private void button7_Click(object sender, EventArgs e)
        {
            ClearForm();
            PreparareForm(-11, 11, -11, 11);
            Random r = new Random();

            int n = r.Next(3, 20);
            int m = r.Next(3, n);
            XMid = chart1.Series.Add("Points");
            XMid.ChartType = SeriesChartType.Point;
            List<int> xx = new List<int>();
            List<int> yy = new List<int>();
            for (int i = 0; i < n; i++)
            {
                int x = r.Next(-10, 10);
                int y = r.Next(-10, 10);
                richTextBox1.AppendText("x: " + x + " y: " + y + "\n");
                XMid.Points.AddXY(x, y);
                xx.Add(x);
                yy.Add(y);
            }

            X1X2 = chart1.Series.Add("Other Points");
            X1X2.ChartType = SeriesChartType.Point;
            int count = 0;
            for (int i = 0; i < m; i++)
            {
                double ave = vidutinis(xx, yy);
                other_points(X1X2, ave, xx, yy, count);
                count++;
            }


            //richTextBox1.AppendText("\n" + ave);



        }

        private void other_points(Series xx, double ave, List<int> x, List<int> y, int count)
        {
            if (count < 10)
                xx.Points.AddXY(x[count] + ave, y[count] - ave*2);
            if (count > 10)
                xx.Points.AddXY(x[count] - ave, y[count] + ave);
        }

        private double vidutinis(List<int> x, List<int> y)
        {
            double a = 0;
            for (int i = 0; i < x.Count; i++)
            {
                for (int k = 0; k < y.Count; k++)
                {
                    if (i != k)
                        a += Math.Pow((Math.Pow((x[k] - x[i]), 2) + Math.Pow((y[k] - y[i]), 2)), 1 / 2);
                }
            }
            double ave = a / (x.Count * y.Count);
            return ave;
        }