/// <summary>
/// Interpolates between x and y points
/// </summary>
/// <param name="x">X coordinate of points</param>
/// <param name="y">Y coordinate of points </param>
/// <param name="xs">X coordinats of output. has to have output length</param>
/// <returns>a double array with Y coordinates</returns>
public static double[] Do(double[] x, double[] y, double[] xs)
{
if (x == null || y == null || xs == null) { throw new ArgumentNullException(); }
if (xs.Length <= x.Length) { throw new ArgumentException("xs has to be longer than x/y"); }
CubicSpline Spline = new CubicSpline();
return Spline.FitAndEval(x, y, xs);
}
/// <summary>
/// Interpolates between x and y points
/// </summary>
/// <param name="x">X coordinate of points</param>
/// <param name="y">Y coordinate of points </param>
/// <param name="length">length of output point array</param>
/// <returns>a point array with interpolated points</returns>
public static double[] Do(double[] x, double[] y, int length)
{
if (x == null || y == null) { throw new ArgumentNullException(); }
CubicSpline Spline = new CubicSpline();
//PointD[] Output = new PointD[length];
double[] xs = new double[length];
//double[] ys;
double d = Math.Abs(x[0] - x[x.Length - 1]);
for (int i = 0; i < length; i++) { xs[i] = i * d / (double)(length - 1); }
return Spline.FitAndEval(x, y, xs);
//for (int i = 0; i < length; i++) { Output[i] = new PointD((float)xs[i], (float)ys[i]); }
//return Output;
}
/// <summary>
/// Interpolates between a set of points
/// </summary>
/// <param name="points">a set of points to interpolate</param>
/// <param name="length">length of output point array</param>
/// <returns>a point array with interpolated points</returns>
public static PointD[] Do(PointD[] points, int length)
{
if (points == null) { throw new ArgumentNullException(); }
CubicSpline Spline = new CubicSpline();
PointD[] Output = new PointD[length];
double[] xs = new double[length];
double[] x = new double[points.Length];
double[] y = new double[points.Length];
double[] ys;
double d = Math.Abs(points[0].X - points[points.Length - 1].X);
for (int i = 0; i < length; i++) { xs[i] = i * d / (double)(length - 1); }
for (int i = 0; i < points.Length; i++) { x[i] = points[i].X; y[i] = points[i].Y; }
ys = Spline.FitAndEval(x, y, xs);
for (int i = 0; i < length; i++) { Output[i] = new PointD((float)xs[i], (float)ys[i]); }
return Output;
}