private void FillTextBox()
{
textBox1.Clear();
textBox1.Text += $"P_1(x) = {LinearRegression.BeautifyPolynomial(1)}";
textBox1.Text += Environment.NewLine;
textBox1.Text += $"P_2(x) = {LinearRegression.BeautifyPolynomial(2)}";
textBox1.Text += Environment.NewLine;
var prec = LinearRegression.GetPrecisePolynomial(1);
textBox1.Text += $"P_{prec}(x) = {LinearRegression.BeautifyPolynomial(prec)}";
}
private void CreateChart()
{
double[] x = points.Select(_ => _.Item1).ToArray();
double[] y = points.Select(_ => _.Item2).ToArray();
double Xmin = x.Min();
double Xmax = x.Max();
double Ymin = y.Min();
double Ymax = y.Max();
double step_x = (Xmax - Xmin) / x.Length;
double step_y = (Ymax - Ymin) / y.Length;
double[] y_1 = LinearRegression.CalculateY(1);
double[] y_2 = LinearRegression.CalculateY(2);
double[] y_p = LinearRegression.CalculateY(LinearRegression.GetPrecisePolynomial(1));
chart1.Series.Clear();
chart1.ChartAreas.Clear();
chart1.Legends.Clear();
ChartArea area = new ChartArea();
area.Name = "myGraph";
area.AxisX.Minimum = Xmin;
area.AxisY.Maximum = Xmax;
area.AxisX.MajorGrid.Interval = step_x;
area.AxisY.Minimum = Ymin;
area.AxisY.Maximum = Ymax;
area.AxisY.MajorGrid.Interval = step_y;
chart1.ChartAreas.Add(area);
Series series_0 = new Series();
series_0.ChartArea = "myGraph";
series_0.ChartType = SeriesChartType.Point;
series_0.MarkerSize = 10;
series_0.LegendText = "P(x)_0";
chart1.Series.Add(series_0);
Series series_1 = new Series();
series_1.ChartArea = "myGraph";
series_1.ChartType = SeriesChartType.Spline;
series_1.BorderWidth = 3;
series_1.LegendText = "P(x)_1";
chart1.Series.Add(series_1);
Series series_2 = new Series();
series_2.ChartArea = "myGraph";
series_2.ChartType = SeriesChartType.Spline;
series_2.BorderWidth = 3;
series_2.LegendText = "P(x)_2";
chart1.Series.Add(series_2);
Series series_p = new Series();
series_p.ChartArea = "myGraph";
series_p.ChartType = SeriesChartType.Spline;
series_p.BorderWidth = 3;
series_p.LegendText = "P(x)_precise";
chart1.Series.Add(series_p);
Legend legend = new Legend();
chart1.Legends.Add(legend);
chart1.Series[0].Points.DataBindXY(x, y);
chart1.Series[1].Points.DataBindXY(x, y_1);
chart1.Series[2].Points.DataBindXY(x, y_2);
chart1.Series[3].Points.DataBindXY(x, y_p);
}