//二次元離散フーリエ変換 #define alloc_error_check(p) { \ if ((p) == NULL) { \ fprintf(stderr, "Allocation Failure!\n"); \ exit(1); \ } \ } //配列の動的確保ルーチン in C int *alloc_1d_int(int n1); void free_1d_int(int *i); double *alloc_1d_double(int n1); void free_1d_double(double *d); int **alloc_2d_int(int n1, int n2); void free_2d_int(int **ii); double **alloc_2d_double(int n1, int n2); void free_2d_double(double **dd); int ***alloc_3d_int(int n1, int n2, int n3); void free_3d_int(int ***iii); double ***alloc_3d_double(int n1, int n2, int n3); void free_3d_double(double ***ddd); //二次元離散フーリエ変換 void cdft2d(int n1, int n2, int isgn, double **a, int *ip, double *w); void makewt(int nw, int *ip, double *w); void bitrv2(int n, int *ip, double *a); void bitrv2col(int n1, int n, int *ip, double **a); void bitrv2row(int n, int n2, int *ip, double **a); void cftbcol(int n1, int n, double **a, double *w); void cftbrow(int n, int n2, double **a, double *w); void cftfcol(int n1, int n, double **a, double *w); void cftfrow(int n, int n2, double **a, double *w); //配列の動的確保ルーチン int *alloc_1d_int(int n1) { int *i; i = (int *) malloc(sizeof(int) * n1); alloc_error_check(i); return i; } void free_1d_int(int *i) { free(i); } double *alloc_1d_double(int n1) { double *d; d = (double *) malloc(sizeof(double) * n1); alloc_error_check(d); return d; } void free_1d_double(double *d) { free(d); } int **alloc_2d_int(int n1, int n2) { int **ii, *i; int j; ii = (int **) malloc(sizeof(int *) * n1); alloc_error_check(ii); i = (int *) malloc(sizeof(int) * n1 * n2); alloc_error_check(i); ii[0] = i; for (j = 1; j < n1; j++) { ii[j] = ii[j - 1] + n2; } return ii; } void free_2d_int(int **ii) { free(ii[0]); free(ii); } double **alloc_2d_double(int n1, int n2) { double **dd, *d; int j; dd = (double **) malloc(sizeof(double *) * n1); alloc_error_check(dd); d = (double *) malloc(sizeof(double) * n1 * n2); alloc_error_check(d); dd[0] = d; for (j = 1; j < n1; j++) { dd[j] = dd[j - 1] + n2; } return dd; } void free_2d_double(double **dd) { free(dd[0]); free(dd); } int ***alloc_3d_int(int n1, int n2, int n3) { int ***iii, **ii, *i; int j; iii = (int ***) malloc(sizeof(int **) * n1); alloc_error_check(iii); ii = (int **) malloc(sizeof(int *) * n1 * n2); alloc_error_check(ii); iii[0] = ii; for (j = 1; j < n1; j++) { iii[j] = iii[j - 1] + n2; } i = (int *) malloc(sizeof(int) * n1 * n2 * n3); alloc_error_check(i); ii[0] = i; for (j = 1; j < n1 * n2; j++) { ii[j] = ii[j - 1] + n3; } return iii; } void free_3d_int(int ***iii) { free(iii[0][0]); free(iii[0]); free(iii); } double ***alloc_3d_double(int n1, int n2, int n3) { double ***ddd, **dd, *d; int j; ddd = (double ***) malloc(sizeof(double **) * n1); alloc_error_check(ddd); dd = (double **) malloc(sizeof(double *) * n1 * n2); alloc_error_check(dd); ddd[0] = dd; for (j = 1; j < n1; j++) { ddd[j] = ddd[j - 1] + n2; } d = (double *) malloc(sizeof(double) * n1 * n2 * n3); alloc_error_check(d); dd[0] = d; for (j = 1; j < n1 * n2; j++) { dd[j] = dd[j - 1] + n3; } return ddd; } void free_3d_double(double ***ddd) { free(ddd[0][0]); free(ddd[0]); free(ddd); } //二次元離散フーリエ変換 void cdft2d(int n1, int n2, int isgn, double **a, int *ip, double *w) { void makewt(int nw, int *ip, double *w); void bitrv2col(int n1, int n, int *ip, double **a); void bitrv2row(int n, int n2, int *ip, double **a); void cftbcol(int n1, int n, double **a, double *w); void cftbrow(int n, int n2, double **a, double *w); void cftfcol(int n1, int n, double **a, double *w); void cftfrow(int n, int n2, double **a, double *w); int n; n = n1 << 1; if (n < n2) { n = n2; } if (n > (ip[0] << 2)) { makewt(n >> 2, ip, w); } if (n2 > 4) { bitrv2col(n1, n2, ip + 2, a); } if (n1 > 2) { bitrv2row(n1, n2, ip + 2, a); } if (isgn < 0) { cftfcol(n1, n2, a, w); cftfrow(n1, n2, a, w); } else { cftbcol(n1, n2, a, w); cftbrow(n1, n2, a, w); } } void makewt(int nw, int *ip, double *w) { void bitrv2(int n, int *ip, double *a); int nwh, j; double delta, x, y; ip[0] = nw; ip[1] = 1; if (nw > 2) { nwh = nw >> 1; delta = atan(1.0) / nwh; w[0] = 1; w[1] = 0; w[nwh] = cos(delta * nwh); w[nwh + 1] = w[nwh]; for (j = 2; j <= nwh - 2; j += 2) { x = cos(delta * j); y = sin(delta * j); w[j] = x; w[j + 1] = y; w[nw - j] = y; w[nw - j + 1] = x; } bitrv2(nw, ip + 2, w); } } void bitrv2(int n, int *ip, double *a) { int j, j1, k, k1, l, m, m2; double xr, xi; ip[0] = 0; l = n; m = 1; while ((m << 2) < l) { l >>= 1; for (j = 0; j <= m - 1; j++) { ip[m + j] = ip[j] + l; } m <<= 1; } if ((m << 2) > l) { for (k = 1; k <= m - 1; k++) { for (j = 0; j <= k - 1; j++) { j1 = (j << 1) + ip[k]; k1 = (k << 1) + ip[j]; xr = a[j1]; xi = a[j1 + 1]; a[j1] = a[k1]; a[j1 + 1] = a[k1 + 1]; a[k1] = xr; a[k1 + 1] = xi; } } } else { m2 = m << 1; for (k = 1; k <= m - 1; k++) { for (j = 0; j <= k - 1; j++) { j1 = (j << 1) + ip[k]; k1 = (k << 1) + ip[j]; xr = a[j1]; xi = a[j1 + 1]; a[j1] = a[k1]; a[j1 + 1] = a[k1 + 1]; a[k1] = xr; a[k1 + 1] = xi; j1 += m2; k1 += m2; xr = a[j1]; xi = a[j1 + 1]; a[j1] = a[k1]; a[j1 + 1] = a[k1 + 1]; a[k1] = xr; a[k1 + 1] = xi; } } } } void bitrv2col(int n1, int n, int *ip, double **a) { int i, j, j1, k, k1, l, m, m2; double xr, xi; ip[0] = 0; l = n; m = 1; while ((m << 2) < l) { l >>= 1; for (j = 0; j <= m - 1; j++) { ip[m + j] = ip[j] + l; } m <<= 1; } if ((m << 2) > l) { for (i = 0; i <= n1 - 1; i++) { for (k = 1; k <= m - 1; k++) { for (j = 0; j <= k - 1; j++) { j1 = (j << 1) + ip[k]; k1 = (k << 1) + ip[j]; xr = a[i][j1]; xi = a[i][j1 + 1]; a[i][j1] = a[i][k1]; a[i][j1 + 1] = a[i][k1 + 1]; a[i][k1] = xr; a[i][k1 + 1] = xi; } } } } else { m2 = m << 1; for (i = 0; i <= n1 - 1; i++) { for (k = 1; k <= m - 1; k++) { for (j = 0; j <= k - 1; j++) { j1 = (j << 1) + ip[k]; k1 = (k << 1) + ip[j]; xr = a[i][j1]; xi = a[i][j1 + 1]; a[i][j1] = a[i][k1]; a[i][j1 + 1] = a[i][k1 + 1]; a[i][k1] = xr; a[i][k1 + 1] = xi; j1 += m2; k1 += m2; xr = a[i][j1]; xi = a[i][j1 + 1]; a[i][j1] = a[i][k1]; a[i][j1 + 1] = a[i][k1 + 1]; a[i][k1] = xr; a[i][k1 + 1] = xi; } } } } } void bitrv2row(int n, int n2, int *ip, double **a) { int i, j, j1, k, k1, l, m; double xr, xi; ip[0] = 0; l = n; m = 1; while ((m << 1) < l) { l >>= 1; for (j = 0; j <= m - 1; j++) { ip[m + j] = ip[j] + l; } m <<= 1; } if ((m << 1) > l) { for (k = 1; k <= m - 1; k++) { for (j = 0; j <= k - 1; j++) { j1 = j + ip[k]; k1 = k + ip[j]; for (i = 0; i <= n2 - 2; i += 2) { xr = a[j1][i]; xi = a[j1][i + 1]; a[j1][i] = a[k1][i]; a[j1][i + 1] = a[k1][i + 1]; a[k1][i] = xr; a[k1][i + 1] = xi; } } } } else { for (k = 1; k <= m - 1; k++) { for (j = 0; j <= k - 1; j++) { j1 = j + ip[k]; k1 = k + ip[j]; for (i = 0; i <= n2 - 2; i += 2) { xr = a[j1][i]; xi = a[j1][i + 1]; a[j1][i] = a[k1][i]; a[j1][i + 1] = a[k1][i + 1]; a[k1][i] = xr; a[k1][i + 1] = xi; } j1 += m; k1 += m; for (i = 0; i <= n2 - 2; i += 2) { xr = a[j1][i]; xi = a[j1][i + 1]; a[j1][i] = a[k1][i]; a[j1][i + 1] = a[k1][i + 1]; a[k1][i] = xr; a[k1][i + 1] = xi; } } } } } void cftbcol(int n1, int n, double **a, double *w) { int i, j, j1, j2, j3, k, k1, ks, l, m; double wk1r, wk1i, wk2r, wk2i, wk3r, wk3i; double x0r, x0i, x1r, x1i, x2r, x2i, x3r, x3i; for (i = 0; i <= n1 - 1; i++) { l = 2; while ((l << 1) < n) { m = l << 2; for (j = 0; j <= l - 2; j += 2) { j1 = j + l; j2 = j1 + l; j3 = j2 + l; x0r = a[i][j] + a[i][j1]; x0i = a[i][j + 1] + a[i][j1 + 1]; x1r = a[i][j] - a[i][j1]; x1i = a[i][j + 1] - a[i][j1 + 1]; x2r = a[i][j2] + a[i][j3]; x2i = a[i][j2 + 1] + a[i][j3 + 1]; x3r = a[i][j2] - a[i][j3]; x3i = a[i][j2 + 1] - a[i][j3 + 1]; a[i][j] = x0r + x2r; a[i][j + 1] = x0i + x2i; a[i][j2] = x0r - x2r; a[i][j2 + 1] = x0i - x2i; a[i][j1] = x1r - x3i; a[i][j1 + 1] = x1i + x3r; a[i][j3] = x1r + x3i; a[i][j3 + 1] = x1i - x3r; } if (m < n) { wk1r = w[2]; for (j = m; j <= l + m - 2; j += 2) { j1 = j + l; j2 = j1 + l; j3 = j2 + l; x0r = a[i][j] + a[i][j1]; x0i = a[i][j + 1] + a[i][j1 + 1]; x1r = a[i][j] - a[i][j1]; x1i = a[i][j + 1] - a[i][j1 + 1]; x2r = a[i][j2] + a[i][j3]; x2i = a[i][j2 + 1] + a[i][j3 + 1]; x3r = a[i][j2] - a[i][j3]; x3i = a[i][j2 + 1] - a[i][j3 + 1]; a[i][j] = x0r + x2r; a[i][j + 1] = x0i + x2i; a[i][j2] = x2i - x0i; a[i][j2 + 1] = x0r - x2r; x0r = x1r - x3i; x0i = x1i + x3r; a[i][j1] = wk1r * (x0r - x0i); a[i][j1 + 1] = wk1r * (x0r + x0i); x0r = x3i + x1r; x0i = x3r - x1i; a[i][j3] = wk1r * (x0i - x0r); a[i][j3 + 1] = wk1r * (x0i + x0r); } k1 = 1; ks = -1; for (k = (m << 1); k <= n - m; k += m) { k1++; ks = -ks; wk1r = w[k1 << 1]; wk1i = w[(k1 << 1) + 1]; wk2r = ks * w[k1]; wk2i = w[k1 + ks]; wk3r = wk1r - 2 * wk2i * wk1i; wk3i = 2 * wk2i * wk1r - wk1i; for (j = k; j <= l + k - 2; j += 2) { j1 = j + l; j2 = j1 + l; j3 = j2 + l; x0r = a[i][j] + a[i][j1]; x0i = a[i][j + 1] + a[i][j1 + 1]; x1r = a[i][j] - a[i][j1]; x1i = a[i][j + 1] - a[i][j1 + 1]; x2r = a[i][j2] + a[i][j3]; x2i = a[i][j2 + 1] + a[i][j3 + 1]; x3r = a[i][j2] - a[i][j3]; x3i = a[i][j2 + 1] - a[i][j3 + 1]; a[i][j] = x0r + x2r; a[i][j + 1] = x0i + x2i; x0r -= x2r; x0i -= x2i; a[i][j2] = wk2r * x0r - wk2i * x0i; a[i][j2 + 1] = wk2r * x0i + wk2i * x0r; x0r = x1r - x3i; x0i = x1i + x3r; a[i][j1] = wk1r * x0r - wk1i * x0i; a[i][j1 + 1] = wk1r * x0i + wk1i * x0r; x0r = x1r + x3i; x0i = x1i - x3r; a[i][j3] = wk3r * x0r - wk3i * x0i; a[i][j3 + 1] = wk3r * x0i + wk3i * x0r; } } } l = m; } if (l < n) { for (j = 0; j <= l - 2; j += 2) { j1 = j + l; x0r = a[i][j] - a[i][j1]; x0i = a[i][j + 1] - a[i][j1 + 1]; a[i][j] += a[i][j1]; a[i][j + 1] += a[i][j1 + 1]; a[i][j1] = x0r; a[i][j1 + 1] = x0i; } } } } void cftbrow(int n, int n2, double **a, double *w) { int i, j, j1, j2, j3, k, k1, ks, l, m; double wk1r, wk1i, wk2r, wk2i, wk3r, wk3i; double x0r, x0i, x1r, x1i, x2r, x2i, x3r, x3i; l = 1; while ((l << 1) < n) { m = l << 2; for (j = 0; j <= l - 1; j++) { j1 = j + l; j2 = j1 + l; j3 = j2 + l; for (i = 0; i <= n2 - 2; i += 2) { x0r = a[j][i] + a[j1][i]; x0i = a[j][i + 1] + a[j1][i + 1]; x1r = a[j][i] - a[j1][i]; x1i = a[j][i + 1] - a[j1][i + 1]; x2r = a[j2][i] + a[j3][i]; x2i = a[j2][i + 1] + a[j3][i + 1]; x3r = a[j2][i] - a[j3][i]; x3i = a[j2][i + 1] - a[j3][i + 1]; a[j][i] = x0r + x2r; a[j][i + 1] = x0i + x2i; a[j2][i] = x0r - x2r; a[j2][i + 1] = x0i - x2i; a[j1][i] = x1r - x3i; a[j1][i + 1] = x1i + x3r; a[j3][i] = x1r + x3i; a[j3][i + 1] = x1i - x3r; } } if (m < n) { wk1r = w[2]; for (j = m; j <= l + m - 1; j++) { j1 = j + l; j2 = j1 + l; j3 = j2 + l; for (i = 0; i <= n2 - 2; i += 2) { x0r = a[j][i] + a[j1][i]; x0i = a[j][i + 1] + a[j1][i + 1]; x1r = a[j][i] - a[j1][i]; x1i = a[j][i + 1] - a[j1][i + 1]; x2r = a[j2][i] + a[j3][i]; x2i = a[j2][i + 1] + a[j3][i + 1]; x3r = a[j2][i] - a[j3][i]; x3i = a[j2][i + 1] - a[j3][i + 1]; a[j][i] = x0r + x2r; a[j][i + 1] = x0i + x2i; a[j2][i] = x2i - x0i; a[j2][i + 1] = x0r - x2r; x0r = x1r - x3i; x0i = x1i + x3r; a[j1][i] = wk1r * (x0r - x0i); a[j1][i + 1] = wk1r * (x0r + x0i); x0r = x3i + x1r; x0i = x3r - x1i; a[j3][i] = wk1r * (x0i - x0r); a[j3][i + 1] = wk1r * (x0i + x0r); } } k1 = 1; ks = -1; for (k = (m << 1); k <= n - m; k += m) { k1++; ks = -ks; wk1r = w[k1 << 1]; wk1i = w[(k1 << 1) + 1]; wk2r = ks * w[k1]; wk2i = w[k1 + ks]; wk3r = wk1r - 2 * wk2i * wk1i; wk3i = 2 * wk2i * wk1r - wk1i; for (j = k; j <= l + k - 1; j++) { j1 = j + l; j2 = j1 + l; j3 = j2 + l; for (i = 0; i <= n2 - 2; i += 2) { x0r = a[j][i] + a[j1][i]; x0i = a[j][i + 1] + a[j1][i + 1]; x1r = a[j][i] - a[j1][i]; x1i = a[j][i + 1] - a[j1][i + 1]; x2r = a[j2][i] + a[j3][i]; x2i = a[j2][i + 1] + a[j3][i + 1]; x3r = a[j2][i] - a[j3][i]; x3i = a[j2][i + 1] - a[j3][i + 1]; a[j][i] = x0r + x2r; a[j][i + 1] = x0i + x2i; x0r -= x2r; x0i -= x2i; a[j2][i] = wk2r * x0r - wk2i * x0i; a[j2][i + 1] = wk2r * x0i + wk2i * x0r; x0r = x1r - x3i; x0i = x1i + x3r; a[j1][i] = wk1r * x0r - wk1i * x0i; a[j1][i + 1] = wk1r * x0i + wk1i * x0r; x0r = x1r + x3i; x0i = x1i - x3r; a[j3][i] = wk3r * x0r - wk3i * x0i; a[j3][i + 1] = wk3r * x0i + wk3i * x0r; } } } } l = m; } if (l < n) { for (j = 0; j <= l - 1; j++) { j1 = j + l; for (i = 0; i <= n2 - 2; i += 2) { x0r = a[j][i] - a[j1][i]; x0i = a[j][i + 1] - a[j1][i + 1]; a[j][i] += a[j1][i]; a[j][i + 1] += a[j1][i + 1]; a[j1][i] = x0r; a[j1][i + 1] = x0i; } } } } void cftfcol(int n1, int n, double **a, double *w) { int i, j, j1, j2, j3, k, k1, ks, l, m; double wk1r, wk1i, wk2r, wk2i, wk3r, wk3i; double x0r, x0i, x1r, x1i, x2r, x2i, x3r, x3i; for (i = 0; i <= n1 - 1; i++) { l = 2; while ((l << 1) < n) { m = l << 2; for (j = 0; j <= l - 2; j += 2) { j1 = j + l; j2 = j1 + l; j3 = j2 + l; x0r = a[i][j] + a[i][j1]; x0i = a[i][j + 1] + a[i][j1 + 1]; x1r = a[i][j] - a[i][j1]; x1i = a[i][j + 1] - a[i][j1 + 1]; x2r = a[i][j2] + a[i][j3]; x2i = a[i][j2 + 1] + a[i][j3 + 1]; x3r = a[i][j2] - a[i][j3]; x3i = a[i][j2 + 1] - a[i][j3 + 1]; a[i][j] = x0r + x2r; a[i][j + 1] = x0i + x2i; a[i][j2] = x0r - x2r; a[i][j2 + 1] = x0i - x2i; a[i][j1] = x1r + x3i; a[i][j1 + 1] = x1i - x3r; a[i][j3] = x1r - x3i; a[i][j3 + 1] = x1i + x3r; } if (m < n) { wk1r = w[2]; for (j = m; j <= l + m - 2; j += 2) { j1 = j + l; j2 = j1 + l; j3 = j2 + l; x0r = a[i][j] + a[i][j1]; x0i = a[i][j + 1] + a[i][j1 + 1]; x1r = a[i][j] - a[i][j1]; x1i = a[i][j + 1] - a[i][j1 + 1]; x2r = a[i][j2] + a[i][j3]; x2i = a[i][j2 + 1] + a[i][j3 + 1]; x3r = a[i][j2] - a[i][j3]; x3i = a[i][j2 + 1] - a[i][j3 + 1]; a[i][j] = x0r + x2r; a[i][j + 1] = x0i + x2i; a[i][j2] = x0i - x2i; a[i][j2 + 1] = x2r - x0r; x0r = x1r + x3i; x0i = x1i - x3r; a[i][j1] = wk1r * (x0i + x0r); a[i][j1 + 1] = wk1r * (x0i - x0r); x0r = x3i - x1r; x0i = x3r + x1i; a[i][j3] = wk1r * (x0r + x0i); a[i][j3 + 1] = wk1r * (x0r - x0i); } k1 = 1; ks = -1; for (k = (m << 1); k <= n - m; k += m) { k1++; ks = -ks; wk1r = w[k1 << 1]; wk1i = w[(k1 << 1) + 1]; wk2r = ks * w[k1]; wk2i = w[k1 + ks]; wk3r = wk1r - 2 * wk2i * wk1i; wk3i = 2 * wk2i * wk1r - wk1i; for (j = k; j <= l + k - 2; j += 2) { j1 = j + l; j2 = j1 + l; j3 = j2 + l; x0r = a[i][j] + a[i][j1]; x0i = a[i][j + 1] + a[i][j1 + 1]; x1r = a[i][j] - a[i][j1]; x1i = a[i][j + 1] - a[i][j1 + 1]; x2r = a[i][j2] + a[i][j3]; x2i = a[i][j2 + 1] + a[i][j3 + 1]; x3r = a[i][j2] - a[i][j3]; x3i = a[i][j2 + 1] - a[i][j3 + 1]; a[i][j] = x0r + x2r; a[i][j + 1] = x0i + x2i; x0r -= x2r; x0i -= x2i; a[i][j2] = wk2r * x0r + wk2i * x0i; a[i][j2 + 1] = wk2r * x0i - wk2i * x0r; x0r = x1r + x3i; x0i = x1i - x3r; a[i][j1] = wk1r * x0r + wk1i * x0i; a[i][j1 + 1] = wk1r * x0i - wk1i * x0r; x0r = x1r - x3i; x0i = x1i + x3r; a[i][j3] = wk3r * x0r + wk3i * x0i; a[i][j3 + 1] = wk3r * x0i - wk3i * x0r; } } } l = m; } if (l < n) { for (j = 0; j <= l - 2; j += 2) { j1 = j + l; x0r = a[i][j] - a[i][j1]; x0i = a[i][j + 1] - a[i][j1 + 1]; a[i][j] += a[i][j1]; a[i][j + 1] += a[i][j1 + 1]; a[i][j1] = x0r; a[i][j1 + 1] = x0i; } } } } void cftfrow(int n, int n2, double **a, double *w) { int i, j, j1, j2, j3, k, k1, ks, l, m; double wk1r, wk1i, wk2r, wk2i, wk3r, wk3i; double x0r, x0i, x1r, x1i, x2r, x2i, x3r, x3i; l = 1; while ((l << 1) < n) { m = l << 2; for (j = 0; j <= l - 1; j++) { j1 = j + l; j2 = j1 + l; j3 = j2 + l; for (i = 0; i <= n2 - 2; i += 2) { x0r = a[j][i] + a[j1][i]; x0i = a[j][i + 1] + a[j1][i + 1]; x1r = a[j][i] - a[j1][i]; x1i = a[j][i + 1] - a[j1][i + 1]; x2r = a[j2][i] + a[j3][i]; x2i = a[j2][i + 1] + a[j3][i + 1]; x3r = a[j2][i] - a[j3][i]; x3i = a[j2][i + 1] - a[j3][i + 1]; a[j][i] = x0r + x2r; a[j][i + 1] = x0i + x2i; a[j2][i] = x0r - x2r; a[j2][i + 1] = x0i - x2i; a[j1][i] = x1r + x3i; a[j1][i + 1] = x1i - x3r; a[j3][i] = x1r - x3i; a[j3][i + 1] = x1i + x3r; } } if (m < n) { wk1r = w[2]; for (j = m; j <= l + m - 1; j++) { j1 = j + l; j2 = j1 + l; j3 = j2 + l; for (i = 0; i <= n2 - 2; i += 2) { x0r = a[j][i] + a[j1][i]; x0i = a[j][i + 1] + a[j1][i + 1]; x1r = a[j][i] - a[j1][i]; x1i = a[j][i + 1] - a[j1][i + 1]; x2r = a[j2][i] + a[j3][i]; x2i = a[j2][i + 1] + a[j3][i + 1]; x3r = a[j2][i] - a[j3][i]; x3i = a[j2][i + 1] - a[j3][i + 1]; a[j][i] = x0r + x2r; a[j][i + 1] = x0i + x2i; a[j2][i] = x0i - x2i; a[j2][i + 1] = x2r - x0r; x0r = x1r + x3i; x0i = x1i - x3r; a[j1][i] = wk1r * (x0i + x0r); a[j1][i + 1] = wk1r * (x0i - x0r); x0r = x3i - x1r; x0i = x3r + x1i; a[j3][i] = wk1r * (x0r + x0i); a[j3][i + 1] = wk1r * (x0r - x0i); } } k1 = 1; ks = -1; for (k = (m << 1); k <= n - m; k += m) { k1++; ks = -ks; wk1r = w[k1 << 1]; wk1i = w[(k1 << 1) + 1]; wk2r = ks * w[k1]; wk2i = w[k1 + ks]; wk3r = wk1r - 2 * wk2i * wk1i; wk3i = 2 * wk2i * wk1r - wk1i; for (j = k; j <= l + k - 1; j++) { j1 = j + l; j2 = j1 + l; j3 = j2 + l; for (i = 0; i <= n2 - 2; i += 2) { x0r = a[j][i] + a[j1][i]; x0i = a[j][i + 1] + a[j1][i + 1]; x1r = a[j][i] - a[j1][i]; x1i = a[j][i + 1] - a[j1][i + 1]; x2r = a[j2][i] + a[j3][i]; x2i = a[j2][i + 1] + a[j3][i + 1]; x3r = a[j2][i] - a[j3][i]; x3i = a[j2][i + 1] - a[j3][i + 1]; a[j][i] = x0r + x2r; a[j][i + 1] = x0i + x2i; x0r -= x2r; x0i -= x2i; a[j2][i] = wk2r * x0r + wk2i * x0i; a[j2][i + 1] = wk2r * x0i - wk2i * x0r; x0r = x1r + x3i; x0i = x1i - x3r; a[j1][i] = wk1r * x0r + wk1i * x0i; a[j1][i + 1] = wk1r * x0i - wk1i * x0r; x0r = x1r - x3i; x0i = x1i + x3r; a[j3][i] = wk3r * x0r + wk3i * x0i; a[j3][i + 1] = wk3r * x0i - wk3i * x0r; } } } } l = m; } if (l < n) { for (j = 0; j <= l - 1; j++) { j1 = j + l; for (i = 0; i <= n2 - 2; i += 2) { x0r = a[j][i] - a[j1][i]; x0i = a[j][i + 1] - a[j1][i + 1]; a[j][i] += a[j1][i]; a[j][i + 1] += a[j1][i + 1]; a[j1][i] = x0r; a[j1][i + 1] = x0i; } } } }