新聞 : 東大生藍芽耳機掉一隻「靠數學找回」！日網驚呆：根本GPS

using System;

using System.Diagnostics;

using System.Globalization;

using static System.Windows.Forms.VisualStyles.VisualStyleElement.Window;

using System.Windows.Forms;

using System.IO;

namespace WinFormsApp1

{

    public partial class Form1 : Form

    {

        int pointCounts;

        int[] pointPositions = new int[3];

        public Form1()

        {

            InitializeComponent();

        }

        private void button1_Click(object sender, EventArgs e)

        {

            calculate();

        }

        private void calculate()

        {

            string str;

            char ch = ';';

            char dot = ',';

            str = textBox1.Text;

            string[] sArray = str.Split(new char[2] { ';', ',' });

            int chfreq = str.Count(f => (f == ch));

            int dotfreq = str.Count(f => (f == dot));

            float[,] coordinations = new float[90, 3];

            

           for (int i = 0; i < sArray.Count(); i++)

            {

                Trace.WriteLine(sArray[i]);

            }                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    

                                                                                                                                                        

            if (sArray.Count() % 3 == 0 && textBox2.Text != null)

            {

                pointCounts = sArray.Count() / 3;

                for (int i = 0; i < (sArray.Count() + 1) / 3; i++)

                {

                    for (int j = 0; j <= 2; j++)

                    {

                        coordinations[i, j] = float.Parse(sArray[i * 3 + j], CultureInfo.InvariantCulture.NumberFormat);

                        //Trace.WriteLine("arrary count " + sArray.Count() + "array number : "  + coordinations[i,j] + " i value : " + i + " j value : " + j);

                    }

                }

                radious(coordinations);

            }

            else

            {

                var result = MessageBox.Show("error", "error",

                             MessageBoxButtons.YesNo,

                             MessageBoxIcon.Question);

            }

            //label1.Text = chfreq.ToString() + "    " + dotfreq.ToString();

        }

        private void radious(float[,] inputArray)

        {

            double radiusGap = 100f;

            float[] currentCircleCenter = new float[3];

            double currentRadius;

            float targetRadius = float.Parse(textBox2.Text);

            double bestRadius = 0;

            string textString = "";

            foreach (float a in inputArray)

            {

                if (a != null) { }

                //Trace.WriteLine(inputArray.Length);

            }

            for (int i = 0; i <= pointCounts - 2 - 1; i++)

            {

                for (int j = i + 1; j <= pointCounts - 1 - 1; j++)

                {

                    for (int k = j + 1; k <= pointCounts - 1; k++)

                    {

                        float a1, a2, a3, b1, b2, b3, c1, c2, c3, d1, d2, d3, factor0, factor1, factor2, factor3;

                        a1 = inputArray[i, 0] - inputArray[j, 0]; a2 = inputArray[i, 1] - inputArray[j, 1]; a3 = inputArray[i, 2] - inputArray[j, 2];

                        b1 = inputArray[j, 0] - inputArray[k, 0]; b2 = inputArray[j, 1] - inputArray[k, 1]; b3 = inputArray[j, 2] - inputArray[k, 2];

                        c1 = (inputArray[j, 1] - inputArray[i, 1]) * (inputArray[k, 2] - inputArray[i, 2]) - (inputArray[j, 2] - inputArray[i, 2]) * (inputArray[k, 1] - inputArray[i, 1]);

                        c2 = (inputArray[j, 2] - inputArray[i, 2]) * (inputArray[k, 0] - inputArray[i, 0]) - (inputArray[j, 0] - inputArray[i, 0]) * (inputArray[k, 2] - inputArray[i, 2]);

                        c3 = (inputArray[j, 0] - inputArray[i, 0]) * (inputArray[k, 1] - inputArray[i, 1]) - (inputArray[j, 1] - inputArray[i, 1]) * (inputArray[k, 0] - inputArray[i, 0]);

                        d1 = (inputArray[i, 0] * inputArray[i, 0] - inputArray[j, 0] * inputArray[j, 0] + inputArray[i, 1] * inputArray[i, 1] - inputArray[j, 1] * inputArray[j, 1] + inputArray[i, 2] * inputArray[i, 2] - inputArray[j, 2] * inputArray[j, 2]) / 2;

                        d2 = (inputArray[j, 0] * inputArray[j, 0] - inputArray[k, 0] * inputArray[k, 0] + inputArray[j, 1] * inputArray[j, 1] - inputArray[k, 1] * inputArray[k, 1] + inputArray[j, 2] * inputArray[j, 2] - inputArray[k, 2] * inputArray[k, 2]) / 2;

                        d3 = c1 * inputArray[i, 0] + c2 * inputArray[i, 1] + c3 * inputArray[i, 2];

                        factor0 = a1 * b2 * c3 + b1 * c2 * a3 + c1 * a2 * b3 - c1 * b2 * a3 - b1 * a2 * c3 - a1 * c2 * b3;

                        factor1 = d1 * b2 * c3 + d2 * c2 * a3 + d3 * a2 * b3 - d3 * b2 * a3 - d2 * a2 * c3 - d1 * c2 * b3;

                        factor2 = a1 * d2 * c3 + b1 * d3 * a3 + c1 * d1 * b3 - c1 * d2 * a3 - b1 * d1 * c3 - a1 * d3 * b3;

                        factor3 = a1 * b2 * d3 + b1 * c2 * d1 + c1 * a2 * d2 - c1 * b2 * d1 - b1 * a2 * d3 - a1 * c2 * d2;

                        currentCircleCenter[0] = factor1 / factor0; currentCircleCenter[1] = factor2 / factor0; currentCircleCenter[2] = factor3 / factor0;

                        currentRadius = Math.Pow(Math.Pow(inputArray[i, 0] - currentCircleCenter[0], 2) + Math.Pow(inputArray[i, 1] - currentCircleCenter[1], 2) + Math.Pow(inputArray[i, 2] - currentCircleCenter[2], 2), 0.5);

                        textString = textString + " _points : " + (i + 1).ToString() + " , " + (j + 1).ToString() + " , " + (k + 1).ToString() +

                                       " _radius : " + currentRadius.ToString() + " rnrn ";

                        if (Math.Abs(currentRadius - targetRadius) < radiusGap)

                        {

                            radiusGap = Math.Abs(currentRadius - targetRadius);

                            bestRadius = currentRadius;

                            pointPositions[0] = i + 1; pointPositions[1] = j + 1; pointPositions[2] = k + 1;

                            Trace.WriteLine("radius : " + currentRadius + " points positions : " + i.ToString() + j.ToString() + k.ToString());

                        }

                        textBox3.Text = "radius : " + bestRadius + " , best points : " + pointPositions[0].ToString() + " , " + pointPositions[1].ToString() + " , " + pointPositions[2].ToString() + "   rn rn    " + textString;

                    }

                }

            }

        }

        private void textBox2_TextChanged(object sender, EventArgs e)

        {

        }

        //Console.WriteLine(item);

    }

}