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19025d77ad
Reorganized. Created a new top level include directory that will hold all of Trick's header files. Moved all of the Trick headers to this directory. Created a libexec directory that holds all of the executables that users don't need to execute directly. Changed all of the executables remaining in bin to start with "trick-". In the sim_services directories changed all source files to find the Trick headers in their new location. Since all of the include files are gone in sim_services, removed the src directories as well, moving all of the source files up a level. Moved the makefiles, docs, man, and other architecture independent files into a top level share directory. Renamed lib_${TRICK_HOST_CPU} to lib64 or lib depending on the platform we're currently on.
refs #63
86 lines
2.7 KiB
C
86 lines
2.7 KiB
C
/*
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PURPOSE: (Eigenvalues and eigenvectors of symmetric matrix)
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REFERENCE: ((Numerical Recipes [FORTRAN]) (QL transformation with origin shifts))
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ASSUMPTIONS AND LIMITATIONS: ((Square matrix))
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PROGRAMMERS: (((M Schira) (MDSS) (Jan 1994) (v1.0) (Init Release))) */
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#include <stdio.h>
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#include <stdlib.h>
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#include <math.h>
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#include "trick/trick_math.h"
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void eigen_ql(double *d, /* Inout: input diagonal elements, output eigenvalues */
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double *e, /* In: off diagonal elements */
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int n, /* In: array size */
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double **z)
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{ /* Out: eigenvectors */
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int i, k, l, m, iter;
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double f, g, r, s, c, p, dd, b;
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if (n > 1) {
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for (i = 1; i < n; i++)
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e[i - 1] = e[i];
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e[n - 1] = 0.0;
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for (l = 0; l < n; l++) {
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iter = 0;
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label_1:
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for (m = l; m < n - 1; m++) {
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dd = fabs(d[m]) + fabs(d[m + 1]);
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if (fabs(e[m]) + dd == dd)
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goto label_2;
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}
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m = n - 1;
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label_2:
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if (m != l) {
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if (iter == 30) {
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fprintf(stderr, "30 iterations in tqli \n");
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exit(0);
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}
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iter++;
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g = (d[l + 1] - d[l]) / (2.0 * e[l]);
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r = sqrt(g * g + 1.0);
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g = d[m] - d[l] + e[l] / (g + copysign(r, g));
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s = 1.0;
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c = 1.0;
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p = 0.0;
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for (i = m - 1; i >= l; i--) {
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f = s * e[i];
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b = c * e[i];
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if (fabs(f) >= fabs(g)) {
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c = g / f;
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r = sqrt(c * c + 1.0);
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e[i + 1] = f * r;
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s = 1.0 / r;
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c = c * s;
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} else {
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s = f / g;
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r = sqrt(s * s + 1.0);
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e[i + 1] = g * r;
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c = 1.0 / r;
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s = s * c;
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}
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g = d[i + 1] - p;
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r = (d[i] - g) * s + 2.0 * c * b;
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p = s * r;
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d[i + 1] = g + p;
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g = c * r - b;
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for (k = 0; k < n; k++) {
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f = z[k][i + 1];
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z[k][i + 1] = s * z[k][i] + c * f;
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z[k][i] = c * z[k][i] - s * f;
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}
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}
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d[l] -= p;
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e[l] = g;
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e[m] = 0.0;
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goto label_1;
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}
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}
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}
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return;
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}
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