Ejemplo n.º 1
0
Archivo: Filter.cs Proyecto: m4mm0n/HGE
        /// <summary>
        /// Evaluation of complete interpolating function. Note that since each curve
        /// segment is controlled by four points, the end points will not be
        /// interpolated. If extra control points are not desirable, the end points
        /// can simply be repeated to ensure interpolation. Note also that points of
        /// non-differentiability and discontinuity can be introduced by repeating
        /// points
        /// </summary>
        /// <param name="f0_base"></param>
        /// <param name="p0"></param>
        /// <param name="pn"></param>
        /// <param name="plotter"></param>
        /// <param name="res"></param>
        public void interpolate(int[][] f0_base, int p0, int pn, PointPlotter plotter, double res)
        {
            double k1, k2;

            // Set up points for first curve segment.
            int p1 = p0;

            ++p1;
            int p2 = p1;

            ++p2;
            int p3 = p2;

            ++p3;

            // Draw each curve segment.
            for (; p2 != pn; ++p0, ++p1, ++p2, ++p3)
            {
                // p1 and p2 equal; single point.
                if (x(f0_base, p1) == x(f0_base, p2))
                {
                    continue;
                }
                // Both end points repeated; straight line.
                if (x(f0_base, p0) == x(f0_base, p1) && x(f0_base, p2) == x(f0_base, p3))
                {
                    k1 = k2 = (y(f0_base, p2) - y(f0_base, p1)) / (x(f0_base, p2) - x(f0_base, p1));
                }
                // p0 and p1 equal; use f''(x1) = 0.
                else if (x(f0_base, p0) == x(f0_base, p1))
                {
                    k2 = (y(f0_base, p3) - y(f0_base, p1)) / (x(f0_base, p3) - x(f0_base, p1));
                    k1 = (3 * (y(f0_base, p2) - y(f0_base, p1)) / (x(f0_base, p2) - x(f0_base, p1)) - k2) / 2;
                }
                // p2 and p3 equal; use f''(x2) = 0.
                else if (x(f0_base, p2) == x(f0_base, p3))
                {
                    k1 = (y(f0_base, p2) - y(f0_base, p0)) / (x(f0_base, p2) - x(f0_base, p0));
                    k2 = (3 * (y(f0_base, p2) - y(f0_base, p1)) / (x(f0_base, p2) - x(f0_base, p1)) - k1) / 2;
                }
                // Normal curve.
                else
                {
                    k1 = (y(f0_base, p2) - y(f0_base, p0)) / (x(f0_base, p2) - x(f0_base, p0));
                    k2 = (y(f0_base, p3) - y(f0_base, p1)) / (x(f0_base, p3) - x(f0_base, p1));
                }

#if SPLINE_BRUTE_FORCE
                {
                    interpolate_brute_force(x(f0_base, p1), y(f0_base, p1), x(f0_base, p2), y(f0_base, p2), k1, k2, plotter, res);
                }
#else
                {
                    interpolate_forward_difference(x(f0_base, p1), y(f0_base, p1), x(f0_base, p2), y(f0_base, p2), k1, k2, plotter, res);
                }
#endif
            }
        }
Ejemplo n.º 2
0
Archivo: Filter.cs Proyecto: m4mm0n/HGE
        /// <summary>
        /// Evaluation of cubic polynomial by forward differencing
        /// </summary>
        /// <param name="x1"></param>
        /// <param name="y1"></param>
        /// <param name="x2"></param>
        /// <param name="y2"></param>
        /// <param name="k1"></param>
        /// <param name="k2"></param>
        /// <param name="plotter"></param>
        /// <param name="res"></param>
        protected void interpolate_forward_difference(double x1, double y1, double x2, double y2, double k1, double k2, PointPlotter plotter, double res)
        {
            Coefficients coeff = new Coefficients();

            cubic_coefficients(x1, y1, x2, y2, k1, k2, coeff);

            double y   = ((coeff.a * x1 + coeff.b) * x1 + coeff.c) * x1 + coeff.d;
            double dy  = (3 * coeff.a * (x1 + res) + 2 * coeff.b) * x1 * res + ((coeff.a * res + coeff.b) * res + coeff.c) * res;
            double d2y = (6 * coeff.a * (x1 + res) + 2 * coeff.b) * res * res;
            double d3y = 6 * coeff.a * res * res * res;

            // Calculate each point
            for (double x = x1; x <= x2; x += res)
            {
                plotter.plot(x, y);
                y   += dy;
                dy  += d2y;
                d2y += d3y;
            }
        }
Ejemplo n.º 3
0
Archivo: Filter.cs Proyecto: m4mm0n/HGE
        /// <summary>
        /// Evaluation of cubic polynomial by brute force
        /// </summary>
        /// <param name="x1"></param>
        /// <param name="y1"></param>
        /// <param name="x2"></param>
        /// <param name="y2"></param>
        /// <param name="k1"></param>
        /// <param name="k2"></param>
        /// <param name="plotter"></param>
        /// <param name="res"></param>
        protected void interpolate_brute_force(double x1, double y1, double x2, double y2, double k1, double k2, PointPlotter plotter, double res)
        {
            Coefficients coeff = new Coefficients();

            cubic_coefficients(x1, y1, x2, y2, k1, k2, coeff);

            // Calculate each point
            for (double x = x1; x <= x2; x += res)
            {
                double y = ((coeff.a * x + coeff.b) * x + coeff.c) * x + coeff.d;
                plotter.plot(x, y);
            }
        }