[2806] | 1 | /*************************************************************************
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| 2 | Copyright (c) 2007, Sergey Bochkanov (ALGLIB project).
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| 3 |
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| 4 | >>> SOURCE LICENSE >>>
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| 5 | This program is free software; you can redistribute it and/or modify
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| 6 | it under the terms of the GNU General Public License as published by
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| 7 | the Free Software Foundation (www.fsf.org); either version 2 of the
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| 8 | License, or (at your option) any later version.
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| 9 |
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| 10 | This program is distributed in the hope that it will be useful,
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| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of
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| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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| 13 | GNU General Public License for more details.
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| 14 |
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| 15 | A copy of the GNU General Public License is available at
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| 16 | http://www.fsf.org/licensing/licenses
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| 17 |
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| 18 | >>> END OF LICENSE >>>
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| 19 | *************************************************************************/
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| 20 |
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| 21 | using System;
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| 22 |
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| 23 | namespace alglib
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| 24 | {
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| 25 | public class spline3
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| 26 | {
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| 27 | public static void buildlinearspline(double[] x,
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| 28 | double[] y,
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| 29 | int n,
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| 30 | ref double[] c)
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| 31 | {
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| 32 | int i = 0;
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| 33 | int tblsize = 0;
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| 34 |
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| 35 | x = (double[])x.Clone();
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| 36 | y = (double[])y.Clone();
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| 37 |
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| 38 | System.Diagnostics.Debug.Assert(n>=2, "BuildLinearSpline: N<2!");
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| 39 |
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| 40 | //
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| 41 | // Sort points
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| 42 | //
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| 43 | heapsortpoints(ref x, ref y, n);
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| 44 |
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| 45 | //
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| 46 | // Fill C:
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| 47 | // C[0] - length(C)
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| 48 | // C[1] - type(C):
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| 49 | // 3 - general cubic spline
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| 50 | // C[2] - N
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| 51 | // C[3]...C[3+N-1] - x[i], i = 0...N-1
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| 52 | // C[3+N]...C[3+N+(N-1)*4-1] - coefficients table
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| 53 | //
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| 54 | tblsize = 3+n+(n-1)*4;
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| 55 | c = new double[tblsize-1+1];
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| 56 | c[0] = tblsize;
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| 57 | c[1] = 3;
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| 58 | c[2] = n;
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| 59 | for(i=0; i<=n-1; i++)
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| 60 | {
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| 61 | c[3+i] = x[i];
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| 62 | }
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| 63 | for(i=0; i<=n-2; i++)
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| 64 | {
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| 65 | c[3+n+4*i+0] = y[i];
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| 66 | c[3+n+4*i+1] = (y[i+1]-y[i])/(x[i+1]-x[i]);
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| 67 | c[3+n+4*i+2] = 0;
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| 68 | c[3+n+4*i+3] = 0;
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| 69 | }
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| 70 | }
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| 71 |
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| 72 |
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| 73 | public static void buildcubicspline(double[] x,
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| 74 | double[] y,
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| 75 | int n,
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| 76 | int boundltype,
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| 77 | double boundl,
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| 78 | int boundrtype,
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| 79 | double boundr,
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| 80 | ref double[] c)
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| 81 | {
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| 82 | double[] a1 = new double[0];
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| 83 | double[] a2 = new double[0];
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| 84 | double[] a3 = new double[0];
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| 85 | double[] b = new double[0];
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| 86 | double[] d = new double[0];
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| 87 | int i = 0;
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| 88 | int tblsize = 0;
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| 89 | double delta = 0;
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| 90 | double delta2 = 0;
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| 91 | double delta3 = 0;
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| 92 |
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| 93 | x = (double[])x.Clone();
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| 94 | y = (double[])y.Clone();
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| 95 |
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| 96 | System.Diagnostics.Debug.Assert(n>=2, "BuildCubicSpline: N<2!");
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| 97 | System.Diagnostics.Debug.Assert(boundltype==0 | boundltype==1 | boundltype==2, "BuildCubicSpline: incorrect BoundLType!");
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| 98 | System.Diagnostics.Debug.Assert(boundrtype==0 | boundrtype==1 | boundrtype==2, "BuildCubicSpline: incorrect BoundRType!");
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| 99 | a1 = new double[n-1+1];
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| 100 | a2 = new double[n-1+1];
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| 101 | a3 = new double[n-1+1];
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| 102 | b = new double[n-1+1];
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| 103 |
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| 104 | //
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| 105 | // Special case:
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| 106 | // * N=2
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| 107 | // * parabolic terminated boundary condition on both ends
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| 108 | //
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| 109 | if( n==2 & boundltype==0 & boundrtype==0 )
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| 110 | {
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| 111 |
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| 112 | //
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| 113 | // Change task type
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| 114 | //
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| 115 | boundltype = 2;
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| 116 | boundl = 0;
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| 117 | boundrtype = 2;
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| 118 | boundr = 0;
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| 119 | }
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| 120 |
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| 121 | //
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| 122 | //
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| 123 | // Sort points
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| 124 | //
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| 125 | heapsortpoints(ref x, ref y, n);
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| 126 |
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| 127 | //
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| 128 | // Left boundary conditions
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| 129 | //
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| 130 | if( boundltype==0 )
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| 131 | {
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| 132 | a1[0] = 0;
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| 133 | a2[0] = 1;
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| 134 | a3[0] = 1;
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| 135 | b[0] = 2*(y[1]-y[0])/(x[1]-x[0]);
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| 136 | }
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| 137 | if( boundltype==1 )
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| 138 | {
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| 139 | a1[0] = 0;
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| 140 | a2[0] = 1;
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| 141 | a3[0] = 0;
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| 142 | b[0] = boundl;
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| 143 | }
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| 144 | if( boundltype==2 )
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| 145 | {
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| 146 | a1[0] = 0;
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| 147 | a2[0] = 2;
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| 148 | a3[0] = 1;
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| 149 | b[0] = 3*(y[1]-y[0])/(x[1]-x[0])-0.5*boundl*(x[1]-x[0]);
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| 150 | }
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| 151 |
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| 152 | //
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| 153 | // Central conditions
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| 154 | //
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| 155 | for(i=1; i<=n-2; i++)
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| 156 | {
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| 157 | a1[i] = x[i+1]-x[i];
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| 158 | a2[i] = 2*(x[i+1]-x[i-1]);
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| 159 | a3[i] = x[i]-x[i-1];
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| 160 | b[i] = 3*(y[i]-y[i-1])/(x[i]-x[i-1])*(x[i+1]-x[i])+3*(y[i+1]-y[i])/(x[i+1]-x[i])*(x[i]-x[i-1]);
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| 161 | }
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| 162 |
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| 163 | //
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| 164 | // Right boundary conditions
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| 165 | //
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| 166 | if( boundrtype==0 )
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| 167 | {
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| 168 | a1[n-1] = 1;
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| 169 | a2[n-1] = 1;
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| 170 | a3[n-1] = 0;
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| 171 | b[n-1] = 2*(y[n-1]-y[n-2])/(x[n-1]-x[n-2]);
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| 172 | }
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| 173 | if( boundrtype==1 )
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| 174 | {
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| 175 | a1[n-1] = 0;
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| 176 | a2[n-1] = 1;
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| 177 | a3[n-1] = 0;
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| 178 | b[n-1] = boundr;
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| 179 | }
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| 180 | if( boundrtype==2 )
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| 181 | {
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| 182 | a1[n-1] = 1;
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| 183 | a2[n-1] = 2;
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| 184 | a3[n-1] = 0;
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| 185 | b[n-1] = 3*(y[n-1]-y[n-2])/(x[n-1]-x[n-2])+0.5*boundr*(x[n-1]-x[n-2]);
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| 186 | }
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| 187 |
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| 188 | //
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| 189 | // Solve
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| 190 | //
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| 191 | solvetridiagonal(a1, a2, a3, b, n, ref d);
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| 192 |
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| 193 | //
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| 194 | // Now problem is reduced to the cubic Hermite spline
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| 195 | //
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| 196 | buildhermitespline(x, y, d, n, ref c);
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| 197 | }
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| 198 |
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| 199 |
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| 200 | public static void buildhermitespline(double[] x,
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| 201 | double[] y,
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| 202 | double[] d,
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| 203 | int n,
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| 204 | ref double[] c)
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| 205 | {
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| 206 | int i = 0;
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| 207 | int tblsize = 0;
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| 208 | double delta = 0;
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| 209 | double delta2 = 0;
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| 210 | double delta3 = 0;
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| 211 |
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| 212 | x = (double[])x.Clone();
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| 213 | y = (double[])y.Clone();
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| 214 | d = (double[])d.Clone();
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| 215 |
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| 216 | System.Diagnostics.Debug.Assert(n>=2, "BuildHermiteSpline: N<2!");
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| 217 |
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| 218 | //
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| 219 | // Sort points
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| 220 | //
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| 221 | heapsortdpoints(ref x, ref y, ref d, n);
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| 222 |
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| 223 | //
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| 224 | // Fill C:
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| 225 | // C[0] - length(C)
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| 226 | // C[1] - type(C):
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| 227 | // 3 - general cubic spline
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| 228 | // C[2] - N
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| 229 | // C[3]...C[3+N-1] - x[i], i = 0...N-1
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| 230 | // C[3+N]...C[3+N+(N-1)*4-1] - coefficients table
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| 231 | //
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| 232 | tblsize = 3+n+(n-1)*4;
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| 233 | c = new double[tblsize-1+1];
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| 234 | c[0] = tblsize;
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| 235 | c[1] = 3;
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| 236 | c[2] = n;
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| 237 | for(i=0; i<=n-1; i++)
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| 238 | {
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| 239 | c[3+i] = x[i];
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| 240 | }
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| 241 | for(i=0; i<=n-2; i++)
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| 242 | {
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| 243 | delta = x[i+1]-x[i];
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| 244 | delta2 = AP.Math.Sqr(delta);
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| 245 | delta3 = delta*delta2;
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| 246 | c[3+n+4*i+0] = y[i];
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| 247 | c[3+n+4*i+1] = d[i];
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| 248 | c[3+n+4*i+2] = (3*(y[i+1]-y[i])-2*d[i]*delta-d[i+1]*delta)/delta2;
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| 249 | c[3+n+4*i+3] = (2*(y[i]-y[i+1])+d[i]*delta+d[i+1]*delta)/delta3;
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| 250 | }
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| 251 | }
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| 252 |
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| 253 |
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| 254 | public static void buildakimaspline(double[] x,
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| 255 | double[] y,
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| 256 | int n,
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| 257 | ref double[] c)
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| 258 | {
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| 259 | int i = 0;
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| 260 | double[] d = new double[0];
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| 261 | double[] w = new double[0];
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| 262 | double[] diff = new double[0];
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| 263 |
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| 264 | x = (double[])x.Clone();
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| 265 | y = (double[])y.Clone();
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| 266 |
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| 267 | System.Diagnostics.Debug.Assert(n>=5, "BuildAkimaSpline: N<5!");
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| 268 |
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| 269 | //
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| 270 | // Sort points
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| 271 | //
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| 272 | heapsortpoints(ref x, ref y, n);
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| 273 |
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| 274 | //
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| 275 | // Prepare W (weights), Diff (divided differences)
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| 276 | //
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| 277 | w = new double[n-2+1];
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| 278 | diff = new double[n-2+1];
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| 279 | for(i=0; i<=n-2; i++)
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| 280 | {
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| 281 | diff[i] = (y[i+1]-y[i])/(x[i+1]-x[i]);
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| 282 | }
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| 283 | for(i=1; i<=n-2; i++)
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| 284 | {
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| 285 | w[i] = Math.Abs(diff[i]-diff[i-1]);
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| 286 | }
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| 287 |
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| 288 | //
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| 289 | // Prepare Hermite interpolation scheme
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| 290 | //
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| 291 | d = new double[n-1+1];
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| 292 | for(i=2; i<=n-3; i++)
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| 293 | {
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| 294 | if( (double)(Math.Abs(w[i-1])+Math.Abs(w[i+1]))!=(double)(0) )
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| 295 | {
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| 296 | d[i] = (w[i+1]*diff[i-1]+w[i-1]*diff[i])/(w[i+1]+w[i-1]);
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| 297 | }
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| 298 | else
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| 299 | {
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| 300 | d[i] = ((x[i+1]-x[i])*diff[i-1]+(x[i]-x[i-1])*diff[i])/(x[i+1]-x[i-1]);
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| 301 | }
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| 302 | }
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| 303 | d[0] = diffthreepoint(x[0], x[0], y[0], x[1], y[1], x[2], y[2]);
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| 304 | d[1] = diffthreepoint(x[1], x[0], y[0], x[1], y[1], x[2], y[2]);
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| 305 | d[n-2] = diffthreepoint(x[n-2], x[n-3], y[n-3], x[n-2], y[n-2], x[n-1], y[n-1]);
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| 306 | d[n-1] = diffthreepoint(x[n-1], x[n-3], y[n-3], x[n-2], y[n-2], x[n-1], y[n-1]);
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| 307 |
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| 308 | //
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| 309 | // Build Akima spline using Hermite interpolation scheme
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| 310 | //
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| 311 | buildhermitespline(x, y, d, n, ref c);
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| 312 | }
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| 313 |
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| 314 |
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| 315 | public static double splineinterpolation(ref double[] c,
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| 316 | double x)
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| 317 | {
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| 318 | double result = 0;
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| 319 | int n = 0;
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| 320 | int l = 0;
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| 321 | int r = 0;
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| 322 | int m = 0;
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| 323 |
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| 324 | System.Diagnostics.Debug.Assert((int)Math.Round(c[1])==3, "SplineInterpolation: incorrect C!");
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| 325 | n = (int)Math.Round(c[2]);
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| 326 |
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| 327 | //
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| 328 | // Binary search in the [ x[0], ..., x[n-2] ] (x[n-1] is not included)
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| 329 | //
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| 330 | l = 3;
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| 331 | r = 3+n-2+1;
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| 332 | while( l!=r-1 )
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| 333 | {
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| 334 | m = (l+r)/2;
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| 335 | if( (double)(c[m])>=(double)(x) )
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| 336 | {
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| 337 | r = m;
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| 338 | }
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| 339 | else
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| 340 | {
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| 341 | l = m;
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| 342 | }
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| 343 | }
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| 344 |
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| 345 | //
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| 346 | // Interpolation
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| 347 | //
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| 348 | x = x-c[l];
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| 349 | m = 3+n+4*(l-3);
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| 350 | result = c[m]+x*(c[m+1]+x*(c[m+2]+x*c[m+3]));
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| 351 | return result;
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| 352 | }
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| 353 |
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| 354 |
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| 355 | public static void splinedifferentiation(ref double[] c,
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| 356 | double x,
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| 357 | ref double s,
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| 358 | ref double ds,
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| 359 | ref double d2s)
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| 360 | {
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| 361 | int n = 0;
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| 362 | int l = 0;
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| 363 | int r = 0;
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| 364 | int m = 0;
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| 365 |
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| 366 | System.Diagnostics.Debug.Assert((int)Math.Round(c[1])==3, "SplineInterpolation: incorrect C!");
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| 367 | n = (int)Math.Round(c[2]);
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| 368 |
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| 369 | //
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| 370 | // Binary search
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| 371 | //
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| 372 | l = 3;
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| 373 | r = 3+n-2+1;
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| 374 | while( l!=r-1 )
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| 375 | {
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| 376 | m = (l+r)/2;
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| 377 | if( (double)(c[m])>=(double)(x) )
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| 378 | {
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| 379 | r = m;
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| 380 | }
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| 381 | else
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| 382 | {
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| 383 | l = m;
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| 384 | }
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| 385 | }
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| 386 |
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| 387 | //
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| 388 | // Differentiation
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| 389 | //
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| 390 | x = x-c[l];
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| 391 | m = 3+n+4*(l-3);
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| 392 | s = c[m]+x*(c[m+1]+x*(c[m+2]+x*c[m+3]));
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| 393 | ds = c[m+1]+2*x*c[m+2]+3*AP.Math.Sqr(x)*c[m+3];
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| 394 | d2s = 2*c[m+2]+6*x*c[m+3];
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| 395 | }
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| 396 |
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| 397 |
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| 398 | public static void splinecopy(ref double[] c,
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| 399 | ref double[] cc)
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| 400 | {
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| 401 | int s = 0;
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| 402 | int i_ = 0;
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| 403 |
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| 404 | s = (int)Math.Round(c[0]);
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| 405 | cc = new double[s-1+1];
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| 406 | for(i_=0; i_<=s-1;i_++)
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| 407 | {
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| 408 | cc[i_] = c[i_];
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| 409 | }
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| 410 | }
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| 411 |
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| 412 |
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| 413 | public static void splineunpack(ref double[] c,
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| 414 | ref int n,
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| 415 | ref double[,] tbl)
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| 416 | {
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| 417 | int i = 0;
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| 418 |
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| 419 | System.Diagnostics.Debug.Assert((int)Math.Round(c[1])==3, "SplineUnpack: incorrect C!");
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| 420 | n = (int)Math.Round(c[2]);
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| 421 | tbl = new double[n-2+1, 5+1];
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| 422 |
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| 423 | //
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| 424 | // Fill
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| 425 | //
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| 426 | for(i=0; i<=n-2; i++)
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| 427 | {
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| 428 | tbl[i,0] = c[3+i];
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| 429 | tbl[i,1] = c[3+i+1];
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| 430 | tbl[i,2] = c[3+n+4*i];
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| 431 | tbl[i,3] = c[3+n+4*i+1];
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| 432 | tbl[i,4] = c[3+n+4*i+2];
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| 433 | tbl[i,5] = c[3+n+4*i+3];
|
---|
| 434 | }
|
---|
| 435 | }
|
---|
| 436 |
|
---|
| 437 |
|
---|
| 438 | public static void splinelintransx(ref double[] c,
|
---|
| 439 | double a,
|
---|
| 440 | double b)
|
---|
| 441 | {
|
---|
| 442 | int i = 0;
|
---|
| 443 | int n = 0;
|
---|
| 444 | double v = 0;
|
---|
| 445 | double dv = 0;
|
---|
| 446 | double d2v = 0;
|
---|
| 447 | double[] x = new double[0];
|
---|
| 448 | double[] y = new double[0];
|
---|
| 449 | double[] d = new double[0];
|
---|
| 450 |
|
---|
| 451 | System.Diagnostics.Debug.Assert((int)Math.Round(c[1])==3, "SplineLinTransX: incorrect C!");
|
---|
| 452 | n = (int)Math.Round(c[2]);
|
---|
| 453 |
|
---|
| 454 | //
|
---|
| 455 | // Special case: A=0
|
---|
| 456 | //
|
---|
| 457 | if( (double)(a)==(double)(0) )
|
---|
| 458 | {
|
---|
| 459 | v = splineinterpolation(ref c, b);
|
---|
| 460 | for(i=0; i<=n-2; i++)
|
---|
| 461 | {
|
---|
| 462 | c[3+n+4*i] = v;
|
---|
| 463 | c[3+n+4*i+1] = 0;
|
---|
| 464 | c[3+n+4*i+2] = 0;
|
---|
| 465 | c[3+n+4*i+3] = 0;
|
---|
| 466 | }
|
---|
| 467 | return;
|
---|
| 468 | }
|
---|
| 469 |
|
---|
| 470 | //
|
---|
| 471 | // General case: A<>0.
|
---|
| 472 | // Unpack, X, Y, dY/dX.
|
---|
| 473 | // Scale and pack again.
|
---|
| 474 | //
|
---|
| 475 | x = new double[n-1+1];
|
---|
| 476 | y = new double[n-1+1];
|
---|
| 477 | d = new double[n-1+1];
|
---|
| 478 | for(i=0; i<=n-1; i++)
|
---|
| 479 | {
|
---|
| 480 | x[i] = c[3+i];
|
---|
| 481 | splinedifferentiation(ref c, x[i], ref v, ref dv, ref d2v);
|
---|
| 482 | x[i] = (x[i]-b)/a;
|
---|
| 483 | y[i] = v;
|
---|
| 484 | d[i] = a*dv;
|
---|
| 485 | }
|
---|
| 486 | buildhermitespline(x, y, d, n, ref c);
|
---|
| 487 | }
|
---|
| 488 |
|
---|
| 489 |
|
---|
| 490 | public static void splinelintransy(ref double[] c,
|
---|
| 491 | double a,
|
---|
| 492 | double b)
|
---|
| 493 | {
|
---|
| 494 | int i = 0;
|
---|
| 495 | int n = 0;
|
---|
| 496 | double v = 0;
|
---|
| 497 | double dv = 0;
|
---|
| 498 | double d2v = 0;
|
---|
| 499 | double[] x = new double[0];
|
---|
| 500 | double[] y = new double[0];
|
---|
| 501 | double[] d = new double[0];
|
---|
| 502 |
|
---|
| 503 | System.Diagnostics.Debug.Assert((int)Math.Round(c[1])==3, "SplineLinTransX: incorrect C!");
|
---|
| 504 | n = (int)Math.Round(c[2]);
|
---|
| 505 |
|
---|
| 506 | //
|
---|
| 507 | // Special case: A=0
|
---|
| 508 | //
|
---|
| 509 | for(i=0; i<=n-2; i++)
|
---|
| 510 | {
|
---|
| 511 | c[3+n+4*i] = a*c[3+n+4*i]+b;
|
---|
| 512 | c[3+n+4*i+1] = a*c[3+n+4*i+1];
|
---|
| 513 | c[3+n+4*i+2] = a*c[3+n+4*i+2];
|
---|
| 514 | c[3+n+4*i+3] = a*c[3+n+4*i+3];
|
---|
| 515 | }
|
---|
| 516 | }
|
---|
| 517 |
|
---|
| 518 |
|
---|
| 519 | public static double splineintegration(ref double[] c,
|
---|
| 520 | double x)
|
---|
| 521 | {
|
---|
| 522 | double result = 0;
|
---|
| 523 | int n = 0;
|
---|
| 524 | int i = 0;
|
---|
| 525 | int l = 0;
|
---|
| 526 | int r = 0;
|
---|
| 527 | int m = 0;
|
---|
| 528 | double w = 0;
|
---|
| 529 |
|
---|
| 530 | System.Diagnostics.Debug.Assert((int)Math.Round(c[1])==3, "SplineIntegration: incorrect C!");
|
---|
| 531 | n = (int)Math.Round(c[2]);
|
---|
| 532 |
|
---|
| 533 | //
|
---|
| 534 | // Binary search in the [ x[0], ..., x[n-2] ] (x[n-1] is not included)
|
---|
| 535 | //
|
---|
| 536 | l = 3;
|
---|
| 537 | r = 3+n-2+1;
|
---|
| 538 | while( l!=r-1 )
|
---|
| 539 | {
|
---|
| 540 | m = (l+r)/2;
|
---|
| 541 | if( (double)(c[m])>=(double)(x) )
|
---|
| 542 | {
|
---|
| 543 | r = m;
|
---|
| 544 | }
|
---|
| 545 | else
|
---|
| 546 | {
|
---|
| 547 | l = m;
|
---|
| 548 | }
|
---|
| 549 | }
|
---|
| 550 |
|
---|
| 551 | //
|
---|
| 552 | // Integration
|
---|
| 553 | //
|
---|
| 554 | result = 0;
|
---|
| 555 | for(i=3; i<=l-1; i++)
|
---|
| 556 | {
|
---|
| 557 | w = c[i+1]-c[i];
|
---|
| 558 | m = 3+n+4*(i-3);
|
---|
| 559 | result = result+c[m]*w;
|
---|
| 560 | result = result+c[m+1]*AP.Math.Sqr(w)/2;
|
---|
| 561 | result = result+c[m+2]*AP.Math.Sqr(w)*w/3;
|
---|
| 562 | result = result+c[m+3]*AP.Math.Sqr(AP.Math.Sqr(w))/4;
|
---|
| 563 | }
|
---|
| 564 | w = x-c[l];
|
---|
| 565 | m = 3+n+4*(l-3);
|
---|
| 566 | result = result+c[m]*w;
|
---|
| 567 | result = result+c[m+1]*AP.Math.Sqr(w)/2;
|
---|
| 568 | result = result+c[m+2]*AP.Math.Sqr(w)*w/3;
|
---|
| 569 | result = result+c[m+3]*AP.Math.Sqr(AP.Math.Sqr(w))/4;
|
---|
| 570 | return result;
|
---|
| 571 | }
|
---|
| 572 |
|
---|
| 573 |
|
---|
| 574 | public static void spline3buildtable(int n,
|
---|
| 575 | int diffn,
|
---|
| 576 | double[] x,
|
---|
| 577 | double[] y,
|
---|
| 578 | double boundl,
|
---|
| 579 | double boundr,
|
---|
| 580 | ref double[,] ctbl)
|
---|
| 581 | {
|
---|
| 582 | bool c = new bool();
|
---|
| 583 | int e = 0;
|
---|
| 584 | int g = 0;
|
---|
| 585 | double tmp = 0;
|
---|
| 586 | int nxm1 = 0;
|
---|
| 587 | int i = 0;
|
---|
| 588 | int j = 0;
|
---|
| 589 | double dx = 0;
|
---|
| 590 | double dxj = 0;
|
---|
| 591 | double dyj = 0;
|
---|
| 592 | double dxjp1 = 0;
|
---|
| 593 | double dyjp1 = 0;
|
---|
| 594 | double dxp = 0;
|
---|
| 595 | double dyp = 0;
|
---|
| 596 | double yppa = 0;
|
---|
| 597 | double yppb = 0;
|
---|
| 598 | double pj = 0;
|
---|
| 599 | double b1 = 0;
|
---|
| 600 | double b2 = 0;
|
---|
| 601 | double b3 = 0;
|
---|
| 602 | double b4 = 0;
|
---|
| 603 |
|
---|
| 604 | x = (double[])x.Clone();
|
---|
| 605 | y = (double[])y.Clone();
|
---|
| 606 |
|
---|
| 607 | n = n-1;
|
---|
| 608 | g = (n+1)/2;
|
---|
| 609 | do
|
---|
| 610 | {
|
---|
| 611 | i = g;
|
---|
| 612 | do
|
---|
| 613 | {
|
---|
| 614 | j = i-g;
|
---|
| 615 | c = true;
|
---|
| 616 | do
|
---|
| 617 | {
|
---|
| 618 | if( (double)(x[j])<=(double)(x[j+g]) )
|
---|
| 619 | {
|
---|
| 620 | c = false;
|
---|
| 621 | }
|
---|
| 622 | else
|
---|
| 623 | {
|
---|
| 624 | tmp = x[j];
|
---|
| 625 | x[j] = x[j+g];
|
---|
| 626 | x[j+g] = tmp;
|
---|
| 627 | tmp = y[j];
|
---|
| 628 | y[j] = y[j+g];
|
---|
| 629 | y[j+g] = tmp;
|
---|
| 630 | }
|
---|
| 631 | j = j-1;
|
---|
| 632 | }
|
---|
| 633 | while( j>=0 & c );
|
---|
| 634 | i = i+1;
|
---|
| 635 | }
|
---|
| 636 | while( i<=n );
|
---|
| 637 | g = g/2;
|
---|
| 638 | }
|
---|
| 639 | while( g>0 );
|
---|
| 640 | ctbl = new double[4+1, n+1];
|
---|
| 641 | n = n+1;
|
---|
| 642 | if( diffn==1 )
|
---|
| 643 | {
|
---|
| 644 | b1 = 1;
|
---|
| 645 | b2 = 6/(x[1]-x[0])*((y[1]-y[0])/(x[1]-x[0])-boundl);
|
---|
| 646 | b3 = 1;
|
---|
| 647 | b4 = 6/(x[n-1]-x[n-2])*(boundr-(y[n-1]-y[n-2])/(x[n-1]-x[n-2]));
|
---|
| 648 | }
|
---|
| 649 | else
|
---|
| 650 | {
|
---|
| 651 | b1 = 0;
|
---|
| 652 | b2 = 2*boundl;
|
---|
| 653 | b3 = 0;
|
---|
| 654 | b4 = 2*boundr;
|
---|
| 655 | }
|
---|
| 656 | nxm1 = n-1;
|
---|
| 657 | if( n>=2 )
|
---|
| 658 | {
|
---|
| 659 | if( n>2 )
|
---|
| 660 | {
|
---|
| 661 | dxj = x[1]-x[0];
|
---|
| 662 | dyj = y[1]-y[0];
|
---|
| 663 | j = 2;
|
---|
| 664 | while( j<=nxm1 )
|
---|
| 665 | {
|
---|
| 666 | dxjp1 = x[j]-x[j-1];
|
---|
| 667 | dyjp1 = y[j]-y[j-1];
|
---|
| 668 | dxp = dxj+dxjp1;
|
---|
| 669 | ctbl[1,j-1] = dxjp1/dxp;
|
---|
| 670 | ctbl[2,j-1] = 1-ctbl[1,j-1];
|
---|
| 671 | ctbl[3,j-1] = 6*(dyjp1/dxjp1-dyj/dxj)/dxp;
|
---|
| 672 | dxj = dxjp1;
|
---|
| 673 | dyj = dyjp1;
|
---|
| 674 | j = j+1;
|
---|
| 675 | }
|
---|
| 676 | }
|
---|
| 677 | ctbl[1,0] = -(b1/2);
|
---|
| 678 | ctbl[2,0] = b2/2;
|
---|
| 679 | if( n!=2 )
|
---|
| 680 | {
|
---|
| 681 | j = 2;
|
---|
| 682 | while( j<=nxm1 )
|
---|
| 683 | {
|
---|
| 684 | pj = ctbl[2,j-1]*ctbl[1,j-2]+2;
|
---|
| 685 | ctbl[1,j-1] = -(ctbl[1,j-1]/pj);
|
---|
| 686 | ctbl[2,j-1] = (ctbl[3,j-1]-ctbl[2,j-1]*ctbl[2,j-2])/pj;
|
---|
| 687 | j = j+1;
|
---|
| 688 | }
|
---|
| 689 | }
|
---|
| 690 | yppb = (b4-b3*ctbl[2,nxm1-1])/(b3*ctbl[1,nxm1-1]+2);
|
---|
| 691 | i = 1;
|
---|
| 692 | while( i<=nxm1 )
|
---|
| 693 | {
|
---|
| 694 | j = n-i;
|
---|
| 695 | yppa = ctbl[1,j-1]*yppb+ctbl[2,j-1];
|
---|
| 696 | dx = x[j]-x[j-1];
|
---|
| 697 | ctbl[3,j-1] = (yppb-yppa)/dx/6;
|
---|
| 698 | ctbl[2,j-1] = yppa/2;
|
---|
| 699 | ctbl[1,j-1] = (y[j]-y[j-1])/dx-(ctbl[2,j-1]+ctbl[3,j-1]*dx)*dx;
|
---|
| 700 | yppb = yppa;
|
---|
| 701 | i = i+1;
|
---|
| 702 | }
|
---|
| 703 | for(i=1; i<=n; i++)
|
---|
| 704 | {
|
---|
| 705 | ctbl[0,i-1] = y[i-1];
|
---|
| 706 | ctbl[4,i-1] = x[i-1];
|
---|
| 707 | }
|
---|
| 708 | }
|
---|
| 709 | }
|
---|
| 710 |
|
---|
| 711 |
|
---|
| 712 | public static double spline3interpolate(int n,
|
---|
| 713 | ref double[,] c,
|
---|
| 714 | double x)
|
---|
| 715 | {
|
---|
| 716 | double result = 0;
|
---|
| 717 | int i = 0;
|
---|
| 718 | int l = 0;
|
---|
| 719 | int half = 0;
|
---|
| 720 | int first = 0;
|
---|
| 721 | int middle = 0;
|
---|
| 722 |
|
---|
| 723 | n = n-1;
|
---|
| 724 | l = n;
|
---|
| 725 | first = 0;
|
---|
| 726 | while( l>0 )
|
---|
| 727 | {
|
---|
| 728 | half = l/2;
|
---|
| 729 | middle = first+half;
|
---|
| 730 | if( (double)(c[4,middle])<(double)(x) )
|
---|
| 731 | {
|
---|
| 732 | first = middle+1;
|
---|
| 733 | l = l-half-1;
|
---|
| 734 | }
|
---|
| 735 | else
|
---|
| 736 | {
|
---|
| 737 | l = half;
|
---|
| 738 | }
|
---|
| 739 | }
|
---|
| 740 | i = first-1;
|
---|
| 741 | if( i<0 )
|
---|
| 742 | {
|
---|
| 743 | i = 0;
|
---|
| 744 | }
|
---|
| 745 | result = c[0,i]+(x-c[4,i])*(c[1,i]+(x-c[4,i])*(c[2,i]+c[3,i]*(x-c[4,i])));
|
---|
| 746 | return result;
|
---|
| 747 | }
|
---|
| 748 |
|
---|
| 749 |
|
---|
| 750 | private static void heapsortpoints(ref double[] x,
|
---|
| 751 | ref double[] y,
|
---|
| 752 | int n)
|
---|
| 753 | {
|
---|
| 754 | int i = 0;
|
---|
| 755 | int j = 0;
|
---|
| 756 | int k = 0;
|
---|
| 757 | int t = 0;
|
---|
| 758 | double tmp = 0;
|
---|
| 759 | bool isascending = new bool();
|
---|
| 760 | bool isdescending = new bool();
|
---|
| 761 |
|
---|
| 762 |
|
---|
| 763 | //
|
---|
| 764 | // Test for already sorted set
|
---|
| 765 | //
|
---|
| 766 | isascending = true;
|
---|
| 767 | isdescending = true;
|
---|
| 768 | for(i=1; i<=n-1; i++)
|
---|
| 769 | {
|
---|
| 770 | isascending = isascending & (double)(x[i])>(double)(x[i-1]);
|
---|
| 771 | isdescending = isdescending & (double)(x[i])<(double)(x[i-1]);
|
---|
| 772 | }
|
---|
| 773 | if( isascending )
|
---|
| 774 | {
|
---|
| 775 | return;
|
---|
| 776 | }
|
---|
| 777 | if( isdescending )
|
---|
| 778 | {
|
---|
| 779 | for(i=0; i<=n-1; i++)
|
---|
| 780 | {
|
---|
| 781 | j = n-1-i;
|
---|
| 782 | if( j<=i )
|
---|
| 783 | {
|
---|
| 784 | break;
|
---|
| 785 | }
|
---|
| 786 | tmp = x[i];
|
---|
| 787 | x[i] = x[j];
|
---|
| 788 | x[j] = tmp;
|
---|
| 789 | tmp = y[i];
|
---|
| 790 | y[i] = y[j];
|
---|
| 791 | y[j] = tmp;
|
---|
| 792 | }
|
---|
| 793 | return;
|
---|
| 794 | }
|
---|
| 795 |
|
---|
| 796 | //
|
---|
| 797 | // Special case: N=1
|
---|
| 798 | //
|
---|
| 799 | if( n==1 )
|
---|
| 800 | {
|
---|
| 801 | return;
|
---|
| 802 | }
|
---|
| 803 |
|
---|
| 804 | //
|
---|
| 805 | // General case
|
---|
| 806 | //
|
---|
| 807 | i = 2;
|
---|
| 808 | do
|
---|
| 809 | {
|
---|
| 810 | t = i;
|
---|
| 811 | while( t!=1 )
|
---|
| 812 | {
|
---|
| 813 | k = t/2;
|
---|
| 814 | if( (double)(x[k-1])>=(double)(x[t-1]) )
|
---|
| 815 | {
|
---|
| 816 | t = 1;
|
---|
| 817 | }
|
---|
| 818 | else
|
---|
| 819 | {
|
---|
| 820 | tmp = x[k-1];
|
---|
| 821 | x[k-1] = x[t-1];
|
---|
| 822 | x[t-1] = tmp;
|
---|
| 823 | tmp = y[k-1];
|
---|
| 824 | y[k-1] = y[t-1];
|
---|
| 825 | y[t-1] = tmp;
|
---|
| 826 | t = k;
|
---|
| 827 | }
|
---|
| 828 | }
|
---|
| 829 | i = i+1;
|
---|
| 830 | }
|
---|
| 831 | while( i<=n );
|
---|
| 832 | i = n-1;
|
---|
| 833 | do
|
---|
| 834 | {
|
---|
| 835 | tmp = x[i];
|
---|
| 836 | x[i] = x[0];
|
---|
| 837 | x[0] = tmp;
|
---|
| 838 | tmp = y[i];
|
---|
| 839 | y[i] = y[0];
|
---|
| 840 | y[0] = tmp;
|
---|
| 841 | t = 1;
|
---|
| 842 | while( t!=0 )
|
---|
| 843 | {
|
---|
| 844 | k = 2*t;
|
---|
| 845 | if( k>i )
|
---|
| 846 | {
|
---|
| 847 | t = 0;
|
---|
| 848 | }
|
---|
| 849 | else
|
---|
| 850 | {
|
---|
| 851 | if( k<i )
|
---|
| 852 | {
|
---|
| 853 | if( (double)(x[k])>(double)(x[k-1]) )
|
---|
| 854 | {
|
---|
| 855 | k = k+1;
|
---|
| 856 | }
|
---|
| 857 | }
|
---|
| 858 | if( (double)(x[t-1])>=(double)(x[k-1]) )
|
---|
| 859 | {
|
---|
| 860 | t = 0;
|
---|
| 861 | }
|
---|
| 862 | else
|
---|
| 863 | {
|
---|
| 864 | tmp = x[k-1];
|
---|
| 865 | x[k-1] = x[t-1];
|
---|
| 866 | x[t-1] = tmp;
|
---|
| 867 | tmp = y[k-1];
|
---|
| 868 | y[k-1] = y[t-1];
|
---|
| 869 | y[t-1] = tmp;
|
---|
| 870 | t = k;
|
---|
| 871 | }
|
---|
| 872 | }
|
---|
| 873 | }
|
---|
| 874 | i = i-1;
|
---|
| 875 | }
|
---|
| 876 | while( i>=1 );
|
---|
| 877 | }
|
---|
| 878 |
|
---|
| 879 |
|
---|
| 880 | private static void heapsortdpoints(ref double[] x,
|
---|
| 881 | ref double[] y,
|
---|
| 882 | ref double[] d,
|
---|
| 883 | int n)
|
---|
| 884 | {
|
---|
| 885 | int i = 0;
|
---|
| 886 | int j = 0;
|
---|
| 887 | int k = 0;
|
---|
| 888 | int t = 0;
|
---|
| 889 | double tmp = 0;
|
---|
| 890 | bool isascending = new bool();
|
---|
| 891 | bool isdescending = new bool();
|
---|
| 892 |
|
---|
| 893 |
|
---|
| 894 | //
|
---|
| 895 | // Test for already sorted set
|
---|
| 896 | //
|
---|
| 897 | isascending = true;
|
---|
| 898 | isdescending = true;
|
---|
| 899 | for(i=1; i<=n-1; i++)
|
---|
| 900 | {
|
---|
| 901 | isascending = isascending & (double)(x[i])>(double)(x[i-1]);
|
---|
| 902 | isdescending = isdescending & (double)(x[i])<(double)(x[i-1]);
|
---|
| 903 | }
|
---|
| 904 | if( isascending )
|
---|
| 905 | {
|
---|
| 906 | return;
|
---|
| 907 | }
|
---|
| 908 | if( isdescending )
|
---|
| 909 | {
|
---|
| 910 | for(i=0; i<=n-1; i++)
|
---|
| 911 | {
|
---|
| 912 | j = n-1-i;
|
---|
| 913 | if( j<=i )
|
---|
| 914 | {
|
---|
| 915 | break;
|
---|
| 916 | }
|
---|
| 917 | tmp = x[i];
|
---|
| 918 | x[i] = x[j];
|
---|
| 919 | x[j] = tmp;
|
---|
| 920 | tmp = y[i];
|
---|
| 921 | y[i] = y[j];
|
---|
| 922 | y[j] = tmp;
|
---|
| 923 | tmp = d[i];
|
---|
| 924 | d[i] = d[j];
|
---|
| 925 | d[j] = tmp;
|
---|
| 926 | }
|
---|
| 927 | return;
|
---|
| 928 | }
|
---|
| 929 |
|
---|
| 930 | //
|
---|
| 931 | // Special case: N=1
|
---|
| 932 | //
|
---|
| 933 | if( n==1 )
|
---|
| 934 | {
|
---|
| 935 | return;
|
---|
| 936 | }
|
---|
| 937 |
|
---|
| 938 | //
|
---|
| 939 | // General case
|
---|
| 940 | //
|
---|
| 941 | i = 2;
|
---|
| 942 | do
|
---|
| 943 | {
|
---|
| 944 | t = i;
|
---|
| 945 | while( t!=1 )
|
---|
| 946 | {
|
---|
| 947 | k = t/2;
|
---|
| 948 | if( (double)(x[k-1])>=(double)(x[t-1]) )
|
---|
| 949 | {
|
---|
| 950 | t = 1;
|
---|
| 951 | }
|
---|
| 952 | else
|
---|
| 953 | {
|
---|
| 954 | tmp = x[k-1];
|
---|
| 955 | x[k-1] = x[t-1];
|
---|
| 956 | x[t-1] = tmp;
|
---|
| 957 | tmp = y[k-1];
|
---|
| 958 | y[k-1] = y[t-1];
|
---|
| 959 | y[t-1] = tmp;
|
---|
| 960 | tmp = d[k-1];
|
---|
| 961 | d[k-1] = d[t-1];
|
---|
| 962 | d[t-1] = tmp;
|
---|
| 963 | t = k;
|
---|
| 964 | }
|
---|
| 965 | }
|
---|
| 966 | i = i+1;
|
---|
| 967 | }
|
---|
| 968 | while( i<=n );
|
---|
| 969 | i = n-1;
|
---|
| 970 | do
|
---|
| 971 | {
|
---|
| 972 | tmp = x[i];
|
---|
| 973 | x[i] = x[0];
|
---|
| 974 | x[0] = tmp;
|
---|
| 975 | tmp = y[i];
|
---|
| 976 | y[i] = y[0];
|
---|
| 977 | y[0] = tmp;
|
---|
| 978 | tmp = d[i];
|
---|
| 979 | d[i] = d[0];
|
---|
| 980 | d[0] = tmp;
|
---|
| 981 | t = 1;
|
---|
| 982 | while( t!=0 )
|
---|
| 983 | {
|
---|
| 984 | k = 2*t;
|
---|
| 985 | if( k>i )
|
---|
| 986 | {
|
---|
| 987 | t = 0;
|
---|
| 988 | }
|
---|
| 989 | else
|
---|
| 990 | {
|
---|
| 991 | if( k<i )
|
---|
| 992 | {
|
---|
| 993 | if( (double)(x[k])>(double)(x[k-1]) )
|
---|
| 994 | {
|
---|
| 995 | k = k+1;
|
---|
| 996 | }
|
---|
| 997 | }
|
---|
| 998 | if( (double)(x[t-1])>=(double)(x[k-1]) )
|
---|
| 999 | {
|
---|
| 1000 | t = 0;
|
---|
| 1001 | }
|
---|
| 1002 | else
|
---|
| 1003 | {
|
---|
| 1004 | tmp = x[k-1];
|
---|
| 1005 | x[k-1] = x[t-1];
|
---|
| 1006 | x[t-1] = tmp;
|
---|
| 1007 | tmp = y[k-1];
|
---|
| 1008 | y[k-1] = y[t-1];
|
---|
| 1009 | y[t-1] = tmp;
|
---|
| 1010 | tmp = d[k-1];
|
---|
| 1011 | d[k-1] = d[t-1];
|
---|
| 1012 | d[t-1] = tmp;
|
---|
| 1013 | t = k;
|
---|
| 1014 | }
|
---|
| 1015 | }
|
---|
| 1016 | }
|
---|
| 1017 | i = i-1;
|
---|
| 1018 | }
|
---|
| 1019 | while( i>=1 );
|
---|
| 1020 | }
|
---|
| 1021 |
|
---|
| 1022 |
|
---|
| 1023 | private static void solvetridiagonal(double[] a,
|
---|
| 1024 | double[] b,
|
---|
| 1025 | double[] c,
|
---|
| 1026 | double[] d,
|
---|
| 1027 | int n,
|
---|
| 1028 | ref double[] x)
|
---|
| 1029 | {
|
---|
| 1030 | int k = 0;
|
---|
| 1031 | double t = 0;
|
---|
| 1032 |
|
---|
| 1033 | a = (double[])a.Clone();
|
---|
| 1034 | b = (double[])b.Clone();
|
---|
| 1035 | c = (double[])c.Clone();
|
---|
| 1036 | d = (double[])d.Clone();
|
---|
| 1037 |
|
---|
| 1038 | x = new double[n-1+1];
|
---|
| 1039 | a[0] = 0;
|
---|
| 1040 | c[n-1] = 0;
|
---|
| 1041 | for(k=1; k<=n-1; k++)
|
---|
| 1042 | {
|
---|
| 1043 | t = a[k]/b[k-1];
|
---|
| 1044 | b[k] = b[k]-t*c[k-1];
|
---|
| 1045 | d[k] = d[k]-t*d[k-1];
|
---|
| 1046 | }
|
---|
| 1047 | x[n-1] = d[n-1]/b[n-1];
|
---|
| 1048 | for(k=n-2; k>=0; k--)
|
---|
| 1049 | {
|
---|
| 1050 | x[k] = (d[k]-c[k]*x[k+1])/b[k];
|
---|
| 1051 | }
|
---|
| 1052 | }
|
---|
| 1053 |
|
---|
| 1054 |
|
---|
| 1055 | private static double diffthreepoint(double t,
|
---|
| 1056 | double x0,
|
---|
| 1057 | double f0,
|
---|
| 1058 | double x1,
|
---|
| 1059 | double f1,
|
---|
| 1060 | double x2,
|
---|
| 1061 | double f2)
|
---|
| 1062 | {
|
---|
| 1063 | double result = 0;
|
---|
| 1064 | double a = 0;
|
---|
| 1065 | double b = 0;
|
---|
| 1066 |
|
---|
| 1067 | t = t-x0;
|
---|
| 1068 | x1 = x1-x0;
|
---|
| 1069 | x2 = x2-x0;
|
---|
| 1070 | a = (f2-f0-x2/x1*(f1-f0))/(AP.Math.Sqr(x2)-x1*x2);
|
---|
| 1071 | b = (f1-f0-a*AP.Math.Sqr(x1))/x1;
|
---|
| 1072 | result = 2*a*t+b;
|
---|
| 1073 | return result;
|
---|
| 1074 | }
|
---|
| 1075 | }
|
---|
| 1076 | }
|
---|