string, double[]> target)

        {

            var list = FingerEuclideanList(target);

            list.Sort((x, y) => (int)((x.Item2 - y.Item2) * 100));

            foreach (var item in list)

            {

                this.log("[Label:{0} Distance:{1}]", item.Item1, item.Item2);

            }

            return list[0];

        }

    }

}

NN nN = new NN();

            nN.AddFingerPrint("爱情",new double[] {3,104});

            nN.AddFingerPrint("爱情", new double[] {2,100 });

            nN.AddFingerPrint("爱情", new double[] {1,81});

            nN.AddFingerPrint("动作", new double[] {101,10 });

            nN.AddFingerPrint("动作", new double[] {99,5});

            nN.AddFingerPrint("动作", new double[] {98,2});

            Tuple<string, double[]> target = Tuple.Create("未知",new double[] {81,80});

            Tuple<string, double> result=null;

            this.MeasureTime(()=> {

                result = nN.ApplyEuclideanFilter(target);

            },time=> {

                this.log("===================================");

                this.log("分类类型:{0}   欧式距离为:{1}", result.Item1, result.Item2);

                this.log("total time:{0}ms", time);

                this.log("===================================");

            });