private void ShowError()
{
double error = Math.Sqrt(
CurveFunctions.ErrorSquared(Points, BestCoeffs));
txtError.Text = error.ToString();
}
private void btnFit_Click(object sender, EventArgs e)
{
this.Cursor = Cursors.WaitCursor;
txtCoeffs.Clear();
txtError.Clear();
Application.DoEvents();
DateTime start_time = DateTime.Now;
int degree = (int)nudDegree.Value;
BestCoeffs = CurveFunctions.FindPolynomialLeastSquaresFit(Points, degree);
HasSolution = true;
DateTime stop_time = DateTime.Now;
TimeSpan elapsed = stop_time - start_time;
Console.WriteLine("Time: " +
elapsed.TotalSeconds.ToString("0.00") + " seconds");
string txt = "";
foreach (double coeff in BestCoeffs)
{
txt += " " + coeff.ToString();
}
txtCoeffs.Text = txt.Substring(1);
ShowError();
HasSolution = true;
picGraph.Refresh();
this.Cursor = Cursors.Default;
}
private void picGraph_Paint(object sender, PaintEventArgs e)
{
e.Graphics.Transform = DrawingTransform;
e.Graphics.SmoothingMode = SmoothingMode.AntiAlias;
DrawAxes(e.Graphics);
if (HasSolution)
{
using (Pen thin_pen = new Pen(Color.Blue, 0))
{
const double x_step = 0.1;
double y0 = CurveFunctions.F(BestCoeffs, Xmin);
for (double x = Xmin + x_step; x <= Xmax; x += x_step)
{
double y1 = CurveFunctions.F(BestCoeffs, x);
e.Graphics.DrawLine(thin_pen,
(float)(x - x_step), (float)y0, (float)x, (float)y1);
y0 = y1;
}
}
}
const float dx = (Xmax - Xmin) / 100;
const float dy = (Ymax - Ymin) / 100;
using (Pen thin_pen = new Pen(Color.Black, 0))
{
foreach (PointF pt in Points)
{
e.Graphics.FillRectangle(Brushes.White,
pt.X - dx, pt.Y - dy, 2 * dx, 2 * dy);
e.Graphics.DrawRectangle(thin_pen,
pt.X - dx, pt.Y - dy, 2 * dx, 2 * dy);
}
}
}
