C.rar_newmark_sense7bh

#include "stdlib.h" #include "math.h" #include "stdio.h" #if gaus.c #define gaus.c int gaus(a, b, n) int n; double a[], b[]; { int *js, l, k, i, j, is, p, q; double d, t; js = malloc(n*sizeof(int)); l = 1; for (k = 0; k <= n - 2; k++) { d = 0.0; for (i = k; i <= n - 1; i++) for (j = k; j <= n - 1; j++) { t = fabs(a[i*n + j]); if (t>d) { d = t; js[k] = j; is = i; } } if (d + 1.0 == 1.0) l = 0; else { if (js[k] != k) for (i = 0; i <= n - 1; i++) { p = i*n + k; q = i*n + js[k]; t = a[p]; a[p] = a[q]; a[q] = t; } if (is != k) { for (j = k; j <= n - 1; j++) { p = k*n + j; q = is*n + j; t = a[p]; a[p] = a[q]; a[q] = t; } t = b[k]; b[k] = b[is]; b[is] = t; } } if (l == 0) { free(js); printf("fail\n"); return(0); } d = a[k*n + k]; for (j = k + 1; j <= n - 1; j++) { p = k*n + j; a[p] = a[p] / d; } b[k] = b[k] / d; for (i = k + 1; i <= n - 1; i++) { for (j = k + 1; j <= n - 1; j++) { p = i*n + j; a[p] = a[p] - a[i*n + k] * a[k*n + j]; } b[i] = b[i] - a[i*n + k] * b[k]; } } d = a[(n - 1)*n + n - 1]; if (fabs(d) + 1.0 == 1.0) { free(js); printf("fail\n"); return(0); } b[n - 1] = b[n - 1] / d; for (i = n - 2; i >= 0; i--) { t = 0.0; for (j = i + 1; j <= n - 1; j++) t = t + a[i*n + j] * b[j]; b[i] = b[i] - t; } js[n - 1] = n - 1; for (k = n - 1; k >= 0; k--) if (js[k] != k) { t = b[k]; b[k] = b[js[k]]; b[js[k]] = t; } free(js); return(1); } #endif