|  | /* | 
|  | Fast Fourier/Cosine/Sine Transform | 
|  | dimension   :one | 
|  | data length :power of 2 | 
|  | decimation  :frequency | 
|  | radix       :split-radix | 
|  | data        :inplace | 
|  | table       :use | 
|  | functions | 
|  | cdft: Complex Discrete Fourier Transform | 
|  | rdft: Real Discrete Fourier Transform | 
|  | ddct: Discrete Cosine Transform | 
|  | ddst: Discrete Sine Transform | 
|  | dfct: Cosine Transform of RDFT (Real Symmetric DFT) | 
|  | dfst: Sine Transform of RDFT (Real Anti-symmetric DFT) | 
|  | function prototypes | 
|  | void cdft(int, int, double *, int *, double *); | 
|  | void rdft(int, int, double *, int *, double *); | 
|  | void ddct(int, int, double *, int *, double *); | 
|  | void ddst(int, int, double *, int *, double *); | 
|  | void dfct(int, double *, double *, int *, double *); | 
|  | void dfst(int, double *, double *, int *, double *); | 
|  | macro definitions | 
|  | USE_CDFT_PTHREADS : default=not defined | 
|  | CDFT_THREADS_BEGIN_N  : must be >= 512, default=8192 | 
|  | CDFT_4THREADS_BEGIN_N : must be >= 512, default=65536 | 
|  | USE_CDFT_WINTHREADS : default=not defined | 
|  | CDFT_THREADS_BEGIN_N  : must be >= 512, default=32768 | 
|  | CDFT_4THREADS_BEGIN_N : must be >= 512, default=524288 | 
|  |  | 
|  |  | 
|  | -------- Complex DFT (Discrete Fourier Transform) -------- | 
|  | [definition] | 
|  | <case1> | 
|  | X[k] = sum_j=0^n-1 x[j]*exp(2*pi*i*j*k/n), 0<=k<n | 
|  | <case2> | 
|  | X[k] = sum_j=0^n-1 x[j]*exp(-2*pi*i*j*k/n), 0<=k<n | 
|  | (notes: sum_j=0^n-1 is a summation from j=0 to n-1) | 
|  | [usage] | 
|  | <case1> | 
|  | ip[0] = 0; // first time only | 
|  | cdft(2*n, 1, a, ip, w); | 
|  | <case2> | 
|  | ip[0] = 0; // first time only | 
|  | cdft(2*n, -1, a, ip, w); | 
|  | [parameters] | 
|  | 2*n            :data length (int) | 
|  | n >= 1, n = power of 2 | 
|  | a[0...2*n-1]   :input/output data (double *) | 
|  | input data | 
|  | a[2*j] = Re(x[j]), | 
|  | a[2*j+1] = Im(x[j]), 0<=j<n | 
|  | output data | 
|  | a[2*k] = Re(X[k]), | 
|  | a[2*k+1] = Im(X[k]), 0<=k<n | 
|  | ip[0...*]      :work area for bit reversal (int *) | 
|  | length of ip >= 2+sqrt(n) | 
|  | strictly, | 
|  | length of ip >= | 
|  | 2+(1<<(int)(log(n+0.5)/log(2))/2). | 
|  | ip[0],ip[1] are pointers of the cos/sin table. | 
|  | w[0...n/2-1]   :cos/sin table (double *) | 
|  | w[],ip[] are initialized if ip[0] == 0. | 
|  | [remark] | 
|  | Inverse of | 
|  | cdft(2*n, -1, a, ip, w); | 
|  | is | 
|  | cdft(2*n, 1, a, ip, w); | 
|  | for (j = 0; j <= 2 * n - 1; j++) { | 
|  | a[j] *= 1.0 / n; | 
|  | } | 
|  | . | 
|  |  | 
|  |  | 
|  | -------- Real DFT / Inverse of Real DFT -------- | 
|  | [definition] | 
|  | <case1> RDFT | 
|  | R[k] = sum_j=0^n-1 a[j]*cos(2*pi*j*k/n), 0<=k<=n/2 | 
|  | I[k] = sum_j=0^n-1 a[j]*sin(2*pi*j*k/n), 0<k<n/2 | 
|  | <case2> IRDFT (excluding scale) | 
|  | a[k] = (R[0] + R[n/2]*cos(pi*k))/2 + | 
|  | sum_j=1^n/2-1 R[j]*cos(2*pi*j*k/n) + | 
|  | sum_j=1^n/2-1 I[j]*sin(2*pi*j*k/n), 0<=k<n | 
|  | [usage] | 
|  | <case1> | 
|  | ip[0] = 0; // first time only | 
|  | rdft(n, 1, a, ip, w); | 
|  | <case2> | 
|  | ip[0] = 0; // first time only | 
|  | rdft(n, -1, a, ip, w); | 
|  | [parameters] | 
|  | n              :data length (int) | 
|  | n >= 2, n = power of 2 | 
|  | a[0...n-1]     :input/output data (double *) | 
|  | <case1> | 
|  | output data | 
|  | a[2*k] = R[k], 0<=k<n/2 | 
|  | a[2*k+1] = I[k], 0<k<n/2 | 
|  | a[1] = R[n/2] | 
|  | <case2> | 
|  | input data | 
|  | a[2*j] = R[j], 0<=j<n/2 | 
|  | a[2*j+1] = I[j], 0<j<n/2 | 
|  | a[1] = R[n/2] | 
|  | ip[0...*]      :work area for bit reversal (int *) | 
|  | length of ip >= 2+sqrt(n/2) | 
|  | strictly, | 
|  | length of ip >= | 
|  | 2+(1<<(int)(log(n/2+0.5)/log(2))/2). | 
|  | ip[0],ip[1] are pointers of the cos/sin table. | 
|  | w[0...n/2-1]   :cos/sin table (double *) | 
|  | w[],ip[] are initialized if ip[0] == 0. | 
|  | [remark] | 
|  | Inverse of | 
|  | rdft(n, 1, a, ip, w); | 
|  | is | 
|  | rdft(n, -1, a, ip, w); | 
|  | for (j = 0; j <= n - 1; j++) { | 
|  | a[j] *= 2.0 / n; | 
|  | } | 
|  | . | 
|  |  | 
|  |  | 
|  | -------- DCT (Discrete Cosine Transform) / Inverse of DCT -------- | 
|  | [definition] | 
|  | <case1> IDCT (excluding scale) | 
|  | C[k] = sum_j=0^n-1 a[j]*cos(pi*j*(k+1/2)/n), 0<=k<n | 
|  | <case2> DCT | 
|  | C[k] = sum_j=0^n-1 a[j]*cos(pi*(j+1/2)*k/n), 0<=k<n | 
|  | [usage] | 
|  | <case1> | 
|  | ip[0] = 0; // first time only | 
|  | ddct(n, 1, a, ip, w); | 
|  | <case2> | 
|  | ip[0] = 0; // first time only | 
|  | ddct(n, -1, a, ip, w); | 
|  | [parameters] | 
|  | n              :data length (int) | 
|  | n >= 2, n = power of 2 | 
|  | a[0...n-1]     :input/output data (double *) | 
|  | output data | 
|  | a[k] = C[k], 0<=k<n | 
|  | ip[0...*]      :work area for bit reversal (int *) | 
|  | length of ip >= 2+sqrt(n/2) | 
|  | strictly, | 
|  | length of ip >= | 
|  | 2+(1<<(int)(log(n/2+0.5)/log(2))/2). | 
|  | ip[0],ip[1] are pointers of the cos/sin table. | 
|  | w[0...n*5/4-1] :cos/sin table (double *) | 
|  | w[],ip[] are initialized if ip[0] == 0. | 
|  | [remark] | 
|  | Inverse of | 
|  | ddct(n, -1, a, ip, w); | 
|  | is | 
|  | a[0] *= 0.5; | 
|  | ddct(n, 1, a, ip, w); | 
|  | for (j = 0; j <= n - 1; j++) { | 
|  | a[j] *= 2.0 / n; | 
|  | } | 
|  | . | 
|  |  | 
|  |  | 
|  | -------- DST (Discrete Sine Transform) / Inverse of DST -------- | 
|  | [definition] | 
|  | <case1> IDST (excluding scale) | 
|  | S[k] = sum_j=1^n A[j]*sin(pi*j*(k+1/2)/n), 0<=k<n | 
|  | <case2> DST | 
|  | S[k] = sum_j=0^n-1 a[j]*sin(pi*(j+1/2)*k/n), 0<k<=n | 
|  | [usage] | 
|  | <case1> | 
|  | ip[0] = 0; // first time only | 
|  | ddst(n, 1, a, ip, w); | 
|  | <case2> | 
|  | ip[0] = 0; // first time only | 
|  | ddst(n, -1, a, ip, w); | 
|  | [parameters] | 
|  | n              :data length (int) | 
|  | n >= 2, n = power of 2 | 
|  | a[0...n-1]     :input/output data (double *) | 
|  | <case1> | 
|  | input data | 
|  | a[j] = A[j], 0<j<n | 
|  | a[0] = A[n] | 
|  | output data | 
|  | a[k] = S[k], 0<=k<n | 
|  | <case2> | 
|  | output data | 
|  | a[k] = S[k], 0<k<n | 
|  | a[0] = S[n] | 
|  | ip[0...*]      :work area for bit reversal (int *) | 
|  | length of ip >= 2+sqrt(n/2) | 
|  | strictly, | 
|  | length of ip >= | 
|  | 2+(1<<(int)(log(n/2+0.5)/log(2))/2). | 
|  | ip[0],ip[1] are pointers of the cos/sin table. | 
|  | w[0...n*5/4-1] :cos/sin table (double *) | 
|  | w[],ip[] are initialized if ip[0] == 0. | 
|  | [remark] | 
|  | Inverse of | 
|  | ddst(n, -1, a, ip, w); | 
|  | is | 
|  | a[0] *= 0.5; | 
|  | ddst(n, 1, a, ip, w); | 
|  | for (j = 0; j <= n - 1; j++) { | 
|  | a[j] *= 2.0 / n; | 
|  | } | 
|  | . | 
|  |  | 
|  |  | 
|  | -------- Cosine Transform of RDFT (Real Symmetric DFT) -------- | 
|  | [definition] | 
|  | C[k] = sum_j=0^n a[j]*cos(pi*j*k/n), 0<=k<=n | 
|  | [usage] | 
|  | ip[0] = 0; // first time only | 
|  | dfct(n, a, t, ip, w); | 
|  | [parameters] | 
|  | n              :data length - 1 (int) | 
|  | n >= 2, n = power of 2 | 
|  | a[0...n]       :input/output data (double *) | 
|  | output data | 
|  | a[k] = C[k], 0<=k<=n | 
|  | t[0...n/2]     :work area (double *) | 
|  | ip[0...*]      :work area for bit reversal (int *) | 
|  | length of ip >= 2+sqrt(n/4) | 
|  | strictly, | 
|  | length of ip >= | 
|  | 2+(1<<(int)(log(n/4+0.5)/log(2))/2). | 
|  | ip[0],ip[1] are pointers of the cos/sin table. | 
|  | w[0...n*5/8-1] :cos/sin table (double *) | 
|  | w[],ip[] are initialized if ip[0] == 0. | 
|  | [remark] | 
|  | Inverse of | 
|  | a[0] *= 0.5; | 
|  | a[n] *= 0.5; | 
|  | dfct(n, a, t, ip, w); | 
|  | is | 
|  | a[0] *= 0.5; | 
|  | a[n] *= 0.5; | 
|  | dfct(n, a, t, ip, w); | 
|  | for (j = 0; j <= n; j++) { | 
|  | a[j] *= 2.0 / n; | 
|  | } | 
|  | . | 
|  |  | 
|  |  | 
|  | -------- Sine Transform of RDFT (Real Anti-symmetric DFT) -------- | 
|  | [definition] | 
|  | S[k] = sum_j=1^n-1 a[j]*sin(pi*j*k/n), 0<k<n | 
|  | [usage] | 
|  | ip[0] = 0; // first time only | 
|  | dfst(n, a, t, ip, w); | 
|  | [parameters] | 
|  | n              :data length + 1 (int) | 
|  | n >= 2, n = power of 2 | 
|  | a[0...n-1]     :input/output data (double *) | 
|  | output data | 
|  | a[k] = S[k], 0<k<n | 
|  | (a[0] is used for work area) | 
|  | t[0...n/2-1]   :work area (double *) | 
|  | ip[0...*]      :work area for bit reversal (int *) | 
|  | length of ip >= 2+sqrt(n/4) | 
|  | strictly, | 
|  | length of ip >= | 
|  | 2+(1<<(int)(log(n/4+0.5)/log(2))/2). | 
|  | ip[0],ip[1] are pointers of the cos/sin table. | 
|  | w[0...n*5/8-1] :cos/sin table (double *) | 
|  | w[],ip[] are initialized if ip[0] == 0. | 
|  | [remark] | 
|  | Inverse of | 
|  | dfst(n, a, t, ip, w); | 
|  | is | 
|  | dfst(n, a, t, ip, w); | 
|  | for (j = 1; j <= n - 1; j++) { | 
|  | a[j] *= 2.0 / n; | 
|  | } | 
|  | . | 
|  |  | 
|  |  | 
|  | Appendix : | 
|  | The cos/sin table is recalculated when the larger table required. | 
|  | w[] and ip[] are compatible with all routines. | 
|  | */ | 
|  |  | 
|  |  | 
|  | void cdft(int n, int isgn, double *a, int *ip, double *w) | 
|  | { | 
|  | void makewt(int nw, int *ip, double *w); | 
|  | void cftfsub(int n, double *a, int *ip, int nw, double *w); | 
|  | void cftbsub(int n, double *a, int *ip, int nw, double *w); | 
|  | int nw; | 
|  |  | 
|  | nw = ip[0]; | 
|  | if (n > (nw << 2)) { | 
|  | nw = n >> 2; | 
|  | makewt(nw, ip, w); | 
|  | } | 
|  | if (isgn >= 0) { | 
|  | cftfsub(n, a, ip, nw, w); | 
|  | } else { | 
|  | cftbsub(n, a, ip, nw, w); | 
|  | } | 
|  | } | 
|  |  | 
|  |  | 
|  | void rdft(int n, int isgn, double *a, int *ip, double *w) | 
|  | { | 
|  | void makewt(int nw, int *ip, double *w); | 
|  | void makect(int nc, int *ip, double *c); | 
|  | void cftfsub(int n, double *a, int *ip, int nw, double *w); | 
|  | void cftbsub(int n, double *a, int *ip, int nw, double *w); | 
|  | void rftfsub(int n, double *a, int nc, double *c); | 
|  | void rftbsub(int n, double *a, int nc, double *c); | 
|  | int nw, nc; | 
|  | double xi; | 
|  |  | 
|  | nw = ip[0]; | 
|  | if (n > (nw << 2)) { | 
|  | nw = n >> 2; | 
|  | makewt(nw, ip, w); | 
|  | } | 
|  | nc = ip[1]; | 
|  | if (n > (nc << 2)) { | 
|  | nc = n >> 2; | 
|  | makect(nc, ip, w + nw); | 
|  | } | 
|  | if (isgn >= 0) { | 
|  | if (n > 4) { | 
|  | cftfsub(n, a, ip, nw, w); | 
|  | rftfsub(n, a, nc, w + nw); | 
|  | } else if (n == 4) { | 
|  | cftfsub(n, a, ip, nw, w); | 
|  | } | 
|  | xi = a[0] - a[1]; | 
|  | a[0] += a[1]; | 
|  | a[1] = xi; | 
|  | } else { | 
|  | a[1] = 0.5 * (a[0] - a[1]); | 
|  | a[0] -= a[1]; | 
|  | if (n > 4) { | 
|  | rftbsub(n, a, nc, w + nw); | 
|  | cftbsub(n, a, ip, nw, w); | 
|  | } else if (n == 4) { | 
|  | cftbsub(n, a, ip, nw, w); | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  |  | 
|  | void ddct(int n, int isgn, double *a, int *ip, double *w) | 
|  | { | 
|  | void makewt(int nw, int *ip, double *w); | 
|  | void makect(int nc, int *ip, double *c); | 
|  | void cftfsub(int n, double *a, int *ip, int nw, double *w); | 
|  | void cftbsub(int n, double *a, int *ip, int nw, double *w); | 
|  | void rftfsub(int n, double *a, int nc, double *c); | 
|  | void rftbsub(int n, double *a, int nc, double *c); | 
|  | void dctsub(int n, double *a, int nc, double *c); | 
|  | int j, nw, nc; | 
|  | double xr; | 
|  |  | 
|  | nw = ip[0]; | 
|  | if (n > (nw << 2)) { | 
|  | nw = n >> 2; | 
|  | makewt(nw, ip, w); | 
|  | } | 
|  | nc = ip[1]; | 
|  | if (n > nc) { | 
|  | nc = n; | 
|  | makect(nc, ip, w + nw); | 
|  | } | 
|  | if (isgn < 0) { | 
|  | xr = a[n - 1]; | 
|  | for (j = n - 2; j >= 2; j -= 2) { | 
|  | a[j + 1] = a[j] - a[j - 1]; | 
|  | a[j] += a[j - 1]; | 
|  | } | 
|  | a[1] = a[0] - xr; | 
|  | a[0] += xr; | 
|  | if (n > 4) { | 
|  | rftbsub(n, a, nc, w + nw); | 
|  | cftbsub(n, a, ip, nw, w); | 
|  | } else if (n == 4) { | 
|  | cftbsub(n, a, ip, nw, w); | 
|  | } | 
|  | } | 
|  | dctsub(n, a, nc, w + nw); | 
|  | if (isgn >= 0) { | 
|  | if (n > 4) { | 
|  | cftfsub(n, a, ip, nw, w); | 
|  | rftfsub(n, a, nc, w + nw); | 
|  | } else if (n == 4) { | 
|  | cftfsub(n, a, ip, nw, w); | 
|  | } | 
|  | xr = a[0] - a[1]; | 
|  | a[0] += a[1]; | 
|  | for (j = 2; j < n; j += 2) { | 
|  | a[j - 1] = a[j] - a[j + 1]; | 
|  | a[j] += a[j + 1]; | 
|  | } | 
|  | a[n - 1] = xr; | 
|  | } | 
|  | } | 
|  |  | 
|  |  | 
|  | void ddst(int n, int isgn, double *a, int *ip, double *w) | 
|  | { | 
|  | void makewt(int nw, int *ip, double *w); | 
|  | void makect(int nc, int *ip, double *c); | 
|  | void cftfsub(int n, double *a, int *ip, int nw, double *w); | 
|  | void cftbsub(int n, double *a, int *ip, int nw, double *w); | 
|  | void rftfsub(int n, double *a, int nc, double *c); | 
|  | void rftbsub(int n, double *a, int nc, double *c); | 
|  | void dstsub(int n, double *a, int nc, double *c); | 
|  | int j, nw, nc; | 
|  | double xr; | 
|  |  | 
|  | nw = ip[0]; | 
|  | if (n > (nw << 2)) { | 
|  | nw = n >> 2; | 
|  | makewt(nw, ip, w); | 
|  | } | 
|  | nc = ip[1]; | 
|  | if (n > nc) { | 
|  | nc = n; | 
|  | makect(nc, ip, w + nw); | 
|  | } | 
|  | if (isgn < 0) { | 
|  | xr = a[n - 1]; | 
|  | for (j = n - 2; j >= 2; j -= 2) { | 
|  | a[j + 1] = -a[j] - a[j - 1]; | 
|  | a[j] -= a[j - 1]; | 
|  | } | 
|  | a[1] = a[0] + xr; | 
|  | a[0] -= xr; | 
|  | if (n > 4) { | 
|  | rftbsub(n, a, nc, w + nw); | 
|  | cftbsub(n, a, ip, nw, w); | 
|  | } else if (n == 4) { | 
|  | cftbsub(n, a, ip, nw, w); | 
|  | } | 
|  | } | 
|  | dstsub(n, a, nc, w + nw); | 
|  | if (isgn >= 0) { | 
|  | if (n > 4) { | 
|  | cftfsub(n, a, ip, nw, w); | 
|  | rftfsub(n, a, nc, w + nw); | 
|  | } else if (n == 4) { | 
|  | cftfsub(n, a, ip, nw, w); | 
|  | } | 
|  | xr = a[0] - a[1]; | 
|  | a[0] += a[1]; | 
|  | for (j = 2; j < n; j += 2) { | 
|  | a[j - 1] = -a[j] - a[j + 1]; | 
|  | a[j] -= a[j + 1]; | 
|  | } | 
|  | a[n - 1] = -xr; | 
|  | } | 
|  | } | 
|  |  | 
|  |  | 
|  | void dfct(int n, double *a, double *t, int *ip, double *w) | 
|  | { | 
|  | void makewt(int nw, int *ip, double *w); | 
|  | void makect(int nc, int *ip, double *c); | 
|  | void cftfsub(int n, double *a, int *ip, int nw, double *w); | 
|  | void rftfsub(int n, double *a, int nc, double *c); | 
|  | void dctsub(int n, double *a, int nc, double *c); | 
|  | int j, k, l, m, mh, nw, nc; | 
|  | double xr, xi, yr, yi; | 
|  |  | 
|  | nw = ip[0]; | 
|  | if (n > (nw << 3)) { | 
|  | nw = n >> 3; | 
|  | makewt(nw, ip, w); | 
|  | } | 
|  | nc = ip[1]; | 
|  | if (n > (nc << 1)) { | 
|  | nc = n >> 1; | 
|  | makect(nc, ip, w + nw); | 
|  | } | 
|  | m = n >> 1; | 
|  | yi = a[m]; | 
|  | xi = a[0] + a[n]; | 
|  | a[0] -= a[n]; | 
|  | t[0] = xi - yi; | 
|  | t[m] = xi + yi; | 
|  | if (n > 2) { | 
|  | mh = m >> 1; | 
|  | for (j = 1; j < mh; j++) { | 
|  | k = m - j; | 
|  | xr = a[j] - a[n - j]; | 
|  | xi = a[j] + a[n - j]; | 
|  | yr = a[k] - a[n - k]; | 
|  | yi = a[k] + a[n - k]; | 
|  | a[j] = xr; | 
|  | a[k] = yr; | 
|  | t[j] = xi - yi; | 
|  | t[k] = xi + yi; | 
|  | } | 
|  | t[mh] = a[mh] + a[n - mh]; | 
|  | a[mh] -= a[n - mh]; | 
|  | dctsub(m, a, nc, w + nw); | 
|  | if (m > 4) { | 
|  | cftfsub(m, a, ip, nw, w); | 
|  | rftfsub(m, a, nc, w + nw); | 
|  | } else if (m == 4) { | 
|  | cftfsub(m, a, ip, nw, w); | 
|  | } | 
|  | a[n - 1] = a[0] - a[1]; | 
|  | a[1] = a[0] + a[1]; | 
|  | for (j = m - 2; j >= 2; j -= 2) { | 
|  | a[2 * j + 1] = a[j] + a[j + 1]; | 
|  | a[2 * j - 1] = a[j] - a[j + 1]; | 
|  | } | 
|  | l = 2; | 
|  | m = mh; | 
|  | while (m >= 2) { | 
|  | dctsub(m, t, nc, w + nw); | 
|  | if (m > 4) { | 
|  | cftfsub(m, t, ip, nw, w); | 
|  | rftfsub(m, t, nc, w + nw); | 
|  | } else if (m == 4) { | 
|  | cftfsub(m, t, ip, nw, w); | 
|  | } | 
|  | a[n - l] = t[0] - t[1]; | 
|  | a[l] = t[0] + t[1]; | 
|  | k = 0; | 
|  | for (j = 2; j < m; j += 2) { | 
|  | k += l << 2; | 
|  | a[k - l] = t[j] - t[j + 1]; | 
|  | a[k + l] = t[j] + t[j + 1]; | 
|  | } | 
|  | l <<= 1; | 
|  | mh = m >> 1; | 
|  | for (j = 0; j < mh; j++) { | 
|  | k = m - j; | 
|  | t[j] = t[m + k] - t[m + j]; | 
|  | t[k] = t[m + k] + t[m + j]; | 
|  | } | 
|  | t[mh] = t[m + mh]; | 
|  | m = mh; | 
|  | } | 
|  | a[l] = t[0]; | 
|  | a[n] = t[2] - t[1]; | 
|  | a[0] = t[2] + t[1]; | 
|  | } else { | 
|  | a[1] = a[0]; | 
|  | a[2] = t[0]; | 
|  | a[0] = t[1]; | 
|  | } | 
|  | } | 
|  |  | 
|  |  | 
|  | void dfst(int n, double *a, double *t, int *ip, double *w) | 
|  | { | 
|  | void makewt(int nw, int *ip, double *w); | 
|  | void makect(int nc, int *ip, double *c); | 
|  | void cftfsub(int n, double *a, int *ip, int nw, double *w); | 
|  | void rftfsub(int n, double *a, int nc, double *c); | 
|  | void dstsub(int n, double *a, int nc, double *c); | 
|  | int j, k, l, m, mh, nw, nc; | 
|  | double xr, xi, yr, yi; | 
|  |  | 
|  | nw = ip[0]; | 
|  | if (n > (nw << 3)) { | 
|  | nw = n >> 3; | 
|  | makewt(nw, ip, w); | 
|  | } | 
|  | nc = ip[1]; | 
|  | if (n > (nc << 1)) { | 
|  | nc = n >> 1; | 
|  | makect(nc, ip, w + nw); | 
|  | } | 
|  | if (n > 2) { | 
|  | m = n >> 1; | 
|  | mh = m >> 1; | 
|  | for (j = 1; j < mh; j++) { | 
|  | k = m - j; | 
|  | xr = a[j] + a[n - j]; | 
|  | xi = a[j] - a[n - j]; | 
|  | yr = a[k] + a[n - k]; | 
|  | yi = a[k] - a[n - k]; | 
|  | a[j] = xr; | 
|  | a[k] = yr; | 
|  | t[j] = xi + yi; | 
|  | t[k] = xi - yi; | 
|  | } | 
|  | t[0] = a[mh] - a[n - mh]; | 
|  | a[mh] += a[n - mh]; | 
|  | a[0] = a[m]; | 
|  | dstsub(m, a, nc, w + nw); | 
|  | if (m > 4) { | 
|  | cftfsub(m, a, ip, nw, w); | 
|  | rftfsub(m, a, nc, w + nw); | 
|  | } else if (m == 4) { | 
|  | cftfsub(m, a, ip, nw, w); | 
|  | } | 
|  | a[n - 1] = a[1] - a[0]; | 
|  | a[1] = a[0] + a[1]; | 
|  | for (j = m - 2; j >= 2; j -= 2) { | 
|  | a[2 * j + 1] = a[j] - a[j + 1]; | 
|  | a[2 * j - 1] = -a[j] - a[j + 1]; | 
|  | } | 
|  | l = 2; | 
|  | m = mh; | 
|  | while (m >= 2) { | 
|  | dstsub(m, t, nc, w + nw); | 
|  | if (m > 4) { | 
|  | cftfsub(m, t, ip, nw, w); | 
|  | rftfsub(m, t, nc, w + nw); | 
|  | } else if (m == 4) { | 
|  | cftfsub(m, t, ip, nw, w); | 
|  | } | 
|  | a[n - l] = t[1] - t[0]; | 
|  | a[l] = t[0] + t[1]; | 
|  | k = 0; | 
|  | for (j = 2; j < m; j += 2) { | 
|  | k += l << 2; | 
|  | a[k - l] = -t[j] - t[j + 1]; | 
|  | a[k + l] = t[j] - t[j + 1]; | 
|  | } | 
|  | l <<= 1; | 
|  | mh = m >> 1; | 
|  | for (j = 1; j < mh; j++) { | 
|  | k = m - j; | 
|  | t[j] = t[m + k] + t[m + j]; | 
|  | t[k] = t[m + k] - t[m + j]; | 
|  | } | 
|  | t[0] = t[m + mh]; | 
|  | m = mh; | 
|  | } | 
|  | a[l] = t[0]; | 
|  | } | 
|  | a[0] = 0; | 
|  | } | 
|  |  | 
|  |  | 
|  | /* -------- initializing routines -------- */ | 
|  |  | 
|  |  | 
|  | #include <math.h> | 
|  |  | 
|  | void makewt(int nw, int *ip, double *w) | 
|  | { | 
|  | void makeipt(int nw, int *ip); | 
|  | int j, nwh, nw0, nw1; | 
|  | double delta, wn4r, wk1r, wk1i, wk3r, wk3i; | 
|  |  | 
|  | ip[0] = nw; | 
|  | ip[1] = 1; | 
|  | if (nw > 2) { | 
|  | nwh = nw >> 1; | 
|  | delta = atan(1.0) / nwh; | 
|  | wn4r = cos(delta * nwh); | 
|  | w[0] = 1; | 
|  | w[1] = wn4r; | 
|  | if (nwh == 4) { | 
|  | w[2] = cos(delta * 2); | 
|  | w[3] = sin(delta * 2); | 
|  | } else if (nwh > 4) { | 
|  | makeipt(nw, ip); | 
|  | w[2] = 0.5 / cos(delta * 2); | 
|  | w[3] = 0.5 / cos(delta * 6); | 
|  | for (j = 4; j < nwh; j += 4) { | 
|  | w[j] = cos(delta * j); | 
|  | w[j + 1] = sin(delta * j); | 
|  | w[j + 2] = cos(3 * delta * j); | 
|  | w[j + 3] = -sin(3 * delta * j); | 
|  | } | 
|  | } | 
|  | nw0 = 0; | 
|  | while (nwh > 2) { | 
|  | nw1 = nw0 + nwh; | 
|  | nwh >>= 1; | 
|  | w[nw1] = 1; | 
|  | w[nw1 + 1] = wn4r; | 
|  | if (nwh == 4) { | 
|  | wk1r = w[nw0 + 4]; | 
|  | wk1i = w[nw0 + 5]; | 
|  | w[nw1 + 2] = wk1r; | 
|  | w[nw1 + 3] = wk1i; | 
|  | } else if (nwh > 4) { | 
|  | wk1r = w[nw0 + 4]; | 
|  | wk3r = w[nw0 + 6]; | 
|  | w[nw1 + 2] = 0.5 / wk1r; | 
|  | w[nw1 + 3] = 0.5 / wk3r; | 
|  | for (j = 4; j < nwh; j += 4) { | 
|  | wk1r = w[nw0 + 2 * j]; | 
|  | wk1i = w[nw0 + 2 * j + 1]; | 
|  | wk3r = w[nw0 + 2 * j + 2]; | 
|  | wk3i = w[nw0 + 2 * j + 3]; | 
|  | w[nw1 + j] = wk1r; | 
|  | w[nw1 + j + 1] = wk1i; | 
|  | w[nw1 + j + 2] = wk3r; | 
|  | w[nw1 + j + 3] = wk3i; | 
|  | } | 
|  | } | 
|  | nw0 = nw1; | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  |  | 
|  | void makeipt(int nw, int *ip) | 
|  | { | 
|  | int j, l, m, m2, p, q; | 
|  |  | 
|  | ip[2] = 0; | 
|  | ip[3] = 16; | 
|  | m = 2; | 
|  | for (l = nw; l > 32; l >>= 2) { | 
|  | m2 = m << 1; | 
|  | q = m2 << 3; | 
|  | for (j = m; j < m2; j++) { | 
|  | p = ip[j] << 2; | 
|  | ip[m + j] = p; | 
|  | ip[m2 + j] = p + q; | 
|  | } | 
|  | m = m2; | 
|  | } | 
|  | } | 
|  |  | 
|  |  | 
|  | void makect(int nc, int *ip, double *c) | 
|  | { | 
|  | int j, nch; | 
|  | double delta; | 
|  |  | 
|  | ip[1] = nc; | 
|  | if (nc > 1) { | 
|  | nch = nc >> 1; | 
|  | delta = atan(1.0) / nch; | 
|  | c[0] = cos(delta * nch); | 
|  | c[nch] = 0.5 * c[0]; | 
|  | for (j = 1; j < nch; j++) { | 
|  | c[j] = 0.5 * cos(delta * j); | 
|  | c[nc - j] = 0.5 * sin(delta * j); | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  |  | 
|  | /* -------- child routines -------- */ | 
|  |  | 
|  |  | 
|  | #ifdef USE_CDFT_PTHREADS | 
|  | #define USE_CDFT_THREADS | 
|  | #ifndef CDFT_THREADS_BEGIN_N | 
|  | #define CDFT_THREADS_BEGIN_N 8192 | 
|  | #endif | 
|  | #ifndef CDFT_4THREADS_BEGIN_N | 
|  | #define CDFT_4THREADS_BEGIN_N 65536 | 
|  | #endif | 
|  | #include <pthread.h> | 
|  | #include <stdio.h> | 
|  | #include <stdlib.h> | 
|  | #define cdft_thread_t pthread_t | 
|  | #define cdft_thread_create(thp,func,argp) { \ | 
|  | if (pthread_create(thp, NULL, func, (void *) argp) != 0) { \ | 
|  | fprintf(stderr, "cdft thread error\n"); \ | 
|  | exit(1); \ | 
|  | } \ | 
|  | } | 
|  | #define cdft_thread_wait(th) { \ | 
|  | if (pthread_join(th, NULL) != 0) { \ | 
|  | fprintf(stderr, "cdft thread error\n"); \ | 
|  | exit(1); \ | 
|  | } \ | 
|  | } | 
|  | #endif /* USE_CDFT_PTHREADS */ | 
|  |  | 
|  |  | 
|  | #ifdef USE_CDFT_WINTHREADS | 
|  | #define USE_CDFT_THREADS | 
|  | #ifndef CDFT_THREADS_BEGIN_N | 
|  | #define CDFT_THREADS_BEGIN_N 32768 | 
|  | #endif | 
|  | #ifndef CDFT_4THREADS_BEGIN_N | 
|  | #define CDFT_4THREADS_BEGIN_N 524288 | 
|  | #endif | 
|  | #include <windows.h> | 
|  | #include <stdio.h> | 
|  | #include <stdlib.h> | 
|  | #define cdft_thread_t HANDLE | 
|  | #define cdft_thread_create(thp,func,argp) { \ | 
|  | DWORD thid; \ | 
|  | *(thp) = CreateThread(NULL, 0, (LPTHREAD_START_ROUTINE) func, (LPVOID) argp, 0, &thid); \ | 
|  | if (*(thp) == 0) { \ | 
|  | fprintf(stderr, "cdft thread error\n"); \ | 
|  | exit(1); \ | 
|  | } \ | 
|  | } | 
|  | #define cdft_thread_wait(th) { \ | 
|  | WaitForSingleObject(th, INFINITE); \ | 
|  | CloseHandle(th); \ | 
|  | } | 
|  | #endif /* USE_CDFT_WINTHREADS */ | 
|  |  | 
|  |  | 
|  | void cftfsub(int n, double *a, int *ip, int nw, double *w) | 
|  | { | 
|  | void bitrv2(int n, int *ip, double *a); | 
|  | void bitrv216(double *a); | 
|  | void bitrv208(double *a); | 
|  | void cftf1st(int n, double *a, double *w); | 
|  | void cftrec4(int n, double *a, int nw, double *w); | 
|  | void cftleaf(int n, int isplt, double *a, int nw, double *w); | 
|  | void cftfx41(int n, double *a, int nw, double *w); | 
|  | void cftf161(double *a, double *w); | 
|  | void cftf081(double *a, double *w); | 
|  | void cftf040(double *a); | 
|  | void cftx020(double *a); | 
|  | #ifdef USE_CDFT_THREADS | 
|  | void cftrec4_th(int n, double *a, int nw, double *w); | 
|  | #endif /* USE_CDFT_THREADS */ | 
|  |  | 
|  | if (n > 8) { | 
|  | if (n > 32) { | 
|  | cftf1st(n, a, &w[nw - (n >> 2)]); | 
|  | #ifdef USE_CDFT_THREADS | 
|  | if (n > CDFT_THREADS_BEGIN_N) { | 
|  | cftrec4_th(n, a, nw, w); | 
|  | } else | 
|  | #endif /* USE_CDFT_THREADS */ | 
|  | if (n > 512) { | 
|  | cftrec4(n, a, nw, w); | 
|  | } else if (n > 128) { | 
|  | cftleaf(n, 1, a, nw, w); | 
|  | } else { | 
|  | cftfx41(n, a, nw, w); | 
|  | } | 
|  | bitrv2(n, ip, a); | 
|  | } else if (n == 32) { | 
|  | cftf161(a, &w[nw - 8]); | 
|  | bitrv216(a); | 
|  | } else { | 
|  | cftf081(a, w); | 
|  | bitrv208(a); | 
|  | } | 
|  | } else if (n == 8) { | 
|  | cftf040(a); | 
|  | } else if (n == 4) { | 
|  | cftx020(a); | 
|  | } | 
|  | } | 
|  |  | 
|  |  | 
|  | void cftbsub(int n, double *a, int *ip, int nw, double *w) | 
|  | { | 
|  | void bitrv2conj(int n, int *ip, double *a); | 
|  | void bitrv216neg(double *a); | 
|  | void bitrv208neg(double *a); | 
|  | void cftb1st(int n, double *a, double *w); | 
|  | void cftrec4(int n, double *a, int nw, double *w); | 
|  | void cftleaf(int n, int isplt, double *a, int nw, double *w); | 
|  | void cftfx41(int n, double *a, int nw, double *w); | 
|  | void cftf161(double *a, double *w); | 
|  | void cftf081(double *a, double *w); | 
|  | void cftb040(double *a); | 
|  | void cftx020(double *a); | 
|  | #ifdef USE_CDFT_THREADS | 
|  | void cftrec4_th(int n, double *a, int nw, double *w); | 
|  | #endif /* USE_CDFT_THREADS */ | 
|  |  | 
|  | if (n > 8) { | 
|  | if (n > 32) { | 
|  | cftb1st(n, a, &w[nw - (n >> 2)]); | 
|  | #ifdef USE_CDFT_THREADS | 
|  | if (n > CDFT_THREADS_BEGIN_N) { | 
|  | cftrec4_th(n, a, nw, w); | 
|  | } else | 
|  | #endif /* USE_CDFT_THREADS */ | 
|  | if (n > 512) { | 
|  | cftrec4(n, a, nw, w); | 
|  | } else if (n > 128) { | 
|  | cftleaf(n, 1, a, nw, w); | 
|  | } else { | 
|  | cftfx41(n, a, nw, w); | 
|  | } | 
|  | bitrv2conj(n, ip, a); | 
|  | } else if (n == 32) { | 
|  | cftf161(a, &w[nw - 8]); | 
|  | bitrv216neg(a); | 
|  | } else { | 
|  | cftf081(a, w); | 
|  | bitrv208neg(a); | 
|  | } | 
|  | } else if (n == 8) { | 
|  | cftb040(a); | 
|  | } else if (n == 4) { | 
|  | cftx020(a); | 
|  | } | 
|  | } | 
|  |  | 
|  |  | 
|  | void bitrv2(int n, int *ip, double *a) | 
|  | { | 
|  | int j, j1, k, k1, l, m, nh, nm; | 
|  | double xr, xi, yr, yi; | 
|  |  | 
|  | m = 1; | 
|  | for (l = n >> 2; l > 8; l >>= 2) { | 
|  | m <<= 1; | 
|  | } | 
|  | nh = n >> 1; | 
|  | nm = 4 * m; | 
|  | if (l == 8) { | 
|  | for (k = 0; k < m; k++) { | 
|  | for (j = 0; j < k; j++) { | 
|  | j1 = 4 * j + 2 * ip[m + k]; | 
|  | k1 = 4 * k + 2 * ip[m + j]; | 
|  | xr = a[j1]; | 
|  | xi = a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 += nm; | 
|  | k1 += 2 * nm; | 
|  | xr = a[j1]; | 
|  | xi = a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 += nm; | 
|  | k1 -= nm; | 
|  | xr = a[j1]; | 
|  | xi = a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 += nm; | 
|  | k1 += 2 * nm; | 
|  | xr = a[j1]; | 
|  | xi = a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 += nh; | 
|  | k1 += 2; | 
|  | xr = a[j1]; | 
|  | xi = a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 -= nm; | 
|  | k1 -= 2 * nm; | 
|  | xr = a[j1]; | 
|  | xi = a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 -= nm; | 
|  | k1 += nm; | 
|  | xr = a[j1]; | 
|  | xi = a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 -= nm; | 
|  | k1 -= 2 * nm; | 
|  | xr = a[j1]; | 
|  | xi = a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 += 2; | 
|  | k1 += nh; | 
|  | xr = a[j1]; | 
|  | xi = a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 += nm; | 
|  | k1 += 2 * nm; | 
|  | xr = a[j1]; | 
|  | xi = a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 += nm; | 
|  | k1 -= nm; | 
|  | xr = a[j1]; | 
|  | xi = a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 += nm; | 
|  | k1 += 2 * nm; | 
|  | xr = a[j1]; | 
|  | xi = a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 -= nh; | 
|  | k1 -= 2; | 
|  | xr = a[j1]; | 
|  | xi = a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 -= nm; | 
|  | k1 -= 2 * nm; | 
|  | xr = a[j1]; | 
|  | xi = a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 -= nm; | 
|  | k1 += nm; | 
|  | xr = a[j1]; | 
|  | xi = a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 -= nm; | 
|  | k1 -= 2 * nm; | 
|  | xr = a[j1]; | 
|  | xi = a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | } | 
|  | k1 = 4 * k + 2 * ip[m + k]; | 
|  | j1 = k1 + 2; | 
|  | k1 += nh; | 
|  | xr = a[j1]; | 
|  | xi = a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 += nm; | 
|  | k1 += 2 * nm; | 
|  | xr = a[j1]; | 
|  | xi = a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 += nm; | 
|  | k1 -= nm; | 
|  | xr = a[j1]; | 
|  | xi = a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 -= 2; | 
|  | k1 -= nh; | 
|  | xr = a[j1]; | 
|  | xi = a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 += nh + 2; | 
|  | k1 += nh + 2; | 
|  | xr = a[j1]; | 
|  | xi = a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 -= nh - nm; | 
|  | k1 += 2 * nm - 2; | 
|  | xr = a[j1]; | 
|  | xi = a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | } | 
|  | } else { | 
|  | for (k = 0; k < m; k++) { | 
|  | for (j = 0; j < k; j++) { | 
|  | j1 = 4 * j + ip[m + k]; | 
|  | k1 = 4 * k + ip[m + j]; | 
|  | xr = a[j1]; | 
|  | xi = a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 += nm; | 
|  | k1 += nm; | 
|  | xr = a[j1]; | 
|  | xi = a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 += nh; | 
|  | k1 += 2; | 
|  | xr = a[j1]; | 
|  | xi = a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 -= nm; | 
|  | k1 -= nm; | 
|  | xr = a[j1]; | 
|  | xi = a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 += 2; | 
|  | k1 += nh; | 
|  | xr = a[j1]; | 
|  | xi = a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 += nm; | 
|  | k1 += nm; | 
|  | xr = a[j1]; | 
|  | xi = a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 -= nh; | 
|  | k1 -= 2; | 
|  | xr = a[j1]; | 
|  | xi = a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 -= nm; | 
|  | k1 -= nm; | 
|  | xr = a[j1]; | 
|  | xi = a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | } | 
|  | k1 = 4 * k + ip[m + k]; | 
|  | j1 = k1 + 2; | 
|  | k1 += nh; | 
|  | xr = a[j1]; | 
|  | xi = a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 += nm; | 
|  | k1 += nm; | 
|  | xr = a[j1]; | 
|  | xi = a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  |  | 
|  | void bitrv2conj(int n, int *ip, double *a) | 
|  | { | 
|  | int j, j1, k, k1, l, m, nh, nm; | 
|  | double xr, xi, yr, yi; | 
|  |  | 
|  | m = 1; | 
|  | for (l = n >> 2; l > 8; l >>= 2) { | 
|  | m <<= 1; | 
|  | } | 
|  | nh = n >> 1; | 
|  | nm = 4 * m; | 
|  | if (l == 8) { | 
|  | for (k = 0; k < m; k++) { | 
|  | for (j = 0; j < k; j++) { | 
|  | j1 = 4 * j + 2 * ip[m + k]; | 
|  | k1 = 4 * k + 2 * ip[m + j]; | 
|  | xr = a[j1]; | 
|  | xi = -a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = -a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 += nm; | 
|  | k1 += 2 * nm; | 
|  | xr = a[j1]; | 
|  | xi = -a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = -a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 += nm; | 
|  | k1 -= nm; | 
|  | xr = a[j1]; | 
|  | xi = -a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = -a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 += nm; | 
|  | k1 += 2 * nm; | 
|  | xr = a[j1]; | 
|  | xi = -a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = -a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 += nh; | 
|  | k1 += 2; | 
|  | xr = a[j1]; | 
|  | xi = -a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = -a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 -= nm; | 
|  | k1 -= 2 * nm; | 
|  | xr = a[j1]; | 
|  | xi = -a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = -a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 -= nm; | 
|  | k1 += nm; | 
|  | xr = a[j1]; | 
|  | xi = -a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = -a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 -= nm; | 
|  | k1 -= 2 * nm; | 
|  | xr = a[j1]; | 
|  | xi = -a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = -a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 += 2; | 
|  | k1 += nh; | 
|  | xr = a[j1]; | 
|  | xi = -a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = -a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 += nm; | 
|  | k1 += 2 * nm; | 
|  | xr = a[j1]; | 
|  | xi = -a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = -a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 += nm; | 
|  | k1 -= nm; | 
|  | xr = a[j1]; | 
|  | xi = -a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = -a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 += nm; | 
|  | k1 += 2 * nm; | 
|  | xr = a[j1]; | 
|  | xi = -a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = -a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 -= nh; | 
|  | k1 -= 2; | 
|  | xr = a[j1]; | 
|  | xi = -a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = -a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 -= nm; | 
|  | k1 -= 2 * nm; | 
|  | xr = a[j1]; | 
|  | xi = -a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = -a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 -= nm; | 
|  | k1 += nm; | 
|  | xr = a[j1]; | 
|  | xi = -a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = -a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 -= nm; | 
|  | k1 -= 2 * nm; | 
|  | xr = a[j1]; | 
|  | xi = -a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = -a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | } | 
|  | k1 = 4 * k + 2 * ip[m + k]; | 
|  | j1 = k1 + 2; | 
|  | k1 += nh; | 
|  | a[j1 - 1] = -a[j1 - 1]; | 
|  | xr = a[j1]; | 
|  | xi = -a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = -a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | a[k1 + 3] = -a[k1 + 3]; | 
|  | j1 += nm; | 
|  | k1 += 2 * nm; | 
|  | xr = a[j1]; | 
|  | xi = -a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = -a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 += nm; | 
|  | k1 -= nm; | 
|  | xr = a[j1]; | 
|  | xi = -a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = -a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 -= 2; | 
|  | k1 -= nh; | 
|  | xr = a[j1]; | 
|  | xi = -a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = -a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 += nh + 2; | 
|  | k1 += nh + 2; | 
|  | xr = a[j1]; | 
|  | xi = -a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = -a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 -= nh - nm; | 
|  | k1 += 2 * nm - 2; | 
|  | a[j1 - 1] = -a[j1 - 1]; | 
|  | xr = a[j1]; | 
|  | xi = -a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = -a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | a[k1 + 3] = -a[k1 + 3]; | 
|  | } | 
|  | } else { | 
|  | for (k = 0; k < m; k++) { | 
|  | for (j = 0; j < k; j++) { | 
|  | j1 = 4 * j + ip[m + k]; | 
|  | k1 = 4 * k + ip[m + j]; | 
|  | xr = a[j1]; | 
|  | xi = -a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = -a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 += nm; | 
|  | k1 += nm; | 
|  | xr = a[j1]; | 
|  | xi = -a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = -a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 += nh; | 
|  | k1 += 2; | 
|  | xr = a[j1]; | 
|  | xi = -a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = -a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 -= nm; | 
|  | k1 -= nm; | 
|  | xr = a[j1]; | 
|  | xi = -a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = -a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 += 2; | 
|  | k1 += nh; | 
|  | xr = a[j1]; | 
|  | xi = -a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = -a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 += nm; | 
|  | k1 += nm; | 
|  | xr = a[j1]; | 
|  | xi = -a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = -a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 -= nh; | 
|  | k1 -= 2; | 
|  | xr = a[j1]; | 
|  | xi = -a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = -a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | j1 -= nm; | 
|  | k1 -= nm; | 
|  | xr = a[j1]; | 
|  | xi = -a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = -a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | } | 
|  | k1 = 4 * k + ip[m + k]; | 
|  | j1 = k1 + 2; | 
|  | k1 += nh; | 
|  | a[j1 - 1] = -a[j1 - 1]; | 
|  | xr = a[j1]; | 
|  | xi = -a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = -a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | a[k1 + 3] = -a[k1 + 3]; | 
|  | j1 += nm; | 
|  | k1 += nm; | 
|  | a[j1 - 1] = -a[j1 - 1]; | 
|  | xr = a[j1]; | 
|  | xi = -a[j1 + 1]; | 
|  | yr = a[k1]; | 
|  | yi = -a[k1 + 1]; | 
|  | a[j1] = yr; | 
|  | a[j1 + 1] = yi; | 
|  | a[k1] = xr; | 
|  | a[k1 + 1] = xi; | 
|  | a[k1 + 3] = -a[k1 + 3]; | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  |  | 
|  | void bitrv216(double *a) | 
|  | { | 
|  | double x1r, x1i, x2r, x2i, x3r, x3i, x4r, x4i, | 
|  | x5r, x5i, x7r, x7i, x8r, x8i, x10r, x10i, | 
|  | x11r, x11i, x12r, x12i, x13r, x13i, x14r, x14i; | 
|  |  | 
|  | x1r = a[2]; | 
|  | x1i = a[3]; | 
|  | x2r = a[4]; | 
|  | x2i = a[5]; | 
|  | x3r = a[6]; | 
|  | x3i = a[7]; | 
|  | x4r = a[8]; | 
|  | x4i = a[9]; | 
|  | x5r = a[10]; | 
|  | x5i = a[11]; | 
|  | x7r = a[14]; | 
|  | x7i = a[15]; | 
|  | x8r = a[16]; | 
|  | x8i = a[17]; | 
|  | x10r = a[20]; | 
|  | x10i = a[21]; | 
|  | x11r = a[22]; | 
|  | x11i = a[23]; | 
|  | x12r = a[24]; | 
|  | x12i = a[25]; | 
|  | x13r = a[26]; | 
|  | x13i = a[27]; | 
|  | x14r = a[28]; | 
|  | x14i = a[29]; | 
|  | a[2] = x8r; | 
|  | a[3] = x8i; | 
|  | a[4] = x4r; | 
|  | a[5] = x4i; | 
|  | a[6] = x12r; | 
|  | a[7] = x12i; | 
|  | a[8] = x2r; | 
|  | a[9] = x2i; | 
|  | a[10] = x10r; | 
|  | a[11] = x10i; | 
|  | a[14] = x14r; | 
|  | a[15] = x14i; | 
|  | a[16] = x1r; | 
|  | a[17] = x1i; | 
|  | a[20] = x5r; | 
|  | a[21] = x5i; | 
|  | a[22] = x13r; | 
|  | a[23] = x13i; | 
|  | a[24] = x3r; | 
|  | a[25] = x3i; | 
|  | a[26] = x11r; | 
|  | a[27] = x11i; | 
|  | a[28] = x7r; | 
|  | a[29] = x7i; | 
|  | } | 
|  |  | 
|  |  | 
|  | void bitrv216neg(double *a) | 
|  | { | 
|  | double x1r, x1i, x2r, x2i, x3r, x3i, x4r, x4i, | 
|  | x5r, x5i, x6r, x6i, x7r, x7i, x8r, x8i, | 
|  | x9r, x9i, x10r, x10i, x11r, x11i, x12r, x12i, | 
|  | x13r, x13i, x14r, x14i, x15r, x15i; | 
|  |  | 
|  | x1r = a[2]; | 
|  | x1i = a[3]; | 
|  | x2r = a[4]; | 
|  | x2i = a[5]; | 
|  | x3r = a[6]; | 
|  | x3i = a[7]; | 
|  | x4r = a[8]; | 
|  | x4i = a[9]; | 
|  | x5r = a[10]; | 
|  | x5i = a[11]; | 
|  | x6r = a[12]; | 
|  | x6i = a[13]; | 
|  | x7r = a[14]; | 
|  | x7i = a[15]; | 
|  | x8r = a[16]; | 
|  | x8i = a[17]; | 
|  | x9r = a[18]; | 
|  | x9i = a[19]; | 
|  | x10r = a[20]; | 
|  | x10i = a[21]; | 
|  | x11r = a[22]; | 
|  | x11i = a[23]; | 
|  | x12r = a[24]; | 
|  | x12i = a[25]; | 
|  | x13r = a[26]; | 
|  | x13i = a[27]; | 
|  | x14r = a[28]; | 
|  | x14i = a[29]; | 
|  | x15r = a[30]; | 
|  | x15i = a[31]; | 
|  | a[2] = x15r; | 
|  | a[3] = x15i; | 
|  | a[4] = x7r; | 
|  | a[5] = x7i; | 
|  | a[6] = x11r; | 
|  | a[7] = x11i; | 
|  | a[8] = x3r; | 
|  | a[9] = x3i; | 
|  | a[10] = x13r; | 
|  | a[11] = x13i; | 
|  | a[12] = x5r; | 
|  | a[13] = x5i; | 
|  | a[14] = x9r; | 
|  | a[15] = x9i; | 
|  | a[16] = x1r; | 
|  | a[17] = x1i; | 
|  | a[18] = x14r; | 
|  | a[19] = x14i; | 
|  | a[20] = x6r; | 
|  | a[21] = x6i; | 
|  | a[22] = x10r; | 
|  | a[23] = x10i; | 
|  | a[24] = x2r; | 
|  | a[25] = x2i; | 
|  | a[26] = x12r; | 
|  | a[27] = x12i; | 
|  | a[28] = x4r; | 
|  | a[29] = x4i; | 
|  | a[30] = x8r; | 
|  | a[31] = x8i; | 
|  | } | 
|  |  | 
|  |  | 
|  | void bitrv208(double *a) | 
|  | { | 
|  | double x1r, x1i, x3r, x3i, x4r, x4i, x6r, x6i; | 
|  |  | 
|  | x1r = a[2]; | 
|  | x1i = a[3]; | 
|  | x3r = a[6]; | 
|  | x3i = a[7]; | 
|  | x4r = a[8]; | 
|  | x4i = a[9]; | 
|  | x6r = a[12]; | 
|  | x6i = a[13]; | 
|  | a[2] = x4r; | 
|  | a[3] = x4i; | 
|  | a[6] = x6r; | 
|  | a[7] = x6i; | 
|  | a[8] = x1r; | 
|  | a[9] = x1i; | 
|  | a[12] = x3r; | 
|  | a[13] = x3i; | 
|  | } | 
|  |  | 
|  |  | 
|  | void bitrv208neg(double *a) | 
|  | { | 
|  | double x1r, x1i, x2r, x2i, x3r, x3i, x4r, x4i, | 
|  | x5r, x5i, x6r, x6i, x7r, x7i; | 
|  |  | 
|  | x1r = a[2]; | 
|  | x1i = a[3]; | 
|  | x2r = a[4]; | 
|  | x2i = a[5]; | 
|  | x3r = a[6]; | 
|  | x3i = a[7]; | 
|  | x4r = a[8]; | 
|  | x4i = a[9]; | 
|  | x5r = a[10]; | 
|  | x5i = a[11]; | 
|  | x6r = a[12]; | 
|  | x6i = a[13]; | 
|  | x7r = a[14]; | 
|  | x7i = a[15]; | 
|  | a[2] = x7r; | 
|  | a[3] = x7i; | 
|  | a[4] = x3r; | 
|  | a[5] = x3i; | 
|  | a[6] = x5r; | 
|  | a[7] = x5i; | 
|  | a[8] = x1r; | 
|  | a[9] = x1i; | 
|  | a[10] = x6r; | 
|  | a[11] = x6i; | 
|  | a[12] = x2r; | 
|  | a[13] = x2i; | 
|  | a[14] = x4r; | 
|  | a[15] = x4i; | 
|  | } | 
|  |  | 
|  |  | 
|  | void cftf1st(int n, double *a, double *w) | 
|  | { | 
|  | int j, j0, j1, j2, j3, k, m, mh; | 
|  | double wn4r, csc1, csc3, wk1r, wk1i, wk3r, wk3i, | 
|  | wd1r, wd1i, wd3r, wd3i; | 
|  | double x0r, x0i, x1r, x1i, x2r, x2i, x3r, x3i, | 
|  | y0r, y0i, y1r, y1i, y2r, y2i, y3r, y3i; | 
|  |  | 
|  | mh = n >> 3; | 
|  | m = 2 * mh; | 
|  | j1 = m; | 
|  | j2 = j1 + m; | 
|  | j3 = j2 + m; | 
|  | x0r = a[0] + a[j2]; | 
|  | x0i = a[1] + a[j2 + 1]; | 
|  | x1r = a[0] - a[j2]; | 
|  | x1i = a[1] - a[j2 + 1]; | 
|  | x2r = a[j1] + a[j3]; | 
|  | x2i = a[j1 + 1] + a[j3 + 1]; | 
|  | x3r = a[j1] - a[j3]; | 
|  | x3i = a[j1 + 1] - a[j3 + 1]; | 
|  | a[0] = x0r + x2r; | 
|  | a[1] = x0i + x2i; | 
|  | a[j1] = x0r - x2r; | 
|  | a[j1 + 1] = x0i - x2i; | 
|  | a[j2] = x1r - x3i; | 
|  | a[j2 + 1] = x1i + x3r; | 
|  | a[j3] = x1r + x3i; | 
|  | a[j3 + 1] = x1i - x3r; | 
|  | wn4r = w[1]; | 
|  | csc1 = w[2]; | 
|  | csc3 = w[3]; | 
|  | wd1r = 1; | 
|  | wd1i = 0; | 
|  | wd3r = 1; | 
|  | wd3i = 0; | 
|  | k = 0; | 
|  | for (j = 2; j < mh - 2; j += 4) { | 
|  | k += 4; | 
|  | wk1r = csc1 * (wd1r + w[k]); | 
|  | wk1i = csc1 * (wd1i + w[k + 1]); | 
|  | wk3r = csc3 * (wd3r + w[k + 2]); | 
|  | wk3i = csc3 * (wd3i + w[k + 3]); | 
|  | wd1r = w[k]; | 
|  | wd1i = w[k + 1]; | 
|  | wd3r = w[k + 2]; | 
|  | wd3i = w[k + 3]; | 
|  | j1 = j + m; | 
|  | j2 = j1 + m; | 
|  | j3 = j2 + m; | 
|  | x0r = a[j] + a[j2]; | 
|  | x0i = a[j + 1] + a[j2 + 1]; | 
|  | x1r = a[j] - a[j2]; | 
|  | x1i = a[j + 1] - a[j2 + 1]; | 
|  | y0r = a[j + 2] + a[j2 + 2]; | 
|  | y0i = a[j + 3] + a[j2 + 3]; | 
|  | y1r = a[j + 2] - a[j2 + 2]; | 
|  | y1i = a[j + 3] - a[j2 + 3]; | 
|  | x2r = a[j1] + a[j3]; | 
|  | x2i = a[j1 + 1] + a[j3 + 1]; | 
|  | x3r = a[j1] - a[j3]; | 
|  | x3i = a[j1 + 1] - a[j3 + 1]; | 
|  | y2r = a[j1 + 2] + a[j3 + 2]; | 
|  | y2i = a[j1 + 3] + a[j3 + 3]; | 
|  | y3r = a[j1 + 2] - a[j3 + 2]; | 
|  | y3i = a[j1 + 3] - a[j3 + 3]; | 
|  | a[j] = x0r + x2r; | 
|  | a[j + 1] = x0i + x2i; | 
|  | a[j + 2] = y0r + y2r; | 
|  | a[j + 3] = y0i + y2i; | 
|  | a[j1] = x0r - x2r; | 
|  | a[j1 + 1] = x0i - x2i; | 
|  | a[j1 + 2] = y0r - y2r; | 
|  | a[j1 + 3] = y0i - y2i; | 
|  | x0r = x1r - x3i; | 
|  | x0i = x1i + x3r; | 
|  | a[j2] = wk1r * x0r - wk1i * x0i; | 
|  | a[j2 + 1] = wk1r * x0i + wk1i * x0r; | 
|  | x0r = y1r - y3i; | 
|  | x0i = y1i + y3r; | 
|  | a[j2 + 2] = wd1r * x0r - wd1i * x0i; | 
|  | a[j2 + 3] = wd1r * x0i + wd1i * x0r; | 
|  | x0r = x1r + x3i; | 
|  | x0i = x1i - x3r; | 
|  | a[j3] = wk3r * x0r + wk3i * x0i; | 
|  | a[j3 + 1] = wk3r * x0i - wk3i * x0r; | 
|  | x0r = y1r + y3i; | 
|  | x0i = y1i - y3r; | 
|  | a[j3 + 2] = wd3r * x0r + wd3i * x0i; | 
|  | a[j3 + 3] = wd3r * x0i - wd3i * x0r; | 
|  | j0 = m - j; | 
|  | j1 = j0 + m; | 
|  | j2 = j1 + m; | 
|  | j3 = j2 + m; | 
|  | x0r = a[j0] + a[j2]; | 
|  | x0i = a[j0 + 1] + a[j2 + 1]; | 
|  | x1r = a[j0] - a[j2]; | 
|  | x1i = a[j0 + 1] - a[j2 + 1]; | 
|  | y0r = a[j0 - 2] + a[j2 - 2]; | 
|  | y0i = a[j0 - 1] + a[j2 - 1]; | 
|  | y1r = a[j0 - 2] - a[j2 - 2]; | 
|  | y1i = a[j0 - 1] - a[j2 - 1]; | 
|  | x2r = a[j1] + a[j3]; | 
|  | x2i = a[j1 + 1] + a[j3 + 1]; | 
|  | x3r = a[j1] - a[j3]; | 
|  | x3i = a[j1 + 1] - a[j3 + 1]; | 
|  | y2r = a[j1 - 2] + a[j3 - 2]; | 
|  | y2i = a[j1 - 1] + a[j3 - 1]; | 
|  | y3r = a[j1 - 2] - a[j3 - 2]; | 
|  | y3i = a[j1 - 1] - a[j3 - 1]; | 
|  | a[j0] = x0r + x2r; | 
|  | a[j0 + 1] = x0i + x2i; | 
|  | a[j0 - 2] = y0r + y2r; | 
|  | a[j0 - 1] = y0i + y2i; | 
|  | a[j1] = x0r - x2r; | 
|  | a[j1 + 1] = x0i - x2i; | 
|  | a[j1 - 2] = y0r - y2r; | 
|  | a[j1 - 1] = y0i - y2i; | 
|  | x0r = x1r - x3i; | 
|  | x0i = x1i + x3r; | 
|  | a[j2] = wk1i * x0r - wk1r * x0i; | 
|  | a[j2 + 1] = wk1i * x0i + wk1r * x0r; | 
|  | x0r = y1r - y3i; | 
|  | x0i = y1i + y3r; | 
|  | a[j2 - 2] = wd1i * x0r - wd1r * x0i; | 
|  | a[j2 - 1] = wd1i * x0i + wd1r * x0r; | 
|  | x0r = x1r + x3i; | 
|  | x0i = x1i - x3r; | 
|  | a[j3] = wk3i * x0r + wk3r * x0i; | 
|  | a[j3 + 1] = wk3i * x0i - wk3r * x0r; | 
|  | x0r = y1r + y3i; | 
|  | x0i = y1i - y3r; | 
|  | a[j3 - 2] = wd3i * x0r + wd3r * x0i; | 
|  | a[j3 - 1] = wd3i * x0i - wd3r * x0r; | 
|  | } | 
|  | wk1r = csc1 * (wd1r + wn4r); | 
|  | wk1i = csc1 * (wd1i + wn4r); | 
|  | wk3r = csc3 * (wd3r - wn4r); | 
|  | wk3i = csc3 * (wd3i - wn4r); | 
|  | j0 = mh; | 
|  | j1 = j0 + m; | 
|  | j2 = j1 + m; | 
|  | j3 = j2 + m; | 
|  | x0r = a[j0 - 2] + a[j2 - 2]; | 
|  | x0i = a[j0 - 1] + a[j2 - 1]; | 
|  | x1r = a[j0 - 2] - a[j2 - 2]; | 
|  | x1i = a[j0 - 1] - a[j2 - 1]; | 
|  | x2r = a[j1 - 2] + a[j3 - 2]; | 
|  | x2i = a[j1 - 1] + a[j3 - 1]; | 
|  | x3r = a[j1 - 2] - a[j3 - 2]; | 
|  | x3i = a[j1 - 1] - a[j3 - 1]; | 
|  | a[j0 - 2] = x0r + x2r; | 
|  | a[j0 - 1] = x0i + x2i; | 
|  | a[j1 - 2] = x0r - x2r; | 
|  | a[j1 - 1] = x0i - x2i; | 
|  | x0r = x1r - x3i; | 
|  | x0i = x1i + x3r; | 
|  | a[j2 - 2] = wk1r * x0r - wk1i * x0i; | 
|  | a[j2 - 1] = wk1r * x0i + wk1i * x0r; | 
|  | x0r = x1r + x3i; | 
|  | x0i = x1i - x3r; | 
|  | a[j3 - 2] = wk3r * x0r + wk3i * x0i; | 
|  | a[j3 - 1] = wk3r * x0i - wk3i * x0r; | 
|  | x0r = a[j0] + a[j2]; | 
|  | x0i = a[j0 + 1] + a[j2 + 1]; | 
|  | x1r = a[j0] - a[j2]; | 
|  | x1i = a[j0 + 1] - a[j2 + 1]; | 
|  | x2r = a[j1] + a[j3]; | 
|  | x2i = a[j1 + 1] + a[j3 + 1]; | 
|  | x3r = a[j1] - a[j3]; | 
|  | x3i = a[j1 + 1] - a[j3 + 1]; | 
|  | a[j0] = x0r + x2r; | 
|  | a[j0 + 1] = x0i + x2i; | 
|  | a[j1] = x0r - x2r; | 
|  | a[j1 + 1] = x0i - x2i; | 
|  | x0r = x1r - x3i; | 
|  | x0i = x1i + x3r; | 
|  | a[j2] = wn4r * (x0r - x0i); | 
|  | a[j2 + 1] = wn4r * (x0i + x0r); | 
|  | x0r = x1r + x3i; | 
|  | x0i = x1i - x3r; | 
|  | a[j3] = -wn4r * (x0r + x0i); | 
|  | a[j3 + 1] = -wn4r * (x0i - x0r); | 
|  | x0r = a[j0 + 2] + a[j2 + 2]; | 
|  | x0i = a[j0 + 3] + a[j2 + 3]; | 
|  | x1r = a[j0 + 2] - a[j2 + 2]; | 
|  | x1i = a[j0 + 3] - a[j2 + 3]; | 
|  | x2r = a[j1 + 2] + a[j3 + 2]; | 
|  | x2i = a[j1 + 3] + a[j3 + 3]; | 
|  | x3r = a[j1 + 2] - a[j3 + 2]; | 
|  | x3i = a[j1 + 3] - a[j3 + 3]; | 
|  | a[j0 + 2] = x0r + x2r; | 
|  | a[j0 + 3] = x0i + x2i; | 
|  | a[j1 + 2] = x0r - x2r; | 
|  | a[j1 + 3] = x0i - x2i; | 
|  | x0r = x1r - x3i; | 
|  | x0i = x1i + x3r; | 
|  | a[j2 + 2] = wk1i * x0r - wk1r * x0i; | 
|  | a[j2 + 3] = wk1i * x0i + wk1r * x0r; | 
|  | x0r = x1r + x3i; | 
|  | x0i = x1i - x3r; | 
|  | a[j3 + 2] = wk3i * x0r + wk3r * x0i; | 
|  | a[j3 + 3] = wk3i * x0i - wk3r * x0r; | 
|  | } | 
|  |  | 
|  |  | 
|  | void cftb1st(int n, double *a, double *w) | 
|  | { | 
|  | int j, j0, j1, j2, j3, k, m, mh; | 
|  | double wn4r, csc1, csc3, wk1r, wk1i, wk3r, wk3i, | 
|  | wd1r, wd1i, wd3r, wd3i; | 
|  | double x0r, x0i, x1r, x1i, x2r, x2i, x3r, x3i, | 
|  | y0r, y0i, y1r, y1i, y2r, y2i, y3r, y3i; | 
|  |  | 
|  | mh = n >> 3; | 
|  | m = 2 * mh; | 
|  | j1 = m; | 
|  | j2 = j1 + m; | 
|  | j3 = j2 + m; | 
|  | x0r = a[0] + a[j2]; | 
|  | x0i = -a[1] - a[j2 + 1]; | 
|  | x1r = a[0] - a[j2]; | 
|  | x1i = -a[1] + a[j2 + 1]; | 
|  | x2r = a[j1] + a[j3]; | 
|  | x2i = a[j1 + 1] + a[j3 + 1]; | 
|  | x3r = a[j1] - a[j3]; | 
|  | x3i = a[j1 + 1] - a[j3 + 1]; | 
|  | a[0] = x0r + x2r; | 
|  | a[1] = x0i - x2i; | 
|  | a[j1] = x0r - x2r; | 
|  | a[j1 + 1] = x0i + x2i; | 
|  | a[j2] = x1r + x3i; | 
|  | a[j2 + 1] = x1i + x3r; | 
|  | a[j3] = x1r - x3i; | 
|  | a[j3 + 1] = x1i - x3r; | 
|  | wn4r = w[1]; | 
|  | csc1 = w[2]; | 
|  | csc3 = w[3]; | 
|  | wd1r = 1; | 
|  | wd1i = 0; | 
|  | wd3r = 1; | 
|  | wd3i = 0; | 
|  | k = 0; | 
|  | for (j = 2; j < mh - 2; j += 4) { | 
|  | k += 4; | 
|  | wk1r = csc1 * (wd1r + w[k]); | 
|  | wk1i = csc1 * (wd1i + w[k + 1]); | 
|  | wk3r = csc3 * (wd3r + w[k + 2]); | 
|  | wk3i = csc3 * (wd3i + w[k + 3]); | 
|  | wd1r = w[k]; | 
|  | wd1i = w[k + 1]; | 
|  | wd3r = w[k + 2]; | 
|  | wd3i = w[k + 3]; | 
|  | j1 = j + m; | 
|  | j2 = j1 + m; | 
|  | j3 = j2 + m; | 
|  | x0r = a[j] + a[j2]; | 
|  | x0i = -a[j + 1] - a[j2 + 1]; | 
|  | x1r = a[j] - a[j2]; | 
|  | x1i = -a[j + 1] + a[j2 + 1]; | 
|  | y0r = a[j + 2] + a[j2 + 2]; | 
|  | y0i = -a[j + 3] - a[j2 + 3]; | 
|  | y1r = a[j + 2] - a[j2 + 2]; | 
|  | y1i = -a[j + 3] + a[j2 + 3]; | 
|  | x2r = a[j1] + a[j3]; | 
|  | x2i = a[j1 + 1] + a[j3 + 1]; | 
|  | x3r = a[j1] - a[j3]; | 
|  | x3i = a[j1 + 1] - a[j3 + 1]; | 
|  | y2r = a[j1 + 2] + a[j3 + 2]; | 
|  | y2i = a[j1 + 3] + a[j3 + 3]; | 
|  | y3r = a[j1 + 2] - a[j3 + 2]; | 
|  | y3i = a[j1 + 3] - a[j3 + 3]; | 
|  | a[j] = x0r + x2r; | 
|  | a[j + 1] = x0i - x2i; | 
|  | a[j + 2] = y0r + y2r; | 
|  | a[j + 3] = y0i - y2i; | 
|  | a[j1] = x0r - x2r; | 
|  | a[j1 + 1] = x0i + x2i; | 
|  | a[j1 + 2] = y0r - y2r; | 
|  | a[j1 + 3] = y0i + y2i; | 
|  | x0r = x1r + x3i; | 
|  | x0i = x1i + x3r; | 
|  | a[j2] = wk1r * x0r - wk1i * x0i; | 
|  | a[j2 + 1] = wk1r * x0i + wk1i * x0r; | 
|  | x0r = y1r + y3i; | 
|  | x0i = y1i + y3r; | 
|  | a[j2 + 2] = wd1r * x0r - wd1i * x0i; | 
|  | a[j2 + 3] = wd1r * x0i + wd1i * x0r; | 
|  | x0r = x1r - x3i; | 
|  | x0i = x1i - x3r; | 
|  | a[j3] = wk3r * x0r + wk3i * x0i; | 
|  | a[j3 + 1] = wk3r * x0i - wk3i * x0r; | 
|  | x0r = y1r - y3i; | 
|  | x0i = y1i - y3r; | 
|  | a[j3 + 2] = wd3r * x0r + wd3i * x0i; | 
|  | a[j3 + 3] = wd3r * x0i - wd3i * x0r; | 
|  | j0 = m - j; | 
|  | j1 = j0 + m; | 
|  | j2 = j1 + m; | 
|  | j3 = j2 + m; | 
|  | x0r = a[j0] + a[j2]; | 
|  | x0i = -a[j0 + 1] - a[j2 + 1]; | 
|  | x1r = a[j0] - a[j2]; | 
|  | x1i = -a[j0 + 1] + a[j2 + 1]; | 
|  | y0r = a[j0 - 2] + a[j2 - 2]; | 
|  | y0i = -a[j0 - 1] - a[j2 - 1]; | 
|  | y1r = a[j0 - 2] - a[j2 - 2]; | 
|  | y1i = -a[j0 - 1] + a[j2 - 1]; | 
|  | x2r = a[j1] + a[j3]; | 
|  | x2i = a[j1 + 1] + a[j3 + 1]; | 
|  | x3r = a[j1] - a[j3]; | 
|  | x3i = a[j1 + 1] - a[j3 + 1]; | 
|  | y2r = a[j1 - 2] + a[j3 - 2]; | 
|  | y2i = a[j1 - 1] + a[j3 - 1]; | 
|  | y3r = a[j1 - 2] - a[j3 - 2]; | 
|  | y3i = a[j1 - 1] - a[j3 - 1]; | 
|  | a[j0] = x0r + x2r; | 
|  | a[j0 + 1] = x0i - x2i; | 
|  | a[j0 - 2] = y0r + y2r; | 
|  | a[j0 - 1] = y0i - y2i; | 
|  | a[j1] = x0r - x2r; | 
|  | a[j1 + 1] = x0i + x2i; | 
|  | a[j1 - 2] = y0r - y2r; | 
|  | a[j1 - 1] = y0i + y2i; | 
|  | x0r = x1r + x3i; | 
|  | x0i = x1i + x3r; | 
|  | a[j2] = wk1i * x0r - wk1r * x0i; | 
|  | a[j2 + 1] = wk1i * x0i + wk1r * x0r; | 
|  | x0r = y1r + y3i; | 
|  | x0i = y1i + y3r; | 
|  | a[j2 - 2] = wd1i * x0r - wd1r * x0i; | 
|  | a[j2 - 1] = wd1i * x0i + wd1r * x0r; | 
|  | x0r = x1r - x3i; | 
|  | x0i = x1i - x3r; | 
|  | a[j3] = wk3i * x0r + wk3r * x0i; | 
|  | a[j3 + 1] = wk3i * x0i - wk3r * x0r; | 
|  | x0r = y1r - y3i; | 
|  | x0i = y1i - y3r; | 
|  | a[j3 - 2] = wd3i * x0r + wd3r * x0i; | 
|  | a[j3 - 1] = wd3i * x0i - wd3r * x0r; | 
|  | } | 
|  | wk1r = csc1 * (wd1r + wn4r); | 
|  | wk1i = csc1 * (wd1i + wn4r); | 
|  | wk3r = csc3 * (wd3r - wn4r); | 
|  | wk3i = csc3 * (wd3i - wn4r); | 
|  | j0 = mh; | 
|  | j1 = j0 + m; | 
|  | j2 = j1 + m; | 
|  | j3 = j2 + m; | 
|  | x0r = a[j0 - 2] + a[j2 - 2]; | 
|  | x0i = -a[j0 - 1] - a[j2 - 1]; | 
|  | x1r = a[j0 - 2] - a[j2 - 2]; | 
|  | x1i = -a[j0 - 1] + a[j2 - 1]; | 
|  | x2r = a[j1 - 2] + a[j3 - 2]; | 
|  | x2i = a[j1 - 1] + a[j3 - 1]; | 
|  | x3r = a[j1 - 2] - a[j3 - 2]; | 
|  | x3i = a[j1 - 1] - a[j3 - 1]; | 
|  | a[j0 - 2] = x0r + x2r; | 
|  | a[j0 - 1] = x0i - x2i; | 
|  | a[j1 - 2] = x0r - x2r; | 
|  | a[j1 - 1] = x0i + x2i; | 
|  | x0r = x1r + x3i; | 
|  | x0i = x1i + x3r; | 
|  | a[j2 - 2] = wk1r * x0r - wk1i * x0i; | 
|  | a[j2 - 1] = wk1r * x0i + wk1i * x0r; | 
|  | x0r = x1r - x3i; | 
|  | x0i = x1i - x3r; | 
|  | a[j3 - 2] = wk3r * x0r + wk3i * x0i; | 
|  | a[j3 - 1] = wk3r * x0i - wk3i * x0r; | 
|  | x0r = a[j0] + a[j2]; | 
|  | x0i = -a[j0 + 1] - a[j2 + 1]; | 
|  | x1r = a[j0] - a[j2]; | 
|  | x1i = -a[j0 + 1] + a[j2 + 1]; | 
|  | x2r = a[j1] + a[j3]; | 
|  | x2i = a[j1 + 1] + a[j3 + 1]; | 
|  | x3r = a[j1] - a[j3]; | 
|  | x3i = a[j1 + 1] - a[j3 + 1]; | 
|  | a[j0] = x0r + x2r; | 
|  | a[j0 + 1] = x0i - x2i; | 
|  | a[j1] = x0r - x2r; | 
|  | a[j1 + 1] = x0i + x2i; | 
|  | x0r = x1r + x3i; | 
|  | x0i = x1i + x3r; | 
|  | a[j2] = wn4r * (x0r - x0i); | 
|  | a[j2 + 1] = wn4r * (x0i + x0r); | 
|  | x0r = x1r - x3i; | 
|  | x0i = x1i - x3r; | 
|  | a[j3] = -wn4r * (x0r + x0i); | 
|  | a[j3 + 1] = -wn4r * (x0i - x0r); | 
|  | x0r = a[j0 + 2] + a[j2 + 2]; | 
|  | x0i = -a[j0 + 3] - a[j2 + 3]; | 
|  | x1r = a[j0 + 2] - a[j2 + 2]; | 
|  | x1i = -a[j0 + 3] + a[j2 + 3]; | 
|  | x2r = a[j1 + 2] + a[j3 + 2]; | 
|  | x2i = a[j1 + 3] + a[j3 + 3]; | 
|  | x3r = a[j1 + 2] - a[j3 + 2]; | 
|  | x3i = a[j1 + 3] - a[j3 + 3]; | 
|  | a[j0 + 2] = x0r + x2r; | 
|  | a[j0 + 3] = x0i - x2i; | 
|  | a[j1 + 2] = x0r - x2r; | 
|  | a[j1 + 3] = x0i + x2i; | 
|  | x0r = x1r + x3i; | 
|  | x0i = x1i + x3r; | 
|  | a[j2 + 2] = wk1i * x0r - wk1r * x0i; | 
|  | a[j2 + 3] = wk1i * x0i + wk1r * x0r; | 
|  | x0r = x1r - x3i; | 
|  | x0i = x1i - x3r; | 
|  | a[j3 + 2] = wk3i * x0r + wk3r * x0i; | 
|  | a[j3 + 3] = wk3i * x0i - wk3r * x0r; | 
|  | } | 
|  |  | 
|  |  | 
|  | #ifdef USE_CDFT_THREADS | 
|  | struct cdft_arg_st { | 
|  | int n0; | 
|  | int n; | 
|  | double *a; | 
|  | int nw; | 
|  | double *w; | 
|  | }; | 
|  | typedef struct cdft_arg_st cdft_arg_t; | 
|  |  | 
|  |  | 
|  | void cftrec4_th(int n, double *a, int nw, double *w) | 
|  | { | 
|  | void *cftrec1_th(void *p); | 
|  | void *cftrec2_th(void *p); | 
|  | int i, idiv4, m, nthread; | 
|  | cdft_thread_t th[4]; | 
|  | cdft_arg_t ag[4]; | 
|  |  | 
|  | nthread = 2; | 
|  | idiv4 = 0; | 
|  | m = n >> 1; | 
|  | if (n > CDFT_4THREADS_BEGIN_N) { | 
|  | nthread = 4; | 
|  | idiv4 = 1; | 
|  | m >>= 1; | 
|  | } | 
|  | for (i = 0; i < nthread; i++) { | 
|  | ag[i].n0 = n; | 
|  | ag[i].n = m; | 
|  | ag[i].a = &a[i * m]; | 
|  | ag[i].nw = nw; | 
|  | ag[i].w = w; | 
|  | if (i != idiv4) { | 
|  | cdft_thread_create(&th[i], cftrec1_th, &ag[i]); | 
|  | } else { | 
|  | cdft_thread_create(&th[i], cftrec2_th, &ag[i]); | 
|  | } | 
|  | } | 
|  | for (i = 0; i < nthread; i++) { | 
|  | cdft_thread_wait(th[i]); | 
|  | } | 
|  | } | 
|  |  | 
|  |  | 
|  | void *cftrec1_th(void *p) | 
|  | { | 
|  | int cfttree(int n, int j, int k, double *a, int nw, double *w); | 
|  | void cftleaf(int n, int isplt, double *a, int nw, double *w); | 
|  | void cftmdl1(int n, double *a, double *w); | 
|  | int isplt, j, k, m, n, n0, nw; | 
|  | double *a, *w; | 
|  |  | 
|  | n0 = ((cdft_arg_t *) p)->n0; | 
|  | n = ((cdft_arg_t *) p)->n; | 
|  | a = ((cdft_arg_t *) p)->a; | 
|  | nw = ((cdft_arg_t *) p)->nw; | 
|  | w = ((cdft_arg_t *) p)->w; | 
|  | m = n0; | 
|  | while (m > 512) { | 
|  | m >>= 2; | 
|  | cftmdl1(m, &a[n - m], &w[nw - (m >> 1)]); | 
|  | } | 
|  | cftleaf(m, 1, &a[n - m], nw, w); | 
|  | k = 0; | 
|  | for (j = n - m; j > 0; j -= m) { | 
|  | k++; | 
|  | isplt = cfttree(m, j, k, a, nw, w); | 
|  | cftleaf(m, isplt, &a[j - m], nw, w); | 
|  | } | 
|  | return (void *) 0; | 
|  | } | 
|  |  | 
|  |  | 
|  | void *cftrec2_th(void *p) | 
|  | { | 
|  | int cfttree(int n, int j, int k, double *a, int nw, double *w); | 
|  | void cftleaf(int n, int isplt, double *a, int nw, double *w); | 
|  | void cftmdl2(int n, double *a, double *w); | 
|  | int isplt, j, k, m, n, n0, nw; | 
|  | double *a, *w; | 
|  |  | 
|  | n0 = ((cdft_arg_t *) p)->n0; | 
|  | n = ((cdft_arg_t *) p)->n; | 
|  | a = ((cdft_arg_t *) p)->a; | 
|  | nw = ((cdft_arg_t *) p)->nw; | 
|  | w = ((cdft_arg_t *) p)->w; | 
|  | k = 1; | 
|  | m = n0; | 
|  | while (m > 512) { | 
|  | m >>= 2; | 
|  | k <<= 2; | 
|  | cftmdl2(m, &a[n - m], &w[nw - m]); | 
|  | } | 
|  | cftleaf(m, 0, &a[n - m], nw, w); | 
|  | k >>= 1; | 
|  | for (j = n - m; j > 0; j -= m) { | 
|  | k++; | 
|  | isplt = cfttree(m, j, k, a, nw, w); | 
|  | cftleaf(m, isplt, &a[j - m], nw, w); | 
|  | } | 
|  | return (void *) 0; | 
|  | } | 
|  | #endif /* USE_CDFT_THREADS */ | 
|  |  | 
|  |  | 
|  | void cftrec4(int n, double *a, int nw, double *w) | 
|  | { | 
|  | int cfttree(int n, int j, int k, double *a, int nw, double *w); | 
|  | void cftleaf(int n, int isplt, double *a, int nw, double *w); | 
|  | void cftmdl1(int n, double *a, double *w); | 
|  | int isplt, j, k, m; | 
|  |  | 
|  | m = n; | 
|  | while (m > 512) { | 
|  | m >>= 2; | 
|  | cftmdl1(m, &a[n - m], &w[nw - (m >> 1)]); | 
|  | } | 
|  | cftleaf(m, 1, &a[n - m], nw, w); | 
|  | k = 0; | 
|  | for (j = n - m; j > 0; j -= m) { | 
|  | k++; | 
|  | isplt = cfttree(m, j, k, a, nw, w); | 
|  | cftleaf(m, isplt, &a[j - m], nw, w); | 
|  | } | 
|  | } | 
|  |  | 
|  |  | 
|  | int cfttree(int n, int j, int k, double *a, int nw, double *w) | 
|  | { | 
|  | void cftmdl1(int n, double *a, double *w); | 
|  | void cftmdl2(int n, double *a, double *w); | 
|  | int i, isplt, m; | 
|  |  | 
|  | if ((k & 3) != 0) { | 
|  | isplt = k & 1; | 
|  | if (isplt != 0) { | 
|  | cftmdl1(n, &a[j - n], &w[nw - (n >> 1)]); | 
|  | } else { | 
|  | cftmdl2(n, &a[j - n], &w[nw - n]); | 
|  | } | 
|  | } else { | 
|  | m = n; | 
|  | for (i = k; (i & 3) == 0; i >>= 2) { | 
|  | m <<= 2; | 
|  | } | 
|  | isplt = i & 1; | 
|  | if (isplt != 0) { | 
|  | while (m > 128) { | 
|  | cftmdl1(m, &a[j - m], &w[nw - (m >> 1)]); | 
|  | m >>= 2; | 
|  | } | 
|  | } else { | 
|  | while (m > 128) { | 
|  | cftmdl2(m, &a[j - m], &w[nw - m]); | 
|  | m >>= 2; | 
|  | } | 
|  | } | 
|  | } | 
|  | return isplt; | 
|  | } | 
|  |  | 
|  |  | 
|  | void cftleaf(int n, int isplt, double *a, int nw, double *w) | 
|  | { | 
|  | void cftmdl1(int n, double *a, double *w); | 
|  | void cftmdl2(int n, double *a, double *w); | 
|  | void cftf161(double *a, double *w); | 
|  | void cftf162(double *a, double *w); | 
|  | void cftf081(double *a, double *w); | 
|  | void cftf082(double *a, double *w); | 
|  |  | 
|  | if (n == 512) { | 
|  | cftmdl1(128, a, &w[nw - 64]); | 
|  | cftf161(a, &w[nw - 8]); | 
|  | cftf162(&a[32], &w[nw - 32]); | 
|  | cftf161(&a[64], &w[nw - 8]); | 
|  | cftf161(&a[96], &w[nw - 8]); | 
|  | cftmdl2(128, &a[128], &w[nw - 128]); | 
|  | cftf161(&a[128], &w[nw - 8]); | 
|  | cftf162(&a[160], &w[nw - 32]); | 
|  | cftf161(&a[192], &w[nw - 8]); | 
|  | cftf162(&a[224], &w[nw - 32]); | 
|  | cftmdl1(128, &a[256], &w[nw - 64]); | 
|  | cftf161(&a[256], &w[nw - 8]); | 
|  | cftf162(&a[288], &w[nw - 32]); | 
|  | cftf161(&a[320], &w[nw - 8]); | 
|  | cftf161(&a[352], &w[nw - 8]); | 
|  | if (isplt != 0) { | 
|  | cftmdl1(128, &a[384], &w[nw - 64]); | 
|  | cftf161(&a[480], &w[nw - 8]); | 
|  | } else { | 
|  | cftmdl2(128, &a[384], &w[nw - 128]); | 
|  | cftf162(&a[480], &w[nw - 32]); | 
|  | } | 
|  | cftf161(&a[384], &w[nw - 8]); | 
|  | cftf162(&a[416], &w[nw - 32]); | 
|  | cftf161(&a[448], &w[nw - 8]); | 
|  | } else { | 
|  | cftmdl1(64, a, &w[nw - 32]); | 
|  | cftf081(a, &w[nw - 8]); | 
|  | cftf082(&a[16], &w[nw - 8]); | 
|  | cftf081(&a[32], &w[nw - 8]); | 
|  | cftf081(&a[48], &w[nw - 8]); | 
|  | cftmdl2(64, &a[64], &w[nw - 64]); | 
|  | cftf081(&a[64], &w[nw - 8]); | 
|  | cftf082(&a[80], &w[nw - 8]); | 
|  | cftf081(&a[96], &w[nw - 8]); | 
|  | cftf082(&a[112], &w[nw - 8]); | 
|  | cftmdl1(64, &a[128], &w[nw - 32]); | 
|  | cftf081(&a[128], &w[nw - 8]); | 
|  | cftf082(&a[144], &w[nw - 8]); | 
|  | cftf081(&a[160], &w[nw - 8]); | 
|  | cftf081(&a[176], &w[nw - 8]); | 
|  | if (isplt != 0) { | 
|  | cftmdl1(64, &a[192], &w[nw - 32]); | 
|  | cftf081(&a[240], &w[nw - 8]); | 
|  | } else { | 
|  | cftmdl2(64, &a[192], &w[nw - 64]); | 
|  | cftf082(&a[240], &w[nw - 8]); | 
|  | } | 
|  | cftf081(&a[192], &w[nw - 8]); | 
|  | cftf082(&a[208], &w[nw - 8]); | 
|  | cftf081(&a[224], &w[nw - 8]); | 
|  | } | 
|  | } | 
|  |  | 
|  |  | 
|  | void cftmdl1(int n, double *a, double *w) | 
|  | { | 
|  | int j, j0, j1, j2, j3, k, m, mh; | 
|  | double wn4r, wk1r, wk1i, wk3r, wk3i; | 
|  | double x0r, x0i, x1r, x1i, x2r, x2i, x3r, x3i; | 
|  |  | 
|  | mh = n >> 3; | 
|  | m = 2 * mh; | 
|  | j1 = m; | 
|  | j2 = j1 + m; | 
|  | j3 = j2 + m; | 
|  | x0r = a[0] + a[j2]; | 
|  | x0i = a[1] + a[j2 + 1]; | 
|  | x1r = a[0] - a[j2]; | 
|  | x1i = a[1] - a[j2 + 1]; | 
|  | x2r = a[j1] + a[j3]; | 
|  | x2i = a[j1 + 1] + a[j3 + 1]; | 
|  | x3r = a[j1] - a[j3]; | 
|  | x3i = a[j1 + 1] - a[j3 + 1]; | 
|  | a[0] = x0r + x2r; | 
|  | a[1] = x0i + x2i; | 
|  | a[j1] = x0r - x2r; | 
|  | a[j1 + 1] = x0i - x2i; | 
|  | a[j2] = x1r - x3i; | 
|  | a[j2 + 1] = x1i + x3r; | 
|  | a[j3] = x1r + x3i; | 
|  | a[j3 + 1] = x1i - x3r; | 
|  | wn4r = w[1]; | 
|  | k = 0; | 
|  | for (j = 2; j < mh; j += 2) { | 
|  | k += 4; | 
|  | wk1r = w[k]; | 
|  | wk1i = w[k + 1]; | 
|  | wk3r = w[k + 2]; | 
|  | wk3i = w[k + 3]; | 
|  | j1 = j + m; | 
|  | j2 = j1 + m; | 
|  | j3 = j2 + m; | 
|  | x0r = a[j] + a[j2]; | 
|  | x0i = a[j + 1] + a[j2 + 1]; | 
|  | x1r = a[j] - a[j2]; | 
|  | x1i = a[j + 1] - a[j2 + 1]; | 
|  | x2r = a[j1] + a[j3]; | 
|  | x2i = a[j1 + 1] + a[j3 + 1]; | 
|  | x3r = a[j1] - a[j3]; | 
|  | x3i = a[j1 + 1] - a[j3 + 1]; | 
|  | a[j] = x0r + x2r; | 
|  | a[j + 1] = x0i + x2i; | 
|  | a[j1] = x0r - x2r; | 
|  | a[j1 + 1] = x0i - x2i; | 
|  | x0r = x1r - x3i; | 
|  | x0i = x1i + x3r; | 
|  | a[j2] = wk1r * x0r - wk1i * x0i; | 
|  | a[j2 + 1] = wk1r * x0i + wk1i * x0r; | 
|  | x0r = x1r + x3i; | 
|  | x0i = x1i - x3r; | 
|  | a[j3] = wk3r * x0r + wk3i * x0i; | 
|  | a[j3 + 1] = wk3r * x0i - wk3i * x0r; | 
|  | j0 = m - j; | 
|  | j1 = j0 + m; | 
|  | j2 = j1 + m; | 
|  | j3 = j2 + m; | 
|  | x0r = a[j0] + a[j2]; | 
|  | x0i = a[j0 + 1] + a[j2 + 1]; | 
|  | x1r = a[j0] - a[j2]; | 
|  | x1i = a[j0 + 1] - a[j2 + 1]; | 
|  | x2r = a[j1] + a[j3]; | 
|  | x2i = a[j1 + 1] + a[j3 + 1]; | 
|  | x3r = a[j1] - a[j3]; | 
|  | x3i = a[j1 + 1] - a[j3 + 1]; | 
|  | a[j0] = x0r + x2r; | 
|  | a[j0 + 1] = x0i + x2i; | 
|  | a[j1] = x0r - x2r; | 
|  | a[j1 + 1] = x0i - x2i; | 
|  | x0r = x1r - x3i; | 
|  | x0i = x1i + x3r; | 
|  | a[j2] = wk1i * x0r - wk1r * x0i; | 
|  | a[j2 + 1] = wk1i * x0i + wk1r * x0r; | 
|  | x0r = x1r + x3i; | 
|  | x0i = x1i - x3r; | 
|  | a[j3] = wk3i * x0r + wk3r * x0i; | 
|  | a[j3 + 1] = wk3i * x0i - wk3r * x0r; | 
|  | } | 
|  | j0 = mh; | 
|  | j1 = j0 + m; | 
|  | j2 = j1 + m; | 
|  | j3 = j2 + m; | 
|  | x0r = a[j0] + a[j2]; | 
|  | x0i = a[j0 + 1] + a[j2 + 1]; | 
|  | x1r = a[j0] - a[j2]; | 
|  | x1i = a[j0 + 1] - a[j2 + 1]; | 
|  | x2r = a[j1] + a[j3]; | 
|  | x2i = a[j1 + 1] + a[j3 + 1]; | 
|  | x3r = a[j1] - a[j3]; | 
|  | x3i = a[j1 + 1] - a[j3 + 1]; | 
|  | a[j0] = x0r + x2r; | 
|  | a[j0 + 1] = x0i + x2i; | 
|  | a[j1] = x0r - x2r; | 
|  | a[j1 + 1] = x0i - x2i; | 
|  | x0r = x1r - x3i; | 
|  | x0i = x1i + x3r; | 
|  | a[j2] = wn4r * (x0r - x0i); | 
|  | a[j2 + 1] = wn4r * (x0i + x0r); | 
|  | x0r = x1r + x3i; | 
|  | x0i = x1i - x3r; | 
|  | a[j3] = -wn4r * (x0r + x0i); | 
|  | a[j3 + 1] = -wn4r * (x0i - x0r); | 
|  | } | 
|  |  | 
|  |  | 
|  | void cftmdl2(int n, double *a, double *w) | 
|  | { | 
|  | int j, j0, j1, j2, j3, k, kr, m, mh; | 
|  | double wn4r, wk1r, wk1i, wk3r, wk3i, wd1r, wd1i, wd3r, wd3i; | 
|  | double x0r, x0i, x1r, x1i, x2r, x2i, x3r, x3i, y0r, y0i, y2r, y2i; | 
|  |  | 
|  | mh = n >> 3; | 
|  | m = 2 * mh; | 
|  | wn4r = w[1]; | 
|  | j1 = m; | 
|  | j2 = j1 + m; | 
|  | j3 = j2 + m; | 
|  | x0r = a[0] - a[j2 + 1]; | 
|  | x0i = a[1] + a[j2]; | 
|  | x1r = a[0] + a[j2 + 1]; | 
|  | x1i = a[1] - a[j2]; | 
|  | x2r = a[j1] - a[j3 + 1]; | 
|  | x2i = a[j1 + 1] + a[j3]; | 
|  | x3r = a[j1] + a[j3 + 1]; | 
|  | x3i = a[j1 + 1] - a[j3]; | 
|  | y0r = wn4r * (x2r - x2i); | 
|  | y0i = wn4r * (x2i + x2r); | 
|  | a[0] = x0r + y0r; | 
|  | a[1] = x0i + y0i; | 
|  | a[j1] = x0r - y0r; | 
|  | a[j1 + 1] = x0i - y0i; | 
|  | y0r = wn4r * (x3r - x3i); | 
|  | y0i = wn4r * (x3i + x3r); | 
|  | a[j2] = x1r - y0i; | 
|  | a[j2 + 1] = x1i + y0r; | 
|  | a[j3] = x1r + y0i; | 
|  | a[j3 + 1] = x1i - y0r; | 
|  | k = 0; | 
|  | kr = 2 * m; | 
|  | for (j = 2; j < mh; j += 2) { | 
|  | k += 4; | 
|  | wk1r = w[k]; | 
|  | wk1i = w[k + 1]; | 
|  | wk3r = w[k + 2]; | 
|  | wk3i = w[k + 3]; | 
|  | kr -= 4; | 
|  | wd1i = w[kr]; | 
|  | wd1r = w[kr + 1]; | 
|  | wd3i = w[kr + 2]; | 
|  | wd3r = w[kr + 3]; | 
|  | j1 = j + m; | 
|  | j2 = j1 + m; | 
|  | j3 = j2 + m; | 
|  | x0r = a[j] - a[j2 + 1]; | 
|  | x0i = a[j + 1] + a[j2]; | 
|  | x1r = a[j] + a[j2 + 1]; | 
|  | x1i = a[j + 1] - a[j2]; | 
|  | x2r = a[j1] - a[j3 + 1]; | 
|  | x2i = a[j1 + 1] + a[j3]; | 
|  | x3r = a[j1] + a[j3 + 1]; | 
|  | x3i = a[j1 + 1] - a[j3]; | 
|  | y0r = wk1r * x0r - wk1i * x0i; | 
|  | y0i = wk1r * x0i + wk1i * x0r; | 
|  | y2r = wd1r * x2r - wd1i * x2i; | 
|  | y2i = wd1r * x2i + wd1i * x2r; | 
|  | a[j] = y0r + y2r; | 
|  | a[j + 1] = y0i + y2i; | 
|  | a[j1] = y0r - y2r; | 
|  | a[j1 + 1] = y0i - y2i; | 
|  | y0r = wk3r * x1r + wk3i * x1i; | 
|  | y0i = wk3r * x1i - wk3i * x1r; | 
|  | y2r = wd3r * x3r + wd3i * x3i; | 
|  | y2i = wd3r * x3i - wd3i * x3r; | 
|  | a[j2] = y0r + y2r; | 
|  | a[j2 + 1] = y0i + y2i; | 
|  | a[j3] = y0r - y2r; | 
|  | a[j3 + 1] = y0i - y2i; | 
|  | j0 = m - j; | 
|  | j1 = j0 + m; | 
|  | j2 = j1 + m; | 
|  | j3 = j2 + m; | 
|  | x0r = a[j0] - a[j2 + 1]; | 
|  | x0i = a[j0 + 1] + a[j2]; | 
|  | x1r = a[j0] + a[j2 + 1]; | 
|  | x1i = a[j0 + 1] - a[j2]; | 
|  | x2r = a[j1] - a[j3 + 1]; | 
|  | x2i = a[j1 + 1] + a[j3]; | 
|  | x3r = a[j1] + a[j3 + 1]; | 
|  | x3i = a[j1 + 1] - a[j3]; | 
|  | y0r = wd1i * x0r - wd1r * x0i; | 
|  | y0i = wd1i * x0i + wd1r * x0r; | 
|  | y2r = wk1i * x2r - wk1r * x2i; | 
|  | y2i = wk1i * x2i + wk1r * x2r; | 
|  | a[j0] = y0r + y2r; | 
|  | a[j0 + 1] = y0i + y2i; | 
|  | a[j1] = y0r - y2r; | 
|  | a[j1 + 1] = y0i - y2i; | 
|  | y0r = wd3i * x1r + wd3r * x1i; | 
|  | y0i = wd3i * x1i - wd3r * x1r; | 
|  | y2r = wk3i * x3r + wk3r * x3i; | 
|  | y2i = wk3i * x3i - wk3r * x3r; | 
|  | a[j2] = y0r + y2r; | 
|  | a[j2 + 1] = y0i + y2i; | 
|  | a[j3] = y0r - y2r; | 
|  | a[j3 + 1] = y0i - y2i; | 
|  | } | 
|  | wk1r = w[m]; | 
|  | wk1i = w[m + 1]; | 
|  | j0 = mh; | 
|  | j1 = j0 + m; | 
|  | j2 = j1 + m; | 
|  | j3 = j2 + m; | 
|  | x0r = a[j0] - a[j2 + 1]; | 
|  | x0i = a[j0 + 1] + a[j2]; | 
|  | x1r = a[j0] + a[j2 + 1]; | 
|  | x1i = a[j0 + 1] - a[j2]; | 
|  | x2r = a[j1] - a[j3 + 1]; | 
|  | x2i = a[j1 + 1] + a[j3]; | 
|  | x3r = a[j1] + a[j3 + 1]; | 
|  | x3i = a[j1 + 1] - a[j3]; | 
|  | y0r = wk1r * x0r - wk1i * x0i; | 
|  | y0i = wk1r * x0i + wk1i * x0r; | 
|  | y2r = wk1i * x2r - wk1r * x2i; | 
|  | y2i = wk1i * x2i + wk1r * x2r; | 
|  | a[j0] = y0r + y2r; | 
|  | a[j0 + 1] = y0i + y2i; | 
|  | a[j1] = y0r - y2r; | 
|  | a[j1 + 1] = y0i - y2i; | 
|  | y0r = wk1i * x1r - wk1r * x1i; | 
|  | y0i = wk1i * x1i + wk1r * x1r; | 
|  | y2r = wk1r * x3r - wk1i * x3i; | 
|  | y2i = wk1r * x3i + wk1i * x3r; | 
|  | a[j2] = y0r - y2r; | 
|  | a[j2 + 1] = y0i - y2i; | 
|  | a[j3] = y0r + y2r; | 
|  | a[j3 + 1] = y0i + y2i; | 
|  | } | 
|  |  | 
|  |  | 
|  | void cftfx41(int n, double *a, int nw, double *w) | 
|  | { | 
|  | void cftf161(double *a, double *w); | 
|  | void cftf162(double *a, double *w); | 
|  | void cftf081(double *a, double *w); | 
|  | void cftf082(double *a, double *w); | 
|  |  | 
|  | if (n == 128) { | 
|  | cftf161(a, &w[nw - 8]); | 
|  | cftf162(&a[32], &w[nw - 32]); | 
|  | cftf161(&a[64], &w[nw - 8]); | 
|  | cftf161(&a[96], &w[nw - 8]); | 
|  | } else { | 
|  | cftf081(a, &w[nw - 8]); | 
|  | cftf082(&a[16], &w[nw - 8]); | 
|  | cftf081(&a[32], &w[nw - 8]); | 
|  | cftf081(&a[48], &w[nw - 8]); | 
|  | } | 
|  | } | 
|  |  | 
|  |  | 
|  | void cftf161(double *a, double *w) | 
|  | { | 
|  | double wn4r, wk1r, wk1i, | 
|  | x0r, x0i, x1r, x1i, x2r, x2i, x3r, x3i, | 
|  | y0r, y0i, y1r, y1i, y2r, y2i, y3r, y3i, | 
|  | y4r, y4i, y5r, y5i, y6r, y6i, y7r, y7i, | 
|  | y8r, y8i, y9r, y9i, y10r, y10i, y11r, y11i, | 
|  | y12r, y12i, y13r, y13i, y14r, y14i, y15r, y15i; | 
|  |  | 
|  | wn4r = w[1]; | 
|  | wk1r = w[2]; | 
|  | wk1i = w[3]; | 
|  | x0r = a[0] + a[16]; | 
|  | x0i = a[1] + a[17]; | 
|  | x1r = a[0] - a[16]; | 
|  | x1i = a[1] - a[17]; | 
|  | x2r = a[8] + a[24]; | 
|  | x2i = a[9] + a[25]; | 
|  | x3r = a[8] - a[24]; | 
|  | x3i = a[9] - a[25]; | 
|  | y0r = x0r + x2r; | 
|  | y0i = x0i + x2i; | 
|  | y4r = x0r - x2r; | 
|  | y4i = x0i - x2i; | 
|  | y8r = x1r - x3i; | 
|  | y8i = x1i + x3r; | 
|  | y12r = x1r + x3i; | 
|  | y12i = x1i - x3r; | 
|  | x0r = a[2] + a[18]; | 
|  | x0i = a[3] + a[19]; | 
|  | x1r = a[2] - a[18]; | 
|  | x1i = a[3] - a[19]; | 
|  | x2r = a[10] + a[26]; | 
|  | x2i = a[11] + a[27]; | 
|  | x3r = a[10] - a[26]; | 
|  | x3i = a[11] - a[27]; | 
|  | y1r = x0r + x2r; | 
|  | y1i = x0i + x2i; | 
|  | y5r = x0r - x2r; | 
|  | y5i = x0i - x2i; | 
|  | x0r = x1r - x3i; | 
|  | x0i = x1i + x3r; | 
|  | y9r = wk1r * x0r - wk1i * x0i; | 
|  | y9i = wk1r * x0i + wk1i * x0r; | 
|  | x0r = x1r + x3i; | 
|  | x0i = x1i - x3r; | 
|  | y13r = wk1i * x0r - wk1r * x0i; | 
|  | y13i = wk1i * x0i + wk1r * x0r; | 
|  | x0r = a[4] + a[20]; | 
|  | x0i = a[5] + a[21]; | 
|  | x1r = a[4] - a[20]; | 
|  | x1i = a[5] - a[21]; | 
|  | x2r = a[12] + a[28]; | 
|  | x2i = a[13] + a[29]; | 
|  | x3r = a[12] - a[28]; | 
|  | x3i = a[13] - a[29]; | 
|  | y2r = x0r + x2r; | 
|  | y2i = x0i + x2i; | 
|  | y6r = x0r - x2r; | 
|  | y6i = x0i - x2i; | 
|  | x0r = x1r - x3i; | 
|  | x0i = x1i + x3r; | 
|  | y10r = wn4r * (x0r - x0i); | 
|  | y10i = wn4r * (x0i + x0r); | 
|  | x0r = x1r + x3i; | 
|  | x0i = x1i - x3r; | 
|  | y14r = wn4r * (x0r + x0i); | 
|  | y14i = wn4r * (x0i - x0r); | 
|  | x0r = a[6] + a[22]; | 
|  | x0i = a[7] + a[23]; | 
|  | x1r = a[6] - a[22]; | 
|  | x1i = a[7] - a[23]; | 
|  | x2r = a[14] + a[30]; | 
|  | x2i = a[15] + a[31]; | 
|  | x3r = a[14] - a[30]; | 
|  | x3i = a[15] - a[31]; | 
|  | y3r = x0r + x2r; | 
|  | y3i = x0i + x2i; | 
|  | y7r = x0r - x2r; | 
|  | y7i = x0i - x2i; | 
|  | x0r = x1r - x3i; | 
|  | x0i = x1i + x3r; | 
|  | y11r = wk1i * x0r - wk1r * x0i; | 
|  | y11i = wk1i * x0i + wk1r * x0r; | 
|  | x0r = x1r + x3i; | 
|  | x0i = x1i - x3r; | 
|  | y15r = wk1r * x0r - wk1i * x0i; | 
|  | y15i = wk1r * x0i + wk1i * x0r; | 
|  | x0r = y12r - y14r; | 
|  | x0i = y12i - y14i; | 
|  | x1r = y12r + y14r; | 
|  | x1i = y12i + y14i; | 
|  | x2r = y13r - y15r; | 
|  | x2i = y13i - y15i; | 
|  | x3r = y13r + y15r; | 
|  | x3i = y13i + y15i; | 
|  | a[24] = x0r + x2r; | 
|  | a[25] = x0i + x2i; | 
|  | a[26] = x0r - x2r; | 
|  | a[27] = x0i - x2i; | 
|  | a[28] = x1r - x3i; | 
|  | a[29] = x1i + x3r; | 
|  | a[30] = x1r + x3i; | 
|  | a[31] = x1i - x3r; | 
|  | x0r = y8r + y10r; | 
|  | x0i = y8i + y10i; | 
|  | x1r = y8r - y10r; | 
|  | x1i = y8i - y10i; | 
|  | x2r = y9r + y11r; | 
|  | x2i = y9i + y11i; | 
|  | x3r = y9r - y11r; | 
|  | x3i = y9i - y11i; | 
|  | a[16] = x0r + x2r; | 
|  | a[17] = x0i + x2i; | 
|  | a[18] = x0r - x2r; | 
|  | a[19] = x0i - x2i; | 
|  | a[20] = x1r - x3i; | 
|  | a[21] = x1i + x3r; | 
|  | a[22] = x1r + x3i; | 
|  | a[23] = x1i - x3r; | 
|  | x0r = y5r - y7i; | 
|  | x0i = y5i + y7r; | 
|  | x2r = wn4r * (x0r - x0i); | 
|  | x2i = wn4r * (x0i + x0r); | 
|  | x0r = y5r + y7i; | 
|  | x0i = y5i - y7r; | 
|  | x3r = wn4r * (x0r - x0i); | 
|  | x3i = wn4r * (x0i + x0r); | 
|  | x0r = y4r - y6i; | 
|  | x0i = y4i + y6r; | 
|  | x1r = y4r + y6i; | 
|  | x1i = y4i - y6r; | 
|  | a[8] = x0r + x2r; | 
|  | a[9] = x0i + x2i; | 
|  | a[10] = x0r - x2r; | 
|  | a[11] = x0i - x2i; | 
|  | a[12] = x1r - x3i; | 
|  | a[13] = x1i + x3r; | 
|  | a[14] = x1r + x3i; | 
|  | a[15] = x1i - x3r; | 
|  | x0r = y0r + y2r; | 
|  | x0i = y0i + y2i; | 
|  | x1r = y0r - y2r; | 
|  | x1i = y0i - y2i; | 
|  | x2r = y1r + y3r; | 
|  | x2i = y1i + y3i; | 
|  | x3r = y1r - y3r; | 
|  | x3i = y1i - y3i; | 
|  | a[0] = x0r + x2r; | 
|  | a[1] = x0i + x2i; | 
|  | a[2] = x0r - x2r; | 
|  | a[3] = x0i - x2i; | 
|  | a[4] = x1r - x3i; | 
|  | a[5] = x1i + x3r; | 
|  | a[6] = x1r + x3i; | 
|  | a[7] = x1i - x3r; | 
|  | } | 
|  |  | 
|  |  | 
|  | void cftf162(double *a, double *w) | 
|  | { | 
|  | double wn4r, wk1r, wk1i, wk2r, wk2i, wk3r, wk3i, | 
|  | x0r, x0i, x1r, x1i, x2r, x2i, | 
|  | y0r, y0i, y1r, y1i, y2r, y2i, y3r, y3i, | 
|  | y4r, y4i, y5r, y5i, y6r, y6i, y7r, y7i, | 
|  | y8r, y8i, y9r, y9i, y10r, y10i, y11r, y11i, | 
|  | y12r, y12i, y13r, y13i, y14r, y14i, y15r, y15i; | 
|  |  | 
|  | wn4r = w[1]; | 
|  | wk1r = w[4]; | 
|  | wk1i = w[5]; | 
|  | wk3r = w[6]; | 
|  | wk3i = -w[7]; | 
|  | wk2r = w[8]; | 
|  | wk2i = w[9]; | 
|  | x1r = a[0] - a[17]; | 
|  | x1i = a[1] + a[16]; | 
|  | x0r = a[8] - a[25]; | 
|  | x0i = a[9] + a[24]; | 
|  | x2r = wn4r * (x0r - x0i); | 
|  | x2i = wn4r * (x0i + x0r); | 
|  | y0r = x1r + x2r; | 
|  | y0i = x1i + x2i; | 
|  | y4r = x1r - x2r; | 
|  | y4i = x1i - x2i; | 
|  | x1r = a[0] + a[17]; | 
|  | x1i = a[1] - a[16]; | 
|  | x0r = a[8] + a[25]; | 
|  | x0i = a[9] - a[24]; | 
|  | x2r = wn4r * (x0r - x0i); | 
|  | x2i = wn4r * (x0i + x0r); | 
|  | y8r = x1r - x2i; | 
|  | y8i = x1i + x2r; | 
|  | y12r = x1r + x2i; | 
|  | y12i = x1i - x2r; | 
|  | x0r = a[2] - a[19]; | 
|  | x0i = a[3] + a[18]; | 
|  | x1r = wk1r * x0r - wk1i * x0i; | 
|  | x1i = wk1r * x0i + wk1i * x0r; | 
|  | x0r = a[10] - a[27]; | 
|  | x0i = a[11] + a[26]; | 
|  | x2r = wk3i * x0r - wk3r * x0i; | 
|  | x2i = wk3i * x0i + wk3r * x0r; | 
|  | y1r = x1r + x2r; | 
|  | y1i = x1i + x2i; | 
|  | y5r = x1r - x2r; | 
|  | y5i = x1i - x2i; | 
|  | x0r = a[2] + a[19]; | 
|  | x0i = a[3] - a[18]; | 
|  | x1r = wk3r * x0r - wk3i * x0i; | 
|  | x1i = wk3r * x0i + wk3i * x0r; | 
|  | x0r = a[10] + a[27]; | 
|  | x0i = a[11] - a[26]; | 
|  | x2r = wk1r * x0r + wk1i * x0i; | 
|  | x2i = wk1r * x0i - wk1i * x0r; | 
|  | y9r = x1r - x2r; | 
|  | y9i = x1i - x2i; | 
|  | y13r = x1r + x2r; | 
|  | y13i = x1i + x2i; | 
|  | x0r = a[4] - a[21]; | 
|  | x0i = a[5] + a[20]; | 
|  | x1r = wk2r * x0r - wk2i * x0i; | 
|  | x1i = wk2r * x0i + wk2i * x0r; | 
|  | x0r = a[12] - a[29]; | 
|  | x0i = a[13] + a[28]; | 
|  | x2r = wk2i * x0r - wk2r * x0i; | 
|  | x2i = wk2i * x0i + wk2r * x0r; | 
|  | y2r = x1r + x2r; | 
|  | y2i = x1i + x2i; | 
|  | y6r = x1r - x2r; | 
|  | y6i = x1i - x2i; | 
|  | x0r = a[4] + a[21]; | 
|  | x0i = a[5] - a[20]; | 
|  | x1r = wk2i * x0r - wk2r * x0i; | 
|  | x1i = wk2i * x0i + wk2r * x0r; | 
|  | x0r = a[12] + a[29]; | 
|  | x0i = a[13] - a[28]; | 
|  | x2r = wk2r * x0r - wk2i * x0i; | 
|  | x2i = wk2r * x0i + wk2i * x0r; | 
|  | y10r = x1r - x2r; | 
|  | y10i = x1i - x2i; | 
|  | y14r = x1r + x2r; | 
|  | y14i = x1i + x2i; | 
|  | x0r = a[6] - a[23]; | 
|  | x0i = a[7] + a[22]; | 
|  | x1r = wk3r * x0r - wk3i * x0i; | 
|  | x1i = wk3r * x0i + wk3i * x0r; | 
|  | x0r = a[14] - a[31]; | 
|  | x0i = a[15] + a[30]; | 
|  | x2r = wk1i * x0r - wk1r * x0i; | 
|  | x2i = wk1i * x0i + wk1r * x0r; | 
|  | y3r = x1r + x2r; | 
|  | y3i = x1i + x2i; | 
|  | y7r = x1r - x2r; | 
|  | y7i = x1i - x2i; | 
|  | x0r = a[6] + a[23]; | 
|  | x0i = a[7] - a[22]; | 
|  | x1r = wk1i * x0r + wk1r * x0i; | 
|  | x1i = wk1i * x0i - wk1r * x0r; | 
|  | x0r = a[14] + a[31]; | 
|  | x0i = a[15] - a[30]; | 
|  | x2r = wk3i * x0r - wk3r * x0i; | 
|  | x2i = wk3i * x0i + wk3r * x0r; | 
|  | y11r = x1r + x2r; | 
|  | y11i = x1i + x2i; | 
|  | y15r = x1r - x2r; | 
|  | y15i = x1i - x2i; | 
|  | x1r = y0r + y2r; | 
|  | x1i = y0i + y2i; | 
|  | x2r = y1r + y3r; | 
|  | x2i = y1i + y3i; | 
|  | a[0] = x1r + x2r; | 
|  | a[1] = x1i + x2i; | 
|  | a[2] = x1r - x2r; | 
|  | a[3] = x1i - x2i; | 
|  | x1r = y0r - y2r; | 
|  | x1i = y0i - y2i; | 
|  | x2r = y1r - y3r; | 
|  | x2i = y1i - y3i; | 
|  | a[4] = x1r - x2i; | 
|  | a[5] = x1i + x2r; | 
|  | a[6] = x1r + x2i; | 
|  | a[7] = x1i - x2r; | 
|  | x1r = y4r - y6i; | 
|  | x1i = y4i + y6r; | 
|  | x0r = y5r - y7i; | 
|  | x0i = y5i + y7r; | 
|  | x2r = wn4r * (x0r - x0i); | 
|  | x2i = wn4r * (x0i + x0r); | 
|  | a[8] = x1r + x2r; | 
|  | a[9] = x1i + x2i; | 
|  | a[10] = x1r - x2r; | 
|  | a[11] = x1i - x2i; | 
|  | x1r = y4r + y6i; | 
|  | x1i = y4i - y6r; | 
|  | x0r = y5r + y7i; | 
|  | x0i = y5i - y7r; | 
|  | x2r = wn4r * (x0r - x0i); | 
|  | x2i = wn4r * (x0i + x0r); | 
|  | a[12] = x1r - x2i; | 
|  | a[13] = x1i + x2r; | 
|  | a[14] = x1r + x2i; | 
|  | a[15] = x1i - x2r; | 
|  | x1r = y8r + y10r; | 
|  | x1i = y8i + y10i; | 
|  | x2r = y9r - y11r; | 
|  | x2i = y9i - y11i; | 
|  | a[16] = x1r + x2r; | 
|  | a[17] = x1i + x2i; | 
|  | a[18] = x1r - x2r; | 
|  | a[19] = x1i - x2i; | 
|  | x1r = y8r - y10r; | 
|  | x1i = y8i - y10i; | 
|  | x2r = y9r + y11r; | 
|  | x2i = y9i + y11i; | 
|  | a[20] = x1r - x2i; | 
|  | a[21] = x1i + x2r; | 
|  | a[22] = x1r + x2i; | 
|  | a[23] = x1i - x2r; | 
|  | x1r = y12r - y14i; | 
|  | x1i = y12i + y14r; | 
|  | x0r = y13r + y15i; | 
|  | x0i = y13i - y15r; | 
|  | x2r = wn4r * (x0r - x0i); | 
|  | x2i = wn4r * (x0i + x0r); | 
|  | a[24] = x1r + x2r; | 
|  | a[25] = x1i + x2i; | 
|  | a[26] = x1r - x2r; | 
|  | a[27] = x1i - x2i; | 
|  | x1r = y12r + y14i; | 
|  | x1i = y12i - y14r; | 
|  | x0r = y13r - y15i; | 
|  | x0i = y13i + y15r; | 
|  | x2r = wn4r * (x0r - x0i); | 
|  | x2i = wn4r * (x0i + x0r); | 
|  | a[28] = x1r - x2i; | 
|  | a[29] = x1i + x2r; | 
|  | a[30] = x1r + x2i; | 
|  | a[31] = x1i - x2r; | 
|  | } | 
|  |  | 
|  |  | 
|  | void cftf081(double *a, double *w) | 
|  | { | 
|  | double wn4r, x0r, x0i, x1r, x1i, x2r, x2i, x3r, x3i, | 
|  | y0r, y0i, y1r, y1i, y2r, y2i, y3r, y3i, | 
|  | y4r, y4i, y5r, y5i, y6r, y6i, y7r, y7i; | 
|  |  | 
|  | wn4r = w[1]; | 
|  | x0r = a[0] + a[8]; | 
|  | x0i = a[1] + a[9]; | 
|  | x1r = a[0] - a[8]; | 
|  | x1i = a[1] - a[9]; | 
|  | x2r = a[4] + a[12]; | 
|  | x2i = a[5] + a[13]; | 
|  | x3r = a[4] - a[12]; | 
|  | x3i = a[5] - a[13]; | 
|  | y0r = x0r + x2r; | 
|  | y0i = x0i + x2i; | 
|  | y2r = x0r - x2r; | 
|  | y2i = x0i - x2i; | 
|  | y1r = x1r - x3i; | 
|  | y1i = x1i + x3r; | 
|  | y3r = x1r + x3i; | 
|  | y3i = x1i - x3r; | 
|  | x0r = a[2] + a[10]; | 
|  | x0i = a[3] + a[11]; | 
|  | x1r = a[2] - a[10]; | 
|  | x1i = a[3] - a[11]; | 
|  | x2r = a[6] + a[14]; | 
|  | x2i = a[7] + a[15]; | 
|  | x3r = a[6] - a[14]; | 
|  | x3i = a[7] - a[15]; | 
|  | y4r = x0r + x2r; | 
|  | y4i = x0i + x2i; | 
|  | y6r = x0r - x2r; | 
|  | y6i = x0i - x2i; | 
|  | x0r = x1r - x3i; | 
|  | x0i = x1i + x3r; | 
|  | x2r = x1r + x3i; | 
|  | x2i = x1i - x3r; | 
|  | y5r = wn4r * (x0r - x0i); | 
|  | y5i = wn4r * (x0r + x0i); | 
|  | y7r = wn4r * (x2r - x2i); | 
|  | y7i = wn4r * (x2r + x2i); | 
|  | a[8] = y1r + y5r; | 
|  | a[9] = y1i + y5i; | 
|  | a[10] = y1r - y5r; | 
|  | a[11] = y1i - y5i; | 
|  | a[12] = y3r - y7i; | 
|  | a[13] = y3i + y7r; | 
|  | a[14] = y3r + y7i; | 
|  | a[15] = y3i - y7r; | 
|  | a[0] = y0r + y4r; | 
|  | a[1] = y0i + y4i; | 
|  | a[2] = y0r - y4r; | 
|  | a[3] = y0i - y4i; | 
|  | a[4] = y2r - y6i; | 
|  | a[5] = y2i + y6r; | 
|  | a[6] = y2r + y6i; | 
|  | a[7] = y2i - y6r; | 
|  | } | 
|  |  | 
|  |  | 
|  | void cftf082(double *a, double *w) | 
|  | { | 
|  | double wn4r, wk1r, wk1i, x0r, x0i, x1r, x1i, | 
|  | y0r, y0i, y1r, y1i, y2r, y2i, y3r, y3i, | 
|  | y4r, y4i, y5r, y5i, y6r, y6i, y7r, y7i; | 
|  |  | 
|  | wn4r = w[1]; | 
|  | wk1r = w[2]; | 
|  | wk1i = w[3]; | 
|  | y0r = a[0] - a[9]; | 
|  | y0i = a[1] + a[8]; | 
|  | y1r = a[0] + a[9]; | 
|  | y1i = a[1] - a[8]; | 
|  | x0r = a[4] - a[13]; | 
|  | x0i = a[5] + a[12]; | 
|  | y2r = wn4r * (x0r - x0i); | 
|  | y2i = wn4r * (x0i + x0r); | 
|  | x0r = a[4] + a[13]; | 
|  | x0i = a[5] - a[12]; | 
|  | y3r = wn4r * (x0r - x0i); | 
|  | y3i = wn4r * (x0i + x0r); | 
|  | x0r = a[2] - a[11]; | 
|  | x0i = a[3] + a[10]; | 
|  | y4r = wk1r * x0r - wk1i * x0i; | 
|  | y4i = wk1r * x0i + wk1i * x0r; | 
|  | x0r = a[2] + a[11]; | 
|  | x0i = a[3] - a[10]; | 
|  | y5r = wk1i * x0r - wk1r * x0i; | 
|  | y5i = wk1i * x0i + wk1r * x0r; | 
|  | x0r = a[6] - a[15]; | 
|  | x0i = a[7] + a[14]; | 
|  | y6r = wk1i * x0r - wk1r * x0i; | 
|  | y6i = wk1i * x0i + wk1r * x0r; | 
|  | x0r = a[6] + a[15]; | 
|  | x0i = a[7] - a[14]; | 
|  | y7r = wk1r * x0r - wk1i * x0i; | 
|  | y7i = wk1r * x0i + wk1i * x0r; | 
|  | x0r = y0r + y2r; | 
|  | x0i = y0i + y2i; | 
|  | x1r = y4r + y6r; | 
|  | x1i = y4i + y6i; | 
|  | a[0] = x0r + x1r; | 
|  | a[1] = x0i + x1i; | 
|  | a[2] = x0r - x1r; | 
|  | a[3] = x0i - x1i; | 
|  | x0r = y0r - y2r; | 
|  | x0i = y0i - y2i; | 
|  | x1r = y4r - y6r; | 
|  | x1i = y4i - y6i; | 
|  | a[4] = x0r - x1i; | 
|  | a[5] = x0i + x1r; | 
|  | a[6] = x0r + x1i; | 
|  | a[7] = x0i - x1r; | 
|  | x0r = y1r - y3i; | 
|  | x0i = y1i + y3r; | 
|  | x1r = y5r - y7r; | 
|  | x1i = y5i - y7i; | 
|  | a[8] = x0r + x1r; | 
|  | a[9] = x0i + x1i; | 
|  | a[10] = x0r - x1r; | 
|  | a[11] = x0i - x1i; | 
|  | x0r = y1r + y3i; | 
|  | x0i = y1i - y3r; | 
|  | x1r = y5r + y7r; | 
|  | x1i = y5i + y7i; | 
|  | a[12] = x0r - x1i; | 
|  | a[13] = x0i + x1r; | 
|  | a[14] = x0r + x1i; | 
|  | a[15] = x0i - x1r; | 
|  | } | 
|  |  | 
|  |  | 
|  | void cftf040(double *a) | 
|  | { | 
|  | double x0r, x0i, x1r, x1i, x2r, x2i, x3r, x3i; | 
|  |  | 
|  | x0r = a[0] + a[4]; | 
|  | x0i = a[1] + a[5]; | 
|  | x1r = a[0] - a[4]; | 
|  | x1i = a[1] - a[5]; | 
|  | x2r = a[2] + a[6]; | 
|  | x2i = a[3] + a[7]; | 
|  | x3r = a[2] - a[6]; | 
|  | x3i = a[3] - a[7]; | 
|  | a[0] = x0r + x2r; | 
|  | a[1] = x0i + x2i; | 
|  | a[2] = x1r - x3i; | 
|  | a[3] = x1i + x3r; | 
|  | a[4] = x0r - x2r; | 
|  | a[5] = x0i - x2i; | 
|  | a[6] = x1r + x3i; | 
|  | a[7] = x1i - x3r; | 
|  | } | 
|  |  | 
|  |  | 
|  | void cftb040(double *a) | 
|  | { | 
|  | double x0r, x0i, x1r, x1i, x2r, x2i, x3r, x3i; | 
|  |  | 
|  | x0r = a[0] + a[4]; | 
|  | x0i = a[1] + a[5]; | 
|  | x1r = a[0] - a[4]; | 
|  | x1i = a[1] - a[5]; | 
|  | x2r = a[2] + a[6]; | 
|  | x2i = a[3] + a[7]; | 
|  | x3r = a[2] - a[6]; | 
|  | x3i = a[3] - a[7]; | 
|  | a[0] = x0r + x2r; | 
|  | a[1] = x0i + x2i; | 
|  | a[2] = x1r + x3i; | 
|  | a[3] = x1i - x3r; | 
|  | a[4] = x0r - x2r; | 
|  | a[5] = x0i - x2i; | 
|  | a[6] = x1r - x3i; | 
|  | a[7] = x1i + x3r; | 
|  | } | 
|  |  | 
|  |  | 
|  | void cftx020(double *a) | 
|  | { | 
|  | double x0r, x0i; | 
|  |  | 
|  | x0r = a[0] - a[2]; | 
|  | x0i = a[1] - a[3]; | 
|  | a[0] += a[2]; | 
|  | a[1] += a[3]; | 
|  | a[2] = x0r; | 
|  | a[3] = x0i; | 
|  | } | 
|  |  | 
|  |  | 
|  | void rftfsub(int n, double *a, int nc, double *c) | 
|  | { | 
|  | int j, k, kk, ks, m; | 
|  | double wkr, wki, xr, xi, yr, yi; | 
|  |  | 
|  | m = n >> 1; | 
|  | ks = 2 * nc / m; | 
|  | kk = 0; | 
|  | for (j = 2; j < m; j += 2) { | 
|  | k = n - j; | 
|  | kk += ks; | 
|  | wkr = 0.5 - c[nc - kk]; | 
|  | wki = c[kk]; | 
|  | xr = a[j] - a[k]; | 
|  | xi = a[j + 1] + a[k + 1]; | 
|  | yr = wkr * xr - wki * xi; | 
|  | yi = wkr * xi + wki * xr; | 
|  | a[j] -= yr; | 
|  | a[j + 1] -= yi; | 
|  | a[k] += yr; | 
|  | a[k + 1] -= yi; | 
|  | } | 
|  | } | 
|  |  | 
|  |  | 
|  | void rftbsub(int n, double *a, int nc, double *c) | 
|  | { | 
|  | int j, k, kk, ks, m; | 
|  | double wkr, wki, xr, xi, yr, yi; | 
|  |  | 
|  | m = n >> 1; | 
|  | ks = 2 * nc / m; | 
|  | kk = 0; | 
|  | for (j = 2; j < m; j += 2) { | 
|  | k = n - j; | 
|  | kk += ks; | 
|  | wkr = 0.5 - c[nc - kk]; | 
|  | wki = c[kk]; | 
|  | xr = a[j] - a[k]; | 
|  | xi = a[j + 1] + a[k + 1]; | 
|  | yr = wkr * xr + wki * xi; | 
|  | yi = wkr * xi - wki * xr; | 
|  | a[j] -= yr; | 
|  | a[j + 1] -= yi; | 
|  | a[k] += yr; | 
|  | a[k + 1] -= yi; | 
|  | } | 
|  | } | 
|  |  | 
|  |  | 
|  | void dctsub(int n, double *a, int nc, double *c) | 
|  | { | 
|  | int j, k, kk, ks, m; | 
|  | double wkr, wki, xr; | 
|  |  | 
|  | m = n >> 1; | 
|  | ks = nc / n; | 
|  | kk = 0; | 
|  | for (j = 1; j < m; j++) { | 
|  | k = n - j; | 
|  | kk += ks; | 
|  | wkr = c[kk] - c[nc - kk]; | 
|  | wki = c[kk] + c[nc - kk]; | 
|  | xr = wki * a[j] - wkr * a[k]; | 
|  | a[j] = wkr * a[j] + wki * a[k]; | 
|  | a[k] = xr; | 
|  | } | 
|  | a[m] *= c[0]; | 
|  | } | 
|  |  | 
|  |  | 
|  | void dstsub(int n, double *a, int nc, double *c) | 
|  | { | 
|  | int j, k, kk, ks, m; | 
|  | double wkr, wki, xr; | 
|  |  | 
|  | m = n >> 1; | 
|  | ks = nc / n; | 
|  | kk = 0; | 
|  | for (j = 1; j < m; j++) { | 
|  | k = n - j; | 
|  | kk += ks; | 
|  | wkr = c[kk] - c[nc - kk]; | 
|  | wki = c[kk] + c[nc - kk]; | 
|  | xr = wki * a[k] - wkr * a[j]; | 
|  | a[k] = wkr * a[k] + wki * a[j]; | 
|  | a[j] = xr; | 
|  | } | 
|  | a[m] *= c[0]; | 
|  | } | 
|  |  |